The increased prevalence of postoperative arthrofibrosis after multi-ligament knee injuries (MLKI) compared to isolated anterior cruciate ligament (ACL) injuries has been proposed to be due, in part, to patient factors limiting physical therapy utilization. The purpose of this study was to compare demographic factors, pre- and postoperative physical therapy utilization, and the need for motion-restoring surgery between MLKI and ACL-injured patients. Using the PearlDiver Mariner 151 database, two cohorts matched by age and sex were identified using current procedural terminology (CPT) codes and included those age 16 or greater that underwent isolated ACL (n=3801) vs. MLKI reconstruction (n=3801). The number of pre- and postoperative physical therapy visits was recorded, as was the need for motion-restoring surgery (arthroscopic lysis of adhesions or manipulation under anesthesia). Demographic factors, physical therapy utilization, and the prevalence of motion-restoring surgery were compared between the MLKI and ACL groups using t-tests or chi-square tests, as appropriate. A significantly greater proportion of those with MLKI underwent subsequent motion-restoring surgery (MLKI=412/3081 (13.4%) vs. ACL=84/3081 (2.7%), p<0.001; odds ratio = 5.5 , p<0.0001). Following surgery, less than half of those with MLKI that underwent subsequent motion-restoring surgery attended physical therapy, which was significantly lower than those who did not require motion-restoring surgery (p<0.0001). The prevalence of motion-restoring surgery was significantly greater after MLKI when compared to an isolated ACL injury. While the etiology of arthrofibrosis after MLKI is likely complex, the current results suggest that demographic factors and physical therapy utilization are not solely responsible for the increased risk of arthrofibrosis after MLKI. Individual patient cohorts have reported that arthrofibrosis is more common following surgical treatment of multi-ligament knee injuries (MLKI) than isolated anterior cruciate ligament (ACL) injuries -3. The iUsing the current procedural terminology (CPT) codes, we identified two patient cohorts within the PearlDiver Mariner 151 database. This insurance claims database includes information on more than 151 million orthopedic patients. We identified those having isolated ACL reconstruction, and we operationally defined MLKI in this study as persons undergoing surgical treatment of an ACL tear in addition to another ligamentous procedure on the same day  vs. ACL = 84/3081 (2.7%), p<0.001). This corresponded with a significantly greater odds ratio of undergoing motion-restoring surgery following MLKI , p<0.0001). In the MLKI group, those that underwent motion-restoring surgery were significantly older and more often female, with fewer patients having commercial insurance . Systematic reviews and large single-center series have reported a greater prevalence of 11.2% and 4.5% for MLKI and isolated ACL injuries, respectively [The etiology of postoperative arthrofibrosis is likely complex, and the current results indicate patient factors and/or physical therapy utilization do not explain the increased risk of arthrofibrosis after surgical treatment of MLKIs. This suggests that the underlying mechanisms may be biological and/or socioeconomic in nature. The comparison of physical therapy utilization among those who underwent subsequent motion-restoring surgery after MLKI reveals the two patient subsets that we see clinically: those with stiffness secondary to arthrofibrosis and those with postoperative stiffness that may be secondary to underutilization or poor adherence to physical therapy. Both prior to and following the index MLKI procedure, significantly fewer patients who would later undergo motion-restoring surgery attended physical therapy. Additionally, significantly fewer patients in this subset had commercial insurance. This may point toward the development of postoperative stiffness due to underutilization or reduced access to physical therapy due to socioeconomic factors or other social determinants of health ,7,12,13.That said, the underlying mechanisms remain unknown but are theorized to be potentially related to a greater inflammatory response due to the increased severity of the injury, increased or persistent inflammation after MLKI reconstruction secondary to more involved surgical procedures, as well as prolonged immobilization that may be required to protect the reconstruction in the early postoperative period. Both the postoperative inflammatory response and rehabilitation protocols will likely differ based on the procedures performed and structures involved, and the primary goal of early postoperative rehabilitation must be to restore the range of motion without overstressing the involved tissues . WhetherCoding errors may have an impact on the results, as with all insurance claims database studies. Individual patient data are also not available, which limits the ability to perform multivariable regressions to assess risk factors for motion-restoring surgery after isolated ACL or MLKI reconstruction. Finally, the lack of a clear definition of arthrofibrosis and the variability in the indications for motion-restoring surgery have been well documented . Future The prevalence of motion-restoring surgery was significantly greater after MLKI when compared to an isolated ACL injury. While the etiology of arthrofibrosis after MLKI is likely complex, the current results suggest that demographic factors and physical therapy utilization are not solely responsible for the increased risk of arthrofibrosis after MLKI. The underlying mechanisms may then be biological and/or physiological in nature, thereby providing potentially modifiable treatment targets. Future work is necessary to elucidate whether the increased risk of arthrofibrosis for those with MLKIs is related to a greater inflammatory response due to the increased severity of the injury, increased or prolonged inflammation after MLKI reconstruction secondary to more involved surgical procedures, and/or prolonged immobilization that may be required to protect the reconstruction in the early postoperative period.


Lung herniation is a rare complication following cardiopulmonary resuscitation (CPR) and is defined as a protrusion of lung parenchyma through the thoracic wall. This article presents a case in which a patient presented to the hospital with sepsis secondary to community-acquired pneumonia. A 74-year-old female with a background of chronic obstructive pulmonary disease (COPD) suffered a sudden pulseless electrical activity (PEA) cardiac arrest while being managed in the acute medical ward. The CT following the return of spontaneous circulation (ROSC) demonstrated multiple bilateral anterior rib fractures and herniation of the right lung through the right lateral thoracic wall. She was managed in the ICU with ventilatory and cardiovascular support for four days until she suffered a second cardiac arrest, where resuscitation was unsuccessful. In addition to this case report, a literature review was carried out, given the rarity of this pathology. The literature provides only 13 articles on lung herniation due to CPR. The most common injury pattern was anterior rib fractures leading to anterior lung herniation. In our case report, the herniation was away from the fracture site at the lateral chest wall. A common complication was surgical emphysema in several of the articles, as was in our case. The surgical intervention appears to be indicated in large hernias, incarceration, or those causing pain and respiratory compromise. In our case, conservative management was elected, given the patient’s significant persistent cardiovascular instability unsuitable for interhospital transfer. A high index of suspicion should be adopted for patients who undergo a prolonged period of CPR, including frail patients with underlying health conditions such as chronic lung disease. Lung herniation is a rare complication of cardiopulmonary resuscitation (CPR). It is defined as a protrusion of lung parenchyma through the thoracic wall and is classified according to location and etiology ,2. It isA 74-year-old female presented to the acute medical unit (AMU) with 24 hours of worsening dyspnea and productive cough. She was an ex-smoker with a 40-50 years smoking history and chronic obstructive pulmonary disease (COPD). She suffered a deterioration in her respiratory function over the preceding two years, requiring triple therapy inhalers  and having received multiple acute courses of antibiotics and steroids in the community for infective exacerbations of COPD (IECOPD). She was reportedly independent in the community, and her past medical history included osteoporosis, a known aortic aneurysm, non-alcoholic fatty liver disease (NAFLD), and gallstones.Physical examination revealed a new oxygen requirement with oxygen saturations of 82% on room air, tachycardia, and pyrexia with stable blood pressure. Initial management for IECOPD was commenced and escalated to full sepsis protocol due to ongoing deterioration in the form of increasing oxygen requirements and persistent tachycardia.After 10 hours into her admission, she suddenly collapsed into PEA cardiac arrest. Immediate CPR following advanced life support (ALS) protocol was commenced. With high-quality manual CPR administered by trained staff throughout and 4x adrenaline (10ml of 1:10000 IV) given, return of spontaneous circulation (ROSC) was achieved after 29 minutes of arrest time. Bedside echocardiogram and chest X-ray at this time were unremarkable. Arterial blood gas demonstrated a metabolic acidosis with type 2 respiratory failure. She was transferred to the ICU for standard post-cardiac arrest care, including intubation, ventilation, sedation, and required inotropes for cardiovascular support.Owing to the sudden collapse, she underwent diagnostic imaging, including CT of the head, chest, and abdomen, to rule out pulmonary embolism and intracranial hemorrhage as a cause for cardiac arrest and establish the source of sepsis. This demonstrated right lower, middle, and upper lobe consolidation with bi-basal atelectasis, a likely source of sepsis. Multiple bilateral anterior rib fractures, in keeping with CPR, and herniation of the right lung through the right lateral thoracic wall were noted Figures -2. High-She required a ventilator and cardiovascular support throughout her ICU admission and remained sedated with propofol and alfentanil. Significant chest wall bruising to the anterior and right lateral chest was noted, with a small palpable mass and some surgical emphysema at the right lateral wall over the site of the herniation. While primary rib fixation was discussed, her pivotal problem was persistent cardiovascular instability, and she remained too clinically unstable for safe interhospital transfer for surgical intervention. Neurology remained poor despite weaning sedation. There was no requirement for renal replacement therapy. Broad-spectrum antibiotics were continued for sepsis. She suffered a second cardiac arrest four days into her ICU admission due to persistent cardiovascular instability and multi-organ failure. Despite CPR and maximal medical support, this was a terminal event.Literature reviewLung herniation following CPR is a rare event. Using the search terms ‘cardiopulmonary resuscitation,’ ‘CPR,’ ‘lung herniation,’ and‘ pulmonary herniation’ across Ovid, EMBASE, and PubMed search engines, 13 articles and case studies have been recorded prior to this report. Detailed results of the literature review are presented in Table Multiple rib fractures and sternal fractures are common resulting features after CPR, with up to 97% and 43% of people affected, respectively . DespiteLung herniation remains a rare complication of CPR. A high index of clinical suspicion should be present in those who underwent an extended period of CPR and in the frail with underlying health conditions. CT is the best modality for diagnosing lung herniation and has been shown to have the highest detection rate for CPR-related injuries. Given the emphasis on high-quality CPR and the use of mechanical chest compression devices in an aging population, clinicians need to be aware of this rare event, as timely recognition and management may improve survival.


