One-Year Recovery Among Survivors of Prolonged Severe COVID-19: A National Multicenter Cohort.

OBJECTIVES: Understanding the long-term effects of severe COVID-19 illness on survivors is essential for effective pandemic recovery planning. Therefore, we investigated impairments among hospitalized adults discharged to long-term acute care hospitals (LTACHs) for prolonged severe COVID-19 illness who survived 1 year. DESIGN: The Recovery After Transfer to an LTACH for COVID-19 (RAFT COVID) study was a national, multicenter, prospective longitudinal cohort study. SETTING AND PATIENTS: We included hospitalized English-speaking adults transferred to one of nine LTACHs in the United States between March 2020 and February 2021 and completed a survey. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Validated instruments for impairments and free response questions about recovering. Among 282 potentially eligible participants who provided permission to be contacted, 156 (55.3%) participated (median age, 65; 38.5% female; 61.3% in good prior health; median length of stay of 57 d; 77% mechanically ventilated for a median of 26 d; 42% had a tracheostomy). Approximately two-thirds (64%) had a persistent impairment, including physical (57%), respiratory (49%; 19% on supplemental oxygen), psychiatric (24%), and cognitive impairments (15%). Nearly half (47%) had two or more impairment types. Participants also experienced persistent debility from hospital-acquired complications, including mononeuropathies and pressure ulcers. Participants described protracted recovery, attributing improvements to exercise/rehabilitation, support, and time. While considered life-altering with 78.7% not returning to their usual health, participants expressed gratitude for recovering; 99% returned home and 60% of previously employed individuals returned to work. CONCLUSIONS: Nearly two-thirds of survivors of among the most prolonged severe COVID-19 illness had persistent impairments at 1 year that resembled post-intensive care syndrome after critical illness plus debility from hospital-acquired complications.

Supporting and Incentivizing Peer Leaders for an Internet-Based Private Peer Community for Youths With Type 1 Diabetes: Social Network and Directed Content Analysis.

BACKGROUND: Youths with type 1 diabetes (T1D) frequently experience stigma. Internet-based peer communities can mitigate this through social support but require leaders to catalyze exchange. Whether nurturing potential leaders translates into a central role has not been well studied. Another issue understudied in such communities is lurking, the viewing of exchanges without commenting or posting. OBJECTIVE: We aimed to assess the centrality of the peer leaders we selected, trained, and incentivized within the Canadian Virtual Peer Network (VPN)-T1D. This is a private Facebook (Meta Platforms, Inc) group that we created for persons aged 14 to 24 years with T1D. We specifically sought to (1) compare a quantitative estimate of network centrality between peer leaders and regular members, (2) assess the proportions of network exchanges that were social support oriented, and (3) assess proportions of high engagement (posts, comments, reactions, and votes) and low engagement (lurking) exchanges. METHODS: We recruited peer leaders and members with T1D from prior study cohorts and clinics. We trained 10 leaders, provided them with a monthly stipend, and encouraged them to post on the private Facebook group we launched on June 21, 2017. We extracted all communications (posts, messages, reactions, polls, votes, and views) that occurred until March 20, 2020. We calculated each member's centrality (80% of higher engagement communications comprising posts, comments, and reactions plus 20% of members with whom they connected). We divided each member's centrality by the highest centrality to compute the relative centrality, and compared the mean values between leaders and members (linear regression). We calculated the proportions of communications that were posts, comments, reactions, and views without reaction. We performed content analysis with a social support framework (informational, emotional, esteem-related, network, and tangible support), applying a maximum of 3 codes per communication. RESULTS: VPN-T1D gained 212 regular members and 10 peer leaders over 33 months; of these 222 members, 26 (11.7%) exited. Peer leaders had 10-fold higher relative centrality than regular members (mean 0.53, SD 0.26 vs mean 0.04, SD 0.05; 0.49 difference; 95% CI 0.44-0.53). Overall, 91.4% (203/222) of the members connected at least once through posts, comments, or reactions. Among the 75,051 communications, there were 5109 (6.81%) posts, comments, and polls, 6233 (8.31%) reactions, and 63,709 (84.9%) views (lurking). Moreover, 54.9% (3430/6253) of codes applied were social support related, 66.4% (2277/3430) of which were informational (eg, insurance and travel preparation), and 20.4% (699/3430) of which were esteem related (eg, relieving blame). CONCLUSIONS: Designating, training, and incentivizing peer leaders may stimulate content exchange and creation. Social support was a key VPN-T1D deliverable. Although lurking accounted for a high proportion of the overall activity, even those demonstrating this type of passive participation likely derived benefits, given that the network exit rate was low. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.2196/18714.

