The trade in human liver lobes: bioviolence against organ sellers in Bangladesh

The rapid growth in organ transplantation has created an illicit trade in human organs. The kidney trade has flourished in the last few decades, but in the last few years this has been coupled with an emerging liver trade. This article examines the liver trade sourced from poor sellers in Bangladesh. Through ethnographic fieldwork, I investigate how a landless farmer and a village housewife both sell their liver lobes on the black market, and how the recipients undergo liver transplants in Bangladesh and India. I reveal that liver selling, like kidney selling, is primarily driven by the sellers’ debt. What is surprising, though, in this anthropological analysis is that microcredit, a Nobel Prize-winning economic operation, has negatively contributed to organ selling in Bangladesh. I discover that the liver trade leads to tragic outcomes for both sellers and recipients: the sellers could not repay their loans by selling a liver lobe, while one of the recipients died just over a month after the surgery. I therefore argue that liver trade is advancing through a series of disturbing ironies, resulting in bioviolence, exploitation, and suffering for the vulnerable victims.     

Phytoplankton primary production in a mesotrophic pond in sub-tropical Bangladesh

Annual gross primary productivity in mesotrophic Shahidullah Hall pond (Dhaka, Bangladesh) was 1383.35 g C m⁻² y⁻¹ (arithmetic mean). Daily primary productivity (between 1.6 and 6.8 g C m⁻² d⁻¹ was correlated with chlorophylla, day length and dissolved silica. Chlorophylla related significantly withk, incident light, SRP, alkalinity and conductivity. A negative correlation existed between biomass and rainfall. Productivity, biomass, conductivity, alkalinity, and SRP increased after mid-winter.k, I _k andZ _eu varied according seasonally.P _max related directly with temperature. Seasonal variation of ∝ ^B was 0.0049–0.0258 mg C (mg chla mmol PAR)⁻¹ m⁻². Q₁₀ was 2.12, community respiration 1334.99 g C m⁻² y⁻¹, and the underwater light climate 186.43μE m⁻² s⁻¹.     

Fermentation of corn fibre sugars by an engineered xylose utilizing Saccharomyces yeast strain

The ability of a recombinant Saccharomyces yeast strain to ferment the sugars glucose, xylose, arabinose and galactose which are the predominant monosaccharides found in corn fibre hydrolysates has been examined. Saccharomyces strain 1400 (pLNH32) was genetically engineered to ferment xylose by expressing genes encoding a xylose reductase, a xylitol dehydrogenase and a xylulose kinase. The recombinant efficiently fermented xylose alone or in the presence of glucose. Xylose-grown cultures had very little difference in xylitol accumulation, with only 4 to 5g/l accumulating, in aerobic, micro-aerated and anaerobic conditions. Highest production of ethanol with all sugars was achieved under anaerobic conditions. From a mixture of glucose (80g/l) and xylose (40g/l), this strain produced 52g/l ethanol, equivalent to 85% of theoretical yield, in less than 24h. Using a mixture of glucose (31g/l), xylose (15.2g/l), arabinose (10.5g/l) and galactose (2g/l), all of the sugars except arabinose were consumed in 24h with an accumulation of 22g ethanol/l, a 90% yield (excluding the arabinose in the calculation since it is not fermented). Approximately 98% theoretical yield, or 21g ethanol/l, was achieved using an enzymatic hydrolysate of ammonia fibre exploded corn fibre containing an estimated 47.0g mixed sugars/l. In all mixed sugar fermentations, less than 25% arabinose was consumed and converted into arabitol.     

Production of cellulases and saccharification of lignocellulosics by A. Micromonospora sp.

A locally isolated strain of Micromonospora sp. when grown on different natural cellulosic substrates gave the highest activity of carboxymethylcellulase (34 U/ml) and Avicelase (0.9 U/ml) on rice straw. Sugar cane bagasse was also a good substrate for growth and cellulase production. With commercial cellulosic substrates, highest carboxymethylcellulase (90 U/ml) and Avicelase (2.8 U/ml) activities were when the organism grew on xylan. Saccharification of sugar cane bagasse and rice straw by enzyme preparations of the organism grown on the respective substrates released 5.6 and 5.8 mg reducing sugar/ml. With all enzyme preparations, bagasse was more easily saccharified than rice straw.The authors are with the Atomic Energy Research Establishment, GPO Box 3787, Dhaka 1000, Bangladesh; N.A. Chowdhury, M. Moniruzzaman, and N. Choudhury in the Institute of Food and Radiation Biology, and N. Nahar in the Institute of Nuclear Science and Technology.     

An Overview on the Toxicological Properties of Ionic Liquids toward Microorganisms

Ionic liquids (ILs), a class of materials with unique physicochemical properties, have been used extensively in the fields of chemical engineering, biotechnology, material sciences, pharmaceutics, and many others. Because ILs are very polar by nature, they can migrate into the environment with the possibility of inclusion in the food chain and bioaccumulation in living organisms. However, the chemical natures of ILs are not quintessentially biocompatible. Therefore, the practical uses of ILs must be preceded by suitable toxicological assessments. Among different methods, the use of microorganisms to evaluate IL toxicity provides many advantages including short generation time, rapid growth, and environmental and industrial relevance. This article reviews the recent research progress on the toxicological properties of ILs toward microorganisms and highlights the computational prediction of various toxicity models.     

