Central airway obstruction caused by cancer requires urgent interventional pulmonology. Malignant main carinal involvement is one of the most challenging situations, usually treated by rigid bronchoscopic intervention under general anaesthesia. However, these patients tend to be in poor condition due to underlying malignancy. Therefore, less‐invasive strategies are needed. Six patients with lung cancer exhibiting malignant carinal involvement treated using the ‘side‐by‐side’ method of bilateral self‐expandable metallic stents using fibre‐optic bronchoscopy under topical anaesthesia were retrospectively investigated. The median procedure time was 29.5 min (range: 23–38), and the palliation of dyspnoea was achieved in all cases. The median survival time after intervention was 58.5 days (range: 23–172). The cause of death was acute coronary syndrome in two patients, aspiration pneumonia in two, upper gastrointestinal perforation in one, and catheter‐related blood stream infection in one. This strategy was less invasive and suitable for patients with poor performance status. Central airway obstruction (CAO) is critical and life‐threatening for cancer patients and is categorized as an oncological emergency that requires urgent intervention. Therapeutic bronchoscopy using mechanical debridement, brachytherapy, tumour ablation, or airway stent placement in inoperable lung cancer patients with symptomatic airway obstruction is recommended by the third edition of American College of Chest Physicians Evidence‐Based Clinical Practice Guidelines Malignant carinal involvement is considered one of the most difficult situations among CAO, which is usually treated by rigid bronchoscopic intervention under general anaesthesia. Laser treatment and mechanical debulking are usually applied to remove the tumour invasion, which are followed by Y stent placement to prevent tumour regrowth and strengthen airway patency The Dumon stent has been the most prevalent among silicone stents Patients with malignant carinal involvement tend to have a poor performance status (PS) due to disease progression; consequently, silicone stenting is not applicable in these patients. Thus, less‐invasive interventional strategies are urgently required.Self‐expandable metallic stents (SEMSs) have an outstanding advantage, namely, their convenient delivery using FOB under topical anaesthesia. Their conformability to the airway structure due to their self‐expansive characteristics is another advantage. On the other hand, the additional therapy to tumour ingrowth or overgrowth is limited, and SEMSs cannot be removed when they become unnecessary.The application of ‘side‐by‐side’ method of bilateral SEMSs has been reported in the management of malignant carinal involvement We retrospectively analysed six patients who were treated using this method in terms of effectiveness, tolerance, and safety of the procedure.A retrospective study was performed of patients with lung cancer who developed malignant carinal involvement and were treated using the ‘side‐by‐side’ method of bilateral SEMSs between 2013 and 2017.The indication criteria for bilateral SEMSs at our hospital are as follows: the airway stenosis is too severe for radiotherapy, which induces oedema of bronchial mucosa at the site of stenosis leading to the total occlusion in either of the mainstem bronchus; histology of non‐small‐cell lung cancer as its prognosis in response to chemotherapy is less encouraging compared to small cell lung cancer; and the rigid bronchoscopic intervention under general anaesthesia is not suitable due to poor PS or complications as decided by both anaesthesiologists and thoracic surgeons.The patients were numbered sequentially from 1 to 6, and individual data were managed according to the allocated number.A fibre‐optic bronchoscope was inserted after delivering 4% lidocaine by nebulizer, which was followed by an intravenous administration of midazolam at a dose of 0.06–0.1 mg/kg. Skin markers were placed at the level of carina and 3 cm rostral site. As the most critical sites were in the right mainstem bronchus (RMB) in all cases, a flexible 0.035‐in. guidewire  was inserted into the RMB, and a similar guidewire was subsequently inserted into the left  dyspnoea grade Stent patency and post‐procedure survival, as well as the cause of death, were collected from the medical records.Data are presented as median (range) for continuous variables.n = 3; grade 4, n = 3.The median age was 70.0 years (range: 66–91); one patient was female, and five were male. Two were former smokers, and four were current smokers. The histology was squamous cell carcinoma in four and adenocarcinoma without oncogenic driver mutation in two. The primary sites were right upper lobe in five patients and mediastinum in one. SEMSs had been placed in RMB before the procedure in two patients; then, the ‘stent in stent’ technique was utilized. The baseline mMRC dyspnoea grades were: grade 3, The median time needed for the entire procedure was 29.5 min (range: 23–38). There were no complications, including uncontrollable bleeding, bronchial perforation, pneumothorax, and respiratory failure.The representative chest coronal computed tomography (CT) images are shown in Figure The chest coronal CT images after the procedure in cases 1 and 3–6 are shown in Figure Subjective improvement in dyspnoea was observed in all cases. The mMRC dyspnoea grades were improved by −2 grades in three patients and −1 grade in three.The stent patency was confirmed at the time of death in five cases, while the occlusion was observed 14 days after the procedure in one case. The median time of stent patency and post‐procedure survival were 58.5 days (range: 14–172) and 58.5 days (range: 23–172), respectively.The causes of death were acute coronary syndrome in two patients, aspiration pneumonia in two, catheter‐related blood stream infection in one, and upper gastrointestinal perforation in one.Two patients chose bilateral SEMSs as best supportive care; thus, they did not receive any additional treatment. Four patients were treated with one regimen of cytotoxic chemotherapy; however, all of them refused further chemotherapy, and all of them died after the completion of the relevant chemotherapy. The chemotherapy regimens were as follows: carboplatin plus paclitaxel, carboplatin plus gemcitabine, carboplatin plus S‐1, and docetaxel plus ramucirumab in each.The application of the ‘side‐by‐side’ method of bilateral SEMSs to malignant carinal involvement was less invasive and safe under topical anaesthesia in all cases.Although rigid bronchoscopy is recommended and plays an important role in the management of CAO In terms of the palliation of suffocating symptoms, this procedure was quite effective in all cases, with a prompt improvement in mMRC dyspnoea grade. As the prognosis of patients suffering from malignant carinal involvement is poor, the palliation of symptoms should be considered important as a short‐term clinical benefit.On the other hand, stent patency and post‐procedure survival are also important as long‐term clinical benefits. The median time of stent patency and post‐procedure survival could be long enough considering the critical status at the time of bilateral SEMSs placement. Five patients demonstrated stent patency at the time of death, except one with stent occlusion after 14 days due to disease progression. Furthermore, the cause of death in six patients was not due to stent‐related issues but because of other causes irrelevant to the tumour progression. Thus, this procedure could be a strong strategy in the management of malignant carinal involvement with poor PS. Post‐procedure treatment with chemotherapy and general management including ischaemic heart disease are also crucial in the pursuit of longer overall survival.The median time of stent patency after the ‘side‐by‐side’ method was 58.5 days, while that after the Dumon Y‐stent was reported to be 133 days In an attempt using the less‐invasive strategies, a combination of two types of metallic stents The current study has several limitations. First, as this study was a retrospective observational investigation with a small sample size, the feasibility should be elucidated in prospective studies with larger populations. However, this could be difficult as malignant carinal involvement is one of the specific and rare forms of CAO. Thus, it is important to consider the efficacy as well as the risk and invasiveness of this method compared to Dumon Y‐stent according to the background of each case. The discussion by respiratory physicians, thoracic surgeons, radiotherapists, and anaesthesiologists is indispensable in such cases.In conclusion, the management of malignant carinal involvement using the ‘side‐by‐side’ method of bilateral SEMSs was effective and tolerable without any complication in cases of poor PS or with cardiovascular complications.This study was carried out in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of Uji‐Tokushukai Medical Center . Written informed consent was omitted as the study was retrospective, and patient anonymity was assured.