Longitudinal study of 2 patients with cyclic thrombocytopenia, STAT3 and MPL mutations.

Cyclic thrombocytopenia (CTP) is a rare disease of periodic platelet count oscillations. The pathogenesis of CTP remains elusive. To study the underlying pathophysiology and genetic and cellular associations with CTP, we applied systems biology approaches to 2 patients with stable platelet cycling and reciprocal thrombopoietin (TPO) cycling at multiple time points through 2 cycles. Blood transcriptome analysis revealed cycling of platelet-specific genes, which are in parallel with and precede platelet count oscillation, indicating that cyclical platelet production leads platelet count cycling in both patients. Additionally, neutrophil and erythrocyte-specific genes also showed fluctuations correlating with platelet count changes, consistent with TPO effects on hematopoietic progenitors. Moreover, we found novel genetic associations with CTP. One patient had a novel germline heterozygous loss-of-function (LOF) thrombopoietin receptor (MPL) c.1210G>A mutation, and both had pathogenic somatic gain-of-function (GOF) variants in signal transducer and activator of transcription 3 (STAT3). In addition, both patients had clonal T-cell populations that remained stable throughout platelet count cycles. These mutations and clonal T cells may potentially involve in the pathogenic baseline in these patients, rendering exaggerated persistent thrombopoiesis oscillations of their intrinsic rhythm upon homeostatic perturbations. This work provides new insights into the pathophysiology of CTP and possible therapies.

Lymph node colonization induces tumor-immune tolerance to promote distant metastasis.

For many solid malignancies, lymph node (LN) involvement represents a harbinger of distant metastatic disease and, therefore, an important prognostic factor. Beyond its utility as a biomarker, whether and how LN metastasis plays an active role in shaping distant metastasis remains an open question. Here, we develop a syngeneic melanoma mouse model of LN metastasis to investigate how tumors spread to LNs and whether LN colonization influences metastasis to distant tissues. We show that an epigenetically instilled tumor-intrinsic interferon response program confers enhanced LN metastatic potential by enabling the evasion of NK cells and promoting LN colonization. LN metastases resist T cell-mediated cytotoxicity, induce antigen-specific regulatory T cells, and generate tumor-specific immune tolerance that subsequently facilitates distant tumor colonization. These effects extend to human cancers and other murine cancer models, implicating a conserved systemic mechanism by which malignancies spread to distant organs.

A systematic review of opioid prevalence in Australian residential aged care facilities.

OBJECTIVE: To systematically review the prevalence of opioid prescribing, dispensing and administration in Australian residential aged care facilities (RACFs). METHODS: MEDLINE, Embase, CINAHL, AgeLine, Web of Science Core Collection, InformIT and International Pharmaceutical Abstracts (inception to September 2021) were searched for studies reporting opioid prevalence in Australian RACFs. Regular and as-required (i.e. pro re nata, PRN) opioid uses were considered. Screening, data extraction and quality assessment were performed independently by two review authors. RESULTS: Twenty-three studies (n = 286,141 residents) reported opioid prevalence, of which 16 provided overall regular or PRN prescribing, dispensing or administration data. Five studies reported 28%-34% of residents were prescribed regular opioids over assessment periods ranging from one week to one month. Five studies reported 11%-42% of residents were prescribed PRN opioids over assessment periods ranging from one week to 30 months. Three studies reported 27%-50% of residents were dispensed an opioid over 12 months. Five studies reported 21%-29% were administered both regular and PRN opioids over 24 hours. Two studies reported 22%-42% of residents were administered PRN opioids over 1 week to 12 months. Two studies reported 6%-13% of residents were using doses >100 mg oral morphine equivalents/day. CONCLUSIONS: Up to half of the residents were dispensed opioids over 12 months. The prevalence of opioid prescribing, dispensing and administration was highly variable, suggesting the potential value of opioid quality indicators and analgesic stewardship interventions to ensure opioid appropriateness.

