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1.
Sci Total Environ ; 946: 174396, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38950634

RESUMEN

Salt marsh has an important 'purification' role in coastal ecosystems by removing excess nitrogen that could otherwise harm aquatic life and reduce water quality. Recent studies suggest that salt marsh root exudates might be the 'control centre' for nitrogen transformation, but empirical evidence is lacking. Here we sought to estimate the direction and magnitude of nitrogen purification by salt marsh root exudates and gain a mechanistic understanding of the biogeochemical transformation pathway(s). To achieve this, we used a laboratory incubation to quantify both the root exudates and soil nitrogen purification rates, in addition to the enzyme activities and functional genes under Phragmites australis populations with different nitrogen forms addition (NO3-, NH4+ and urea). We found that NO3- and urea addition significantly stimulate P. australis root exudation of total acids, amino acids, total sugars and total organic carbon, while NH4+ addition only significantly increased total acids, amino acids and total phenol exudation. High total sugars, amino acids and total organic carbon concentrations enlarged nitrogen purification potential by stimulating the nitrogen purifying bacterial activities (including enzyme activities and related genes expression). Potential denitrification rates were not significantly elevated under NH4+ addition in comparison to NO3- and urea addition, which should be ascribed to total phenol self-toxicity and selective inhibition. Further, urea addition stimulated urease and protease activities with providing more NH4+ and NO2- substrates for elevated anaerobic ammonium oxidation rates among the nitrogen addition treatments. Overall, this study revealed that exogenous nitrogen could increase the nitrogen purification-associated bacterial activity through accelerating the root exudate release, which could stimulate the activity of nitrogen transformation, and then improve the nitrogen removal capacity in salt marsh.


Asunto(s)
Nitrógeno , Raíces de Plantas , Suelo , Humedales , Nitrógeno/metabolismo , Raíces de Plantas/metabolismo , Suelo/química , Poaceae , Exudados de Plantas , Desnitrificación
2.
Arch Virol ; 166(8): 2333-2335, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34075444

RESUMEN

The complete genome sequence of a novel iflavirus isolated from the gregarious and koinobiont endoparasitoid Tetrastichus brontispae, tentatively named "Tetrastichus brontispae RNA virus 3" (TbRV-3), was determined by total RNA and Sanger sequencing. The complete genome is 9998 nucleotides in length, 8934 nt of which encodes a putative polyprotein of 2978 amino acids. TbRV-3 was found to have a similar genome organization and to contain conserved domains and motifs found in other iflaviruses, with some variations. Phylogenetic analysis based on deduced amino acid sequences of the RdRp domain showed that TbRV-3 clustered with Dinocampus coccinellae paralysis virus (DcPV). However, the percent amino acid sequence identity of the putative capsid proteins of TbRV-3 and DcPV determined using BLASTp was below the species demarcation threshold (90%), suggesting that TbRV-3 is a new iflavirus. This is the first virus of the family Iflaviridae to be isolated from a wasp of the family Eulophidae.


Asunto(s)
Virus de Insectos/clasificación , Avispas/virología , Secuenciación Completa del Genoma/métodos , Secuencia de Aminoácidos , Animales , Tamaño del Genoma , Genoma Viral , Virus de Insectos/genética , Virus de Insectos/aislamiento & purificación , Sistemas de Lectura Abierta , Filogenia , Análisis de Secuencia de ARN
3.
Tob Induc Dis ; 19: 34, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33994906

