Involvement of NHERF1 in apical membrane localization of MRP4 in polarized kidney cells

Multidrug resistance protein 4 (MRP4/ABCC4), a member of the ATP-binding cassette protein superfamily, confers resistance to nucleoside and nucleotide analogs as well as camptothecin derivatives. MRP4 also mediates the efflux of certain cyclic nucleotides, eicosanoids, conjugated steroids, and uric acid. Depending on the cell type, MRP4 may localize to either apical or basolateral membranes in polarized cells. The adaptor protein NHERF1 has previously been implicated in MRP4 internalization in non-polarized cells. We have now found that NHERF1 levels are very low in polarized MDCKI cells which express MRP4 on basolateral membranes relative to polarized LLC-PK1 cells which express MRP4 on apical membranes. Furthermore, ectopic expression of FLAG-tagged NHERF1 in MDCKI cells and in MDCKI cells stably expressing eGFP-tagged MRP4 causes endogenous MRP4 and eGFP-MRP4, respectively, to traffic to the apical membranes. These data establish NHERF1 as a major determinant of MRP4 trafficking to apical membranes of mammalian kidney cells.     

Isolation and identification of a potent allelopathic substance in Bangladesh rice

Aqueous methanol extracts of Bangladesh rice (Oryza sativa L. cv. BR17) inhibited the growth of roots and shoots of cress (Lepidium sativum), lettuce (Lactuca sativa), alfalfa (Medicago sativa), timothy (Phleum pratense), Digitaria sanguinalis, Echinochloa crus-galli and Echinochloa colonum. Increasing the extract concentration increased the inhibition, suggesting that the BR17 may have growth inhibitory substances and possess allelopathic potential. The aqueous methanol extract of the BR17 was purified and a main inhibitory substance was isolated and determined by spectral data as 2,9-dihydroxy-4-megastigmen-3-one. This substance inhibited root and shoot growth of cress and E. crus-galli seedlings at concentrations greater than 0.03 and 3 μM, respectively. The concentrations required for 50% growth inhibition on cress roots and shoots were 0.22 and 0.47 μM, respectively, and on E. crus-galli roots and shoots were 36 and 133 μM, respectively. These results suggest that 2,9-dihydroxy-4-megastigmen-3-one may contribute to the growth inhibitory effect of BR17 and may play an important role in the allelopathy of BR17. Thus, Bangladesh rice BR17 may be potentially useful for weed management in a field setting. An erratum to this article can be found at     

Otolith microstructure of Japanese sea bass larvae and juveniles: interpretation and utility for ageing

This paper interprets and discusses the usefulness of otolith microstructure for ageing Japanese sea bass ( Lateolabrax japonicus ) larvae and juveniles. Samples were collected from the Tango Sea along the Japan Sea coast, January–March 2007. Known-age (0-day and 10-day-old) larvae were obtained from the Ibaragi Prefectural Hatchery, Japan. Sagittal and lapillar otolith were processed and read using an otolith reading system. Clearly discernible hatch- and first-feeding marks were evident on sagitta, and development of accessory premordia (AP) appeared to be associated with larva-juvenile transition; however, no other marks indicating metamorphosis or settlement were evident. In lapillus, no discernible check mark was found. Known-age larvae showed that deposition of the first daily increment (DI) corresponded to first-feeding, which occurred at day-4 post-hatch. However, mean increment counts were significantly lower in lapillus than in sagitta, caused by poorly expressed increments around the centrum as well as relatively unclear centrum of the lapillus. The authors suggest that the use of lapillus can cause significant underestimation of age. Therefore, the sagitta is recommended for age and growth estimations of larvae and juveniles, although the presence of numerous subdaily increments warrants careful preparation and interpretation of the microstructure. A test for asymmetry showed the right and left otoliths to be quite symmetrical and their DI counts not significantly different, suggesting that either otolith can be used for studying age and growth of Japanese sea bass larvae and juveniles.     