An optimized proliferation system of embryonic stem cells for generating the rat model with large fragment modification.

Rats have long been an ideal model for disease research in the field of biomedicine, but the bottleneck of in vitro culture of rat embryonic stem (ES) cells hindered the wide application as genetic disease models. Here, we optimized a special medium which we named 5N-medium for rat embryonic stem cells, which improved the in vitro cells with better morphology and higher pluripotency. We then established a drug selection schedule harboring a prior selection of 12 h that achieved a higher positive selection ratio. These treatments induced at least 50% increase of homologous recombination efficiency compared with conventional 2i culture condition. Moreover, the ratio of euploid ES clones also increased by 50% with a higher germline transmission rate. Finally, we successfully knocked in a 175 kb human Bacterial Artificial Chromosome (BAC) fragment to rat ES genome through recombinase mediated cassette exchange (RMCE). Hence, we provide a promising system for generating sophisticated rat models which could be benefit for biomedical researches.

Human RGR Gene and Associated Features of Age-Related Macular Degeneration in Models of Retina-Choriocapillaris Atrophy.

Age-related macular degeneration (AMD) is a progressive eye disease and the most common cause of blindness among the elderly. AMD is characterized by early atrophy of the choriocapillaris and retinal pigment epithelium (RPE). Although AMD is a multifactorial disease with many environmental and genetic risk factors, a hallmark of the disease is the origination of extracellular deposits, or drusen, between the RPE and Bruch membrane. Human retinal G-protein-coupled receptor (RGR) gene generates an exon-skipping splice variant of RGR-opsin (RGR-d; NP_001012740) that is a persistent component of small and large drusen. Herein, the findings show that abnormal RGR proteins, including RGR-d, are pathogenic in an animal retina with degeneration of the choriocapillaris, RPE, and photoreceptors. A frameshift truncating mutation resulted in severe retinal degeneration with a continuous band of basal deposits along the Bruch membrane. RGR-d produced less severe disease with choriocapillaris and RPE atrophy, including focal accumulation of abnormal RGR-d protein at the basal boundary of the RPE. Degeneration of the choriocapillaris was marked by a decrease in endothelial CD31 protein and choriocapillaris breakdown at the ultrastructural level. Fundus lesions with patchy depigmentation were characteristic of old RGR-d mice. RGR-d was mislocalized in cultured cells and caused a strong cell growth defect. These results uphold the notion of a potential hidden link between AMD and a high-frequency RGR allele.

Core outcome set for diabetes after pregnancy prevention across the life span: international Delphi study.

INTRODUCTION: Mothers with gestational diabetes mellitus (GDM) are at high risk of future diabetes. An active area of research examines health behavior change strategies in women within 5 years of a GDM pregnancy to prevent diabetes after pregnancy. We aimed to develop a core outcome set (COS) to facilitate synthesis and comparison across trials. RESEARCH DESIGN AND METHODS: Candidate outcomes were identified through systematic review and scored for importance (1-9) by healthcare professionals, researchers, and women with prior GDM through an international two-round electronic-Delphi survey. Outcomes retained required round two scores above prespecified thresholds (≥70% scoring 7-9) or expert panel endorsement when scores were indeterminate. The panel organized the COS by domain. RESULTS: 115 stakeholders participated in the survey and 56 completed both rounds. SD of scores decreased by 0.24 (95%CI 0.21 to 0.27) by round 2, signaling convergence. The final COS includes 19 domains (50 outcomes): diabetes (n=3 outcomes), other related diseases (n=3), complications in subsequent pregnancy (n=2), offspring outcomes (n=3), adiposity (n=4), cardiometabolic measures (n=5), glycemia (n=3), physical activity (n=2), diet (n=4), breast feeding (n=2), behavior change theory (n=5), diabetes-related knowledge (n=2), health literacy (n=1), social support (n=1), sleep (n=1), quality of life (n=1), program delivery (n=4), health economic evaluation (n=2), and diabetes risk screening (n=2). The seven outcomes endorsed by ≥90% were diabetes development and GDM recurrence, attending the postpartum diabetes screening and completing oral glucose tolerance testing and/or other glycemia measures, weight and total energy intake, and health behaviors in general. Among the 15 at the 80%-90% endorsement level, approximately half were specific elements related to the top 7, while the remainder related to diabetes knowledge, personal risk perception, motivation for change, program element completion, and health service use and cost. CONCLUSION: Researchers should collect and report outcomes from the breadth of domains in the COS.