Colorectal cancer (CRC) is the second and third highest cause of cancer deaths among Canadian men and women, respectively. Population‐based screening through fecal occult blood testing (FOBT) has been proven to be effective in reducing CRC morbidity and mortality. Although participation in Ontario's organized CRC screening program has been increasing steadily since 2008, its uptake remains low among recent immigrant populations despite the known benefits of screening. To promote participation in CRC screening, it is imperative to understand both individual and system level barriers and enablers. Although a number of immigrant and nonimmigrant factors have been associated with low participation, there is a dearth of knowledge related to the religious affiliation in CRC screening uptake. Our study is among the first to examine this issue in Ontario, one of the most ethnically diverse Canadian provinces and preferred settlement destinations for immigrants.We conducted a population‐based retrospective cohort study using linked health care administrative databases. Our cohort included Ontario residents, age 50‐74 who were eligible for FOBT from 1 April 2013 to 31 March 2015.We found that immigrants from the Middle East and North Africa and Eastern Europe and Central Asia had the lowest rates of screening. Furthermore, being born in a Muslim‐majority country was associated with lower FOBT screening even after controlling for other confounders including world region and income  of screening 0.92 [95% CI 0.90‐0.93]). Moreover, being enrolled in a primary care model, having a female primary care provider and having an internationally trained physician were associated with increased screening among immigrants from Muslim‐majority countries.These findings can inform future efforts to improve screening uptake like: enhancing access to primary care providers and enrollment in primary care models, targeted FOBT education for male providers and providers not in a primary care model, development of culturally sensitive and appropriate educational materials, and use of interactive approaches for communication of cancer screening information. The FOBT screening uptake was low among immigrants from Muslim‐majority country. Immigrants from the Middle East and North Africa and Eastern Europe and Central Asia countries were at high risk of under‐screening. FOBT uptake was lower for people with no primary care provider and high income. Having a female primary care provider and having an internationally trained physician were associated with higher FOBT use among immigrants from Muslim majority countries. In Ontario, ColonCancerCheck (CCC), the province's organized population‐based screening program, offers FOBT every 2 years to asymptomatic adults aged 50‐74 years without a family history of CRC , followed by colonoscopy within 8 weeks in the event that the FOBT result is abnormal.Immigrants face more challenges than the general population in accessing screening services. Their health may take a back burner to settlement issues such as securing a job, finding affordable shelter, learning a new language, and creating social networks. Ontario is the most diverse and highly populated province in the country, and the preferred settlement destination for a considerable proportion of immigrants and refugees in Canada. More than half of Canadian immigrants and refugees reside in Ontario.Cancer screening literature that focusses on disparities for immigrants has highlighted a number of individual and system level factors associated with lower screening uptake such as limited economic power, language barriers, immigration status , world region of birth, limited knowledge about the benefits of preventive health care, lack of a primary care provider, not being enrolled in primary care practice, having a male or internationally trained physician, and inflexible clinic hours as being.We have previously examined cervical and breast cancer screening for women from Muslim‐majority countries, and found differences in screening uptake.Considering a higher influx of immigrants from Muslim‐majority countries from Asia and from Africa, and the fact that approximately 73% of Canadian Muslims live in Ontario, the main goal of this study was to examine the CRC screening uptake  and its predictors among immigrant Muslim and non‐Muslim majority countries residing in Ontario using country of birth and region of origin as a proxy for religious affiliation. The findings will help to understand the role of religious affiliation in cancer screening uptake.22.1We conducted a population‐based retrospective cohort study using multiple linked healthcare administrative databases at ICES, an independent nonprofit provincial research organization that houses population‐based health and administrative data. Databases at ICES were linked using unique encoded identifiers. This study falls under Section 45 of Ontario's Personal Health Information Protection Act which does not require Research Ethics Board Review. Section 45 authorizes health information custodians to disclose personal health information to a prescribed entity, like ICES, without consent.2.2Our study cohort was created by linking the Registered Persons Database (RPDB) and the Immigration, Refugees and Citizenship Canada database (IRCC) and included immigrant people aged 50‐74, who were eligible for the universal Ontario Health Insurance Plan (OHIP). The RPDB database contains the age, sex, and postal code of all Ontario residents who are eligible for Ontario's health insurance plan that covers healthcare expenses of all permanent residents and certain refugees. The IRCC database comprises demographic characteristics of landed immigrants and refugees in Canada since 1985.2.2.1The inclusion criteria consisted of people who: (a) were alive and eligible for health care coverage for the entire study period between 1 April 2013 and 31 March 2015; (b) were in the 50‐74 year age range during the study period; and (c) resided in Ontario. The targeted 50‐74 age group and 2‐year study period correspond to the recommended time line and eligibility criteria for FOBT as recommended by the CCC screening program.The exclusion criteria were people who (a) had a diagnosis of colorectal cancer or inflammatory bowel disease; (b) died prior to 31 March 2015; (c) were not continuously eligible for OHIP; and (d) did not have a documented country of birth.Figure 2.3Our dichotomous study outcome was adherence to FOBT screening during the study period (1 April 2013 to 31 March 2015). Physician claims submitted to OHIP were used to identify people who had undergone FOBT. The OHIP database includes billing and diagnostic information submitted by approximately 95% of Ontario's physicians.2.4The analysis included the following individual and system level variables that we hypothesized could influence the relationship between Muslim religion and FOBT use: age, sex, immigration class , language ability , neighborhood income (categorized into five quintiles—Q1 (lowest income) to Q5 (highest income), gender and location of training of the primary care physician , and type of primary care patient enrollment model (PEM) . Attachment to a primary care provider was assessed using data from the Client Agency Program Enrolment (CAPE) and the Corporate Providers' Databases which capture all Ontarians who are enrolled with a physician in a patient enrollment model (PEM). PEMs include alternate models of primary care delivery and physician disbursement ranging from independent physicians to group‐based multidisciplinary practices, capitation‐based blended payment to fee‐for‐service‐based blended payment and/or salary‐based blended payment with further financial incentives for promotion of cancer screening.2.5We used descriptive statistics to describe the study population by world region of origin and by Muslim and non‐Muslim‐ majority countries. Inferential analyses including both bivariate and multivariate Poisson with robust error variance were applied to examine FOBT use disparities between Muslim and non‐Muslim immigrants stratified by their region of origin, and to identify the predictors of nonadherence to CRC screening based on our study variables