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1.
The authors studied the sensitivity and specificity of several epidural test doses as markers of intravascular injection in laboring patients in a prospective double-blind, randomized study. Fifty-nine parturients were assigned randomly to receive an intravenous injection of either normal saline solution (3 mL, NS group) or 1.5% lidocaine with epinephrine 1:200,000 (1 mL, EPI-5 group; 2 mL, EPI-10 group; or 3 mL, EPI-15 group). The EPI-5 and EPI-10 doses were diluted to 3 mL volume with normal saline solution. All injections were given during uterine diastole. Maternal heart rate was monitored with a pulse oximeter. An observer who was unaware of the study treatment recorded the baseline and the peak maternal heart rate within the first minute after the injection and questioned the patient about tinnitus, dizziness, metallic taste, and palpitations. He then recorded his opinion as to whether the patient had received the saline or the test solution. Analysis of the maternal heart rate showed an average increase (baseline-to-peak criterion) of 8 +/- 10 beats/min (mean +/- SD) in the NS group. In the other groups, the increase was 21 +/- 8 (EPI-5 group), 31.5 +/- 13 (EPI-10 group), and 29 +/- 9 beats/min (EPI-15 group). A baseline-to-peak criterion of greater than 10 beats/min identified all intravascular injections in the EPI-15 (by design) and EPI-10 groups (15 of 15 and 14 of 14, respectively) with a sensitivity of 100%. Specificity was 73% (11 of 15 true negatives).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Adhesion of circulating cells to the arterial surface is among the first detectable events in atherogenesis. Cellular adhesion molecules, expressed by the vascular endothelium and by circulating leucocytes, mediate cell recruitment and their transendothelial migration. Platelet endothelial cellular adhesion molecule 1 (PECAM-1/CD31), involved in this migration, has been associated with the developmental course of atherosclerosis. A few studies have investigated an association between coronary heart disease and single nucleotide polymorphisms (SNPs) located in functionally important domains of the PECAM-1/CD31 gene. In particular, Ser563Asn and Gly670Arg SNPs have been described as susceptibility factors involved in acute myocardial infarction (AMI) in the Japanese male population. To confirm these observations, we studied 96 male patients (mean age 40 years; age range 20-46) affected by AMI and 118 healthy male controls (mean age 38 years, age range: 20-55), and analysed for the following PECAM-1/CD31 SNPs: Val125Leu, Asn563Ser and Gly670Arg. The frequency of the Gly670Arg polymorphism was significantly higher in patients with AMI (58.9% vs. 48.3%; P = 0.019), whereas the frequencies of the other two SNPs (Leu125Val and Ser563Asn) were not significantly different between patients and controls. By comparing the observed number of 670Arg/Arg genotypes in the patients with the expected number, calculated from the allele frequency in a healthy population, a significance of P = 0.02 (odds ratio, 2.04; 95% CI: 1.1-3.7) was obtained, supporting a recessive model of inheritance. Hence, the differences between patients and controls are significant, but relatively small. However, as AMI is a multifactorial disease, any single mutation will only provide a small or modest contribution to the risk, which also depends on environmental interaction. All in all, we believe that the results of the present study would add support to the role of pro/anti-inflammatory genotypes in determining susceptibility or resistance to immune-inflammatory diseases, including atherosclerosis.  相似文献   
3.
Genetic hemochromatosis is an autosomal recessive disorder characterized by iron overload and a variety of clinical manifestations such as liver cirrhosis and arthropathy. It is the most common genetic disease of northern European populations. The principal gene responsible for hereditary hemochromatosis, designated HFE, is located on chromosome 6 in the HLA region. The single point mutation 845A, changing cysteine at position 282 to tyrosine (C282Y), in this gene has been identified as the main genetic basis of hereditary hemochromatosis. Two other mutations, 187G, a histidine to aspartate at amino acid 63 (H63D), and 193T, a serine to cysteine at amino acid 65 (S65C), appear to be associated with milder forms of hereditary hemochromatosis. There is a high prevalence of the C282Y mutation in northern European populations, whereas in those of the Mediterranean basin the prevalence seems low and almost absent in Far East countries. This mutation seems usually to occur on the ancestral haplotype 7.1. Accordingly, a Celtic origin of this mutation has been suggested. The aim of this study was to determine the frequency of HFE gene mutations in five geographic regions in Italy. Samples were tested for C282Y, H63D, and S65C mutations of the HFE gene according to methods of each laboratory and the results were standardized with the exchange of typed samples between the different laboratories. In addition, C282Y-positive DNA samples were typed for D6S105 allele 8 and HLA-A3 by ARMS-PCR. We have found that the allele frequency of the C282Y mutation decreases from northeast Italy (Friuli, 6%) to northwest Italy (Piedmont, 4.8%) and to central Italy (Emilia-Romagna, 1.7%). However, this mutation is lacking in the two regions of the Mediterranean basin's center (Sicily and Sardinia). Accordingly, a significant difference in the frequency of the mutation was observed between these Italian regions (P = 0.07 x 10(-3)). In contrast, no difference was observed in allele frequency of H63D in the five Italian regions. Finally, as regards the S65C mutation a very low frequency was observed in Friuli, Emilia-Romagna, and Sardinia, whereas in Sicily and Piedmont we have not found this mutation. In conclusion, these data are consistent with the hypothesis that the C282Y mutation occurred in Caucasian populations of Celtic origin, whereas the H63D mutation is more ancient as demonstrated by the ubiquitous distribution.  相似文献   
4.
