Microbial ligand-independent regulation of lymphopoiesis by NOD1.

Aberrant differentiation of progenitor cells in the hematopoietic system is known to severely impact host immune responsiveness. Here we demonstrate that NOD1, a cytosolic innate sensor of bacterial peptidoglycan, also functions in murine hematopoietic cells as a major regulator of both the generation and differentiation of lymphoid progenitors as well as peripheral T lymphocyte homeostasis. We further show that NOD1 mediates these functions by facilitating STAT5 signaling downstream of hematopoietic cytokines. In steady-state, loss of NOD1 resulted in a modest but significant decrease in numbers of mature T, B and natural killer cells. During systemic protozoan infection this defect was markedly enhanced, leading to host mortality. Lack of functional NOD1 also impaired T cell-dependent anti-tumor immunity while preventing colitis. These findings reveal that, in addition to its classical role as a bacterial ligand receptor, NOD1 plays an important function in regulating adaptive immunity through interaction with a major host cytokine signaling pathway.

Circadian Regulation of Drug Responses: Toward Sex-Specific and Personalized Chronotherapy.

Today's challenge for precision medicine involves the integration of the impact of molecular clocks on drug pharmacokinetics, toxicity, and efficacy toward personalized chronotherapy. Meaningful improvements of tolerability and/or efficacy of medications through proper administration timing have been confirmed over the past decade for immunotherapy and chemotherapy against cancer, as well as for commonly used pharmacological agents in cardiovascular, metabolic, inflammatory, and neurological conditions. Experimental and human studies have recently revealed sexually dimorphic circadian drug responses. Dedicated randomized clinical trials should now aim to issue personalized circadian timing recommendations for daily medical practice, integrating innovative technologies for remote longitudinal monitoring of circadian metrics, statistical prediction of molecular clock function from single-timepoint biopsies, and multiscale biorhythmic mathematical modelling. Importantly, chronofit patients with a robust circadian function, who would benefit most from personalized chronotherapy, need to be identified. Conversely, nonchronofit patients could benefit from the emerging pharmacological class of chronobiotics targeting the circadian clock.

PD-1 Inhibitory Receptor Downregulates Asparaginyl Endopeptidase and Maintains Foxp3 Transcription Factor Stability in Induced Regulatory T Cells.

CD4+ T cell differentiation into multiple T helper (Th) cell lineages is critical for optimal adaptive immune responses. This report identifies an intrinsic mechanism by which programmed death-1 receptor (PD-1) signaling imparted regulatory phenotype to Foxp3+ Th1 cells (denoted as Tbet+iTregPDL1 cells) and inducible regulatory T (iTreg) cells. Tbet+iTregPDL1 cells prevented inflammation in murine models of experimental colitis and experimental graft versus host disease (GvHD). Programmed death ligand-1 (PDL-1) binding to PD-1 imparted regulatory function to Tbet+iTregPDL1 cells and iTreg cells by specifically downregulating endo-lysosomal protease asparaginyl endopeptidase (AEP). AEP regulated Foxp3 stability and blocking AEP imparted regulatory function in Tbet+iTreg cells. Also, Aep-/- iTreg cells significantly inhibited GvHD and maintained Foxp3 expression. PD-1-mediated Foxp3 maintenance in Tbet+ Th1 cells occurred both in tumor infiltrating lymphocytes (TILs) and during chronic viral infection. Collectively, this report has identified an intrinsic function for PD-1 in maintaining Foxp3 through proteolytic pathway.

A lithium-isotope perspective on the evolution of carbon and silicon cycles.

The evolution of the global carbon and silicon cycles is thought to have contributed to the long-term stability of Earth's climate1-3. Many questions remain, however, regarding the feedback mechanisms at play, and there are limited quantitative constraints on the sources and sinks of these elements in Earth's surface environments4-12. Here we argue that the lithium-isotope record can be used to track the processes controlling the long-term carbon and silicon cycles. By analysing more than 600 shallow-water marine carbonate samples from more than 100 stratigraphic units, we construct a new carbonate-based lithium-isotope record spanning the past 3 billion years. The data suggest an increase in the carbonate lithium-isotope values over time, which we propose was driven by long-term changes in the lithium-isotopic conditions of sea water, rather than by changes in the sedimentary alterations of older samples. Using a mass-balance modelling approach, we propose that the observed trend in lithium-isotope values reflects a transition from Precambrian carbon and silicon cycles to those characteristic of the modern. We speculate that this transition was linked to a gradual shift to a biologically controlled marine silicon cycle and the evolutionary radiation of land plants13,14.