noted above. Region of origin was included as a variable in the overall regression model to diminish unmeasured confounders that might exist when comparing people from different regions of the world with different cultures and economies. We controlled for all study variables noted above. All statistical tests were performed using SAS version 9.4 (SAS Institute) and set at the two‐sided 5% level of significance.3The sociodemographic and clinical characteristics of Ontario immigrants aged 50‐74 years who were eligible for CRC screening (FOBT) are displayed in Table More than 50% of immigrants resided in the two lowest income quintile neighborhoods compared to Canadian long‐term residents , with those from Muslim‐majority countries being more likely to live in the lowest income quintile. Income variations existed across immigrants' region of origin with Sub‐Saharan Africans from Muslim Majority countries having the highest proportion of people living in the two lowest income quintiles (72%) followed by South Asia (51%), Europe and Central Asia (47%) and Middle Eastern and North African (39%). Less than 5% of immigrants resided in rural area compared to 16% of Canadian long‐term residents. The proportion of immigrants who could not converse in either English or French varied by the region of origin, ranging from 11% of Sub‐Saharan Africa population to 47% of Europe and Central Asia. Although, the median years since immigration to Canada varied from 13 to 18 years, a higher percentage of immigrants had no primary care provider compared to Canadian long‐term residents (13.8% vs 7.5%). The proportion of immigrants without a primary care provider was consistently higher among Muslim majority countries compared to non‐Muslim Majority countries across all the region of origins with the exception of immigrants from East Asia and Pacific for whom the proportion was approximately the same . Similarly, the majority of immigrants from Muslim majority countries consulted an internationally trained physician across all the regions of origin with the exception of East Asia and Pacific. Male physicians were more likely to be the primary care providers for immigrants across all regions of origin. The proportion of Muslim and non‐Muslim immigrants across all regions of origin having no health care resource utilization  was approximately four times more than Canadian long‐term residents .Figure Bivariate analyses by region of origin Table  revealedMultivariate analyses Table  show tha4We have shown that Canadian immigrants from Muslim‐majority countries have lower FOBT uptake than those from non‐Muslim majority countries. We have also shown that there is variation in FOBT use between Ontario immigrants from Muslim‐majority countries versus nonmajority countries across all five regions of origin . For instance, people from Muslim‐majority countries in the Middle East and North Africa and Eastern Europe and Central Asia had relatively higher FOBT use than their peers from nonmajority countries. However, FOBT use was similar for majority and nonmajority countries in East Asia, and relatively lower for those from Muslim majority countries in South Asia and Sub‐Saharan Africa. These findings not only substantiate earlier studiesOur findings illustrate religion affiliation as an independent factor in shaping people's uptake of FOBT screening. However, the variation in screening uptake across region of origins further suggests the moderating influence of cultural norms, values and practices. Kleinman (1980)The current Canadian immigration landscape includes migrants from source countries who experience economic, political, or religious conflicts both pre‐ and postmigration. Settlement issues such as shelter, employment, education, language, safety, food, social support, and other basic necessities of life may take priority over preventive health measures such as cancer screening. Decline in social class status through deskilling, underemployment as well as overt and covert racial and religious discrimination have been associated with mental stress and poor health in the immigrant communities.Interestingly, our study also found higher adherence to FOBT among those from low versus high income neighborhoods. This does not substantiate other studies that found a direct association between income and adherence to CRC screening.Our results show an association between FOBT screening uptake and having a female primary care provider and being rostered in a PEM. These findings are consistent with prior research that demonstrated that having a regular primary care provider and certain characteristics of the primary care provider like gender, location of training, number of years in practice‐ promote cancer screening.Finally, although information regarding CRC screening and the importance of early detection is available onlineOur reliance on administrative data imposes several limitations on our findings: First, the use of country of birth as a proxy for religion may present a challenge since being born in a Muslim majority country does not indicate the religion of an individual or their religiosity. However, this was the best proxy available to use since data on religion and ethnicity are not captured in Ontario's health or administrative databases. Second, the IRCC data only contain information on immigrants who landed in Ontario since 1985. Those who landed in other provinces and then relocated to Ontario are not captured in IRCC, and would inadvertently not be included in our study cohort. Third, our study did not include colonoscopy utilization as part of our study outcome. Some of the study participants who were not up to date with FOBT may be up to date with colonoscopy. However, colonoscopy is not the recommended screening option in Ontario for the average‐risk population, and we have been careful to only draw conclusions about FOBT uptake, not CRC screening uptake, from our results. As well, our findings are in line with those of Shen et al5In this population‐based study, we examined factors associated with nonadherence to FOBT screening among immigrants from Muslim majority countries. FOBT uptake was associated with world region of origin, immigration class, rostering in a PEM, providers' sex and training. Although low FOBT screening uptake exists across all the regions, immigrants from the Middle East and North Africa and Eastern Europe and Central Asia countries were the least likely to use FOBT. Attachment to primary care models, having a female primary care provider and having an internationally trained physician were associated with higher FOBT use among immigrants from Muslim majority countries. Our findings have several implications as possible strategies that could improve uptake of FOBT: (a) enhancing immigrants access to regular primary care providers, particularly female providers and enrollment in primary care models; (b) physician‐targeted cancer screening outreach particularly for Canadian trained males and non‐PEM (c) developing culturally sensitive and appropriate educational materials in collaboration with faith organizations and immigration and community‐based organizations to promote knowledge and awareness of immigrants regarding the availability and purpose of CRC screening; and finally 4) using interactive approaches (like face‐to‐face) in communication of CRC screening information among immigrants.The authors declare that they have no competing interests.Lisa Ellison and Erin Graves extracted the data based on specification provided by Mandana Vahabi and Aisha Lofters. Mandana Vahabi processed and analyzed the data and drafted the article; Aisha Lofters, Josephine Wong, Erin Graves, Cynthia Damba, and Richard Glazier reviewed the article critically for intellectual content. All the authors gave final approval of the version to be published and agreed to serve as guarantors of the work.This study falls under Section 45 of Ontario's Personal Health Information Protection Act (PHIPA) which does not require Research Ethics Board Review. Section 45 authorizes health information custodians to disclose personal health information to a prescribed entity, like ICES, without consent.Not Applicable. Click here for additional data file.


