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1.
Artigo em Chinês | MEDLINE | ID: mdl-34365757

RESUMO

Objective: To analyse the dose-response relationships between the kurtosis metric of noise and noise-induced hearing loss (NIHL) and study the role of kurtosis in the evaluation of NIHL associated with non-Gaussian noise. Methods: From January 2012 to December 2017, a total of 1869 workers in seven manufacturing industries were selected as the study subjects. The basic data of the workers were investigated by questionnaire, personal noise waveform was collected for a long time, and pure tone hearing threshold was tested. The 8-hour continuous equivalent A sound level (L(Aeq, 8 h)) , cumulative noise exposure (CNE) and kurtosis structure indexes were calculated. The dose-response relationships between kurtosis and NIHL were analyzed by stratification analysis method, which controlled the influence of CNE, L(Aeq, 8 h), exposure duration, age and sex on hearing loss using high-frequency noise-induced permanent threshold shift (NIPTS(346)) and high-frequency noise-induced hearing loss (HFNIHL) as outcome indicators. Results: When CNE was <90 dB (A) ·year and ≥100 dB (A) ·year, NIPTS(346) in the extremely high kurtosis group was significantly greater than that in the Gaussian kurtosis, low kurtosis and medium kurtosis group (P<0.05) . In the workers exposed to L(Aeq, 8 h)<85 dB (A) and ≥94 dB (A) , NIPTS(346) in the extremely high kurtosis group was significantly greater than that in the Gaussian kurtosis group (P<0.05) . Among workers under the age of 50 or male workers, NIPTS(346) in the extremely high kurtosis group was significantly greater than that in the Gaussian kurtosis, low kurtosis and medium kurtosis group (P<0.05) . Kurtosis was positively correlated with NIPTS(346) (r=0.121, P<0.05) . When CNE was <100 dB (A) ·year, the detection rate of HFNIHL increased with the increase of kurtosis level (P<0.01) . Logistic regression analysis showed that kurtosis was an important influencing factor for HFNIHL (OR=1.321) . Conclusion: Kurtosis has a dose-response relationship with the detection rate of HFNIHL in noise exposed workers, and noise kurtosis is an influencing factor of NIHL.


Assuntos
Perda Auditiva Provocada por Ruído , Ruído Ocupacional , Exposição Ocupacional , Audição , Perda Auditiva Provocada por Ruído/etiologia , Humanos , Masculino , Indústria Manufatureira , Ruído Ocupacional/efeitos adversos , Exposição Ocupacional/efeitos adversos , Inquéritos e Questionários
2.
Int Endod J ; 54(4): 536-555, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33159322

RESUMO

BACKGROUND: Regenerative techniques are increasingly applied in endodontic surgery, but different materials used in regenerative techniques may have varying impacts on wound healing. OBJECTIVES: This study evaluated the effects of different regenerative techniques and materials on the outcome of endodontic surgery. PARTICIPANTS: patients with persistent periapical lesions, treated with root-end surgery. CONTROL: endodontic surgery without the use of regenerative techniques/materials. INTERVENTION: endodontic surgery with the use of regenerative techniques/materials. OUTCOME: combined clinical and radiographic results. METHODS: PubMed, Web of Science, Embase, SinoMed and the CENTRAL Cochrane were searched up to 10th July 2020, followed by a manual search. Detailed eligibility criteria were applied. Cochrane's risk-of-bias tool 2.0 was used to assess the risk of bias of the eligible studies. Meta-analysis was conducted using RevMan software. Subgroup analyses were performed based on the regenerative materials used in endodontic surgery. RESULTS: Eleven eligible randomized controlled trials (RCTs) were included in the meta-analysis: two had a low risk of overall bias, and nine had some concerns of overall bias. Generally, the use of regenerative techniques significantly improved the outcome of endodontic surgery (risk ratio [RR]: 0.42; 95% confidence interval [CI], 0.26-0.68; P < 0.001). On subgroup analysis, the use of expanded polytetrafluoroethylene (e-PTFE) membranes alone had no added benefits (RR: 2.00; 95% CI, 0.22-18.33; P = 0.54). The application of collagen membranes or autologous platelet concentrates (APCs) alone was associated with a trend for better outcomes (RR: 0.51; 95% CI, 0.20-1.25; P = 0.14) (RR: 0.55; 95% CI, 0.18-1.71; P = 0.30). The combined use of collagen membranes and bovine-derived hydroxyapatite significantly improved the outcome (RR: 0.35; 95% CI, 0.17-0.75; P = 0.007). DISCUSSION: This systematic review evaluated the effects of collagen membranes, e-PTFE membranes, APCs and bone grafting materials, providing detailed information about the risks and benefits of using each regenerative technique/material or its combination in endodontic surgery. CONCLUSIONS: Regenerative techniques improve periapical lesion healing after endodontic surgery. The combined use of collagen membranes and bovine-derived hydroxyapatite may be beneficial as an adjunct to endodontic surgery. In contrast, the positive efficacy of e-PTFE membranes or APCs alone remains doubtful.


