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In about last three decades, many developing countries have experienced a large decline in maternal mortality rates. Global initiatives leading to better maternal health policies may have contributed to this decline. In this paper, we investigate whether maternal health intervention also improves the fetal survival rate. For this purpose, we consider the Village Midwife Program in Indonesia, which was launched in 1989 as a part of the safe motherhood strategy. Using the Indonesian Family Life Survey (IFLS), we investigate the impact of midwives on fetal survival rate in terms of a change in the likelihood of a live birth being male. Our results show that the provision of a midwife in a community increases the probability of a live birth being male by about 3 percentage points. Greater antenatal care, skilled birth-attendance, and an improvement in nutrition among reproductive-age women—in terms of greater BMI—are the likely pathways. We do not find the results to be driven by pre-treatment trends, and they remain robust to a number of checks.

A field survey through questionnaire was conducted in rice-prawn (Macrobrachium rosenbergii)-fish culture ghers in six villages of Khulna, Satkhira and Bagerhat districts of south-west Bangladesh during March to December, 2008 to assess present culture practices. About 10-25% of the total area of land was converted for building canals and dikes and the remaining area were used for rice cultivation. Boro with prawn and fish appeared to have positive impact on the economic return as well as on the livelihood of the farmers. After harvesting rice, total area were used for prawn and fish culture. Cost benefit analysis revealed that the seed cost of prawn was the highest variable cost. Higher seed cost of prawn and fish can be reduced by ensuring the available supply of seed in proper time. The average Net Return (NR) was BDT 72,395±4,6943 ha-1yr-1 and the Rate of Return (RR) of the rice-prawn-fish farming was 14.64%. Compared with mono crop culture system, the rice-prawn-fish integrated farming in ghers appeared to be economically viable, socially acceptable and environmentally sustainable.

The proximate composition of four commonly found edible aquatic plants (both leaves and stems) from south-western coastal regions of Bangladesh, such as Helencha (Enhydra fluctuants), Malancha (Alternanthera philoxeroides), Shapla (Nymphaea nouchali) and Kochu (Colocasia esculenta) was determined to evaluate their nutritional value in terms of crude protein, lipid and moisture contents. The moisture contents of leaves ranged from 59.41±1.0 % to 67.16±1.0% and that of stems from 70.19±1.0% to 83.03±1.0% (fresh weight). The crude protein contents of leaves ranged from 9.04±0.2 % to 20.58±0.5% and that of stems 6.34±0.4 % to 19.64±0.6% ; the lipid contents of leaves ranged from 1.12±0.2% to 2.96±0.1% and that of stems 1.11±0.3% to 2.02±0.2%; and the ash contents of leaves ranged from13.39±0.5% to 16.13±0.5% and that of stems from 14.29±0.5% to 17.28±0.5% (dry weight). The results revealed that the plants contained essential amount of protein, lipid and moisture which compete favourably well with those of commercially available agricultural vegetables.

Seasonal and gender impacts have not been well considered in fecal exposure assessment, especially in low- and middle-income countries. This study examined the seasonal and gender impacts on fecal exposure trends in children through daily living activities in an urban slum in Bangladesh. We determined Escherichia coli concentrations in seven types of environmental samples (n = 232) and the activity data of children via diary recording, questionnaires, and interview surveys. Daily and monthly exposures were stochastically estimated for drinking, eating, pond bathing, well bathing, and hand-to-mouth contact. Of the five pathways, pond bathing and drinking contributed a large part of the daily and monthly exposure. Significant seasonal differences were observed in daily exposures for bathing, which were higher in the rainy season (2.59 × 102 CFU/day for boys and 6.19 × 10−1 CFU/day for girls) than in the dry season (1.69 × 102; 4.30 × 10−2), because of longer pond bathing time and more contaminated bathing water in the rainy season. In contrast, eating had significantly higher exposure in the dry season (3.71 × 10; 3.22 × 10) than the rainy season (1.50 × 10; 1.24 × 10) due to the higher dish contamination. Significantly higher daily exposure was observed in the bathing for boys than girls, as boys spent longer time for bathing at a heavily contaminated pond. HIGHLIGHTS Seasonal and gender impacts on fecal exposure were studied in a slum in Bangladesh.; Escherichia coli levels of seven types of samples and activity data of children were collected.; Fecal exposure of children through five pathways was modeled by seasons and gender.; Drinking predominantly contributed to the exposure of girls regardless of seasons.; Boys’ preference to pond bathing caused the largest exposure in the rainy season.