The striatum constitutes the cortical‐basal ganglia loop and receives input from the cerebral cortex. Previous MRI studies have parcellated the human striatum using clustering analyses of structural/functional connectivity with the cerebral cortex. However, it is currently unclear how the striatal regions functionally interact with the cerebral cortex to organize cortical functions in the temporal domain. In the present human functional MRI study, the striatum was parcellated using boundary mapping analyses to reveal the fine architecture of the striatum by focusing on local gradient of functional connectivity. Boundary mapping analyses revealed approximately 100 subdivisions of the striatum. Many of the striatal subdivisions were functionally connected with specific combinations of cerebrocortical functional networks, such as somato‐motor (SM) and ventral attention (VA) networks. Time‐resolved functional connectivity analyses further revealed coherent interactions of multiple connectivities between each striatal subdivision and the cerebrocortical networks . These results suggest that the striatum contains a large number of subdivisions that mediate functional coupling between specific combinations of cerebrocortical networks. Written informed consent was obtained from all of the participants according to the Declaration of Helsinki. The experimental procedures were approved by the Institutional Review Board of Juntendo University School of Medicine.Ten right‐handed healthy young participants  (see Table z = 0.39) . Figure The parcellation analysis Figure  revealedn Figure b. In a gn Figure , the boun Figure b. The bon Figure c with a 3.2SD of Fisher's z value of the striatal correlation map within each striatal subdivision  and the average SD within the shifted the subdivisions as a control (red line) in one participant. The distribution of the SDs was significantly lower than the control , which suggests that the cerebrocortical parcels are more likely connected uniformly within the striatal subdivisions.We examined how the striatum was related to the cerebrocortical parcels at the subdivision level by calculating the across‐voxel n Figure a. Figure3.3z = 0.50)  , with negative correlation values in two of the participants  striatal subdivisions Figure c. Althou3.4Previous studies of striatal functional architecture have revealed a well‐organized relationship for cerebrocortical‐striatal connectivity  = 35.2, p < .019].We then examined how the striatal subdivisions were convergently connected with the two cerebrocortical networks. When the second strongest connectivity was less than 30% of the strongest one, the SSC was excluded from the analysis, resulting in exclusion of 21.2% of the total SSCs. Figure It has been demonstrated that the spatial extent of the DM network is variable among individuals , t(9) = 11.6, p < .001] and between SSC‐VA and SSC‐FP , which suggested that temporal changes in the connectivity between SSC‐SM and SSC‐VA and between SSC‐VA and SSC‐FP were temporally coherent.Striatal subdivisions were likely connected with multiple cerebrocortical networks such as the SM‐VA and VA‐FP networks. Figure 3.7We also measured the brain activity when participants performed a standard eye movement task , suggesting that the functional organization of the striatum is rather intricate when viewed at the scale of the striatal subdivisions. At the same time, the larger scale organization of the striatum from the same data (Supporting Information Figure Although the similarity of correlation maps from adjacent striatal subdivisions Figure  was bareThe authors have no conflict of interest to declare.Appendix S1: Supporting InformationClick here for additional data file.


STIs) remain prevalent and are increasing in several populations. Appropriate STI diagnosis is crucial to prevent the transmission and sequelae of untreated infection. We reviewed the diagnostic accuracy of syndromic case management and existing point‐of‐care tests (POCTs), including those in the pipeline, to diagnose STIs in resource‐constrained settings.Sexually transmitted infections  and Neisseria gonorrhoeae (NG) infections limit the use of vaginal discharge and anorectal syndromes. The pooled diagnostic accuracy of vaginal syndromic case management for CT/NG is low, resulting in high numbers of overtreatment and missed treatment. The absolute effect of POCTs was reduced overtreatment and missed treatment. Findings of the reviews on syndromic case management underscored the need for low‐cost and accurate POCTs for the identification, first, of CT/NG, and, second, of Mycoplasma genitalium (MG) and Trichomonas vaginalis (TV) and NG and MG resistance/susceptibility testing. Near‐patient POCT molecular assays for CT/NG/TV are commercially available. The prices of these POCTs remain the barrier for uptake in resource‐constrained settings. This is driving the development of lower cost solutions.The diagnostic accuracy of urethral discharge and genital ulcer disease syndromes is relatively adequate. Asymptomatic WHO syndromic case management guidelines should be updated to raise the quality of STI management through the integration of laboratory tests. STI screening strategies are needed to address asymptomatic STIs. POCTs that are accurate, rapid, simple and affordable are urgently needed in resource‐constrained settings to support the uptake of aetiological diagnosis and treatment.The  AMRAntimicrobial resistanceBVbacterial vaginosisCTChlamydia trachomatisFDAFood and Drug AdministrationGUDgenital ulcer diseaseHCPhealth care providerHIVhuman immunodeficiency virusHSVherpes simplex virusICTimmunochromatographic testsLFAlateral flow assaysLMICslow‐ and middle‐income countriesMGMycoplasma genitaliumMSMmen who have sex with menNAATnucleic acid amplification testsNGNeisseria gonorrhoeaeOIAoptimal immunoassayPCRpolymerase chain reactionPIDpelvic inflammatory diseasePOCTpoint‐of‐care testRDTrapid diagnostic testRPRrapid plasma reaginSDGSustainable Development GoalSRHsexual and reproductive healthSTIsexually transmitted infectionTPTreponemaTPHATreponema pallidum haemagglutinationTVTrichomonas vaginalisWHOWorld Health Organization1Sexually transmitted infections (STIs) remain prevalent and a major burden of morbidity and mortality globally The global STI strategy, endorsed by the World Health Assembly in 2016 aims to end STIs as a public health threat by 2030 Thus, appropriate STI diagnosis and treatment is crucial to prevent the transmission and sequelae of untreated infection To overcome limited access to aetiological diagnosis and treatment, syndromic case management was introduced by the World Health Organization (WHO) in 1984 and continues to be used as the standard of care by many countries, especially resource‐constrained ones Chlamydia trachomatis (CT) and/or Neisseria gonorrhoeae (NG) Mycoplasma genitalium (MG) with limited treatment options make it imperative that treatments are based on aetiological diagnosis Syndromic management has been successful in reducing the prevalence of STIs over the years, such as chancroid and the incidence of male urethritis Point‐of‐care tests (POCTs) in accordance with the ASSURED criteria  are essential to address these challenges This paper reviews the diagnostic accuracy of syndromic case management, and the existing POCTs and those in the pipeline to detect STIs that could potentially be used in resource‐constrained settings.2Candida albicans, motile trichomonads for Trichomonas vaginalis (TV) and Amsel criteria for diagnosis of bacterial vaginosis (BV); and flowchart 4 = country‐adapted flowcharts with country‐specific risk factors or those not defined by the study methods. Four additional studies were added to the meta‐analysis Because of the challenges in diagnosing STIs in women, we prioritized updating the systematic review of studies from January 2001 to March 2015 and the meta‐analysis of the diagnostic accuracy of vaginal discharge by Zemouri et al. Based on the diagnostic accuracy for CT/NG of different vaginal discharge flowcharts, we calculated absolute effects on important outcomes – true positive, false positive (resulting in overtreatment), true negative and false negative (resulting in incorrect or missed treatment) in different CT/NG prevalence settings 5%, 15%, 30%). We then calculated the absolute effects on the important outcomes in different CT/NG prevalence settings using rapid diagnostic tests (RDTs) with sensitivities of 60%, 70% and 80%, and specificity of 90%, to represent the ranges of sensitivity and the lowest acceptable specificity of the RDTs detailed in Table %. We theWe searched the peer‐reviewed literature for previous systematic reviews, randomized controlled trials and non‐randomized studies from 2000 to 2018 on the diagnostic accuracy of syndromic management for vaginal and urethral discharge, genital ulcer and anorectal infections. We selected studies from searches of the PubMed and Medline databases. We chose articles that appropriately addressed the key issues and we did not apply eligibility criteria to include or exclude articles.We conducted literature reviews on existing POCTs and those in the pipeline, on patient and healthcare provider (HCP) values and preferences, and on the costs and