Antioxidant supplements significantly increased both the maximum walking  and initial claudication  distances. The dietary interventions did not improve the physical function domain of the Short Form-36 , ABI or risk of adverse events, mortality, revascularisation or amputation. Dietary NO upregulators, especially antioxidants, appear to improve the initial claudication distance in patients with PAD. Larger high-quality RCTs are needed to fully examine the benefits and risks of these treatments. PROSPERO Registration: CRD42022256653.This systematic review pooled evidence from randomised controlled trials (RCTs) on the effectiveness of dietary upregulators of nitric oxide (NO) in improving the walking and quality of life of patients with peripheral artery disease (PAD). RCTs examining the effect of dietary upregulators of NO in patients with PAD were included. The primary outcome was the maximum walking distance. Secondary outcomes were the initial claudication distance, the six-minute walking distance, quality of life, the ankle-brachial pressure index (ABI), adverse events and risk of mortality, revascularisation or amputation. Meta-analyses were performed using random effects models. The risk of bias was assessed using Cochrane’s ROB-2 tool. Leave-one-out and subgroup analyses were conducted to assess the effect of individual studies, the risk of bias and intervention type on pooled estimates. Thirty-four RCTs involving 3472 participants were included. Seven trials tested NO donors, nineteen tested antioxidants, three tested NO synthase inducers and five tested enhancers of NO availability. Overall, the dietary supplements significantly improved the initial claudication (SMD 0.34; 95%CI 0.04, 0.64;  The most well-recognised symptom of peripheral artery disease (PAD) is intermittent claudication, which leads to a reduced walking ability, an impaired health-related quality of life and reduced physical activity, contributing to functional decline and an increased risk of major adverse cardiovascular events ,2. WhilePAD is associated with microvascular dysfunction resulting from impaired production and bioavailability of nitric oxide (NO) . NO reguThere are four main methods by which a dietary intervention might upregulate NO . During It is currently unclear whether dietary supplements aimed to upregulate NO are effective for treating PAD, with no consensus in practice guidelines ,24,25. TThis systematic review was performed according to the Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) statement  and regiThe primary outcome was maximum walking distance in a treadmill test. Secondary outcomes included initial claudication distance in either a treadmill test or corridor walking test, six-minute walking distance, quality of life assessed by validated tools including the Short Form (SF)-36 and Walking Impairment Questionnaire (WIQ), ABI and safety outcomes, including total adverse events, total serious adverse events, mortality and requirement for surgical or endovascular revascularisation or amputation. Adverse events were defined as any unintended and unfavourable sign or symptom temporally associated with the use of the intervention. Adverse events were considered serious if they resulted in mortality, threat to life, inpatient hospitalisation or prolongation of hospital stay or disruption of the ability to conduct normal activities of daily living. Other data extracted included age, sex, smoking, diabetes, inclusion and exclusion criteria, descriptions of intervention and control, assessments of adherence, follow-up duration and loss to follow-up. Loss to follow-up was defined as study participants for whom primary outcome data were not reported. Intention-to-treat results were used for the meta-analyses, where available. Missing data were to be resolved first by contacting the primary study investigators for unreported data, and then if unsuccessful, by imputation . Data weRisk of bias was assessed independently by two reviewers (S.A.W. and A.D.) using version 2 of the Cochrane risk of bias tool (ROB-2) . Any disp-values < 0.05 were considered significant. Statistical heterogeneity was assessed using the I2 statistic and interpreted as low (0 to 49%), moderate (50 to 74%) or high (75 to 100%). Subgroup meta-analyses were conducted to assess the impact of risk of bias, specific types of dietary interventions and testing the primary outcome using fixed effects rather than a random effects model if there were at least two studies for any outcome measure. Leave-one-out (LOO) sensitivity analyses were performed to assess the contribution of each study to the effect estimates by excluding individual studies and recalculating the pooled estimates. Funnel plots comparing the summary estimate of each study and its precision (1/standard error) were used to assess publication bias [Data for all primary and secondary outcomes were synthesised in meta-analyses if data were reported for at least three trials. Meta-analyses were performed using the inverse variance method for continuous outcomes and Mantel–Haenszel’s statistical method for dichotomous outcomes with random effect models anticipating substantial heterogeneity. The results were reported as standardised mean differences (SMD) or odds ratios (OR) and 95% confidence intervals (CI). SMDs were interpreted as Cohen’s d values, with d = 0.2 regarded as a “small” effect size, d = 0.5 as a “medium” effect size and d = 0.8 as a “large” effect size. All statistical tests were two-sided and ion bias . All anaion bias .n = 1619) or control groups (n = 1853)  . Sample  = 1853) .The dietary interventions tested were diverse and spanned the four different categories as described in Overall, 10 trials were deemed as low risk of bias, 20 as some risk of bias and 5 as high risk of bias . The domEach trial reported on a varying number of outcomes .n = 1057; control n = 1020) found that the dietary interventions had a small positive effect on maximum walking distance, but CIs crossed 0 . There was a statistically significant improvement in the maximum walking distance in the intervention group compared to control when using fixed effect  instead of random effect models  found that the initial claudication distance was significantly improved by dietary interventions . The funnel plot was asymmetrical  showed that dietary interventions did not have any effect on the 6-min walking distance . The funnel plot was symmetrical  found that the physical function domain in the SF-36 was slightly decreased in the dietary intervention group , but this finding did not reach statistical significance. LOO sensitivity analyses suggested that removal of the Goldenberg 2012 trial [A meta-analysis of six trials  demonstrated no significant effect of the dietary interventions on the perceived walking distance . The funnel plot was symmetrical  demonstrated no significant impact of the dietary interventions on the perceived walking speed . The funnel plot was asymmetrical  found that dietary interventions moderately improved the participants’ ABI when compared to control, though this increase was not statistically significant  found that dietary interventions increased the participants’ risk of adverse events, though this increase was not statistically significant . The funnel plot was asymmetrical  demonstrated that dietary interventions slightly decreased the participants’ risk of serious adverse events , but this finding was not statistically significant. The funnel plot was asymmetrical  found that dietary interventions had little effect on mortality . The funnel plot was symmetrical  showed that dietary interventions had no significant effect on requirement of lower extremity revascularisation or amputation . The funnel plot was asymmetrical (A meta-analysis of six trials (intervention metrical . LOO senmetrical . There wThis meta-analysis demonstrated that dietary interventions that upregulate the NO pathway moderately improved the initial claudication distance in patients with PAD, but the improvements in the maximum walking distance did not achieve statistical significance. The interventions classified as antioxidants had the greatest effect on walking distance. Quality of life, ABI and safety outcomes did not differ significantly between intervention and control groups.Both the initial claudication and maximum walking distance on treadmill testing have been proposed as accurate measures of walking impairment in patients with PAD, although this remains controversial ,68. Few Antioxidants are known to protect against oxygen-free radicals and other toxic metabolites produced in ischemia and tissue damage  to enhanInterestingly, the studies with “some risk” of bias demonstrated greater effect estimates than those deemed “low risk” or “high risk”. Out of these studies, the ones that reported a significant effect of the intervention on maximum walking distance or initial claudication distance were mostly judged to have “some risk” of bias due to potential bias in the randomisation process or selection of reported results. These judgments were only due to a lack of information reported about the randomisation process or a pre-specified analysis plan, and not due to baseline differences between groups or issues with blinding or allocation concealment. Thus, the results of these studies demonstrating a positive effect of dietary nitrate interventions on the walking performance should not be dismissed. In addition, random-effects modelling reduces the effect of study size on the weightings of each study. A sub-analysis found that the primary outcome of maximum walking distance was significantly improved when using a fixed effect model, highlighting the need for larger high-quality trials.The strengths of this systematic review include a pre-specified analysis plan, an extensive risk of bias assessment and reporting of sensitivity and subgroup analyses to evaluate the effects of individual studies, intervention types and risk of bias on pooled outcomes. There were several limitations to this meta-analysis. Firstly, there was significant heterogeneity amongst the included studies in terms of the interventions used and the study designs, populations and outcome assessments, which was reflected in the marked statistical heterogeneity for most outcomes. Although subgroup analyses were used to elucidate the most effective intervention types, these also had marked statistical heterogeneity. Most funnel plots suggested a risk of publication bias, and thus possible over-estimation of the interventions’ effects on the reported outcomes. Some of the LOO sensitivity analyses demonstrated the presence of outliers that could have skewed the results. Finally, meta-analyses of quality of life, ABI and safety outcomes were limited due to under-reporting.This meta-analysis suggests that dietary interventions that upregulate NO may improve the initial claudication distance in patients with PAD. Antioxidant supplements, specifically L-carnitine and its derivatives, appeared to be the most effective interventions, and thus warrant further investigation. It remains unclear whether dietary supplements to upregulate NO influence patients’ quality of life, ABI or safety outcomes. Due to heterogeneity, risk of bias and inconsistent findings, further large and methodologically rigorous RCTs are needed to resolve the benefit of dietary NO upregulation and particularly antioxidants.