Stocking density of fish is species specific and is considered as one of the crucial aspects for optimizing feed and water-quality management in biofloc system. The present study was carried out to determine the optimum stocking density of a prime aquaculture species, climbing perch Anabas testudineus in biofloc system. Fish fingerlings with a mean initial weight of 0.80 ± 0.02 g were reared in biofloc tanks for 13 weeks under three different stocking densities, 300 (T-300), 450 (T-450), and 600 (T-600) fish m−3 in triplicates, and the fish were fed with a commercial diet at 3% of their body weight. At final harvest, significant differences in growth and body composition were observed among the treatments. T-300 and T-450 showed similar growth pattern (p > 0.05), while fish in T-600 registered significantly poor growth (p 0.05), while significant (p

We study the problem of estimating higher-order stochastic volatility [SV ( p ) ] models. Due to the difficulty of evaluating the likelihood function, this remains a challenging problem, even in the relatively simple SV ( 1 ) case. We propose simple moment-based winsorized ARMA-type estimators, which are computationally inexpensive and remarkably accurate. The proposed estimators do not require choosing a sampling algorithm, initial parameter values, or an auxiliary model. We show that a Durbin–Levinson-type updating algorithm can be applied to recursively estimate models of increasing order p . The asymptotic distribution of the estimators is established. Due to their computational simplicity, the proposed estimators allow one to perform finite-sample Monte Carlo tests. Simulation results show that the proposed estimators have lower bias and mean squared error than all alternative estimators (including Bayes-type estimators). The proposed estimators are applied to S&P 500 daily returns (1928–2016). We find that an SV ( 3 ) model is preferable to an SV(1) model.

Tilapia (Oreochromis niloticus) is one of the most promising aquaculture species in Bangladesh, the culture of which is mostly dependent on the supply of hatchery-produced seed. Published information on genetic monitoring and genetic variability of the hatchery-reared tilapia population is rare in Bangladesh. Therefore, intra- and inter-population genetic variations were estimated among the five mono-sex tilapia populations collected from the matchday-kanon, khan, nancy, city, and brac hatcheries located at different districts in Bangladesh. Random amplified polymorphic DNA (RAPD) markers were amplified from tilapia’s muscle DNA of each of the five populations using ten decamer random primers. The primers produced a total of 181 scorable bands of which 64.1% were found to be polymorphic ranged in molecular size from approximately 100bp to 2000bp. The brac population obtained the highest genetic variability (51%) of overall polymorphic loci and the lower index was estimated (55-62%) in that population with the four others in pair-wise similarity comparison. Moreover, a common pattern of distinctive genetic variation was observed in the brac hatchery population when the genetic differentiation (FST), gene flow (Nm) and genetic distance (D) had been analyzed. The distinctiveness was also supported from the unweighted pair group method of arithmetic mean (UPGMA) dendrogram analysis where the five populations aligned into two clusters- the brac alone belonged to one and the rest of the four grouped into another. Our overall findings reveal that a low level of genetic variation exists in the current tilapia populations of Bangladesh except in the brac hatchery population where broodstock is known to be well managed. This low level of genetic variation of the tilapia hatchery population will have a seriously detrimental effect on this species and its overall production if the genetic quality is not maintained.

Multiple spawnings are special reproductive tactics that many fish evolved to obtain different types of direct and/or indirect spawning benefits. This has led to two pertinent questions: (a) what types of benefit does a commercially important fish provide during multiple induced spawnings annually? and (b) is there any trade‐off between traits during these spawnings? To address these questions, the present study was carried out with two separate experiments during two spawning events of an Indian major carp (Catla catla) to assess: (a) male's spawning performances and (b) female's spawning performances. The male's spawning data revealed that they produced significantly higher amount of milt and hatchlings during the first spawning, while they significantly reduced hatchling deformation rate, enhanced offspring survival rate and enlarged offspring body size during the second spawning. The female's spawning information unveiled no significant differences in total egg weight, hatching rate and hatchling deformation rate between the first and second spawning. However, females had significantly higher offspring survival rate during the first spawning and enhanced offspring body size during the second spawning. Interestingly, the analysis of trait associations revealed that males allocated energy with a trade‐off between milt weight and offspring survival rate, whereas females showed a trade‐off between hatching rate and offspring survival rate. Thus, the study provides some important information for carp breeders and associated stakeholders to know which spawning season is preferable for the higher production of eggs, milt and good quality larvae.

