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71.
The aim of this study was to evaluate the prevalence of virulence genotypes, namely cagA, vacA and babA2, of Helicobacter pylori strains isolated from Portuguese adults and children presenting gastroduodenal pathology. One hundred thirty-six strains were studied, 82 isolated from adult patients (50 with nonulcerative gastritis and 32 with active peptic ulcer) and 58 isolated from children (54 with nonulcerative gastritis and 4 with duodenal ulcer). Genotyping of cagA, vacA and babA2 was assessed by polymerase chain reaction. Overall, Helicobacter pylori strains carrying more virulent genotypes were much more prevalent in adults than in children, particularly the type I (vacAs1- and cagA-positive) and the triple-positive (vacAs1-, cagA- and babA2-positive) strains (P<0.001). A subpopulation of adults and children with nonulcerative gastritis was also studied, and differences in the prevalence of virulent genotypes were observed, either for individual genotypes (P=0.017 for cagA, P=0.010 for vacAs1) or in combinations, i.e. the type I genotype (P=0.005) and the triple-positive strains (P=0.031). There was no difference between the two populations in the distribution of babA2 and m1/m2 genotypes. Considering the cohort effect in the epidemiology of Helicobacter pylori infection, these results suggest that different strains might circulate during different periods of time, or that, after infection in childhood, individual strains will undergo changes during the course of infection. Electronic Publication  相似文献   
72.
目的:利用体外培养人脐静脉内皮细胞,观察中药红景天对细胞生长的影响,初步探讨急、慢性高原病患者服用中药红景天防治高原病及改善症状等的作用机制。方法:培养人脐静脉内皮细胞EVC-304,设对照组与加药组,加药组分别加入不同浓度的红景天,培养3d后计数。加药组及对照组细胞用瑞氏染料染色并拍照。收集细胞以流式细胞术检测细胞周期。结果:对照组细胞形态正常,成梭形,排列紧密,分散均匀。加药组细胞数量明显减少,细胞皱缩,聚集成团,形态各异。流式细胞术检测显示加药组G1期细胞含量增多,S期细胞减少。结论:红景天具有抑制血管内皮细胞生长的作用,可能是通过抑制细胞的增殖来抑制内皮细胞生长。抑制血管内皮细胞生长对于阻止血管内膜增生,防止形成肺动脉高压,降低慢性高原病发病率具有实际应用意义。  相似文献   
73.
A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doen?as Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers.  相似文献   
74.
The cattle tick, Rhipicephalus (Boophilus) microplus, has caused serious harm to livestock raising in Brazil, considering the costs of controlling it, loss of revenue due to smaller production of milk and meat, and damage to leather, in addition to transmitting diseases. The use of medicinal plants is considered an alternative to the recurring resistance to chemicals. Due to the need for efficient alternatives with less environmental impact, this study aimed to develop contact formulations with essential oils from the Java citronella (Cymbopogon winterianus) and clove (Syzygium aromaticum) plants and to assess in vitro the effects in different stages of the tick cycle. In the present study, concentrations from 0.5–15.0 % of the essential oils incorporated in the formulations were used. The ticks from different geographical areas were treated with those formulations, and their effects on the production levels of eggs, on the larvae hatching, and their efficiency on ticks were assessed. The obtained results were compared with other commercial acaricidal products. After the 20th day of treatment, the formulations with citronella essential oil had 2.09–55.51 % efficiency, depending on the concentration of the oil incorporated. The efficiency of the treatment with formulations containing clove essential oil was higher, from 92.47–100 %. The results showed the acaricidal effects of the formulations tested when compared to commercial chemical products. In vivo studies should be performed in order to assess the efficiency of those formulations in the fields, aiming to use these products as an alternative for controlling cattle ticks.  相似文献   
75.
Objective: To present a case of an early treatment of cardiac intraperitoneal teratoma (IPT) in a newborn and its associated systematic literature review.

Methods: We presented a case of a newborn with IPT but without hydrops and having a good perinatal outcome after cardiac surgery. Using the PubMed database, we conducted a systematic literature review of articles regarding cases with cardiac IPT diagnosed and treated in the neonatal period and published in English from 2004 onward. We excluded cases that involved fetal death or interrupted gestation events.

Results: In total, 38 cases of IPT from 31 articles were included. The mean?±?standard deviation of the gestational age at diagnosis and delivery were 27.9?±?5.7 and 33.0?±?3.5 weeks, respectively, and that of birth weight was 2373?±?834.5?g. The majority of fetuses (42.1%) were males. Pericardial effusion was the most common symptom (60.5%) followed by hydrops (42.1%) and respiratory distress (42.1%). Intrauterine procedure was not performed in 63.1% of cases, and 71.0% of newborns were alive.

Conclusions: IPT in newborns is usually associated with a good prognosis without the need for intrauterine procedures. Cases with IPT-related death are associated with hemodynamic impairment in fetuses with hydrops.  相似文献   
76.
Objective: Studies focusing on telomere attrition in newborns and what factors could be involved in this issue are sparse; most reports have been in adult populations. Thereby, the aim of this study was to present an overview of what is currently known about the relationship between environmental exposure of the fetus during pregnancy and telomere length outcomes in early life.