Novozym 435 for production of biodiesel from unrefined palm oil: Comparison of methanolysis methods

Biodiesel (BD) is commonly produced from refined vegetable oils by alkali-catalyzed methanolysis. Unrefined vegetable oils are economically attractive but not suitable for alkali catalysis because of their high content of free fatty acids (FFAs). Novozym 435 (immobilized Candida antarctica lipase B), which accepts both FFA and oil as substrates, was, therefore, employed to convert unrefined palm oil to BD. Three different methanolysis methods, namely, t-butanol mediated system (method-1), LiCl solution based controlled release system for methanol (method-2) and solvent-free system with three successive additions of methanol (method-3), were compared. The optimal methanol to oil molar ratios in the method-1, -2 and -3 are 6:1, 3:1 and 3:1, respectively. BD yield at an optimal methanol concentration reaches 91–92% after 10, 20 and 24 h in the method-1, -2 and -3, respectively. BD yield remains the same over five repeated cycles in the method-1, while it drops to 68 and 71% by the fifth cycle in the method-2 and -3, respectively. The results show that the method-1 is the most effective for production of BD from a low cost feedstock like unrefined palm oil.     

Diet and prey selection in larval and juvenile Japanese anchovy Engraulisjaponicus in Ariake Bay, Japan

We studied the diet of larval and juvenile Japanese anchovy Engraulis japonicus in the upper Ariake Bay, Japan. Diet was analyzed by examining the digestive tracts; feeding intensity, proportion of empty guts, and prey selectivity were calculated. Anchovy density was negatively influenced by temperature and positively by salinity and prey density. Diet was dominated by Acartia omorii, which was positively selected with two other copepods, Calanus sinicus and Pseudodiaptomus marinus. In contrast, Oithona davisae was highly dominant in the environment but was absent in anchovy guts; thus, this copepod was negatively selected, with two others, Tortanus derjugini and Sinocalanus sinensis. Overall, larger prey were positively selected and smaller ones were negatively selected; value of electivity index correlated negatively with prey size. Larvae [<18 mm of standard length (SL)] showed significantly lower feeding intensities and higher rates of empty guts than juveniles (≥18 mm SL). In juveniles, feeding intensity increased steadily as the fish grew in size, with a corresponding reduction in empty guts. Feeding intensity correlated positively and empty gut correlated negatively with fish size. We suggest that larger prey are important diets for postlarval Japanese anchovy in Ariake Bay.     

High levels of genetic variability and differentiation in hilsa shad, Tenualosa ilisha (Clupeidae, Clupeiformes) populations revealed by PCR-RFLP analysis of the mitochondrial DNA D-loop region

The hilsa shad, Tenualosa ilisha (Clupeidae, Clupeiformes) is an important anadromous clupeid species from the Western division of the Indo-Pacific region. It constitutes the largest single fishable species in Bangladesh. Information on genetic variability and population structure is very important for both management and conservation purposes. Past reports on the population structure of T. ilisha involving morphometric, allozyme and RAPD analyses are contradictory. We examined genetic variability and divergence in two riverine (the Jamuna and the Meghna), two estuarine (Kuakata and Sundarbans) and one marine (Cox's Bazar) populations of T. ilisha by applying PCR-RFLP analysis of the mtDNA D-loop region. The amplified PCR products were restricted with four restriction enzymes namely, XbaI, EcoRI, EcoRV, and HaeIII. High levels of haplotype and gene diversity within and significant differentiations among, populations of T. ilisha were observed in this study. Significant F(ST) values indicated differentiation among the river, estuary and marine populations. The UPGMA dendrogram based on genetic distance resulted in two major clusters, although, these were subsequently divided into three, corresponding to the riverine, estuarine and marine populations. The study underlines the usefulness of RFLP of mtDNA D-loop region as molecular markers, and detected at least two differentiated populations of T. ilisha in Bangladesh waters.     

