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41.
Estimation of the genetic contribution of presenilin-1 and -2 mutations in a population-based study of presenile Alzheimer disease 总被引:11,自引:4,他引:11
Cruts M; van Duijn CM; Backhovens H; Van den Broeck M; Wehnert A; Serneels S; Sherrington R; Hutton M; Hardy J; St George-Hyslop PH; Hofman A; Van Broeckhoven C 《Human molecular genetics》1998,7(1):43-51
Two closely related genes, the presenilins ( PS ), located at chromosomes
14q24.3 and 1q42.1, have been identified for autosomal dominant Alzheimer
disease (AD) with onset age below 65 years (presenile AD). We performed a
systematic mutation analysis of all coding and 5'-non-coding exons of PS -1
and PS -2 in a population-based epidemiological series of 101 unrelated
familial and sporadic presenile AD cases. The familial cases included 10
patients of autosomal dominant AD families sampled for linkage analysis
studies. In all patients mutations in the amyloid precursor protein gene (
APP ) had previously been excluded. Four different PS -1 missense mutations
were identified in six familial cases, two of which where autosomal
dominant cases. Three mutations resulted in onset ages above 55 years, with
one segregating in an autosomal dominant family with mean onset age 64
years (range 50-78 years). One PS -2 mutation was identified in a sporadic
case with onset age 62 years. Our mutation data provided estimates for PS
-1 and PS -2 mutation frequencies in presenile AD of 6 and 1% respectively.
When family history was accounted for mutation frequencies for PS -1 were
9% in familial cases and 18% in autosomal dominant cases. Further,
polymorphisms were detected in the promoter and the 5'-non-coding region of
PS -1 and in intronic and exonic sequences of PS -2 that will be useful in
genetic association studies.
相似文献
42.
Analysis of human papillomavirus prevalence and TP53 polymorphism in head and neck squamous cell carcinomas 总被引:1,自引:0,他引:1
Cortezzi SS Provazzi PJ Sobrinho JS Mann-Prado JC Reis PM de Freitas SE Filho JF Fukuyama EE Cordeiro JA Cury PM Maniglia JV Villa LL Tajara EH Rahal P 《Cancer Genetics and Cytogenetics》2004,150(1):44-49
Head and neck squamous cell carcinoma is a disease associated with tobacco and alcohol abuse. There is evidence that the oncogenic human papillomavirus (HPV) may also be a risk for upper aerodigestive tract cancers. High-risk HPVs encode two early proteins, E6 and E7, that can bind to p53 and pRb, respectively, and induce its degradation or inactivation. The TP53 gene has a single polymorphism at codon 72 of exon 4 that encodes either arginine (Arg) or proline (Pro). The purpose of this study was to evaluate the role of HPV infection and TP53 polymorphism in head and neck cancer. We analyzed 50 tumors, as well swabs of oral mucosa from 142 control individuals, with a polymerase chain reaction technique. The prevalence of HPV in controls was 10.6% and in cancer specimens 16%. The frequency distribution of genotypes in controls was 50% Arg/Arg, 43% Arg/Pro and 7% Pro/Pro; in tumors, it was 52% Arg/Arg, 32% Arg/Pro, and 16% Pro/Pro. Contrary to the results of some studies on cervical cancer, no association between any TP53 genotype or allele and the development of head and neck cancer was observed, regardless of HPV status, except for the Pro/Pro genotype, which is associated with the absence of HPV. The arginine allele appears to protect against head and neck cancers. Also, the data showed that HPV infection results in no increased risk of developing head and neck tumors. 相似文献
43.
Beggan E Whyte D FitzGerald R de Freitas J McNamara A Callinan S Kelleher K 《Irish medical journal》2005,98(9):278-280
Human brucellosis remains a serious public health issue in Ireland. Clinical notifications in the Mid-Western Area (HSE-MWA) underestimate the burden of illness and attendant morbidity in the region. The diagnosis of acute and chronic human brucellosis depends on the clinical evidence and the results from laboratory serological testing or culture on rare occasion. This study examined the clinical evidence behind locally defined serological "positives" in the HSE-MWA from 2002 to 2003. Ninety cases were detected in 2002 and 31 in 2003. While sampling bias is likely to be present, aspects of brucellosis in Ireland were confirmed. Middle-aged males were most commonly affected. The majority of cases were linked to farming or veterinary practice. Symptoms such as sweats, fever and weight loss were commonly associated with acute brucellosis infection while malaise was common in acute and chronic brucellosis. A clear definition of what is notifiable is needed. Surveillance systems must appreciate the importance of both clinical and laboratory evidence to classify confirmed or probable brucellosis as paired sera were not common. Public health authorities must follow-up the clinical aspects for accurate national statistics. General practitioners in the Mid-West appear to be vigilant regarding brucellosis in their patients. Regional zoonoses committees are useful in monitoring disease prevalence in human and animal populations without compromising confidentiality. 相似文献
44.
