Application of vacuum-assisted closure in seawater-immersed wound treatment under different negative pressures.

The therapeutic effect of vacuum-assisted closure (VAC) has been confirmed in many types of complex wounds, but there are few relevant reports regarding seawater-immersed wounds. The aim of this study was to determine the effect of VAC on seawater-immersed wound healing under different negative pressures and explore the optimal negative pressure value. Four purebred miniature pigs were used as the experimental animal models. Four acute, symmetrical wounds were made on each side of the spine and designated as the experimental group (wounds with 2 h of seawater immersion) and the control group (wounds without seawater immersion). Wounds were divided into a conventional dressing group and 3 further groups with different VAC therapies (negative pressure at either 120, 180, or 240 mmHg). The extent of wound healing, and speed of granulation growth and re-epithelialization were measured. Bacterial flora distribution in the wounds was observed, and fibronectin levels in the exudate of the wounds were tested. Results showed that seawater immersion aggravated wound injury and that VAC therapy with 180 mmHg negative pressure induced the fastest epidermis migration, obvious edema elimination, significant capillary proliferation, and the highest level of fibronectin, and that in wounds, the proportion of Gram-negative bacteria tended to decrease and that of Gram-positive bacteria tended to increase. Our results show that VAC promotes seawater-immersed wound healing and that 180 mmHg negative pressure may be optimal for wound healing.

The tumour necrosis factor-α-238A allele increases the risk of chronic HBV infection in European populations.

Tumour necrosis factor-α (TNF-α) plays a pivotal role in viral clearance and host immune response to hepatitis B virus (HBV) infection, of which the production capacity in individuals is demonstrated to be influenced by a single nucleotide polymorphism within the promoter region of TNF-α genes. However, there have been conflicting results reported in previous studies on TNF-α-238 and TNF-α-863 gene promoter polymorphisms in chronic HBV infection. To derive a more precise estimation of their relationship, we searched Pubmed (January, 1966-August, 2010) and China Biological Medicine Database (January, 1978-August, 2010) and carried out a meta-analysis involving nineteen studies that included 5245 chronic HBV infection cases and 3181 controls describing G238A genotypes, and eleven studies totalling 3576 cases and 2044 controls describing C863A genotypes. The overall meta-analysis did not suggest significant associations of TNF-α-238 and TNF-α-863 gene promoter polymorphisms with chronic HBV infection. However, in subgroup analysis by ethnicity, it indicated that TNF-α-238A allele carriers (GA + AA) in European populations had an increased risk of developing chronic HBV infection (OR = 2.22, 95% CI: 1.07-4.58, P = 0.032; OR = 4.46, 95% CI: 1.75-11.38, P = 0.002, respectively), when compared with spontaneous recovered and healthy populations, respectively. However, no significant associations were found in Asian populations in all genetic models. So, we draw the conclusion that the TNF-α-238A allele may increase the risk of chronic HBV infection in European populations.

Tumour necrosis factor-α-857T allele reduces the risk of hepatitis B virus infection in an Asian population.

Tumour necrosis factor-α (TNF-α) plays a pivotal role in hepatitis B virus (HBV) clearance and host immune response determining the chronicity of HBV infection. However, studies of the association between TNF-α-857 polymorphism and chronic HBV infection have reported conflicting results. So a meta-analysis was carried out to draw a more precise conclusion. Pubmed (January, 1966-March, 2011) and the China Biological Medicine Database (January, 1978-March, 2011) were searched using the keywords TNF-α gene polymorphism in combination with HBV infection without language restriction. Fourteen studies including 4929 chronic HBV infection cases and 2702 controls describing the C857T genotype were included in the meta-analysis. All fourteen studies focussed on an Asian population. The overall meta-analysis suggested that TNF-α-857T allele reduced the risk of chronic HBV infection in the Asian population (OR = 0.82, 95% CI: 0.71-0.95, P = 0.008) when compared with a spontaneously recovered population. In the sensitivity analyses of the groups obeying Hardy-Weinberg equilibrium (HWE), without the largest study population and without the smallest study population, a similar association was revealed (OR = 0.81, 95% CI: 0.68-0.98, P = 0.043; OR = 0.77, 95% CI: 0.68-0.87, P = 0.0001; OR = 0.81, 95% CI: 0.70-0.95, P = 0.009, respectively). However, when compared with a healthy population, no significant association was found in the Asian population in all groups. So, we draw the conclusion that the TNF-α-857T allele reduces the risk of chronic HBV infection in this Asian population.

Low glycaemic index diets as an intervention for obesity: a systematic review and meta-analysis.

