Mito-nuclear genetic comparison in a Wolbachia infected weevil: insights on reproductive mode, infection age and evolutionary forces shaping genetic variation

<p>Abstract</p> <p>Background</p> <p>Maternally inherited endosymbionts like <it>Wolbachia pipientis </it>are in linkage disequilibrium with the mtDNA of their hosts. Therefore, they can induce selective sweeps, decreasing genetic diversity over many generations. This sex ratio distorter, that is involved in the origin of parthenogenesis and other reproductive alterations, infects the parthenogenetic weevil <it>Naupactus cervinus</it>, a serious pest of ornamental and fruit plants.</p> <p>Results</p> <p>Molecular evolution analyses of mitochondrial (<it>COI</it>) and nuclear (<it>ITS1</it>) sequences from 309 individuals of <it>Naupactus cervinus </it>sampled over a broad range of its geographical distribution were carried out. Our results demonstrate lack of recombination in the nuclear fragment, non-random association between nuclear and mitochondrial genomes and the consequent coevolution of both genomes, being an indirect evidence of apomixis. This weevil is infected by a single <it>Wolbachia </it>strain, which could have caused a moderate bottleneck in the invaded population which survived the initial infection.</p> <p>Conclusions</p> <p>Clonal reproduction and <it>Wolbachia </it>infection induce the coevolution of bacterial, mitochondrial and nuclear genomes. The time elapsed since the <it>Wolbachia </it>invasion would have erased the traces of the demographic crash in the mtDNA, being the nuclear genome the only one that retained the signal of the bottleneck. The amount of genetic change accumulated in the mtDNA and the high prevalence of <it>Wolbachia </it>in all populations of <it>N. cervinus </it>agree with the hypothesis of an ancient infection. <it>Wolbachia </it>probably had great influence in shaping the genetic diversity of <it>N. cervinus</it>. However, it would have not caused the extinction of males, since sexual and asexual infected lineages coexisted until recent times.</p

Fabrication and magnetic properties of hard/soft magnetostatically coupled FePt/FeNi multilayer microwires

3 pages, 5 figures.-- PACS: 75.70.Cn; 75.60.Ej; 75.50.Ww; 81.15.Pq; 68.65.Ac; 81.40.EfA family of multilayer microwires with hard/soft biphase magnetic behavior is here introduced. The microwires consist of a Fe63Pt27Si10 hard magnetic nucleus and a Fe20Ni80 soft outer shell separated by an intermediate insulating Pyrex glass microtube. The precursor FePtSi glass-coated microwire is fabricated by quenching and drawing technique, and its L10 hard magnetic phase is grown by postannealing treatment technique. The polycrystalline FeNi soft magnetic outer shell has been deposited by electroplating. The analysis of the low-field hysteresis loops of the FeNi soft phase after premagnetizing until near magnetic saturation provides information about the magnetostatic coupling between phases. The FeNi magnetization curve is shifted toward positive field when the FePt remanent magnetization is positive and vice versa. A systematic analysis of the magnetostatic coupling and the corresponding bias field arising from uncompensated poles of the premagnetized FePt hard phase has been performed. The strength of the bias field is shown to increase with the reduction of thickness of the FeNi layer. These magnetostatically coupled biphase systems are thought to be of large potential interest as sensing elements in sensor devices.The work has been developed under the Project No. MAT2004-00150 supported by the Spanish Ministry of Education and Science, MEC. J. T. acknowledges a FPU program fellowship from MEC.Peer reviewe

Exon 3 of the NUMB Gene Emerged in the Chordate Lineage Coopting the NUMB Protein to the Regulation of MDM2