A 45-year-old male in a hypertensive emergency was admitted with complaints of frontal headache, progressive chest discomfort, shortness of breath, dysphagia, and right upper quadrant abdominal pain radiating across the epigastrium and to the back that increases in intensity with deep inspiration. He denied any history of abdominal pain, vomiting, dyspnea, nausea, and weight loss. A computed tomography (CT) scan of the chest showed a posterior mediastinal mass between the esophagus and descending aorta. A magnetic resonance imaging (MRI) scan revealed a non-enhancing posterior mediastinal mass possibly compressing both the esophagus and the airway. A 30-degree thoracoscope was inserted in the chest cavity revealing a large hemothorax from a possibly ruptured inflammatory myofibroblastic tumor (IMT) encompassing nearly the entire pleural space with both fresh and clotted blood. Two liters of fresh blood was removed via a right thoracotomy procedure. Once removed, a large fibrinous clot-filled mass was resected entirely and sent to pathology. Postoperative recovery was uneventful; dysphagia and shortness of breath resolved. The patient gradually resumed his regular diet. Inflammatory myofibroblastic tumors (IMTs) are complexes of myofibroblastic spindle cells that demonstrate an inflammatory infiltrate. Though these rare lesions can arise from any tissues in the human body, their development in the mediastinal region is very uncommon. Histologically, IMTs exhibit diverse appearances, ranging from fibroblastic and myofibroblastic proliferation to an inflammatory infiltrate rich in plasma cells, lymphocytes, and eosinophils . DiagnosA 45-year-old male presented in the emergency department in a hypertensive emergency 234/131) with complaints of frontal headache, progressive chest discomfort, shortness of breath, dysphagia, and right upper quadrant abdominal pain radiating across the epigastrium and to the back that increases in intensity with deep inspiration. He has a past medical history of asthma and obstructive sleep apnea on continuous positive airway pressure (CPAP) and has not been to a doctor's visit in over six years. A computed tomography (CT) scan of the chest was completed due to concerns of possibly ruptured posterior mediastinal mass versus mass effect with pleural effusion. A computed tomography (CT) scan in Figure 31 with cUpon the review of physical evaluation and imaging, surgical intervention was advised. Chest X-ray (CXR) result showed decreased right-sided consolidation and effusion compared with previous studies Figure .The thoracic team was consulted to proceed with elective thoracotomy, which confirmed a massive right hemothorax Figure . A diagnUpon the evacuation of the hemothorax and the stabilization of the bleeding, the fibrinous clot  was carefully removed from the cystic structure and sent to pathology. The underlying esophagus was identified in this region and appeared to have both acute and chronic inflammation in this region. The cyst wall appeared to be occupying the outer layer of the esophagus and was not removed. A portion of the lateral cyst wall was removed however adjacent to the aorta and sent to the laboratory for pathology analysis. Figure Histopathologic examinationThe histological examination revealed distinctive features of the tumor, including elongated nuclei and eosinophilic cytoplasm, composed of spindle-shaped cells. These cells were observed alongside a notable mixed lymphoplasmacytic inflammation. The lesion lacked significant nuclear pleomorphism and showed a brisk mitotic activity. Immunohistochemically, the tumor tested positive for smooth muscle actin (SMA), desmin, caldesmon, and activin receptor-like kinase 1 (ALK1). Conversely, myogenin staining was negative, ultimately confirming the diagnosis of an inflammatory myofibroblastic tumor as shown in Figure Inflammatory myofibroblastic tumors (IMTs) were first reported in the late 1930s as lesions of myofibroblastic spindle cells and infiltrates of lymphocytes, plasma cells, and eosinophils , while oThe diagnosis of such tumors prior to symptom presentation is very difficult as symptoms may go overlooked by patients as simple discomfort. Our patient presented with progressive dysphagia and shortness of breath along with vital signs of hypertensive emergency. Even when symptoms are reported by patients, approximately 6.3% of IMT cases are discovered via biopsy alone [In summary, we have presented an exceptionally rare occurrence of massive hemothorax attributed to the rupture of an inflammatory myofibroblastic tumor (IMT) located within the right thoracic cavity. While IMTs are infrequently encountered within the mediastinum of the general population, our report underscores the importance of considering IMT as a differential diagnosis when patients present with progressive dysphagia. This case serves as a poignant reminder of the intricate array of medical conditions that can manifest within the human body and emphasizes the necessity of maintaining a comprehensive differential diagnosis approach, especially in cases with atypical presentations. The management of hemothorax due to IMT rupture necessitates a multidisciplinary approach and collaboration in achieving an accurate diagnosis and implementing a tailored treatment plan.


A 75-year-old woman presented to our eye clinic with sudden loss in vision in the right eye. She had started nivolumab monotherapy 10 days before the onset of symptoms for the treatment of melanoma. Examination showed low visual acuity (20/170) in the right eye with few reactive cells and macular oedema and swelling in the anterior and posterior segments, respectively. Optical coherence tomography (OCT) of the right eye showed intra-retinal and sub-retinal fluid and multiple hyperreflective inner retinal round foci in the areas of inflammation. The differential diagnoses were infectious uveitis, Vogt-Koyanagi-Harada-like syndrome or masquerade retinopathy. After a full work-up, the patient was diagnosed with unilateral posterior uveitis. The patient responded to topical steroid therapy with improved vision (20/30). Uveitis is listed as an adverse effect on the prescribing list of the drug Opdivo®. Although not reported before, our case demonstrated unilateral involvement. We thus recommend clinicians to be wary after complaints of side effects from their patients; ocular toxicities should be considered.Patients using immunotherapies like immune checkpoint inhibitors (ICIs) can develop ocular immune-related adverse effects (irAEs). Nivolumab (Opdivo Immunotherapies in the form of immune checkpoint inhibitors (ICIs) have been developed to treat many malignancies, including melanoma, and squamous cell carcinoma, amongst others . ClinicaThis article was previously presented as a poster at the Royal Society of Medicine Ophthalmology trainee and student prize meeting 2023 on June 15, 2023.A 75-year-old woman came to our eye clinic due to rapid deterioration in vision in the right eye; she denies any discomfort, trauma, or other symptoms. In her medical history, she reports having started nivolumab monotherapy to treat metastatic cutaneous melanoma (stage III) without cerebral or ocular metastatic involvement 10 days before ocular symptoms emerged.On examination, we found the patient’s visual acuity was 20/170 on the right and 20/30 on the left. Anterior segment examination of the right eye revealed few reactive cells (Grade +0.5). The cornea and conjunctiva were unremarkable. The patient had bilateral reduced retinal pigmentation, in keeping with physiological variation. The right eye revealed macular oedema and optic disc swelling, with associated inflammatory cells infiltrating the vitreous (Grade +1) -Angiography imaging. OCT examination can be seen in Figure Given the history of immunotherapy and the unilateral nature of the presentation, we were most concerned with the possibility of infectious uveitis, Vogt-Koyanagi-Harada-like syndrome or masquerade retinopathy.The normal retinal pigment epithelium contour and negative findings on serological and radiological testing suggested sterile inflammation due to immunotherapy prompting the accurate diagnosis of unilateral posterior uveitis.The patient was prescribed g. dexamethasone 0.1% preservative-free hourly for two days, then every two hours for two days, then six times a day for seven days, then to reduce one drop per week until cessation. Following the intensive therapy with slow tapering, the vision improved to 20/30 Figures .Nivolumab , is a human programmed cell death-1 (PD-1) IgG4 monoclonal antibody inhibitor . In cancUveitis is listed as an adverse effect on the prescribing list of the drug Opdivo® . Cases oThe use of topical steroids for the posterior uveitis of our patient was appropriate and followed the efficacy seen in bilateral uveitis cases secondary to nivolumab administration ,6. It isReports of adverse effects from nivolumab use are emerging, including bilateral uveitis and panuveitis, with unilateral posterior uveitis being a rare irAE seen in patients with aggressive melanomas treated with nivolumab. It is particularly devastating for cancer survivor patients to lose their eyesight after that. We thus recommend that clinicians be aware that ocular toxicities should be considered after the complaint of side effects from their patients. Thereby, referral for eye screening after any irAEs is crucial to ensure early detection and appropriate management of these complications.Like immunotherapy drugs, novel cancer therapy can cause irAEs. The onset of ocular side effects can start as early as a few weeks after the initiation of drugs. Patients should be counselled about the potential implication of their vision and offered a complete ocular examination in cases of eye-related complaints following the initiation of immunotherapies.