RESUMEN

INTRODUCTION: Cigarette smoking has been hypothesized to be a risk factor for meningioma. However, the results of studies exploring the relationship between smoking exposure and the occurrence of meningioma are inconsistent. METHODS: A search of PubMed, Medline, Embase, and Science Direct (up to June 2020) databases was performed. Two authors independently extracted the data. The Newcastle-Ottawa Scale was employed for judging the quality of articles. A random-effects model was utilized for meta-analysis. Association analysis between smoking and meningioma was based on the adjusted RR and the 95% CI, as reported by eligible studies. Subgroup and sensitivity analyses were performed and publication bias was assessed. Subgroup analysis was conducted by geographical region, study design, sex, study quality, and adjustments of RR score. Begg's and Egger's tests were employed for detecting publication bias. RESULTS: Twelve articles, including 2 cohort studies and 10 case-control studies, and a total of 1210167 participants were identified. The pooled relative risk (RR) with 95% confidence interval (95% CI) implied that smoking was not associated with increased risk of meningioma in men and women combined (RR=1.09; 95% CI: 0.90-1.33). From the sex-stratified subgroup analysis, the risk of meningioma was significant in men (RR=1.42; 95% CI: 1.16-1.74). Risk of meningioma in women did not remain significant (RR=0.92; 95% CI: 0.73-1.16). There was a high heterogeneity in the results (I2=58.4%, p=0.002). Sensitivity analyses showed stable results and there was no evidence of publication bias. CONCLUSIONS: Cigarette smoking is not associated with a significantly increased risk of meningioma in the whole population, but there is a positive association in men but not in women.

4.
Neurol Sci ; 41(1): 35-40, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31578652

RESUMEN

Lead is a known risk factor for amyotrophic lateral sclerosis (ALS). However, the results of studies exploring the relationship between lead exposure and the occurrence of ALS are inconsistent. To clarify this issue, we conducted a systematic review and meta-analysis of relevant published articles on the relationship between lead exposure and the occurrence of ALS. We searched the PubMed, MEDLINE, Embase, and Science Direct databases for relevant publications. The quality of the articles was judged according to the Newcastle-Ottawa scale, and the meta-analysis was conducted using a random effect model. A total of 583 items were retrieved of which 11 case-control studies were selected. The ratio of maximal/minimal lead exposure yielded a pooled odds ratio (OR) of 1.46 (95% confidence interval (CI) 1.16-1.83) with moderate heterogeneity (I2 = 51.8%; p = 0.019). Subgroup and sensitivity analyses showed stable results. There was evidence of publication bias, but the recalculated OR after employing the "fill and trim" method was 1.28 (95% CI 1.02-1.63). These results indicated that environmental/occupational lead exposure was positively proportional to the risk of ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral/inducido químicamente , Esclerosis Amiotrófica Lateral/epidemiología , Exposición a Riesgos Ambientales/efectos adversos , Plomo/efectos adversos , Exposición Profesional/efectos adversos , Vigilancia de la Población , Esclerosis Amiotrófica Lateral/diagnóstico , Estudios de Casos y Controles , Humanos , Vigilancia de la Población/métodos , Factores de Riesgo
5.
Viruses ; 11(3)2019 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-30871248

RESUMEN

The complete sequence of a novel RNA virus isolated from Tetrastichus brontispae (TbRV-1) was determined to be 12,239 nucleotides in length with five non-overlapping, linearly arranged coding sequences (CDS), potentially encoding nucleoproteins, hypothetical proteins, matrix proteins, glycoproteins, and RNA-dependent RNA polymerases. Sequence analysis indicated that the RNA-dependent RNA polymerase of TbRV-1 shares a 65% nucleotide and 67% amino acid sequence identity with Hubei dimarhabdovirus 2, suggesting that TbRV-1 is a member of the dimarhabdovirus supergroup. This corresponded to the result of the phylogenetic analysis. The affiliation of TbRV-1 with members of the family Rhabdoviridae was further validated by similar transcription termination motifs (GGAACUUUUUUU) to the Drosophila sigmavirus. The prevalence of TbRV-1 in all tissues suggested that the virus was constitutive of, and not specific to, any wasp tissue. To our knowledge, this is the first report on the complete genome sequence of a dimarhabdovirus in parasitoids.