Human Regulatory Dendritic Cells Develop From Monocytes in Response to Signals From Regulatory and Helper T Cells.

Dendritic cells (DCs) are powerful antigen presenting cells, derived from bone marrow progenitors (cDCs) and monocytes (moDCs), that can shape the immune response by priming either proinflammatory or tolerogenic immune effector cells. The cellular mechanisms responsible for the generation of DCs that will prime a proinflammatory or tolerogenic response are poorly understood. Here we describe a novel mechanism by which tolerogenic DCs are formed from monocytes. When human monocytes were cultured with CD4+FoxP3+ natural regulatory T cells (Tregs) and T helper cells (Th) from healthy donor blood, they differentiated into regulatory DCs (DC Reg ), capable of generating induced Tregs from naïve T cells. DC Reg exhibited morphology, surface phenotype, cytokine secretion, and transcriptome that were distinct from other moDCs including those derived from monocytes cultured with Th or with GM-CSF/IL-4, as well as macrophages (MΦ). Direct cell contact between monocytes, Tregs and Th, along with Treg-derived CTLA-4, IL-10 and TGF-ß, was required for the phenotypic differentiation of DC Reg , although only IL-10 was required for imprinting the Treg-inducing capacity of DC Reg . High ratios of Treg:Th, along with monocytes and DC Reg similar in function and phenotype to those induced in vitro, were present in situ in human colorectal cancer specimens. Thus, through the combined actions of Tregs and Th, monocytes differentiate into DCs with regulatory properties, forming a positive feedback loop to reinforce Treg initiated immune regulation. This mechanism may contribute to immune tolerance in tissues such as tumors, which contain an abundance of Tregs, Th and monocytes.

Effects of Time-Restricted Eating on Weight Loss and Other Metabolic Parameters in Women and Men With Overweight and Obesity: The TREAT Randomized Clinical Trial.

Importance: The efficacy and safety of time-restricted eating have not been explored in large randomized clinical trials. Objective: To determine the effect of 16:8-hour time-restricted eating on weight loss and metabolic risk markers. Interventions: Participants were randomized such that the consistent meal timing (CMT) group was instructed to eat 3 structured meals per day, and the time-restricted eating (TRE) group was instructed to eat ad libitum from 12:00 pm until 8:00 pm and completely abstain from caloric intake from 8:00 pm until 12:00 pm the following day. Design, Setting, and Participants: This 12-week randomized clinical trial including men and women aged 18 to 64 years with a body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) of 27 to 43 was conducted on a custom mobile study application. Participants received a Bluetooth scale. Participants lived anywhere in the United States, with a subset of 50 participants living near San Francisco, California, who underwent in-person testing. Main Outcomes and Measures: The primary outcome was weight loss. Secondary outcomes from the in-person cohort included changes in weight, fat mass, lean mass, fasting insulin, fasting glucose, hemoglobin A1c levels, estimated energy intake, total energy expenditure, and resting energy expenditure. Results: Overall, 116 participants (mean [SD] age, 46.5 [10.5] years; 70 [60.3%] men) were included in the study. There was a significant decrease in weight in the TRE (-0.94 kg; 95% CI, -1.68 to -0.20; P = .01), but no significant change in the CMT group (-0.68 kg; 95% CI, -1.41 to 0.05, P = .07) or between groups (-0.26 kg; 95% CI, -1.30 to 0.78; P = .63). In the in-person cohort (n = 25 TRE, n = 25 CMT), there was a significant within-group decrease in weight in the TRE group (-1.70 kg; 95% CI, -2.56 to -0.83; P < .001). There was also a significant difference in appendicular lean mass index between groups (-0.16 kg/m2; 95% CI, -0.27 to -0.05; P = .005). There were no significant changes in any of the other secondary outcomes within or between groups. There were no differences in estimated energy intake between groups. Conclusions and Relevance: Time-restricted eating, in the absence of other interventions, is not more effective in weight loss than eating throughout the day. Trial Registration: ClinicalTrials.gov Identifiers: NCT03393195 and NCT03637855.

