Physical activity is a commonly prescribed medicine for people with conditions such as obesity and diabetes who are also at increased risk of being hospitalized or severely ill from COVID-19. However, many people are reporting challenges in engaging in a healthy dose of physical activity amid the pandemic.This rapid review synthesizes the current empirical evidence about the impacts of COVID-19 on people’s outdoor physical activity and sedentary behavior while highlighting the role of community environments in promoting or hindering physical activity during the pandemic.Literature searches were conducted using keywords related to COVID-19: physical activity, mobility, and lifestyle behaviors. Eligibility criteria were peer-reviewed empirical and quantitative studies published in English, addressing COVID-19 and using physical activity and/or sedentary behavior as the study outcomes.Out of 61 eligible studies, the majority (78.3%) were conducted in Asian and European countries, with only four (6.7%) being US studies. The results showed that COVID-19 was linked with significant decreases in mobility, walking, and physical activity, and increases in sedentary activity. A few studies also reported contradicting results including increased uses of parks/trails and increased recreational activity among certain groups of population.Evidence suggests an overall negative impact of COVID-19 on physical activity, with differential effects across different sub-populations. Significant knowledge gaps are also found in the roles of social and physical attributes that can promote physical activity during pandemics with reduced safety risks. The spread of coronavirus disease 2019 (COVID-19), classified as a pandemic by the World Health Organization on March 11, 2020, has greatly impacted people’s daily lives globally [Outdoor physical activity holds strong potential as an effective coping and preventive strategy given its many well-documented physical, social, and mental health benefits for people of all ages, especially those with or at risk of developing chronic diseases ,4. Many While considering health-promotion strategies and interventions, Stokols (1992) emphasized the nature of individuals’ interactions with physical and sociocultural environments from an ecological perspective, focusing on the need of addressing environmental factors to change/promote health-related behaviors . EcologiCOVID-19 has brought a new layer of challenges to our health and healthy behaviors. People worldwide are reporting challenges in engaging in a healthy dose of physical activity amid the pandemic, with up to a 50% decrease of physical activity in some areas. This decline is in part due to the limited and inequitable availability of safe outdoor community resources  that support physical activity . DespiteThis rapid review aims to show whether COVID-19 has impacted people’s outdoor physical activity and sedentary behavior during the early phases of the pandemic, by synthesizing the current empirical evidence on this topic, and highlighting the roles of community environments in promoting or hindering physical activity during the pandemic. Going beyond the scope of previous literature reviews on COVID-19, this study includes multiple and specific physical activity outcomes , and summarizes several environmental factors shown to be important for promoting physical activity amid the pandemic. By providing a comprehensive and critical examination of the current body of literature on this topic, we aim to provide empirical guidance for policymakers, researchers, and practitioners. This guidance can support those in various professions toward investigating the full range of environmental facilitators and barriers to promoting active living, as an effective way to cope with emotional or mental distress during pandemics like COVID-19.We selected studies that met the following four criteria: 1) addressing the impact of COVID-19, 2) including physical activity  and/or sedentary behavior  as study outcomes, 3) peer-reviewed empirical and quantitative studies including both cross-sectional and longitudinal studies, and 4) studies written in English. We excluded studies on health care facilities and professional athletes, given their unique and narrow focuses that are different from our main study aim targeting general populations in their everyday residential communities.Literature searches were conducted in PubMed on October 23, 2020, using pre-developed keywords related to COVID-19, physical activity, mobility, and lifestyle behaviors. COVID-19 related search terms included “coronavirus” or “COVID-19” or “coronavirus disease 2019” or “SARS-COV-2” or “Severe Acute Respiratory Syndrome Coronavirus 2”. Physical activity related search terms encompassed “physical activity” or “walk” or “bike” or “sedentary” or “exercise” or “active living” or “transport” or “mobility” (www.covidence.org), which is a web-based systematic review software for screening and data extraction. First, studies searched in PubMed were screened based on the titles and abstracts. Second, articles selected from the title and abstract screening went through the full-text sorting. Two researchers completed the screening process independently, and all disagreements were resolved through consensus discussions with a third researcher.Eligible studies were selected in two phases using Covidence  and cycling recreational activity increased by 291% in Oslo, Norway during the COVID-19 lockdown . The othThe overall physical activity levels dropped significantly worldwide during COVID-19, including decreases in light , moderatStudies on mobility showed significant decreases in total time spent in transport ,64, distPhysical inactivity and sedentary behavior became more prevalent during the COVID-19 pandemic. The reviewed studies showed significant increases in time spent sitting ,29,45,46Only one study investigated the influence of the COVID-19 pandemic on total energy expenditure. It revealed a significant decrease in energy expenditure among physiotherapy professionals and students during the COVID-19 lockdown .In general, physical activity and trips for all purposes  decreased remarkably since the start of the pandemic. Despite the recognition that supportive community environments are important for promoting active lifestyles, only a small number  of the included studies investigated the roles of community environments . One study investigated the relationship between different regional settings  and the changes in older adults’ physical activity during the pandemic, which reported a significantly greater decrease in physical activity among those living in urban areas . AnotherOf the three studies considering dwelling types (detached house vs apartment or flat), two Canadian studies focusing on children and youth populations showed a notable increase in outdoor activities  and overall time spent outdoors among those living in detached houses, compared to residents of apartments ,57. The Five articles focusing on the association of nature and green spaces with the changes in physical activity during the COVID-19 pandemic showed inconsistent results ,51,55,79In terms of neighborhood infrastructure, three articles considered neighborhood environmental conditions  to examine their relationships with the changes in physical activity ,42,51. AThis rapid review suggested that COVID-19 greatly impacted people’s daily mobility and physical activity patterns. Overall, people worldwide showed decreases in daily physical activities and increases in sedentary time  and time spent at home, compared to the pre-COVID times. As increasing evidence confirms that sedentary behavior, independent of the physical activity levels, accompanies multiple health risks including chronic diseases, obesity, depression, and anxiety -83, furtGiven the time-sensitive nature of published studies on this topic, about a quarter of all the reviewed studies (15 out of 61) relied on descriptive statistics to examine changes in walking, physical activity, sedentary behavior, and mobility behavior, without any statistical tests. Nine out of the 61 (15%) articles included were longitudinal studies comparing the data collected from two different periods before and during COVID-19. Most of the reviewed studies used self-reported or parent-reported survey data asking whether participants’ physical activity had decreased, increased, or remained constant. Seventeen out of the 61 (30%) included studies had limited sample sizes of fewer than 400, ranging from 24 to 315. Even for the articles with larger samples (n ≥400), only 20 studies were representative of the population by using random sampling methods. Lastly, this review identified a limited number of studies (11 out of 61) targeting vulnerable populations such as older adults and children.While we emphasize the importance of future research on vulnerable populations, the review identified the lack of studies on highlighting the roles of community environments in physical activity and health-related outcomes across different populations in terms of age, gender, income, and health conditions amid COVID-19. For this review, about half  of the eleven environment-related articles focused on specific populations including children (n = 3), older adults (n = 2), and heart failure patients (n = 1). This may highlight the benefits of the community environment for those specific populations who may have limited access to out-of-neighborhood destinations/opportunities. In addition, many existing studies emphasized the importance of neighborhood-level built environments where residents’ daily activities occur  on health-related outcomes; and the environmental impacts on those outcomes tend to differ across different populations -87. For This review identified four environmental factors, including regional locations, dwelling types and density, nature and green spaces, and neighborhood infrastructure related to changes in physical activity. In addition to their community strategies supporting physical activity, the Centers for Disease Control and Prevention provided guidelines on how to be physically active during COVID-19 by visiting parks, pools, or recreation facilities. Although the number of empirical studies on COVID-19 that consider the roles of built environments is small, many leading organizations/initiatives, such as the American Association of Retired Persons (AARP), National Association of City Transportation Officials (NACTO), and professional design groups  have published design guidelines with implementable environmental strategies  to cope with the “new normal” following the coronavirus pandemic. These publications address the design conflicts, dilemmas faced, and the potential solutions  to provide better outdoor spaces for everyone to stay healthy and engaged, while ensuring safety from infection. For example, NACTO released a resource  that includes detailed strategies to redesign and adapt streets for new uses amid COVID-19. AARP published design briefs responding to the impact of COVID-19 on commercial areas, informing local leaders to make their communities more livable and protect