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11.
HLA-DRB1*1602 allele is positively associated with HPV cervical infection in Bolivian Andean women 总被引:3,自引:0,他引:3
Cervantes J Lema C Valentina Hurtado L Andrade R Hurtado Gomez L Torrico L Zegarra L Quiroga G Asturizaga D Dulon A Prada R Panoso W Yashiki S Fujiyoshi T Sonoda S 《Human immunology》2003,64(9):890-895
Incidence of cervical cancer is high among Bolivian Andean women. Human papillomavirus (HPV) infection is known as the major risk factor of cervical cancer. The host immune system plays an important role in the outcome of HPV infection and associated malignancies. In order to study the immunogenetic background of Bolivian Andean women with regard to HPV infection status, we compared HLA class I and class II allele frequencies between 37 HPV positive and 68 HPV negative Bolivian women. Demographic variables, including distribution of Andean ethnicities, were similar in both groups. Comparison of HLA class I allele frequencies between both groups indicated no significant difference. In contrast, HLA class II DRB1*1602 allele, an Amerindian allele, was significantly higher in the HPV positive women compared with HPV negative controls (chi(2) = 5.2, p < 0.05, odds ratio = 3.17; 95% confidence interval = 1.4-8.8). HPV types present in the HPV positive group were HPV-18, -16, -31, -33, and -58. These results suggest that HLA class II DRB1*1602 may confer susceptibility to infection with genetically related HPV types. This is the first report of an HLA class II association with HPV infection in an Andean population. 相似文献
12.
Multiple genetic typing of Salmonella enterica serotype typhimurium isolates of different phage types (DT104, U302, DT204b,and DT49) from animals and humans in England,Wales, and Northern Ireland
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Liebana E Garcia-Migura L Clouting C Clifton-Hadley FA Lindsay E Threlfall EJ McDowell SW Davies RH 《Journal of clinical microbiology》2002,40(12):4450-4456
Salmonella enterica serotype Typhimurium is a common cause of salmonellosis among humans and animals in England, Wales, and Northern Ireland. Phage types DT104 and U302 were the most prevalent types in both livestock and humans in 2001. In addition, Salmonella serotype Typhimurium DT204b was responsible for a recent international outbreak involving England. A total of 119 isolates from humans (n = 28) and animals or their environment (n = 91), belonging to DT104 (n = 66), U302 (n = 33), DT204b (n = 12), and DT49 (n = 8), were fingerprinted by a combination of well-established genetic methods (pulsed-field gel electrophoresis [PFGE], PstI/SphI [PS] ribotyping, and plasmid profiling). The different techniques identified different degrees of polymorphism (from greatest to least, plasmid profiling [40 types], PS ribotyping [34 types], and PFGE [23 types]). It seems clear that a prevalent genomic clone, as well as a variety of less frequent clones, is present for each of the phage types. In most cases, the prevalent clones appeared within isolates from several animal species and from several geographical locations. We did not find clear evidence of a higher degree of diversity for any of the animal species included, or of any link between isolates from particular animal species and humans. The data presented show the inaccuracy of drawing epidemiological conclusions based on a single fingerprinting method. Strains that share one of the markers do not necessarily belong to the same clone, and a multiple typing approach is required to enable enough discrimination to track strains for epidemiological investigations. 相似文献
13.
