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Pancreas injury by partial duct ligation (PDL) activates a healing response, encompassing β‐cell neogenesis and proliferation. Macrophages (MΦs) were recently shown to promote β‐cell proliferation after PDL, but they remain poorly characterized. We assessed myeloid cell diversity and the factors driving myeloid cell dynamics following acute pancreas injury by PDL. In naive and sham‐operated pancreas, the myeloid cell compartment consisted mainly of two distinct tissue‐resident MΦ types, designated MHC‐IIlo and MHC‐IIhi MΦs, the latter being predominant. MHC‐IIlo and MHC‐IIhi pancreas MΦs differed at the molecular level, with MHC‐IIlo MΦs being more M2‐activated. After PDL, there was an early surge of Ly6Chi monocyte infiltration in the pancreas, followed by a transient MHC‐IIlo MΦ peak and ultimately a restoration of the MHC‐IIhi MΦ‐dominated steady‐state equilibrium. These intricate MΦ dynamics in PDL pancreas depended on monocyte recruitment by C‐C chemokine receptor 2 and macrophage‐colony stimulating factor receptor as well as on macrophage‐colony stimulating factor receptor‐dependent local MΦ proliferation. Functionally, MHC‐IIlo MΦs were more angiogenic. We further demonstrated that, at least in C‐C chemokine receptor 2‐KO mice, tissue MΦs, rather than Ly6Chi monocyte‐derived MΦs, contributed to β‐cell proliferation. Together, our study fully characterizes the MΦ subsets in the pancreas and clarifies the complex dynamics of MΦs after PDL injury.  相似文献   
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ObjectivesThe current paper presents firstly the Interpersonal Psychological Theory of Suicide (IPTS) and its interest in the risk of suicide in physicians and/or medical students and secondly an original study on 178 medical students.MethodsIn total, 178 medical students of the Université Libre de Bruxelles filled out an ad hoc questionnaire rating suicidal ideations (life-time), recent suicidal plans and recent suicidal ideations rated by the 9th item of the Beck Depression Inventory-II (BDI). The subjects completed the French version of the Interpersonal Needs Questionnaire (INQ) rating Perceived burdensomeness and Thwarted belongingness and the Acquired Capability for Suicide Scale (ACSS) as well as the Beck Depression Inventory-II (BDI-II). Among the 178 medical students, 95 had no suicide risk, 24 had life-time suicidal ideation, 28 had recent suicidal ideations and 26 had recent suicidal plans. The four groups were compared for gender and age as well as for the different rating scales using Chi2 tests or analyses of variance (ANOVA).ResultsThe four groups had no significant differences for age, gender and scores on the ACSS. ANOVA revealed significant differences for perceived burdensomeness, thwarted belongingness and depression. To control the potential effect of depression, analyses of covariance (ANCOVA) were done taking as covariate a subscale of the BDI-II rating the cognitive component of depression. The two ANCOVA were significant. Post hoc tests comparing two by two the different groups reported that students with recent suicidal ideations or suicidal plans have significantly higher thwarted belongingness than students without suicide risk or students with life time suicidal ideations. Moreover, higher level of perceived burdensomeness was found only in students with suicidal plans comparatively with the three other groups.ConclusionHigh levels of thwarted belongingness and perceived burdensomeness characterize medical students with recent suicidal ideations or suicidal plans independently of the level of depression.  相似文献   
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Prepregnancy overweight and obesity are associated with higher risk of perinatal complications. However, the effect of weight change prior to pregnancy on perinatal outcome is largely unknown. Therefore, it is aimed to examine the impact on perinatal outcomes of interpregnancy BMI change in women of different BMI categories. The MEDLINE, EMBASE, LILACS, and CINAHL databases were searched (1990‐August 2019). Observational studies on interpregnancy BMI change were selected. Outcomes evaluated were gestational diabetes mellitus (GDM), preeclampsia, gestational hypertension (GH), cesarean section, preterm birth, and newborns being large (LGA) or small (SGA) for gestational age. Meta‐analyses and meta‐regression analyses were executed. Thirty studies were included (n > 1 million). Interpregnancy BMI gain was associated with a higher risk of GDM (for BMI gain ≥3 kg/m2: OR 2.21; [95%CI 1.53‐3.19]), preeclampsia (1.77 [1.53‐2.04]), GH (1.78 [1.61‐1.97]), cesarean section (1.32 [1.24‐1.39]), and LGA (1.54 [1.28‐1.86]). The effects of BMI gain were most pronounced in women with BMI <25 kg/m2 before the first pregnancy regarding GDM, GH, and cesarean section. Except for LGA, interpregnancy BMI loss did not result in a decreased risk of perinatal complications. In this study, women of normal weight who gain weight before pregnancy were identified as a high‐risk population for perinatal complications. This emphasizes that weight management is important for women of all BMI categories and a pregnancy wish.  相似文献   
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Toxoplasmosis is a life-threatening infection in immunocompromised patients (ICPs). The definitive diagnosis relies on parasite DNA detection, but little is known about the incidence and burden of disease in HIV-negative patients. A 3-year retrospective study was conducted in 15 reference laboratories from the network of the French National Reference Center for Toxoplasmosis, in order to record the frequency of Toxoplasma gondii DNA detection in ICPs and to review the molecular methods used for diagnosis and the prevention measures implemented in transplant patients. During the study period, of 31,640 PCRs performed on samples from ICPs, 610 were positive (323 patients). Blood (n = 337 samples), cerebrospinal fluid (n = 101 samples), and aqueous humor (n = 100 samples) were more frequently positive. Chemoprophylaxis schemes in transplant patients differed between centers. PCR follow-up of allogeneic hematopoietic stem cell transplant (allo-HSCT) patients was implemented in 8/15 centers. Data from 180 patients (13 centers) were further analyzed regarding clinical setting and outcome. Only 68/180 (38%) patients were HIV+; the remaining 62% consisted of 72 HSCT, 14 solid organ transplant, and 26 miscellaneous immunodeficiency patients. Cerebral toxoplasmosis and disseminated toxoplasmosis were most frequently observed in HIV and transplant patients, respectively. Of 72 allo-HSCT patients with a positive PCR result, 23 were asymptomatic; all were diagnosed in centers performing systematic blood PCR follow-up, and they received specific treatment. Overall survival of allo-HSCT patients at 2 months was better in centers with PCR follow-up than in other centers (P < 0.01). This study provides updated data on the frequency of toxoplasmosis in HIV-negative ICPs and suggests that regular PCR follow-up of allo-HSCT patients could guide preemptive treatment and improve outcome.  相似文献   
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Few studies have been conducted on the effects of air pollution on patients with chronic obstructive pulmonary disease (COPD). During a 14-mo period, 39 Parisian adults with severe COPD were monitored by their physicians. Daily levels of 4 air pollutants were provided by an urban air-quality network. Exacerbation of COPD was associated only with ozone (O3) (odds ratio [OR] = 1.44 for a 10-μg/m3 increase in O3; 95% confidence interval [Cl] = 1.14, 1.82), with a lag of 2-3 days. The effect of O3 was greater in patients whose carbon dioxide pressure (PaCO2) was higher than 43 mm Hg (OR = 1.83; 95% Cl = 1.36, 2.47) vs. those with a lower PaCO2 (OR = 1.26; 95% Cl = 0.90, 1.77). The effect of O3 was unchanged, regardless of the maintenance medications used. The only air pollutant to which patients with severe COPD were particularly sensitive was O3.  相似文献   
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