Closure techniques for fetoscopic access sites in the rabbit at mid-gestation.
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Operative fetoscopy may be limited by its relatively high associated risk of preterm prelabour rupture of membranes. The objective of this study was to study closure techniques of the access site for fetoscopy in the mid-gestational rabbit. A total of 32 does (288 amniotic sacs) at 22 days gestational age (GA; term = 32 days) underwent 14 gauge needle fetoscopy, by puncture through surgically exposed amnion. Entry site was randomly allocated to four closure technique groups: myometrial suture (n = 14), fibrin sealant (n = 15), autologous maternal blood plug (n = 13), collagen plug (n = 14); 16 sacs were left unclosed (positive controls), and the unmanipulated 216 sacs were negative controls. Membrane integrity, presence of amniotic fluid and fetal lung to body weight ratio (FLBWR) were evaluated at 31 days GA. Following fetoscopy without an attempt to close the membranes, amniotic integrity was restored in 41% of cases (amniotic integrity in controls 94%; P = 0.00001). When the access site was surgically closed, the amnion resealed in 20-44% of cases, but none of the tested techniques was significantly better than the others or than positive controls. Permanent amniotic disruption was associated with a significantly lower FLBWR in all groups. In conclusion, the rate of fetoscopy-induced permanent membrane defects in this model did not improve by using any of the closure techniques tested here. (+info)
Evaluation of malaria surveillance using retrospective, laboratory-based active case detection in four southwestern states, 1995.
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The global resurgence of malaria has raised concerns of the possible reintroduction of indigenous transmission in the United States. The Centers for Disease Control and Prevention's National Malaria Surveillance System, using data supplied by state and local health departments (SLHDs), is maintained to detect local malaria transmission and monitor trends in imported cases. To determine the completeness of reporting of malaria cases to SLHDs, cases identified by local surveillance systems were compared with those identified through active case detection conducted at all laboratories that receive clinical specimens from 11 metropolitan areas in Arizona, California, New Mexico, and Texas. Of the 61 malaria cases identified through either local surveillance or active case detection, 43 (70%) were identified by SLHDs (range by metropolitan area = 50-100%) and 56 (92%) through active case detection. High percentages of cases were identified by SLHDs in New Mexico (80%) and San Diego County (88%), where laboratories are required to send positive blood smears to the SLHD laboratory for confirmation. Completeness of reporting, calculated using the Lincoln-Peterson Capture-Recapture technique, was 69% for SLHD surveillance systems and 89% for laboratory-based active case detection. The high percentage of cases identified by the 11 SLHDs suggests that the National Malaria Surveillance System provides trends that accurately reflect the epidemiology of malaria in the United States. Case identification may be improved by promoting confirmatory testing in SLHD laboratories and incorporating laboratory-based reporting into local surveillance systems. (+info)
Establishing a laboratory for surveillance of invasive bacterial infections in a tertiary care government hospital in a rural province in the Philippines.
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A clinical bacteriologic laboratory was established in a tertiary care government hospital in The Philippines, where expert bacteriologic laboratories do not usually exist at this level of health care. The laboratory was jointly established by the Research Institute for Tropical Medicine (RITM) (Manila, The Philippines) and the National Public Health Institute (KTL) (Helsinki, Finland). The laboratory was planned, its personnel were trained, and its functioning was continuously supported by the RITM and KTL. The following aspects were of utmost importance in establishing the laboratory and launching its work: 1) the support of the RITM bacteriologic laboratory, with back-up and consultations from KTL; 2) creation and maintenance of personal contacts between clinicians and laboratory staff with an emphasis on clinical relevance and rapid reporting of laboratory results; 3) the consideration of the quality aspects of the work from the start; and 4) keen follow-up of the bacteriologic results and their clinical significance and use, of practical laboratory work, and of quality assurance aspects. In the first two years of its operation, the laboratory identified Streptococcus pneumoniae and Haemophilus influenzae as the most important causes of severe pneumonia, sepsis or meningitis in children less than two years of age, and Salmonella typhi as the most frequent significant isolate from the blood cultures, being found most often in school age children and young adults. (+info)
Prevention of cerebral malaria in children in Papua New Guinea by southeast Asian ovalocytosis band 3.