cost‐effectiveness of POCTs for STIs. We searched PubMed and Medline databases from 2000 to 2018. We used the search terms point of care, POC, POCT, rapid test, laboratory tests, laboratory diagnosis, aetiologic diagnosis and sexually transmitted infections/diseases. We searched reviews, editorials and systematic reviews for additional publications.33.1Syndromic management for urethral discharge in men had sensitivities ranging from 84% to 95%. Treatment based on this syndrome is simple, inexpensive and cost‐effective Genital HSV infection is the predominant cause of GUD that affects the outcome of syndromic management of GUD The WHO simplified generic tool includes flowcharts for women with symptoms of vaginal discharge and/or lower abdominal pain. While the flowcharts for abdominal pain are relatively satisfactory A review by Sloan et al. also revealed that syndromic management had low diagnostic accuracy for screening and case‐finding of CT/NG in women Based on our update of the systematic review and meta‐analysis by Zemouri et al. The pooled sensitivity and specificity of the various flowcharts to diagnose cervical infection due to CT/NG are summarized in Table The absolute effect of different prevalence using the pooled sensitivities and specificities of the different vaginal discharge flowcharts reveal that the low diagnostic accuracy of vaginal syndromic case management results in high numbers of false positives (lower specificity), leading to overtreatment, and high numbers of false negatives (lower sensitivity), resulting in incorrect and missed treatment Table . The absThe flowchart for syndromic management of anorectal infections intends to treat CT/NG rather than being solely based on symptoms and signs Unprotected anal sex is the entry point to the flowchart for anorectal infections. While it is recommended that carefully worded questions can be used to elicit anal sex in sub‐Saharan Africa 3.2Nucleic acid amplification tests (NAATs) are the gold standard for the diagnosis of STIs in high‐income settings, and most have a sensitivity and specificity ranging from 95% to 99% 3.33.3.1Syphilis prevalence is increasing in many countries Treponema pallidum haemagglutination (TPHA) and Treponema pallidum particle agglutination tests There are several syphilis RDTs – rapid POCTs, that is – for screening . Most of these tests use whole blood, plasma or serum and can be performed between five and thirty minutes. Based on a meta‐analysis by Jafari et al., sensitivity ranges from 75% to 99% and specificity from 92% to 99% compared with p < 0.0001) and the non‐TP component . Overall agreement with TPHA was 85.2% (84.4% to 86.1%). Agreement was highest for high‐titre active infection, and lowest for past infection The main challenge with most syphilis RDTs, detecting only “specific” treponemal (TP) antibodies, is the inability to differentiate active from previously treated infection. To reduce overtreatment, especially in high‐prevalence populations (>5%), an initial RDT is performed and, if positive, this is followed by a rapid plasma reagin (RPR) test, which detects non‐TP antibodies, indicating an active infection. If the RPR test is reactive, treatment for syphilis is provided HIV testing has been scaled up in most countries, while syphilis screening lags behind. Implementing a combination test of HIV and syphilis will increase syphilis screening coverage, contributing to eliminating mother‐to‐child transmission of HIV and syphilis 3.3.2CT infection remains the most prevalent bacterial STI CT antigen detection POCTs are available. As described in a recent systematic review by Kelly et al. There have been fewer POCTs developed for gonorrhoea, and many have been validated only by the manufacturer and are not currently commercially available. The diagnostic sensitivities of these tests are generally lower than of the CT LFAs/ICTs Table .The performance of some NG POCTs was evaluated only against culture, and not the more accurate NAATs (gold‐standard test), and only symptomatic patients were included in the evaluation. No gonorrhoea POCT has been evaluated for extragenital sites. Rapid POCTs  take five to seven steps, but have turnaround times of only 25 to 40 minutes, making them suitable for primary care settings The near‐patient Xpert CT/NG  on the GeneXpert instruments is approved by the United States Food and Drug Administration (FDA). The diagnostic accuracy from self‐collected vaginal swabs, cervical swabs and urine range from 95% to 98%, with specificities ranging from 99.4% to 99.9%. The sensitivity and specificity of this assay for rectal swabs are 86.0% and 99.2% respectively The Xpert CT/NG takes three steps and 90 minutes, and requires equipment (GeneXpert), steady electricity, calibration, a temperature‐controlled environment Several platforms and assays are being developed to be more portable, easier to operate, used at the point of care and giving rapid turnaround times for results, with accuracy similar to that of laboratory‐based NAATs, such as the GeneXpert Omni, Alere – i platform, RT CPA CT Test, Atlas Genetics io Platform POCTs that are inexpensive, rapid and fulfil the ASSURED criteria are under development. These molecular assays include: the microwave‐accelerated metal‐enhanced fluorescence test, which needs to be simplified and standardized for basic laboratories Some companies are working on antigen‐ or protein‐based detection of AMR in NG (i.e. LFA‐type tests). However, this is very early work, and development and commercial pathways are unclear, as are timelines. There are several well‐characterized molecular AMR determinants that can be used for effective prediction of AMR in NG, particularly for ciprofloxacin, but less adequate prediction of resistance to azithromycin, cefixime and ceftriaxone 3.3.3TV is the most prevalent curable STI globally and is a major cause of vaginal discharge as well as recurrent urethral discharge in men 3.3.4Qualitative studies conducted by Hsieh et al. HCPs have expressed confidence in the POCT NAAT results, and treating patients on this basis 4The provision of effective services to symptomatic and ideally also asymptomatic STI patients and their partners should be among the top priorities of an STI control programme. Symptomatic STI patients may be aware that they are infected and are more likely to seek care. Thus, syndromic management provides an entry point for STI management and control. However, there are clearly limitations to the syndromic approach for the management of STIs, the likely impact on the control of STIs and the link with AMR While urethral discharge has relatively adequate diagnostic accuracy, treatment has been limited to CT/NG. It is also critical to address asymptomatic CT/NG and to assess the aetiologies of persistent urethral discharge, including MG and TV, as well as the treatment failures due to AMR in NG and MG.Previous syndromic management has not considered MG as an important aetiological agent of urethral and vaginal discharge and pelvic inflammatory disease (PID). MG frequently causes non‐gonococcal urethritis (NGU) and non‐chlamydial‐NGU in men and is associated with vaginal discharge and PID in women Most NG, and especially CT and MG, cervical infections in women are subclinical or asymptomatic so there would be no syndromic presentation Based on the available evidence, vaginal discharge syndrome has adequate diagnostic accuracy to detect vaginal infections (TV and BV) Table , but hasPatients with vaginal and urethral discharge syndromes are mostly seen in primary care settings, which do not have accessible diagnostics to confirm either CT/NG/MG/TV. Although one FDA‐approved near‐patient (POCT) molecular assay (Xpert CT/NG) is available to distinguish between CT and NG, the cost and other limitations The severity of symptoms associated with various STI pathogens and the anatomical sites infected greatly influence treatment‐seeking behaviour AMR to the first‐line NG treatment regimen of ceftriaxone plus azithromycin, and AMR in MG to azithromycin (first‐line) and moxifloxacin (second‐line), has now been reported This review highlights the need to integrate currently available laboratory‐based diagnostics and POCTs within syndromic case management to decrease overtreatment and missed treatment as well as to contribute to the conservation of NG treatment. A recent study by Verwijs et al. Laboratory diagnostics will also be essential for implementing STI screening strategies. The unit cost per test can be higher compared with treatment costs, which often remains the major concern of national programmes in investing in laboratory diagnosis. However, the cost savings obtained from the rapid delivery of results, reduction of patient follow‐up, facility cost, decreased complications and onward transmission are often overlooked A cost‐effectiveness analysis has shown that a NG NAAT screening of women between 15 and 29 years of age can prevent 1247 cases of PID and save US$177 per patient compared with no screening, while using a potential POCT with about 75% sensitivity can prevent additional PID Supplementing the laboratory‐based NAATs for CT/NG with POCTs NAAT could be cost‐saving and patients could benefit from accurate diagnosis, and immediate and