their residents from COVID-19 . Their dBased on the knowledge gaps mentioned above, longitudinal studies utilizing more vigorous sampling strategies and objective measures of physical activity can help increase the study generalizability and reduce the survey recall bias. More work is needed to investigate the long-term effects of COVID-19 on physical activity and health-related outcomes to further explore how people are recovering from COVID-19. Moreover, further research is needed to investigate the impact of COVID-19 on vulnerable populations  and identify potential social and environmental strategies for promoting active living of everyone after COVID-19.Given the significance of community environments in maintaining and promoting health behaviors and health outcomes, and ith the limited empirical evidence on the roles of community environments amid COVID-19, more studies are needed to explore how they can help people cope with COVID-19 and how the design dilemma can be addressed in the future. Stronger collaborations between public health and urban planning/design sectors are needed to identify locally implementable environmental strategies that can help respond to the multiple public health challenges that this global pandemic has brought. Drawing from the findings of this review, environmental strategies needing further collaborative efforts include the following.Consider potential negative impacts of urbanization and compact developments on physical activity  and health (rapid spread of infections) during pandemics like COVID-19.Highlight the importance of providing free and accessible outdoor spaces for all populations (equity).Consider shared backyards for residents of high-density dwelling types such as apartments and public/affordable housing, where provision of private outdoor spaces is difficult.Consider transforming community vacant land into small parks/green spaces in areas lacking safe outdoor resources to support physical activity and help people cope with mental health problems.Consider the importance of safe neighborhood streets and sidewalks to serve as health infrastructure supporting healthy physical activity, especially when other physical activity resources may be unsafe or closed during pandemics like COVID-19.In addition, many of the pandemic-responsive design/planning strategies proposed and implemented by various organizations and communities have not been examined for their effectiveness. Future research that documents and quantifies the specific benefits and costs of the various pandemic-responsive strategies is needed to develop evidence-based intervention strategies to enable our cities to be better prepared for future pandemics and other public health challenges. In addition to those environmental strategies, educational or promotional programs/events or the use of walking/cycling applications can be encouraged to promote engagement in physical activity.This rapid review has two major limitations. First, we only used one database for the comprehensive database searches to ensure a timely review. However, Google Scholar searches were also conducted as a supplemental approach to help reduce the possibility of omitting important studies. Second, this review was limited to peer-reviewed quantitative studies in English, which may result in missing relevant qualitative studies and those written in other languages and/or not peer-reviewed. We, however, provided a brief discussion on the grey literature highlighting a few published guidelines most relevant to this review.Evidence suggests an overall negative impact of COVID-19 on physical activity, with differential effects across different sub-populations. Significant knowledge gaps are also found in the roles of community environments that can promote healthy outdoor activities during the pandemic with reduced safety risks. A major paradigm shift is expected in planning and design to address the dilemma of creating compact and sustainable built environments while providing sufficient protection from infectious diseases and flexibility to accommodate the dynamic needs of outdoor activities during and beyond the pandemic.


Hand hygiene has always been an area of emphasis within the hospital setting, never more so than during the coronavirus disease 2019 (COVID-19) pandemic. The consumption of alcohol-containing hand sanitizer products, whether intentional or accidental, often garners attention, particularly since these products may contain methanol. This report describes a case of surreptitious theft and intentional ingestion of the emergency department’s (ED) ethanol-based hand sanitizer by a patient who presented to the ED clinically intoxicated with a high ethanol level. When the patient remained clinically intoxicated for more than 18 hours and had a rising serum ethanol level in the ED, clinicians searched his belongings and found several purloined bottles of the ED’s hand sanitizer. When confronted, the patient admitted to ingesting hand sanitizer during his ED stay. This case highlights the need for clinicians to be suspicious of intentional ingestion of ethanol-containing products for at-risk patients. Additionally, it demonstrates that measures and protocols should be put in place that minimize the ability for the inappropriate use of these widely accessible products within the hospital. Non-beverage or surrogate alcohols are substances that may be consumed as an alternative to traditional alcoholic beverages containing alcohol. These substances may include mouthwash, perfumes, aftershave, cough syrup, liquid cold remedies, rubbing alcohol, gasoline, paint thinner, jellied alcohols, hairspray, and hand sanitizers -4. Some Per World Health Organization and Centers for Disease Control guidelines for hand hygiene, alcohol-based hand sanitizers are readily available in healthcare settings ,6. Used A 30-year-old male with a history of ethanol use disorder (consuming 1.5 L/day of liquor) complicated by withdrawal seizures, depression, and asthma presented to the ED via emergency medical services after being found intoxicated in a park. Initial vital signs were notable for blood pressure 146/79 mmHg, heart rate 118 beats/minute, respiratory rate 20 breaths/minute, temperature 98.6°F, and oxygen saturation of 99% on room air. His physical examination, aside from being intoxicated with slurred speech and an unsteady gait, was unremarkable. There was no external evidence of trauma. Given his risk of self-reported withdrawal seizures and delirium tremens, the patient was placed on a telemetry monitor and on the Clinical Institute Withdrawal Assessment for Alcohol (CIWA) protocol. The patient received 2 liters of normal saline fluid and intravenous lorazepam. His initial blood alcohol level (BAL) was 359 mg/dl. The patient initially requested to be transferred to a local program for alcohol detoxification but the requirement for eligibility was a BAL less than 100 mg/dl. The patient was re-evaluated for sobriety during changes of shift by the oncoming emergency medicine resident. Strangely, however, he remained clinically intoxicated after 18 hours in the ED. He was subsequently found to have several bottles of the hospital’s hand sanitizer in his possession. At this time, a repeat BAL was as 372 mg/dl and the patient was admitted to the hospital 20 hours after his initial arrival to the ED for observation and monitoring for possible development of withdrawal symptoms.Although cases of intentional hand sanitizer ingestion have been previously described, we describe a unique case in which a patient, who voluntarily requested to enter a detoxification program, did not disappear or hide to secretly ingest hand sanitizers -11. InstAlthough ingestion of ethanol-based hand sanitizers should follow the general treatment protocol as ethanol consumption, intoxication from ethanol-based hand sanitizers can lead to serious and life-threatening adverse health effects. These include, but are not limited to, central nervous system and respiratory depression, cardiac dysrhythmias or arrest, nausea and vomiting, liver injury, and lactic and ketoacidosis . ProtectCurrently, there are no recommendations regarding the potential misuse of hand sanitizers. Given the extensive utilization of hand sanitizers, coupled with a surge in ethanol sales since the beginning of the COVID-19 pandemic, healthcare providers should be aware of the potential misuse of hand sanitizers as intoxicants. The widespread endorsement of hand sanitizers by public health and medical experts opens a new dimension in medicine, one in which clinicians must also be cautioned of their potential misuse by patients suffering from alcoholism or other mental illnesses. We recommend that emergency staff be educated regarding the possibility of high-risk patients imbibing hand sanitizer, as well as signs of intoxication or changes in mental status. Clinicians should be well-versed in asking specific questions to patients or family members regarding potential alcohol-containing solutions in the household, such as engine additives stored in the garage or mouthwash in the bathroom.Hospitals should implement measures or protocols that minimize the possibility of the misuse of ethanol-based hand sanitizers. Such protocols include a reevaluation of where hand sanitizer dispensers are physically located throughout the emergency department and their accessibility to patients at higher risk. Since hand sanitizer bottles or pouches in wall dispensers can be easily removed and consumed by patients, we recommend the installation of lockable wall dispensers or the use of alcohol-based wipes. This recommendation would not deter from the practice of using the hand sanitizer when entering or leaving the patient’s room to prevent the transmission of pathogens. Lastly, hand sanitizer dispensers often have the percent alcohol content written on the bottle which may appeal to patients with alcohol dependence and result in consumption. One case report described a patient who secretly drank isopropanol-based hand sanitizer in the bathroom of a hospital because the label indicated “63% v/v isopropyl alcohol,” believing it had higher alcohol content than vodka . Thus, iPromoting and maintaining hand hygiene while also protecting patients with alcohol abuse disorders presents a major challenge to both patient safety and risk mitigation. Clinicians should be aware of the possible misuse of hand sanitizer. Increased awareness and implementation of safety protocols in emergency departments might minimize intentional hand sanitizer ingestion. We recommend the use of lockable wall dispensers as a way to reduce hand sanitizer ingestion in the hospital.Promoting and maintaining hand hygiene while also protecting patients with alcohol abuse disorders presents a major challenge to both patient safety and risk mitigation. Clinicians should be aware of the possible misuse of hand sanitizer. Increased awareness and implementation of safety protocols in emergency departments might minimize intentional hand sanitizer ingestion. The use of lockable wall dispensers or alcohol-based wipes could help to reduce hand sanitizer ingestion in the hospital.