Assuntos
Colágeno , Cicatrização , Animais , Bovinos , Humanos
3.
Zhonghua Gan Zang Bing Za Zhi ; 24(7): 486-492, 2016 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-27784425

RESUMO

Objective: To investigate the risk factors for early rebleeding after esophageal variceal ligation (EVL) through a multicenter retrospective study. Methods: A total of 3289 patients who were hospitalized and underwent EVL in 17 upper second-class hospitals or hospitals of higher classes from January 1999 to May 2015 were collected and screened according to the exclusion criteria. A total of 2531 patients were screened out, and a retrospective analysis was performed for their clinical data including age, sex, endoscopic findings, and results of laboratory examination (liver function, biochemical results, routine blood test, and coagulation function) to collect related data. According to the presence or absence of rebleeding within 1 month after EVL, the patients were divided into rebleeding group and non-rebleeding group. SPSS22.0 software was used for independent t-test and one-way analysis of variance, and P < 0.05 was considered statistically significant. Results: In the 2531 patients who underwent EVL, the rate of early rebleeding after EVL was 6.6%, and the mortality rate was 12.0%. The results showed that sex (P = 0.014), number of veins with varices (P = 0.203), prothrombin time (P = 0.001), prothrombin activity (P = 0.014), albumin (P = 0), total bilirubin (P = 0.011), aspartate aminotransferase (P = 0.004), white blood cell count (P = 0.342), hepatic encephalopathy (P = 0.021), ascites (P = 0.027), Child-Pugh class (P = 0), Child-Pugh score (P = 0), glue injection for gastric varices (P = 0.521), gastric varices (P = 0.32), shunt (P = 0.174), number of ligation points (P = 0.001), number of ligation times (P = 0.024), number of times of hematemesis before treatment (P = 0), number of times of tarry stool (P = 0.008), and volume of blood in hematemesis before treatment (P = 0) were risk factors for early rebleeding after EVL. The regression analysis showed that male sex, a Child-Pugh score of >7.2, and volume of blood in hematemesis before treatment were independent risk factors for early rebleeding after EVL, while an albumin concentration of > 31.5 g/L was the protective factor. Conclusion: EVL has a good therapeutic effect in esophageal variceal rebleeding. Among all the factors analyzed, male sex, a Child-Pugh score of > 7.2, and volume of blood in hematemesis before treatment are independent risk factors for early rebleeding after EVL, and an albumin concentration of > 31.5 g/L is a protective factor.