appropriate treatment. POCTs can reduce overtreatment and eliminate the need for presumptive treatment Modelling the impact of a rapid testing service showed that it could reduce the mean time to treatment notification from eight days to less than a day, and avert more CT/NG transmission. Additionally, there is an annual saving in the number of partner attendances POCT with AMR detection has shown that there is an additional cost for this POCT, but its use could reduce the cost from follow‐up visits and could allow for the use of older and cheaper drugs, such as ciprofloxacin and, more importantly, conserve the current last‐resort options of ceftriaxone and azithromycin Test cost is a significant factor in the use of available NAATs and the development and utility of POCTs. Although cost‐effective, the unit cost per test of a NAATs ranges from US$14 to US$30 per sample, which is often unaffordable in resource‐constrained settings The potential use of molecular diagnostic assays in resource‐constrained settings is driving the development of lower‐cost solutions. Several new industry players have entered, or are entering the development space; however, these tests, previously mentioned The development of POCTs will need to ensure access and uptake at the primary health care level. Self‐sampling  has shown to increase POCT use and is thus an important consideration in POCT development 5In the present review, the available evidence on the effectiveness and challenges of syndromic case management further underscores the need to scale up existing STI diagnostics and the development of POCTs for, first, the identification of CT/NG, but ideally also MG and TV, as well as NG and MG AMR in vaginal, urethral and anorectal discharge.One of the biggest challenges in STI control is that most cases are asymptomatic or have unrecognized symptoms Although near‐patient NAAT for CT/NG/TV is commercially available, the cost and other limitations remain prohibitive for use, particularly but not exclusively in resource‐constrained settings POCTs that are simple and affordable are essential in STI control and are urgently needed in resource‐constrained settings. The development and implementation of POCTs will require innovative financing approaches and implementation strategies, and the strengthening of laboratory capacity. Although several POCTs for CT/NG are in the pipeline, the development of affordable POCTs will take several more years. Syndromic management of symptomatic STIs will remain essential in resource‐constrained settings. At the interim, guidelines should be updated to improve the standard of care and to explore the utility of available POCTs and near‐patient NAATs to improve STI diagnosis and screening. Laboratory and clinical validation studies and cost‐effectiveness analyses of integrating POCTs into current syndromic case management, and of screening strategies, are urgently needed to inform guidelines and national policies.The limitation of the syndromic approach, the availability of molecular assays and the ongoing development of POCTs call for global action to increase the access and affordability of the aetiologically based diagnosis of STIs in resource‐constrained settings to improve patient management, and reduce STI transmission and the emergence of drug resistance. Finally, global initiatives are needed to make current near‐patient NAATs more affordable through subsidized cost and bulk procurement.The authors declare no conflicts of interest.TW drafted the review and all authors contributed. All authors contributed in the final review of the manuscript. NS designed and conducted the search and data extraction for the vaginal discharge syndrome systematic review and meta‐analysis.Data S1. Updated systematic review of vaginal discharge.Figure S1. PRISMA flow diagramClick here for additional data file.


Loss‐of‐function experiments in animal and cellular models indicate that both STIM1 and STIM2 regulate neutrophil functions, but the complexity of the SOCE machinery and the versatility of neutrophils complicate the evaluation of the results. This review aims to summarize the latest progress in the field, with special attention to the details of the experimental designs. Future study design should aim to improve the standardization of experimental procedures and to provide a more holistic understanding of the role of STIM proteins in neutrophils function.Stromal interaction molecule (STIM) proteins regulate store‐operated Ca The SOCE pathway mediated by STIM1‐ORAI1 interactions was then shown to be essential for T lymphocyte activation and proliferation and to regulate neutrophil functions  following the engagement of plasma‐membrane receptors. InsP3 binds and opens its cognate receptors in the endoplasmic reticulum (ER), triggering a Ca2+ release from intracellular stores. The drop in ER‐luminal Ca2+ concentration leads to dissociation of Ca2+ from EF‐hands of STIM1 and STIM2 proteins residing in the ER membrane. Subsequently, STIM proteins undergo a conformational change and translocate to ER‐plasma‐membrane contact sites. Here they trap and gate Ca2+‐permeable channels of the ORAI and TRP families, of which several isoforms exist, enabling a sustained influx of Ca2+ into the cytosol.Within the last decade, significant progress has been made in understanding the SOCE machinery, and the dynamic STIM‐ORAI interactions have been clarified at the cellular and molecular level  of bacterial‐derived fMLF activating STIM2, and high doses preferentially activating STIM1  was not altered by STIM1 ablation in their psoriasis model. Only Clemens and colleagues, in the most comprehensive analysis so far, investigated cytokine synthesis, production and release, and also considered a role of STIM2 in this crucial process.Whether specific neutrophil functions are predominantly regulated by STIM1 or STIM2 is still not firmly established, since only a few studies have analysed the function of the two proteins in parallel. As summarized by Nunes and Demaurex , a S. aureus‐induced pneumonitis , and an immune complex (IC)‐induced pneumonitis , using a Mrp8‐Cre‐lox  cell‐dependent pathogen clearance ‐induced peritonitis  and an IC‐induced pneumonitis  in a fetal liver chimeric model. The different disease models revealed opposite effects of STIM1 ablation, with neutrophil recruitment being increased in the peritoneal cavity and decreased in the lung  , FcyRs or TLRs. Although the range of receptors is limited, the downstream signalling cascades activated are multiple and difficult to predict, involving different adapter proteins for TLRs, phospholipases (PLC) for GPCRs and FcyRs, and different kinases  for FcyRs, TLRs and GPCRs. How STIM1‐ and STIM2‐mediated SOCE differentially triggers these, and potentially other, signalling pathways in neutrophils, thereby engaging the activation of specific functions or transcription factors, is still unclear. Clemens et al. demonstrated that specific targets can be identified, but the molecular details of the underlying cellular signalling circuit remain to be clarified. Without a detailed analysis of the downstream components that are activated, it is difficult to associate the observed effects of STIM ablation to specific molecular targets. Further studies are required to understand how separate or simultaneous activation of STIM1 and STIM2 can activate specific signalling cascades.A detailed analysis of downstream targets is crucial to reveal pathways specifically controlled by STIM1 and STIM2 and to clarify their redundancies or synergies, as recently shown by Clemens and colleagues. Most in vitro and in vivo. Standardization procedures aiming to minimize system‐ and design‐related differences should be adopted to clarify the role of STIM1 and STIM2 proteins, not only in chemotaxis but also other neutrophil functions.Taken together, the described differences in experimental design call for future replication studies that should cover a broad range of stimuli targeting different sub‐cellular pathways and use comparable experimental set‐ups The excellent work of several groups has provided significant insight into the regulation of SOCE‐dependent functions by STIM proteins in neutrophils. Nonetheless, there is a strong need for replication studies to confirm the dominant role of STIM1 in ROS production, to clarify diverging reports linking STIM1 to impaired or enhanced chemotaxis and neutrophil recruitment and to elucidate the involvement of the two isoforms in degranulation and cytokine secretion. An important and overlooked aspect will be to improve the standardization of experimental procedures to allow proper comparison of future studies. Due to the specific focus of this short review we were not able to include all publications concerning the role of SOCE in neutrophil function and would like to apologize to those colleagues whose work we could not include.The authors declare no competing financial interests.N.D. and S.S. outlined and wrote the review. N.D. edited the final version of the manuscript. S.S. designed the figures. Both authors accept the final version of the manuscript as submitted.This work was funded by grant 31003A‐149566 and CRSII3_ 160782 of the Swiss national science foundation (SNF) awarded to N.D.


