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1.
Sci Total Environ ; 946: 174396, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38950634

RESUMO

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.


Assuntos
Nitrogênio , Raízes de Plantas , Solo , Áreas Alagadas , Nitrogênio/metabolismo , Raízes de Plantas/metabolismo , Solo/química , Poaceae , Exsudatos de Plantas , Desnitrificação
2.
Arch Virol ; 166(8): 2333-2335, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34075444

RESUMO

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.


Assuntos
Vírus de Insetos/classificação , Vespas/virologia , Sequenciamento Completo do Genoma/métodos , Sequência de Aminoácidos , Animais , Tamanho do Genoma , Genoma Viral , Vírus de Insetos/genética , Vírus de Insetos/isolamento & purificação , Fases de Leitura Aberta , Filogenia , Análise de Sequência de RNA
3.
Tob Induc Dis ; 19: 34, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33994906

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-31578652

RESUMO

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.


Assuntos
Esclerose Lateral Amiotrófica/induzido quimicamente , Esclerose Lateral Amiotrófica/epidemiologia , Exposição Ambiental/efeitos adversos , Chumbo/efeitos adversos , Exposição Ocupacional/efeitos adversos , Vigilância da População , Esclerose Lateral Amiotrófica/diagnóstico , Estudos de Casos e Controles , Humanos , Vigilância da População/métodos , Fatores de Risco
5.
Viruses ; 11(3)2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871248

RESUMO

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.


Assuntos
Genoma Viral , Himenópteros/virologia , Filogenia , Vírus de RNA/genética , Animais , Vírus de RNA/classificação , Vírus de RNA/isolamento & purificação , RNA Viral/genética , Proteínas Virais/genética , Sequenciamento Completo do Genoma
6.
J Proteomics ; 192: 37-53, 2019 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-30098407

RESUMO

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.


Assuntos
Venenos de Artrópodes/metabolismo , Besouros/parasitologia , Perfilação da Expressão Gênica , Himenópteros/metabolismo , Proteínas de Insetos/metabolismo , Proteômica , Animais , Pupa/metabolismo , Especificidade da Espécie
7.
Bull Entomol Res ; 109(2): 248-256, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30514411

RESUMO

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.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Besouros/imunologia , Interações Hospedeiro-Parasita , Fagocitose , Vespas/fisiologia , Animais , Besouros/metabolismo , Besouros/parasitologia , Pupa/imunologia , Pupa/metabolismo , Pupa/parasitologia , Venenos de Vespas
8.
J Insect Physiol ; 109: 125-137, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30025717

RESUMO

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.


Assuntos
Besouros/imunologia , Besouros/parasitologia , Vespas/química , Vespas/fisiologia , Animais , Venenos de Artrópodes/toxicidade , Besouros/efeitos dos fármacos , Feminino , Mucinas , Ovário/química , Óvulo
9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-709006

RESUMO

Objective To understand the current status of social support among the elderly,aged ≥60 years,as well as to identify influencing factors and to provide a reference for relevant health care services.Methods Publications about social support of the elderly were collected by searching the database of CNKI,VIP,Wanfang Data,Pubmed,and Web of Science.A random effects model was employed according to the results of heterogeneity (I2>50%) to pool the extracted data.Results Thirty-two articles were included,with a total sample of 21 763 articles.Total scores of social support and three dimensions were low,with social support of 34.047 (95%CI:32.532-35.563),subjective support of 19.218 (95%CI:17.589-20.846),objective support of 7.787 (95%CI:7.483-8.091),and support utilization of 7.075 (95%CI:6.884-7.266).Scores of elderly with character of high age (aged 80:30.907,95%CI:28.378-33.436),female (32.512,95%CI:30.723-34.300),low education (illiteracy:32.088,95%CI:30.944-33.231;primary school:32.709,95%CI:30.069-35.349),country side (33.780,95%CI:31.523-36.038),empty nest (32.301,95%CI:27.061-37.542) and incomplete marriage (discoverture:27.044,95%CI:24.652-29.437;divorced:29.159,95%CI:24.520-33.791) was lower than the others.Conclusions The current status of social support is not optimistic.Scores of social support and its dimensions were relatively low,and a significant difference was found between elderly of different character,indicating that health interventions should be implemented based on character.

11.
Artigo em Inglês | MEDLINE | ID: mdl-27101988

RESUMO

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.