Phanerozoic flooding of North America and the Great Unconformity.

The flooding record of North America has been used to infer patterns of global erosion and sea level in deep time. Here, we utilize the geospatial dimension of the stratigraphic record provided by the Macrostrat database, and patterns of erosion from thermochronology, to resolve local tectonic subsidence from global sea level. We show that the flooding history of North America correlates in space and time with continent-facing subduction along active margins, consistent with subduction-driven dynamic topographic subsidence of the continental interior. Nonetheless, the continentally aggregated flooding signal of North America is an exaggerated global M-curve of Phanerozoic sea level. This coincidence relates to the closing of the geodynamic loop of the supercontinent cycle: Subduction under North America accommodated both the makeup and breakup of Pangaea, which, coupled with changing ridge length, flattened hypsometry, and increased sea level both locally and globally. The sole Phanerozoic exception to this pattern of global sea level tracking North American near-field geodynamics is the Cambrian Sauk transgression. We argue that this is a far-field record of the inception of circum-Gondwanan subduction, independent of North America, which significantly flattened Earth's hypsometry. This hypsometric flattening displaced ocean water globally, flooding tectonically passive North America to seal the Great Unconformity.

The rise of New Guinea and the fall of Neogene global temperatures.

The ~2,000-km-long Central Range of New Guinea is a hotspot of modern carbon sequestration due to the chemical weathering of igneous rocks with steep topography in the warm wet tropics. These high mountains formed in a collision between the Australian plate and ophiolite-bearing volcanic arc terranes, but poor resolution of the uplift and exhumation history has precluded assessments of the impact on global climate change. Here, we develop a palinspastic reconstruction of the Central Range orogen with existing surface geological constraints and seismic data to generate time-temperature paths and estimate volumes of eroded material. New (U-Th)/He thermochronology data reveal rapid uplift and regional denudation between 10 and 6 Mya. Erosion fluxes from the palinspastic reconstruction, calibrated for time with the thermochronological data, were used as input to a coupled global climate and weathering model. This model estimates 0.6 to 1.2 °C of cooling associated with the Late Miocene rise of New Guinea due to increased silicate weathering alone, and this CO2 sink continues to the present. Our data and modeling experiments support the hypothesis that tropical arc-continent collision and the rise of New Guinea contributed to Neogene cooling due to increased silicate weathering.

Why does circadian timing of administration matter for immune checkpoint inhibitors' efficacy?

BACKGROUND: Tolerability and antitumour efficacy of chemotherapy and radiation therapy can vary largely according to their time of administration along the 24-h time scale, due to the moderation of their molecular and cellular mechanisms by circadian rhythms. Recent clinical data have highlighted a striking role of dosing time for cancer immunotherapy, thus calling for a critical evaluation. METHODS: Here, we review the clinical data and we analyse the mechanisms through which circadian rhythms can influence outcomes on ICI therapies. We examine how circadian rhythm disorders can affect tumour immune microenvironment, as a main mechanism linking the circadian clock to the 24-h cycles in ICIs antitumour efficacy. RESULTS: Real-life data from 18 retrospective studies have revealed that early time-of-day (ToD) infusion of immune checkpoint inhibitors (ICIs) could enhance progression-free and/or overall survival up to fourfold compared to late ToD dosing. The studies involved a total of 3250 patients with metastatic melanoma, lung, kidney, bladder, oesophageal, stomach or liver cancer from 9 countries. Such large and consistent differences in ToD effects on outcomes could only result from a previously ignored robust chronobiological mechanism. The circadian timing system coordinates cellular, tissue and whole-body physiology along the 24-h timescale. Circadian rhythms are generated at the cellular level by a molecular clock system that involves 15 specific clock genes. The disruption of circadian rhythms can trigger or accelerate carcinogenesis, and contribute to cancer treatment failure, possibly through tumour immune evasion resulting from immunosuppressive tumour microenvironment. CONCLUSIONS AND PERSPECTIVE: Such emerging understanding of circadian rhythms regulation of antitumour immunity now calls for randomised clinical trials of ICIs timing to establish recommendations for personalised chrono-immunotherapies with current and forthcoming drugs.