Oral health needs assessment is important for oral health care planning. This study compared dental treatment needs between normative and sociodental needs. We also longitudinally examined the relationships of baseline sociodental needs measures and socioeconomic status with one-year follow up measures of use of dental services, dental caries, filled teeth, and oral health-related quality of life (OHRQoL).11 − 14) and behaviours . Normative need was assessed according to decayed teeth, clinical consequences of untreated dental caries, malocclusion, dental trauma, and dental calculus. The relationships between variables were tested thorough Structural equation modelling.A prospective study was conducted with 12-year-old adolescents from public schools in deprived communities in the city of Manaus, Brazil. Validated questionnaires were used to collect adolescents’ sex and socioeconomic status, OHRQoL (CPQOverall 95.5% of adolescents had normative dental treatment needs. Of these, 9.4% were classified as high level of propensity. Higher normative/impact need and greater propensity-related need directly predicted use of dental services at one-year follow up. The latter mediated the association of normative/impact need and propensity-related need with incidence of dental caries and filled teeth. Normative/impact need and use of dental services were directly associated with filled teeth at one-year follow up. Poor OHRQoL at one-year follow-up was directly predicted by higher normative/impact need at baseline and less filled teeth at one-year follow up. Greater socioeconomic status was directly associated with better propensity-related need. Socioeconomic status indirectly predicted incidence of dental caries and filled teeth via propensity-related need and use of dental services.Sociodental needs measures were related to use of dental services, dental caries, filled teeth and OHRQoL after one year among adolescents living in deprived communities. Adolescents with dental needs treatment priorities according to the sociodental approach had more filled teeth via use of dental services. Dental services utilisation did not attenuate the impact of normative and impact-related need on dental caries incidence and poor OHRQoL after one year. Our findings suggest the importance of developing oral health promotion and enhancing access to dental care to improve oral health of adolescents living in deprived communities.The online version contains supplementary material available at 10.1186/s12913-023-09596-0. The assessment of population oral health needs represents the basis for oral health care planning through providing relevant information for costs estimation, rational allocation of healthcare services and dental treatment expenses , 2. DespThe common assumption in the organization and provision of dental care that the need for treatment should be normatively determined by dentists has been criticized. Essentially, oral health needs assessment should extend beyond the narrow and limited clinical interpretation of dental conditions. Other relevant factors, such as subjective perception of oral health and dental needs, individual behaviours, impact of oral health conditions on daily life and well-being, and social inequalities, should also be considered in dental care planning . In addiIn this context, the sociodental approach was developed as a new conceptual model to improve the current approaches of oral health needs assessment at population level , 2, 8. TThe main purpose of the sociodental needs models is to overcome the limitations of using only normative measures for planning the provision of oral health care services through identifying and prioritizing those individuals who would most benefit from dental treatment , 2. PrevTo date, the sociodental needs assessment was predominantly tested through cross-sectional studies as a framework for assessing dental needs. Thus, it remains unclear whether combining normative need, impact-related need and propensity-related need would influence use of dental services, dental clinical measures and OHRQoL over time. Longitudinal studies testing the sociodental approach of dental treatment needs can contribute to enhance the understanding of its application and utility in public oral health care services. Therefore, the aims of the present study are to compare the dental treatment needs between normative and sociodental dental needs models among 12-year-old adolescents living in deprived communities. Moreover, this study also evaluate the relationships of baseline sociodental needs measures and socioeconomic status with one-year follow up measures of use of dental services, dental caries, filled teeth, and OHRQoL. It was hypothesized a priori that adolescents with greater sociodental needs and higher propensity-needs at baseline are more likely to use dental services, have lower incidence of dental caries, more filled teeth and poor OHRQoL after one year of follow-up.A one-year prospective longitudinal study was carried out in deprived communities in the eastern zone of the city of Manaus, Brazil, which has the poorest social indicators of the city . Inclusion criteria were adolescents enrolled in one of the selected public schools and age equal to 12 years. Exclusion criteria were adolescents in need of special care, with diagnosis of any syndrome and those using orthodontic appliances.A representative sample of 12-year-old adolescents enrolled in the 7th grade of municipal public schools was selected through stratified random sampling according to the size of the school population in the 11 districts of the city. Initially, twenty-five schools were randomly selected, proportional to the number of schools per neighbourhood. Thereafter, all students aged 12 years in the 7th grade from all classes of the selected schools were invited to participate. The multilevel structure of the data was assessed through testing the variance and standard error of null multi-level models considering school as a second-level variable. The variation of use of dental services at one-year follow up (P = 0.335), dental caries incidence at one-year follow up (P = 0.999), filled teeth incidence at one-year follow up (P = 0.712), and OHRQoL at one-year follow up (P = 0.575) were not statistically significant. Therefore, multilevel analysis accounting for school-level was not conducted.Initially, 528 adolescents were invited to participate. Of them, 86 did not return the consent form or their parents did not agree with their participation, resulting in a sample 442 adolescents (baseline response rate = 76%). Twenty-seven adolescents were excluded due to the use of orthodontic appliances. Thus, the sample size at baseline included 415 adolescents. One-year follow-up data collection involved 334 adolescents, respectively (retention rate = 80.5%). A study with 334 participants would lend a power of 90% to estimate a structural equation model involving 5 observed variables and 2 latent variables considering a significance level of 5% and significant effects of 0.19 .Adolescents completed self-administered questionnaires in 2016 to collect baseline data on sex, OHRQoL and oral health-related behaviours, including sugar intake, frequency of toothbrushing, and regular use of fluoridated toothpaste. Baseline information on socioeconomic status and pattern of dental attendance were collected from their parents/guardians using structured questionnaires.Clinical oral examinations were performed by nine trained and calibrated dentists, using dental plain mirror (Duflex ®) and a ball-end community periodontal index probe (Stainless ®) under natural light in a sitting position. All adolescents performed oral hygiene under supervision before dental examinations. Number of decayed teeth, number of filled teeth, clinical consequences of untreated dental caries, malocclusion, dental trauma, and dental calculus were registered at baseline. Use of dental services, OHRQoL, dental caries and filled teeth were also collected at one-year follow up. The data was collected in a private room in the schools.In this study, sociodental needs assessment was composed of NN, IRN and propensity-related need to test the DNLP and BMD models. Decayed teeth and clinical consequences of untreated dental caries were used in the DNLP model. Number of decayed permanent teeth and number of teeth with clinical consequences of untreated dental caries were evaluated using the decayed component of the Decayed, Missing and Filled Teeth Index (DMFT)  and the The BMDN applies to dental conditions that are less likely to progress or cause adverse health consequences in the absence of treatment . Maloccl11 − 14) impact short form for Brazilian population . The proportion of adolescents with a NN for dental treatment was 95.5%, of which 43.6% had dental needs life-threatening and progressive oral conditions (DNLP). Of these adolescents, 9.4% had high behavioural propensity and would be able to undergo immediate dental treatment. The remaining 34.2% with low or medium behavioural propensity could receive education and/or oral health promotion (DHE/OHP) along with clinical treatment. Of the 56.4% adolescents within the basic model of dental needs (BMDN), 28.2% did not have oral impacts and 28.2% had their quality of life affected by oral conditions. Of these, 4.1% had high behavioural propensity-related need and should be treated as initially planned. The remaining 24.1% adolescents with BMD and oral impacts had medium or low behavioural propensity and would need DHE/OHP [see Additional file The measurement model was assessed using confirmatory factor analysis for the latent variables socioeconomic status, OHRQoL at baseline and OHRQoL at one-year follow up. The items that confirmed the latent variable socioeconomic status were monthly family income (β = 0.690), house crowding β= -0.277) and number of goods (β = 0.419). The item loadings confirming the latent variable OHRQoL at baseline were symptoms (β = 0.617), function (β = 0.749), emotional (β = 0.675) and social (β = 0.702) and OHRQoL at one-year follow up were symptoms (β = 0.588), function (β = 0.682), emotional (β = 0.656) and social (β = 0.701) .The direct and indirect relationships estimated in the parsimonious model are summarized in Fig. The present longitudinal study compared the dental treatment needs between normative need and the sociodental dental needs according to life-threatening and progressive oral conditions (DNLP) and basic model of dental needs (BMDN) in 12-year-old adolescents from families living in deprived communities in Brazil. In addition, the influence of sociodental system of dental needs assessment on use of dental services, dental clinical outcomes and OHRQoL over one year of follow up was also investigated.The substantial decrease of the sociodental approach in the estimates of treatment needs from 95.5% (normative need) to 13.5% (high propensity-related need) is a confirmatory finding. Although almost half of the adolescents 43.6%) had DNLP and would require immediate dental treatment, nearly 10% had high behavioural propensity and thus would be able to efficiently benefit from treatments. These findings are consistent with previous studies that suggested that normative methods of needs assessment overestimate the proportion of subjects in need of dental treatment than the sociodental approach , 6–11. H% had DNLThe present findings partially confirmed the influence of sociodental needs approach on use of dental services and oral health measures of adolescents living in deprived communities. Adolescents with greater treatment needs according to normative need and impact-related need and those with higher behavioural propensity at baseline were more likely to use dental services and receive more restorative treatments over one-year period. Therefore, our findings support the importance of incorporating subjective and social measures in the assessment of oral health needs since the sociodental approach predicted dental visits and treatment for dental caries. Use of dental services can be influenced by demographic and socioeconomic factors related to general and oral health , 22. TheUse of dental services was a meaningful variable in this study since greater sociodental needs and higher behavioural propensity were associated with higher incidence of dental caries and filled teeth mediated by use of dental services. The possible positive influence of use of dental services on OHRQoL was not observed in the present study. So, the potential benefits of dental visits on preventing dental caries and improving OHRQoL were not confirmed. The use of dental services failed to prevent dental caries, suggesting that attending dental visits are not sufficient to reduce the development of new dental caries lesions in adolescents who are also at greater risk of future caries . A recenBehavioural propensity was directly related to use of dental services and indirectly associated with incidence of filled teeth. The association between oral health behaviours and use of dental services was reported by another study that emphasized the importance of adopting healthy behaviours among children and adolescents as they can determine the pattern of oral diseases in the near future . In the The use of structural equation modelling was a robust analytical method to test the hypotheses of theoretical model, and to explore the simultaneous relationships between the variables related to the sociodental system of dental needs assessment, socioeconomic status, use of dental services, dental caries and OHRQoL over one year of follow up. Furthermore, the longitudinal design of this study supports the interpretation of the temporal relationships between variables. Nonetheless, some limitations must be acknowledged. First, only 12-year-old adolescents living in social deprivation were included. So, the generalization of our findings to other age groups and adolescents from different socioeconomic backgrounds must be carefully proceeded. Second, oral health behaviours were assessed only at baseline and some participants may have changed the investigated behaviours during the study period. Third, other potential predictors of dental services utilization, dental caries and OHRQoL, such as parental practices and psychosocial factors, were not analyzed in this study. Finally, relevant information related to use of dental services at one-year follow up, such as the reason for dental visit and the types of dental treatments received during the follow up were not assessed.The longitudinal evaluation of the sociodental approach on use of dental services, dental caries incidence and OHRQoL demonstrated that normative need combined with impact-related need and propensity-related need can provided a sound strategy for oral health treatment planning. Our findings also suggest that use of dental services was a relevant factor by which the sociodental needs and behavioural propensity impact on oral health afterwards. Access only to dental care in deprived communities resulted in more filled teeth but did not prevent future lesions of dental caries and did not improve OHRQoL.Future interventional studies are necessary to evaluate the acceptability of the sociodental approach for delivering oral health care as well as the benefits of the sociodental system to improve adolescents’ dental clinical measures and subjective oral health. Investigations on the impact of oral health education and/or health promotion programs on behavioural propensity and oral health outcomes are also needed.Below is the link to the electronic supplementary material.Supplementary Material 1


