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991.
Marino MC de Oliveira CA Rocha AM Rocha GA Clementino NC Antunes LF Oliveira RA Martins AS Del Puerto HL D'Almeida V Galdieri L Pedroso ER Cabral MM Nogueira AM Queiroz DM 《Gut》2007,56(4):469-474
BACKGROUND: Helicobacter pylori gastritis may lead to impairment of the production of pepsinogen and acid, which are essential to cobalamin absorption. In turn, cobalamin deficiency leads to hyperhomocysteinaemia, a risk factor for cardio and cerebrovascular diseases. AIM: To evaluate the effect of H pylori eradication on plasma homocysteine levels in elderly patients. PATIENTS: Sixty-two H pylori-positive elderly patients with cobalamin deficiency were prospectively studied. METHODS: Homocysteine and cobalamin concentrations were determined before, 6 and 12 months after H pylori eradication. RESULTS: Corpus atrophy was observed in a few patients; otherwise, in most of them, the degree of corpus gastritis was moderate to severe. The initial homocysteine mean (SD) levels decreased from 41.0 (27.1) to 21.6 (10.1) micromol/l at the 6 month follow-up (p<0.001) and to 13.1 (3.8) micromol/l 12 months after H pylori eradication (p<0.001). Conversely, initial cobalamin mean levels increased from 145.5 (48.7) pmol/l to 209.8 (87.1) pmol/l and to 271.2 (140.8) pmol/l, 6 and 12 months after treatment, respectively (p<0.001 for both). Although the erythrocyte mean corpuscular volume was within reference intervals, it decreased significantly 6 (p = 0.002) and 12 (p<0.001) months after treatment. CONCLUSIONS: The results of the current study demonstrated that the eradication of H pylori in elderly patients with cobalamin deficiency is followed by increasing of cobalamin and decreasing of homocysteine blood levels. 相似文献
992.
McMahon SK Ferreira LD Ratnam N Davey RJ Youngs LM Davis EA Fournier PA Jones TW 《The Journal of clinical endocrinology and metabolism》2007,92(3):963-968
CONTEXT: Exercise increases the risk of hypoglycemia in type 1 diabetes. OBJECTIVE: This study aimed to investigate how the amount of glucose required to prevent an exercise-mediated fall in glucose level changes over time in adolescents with type 1 diabetes. SETTING: The study took place at a tertiary pediatric referral center. DESIGN, PARTICIPANTS, AND INTERVENTION: Nine adolescents with type 1 diabetes mellitus (five males, four females, aged 16 +/- 1.8 yr, diabetes duration 8.2 +/- 4.1 yr, hemoglobin A1c 7.8 +/- 0.8%, mean +/- SD) were subjected on two different occasions to a rest or 45 min of exercise at 95% of their lactate threshold. Insulin was administered iv at a rate based on their usual insulin dose, with similar plasma insulin levels for both studies (82.1 +/- 19.0, exercise vs. 82.7 +/- 16.4 pmol/liter, rest). Glucose was infused to maintain euglycemia for 18 h. MAIN OUTCOME MEASURES: Glucose infusion rates required to maintain euglcycemia and levels of counterregulatory hormones were compared between rest and exercise study nights. RESULTS: Glucose infusion rates to maintain stable glucose levels were elevated during and shortly after exercise, compared with the rest study, and again from 7-11 h after exercise. Counterregulatory hormone levels were similar between exercise and rest studies except for peaks in the immediate postexercise period (epinephrine, norepinephrine, GH, and cortisol peaks: 375.6 +/- 146.9 pmol/liter, 5.59 +/- 0.73 nmol/liter, 71.9 +/- 14.8 mIU/liter, and 558 +/- 69 nmol/liter, respectively). CONCLUSIONS: The biphasic increase in glucose requirements to maintain euglycemia after exercise suggests a unique pattern of early and delayed risk for nocturnal hypoglycemia after afternoon exercise. 相似文献
993.
Ferreira I Boreham CA Twisk JW Gallagher AM Young IS Murray LJ Stehouwer CD 《Journal of hypertension》2007,25(5):1009-1020
OBJECTIVES: This study aimed to investigate whether the clustering of the risk factors of the metabolic syndrome (MetS) is associated with stiffness of central and peripheral arterial segments; whether these associations are similar in men and women; and whether insulin resistance and low-grade inflammation mediate any such associations. BACKGROUND: Increased arterial stiffness may explain, at least in part, the increased cardiovascular and diabetes risk associated with the MetS. However, the mechanisms linking the MetS to an increased arterial stiffness are incompletely understood, and gender differences may exist. METHODS: Cross-sectional analyses of data on 313 young men and women (mean age 23 years) from the Northern Ireland Young Hearts Project. Subjects were categorized according to the number of traits of the MetS; in addition a continuous MetS score was calculated. Arterial stiffness was assessed by measuring pulse wave velocity (PWV) in three arterial segments using a non-invasive optical method. RESULTS: The prevalence of the MetS was similar for men (10.6%) and women (10.5%). After adjustment for potential confounders and other cardiovascular risk factors, PWV of the three arterial segments investigated increased with increasing traits of the MetS in women only. Women with the MetS, as compared to those without risk factors of the syndrome, had greater PWV of the aorto-iliac (+14.0%, P = 0.016), the aorto-radial (+13.2%, P = 0.010) and aorto-dorsalis pedis (+11.8%, P = 0.011) segments. A great deal (up to 75%) of the association between the MetS and aortic-iliac PWV was mediated by heart rate, inflammation markers [C-reactive protein (CRP) and fibrinogen] and insulin resistance [homeostatic model assessment-insulin resistance (HOMA-IR)], whereas these variables did not explain much of the association between the MetS and PWV of the peripheral segments. CONCLUSIONS: Young women with the MetS show increased stiffness of peripheral and central arteries, a mechanism that may explain their increased cardiovascular risk. Low-grade inflammation, insulin resistance and sympathetic activation explain much of the adverse impact of the MetS on central, but not peripheral, arterial stiffness. 相似文献
994.