Progress in understanding kidney disease mechanisms and the development of targeted therapeutics have been limited by the lack of functional in vitro models that can closely recapitulate human physiological responses. Organ Chip (or organ-on-a-chip) microfluidic devices provide unique opportunities to overcome some of these challenges given their ability to model the structure and function of tissues and organs in vitro. Previously established organ chip models typically consist of heterogenous cell populations sourced from multiple donors, limiting their applications in patient-specific disease modeling and personalized medicine. In this study, we engineered a personalized glomerulus chip system reconstituted from human induced pluripotent stem (iPS) cell-derived vascular endothelial cells (ECs) and podocytes from a single patient. Our stem cell-derived kidney glomerulus chip successfully mimics the structure and some essential functions of the glomerular filtration barrier. We further modeled glomerular injury in our tissue chips by administering a clinically relevant dose of the chemotherapy drug Adriamycin. The drug disrupts the structural integrity of the endothelium and the podocyte tissue layers, leading to significant albuminuria as observed in patients with glomerulopathies. We anticipate that the personalized glomerulus chip model established in this report could help advance future studies of kidney disease mechanisms and the discovery of personalized therapies. Given the remarkable ability of human iPS cells to differentiate into almost any cell type, this work also provides a blueprint for the establishment of more personalized organ chip and ‘body-on-a-chip’ models in the future. More than 15% of U.S. adults have chronic kidney disease (CKD), and many people are unaware that they have the disease due to the lack of early diagnostic tools or methods ,3,4. ForAs the kidney’s glomerular filtration rate is the most common measure of kidney function, the glomerulus is a critical target for therapeutic development . The glomerulus is the workhorse of the kidney, filtering about 200 L of blood per day. Each glomerulus consists of a cluster of capillaries lined by fenestrated endothelium. A specialized epithelial cell type named podocyte encases these capillaries. Podocytes have foot processes which interdigitate to form a molecular sieve, called the slit diaphragm. Blood gets filtered through the glomerular filtration barrier, which is composed of fenestrated endothelium, glomerular basement membrane (GBM), and the slit diaphragm of the podocytes. Many kidney diseases, including podocytopathies and glomerulopathies, are characterized by podocyte foot process effacement, actin cytoskeletal remodeling, or detachment of podocytes from the GBM . Such ceAlthough animal models are widely used to study human kidney biology and for preclinical drug development, such models often yield results that are not directly applicable to humans due to species-specific differences in biochemical, physiological, developmental, and anatomical characteristics. Furthermore, normal adult or embryonic human tissues are usually unavailable in sufficient amounts for research, and many mouse models ,9,10 do To address these challenges, organ-on-a-chip technologies have been developed to modulate multitissue organization and structure with dynamic control of biochemical cues, vascular perfusion, cellular crosstalk, and mechanical forces to help recapitulate in vivo-like features and functions. For example, cytoskeletal rearrangement and junctional injury in both podocytes and endothelium due to hypertension in a mouse-specific glomerulus chip have been demonstrated . In anotTo date, a human kidney glomerulus chip that consists of genetically matched podocytes and endothelium (thus where both the podocytes and endothelium are derived from the same patient or stem cell line) has not been reported. Such personalized or genetically matched tissue model could advance personalized medicine in the field of nephrology and beyond. By using primary-sourced cells, human kidney glomerulus chips are limited by their difficulty to propagate and/or maintain molecular and genetic characteristics after multiple passages ,22,23. TIn this study, we initially differentiated both vascular endothelial cells and intermediate mesoderm cells (nephron progenitor cells) from the same human iPS cell line. We then incorporated these two cell types in interfacing fluidic channels separated by a porous membrane, where the intermediate mesoderm cells were subsequently induced to differentiate or specialize into podocytes within the urinary compartment of the microfluidic chips, while the endothelial cells were propagated in the vascular channel. Together, these human iPS cells generated a personalized patient-specific glomerulus chip. The structural and cellular maturity of the chip  were confirmed through expression of immunofluorescent markers. The functionality of the chip  was also investigated. Given our ability to reconstitute the kidney’s glomerular filtration barrier, we also employed the engineered system to model drug-induced injury and disease phenotype. The drug-treated glomerulus chip showed a drastic increase in albumin clearance, indicating loss of barrier function. This device is advantageous in modeling salient features of an individual’s glomerular filtration barrier function, disease phenotype, and response to drugs.DU-11 (Duke clone #11) human iPS cell line was obtained from Dr. Nenad Bursac’s lab at Duke University under appropriate material transfer agreements and approved by all involved institutional review boards. DU-11 cells were maintained under feeder free conditions in polystyrene tissue-culture-treated plates  coated with hESC-grade Matrigel . Cells were fed daily with mTeSR1  medium. These cells were passaged every 4–5 days (upon 70–80% confluency) by treatment with StemPro Accutase . DU-11 cells have been tested for and found to be free of mycoplasma contamination . Chromosomal analysis confirmed that these cells were karyotypically normal.g in Advanced DMEM/F12  for 5 min. The cells were seeded on Laminin-511-E8  coated plates with mesoderm induction media as reported earlier.  × UV)/[P]) where [U] is urinary concentration of albumin, UV = volume of media collected from the urinary channel outlet reservoir, and [P] = dosing concentration in the microvascular channel (100 μg/mL). A parametric two-tailed Student’s Previously established kidney glomerulus chip devices employed podocytes and endothelial cells derived from different sources and individuals, and thus these organ-on-a-chip devices contained tissue layers with unmatched genetic backgrounds. Some of the sources of cells for these glomerulus chip devices include animal or non-human sources ,25, primDU-11 human iPS cells produced from a single donor were used to derive human intermediate mesoderm (IM) and vascular endothelial cells (viECs) a. For thThe protocol of Atchison et al. (2020) was used to differentiate the same DU-11 human iPS cell line into viECs in 7 days  Figure a. Briefl−2, 1000 µm × 200 µm (w*h)) compared to the urinary channel ) [For the development of the personalized glomerulus chip, we utilized polydimethylsiloxane (PDMS) microfluidic chips from Emulate, Inc. . The chip includes two parallel fluidic channels positioned on top of each other to recapitulate the body’s dynamic tissue–tissue interface. The top (urinary) and the bottom (capillary) channels are separated by a 50 µm thick flexible PDMS membrane. The membrane consists of hexagonally packed pores with approximately 7 µm diameter which are spaced 40 µm apart from each other. We functionalized the PDMS chip with Laminin-511 as the extracellular matrix protein on both channels to allow two interfacing cell types to anchor onto the porous membrane. Upon cell seeding in the respective channels, the level of shear stress generated by the fluid flow was determined by the flow rate (60 µL/h) and chip dimensions. The capillary channel experienced higher shear stress owing to its smaller dimensions (shear stress = 0.017 dyn cmm (w*h)) . On eachFrom a structural standpoint, the glomerulus is a tuft of capillaries that are encased by terminally differentiated epithelial cells called podocytes, and the lumen is lined by endothelial cells. We seeded our differentiated viECs in the capillary channel to mimic the endothelial circuit of the glomerulus. To form the epithelial layer, we first seeded IM cells in the urinary channel, then differentiated them into podocytes within the glomerulus chip device using podocyte induction medium c. This pBrightfield images of the capillary and urinary channels of the organ chip revealed uniform cell monolayers formed by the iPS cell-derived podocytes and endothelial cells in their respective channels a. The enIn an intact and functional kidney, podocytes develop foot processes that form interdigitations with adjacent podocytes to form the glomerular filtration sieve or network. To examine whether such structure could form in our engineered device, we captured a confocal z-series of our glomerulus chips. As shown by the 3D reconstruction of the confocal microscopy images, human iPS cell-derived epithelium and endothelium formed confluent monolayers on their respective sides of the porous PDMS membrane. Additionally, podocytes in the urinary channel were found to extend their cellular processes through the PDMS membrane pores and towards the direction of the