Gamma/delta T lymphocytes cells recognize the antigen in a non-classical way and are considered the third branch of the immune system devoted to defend the integrity of the body. Ageing is characterized by an impairment of the main way of protection (the adaptive branch) but, successfully aged people show compensatory mechanisms of defense such as proneness to inflammation. Moreover, very old subjects show an increased number of NK cells. We have previously demonstrated that gamma delta T lymphocytes are reduced in elderly. In the present paper we have studied some characteristics of these cells to evaluate the possibility that these cells might balance the decreased action of the adaptive branch in successfully aged people. Cytofluorimetric analysis of cells collected from young, old and centenarian subjects has been used to evaluate the ability of these cells to expand in vitro. Here we demonstrate that gamma delta T cells are impaired in the ability to proliferate to different stimuli such as isopentenyl pyrophoshate, that select gamma delta T lymphocytes bearing delta 2 chain, other than to phytohemagglutinin and anti-CD3 that are polyclonal activators. Moreover, we demonstrate that gamma delta T cells in aged and centenarians show an enhanced sensitivity to undergo apoptosis induced both by alpha-Fas and TNF-alpha. All together these data suggest that gamma delta T lymphocytes are impaired in elderly and suggest that the reduced ability to proliferate and the reduced number of circulating gamma delta T lymphocytes is due to the proneness to apoptosis. Finally on the basis of these data, we conclude that gamma delta T lymphocytes, do not participate in the remodeling of the immune system due to the reduction of classical T cell response and replacement by NK cells in elderly.  相似文献   
5.
Human longevity seems to be directly correlated with optimal functioning of the immune system, suggesting that some genetic determinants of longevity might reside in those polymorphisms for the immune system genes that regulate immune responses, in particular cytokine gene polymorphisms. In fact, modification of cytokine network is a constant report in studies on age related modification of immune response. Moreover cytokine polymorphisms studies are indicating their involvement in the reshaping of cytokines network as an integral part of the scenario related to a successful ageing. A particular role might be attributed to the influence of cytokine polymorphisms on the efficiency of immune response against infectious diseases that have been the principal selection in oldest old. Here are reported data on the evaluation of the frequency of the functional polymorphisms at genes coding for TNF-alpha (-308G-->A) and IL-10 (-1082G-->A), analysed by ARMS-PCR, in a group of Sicilian patients affected by chronic lung tuberculosis (TBC) compared to that from a group of healthy individuals living in the same region. Data obtained demonstrated a reduction of -308GG TNF homozygous individuals in TBC affected subject group. In the same group a reduction of IL-10 -1082A/* carriers was found. Our results seem to suggest that multiple genetic traits may affect the capacity to cope with an infectious agents and this might predispose to an overt disease. Moreover these data are in agreement with previous reports suggesting that a balanced interaction among pro- and anti-inflammatory molecules it is a key point for conditioning the life span expectancy.  相似文献   
6.
