Gender Determination Using Morphological Analysis of Palatal Rugae Patterns – A Retrospective Study.

Background: Palatal rugae are unique for an individual and remain unchanged during individual's lifetime. Application of palatal rugae analysis as a method in gender identification needs to be confirmed with more scientific studies. The objectives of the present study were to assess the distribution of the palatal rugae patterns in Kerala population and compare the distribution of these parameters between males and females. Materials & Methods: A retrospective cross-sectional study was conducted by evaluating the casts of 100 dentate individuals, between the age of 18 and 30 years. The rugae were divided into two halves and patterns were then assessed as per Thomas and Kotze classification. Independent sample t-test was used to assess the significant difference of each type of palatal rugae between males and females. Results: Wavy rugae (mean – 5.6 ± 0.7) was predominant among males whereas curved (mean – 4.6 ± 0.6) and circular rugae (mean – 0.9 ± 0.3) were more in females, and were found to be statistically significant (p<0.05). The mean number of secondary rugae in females (1.5 ± 0.5) was greater than that of males (1.3 ± 0.4), and was found to be statistically significant (p<0.05). The diverging type was commonly found in females compared to males. Conclusion: Our findings showed statistically significant differences in the shapes and patterns of rugae between males and females among Kerala population. Thus, morphological analysis of palatal rugae can be considered as an additional aid in forensic odontology for gender differentiation.

Larvicidal & ovicidal efficacy of Pithecellobium dulce (Roxb.) Benth. (Fabaceae) against Anopheles stephensi Liston & Aedes aegypti Linn. (Diptera: Culicidae).

Background & objectives: In view of the recently increased interest in developing plant origin insecticides as an alternative to chemical insecticide, this study was undertaken to assess the larvicidal and ovicidal potential of the crude hexane, benzene, chloroform, ethyl acetate and methanol solvent extracts from the medicinal plant Pithecellobium dulce against the mosquito vectors, Anopheles stephensi and Aedes aegypti (Diptera: Culicidae). Methods: Larvicidal activity of P. dulce plant extracts was studied in the range of 60 to 450 mg/l against early third instar larvae of An. stephensi and Ae. aegypti in the laboratory. The larval mortality was observed after 24 h of exposure. The ovicidal activity was determined against An. stephensi and Ae. aegypti to various concentrations ranging from 100 to 750 mg/l under the laboratory conditions. Mean per cent hatchability of the eggs were observed after 48 h post treatment. Results: All leaf and seed extracts showed moderate larvicidal and ovicidal effects; however, the highest larval mortality was found in methanol extract of leaf of P. dulce against the larvae of An. stephensi and Ae. aegypti with the LC50 and LC90 values 145.43, 155.78 mg/l and 251.23, 279.73 mg/l, respectively. The per cent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. Zero hatchability was observed at 400 mg/l for leaf methanol extract and 625 mg/l for seed methanol extract of P. dulce against An. stephensi and Ae. aegypti, respectively. Compared to leaf extracts, seed extracts have low potency against the two mosquitoes. Interpretation & conclusions: The present results suggest that the leaf and seed extracts of P. dulce have the potential to be used as an ideal eco-friendly approach for the control of mosquitoes.

Recent advances in the diagnosis of leishmaniasis.

Leishmaniasis is a parasitic disease caused by a haemoflagellate Leishmania. There are more than 21 species causing human infection. The infection is transmitted to humans through the bites of female sandflies belonging to 30 species. The disease manifests mainly in 3 forms: the visceral, the cutaneous and the mucocutaneous leishmaniasis. The diagnosis of visceral form is conventionally made by the demonstration of amastigotes of the parasite in the aspirated fluid from the bone marrow, the spleen, and rarely from the lymph nodes, or the liver. The parasite demonstration and isolation rates are rather poor from cutaneous and mucocutaneous lesions due to low parasite load and high rate of culture contamination. Recently several recombinant proteins have been developed to accomplish accurate diagnosis. Recombinant kinesin protein of 39 kDa called rK 39 is the most promising of these molecules. The antigen used in various test formats has been proved highly sensitive and specific for visceral leishmaniasis. It is useful in the diagnosis of HIV-Leishmania co-infection and as a prognostic marker. Molecular techniques targeting various genes of the parasite have also been reported, the PCR being the most common molecular technique successfully used for diagnosis and for differentiation of species.

