C-reactive protein and diabetic retinopathy in Chinese patients with type 2 diabetes mellitus

AIM: To investigate the relationship between C-reactive protein (CRP) and diabetic retinopathy (DR) in a cohort of Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: Community-based observational cohort study. There were 1131 participants recruited from November 2009 to September 2011 in Desheng community in urban Beijing. Patients diagnosed T2DM were recruited and underwent a standardized evaluation consisting of a questionnaire, ocular and anthropometric examinations and laboratory investigation. The presence and severity of DR were assessed by seven fields 30° color fundus photographs. Subjects were then classified into groups with no DR, any DR, or vision-threatening DR. CRP was analyzed from serum of study subjects. RESULTS: A total of 1007 patients with T2DM were included for analysis, including 408 (40.5%) men and 599 (59.5%) women. The median CRP level was 1.5 mg/L for women and 1.1 mg/L for men (P=0.004, OR 0.37, 95% CI 0.18-0.74). After adjusting for possible covariates, higher levels of CRP were associated with lower prevalence of any DR (P=0.02, OR 0.55, 95% CI 0.35-0.89), but not associated with vision-threatening DR (P=0.62, OR 0.78, 95% CI 0.28-2.14). After stratification by sex, the inverse association between CRP and DR was found to be statistically significant in men (P=0.006, OR 0.35, 95% CI 0.16-0.73), but not in women (P=0.58, OR 0.88, 95% CI 0.29-1.16). CONCLUSION: The data drawn from a Chinese population with T2DM suggest that increasing CRP levels may be inversely associated with development of DR.     

Hepatitis TT virus infection in high-risk groups

Summary The novel hepatitis TT virus first described by a Japanese group has been reported to be parenterally transmitted and furthermore, to have been detected in patients with hepatitis of unknown etiology. Hence, in the present study its prevalence was investigated within groups at high risk for contracting blood-borne viruses, such as individuals with chronic liver disease, intravenous drug users and recipients of blood and blood products, as compared to voluntary blood donors and pregnant women. To that end, DNA was extracted from sera obtained from the respective patients and subjected to PCR using semi-nested primers. The frequency of TTV DNA detected within high risk groups, such as nine out of 50 patients with chronic non-A-to-G liver disease (18%), nine out of 98 hepatocellular carcinoma cases (9.2%), 17 out of 52 intravenous drug users (32.7%), 15 out of 80 thalassemia patients with multiple blood transfusions (18.8%) and three out of 31 prostitutes (9.7%) exceeded that among voluntary blood donors and pregnant women, which amounted to 14 out of 200 (7%) and seven out of 103 (6.8%), respectively. Additional molecular research should be performed in order to determine its short-, as well as long-term clinical significance.     

Socio-demographic and environmental factors associated with Aedes breeding places in Phuket, Thailand

This study aimed to determine the socio-demographic and environmental factors influencing potential breeding sites of the dengue vector in Phuket Province. Three hundred houses were recruited by cluster random sampling for larval inspection. Of all the types of water containers, a high proportion of tires and discarded items were infested by Aedes larva (42% and 32%, respectively). Due to the abundance of water tanks, jars for using water and discarded containers (1.7, 2.1, 0.8 per house), these were the main breeding sites (0.29, 0.35, and 0.28 infested containers per house, respectively). Buddhists' houses were significantly more likely to have a larvae-infested flower vase than Muslims' houses. Townhouses had relatively few infested containers, while those on rubber plantations had 18.3 times higher odds of having at least one container with larva. No window screens increased the odds of larva infestation in the discarded containers by 4.2 times. With this information and given a reliable piped water supply, the number of water containers can be reduced to minimize the breeding places. Garbage should be properly disposed of. Screens should be installed, if possible. Buddhists should be advised on the proper protection of flower vases.     

Parvovirus B19 antibodies in immunocompromized children in Thailand

Parvovirus B19, a non-enveloped single stranded DNA virus is distributed worldwide. Sero-prevalence in adult populations amounts to approximately 50%. Clinical manifestations vary depending on the Immune status of the infected individuals and may include mild childhood Infection as well as hydrops fetalis due to intrauterine infection. To determine the prevalence of this infection among the immunocompromized individuals in Thailand, we determined, by indirect ELISA, levels of IgM and IgG antibodies to the parvovirus B19 in 106 immunocompromized children. These included 49 children who were on chemotherapy for treatment of malignancies, 18 who were receiving immunosuppressive drugs after organ transplantations, 14 who were under a regimen of corticosteroids and 25 who were positive for antibodies to HIV. The average prevalence of IgG antibodies in 106 children was 16.0%; the prevalence of antibodies was 33.3% in post-transplanted group, 16% in children positive for HIV, 12.2% in the group receiving chemotherapy for malignancies and 7.6% in the group treated with corticosteroids. All children were negative for IgM antibodies to parvovirus B19.     