Giardia duodenalis  is a widespread gastrointestinal protozoan parasite with debated taxonomic status. Currently, eight distinct genetic sub-groups, termed assemblages A–H, are defined based on a few genetic markers. Assemblages A and B may represent distinct species and are both of human public health relevance. Genomic studies are scarce and the few reference genomes available, in particular for assemblage B, are insufficient for adequate comparative genomics. Here, by combining long- and short-read sequences generated by PacBio and Illumina sequencing technologies, we provide nine annotated genome sequences for reference from new clinical isolates (four assemblage A and five assemblage B parasite isolates). Isolates chosen represent the currently accepted classification of sub-assemblages AI, AII, BIII and BIV. Synteny over the whole genome was generally high, but we report chromosome-level translocations as a feature that distinguishes assemblage A from B parasites. Orthologue gene group analysis was used to define gene content differences between assemblage A and B and to contribute a gene-set-based operational definition of respective taxonomic units. Giardia is tetraploid, and high allelic sequence heterogeneity (ASH) for assemblage B vs. assemblage A has been observed so far. Noteworthy, here we report an extremely low ASH (0.002%) for one of the assemblage B isolates . This challenges the view of low ASH being a notable feature that distinguishes assemblage A from B parasites, and low ASH allowed assembly of the most contiguous assemblage B genome currently available for reference. In conclusion, the description of nine highly contiguous genome assemblies of new isolates of G. duodenalis assemblage A and B adds to our understanding of the genomics and species population structure of this widespread zoonotic parasite. Software tools used in the study are publicly available and the sources have been provided within the article.Raw reads produced within this project are deposited at the NCBI SRA database under BioProject accession number PRJNA879307 and available at Giardia duodenalis is a widespread protozoan parasite relevant for public health. The lack of high-quality genome assemblies for reference has hampered population genetic studies. Here, for reference we provide nine highly contiguous annotated genome assemblies of the two assemblage types A and B that derive from eight human clinical isolates and one cat isolate. Despite the high overall genomic synteny between assemblage A and B, there are specific genome rearrangements and orthologous gene groups that distinguish and classify the assemblages. Strikingly, the genome of one of the assemblage B isolates was characterized by an extremely low allelic sequence heterozygosity (0.002%), resulting in the most contiguous assemblage B genome described to date. Overall, the described genomes add a significant resource to the very few available Giardia genomes  that can be exploited to illuminate the impact of genetic differences on poorly understood factors mediating disease manifestation or virulence, zoonotic potential and taxonomy.Giardia duodenalis  is one of the most commonly diagnosed intestinal protozoan parasites worldwide and a significant public health concern. Transmission occurs via infectious cysts by the faecal–oral route, either directly by contact with another infected host  or indirectly by uptake of cyst-contaminated food or water. Infection is often asymptomatic or causes variable symptoms such as diarrhoea, nausea and other unspecific gastrointestinal complaints. Infections are mostly self-limiting, but chronic infections are also observed ; three assemblage AII ; and two assemblage B [GS (three different data sets) and BAH15c1]. Each of these eight isolates was derived originally from humans. In addition, one genomic data set of a pig assemblage E isolate (P15) is publicly available . For nomblage A . Recentlssembled . The mosssembled . Equivalssembled  are the Difficulties in retrieving high-quality genome data for assemblage B parasites may in part result from allelic sequence heterozygosity (ASH), which poses a formidable challenge for assembly routines depending on sequencing technology. ASH in the assemblage B isolate GS reference genome is about 20-fold higher than in assemblage A based on the current reference genome of WB6 where ASH affects only 0.03 % of sites . The larG. duodenalis by a hybrid PacBio/Illumina sequencing approach of four new assemblage A  and five new assemblage B isolates (from humans) derived by axenic culture from clinical samples. As result, we provide nine highly contiguous genome assemblies of new isolates of G. duodenalis assemblage A and B. In particular, we provide assembly of the most contiguous assemblage B genome currently available to be used for reference purposes.Here, we addressed the lack of high-quality genome data sets for G. duodenalis trophozoites were grown in TYI-S-33 medium containing bovine serum as previously described .d-gluconic acid reductases and carboxymuconolactone decarboxylase and lactonases have been reported to differentiate assemblage B from A genomes [d-gluconic acid or non-family 1 aldo-/keto reductase function were present in assemblage B genomes but absent in assemblage A genomes.Besides members of these large gene families, orthologues assigned known specific functions such as enzymatic activities present in one but not the other assemblage were also observed. Genes encoding arginases, 2,5-diketo- genomes . Here, aGiardia genomes confirmed the representation of large gene families in Giardia assemblage A and B and revealed core and assemblage/isolate-specific orthologue proteins that will help to decipher biological differences.Taken together, genome annotation in the newly assembled G. duodenalis isolates, including eight clinical human samples and one cat sample, which addresses a significant knowledge gap. The new genomes represent a sampling of the major human-pathogenic parasite (sub-)assemblages AI, AII and B as shown by assembly-free phylogenetic analyses. Predicted size, gene content and general features of the genomes corroborate currently available reference genome data. High-quality assemblage B genomes have been a resource much desired in this field. Our genome assemblies show low fragmentation comparable to the most advanced assemblage AI-type reference genome of isolate WB6.We report highly contiguous genomic sequences and respective assemblies for nine G. duodenalis is composed of eight genetically distinct assemblages or whether the term ‘assemblage’ is a misnomer for a collection of separate species historically defined based on host range [It is of debate whether st range . The first range  with itsst range . Our newst range  to suppost range  and is nTo the best of our knowledge, the assembly of isolate P424 represents the first assemblage B near haplotype genome sequence. The observation that this genome has extremely low ASH in comparison to other available assemblage B isolate genome sequences challenges the current notion that a high ASH level is a distinctive characteristic of assemblage B. Of note, P424 is not a highly singular example but, based on recent data, belongs to a subpopulation of BIV isolates exhibiting significantly fewer ASH positions detectable by MLST . This hiGiardia isolates combining long-read sequences from MinIon instead of PacBio [Giardia, the latter appears more informative for the definition of gene content, as well as the pangenome, and core and accessory genomes.We used a hybrid approach combining long-read sequences generated by PacBio technology and short-read sequences by Illumina to build high-quality genome assemblies. A similar approach was recently applied to three different f PacBio . The autf PacBio . Our appGiardia and suggest distinguishable (tentative species-specific) pan genomes.Comparative analyses of the gene content of our new isolates to the reference genomes of WB6, DH and GS revealed that 53–65 % of genes encoded proteins with corresponding orthologues in all isolates. In contrast, the presence–absence variation segregated the A and B assemblages as well as the accessory genomes of (sub)-assemblages. As a whole, our data significantly extend the understanding of the core genome of the genus A blessing and a curse’ [Functional annotation is required for the interpretation and discussion of biological consequences of these genomic differences in gene content and presence–absence variation. Here, functional assignments refer to the respective annotations of the currently best annotated genome (i.e. that of WB6). However, general limitations of automated annotation approaches apply. Automated genome annotation though common practice has been highlighted as ‘a curse’ . Such auGiardia parasites is generally very low and may be prone to culture bias. As of today only assemblage A and B isolates and assemblage E can be successfully cultured axenically [Giardia isolate cultures are established by in vitro excystation and cultured as bulk populations (described in the very first publications), or isolated by cyst infection in rodents with recovery of trophozoites from animal small intestine [de novo assembly efficiency. However, for the selected assemblage BIII isolates, the recent analysis of the two nitroreductase genes by cloning of PCR products from the said isolates’ genomic DNA revealed more than four alleles. This indicates derivation of the lines from a possibly underlying mixed infection [Giardia, especially within assemblage B isolates. It should be noted that one early study using the assemblage AI (WB6) genome revealed that the minimal kinome of Giardia lost important kinases in comparison to other excavata, including ‘kinases involved in central biological functions, such as DNA repair, transcription, splicing, and mitochondrial metabolism’ [Giardia assemblage A parasites exchange genetic material between nuclei and may perform some sort of parasexual reproduction (diplomixis) [One major limitation of our study is that, against expectations, some of the cultured assemblage B isolates apparently do not represent clonal cell lines. Culture efficiency of enically . Typicalntestine . Clonal nfection . The latnfection . Therefoabolism’ . It is tabolism’ . Differelomixis) . Inter-nlomixis) . For assGiardia clinical isolates are standard and commonplace in the field. Second, we aim to draw attention to potential non-clonal isolates confounding forthcoming or existing Giardia genome datasets. The analytical approaches used here can aid in determining clonality in sequenced isolates. The ‘mixed’ genomes assembled well and are informative in aspects that are common features of assemblage B parasites, such as the apparent chromosomal rearrangement distinguishing assemblage A and B  compared to other eukaryotes . NEK proteins are associated with functional roles in mitosis and flagella formation [Giardia and is thought to mainly act as part of immune escape mechanisms and cell surface protection [The finding that assemblage A and B segregated based on presence–absence variation in genes predicted to encode metabolic enzymes such as arginase, or aldo-/ketolases complements observations reported recently based on comparative analysis of the s genome . It is a studies . For exa studies . The NEKormation . VSP/HC otection . The speG. duodenalis isolates that represent a sampling of the main human pathogenic assemblage types AI, AII and B. Overall structure and gene content confirms and significantly complements data from available genomes. The data contribute to the definition of pan, core and accessory genomes. Notably, the assemblage B isolate P424 sequence data represent a desired near-haplotype genome for this assemblage.In summary, hybrid sequencing data from long-read sequences by PacBio and short-read sequencing by Illumina technology allowed the generation of nine highly contiguous assemblies of genomes of tetraploid Click here for additional data file.Click here for additional data file.


