Expression and characterization of glutathione peroxidase of the liver fluke,Fasciola gigantica

Parasitology Research - Glutathione peroxidase (GPx) is a key member of the family of antioxidant enzymes in trematode parasites including Fasciola spp. Because of its abundance and central role as...     

Chromosome 10 and 17 deletions and p53 gene mutations in Thai patients with astrocytomas

The tumor suppressor gene locus is known to be partly responsible for the tumorigenesis of sporadic gliomas, but the genetic events that drive the neoplastic process of this tumor remain largely unknown. We correlated the results of loss of heterozygosity (LOH) analysis on chromosomes 10 and 17 and a point mutation analysis of a tumor suppressor gene, p53, in 21 patients with astrocytomas at different stages. LOH was determined in tumor and leukocyte DNAs of primary human central nervous system tumors. The incidence rate of brain tumors corresponded to every p53-coding exon for single-strand conformation polymorphisms (SSCP) and the mutations were confirmed by sequencing. p53 mutations were found in 2 of 10 glioblastomas (20%) and in 1 of 8 low-grade astrocytomas (12.5%). Similarly, LOH on chromosome 10 was also found in 2 of 10 glioblastomas (20%) and 1 of 8 low-grade astocytomas (12.5%). Neither of the p53 mutations nor LOH on chromosome 10 was observed together in the tumor types analyzed. Interestingly, the p53 mutations were found in 29% of patients with LOH on chromosome 17. The fact that p53 mutation and LOH on chromosome 17 were found together only in glioblastomas, suggested that these genetic changes may accumulate during astrocytoma progression.     

Outcomes of group-based treatment program with parental involvement for the management of childhood and adolescent obesity

Objective

An uncontrolled study was conducted to evaluate the effects of a group-based program on weight control, metabolic profiles, and obesity-related complications in obese youth.

Methods

The program consisted of an initial in-patient session and five group sessions, one, two, three, six, and nine months into the study, providing participants and their parents with information about the consequences of obesity and lifestyle modifications. The severity of obesity and obesity-related complications were evaluated at baseline and 12 months after the intervention. The participants’ and their parents’ perceptions of the program were assessed.

Results

Of the obese youth recruited (n = 126), 115 completed the study. Their percentage weight for height and percentage body fat decreased significantly (both p < 0.001), and their insulin resistance, lipid profiles, and transaminases levels improved (all p < 0.01). The prevalence of prediabetes, dyslipidemia, and elevated transaminases decreased significantly (all p < 0.05). The participants and their parents perceived the program as valuable.

Conclusion

A group-based program is effective in managing childhood obesity, improving metabolic profiles, and alleviating certain obesity-related complications.

Practice implications

A group-based program that provides education and raises the awareness of obese children and their parents about the consequences of obesity is an effective model for treating childhood obesity.     

Trend of malaria incidence in highly endemic provinces along the Thai borders, 1991-2001

The intercountry border areas of Thailand have high malaria receptivity and vulnerability that present numerous problems in the control of malaria transmission. This study focused on the 30 provinces of Thailand situated next to neighboring countries, which can be divided into 4 groups: the Thai-Myanmar border (10 provinces), the Thai-Cambodia border (6 provinces), the Thai-Lao border (10 provinces) and the Thai-Malaysia border (4 provinces). The purpose of the present study was to describe the pattern and trend of malaria incidence in the highly endemic provinces along the Thai borders for the 11 years from 1991 to 2001. Analysis of trends showed the distribution of malaria parasites to have shifted from a preponderance of Plasmodium falciparum to Plasmodium vivax along the western border with Myanmar, the northern border with Lao PDR and along the eastern border with Cambodia whereas the southern border with Malaysia the pattern changed from a preponderance of P. vivax to P. falciparum, since 1997. There was a significant difference in annual parasite incidence between borders and non-border districts, especially along the Thai-Myanmar and Thai-Cambodia borders. It is thus evident that all border districts should pay more attention to control of malaria transmission and the activities of the malaria surveillance system, and that monitoring and evaluation of the Thai Malaria Control Program needs to be performed consistently, including some areas where a few malaria cases were found as well as in malaria free areas.     

Prenatal exposure of mice to the human liver carcinogen aflatoxin B1 reveals a critical window of susceptibility to genetic change

It has become axiomatic that critical windows of susceptibility to genotoxins exist and that genetic damage in utero may be a trigger for later life cancers. Data supporting this critical window hypothesis are remarkably few. This study provides a quantitative bridge between DNA damage by the liver carcinogen aflatoxin B₁ (AFB₁) during prenatal development and the risk of later life genetic disease. AFB₁ was given to pregnant C57BL/6J mice, carrying F₁ gestation day 14 (GD14) embryos of the B6C3F1 genotype. Ultra‐high performance liquid chromatography and mass spectrometry (UPLC‐MS) using aflatoxin‐¹⁵N₅‐guanine adduct standards afforded measurement of the AFB₁‐N⁷‐Gua and AFB₁‐FAPY adducts 6‐hr post dosing in liver DNA of mothers and embryos. A parallel cohort gave birth and the livers of the F₁ were analyzed for mutations in the gpt gene at 3 and 10 weeks of age. The data revealed mutational spectra dominated by G:C to T:A mutations in both the mother and offspring that are characteristic of AFB₁ and distinct from background. It was shown that adducts in GD14 embryos were 20‐fold more potent inducers of mutagenesis than adducts in parallel‐dosed adults. This sensitivity enhancement correlated with Ki67 staining of the liver, reflecting the proliferative potential of the tissue. Taken together, these data provide insight into the relative genetic risks of prenatal and adult exposures to AFB₁. Early life exposure, especially during the embryonic period, is strikingly more mutagenic than treatment later in life. Moreover the data provide a baseline against which risk prevention strategies can be evaluated.     