Mangrove leaf litter is a potential source of nutrients for shrimp post larvae. To introduce mangrove trees in shrimp farms it is necessary to identify the combination of trees which is most beneficial for shrimp. The present study evaluated the effects of mixed leaf litter of four mangrove species (Avicennia officinalis (Ao), Sonneratia apetala (Sa), S. caseolaris (Sc) and Heritiera fomes (Hf) on shrimp post larvae performance and water and soil quality. Leaf litter with and without supplemental feed was applied to shrimp culture tanks according to a 4 × 2 factorial design and followed by testing a subset of treatments in mesocosm pond conditions. Shrimp post larvae of 15-days old (PL15) with an average weight of 0.01 g were used for both experiments, each with a 4-week duration without water exchange. Under controlled conditions in the tanks, leaf litter and feed resulted in 22 to 32% higher weight gain of PL shrimp than combined weight gain realized when receiving only leaf litter or only feed, indicating synergism. Based on this, the pond experiment was designed with combined application of leaf litter and feed. The pond experiment resulted in higher shrimp weight gain than realized in the tanks. In tanks, the highest average individual weight gain of PL was observed for the leaf litter mixture SaAoHf (0.23 g)followed by SaScHf (0.21 g), ScAoHf (0.21 g) andSaScAoHf (0.20 g). Paralleling the results of the tank experiment, SaAoHf leaf litter also gave the highest average individual weight gain (1.2 g) of PL shrimpin the ponds but other leaf litter treatments followed by SaScAoHf (0.95 g), ScAoHf (0.84 g) and SaScHf (0.69 g) leaf litter. The different mixtures of mangrove leaf litter also resulted in significant differences in biological oxygen demand (BOD5), phytoplankton and zooplankton concentrations in pond water and organic carbon in soil. Both phytoplankton (P < 0.01, Pearson correlation r = 0.910)and zooplankton (P < 0.05, r = 0.535) abundance was positively correlated to shrimp weight gain. The low feed conversion ratio (FCR) in the treatments combining leaf litter and supplemental feed as compared to treatments using only feed indicated extra food benefits for shrimp PL from decomposing leaf litter. Overall, mixed mangrove leaf litter had a positive effect on shrimp performance and this effect was highest for SaAoHf leaf litter.

Quantitative and qualitative analyses of important bacterial content for public health concern (total bacterial count, total coliforms, faecal coliforms, Salmonella and Vibrio cholerae) of cultured fresh water prawn and farm water which has significant role in order to manage sustainable aquaculture were carried out. Microbiological parameters of prawn (Macrobrachium rosenbergii) and farm water were determined by following the ISO standard methods. Total bacterial Count (standard plate count) found in prawn samples ranged from 5.55 to 5.71 log CFU/g while 4.13 to 4.18 log CFU/mL in water sample. On the other hand, total coliforms found in prawn sample ranged between 1.96 to 2.46 log CFU/g whereas in water sample 2.07 to 2.46 log CFU/mL total coliforms were detected. In case of faecal coliforms, the number ranged between 0.96 to 1.42 log CFU/g in prawn sample and 1.59 to 1.81 in water sample. While Vibrio cholerae was absent in both prawns and water sample and Salmonella was detected in two tested ponds for both prawn and water sample.

Shrimp based mangrove-aquaculture (silvo-aquaculture) is practiced in many countries of the world and leaf litter of different mangrove tree species is a potential nutrient source in these systems. The present study evaluated the effects of mangrove leaf litter from four mangrove species (Sonneratia apetala, S. caseolaris, Avicennia officinalis and Heritiera fomes) on the production of juvenile shrimp (Penaeus monodon) with and without supplemental feed. Fifteen-day-old post larvae (PL15) with an average weight of 0.01 g were reared in 1100 L fibre-reinforced polyethylene tanks containing 1000 L of 10 ppt saline water and a water depth of 0.9 m. Leaf litter with or without supplemental feed was applied to the tanks according to a 4 × 2 factorial design. The PLs were stocked at a density of 100 per tank and the experiment was conducted for 4 weeks without any exchange of water. Both mangrove species and feed application affected shrimp performance and water quality parameters except dissolved oxygen (DO), chemical oxygen demand (COD) and zoo-plankton concentration. The average survival rate of juvenile shrimp ranged from 86 to 94% in the treatments with both leaf litter and feed, 75–82% in the treatments with only leaf litter and 88% in the treatment with only feed. However, 100% mortality was observed in the treatment without any leaf litter or supplemental feed. Combined, leaf litter and feed resulted in 21 to 33% higher weight gain of shrimp PL than based on the combined contributions of leaf litter only or feed only, indicating synergism. Among the different mangrove species, S. apetala (23.1%) contributed the highest to total weight gain followed by A. officinalis (21.6%), S. caseolaris (21.6%) and H. fomes (10%). The lower feed conversion ratio (FCR) (0.18–0.27) in the treatments combining leaf litter and supplemental feed as compared to the feed-only treatment (0.41) indicated that leaf litter (directly or by stimulating natural food production) contributed to supplemental feeding. The growth of phytoplankton also appeared to contribute in low FCR as evidenced by a positive correlation (P < 0.001, r = 0.681⁎⁎) between phytoplankton concentration and shrimp weight gain. The synergistic effect between leaf litter and supplemental feed can help the farmer to minimize the shrimp production cost by lowering the feed input and enhancing mangrove three coverage on pond dikes as an inexpensive source of natural food.