endothelial cells in the capillary channel—a process reminiscent of intercellular crosstalk through physical proximity. Interestingly, we observed that podocin expression was largely localized to the cell bodies of the podocytes, as would be expected for specialized podocytes c. In addp = 0.0169), with the most optimal secretion timepoint occurring on day 23 (p = 0.0001)  f. Taken −1 [−1 of fluorescently labelled albumin to the capillary channel of the chip after ADR perfusion. We observed a significant increase in the urinary clearance of albumin compared to the control (p = 0.0001), successfully recapitulating drug-induced albuminuria (The chemotherapy drug Adriamycin (ADR) has been used as a model of nephrotoxicity in vivo and in vitro ,39. We e−1  was contuminuria f.Traditional tissue culture vessels have been useful in studies of basic biological processes, but these culture systems often fail to accurately model tissue-specific functions or predict in vivo relevance of drug candidates. Animal models have significantly contributed to the field of drug development and toxicity analysis, but researchers have realized the developmental and metabolic discordances between animal and human studies that necessitates establishment of patient-specific platforms to more closely predict human physiologicalresponses. In this study, we engineered a personalized human in vitro model of the glomerulus, a microcapillary-like system lined by epithelial and endothelial cells important for establishing the blood filtration barrier and selective molecular filtration function of the kidney. Development of personalized in vitro models of human tissues and organs could improve the 90% failure rate of clinical trials and minimize ethical concerns surrounding the use of animal models. Emerging organs-on-chips technologies are promising for pharmacokinetics/pharmacodynamic modeling . FurtherThe kidney plays an important role in fluid hemostasis and drug excretion. Drug-induced nephrotoxicity impairs intraglomerular hemodynamics, which affects 20% of the adult population in the United States ,2. MethoOur model provides a low-cost approach that can be used in the future to stratify the subpopulation of patients who respond differently to drugs or present distinct mechanisms of disease. These personalized glomerulus chips can be engineered as “you-on-a-chip” systems, to study different disease states and drug responses, treatment comparisons, and dosage optimizations for patients with debilitating kidney-related chronic conditions such as hereditary podocytopathies, cardio-renal diseases, and immunological effects of organ transplantation. Patients with rare genetic nephropathies could benefit from these injury/disease-on-a-chip methods to help unveil developmental mechanisms and identify novel treatment options. Additionally, acquired diseases, such as cardiorenal- and kidney-brain axis neurological disorders are becoming more relevant with the increase in epidemiologic data on CKD and related secondary disorders ,43. The


The success of immunotherapy was overshadowed by its low response rate, and the hot or cold tumor microenvironment was reported to be responsible for it. However, due to the lack of an appropriate method, it is still a huge challenge for researchers to understand the molecular differences between hot and cold tumor microenvironments. Further research is needed to gain deeper insight into the molecular characteristics of the hot/cold tumor microenvironment. A large-scale clinical cohort and single-cell RNA-seq technology were used to identify the molecular characteristics of inflamed or noninflamed tumors. With single-cell RNA sequencing technology, we provided a novel method to dissect the tumor microenvironment into a hot/cold tumor microenvironment to help us understand the molecular differences between hot and cold tumor microenvironments. Compared with cold tumors, hot tumors highly expressed B cell-related genes, such as MS4A1 and CXCR5, neurogenesis-related miRNA such as MIR650, and immune molecule-related lncRNA such as MIR155HG and LINC00426. In cold tumors, the expression of genes related to multiple biological processes, such as the neural system, was significantly upregulated, and methylome analysis indicated that the promoter methylation level of genes related to neurogenesis was significantly reduced. Finally, we investigated the pan-cancer prognostic value of the cold/hot microenvironment and performed pharmacogenomic analysis to predict potential drugs that may have the potential to convert the cold microenvironment into a hot microenvironment. Our study reveals the multiomics characteristics of cold/hot microenvironments. These molecular characteristics may contribute to the understanding of immune exclusion and the development of microenvironment-targeted therapy. Clinical trials of anti-PD-1 for patients with melanoma have demonstrated substantial therapeutic responses. Despite these encouraging clinical results, only a fraction of patients can benefit from immunotherapy3.The recent clinical successes of immunotherapy, including immune checkpoint inhibitors and adoptive cell therapy, represent a turning point in cancer treatment5. The inflammatory tumor microenvironment was characterized by rich infiltration of immune cells. These tumors are correlated with significant tumor regression when treated by immunotherapy10. However, due to the lack of appropriate experimental methods, how different tumor cells shape their TME, thereby determining their response to therapy, remains a critical unsolved problem.Recent studies suggest that the phenotype of the tumor microenvironment (TME) is a critical factor influencing the efficacy of immunotherapy. From here, the tumor microenvironment can be broadly categorized as an inflamed (hot) or noninflamed (cold) tumor microenvironment14, we identified multiomics molecular alterations in the inflamed/noninflamed tumor microenvironment. Unexpectedly, we found that the multiomics characteristics of neurogenesis-related genes were dysregulated in a cold microenvironment. However, it is interesting that a similar discovery has been reported in recent studies. Balanis et al. reported that these neuroendocrine-related molecular characteristics were unexpectedly found in hematological malignancies and correlated with treatment resistance15. Pathologically, neuroendocrine tumors are a rare tumor subtype that originate from a variety of tissues, including small cell lung cancer and neuroendocrine prostate cancer15. Previous studies have revealed that neuroendocrine tumors exhibit an “immune desert” microenvironment16. Our results suggested that neuroendocrine-related molecular alterations may be more widespread than we previously thought, although most tumors cannot be classified into this subtype based on the recent pathological definition.Here, based on single-cell RNA sequencing technology, a powerful tool to dissect the complexity of the tumor microenvironmentBefore classifying the tumor microenvironment as hot/cold, we needed to obtain a set of tumor-infiltrating immune cell gene markers to estimate the immune cell infiltration of each tumor sample Fig. .Fig. 1Ac17 to estimate the immune cell-level score of tumor samples. Finally, based on the unsupervised clustering pattern (immune cell scores) of tumor samples, we classified tumor samples into the high immune score (inflamed)/median immune score/low immune score (noninflamed). The unsupervised clustering results are shown in Fig. 18 and copy number variant (CNV) data19 to validate the unsupervised clustering results  mRNA ranging from 9 to 355; downregulated (inflamed-specific) mRNA ranging from 355 to 1024). Among them, downregulated mRNA (inflamed tumor-specific) represents the most striking signature that accounts for major differences between inflamed TME and noninflamed TME Fig. .21.For example, several genes involved in B cell-associated immune processes were biased in most tumor types Fig. , includiMore systematic functional insight into the inflamed/noninflamed TME demonstrated that genes involved in the neuronal system, extracellular matrix degradation, biological oxidation, and IGFBP-associated pathways were more likely to be upregulated in the noninflamed TME but varied across tumor types Fig. . In contTo further investigate the effect of the inflamed TME on noncoding RNA expression, we identified miRNAs and lncRNAs that were differentially expressed between the inflamed TME and the noninflamed TME. As shown in Fig. Further analysis revealed that hsa-miR-650 may inhibit the neurotrophic signaling pathway and axon guidance Fig.  by inhibIn terms of lncRNAs, lncRNAs including MIR155HG and LINC00426 were upregulated in the inflamed TME Fig. .Coexpression analysis revealed that these lncRNAs were positively associated with T-helper cell differentiation and cytokine signaling pathways Fig. , such asAlteration of DNA methylation is an important epigenetic mechanism that results in the dysregulation of RNA. Therefore, we further investigated the alteration of DNA methylation between inflamed and noninflamed tumors. As shown in Fig. Interestingly, consistent with the mRNA and noncoding RNA results, we found that different methylated regions (hypomethylated in noninflamed tumors) were related to the neuronal system and GABAB receptor-associated pathways, which suggested that methylation-level dysregulation of neuronal genes may be relevant to the formation of an inflamed/noninflamed tumor