Dimethoate Induces Kidney Dysfunction, Disrupts Membrane-Bound ATPases and Confers Cytotoxicity Through DNA Damage. Protective Effects of Vitamin E and Selenium

Dimethoate (DM) is an organophosphate insecticide widely used in agriculture and industry and has toxic effects on non-target organisms especially mammalian. However, we still know little about DM-induced kidney injury and its alleviation by natural antioxidants. In the present study, selenium (Se), vitamin E, DM, Se+DM, vitamin E+DM, Se+vitamin E+DM were given to adult rats for 4 weeks. Plasma creatinine and uric acid, kidney MDA, PC, H₂O₂ and AOPP levels were higher, while Na⁺-K⁺-ATPase and LDH values were lower in the DM group than those of controls. A smear without ladder formation on agarose gel was shown in the DM group, indicating random DNA degradation and DM-induced genotoxicity. A decrease in kidney GSH, NPSH and plasma urea levels and an increase in GPx, SOD and catalase activities were observed in the DM group when compared to those of controls. Plasma cystatin C levels increased, indicating a decrease in glomerular filtration rate. When Se or vitamin E was added through diet, the biochemical parameters cited above were partially restored in Se+DM and vitamin E+DM than DM group. The joint effect of Se and vitamin E was more powerful against DM-induced oxidative stress and kidney dysfunction. The changes in biochemical parameters were substantiated by histological data. In conclusion, our results indicated a possible mechanism of DM-induced nephrotoxicity, where renal genotoxicity was noted, membrane-bound ATPases and plasma biomarkers were disturbed. Se and vitamin E ameliorated the toxic effects of this pesticide in renal tissue suggesting their role as potential antioxidants.     

The Xenopus TRPV6 homolog encodes a Mg2+‐permeant channel that is inhibited by interaction with TRPC1

The TRP gene family encodes primarily cation non‐selective, Ca²⁺ permeant channels that are involved in a dizzying array of sensory mechanisms. Two channels in this large family TRPV5 and TRPV6 are highly Ca²⁺ selective and are expressed in epithelia where they are important in Ca²⁺ uptake. TRPV5/6 are constitutively active, yet the mechanisms regulating their activation in native tissue remains elusive. Here we functionally characterize the Xenopus TRPV6 homolog. xTRPV6 is expressed in the oocyte and encodes a channel that is permeant to divalents including Ca²⁺, and displays a high permeability to Mg²⁺. The oocyte does not exhibit functional TRPV6‐like current at rest, showing that the endogenous channel is somehow maintained in an inactive state. We show that endogenous as well as overexpressed xTRPV6 interacts with xTRPC1 and that this interaction inhibits xTRPV6 currents. As such TRPC1 is likely to regulate the activity of TRPV6 under physiological conditions. J. Cell. Physiol. 228: 2386–2398, 2013. © 2013 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.     

Cole Disease Results from Mutations in ENPP1

The coexistence of abnormal keratinization and aberrant pigmentation in a number of cornification disorders has long suggested a mechanistic link between these two processes. Here, we deciphered the genetic basis of Cole disease, a rare autosomal-dominant genodermatosis featuring punctate keratoderma, patchy hypopigmentation, and uncommonly, cutaneous calcifications. Using a combination of exome and direct sequencing, we showed complete cosegregation of the disease phenotype with three heterozygous ENPP1 mutations in three unrelated families. All mutations were found to affect cysteine residues in the somatomedin-B-like 2 (SMB2) domain in the encoded protein, which has been implicated in insulin signaling. ENPP1 encodes ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), which is responsible for the generation of inorganic pyrophosphate, a natural inhibitor of mineralization. Previously, biallelic mutations in ENPP1 were shown to underlie a number of recessive conditions characterized by ectopic calcification, thus providing evidence of profound phenotypic heterogeneity in ENPP1-associated genetic diseases.     

Microbial analysis of cucumbers (Cucumis sativus) produced with tap or treated waste water

There is increasing evidence for a significant role of fruits and vegetables in infectious diseases in humans. Their consumption is increasing and environmental factors such as water availability are impacting their production. In this study, adding fertiliser to tap water (TW) increased the microbial load above that found in treated waste water (TWW); coliforms were also introduced. Low numbers of Bacillus spp. were recovered from inside some healthy cucumber fruits. No visible differences were observed between cucumber plants irrigated with TWW or TW or cucumbers with and without endophytic Bacillus spp. This is noteworthy when considering the use of TWW for crop irrigation.     