A Role for Arabidopsis PUCHI in Floral Meristem Identity and Bract Suppression

At the onset of flowering, the Arabidopsis thaliana primary inflorescence meristem starts to produce flower meristems on its flank. Determination of floral fate is associated with changes in the growth pattern and expression of meristem identity genes and suppression of a subtending leaf called a bract. Here, we show a role in floral fate determination and bract suppression for the PUCHI gene, an AP2/EREBP family gene that has previously been reported to play roles in lateral root morphogenesis. Mutations in PUCHI cause partial conversion of flowers to inflorescences, indicating that PUCHI is required for flower meristem identity. PUCHI is transiently expressed in the early flower meristem and accelerates meristem bulging while it prevents the growth of the bract primordium. The function of PUCHI in floral fate determination and bract suppression overlaps that of the BLADE-ON-PETIOLE1 (BOP1) and BOP2 genes, which encode a pair of redundant regulatory proteins involved in various developmental processes, including leaf morphogenesis and flower patterning. We also show that PUCHI acts together with BOP1 and BOP2 to promote expression of LEAFY and APETALA1, two central regulators of floral meristem identity. Expression patterns of the PUCHI and BOP genes point to a role in spatial control of flower-specific activation of these meristem identity genes.     

Cost-Effectiveness Analysis of Combination Therapies for Visceral Leishmaniasis in the Indian Subcontinent

Background

Visceral leishmaniasis is a systemic parasitic disease that is fatal unless treated. We assessed the cost and cost-effectiveness of alternative strategies for the treatment of visceral leishmaniasis in the Indian subcontinent. In particular we examined whether combination therapies are a cost-effective alternative compared to monotherapies.

Methods and Findings

We assessed the cost-effectiveness of all possible mono- and combination therapies for the treatment of visceral leishmaniasis in the Indian subcontinent (India, Nepal and Bangladesh) from a societal perspective using a decision analytical model based on a decision tree. Primary data collected in each country was combined with data from the literature and an expert poll (Delphi method). The cost per patient treated and average and incremental cost-effectiveness ratios expressed as cost per death averted were calculated. Extensive sensitivity analysis was done to evaluate the robustness of our estimations and conclusions. With a cost of US$92 per death averted, the combination miltefosine-paromomycin was the most cost-effective treatment strategy. The next best alternative was a combination of liposomal amphotericin B with paromomycin with an incremental cost-effectiveness of $652 per death averted. All other strategies were dominated with the exception of a single dose of 10mg per kg of liposomal amphotericin B. While strategies based on liposomal amphotericin B (AmBisome) were found to be the most effective, its current drug cost of US$20 per vial resulted in a higher average cost-effectiveness. Sensitivity analysis showed the conclusion to be robust to variations in the input parameters over their plausible range.

Conclusions

Combination treatments are a cost-effective alternative to current monotherapy for VL. Given their expected impact on the emergence of drug resistance, a switch to combination therapy should be considered once final results from clinical trials are available.     

Proteome analysis in adipose tissue of <Emphasis Type="Italic">ob/ob</Emphasis> mice in response to chitosan oligosaccharides treatment

Adipose tissue plays a central role in the development of obesity, and thus characterization of the molecular changes related to obesity in this tissue is a main concern. Recently we identified chitosan oligosaccharides (CO) as a potent adipogenic inhibitor in 3T3-L1 cells. In the current study, a proteomic approach was used to investigate the anti-obesity effect of CO in white adipose tissue of ob/ob mice. CO administration significantly lowered body weight gain and epididymal WAT mass compared to control animals. In addition, twenty-five proteins were found to be differentially expressed between the two groups of animals in response to CO treatment. Expression changes in Karyopherin beta 1, indoleamine-pyrrole 2,3-dioxygenase, and retinoic acid binding protein were associated here for the first time with obesity. Immunoblotting studies of adipocyte protein 2 (aP2) and aquaporin-7 also showed amelioration in their levels in WAT. Furthermore, the results of adipose tissue specific gene expressions of aP2, adiponectin, TNF-α, and IL-6 were in good agreement with improved levels of obesity. Gene expression of PPARg and SREBP-1c were also down-regulated by CO treatment. The results suggest that the anti-obesity effect of CO might be mediated by the modulation of adipokines and adipose tissue specific genes.