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31.
Immune activation and cell proliferation may contribute to the development of increased homocysteine concentrations in patients with malignant diseases. In this study, we investigated the effect of interferon-alpha (IFN-alpha) on plasma homocysteine concentrations in patients being treated for malignant melanoma. In parallel, neopterin formation and tryptophan degradation were monitored to assess the capacity of IFN-alpha to activate macrophages. Plasma concentrations of homocysteine, folate, and vitamin B(12) were determined in 15 patients with malignant melanoma during 12 weeks of high-dose IFN-alpha therapy. Concurrently, concentrations of neopterin, tryptophan, and kynurenine were measured, and the kynurenine/tryptophan ratio (kyn/trp) was calculated. Homocysteine and folate concentrations during treatment with IFN-alpha did not differ from baseline. In contrast, significant increases in neopterin formation and tryptophan degradation were apparent during IFN-alpha therapy. Plasma concentrations of vitamin B(12) and cysteine also increased. These results indicate that IFN-alpha directly activates macrophages to release neopterin and to degrade tryptophan, but obviously treatment with INF-alpha did not affect homocysteine metabolism.  相似文献   
32.
Neural stem cells (NSCs) are slowly dividing astrocytes that are intimately associated with capillary endothelial cells in the subventricular zone (SVZ) of the brain. Functionally, members of the vascular endothelial growth factor (VEGF) family can stimulate neurogenesis as well as angiogenesis, but it has been unclear whether they act directly via VEGF receptors (VEGFRs) expressed by neural cells, or indirectly via the release of growth factors from angiogenic capillaries. Here, we show that VEGFR-3, a receptor required for lymphangiogenesis, is expressed by NSCs and is directly required for neurogenesis. Vegfr3:YFP reporter mice show VEGFR-3 expression in multipotent NSCs, which are capable of self-renewal and are activated by the VEGFR-3 ligand VEGF-C in vitro. Overexpression of VEGF-C stimulates VEGFR-3-expressing NSCs and neurogenesis in the SVZ without affecting angiogenesis. Conversely, conditional deletion of Vegfr3 in neural cells, inducible deletion in subventricular astrocytes, and blocking of VEGFR-3 signaling with antibodies reduce SVZ neurogenesis. Therefore, VEGF-C/VEGFR-3 signaling acts directly on NSCs and regulates adult neurogenesis, opening potential approaches for treatment of neurodegenerative diseases.  相似文献   
33.
BackgroundWomen who engage in higher levels of exercise while trying to quit smoking have been shown to be less likely to relapse and to sustain their smoking abstinence longer. This study sought to examine the benefits of exercise for improving smoking cessation among Black women.MethodsWe evaluated the feasibility of a 12-week smoking and exercise intervention, Quit and Fit, tailored for Black women. All participants (intervention and control) received 12 weeks of smoking cessation counseling via telephone and 9 weeks of nicotine lozenges. Participants who were randomly assigned to the intervention condition were also assigned to a 12-week exercise group.ResultsThirty-eight women were enrolled and 27 completed a 12-week follow-up assessment. Women from the intervention group were more likely to complete the 12-week follow-up assessment compared to participants in the control group (80% vs. 61%). Overall, 7 of the 38 participants (18%) were abstinent at 12 weeks (biochemically verified by expired carbon monoxide). Among the 25 women who completed the 12-week follow-up, abstinence was reported in 33% of the intervention group and 20% of the control group. Using an intent-to-treat approach, 25% of women in the intervention group were abstinent at 12 weeks (n = 5), compared to 11.1% for the control group (n = 2). These differences were not statistically significant.ConclusionsThe overall retention rate was 71% (27/38) at 12 weeks with higher among the intervention group (16/20; 80%) compared to the control group (11/18; 61%). The study demonstrates that it is feasible to retain African-American women in a short-term study of smoking cessation and exercise.  相似文献   
34.
