Production of monoclonal antibody to acaricide dicofol and its derivatives

In Thailand detection of acaricide dicofol residues has been sporadically performed due to the limitation of analytical techniques. Conventional analytical methods for detecting dicofol residues most often use chromatographic-based techniques. Our ultimate aim is to develop an alternative method for rapidly analyzing dicofol residues in vegetables and fruit samples. Here we report the production of monoclonal antibodies specific to dicofol and its derivatives. Hapten-protein carriers were prepared by linking succinic anhydride to dichlorobenzhydrol (DCBH), which was then conjugated to bovine serum albumin (BSA) and oval albumin (OVA). DCBH-BSA conjugate was used as immunogen while DCBH-OVA conjugate was used as capture antigen for competitive inhibition assay. Female BALB/c mice were immunized with DCBH-BSA conjugate subcutaneously, and antibody (Ab) level was determined 2 weeks after the last immunization. Spleen cells producing high titer antibody were isolated and fused with myeloma cells of P3.X6.Ag8.653. After limiting dilutions, antibody produced by one clone had high affinity, which was found to be of IgG1 with κ light chain. Specificity and inhibition concentrations of the monoclonal antibody (MAb) were determined by competitive indirect ELISA with dicofol, and its 50% (IC(50)) was 0.28 μg/mL. Working ranges of the developed immunoassay were from 0.07 to 25 μg/mL. Hence, the prepared MAb will be able to be applied for immunoassay development for detecting dicofol residue in vegetables and fruits far below the maximum residue limit such that 5 g of fruits and berries can be detected below 0.1 mg/kg.     

Cost of standard indoor ultra‐low‐volume space spraying as a method to control adult dengue vectors

Objectives To access the costs of standard indoor ultra‐low‐volume (SID‐ULV) space spraying for controlling dengue vectors in Thailand. Methods Resources related to SID‐ULV space spraying as a method to control dengue vectors between July and December 2009 were identified, measured and valued taking a societal perspective into consideration. Information on costs was collected from direct observations, interviews and bookkeeping records. Uncertainty of unit costs was investigated using a bootstrap technique. Results Costs of SID‐ULV were calculated from 18 new dengue cases that covered 1492 surrounding houses. The average coverage of the SID‐ULV was 64.4%. In the first round of spraying, 53% of target houses were sprayed and 44.6% in the second round, of which 69.2% and 54.7% received entire indoor space spraying. Unit costs per case, per 10 houses and per 100 m² were USD 705 (95% Confidence Interval CI, 539–888), 180 (95% CI, 150–212) and USD 23 (95% CI, 17–30). The majority of SID‐ULV unit cost per case was attributed to productivity loss (83.9%) and recurrent costs (15.2%). The unit cost of the SID‐ULV per case and per house in rural was 2.8 and 1.6 times lower than municipal area. The estimated annual cost of SID‐ULV space spraying from 2005 to 2009 using healthcare perspective ranged from USD 5.3 to 10.3 million. Conclusions The majority of the cost of SID‐ULV space spraying was attributed to productivity loss. Potential productivity loss influences the achievement of high coverage, so well‐planned SID‐ULV space spraying strategies are needed to reduce costs.     

High sex chromosome aneuploidy and diploidy rate of epididymal spermatozoa in obstructive azoospermic men

Purpose: To evaluate the frequencies of sex chromosome aneuploidy and diploidy rate of epididymal spermatozoa from obstructive azoospermic men and its impact on intracytoplasmic sperm injection (ICSI) outcomes. Methods: Epididymal spermatozoa retrieved from 24 obstructive azoospermic men and ejaculated spermatozoa from 24 fertile donors were analyzed using triple color fluorescence in situ hybridization (FISH) techniques, in order to investigate the rates of diploidy and aneuploidy for chromosomes 18, X and Y. Results: Epididymal spermatozoa from obstructive azoospermic men had total sex aneuploidy, disomy 18, and diploidy rates significantly higher than ejaculated spermatozoa from normozoospermic fertile controls (1.44% vs. 0.14%, 0.11% vs. 0.02%, and 0.18% vs. 0.02%, respectively; p < 0.005). There were no statistically significant differences in ICSI outcomes between the patients who had high and low epididymal sperm aneuploidy rate. Conclusions: Epididymal spermatozoa from obstructive azoospermic patients had an elevated sex chromosome aneuploidy and diploidy rate. The increased frequency of chromosomal abnormalities did not have a direct effect on the ICSI outcome.     

Does zinc deficiency play a role in stunting among primary school children in NE Thailand?