Assuntos
Besouros/imunologia , Besouros/parasitologia , Interações Hospedeiro-Parasita/imunologia , Himenópteros/fisiologia , Pupa/parasitologia , Animais , Besouros/enzimologia , Besouros/metabolismo , Granulócitos/citologia , Granulócitos/imunologia , Hemócitos/citologia , Hemócitos/imunologia , Melaninas/metabolismo , Monofenol Mono-Oxigenase/metabolismo
12.
Lab Chip ; 14(17): 3233-40, 2014 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-24903337

RESUMO

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.


Assuntos
Equipamentos e Provisões , Humanos
13.
PLoS One ; 9(3): e91482, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24614330

RESUMO

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.


Assuntos
Besouros/genética , Besouros/imunologia , Perfilação da Expressão Gênica , Himenópteros/fisiologia , Espécies Introduzidas , Animais , Análise por Conglomerados , Besouros/parasitologia , Ontologia Genética , Genes de Insetos , Interações Hospedeiro-Parasita/genética , Anotação de Sequência Molecular , Pupa/genética , Pupa/parasitologia , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Especificidade da Espécie , Transcrição Gênica
14.
Inflamm Bowel Dis ; 19(8): 1671-80, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23749272

RESUMO

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.


Assuntos
Autoanticorpos/sangue , Biomarcadores/sangue , Constrição Patológica/diagnóstico , Doença de Crohn/diagnóstico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Obstrução Intestinal/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/imunologia , Criança , Pré-Escolar , Estudos de Coortes , Constrição Patológica/sangue , Constrição Patológica/etiologia , Doença de Crohn/sangue , Doença de Crohn/complicações , Feminino , Seguimentos , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Humanos , Lactente , Recém-Nascido , Obstrução Intestinal/sangue , Obstrução Intestinal/etiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Adulto Jovem
15.
J Neural Eng ; 10(4): 045002, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23723130

RESUMO

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.


Assuntos
Potenciais de Ação/fisiologia , Córtex Cerebral/fisiologia , Materiais Revestidos Biocompatíveis/química , Eletrodos Implantados , Eletroencefalografia/instrumentação , Monitorização Ambulatorial/instrumentação , Polímeros/química , Xilenos/química , Animais , Materiais Revestidos Biocompatíveis/farmacologia , Condutividade Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Masculino , Ratos , Ratos Sprague-Dawley
16.
Neurourol Urodyn ; 31(4): 572-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22275213

RESUMO

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.


Assuntos
Músculo Liso/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico/metabolismo , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Sinalização do Cálcio/efeitos dos fármacos , Feminino , Hidrazinas/farmacologia , Masculino , Camundongos , Camundongos Knockout , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Neurônios/metabolismo , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase Tipo I/genética
17.
J Mater Sci Mater Med ; 22(7): 1681-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21656033

RESUMO

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.


Assuntos
Ligas/química , Cálcio/química , Magnésio/química , Zinco/química , Materiais Biocompatíveis , Técnicas de Cultura de Células , Proliferação de Células , Técnicas Eletroquímicas , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Microscopia Eletrônica de Varredura , Oxirredução , Propriedades de Superfície
18.
Auton Neurosci ; 154(1-2): 3-13, 2010 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-19939745

RESUMO

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.


Assuntos
Contração Muscular/fisiologia , Músculo Liso/fisiologia , Sistema Urinário/citologia , Animais , Cálcio/metabolismo , Humanos , Músculo Esquelético/fisiologia , Músculo Esquelético/fisiopatologia , Receptores de Neurotransmissores/metabolismo , Doenças Urológicas/patologia
19.
Acta Chir Belg ; 109(6): 751-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20184061

RESUMO

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.


Assuntos
Disfunção Erétil/epidemiologia , Hiperplasia Prostática/epidemiologia , Transtornos Urinários/epidemiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Diabetes Mellitus/epidemiologia , Ejaculação , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Índice de Gravidade de Doença , Inquéritos e Questionários , Taiwan/epidemiologia
20.
Cell Mol Life Sci ; 65(15): 2431-44, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18581053

RESUMO

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.


Assuntos
Motivos Nó de Cisteína , Evolução Molecular , Variação Genética , Venenos de Aranha/química , Aranhas/química , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Alinhamento de Sequência , Venenos de Aranha/farmacologia , Homologia Estrutural de Proteína
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