Asunto(s)
Genoma Viral , Himenópteros/virología , Filogenia , Virus ARN/genética , Animales , Virus ARN/clasificación , Virus ARN/aislamiento & purificación , ARN Viral/genética , Proteínas Virales/genética , Secuenciación Completa del Genoma
6.
Bull Entomol Res ; 109(2): 248-256, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30514411

RESUMEN

Although parasites and microbial pathogens are both detrimental to insects, little information is currently available on the mechanism involved in how parasitized hosts balance their immune responses to defend against microbial infections. We addressed this in the present study by comparing the immune response between unparasitized and parasitized pupae of the chrysomelid beetle, Octodonta nipae (Maulik), to Escherichia coli invasion. In an in vivo survival assay, a markedly reduced number of E. coli colony-forming units per microliter was detected in parasitized pupae at 12 and 24 h post-parasitism, together with decreased phagocytosis and enhanced bactericidal activity at 12 h post-parasitism. The effects that parasitism had on the mRNA expression level of selected antimicrobial peptides (AMPs) of O. nipae pupae showed that nearly all transcripts of AMPs examined were highly upregulated during the early and late parasitism stages except defensin 2B, whose mRNA expression level was downregulated at 24 h post-parasitism. Further elucidation on the main maternal fluids responsible for alteration of the primary immune response against E. coli showed that ovarian fluid increased phagocytosis at 48 h post-injection. These results indicated that the enhanced degradation of E. coli in parasitized pupae resulted mainly from the elevated bactericidal activity without observing the increased transcripts of target AMPs. This study contributes to a better understanding of the mechanisms involved in the immune responses of a parasitized host to bacterial infections.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/metabolismo , Escarabajos/inmunología , Interacciones Huésped-Parásitos , Fagocitosis , Avispas/fisiología , Animales , Escarabajos/metabolismo , Escarabajos/parasitología , Pupa/inmunología , Pupa/metabolismo , Pupa/parasitología , Venenos de Avispas
7.
J Proteomics ; 192: 37-53, 2019 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-30098407

RESUMEN

The venom apparatus is a conserved organ in parasitoids that shows adaptations correlated with life-style diversification. Combining transcriptomics and label-free quantitative proteomics, here we explored the venom apparatus components of the endoparasitoid Tetrastichus brontispae (Eulophidae), and provide a comparison of the venom apparatus proteomes between its two closely related strains, T. brontispae-Octodonta nipae (Tb-On) and T. brontispae-Brontispa longissima (Tb-Bl). Tb-Bl targets the B. longissima pupa as its habitual host. However, Tb-On is an experimental derivative of Tb-Bl, which has been exposed to the O. nipae pupa as host consecutively for over 40 generation. Results showed that approximately 1505 venom proteins were identified in the T. brontispae venom apparatus. The extracts contained novel venom proteins, such as 4-coumarate-CoA ligase 4. A comparative venom proteome analysis revealed that significant quantitative and qualitative differences in venom composition exist between the two strains; although the most abundant venom proteins were shared between them. The differentially produced proteins were mainly enriched in fatty acid biosynthesis and melanotic encapsulation response. Six of these enriched proteins presented increased levels in Tb-On, and this result was validated by parallel reaction monitoring (PRM) analysis. Overall, our data reveal that venom composition can evolve quickly and respond to host selection.


Asunto(s)
Venenos de Artrópodos/metabolismo , Escarabajos/parasitología , Perfilación de la Expresión Génica , Himenópteros/metabolismo , Proteínas de Insectos/metabolismo , Proteómica , Animales , Pupa/metabolismo , Especificidad de la Especie
8.
J Insect Physiol ; 109: 125-137, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30025717

RESUMEN

Although the importance of parasitoids as biocontrol agents has long been recognized, systematic studies of the physiological mechanisms are scarce, especially in those parasitoids that are able to successfully invade their hosts by activating host immune responses. This study explored this phenomenon by investigating the effects of ovarian fluid, venom and egg surface characteristics of Tetrastichus brontispae (Hymenoptera: Eulophidae) on host immunity. The results showed that the injection of venom alone induced higher phenoloxidase activity, while a mixture of ovarian plus venom fluids provoked higher granulocyte and plasmatocyte spreading ratios, highlighting the role that egg surface characteristics may play in successful parasitism. After thorough investigation, the presence of a hemomucin homologue was documented on the egg surface (which was named Tetrastichus brontispae adipocyte plasma membrane associated protein-like, TbAPMAP-like), while the absence of polydnaviruses, fibrous layers and virus-like filaments was confirmed. The higher encapsulation index of eggs incubated with TbAPMAP-like polyclonal antibody demonstrated the protection of the protein against encapsulation. These results contribute to our understanding of the mechanisms used by endoparasitoids to evade encapsulation during the early parasitism stage while enriching our knowledge of local active regulatory mechanisms. It is likely that this is the first study to determine the egg protective properties of TbAPMAP-like in host-parasite systems.