To the Editor:We thank Massart et al for their commentsCCDC67) and rs7976329 (gene annotation PTPRO), were well imputed in our study (INFO>0.95) and neither reached genome‐wide significance in our reported analyses.The 2 recipient genetic loci highlighted in their paper,Table The lack of replication signal in our study, despite greater numbers of cases, may be due to a number of factors. We agree with Massart et al that one reason may be the differences in phenotype definition. Our study was primarily designed and powered to detect genetic variation in donor and recipient genomes associated with long‐term graft survival, as this is the key unmet medical need in clinical renal transplantation outcomes, with currently no effective therapeutic options. Our acute rejection phenotype was established from reported national registry‐based outcomes and was not specific to acute T cell–mediated rejection, and thus signal attenuation may be responsible for the difference. However, we note that in our study the recipient minor allele frequency differences between cases and controls are less than 1%, indicating almost complete attenuation. Alternatively, it is possible that the signals found by Ghisdal et alWe agree that genetic variation outside the HLA region is an important consideration in seeking to understand the pathogenesis of long‐term graft survival and potentially identifying novel therapeutic targets to reduce cumulative allograft loss over time. We look forward to working with already established international collaborationsAmerican Journal of Transplantation.The authors of this manuscript have no conflicts of interest to disclose as described by the


Finally, we discuss the unique features that distinguish iNs from other reprogramming‐based neuronal cell models and how iNs are relevant to disease modeling.Within just over a decade, human reprogramming‐based disease modeling has developed from a rather outlandish idea into an essential part of disease research. While iPSCs are a valuable tool for modeling developmental and monogenetic disorders, their rejuvenated identity poses limitations for modeling age‐associated diseases. Direct cell‐type conversion of fibroblasts into induced neurons (iNs) circumvents rejuvenation and preserves hallmarks of cellular aging. iNs are thus advantageous for modeling diseases that possess strong age‐related and epigenetic contributions and can complement iPSC‐based strategies for disease modeling. In this review, we provide an overview of the state of the art of direct iN conversion and describe the key epigenetic, transcriptomic, and metabolic changes that occur in converting fibroblasts. Furthermore, we summarize new insights into this fascinating process, particularly focusing on the rapidly changing criteria used to define and characterize   ALS, amyotrophic lateral sclerosisHD, Huntington’s diseaseiNs, induced neuronsiPSCs, induced pluripotent stem cellsTF, transcription factorin vivo and in vitro, have provided eye‐opening insights into the inner workings of neurons and the brain. Animal models of brain disorders have however been found to not necessarily reflect complex human conditions and have unfortunately not been very predictive for the evaluation of drug candidates for several diseases. Alzheimer’s disease stands out as a prime example to illustrate this puzzle. Animals, typically mice, can be genetically engineered to reflect central pathological hallmarks of the human disease, but all drug candidates that were developed based on successful animal studies have failed in clinical trials in vitro can help to capture and better understand disease‐related factors that require a human neuronal cell physiology, human genetics, epigenetic signatures, and age, the generation of human neurons as disease models has received broad attention as a potential game‐changer.The immense processing power of the human brain is enabled by unique features of the brain’s hardware: around 86 billion neurons with each one of them possessing thousands of synaptic connections Notably, the direct conversion from one cell type into another, often also called fate conversion, direct reprogramming, or transdifferentiation, has been first demonstrated already in the 1980s, where it was shown that overexpression of the transcription factor (TF) MyoD can convert fibroblasts into myoblast‐like cells Unlike neural differentiation protocols starting from iPSCs, direct iN conversion does not follow the concerted chronological stages of development, as one cell type is rather directly transformed into another one While pioneer TFs are sufficient for iN conversion, they are not essential and several laboratories have successfully obtained iNs without exploiting the classical pioneer TFs Table . Those sAmong the growing number of successful iN‐conversion protocols, two main strategies have crystalized that facilitate increased conversion efficiencies and more authentic neuronal outcomes: (a) co‐overexpression of pioneer TFs with boosting TFs, and (b) combination of pioneer TFs with media containing cocktails of signaling‐pathway modulators Fig. C.The first published direct conversion strategy was based on an overexpression of the three TFs, namely Ascl1, Brn2, and Myt1l (BAM factors), in mouse fibroblasts Besides TFs, miRNAs have also been harnessed as iN boosters, and REST inhibition or overexpression of REST‐associated miRNAs could highly enhance conversion of adult and diseased fibroblasts in pioneer TF‐based settings TP53, serum withdrawal, CDK2 and mTOR inhibition, and chemical JAK/STAT inhibition, which further helps iN conversion by inhibiting both epithelial‐to‐mesenchymal transition and apoptosis Both purified and recombinant proteins and chemical compounds have been identified to enhance iN generation and have further been helpful to better understand the mechanisms of direct iN conversion Fig. C. Solublin vivo resemble mixed GABAergic/glutamatergic cultures in vitro with patient‐specific cells, astrocytes and oligodendrocytes are currently generated via direct conversion from human iPSCs, but direct conversion protocols from fibroblasts into induced astrocytes and oligodendrocytes have yet only been established for rodent cells et al.]. Further, peripheral Schwann cells are of great interest for the study and treatment of spinal cord injuries and have been generated from adult human fibroblasts, representing exciting new possibilities for peripheral nerve regeneration in vitro. The next important steps in the near future would be the development of protocols for the generation of induced glial cell types also from human somatic cells and extension of existing protocols to other, more accessible starting populations, such as human peripheral blood cells In the developing brain, as well as in iPSC differentiation, differentiating neural cells pass through a series of well‐defined developmental neural precursor stages, some of which are amenable to regionalizing patterning signals to specify specific neuronal subtypes in vivo at any given time, but rejects cellular chimeras, which would be cells that transiently share neuronal and starting cell properties, and which are rarely described The famous epigenetic landscape model established by Waddington is an outstanding model to describe cell fate switches during normal development and iPSC differentiation To explore the differences between the transcriptome path and outcome of stem cell differentiation and direct iN conversion, an elegant study employed single‐cell transcriptome analysis of neurons generated through neural stem cell differentiation and direct conversion of neural stem cells into iNs Developmental and differentiation protocols are expected to roughly follow similar epigenetic sequences. Starting from somewhere between the zygote and blastocyst stages in development or