Mangroves of tropical and subtropical shores and deltas contribute to ecosystem functioning and human wellbeing in numerous ways but continue to be lost or degraded worldwide at a rapid pace. Overexploitation driven by poverty is often the root cause of mangrove destruction and degradation. The negative feedback cycle between destruction and poverty can only be broken by justly valuing current or introducing new sustainable livelihood options to foster long-lasting local support for mangroves. The large array of non-timber forest products (NTFPs) that mangroves offer have rarely been developed beyond the subsistence level and remain undervalued as &ldquo, products of the poor&rdquo, In light of the global trends towards sustainability and bio-economy, today they represent a major business opportunity for forest communities to produce high value-added end-user products. Even though mangrove NTFPs have been recognized to have high potential toward inclusive development and poverty alleviation and to be highly gender-equal, the development of mangrove NTFPs has continued to attract very little funding or research interest. Several ecological characteristics make commercialization of mangrove NTFPs particularly challenging. Production at economies of scale, including quality standards, as well as marketing and value chain management are all essential in order to develop these products beyond their subsistence role. To be most effective, a systems perspective on NTFP development is needed, whereby product-market development occurs in unison and based on a participative, inclusive and fair development approach. The species/product of choice for value-added product-market development in any specific community or area will depend on several factors. To address many of the typical constraints and maximize the chances of success, we suggest that the use of village or district-level cooperatives may be particularly useful. A better use of the untapped potential of mangroves for local livelihoods may form a most convincing advocate for local protection and restoration of mangrove forests. Therefore, funding agencies, governments and researchers alike are called to invest in mangrove NTFP development as a way to locally incentivize sustainable mangrove protection and restoration.

Mangrove forests are remarkably diverse and productive ecosystems, with distinctive biophysical environments in intertidal coastal regions of the tropics and subtropics. In these regions, shrimp cultivation is identified as a profitable business and one of the main reasons for clearing of mangroves to construct shrimp farms. Against this backdrop and based on the first author's previous PhD research and other relevant scholarly works, in this commentary we discuss the aspects and contexts of the mangrove-based integrated shrimp farming system. Then, we recommend a model of co-management and a set of policy option towards sustainable silvo-aquaculture to protect/restore the mangrove forests and sustain shrimp production in coastal areas of Bangladesh. Mangrovesand shrimp culture are not necessarily incompatible. Many mangrove species have been identified as beneficial for shrimp culture for a number of possible reasons. Most importantly, the nutrients in the leaf litter of several mangrove species have been found to enhance natural food production for shrimp. Besides the nutrient input, the leaf litter also provides surface area for biofilm development, on which different life stages of shrimp can graze. In addition, the combination of mangrove leaf litter and feed has been shown to enhance shrimp productionsynergistically. Additional economic benefits from mangrove-shrimp co-management include the production of timber (e.g. buildings, boats and fuel woods) and non-timber products (e.g. fruits, honey, fibers, firewood, resinsand bark). Thus, mangrove-based aquaculture or silvo-aquaculture system can be considered as a nature-based solution to sustainably revitalize the economy in coastal areas where shrimp has been the economic mainstay. Though there are positive effects, we point out some potential negative impacts of mangrove-based shrimp culture, like the anti-nutrients content in the leaf litter, which might impact shrimp production. In addition, the long term use of mangrove leaf litter might degrade the water quality. Therefore, the co-management policyrecommends a controlled practice of mangroves in shrimp culture to balance conservation of mangrove-based ecology and profitable shrimp production. The approach promotes nature-based solutions and fosters sustain-able pathways for food production, considering socio-economic and environmental dynamics

This study investigated the occurrence of Escherichia coli pathotypes in sanitary wastewater and drinking water in a Bangladeshi urban slum and the potential associations between these sources. We examined 621 E. coli isolates from sanitary wastewater and stored drinking water by multiplex PCR and dual-index sequencing, classifying them into eight pathotypes based on 14 virulence genes and additionally evaluating the possession of the human-specific E. coli genetic biomarker H8. The proportions of pathogenic E. coli were significantly different (P

The release of nutrients and anti-nutrients from mangrove leaf litter plays an important role in the biogeochemical cycling in aquatic environments and directly or indirectly affects water quality and food availability to shrimp. In this study, we assessed nutrient and anti-nutrient loss during decomposition of leaf litter at a concentration of 1 g/L for four mangrove species (Avicennia officinalis, Heritiera fomes, Sonneratia apetala, Sonneratia caseolaris) to monitor water quality and to estimate how leaf litter influences shrimp post larvae (PL) growth and survival. There were significant differences (P < 0.05) between the studied species in terms of mass loss of the leaf litter during the investigation period. There were also significant differences (P < 0.05) between the studied species in terms of loss of nutrients and anti-nutrients in the shrimp PL rearing tank during the four-week experimental period. Decomposing mangrove leaves stimulated availability of natural food for shrimp PLs. There was a strong positive correlation between mass loss and PL production. At the concentrations of leaf litter used, the anti-nutritional factors did not affect the PLs. PL survival with mangrove leaf litter was 75–82%, whereas all the PL died without any leaf litter. PL weight gain ranged from 0.83–3.33 mg/d where S. apetala leaf litter resulted in the highest PL growth rate, followed by A. officinalis, S. caseolaris and H. fomes, in that order (P < 0.05). Overall, mangrove leaf litter had a positive effect on shrimp performance in terms of growth and survival and this effect was highest for S. apetala leaf litter.

