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31.
Objective: To assess the effect of prophylactic corticosteroids administration at 37 weeks before term elective cesarean section (CS) in reducing neonatal respiratory morbidity and admission to neonatal intensive care unit (NICU).

Methods: This randomized trial was conducted focusing on women subjected to term elective CS. Women who were eligible for the study were divided into two groups. At 37 weeks' gestation; study group received two intramuscular doses of 12?mg dexamethasone 24?h apart, while the control group given the usual care without steroids. Outcome measures were adverse neonatal respiratory outcomes (respiratory distress syndrome (RDS) and transient tachypnea of the newborn (TTN)) and rates of admission to NICU.

Results: Neonates in the treatment group had lower overall incidence of respiratory distress morbidity 7.9% versus 23% when compared to the control group. The main morbidity was TTN (7% in study versus 19.6% in control group). There was significantly lower incidence of both mild and moderate degrees of respiratory distress in the study group (7 and 0.9%, respectively) compared to 17 and 5.3% in the control group. The most significant benefit of steroid administration was noted in those babies 37–37+6 weeks.

Conclusion: Antenatal administration of steroids at 37 weeks appears to be beneficial in reducing neonatal respiratory morbidity in women undergoing elective term CS.  相似文献   

32.
Two simple, sensitive, and rapid spectrofluorimetric methods were developed and validated for the determination of albendazole. The first method (method I) was based on the quenching effect of albendazole on the native fluorescence of erythrosine B. The fluorescence intensity was measured at 554 nm after extraction at 527 nm. In the second method (method II) the drug was reacted with lanthanum(iii) ions to form a metal complex, which was measured at 340 nm after excitation at 295 nm. The suitable pH was 3.4 (Teorell–Stenhagen buffer) and pH 5.5 (phosphate buffer solution), for method I and II, respectively. The influence of experimental factors on the fluorescence intensity of the reaction products was investigated and optimized. The linear concentration ranges were 0.2–3.5 and 0.06–0.90 μg mL−1, with detection limits of 0.049 and 0.019 μg mL−1 for method I and II, respectively. ICH guidelines were followed for validation of the developed procedures, and the results were acceptable. The Gibb''s free energy change of the reactions was −24.6 and −27.5 kJ mol−1 for method I and II, respectively. These negative values indicated the high feasibility of these reactions at ambient temperature. The proposed procedures were applied successfully for the determination of albendazole in commercial dosage forms and spiked human plasma. The results showed high precision, accuracy and recovery of the reported methods without any significant interference from pharmaceutical excipients or plasma components.

Complexation of albendazole with erythrosine B quench the native fluorescence of the dye while complexation of the drug with lanthanum (iii) ions enhance the fluorescence of the drug.  相似文献   
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34.
Poly(methacrylic acid) (P(MAA)), poly(acrylamide) (P(AAm)) and poly(3-acrylamidopropyltrimethyl ammonium chloride) (P(APTMACl)) were synthesized as anionic, neutral and cationic hydrogels, respectively. The synthesized hydrogels have the ability to be used as absorbents for the removal of selected heavy metal ions such as Cu2+, Co2+, Ni2+ and Zn2+ from aqueous media. Absorption studies revealed that the absorption of metal ions by the hydrogels followed the order Cu2+ > Ni2+ > Co2+ > Zn2+. For the mechanism of absorption, both Freundlich and Langmuir absorption isotherms were applied. Metal ion entrapped hydrogels were treated using an in situ chemical reduction method in order to convert the metal ions into metal nanoparticles for the synthesis of hybrid hydrogels. The synthesis and morphology were confirmed using FT-IR and SEM, while the absorbed metal amounts were measured using TGA and AAS. The hybrid hydrogels were further used as catalysts for the reduction of macro (methylene blue, methyl orange and congo red) and micro (4-nitrophenol and nitrobenzene) pollutants from the aqueous environment. The catalytic performance and re-usability of the hybrid hydrogels were successfully investigated.