Morphology,ontogeny, and molecular phylogeny of two novel bakuellid-like hypotrichs (Ciliophora: Hypotrichia), with establishment of two new genera

The morphology, ontogeny and molecular phylogeny of Apobakuella fusca gen. n., sp. n. and Parabistichella variabilis gen. n., sp. n., from south China were investigated. Apobakuella fusca, brown colored, demonstrates bakuellid-like infraciliature, and a similar ontogenesis as the genus Bakuella. It is argued, however, that this species represents a novel genus, Apobakuella, which is characterized by two or more marginal rows on the right, several buccal and parabuccal cirri, and lack of frontoterminal and caudal cirri. Phylogenetic analysis based on SSU rRNA gene sequences supports the close relationship of Apobakuella with Neobakuella and Diaxonella within the core Urostylida. By contrast, Parabistichella variabilis has a dominant frontoventral row, few midventral pairs, a long midventral row, and one marginal row on each side. Its morphogenesis exhibits: (1) partial reorganization of the parental adoral membranelles; (2) over six frontoventral-transverse cirri anlagen; (3) intrakinetal development of the midventral row; and (4) very likely, formation of the frontoventral row from the midventral row anlage. Both the morphological characteristics and the SSU rRNA gene sequences suggest that it is incertae sedis among the basal hypotrichs. Further investigation of key taxa with additional molecular markers is required to reveal a better understanding on the phylogeny of Parabistichella.     

Morphology,ontogeny and molecular phylogeny of a new brackish water ciliate Bakuella subtropica sp. n. (Ciliophora,Hypotricha) from southern China

This paper investigates the morphology, ontogenesis and small subunit (SSU) rRNA gene-based phylogeny of a new urostylid ciliate, Bakuella subtropica sp. n., discovered from the estuary of the Pearl River in Guangzhou, southern China. The new species is diagnosed by its elongate body, one buccal and one parabuccal cirrus, midventral complex comprised of 9–23 midventral pairs and one or two midventral rows extending to four fifths of body length, yellow-brown to yellow-greenish cortical granules and an estuary habitat. Its main ontogenetic features are: (1) in the proter, the parental adoral zone of membranelles is completely renewed by new structures and old midventral pairs join the formation of frontal-midventral-transverse cirral anlagen (FVT-anlagen); (2) in the opisthe, the oral primordium originates apokinetally, FVT-anlagen are formed besides and some old midventral cirri join the formation; (3) the anlagen for marginal rows and dorsal kineties develop intrakinetally; and (4) the numerous macronuclear nodules fuse into a single mass before dividing. Based on the SSU rDNA sequences, phylogenetic analyses show a close relationship between Bakuella subtropica sp. n., Apobakuella and Neobakuella, forming a clade separated from the other genera in the family Bakuellidae. Available morphological and ontogenetic data challenge the monophyly of Bakuellidae.     

Morphology of three new marine Frontonia species (Ciliophora; Peniculida) with note on the phylogeny of this genus

Members of the ciliate genus Frontonia are common colonizers of periphytic communities in aquatic biotopes. Recent studies indicate that their species diversity is higher than previously supposed. In this study the morphology and infraciliature of three new species, Frontonia sinica spec. nov., F. pusilla spec. nov., and F. elegans spec. nov., isolated from coastal waters of China, were investigated using live observation and silver impregnation methods. Frontonia sinica differs from its congeners by the following combination of characters: ellipsoidal body, about 116 somatic and five or six vestibular kineties, peniculi 1 and 2 four-rowed, peniculus 3 two-rowed, and a single contractile vacuole. Frontonia pusilla has about 72 somatic kineties, four-rowed peniculi 1 and 2, a two-rowed peniculus 3, and two contractile vacuoles. Frontonia elegans has 73 somatic kineties, four-rowed peniculi 1 and 2, a three-rowed peniculus 3, and two contractile vacuoles. In the present work, six new small-subunit rRNA gene sequences of six Frontonia species are used to construct the phylogenetic trees. Our phylogenetic analysis supports that the genus Frontonia may be paraphyletic. Meanwhile, no pattern of correlation could be found between the structures of peniculi and the phylogenetic relationships of Frontonia species in the present study.