Stunting in school-age years may result in a decrease in adult size, and thus reduced work capacity and adverse reproductive outcomes. We have compared the mean intakes of energy, protein and selected growth-limiting nutrients in fifty-eight stunted children and 172 non-stunted controls drawn from 567 children aged 6-13 years attending ten rural schools in NE Thailand. Control children were selected randomly after stratifying children by age in each school. Dietary data were calculated from 24-h recalls using nutrient values from Thai food composition data and chemical analysis. Inter-relationships between stunting and sociodemographic, anthropometric and biochemical variables were also examined. Biochemical variables investigated were serum albumin, zinc, ferritin, transferrin receptor and retinol, and iodine in casual urine samples. Significantly more males than females were stunted (males, n 38, 65.5% v. females, n 20. 34.5%: P=0.025). Stunted males had lower mean intakes of energy, protein, calcium, phosphorus and zinc, and a lower mean (95% CI) serum zinc (9.19 (8.53, 9.84) v. 9.70 (8.53, 9.29) micromol/1) than non-stunted males; no other biochemical differences were noted. Stunted males also had a lower mean arm muscle area (P= 0.015), after adjusting for age, than non-stunted males. In conclusion, the lower dietary intakes of the stunted males compared to their non-stunted counterparts may be associated with anorexia and hypogeusia induced by zinc deficiency. Hence, zinc deficiency may be a factor limiting linear growth, especially among boys in NE Thailand, but more research is needed to establish whether other factors also play a role.     

Nutritional Support with Omega-3 Fatty Acids in Burn Patients: A Systematic Review with Meta-Analysis of Randomized Controlled Trials

Background: In burn patients, the profound effect of nutritional support on improved wound healing and a reduced rate of hospitalization and mortality has been documented. Fish oil as a primary source of omega-3 fatty acids in nutritional support may attenuate the inflammatory response and enhance immune function; however, unclear effects on the improvement of clinical outcomes in burn patients remain. Methods: The systematic literature review was conducted by searching the electronic databases: Cochrane Library, PubMed, ScienceDirect, and Scopus to assess the randomized controlled trials of nutritional support with omega-3 fatty acids compared to control diets in patients that presented with burns from any causes. Results: Seven trials were included in this meta-analysis. We found no significant differences in length of stay (LOS) (p = 0.59), mortality (p = 0.86), ventilation days (p = 0.16), gastrointestinal complications—e.g., constipation and diarrhea (p = 0.73)—or infectious complications—e.g., pneumonia and sepsis (p = 0.22)—between the omega-3-fatty-acid-receiving group and the control/other diets group. Conclusions: We did not find a benefit of omega-3 support in reducing the various complications, mortality and LOS in burn patients. Further studies are necessary to find the effect of nutritional support with omega-3 fatty acids over low-fat diets in this population.     

Low zinc,iron, and calcium intakes of Northeast Thai school children consuming glutinous rice-based diets are not exacerbated by high phytate

Phytate, a salt of phytic acid (myo-inositol 1,2,3,4,5,6-hexakisphosphate), is found in certain plant-based foods. It strongly chelates minerals, forming insoluble complexes in the small intestine that cannot be digested or absorbed. Information on the phytate content of rice-based diets of children in Northeast Thailand is limited. In this study 1-day weighed duplicate diet composites were collected from 40 Northeast Thai children (age 6–13 years) randomly selected from participants (n=567) of an efficacy trial in Ubon Ratchathani province. Diet composites were analyzed for zinc, iron, and calcium by atomic absorption spectrophotometry, and for phytate (as inositol penta-phosphate and hexa-phosphate) by high-performance liquid chromatography; the accuracy and precision were established using a certified reference material for the minerals and an inter-laboratory comparison for phytate. The median (1st, 3rd quartiles) zinc, iron, and calcium contents of the diet composites were 4.3 (3.7, 6.1), 4.3 (3.2, 6.5) and 130 (82, 216) mg/day, respectively. The inositol penta-phosphate and hexa-phosphate levels were so low they were below the detection limit, attributed in part to leaching of water-soluble potassium and magnesium phytate from glutinous rice after soaking overnight before cooking. Clearly, phytate will not compromise mineral absorption from these diets. Instead, low zinc intakes are probably primarily responsible for the low zinc status of these children. In contrast, although intakes of dietary iron appear low, the prevalence of biochemical iron deficiency was also low, suggesting that iron absorption may have been higher than previously assumed. Whether the low calcium intakes compromise optimal bone health in these growing Northeast Thai school children is unknown.