Type 1 Diabetes Mellitus Virtual Patient Network as a Peer Support Community: Protocol for Social Network Analysis and Content Analysis.

BACKGROUND: Type 1 Diabetes Mellitus Virtual Patient Network (T1DM-VPN) is a private Facebook group for youths with type 1 diabetes mellitus (T1DM) in Canada intended to facilitate peer-to-peer support. It was built on the finding that stigma is prevalent among youth with T1DM and impedes self-management. OBJECTIVE: We aim to determine if T1DM-VPN provides support as intended and to ascertain what type of members provide support. Specifically, we will (1) identify text consistent with any one of 5 social support categories, (2) describe the network by visualizing its structure and reporting basic engagement statistics, and (3) determine whether being a designated peer leader is related to a member's centrality (ie, importance in the network) and how frequently they offer social support. METHODS: We will manually extract interaction data from the Facebook group (posts, comments, likes/reactions, seen) generated from June 21, 2017 (addition of first member), to March 1, 2020. Two researchers will independently code posts and comments according to an existing framework of 5 social support categories-informational, emotional, esteem, network, and tangible-with an additional framework for nonsocial support categories. We will calculate how frequently each code is used. We will also report basic engagement statistics (eg, number of posts made per person-month) and generate a visualization of the network. We will identify stable time intervals in the history of T1DM-VPN by modeling monthly membership growth as a Poisson process. Within each interval, each member's centrality will be calculated and standardized to that of the most central member. We will use a centrality formula that considers both breadth and depth of connections (centrality = 0.8 × total No. of connections + 0.2 × total No. of interactions). Finally, we will construct multivariate linear regression models to assess whether peer leader status predicts member centrality and the frequency of offering social support. Other variables considered for inclusion in the models are gender and age at diagnosis. RESULTS: T1DM-VPN was launched in June 2017. As of March 1, 2020, it has 196 patient-members. This research protocol received ethics approval from the McGill University Health Centre Research Ethics Board on May 20, 2020. Baseline information about each group member was collected upon addition into the group, and collection of interaction data is ongoing as of May 2020. CONCLUSIONS: This content analysis and social network analysis study of a virtual patient network applies epidemiological methods to account for dynamic growth and activity. The results will allow for an understanding of the topics of importance to youth with T1DM and how a virtual patient network evolves over time. This work is intended to serve as a foundation for future action to help youth improve their experience of living with diabetes. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/18714.

Pharmacological intervention for diabetes after pregnancy prevention in women with prior gestational diabetes: A scoping review.