Elevated serum nitric oxide metabolites in biliary atresia

Biliary atresia (BA) remains one of the most intractable liver diseases in children. The aim of this study was to investigate the possible roles of nitric oxide (NO) in BA. Serum levels of nitrite and nitrate (NO production) were determined using a colorimetric method from 65 post-operative BA patients and 12 healthy children. The patients were categorized into two groups according to their jaundice status, and serum alanine aminotransferase (ALT, a marker for liver injury). Unpaired t tests were used. Data are expressed as mean and SD in terms of μmol/l. Age and gender between BA patients and controls were comparable. Serum NO metabolites of BA patients was higher than the controls (79.77±21.22 vs. 65.75±9.44, P=0.001). Subgroup analysis revealed that there was no difference in serum nitrate/nitrite levels of BA patients without jaundice compared to those with jaundice (78.85±23.23 vs. 80.90±18.76, P=0.70). However, patients with serum ALT≥100 IU/l had higher levels of serum NO metabolites compared to those with serum ALT<100 IU/l. In conclusion, NO production was elevated in BA patients compared to normal controls. Serum NO was associated with serum ALT levels, but not with jaundice status, in BA patients. These suggest that NO plays a role in the pathophysiology of liver injury in post-operative BA.     

Molecular epidemiological study of hepatitis B virus among migrant workers from Cambodia,Laos, and Myanmar to Thailand

Although hepatitis B virus (HBV) infection is endemic in Southeast Asia, molecular epidemiological data on HBV circulating in some countries are limited. The aims of this study were to evaluate the seroprevalence of HBV and its genetic variability among migrant workers from Cambodia, Laos, and Myanmar in Thailand. Sera collected from 1,119 Cambodian, 787 Laotian, and 1,103 Myanmarese workers were tested for HBsAg. HBV DNA was amplified and the pre‐S/S region was sequenced for genotyping and genetic mutation analysis. HBsAg was detected in 282 (9.4%). The prevalence of HBsAg among migrant workers from Cambodia, Laos, and Myanmar was 10.8%, 6.9%, and 9.7%, respectively. Of 224 subjects positive for HBV DNA, 86% were classified as genotype C (99% were sub‐genotype C1) and 11.6% were genotype B (30.8%, 34.6%, and 30.8% were sub‐genotypes B2, B3, and B4, respectively). Various point mutations in the “a” determinant region were detected in approximately 18% of these samples, of which Ile126Ser/Asn was the most frequent variant. Sequencing analysis showed that 19.1% of samples had pre‐S mutations, with pre‐S2 deletion as the most common mutant (7.7%) followed by pre‐S2 start codon mutation (3.8%) and both pre‐S2 deletion and start codon mutation (3.3%). High prevalence of HBV infection (approximately 7–11%) was found among migrant workers from Cambodia, Laos, and Myanmar, which may reflect the current seroprevalence in their respective countries. The data also demonstrated that HBV sub‐genotype C1 was the predominant strain and various mutations of HBV occurring naturally were not uncommon among these populations. J. Med. Virol. 82:1341–1349, 2010. © 2010 Wiley‐Liss, Inc.     

High serum matrix metalloproteinase-3 and liver stiffness in postoperative biliary atresia

Background  

Biliary atresia (BA) is a neonatal liver disorder characterized by chronic inflammation and obliteration of extrahepatic bile ducts. The purpose of the study was to investigate serum matrix metalloproteinase-3 (MMP-3) in postoperative BA patients and the association of MMP-3 with clinical outcome and liver stiffness score.     

Molecular characterization and phylogenetic analysis of H1N1 and H3N2 human influenza A viruses among infants and children in Thailand

The annual influenza outbreaks can cause a high mortality rate among infants and children. In the tropics, influenza shows no clear dependence on seasons. In the present study, we performed molecular and phylogenetic analysis of H1N1 and H3N2 influenza virus isolated from infants and children diagnosed with respiratory tract illness between February 2006 and February 2007. A total of 33 samples (10.92%) were found positive for human influenza virus infection. Characterization of the hemagglutinin gene revealed conserved sequences at the receptor-binding site as well as variations due to amino acid substitutions at the antigenic site, potentially resulting in an N-linked glycosylation site. As for the neuraminidase gene, amino acid substitutions were found in N1 and N2 but not directly at the catalytic or framework sites of this enzyme. Based on the phylogenetic tree, the hemagglutinin 1 (HA1) region and the neuraminidase (NA) gene of both H1N1 and H3N2 isolated subtypes clustered with the current vaccine strain for the Northern Hemisphere 2007-2008. This finding contributes to understanding the evolution of influenza A viruses in humans and is useful for surveillance and vaccine strain selection.