Bone marrow progenitors migrate to the thymus, where they proliferate and differentiate into immunologically competent T cells. In this report we show that mice transgenic for SV40 T and t antigens under the control of the L-pyruvate kinase promoter develop, in a first step, thymic hyperplasia of both thymocytes and epithelial cells. Morphological studies (histology, immunohistolabeling and electron microscopy) revealed modifications of the thymic microenvironment and gradual expansion of medullary epithelial cells in 1 month-old mice, taking over the cortical region. Then, a thymic carcinoma develops. Two-color labeling of frozen sections identified the transgene in medullary epithelial cells. Flow cytometry analysis demonstrated a marked increase in mature CD4+ and CD8+ thymocytes in adult mice (39 +/- 10 x 10(6) in transgenic mice and 12 +/- 5 x 10(6) in age-matched controls). Furthermore, thymocyte export was disturbed.  相似文献   
35.
36.
Mandibulofacial dysostosis, Guion‐Almeida type (MFDGA) is a recently delineated multiple congenital anomalies/mental retardation syndrome characterized by the association of mandibulofacial dysostosis (MFD) with external ear malformations, hearing loss, cleft palate, choanal atresia, microcephaly, intellectual disability, oesophageal atresia (OA), congenital heart defects (CHDs), and radial ray defects. MFDGA emerges as a clinically recognizable entity, long underdiagnosed due to highly variable presentations. The main differential diagnoses are CHARGE and Feingold syndromes, oculoauriculovertebral spectrum, and other MFDs. EFTUD2, located on 17q21.31, encodes a component of the major spliceosome and is disease causing in MFDGA, due to heterozygous loss‐of‐function (LoF) mutations. Here, we describe a series of 36 cases of MFDGA, including 24 previously unreported cases, and we review the literature in order to delineate the clinical spectrum ascribed to EFTUD2 LoF. MFD, external ear anomalies, and intellectual deficiency occur at a higher frequency than microcephaly. We characterize the evolution of the facial gestalt at different ages and describe novel renal and cerebral malformations. The most frequent extracranial malformation in this series is OA, followed by CHDs and skeletal abnormalities. MFDGA is probably more frequent than other syndromic MFDs such as Nager or Miller syndromes. Although the wide spectrum of malformations complicates diagnosis, characteristic facial features provide a useful handle.  相似文献   
37.
Clémence Jacquin  Emilie Landais  Céline Poirsier  Alexandra Afenjar  Ahmad Akhavi  Nathalie Bednarek  Caroline Bénech  Adeline Bonnard  Damien Bosquet  Lydie Burglen  Patrick Callier  Sandra Chantot-Bastaraud  Christine Coubes  Charles Coutton  Bruno Delobel  Margaux Descharmes  Jean-Michel Dupont  Vincent Gatinois  Nicolas Gruchy  Sarah Guterman  Abdelkader Heddar  Lucas Herissant  Delphine Heron  Bertrand Isidor  Pauline Jaeger  Guillaume Jouret  Boris Keren  Paul Kuentz  Cedric Le Caignec  Jonathan Levy  Nathalie Lopez  Zoe Manssens  Dominique Martin-Coignard  Isabelle Marey  Cyril Mignot  Chantal Missirian  Céline Pebrel-Richard  Lucile Pinson  Jacques Puechberty  Sylvia Redon  Damien Sanlaville  Marta Spodenkiewicz  Anne-Claude Tabet  Alain Verloes  Gaelle Vieville  Catherine Yardin  François Vialard  Martine Doco-Fenzy 《American journal of medical genetics. Part A》2023,191(2):445-458
Chromosome 1p36 deletion syndrome (1p36DS) is one of the most common terminal deletion syndromes (incidence between 1/5000 and 1/10,000 live births in the American population), due to a heterozygous deletion of part of the short arm of chromosome 1. The 1p36DS is characterized by typical craniofacial features, developmental delay/intellectual disability, hypotonia, epilepsy, cardiomyopathy/congenital heart defect, brain abnormalities, hearing loss, eyes/vision problem, and short stature. The aim of our study was to (1) evaluate the incidence of the 1p36DS in the French population compared to 22q11.2 deletion syndrome and trisomy 21; (2) review the postnatal phenotype related to microarray data, compared to previously publish prenatal data. Thanks to a collaboration with the ACLF (Association des Cytogénéticiens de Langue Française), we have collected data of 86 patients constituting, to the best of our knowledge, the second-largest cohort of 1p36DS patients in the literature. We estimated an average of at least 10 cases per year in France. 1p36DS seems to be much less frequent than 22q11.2 deletion syndrome and trisomy 21. Patients presented mainly dysmorphism, microcephaly, developmental delay/intellectual disability, hypotonia, epilepsy, brain malformations, behavioral disorders, cardiomyopathy, or cardiovascular malformations and, pre and/or postnatal growth retardation. Cardiac abnormalities, brain malformations, and epilepsy were more frequent in distal deletions, whereas microcephaly was more common in proximal deletions. Mapping and genotype–phenotype correlation allowed us to identify four critical regions responsible for intellectual disability. This study highlights some phenotypic variability, according to the deletion position, and helps to refine the phenotype of 1p36DS, allowing improved management and follow-up of patients.  相似文献   
38.
