Susanta Kumar Chakraborty

Emergence and present status of Lu-177 in targeted radiotherapy: the Indian scenario

Abstract 177Lu is presently considered to be a potential radionuclide for the development of agents for radionuclide therapy owing to its favorable nuclear decay characteristics [T1/2 = 6.65 d, Eβ(max) = 0.497 MeV, Eγ = 113 KeV (6.4%) and 208 KeV (11%)]. While the long half-life of this promising radioisotope offers distinct logistic advantage, particularly, in countries having limited reactor facilities, the feasibility of its large-scale production with adequate specific activity and excellent radionuclidic purity in medium flux research reactors constitute yet another desirable feature. Extensive studies have been carried out to optimize the production of this isotope, with high specific activity and radionuclidic purity by the (n,γ) route using the highest available flux and the optimum irradiation time. The gradual evolution of clin ical grade 177LuCl3 as a new radiochemical, ready for commercial deployment by Radiopharmaceuticals Division, Bhabha Atomic Research Centre, to nuclear medicine centers all over India was accomplished in 2010 in a stepwise manner with the commencement of the production of high specific activity 177Lu from enriched target in 2001. Research on 177Lu has demonstrated its immense potential in radiotherapeutic applications, a direct outcome of which has resulted in indigenous development of two agents viz. 177Lu-EDTMP and 177Lu-DOTA-TATE presently being evaluated in human patients for palliative care of bone pain due to skeletal metastases and treatment of malignancies of neuroendocrine origin, respectively. Using locally produced 177Lu, the radiolabeling of a plethora of other molecules with potential applicability in radiation synovectomy and targeted therapy of malignant tumors have been successfully demonstrated. A few of these agent such as a novel 177Lu-labeled porphyrin has shown considerable promise in initial studies and is presently evaluated. In the present article, our research efforts toward standardization of production methodology of 177Lu in high specific activity and its utilization in the devel opment of agents for targeted radiotherapy are being reported.

Development of tools for assessing conservation categories of siluroid fishes of fresh water and brackish water wetlands of South West Bengal, India

Twenty-five species of fishes belonging to 18 genera, 7 families under the order siluriformes have been recorded from different freshwater and brackish water wetlands of South West Bengal, India. Fishery potential of 17 commercially important siluroid fishes were noted especially from market surveys as well as from information collected from local fishermen communities. Following the IUCN guidelines, and also through Participatory Rural Appraisal (P.R.A.) methods, an attempt has been made to assess the conservation status of such fishes, many of which are thought to be threatened. Trend analysis, Fish Magnitude Value and Rank based Quotient revealed the threatened status of 17 siluroid fishes.

Conservation categories of siluroid fishes in North-East Sundarbans, India

In stock fishery of North-East Sundarbans, siluroid fishes hold a remarkable position owing to the culture potentiality of many of them. Scales in fishes play significant role in protection and resistance against environmental stresses and the lack of scalation in case of siluroid fishes is supposed to be one of the reasons for their decline in eco-degraded aquatic habitats. 11 species of fishes belonging to 9 genera, 8 families under the order Siluriformes have been recorded from different water bodies of North-East Sundarbans, India. Fish Magnitude Value (FMV) of those catfishes were recorded especially by information harvested from local fishermen community and stakeholders as well as from market survey on fish landing. The extensive damage to the population of catfishes in the area has placed the fishes under threat categories. Following the IUCN guidelines and also through Participatory Rural Appraisal (PRA) methods, an attempt has been made to assess the status of such fishes. Trend analysis, Fish Magnitude Value (FMV) and Rank Based Quotient (RBQ) revealed 1 catfish as Endangered, 5 as Vulnerable and 5 as Near Threatened species. The situation warrants immediate attention of ecologists, administrators, managers and entrepreneurs to propose remedial measures for revival of the fishes. The study also delineates distribution, present status and conservation measures for revival of the fishes in North-East Sundarbans wet-land environment of West Bengal, India.

Biochemical and stress responses of rohu Labeo rohita and mrigal Cirrhinus mrigala in relation to acclimation temperatures.

The biochemical and stress responses of two Indian major carps, rohu Labeo rohita and mrigal Cirrhinus mrigala were studied after acclimating them to four preset temperatures (26, 31, 33 and 36 degrees C) for 30 days. The blood glucose and liver glycogen levels showed an inverse trend in both the species and were significantly different in L. rohita at higher temperatures. The decrease in the liver glycogen level of C. mrigala, however, was not significant. Plasma cortisol levels increased significantly whereas the ascorbic acid content in the brain and kidney of both the species decreased significantly with increasing temperatures. Total lipid content in the liver of both the species decreased significantly with increasing acclimation temperatures. The phospholipid concentration decreased in L. rohita with increasing acclimation temperatures, and in C. mrigala the values decreased up to 33 degrees C and increased at 36 degrees C. In C. mrigala, the cholesterol level decreased up to 33 degrees C and then increased at 36 degrees C, but the absolute value was lower in comparison to L. rohita. The cholesterol levels, however, were not significantly different in L. rohita. Triglycerides and free fatty acids concentrations decreased significantly with increasing acclimation temperatures in both the species. The present study indicates species-specific metabolic responses of L. rohita and C. mrigala to thermal acclimation.

Functional role of microarthropods in nutrient cycling of mangrove-estuarine ecosystem of Midnapore coast of West Bengal, India.