Ibáñez L Potau N Enriquez G Marcos MV de Zegher F 《Human reproduction (Oxford, England)》2003,18(8):1565-1569
BACKGROUND: Fetal growth restraint has been associated with FSH hypersecretion in early infancy and in early post-menarche, and with reduced uterine and ovarian size in adolescence. It is unknown whether these reproductive anomalies persist, respectively, into late infancy and into the reproductive age range. METHODS: We report follow-up findings in two age groups of girls. A cohort of infants [n=26; n=10 born appropriate-for-gestational-age (AGA) and n=16 born small-for-gestational-age (SGA)], who had been studied at the age of approximately 4 months, was assessed again at the age of 12 months. A cohort of teenagers (n=28), who had been studied at the age of approximately 14 years, was assessed again at the age of approximately 18 years; this group was complemented by a transversal cohort of similar age (n=19) for a total of 47 young women (n=27 AGA; n=20 SGA). In infants, only serum FSH was measured; adolescents underwent endocrine-metabolic screening, ultrasound assessment of uterine-ovarian size, and evaluation of body composition by dual X-ray absorptiometry. RESULTS: Serum FSH levels were higher in SGA than AGA infant girls at 4 and 12 months, and higher in SGA than AGA adolescents at 14 and 18 years (all P<0.01). Longitudinal ultrasound assessments disclosed a late-adolescent increment of uterine size that was less obvious in SGA than AGA girls. In contrast, ovarian volume remained stable in both subgroups. Compilation of longitudinal and transversal results at 18 years of age corroborated the persistent reduction in the uterine size of SGA girls (by approximately 20%; P<0.005) and in their ovarian volume (by approximately 40%; P<0.0001); moreover, SGA girls displayed not only a persistent elevation of FSH (by approximately 50%; P<0.001), but also a rise of LH and fasting insulin, as well as an excess of abdominal fat (all P<0.01). CONCLUSIONS: The gynaecology of young women born SGA was found to be characterized by hypergonadotrophinaemia and by a reduced uterine and ovarian size. 相似文献
14.
Anete M. Francisco‐Bagnariolli Spencer L.M. Payão Rosa S. Kawasaki‐Oyama Daher Sabbag Filho Rosimeire Segato Roger W. de Labio Maria de Lourdes L.F. Chauffaille Jean H. Priest 《American journal of medical genetics. Part A》2001,103(4):302-307
We report on a familial t(4;7)(q28;p22) with 2:2 adjacent‐1 unbalanced segregation producing duplication of 4q28→qter in multiple offspring. Within the large four‐generation pedigree, a carrier had a reproductive outcome that was approximately equal for 1) the balanced translocation, 2) normal chromosomes, and 3) viable 4q trisomy or pregnancy loss. The three individuals with chromosomal confirmation of trisomy 4q28→qter (comprising approximately 1.8% of the haploid autosomal length) had similar mental and developmental retardation, hypotonia, restricted speech, seizures, and facial anomalies but no cardiac, renal, or skeletal anomalies. It is suggested that these latter severe malformations, associated with the classic 4q2 to 3 group of anomalies, were from an imbalance outside 4q28→qter and were not necessarily related to the relatively large size of the trisomic segment. Multiple different chromosomes are reported to be rearranged with 4q in the production of distal 4q trisomy. The incidence of 4q rearrangement remains unexplained, but once it is present in a family, viability of a large trisomy in 4q seems to explain the number of affected individuals reported. © 2001 Wiley‐Liss, Inc. 相似文献
15.
Rotavirus diarrhea severity is related to the VP4 type in Mexican children 总被引:6,自引:0,他引:6
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Mota-Hernández F Calva JJ Gutiérrez-Camacho C Villa-Contreras S Arias CF Padilla-Noriega L Guiscafré-Gallardo H de Lourdes Guerrero M López S Muñoz O Contreras JF Cedillo R Herrera I Puerto FI 《Journal of clinical microbiology》2003,41(7):3158-3162
This report is of a community-based case control study to assess whether the severity of acute diarrhea by rotavirus (RV) in young children is associated with a particular VP7 (G) or VP4 (P) RV serotype. Five hundred twenty children younger than 2 years of age with diarrhea lasting less than 3 days were age and gender matched with 520 children with no diarrhea. The G and P serotypes were determined with specific monoclonal antibodies, and the VP4 serotype specificity in a subgroup was confirmed by genotyping. Infection with a G3 serotype led to a higher risk of diarrhea than infection with a G1 serotype. Infection with a G3-nontypeable-P serotype was associated with more severe gastroenteritis than infection with a G3 (or G1) P1A[8] serotype. A child with diarrhea-associated dehydration was almost five times more likely to be infected with a G3-nontypeable-P serotype than a child without dehydration (P < 0.001). Moreover, the two predominant monotypes within serotype P1A[8] had significantly different clinical manifestations. In this study, the severity of RV-associated diarrhea was related to different P serotypes rather than to G serotypes. The relationship between serotype and clinical outcomes seems to be complex and to vary among different geographic areas. 相似文献
16.