Asunto(s)
Escarabajos/inmunología , Escarabajos/parasitología , Avispas/química , Avispas/fisiología , Animales , Venenos de Artrópodos/toxicidad , Escarabajos/efectos de los fármacos , Femenino , Mucinas , Ovario/química , Óvulo
10.
Artículo en Inglés | MEDLINE | ID: mdl-27101988

RESUMEN

Most studies on the contribution of the altered immune response by endoparasitoid have been restricted to the interactions between Ichneumonoidea and their hosts, while effects of parasitism by Chalcidoidea on the hosts have rarely been characterized except some wasps such as Pteromalidae. Endoparasitoid Tetrastichus brontispae Ferrière, belonging to Eulophidae (Hymenoptera), has a great potential to control some Coleopteran beetles such as Octodonta nipae, one invasive species in southern China. However, the physiological mechanism underlying the escape from the melanotic encapsulation in O. nipae pupae has not been demonstrated. In the present study, effects of parasitism on the immune function of its pupal host O. nipae were investigated. The combining results that granulocytes and plasmatocytes could phagocytize bacteria from 2 to 48h and granulocytes, plasmatocytes and oenocytoids were prophenoloxidase/phenoloxidase positive hemocytes indicated that granulocytes, plasmatocytes and oenocytoids were the main immunocompetent hemocytes in O. nipae pupae. Parasitism by T. brontispae resulted in a significant increase in the percentage of hemocytes viability and spreading at 96h, growing percentage of granulocytes at 24h but no effects on the total hemocyte counts, and an enhanced phenoloxidase activity only at 12 and 72h while a significantly longer melanization time of the hemolymph at 96h following parasitism. These results indicate that mixtures of systemic active and local active regulation are used for T. brontispae to escape host encapsulation in O. nipae pupae. The present study contributes to the understanding of the diversity of virulence strategies used by parasitoids.


Asunto(s)
Escarabajos/inmunología , Escarabajos/parasitología , Interacciones Huésped-Parásitos/inmunología , Himenópteros/fisiología , Pupa/parasitología , Animales , Escarabajos/enzimología , Escarabajos/metabolismo , Granulocitos/citología , Granulocitos/inmunología , Hemocitos/citología , Hemocitos/inmunología , Melaninas/metabolismo , Monofenol Monooxigenasa/metabolismo
11.
Lab Chip ; 14(17): 3233-40, 2014 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-24903337

RESUMEN

Implantable electronic medical devices have achieved remarkable medical advances in the treatment of the most challenging conditions, starting with the introduction of the first implantable pacemaker in 1958. Increasing demand for innovation in existing and novel implantable devices is fuelled by the growing aging population and the increased prevalence of chronic diseases. This perspective article provides an overview of the implantable medical device ecosystem, highlights recent developments, and discusses challenges and opportunities for translation of new innovative implants enabled by microtechnologies and microfabrication.


