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41.
Aging is accompanied by many physiological changes including those in the immune system. These changes are designated as immunosenescence indicating that age induces a decrease in immune functions. However, since many years we know that some aspects are not decreasing but instead are increasing like the pro-inflammatory activity by the innate immune cells, especially by monocytes/macrophages. Recently it became evident that these cells may possess a sort of memory called trained memory sustained by epigenetic changes occurring long after even in the absence of the initiator aggressor. In this review we are reviewing evidences that such changes may occur in aging and describe the relationship between inflamm-aging and immunosenescence as an adaptation/remodelling process leading on one hand to increased inflammation and on the other to decreased immune response (immune-paralysis) mastered by the innate immune system. These changes may collectively induce a state of alertness which assure an immune response even if ultimately resulting in age-related deleterious inflammatory diseases.  相似文献   
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Twenty-four cases of anomalous origin of the left coronary artery from the pulmonary artery are reported. These cases were collected over 27 years divided into three 9-year periods according to the years of the initial studies. The clinical aspects and diagnostic investigations (notably echocardiography, myocardial radioisotope imaging and various angiographic procedures) are reviewed; aortography seems to be, even now, the best exploratory method. Treatment is analyzed according to the periods of observations. From the earliest cases it may be concluded that ligation proved ineffective in infants and medical treatment often failed. Progressively, medical treatment with digitalis (now better controlled), potassium-sparing diuretics and vasodilators has become more effective. On the other hand, direct reimplantation of the left coronary artery onto the aorta has become the preferred surgical procedure. Among the 8 most recent cases (seen between 1977 and 1986), 4 were cured by medical treatment under the age of 3 and subsequent reimplantation. In the other 4 patients asystolia responded to medical treatment, and these children are now awaiting reimplantation.  相似文献   
44.
The authors report 9 cases of atrial septal defect with sever pulmonary hypertension in 7 girls and 2 boys under 10 years of age. These cases represent 3.5% of the 255 cases of atrial septal defect in this age group seen at the Hopital Cardiologique of Lille between 1970 and 1985. Group I comprised 3 children with obstructive pulmonary hypertension from the start; two died, one is still alive after 3 years. Group II was composed of 3 children who presented, at first haemodynamic evaluation, with severe but non-obstructive pulmonary hypertension; the hypertension rapidly became obstructive in 2 of them despite digitalis-diuretic therapy; the third child died after surgical correction. The 3 children in group III had normal or slightly raised pulmonary arterial pressure at first haemodynamic evaluation; one of them initially had a right ventricle-pulmonary artery functional gradient of 45 mmHg, which did not prevent the subsequent development of obstructive pulmonary hypertension; the other 2 patients were operated upon 10 months and 4 years later respectively, as they presented with severe pulmonary hypertension; one of these 2 children died postoperatively, the third one developed obstructive pulmonary hypertension. Contrary to what is generally believed, severe pulmonary hypertension is not exceptional in children with atrial septal defect, and it has a poor prognosis. The mechanism underlying the development of this pulmonary hypertension is unclear, but individual susceptibility to excessive blood flow is probable, as is the role played by bronchopulmonary infections frequently noted in these patients' history.  相似文献   
45.
The Nogo-66 receptor (NgR) plays a critical role in restricting axon regeneration in the central nervous system. This inhibitory action is in part mediated by a neuronal receptor complex containing p75NTR, a multifunctional receptor also well known to trigger cell death upon binding to neurotrophins such as NGF. In the present study, we show that Pep4 and NEP1-40, which are two peptides derived from the Nogo-66 sequence that modulate NgR-mediated neurite outgrowth inhibition, prevent NGF-stimulated p75NTR-dependent death of cultured embryonic motor neurons. They also confer protection on spinal cord motor neurons after neonatal sciatic nerve axotomy. These findings demonstrate an as-yet-unknown function of NgR in maintaining neuronal survival that may be relevant for motor neuron development and degeneration.  相似文献   
46.