Women with previous gestational diabetes mellitus (GDM) are at increased risk of developing diabetes after pregnancy (DAP), especially 5-10 years postpartum. Two well-known diabetes prevention trials demonstrated a significant reduction in DAP incidence using metformin and troglitazone; however, since their publication, several novel classes of anti-hyperglycemic agents have emerged. This review aimed to conduct a systematic literature search for new evidence in support of pharmacotherapy in DAP prevention and to analyze the results based on special considerations for women of reproductive potential. The only studies whose primary outcome was DAP incidence were those examining metformin, the thiazolidinediones troglitazone and pioglitazone, and the dipeptidyl peptidase-4 inhibitor vildagliptin. Metformin was effective in DAP reduction and was well tolerated, but participants were on average 12 years beyond their GDM pregnancy. Troglitazone was also shown to prevent DAP, but was withdrawn from the market due to hepatotoxicity. There was no comparator arm in the pioglitazone study, which limits its interpretability. The vildagliptin study was underpowered. There are ongoing trials with glucagon-like peptide 1 receptor agonists and sodium-glucose cotransporter 2 inhibitors, but none with diabetes incidence as a primary outcome. This review highlights the limited evidence base for pharmacological prevention of DAP.

A truncating mutation in the autophagy gene UVRAG drives inflammation and tumorigenesis in mice.

Aberrant autophagy is a major risk factor for inflammatory diseases and cancer. However, the genetic basis and underlying mechanisms are less established. UVRAG is a tumor suppressor candidate involved in autophagy, which is truncated in cancers by a frameshift (FS) mutation and expressed as a shortened UVRAGFS. To investigate the role of UVRAGFS in vivo, we generated mutant mice that inducibly express UVRAGFS (iUVRAGFS). These mice are normal in basal autophagy but deficient in starvation- and LPS-induced autophagy by disruption of the UVRAG-autophagy complex. iUVRAGFS mice display increased inflammatory response in sepsis, intestinal colitis, and colitis-associated cancer development through NLRP3-inflammasome hyperactivation. Moreover, iUVRAGFS mice show enhanced spontaneous tumorigenesis related to age-related autophagy suppression, resultant ß-catenin stabilization, and centrosome amplification. Thus, UVRAG is a crucial autophagy regulator in vivo, and autophagy promotion may help prevent/treat inflammatory disease and cancer in susceptible individuals.

Real-world heart rate norms in the Health eHeart study.

Emerging technology allows patients to measure and record their heart rate (HR) remotely by photoplethysmography (PPG) using smart devices like smartphones. However, the validity and expected distribution of such measurements are unclear, making it difficult for physicians to help patients interpret real-world, remote and on-demand HR measurements. Our goal was to validate HR-PPG, measured using a smartphone app, against HR-electrocardiogram (ECG) measurements and describe out-of-clinic, real-world, HR-PPG values according to age, demographics, body mass index, physical activity level, and disease. To validate the measurements, we obtained simultaneous HR-PPG and HR-ECG in 50 consecutive patients at our cardiology clinic. We then used data from participants enrolled in the Health eHeart cohort between 1 April 2014 and 30 April 2018 to derive real-world norms of HR-PPG according to demographics and medical conditions. HR-PPG and HR-ECG were highly correlated (Intraclass correlation = 0.90). A total of 66,788 Health eHeart Study participants contributed 3,144,332 HR-PPG measurements. The mean real-world HR was 79.1 bpm ± 14.5. The 95th percentile of real-world HR was ≤110 in individuals aged 18-45, ≤100 in those aged 45-60 and ≤95 bpm in individuals older than 60 years old. In multivariable linear regression, the number of medical conditions, female gender, increasing body mass index, and being Hispanic was associated with an increased HR, whereas increasing age was associated with a reduced HR. Our study provides the largest real-world norms for remotely obtained, real-world HR according to various strata and they may help physicians interpret and engage with patients presenting such data.

Development of a core outcome set for diabetes after pregnancy prevention interventions (COS-DAP): a study protocol.