Sc) of the host-encoded prion protein (PrPC). Prion replication stems from the capacity of PrPSc to self-replicate by templating PrPC conversion and polymerization. The question then arises about the molecular mechanisms of prion replication, host invasion, and capacity to contaminate other species. Studying these mechanisms has gained in recent years further complexity with evidence that PrPSc is a pleiomorphic protein. There is indeed compelling evidence for PrPSc structural heterogeneity at different scales: (i) within prion susceptible host populations with the existence of different strains with specific biological features due to different PrPSc conformers, (ii) within a single infected host with the co-propagation of different strains, and (iii) within a single strain with evidence for co-propagation of PrPSc assemblies differing in their secondary to quaternary structure. This review summarizes current knowledge of prion assembly heterogeneity, potential mechanisms of formation during the replication process, and importance when crossing the species barrier.Prions are proteinaceous pathogens responsible for a wide range of neurodegenerative diseases in animal and human. Prions are formed from misfolded, ß-sheet rich, and aggregated conformers (PrP Prion diseases are a group of expanding fatal, infectious, neurodegenerative disorders affecting humans and wild-life or farmed animals. These diseases include Creutzfeldt-Jakob disease (CJD) in humans, scrapie in sheep and goats, bovine spongiform encephalopathy (BSE) in cattle, and chronic wasting disease (CWD) in a wide range of cervids Collinge . Prion dPrions, the causative pathogens of prion diseases Prusiner , can proSc) of the cellular form of the prion protein (PrPC). In the mature form, PrPC is a ~ 210-amino-acid-long, monomeric, glycosylphosphatidylinositol (GPI)-anchored membrane glycoprotein with high primary and tertiary structure identities across mammals. While PrPC N-terminus is unstructured, PrPC C-terminus is folded into a globular domain composed of three α-helices and a small two-stranded β-sheet .Prions are formed from abnormally folded conformers . In acquired cases, the initial PrPSc conformer would be acquired accidentally.As for conventional pathogens, PrPSc levels or infectivity) during neuroinvasion have served to elaborate prion replication models. In essence, these models state that monomeric PrPC is constantly recruited by PrPSc assemblies, allowing a cooperative production and accumulation of further PrPSc assemblies. The most popular models remain so far the autocatalytic conversion model by Griffith , this corresponds to the coexistence of strains. One may be dominant and impose its phenotype but subdominant strains may co-propagate. At the strain level, this corresponds to different PrPSc subpopulations varying not only in their quaternary structures, but also at lower levels of structuration (tertiary and secondary), and impacting in turn their replicative and biochemical properties.PrPSc assemblies. Biochemically, these PrPSc species can differ in their posttranslational modifications , their relative resistance to protease digestion or relative stability towards chaotropic treatment  or heat treatment , prion strains exhibit specific and synchronous incubation times, stereotyped clinical signs, and neuropathology, including the deposition of PrPSc and of vacuolar lesions in specified regions of the CNS, and specific tropism for peripheral tissues including the lymphoid tissue  in the PrPSc state. Where the SSD are located in PrPSc assemblies and how the SSD specify different biological phenotypes remain poorly understood.Based on biochemical and neuropathological analyses in affected individuals and/or on strain typing studies in laboratory animals, at least eight different strains have been isolated from scrapie-infected sheep and goats , three strains from bovines with BSE  and two atypical, putatively sporadic strains), five strains from North American cervids infected with CWD, three strains from Scandinavian CWD, and ten strains from humans with prion diseases Fig. a. This pC showed that a large proportion of the circulating isolates in Europe were composed of two co-propagating strains, which were termed LA19K and LA21K . To provide insights on the molecular determinants of strain predominance, sheep scrapie isolates containing variable proportions of LA21K and LA19K prions were transmitted experimentally to transgenic mice expressing ovine PrPC at different levels in the brain. Remarkably, LA21K replicated dominantly in transgenic mice expressing near-physiological PrPC levels, whereas LA19K phenotypically outcompeted LA21K in transgenic mice expressing high PrPC levels  can co-propagate, at different rate. Many examples can be found in animal and human prion diseases. Transmission of classical scrapie field isolates from sheep and goats to transgenic mice expressing ovine PrP21K Fig. ). LA21K C levels, the spleen expressing ~ 20-fold reduced levels of the normal protein compared to the brain . Such dIn another example of co-propagating strains within a single host, the second co-propagating strain was barely detectable. Sheep infected with atypical scrapie . TransmSc signatures termed type 1 and type 2 by immunoblot has been observed in many patients with sporadic CJD  co-propagated in variable amounts .To conclude, strain co-propagation in single infected host may be the rule rather than the exception. As co-propagation identification mostly relies on experimental transmission with more astringent replicative conditions for one of the strains, it cannot be excluded that strain co-propagation results from a unique progenitor strain that spontaneously evolves in these new conditions (see below) or because of intrinsic instability  digestion. By developing a conformation-dependent immunoassay, which detects specifically PrPSc immunoreactivity versus PrPC following chaotropic agent resolved denaturation, Safar and colleagues revealed the existence of protease-sensitive PrPSc alongside the canonical PK-resistant PrPSc conformer (termed PrPres). Protease-sensitive PrPSc was detected in eight different prion strains, including biologically cloned strains  of PrPSc is anchorless in wild-type animals , size exclusion chromatography, and asymmetric fast-flow-field fractionation have been extensively used to explore the quaternary structure of PrPSc assemblies with a size equal or below a PrP pentamer exhibited the highest specific infectivity values. These values were 1000 to 10,000-fold higher than those from the bulk of PrPSc assemblies with an estimated size of ~ 30-mers  of size-fractionated assemblies were compared, the variations in the prion titer of the assemblies were decorrelated from size variations . For exers Fig. ). CollecSc assemblies. This pleiomorphism can be seen at different scales, in infected host populations, in infected hosts and within a single strain. Whether the intra-strain diversity is in fine similar to the inter-strain diversity remains to be seen. In the future, phenotyping tools with more discriminative power than bioassays may help resolving this question and identifying in PrPSc assemblies the domains responsible for intra- and inter-strain variability.To conclude this section, there is compelling evidence that prions are formed from a spectrum of heterogeneous PrPSc heteroassemblies, raises the question of such structural diversification. As a precise molecular mechanism of prion replication is lacking, only hypotheses can be formulated. The prion replication dogma, which remains mostly theoretical, can be split into three steps  is only due to the higher stability of PrPSc assemblies compared to the stability of the PrPC fold. The amyloid end-elongation by monomer addition remains until now the most widely accepted mechanism of templating  or change in PrPC backbone and/or post-translational modifications. Yet, such external perturbations have to accommodate the reaction mechanism at work in the end-elongation templating. The induced fit adjustment of PrPC on PrPSc can be decomposed in three elementary steps, each one being governed by an equilibrium between backward and forward steps  unfolding of PrPC into PrPU*. Indeed, among all amyloidogenic proteins, PrPC stands apart amid its folded native state  prior to the acquisition of any new fold. The importance of this step is experimentally well illustrated in the cell-free formation of synthetic prions where a partial unfolding of recombinant PrP is required to induce PrP fibrils formation  at different time points of the disease showed that the early steps of prion replication generated small oligomeric PrPSc objects . Ai size was below a PrP pentamer. The second step, which required the presence of PrPC, transformed the Ai oligomers into larger ones (termed Bj)  the irreversibility of the transformation of Ai into Bj , and (3) the structural differences in the elementary bricks  Fig. b. This wte), and  the struC itself, under the influence of environmental fluctuations where replication occurs.To conclude this section, there are at least two possible main ways for prion structural diversification, one due to the replication process itself and the other one due to PrPC from a foreign species but unable to adapt on further passage, a process referred to as nonadaptive prion amplification  with little or no species barrier  are highly resistant to classical scrapie prions  quasispecies concept, Collinge and Clarke (Sc components or substrains and (ii) host PrPC can accommodate a certain portfolio of PrPSc conformations in the pathological state. On cross-species transmission, if one (major or minor) subcomponent lies within the portfolio of conformations host PrPC can accommodate in the PrPSc state, there will be preferential selection of this compatible conformation and crossing of the species barrier. It is thus expected that the time to disease onset and the attack rate in the new host will mostly reflect the initial concentration of this optimized subcomponent. Above a certain concentration threshold, the attack rate should be relatively high.Before PrPd Clarke  adapted d Clarke  to explad Clarke b. In essSc assemblies molecular diversity, this model would readily accommodate prion strains co-propagation in a single host, one being preferentially selected on cross-species transmission amid a compatible conformation. It might potentially accommodate PrPSc assemblies heterogeneity at the intra-strain level, as long as one consider that these assemblies can become bona fide strains in the new host. The conformational selection model does not address the molecular mechanism for mutant emergence as such mutant cannot pre-exist in the quasispecies of molecular substrains per se . The model states in essence that mutation can occur because of the intrinsic instability of certain strains   Fig. d. This mSc assemblies that finally adapted on serial passage in the new PrP transgenic host did not differ in terms of strain properties from unfractionated prions, meaning that if an optimized conformation pre-existed, it was not lost during fractionation. A second counterargument necessitates to detail one of the experimental paradigms used: The rapidly pathogenic LA21K fast scrapie prion strain . This iSc assemblies diversity at the level of the host or the strain must be taken into account when addressing at the molecular level the issue of prion evolution during cross-species transmission. The conformation selection models and the complementation models consider PrPSc diversity with respect to prion substructure or substrains. The second model would go a step further by taking account the dynamics of the assemblies.To conclude this section, PrPSc assemblies diversity, dynamic of formation, and exchange provide new mechanistic insights into prion replication and adaptation. This provides prions with an evolutionary advantage due to selection of best replicator or mutational events in different environments to finally ensure persistence and diffusion within the host or at the population level.This review tentatively unravels the many shades of prion assemblies diversification and the need to bypass the “one assembly fits all” approach to understand prion replication and adaptation at the molecular level. PrPSc assemblies are organized in a specific manner within a fibrillar supra-organization which is extremely stable. It remains so far difficult to conciliate or to find commonalities between the “deadpan” aspect of these emerging structures and PrPSc diversity and dynamicity. The next challenge will be to provide structures at high-resolution of the assemblies that preserve their diversity.High-resolution structures of prions purified to homogeneity are beginning to emerge. In essence, they suggest that PrP