Purpose. The present study is aimed at investigating the diversity and ecology of mangrove litter inhabiting microarthropods with a view to assess their functional role in the nutrient cycling by way of decomposition of mangrove litters. Design/methodology/approach. Samplings were made at monthly intervals for the estimation of ecological parameters, recording fluctuation of population and community structure from the selected study site of Midnapore coast of West Bengal, India. Experimental laboratory studies were also undertaken for assessing the rate of insitu decomposition of selected mangrove plant, Avicennia officinalis (L) and phase wise occurrence of microarthropods in decomposing litter. Findings. A total of 44 species of microarthropods belonging to seven major taxonomic groups viz. Acarina (36.3%), Collembola (27.2%) Coleoptera (10%), Diptera (5.7%), Isopoda (5.1%), Hymenoptera (5%) and other associated litter inhabiting microarthropod fauna (10.6%), displayed distinct seasonal fluctuation with regard to their population density and community structure in relation to fluctuating major physico-chemical parameters. Maximum decomposition was found on twelve months (70%) and that of minimum (34%) was observed on three months. Maximum diversity and density of fauna were recorded during six months to nine months of decomposition. Originality/value. Litter inhabiting soil microarthropods play significant role in the energy flow and nutrient cycling in mangrove ecosystem by breaking leaves for the consumption thereby promote leaching and subsequently enhance biochemical alteration along with associated microbial population.

Evaluation of nutrient status of different organic wastes along with environmental quality in the different phases of vermicomposting by Perionyx excavatus Perrier

Purpose – The aim of this paper is to assess the trend of changes of nutritional status and environmental quality of different decomposing organic wastes in different phases of vermicomposting utilizing an indigenous earthworms species Perionyx excavatus.Design/methodology/approach – Four different organic wastes were selected as basic ingredients for vermicompost production. Dried waste materials (2 kg) of each were mixed with dried cow dung and placed in experimental plastic trays with 60 individuals of selected earthworm species. Samples were collected from each tray at an interval of 15 days. Six trays were used: three were with both wastes, three trays having only wastes were treated as control.Findings – Regression equation has shown the rate of change of nutrients – both in control and experiment vermicomposting units over time – which revealed significant changes of C, N, P and C/N ratio during different phases of vermicomposting.Practical implications – Vermitechnology is now being considered as...

Threatened fishes of the world: Wallago attu (Bloch and Schneider, 1801) (Siluriformes: Siluridae)

The Asian Silurid catfish Wallago attu is an endangered species. Populations are declining due to over-exploitation, pollution and environmental degradation. Law enforcement to ban destructive fishing practices should be enhanced for the conservation of the populations.

Assessment of microbial roles in the bioconversion of paper mill sludge through vermicomposting

PurposeMain thrust of the present study is to determine the role of microbes in changing the proportion and turnover of nutrients such as carbon and nitrogen during vermicomposting of paper mill sludge through the assessment of β-glucosidase and Leucine arylamidase activities.MethodsThe change in the ratio of Total Organic Carbon (TOC) and Total Kjeldahl Nitrogen (TKN) during sludge composting using paper mill sludge, cow dung, straw in the ratio of 5:4:1 have been determined alongside observing β-glucosidase and Leucine arylamidase activities in different phases (0th, 30th and 60th days) of vermicomposting. The present study also assessed the bacterial assemblages in order to predict their role as major producers of these enzymes as estimated by Vitek 2 system.ResultsA declining trend of C/N ratio was observed which exhibited significant negative and positive correlations with the activity of β-glucosidase and Leucine arylamidase respectively. Twenty-four strains were isolated under two genus Bacillus spp. and Lysinibacillus spp. which revealed differential sensitivity towards major carbon and nitrogen turnover mediating enzymes.ConclusionChange in the activities of carbon and nitrogen turnover enzymes due to microbial growth and proliferation are the mediator for the change in C/N ratio.

Ecological Services of Intertidal Benthic Fauna and the Sustenance of Coastal Wetlands Along the Midnapore (East) Coast, West Bengal, India

Human existence is entirely dependent on the products and services of biodiversity for food, medicines, shelter, clothing materials, aesthetics etc. Ecological services on the other hand denote the contribution of nature to a variety of “goods and services” to mankind in respect of economics and ecology. Biodiversity being an important component of the mother earth renders valuable ecological services to all the compartments of the environment including coastal zone which is the interface of the land and sea and represents an eco-potential ecosystem along with its different geo-morphological components like estuaries, mangroves, dunes, deltas, lagoons, intertidal zones, etc. The present article focuses on the functional contribution of benthic biodiversity towards sustenance of a short but geo-morphologically diversified intertidal zones of coastal Midnapore (East) District, West Bengal, India which is in continuation of Sundarbans mangrove estuarine complex of India These benthic fauna, both macrobenthos (brachyuran crabs, molluscs, polycaetes, actiniarians etc.) and meiobenthos(nematodes, foraminifera, copepods, polychaetes etc.) render valuable ecological services by making sediments loaded with living organisms by bioturbation, releasing millions of benthic larvae (meroplankton) to the aquatic system as the food of fishes, converting mangrove leaves into detritus,releasing nutrients, ploughing sediments to maintain textural composition, acting as food for demerseal fishes, bioaccumulating pollutants,serving as bioindicator, and providing aesthetics.

Cyathoshiva amaleshi gen. n. sp. n. (Nematoda: Cyatholaimidae) from the coast of India.

A new genus, Cyathoshiva, of free-living marine nematodes from the subfamily Cyatholaiminae (family Cyatholaimidae, order Chromadorida), is described from the Indian coast. The new genus differs from other known Cyatholaiminae genera in having a unique combination of morphological characters: buccal cavity with well-developed dorsal tooth and two subventral teeth, proximally unpaired gubernaculum and non-cup shaped supplements. The type species Cyathoshiva amaleshi gen. n. sp. n. is characterized by having multispiral amphids with 4.5 turns, punctated cuticle with a weak lateral differentiation, a conical tail, three supplements possessing both tubular and setoid parts, and a gubernaculum with a serrated and dentate distal end.