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81.
BACKGROUND: Schistosoma haematobium infection causes severe urinary disease and considerable mortality. The factors that determine disease progression from mild to severe stages are not fully understood. METHODS: Here we describe a cross-sectional epidemiological study of kidney and bladder diseases in 2 Dogon populations with different exposure to S. haematobium infection. RESULTS: Early and high exposure resulted in more-severe disease, especially among young subjects, without clear evidence of a more-rapid development of immunity. Nevertheless, 50%-60% of subjects of all age classes in both villages showed no evidence of disease. Kidney and bladder disease peaked biphasically among young subjects and adults >25 years old. The first peak corresponded with infections of maximum intensity, whereas the second peak occurred among adults with infections of very low intensity. Kidney disease was correlated with circulating anodic antigen concentration in serum, whereas bladder disease was correlated with egg count and eosinophil cationic protein concentration in urine. Kidney and bladder disease did not correlate. Severe kidney disease was more frequent in certain families. CONCLUSIONS: The frequency of urinary disease is increased by infections acquired early during life, is regulated by strong clinical immunity in certain subjects, and may be dependent on hereditary factors. Kidney and bladder disease may involve different mechanisms of pathogenesis, which may differ between children and adults.  相似文献   
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83.
Elevation of serum parathyroid hormone (PTH) level in eucalcemic patients after parathyroidectomy for primary hyperparathyroidism has been described in up to 40% of patients, but little is known about its etiology or clinical significance. To better understand the cause of this phenomenon, we studied 49 patients without renal dysfunction or osteomalacia who underwent parathyroidectomy for primary hyperparathyroidism. Patients were categorized into 2 groups based on their serum PTH and calcium levels after parathyroidectomy: (1) elevated PTH with eucalcemia (n = 21), (2) normal PTH with eucalcemia (n = 28). Elevation of serum PTH with eucalcemia after parathyroidectomy occurred in 43% of patients. Patients in group 1 had significantly higher preoperative and postoperative mean serum PTH levels and significantly lower postoperative serum levels of 1,25(OH)(2)D(3), 1,25(OH)(2)D(3)/25(OH)D(3) ratio, and 1,25(OH)(2)D(3)/PTH ratio compared with patients in group 2. Serum PTH in group 1 patients normalized as early as 3 months, but remained elevated in some patients for more than 4 years, and was not associated with development of recurrent hypercalcemia. Normalization of serum PTH in group 1 patients was associated with significant increase in 1,25(OH)(2)D(3) and 1,25(OH)(2)D(3)/PTH ratio. Our data suggest that elevation of serum PTH in eucalcemic patients after parathyroidectomy is a frequently reversible state of resistance of the kidneys to PTH-mediated 1-alpha hydroxylation of 25(OH)D(3) and does not signify subsequent recurrence of hyperparathyroidism.  相似文献   
84.
BACKGROUND: The rapid evolution of implantable cardioverter-defibrillator (ICD) leads has resulted in thinner active fixation leads. While these advances have made the leads more versatile, new configurations may be associated with unforeseen complications. OBJECTIVE: The purpose of this study was to determine the incidence of perforation and dislodgement of defibrillator leads in a single center in the year 2005. METHODS: All patients who underwent percutaneous ICD implantation at the Massachusetts General Hospital using an endocardial right ventricular lead were included in this study. The specific leads analyzed were the Riata (1580/1581 and 1590/1591, St. Jude Medical, St Paul, Minnesota, USA;) and Sprint Fidelis (6949-65, Medtronic, Minneapolis, Minnesota, USA.). Information was collected retrospectively. RESULTS: A total of 130 Riata leads and 111 Sprint Fidelis leads were implanted at the Massachusetts General Hospital during this time period. A total of five lead perforations occurred in patients implanted with the Riata lead as compared with none with the Sprint Fidelis lead (3.8% vs. 0%, respectively; P <.05). Two of the five patients with perforation required pericardiocentesis for tamponade. Clinical symptoms of perforation developed 1-10 days after implant. Moreover, there were five additional lead revisions in the Riata group, which were likely due to dislodgement and/or microperforation, as compared with none in the Sprint Fidelis group (7.7% vs. 0%, respectively; P <.005). CONCLUSIONS: In 2005, at one institution, there were significantly more cardiac perforations and lead revisions with the Riata lead as compared with the Sprint Fidelis right ventricular defibrillator lead. Further data are required to determine whether certain lead characteristics are responsible for this observation.  相似文献   
85.
