Surface-associated fucoxanthin mediates settlement of bacterial epiphytes on the rockweed Fucus vesiculosus

The chemical defence against microfouling in the brown seaweed Fucus vesiculosus was investigated and an inhibitor of bacterial settlement was isolated by bioassay-guided fractionation of non-polar surface extracts. UV-vis and mass spectrometry were used to identify the compound as the carotenoid fucoxanthin. The metabolite was tested at the natural concentration (in a surface volume based assay) against the settlement of four bacterial strains isolated from F. vesiculosus and 11 strains isolated from co-occurring algae and marine sediment. Surface concentrations between 1.4 and 6 μg cm(-2) resulted in 50% inhibition of four of these isolates, which were studied in more detail using a surface area-based assay, while a fifth isolate proved to be less sensitive. The presence of fucoxanthin on the surface of F. vesiculosus was demonstrated with two different surface extraction methods. Fucoxanthin was detected at concentrations between 0.7 and 9 μg cm(-2) on the algal surface. Fucoxanthin was still present at the algal surface after removal of associated diatoms through mechanical cleaning and germanium dioxide treatment and was thus mainly produced by F. vesiculosus rather than by diatoms. Thus, the photosynthetic pigment fucoxanthin appears to be ecologically relevant as a surface-associated antimicrobial agent, acting against the settlement of bacteria on the surface of the macroalga F. vesiculosus.

Awareness about organ donation among school girls

Prevalence of organ failure is high through out the world. Organ transplantation, the definitive treatment option of organ failure keeps very low due to scarcity of organ. Most of the people are not aware about organ donation. Adolescent girls will be the mother of future nation and they can motivate family members for organ donation. This study was carried out to see attitudes towards organ donation and determine the negative factors of organ donation prevailing among school girls. One hundred sixty eight girls from class VIII to class X of a higher secondary school were participated. A structured questionnaire was filled up by the girls. The data were processed from questionnaire and analyzed. Among study population, most of them (64%) had no idea about on going organ donation and transplantation. The positive attitude of the girls towards organ donation was low when they are live (16%) and their attitudes also kept low even after their death (14%). The girls who did not agree to donate organ were further asked to mention the reasons. The reasons of negative attitude were religious belief, fear of illness and social and familial reservation. The result of this study suggests that among girls, awareness and attitudes about organ donation is poor. There were several reasons identified for low consent rates. Multidisciplinary actions should be taken to improve the awareness of the people about organ donation and motivate them for donation.

Seropositivity of Helicobacter Pylori among the fish handlers

This case control study was done to study the seropositivity of helicobacter pylori among the fish handlers and to find out rapid urease test (RUT) & haematoxillin and eosin staining report correlation of seropositive cases. It was performed among fish handlers in the period of July 2005 to June 2006. Blood samples were collected from fish handlers (Group I) and some non-fish handler control subjects (Group II) to perform Anti-H. Pylori IgG test by ELISA method. Samples were collected from both the sea water area (Paikgacha, Khulna) and fresh water area (Derai, Sunamgonj and Dhaka). Seropositive cases having complaints and treatment history of peptic ulcer diseases were motivated for endoscopic examination to collect biopsy from upper GIT and rapid urease test (RUT) hematoxillin & eosin (H & E) staining were performed. A total of 235 respondents were included in this study, among them 163 were fish handlers (80 sea water and 83 fresh water) and 72 were non fish handler control (25 sea water, 22 fresh water from Sunamgonj, 25 fresh water from Dhaka city). Serum anti- H. pylori test was positive in 126(77.30%) cases in fish handler group (a) and 27(37.5%) cases in the control group (b). Seropositive cases were observed more among the higher age group (>40 years) than in lower age group (<40 years) which was 86% and 67% respectively. Endoscopic examination was done among the seropositive cases having positive PUD features. Total seropositive cases were 153 and among them 81 have positive PUD features, among them 48 cases were selected for endoscopic examination. Among the fish handlers out of 34 cases, 31(91.17%) were RUT positive and out of 14 non-fish handlers 6(42.85%) were RUT positive. Among the fish handlers, 28(82.35%) of the 34-biopsy specimens were H & E positive and among the non-fish handlers, out of 14 samples, 5(35.71%) were H & E positive. Fish handlers have more association of H. Pylori infection than non fish handlers and higher age group persons are more prone to H. Pylori infection. A significant number of seropositive persons have association with positive RUT and H & E staining report.