Assuntos
Varizes Esofágicas e Gástricas/cirurgia , Hemorragia Gastrointestinal/diagnóstico , Cirrose Hepática/complicações , Humanos , Ligadura , Masculino , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica/química
4.
Plant Dis ; 99(3): 416, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30699721

RESUMO

Clausena lansium, also known as wampee (Clausena wampi), is a plant species native to China, Vietnam, the Philippines, Malaysia, and Indonesia, where it is widely cultivated, and also grown in India, Sri Lanka, Queensland, Florida, and Hawaii, but less frequently (3). The fruit can be consumed fresh or made into juice, jam, or succade. In summer to fall 2014, a soft rot disease was found in a wampee planting region in Yunan County, Guangdong Province, China. On Sept. 18, we collected diseased samples from a wampee orchard with about 20% disease incidence. The infected fruit initially showed pinpoint spots on the peel, water-soaked lesions, and light to dark brown discoloration. Spots expanded in 2 days, and tissues collapsed after 5 days. Severely affected fruit showed cracking or nonodorous decay. Five diseased samples were collected, and causal agents were isolated from symptomatic tissues 1 cm under the peel after surface sterilization in 0.3% NaOCl for 10 min and rinsing in sterile water three times. Tissues were placed on a Luria Bertani (LB) plate for culture. Ten representative isolates were selected for further characterization. No colony was isolated from healthy tissues. Colonies were round, smooth, with irregular edges, and produced a yellow pigment in culture. Biolog identification (Version 4.20.05) showed that all strains were gram negative, negative for indole production, and utilized glucose, maltose, trehalose, sucrose, D-lactose, and pectin but not sorbitol or gelatin. The isolates were identified as Pantoea agglomerans (SIM 0.69). Multilocus sequence analysis (MLSA) was conducted for rapid classification of the strains. Sequences of atpD, gyrB, infB, and rpoB were amplified using corresponding primers (2). All sequences of the 10 isolates were identical in each gene. BLASTn was performed, and maximum likelihood trees based on the concatenated nucleotide sequences of the four genes were constructed using MEGA6. Bootstrap values after 1,000 replicates were expressed as percentages. Results showed that the tested strain named CL1 was most homologous to P. anthophila, with 98% identity for atpD (KM521543), 100% for gyrB (KM521544), infB (KM521545), and rpoB (KM521546). The 16S rRNA sequence (KM521542) amplified by primers 27f and 1492r shared 99% identity with that of P. anthophila M19_2C (JN644500). P. anthophila was previously reclassified from P. agglomerans (3); therefore, we suggest naming this wampee pathogen P. anthophila. Subsequently, 10 wampee fruits were injected with 20 µl of bacterial suspension (1 × 108 CFU/ml) of strains CL1 and CL2, respectively, and another 10 were injected with 20 µl of LB medium as controls, all kept at 28°C for 4 days. Symptoms similar to those of natural infections were observed on inoculated fruits but not on the negative controls. Bacteria were isolated from diseased tissues and further identified as P. anthophila by gyrB sequencing. P. anthophila was reported to naturally infect balsam and marigold (1,2). To our knowledge, this is the first report of P. anthophila naturally causing soft rot disease and cracking on C. lansium (wampee). References: (1) C. Brady et al. Syst. Appl. Microbiol. 31:447, 2008. (2) C. Brady et al. Int. J. Syst. Evol. Microbiol. 59:2339, 2009. (3) J. Morton. Fruits of Warm Climates. Echo Point Books & Media, Miami, FL, 1987.