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Southeast Asian ovalocytosis (SAO) occurs at high frequency in malarious regions of the western Pacific and may afford a survival advantage against malaria. It is caused by a deletion of the erythrocyte membrane band 3 gene and the band 3 protein mediates the cytoadherence of parasitized erythrocytes in vitro. The SAO band 3 variant may prevent cerebral malaria but it exacerbates malaria anemia and may also increase acidosis, a major determinant of mortality in malaria. We undertook a case-control study of children admitted to hospital in a malarious region of Papua New Guinea. The SAO band 3, detected by the polymerase chain reaction, was present in 0 of 68 children with cerebral malaria compared with six (8.8%) of 68 matched community controls (odds ratio = 0, 95% confidence interval = 0-0.85). Median hemoglobin levels were 1.2 g/dl lower in malaria cases with SAO than in controls (P = 0.035) but acidosis was not affected. The remarkable protection that SAO band 3 affords against cerebral malaria may offer a valuable approach to a better understanding of the mechanisms of adherence of parasitized erythrocytes to vascular endothelium, and thus of the pathogenesis of cerebral malaria. (+info)
PCR and blood culture for detection of Escherichia coli bacteremia in rats.
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Critically ill patients often develop symptoms of sepsis and therefore require microbiological tests for bacteremia that use conventional blood culture (BC) techniques. However, since these patients frequently receive early empirical antibiotic therapy before diagnostic procedures are completed, examination by BC can return false-negative results. We therefore hypothesized that PCR could improve the rate of detection of microbial pathogens over that of BC. To test this hypothesis, male Wistar rats were challenged intravenously with 10(6) CFU of Escherichia coli. Blood was then taken at several time points for detection of E. coli by BC and by PCR with E. coli-specific primers derived from the uidA gene, encoding beta-glucuronidase. In further experiments, cefotaxime (100 or 50 mg/kg of body weight) was administered intravenously to rats 10 min after E. coli challenge. Without this chemotherapy, the E. coli detection rate decreased at 15 min and at 210 min after challenge from 100% to 62% of the animals with PCR and from 100% to 54% of the animals with BC (P, >0.05). Chemotherapy decreased the E. coli detection rate at 25 min and at 55 min after challenge from 100% to 50% with PCR and from 100% to 0% with BC (P, <0.05). Thus, at clinically relevant serum antibiotic levels, PCR affords a significantly higher detection rate than BC in this rat model. The results suggest that PCR could be a useful adjunct tool supplementing conventional BC techniques in diagnosing bacteremia. (+info)
Effects of dichloroacetate infusion on human skeletal muscle metabolism at the onset of exercise.
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This study investigated whether dichloroacetate (DCA) decreases the reliance on substrate level phosphorylation during the transition from rest to moderate-intensity exercise in humans. Nine subjects cycled at approximately 65% of maximal oxygen uptake (VO(2 max)) after a saline or DCA (100 mg/kg body wt) infusion, with muscle biopsies taken at rest and at 30 s and 2 and 10 min of exercise. DCA infusion increased pyruvate dehydrogenase (PDH) activation at rest (4.0 +/- 0.3 vs. 0.9 +/- 0.1 mmol. kg wet wt(-1). min(-1)) and at 30 s (3.6 +/- 0.2 vs. 2.5 +/- 0.4 mmol. kg(-1). min(-1)) of exercise. As a result, acetyl-CoA (45.9 +/- 5.9 vs. 11.3 +/- 1.5 micromol/kg dry wt) and acetylcarnitine (13.1 +/- 1.0 vs. 1.6 +/- 0.3 mmol/kg dry wt) were markedly increased by DCA infusion at rest. These differences were maintained at 30 s and 2 min for both acetyl-CoA and acetylcarnitine. Resting muscle lactate and phosphocreatine (PCr) were not different between trials, but DCA infusion resulted in lower lactate accumulation throughout exercise, especially at 2 min (21.6 +/- 3.1 vs. 44.6 +/- 8.0 mmol/kg dry wt). PCr utilization in the initial 30 s (16.9 +/- 0.4 vs. 31.7 +/- 2.6 mmol/kg dry wt) and 2 min (27.8 +/- 4.7 vs. 45.1 +/- 2.6 mmol/kg dry wt) of exercise was decreased with DCA. This resulted in a lower accumulation of free inorganic phosphate at 30 s (25.4 +/- 2.0 vs. 36.4 +/- 2.8 mmol/kg dry wt) and 2 min (34.6 +/- 4.7 vs. 50.5 +/- 2.2 mmol/kg dry wt) with DCA and decreased glycogenolysis over 10 min. The data from this study support the hypothesis that increased provision of substrate by DCA infusion increases oxidative metabolism during the rest-to-work transition, resulting in decreased PCr utilization and an improved cellular energy state at the onset of exercise. The transitory improvement in energy state decreased glycogenolysis and lactate accumulation during moderate-intensity exercise. (+info)
Glucose turnover and adipose tissue lipolysis are insulin-resistant in healthy relatives of type 2 diabetes patients: is cellular insulin resistance a secondary phenomenon?
