Epidemiology and immunodiagnostics of Strongyloides stercoralis infections among migrant workers in Malaysia

To investigate the status of Strongyloides(S.) stercoralis infections among migrant workers in Malaysia for the first time and identify risk factors. Methods: Four diagnostic methods were employed for the detection of S. stercoralis including microscopy, enzyme-linked immunosorbent assay (ELISA) using a commercial kit, ELISA using the rSs1a antigen and polymerase chain reaction (PCR). Low and semi-skilled workers from five working sectors (i.e. manufacturing, food service, agriculture and plantation, construction and domestic service) were tested on a voluntary basis. Results: The overall seroprevalence of S. stercoralis from 483 workers employing the ELISA commercial kit for IgG was 35.8% (n=173; 95% CI: 31.5%-40.1%) whereas seroprevalence using the rSs1a-ELISA was 13.0% (n=63; 95% CI: 10.0%-16.0%). Cross tabulation between the ELISA commercial kit and rSs1a-ELISA showed that only 6.4% (n=31; 95% CI: 4.2%-8.6%) of the samples were positive in both tests. Microscopic examination of all 388 fecal samples were negative; however subsequent testing by a nested PCR against DNA from the same samples successfully amplified DNA from three male subjects (0.8%; 3/388). Male workers, India and Myanmar nationality, food service occupation and those living in the hostel were statistically significant with seroprevalence (P<0.005). Conclusion: This is the first report on the epidemiology of S. stercoralis infections among the migrant workers in Malaysia. Our results highlight the importance of using appropriate diagnostic tools for detection. The presence of anti-S. stercoralis antibodies in the study population calls for improvements in personal hygiene and sanitation standards among migrant workers in Malaysia through control strategies including health education campaigns and programs aimed at increasing awareness and healthy behaviors.

teratogenic effects of retinoic acid on epithelioreticular cells and hassall's corpuscles in the medulla of the chick thymus

Objective: To examine the effects of prenatal administration of retinoic acid on the proliferation of epithelioreticular cells and Hassall's corpuscles in the medulla of chick thymus

Study Design: Experimental study

Place and Duration of Study: Anatomy Department, College of Physicians and Surgeons Pakistan [CPSP] Regional centre, Islamabad, from February 2009 to February 2010

Materials and Methods: A total of 120, fertilized chicken eggs were divided into an experimental group A, and its control group B. Group A was injected with retinoic acid via yolk sac on day zero of incubation. Group B was sham injected with saline. Subgroup A1 and B1 were incubated till embryonic day 15 and subgroups A2 and B2 were incubated till hatching. The number of epithelioreticular cells and Hassall's corpuscles were counted. Diameter of Hassall's corpuscles was measured. The parameters were compared statistically between the experimental and control groups

Results: The number of epithelioreticular cells was significantly less than the control group at embryonic stage [p=0.009] as well as at hatching [p=0.001]. The number of Hassall's corpuscles was not different between the embryonic groups but was considerably more than the control in the experimental group at hatching [p=0.01]. The diameter of the Hassall's corpuscles belonging to the experimental groups was significantly different than the age matched control groups at the embryonic stage [p=0.004] as well as at hatching [p=0.008]

Conclusion: Prenatal exposure to retinoic acid significantly reduced the number of epithelioreticular cells and increased the size and the number of the Hassall's corpuscles

Third molars and angle fractures

Fractures of the mandibular angle are common and mandibular third molars are frequently implicated in their pathogenesis. The study was done to investigate this cause and effect relationship. The objectives were to measure the relationship between presence and status of mandibular third molar [M3] and mandibular angle fracture. Study design was descriptive. It was carried out in the Department of Oral and Maxillofacial Surgery, Punjab Dental Hospital, attached with de, Montmorency College of Dentistry, Lahore. 87 patients with clinical and radiographic diagnosis of mandibular fracture formed the study group. The predictor variable was the presence or absence of mandibular third molar. The outcome variable was the presence or absence of angle fracture. Hemi mandibles containing a third molar were seen to have a 2.3 times increased risk of having an angle fracture [p = 0.49] than a hemi mandible without a third molar. A significant association between third molar depth and risk of angle fractures was seen [p = 0.001]. The presence and depth of mandibular third molar is associated with an increased risk for mandibular angle fracture

effect of prenatal administration of valproic acid on the survivability and day of hatching of chick embryo