5.
Neuroscience ; 265: 124-36, 2014 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-24486962

RESUMO

Vasopressin (VP), oxytocin (OXT) and vasoactive intestinal polypeptide (VIP) in the brain modulate physiological and behavioral processes in many vertebrates. Day-active tree shrews, the closest relatives of primates, live singly or in pairs in territories that they defend vigorously against intruding conspecifics. However, anatomy concerning peptidergic neuron distribution in the tree shrew brain is less clear. Here, we examined the distribution of VP, OXT and VIP immunoreactivity in the hypothalamus and extrahypothalamic regions of tree shrews (Tupaia belangeri chinensis) using the immunohistochemical techniques. Most of VP and OXT immunoreactive (-ir) neurons were found in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) of the hypothalamus. In addition, VP-ir or OXT-ir neurons were scattered in the preoptic area, anterior hypothalamic areas, dorsomedial hypothalamic nucleus, stria terminalis, bed nucleus of the stria terminalis and medial amygdala. Interestingly, a high density of VP-ir fibers within the ventral lateral septum was observed in males but not in females. Both VP-ir and VIP-ir neurons were found in different subdivisions of the suprachiasmatic nucleus (SCN) with partial overlap. VIP-ir cells and fibers were also scattered in the cerebral cortex, anterior olfactory nucleus, amygdala and dentate gyrus of the hippocampus. These findings provide a comprehensive description of VIP and a detailed mapping of VP and OXT in the hypothalamus and extrahypothalamic regions of tree shrews, which is an anatomical basis for the participation of these neuropeptides in the regulation of circadian behavior and social behavior.


Assuntos
Hipotálamo/química , Ocitocina/análise , Peptídeo Intestinal Vasoativo/análise , Vasopressinas/análise , Animais , Química Encefálica , Feminino , Masculino , Tupaiidae
6.
Transl Psychiatry ; 3: e336, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24346134

RESUMO

Clinical reports have highlighted a role for retinoids in the etiology of mood disorders. Although we had shown that recruitment of the nuclear receptor retinoic acid receptor-α (RAR-α) to corticotropin-releasing hormone (CRH) promoter is implicated in activation of the hypothalamus-pituitary-adrenal (HPA) axis, further insight into how retinoids modulate HPA axis activity is lacking. Here we show that all-trans retinoic acid (RA)-induced HPA activation involves impairments in glucocorticoid receptor (GR) negative feedback. RA was applied to rats chronically through intracerebroventricular injection. A 19-day RA exposure induced potent HPA axis activation and typical depression-like behavior. Dexamethasone failed to suppress basal corticosterone (CORT) secretion, which is indicative of a disturbed GR negative feedback. In the hypothalamic paraventricular nucleus, increased CRH⁺ and c-fos⁺ cells were found while a negative R-2⁺/ER⁺ correlation was present between the number of RAR-α⁺ and GR⁺ cells. This was paralleled by increased RAR-α and decreased GR protein expression in the hypothalamus. Additional in vitro studies confirmed that RA abolished GR-mediated glucocorticoid-induced suppression of CRH expression, indicating a negative cross-talk between RAR-α and GR signaling pathways. Finally, the above changes could be rapidly normalized by treatment with GR antagonist mifepristone. We conclude that in addition to the 'classic' RAR-α-mediated transcriptional control of CRH expression, disturbances in GR negative feedback constitute a novel pathway that underlies RA-induced HPA axis hyperactivity. The rapid normalization by mifepristone may be of potential clinical interest in this respect.


Assuntos
Comportamento Animal/efeitos dos fármacos , Corticosterona/metabolismo , Depressão/metabolismo , Retroalimentação Fisiológica/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Receptores de Glucocorticoides/efeitos dos fármacos , Tretinoína/farmacologia , Animais , Hormônio Liberador da Corticotropina/efeitos dos fármacos , Hormônio Liberador da Corticotropina/metabolismo , Depressão/induzido quimicamente , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Antagonistas de Hormônios/farmacologia , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Mifepristona/farmacologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Receptores de Glucocorticoides/antagonistas & inibidores , Receptores de Glucocorticoides/metabolismo , Receptores do Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico , Transdução de Sinais , Tretinoína/efeitos adversos
7.
Genet Mol Res ; 12(4): 5704-13, 2013 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-24301939