BACKGROUND: Gestational diabetes mellitus (GDM) increases the risk of adverse short- and long-term outcomes, including development of type 2 diabetes. The US Diabetes Prevention Program demonstrates this risk can be halved with an intensive health behavior change intervention in women with pre-diabetes averaging 12 years since a GDM pregnancy. In recent years, the number of studies looking at changing the behaviors of women with previous GDM closer to the time of delivery has steadily grown, but reported outcomes vary and most studies are not long enough or large enough to examine incident diabetes. This initiative aims to develop a core outcome set (COS) for interventions seeking to prevent diabetes after pregnancy (DAP) in both women with prior GDM and their families. METHODS: The COS-DAP project will use established COS methodology, in four stages: (1) a systematic literature review of DAP prevention intervention studies following GDM; (2) discussion and cataloguing of outcomes measured and implementation components at an investigator meeting; (3) a two-round online Delphi survey aimed at prioritizing the identified outcomes; and (4) a consensus meeting with key stakeholders to review, discuss, and refine suitable COS measures, using nominal group technique. DISCUSSION: COS-DAP aims to develop a COS for health behavior change interventions to prevent DAP. The COS is expected to enhance opportunities for comparison of future studies and allow for better synthesis of the effects. The inclusion of multiple stakeholder perspectives will increase the final COSs applicability and relevance. TRIAL REGISTRATION: Comet Initiative, COMET 1083; PROSPERO, CRD42018084853 . Registered in prospero on 03/01/2018.

Developing Trauma Audit Filters for Regional Referral Hospitals in Cameroon: Mixed-Methods Approach.

BACKGROUND: Injuries are a leading cause of death and disability worldwide. Developing countries account for 90% of injury-related deaths globally. Trauma audit filters can facilitate trauma quality improvement initiatives and reduce the injury burden. Little is known about context-appropriate trauma audit filters for developing countries such as Cameroon. This study aimed to (1) develop context-appropriate trauma audit filters for the setting of a regional referral hospital in Cameroon and (2) to assess the barriers and facilitators to their implementation. METHODS: Feasible audit filters were identified by a panel of Cameroonian surgeons using the Delphi technique. A Likert scale (1 to 5, with 5 as "Most Useful") was used to rank the filters for utility in a regional referral hospital setting, analyzed using the median and interquartile range. Semistructured interviews were conducted with 16 health care providers from three hospital facilities to explore their perceptions of supervision and support they receive from hospital administration, availability of resources, their work environment, and potential concerns and impacts of trauma audit filters. Interviews were coded and thematically analyzed. RESULTS: Within a panel of seven surgeons, 23 of 40 trauma audit filter variables met majority consensus criteria. Twenty-one of these, comprising mostly of primary survey and basic resuscitation techniques, had a median score of ≥4. Filters meeting consensus include, but are not limited to, vitals obtained, breathing assessment made, and two large bore intravenous established within 15 min of arrival; patient with open fracture receives intravenous antimicrobials within 1 h of arrival; patients with suspected spine injury are immobilized and given X-ray. The provider interviews revealed that the barriers to providing quality care were limited human and material resources and patients' inability to pay. Regular staff training in trauma care and the belief that trauma audit filters would potentially streamline work practices and improve the quality of care were cited as promoters of successful implementation. CONCLUSIONS: Primary survey and basic resuscitative techniques are key elements of context-appropriate audit filters in Cameroon. Such audit filters may not be costly, require complex infrastructure, or equipment that exceed the site's capabilities. Proper staff orientation and participation in the use of trauma audit filters, as quality improvement tools, are key to local buy-in and implementation success.

Risk Factors for Substance Use Among Youth Experiencing Homelessness.

BACKGROUND: Youth experiencing homelessness are at high risk for frequent substance use. This study examines individual, interpersonal, and contextual factors associated with substance use among such youth, age 13-24. METHODS: Data were collected through computer-assisted structured interviews with participants (N=474) recruited at service agencies in Los Angeles. RESULTS: Youth had experienced over two years of homelessness on average. Almost a third used substances frequently; significant risk factors included delinquency, sensation seeking, and ongoing homelessness. Time spent in clubs and organizations was protective. CONCLUSIONS: Providing housing and services to curb delinquency may help protect youth from becoming frequent substance users.

Large-scale identification of human cerebrovascular proteins: Inter-tissue and intracerebral vascular protein diversity.