Methods: The MEDLINE (via PubMed) and Bireme databases were searched for studies published until 1 June 2016. Studies that reported telomere length measurement from birth to age 1 year were included.

Results: Fifteen articles were selected that evaluated possible relationships between maternal smoking, hyperglycemia, hypertension, sleep apnea, psychological stress, folate concentration in early pregnancy, and radiation, in addition to small-for-gestational-age status and preterm birth. We found that sleep apnea, psychological stress, and folate concentration in early pregnancy were associated with telomere shortening in the newborn. No association was found with radiation, small-for-gestational-age status, or preterm birth. Results for maternal smoking, hyperglycemia, and hypertension were conflicting, and further studies should be considered.

Conclusion: The actual clinical implications of these findings have yet to be investigated.  相似文献   

77.
This study focuses on Brazilian mothers who gave birth to premature babies who were discharged from hospital using the Kangaroo Mother Care Method. While mothers left the hospital breastfeeding exclusively, once back at home, they abandoned exclusive breastfeeding because of insufficient breast milk (IBM). In this project we explored how IBM was interpreted by mothers within their social context. Participatory research using the Creative Sensitive Method was done in the homes of mothers with family members and neighbours. We described the conflicting social discourse that influenced the mothers' perception of IBM and explored their sources of distress. At the hospital and Kangaroo ward, mothers considered that clinicians recognized they were experiencing IBM and thus supported them to overcome this problem. Back at home and in their community, other sources of stress generated anxiety such as: the lack of outpatient clinical support, and conflicting local norms to care and feed premature babies. These difficulties combined with economic constraints and discontinuity in models of health care led mothers to lose confidence in their breastfeeding capacity. Mothers, thus, rapidly replaced exclusive breastfeeding by mixed feeding or formula feeding. Our analysis suggests that IBM in our sample was the result of a socio-somatic process. Recommendations are proposed to help overcome IBM and corresponding contextual barriers to exclusive breastfeeding.  相似文献   
78.
79.
Decapitation and ecdysone therapy on the population dynamics of the Trypanosoma cruzi Dm28c clone in the stomach, small intestine and rectum of fifth-instar larvae of Rhodnius prolixus were investigated. Parasites were not found in the small intestine and rectum of decapitated insects after 10 days post-infection (p.i.). Decapitated ecdysone-supplemented insects sustained the flagellate infection in both gut compartments. In the rectum, the population density of parasites increased 5-fold in ecdysone-treated decapitated larvae and 7-fold in control insects. Epimastigote forms dominated with 40-65%, intermediate stages and round forms varied over 10-35% in the stomach, small intestine and rectum in both insect groups. Low numbers of metacyclic trypomastigotes were observed in the stomach and small intestine of the control group and decapitated insects supplemented with ecdysone but, at 15 days p.i., this form of flagellate reached about 20% in the rectum of the control insects. In the entire gut, at 30 days p.i., 23% of parasites in the control group and 8% in the decapitated insects treated with ecdysone were found. These results indicate that a head factor, possibly the prothoracicotropic hormone from the brain which stimulates ecdysone production by the prothoracic glands, may act directly or indirectly to stimulate the development of epimastigotes and round forms of the parasite and that a single ecdysone treatment is not able to fully reverse metacyclogenesis in decapitated R. prolixus.  相似文献   
80.
In 1990 our group reported a patient with autoimmune hemolytic anemia and high titers of IgM anticardiolipin antibodies that cross-reacted with phosphatidylcholine (PTC). These autoantibodies also recognized bromelain-treated erythrocytes (BrE) and in vitro aged erythrocytes. The epitope exposed with this treatment is PTC. To detect and characterize antiphosphatidylcholine antibodies (anti-PTC) in a normal human population, we studied by ELISA the presence of serum anti-PTC (IgG and IgM) in clinically healthy human subjects. The most representative samples were also studied for IgG or IgM activity against BrE by flow cytometry, rheumatoid factor activity, anti-dsDNA, anti-ssDNA by ELISA and by indirect immunofluorecence (IIF) using HEp-2 line and a healthy human fibroblast strain as substratum. Eighty five percent of sera had IgM anti-PTC and none had IgG. IgM antibodies against BrE were inhibited by PTC micelles (mPTC). Anti-PTC were also inhibited by phosphorylcholine and phosphatidic acid. Aggregated gammaglobulin (AGG) reactivity was inhibited by dsDNA and mPTC. The IgM anti-dsDNA activity was inhibited by soluble dsDNA, AGG and mPTC. All sera gave intermediate filaments pattern by IIF and reacted against purified vimentin by dot blot and Western blot.Our study shows hemolytic IgM anti-PTC present in normal human serum. The main epitope recognized by these autoantibodies is phosphorylcholine. The physicochemical characteristics, crossreactivity with self-antigens and functional properties are typical features of natural autoantibodies.  相似文献   
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