Long-Term Effectiveness and Durability of COVID-19 Vaccination Among Patients With Inflammatory Bowel Disease.

BACKGROUND AND AIMS: COVID-19 vaccination prevents severe disease in most patients with inflammatory bowel disease (IBD), but immunosuppressive medications can blunt serologic response. We followed adults with IBD for >1 year post-COVID-19 vaccination to describe factors associated with SARS-CoV-2 infection after vaccination, evaluate for a protective SARS-CoV-2 antibody level, characterize SARS-CoV-2 antibody persistence, and identify factors associated with humoral immune response durability. METHODS: Using a prospective cohort of COVID-19 immunized adults with IBD, we analyzed factors associated with SARS-CoV-2 infection after vaccination. We evaluated for an association between SARS-CoV-2 antibody level 12 weeks postvaccination and subsequent SARS-CoV-2 infection and assessed for a threshold of protection using receiver-operating characteristic curve analysis. We then conducted a separate analysis evaluating factors associated with persistence of SARS-CoV-2 antibodies 52 weeks postimmunization. RESULTS: Almost half (43%) of 1869 participants developed COVID-19 after vaccination, but most infections were mild, and <1% required hospitalization. Older age and corticosteroid use were associated with a decreased risk of SARS-CoV-2 infection postvaccination (50-59 years of age vs 18-29 years of age: adjusted hazard ratio, 0.57; 95% confidence interval, 0.44-0.74; steroid users vs nonusers: adjusted hazard ratio, 0.58; 95% confidence interval, 0.39-0.87). Most (98%) participants had detectable antibody levels at 52 weeks postvaccination. Antibody levels at 12 weeks and number of vaccine doses were positively associated with higher antibody levels at 52 weeks, while anti-tumor necrosis factor α therapy was negatively associated. CONCLUSIONS: COVID-19 vaccination generates an effective and durable protective response for the vast majority of adults with IBD, including vulnerable populations such as corticosteroid users and older individuals. Patients with IBD benefit from COVID-19 booster vaccination.

Risk of Small Intestine Cancer in Inflammatory Bowel Disease: A Propensity-Matched Study from a Large Multi-Center Database in the United States.

INTRODUCTION: The risk of small bowel cancer (SBC) in inflammatory bowel disease (IBD) is unclear. We compared the recent trends of SBC in patients with IBD and stratified them based on disease type. METHODS: We used TriNetX database to access the electronic health records for patients with IBD, ulcerative colitis (UC) and Crohn's disease (CD) from 2005-2024. We used propensity score matching to compare the rate of SBC in patients with IBD, UC, and CD compared to the general population. We adjusted for all known confounders. RESULTS: From 2010-2024, there was an increasing trend of diagnosed SBC in patients with IBD, with an Average Annual Percentage Change (AAPC) of 3.2% (P<0.001). Patients with CD (aHR = 4.83; 95% CI: 3.58 - 6.53; P < .0001) had an increased risk of SBC compared to the general population without IBD, as well as patients with UC (aHR = 2.28; 95% CI: 1.65 - 3.14; P < .0001). The ileum was the most common location across all subgroups. CONCLUSION: Both patients with CD and, interestingly, UC had an elevated risk for developing SBC compared to the general population.

Comparative Effectiveness of Upadacitinib and Tofacitinib in Ulcerative Colitis: A US Propensity-Matched Cohort Study.