Cylindrospermopsis raciborskii Virus and host: genomic characterization and ecological relevance

Cylindrospermopsis (Raphidiopsis) raciborskii is an invasive, filamentous, nitrogen-fixing cyanobacterium that forms frequent blooms in freshwater habitats. While viruses play key roles in regulating the abundance, production and diversity of their hosts in aquatic ecosystems, the role(s) of viruses in the ecology of C. raciborskii is almost unexplored. Progress in this field has been hindered by the absence of a characterized virus–host system in C. raciborskii. To bridge this gap, we sequenced the genome of CrV-01T, a previously isolated cyanosiphovirus, and its host, C. raciborskii strain Cr2010. Analyses suggest that CrV-01T represents a distinct clade of siphoviruses infecting, and perhaps lysogenizing, filamentous cyanobacteria. Its genome contains unique features that include an intact CRISPR array and a 12 kb inverted duplication. Evidence suggests CrV-01T recently gained the ability to infect Cr2010 and recently lost the ability to form lysogens. The cyanobacterial host contains a CRISPR-Cas system with CRISPR spacers matching protospacers within the inverted duplication of the CrV-01T genome. Examination of metagenomes demonstrates that viruses with high genetic identity to CrV-01T, but lacking the inverted duplication, are present in C. raciborskii blooms in Australia. The unique genomic features of the CrV/Cr2010 system offers opportunities to investigate in more detail virus–host interactions in an ecologically important bloom-forming cyanobacterium.     

Recent Advances of Using Ionic Liquids for Biopolymer Extraction and Processing

The evolution of petroleum‐derived polymers is one of the crowning accomplishments of the past century. Although the significant economic gains from this industrial model of resource utilization are achieved, the environmental impacts are fatal. One of the principles of sustainable development is to replace such polymers with potential alternatives derived from renewable materials. Biopolymers derived from natural resources afford a new, versatile, environmentally benign feedstock that could exhibit closed‐loop life cycles as part of a future material's industrial ecology. However, the solubility and processability of biopolymer materials provoke a serious bottleneck owing to their dense networks of inter ‐ and intramolecular bondings and structural heterogeneity. Recently, ionic liquids (ILs) have emerged as promising green solvents and acquired augmented appreciation for their peerless power of biopolymer processing. Among the fourteen principle of green chemistry, the two key elements encourage the exploitation of renewable raw materials by using environmentally benign solvents that cover in dissolution of biopolymers using ILs. This mini review represents a brief overview of the comprehensive ILs assisted extraction and processing of various biopolymeric materials for value‐added applications.     

Impact of metal accumulation pattern on the annual rhythmicity of antioxidants and their interrelationship to maintain the oxidative balance in mollusc

A chronological relationship between the annual profiles of oxidative stress markers, the key regulator of stress physiology has been sought in a terrestrial mollusc (Nerita articulata) under natural photothermal conditions. The hemolymph samples were collected at two different times in each month (from January to December) and the same was repeated for two consecutive years throughout an annual cycle. The fluctuations in the concentrations of certain heavy and trace metals (zinc, copper, cadmium, mercury, lead, and nickel) in both soil and hemolymph of Nerita are also estimated accordingly. Therefore, the present study aims to explore the rhythmic responses of oxidative stress marker to assess the impact of different trace and heavy metals on selected mollusc species. We tries to develop a realistic conceptual idea to analyze and predict the effect of changing environmental pollution on the possible shift in the rhythmicity of aforesaid antioxidants in terrestrial mollusc and their adaptive responses to thrive in such environment. Our results indicates that the amplitude of circannual rhythms of all the selected stress markers varied accordingly but the pattern of annual fluctuation is noted to be similar, and correlated with the metal accumulation. Therefore current information might help to frame the adaptive strategies for invertebrate species under similar toxic circumstances.     

Effects of process errors on the production of ethanol by Escherichia coli KO11

Escherichia coli KO11 was previously constructed for the production of ethanol from both hexose and pentose sugars in hemicellulose hydrolysates by inserting the Zymomonas mobilis genes encoding pyruvate decarboxylase (pdc) and alcohol dehydrogenase (adhB). This biocatalyst appears relatively resistant to potential process errors during fermentation. Antibiotics were not required to maintain the maximum catabolic activity of KO11 even after deliberate contamination with up to 10% soil. Fermentations exposed to extremes of temperature (2 h at 5°C or 50°C) or pH (2 h at pH 3 or pH 10) recovered after re-adjustment to optimal fermentation conditions (35°C, pH6) although longer times were required for completion in most cases. Ethanol yields were not altered by exposure to extremes in temperature but were reduced by exposure to extremes in pH. Re-inoculation with 5% (by volume) from control fermentors reduced this delay after exposure to pH extremes. Received 24 July 1997/ Accepted in revised form 16 April 1998