The human cerebrovascular system is responsible for regulating demand-dependent perfusion and maintaining the blood-brain barrier (BBB). In addition, defects in the human cerebrovasculature lead to stroke, intracerebral hemorrhage, vascular malformations, and vascular cognitive impairment. The objective of this study was to discover new proteins of the human cerebrovascular system using expression data from the Human Protein Atlas, a large-scale project which allows public access to immunohistochemical analysis of human tissues. We screened 20,158 proteins in the HPA and identified 346 expression patterns correlating to blood vessels in human brain. Independent experiments showed that 51/52 of these distributions could be experimentally replicated across different brain samples. Some proteins (40%) demonstrated endothelial cell (EC)-enriched expression, while others were expressed primarily in vascular smooth muscle cells (VSMC; 18%); 39% of these proteins were expressed in both cell types. Most brain EC markers were tissue oligospecific; that is, they were expressed in endothelia in an average of 4.8 out of 9 organs examined. Although most markers expressed in endothelial cells of the brain were present in all cerebral capillaries, a significant number (21%) were expressed only in a fraction of brain capillaries within each brain sample. Among proteins found in cerebral VSMC, virtually all were also expressed in peripheral VSMC and in non-vascular smooth muscle cells (SMC). Only one was potentially brain specific: VHL (Von Hippel-Lindau tumor suppressor). HRC (histidine rich calcium binding protein) and VHL were restricted to VSMC and not found in non-vascular tissues such as uterus or gut. In conclusion, we define a set of brain vascular proteins that could be relevant to understanding the unique physiology and pathophysiology of the human cerebrovasculature. This set of proteins defines inter-organ molecular differences in the vasculature and confirms the broad heterogeneity of vascular cells within the brain.

T Cell Subset and Stimulation Strength-Dependent Modulation of T Cell Activation by Kv1.3 Blockers.

Kv1.3 is a voltage-gated potassium channel expressed on T cells that plays an important role in T cell activation. Previous studies have shown that blocking Kv1.3 channels in human T cells during activation results in reduced calcium entry, cytokine production, and proliferation. The aim of the present study was to further explore the effects of Kv1.3 blockers on the response of different human T cell subsets under various stimulation conditions. Our studies show that, unlike the immune suppressor cyclosporine A, the inhibitory effect of Kv1.3 blockers was partial and stimulation strength dependent, with reduced inhibitory efficacy on T cells under strengthened anti-CD3/CD28 stimulations. T cell responses to allergens including house dust mites and ragweed were partially reduced by Kv1.3 blockers. The effect of Kv1.3 inhibition was dependent on T cell subsets, with stronger effects on CCR7- effector memory compared to CCR7+ central memory CD4 T cells. Calcium entry studies also revealed a population of CD4 T cells resistant to Kv1.3 blockade. Activation of CD4 T cells was accompanied with an increase in Kv1.3 currents but Kv1.3 transcripts were found to be reduced, suggesting a posttranscriptional mechanism in the regulation of Kv1.3 activities. In summary, Kv1.3 blockers inhibit T cell activation in a manner that is highly dependent on the T cell identity and stimulation strength, These findings suggest that Kv1.3 blockers inhibit T cells in a unique, conditional manner, further refining our understanding of the therapeutic potential of Kv1.3 blockers.

Fluorescence-Based Real-Time Activity Assays to Identify RNase P Inhibitors.

Transfer RNA is transcribed as precursor molecules that are processed before participating in translation catalyzed by the ribosome. Ribonuclease P is the endonuclease that catalyzes the 5' end maturation of precursor tRNA and it is essential for cell survival. Bacterial RNase P has a distinct subunit composition compared to the eukaryal counterparts; therefore, it is an attractive antibacterial target. Here, we describe a real-time fluorescence-based RNase P activity assay using fluorescence polarization/anisotropy with a 5' end fluorescein-labeled pre-tRNAAsp substrate. This FP/FA assay is sensitive, robust, and easy to transition to a high-throughput mode and it also detects ligands that interact with pre-tRNA. We apply this FP/FA assay to measure Bacillus subtilis RNase P activity under single and multiple turnover conditions in a continuous format and a high-throughput screen of inhibitors, as well as determining the dissociation constant of pre-tRNA for small molecules.