Centrocercus urophasianus; hereafter sage-grouse) are a species of conservation concern that rely on large tracts of structurally and functionally diverse sagebrush (Artemisia spp.) communities. Using a 12-year (2008–2019) telemetry dataset, we documented immediate impacts of wildfire on demographic rates of a population of sage-grouse that were exposed to two large wildfire events  near the border of California and Nevada. Spatiotemporal heterogeneity in demographic rates were accounted for using a Before-After Control-Impact Paired Series (BACIPS) study design. Results revealed a 40% reduction in adult survival and a 79% reduction in nest survival within areas impacted by wildfires. Our results indicate that wildfire has strong and immediate impacts to two key life stages of a sagebrush indicator species and underscores the importance of fire suppression and immediate restoration following wildfire events.Wildfire events are becoming more frequent and severe on a global scale. Rising temperatures, prolonged drought, and the presence of pyrophytic invasive grasses are contributing to the degradation of native vegetation communities. Within the Great Basin region of the western U.S., increasing wildfire frequency is transforming the ecosystem toward a higher degree of homogeneity, one dominated by invasive annual grasses and declining landscape productivity. Greater sage-grouse ( While wildfire is essential in shaping and maintaining many ecosystem processes2, increases in the duration, frequency, and size of wildfires3 threatens to transform many ecological systems. Faunal specialists are particularly vulnerable to rapid landscape level changes because they often exhibit relatively inflexible sets of behaviors that prevent them from adapting at a pace that matches their altered environment4. Populations of greater sage-grouse  located in the Great Basin of the western U.S. are consistent with this phenomenon, and are expected to continue to decline5 under future climate scenarios7. Moreover, the species’ status as an ecological indicator9 suggests that declines are of greater significance and a symptom of systemic-scale degradation.Climatic changes, like rising temperatures and drought, are driving more frequent and severe wildfire events on a global scaleArtemisia spp.) ecosystems because they rely on large, undisturbed, and heterogeneous sagebrush communities to complete a sequence of distinct life stages12. Reproductive displays often occur on communal breeding grounds (leks) and individuals often return to the same leks over multiple breeding seasons17. Within a historical context, this behavior likely resulted in higher fitness by increasing an individual’s knowledge of a relatively stable environment18. However, site fidelity could become a maladaptive behavior following wildfire-induced habitat alterations. For example, the continued use of wildfire-affected landscapes by female sage-grouse for nesting, despite reduced shrub cover and a high abundance of non-native annual grasses, can result in reduced adult19 and nest survival21. When avoidance of fire affected areas does occur, it may be delayed by several years22, which could lead to short- and long-term demographic consequences. The life history requirements of sage-grouse combined with the rigidity of their philopatric behavior (tendency to remain or return to the same areas) offers an opportunity to study contemporary ecological impacts of wildfire on sagebrush-dependent wildlife within the Great Basin.Sage-grouse are an ideal candidate for evaluating wildfire impacts to sagebrush , red brome (B. rubens), medusahead wildrye (Taeniatherum caput-medusae), and ventenata (Ventenata dubia). These invasive grasses are reshaping the fire regime through a positive feedback loop32 that increases fine fuel continuity, reduces spatial complexity, and increases fuel load35. Furthermore, the ability of invasive grasses to rapidly reestablish in a post-fire landscape, means that they often outcompete native plant species that have evolved under more moderate fire regimes37. As a result, the system is advancing toward a higher degree of homogeneity, and landscape productivity is in a state of decline38. Managers responsible for administering conservation measures like fire suppression, prevention, and restoration could help reverse trends, and may find success in directing finite resources to areas or populations that express the greatest need. Specific to sage-grouse, it is critical to understand which vital rates are most adversely affected by wildfire. Unfortunately, the literature on sage-grouse response to wildfire is relatively sparse to date and the studies that do exist often lack a spatial or temporal control40. Thus, information on the existence and quality of pre-fire systemic heterogeneity is missing and the absolute effect of wildfire on sage-grouse populations is unknown. To help fill that information gap, we utilized a long-term monitoring dataset41 that captured the response of sage-grouse following two wildfire events  that occurred within the Virginia Mountains study area between 2008 and 201942. We chose to evaluate changes in nest and adult survival using a robust Before-After Control-Impact Paired Series (BACIPS) design43 because those vital rates are crucial to population maintenance and growth46.Historically, wildfire activity has helped shape and maintain the vegetation component of the Great Basin, producing heterogeneous landscapes through disturbance and ecological successionPinus monophylla, Juniperus osteosperma) woodland (mid-elevation), and mountain shrub (high-elevation). Between 2008 and 2019 the study area experienced two independent wildfires over two consecutive years (2016–2017)42. The VMFC started on 28 July 2016 and consisted of five geographically isolated, but proximal fires, all of which originated from lightning strikes during a single storm system. The total area burned during the VMFC was 27,171 ha with 22,282 ha occurring within the study area boundary . The LVF started on 11 July 2017 and consisted of a single, contiguous burn, which originated along Highway 395 approximately 40 km northwest of Reno, Nevada. The LVF burned a total of 33,886 ha with 32,585 ha occurring within the study area boundary . The total area burned across both wildfire events was 50,412 ha or 40.8% of the study area , USA and northeastern California (Lassen County), USA and occupies the Basin and Range Province, which is a physiographic region characterized by an alternating pattern of generally north–south oriented valleys and mountain ranges  radio-transmitter equipped with mortality sensor. VHF collars did not exceed 3.5% of bird body mass . Capture, handling, and marking procedures were approved by U.S. Geological Survey Western Ecological Research Center's Animal Care and Use Committees (WERC-2015-02). Reporting of animals used in analyses follows recommendations from the ARRIVE guidelines49.We captured female sage-grouse between 2008–2019 during the spring (March–April) and fall (September–November) seasons at night using a spotlighting technique52, which necessitates location data of higher temporal resolution where the objective is assessing variation in survival as a function of spatial covariates. Conversely, late fall to early spring is marked by a higher degree of sociality55, which allows a relaxation of relocation rates and a borrowing of information across individuals using time-varying, population-level parameters to impute missing values .Radio-marked sage-grouse were monitored according to season  and individual reproductive status . We located individuals once every three days during the nesting season (March–June) to capture nest initiation. Females located within the same area on two consecutive visits were visually inspected to confirm nesting activity. Once confirmed, we continued monitoring nests every three days until fate was determined . Nests were considered successful if ≥ 1 egg hatched, which was determined by examination of eggshells or the presence of chicks within or near the nest bowl. We categorized nests as unsuccessful if no eggs were present, all eggs showed signs of depredation , or intact eggs failed to hatch and the female did not return (i.e. abandoned). We continued to monitor female sage-grouse once a week following nest failure to confirm possible re-nesting attempts. Individuals that successfully hatched ≥ 1 egg were monitored up to 50-d post-hatch at 10-d intervals. Monitoring of females with broods ceased once fate was determined . Individuals that were no longer nesting or rearing broods were monitored once per week until the fall season (early September) at which point locations were acquired at 1–2-mo intervals using fixed-wing aircraft . Aerial telemetry was conducted during spring and summer months (March–August) to aid ground crews when workload or access curtailed timely relocation of radio-marked birds. Accuracy of aerial telemetry was assessed using stationary collars of known location, and never exceeded 200 m. Telemetry effort was normally distributed across the year with the bulk of locations occurring between April–July. This period is associated with a higher degree of individual-based decision making and a more diffuse population-level space use behavior43 within a Bayesian framework using nest monitoring and telemetry data collected before and after wildfire events within impact and control areas respectively 41. The purpose of the BACIPS analysis was to quantify differences in nest and adult survival across the four BACIPS groups to yield a relative effect of wildfire on nest and adult survival. We used wildfire data downloaded from the Monitoring Trends in Burn Severity (MTBS) website42 to generate the four BACIPS groups which served as a categorical covariate depicting the spatiotemporal relationship of each bird relative to the VMFC and LVF. Values were restricted to the range of positive integers 1–4 and represented, in order, the four BACIPS groups associated with wildfire . Categorical periods (before vs. after) represent the position of a location in time relative to a wildfire event, whereas categorical treatments (impact [inside] vs. control [outside]) represent the position of a