Freitas RM Nascimento VS Vasconcelos SM Sousa FC Viana GS Fonteles MM 《Neuroscience letters》2004,365(2):102-105
The mechanism underlying the vulnerability of the brain to status epilepticus (SE) induced by pilocarpine remains unknown. Oxidative stress has been implicated in a variety of acute and chronic neurologic conditions, including SE. The present study was aimed at was investigating the changes in catalase activity after pilocarpine-induced seizures and SE. The Control group was treated with 0.9% saline (NaCl, subcutaneously (s.c.)) and sacrificed 1h after the treatment. Another group was treated with pilocarpine (400 mg/kg, s.c., Pilocarpine group) and sacrificed 1h after treatment. The catalase activity in the cerebellum, hippocampus, frontal cortex and striatum of Wistar rats was determined. The results have shown that pilocarpine administration and resulting SE produced a significant increase in the catalase activity in the hippocampus (36%), striatum (31%) and frontal cortex (15%) of treated adult rats. Nevertheless, in the adult rat cerebellum after SE induced by pilocarpine no change was observed in the catalase activity. Our results demonstrated a direct evidence of an increase in the activity of the scavenging enzyme (catalase) in different cerebral structures during seizure activity that could be responsible for eliminating oxygen free radicals and might be one of the compensatory mechanisms to avoid the development of oxidative stress during the establishment of SE induced by pilocarpine. Our reports also indicate clear regional differences in the catalase activity caused by pilocarpine-induced seizures and SE and the hippocampus might be the principal area affected and cerebellum does not modify for this parameter studied during epileptic activity. 相似文献
45.
All citizens (N = 22066) aged 16 to 65 of a medium-sized Belgiantown were personally invited to CPR training sessions held intheir neighbourhood. 1152 responded by attending a trainingsession. Those who did not so respond were surveyed (randomsample N=600) for reasons of their not coming. The sample fittedwell with census data for gender, age and suburb location butnot for job, because retired persons and women at home wereover represented. 123 persons did not want to answer the questions. 116 personssaid they were already trained in CPR, 276 said they would accepton a future occasion and 82 said they would not. Three personsdid not answer this question. There was no discrimination for job, gender and suburb locationbetween those who did and did not accept a future training opportunity,nor was the existence of a heart patient among relatives. Theolder the person, the less inclined was that person to participatein CPR training (age effect x2 = 17.17, d.f. = 9, P<0.05).The 276 who accepted future training, chose their workplace(221) and/or their social meeting place (club etc.) as the placewhere this future training should be held. We suggest that CPR training is well accepted and that the trainingopportunities should be given at places of work and social gatherings. 相似文献
46.
Vanessa Averof Honorato de Almeida Rafaela Alkmin da Costa Cristiane de Freitas Paganoti Fernanda Cristina Mikami Ana Maria da Silva Sousa Stela Verzinhasse Peres Marco Antonio Borges Lopes Rossana Pulcineli Vieira Francisco 《Nutrients》2021,13(6)
The aim of this study was to evaluate the Diet Quality Index (DQI) and the Physical Activity (PA) levels associated with adequacy of gestational weight gain in pregnant women with gestational diabetes mellitus (GDM). A total of 172 pregnant women with a single fetus and a diagnosis of GDM participated. Food intake was self-reported on the food frequency questionnaire and DQI was quantified using the index validated and revised for Brazil (DQI-R). To assess PA, the Pregnancy Physical Activity Questionnaire was administered. Gestational weight gain was classified, following the criteria of the Institute of Medicine, into adequate (AWG), insufficient (IWG), or excessive (EWG) weight gain. A multinomial logistic regression analysis was performed, with level of significance <0.05. The participants were divided into 3 groups: AWG (33.1%), IWG (27.3%), and EWG (39.5%). The analysis indicated that if the pregnant women PA fell into tertile 1 or 2, then they had a greater chance of having IWG, whereas those with the lowest scores on the DQI-R, whose PA fell into tertile 2, and pregestational obesity women had the greatest chance of having EWG. This study has shown that low PA levels may contribute towards IWG. On the other hand, a low final DQI-R score, representing inadequate food habits, low PA levels, and pregestational obesity may increase the chance of EWG in patients with GDM. 相似文献
47.