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To elucidate potential mechanisms for insulin resistance occurring early in the development of type 2 diabetes, we studied 10 young healthy individuals, each with two first-degree relatives with type 2 diabetes, and 10 control subjects without known type 2 diabetic relatives. They were pairwise matched for age (35 +/- 1 vs. 35 +/- 1 years), BMI (23.6 +/- 0.6 vs. 23.1 +/- 0.4 kg/m2), and sex (four men, six women). Glucose turnover was assessed during a euglycemic clamp at two insulin levels (low approximately 20 mU/l; high approximately 90 mU/l), and abdominal subcutaneous adipose tissue (SAT) lipolysis and blood flow were concomitantly studied with microdialysis and 133Xe clearance. HbA1c was higher in patients with type 2 diabetic relatives than in control subjects (4.8 +/- 0.1 vs. 4.5 +/- 0.1%, P < 0.02), but fasting glucose, insulin, and C-peptide levels were similar. During the clamp, the insulin sensitivity index for glucose disposal was lower (P < 0.03) in relatives than in control subjects (low 12.0 +/- 1.6 vs. 18.1 +/- 1.4; high 9.4 +/- 0.8 vs. 12.9 +/- 0.6 [100 x mg x l x kg(-1) x mU(-1) x min(-1)]). This difference was partially attributed to slightly higher clamp insulin levels in the relatives (P < 0.03), suggesting an impaired rate for insulin clearance. SAT lipolysis measured as in situ glycerol release did not differ under basal conditions (2.0 +/- 0.2 vs. 2.1 +/- 0.2 micromol x kg(-1) x min(-1)), but the suppression during the insulin infusion was less marked in relatives than in control subjects (glycerol release: low 0.92 +/- 0.09 vs. 0.68 +/- 0.16; high 0.71 +/- 0.10 vs. 0.34 +/- 0.10 micromol x kg(-1) x min(-1); P < 0.03). Plasma nonesterified fatty acids also tended to be higher in relatives than in control subjects during the insulin infusion (NS). In contrast, in vitro experiments with isolated subcutaneous adipocytes displayed similar effects of insulin in relatives and control subjects with respect to both glucose uptake and antilipolysis. In conclusion, insulin action in vivo on both lipolysis and glucose uptake is impaired early in the development of type 2 diabetes. Since this impairment was not found in isolated adipocytes, it may be suggested that neural or hormonal perturbations precede cellular insulin resistance in type 2 diabetes. (+info)
Predicting malaria infection in Gambian children from satellite data and bed net use surveys: the importance of spatial correlation in the interpretation of results.
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In line with the renewed World Health Organization Global Malaria Control Strategy, we have advocated the use of satellite imagery by control services to provide environmental information for malaria stratification, monitoring, and early warning. To achieve this operationally, appropriate methodologies must be developed for integrating environmental and epidemiologic data into models that can be used by decision-makers for improved resource allocation. Using methodologies developed for the Famine Early Warning Systems and spatial statistics, we show a significant association between age related malaria infection in Gambian children and the amount of seasonal environmental greenness as measured using the normalized difference vegetation index derived from satellite data. The resulting model is used to predict changes in malaria prevalence rates in children resulting from different bed net control scenarios. (+info)