MDM2 regulates a variety of cellular processes through its dual protein:protein interaction and ubiquitin ligase activities. One major function of MDM2 is to bind and ubiquitinate P53, thereby regulating its proteasomal degradation. This function is in turn controlled by the cell fate determinant NUMB, which binds to and inhibits MDM2 via a short stretch of 11 amino acids, contained in its phosphotyrosine-binding (PTB) domain, encoded by exon 3 of the NUMB gene. The NUMB-MDM2-P53 circuitry is relevant to the specification of the stem cell fate and its subversion has been shown to be causal in breast cancer leading to the emergence of cancer stem cells. While extensive work on the evolutionary aspects of the MDM2/P53 circuitry has provided hints as to how these two proteins have evolved together to maintain conserved and linked functions, little is known about the evolution of the NUMB gene and, in particular, how it developed the ability to regulate MDM2 function. Here, we show that NUMB is a metazoan gene, which acquired exon 3 in the common ancestor of the Chordate lineage, first being present in the Cephalochordate and Tunicate subphyla, but absent in invertebrates. We provide experimental evidence showing that since its emergence, exon 3 conferred to the PTB domain of NUMB the ability to bind and to regulate MDM2 functions

Efficacy of spermatic vein ligation in patients affected by high grade left varicocele.

Purpose: To study the effect of high grade varicocele treatment in infertile patients. Materials and Methods: Seventy-five patients were selected by the following criteria: infertility persisting for more than 1 year; abnormal semen parameters; no other infertility-related disease; no obvious causes of infertility in the subject's partner; basal eco-color Doppler ultrasound demonstrating continuous reflux in the spermatic vein. All patients considered for the study had at least a six months period from the diagnosis to the surgery due to waiting list, choice of the patient or time needed to complete diagnostic evaluation of the couple. The surgical procedure was performed through an inguinal approach. All enrolled patients were counseled to have unprotected intercourse during the ovulation period in order to maximize the probability of pregnancy within the 6-month preoperative period. The achievement of pregnancy and semen parameters were recorded during the preoperative and postoperative period. Results: Two of the seventy-five patients were excluded because of persistent varicocele after surgery. The preoperative pregnancy rate was 1.3% (1 couple). The postoperative pregnancy rate was 42.5%. The stratification of pregnancies by semester showed a significantly higher rate in the first postoperative period (p = 0.0012). Mean time to conception was 13.5 months. Mean preoperative sperm count was 17.6x10 6 /mL compared to 19.7x10 6 /mL in the postoperative period (p < 0.0001). Mean percentage of progressive sperm motility was 13.7%, compared to 17.6% in the postoperative period (p < 0.0001). Mean percentage of normal sperm morphology was 7.6%, compared to 15.2% postoperatively (p < 0.0001). Conclusion: Surgical treatment of high grade varicocele proved to effectively treat associated infertility by improving seminal parameters and pregnancy rate in our patient cohort

Species delimitation in the Andean grasshopper genus <i>Orotettix</i> Ronderos & Carbonell (Orthoptera: Melanoplinae): an integrative approach combining morphological, molecular and biogeographical data

The reciprocal illumination nature of integrative taxonomy through hypothesis testing, corroboration and revision is a powerful tool for species delimitation as more than one source has to support the hypothesis of a new species. In this study, we applied an integrative taxonomy approach combining molecular and morphological data sets with distributional patterns to examine the level of differentiation between and within the grasshopper Orotettix species. Orotettix was described based on five valid species distributed in the Andes of Peru. In our study, initially a molecular-based hypothesis was postulated and tested against morphological data and geographical patterns of distribution. Results from molecular and morphological analyses showed agreement among the species delimitation in Orotettix, and were also consistent with the geographical distribution. The analyses allowed us to delimit five new species for the genus (O. lunatus sp. nov., O.astreptos sp. nov., O. colcaensis sp. nov., O.paucartambensis sp. nov. and O.dichrous sp. nov.) from the Eastern and Western Cordilleras of Peru. We also provide critical knowledge on the phylogenetic relationships and distribution of the genus and conduct a revision of Orotettix.Facultad de Ciencias Naturales y MuseoCentro de Estudios Parasitológicos y de Vectore

Efficacy of free glutathione and niosomal glutathione in the treatment of acetaminophen-induced hepatotoxicity in cats