INTRODUCTION: There are limited real-world data comparing the effectiveness of upadacitinib and tofacitinib in patients with ulcerative colitis (UC). METHODS: We conducted a retrospective cohort study using TriNetX, a multi-institutional database, to compare the effectiveness of upadacitinib and tofacitinib in patients with UC. The primary aim was to assess the risk of a composite outcome of hospitalization requiring intravenous steroids and/or colectomy within 6 and 12 months. One-to-one propensity score matching was performed for demographics, comorbid conditions, mean hemoglobin, C-reactive protein, albumin, and calprotectin, and prior UC medications including recent oral or intravenous steroid use between the cohorts. Risk was expressed as adjusted odds ratio (aOR) with 95% confidence intervals (CI). RESULTS: There were 526 patients in the upadacitinib cohort (mean age 40.4 ± 16.3, 44.8% female sex, 76.6% White race) and 1,149 patients in the tofacitinib cohort (mean age 42 ± 17.1, 41.9% female sex, 76% White race). After propensity score matching, there was no significant difference in the risk of the composite outcome of need for intravenous steroids and/or colectomy within 6 months (aOR 0.75, 95% CI 0.49-1.09). However, there was a lower risk of the composite outcome (aOR 0.63, 95% CI 0.44-0.89) in the upadacitinib cohort compared with the tofacitinib cohort within 12 months. There was no difference in the risk of intravenous steroid use (aOR 0.70, 95% CI 0.48-1.02) but lower risk of colectomy (aOR 0.46, 95% CI 0.27-0.79). In sensitivity analysis, there was also a lower risk of the composite outcome (aOR 0.64, 95% CI 0.44-0.94), including lower risk of intravenous steroid use (aOR 0.67, 95% CI 0.45-0.99) and colectomy (aOR 0.49, 95% CI 0.26-0.92) in the upadacitinib cohort compared with the tofacitinib cohort within 12 months. DISCUSSION: This study utilizing real-world data showed that upadacitinib was associated with improved disease-specific outcomes at 12 months compared with tofacitinib in patients with UC.

The Natural History After Ileal Pouch-Anal Anastomosis for Ulcerative Colitis: A Population-Based Cohort Study From the United States.

INTRODUCTION: There are limited data regarding the natural history after ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC). The principal objectives of this study were to identify 4 key outcomes in the natural history after IPAA within 1, 3, 5, and 10 years: the incidence of pouchitis, Crohn's-like disease of the pouch, use of advanced therapies after IPAA, and pouch failure requiring excision in a network of electronic health records. METHODS: We performed a retrospective cohort study in TriNetX, a research network of electronic health records. In addition to evaluating incidence rates, we also sought to identify factors associated with pouchitis and advanced therapy use within 5 years of IPAA after 1:1 propensity score matching, expressed as adjusted hazard ratios (aHRs). RESULTS: Among 1,331 patients who underwent colectomy with IPAA for UC, the incidence of pouchitis increased from 58% in the first year after IPAA to 72% at 10 years after IPAA. After propensity score matching, nicotine dependence (aHR 1.61, 95% confidence interval [CI] 1.19-2.18), antitumor necrosis factor therapy (aHR 1.33, 95% CI 1.13-1.56), and vedolizumab prior to colectomy (aHR 1.44, 95% CI 1.06-1.96) were associated with an increased risk of pouchitis in the first 5 years after IPAA. The incidence of Crohn's-like disease of the pouch increased to 10.3% within 10 years of IPAA while pouch failure increased to 4.1%. The incidence of advanced therapy use peaked at 14.4% at 10 years after IPAA. DISCUSSION: The incidence of inflammatory conditions of the pouch remains high in the current era, with 14% of patients requiring advanced therapies after IPAA.

Patients With Inflammatory Bowel Disease Are at Increased Risk of Hospitalization Due to Respiratory Syncytial Virus.

INTRODUCTION: Patients with inflammatory bowel disease (IBD) are at increased risk of developing respiratory infections. Respiratory syncytial virus (RSV) is a common respiratory virus with adverse outcomes in older adults. This study aimed to determine whether patients with IBD are at increased risk of a serious infection due to RSV. METHODS: We conducted a retrospective study using the multi-institutional research network TriNetX to assess the risk of hospitalization in a cohort of patients with IBD compared with that in a non-IBD control cohort with RSV infection from January 1, 2007, to February 27, 2023. One-to-one (1:1) propensity score matching was performed for demographic variables and RSV risk factors between the 2 cohorts. Risk was expressed as adjusted odds ratio (aOR) with 95% confidence interval (CI). RESULTS: There were 794 patients in the IBD-RSV cohort and 93,074 patients in the non-IBD-RSV cohort. The mean age of the IBD-RSV cohort was 55.6 ± 20 years, 59% were female, 80% were White, and 56.9% had Crohn's disease. The IBD-RSV cohort was at an increased risk of hospitalization (aOR 1.30, 95% CI 1.06-1.59). There was no difference in the risk (aOR 0.83, 95% CI 0.58-1.19) of a composite outcome of hospitalization-related complications between the 2 cohorts. Recent systemic corticosteroid use (<3 months) was associated with an increased risk of hospitalization (aOR 1.86, 95% CI 1.30-2.59) in the IBD-RSV cohort. DISCUSSION: We found that adult patients with IBD and RSV infection are at an increased risk of hospitalization and may benefit from the new RSV vaccine recommended for adults aged 60 years and older.

