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61.
Data from uniparentally inherited genetic systems were used to trace evolution of human populations. Reconstruction of the past primarily relies on variation in present-day populations, limiting historical inference to lineages that are found among living subjects. Our analysis of four population groups in the Gaspé Peninsula, demonstrates how this may occasionally lead to erroneous interpretations. Mitochondrial DNA analysis of Gaspesians revealed an important admixture with Native Americans. The most likely scenario links this admixture to French-Canadians from the St. Lawrence Valley who moved to Gaspesia in the 19th century. However, in contrast to genetic data, analysis of genealogical record shows that Native American maternal lineages were brought to Gaspesia in the 18th century by Acadians who settled on the south-western coast of the peninsula. Intriguingly, within three generations, virtually all Métis Acadian families separated from their nonadmixed relatives and moved eastward mixing in with other Gaspesian groups, in which Native American maternal lines are present in relatively high frequencies. Over time, the carriers of these lines eventually lost memory of their mixed Amerindian-Acadian origin. Our results show that a reliable reconstruction of population history requires cross-verification of different data sources for consistency, thus favouring multidisciplinary approaches.  相似文献   
62.
Diabetic retinopathy is associated with ocular inflammation, leading to retinal barrier breakdown, macular edema, and visual cell loss. We investigated the molecular mechanisms involved in microglia/macrophages trafficking in the retina and the role of protein kinase Cζ (PKCζ) in this process. Goto Kakizaki (GK) rats, a model for spontaneous type 2 diabetes were studied until 12 months of hyperglycemia. Up to 5 months, sparse microglia/macrophages were detected in the subretinal space, together with numerous pores in retinal pigment epithelial (RPE) cells, allowing inflammatory cell traffic between the retina and choroid. Intercellular adhesion molecule-1 (ICAM-1), caveolin-1 (CAV-1), and PKCζ were identified at the pore border. At 12 months of hyperglycemia, the significant reduction of pores density in RPE cell layer was associated with microglia/macrophages accumulation in the subretinal space together with vacuolization of RPE cells and disorganization of photoreceptors outer segments. The intraocular injection of a PKCζ inhibitor at 12 months reduced iNOS expression in microglia/macrophages and inhibited their migration through the retina, preventing their subretinal accumulation. We show here that a physiological transcellular pathway takes place through RPE cells and contributes to microglia/macrophages retinal trafficking. Chronic hyperglycemia causes alteration of this pathway and subsequent subretinal accumulation of activated microglia/macrophages.  相似文献   
63.
Contaminated mud and soil may play roles as reservoirs and sources of transmission for avian influenza A virus. However, the persistence of highly pathogenic avian influenza (HPAI) H5N1 virus in soil or mud has not been well documented, and specific methods of H5N1 virus detection in mud and soil specimens have not been described. The aim of this work was to evaluate the capacities of five different commercial kits and one elution-concentration technique to extract nucleic acids from H5N1 virus and to detect infectious viral particles in experimentally infected mud specimens. The viral RNA detection thresholds for the QIAamp kit, Trizol LS and the MagNA Pure LC kit were 5 × 10(2)RNA copies per gram of mud. Trizol reagent and the RNA PowerSoil? kit were unsuccessful in recovering any viral RNA from mud. When the elution-concentration technique was performed prior to nucleic acid extraction, the performance of the MagNA Pure kit increased to a level that allowed the detection of H5N1 nucleic acids in naturally contaminated environmental samples that had previously tested negative after direct extraction using commercial kits. The levels of detection of infectious virus after inoculation into embryonated eggs were higher in concentrates than in eluates.  相似文献   
64.
This guideline advises on the management of patients with egg allergy. Most commonly egg allergy presents in infancy, with a prevalence of approximately 2% in children and 0.1% in adults. A clear clinical history will confirm the diagnosis in most cases. Investigation by measuring egg-specific IgE (by skin prick testing or specific IgE assay) is useful in moderate-severe cases or where there is diagnostic uncertainty. Following an acute allergic reaction, egg avoidance advice should be provided. Egg allergy usually resolves, and reintroduction can be achieved at home if reactions have been mild and there is no asthma. Patients with a history of severe reactions or asthma should have reintroduction guided by a specialist. All children with egg allergy should receive the MMR vaccine. Most adults and children with egg allergy can receive the influenza vaccine in primary care, unless they have had anaphylaxis to egg requiring intensive care support. Yellow Fever vaccines should only be considered in egg-allergic patients under the guidance of an allergy specialist. This guideline was prepared by the Standards of Care Committee (SOCC) of the British Society for Allergy and Clinical Immunology (BSACI) and is intended for allergists and others with a special interest in allergy. The recommendations are evidence based. Where evidence was lacking, consensus was reached by the panel of specialists on the committee. The document encompasses epidemiology, risk factors, diagnosis, treatment, prognosis and co-morbid associations.  相似文献   
65.