Asunto(s)
Equipos y Suministros , Humanos
12.
PLoS One ; 9(3): e91482, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24614330

RESUMEN

The beetle Octodonta nipae (Maulik) (Coleoptera: Chrysomelidae) is a serious invasive insect pest of palm plants in southern China, and the endoparasitoid Tetrastichus brontispae Ferrière (Hymenoptera: Eulophidae) is a natural enemy of this pest that exhibits great ability in the biocontrol of O. nipae. For successful parasitism, endoparasitoids often introduce or secrete various virulence factors to suppress host immunity. To investigate the effects of parasitization by T. brontispae on the O. nipae immune system, the transcriptome of O. nipae pupae was analyzed with a focus on immune-related genes through Illumina sequencing. De novo assembly generated 49,919 unigenes with a mean length of 598 bp. Of these genes, 27,490 unigenes (55.1% of all unigenes) exhibited clear homology to known genes in the NCBI nr database. Parasitization had significant effects on the transcriptome profile of O. nipae pupae, and most of these differentially expressed genes were down-regulated. Importantly, the expression profiles of immune-related genes were significantly regulated after parasitization. Taken together, these transcriptome sequencing efforts shed valuable light on the host (O. nipae) manipulation mechanisms induced by T. brontispae, which will pave the way for the development of novel immune defense-based management strategies of O. nipae, and provide a springboard for further molecular analyses, particularly of O. nipae invasion.


Asunto(s)
Escarabajos/genética , Escarabajos/inmunología , Perfilación de la Expresión Génica , Himenópteros/fisiología , Especies Introducidas , Animales , Análisis por Conglomerados , Escarabajos/parasitología , Ontología de Genes , Genes de Insecto , Interacciones Huésped-Parásitos/genética , Anotación de Secuencia Molecular , Pupa/genética , Pupa/parasitología , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Especificidad de la Especie , Transcripción Genética
13.
J Neural Eng ; 10(4): 045002, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23723130

RESUMEN

OBJECTIVE: Reliable chronic recordings from implanted neural probes remain a significant challenge; current silicon-based and microwire technologies experience a wide range of biotic and abiotic failure modes contributing to loss of signal quality. APPROACH: A multi-prong alternative strategy with potential to overcome these hurdles is introduced that combines a novel three dimensional (3D), polymer-based probe structure with coatings. Specifically, the Parylene C sheath-based neural probe is coated with neurotrophic and anti-inflammatory factors loaded onto a Matrigel carrier to encourage the ingrowth of neuronal processes for improved recording quality, reduce the immune response, and promote improved probe integration into brain tissue for reliable, long-term implementation compared to its rigid counterparts. MAIN RESULTS: The 3D sheath structure of the probe was formed by thermal molding of a surface micromachined Parylene C microchannel, with electrode sites lining the interior and exterior regions of the lumen. Electrochemical characterization of the probes via cyclic voltammetry and electrochemical impedance spectroscopy was performed and indicated suitable electrode properties for neural recordings (1 kHz electrical impedance of ∼200 kΩ in vitro). A novel introducer tool for the insertion of the compliant polymer probe into neural tissue was developed and validated both in vitro using agarose gel and in vivo in the rat cerebral cortex. In vivo electrical functionality of the Parylene C-based 3D probes and their suitability for recording the neuronal activity over a 28-day period was demonstrated by maintaining the 1 kHz electrical impedance within a functional range (<400 kΩ) and achieving a reasonably high signal-to-noise ratio for detection of resolvable multi-unit neuronal activity on most recording sites in the probe. Immunohistochemical analysis of the implant site indicated strong correlations between the quality of recorded activity and the neuronal/astrocytic density around the probe. SIGNIFICANCE: The provided electrophysiological and immunohistochemical data provide strong support to the viability of the developed probe technology. Furthermore, the obtained data provide insights into further optimization of the probe design, including tip geometry, use of neurotrophic and anti-inflammatory drugs in the Matrigel coating, and placement of the recording sites.


Asunto(s)
Potenciales de Acción/fisiología , Corteza Cerebral/fisiología , Materiales Biocompatibles Revestidos/química , Electrodos Implantados , Electroencefalografía/instrumentación , Monitoreo Ambulatorio/instrumentación , Polímeros/química , Xilenos/química , Animales , Materiales Biocompatibles Revestidos/farmacología , Conductividad Eléctrica , Diseño de Equipo , Análisis de Falla de Equipo , Masculino , Ratas , Ratas Sprague-Dawley
14.
Inflamm Bowel Dis ; 19(8): 1671-80, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23749272