Although a stenohaline freshwater fish, the stinging catfish Heteropneustes fossilis, is also available in the freshwater fringes of the coastal areas of Bangladesh, the tolerance of this species to variable environmental salinity has not been thoroughly investigated. Based on median lethal salinity (MLS-50 96 h), three sublethal salinity levels (3 ppt, 6 ppt and 9 ppt) and a control (0 ppt), each with three replications were selected to observe the effects of mildly brackish conditions on the fish for a period of 90-day exposure. Better growth and survival were found up to 6 ppt compared with control. Salinity more than 6 ppt appeared unsuitable for H. fossilis fingerling due to increased mortality and reduced growth. To determine biochemical alterations, a few important physiological parameters were observed after 90 days of exposure. Glycogen level of liver and muscle in the fish reared at 9 ppt salinity decreased significantly (P

Background: Aluminium phosphide is used to control rodents and pests in grain storage facilities. It produces phosphine gas, which is a mitochondrial poison. Unfortunately, there is no known antidote for aluminium phosphide intoxication and the mortality rate is very high. This type of poisoning (known as Kerry or Rice tablet poisoning) is common in Comilla region in Bangladesh. Methods: The study was an observational study and was conducted in the Department of Medicine and in Emergency Room of Comilla Medical College Hospital, Comilla, between February and August, 2013. Twenty five cases of Kerry tab. Poisoning were studied about their causes, clinical features, treatment and outcome. Results: Most of the patients (92%) were female and age range was 15-45 yrs. Familial disharmony was the main reason of their suicidal attempts. This poisoning was common in Chandina, Sadar, Debidar, Burichong, B.para, Muradnagar and Daudkandi upazillas of Comilla District. Vomiting and features of shock were the major clinical menifestations. Routine ECG was not done to these patients. Most of the patients (80%) were referred to higher centres in Dhaka after the primary management. Only 20% patients were survived due to early stomach wash and supporting medical management. One patient who survived also mentioned of taking date expired Kerry tablet. Conclusion: Strict implementation of nationwide pesticide regulation, including restricting the availability of poison, being aware of its toxicity and providing improved medical management and improved intensive care facilities can further reduce the mortality due to AlP toxicity as there is no antidote available presently. DOI: http://dx.doi.org/10.3329/jdmc.v23i1.22685 J Dhaka Medical College, Vol. 23, No.1, April, 2014, Page 3-6

Introduction: Arrhythmias are not uncommon after Coronary Artery Bypass Graft (CABG) surgery. There is increasing evidence that Magnesium, the important intracellular cation plays a crucial role in preventing and terminating cardiac arrhythmias. Objectives: The aim of this study was to establish the role of peroperative use of intravenous Magnesium in reducing the incidence of per and postoperative arrhythmias in CABG surgery. Materials and methods: A total sixty (Group-I 30 and Group-II 30) patients of both sexes and different ages undergoing conventional CABG surgery under general anesthesia in CMH Dhaka from January 2009 to December 2011 were selected randomly. After induction, Group-I received 2 gm of Magnesium in 100 ml normal saline intravenously over a period of 30 minutes and Group-II received no Magnesium. Parameters recorded per and postoperatively were- aortic cross clamp time, Cardio Pulmonary Bypass (CPB) time, total surgery time, Heart Rate (HR), Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP) and blood sample were collected on arrival to Cardiac Intensive Care Unit (CICU) and after 6, 12, and 24 hours. Results were expressed as mean ± SD (Standard Deviation) or in frequencies (percentage) as applicable. The results were analyzed by Student’s ‘t’ test. Results: Magnesium levels were significantly (p

Introduction: Delayed reverse from the effect of neuromuscular blockade and from the effect of anaesthesia is a concern among anaesthesiologists. Objectives: Objectives of the study were to compare reversal pattern of neuromuscular blockade by clinical and instrumental methods and to elicit reliable clinical parameters. Methods: This prospective study was carried out in CMH, Dhaka among 50 adult patients and reversal pattern of neuromuscular blockade was evaluated by clinical and instrumental methods among pancuronium group(Group-I) and rocuronium group(Group-II). All data were collected in data collection sheet and were compiled and analyzed by Student’s‘t’ test. Results: Clinical assessment was carried out by bedside test for muscular function & instrumental assessment was carried out by nerve stimulator and Train of Four (TOF). In pancuronium group (Gp-I) clinically patient was reversed on average (6.19 ± 2.04 min) (mean±SD, n=25) earlier than instrumental method of which tidal volume was found less reliable. But in rocuronium group (Gp-II) instrumentally patient was reversed average (12.56 ± 3.41 min) (mean±SD, n=25) earlier than clinical method of assessing reversal, here also tidal volume was found less reliable among clinical variables. Conclusion: The study revealed that tidal volume is the less reliable among the clinical variables. In Group-I clinical reversal criteria for neuromuscular blockade were fulfilled earlier than that of instrumental method but in Group-II instrumental criteria were fulfilled earlier than clinical method. We should combine 2 or 3 clinical criteria for adequate reversal from neuromuscular blockade. DOI: http://dx.doi.org/10.3329/jafmc.v9i1.18725 Journal of Armed Forces Medical College Bangladesh Vol.9(1) 2013: 43-48

