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Objective

Labetalol is often used in severe preeclampsia (PE). Hypotension, bradycardia and hypoglycemia are feared neonatal side effects, but may also occur in (preterm) infants regardless of labetalol exposure. We analyzed the possible association between intrauterine labetalol exposure and such side effects.

Study design

From 1 January 2003 through 31 March 2008, all infants from mothers suffering severe PE admitted to one tertiary care center were included. Severe PE was defined according to the International Society for the Study of Hypertension in Pregnancy (ISSHP) criteria. Infants exposed to labetalol in utero (labetalol infants) were compared with infants, who were not exposed to labetalol (controls). Neonatal records were reviewed for hypotension (RR < mean gestational age in weeks), bradycardia (heartrate < 100/min) and hypoglycaemia (glucose < 2.7 mmol/L) in the first 48 postnatal hours.

Results

Of 109 infants, 55 had been exposed to labetalol, whereas 54 were not (controls). Gestational age at delivery and birthweight were similar in both groups (31.8 vs. 32.8 weeks (p = 0.06) and 1510 vs. 1639 grams (p = 0.25), respectively for the labetalol vs. control group). Hypotension occurred significantly more in conjunction with labetalol exposure (16, (29.1%) vs. 4 (7.4%); p = 0.003), irrespective of the route of administration. Patent ductus arteriosus (PDA) was present in 9 (56%) of hypotensive labetalol infants compared to 1 (24%) infant in the hypotensive control group (NS). In a multivariate regression model, labetalol exposure, the need for intubation and PDA appeared independently associated with hypotension (P < 0.001). Hypoglycemia occurred in 26 (47.3%) of labetalol infants and in 23 (42.6%) of control infants (p = 0.62). Bradycardia occurred in 4 (7.3%) of labetalol infants and in 1 (1.9%) of control infants (p = 0.18). Hypoglycemia was more common in premature infants (n = 45 (48,9%) vs. n = 4 (23.5%), p = 0.05) in both labetalol and control infants.