RESUMO

Agropyron Gaertn. is the most important genus in Triticeae (Poaceae), which includes many forage grasses with high economic value. The genetic diversity and relationships of 36 accessions from five crested wheatgrass species were analyzed by gliadin markers. A total of 54 product bands were detected after acid polyacrylamide gel electrophoresis (A-PAGE), of which 100% were polymorphic. The genetic similarity coefficient based on Nei-Li's method ranged from 0.065 to 0.755 with an average of 0.451. The Shannon diversity information index showed that there was a high level of genetic diversity among the accessions. An unweighted pair group method with arithmetic average (UPGMA) dendrogram was constructed based on the Nei-Li's genetic similarity coefficients, which showed the phylogenetic relationships among accessions of different species. Analysis of molecular variance (AMOVA) showed that the proportion of variance explained by inter- and intraspecific variance was 9.34 and 90.66%, respectively, which revealed that the genetic variations within species were higher than the variations among species. Based on pairwise genetic distances (ΦST) among species, the cluster analysis indicated that A. mongolicum had a low-affinity relationship with other species, while A. fragile showed a close relationship with A. cristatum ssp pectinatum. Finally, the implications of the results for the taxonomy of Agropyron were discussed.


Assuntos
Agropyron/genética , Variação Genética , Gliadina/genética , Agropyron/classificação , Filogenia
8.
Endocrinology ; 153(7): 3337-44, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22562172

RESUMO

Estrogen plays an important role in the regulation of the hypothalamus-pituitary-adrenal (HPA)-axis, but the neuroendocrine pathways and the role of estrogen receptor (ER) subtypes involved in specific aspects of this interaction remain unknown. In a first set of experiments, we administered estradiol (E2) intravenously, intracerebroventricularly, and by intrahypothalamic microdialysis to ovariectomized rats to measure plasma corticosterone (CORT) concentrations from carotid artery blood. Systemic infusion of E2 did not increase plasma CORT, but intracerebroventricular E2 induced a 3-fold CORT increase (P = 0.012). Local E2 infusions in the hypothalamic paraventricular nucleus (PVN) significantly increased plasma CORT (P < 0.001). A similar CORT increase was seen after PVN infusion of the ERα agonist propylpyrazoletriol, whereas the ERß agonist diarylpropiolnitrile had no effect. In a second set of experiments, we investigated whether E2 modulates the HPA-axis response to acute stress by administering E2 agonists or its antagonist ICI 182,780 into the PVN during restraint stress exposure. After 30 min of stress exposure, plasma CORT had increased 5.0-fold (P < 0.001). E2 and propylpyrazoletriol administration in the PVN enhanced the stress-induced plasma CORT increase (8-fold vs. baseline), whereas ICI 182,780 and diarylpropiolnitrile reduced it, as compared with both E2 and vehicle administration in the PVN. In conclusion, central E2 modulates HPA-axis activity both in the basal state and during restraint stress. In the basal condition, the stimulation is mediated by ERα-sensitive neurons, whereas during stress, it is mediated by both ERα and ERß.


Assuntos
Estradiol/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Hipotálamo/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Animais , Corticosterona/farmacologia , Estradiol/análogos & derivados , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Feminino , Fulvestranto , Núcleo Hipotalâmico Paraventricular/metabolismo , Fenóis , Pirazóis/farmacologia , Ratos , Ratos Wistar , Fatores de Tempo
9.
Curr Mol Med ; 12(2): 138-52, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22280354

RESUMO

Intraneuronal accumulation of abnormal phosphorylated tau (p-tau) is a molecular pathology in many neurodegenerative tauopathies, including Alzheimer's disease (AD) and frontotemporal dementia with parkinsonism-linked to chromosome 17 (FTDP-17). However, the underlying mechanism remains unclear. Here, we showed an inverse relationship between endoplasmic reticulum membrane ubiquitin ligase (E3) Hrd1 expression and p-tau accumulation in the hippocampal neurons of AD, and proposed that Hrd1 may be a negative regulator of p-tau. This notion was further supported by in vitro study demonstrating that Hrd1 interacted with tau and promoted the degradation of total tau and p-tau as well. The degradation of tau depended on its Hrd1 E3 activity. Knockdown of endogenous Hrd1 with siRNA stabilized tau levels. In addition, inhibition of proteasome maintained tau level and increased Hrd1-mediated tau ubiquitination, suggesting the proteasome was involved in tau/p-tau degradation. Over-expression of Hrd1 significantly alleviated tau cytotoxicity and promoted cell survival. These results indicated that Hrd1 functions as an E3 targeting tau or abnormal p-tau for proteasome degradation. The study provides an important insight into the molecular mechanisms of human tauopathies.