Utility of a Third Heplisav-B Dose in Patients With Inflammatory Bowel Disease Without Immunity After 2-Dose Heplisav-B Vaccination.

INTRODUCTION: Hepatitis B virus (HBV) vaccination is recommended in patients with inflammatory bowel disease (IBD). Although the 2-dose Heplisav-B vaccine has proven effective, more than 20% of patients with IBD do not seroconvert. We prospectively evaluated the effectiveness of a third Heplisav-B dose in patients with IBD lacking HBV immunity despite 2-dose vaccination. METHODS: Adults with IBD who had received 2-dose Heplisav-B vaccination between 2018 and 2023 were identified. Seroconversion was defined as hepatitis B surface antibody (HBsAb) ≥ 10 IU/L measured at ≥4 weeks after vaccination. Patients who did not seroconvert were prospectively offered a third Heplisav-B dose, followed by repeat HBsAb measurement. Demographic, clinical, medication, and vaccination data were compared between those who did and did not seroconvert. RESULTS: Of 192 patients identified, 71.9% (138/192) seroconverted after 2-dose Heplisav-B vaccination. The 54 patients (28.1%) who did not seroconvert were more likely to be male, have diabetes, chronic kidney disease, or elevated Charlson Comorbidity Index. Of the 54 patients, 30 (55.6%) elected to receive a third Heplisav-B dose, with 56.7% (17/30) achieving seroconversion (median HBsAb titer 376 IU/L, IQR 47-1,000 IU/L) despite a median intervaccination time of 416 days (IQR 90.8-667.8). No differences were noted between patients who did vs did not seroconvert after third-dose vaccination. DISCUSSION: In patients with IBD lacking HBV immunity despite 2-dose Heplisav-B vaccination, administration of a third dose resulted in a 56.7% seroconversion rate. Our results suggest that administration of an additional Heplisav-B dose may be an effective strategy in patients lacking immunity despite primary 2-dose vaccination.

Baseline Clinical Factors Are Associated With Risk of Complications in Crohn's Disease: Appraisal of the American Gastroenterological Association Clinical Care Pathway.

INTRODUCTION: The American Gastroenterological Association (AGA) has compiled risk factors that may be predictive of disease complications in Crohn's disease (CD) and ulcerative colitis (UC). The aim of this study was to evaluate the performance of the AGA risk factors for risk stratification in UC and CD. METHODS: We included participants of 2 cohorts: the Ocean State Crohn's and Colitis Area Registry cohort and the Mayo Clinic cohort. Baseline clinical risk factors were extracted according to the AGA pathway. Our primary end point was defined as follows: (i) any inflammatory bowel disease related-hospitalization, (ii) any inflammatory bowel disease-related bowel surgery, or (iii) any progression of disease. We analyzed the association of the number of AGA risk factors with our end point. Statistical multivariable modeling was performed with Cox proportional hazards model. RESULTS: A total of 412 patients with CD were included. Comparing ≥3 risk factors with 0-1 risk factor, we found a significantly increased risk of complications in both the Ocean State Crohn's and Colitis Area Registry cohort (hazard ratio [HR] 2.75, 95% confidence interval 1.71-4.41) and Mayo Clinic cohort (HR 2.07, 95% confidence interval 1.11-3.84). Diagnosis at younger age (HR 2.07), perianal disease (HR 1.99), and B2/B3 behavior (HR 1.92) were significantly associated with disease complications. We did not observe a consistent association between number of risk factors nor any specific individual risk factors and risk of disease complications in the 265 patients with UC included. DISCUSSION: We found a significant association between the number of AGA risk factors and the risk of disease complication in CD; this association was not significant in UC. The presence of ≥ 3 risk factors in CD leads to the highest risk of complications. The AGA care pathway is a useful tool to stratify patients who are at higher risk of disease complications in patients with CD.

Utilization of opportunistic cervical cancer screening in Nigeria.