BACKGROUND: Primary care physicians are potentially important sources of interventions aimed at preventing youth smoking. Yet recent surveys suggest that physician smoking prevention practices are less than optimal. OBJECTIVES: To document prevention counseling practices and to identify correlates of these activities in a random sample of general practitioners in Montreal, Quebec. METHODS: A cross-sectional mail survey. RESULTS: Of 440 eligible general practitioners (GPs), 337 (77%) completed the questionnaire. General practitioners were more likely to ascertain the smoking status of adolescents (70.9%) than preadolescents (35.7%). Although about half of the GPs offered advice to prevent smoking onset in young adults (48.6%) and adolescents (48.3%), fewer did so for preadolescents (34.4%); only 12.1% advised parents to discuss smoking onset with their children. Correlates of ascertaining smoking status included female sex (odds ratio [OR], 1.90; 95% confidence interval [CI], 1.07-3.41), lower proportion of walk-in patients (OR, 2.73; 95% CI, 1.31-5.80), awareness of the "stage of behavior change" model (OR, 2.17; 95% CI, 1.18-4.04), and higher self-efficacy (OR, 4.12, 95% CI, 2.00-8.69). Correlates of provision of prevention advice included more hours spent in direct patient care (OR, 1.93; 95% CI, 1.13-3.34), favorable beliefs and attitudes (OR, 1.73; 95% CI, 1.06-2.83), and higher self-efficacy (OR, 4.32; 95% CI, 2.25-8.44). CONCLUSIONS: Our results point to the need for renewed efforts to enhance preventive efforts in primary care settings. Intervention programs for GPs should emphasize overcoming unfavorable beliefs and attitudes and low self-efficacy. Future research should evaluate the effect of brief prevention counseling adapted to increasingly busy practices.  相似文献   
66.
A 53-year-old-woman presenting with pelvic discomfort was found to have a 9.5 cm tumor located in the wall of the ileon. Light microscopy showed that the tumor was made of fascicles of plump spindle cells and bizarre epithelioid cells. A cuff of lymphoid cells was also present at the tumor margin. The tumor cells strongly expressed tau protein, neuron-specific enolase, protein green product 9.5 and glial fibrillary acid protein (GFAP), but did not show positive immunostaining for S-100 protein, CD34 or CD117. The tumor showed unequivocal ultrastructural evidence of neural differentiation. Skeinoid fibers were scattered throughout the tumor. This is the first mixed neuronal-glial tumor of the digestive tract to be described in the literature. Such histological and immunohistochemical features could be misinterpreted as features of digestive schwannoma. We suggest that this tumor is distinct from gastrointestinal stromal tumors in lacking CD34 and CD117 expression.  相似文献   
67.
Superoxide anion (O2°-)production by neutrophil NADPH oxidase participates in arthritic joint lesion formation. Proinflammatory cytokines such as tumor necrosis factor (TNF), interleukin 8 (IL-8) and granulocyte/macrophage-colony stimulating factor (GM-CSF) have a priming effect on neutrophil NADPH oxidase activity. NADPH oxidase activation is dependent on phosphorylation of p47phox, a cytosolic component of the enzyme. We studied O2°-production and p47phox phosphorylation in synovial fluid (SF) from patients with rheumatoid arthritis (RA) and spondylarthropathy (SpA) according to TNF, IL-8 and GM-CSF levels. O2°-production by neutrophils isolated from SF of all the arthritis patients (RA and SpA) was higher than that of circulating resting neutrophils and when stimulated with fMLP or PMA. In addition, p47phox was partially phosphorylated in SF neutrophils compared to circulating neutrophils. High levels of TNF and IL-8 (but not GM-CSF) are detected in patient's SF (compared to circulating blood levels). TNF levels were significantly higher in RA than in SpA SF. These results suggest that increased NADPH oxidase activity could be involved in arthritic joint inflammation through increased p47phox phosphorylation. This could be the result of the presence of high levels of priming agents such as TNF and IL-8 but not GM-CSF.  相似文献   
68.
Neutrophils constitute the first line of cellular defense against pathogens and autophagy is a fundamental cellular homeostasis pathway that operates with the intracellular degradation/recycling system. Induction of the autophagic process in neutrophils, in response to invading pathogens, constitutes a crucial mechanism in innate immunity. Exploration of autophagy has greatly progressed and diverse strategies have been reported for studying this molecular process in different biological systems; especially in infectious and inflammatory diseases. Furthermore, the role of autophagy in neutrophils, during pathogenic infection, continues to be of interest, due to the role of the cell in immunity function, its recruitment to the site of infection and its implication in inflammatory diseases. This review focuses on the known role of autophagy in neutrophils defence against pathogenic infections. A more detailed discussion will concern the recent findings highlighting the role of autophagy in inflammation and cell death in infected neutrophils.  相似文献   
69.
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   
70.
Stormorken syndrome is a rare autosomal dominant disorder characterized by a phenotype that includes miosis, thrombocytopenia/thrombocytopathy with bleeding time diathesis, intellectual disability, mild hypocalcemia, muscle fatigue, asplenia, and ichthyosis. Using targeted sequencing and whole‐exome sequencing, we identified the c.910C > T transition in a STIM1 allele (p.R304W) only in patients and not in their unaffected family members. STIM1 encodes stromal interaction molecule 1 protein (STIM1), which is a finely tuned endoplasmic reticulum Ca2+ sensor. The effect of the mutation on the structure of STIM1 was investigated by molecular modeling, and its effect on function was explored by calcium imaging experiments. Results obtained from calcium imaging experiments using transfected cells together with fibroblasts from one patient are in agreement with impairment of calcium homeostasis. We show that the STIM1 p.R304W variant may affect the conformation of the inhibitory helix and unlock the inhibitory state of STIM1. The p.R304W mutation causes a gain of function effect associated with an increase in both resting Ca2+ levels and store‐operated calcium entry. Our study provides evidence that Stormorken syndrome may result from a single‐gene defect, which is consistent with Mendelian‐dominant inheritance.  相似文献   
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