The purpose of the present study was to examine the suitability of cryopreservation solutions for the embryos of olive barb Puntius sarana, a small-sized, freshwater, endangered fish. The specific objective was to examine the toxicity of various cryoprotectants (CPA) and to test the effectiveness of solutions of cryoprotectant mixtures (CS) to different developmental stages of olive barb embryos. Embryos at three developmental stages (gastrula, somites, and tail elongation stages) were exposed to 10, 15, 20, 25, and 30 % solutions of five cryoprotectants, propylene glycol (PG), methanol (MeOH), dimethyl sulfoxide (DMSO), dimethylformamide (DFA), and ethylene glycol (EG). Further, thirteen cryoprotectant mixture solutions comprising these five cryoprotectants were also used at different concentrations to test the toxicity to the embryos. Hatching rates decreased with increasing cryoprotectant concentrations and toxicity to olive barb embryos varied in the order of PG

Specific investigation on the time (h) required for catfish, Clarias batrachus , embryos to reach various early developmental stages were carried out under different experimental conditions. Five hundred fertilized eggs were incubated in tray (28oC–30.5oC) with continuous water flow and aeration (T1), with only continuous water flow (T2) or aeration (T3) and without continuous water flow and aeration (T4). Fertilized embryos hatched successfully in all treatments except for T4. Time requirements for 2-cell, 4-cell, 8-cell, morula, germinal ring, yolk-plug, twisting movement, prehatching and hatching were comparable for all treatments. However, developmental speed was ceased from yolk-plug stage for T4. Time requirements for two-cell, four-cell, eight-cell, morula, germinal ring, yolk-plug, twisting movement, and hatching were 0.43, 0.48, 0.53, 3.52, 6.07, 8.50, 15.04, 20.08, and 21.40 h, respectively for T1; 0.44, 0.47, 0.51, 3.49, 6.10, 8.51, 15.13, 20.19, and 21.56 h, respectively for T2; 0.50, 0.53, 0.59, 3.52, 6.13, 8.53, 15.11, 20.18, and 22.13 h, respectively for T3. Fertilized eggs of C. batrachus incubated in tray with only aeration (T3) is sufficient for successful hatching and could be cost-effective for hatchery operation. DOI: http://dx.doi.org/10.3126/eco.v18i0.9395 Ecoprint : An International Journal of Ecology Vol. 18, 2011 Page: Uploaded date : 12/20/2013

A microarray comprising 3,514 cDNAs was constructed from a medaka EST library to elucidate the transcriptional responses associated with temperature shift from 25 to 15 degrees C in a medaka cell line. Microarray analysis revealed that the mRNA levels of 313 clones were significantly different in at least one combination of different incubation periods up to 7 days at a given incubation temperature or between 25 and 15 degrees C at a given incubation period (P < 0.05). These genes are known to be associated with various biological processes including morphogenesis, cell proliferation and response to stress. A number of genes encoding proteins which localize in extracellular areas were apparently up-regulated at 15 degrees C, whereas those localizing in intracellular areas were down-regulated at this temperature. In addition, while a number of genes represented long-term expression changes, only a few responded to short-term inductions. A typical example was CYR61, a multifunctional matricellular signaling modulator, the mRNA levels of which increased after temperature shift from 25 to 15 degrees C in 3 h, and then decreased rapidly to near the original level within 12 h. Another series of analyses by quantitative reverse transcription-PCR revealed that the mRNA levels of CYR61 at 5 degrees C were significantly higher even at 24 h after temperature shift compared to those of the cells successively maintained at 25 degrees C. These analyses suggest that remodeling and reorganizing of extracellular structure of cells are important to offset the low temperature effect and CYR61 is considered to be a novel gene associated with temperature response in poikilotherms.

Summary The crude extracts obtained from the heads of Northern shrimps, Pandalus borealis, (adapted to cold), showed considerable collagenolytic activities. When tested for beef tenderization, resulted in an overdegradation of meat proteins, which was detected organoleptically. Subsequently, four fractions with proteolytic activity were partially purified from the crude extracts by hydroxyapatite followed by MonoQ or Superdex 200 column chromatography. Warner-Bratzler shear force values of steaks treated with three protease fractions (Q, S2, S3) at 10 °C were significantly lower (P