BACKGROUND: While various interventions have been conducted to decrease cervical cancer's burden in Nigeria, no study has examined the trends in cervical cancer screening uptake over time. The present study sought to fill this gap in knowledge using data collected at Jos University Teaching Hospital (JUTH) in Nigeria. METHODS: Data collected continuously between 2006 and 2016 were analyzed to identify trends in screening uptake, changes in risk factors for cervical cancer, and to identify factors for women screened at Jos University Teaching Hospital (JUTH) in Jos, Nigeria. Categorical analyses and logistic regression models were used to describe patient characteristics by year, and to identify factors associated with repeated screening uptake. RESULTS: A total of 14,088 women who were screened between 2006 and 2016 were included in the database; 2,800 women had more than one screening visit. Overall, screening uptake differed significantly by year. On average women were first screened at age 38. About 2% of women screened were women living with HIV. Most women (86%) had normal pap smear at first screening, with the greatest decreased risk of abnormalities observed between 2011 and 2014. Odds of a follow-up screening after a normal result decreased significantly between 2008 and 2016 compared to women screened in 2006 and 2007. Finally, women living with HIV had increased odds of follow-up screening after having a normal pap smear. CONCLUSIONS: These findings contribute to our understanding of the potential social and health system barriers to cervical cancer control in Nigeria. The findings may assist policy makers to design interventions to increase access and compliance to recommended screening schedules in this vulnerable population.

Glucagon-like Peptide-1 Receptor Agonists and Capsule Endoscopy in Patients with Diabetes: A Matched Cohort Study.

BACKGROUND AND AIMS: Video capsule endoscopy (VCE) is valuable for assessing conditions like gastrointestinal bleeding, anemia, and inflammatory bowel disease. Glucagon-like peptide-1 receptor agonists (GLP-1 RA) are prescribed for diabetes and weight loss, with their pharmacologic effects including delaying gastric emptying. This study investigates the impact of GLP-1 RA usage on VCE outcomes in patients with diabetes. METHODS: This retrospective cohort study involves patients with diabetes undergoing VCE while on GLP-1 RA, matched 1:1 ratio with controls based on demographics and diabetes related factors, who are not on GLP-RA. The primary outcome is gastric transit time in VCE studies, with secondary outcome being incomplete small bowel evaluation and the small bowel transit time. RESULTS: In the 68 GLP-1 RA patient cohort, five (7%) experienced VCE failure to pass through the stomach, while all controls passed successfully (p=0.06). GLP-1 RA patients had longer gastric transit time (99.3 ± 134.2 minutes) compared to controls (25.3 ± 31.6 minutes, p <0.001). Multivariate analysis revealed GLP-1 RA usage was associated with increased gastric transit time by 74.5 minutes (CI: 33.8-115.2, p <0.001) compared to controls, after adjusting on relevant factors. Sixteen GLP-1 RA patients (23.5%) experienced incomplete passage of the VCE through the small intestine, a significantly higher rate compared to three patients in the control group (4.4%) (p<0.01). CONCLUSIONS: GLP-1 RA usage is associated with prolonged gastric transit time and a higher rate of incomplete small bowel evaluation during VCE. Future studies may be crucial for evaluating strategies to mitigate these effects.

The prevalence of impostor phenomenon and its association with burnout amongst urologists.

OBJECTIVES: To characterise the prevalence of impostor phenomenon (IP; tendency for high-achieving individuals to perceive themselves as fraudulent in their successes) amongst attending staff in urology, to identify variables that predict more severe impostorism, and to study the association of IP with burnout. SUBJECTS AND METHODS: A survey composed of the Clance Impostor Phenomenon Scale (CIPS), demographic information, practice details, and burnout levels was e-mailed to urologists via urological subspecialty societies. Survey results were analysed to identify associations between IP severity, survey respondent characteristics, and symptoms of professional burnout. This study was conducted in the United States of America. RESULTS: A total of 614 survey responses were received (response rate 11.0%). In all, 40% (n = 213) of responders reported CIPS scores qualifying as either 'frequent' or 'intense' impostorism (i.e., scores of 61-100). On multivariable analysis, female gender, fewer years in practice (i.e., 0-2 years), and lower academic rank were all independently associated with higher CIPS scores (adjusted P < 0.05). Regarding burnout, 46% of responders reported burnout symptoms. On multivariable analysis, increase in CIPS score was independently associated with higher odds of burnout (odds ratio 1.06, 95% confidence interval 1.04-1.07; P < 0.001). CONCLUSION: Impostor phenomenon is prevalent in the urological community and is experienced more severely in younger and female urologists. IP is also independently associated with burnout. Increased female representation may improve IP amongst our female colleagues. More work is needed to determine strategies that are effective in mitigating feelings of IP and professional burnout amongst urologists, particularly those earlier in their careers.