Acetaminophen (APAP) administration results in hepatotoxicity and hematotoxicity in cats. The response to three different treatments against APAP poisoning was evaluated. Free glutathione (GSH) (200mg/kg), niosomal GSH (14 mg/kg) and free amino acids (180 mg/kg of N-acetylcysteine and 280 mg/kg of methionine) were administered to cats that were intoxicated with APAP (a single dose of 150 mg/kg, p.o.). Serum concentration of alanine aminotransferase (ALT) along with serum, liver and erythrocyte concentration of GSH and methemoglobin percentage were measured before and 4, 24 and 72 hours after APAP administration. Free GSH (200 mg/kg) and niosomal GSH (14 mg/kg) were effective in reducing hepatotoxicity and hematotoxicity in cats intoxicated with a dose of 150 mg/kg APAP. We conclude that both types of treatments can protect the liver and haemoglobin against oxidative stress in APAP intoxicated cats. Furthermore, our results showed that treatment with niosomal GSH represents an effective therapeutic approach for APAP poisoning.Fil: Denzoin Vulcano, L. A.. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Fisiopatologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; ArgentinaFil: Confalonieri, O.. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Clinicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; ArgentinaFil: Franci, R.. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Clinicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; ArgentinaFil: Tapia, Maria Ofelia. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Fisiopatologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; ArgentinaFil: Soraci, Alejandro Luis. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Veterinarias. Departamento de Fisiopatologia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; Argentin

Are flightless Galapaganus weevils older than the Galapagos islands they inhabit?

The 15 species in the weevil genus Galapaganus Lanteri 1992 (Entiminae: Curculionidae: Coleoptera) are distributed on coastal Peril and Ecuador and include 10 flightless species endemic to the Galapagos islands. These beetles thus provide a promising system through which to investigate the patterns and processes of evolution on Darwin's archipelago. Sequences of the mtDNA locus encoding cytochrome oxidase subunit I (COI) were obtained from samples of seven species occurring in different ecological zones of the oldest south-eastern islands: San Cristobal, Espanola and Floreana, and the central island Santa Cruz. The single most parsimonious tree obtained shows two well-supported clades that correspond to the species groups previously defined by morphological characters. Based on a mtDNA clock calibrated for arthropods, the initial speciation separating the oldest species, G. galapagoensis (Linell) on the oldest island, San Cristobal, from the remaining species in the Galapagos occurred about 7.2 Ma. This estimate exceeds geological ages of the extant emerged islands, although it agrees well with molecular dating of endemic Galapagos iguanas, geckos and lizards. An apparent explanation for the disagreement between geological and molecular time-frames is that about 7 Ma there were emerged islands which subsequently disappeared under ocean waters. This hypothesis has gained support from the recent findings of 11 -Myr-old submarine seamounts (sunken islands), south-east of the present location of the archipelago. Some species within the darwini group may have differentiated on the extant islands, 1-5 Ma.Facultad de Ciencias Naturales y Muse

Are flightless Galapaganus weevils older than the Galapagos islands they inhabit?

The 15 species in the weevil genus Galapaganus Lanteri 1992 (Entiminae: Curculionidae: Coleoptera) are distributed on coastal Peril and Ecuador and include 10 flightless species endemic to the Galapagos islands. These beetles thus provide a promising system through which to investigate the patterns and processes of evolution on Darwin's archipelago. Sequences of the mtDNA locus encoding cytochrome oxidase subunit I (COI) were obtained from samples of seven species occurring in different ecological zones of the oldest south-eastern islands: San Cristobal, Espanola and Floreana, and the central island Santa Cruz. The single most parsimonious tree obtained shows two well-supported clades that correspond to the species groups previously defined by morphological characters. Based on a mtDNA clock calibrated for arthropods, the initial speciation separating the oldest species, G. galapagoensis (Linell) on the oldest island, San Cristobal, from the remaining species in the Galapagos occurred about 7.2 Ma. This estimate exceeds geological ages of the extant emerged islands, although it agrees well with molecular dating of endemic Galapagos iguanas, geckos and lizards. An apparent explanation for the disagreement between geological and molecular time-frames is that about 7 Ma there were emerged islands which subsequently disappeared under ocean waters. This hypothesis has gained support from the recent findings of 11 -Myr-old submarine seamounts (sunken islands), south-east of the present location of the archipelago. Some species within the darwini group may have differentiated on the extant islands, 1-5 Ma.Facultad de Ciencias Naturales y Muse