Development of random amplified polymorphic DNA markers for tropical tasar silkworm Antheraea mylitta

Antheraea mylitta (Drury) is a tropical tasar-silk producing insect. Its populations occupying different ecological and geographical regions show a certain degree of phenotypic variability, for which they are known as "eco-races." The eco-races are exploited for tasar silk production, and they are classified on the basis of their geographical distribution and morphology, which is often misleading when their systematic position is considered. To understand the genetic variability among the different eco-races, we used the random amplified polymorphic DNA (RAPD) method. Eighty random decamer primers were taken for RAPD amplifications. In total, 415 reproducible bands were used to generate a distance matrix, and for the subsequent clustering with unweighted pair-group method with arithmetic average. The number of polymorphic bands detected by each primer ranged from 5 to 24, with a mean value of 14.1 per primer. Percentage polymorphism was 81.9, and genetic distance values ranged from a minimum of 0.0108 between Modal and Nalia eco-races to a maximum of 0.0244 between Modal and Andhra local. The RAPD profiles obtained using A14, BC07, and C17 primers substantially differentiate all 10 commercially important eco-races, and the phylogenetic tree obtained from the data closely follows their geographical separations.

Atypical cutaneous leishmaniasis in two patients receiving low-dose methotrexate

Cutaneous leishmaniasis is a protozoan disease that has high morbidity. There have been increasing reports of leishmaniasis in patients with an underlying immunosuppressed state. We present two cases of cutaneous leishmaniasis caused by Old World species in patients on methotrexate therapy. We postulate that the T-cell-mediated response to leishmaniasis infection could be modulated by methotrexate and may render an immunosuppressed individual more susceptible to developing clinical disease.

Stem cells to repair the broken heart: much ado about nothing?

The long promised benefits of using stem cells for myocardial repair are still awaited.

Interspecific variation in heavy metal body concentrations in biota of Sunderban mangrove wetland, northeast India

The coastal environment of West Bengal, recognized as the most diversified and productive ecosystem among all the maritime states of India, faces organic pollution from domestic sewage and urban and industrial effluents leading serious impacts on biota. The present paper aims at providing information on concentration level of heavy metals among the tissues of benthic polychaetes, bivalve molluscs and finfishes collected from Sundarban mangrove wetland, northeast coast of India. An overall common trend in bioaccumulation was revealed with the following decreasing order: Zn>Mn>Cu>Cr>Se>Hg with few exceptions. Both species dependent variability and temporal variations were pronounced. A high degree of organ specificity was evident in the bivalves where gill and mantle exhibited higher metal accumulation due to ion exchange property of the mucous layer covering these organs. Variability between closely related species is a reflection of different uptake rates, physiology and impact of environmental factors. The results of this analysis suggest that mollusks can play a significant role in trace metal trophic transfer studies, especially as their representatives are intertidally and subtidally ubiquitous.

Evaluation of the concentration of HCH, DDT, HCB, PCB and PAH in the sediments along the lower stretch of Hugli estuary, West Bengal, northeast India

Detailed analyses of persistent organic pollutants (POPs) such as hexachlorocyclohexane (HCH) isomers (HCHs), dichlorodiphenyltrichloro ethane (DDT) and its metabolites (DDTs), hexachlorobenzene (HCB) and congeners of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in surface sediments from the coastal estuarine environment of West Bengal, northeast India allowed the evaluation of the contamination status, distribution and possible pollution sources. HCH, DDT, HCB, PCB and PAH were identified compounds in all the samples, whereas the concentrations of chlorinated pesticides (trans-eptachlorepoxide, dieldrin, endrin, metaoxychlor and mirex) were below the detection limits and were not of great concern. The pesticides did demonstrate markedly different distributions reflecting different agricultural and domestic usage in the region. The range of concentrations of HCH, HCB, DDT and PCBs in the sediments were 0.11-0.40, <0.05-0.98, 0.18-1.93 and 0.18-2.33 ng/g dry wt, respectively. Overall elevated levels of HCB, DDT and PCB were recorded at Babughat, a very closely located site of the metropolitan megacity Calcutta. Fluoranthene (flu) and pyrene (py), the dominant 4-ring PAHs, also showed an abrupt elevated concentrations at Babughat with values of 214 and 144 ng/g dry wt, respectively. Among the isomers and metabolites of HCH, DDT and PCB, alpha-HCH, pp'-DDT and PCB (101), PCB (118), PCB(153) and PCB (138) were found to be dominant. High ratios of metabolites of DDT to SigmaDDTs reveal recent use of DDT in this coastal environment. Fluoranthene, pyrene, 1,2-benzo(a)anthracene and chrysene formed the dominant congeners out of 19 identified PAHs. The sources of contamination are closely related to human activities such as domestic and industrial discharge, automobile exhausts, street runoff, slum sewage, agricultural chemicals and soil erosion due to deforestation as well as atmospheric transport. This study is compared to other coastal and estuarine environments in India and abroad. The baseline data can be used for regular ecological monitoring, considering the industrial and agricultural growth around this important estuarine ecosystem.