RESUMEN

BACKGROUND: Neutralizing autoantibodies (Abs) against granulocyte-macrophage colony-stimulating factor (GM-CSF Ab) have been associated with stricturing ileal Crohn's disease (CD) in a largely pediatric patient cohort (total 394, adult CD 57). The aim of this study was to examine this association in 2 independent predominantly adult inflammatory bowel disease patient cohorts. METHODS: Serum samples from 742 subjects from the NIDDK IBD Genetics Consortium and 736 subjects from Australia were analyzed for GM-CSF Ab and genetic markers. We conducted multiple regression analysis with backward elimination to assess the contribution of GM-CSF Ab levels and established CD risk alleles and smoking on ileal disease location in the 477 combined CD subjects from both cohorts. We also determined associations of GM-CSF Ab levels with complications requiring surgical intervention in combined CD subjects in both cohorts. RESULTS: Serum samples from patients with CD expressed significantly higher concentrations of GM-CSF Ab when compared with ulcerative colitis or controls in each cohort. Nonsmokers with ileal CD expressed significantly higher GM-CSF Ab concentrations in the Australian cohort (P = 0.002). Elevated GM-CSF Ab, ileal disease location, and disease duration more than 3 years were independently associated with stricturing/penetrating behavior and intestinal resection for CD. CONCLUSIONS: The expression of high GM-CSF Ab is a risk marker for aggressive CD behavior and complications including surgery. Modifying factors include environmental exposure to smoking and genetic risk markers.


Asunto(s)
Autoanticuerpos/sangre , Biomarcadores/sangre , Constricción Patológica/diagnóstico , Enfermedad de Crohn/diagnóstico , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Obstrucción Intestinal/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Autoanticuerpos/inmunología , Niño , Preescolar , Estudios de Cohortes , Constricción Patológica/sangre , Constricción Patológica/etiología , Enfermedad de Crohn/sangre , Enfermedad de Crohn/complicaciones , Femenino , Estudios de Seguimiento , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Humanos , Lactante , Recién Nacido , Obstrucción Intestinal/sangre , Obstrucción Intestinal/etiología , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Adulto Joven
15.
Neurourol Urodyn ; 31(4): 572-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22275213

RESUMEN

AIMS: We investigated the roles of neuronal-derived nitric oxide (NO) in the modulation of spontaneous activity of mouse detrusor smooth muscle. METHODS: Detrusor smooth muscle strips were isolated from nNOS gene knock-out (nNOS(-/-) ) mice and their wild type siblings (nNOS(+/+) ). The properties of smooth muscle cells were assessed using intracellular electrophysiology and Ca(2+) imaging by laser-scanning confocal microscopy. The effects of an nNOS inhibitor, 7-nitro indazole (7-NI) on electrically evoked contractility were assessed using nNOS(+/+) mouse detrusor strips. RESULTS: In spontaneously active cells, the frequency of spontaneous action potentials (sAPs) and whole cell Ca(2+) flashes in nNOS(-/-) preparations was lower than that in the nNOS(+/+) preparations. The frequency of sAPs was enhanced by a nitric oxide donor, diethylamine NONOate sodium salt (NONOate; 100 µM), both when used alone and when the cGMP pathway was blocked by 1H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one (ODQ, 10 µM). 7-NI (100 µM) significantly suppressed the electrically evoked contraction of mouse detrusor strips. CONCLUSIONS: We suggest that neuronal-derived NO facilitates the generation of spontaneous activity via a cGMP-independent pathway, and consequently enhances the evoked contraction of detrusor. Dysregulation of nNOS containing nerves may underlie bladder pathologies.