location in space relative to a wildfire perimeter.For both nest and adult survival we employed a BACIPS design42.We conducted a BACIPS study design within a Bayesian framework to estimate the effects of the VMFC and LVF using nest monitoring data collected at the Virginia Mountains study area from 2008 to 2019. We generated encounter histories for each sage-grouse nest  using the date the nest was found, last date observed active, and date that nest fate (i.e. successful or unsuccessful) was determined. Nests that failed between the initial nest location (i.e. first found) and the second nest check were assumed to survive one day, which allowed us to retain these instances and avoid inflating survival estimates. For nests, the BACIPS consisted of concurrently monitoring nests before and after the wildfire event within (impact) and outside (control) of the wildfire perimeters. Nests were assigned to each respective treatment group (control or impact) by overlaying nest locations with the VMFC and LVF perimeters57 to estimate a daily unit hazard (UH) for each nest. We specified separate baseline log-hazards (UH) through the expression:We used Bayesian shared frailty modelsi and d, reference nest and day, respectively.Subscripts i) took the form:CH) function. The discrete outcome . We present median values of estimated parameters and 95% credible intervals unless otherwise specified.Posterior distributions of parameters were estimated using Markov chain Monte Carlo (hereafter MCMC) simulations from three chains of 10,000 iterations thinned by a factor of 10 following a burn-in of 50,000 iterations. Models were run in program JAGS version 4.343 and CI-divergence measures61 applied to the posterior distributions generated from our frailty model. Using a Bayesian approach to calculate BACIPS ratios provides test statistics that compute positive or negative effects43. To evaluate wildfire treatment (i.e. impact or control) effects for this BACIPS study, we used the posterior distributions of nest survival probabilities (i|c) for each period (p), where p references periods before (b) and after (a) the wildfire:We evaluated evidence of effects of wildfire using published BACIPS ratio methodsWe then estimated the posterior distribution of the mean treatment effect for nest survival:61. CI-contribution and CI-divergence were calculated as follows:We also calculated two control-impact (CI) measures. CI-contribution quantifies by what extent the change between periods is stronger (i.e. greater change within impacted sites or control sites). CI-divergence quantifies the degree to which control and impact sites have diverged between the after and before periodFor CI-contribution, positive values demonstrate a greater change in impacted areas relative to control areas, whereas negative values reflect greater changes in control areas. For CI-divergence, positive values reflect greater variability between impact and control areas following wildfire, while negative values reflect decreased variability following wildfire. By using these CI measures combined with BACIPS ratios we were able to conduct a comprehensive investigation of wildfire impacts on nest survival.42. Individuals that were relocated ≥ 2 times within the same month had the opportunity to occupy more than one BACIPS group. A simple decision tree was constructed to handle these events and was predicated upon a hierarchy of assumed impact to survival wherein the after group took precedence over the before group, the impact group took precedence over the control group, and the treatment group took precedence over the period group. Because a relatively small proportion of the dataset required the application of the decision tree (~ 9.3%), an alteration in the hierarchy is suspected to have had minimal impact to results.Unlike nests, adults can change BACIPS group assignment based on their location in space and time Fig. . This qu62. The time-varying covariate for age class allowed yearling sage-grouse to graduate into the adult age class on 1-March of each year and remain there for the duration of the study. Sage-grouse captured as adults remained in the adult age class for the duration of the study. The use of a time-varying covariate for month allowed us to account for temporal variability in survival across a year62. This technique was necessary to account for potential sources of bias because of uneven sampling (i.e. captures) among spring and fall seasons across years, and the variability in survival across seasons.Within the adult survival analysis, additional time-varying covariates were specified for age class and month based on a priori knowledge of potential confounding effects that could arise from variation in survival associated with sage-grouse life histories57, similar to that shown in Eqs.  and 34 post-wildfire nests . Nest survival probabilities within control sites were 0.16 (95% CRI = 0.04–0.38) before wildfire and 0.19 (95% CRI = 0.03–0.46) after wildfire Table , meaningWe estimated yearling and adult survival probabilities in relation to wildfire affected areas using 178 radio-marked, female sage-grouse. Due to the relatively long-lived and mobile nature of sage-grouse, it is difficult to summarize the number of individuals belonging to each BACI group. However, the percent of relocations recorded within each of the four BACI groups was 32.2% (before-control), 34.7% (before-impact), 23.1% (after-control), and 9.9% (after-impact). Survival probabilities were higher among individuals occupying control sites during the entire duration of the study. However, greater disparity among control and impact areas was observed, post-fire. During pre-fire periods control sites exhibited survival probabilities around 0.79  compared to those that did not , suggesting the areas may have previously experienced habitat degradation. A previous wildfire occurred within this study area during 1999 (i.e. Fish Springs fire), and largely overlapped fire perimeters from the VMFC and LVF. Thus, the low pre-fire estimates of adult survival observed in this study may indicate the existence of chronic impacts of wildfire. Furthermore, our pre-wildfire estimates of nest survival align with post-wildfire estimates observed from another study of sage-grouse nest survival within the Great Basin71. Thus, the vital rates observed in this paper likely reflect a combination of both immediate and long-term impacts of wildfire and highlight the amplification of effects that shortened fire cycles can have on sage-grouse populations.Conversion of shrublands to annual grasslands not only results in more persistent impacts of wildfire on sage-grouse, but also changes to fire regimes, namely more frequent and severe wildfires39. Sagebrush, an important forage and cover shrub, is slow to reestablish and is often killed during low intensity fires72. With over 40% of our study area burned from the VMFC and LVF, important forage and refuge sources were likely impacted. Reduction of vegetation from wildfire may increase detection, leading to not only higher predation rates on adults, but also higher likelihood of nest predation because visual predators like common ravens (Corvus corax) can more readily detect female sage-grouse attempting to return to their nest. Recent studies have found sage-grouse that nest within burned areas experience lower nest survival compared to those in unburned areas because of decreased cover73. Furthermore, a recent study examining post-wildfire effects on adult survival found high mortality for individuals that stayed or returned to the burned area likely because of loss of habitat needed for refuge from predation40. Because we did not observe direct fire mortality of adult birds in this study  it is inferred that the majority of fitness consequences stem from post-fire utilization. During winter months, sagebrush becomes increasingly important to sage-grouse populations as it represents the primary component in their diet55. This period is also marked by elevated survival and increases in endogenous reserves. The loss of sagebrush from late season fires combined with large snow years could lead to decreased food availability, which can have immediate impacts on over-winter survival75 and carry-over effects on body condition leading into the breeding season. Despite the fitness consequences associated with the use of burned areas, we found that sage-grouse are apt to reoccupy areas shortly after wildfire, which is consistent with several other studies73. The high level of philopatric behavior exhibited by sage-grouse14 makes them ill-suited to adapt at the same rate that modern-era landscape alterations are occurring, especially as wildfire frequency and severity increase across the American West.Many studies have addressed the impact of wildfire on sage-grouse habitat finding that wildfire reduces cover needed for nesting and other life stages, increasing the chance of mortality and nest failureThis study was not without limitations. First, while traditional BACIPS assumes the entire population is either impacted or not (control), we lacked independence between individuals for each treatment group. However, it is important to point out that our design accounted for movement of sage-grouse in and out of impact areas thereby allowing a more powerful approach than traditional BACIPS design. Additionally, our study design limited our ability to research the conditions driving the mechanisms behind the BACIPS results such as changes in sage-grouse habitat. While beyond the scope of this study, additional investigation specifically focused on the underlying mechanisms leading to low survival is warranted. Our study suggests that management decisions may be better guided with further understanding of how wildfire affects the indirect factors which influence sage-grouse predation risk, food availability, and habitat cover.5. Our study has provided clear, compelling evidence that wildfire adversely impacts the survival and reproductive potential of this sagebrush-obligate and indicator species. Furthermore, results have demonstrated that wildfire has the potential to reduce population growth and maintenance via both short- and long-term mechanisms. For populations that exist on the periphery of the sage-grouse range, like the one studied here, wildfire has the potential to increase extirpation probabilities67. As wildfire trends continue, ecologically valuable habitats are likely to become increasingly fragmented and/or degraded72, further reducing the ability of populations to self-rescue. Management practices such as wildfire suppression may be of greater importance within drier and warmer low- to mid-elevation sagebrush communities as these areas have slow-to-no recovery potential and are at a higher risk of invasion by pyrophytic annual grasses76. Restoration activities  aimed at replenishing immediate resource needs may represent an alternative option where wildfire suppression is logistically more difficult or less effective when it does occur77. By identifying sage-grouse life-stages most affected by wildfire, wildlife managers may better identify management practices which best support sage-grouse populations78 and curtail the effects of increasing wildfire within the Great Basin.Understanding how wildlife populations respond to landscape disturbances is central to management and conservation decisions. Within the Great Basin, those decisions are being framed around wildfire, which is expected to reduce sage-grouse populations by approximately 43% by 2044