microenvironment Fig. . In term4.Despite the limited understanding of why the response rate of immunotherapy is unsatisfactory, it is increasingly clear that combination immunotherapy with classical therapy is the most feasible way to improve the response rate of immunotherapy4. However, limited by classical methods, a systemic understanding of hot/cold tumor microenvironment genomic characteristics is still limited, which constrains related drug discovery with big data22.Combination immunotherapy with classical therapy is considered the most feasible way to improve the response rate of immunotherapy25, we identified multiple drugs that may have the potential to convert a noninflamed environment into an inflamed tumor environment  are regarded as promising drug candidates by combining them with immunotherapy33, and moxonidine37, β-escin39 and AH2384846 have shown potential in cytokine signaling modulation and inflammation regulation in published reports. However, whether these drugs can directly affect antitumor immunity in vivo and whether they can enhance the effect of immunotherapy still need to be further explored.As shown in Fig. In total, our method provides an efficient way to identify robust molecular signatures of the tumor microenvironment. These molecular characteristics may serve as efficient resources and provide an opportunity for related drug discovery.To explore the prognostic significance of the identified noncoding RNAs and immune subtypes, univariate/multivariate Cox models and Kaplan–Meier analyses were performed. Kaplan–Meier analysis revealed that these noncoding RNAs  were positively associated with better overall survival (OS) in BRCA, LUAD, HNSC, and SKCM Fig. . The uniConsidering the favorable role of these noncoding RNAs and their potential to regulate the tumor immune microenvironment, further investigation of these noncoding RNAs may be helpful to elucidate the role of noncoding RNAs in the tumor immune microenvironment.We further investigated the prognostic role of immunophenotypes across tumor types. As shown in Fig. 47. Our results may provide some mechanistic insights for this persistent unsolved problem. Here, we found that neurogenesis-associated multiomics characteristics were significantly dysregulated between noninflamed and inflamed tumor microenvironments, which is interesting and complements previous reports. For example, Nikolas G Balanis et al. reported that a neuroendocrine phenotype existed in multiple hematological malignancies, and transdifferentiation into a neuroendocrine phenotype conferred treatment resistance to tumors15. Our results indicated that neurogenesis-related genes were also dysregulated in a variety of solid tumors and may be modified in various ways, including noncoding RNA and methylation. For example, miR-650, which is downregulated in noninflamed tumors, may enhance the expression of neurogenesis-related genes in the cold tumor microenvironment. The promoters of multiple neurogenesis-associated genes were hypomethylated in multiple noninflamed tumors48.Neuroendocrine-related molecular characteristics have been reported in some tumors, but little is known about how the tumor genome shapes itOur studies also revealed that lncRNAs may act as general regulators in the inflamed tumor microenvironment. The expression of MIR155HG and LINC00426 was altered in pan-cancer, and the coexpressed genes of MIR155HG and LINC00426 were involved in multiple immune-associated biological processes, including immune cell differentiation and exhausted/activated T-cell genetic programs, indicating that these lncRNAs might assist in the maintenance of the inflamed tumor microenvironment across tumor types, especially MIR155HG, which is an inflamed TME-specific gene in all analyzed tumor types.49. Third, our study provided a comprehensive catalog of molecular alterations, but we could not further investigate the role of the identified molecule due to the lack of funding support and the experimental environment. Therefore, further studies are necessary to elucidate the detailed role of these molecular characteristics.This study has some limitations. First, validation in other tumor types or a large cohort is warranted in further studies. Second, TCGA does not provide direct information on the tumor microenvironment. Therefore, we had to indirectly infer the relative score of the immune composition as described in previous studiesIn conclusion, our study identified multiple molecular differences between inflamed and noninflamed TMEs. These results provide comprehensive insights into the inflamed tumor microenvironment-related molecular mechanisms and have profound clinical implications. These results may help to optimize current combination immunotherapy to benefit more tumor patients.Nevertheless, our study calls attention to the need to include tumor microenvironment status in future clinical trials.50. Healthy controls of GSE62944 were excluded in this study. Updated clinical data and DNA methylation data were downloaded from TCGAbiolinks53. The raw count data of RNA sequencing were normalized and quantitated by the edgeR package54. The immunotherapy clinical cohort was from Riaz et al.55 and Cloughesy et al.56. The clinical data of patients involved in this study was based on open-Access database, so the ethical declaration is not appliable. But patients in these databases have obtained ethical approval, all information about ethical approval of these open-Access databases can be obtained from GDC portal (https://docs.gdc.cancer.gov/).RNA sequencing datasets, including mRNA expression, miRNA, and lncRNA, were downloaded from the GEO database with accession number GSE6294457. This dataset contains 4645 single cells isolated from 19 patients and profiles of immune and malignant cells within the tumor microenvironment. We applied the Seurat58 package to normalize the data and identify differentially expressed genes. Cells with unique feature counts over 10,000 or less than 1000 (these thresholds were determined by the QC metrics of Seurat) and features detected in less than three cells were excluded. tSNE was used for dimension reduction. Each cell is represented as a dot in a two-dimensional tSNE plane. The annotation of cells was annotated based on Guo et al.59 and the CellMarker database60. Gene signatures of immune cells were selected according to the following workflow (taking B cells as an example). First, markers of B cells should be positively correlated with B cells and statistically significant . Then, to make sure that these markers are as highly expressed as possible in B cells and as lowly expressed as possible in malignant and other immune cells, we sorted the markers identified in the above step in decreasing order of the absolute value of PCTB_cells-PCT malignant and the absolute value of PCTB_cells-PCT malignant . The top 1% of gene markers in the sorted list with the highest absolute value of PCT difference were regarded as B cell-specific molecular markers.Raw single-cell RNA sequencing data were downloaded from the GEO database with accession number GSE7205617 to calculate the immune score for each immune cell type. The GSVA algorithm has been proven to be an efficient way to reveal the characteristics of the tumor microenvironment49. Then, tumor samples were classified into the low immune score (noninflamed), median immune score, and high immune score (inflamed) TME groups based on the unsupervised clustering pattern of the immune score by optCluster61. To avoid confounding factors from potential mixtures, we excluded samples from the median immune score from further analysis. We also used methylation data 18 and CNV data 19 to estimate immune cell infiltration.To investigate the molecular characteristics of inflamed or noninflamed immunophenotypes, immune cell signatures identified in the above single-cell RNA sequencing data were used as input for the GSVA algorithmThen, we compared the molecular data between these two groups to identify molecular differences.54 package was used to perform differential gene expression analyses with the raw count matrix of TCGA data. The statistically significant criteria for each molecular characteristic were as follows: molecular characteristics  with an absolute value of the log fold change >1.5 and FDR P value < 0.05 were considered significant. To ensure that these molecules could represent pan-cancer dysregulated characteristics, we only included molecular characteristics differentially expressed in at least four tumor types. We next calculated Spearman’s correlation coefficient between identified noncoding RNAs and coding RNAs. Potential coding RNA targets were selected based on the following criteria: lncRNAs: significantly correlated mRNAs (FDR < 0.05) of lncRNAs were ranked with the average absolute value of Spearman’s correlation coefficient in decreasing order, and the top 1% of mRNAs (with the highest correlation coefficient) in this list were regarded as potential targets of lncRNAs. miRNAs: potential targets of miRNAs62 (from fourteen miRNA-mRNA interaction databases) and negatively correlated with the expression of miRNA (Spearman’s correlation coefficient <0 and FDR < 0.05). Functional enrichment analysis  of potential targets was performed to contribute to the mechanistic understanding of identified noncoding RNAs63.The EdgeR64 pipeline based on the following criteria66: (1) adjusted P value <0.05; and (2) absolute value of beta-value differences >0.1.In methylation analysis, only CpG probes mapped at promoter regions  were included in this analysis. Differently expressed regions were identified by a champ67. The data download and connectivity score calculation were performed with PharmacoGx68.Combination immunotherapy is considered the most efficient way to aid current immunotherapy. Here, transcriptomic differences between inflamed and noninflamed tumors were used as an input to calculate the connectivity score between transcriptomic differences and drug-induced genomic alterations. Drug-induced systematic genomic alterations were obtained from the CMAP database69.The chi-square test was used for statistical tests of categorical variables. Kaplan–Meier analysis and log-rank tests were used to test the survival differences between identified groups. The optimal cutoff point of continuous variables was determined by the surv_cutpoint function in the survminer packageThe univariate Cox proportional hazard ratio was used to calculate the hazard ratio of the factor of interest. The multivariate Cox proportional hazard model was used to test the independence of variates. All statistical analyses were performed by R 3.61.Further information on research design is available in the Supplementary InformationSupplementary Data 1Supplementary Data 2Reporting Summary