The primary aim of this study was to assess potential barriers and motivators to blood and cord blood donation among African-American women. A telephone survey of African-American women, ages 18-30 years, in the St. Louis metropolitan area was performed. The survey was administered by trained telemarketing personnel using a Computer-Assisted Direct Interview (CADI) system. One hundred sixty-two women were surveyed. Common barriers to blood donation were inconvenience of donor sites (19%), fear of needles (16%), and too much time required to donate (15%). Potential motivators were increasing awareness of need for blood (43%), increasing the number of convenient donor locations (19%), and encouragement by spiritual leaders to have blood drives at their church (17%). Lack of awareness was the only identified barrier to cord blood donation. Most women surveyed (88%) indicated that they definitely or probably would donate cord blood. Strategies to increase the proportion of African-American blood and cord blood donations may include educating potential donors about the process and benefits of donation to particular patient populations and engaging church leadership in supporting blood and cord blood donations.  相似文献   
86.
BackgroundAlthough recommendations encourage daily moderate activities in post aortic dissection, very little data exists regarding cardiopulmonary exercise testing (CPET) to personalize those patient''s physical rehabilitation and assess their cardiovascular prognosis.DesignWe aimed at testing the prognostic insight of CPET regarding aortic and cardiovascular events by exploring a prospective cohort of patients followed‐up after acute aortic dissection.MethodsPatients referred to our department after an acute (type A or B) aortic dissection were prospectively included in a cohort between September 2012 and October 2017. CPET was performed once optimal blood pressure control was obtained. Clinical follow‐up was done after CPET for new aortic event and major cardio‐vascular events (MCE) not directly related to the aorta.ResultsAmong the 165 patients who underwent CPET, no adverse event was observed during exercise testing. Peak oxygen pulse was 1.46(1.22‐1.84) mlO2/beat, that is, 97 (83–113) % of its predicted value, suggesting cardiac exercise limitation in a population under beta blockers (92% of the population). During a follow‐up of 39(20‐51) months from CPET, 42 aortic event recurrences and 22 MCE not related to aorta occurred. Low peak oxygen pulse (<85% of predicted value) was independently predictive of aortic event recurrence, while low peak oxygen uptake (<70% of predicted value) was an independent predictor of MCE occurrence.ConclusionCPET is safe in postaortic dissection patients should be used to not only to personalize exercise rehabilitation, but also to identify those patients with the highest risk for new aortic events and MCE not directly related to aorta.  相似文献   
87.
The aim of our study is to investigate whether single-nucleotide dystrophin gene (DMD) variants associate with variability in cognitive functions in healthy populations. The study included 1240 participants from the Erasmus Rucphen family (ERF) study and 1464 individuals from the Rotterdam Study (RS). The participants whose exomes were sequenced and who were assessed for various cognitive traits were included in the analysis. To determine the association between DMD variants and cognitive ability, linear (mixed) modeling with adjustment for age, sex and education was used. Moreover, Sequence Kernel Association Test (SKAT) was used to test the overall association of the rare genetic variants present in the DMD with cognitive traits. Although no DMD variant surpassed the prespecified significance threshold (P<1 × 10−4), rs147546024:A>G showed strong association (β=1.786, P-value=2.56 × 10−4) with block-design test in the ERF study, while another variant rs1800273:G>A showed suggestive association (β=−0.465, P-value=0.002) with Mini-Mental State Examination test in the RS. Both variants are highly conserved, although rs147546024:A>G is an intronic variant, whereas rs1800273:G>A is a missense variant in the DMD which has a predicted damaging effect on the protein. Further gene-based analysis of DMD revealed suggestive association (P-values=0.087 and 0.074) with general cognitive ability in both cohorts. In conclusion, both single variant and gene-based analyses suggest the existence of variants in the DMD which may affect cognitive functioning in the general populations.  相似文献   
88.