Length of tooth survival in older adults with complex medical, functional and dental backgrounds

BackgroundTooth loss can be considered a failure of current oral health care strategies. Knowing how soon this failure will occur can help clinicians enhance preventive strategies for preventing tooth loss and minimizing its impact. The authors conducted a study to detail tooth survival patterns in an older cohort.MethodsThe authors conducted a retrospective longitudinal study of 491 participants aged 43 to 102 years. They treated the participants' dental conditions before they entered the study. They also collected participants' sociodemographic, medical, functional, cognitive and dental data when they first arrived at the clinic. The authors used Fisher exact tests, χ² tests and analysis of variance to examine the association between baseline characteristics and tooth survival. They generated Kaplan-Meier estimates and used Cox proportional hazards regression models to detail tooth survival and associated risk factors.ResultsThe authors found that tooth survival patterns differed among participants who had different numbers of carious teeth or retained roots (carious or broken teeth that were missing most of their coronal structures) when they first arrived at the clinic (P N/A .001) and between participants who wore removable prostheses and those who did not (P = .02). Participants' tooth loss at different times differed by sex, number of medications being taken and number of carious teeth or retained roots. The authors found that after they adjusted for other factors, tooth survival was associated with the number of carious teeth or retained roots (P = .01), as well as the interaction between the number of carious teeth or retained roots and use of prostheses (P = .02).ConclusionsCaries and the use of removable prostheses synergistically compromised tooth survival in older patients. Patients who wore prostheses and had multiple active carious teeth or retained roots at arrival had the highest risk of losing teeth soon after their existing conditions were treated.Clinical ImplicationsThese findings highlight the need for preventing tooth loss in older adults who wear removable prostheses and have poor oral health. Knowing the groups at the highest risk of experiencing tooth loss soon after dental treatment is received can help dentists better target and design preventive strategies.     

H63D mutation of the hemochromatosis gene and serum ferritin levels in Thai thalassemia carriers

We determined the prevalence of the H63D and the IVS5#1G-A HFE mutations in 370 (169 males and 201 females) Thai thalassemia carriers and 201 normal subjects. While no IVS5#1G-A mutation was found, the H63D heterozygosity was identified in 5.5% (11/201) of normal subjects and 7.3% (27/370) of thalassemia carriers. Within the thalassemic group, the medians (ranges) of serum ferritin were 217.5 ng/ml (20.1-424.3) and 169.8 ng/ml (3.9-3,536.0) in male subjects and 30.4 ng/ml (11.9-130.7) and 49.3 ng/ml (0.6-931.0) in female subjects with (HD) and without (HH) H63D mutation, respectively. The proportions of subjects with elevated ferritin were found to be 37.5% (6/16) for HD and 14.0% (18/129) for HH in male and 0% (0/11) for HD and 3.0% (5/164) for HH in female subjects, respectively. Statistical analysis of all the data revealed no significant difference. Among 14 Hb E/beta-thalassemia patients, no difference in hematological data as well as serum ferritin levels was observed between those with (HD) and without (HH) H63D mutation. Therefore, the H63D heterozygosity has no significant effect on the serum ferritin level and screening for this HFE mutation in thalassemic patients is not recommended.     

Effects of andrographolide on sexual functions,vascular reactivity and serum testosterone level in rodents

In this study, effects of andrographolide from Andrographis paniculata on sexual functions, vascular reactivity and serum testosterone level in experimental animals were observed. The suspension of andrographolide in 5% DMSO was administered orally at the dose of 50 mg/kg to male ICR mice. The female mice involved in mating were made receptive by hormonal treatment. The mating behaviors, mounting latency and mounting frequency, were determined and compared with the standard reference drug sildenafil citrate. Administration of andrographolide significantly decreased the mounting latency at 120 and 180 min and increased mounting frequency at 180 min after treatment. In endothelium-intact rat aortic strips, norepineprine-induced contraction was reduced by preincubation with andrographolide. Administration of 50 mg/kg andrographolide orally to male mice once daily for 2, 4, 6 or 8 weeks had no significant effects on sperm morphology and motility. Interestingly, at week 4, serum testosterone level in mice treated with andrographolide was significantly increased when compared to the control. Thus, the effects of andrographolide on vascular response to norepinephrine and testosterone level observed in this study might be contributed to the sexual enhancing properties observed.