To assess the effects of prenatal administration of valproic acid on the survivability and day of hatching of chick embryo in comparison with age-matched controls. The experimental study was conducted at the Department of Anatomy, Regional Centre of College of Physicians and Surgeons Pakistan, Islamabad, from February 2010 to February 2011. Fertilised chicken eggs were divided into two groups, labelled as experimental group-A and control group-B. Group-A eggs were injected with valproic acid, incubated and hatched. Group-B eggs underwent sham treatment using normal saline. The fully hatched chicks were then evaluated for the day of hatching and survivability, on hatching or on day 22 of incubation whichever was earlier. Outcome was statistically compared with the controls using SPSS 10. The two groups had 30 eggs each. In Group-A 23[76.66%] chicks hatched out, while there were 7[23.33%] dead chicks. In Group-B, 28[93.33%] chicks hatched out and 2[6.66%] were dead. Chicken embryos exposed to valproic acid in ovo showed increased mortality [p<0.001] and delayed hatching [p<0.001]. Prenatal exposure of chick embryos to valproic acid decreased embryo survival and also delayed hatching compared to age-matched controls

Atrial and ventricular septal changes in ethanol vapour exposed chick embryos

To study the effects of ethanol vapour exposure on development of atrial and ventricular septa of chick embryo. The experimental study was conducted at the College of Physicians and Surgeons, Islamabad, from 2006 to 2007. The experimental and control groups were further divided into three subgroups based on the day of sacrifice. The experimental group was exposed to ethanol vapours produced in a specially-designed vapour chamber and then compared with age-matched controls. There were 90 eggs in each of the two groups. The development of inter-ventricular septum completed at day 7 of development in chick embryo. Ethanol vapour exposure produced a small discontinuity at day 10 of development in a chick embryo which may be labelled as ventricular septal defect since ventricular development is completed by day7. Interatrial septum formed till day 7 with small perforations which persisted till hatching. Ethanol vapour exposure may lead to ventricular septal defect

Mobile phone radiations, possible disruptor to early retinal development

This study was conducted with an objective to investigate the effects of mobile phone induced radiations on retinal morphogenesis of chick embryo. Experimental Study. This study was conducted at Anatomy department, Regional Centre, College of Physicians and Surgeons Pakistan, Islamabad from Jan. 2006 to Jan. 2007. Chicken embryos were exposed to mobile phone silent mode ringing by placing a GSM operated phone in the centre of the fertilized eggs developing in the incubator. This phone was ringed upon for 15 minutes twice daily for one experimental subgroup and 25 minutes twice for the other subgroup. The control and experimental groups were sacrificed at the end of 10 post incubation days. The retinae of the embryos were dissected out and statistically compared for the heights of different retinal layer after paraffin processing of sections. For lower dosage [15 minutes of ringing] of mobile phone induced EMFs. Thickness of the rods and cones layer and inner plexiform layer of the treated subgroup was significantly less than the control. On increasing the dosage to 25 minutes, thickness of the pigment epithelial layer of the treated group was significantly more than the control group. All the other layers were more in thickness in this subgroup but this difference was not statistically significant. The results of the study conclude that mobile phone radiations have a dose dependant regulatory effect on the early developmental process of chick embryo retina. EMFs dose Mobile phone induced EMFs disrupt the developmental process of embryonal retinogenesis. This effect is influenced differently at different levels exposure

comparative histological study of the surface epithelium and high endothelial venules in the subepithelial compartments of human nasopharyngeal and palatine tonsils

To compare the thickness and organization of surface epithelium, and high endothelial venules in subepithelial compartments of human nasopharyngeal and palatine tonsils, with reference to functional differences. Comparative cross-sectional. The Anatomy Department of CPSP Regional Centre, Islamabad, from January to December 2005. Thirty samples each of human nasopharyngeal, right palatine and left palatine tonsils were collected by convenience sampling technique. Haematoxylin and eosin stained paraffin sections were examined for surface epithelium. Thickness of stratified squamous and pseudostratified ciliated columnar epithelium was measured, while organization was observed in case of stratified squamous. The high endothelial venules in subepithelial lymphoid compartments were counted. The surface epithelium of nasopharyngeal tonsils [stratified squamous and pseudostratified columnar inclusive] was 63.21 +/- 1.93 micro m, and that of palatine [stratified squamous] was 143.99 +/- 5.94 micro m thick [p<0.001]. The mean count of high endothelial venules in subepithelial compartments of nasopharyngeal was 1.15 +/- 0.06 and that of palatine tonsil was 0.93 +/- 0.08 [p=0.042]. Organization of stratified squamous epithelium was poor in 26 out of 30 nasopharyngeal, and well in all palatine tonsils [p <0.001]. The surface epithelium of nasopharyngeal tonsil being thinner and poorly organized than that of palatine tonsil might act as a less effective barrier between the antigenic stimulus and subepithelial lymphoid compartments. This may contribute towards higher level of immune response by these compartments of the former, which is endorsed by higher number of high endothelial venules as compared to the latter