JORENS PH. G.; VAN DEN HEUVEL P. A.; CUYKENS J.-J.; VAN CAUWELAERT P. A.; PARIZEL G. A.; MERTENS A. N. 《European heart journal》1990,11(5):476-478
This article describes a case of infective aortic valve endocarditisdue to Fusarium oxysporum occurring 4 years after coronary arterybypass grafting. It is the first reported case of endocarditiscaused by Fusarium. 相似文献
48.
ERIKSSON L. I.; LENNMARKEN C.; STAUN P.; VIBY-MOGENSEN +M.D. PH.D. J. 《British journal of anaesthesia》1990,65(4):487-493
In order to evaluate the use of the post-tetanic count (PTC)method during repetitive administration of vecuronium, we studied20 patients allocated randomly to one of two groups: 10 patientsreceived droperidol-fentanyl anaesthesia (control group); 10other patients were given droperidol-fentanyl anaesthesia modifiedsubsequently by addition of 0.5% isoflurane (isoflurane group).Before tracheal intubation, a bolus dose of vecuronium 0.08mg kg1 was given i. v. followed by repeated doses of0.03 mg kg1. The twitch response of adductor polliciswas recorded after supramaximal stimulation of the ulnar nerveat the wrist using a Myograph 2000 neuromuscular transmissionanalyser. In the control group, a close correlation was foundbetween PTC and time to first reaction to train-of-four (TOF)nerve stimulation. This relationship was unchanged when comparingthe bolus dose and each of eight consecutive maintenance doses.Further, the degree and the duration of intense block were unchangedafter each of the eight maintenance doses. In the isofluranegroup, the relationship between PTC and time to first reactionto TOF stimulation remained unchanged after addition of isoflurane.However, isoflurane caused a significant prolongation of theduration of intense block and a corresponding lower PTC in allpatients. We conclude that PTC is a reliable method to evaluateintense neuromuscular block caused by vecuronium, even afterrepetitive administration of the drug and in combination with0.5% isoflurane.
Presented in part at the annual meeting of the American Societyof Anesthesiologists, San Francisco, October 1988. 相似文献
49.
Background: The complications of the gastric pouch in gastric bypass surgery are well known. Since the first report of this
surgery 30 years ago, new technical aspects that make it safer and more effective have been implemented. Methods: As a modification
of gastric bypass, the authors have performed 305 vertical banded gastroplasty-gastric bypass procedures. Two groups of patients
underwent the procedure: Group I (n = 206) without a limb of jejunum interposed between the gastric pouch and the excluded
stomach, and Group II (n = 99) with a limb of jejunum interposed between the pouch and the stomach. The results regarding
excess weight loss and complications of the gastric pouch during the first year after surgery were compared. Results: Age,
sex, initial weight, body mass index, and percentage of ideal weight were similar in both groups. Excess weight loss was also
similar. The complications in Group I were 1 leak, 3 left subphrenic abscesses, 2 erosive gastritis with bleeding, 1 stenosis
of the gastrojejunostomy, 1 perforated ulcer, and 4 marginal ulcers with bleeding. Two patients in Group II developed bleeding
from the staple-line. Conclusions: These preliminary data suggest that complications of the gastric pouch can be reduced by
interposing a limb of jejunum between the pouch and the excluded stomach. This is an early experience; long-term results are
pending. 相似文献
50.
V C Abílio F M Freitas M S Dolnikoff A M Castrucci R Frussa-Filho 《Neuropsychopharmacology》1999,45(12):1622-1629
BACKGROUND: This study examines the effects of long-term continuous exposure to light on dopaminergic supersensitivity induced by repeated treatment with haloperidol in rats. METHODS: Spontaneous general activity in an open-field (SGA) and stereotyped behavior induced by apomorphine (SB-APO) or amphetamine (SB-AMP) were used as experimental parameters. Rats were allocated to four groups in each experiment: saline-treated animals kept under a 12-hour light/dark cycle (LD) or 24-hour light/light cycle (LL), and 2 mg/kg haloperidol-treated animals kept under the above cycles. Plasma corticosterone concentration was also measured by radioimmunoassay in saline-treated rats kept under a LD or LL cycle. RESULTS: All the behavioral parameters used showed the development of central dopaminergic supersensitivity in rats kept under both cycles. Continuous exposure to light enhanced SGA and SB-AMP in both saline- and haloperidol-treated rats, but did not modify SB-APO. Animals kept under the LL cycle presented an increased plasma corticosterone concentration. CONCLUSIONS: Our results suggest that continuous exposure to light leads to an increase in dopaminergic function in both normal and "supersensitive" rats. This effect seems to be mediated by a presynaptic mechanism possibly involving corticosterone actions. 相似文献