This study is an attempt to unify the evaluation of patients with well-differentiated thyroid cancer after ablative therapy. As such, serum thyroglobulin determinations on and off thyroid hormone (T4) therapy and iodine 131 total body scans were examined in 53 patient studies. No metastases were found in patients whose thyroglobulin value was undetectable (< 1 ng/ml). Values during T4 therapy that were detectable, even as low as 4.2 ng/ml, were occasionally associated with metastases. After T4 withdrawal, thyroglobulin value and scan were obtained. Neither metastasis nor clinically detectable cancer was found in patients whose thyroglobulin value was less than 10 ng/ml while off T4. Conversely, a value greater than 10 ng/ml was often associated with documented metastases even when the scan was negative. In summary, a thyroglobulin value less than 1 ng/ml during T4 therapy or less than 10 ng/ml off T4 therapy suggests successful therapy and a routine scan could be avoided unless clinically indicated. However, a value greater than 10 ng/ml suggests the presence of metastasis despite a negative scan. Thyroglobulin determination substantially improves the management of these patients.  相似文献   
89.
Adults and children have differences in their susceptibility to schistosomiasis. The relative influences of age-dependent innate resistance and acquired immunity in the differences between susceptibility to schistosomiasis are difficult to assess in humans. Therefore, we exposed juvenile and adult female rhesus monkeys to primary infection with Schistosoma mansoni. In contrast to the adult animals, the juvenile rhesus monkeys had low levels of interleukin (IL)-4 and IL-5 production by peripheral blood mononuclear cells after schistosome infection, as well as lower levels of parasite-antigen-specific antibody (IgG, IgM, and IgA) responses, and produced limited antigen-specific or total IgE. Juvenile animals had statistically nonsignificant increased worm burdens and tissue or fecal egg counts, compared with that of adults, whereas circulating schistosome antigens were significantly higher in infected juvenile monkeys. These results suggest that juvenile rhesus monkeys have reduced type 2 cytokine responses after primary schistosome infections and perhaps are more susceptible to parasite infection.  相似文献   
90.
Duodenal ulcer has not been observed in full-heritage Pima Indians, while gastric cancer is relatively frequent. To investigate possible underlying factors for this phenomenon, we determined gastric acid output, gastric emptying rate, and plasma levels of gastrin, pepsinogen I, and pepsinogen II in apparently healthy Pima Indian and in Caucasian controls. The Pimas had significantly lower basal and stimulated outputs of gastric acid and higher fasting and postprandial plasma gastrin concentrations than the caucasians. Plasma pepsinogen I levels were similar in the two groups, but plasma pepsinogen II was significantly higher and the ratio of pepsinogen I to pepsinogen II was significantly lower in the Pima Indians. In addition, gastric emptying of an acaloric liqid meal was significantly delayed in the Pimas. The results suggest that the absence of duodenal ulcer in Pima Indians may be related to low gastric acid production and aslow rate of gastric emptying in this population. The associated findings of hypergastrinemia, hyperpepsinogenemia II, and a low ratio of pepsinogen I to pepsinogen II suggest that the hypochlorhydria may reflect an increased pervalence of chronic gastritis in full-heritage Pima Indians. This, in turn, could represent a risk factor for the development of gastric cancer in this population.Supported in part by research Contract 1-Am-6-2219 and grant AM 13233 from the National Institutes of Health, Bethesda, Maryland  相似文献   
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