Nested polymerase chain reaction in the diagnosis of congenital cytomegalovirus infection.

OBJECTIVE: Human cytomegalovirus infection is highly prevalent in Indian population. It is the commonest congenitally acquired infection causing various anomalies. The diagnosis of infection in neonates is difficult as IgM may not be detected in all cases. The polymerase chain reaction is reported as alternative and better option in these patients. However, there is lack of data to substantiate this preference in a resource poor country like India. METHODS: Blood samples from 930 neonates/fetuses were first tested for specific anti-CMV IgM antibodies using mu-capture enzyme linked immunosorbent assay, Mac-ELISA. Nested PCR was first standardised on clinically and therapeutically confirmed cases of CMV disease. In the second phase blood samples randomly from 20 babies suspected of CMV infection were collected for serology and PCR and both tests were run independently. Twenty healthy controls were also included. IgM ELISA and PCR were performed on these samples and results of these 20 samples were compared to evaluate the sensitivity and specificity of each method. RESULTS: Out of 930 serum samples of suspected congenital CMV infection 188 (20.2%) were found positive for CMV specific IgM antibodies. While comparing the results of 40 paired samples, PCR was found to be highly specific (100%) but less sensitive than Mac-ELISA (95%) with negative predictive value of 100% and positive predictive value of 95%. Thus in congenital CMV infection Mac-ELISA was less costly, less cumbersome and more user friendly. CONCLUSION: The Mac-ELISA seem to have parallel sensitivity and specificity as PCR for diagnosing congenital CMV infection.

Successful replacement of fetal calf serum with human urine for in vitro culture of Leishmania donovani.

Leishmania donovani causes visceral leishmaniasis claiming several thousand lives every year in Indian sub-continent. The etiological agent is grown in cell free media supplemented with fetal calf serum (FCS). Urine from human beings and other mammalian species has also been reported to stimulate growth of Leishmania species No study has been carried out Leishmania donovani. Therefore, we studied the feasibility of culturing Leishmania donovani promastigotes in M199 medium supplemented with 10% human urine and compared the phenotypic and genotypic characters under supplementation with urine vis-a-vis FCS. The growth curve showed no significant difference in the promastigote counts in urine vs. FCS supplementation. The best growth was observed in cultures supplemented with the post-menopausal urine. No difference in antigenic bands and RFLP pattern was seen indicating that no alteration occurred in strain specific characters of the parasites cultured with human urine.

Biochemical lesions of platelets stored as concentrates in PVC bags.

Acid-base status of platelet suspension during storage is a measure of the gas permeability of the bag material. To assess the efficacy of the bags available in our market to store platelets, we compared biochemical lesions of platelets stored in an Indian polyvinyl chloride (PVC) triple bag against a Japanese PVC bag standardized for 5 days platelet storage. Platelet concentrates prepared in both control and test PVC bags were stored for 72 h. Two ml samples were drawn 1 h after preparation, and then at 24 h intervals, for analysis. Our data show that the mean pH value in the test bags was maintained above 6.5. However, the CO2 tension was high and O2 tension was low. We also analyzed malondialdehyde (MDA) formation which is a measure of arachidonic acid metabolism, and seemed to be unaffected in stored platelets. Lactate dehydrogenase (LDH) was not released into the plasma excessively and hence significant platelet lysis was absent during storage. Hypotonic shock response (HSR) of platelets stored in both test and control bags was comparable, indicating the possibility of satisfactory post-transfusion recovery.

Morphological & ultrastructural changes of platelet concentrates stored in PVC bags.

To assess the effect of storage bags on platelets, we studied the morphological and ultrastructural changes of samples drawn from platelet concentrates (PC) prepared and stored in triple, poly vinyl chloride (PVC) bags, manufactured in India. Using the scanning electron microscopy, we demonstrate formation of long pseudopods, and interaction through these to form aggregates. When platelets were stored at 23 +/- 2 degrees C, morphological changes were severe compared to the deleterious effects when kept at 22 +/- 0.5 degrees C. Ultrastructural analysis also showed that maintenance of discoid shape and prevention of granule secretion could be improved by storing the platelets at 22 +/- 0.5 degrees C. Significant degree of platelet fragmentation took place when the storage temperature was high. The morphology score done for platelets stored at both 22 +/- 0.5 degrees C and 23 +/- 2 degrees C showed that preservation of discoid shape was better with the former.