Displacement or seeding of malignant cells into the needle tract following percutaneous biopsy is a known phenomenon, although it does not affect disease recurrence or overall survival of patients with breast cancer. It has, however, been previously hypothesized that needle tract seeding may occasionally progress to clinical tumor recurrence, and there have been case reports of breast cancer recurrence that are likely to be related to needle tract seeding. We are presenting a case of invasive mucinous carcinoma of the breast with associated malignant cell seeding within the biopsy tract, which was diagnosed preoperatively on contrast-enhanced MR imaging. A needle tract can often be visualized on contrast-enhanced MRI post biopsy and these changes may reflect tissue damage and regeneration only. In our case, an unusual nodular enhancement pattern was demonstrated along the biopsy needle tract, which was consistent with the histopathological finding of tumor seeding. Percutaneous image-guided core biopsy is an established diagnostic tool for breast abnormalities with radiological appearances indeterminate or suspicious for malignancy . DisplacWe are presenting a case of invasive mucinous carcinoma of the breast with associated malignant cell seeding within the biopsy tract, which was diagnosed preoperatively on contrast-enhanced MR imaging.A 71-year-old female patient was presented with an approximately 3 cm peri-areolar mass in the 12 o’clock position in her right breast on physical examination, with no nipple retraction, skin dimpling or palpable axillary lumps. Bilateral mammograms showed very dense breast tissue with a suggestion of an asymmetric density in the right retro-areolar area. It was however difficult to characterize the lesion due to increased breast density Figures , 1B. SubPrevious studies investigated the incidence of tumor cell displacement along the biopsy needle tract in surgical specimens from patients with breast cancer, which showed that tumor seeding is present in 22%-50% of cases -10. The It has been widely accepted that tumor seeding along the needle tract causes no increased recurrence rate when patients received appropriate adjuvant treatment ,13. TherIshizuna et al. reported a case similar to ours, where the biopsy tract was visible on preoperative breast MRI and the authors hypothesized that enhancement along the biopsy tract could indicate tumor seeding . A recenTumor cell seeding in the needle tract following percutaneous core biopsy of breast cancer can rarely progress into clinical disease recurrence. If there is, however, a clinical suspicion, contrast-enhanced MRI of the breast could be the imaging method of choice to detect tumor seeding in the biopsy needle tract, even preoperatively.In case of typical radiological presentation of mucinous carcinoma, we should consider using a vacuum-assisted biopsy device, trocar technique or fewer needle passes with a regular spring-loaded biopsy approach to minimize the risk of tumor seeding.


The prevalence of photosynthesis, as the major natural solar energy transduction mechanism or biophotovoltaics (BPV), has always intrigued mankind. Over the last decades, we have learned to extract this renewable energy through continuously improving solid-state semiconductive devices, such as the photovoltaic solar cell. Direct utilization of plant-based BPVs has, however, been almost impracticable so far. Nevertheless, the electrochemical platform of fuel cells (FCs) relying on redox potentials of algae suspensions or biofilms on functionalized anode materials has in recent years increasingly been demonstrated to produce clean or carbon-negative electrical power generators. Interestingly, these algal BPVs offer unparalleled advantages, including carbon sequestration, bioremediation and biomass harvesting, while producing electricity. The development of high performance and durable BPVs is dependent on upgraded anode materials with electrochemically dynamic nanostructures. However, the current challenges in the optimization of anode materials remain significant barriers towards the development of commercially viable technology. In this context, two-dimensional (2D) graphene-based carbonaceous material has widely been exploited in such FCs due to its flexible surface functionalization properties. Attempts to economically improve power outputs have, however, been futile owing to molecular scale disorders that limit efficient charge coupling for maximum power generation within the anodic films. Recently, Langmuir–Blodgett (LB) film has been substantiated as an efficacious film-forming technique to tackle the above limitations of algal BPVs; however, the aforesaid technology remains vastly untapped in BPVs. An in-depth electromechanistic view of the fabrication of LB films and their electron transference mechanisms is of huge significance for the scalability of BPVs. However, an inclusive review of LB films applicable to BPVs has yet to be undertaken, prohibiting futuristic applications. Consequently, we report an inclusive description of a contextual outline, functional principles, the LB film-formation mechanism, recent endeavors in developing LB films and acute encounters with prevailing BPV anode materials. Furthermore, the research and scale-up challenges relating to LB film-integrated BPVs are presented along with innovative perceptions of how to improve their practicability in scale-up processes. In this line, sustainable energy generation using BPV fuel cells (FCs) has currently attracted research and development endeavors owing to its advantageous characteristics, including carbon sequestration, bioremediation and biomass production ,2. Furthd oxygen , while tThe power generation efficacy of algae-based BPVs is significantly influenced by the anode material and its functionalization. Graphene (periodic arrays of densely packed carbon atoms in a 2D honeycomb structure) and its derivatives of graphene oxide (GO) and reduced graphene oxide (rGO) have been considered as excellent anode materials owing to their constructive characteristics, including lower thickness, high mechanical stability, optical transparency, etc. Specifically, the graphene-based thin films demonstrate a higher degree of geometric order and a large surface area, resulting in the desirable electronic properties that could be utilized in state-of-the-art electronics . DerivatGraphene-based thin films have therefore found various applications in electronics, photonics, energy generation and storage and in biology and medicine ,27,28,29The LB method involves suspending amphiphilic molecules in a liquid subphase, generally deionized water, which spontaneously spread to form a monolayer or Langmuir film. With the use of moving barriers, these floating molecules are further compressed to form a solid-state monolayer film that can be transferred onto a solid substrate with the aid of a dipping process. Traditionally used to assemble homogenous organic and inorganic 2D thin films, structures formed using the LB method exhibit exceptionally higher degrees of geometric order, resulting in superior electronic properties, which are not achievable using other methods ,32,33. UFabrication of graphene-based anodes as biocompatible materials, especially using the LB technique, may therefore assist the development of algal BPV platforms for improved power outputs. Although adequate literature is available for thin films generated by the LB technique for FCs, there is not as yet an approachable guide that addresses and tackles the chief issues hampering the evolution of practical BPVs. Therefore, the current review aims to provide a compact yet descriptive discussion pertaining to the most recent achievements in the research and development of algal BPV FCs based on LB-assisted graphene-based anode materials.In general, certain properties are required when it comes to anodes for algae-based and microbial fuel cells (MFCs), prioritized by good biocompatibility, large surface area, high chemical, thermal and mechanical stability and high conductivity. So far, major improvements have been achieved by means of modifying the available anodes applied in FCs, especially in terms of power generation. This