Asunto(s)
Músculo Liso/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Óxido Nítrico/metabolismo , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Animales , Señalización del Calcio/efectos de los fármacos , Femenino , Hidrazinas/farmacología , Masculino , Ratones , Ratones Noqueados , Contracción Muscular/efectos de los fármacos , Contracción Muscular/fisiología , Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Neuronas/metabolismo , Donantes de Óxido Nítrico/farmacología , Óxido Nítrico Sintasa de Tipo I/genética
16.
J Mater Sci Mater Med ; 22(7): 1681-7, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21656033

RESUMEN

High corrosion rate and accumulation of hydrogen gas upon degradation impede magnesium alloys' clinical application as implants. In this work, micro-arc oxidation (MAO) was used to fabricate a porous coating on magnesium alloys as an intermediate layer to enhance the bonding strength of propolis layer. Then the composite coatings were fabricated using sol-gel method by dipping sample into the solution containing propolis and polylactic acid at 40 °C. The corrosion resistance of the samples was determined based on potentiodynamic polarization experiments and immersion tests. Biocompatibility was designed by observing the attachment and growth of wharton's jelly-derived mesenchymal stem cells (WJCs) on substrates with MAO coating and substrates with composite coatings. The results showed that, compared with that of Mg-Zn-Ca alloy, the corrosion current density of the samples with composite coatings decreased from 5.37 × 10⁻5 to 1.10 × 10⁻6 A/cm² and the corrosion potential increased by 240 mV. Composite coatings exhibit homogeneous corrosion behavior and can promote WJCs cell adhesion and proliferation. In the meantime, pH value was relatively stable during the immersion tests, which may be significant for cellular survival. In conclusion, our results indicate that composite coatings on Mg-Zn-Ca alloy fabricated by MAO/sol-gel method provide a new type bioactive material.


Asunto(s)
Aleaciones/química , Calcio/química , Magnesio/química , Zinc/química , Materiales Biocompatibles , Técnicas de Cultivo de Célula , Proliferación Celular , Técnicas Electroquímicas , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/fisiología , Microscopía Electrónica de Rastreo , Oxidación-Reducción , Propiedades de Superficie
17.
Auton Neurosci ; 154(1-2): 3-13, 2010 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-19939745

RESUMEN

The lower urinary tract is a muscular system composed of the urinary bladder and the outflow tract. During filling with urine the bladder is relaxed and the outflow tract offers a high resistance; during emptying the outflow resistance falls and the bladder wall generates a high wall tension to raise intravesical pressure. The coordination of these responses is organized in the brainstem and sacral spinal cord to control the activity of autonomic and somatic efferents to the smooth muscle of the bladder (detrusor) and the smooth and skeletal muscle of the bladder base and urethra. Detrusor contraction is predominantly controlled by parasympathetic fibres releasing acetylcholine and ATP; the outflow tract is controlled by parasympathetic and sympathetic fibres to the bladder base (trigone) and urethral smooth muscle (including a nitregic component) and somatic fibres to the urethral rhabdosphincter. The smooth muscles also develop spontaneous contractions that determine the tone of the musculature. The cellular signaling pathways that evoke contraction due to neurotransmitter release and the origin of spontaneous activity are discussed, as well as the electrical properties of the smooth muscle relevant to the propagation of electrical signals. Finally the interaction of muscle cells with other cell types (epithelium and interstitial cells) is considered, relevant to their ability to regulate muscle contractility. Throughout, the basic physiological processes are considered in relation to pathological developments that are prevalent in the human lower urinary tract, in particular the overactive bladder and urinary incontinence, and the identification of drug targets to manage these conditions.


Asunto(s)
Contracción Muscular/fisiología , Músculo Liso/fisiología , Sistema Urinario/citología , Animales , Calcio/metabolismo , Humanos , Músculo Esquelético/fisiología , Músculo Esquelético/fisiopatología , Receptores de Neurotransmisores/metabolismo , Enfermedades Urológicas/patología
18.
Acta Chir Belg ; 109(6): 751-5, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20184061