Poly(methacrylic acid) (P(MAA)), poly(acrylamide) (P(AAm)) and poly(3-acrylamidopropyltrimethyl ammonium chloride) (P(APTMACl)) were synthesized as anionic, neutral and cationic hydrogels respectively.  相似文献   
35.
Both qualitative and quantitative changes in mitochondrial DNA (mtDNA) have been implicated in the pathogenesis of diabetes mellitus. In this study, we investigate whether peripheral blood mtDNA (pb-mtDNA) is decreased and if there is any relation between its content and the parameters of both insulin resistance and secretion in offspring of diabetic subjects. The pb-mtDNA content was measured by real time polymerase chain reaction with mitochondrial- specific fluorescent probe, normalized by a nuclear DNA, 28S rRNA gene, in 42 offspring of type 2 diabetic patients and 12 age-, sex- and body mass index (BMI)-matched normal subjects. The correlations between pb-mtDNA content and the parameters of insulin resistance and secretion were studied. Our results indicated that the level of pb-mtDNA was lower in offspring of diabetic subjects than in control subjects (1230 +/- 0.05 vs. 1513 +/- 0.02 in the offspring and control subjects, respectively, P < 0.05). Also, pb-mtDNA content was significantly correlated with logarithmically transformed insulin sensitivity index (r = 0.5, P < 0.05), fasting C-peptide (r = -0.8, P < 0.05), acute insulin response (r = -0.8, P < 0.05) and late insulin response (r = -0.7, P < 0.05) in offspring of diabetic subjects. In conclusion, quantitative mtDNA status might be a hereditary factor associated with type 2 diabetes and is correlated negatively with indexes of insulin resistance and insulin secretion in offspring of diabetic patients. So, pb-mtDNA content could serve as an indicator of insulin sensitivity and insulin secretion in those subjects.  相似文献   
36.
Using of bio-wastes in dye adsorption is one of the greenest influential applied techniques for the removal of dyestuff from the industrial effluents and it considered as waste management. In the current study, banana peel waste (BPW) was used as an inexpensive and eco-friendly adsorbent for methylene blue (MB) dye. Mechanical pretreatment of BPW was carried out and followed by biological activation using Rhizopus microspores. MB dye was adsorbed by mechanically pretreated BPW (mBPW) by 31%. Moreover, the day nine fermented BPW fibers (mbBPW) is the best time for R. microspores to complete activation, where adsorption ratio reached to about 96.5%. Likewise, enzymes activity was recorded the highest activity after this period of fermentation, where enzymes activity of cellulase, xylanase, lignin peroxidase, poly phenol oxidase and laccase were 0.75, 0.68, 0.38, 0.55 and 0.32 U/ml, respectively. The FT-IR, SEM and BET were used to observe the effect of treatment on the BPW. Otherwise, the kinetics study is illustrated that the adsorption of MB with mbBPW fitted with pseudo-first-order kinetic models. However, the adsorption parameters indicated that the Langmuir model is better to describe the adsorption of dye with excellent maximum adsorption capacity 991 mg/g. In conclusion, biologically activated BPW is very efficient for dye adsorption as well as waste management.  相似文献   
37.
Hepatitis C Virus (HCV) is a major etiological agent of chronic hepatitis, cirrhosis and hepatocellular carcinoma. Fas-mediated apoptosis is the major cause of hepatocyte damage during liver disease. The present work was performed to study the fas system (Fas-FasL and soluble Fas) in chronic hepatitis C infection. Also, to correlate the degree of liver cell damage with the Fas system. The study was carried out on 45 patients positive for HCV RNA by nested RT-PCR in addition to 13 HCV negative control subjects. Wedge liver biopsies samples were obtained from patients and controls during abdominal operations for determination of cellular expression of Fas and Fas-L on hepatocytes and infiltrating lymphocytes respectively by flow cytometry. Histological activity index (HAI) was determined in chronic HCV patients. Also blood samples were taken from patients and controls for determination of sFas. There was statistically insignificant difference in Fas expression in hepatocytes of patients (P?