Histological study of human placenta with emphasis on capillaries and syncytial knots of terminal villi

To study the light microscopic structure of human placenta from different regions. To determine the role of the placenta in nutrition of the human fetus. A descriptive study The study was conducted at MH Rawalpindi from January to June 2002. Ten placentae of normal cases were used in this study. Placentae was cut along the maximum diameters into two halves after trimming the membranes. Three specimens were taken: one from the centre [A], one from the peripheral margins [C] and one from midway between the two [B]. m thick sections Specimens were further processed for paraffin sections. Five were made on rotary microtome. Haematoxylin and eosin [HandE], Periodic acid schift [PAS] and Masson's trichrome stains were used. The morphology of villi was observed, and syncytial knots and capillaries were counted. The placental tissue was arranged as a chorionic plate, a basal plate and between the two the villous stems, their branches in the intervillous space. Mean number of syncytial knots in A, B and C regions were 144 +/- 22.56, 93 +/- 26.70 and 93 +/- 21.52 respectively. The quantitative difference between regions A, B and C was statistically insignificant [P>0.05], Mean number of capillaries in A, B and C regions was 114 +/- 46.04, 89 +/- 27.23 and 92 +/- 36.80 respectively. The quantitative difference between regions A, B and C was statistically insignificant [P>0.05]. In terminal villi, the syncytial knots and capillaries were more in the central [A] region as compared to in the peripheral [C] region. The quantitative difference between syncytial knots and capillaries of central [A] and peripheral [C] region was statistically insignificant

Study of the effects of cimetidine upon rat testis

The effect of parenteral administered high [950 mg/kg] and low [150 mg/kg] dose of cimetidine on germinal epithelium of seminiferous tubules of testis in adult albino rats was studied. Cimetidine in high doses produces reduction in testicular weight and size, increase in tubular count per low power field and decrease in diameter and thickness of germinal epithelium of seminiferous tubules. The testicular changes observed could be due to toxic effect of drug on the body in general and testis in particular or it may have been mediated through hormones

Histological study of extrahepatic part of human biliary tree with emphasis on peribiliary glands

Extrahepatic part of human biliary tree was lined with simple tall columnar epithelium. Supranuclear cytoplasm of the cell was darkly stained. Histochemistry of the epithelium revealed that it was mucus secreting. Below the epithelium there was a thick compact layer of connective tissue. Outside the compact layer there was a loose layer of areolar tissue in which smooth muscle, blood vessels and nerves were found. Glandular acini were present within and outside the compact layer of intrapancreatic bile duct [IPBD] and common bile duct [CBD] whereas these were present only within the compact layer of bile duct of ampulla of Vater [BDAV]. Statistical significance of quantitative difference between glandular acini of BDAV with other regions revealed that the difference was significant [P < 0.01] with IPBD and non significant [P > 0.05] with CBD. Statistical significance of quantitative difference between glandular acini of IPBD with other regions revealed that the difference was significant [P < 0.01 and P < 0.05] with BDAV and CBD respectively. Statistical significance of quantitative difference between glandular acini of CBD with other regions also revealed that difference was significant [P<0.05] with IPBD whereas it was not significant with BDAV [P>0.05]. Intramural and extramural glandular acini were present in IPBD and CBD whereas BDAV contained only intramural glands. The difference between intramural and extramural glandular acini was statistically significant [P < 0.02] in IPBD. The difference between intramural and extramural glandular acini of CBD was also statistically highly significant [P<0.001]. Glandular acini as demonstrated by different stains were 100% mucous type in BDAV and IPBD whereas it was mixed type in CBD. The acini of CBD were serous, mucous and mixed type. The difference between serous and mucous, mucous and mixed glandular acini was statistically highly significant [P<0.001]. The difference between serous and mixed glandular acini was statistically not significant [P>0.05]. Ratio of serous, mucous and mixed glandular acini was 1:22:1 respectively