Conclusion

Hypotension is more common after maternal labetalol exposure, regardless of the dosage and route of administration. The need for intubation and the presence of a PDA also play a role. Hypoglycemia is a very common finding in this population and is merely related to prematurity and independent of labetalol exposure as was the incidental occurrence of bradycardia. These findings on the neonatal side effects of maternal labetalol treatment in preeclampsia underline the importance of frequent blood glucose and blood pressure measurements in the first days of life, especially in intubated preterm infants with a PDA.  相似文献   
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BACKGROUND & AIMS: A less costly cancer surveillance method for Barrett's esophagus is desirable. The aim of this study was to compare nonendoscopic balloon cytology with biopsy and brush cytology for detecting dysplasia and carcinoma in patients with Barrett's esophagus. METHODS: Patients in a surveillance program underwent balloon cytology before endoscopy with biopsy and brush cytology. Results of cytology were compared with those of histology. RESULTS: Adequate columnar epithelium was obtained in 52 of 63 (83%) patients with balloon cytology and 59 of 61 (97%) with brush cytology. Balloon cytology obtained abnormal cells in 6 of 8 patients with adenocarcinoma, 2 of 2 patients with high-grade dysplasia, and 2 of 8 patients with low-grade dysplasia. Sensitivity of balloon cytology for high-grade dysplasia or carcinoma was 80% but only 25% for low-grade dysplasia. No patients without dysplasia or carcinoma had abnormal cells. Brush cytology was abnormal in all 11 patients with high-grade dysplasia or carcinoma but only 2 of 9 patients with low-grade dysplasia (sensitivity, 22%). Two of 39 patients without dysplasia had abnormal cells (specificity, 95%). Balloon cytology cost was sixfold less than endoscopy with biopsy. CONCLUSIONS: Balloon cytology detected 80% of patients with high-grade dysplasia or carcinoma when sampling was adequate. Brush cytology data suggest that a more abrasive balloon may improve balloon cytology sensitivity. The potential cost savings of balloon cytology compared with endoscopic cancer surveillance in Barrett's esophagus support further studies of this technique. (Gastroenterology 1997 Jun;112(6):1787-97)  相似文献   
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Changes in collateral blood flow, which sustains brain viability distal to arterial occlusion, may impact infarct evolution but have not previously been demonstrated in humans. We correlated leptomeningeal collateral flow, assessed using novel perfusion magnetic resonance imaging (MRI) processing at baseline and 3 to 5 days, with simultaneous assessment of perfusion parameters. Perfusion raw data were averaged across three consecutive slices to increase leptomeningeal collateral vessel continuity after subtraction of baseline signal analogous to digital subtraction angiography. Changes in collateral quality, Tmax hypoperfusion severity, and infarct growth were assessed between baseline and days 3 to 5 perfusion–diffusion MRI. Acute MRI was analysed for 88 patients imaged 3 to 6 hours after ischemic stroke onset. Better collateral flow at baseline was associated with larger perfusion–diffusion mismatch (Spearman''s Rho 0.51, P<0.001) and smaller baseline diffusion lesion volume (Rho −0.70, P<0.001). In 30 patients without reperfusion at day 3 to 5, deterioration in collateral quality between baseline and subacute imaging was strongly associated with absolute (P=0.02) and relative (P<0.001) infarct growth. The deterioration in collateral grade correlated with increased mean Tmax hypoperfusion severity (Rho −0.68, P<0.001). Deterioration in Tmax hypoperfusion severity was also significantly associated with absolute (P=0.003) and relative (P=0.002) infarct growth. Collateral flow is dynamic and failure is associated with infarct growth.  相似文献   
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Pulmonary function and nutritional status are important determinants of exercise capacity in patients with cystic fibrosis (CF). Studies investigating the effects of determinants, such as genotype or infection and inflammation, are scarce and have never been analysed in a multivariate longitudinal model. A prospective longitudinal cohort study was performed to evaluate whether genotype, chronic inflammation and infection were associated with changes in exercise capacity. Furthermore, we investigated whether exercise capacity can predict clinical outcome. 504 exercise tests of 149 adolescents with CF were evaluated. Maximal oxygen uptake corrected for body mass % predicted declined 20% during adolescence, and was associated with immunoglobulin (Ig)G levels and chronic Pseudomonas aeruginosa infection. A lower exercise capacity was associated with a higher mortality, steeper decline in pulmonary function and greater increase in IgG levels. Since a decline in exercise capacity during adolescence was negatively associated with IgG levels and chronic P. aeruginosa infection, these data emphasise the importance of prevention and treatment of chronic inflammation and infections in patients with CF. Furthermore, a lower exercise capacity was associated with a higher mortality rate, steeper decline in pulmonary function and higher increase in IgG levels with increasing age in adolescents with CF. This stresses the value of regular exercise testing for assessing prognosis in adolescents with CF.  相似文献   
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Lin  L; Londe  H; Janda  JM; Hanson  CV; Corash  L 《Blood》1994,83(9):2698-2706
Platelet concentrates (PC) may be infrequently contaminated with low levels of bacteria that can cause septicemia and death in patients receiving transfusion therapy. We evaluated the efficacy of a photochemical decontamination (PCD) technique using 8-methoxypsoralen (8-MOP) and long wavelength UV light (UVA) to inactivate bacteria in standard therapeutic PC. Twelve phylogenetically distinct pathogenic bacteria, 5 gram-positive and 7 gram-negative organisms, were seeded into PC to a final challenge dose ranging from 10(5) to 10(7) colony- forming units (CFU)/mL. Contaminated PC were treated with 8-MOP (5 micrograms/mL) and 5 J/cm2 of UVA, a PCD treatment regimen found to adequately preserve in vitro platelet function. Greater than 10(5) CFU/mL of all 5 gram-positive (Staphylococcus aureus, Streptococcus epidermidis, Streptococcus pyogenes, Listeria monocytogenes, and Corynebacterium minutissimum) and 2 of the gram-negative (Escherichia coli and Yersinia enterocolitica) organisms were inactivated. The remaining 5 gram-negative organisms were more resistant, with less than 10(1) to 10(3.7) CFU/mL inactivated under these conditions. The inactivation efficiency for this resistant group of gram-negative organisms was improved when PC were resuspended in a synthetic storage medium with reduced plasma protein concentration (15%) and an increased 8-MOP concentration (23.4 micrograms/mL). Illumination with 3 J/cm2 of UVA in this system inactivated greater than 10(5) CFU/mL of 4 resistant gram-negative organisms (Salmonella choleraesuis, Enterobacter cloacae, Serratia marcescens, and Klebsiella pneumoniae) and 10(4.1) CFU/mL of the most resistant gram-negative organism (Pseudomonas aeruginosa). This level of PCD treatment did not adversely affect in vitro platelet function. These results demonstrate that PCD using 8-MOP (5 to 23.4 micrograms/mL) effectively inactivated high levels of pathogenic bacteria in PC with adequate preservation of in vitro platelet properties.  相似文献   
68.
ObjectiveThe aim of this study was to identify the presence of antimicrobial activity in different organs/tissues (gills, blood, skin, liver, intestine, kidney, tissue and ovary) extract of snakehead fish Channa striatus.MethodsA total of 48 fractions from the organs and tissue extracts were obtained by solid-phase extraction and the fractions were assayed for antimicrobial activity. The screening of antimicrobial activity for all the fractions were tested against 8 human pathogens including Gram positive (Methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, Bacillus cereus) and Gram negative bacteria (Salmonella enteritidis, Shigella flexneri, Acinetobacter baumanni, Escherichia coli, Klebsiella pneumoniae) using the British Society for Antimicrobial Chemotherapy (BSAC) standardized disc susceptibility test method. The activity was measured in terms of zone of inhibition in mm.ResultsThe results indicated that, among the 8 organs/tissues tested only blood and gills extract fractions (40 and 60 % ACN fraction) showed inhibition against Escherichia coli and 60 % ACN fraction of gill extract showed inhibition against Salmonella enteritidis. Protein profile analysis by SDS-PAGE showed that antimicrobial activity of the partially purified blood and gill tissue extracts might be due to low molecular weight peptides.ConclusionsThe present study showed that, gill and blood extracts of Channa striatus can be a potential source of an antimicrobial protein for specific human pathogens.  相似文献   
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