RESUMEN

OBJECTIVES: Lower urinary tract symptoms (LUTS) are associated with sexual dysfunction; however, these can vary by population. Thus, the prevalence, severity, and predisposing factors for sexual dysfunction in Taiwanese men (> 40 y) who visited a urologic clinic for LUTS was determined. METHODS: During 2005 and 2006, a prospective survey was carried out which included 412 men with LUTS. Demographic data were collected during face-to-face interviews. Sexual dysfunction and LUTS were evaluated using the Danish Prostatic Symptom Score (DAN-PSS) and the International Prostate Symptom Score (IPSS) questionnaire, respectively. RESULTS: Mild, moderate, and severe LUTS were observed in 25.61%, 47.80%, and 26.59% of the patients, respectively. Reduced or absence of erection, reduced or no ejaculation, and pain upon ejaculation were found in 78.29%, 76.59%, and 6.11% of the patients, respectively. However, only 26.9%, 22.1%, and 4.4% of patients with erectile dysfunction (ED), ejaculatory dysfunction, and pain upon ejaculation were bothered by the sexual dysfunction, respectively. Age was significantly associated with ED, ejaculatory dysfunction (EjD), and pain with ejaculation (p < 0.001). The prevalence of sexual dysfunction increased with the severity of LUTS but was not significantly different. Patients with diabetes were 5.96 times more likely to have sexual dysfunction (95% CI = 1.39 to 25.60; p = 0.017). CONCLUSIONS: Over 70% of LUTS patients in this study suffered from sexual dysfunction. Although age and diabetes were associated with sexual dysfunction, LUTS severity was not.


Asunto(s)
Disfunción Eréctil/epidemiología , Hiperplasia Prostática/epidemiología , Trastornos Urinarios/epidemiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Comorbilidad , Diabetes Mellitus/epidemiología , Eyaculación , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Taiwán/epidemiología
19.
Cell Mol Life Sci ; 65(15): 2431-44, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18581053

RESUMEN

Cystine knot toxins (CKTs) in spider venoms represent a rich source of novel ligands for varied ion channels. Here, we identified 95 novel putative CKT precursors by analyzing expressed sequence tags of the tarantula Chilobrachys jingzhao venom gland. Phylogenetics analyses revealed one orphan family and six families with sequence similarity to known toxins. To further investigate the relationships of their structures, functions and evolution, we assayed 10 representative toxins for their effect on ion channels, and performed structure model comparisons, evolution analysis and toxin distribution analysis. This study revealed two major types of CKTs: pore-blocking toxins and gating modifier toxins. A few blockers were observed with relatively high abundance and wide distribution, which may be a category of original toxins that block channels conserved in various preys with relatively high specificity. The gating modifier families contain advanced toxins, usually have many members and interact with diverse regulatory components of channels.


Asunto(s)
Motivos Nodales de Cisteina , Evolución Molecular , Variación Genética , Venenos de Araña/química , Arañas/química , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Ratas , Alineación de Secuencia , Venenos de Araña/farmacología , Homología Estructural de Proteína
20.
Vet Dermatol ; 19(3): 150-5, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18477331

RESUMEN

Canine atopic dermatitis sensu stricto and food-induced allergic dermatitis are common canine skin conditions, which are often considered clinically undistinguishable. Several attempts have been made to describe populations of atopic dogs and determine breed predisposition but the results were often biased by the use of hospital populations as control group. The present study aims to describe a population of Swiss atopic and food-allergic dogs and to compare it with a data set representing more than 85% of all Swiss dogs. The study, which was carried out during 1 year in several practices and teaching hospital in Switzerland, describes a group of 259 allergic dogs, determines breed predisposition for atopic dermatitis and food-induced allergic dermatitis, compares the clinical signs and features of both conditions, and outlines the clinical picture of five frequently affected breeds.


Asunto(s)
Dermatitis Atópica/veterinaria , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/genética , Hipersensibilidad a los Alimentos/veterinaria , Linaje , Animales , Dermatitis Atópica/epidemiología , Dermatitis Atópica/etiología , Dermatitis Atópica/genética , Enfermedades de los Perros/etiología , Perros , Femenino , Hipersensibilidad a los Alimentos/epidemiología , Hipersensibilidad a los Alimentos/etiología , Hipersensibilidad a los Alimentos/genética , Predisposición Genética a la Enfermedad , Masculino , Estudios Prospectivos , Suiza/epidemiología
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