We purified a cathepsin L-like proteinase to homogeneity from the hepatopancreas of northern shrimp Pandalus borealis by several chromatographic procedures. The purified proteinase showed the highest specificity for leucine residue at P2, a specificity pattern similar to cathepsins S and K whereas proline and arginine residues were not suitable as P2 substrates. However, unlike these proteinases, it accepted valine almost equally to the phenylalanine residue at P2. The shrimp cathepsin was strongly inhibited by E-64, leupeptin and antipain, while benzyloxycarbonyl-Phe-Tyr(t-Bu)-CHN2, a specific inhibitor of cathepsin L, remained largely ineffective. Next, we determined the primary structure of the shrimp enzyme by molecular cloning and investigated the residues constituting the S2 subsite, which is possibly involved in its unusual substrate specificity. The deduced amino acid sequence of the shrimp proteinase shared the highest identity of 65% with a cathepsin L-like proteinase from lobster, but its identity to the well-characterized mammalian cathepsins S, L, and K fell within narrower ranges of 52-55%. However, the shrimp proteinase differed from these cathepsins in some key residues including, for example, the unique occurrence of cysteine and glutamine residues at the structurally important S2 subsite. Interestingly, transcripts of this proteinase were exclusively detected in the shrimp gut coinciding with its broad pH activity and stability profiles, which is also unusual as a cysteine proteinase. These results suggest that the shrimp enzyme is homologous to mammalian cathepsins S, L, and K, but is distinct from each of these proteinases in both enzymatic and structural properties.

We cloned a cDNA encoding cathepsin B from the hepatopancreas of northern shrimp Pandalus borealis (NsCtB). Nucleotide sequence of the isolated clone encoded a preproenzyme of 328 amino acids, comprising a 15-residue putative signal peptide, a 60-residue propeptide and the 253-residue mature enzyme. The mature NsCtB was 53% identical to human cathepsin B and conserved all the structural features characteristic of cysteine protease. The presence of an occluding loop in the mature region, a unique feature of cathepsin B, suggested the shrimp protein to be cathepsin B. Northern blot analysis revealed expression of NsCtB transcripts exclusively in the hepatopancreas tissues, suggesting a possible digestive role of this enzyme. An interesting feature of NsCtB was its remarkably high negative charge in comparison with other cysteine proteases, which was predicted to effectively locate and guide the positively charged residues of a substrate into the binding cleft. We also observed a repertoire of cysteine protease activities in the acidic milieu of shrimp hepatopancreas using synthetic substrates specific to various cathepsins. The activity profile revealed cathepsin B as the single most dominant enzyme with a specific activity comparable to that attributable to combined activities of other cathepsins. This activity could be blocked by E-64, a cysteine protease inhibitor, but not by Z-Phe–Tyr (t-Bu)–CHN2, a specific inhibitor of cathepsin L.

Three gelatinolytic proteases (A1, A2, and B) were purified using a synthetic substrate, DNP-Pro-Gln-Gly-Ile-Ala-Gly-Gln-d-Arg, from the hepatopancreas of Northern shrimp (Pandalus eous) by several chromatographic steps involving hydroxyapatite column chromatography, gel filtration on Superdex75, and ion-exchange chromatography on a MonoQ column. Collagenolytic proteases A2 and B, but not protease A1, were demonstrated to digest native porcine type I collagen at 25 °C and pH 7.5. Further characterizations of these two collagenolytic proteases showed that the pH optimum of enzyme A2 against DNP-peptide was found to be 11, whereas that of enzyme B was 8.5. The optimum temperature ranged between 40 and 45 °C for both enzymes, although enzyme B appeared to be thermally more stable than enzyme A2 at pH 7.5. Both enzymes were strongly inhibited by PMSF and antipain, which suggests that they belong to collagenolytic serine proteases. Keywords: Collagenolytic protease; Northern shrimp; Pandalus eous; hepatopancreas

Cathepsin L (EC 3.4.22.15) from aquatic animals are quite stable and active at neutral or alkaline pH values while their mammalian equivalents work at an acidic environment of the lysosomes. To understand the molecular properties at the gene level we employed a PCR-based strategy using degenerate oligonucleotide primers to isolate cathepsin L-like genes from anchovy Engraulis japonicus. As a result, we obtained two closely related genes encoding cathepsins (aCat1 and aCat2) similar to both cathepsins L and S from other organisms. The predicted precursor protein of 324 amino acid residues for genes differed in six residues and contained conserved residues characteristic of cathepsin L-like cysteine proteases. Phylogenetic analyses failed to produce any precise relationships of aCat1 and aCat2 with other cysteine proteases. However, with a bootstrap value less than 50, these two fish cathepsins formed a separate group to that bearing cathepsins L and S of various organisms. Interestingly, unlike mammalian cathepsin L transcripts of aCat1 and aCat2 were almost exclusively detected in the stomach suggesting that the fish homologues are non-lysosomal secretory enzymes present in the extracellular acidic environment of the stomach and that marine teleosts developed digestive cysteine proteases as a result of evolutionary pressure in response to varying dietary conditions.

Complementary DNA clones encoding two isoforms of trypsinogen were isolated from the pyloric ceca of anchovy by rapid amplification of cDNA ends (RACE). Nucleotide sequences of isolated clones encoded, in addition to characteristic signal and activation peptides, two isoforms of trypsin containing 220 and 221 amino acid residues. Both enzymes contained the catalytic triad of a serine protease, together with the residues determining substrate specificity. The anchovy trypsins showed a high amino acid identity of about 80% to those of other fish species. Southern blot analysis with a probe cross-reactive to both isoforms showed a complex genomic pattern. Northern blot analysis with the same probe revealed the highest expression of meassenger RNA in the pyloric ceca. Structural parameters possibly involved in higher catalytic properties of fish trypsin were examined by three-dimensional modeling, which included deletion in the autolysis loop, lack of Tyr-151 at the entrance of the S1 pocket, and distribution of charged residues.