=?0.34) in comparison to control. Meanwhile, there was a statistically significant decrease in FasL expression in patients compared to control (P< 0.001) and statistically significant increase in soluble Fas in patients compared to control (P < 0.001). The HAI of liver fibrosis for all patients were within mild score with mean ± SD 4 ± 0.5. From this study, we could conclude that Fas system is one of the important pathways regulating the response to HCV infection. Increased serum sFas in HCV patients is accompanied by down-regulation of Fas/Fas-L expression resulting in inhibition of apoptosis in liver cells as a process for elimination of virus infected cells and this may ultimately leads to chronicity of the disease.  相似文献   
38.
Objectives: To identify and test the antibiotic susceptibility of nosocomial coliform bacilli and investigate the presence of oqxA and oqxB genes among the multidrug-resistant (MDR) phenotypes. Methods: One hundred and twenty different healthcare-associated infection samples were collected. Coliform bacilli were isolated, identified by conventional methods, and then antibiotic susceptibility tests were done using the VITEK2 system and disk diffusion methods. OqxAB operon was identified using a conventional PCR-based technique. oqxA and oqxB genes were compared between MDR Klebsiella pneumonia (K. pneumonia) phenotypes and MDR Escherichia coli (E. coli) phenotypes. Besides, oqxAB operons were compared between phenotypes of K. pneumonia and E. coli isolates. Results: Seventy coliform bacilli were isolated with the predominance of K. pneumonia and E. coli. Besides, 82.1% of K. pneumonia strains and 53.3% of E. coli isolates were MDR phenotypes. Significant more oqxB genes alone were found in MDR E. coli than that in MDR K. pneumoniae phenotypes (χ2=10.160, P=0.003). OqxAB operon was significantly more in MDR phenotypes of E. coli than that in the susceptible phenotypes (P<0.001). There was significantly less of this operon in susceptible E. coli isolates than that in susceptible K. pneumoniae isolates (P<0.001). OqxAB positive isolates that were also resistant to fluoroquinolones, tetracycline, trimethoprim, and chloramphenicol, most probably suggested functional pumps. Conclusions: MDR coliform bacilli are strongly implicated in healthcare-associated infection. Attention should be paid to the presence of oqxAB pump, as an important mechanism in the development of resistance against many antimicrobials because it contributes to co-resistance with other categories; therefore, this pump could be a good target for efflux pump inhibitors.  相似文献   
39.
ObjectiveThe objective of this study was to determine the acceptance of a coronavirus disease 2019 (COVID-19) vaccine among the general adult population in Kuwait and assess its determinants.Subjects and MethodsA web-based cross-sectional study was conducted by enrolling adults living in Kuwait (n = 2,368; aged ≥21 years). Acceptance of a COVID-19 vaccine was inferred if participants indicated that they “definitely or probably will accept vaccination against COVID-19 once a vaccine is available.” Associations were explored by applying a modified Poisson regression to estimate and infer adjusted prevalence ratios (aPR) and their 95% confidence intervals (CI).ResultsIn total, 53.1% (1,257/2,368) of the participants were willing to accept a COVID-19 vaccine once available. Male subjects were more willing to accept a COVID-19 vaccine than females (58.3 vs. 50.9%, p < 0.001). Subjects who viewed vaccines in general to have health-related risks were less willing to accept vaccination (aPR = 0.39, 95% CI: 0.35–0.44). Moreover, participants who previously received an influenza vaccine were more likely to accept a COVID-19 vaccine (aPR = 1.44, 95% CI: 1.31–1.58). Willingness to get vaccinated against COVID-19 increased as the self-perceived chances of contracting the infection increased (p < 0.001).ConclusionOverall, 53.1% of the study participants demonstrated willingness to get vaccinated against COVID-19. We found several factors influencing the level of acceptance. Since vaccination appears to be an essential preventive measure that can halt the COVID-19 pandemic, factors relating to low vaccine acceptance need to be urgently addressed by public health strategies.  相似文献   
40.
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