Assuntos
Neurônios/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas tau/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Linhagem Celular , Sobrevivência Celular/genética , Hipocampo/metabolismo , Hipocampo/patologia , Humanos , Fosforilação , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Ubiquitina-Proteína Ligases/genética , Proteínas tau/genética
10.
Exp Clin Endocrinol Diabetes ; 120(4): 217-23, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22187293

RESUMO

AIMS: Epidemiologic studies have examined the possible associations between diabetes mellitus (DM) and gastric cancer (GC), but the results are inconclusive. We conducted a meta-analysis to assess the evidence regarding the associations between diabetes and incidences of, or mortality from, gastric cancer. METHODS: PubMed, Embase and Web of Science were searched up to Oct 20, 2011. We identified studies that included effects estimates with 95% confidence intervals (CIs) of the associations between GC and diabetes. Summary RRs for the GC incidence and mortality were calculated using random-effects model; subgroup analyses were also performed. Heterogeneity among studies was examined using Q and I2 statistics. RESULTS: A total of 7 case-control and 18 cohort studies met the inclusion criteria. The summary RR showed a slightly statistical link between history of DM and GC incidence (RR=1.11, 95% CI: 1.00-1.24, p=0.045, I2=79.5%). In the subgroup analyses, a positive association was noted among the studies conducted in Asia (summary RR=1.19, 95% CI: 1.07-1.32, I2=29.8%). Additionally, slight associations between DM and GC were observed by pooling the data of type 2 DM, cohort studies and the studies controlling more confounders, respectively. Furthermore, mortality from GC with diabetes was increased compared with individuals without diabetes (summary RR=1.29, 95% CI: 1.04-1.59). No publication bias was found. CONCLUSION: Individuals with diabetes have an increased risk of developing gastric cancer, and are positively associated with gastric cancer mortality. Large better-designed cohort studies are needed to verify this conclusion.


Assuntos
Diabetes Mellitus/epidemiologia , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/mortalidade , Viés , Estudos de Casos e Controles , Estudos de Coortes , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/mortalidade , Diabetes Mellitus/mortalidade , Humanos , Incidência , Análise de Sobrevida
11.
Plant Dis ; 96(3): 452, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30727110