A cDNA clone encoding a cysteine proteinase of the papain superfamily has been isolated from the hepatopancreas of northern shrimp Pandalus borealis (NsCys). NsCys shares the highest identity of 64% with a cathepsin L-like cysteine proteinase from lobster, and its identity to the well-characterized mammalian cathepsins S, L, and K falls within a narrow range of 54-59%. However, it differs from each of these cathepsins in certain key residues including, for example, the unique occurrence of tryptophan and cysteine residues at the structurally important S2 subsite. Consequently, NsCys produced in Pichia pastoris appears to be distinct in various physicokinetic properties. The recombinant enzyme is active and stable over a wide range of pH values, and its substrate specificity is unusual, as demonstrated by its poor affinity for phenylalanine residues. Instead, it shows the highest specificity for proline residues, a property similar to cathepsin K. Unlike cathepsin K, however, NsCys cleaves valine residues more efficiently than leucine. Similar results were obtained with the natural peptide substrate glucagon. The shrimp proteinase is further distinguished by its potent collagenolytic activity, resulting in a cleavage pattern reminiscent of bacterial collagenase. To distinguish such unique structural and enzymatic properties, we propose the trivial name "crustapain" for the shrimp proteinase, indicating that it is a papain-like cysteine proteinase from a crustacean species.

Two isoforms of anchovy trypsin (aT-I and aT-II) were purified from the visceral extracts by (NH4)2SO4 fractionation followed by affinity chromatography, gel filtration, and ion-exchange chromatography. The homogeneity of the purified preparation was evidenced by both native- and SDS-PAGE, and further by gelatin zymography. Identities of aT-I and aT-II as trypsins were established by N-terminal amino acid sequencing, which matched exactly to the corresponding stretches of their respective amino acid sequences obtained by molecular cloning [Ahsan et al. (2000), Marine Biotechnol., in press]. Both isoforms were completely inhibited by serine protease inhibitors as well as by specific trypsin inhibitors. The purified anchovy trypsins showed considerably higher catalytic efficiencies (kcat/Km) than bovine trypsin as measured toward benzoyl-arginine p-nitroanilide (BAPA) and benzoyl-arginine ethyl ester (BAEE) at 25 degrees C; in particular, aT-II was 35 times more efficient than its mammalian counterpart against BAPA. This was due mainly to a dramatic decrease of Km values for anchovy trypsins, which are indicative of an evolutionary response toward increased substrate binding at suboptimal temperatures in the marine environment.

The antisera were raised against pepsin-solubilized abalone collagen and its corresponding gelatin. The reactivity against abalone collagen was higher with the anti-collagen than anti-gelatin antiserum. The two antisera recognized all type I collagens from various vertebrates, whereas these had no reactivity against vertebrate type III and type V collagens. Furthermore, both antisera reacted with only alpha 2(I) chains from chicken, rat, and calf. The strong reactivity was observed against the two antisera in the case of invertebrate and protochordate collagens, especially for turban shell collagen. The seasonal changes of collagen mRNA levels were examined in relation to those of collagen content. Haliotis discus collagens (Hdcols) 1 alpha and 2 alpha coding for abalone collagen pro alpha-chains showed quite similar patterns. The highest mRNA levels in adductor and foot muscles for the two collagens were observed in December and January, in good agreement with the increase of collagen content. The mRNA levels decreased in July and August when collagen content decreased. These results indicate that collagen transcription levels are closely related to collagen contents.

Characterized by tidal flats, natural levees and the unique Sundarbans mangroveforest, the coastal zone of Bangladesh is regarded as one of the most productiveecosystems of the world due to regular flush of nutrient rich silts and supply of organic matters from the mangroves. Over the last few decades, however, changes in land use pattern including clearing of mangroves for settlement and agriculture, construction of embankments along the coast to boost rice production and conversion of saline waterlogged agricultural lands to shrimp farming have redefined the coastal landscape and damaged the ecosystem of the coast and the Sundarbans. The tidal forest provides a wide range of ecosystem services (ES) to millions of coastal people, yet unsustainable extraction of resources and traditional economic development continue further jeopardizing the ES potential of mangroves. Lack of knowledge on the value of mangroves ES are largely responsible for such unsustainable practices. True valuation of mangroves ES is a daunting task because all the services cannot be quantified in tangible monetary terms; consequently, efforts in this regard are lacking. Hence, identification of ES and understanding their interplay are crucial to apprehend theactual value of the Sundarbans and its biosphere-supporting contribution to thedynamic delta. This is also necessary to understand how the mangroves ES arecontributing to the wellbeing of the coastal community of Bangladesh whose lives and livelihoods are directly dependent on a healthy ecosystem.