Moore DF Gelderman MP Ferreira PA Fuhrmann SR Yi H Elkahloun A Lix LM Brady RO Schiffmann R Goldin E 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(19):8065-8070
Fabry disease is a disorder of alpha-D-galactosyl-containing glycolipids resulting from a deficiency of alpha-galactosidase A. Patients have a poorly understood vascular dysregulation. We hypothesized that disease-related perturbation by using enzyme replacement therapy in the murine model of Fabry disease would provide insight into abnormal biological processes in Fabry disease. Gene expression analyses of the heart, aorta, and liver of male alpha-galactosidase A knockout mice 28 weeks of age were compared with that of WT mice. Microarray analyses were performed before and after six weekly injections of alpha-galactosidase A. Alteration of Rpgrip1 ranked highest statistically in all three organs when knockout mice were compared with WT, and its splice variants responded in a unique way to alpha-galactosidase A. Enzyme replacement therapy tended to not only normalize gene expression, e.g., reduce the overexpression of securin, but also specifically modified gene expression in each tissue examined. Following multiple comparison analysis, gene expression correlation graphs were constructed, and a priori hypotheses were examined by using structural equation modeling. This systems biology approach demonstrated multiple and complex parallel cellular abnormalities in Fabry disease. These abnormalities form the basis for informed, in a Bayesian sense, sequential, hypothesis-driven research that can be subsequently tested experimentally. 相似文献
995.
de Paiva TF Ribeiro HB Campanholo CB Gonçalves CR Terigoe DY de Souza BD 《Clinical rheumatology》2007,26(5):804-806
Behçet’s disease is a multisystemic vasculitis of unknown etiology, which is characterized by recurrent urogenital ulceration, cutaneous eruptions, ocular manifestations, arthritis and vasculitis, and its diagnosis is based on clinical criteria. Superior vena cava (SVC) thrombosis is a rare but well-recognized manifestation of Behçet’s disease, whereas SVC syndrome due to vasculopathy, without evidence of thrombosis, has not yet been described in the literature. The authors report the case of a patient with Behçet’s disease, who presented SVC syndrome with reduction in the lumen of the SVC due to thickening of the vessel wall, without evidence of thrombosis upon computed tomography and magnetic angioresonance. The patient received early anticoagulant therapy, corticosteroid and monthly cyclophosphamide pulse therapy. Clinical control without recurrence was observed after 6 months of follow-up. Behçet’s disease should be suspected in young patients presenting with SVC syndrome, in the absence of thrombosis or of a hypercoagulable state. 相似文献
996.
Brito A Almeida A Gonsalez CR Mendonça M Ferreira F Fernandes SS Duarte AJ Casseb J 《AIDS research and human retroviruses》2007,23(7):906-912
Chemokine receptors are used by HIV-1 for entry into CD4+ T cells. The beta-chemokines are capable of inhibiting HIV replication. This study measured beta-chemokine macrophage inflammatory protein (MIP)-1alpha and MIP-1beta levels and determined the CCR5 and CXCR4 expression on T cells in HIV-1-infected patients treated with HAART. The time of known HIV infection and time of HAART use were similar between failure and successful groups. The CD4+ T cell nadir was 163 vs. 251 cells/mm3, p = 0.07, for failure and successful groups, respectively. The successfully treated group, when compared with the failure group, had a higher median CD4+ T cells count (667 vs. 257 cells/mm3; p = 0.003) as well as higher spontaneous MIP-1alpha (median of 4390 vs. 802 pg/ml, p = 0.03) and MIP-1beta (median of 2416 vs. 1117 pg/ml, p = 0.001) levels. The untreated patients had a higher number and intensity of CCR5- and CXCR4-expressing T cells. Higher levels of chemokines were not related to nadir CD4+ T and current CD8+ T cell counts. Successfully treated patients were able to produce higher amounts of beta-chemokines and normalize the coreceptor overexpression on T cells. These findings may have clinical implications, such as a new strategy of using chemokines as adjuvants in anti-HIV therapy. 相似文献
997.
998.
999.
Marta Regina Santin Adriana Oliveira dos Santos Celso Vataru Nakamura Benedito Prado Dias Filho Izabel Cristina Piloto Ferreira Tania Ueda-Nakamura 《Parasitology research》2009,105(6):1489-1496
Leishmaniasis causes considerable mortality throughout the world, affecting more than 12 million people. Cymbopogon citratus (DC) Stapf, Family Poaceae, is a widely used herb in tropical countries and is also known as a source of ethnomedicines.
In this study, the inhibitory effect and the morphological and ultrastructural alterations on Leishmania amazonensis by the essential oil (EO) of C. citratus and its main constituent, citral, were evaluated. The results showed that the antiproliferative activity of EO on promastigotes
and axenic amastigotes, and intracellular amastigote forms of L. amazonensis was significantly better than citral, and indicated a dose-dependent effect. Neither compound showed a cytotoxic effect on
macrophage strain J774G8. The promastigote forms of L. amazonensis underwent remarkable morphological and ultrastructural alterations compared with untreated cultures. These alterations were
visible by light, scanning, and transmission electron microscopy of promastigotes treated with EO and citral at concentrations
corresponding to the IC50 (1.7 and 8.0 μg/ml) and IC90 (3.2 and 25 μg/ml), respectively, after 72 h of incubation. This study revealed that citral-rich essential oil from C. citratus has promising antileishmanial properties, and is a good candidate for further research to develop a new anti-protozoan drug. 相似文献
1000.