Pf 51 cases of Fallot's tetralogy who underwent preoperative angiography before a palliative anastomosis and then a second angiography before complete correction, 10 had developed pulmonary atresia (infundibular in 8 cases, valvular in 2 cases). The type of anastomosis (Blalock-Taussig of Waterston), and the interval between the two operations do not seem to be determinant factors. The initial severity of the stenosis seems to favour the development of atresia but this is not invariable. The authors discuss the aggravating role of the anastomosis and the consequences of this type of complication.  相似文献   
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A large, multicentre, retrospective survey of patients with hairy cell leukaemia (HCL) was conducted in France to determine the frequency of second malignancies and to analyse the long‐term effects of the established purine nucleoside analogues (PNAs), cladribine and pentostatin. The survey retrospectively reviewed the medical history of patients and their immediate family, clinical and biological presentation at the time of HCL diagnosis, treatment choice, response to treatment, time to relapse and cause of death. Data were collected for 487 patients with HCL. Of the patients included in the survey, 18% (88/487) had a familial history of cancers, 8% (41/487) presented with malignancies before HCL diagnosis and 10% (48/487) developed second malignancies after HCL was diagnosed. An excess incidence of second malignancies was observed, with a standardized incidence ratio (SIR) of 1·86 (95% confidence interval (CI): 1·34–2·51), with no significant difference between PNAs. For second haematological malignancies alone, the SIR was markedly increased at 5·32 (95% CI: 2·90–8·92). This study highlights the high frequency of cancers in HCL patients and their family members. The frequency of second malignancies is notably increased, particularly for haematological malignancies. The respective role of pentostatin and cladribine in the development of second malignancies is debatable.  相似文献   
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Type 2 diabetes (T2D) disproportionally affects African Americans (AfA) but, to date, genetic variants identified from genome-wide association studies (GWAS) are primarily from European and Asian populations. We examined the single nucleotide polymorphism (SNP) and locus transferability of 40 reported T2D loci in six AfA GWAS consisting of 2,806 T2D case subjects with or without end-stage renal disease and 4,265 control subjects from the Candidate Gene Association Resource Plus Study. Our results revealed that seven index SNPs at the TCF7L2, KLF14, KCNQ1, ADCY5, CDKAL1, JAZF1, and GCKR loci were significantly associated with T2D (P < 0.05). The strongest association was observed at TCF7L2 rs7903146 (odds ratio [OR] 1.30; P = 6.86 × 10−8). Locus-wide analysis demonstrated significant associations (Pemp < 0.05) at regional best SNPs in the TCF7L2, KLF14, and HMGA2 loci as well as suggestive signals in KCNQ1 after correction for the effective number of SNPs at each locus. Of these loci, the regional best SNPs were in differential linkage disequilibrium (LD) with the index and adjacent SNPs. Our findings suggest that some loci discovered in prior reports affect T2D susceptibility in AfA with similar effect sizes. The reduced and differential LD pattern in AfA compared with European and Asian populations may facilitate fine mapping of causal variants at loci shared across populations.Type 2 diabetes (T2D) is a major public health problem affecting 25.8 million people in the U.S. (1). Marked racial differences in its prevalence have been observed, with African American (AfA) adults >40 years of age having nearly twofold higher prevalence than European Americans (27.1 and 15.5%, respectively) (2). In addition to socioeconomic and behavioral risk factors, genetic factors are likely contributors to T2D risk in AfA (3).Genome-wide association studies (GWAS) for T2D and related traits have successfully identified >50 loci with common genetic variants associated with T2D risk in primarily European-descent populations (414) and more recently in East and South Asians (1521). The reported index single nucleotide polymorphisms (SNPs) at these loci have been replicated in multiple populations (2224) but less successfully in AfA (2527). Although differences in environment and lack of study power may partly account for the lack of transferability across ethnicities, differences in linkage disequilibrium (LD) patterns, effect sizes, and risk allele frequency also likely impact the replication of index SNPs. Although the long-range LD in European populations allows for the identification of T2D loci using less dense markers, causal variants are not distinguishable from other nearby SNPs in high LD. This issue prompts the need to examine T2D loci in other populations with different allelic and LD architecture, which may help fine mapping of the underlying functional variants (28).We performed a comprehensive evaluation of the LD region of T2D loci reported in European and Asian GWAS in a meta-analysis of six AfA GWAS. By testing the index and nearby SNPs, we evaluated the transferability of the previously reported loci for T2D association in AfA. We demonstrated that the reduced and differential LD structure in AfA facilitated fine mapping of regions potentially harboring causal variants at some T2D loci.  相似文献   
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