BACKGROUND: Low-dose flutamide-metformin has been developed as a background therapy for non-obese adolescents and young women with hyperinsulinaemic hyperandrogenism, a variant of polycystic ovary syndrome (PCOS). We verified whether the lipolytic efficacy of flutamide-metformin in women with PCOS is enhanced by giving an oral contraceptive (OC) co-therapy that contains drospirenone, instead of gestodene, as progestin. METHODS: An open-labelled study was carried out in which non-obese women with PCOS (n = 29; age approximately 20 years), who had been on a combination of flutamide (62.5 mg/day), metformin (850 mg/day) and ethinylestradiol-gestodene for 8-15 months, were randomized for replacement of the gestodene OC by a drospirenone OC. Assessments of endocrine-metabolic state and body composition (by dual-energy X-ray absorptiometry) were performed at randomization and after 6 months. RESULTS: The switch to drospirenone OC was accompanied by a reduction of total and abdominal fat (mean -0.8 and -0.5 kg) and by an increment of lean body mass (+0.6 kg; all P < 0.01), so that body adiposity was strikingly reduced without changing body weight. CONCLUSION: In non-obese women with PCOS, low-dose flutamide-metformin reduces total and abdominal fat excess more effectively if contraceptive co-therapy contains drospirenone, instead of gestodene, as progestin. 相似文献
17.
Teresa Cabrera Maria Angustias Fernandez Angels Sierra Antonio Garrido Alfonso Herruzo Agustin Escobedo Angels Fabra Federico Garrido 《Human immunology》1996,50(2):127-134
We studied 105 tumor samples obtained from patients diagnosed as having breast carcinomas for HLA class I and II (DR) antigen expression, using a panel of mAbs defining HLA-monomorphic, locus-specific and allele-specific determinants. Peripheral blood lymphocytes from patients were also typed for HLA alleles. The results indicated total HLA class I losses in 55 patients (52.3%), HLA-A locus losses in four patients (3.8%), HLA-B locus losses in eight patients (7.6%), and A, B, locus losses in 10 patients (9.5%). The remaining 28 patients whose tissues reacted positively with monomorphic- and locus-specific mAbs were tested for HLA allelic losses using several anti-HLA mAbs defining A2, A3, A9, B8, B12, etc. Of these 28 patients, 16 (57%) showed one or more losses of HLA reactivity. These results indicated that in 88.5% of patients we detected a particular HLA-altered tumor phenotype. The downregulation of HLA class I antigens in breast carcinomas may thus be more frequent than previously reported, and patients without HLA class I downregulation may be the exception rather than the rule. It cannot be ruled out that HLA alterations are present in some of the 12 patients with an apparently normal HLA phenotype, as some HLA alleles could not be studied because of the lack of appropriate mAbs. These HLA alterations could represent an important step associated with tumor invasion, conferring to the tumor cells the ability to escape from T-lymphocyte recognition. 相似文献
18.