remains a challenge, though, since the various methods employed in anode fabrication do not have or have only limited flexibility as is necessary to allow a wide range of modifications for optimizing the anode in order to cater for the many different types of microalgae utilized for BPVs, bioremediation, etc. A good overview of the recent advances in anodes, especially for MFCs, can be found in the following review article by Yaqoob and co-workers . Figure Conventional anodes are generally optimized for mainstream FC applications which relate to non-biological photovoltaic devices. While great progress in this aspect has contributed towards improved anode performances, specific functionalization  must be adhered to when it comes to BPVs, such as those involving microalgae. Most important is the adhesion and/or biocompatibility of the anodes towards algae, achieved by means of optimizing anode porosity and control of functional groups. Understanding the properties of the selected algal species, such as their size, enables the fabrication of anodes with corresponding pore sizes and functional groups. In a previous work, the LB technique was employed successfully to allow flexibility in controlling pore sizes which accounted for the improved charge transferability by means of high surface area and algae adhesion . The LB The LB technique is a popular method due to its innate ability to produce large areas of highly uniform thin films, in addition to allowing the re-engineering and manipulation of structures on nano- and microscales ,34,37 to2 carbon, while the O group binding with the basal plane confers hydrophilic properties [GO is generally preferred for producing LB films compared to graphene due to its natural amphiphilic properties . The hydoperties . GO has operties . This amoperties . An isotherm graph, which is typically a surface pressure versus area profile, generated upon compression of the GO monolayer on top of the water subphase is monitored using a tensiometer . The sloThe monolayer is inclined to disrupt into multilayers around the edges due to the flexibility of the soft edges of the GO sheet. However, the central area of the GO sheet in general remains flat without much wrinkling or folding. The folding effect at the edge of the GO may be described by the effect of the slightly lower gradient of the isotherm graph representing the region in (c). Continuous compression finally pushes the LB film to breaking point at which the GO sheets start to buckle, wrinkle, overlap and/or partially overlap . SmallerThe final step in the formation of 2D graphene-based film is the transfer and deposition of the GO layer or film onto a solid substrate using the dipping process. This method, however, proves challenging for producing thin films of large area ,44. HencTraditional and manipulated LB deposition methods have been reported to yield high-quality and large 2D rGO or GO thin films. The traditional method involves vertical dipping of the substrate through a water subphase during the close-packing arrangement of rGO sheets . For effThe traditional method can be manipulated in several ways to deposit large-area 2D GO films. Xu and co-workers demonstrated a controlled edge-to-edge assembly of a floating 2D GO monolayer with the ability to yield large-area films . The metThe mechanism of controlled edge-to-edge assembly contributes to barrier-free densification, the aggregation mechanism and spreading-induced film. The barrier-free densification of the LB film is accomplished by using repetitive dripping deposition of 0.025 mg/mL GO dispersion at the air–water interface. This method proves to be nearly 100% efficient in transferring a GO monolayer onto a large-area substrate at the air–water interface and is attributed to the immersion forces that occur while the spreading solvent evaporates. The aggregation mechanism is carried out by depositing GO dispersion at a low pH onto a highly ionic subphase, which results in the shielding of repulsive electrostatic forces between individual GO sheets. Spreading-induced film densification is achieved by spreading solvent at a suitable distance-dependent force from floating GO films. Compression of barriers will then effectively assist to form a densely tiled film. The distance-dependent force is transmitted throughout the LB trough dissimilarly depending on whether the interaction between the sheets is governed by repulsive or attractive forces. Using this mechanism, a continuous deposition of 2D GO film onto a large-area substrate for coating and patterning using roll-to-roll deposition was achieved . In anotThree-dimensional graphene-based materials, meanwhile, are of particular interest due to their intrinsic properties similar to 2D graphene sheets while they also have the added benefits of increased surface areas combining meso-, macro- and micropores. The meso- and microporosity display a highly specific area and macroporosity significantly improves the catalytic performance at the surface region . These 3In a recent report, an unconventional approach was employed using the LB method for preparing 3D rGO films . While dAnnealing at 60 °C between each consecutive deposition of layers helps to create higher surface roughness and improves the porosity of the 3D structures. It was reported that at the sixth deposition layer of rGO, complex interconnected micrometer-scale porous structures were achieved which enabled enhanced integration and encapsulation of microalgae within BPV FCs for increased power output . At highSynechocystis sp. and a sub-cellular photosynthetic membrane (the thylakoid from Spinaciaoleracea L.) for comparison of relative lifespan and power output [−1) compared to Synechocystis sp. (4.10 nW (nmolChl)−1). Regarding Synechocystis are cyanobacteria that produce microbial nanowires with pili-like structures , Sure 2015 reported that the amino acid sequence of these structures was composed of aromatic amino acids, which explained its conductive characteristics [Synechocystis sp. on an alloy anode in a microfluidic BPV device was achieved, which generated a power output of 294 mW m−2 [Bombelli and co-workers used two types of photosynthetic materials: a whole cell of r output . The suberistics . In anot4 mW m−2 . Chlorella sorokiniana [−1·day−1 for 35 days. Prior to this, Nishio and co-workers had investigated the syntrophic relationship between green algae and heterotrophic bacteria in a photosynthetic microbial FC [Chlamydomonas reinhardtii and Geobactersulfur reducensi growing on an anode (graphite felt) and carbon cloth coated with platinum (0.5 mg m−2) as the cathode achieved a power output of 9.2 mW m−2. The authors concluded that excretion of organic compounds by the algae resulted in the bottleneck in the electricity conversion process. Bateson and co-workers, meanwhile, fabricated a bio-bottle-voltaic (BBV) device built from recycled plastic bottles and a recycled aluminium (Al) anode using green alga, okiniana . The sysobial FC . In thisThe power outputs generated by algal BPV FCs are in general lower than conventional FCs. Accordingly, exogenous mediators have been used to counter the low power output by facilitating the electron transfer from the algae to the anode and reduce intrinsic metabolic losses and intracellular competition for energy resources ,57,60. HChlorella UMACC 051 (0.112 mWm−2), Spirulina UMACC 159 (0.121 mWm−2), Chlorella UMACC 313 (0.124 mWm−2) and Synechococcus elongates UMACC 105 (0.313 mWm−2), generated the highest power densities among a number of species studied. In a work carried out in our laboratory, photosynthetically active algae immobilized in alginate gel were used to form an alginate–algal biofilm on an ITO anode  was used for the gelation process. Chlorella cells were embedded into the alginate matrix where compact colonies form upon cell division. This close-packed arrangement of the cells and its direct contact with the ITO anode reduced the liquid-phase mass transfer resistance, resulting in improved electron transportation [BPV devices comprising algal biofilms on anodes were found to produce a higher power density compared to algae suspension on anodes . Four alTO anode . A peak ortation . In terms of electrochemical properties, LB films of conjugated materials have been considered to be of prime interest in virtue of providing a mixed valence state of oxidation/reduction. Such materials demonstrate increased electrical conductivity owing to a partially oxidized or reduced state. Generally, well-ordered LB films demonstrate slow electrochemical redox reactions and electroactivity compared to non-well-ordered multilayer assemblies because LB films with small mean molecular areas favor diffusion-controlled voltammetry. The hindered electrochemical activity for multilayer LB films may have originated as a result of the formation of empty spaces between the hydrophobic chains due to surface tension effects. From a theoretical point of view, LB films attain vectorial electron transfer with an electron diffusion coefficient value of two orders of magnitude in comparison with multilayer and heterolayer films. The organized mono- and multilayers of LB films are therefore more importance for gaining insights into the interfacial electron transfer reactions . The LB Few studies in the literature have reported the electrochemical properties of LB films in biological FCs and only recently has there been some interest in this aspect. Jaffar and co-workers investigated the electrical properties