The origins of cerebral abnormalities in psychotic patients remain unknown. Dermatoglyphics are suitable markers of prenatal injury due to their fetal ontogenesis and their susceptibility to some of the factors that also affect cerebral development. In a previous study, positive associations between brain volumetric measures and a dermatoglyphic marker, the ab-ridge count, were reported. The present study is an attempt to replicate that finding in an independent sample. Magnetic resonance imaging (MRI) scans and dermatoglyphic measures were available for 29 schizophrenia patients (Research Diagnostic Criteria [RDC] criteria) and 26 unrelated healthy controls. The images were processed using an automated procedure, yielding volumes of total grey matter, white matter, cerebrospinal fluid (CSF), and total brain volume. The ab-ridge count was not positively associated with brain volumes in either patients or controls. The present findings do not support the hypothesis that the changes in brain volume seen in patients with schizophrenia are of prenatal origin.  相似文献   
39.
Feeding legume grains to pigs usually increases losses of endogenous proteins at the terminal ileum. However, the identity of such proteins is largely unknown. This study was undertaken to determine the ileal flow and identity of soluble proteins present in large concentrations in ileal digesta of young pigs fed soybean meal (SBM), peas (P), faba beans (FB), or blue lupin (L) in expt. 1, and white (WPC) or black (BPC) chickpeas in expt. 2. Protein in the control diet (C) was provided by casein. Ileal digesta proteins were analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis, Coomassie blue staining, densitometry and N-terminal amino acid sequencing. Three protein bands at molecular masses of 25, 27, and 30 kDa had a higher ileal flow (P < 0.05) in the pigs fed the legume-based diets compared to those fed the control diet in expt. 2. This was true for the 25- and 30-kDa proteins (P < 0.05) and the 27-kDa protein (P < 0.10) in pigs fed the legume-containing diets in expt. 1. These proteins shared N-terminal amino acid sequences with enzymes of the serine protease family including pig trypsin (25 kDa) and blood coagulation factor IX or chymotrypsin (27 and 30 kDa).  相似文献   
40.
Treatment of cytokine-induced depression   总被引:5,自引:0,他引:5  
A high proportion of cancer and hepatitis C patients who receive cytokine immunotherapy develop symptoms of depression that are indistinguishable from those found in major depressive disorders. These symptoms are alleviated by anti-depressant treatment. Moreover, preventive treatment with anti-depressants, in particular selective serotonin reuptake inhibitors (SSRIs) attenuates IFN-alpha-associated symptoms of depression, anxiety, and neurotoxicity. The intermediate mechanisms of these effects are still unclear. Studies suggest that the state of depression is associated with an increase in plasma levels of various cytokines and soluble cytokine receptors. Furthermore, anti-depressants have been shown to shift the cytokine network towards a decreased production of pro-inflammatory cytokines and an increased production of anti-inflammatory cytokines. Other studies suggest that anti-depressants can also modify immune reactivity by acting on neural structures involved in neuroimmunomodulation. It is possible that anti-depressants could help to normalize the serotoninergic neurotransmission that is likely disrupted during immunotherapy due to the potent effects of cytokines on the metabolism of the amino acid precursor tryptophan. Further work is needed to optimize strategies for preventing neuropsychiatric side effects of cytokine immunotherapy, to clarify the mechanisms involved in the alleviating effects of anti-depressants on cytokine-induced depression, as well as to assess the possible consequences of anti-depressant therapy on the efficacy of immunotherapy on the disease process.  相似文献   
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