OBJECTIVES: Low glycaemic index (GI) diets may aid in weight loss by reducing postprandial blood glucose excursions, leading to more stable blood glucose concentrations and therefore a reduction in hunger. To test this hypothesis, we conducted a systematic review and meta-analysis of randomized controlled trials comparing low GI diets with other diet types. METHODS: We included 101 studies involving 109 study arms and 8,527 participants. We meta-analysed the studies using a random-effects model and conducted subgroup analyses and meta-regression based on control diet, blood glucose control, baseline BMI and dietary GI. RESULTS: Low GI diets resulted in small but significant improvements in body weight, BMI, LDL and total cholesterol overall, although no individual control diet was significantly different from low GI diets. Studies in people with normal blood glucose who achieved a difference in GI of 20 points or more resulted in a larger reduction in body weight (SMD = -0.26; 95% CIs [-0.43, -0.09]), and total cholesterol (SMD = -0.24; 95% CIs [-0.42, -0.05]) than studies that only achieved a smaller reduction in GI. CONCLUSIONS: Low GI diets, especially diets achieving a substantial decrease in GI, were moderately effective in lowering body weight. However, efforts should be made to increase compliance with low GI diets, in order for them to be effective in people with overweight and obesity.

Effect of gestational subclinical hypothyroidism on early neurodevelopment of offspring.

OBJECTIVE: To evaluate the effects of gestational subclinical hypothyroidism (SCH) on early neurodevelopment of offspring. STUDY DESIGN: A prospective study included 106 infants born to mothers with gestational SCH and 106 infants born to mothers who were euthyroid during pregnancy. The neurodevelopment of 12 to 24-month-old infants was assessed and compared using the Gesell developmental test (revised version). RESULTS: Infants born to mothers with gestational SCH and those born to euthyroid mothers had similar scores on the Gesell development test. No correlations were observed between maternal TSH concentration and Gesell developmental test scores of offspring. Infants born to mothers who had gestational SCH during the first trimester specifically and those born to euthyroid mothers had similar scores on the Gesell development test. No significant correlations were detected between maternal TSH concentration during the first trimester and offspring neurodevelopment. CONCLUSIONS: No detectable neurodevelopment deficit was observed in offspring up to 24 months old from mothers who had gestational SCH.

Mechanisms of artemisinin resistance in the rodent malaria pathogen Plasmodium yoelii.

Artemisinin and its derivatives are important new antimalarials which are now used widely in Southeast Asia. Clinically relevant artemisinin resistance has not yet been reported but is likely to occur. In order to understand how the malaria parasite might become resistant to this drug, we studied artemisinin resistance in the murine malaria parasite Plasmodium yoelii. The artemisinin-resistant strain (ART), which is approximately fourfold less sensitive to artemisinin than the sensitive NS strain, accumulated 43% less radiolabeled drug in vitro (P < 0.01). Within the parasite, the drug appeared to react with the same parasite proteins in both strains. The translationally controlled tumor protein, one of the artemisinin target proteins, did not differ between the strains. No DNA sequence difference was found, but the resistant strain was found to express 2.5-fold-more protein than the sensitive strain (P < 0.01). Thus, the phenotype of artemisinin resistance in P. yoelii appears to be multifactorial.

A multilocus genotypic analysis of Cryptosporidium meleagridis.

Cryptosporidium meleagridis is a common cause of cryptosporidiosis in birds. In addition, recent reports have described the parasite as an etiologic agent of cryptosporidiosis in both immunocompetent and immunocompromised humans. Therefore, it is important to genetically characterize isolates of C. meleagridis from different hosts and geographic areas, and to develop molecular tools to differentiate isolates from various hosts or areas. In this study, a total of 11 isolates of Cryptosporidium meleagridis from both human and avian hosts were examined at three genetic loci: the small-subunit rRNA, 60-kDa glycoprotein precursor, and 70-kDa heat shock protein genes. Two genotypes of C. meleagridis were seen at the small-subunit rRNA locus. These differed from each other by the presence or lack of a heterogeneous copy of the gene and an ATT repeat. The 60-kDa glycoprotein precursor gene divided these eleven isolates of C. meleagridis into six genotypes with high sequence diversity between groups. The highest genetic heterogeneity, however, was seen at the 70-kDa heat shock protein locus, and was primarily present at the 3' end of the gene. This heterogeneity separated eight isolates of C. meleagridis into six genotypes. These data could be useful in the development of molecular tools to promote understanding of the transmission of C. meleagridis in humans.

Genetic polymorphism among Cryptosporidium parvum isolates: evidence of two distinct human transmission cycles.

We report the results of molecular analysis of 39 isolates of Cryptosporidium parvum from human and bovine sources in nine human outbreaks and from bovine sources from a wide geographic distribution. All 39 isolates could be divided into either of two genotypes, on the basis of genetic polymorphism observed at the thrombospondin-related adhesion protein (TRAP-C2) locus. Genotype 1 was observed only in isolates from humans. Genotype 2, however, was seen in calf isolates and in isolates from a subset of human patients who reported direct exposure to infected cattle or consumed items thought to be contaminated with cattle faces. Furthermore, experimental infection studies showed that genotype 2 isolates were infective to mice or calves under routine laboratory conditions, whereas genotype 1 isolates were not. These results support the occurrence of two distinct transmission cycles of C. parvum in humans.