In vitro delayed response to dihydroartemisinin of malaria parasites infecting sickle cell erythocytes.

BACKGROUND: Decreased efficacy of artemisinin-based combination therapy (ACT) for Plasmodium falciparum malaria has been previously reported in patients with sickle cell disease (SCD). The main purpose of this study was to investigate the in vitro susceptibility of isolates to dihydro-artemisinin (DHA) to provide a hypothesis to explain this treatment failure. METHODS: Isolates were collected from patients attending health centres in Abidjan with uncomplicated P. falciparum malaria. The haemoglobin type has been identified and in vitro drug sensitivity tests were conducted with the ring stage assay and maturation inhibition assay. RESULTS: 134 isolates were obtained. Parasitaemia and haemoglobin levels at inclusion were lower in patients with haemoglobin HbSS and HbSC than in patients with normal HbAA. After ex vivo RSA and drug inhibition assays, the lowest rate of parasitic growth was found with isolates from HbAS red cells. Conversely, a significantly higher survival rate of parasites ranging from 15 to 34% were observed in isolates from HbSS. Isolates with in vitro reduced DHA sensitivity correlate with lower RBC count and haematocrit and higher parasitaemia at inclusion compared to those with isolates with normal DHA sensitivity. However, this decrease of in vitro sensitivity to DHA was not associated with Kelch 13-Propeller gene polymorphism. CONCLUSION: This study highlights an in vitro decreased sensitivity to DHA, for isolates collected from HbSS patients, not related to the Pfkelch13 gene mutations. These results are in line with recent studies pointing out the role of the redox context in the efficacy of the drug. Indeed, SCD red cells harbour a highly different ionic and redox context in comparison with normal red cells. This study offers new insights into the understanding of artemisinin selective pressure on the malaria parasite in the context of haemoglobinopathies in Africa.

Sphingosine 1-phosphate (S1P) receptor modulators as an induction and maintenance therapy for ulcerative colitis: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND AND OBJECTIVE: One sphingosine-1-phosphate (S1P) receptor modulator is approved (ozanimod) and another (etrasimod) is under investigation for the induction and maintenance of remission of ulcerative colitis (UC). We aim to evaluate the efficacy and safety of S1P modulators in patients with active UC. METHODS: We conducted a systematic review and meta-analysis synthesizing randomized controlled trials (RCTs), which were retrieved by systematically searching: PubMed, Web of Science, SCOPUS, and Cochrane through May 13th, 2023. We used the fixed-effect model to pool dichotomous data using risk ratio (RR) with a 95% confidence interval (CI). RESULTS: Five RCTs with a total of 1990 patients were included. S1P receptor modulators were significantly associated with increased clinical response during both the induction (RR 1.71 with 95% CI [1.50, 1.94], P = 0.00001) and maintenance phases (RR 1.89 with 95% CI [1.33, 2.69], P = 0.0004); clinical remission rates during both induction (RR 2.76 with 95% CI [1.88, 4.05], P = 0.00001) and maintenance phases (RR 3.34 with 95% CI [1.41, 7.94], P = 0.006); endoscopic improvement during both induction (RR 2.15 with 95% CI [1.71, 2.70], P = 0.00001) and maintenance phases (RR 2.41 with 95% CI [1.15, 5.05], P = 0.02); and histologic remission during both induction (RR 2.60 with 95% CI [1.89, 3.57] [1.17, 2.10], P = 0.00001) and maintenance phases (RR 2.52 with 95% CI [1.89, 3.37], P = 0.00001). Finally, there was no difference regarding safety outcomes as compared to placebo in both the induction and maintenance phases. CONCLUSION: S1P receptor modulators are effective in inducing and maintaining remission in patients with moderate to severe UC.