Tania C. Araújo-Jorge Maria de Nazareth Leal de Meirelles Lourdes Isaac 《Parasitology research》1990,76(7):545-552
We report that alpha-2-macroglobulin (A2M), the physiologically important plasma protease inhibitor and suspected immunomodulator, alters the functional ability of murine resident peritoneal macrophages (RM) to ingest and kill the infective trypomastigote stage ofTrypanosoma cruzi, the aetiological agent of Chagas' disease. Treatment of RM with 500 g/ml A2M for 30 min enhanced the uptake of trypomastigotes, epimastigotes, and amastigotes by 125%, 46%, and 300%, respectively. The same treatment also increased the phagocytosis of sheep erythrocytes opsonized with complement and IgG as well as of galactosylated asialoerythrocytes. After 60–90 min parasite-cell interaction, epi-and amastigotes were killed by the RM, whereas the infection with trypomastigotes was controlled only after 24 h. Other protease inhibitors, bovine serum albumin, and LPS showed no such effect. The production of hydrogen peroxide was not affected by A2M treatment, but the ultrastructural aspects showed trypomastigote damage and enhancement of macrophage membrane ruffling, indicative of macrophage activation. These results suggest that A2M has the ability to modulate, at least functionally, certain receptor-mediated endocytic pathways that, in concert with an activation of possibly oxygen-independent microbicidal mechanisms, could contribute to resistance against the parasite.Abbreviations A2M
alpha-2-macroglobulin
- F-A2M
fast A2M
- S-A2M
slow A2M
- RM
resident macrophages
- BT
bloodstream trypomastigotes
- EPI
epimastigotes
- AMA
amastigotes
- DMEM
Dulbecco's Modified Eagle Medium
- PBS
phosphate-buffered saline
- BSA
bovine serum albumin
- LPS
bacto lipopolysaccharide
- STI
sovoean trypsin inhibitor
- PPA
pepstatin A
- LPT
leupeptin
- PNT
1, 10-phenanthroline
- TLCK
N--tosy-L-lysine-chloromethylketone
- E
sheep erythrocyte
- aE
asialoerythrocyte
- Gal R
receptors for galactosylated particles 相似文献
19.
Genetic diversity among clinical isolates of Candida glabrata analyzed by randomly amplified polymorphic DNA and multilocus enzyme electrophoresis analyses
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Boldo XM Villa-Tanaca L Zúñiga G Hernández-Rodríguez C 《Journal of clinical microbiology》2003,41(10):4799-4804
The genetic diversity of 47 clinical and reference strains of Candida glabrata from several geographical origins and diverse clinical disorders, with different antifungal susceptibilities, as well as their genetic relationships were studied through multilocus enzyme electrophoresis (MLEE) and randomly amplified polymorphic DNA (RAPD) techniques. The genetic diversity estimated for 11 MLEE loci measured as average heterozygosity (h) was 0.055. A high level of genetic relatedness among isolates was established by cluster analysis. Forty-nine RAPD markers were analyzed, and the average genetic diversity among isolates, estimated by Shannon's index (Ho), was 0.372. The PhiST values estimated through an analysis of molecular variance to assess genetic differentiation among isolates revealed no genetic differentiation among them. Our results revealed very low genetic diversity among isolates, a lack of differentiation, and no association with their geographic origin and the clinical characteristics. 相似文献
20.
BACKGROUND: Rates of remission and relapse were studied over more than 2 years in a sample of Spanish outpatients with DSM-III-R criteria of unipolar major depressive episodes. METHODS: Patients were treated following standardised pharmacological protocols at our centre. In the first visit, the structured clinical interview for DSM-III-R (SCID) was used. The following visits were held monthly. Phases of evolution were recorded using the Hamilton Depression Rating Scale (HDRS), applying the Frank criteria. RESULTS: A significantly greater proportion of relapse was observed in the partial remission group compared to the complete remission one. The rate of relapses for patients in complete remission was 15.18%, while for patients in partial remission was 67.61%. Partial remission was significantly associated with relapses. LIMITATIONS: The short duration of the study and the decreasing sample size during the follow-up. CONCLUSIONS: Partial remission after a depressive episode seems to be strongly associated with relapses. Moreover, this clinical factor could by itself fully predict short-term relapses. CLINICAL RELEVANCE: The study shows the importance of reaching complete remission to decrease the rate of short-term relapses. 相似文献