of 3D rGO thin films integrated within a BPV FC and their interfacial electrochemical properties . It was Chlorella sp. was grown on the treated rGO anode (100 W plasma power), improved power density of 6.94 × 105 W/m2 was obtained. A maximum surface roughness of 0.226 µm was achieved at 140 W of plasma power. Plasma treatment increased the adhesion of LB rGO layers on the glass substrate allowing substantially better biocompatibility with the microalgae, as evidenced by the cyclic voltammetry and chronoamperometric studies. The plasma-treated rGO anodes exhibited higher conductivity, porosity and surface roughness, which are the main contributing factors for BPV efficiency. The glass/rGO showed a prompt oxidation peak, observed at 0.87 V vs. Ag/AgCl, along with an improved oxidation current, which guarantees the presence of electroactive species/proteins located in the surface of Chlorella sp. under illumination. The increased anodic oxidation current under light conditions may have been established by the breakdown of intracellular metabolites and/or electron transfer to the photosynthetic chain by virtue of photosynthetic water splitting. Ng and co-workers meanwhile reported that an rGO anode in an algal BPV platform improved maximum power efficiency (0.141 mW/m2) against standard ITO anodes due to its intrinsic electrical properties and biological compatibility for microalgae [In another work, Ibrahim and co-workers utilized the LB method for the deposition of rGO films prior to plasma treatment by varying the plasma power . As a recroalgae . 2) to produce carbohydrates which effectively remove carbon from the environment. No harmful by-products are produced; further photosynthesis-based FCs release oxygen gas (O2) upon the photolysis of water molecules, contributing to healthy environmental oxygen level in terms of O2:CO2 ratios. BPVs have also been utilized successfully for bioremediation applications, with researchers developing algae-based BPV platforms for treating palm oil mill effluent (POME), wastewater and other substances. As such, the development of BPV-based FCs offers a comprehensive approach to renewable power generation superior even to solar cell technology, which validates continuous concentrated efforts. Therefore, the exciting prospects of producing clean green energy and/or biomass production while integrating bioremediation and wastewater treatment processes in a single platform is of immense interest in terms of global energy demands and climate change crisis.It could be understood that currently photosynthetic-based FCs significantly lags behind conventional FCs in terms of power generation. There are, however, advantages exclusive to BPV-based FCs, the most important of which is their carbon-negative nature. During BPV operation, electrons are produced through the photolysis of water molecules during photosynthesis and extracted by means of an external circuit for power generation. The liberated protons or the hydrogen atoms are later used to fix carbon atoms from carbon dioxide (CO


We present the case of a young adult female who presented to rheumatology with persistent arthralgia of her knees despite disease-modifying anti-rheumatic drugs (DMARDs) for seronegative inflammatory arthritis. Her magnetic resonance imaging (MRI) of her knees demonstrated bone lesions compatible with chronic recurrent multifocal osteomyelitis (CRMO). CRMO is a rare autoinflammatory condition of the bone, typically affecting younger female patients. It is characterised by the presence of multifocal inflammatory bone lesions, often affecting the metaphyses of long bones. It can present with localised pain and swelling, and such as in this case, joint swelling.An 18-year-old female patient presented to rheumatology in October 2019 with a 4-week history of left knee monoarthritis.Due to a history of a preceding upper respiratory tract infection, oral non-steroidal anti-inflammatories (NSAIDs) were commenced for possible reactive arthritis. She had no history of seronegative features of psoriasis, uveitis, inflammatory bowel disease, pustulosis or acne.Over the next 4 weeks, she experienced intermittent episodic bilateral knee effusions associated with elevated inflammatory markers. C-reactive protein (CRP) peaked at 232mg/L and erythrocyte sediment rate (ESR) at 57mm/1hr. Rheumatoid factor, anti-cyclic citrullinated peptide (CCP) antibodies and antinuclear antibody (ANA) were negative. Plain X-rays of the knees were normal.  MRI of the right knee and hip in October 2019 were reported as normal. An ultrasound scan of the right knee in December 2019 between episodes of swelling, was normal.She continued to experience persistent knee and right hip arthralgia, with stiffness and limitation of knee flexion. DMARD treatment was commenced in December 2019 due to intermittent synovitis of the knees. Inflammation in the knees persisted despite treatment with oral Methotrexate. The additional Sulfasalazine was discontinued due to neutropaenia. Etanercept  was commenced in November 2020 with good clinical and biochemical response. However, despite resolution of knee effusions, knee arthralgia persisted with stiffness and limited knee flexion. Repeat MRI imaging revealed multiple areas of hypointense signal surrounding central areas of hyperintense signal. These are characteristic of CRMO. On review of the initial right knee MRI from October 2019, it was noted that subtle lesions were visible. Bone turnover markers were checked; beta-crosslaps was 573ng/L and type 1 procollagen peptide was 59.7ug/L. The patient has now begun a 1-year treatment course of IV pamidronate in addition to continuing her methotrexate and Benepali.CRMO is a rare condition, affecting approximately 4 per million. It typically affects children, more commonly females. Although the most common presenting symptoms are pain and local tenderness, patients may also report warmth and localised swelling. Systemic features can occur, albeit rarely. Although it can affect multiple sites, including the spine, the metaphyses of long bones are commonly involved.CRMO is a non-infectious autoinflammatory bone disorder, thought to be due to abnormal production of pro- and anti-inflammatory cytokines, which in turn affect the activation of osteoclasts within bone. Although plain X-rays may be normal, they may show evidence of osteolytic lesions or sclerosis later in the disease process. MRI is the preferred imaging modality and can demonstrate areas of bone marrow oedema and periostitis.The MRIs of this patient showed multiple large geographic lesions bilaterally demonstrating hypointense signal peripherally with central areas of hyperintense (high) signal. Both the epiphyses and metaphyses of the long bones were affected, which is characteristic of CRMO.  Similar appearances could be seen in bone infarcts, for example in sickle cell disease; however, these would usually only affect the metaphyses of bone. Although the previous imaging was reported to be unremarkable, some subtle lesions can be seen.This patient’s isotope bone scan revealed non-specific uptake in the knees and shoulders, rather than localised areas of uptake which are typical in CRMO. A bone biopsy can differentiate CRMO from important differentials such as infective osteomyelitis and malignancy. In this patient, a bone biopsy was discussed but not undertaken as there was widespread involvement with no clear satellite lesion.Management of CRMO encompasses a variety of treatments, including NSAIDs, steroids, DMARDs and bisphosphonates largely based upon smaller trials. Due to ongoing symptoms despite conventional synthetic and biologic DMARDs, in this patient IV pamidronate treatment was commenced. This case highlights the importance of considering CRMO in young adult patients with seronegative arthritis who do not respond to standard therapy.There were no identifiable features of bone inflammation on either plain X-rays or knee ultrasound and no reported features on the initial MRI of the right knee. This case reinforces the need for multidisciplinary team discussion with an experienced specialist musculoskeletal radiologist, especially when symptoms are discordant from the clinical examination findings, posing diagnostic uncertainty. In this case, it transpired that evidence of CRMO could be seen on the initial MRI which was taken approximately 18 months before the diagnosis was made.  Given that this patient had active bone inflammation despite treatment with conventional synthetic and biologic DMARDs, she was commenced on intravenous bisphosphonates which inhibit osteoclastic activity and can reduce inflammatory cytokine production. Bisphosphonates can cross the placenta and potentially impair normal bone development in utero.  This can pose a management challenge in young adult females of child-bearing age.Pamidronate has been shown to be useful in cases of SAPHO ; a related condition where non-infectious osteomyelitis is associated with dermatological manifestations of acne and pustulosis. Treatment response can be monitored by clinical improvement and by biochemical markers of bone turnover, such as beta-crosslaps and type 1 procollagen peptide (P1NP).In this case, the patient was found to be vitamin D deplete and required replacement therapy prior to pamidronate therapy. After initiating treatment, bone turnover markers have reduced although arthralgia persists. A 1-year treatment course has been planned with a repeat MRI to reassess radiological response at that time.