Cancer is generally recognized as an age-related disease. In fact, incidence and mortality rates of most human cancers increase consistently with age up to 90 years, but they plateau and decline thereafter. A low-grade systemic inflammation characterizes ageing and this pro-inflammatory status underlies biological mechanisms responsible for age-related inflammatory diseases. On the other hand, clinical and epidemiological studies show a strong association between chronic infection, inflammation and cancer and indicate that even in tumours not directly linked to pathogens, the microenvironment is characterized by the presence of a smouldering inflammation, fuelled primarily by stromal leukocytes. In this review, we have briefly mentioned inflammatory mediators involved in cancer although we decided to choose the ones which show a strict association with ageing and longevity. Inflammation is necessary to manage with damaging agents and is crucial for survival. But, in our opinion, the pro-inflammatory status of ageing might be one of the mechanisms which relate cancer to ageing. The most appropriate inflammatory genes have been selected to survive and to reproduce. Paradoxically, inflammatory age-related diseases (including cancer) are the marks of the same evolutionistic trait. Centenarians are characterized by a higher frequency of genetic markers associated with better control of inflammation. The reduced capacity of centenarians to mount inflammatory responses appears to exert a protective effect towards the development of those age-related pathologies having a strong inflammatory pathogenetic component, including cancer. All in all, centenarians seem to carry a genetic background with a peculiar resistance to cancer which is also an anti-inflammatory profile.  相似文献   
7.
The pro-inflammatory cytokine interleukin(IL)-1beta is a main component in inflammatory pathways and is overexpressed in the brain of Alzheimer's disease (AD) patients. Several studies report associations between IL-1beta polymorphisms and AD, but findings from different studies are controversial. Our aim was to verify the correlation between the single nucleotide polymorphisms (SNPs) of the IL-1beta, at sites -511 and +3953, and AD by meta-analysis. Computerized bibliographic searches of PUBMED and AlzGene database (http://www.alzgene.org) were supplemented with manual searches of reference lists. There is evidence for association between IL-1beta +3953 SNP and AD, with an OR=1.60 (95% C.I.: 1.16-2.22; Z=2.83 p=0.005) for TT genotype. No significant difference in genotype distribution of the IL-1beta -511 SNP in AD was obtained, but high between-study heterogeneity was found. To reduce heterogeneity, subgroup analyses were performed using, as stratifying variables, characteristics of the population under study (age, gender, type of AD diagnosis, Mini Mental State Examination of the controls) and characteristics related to the study design (statistical power of individual studies). The frequency of the IL-1beta -511 TT genotype resulted significantly higher than other genotypes only when the Caucasian studies with the highest statistical power were included in the subgroup analysis (OR=1.32; 95% C.I.: 1.03-1.69; p=0.03), with no evidence of between-study heterogeneity. Our data support an association between the TT genotype of IL-1beta +3953 SNP and AD, and suggest a possible association of the -511 TT genotype. Unreplicability of the results seems to be due mainly to the lack of statistical power of the individual studies.  相似文献   
8.
In the elderly, the most common cause of dementia is Alzheimer disease (AD), which is responsible for the age-related progressive neurodegenerative inflammatory condition mediated by the disease. It has been seen that several genetic and environmental factors are involved in AD onset. Epidemiologic data suggest that some genetic determinants of AD might reside in those polymorphisms that regulate immune inflammatory responses, such as the major histocompatibility complex (MHC). Therefore, several MHC polymorphisms have been in the spotlight of a large number of AD association studies. A possible association of HLA-A2 allele with increased susceptibility to AD has been the subject of debate for more than 20 years, even if the results of these studies, in the various populations, are discordant. Thus, to gain insight in this matter, the authors have studied the HLA-A2 allele for a possible association with sporadic AD in a homogeneous population of Italian patients. For this reason, the distribution of HLA-A2 allele in patients with sporadic AD and controls was analyzed by PCR-SSP assay. The results demonstrated a significant difference in the frequency of HLA-A2 allele between patients with sporadic AD and controls (46% versus 38%). Thus, these data confirm a positive role of HLA-A2 allele in the risk of developing AD. However, some of the observed discrepancies may result from clinical or genetic heterogeneity of the populations under study or methodologic biases. Besides, whenever external agents such as viruses play a role, these might different in the various populations leading to various associations. However, it has to be taken into account that there are many molecular HLA-A2 subtypes with different frequencies in various populations. Therefore, further studies should include molecular typing of HLA-A2 subtypes.  相似文献   
9.
Alzheimer disease (AD) is the most common form of dementia with complex etiology and multifactorial origin. Although several neurochemical deficits have been described in AD patients, explanation of the nature of the cognitive disturbance is focused on the "cholinergic hypothesis." The neuronal nicotinic acetylcholine receptor (neuronal nAChR) belongs to the superfamily of ionic channel activated by ligand. This paper presents a population-based population association study, testing the hypothesis that variants of the nAChR gene confer genetic susceptibility to AD. The authors analyzed two cohorts constituted by 60 controls and 80 AD patients in which significant increase of 594T polymorphism in patients affected by AD versus controls was found. However, further studies are necessary to confirm this polymorphism trend and to establish the polymorphism functionality and its correlation with behavioral and cognitive deficit.  相似文献   
10.
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