from embryonic stem cells or iPSCs in differentiation protocols, modifications to the epigenetic landscape follow a hierarchical and highly orchestrated sequence of events that ultimately lead to a differentiated cell In fibroblast‐to‐iN conversion, Ascl1 exerts its function already a few hours after induction, acting as a transcriptional activator inducing neuronal‐ and muscle‐related gene expression Originally regarded more as a mere characteristic of neurons, a growing body of evidence now suggests a central role for metabolic regulation in differentiation and direct iN conversion real neuron…’. Since the first neurons were generated from human embryonic stem cells, an evergreen question has been if obtained cells should be called neurons, or if they should rather be described as neuronal‐like cells. While some argue that human stem cell‐derived neurons should be called a neuron once they meet a set of electrophysiological characteristics, others suggest to rather call them neuronal‐like cells to avoid confusion with primary neurons in vivo‐born cells, recent work has demonstrated that the environment of cells appears to be more important for cellular identity than the origin of cells, indicating that cell identity is plastic and highly environment‐dependent ‘Well well well, so you want to be a 2+ imaging and multielectrode arrays can be used as surrogates for electrophysiology and can further deliver insights into neuronal network activity in vitroWith the establishment of (epi)genomic sequencing and epigenetic array technologies, single‐cell technologies, and new insights into the complexity of neurological diseases, the historic neuron‐electrophysiology‐centric view on neuronal identity, function, and disease is fading et al. in vitro models, which has detected marked differences between laboratories and differentiation protocols. Nayler et al. in vivo data and found that the cells recapitulate gene expression trajectories that correspond specifically to human fetal neocortical development. This concept was later extended toward new insights into cellular diversity, once also in vivo single‐cell data of the developing human brain became available et al. While classical cell biological and electrophysiological criteria are a gold standard for characterizing such cells in culture, and transplantation experiments have a strong relevance and broad implications, they do not tell us much about more general measures that define cell identity. Neurons do not only have unique electrical properties, but also have unique epigenetic, proteomic, metabolic, and other characteristics that might be equally important for the roles they play in the brain. While marker expression and electrophysiological characteristics often correlate with cell identity, they are considered to be downstream of epigenetic and proteomic changes and likely follow earlier pathogenic events in neurological diseases. Immunocytochemical data are further quite variable between experiments, antibody batches, and laboratories, thus not well‐quantifiable, low‐dimensional, and thus less ideal to be directly compared by statistically powerful (meta‐)analytical means. Conversely, gene expression changes related to synapse formation, voltage‐gated potassium channels, or mitochondrial oxidative phosphorylation critically define mature neuronal identity et al. have employed this tool to demonstrate for the first time that iNs from adult donors are indeed  adult cells, while iPSCs and their derivatives are typically rejuvenated into prenatal epigenetic ages et al. recently showed that in contrast to iPSC‐derived neurons, BAM‐based iNs are the first cellular neuronal model system displaying this epigenetic hallmark of mature adult neurons Further, biological or epigenetic age can be well measured using the DNA methylation profile exploiting a growing number of epigenetic clock algorithms In vitro generation of patient‐specific neurons from iPSCs for modeling diseases of the brain has evolved into an integral part of neuroscience It is primarily due to the inaccessibility of live human brain tissue that most studies on complex age‐related neurodegenerative disorders have primarily relied on transgenic animal models that, while yielding important insights, have also revealed limitations regarding transferability to human physiology. et al. et al. Importantly, the rejuvenating effect of iPSC reprogramming should mostly be regarded as an additional advantage, because comparing phenotypically young and phenotypically old neurons from the same donor (isogenic rejuvenated control) can help to reduce donor‐specific bias and allows assessing the contribution of age to the disease phenotype. Although it is a new concept, harnessing the power of combining iPSC differentiation and direct iN conversion has already been published. Tang et al. have used iPSC differentiation and iN conversion starting from iPSCs in parallel, and only iPSC differentiation revealed a disease‐related phenotype, while iN conversion did not. Specifically, the study explored developmental transcriptomic and epigenomic trajectories in autism spectrum disorder using classical neural differentiation and cerebral organoids. As opposed to the most widely believed assumption that the first disease phenotypes emerge in immature neurons, they found heterochronic trajectories in patient cells that were already epigenetically primed for acceleration at the neural stem cell stage While most studies imply that iN conversion is particularly useful for modeling age‐associated diseases, direct reprogramming approach is not always the method of choice for disease modeling, especially not when it comes to developmental diseases such as autism spectrum disorder. Schafer in vitro disease modeling in the future. For example, iPSC derivatives have been shown to resemble fetal stages of brain development, and it remains an open question to what extent iNs from fetal, neonatal, and adult donor fibroblasts would resemble neurons of the according developmental stages. These questions must be addressed with state‐of‐the‐art tools for defining and comparing cell identities. A fetal identity of neurons after iPSC differentiation, however, does not implicate a functionally immature cellular phenotype, as both directly converted neurons and iPSC‐derived neurons can show mature neuronal markers and features There are probably more meaningful conceptual differences between iN‐based and iPSC‐derived models that only wait to be explored and that have the potential to significantly improve Additionally, iNs exhibit various technical advantages as well as critical disadvantages compared to iPSC reprogramming, which have been discussed more in detail elsewhere in vivo cell replacement therapies. Unlike iPSC‐based differentiation to neurons, iNs circumvent the known paths of neurodevelopment, and we have started to better understand the mechanics of this process in the recent years. The unique characteristics of iNs already let them stand out as a valuable tool for many applications. Among the best‐known phenomena is the age‐preserving characteristic of iNs, which makes them a useful complement to iPSC models of brain aging and age‐related diseases. Today is only the dawn of this technology, and the development of more direct conversion protocols and applications can be expected in the near future. Application of iN technology profits from the rapid developments in the iPSC field, and iNs already leave their mark in the current process of redefining how we think about cell fate, neuronal identity, and possibilities to deconstruct and reconstruct the inner workings of the human brain.Direct iN conversion offers a valuable addition to iPSCs to study the fundamentals of cell identity, investigate human neuronal function, and model neurological diseases, and as a new strategy for