RESUMO

Philodendron is a popular foliage plant cultivated in interiorscapes of homes, offices, and malls throughout China. A severe outbreak of a soft rot of Philodendron 'Con-go' occurred in Guangzhou, China from 2010 to 2011. The disease was characterized by leaf infections starting as pinpoint spots that are water soaked and yellow to pale brown. The lesions are sometimes surrounded by a diffuse yellow halo. When the humidity is high and temperatures are warm to hot, the spots expand rapidly, becoming slimy, irregular, and sunken with light tan centers, darker brown borders, and diffused yellow margins and may involve the entire leaf in a few days. An invasion of the midrib and larger veins by the causal bacterium often results in advancement into the petiole and stem. A survey of three areas of production of Philodendron 'Con-go' (5 ha) in Guangzhou revealed that 91% of the fields were affected at an incidence ranging from 15 to 30%. Of 41 bacterial isolates obtained from lesions, three were selected randomly for further characterization. All strains were gram negative, negative for oxidase and positive for catalase and tryptophanase (indole production), and utilized citrate, tartrate, malonate, glucose, sucrose, fructose, and maltose but not glucopyranoside, trehalose, or palatinose. Biolog analysis (version 4.20.05, Hayward, CA) identified the isolates as Pectobacterium chrysanthemi (SIM 0.804 to 0.914). According to Samson et al. (1), it was renamed as a Dickeya sp. PCR was performed on the 16S rDNA gene with primers 27f and 1495r (3) and 1,423 bp of the 16S rDNA gene (GenBank No. JN709491) showed 99% identity to P. chrysanthemi (GenBank No. AF373202), and 98% to Dickeya dieffenbachiae (GenBank No. JF311644). Additionally, the gyrB gene was amplified with primers gyrB-f1 (5'-atgtcgaattcttatgactcctc-3') and gyrB-r1 (5'-tcaratatcratattcgcygctttc-3') designed based on all the submitted gyrB gene sequences of Dickeya spp. The dnaX gene was amplified with primers dnaXf and dnaXr (2). The products were sequenced and phylogeny analyses were performed by means of MEGA 5.05. Results showed that the gyrB and the dnaX genes of the strains were 98% homologous to those of D. dieffenbachiae (GenBank Nos. JF311652 and GQ904757). Therefore, on the basis of phylogenetic trees of the 16S rDNA, gyrB, and dnaX gene sequences, the bacterial isolate named PC1 is related to D. dieffenbachiae (100% bootstrap values). Pathogenicity of each of the three strains on Philodendron 'Con-go' was confirmed by injecting 60 50-day-old seedlings each with 0.1 ml of the isolate suspension (108 CFU/ml) into the leaves. Another 60 were injected with sterile water to serve as the control treatment. Plants were enclosed in plastic bags and returned to the greenhouse under 50% shade at 32°C day and 28°C night temperatures with high humidity. After 72 h, all the injected plants started to show symptoms similar to those observed on field plants, but no symptoms appeared on the control plants. The reisolates were identical to the inoculated strains in biochemical characteristics. Bacteria characteristic of the inoculated strains were not reisolated from the control plants. To our knowledge, this is the first report of D. dieffenbachiae causing soft rot of Philodendron 'Con-go' in China. References: (1) R. Samson et al. Evol. Microbiol. 55:1415, 2005. (2) M. Slawiak et al. Eur. J. Plant Pathol. 125:245, 2009. (3) W. G. Weisbury et al. J. Bacteriol. 173:697, 1991.

12.
Plant Dis ; 96(12): 1818, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30727269

RESUMO

A bacterial disease of rice, bacterial foot rot, was found in Guangdong Province, China in September 2011, with an incidence about 10%. The typical symptom was a dark brown decay of the tillers. In the early stages of the disease, a brown sheath rot seemed to spread from the ligulae regions. The lesions quickly extended down to the nodes, culms, and finally to the crowns. Neighboring tillers of the same crown were invaded systemically, causing foot rot symptoms. A soft rot with an unpleasant odor developed in young tissues of infected tillers. In the advanced stage, many tillers decayed, so that entire diseased plants could easily be pulled from the soil. Six diseased samples were collected and bacteria were isolated from the edge of symptomatic tissues, after samples were sterilized in 0.3% NaOCl for 10 min, rinsed in sterile water three times, and placed on nutrient agar (beef extract 3 g, yeast extract 1 g, peptone 5 g, glucose 10 g, agar 16 g, distilled water 1 L, pH 6.8 to 7.0). For identification, a total of 12 representative isolates were selected. All strains were Gram negative, grew at 37°C, were positive for indole production, and utilized malonate, glucose, and sucrose, but not glucopyranoside, trehalose, or palatinose. Biolog identification (Version 4.20.05, Hayward, CA) identified isolate EC1 as Pectobacterium chrysanthemi (SIM 0.827), which has since been transferred to genus Dickeya. PCR was used to amplify the 16S rDNA gene with primers 27f and 1492r, the dnaX gene with primers dnaXf and dnaXr (2), and the gyrB gene with primers gyrBf1 (5'-ATGTCGAATTCTTATGACTCCTC-3') and gyrB-r1 (5'-TCARATATCRATATTCGCYGCTTTC-3'), which were designed based on published gyrB gene sequences of genus Dickeya. A BLASTn search of all three loci [16S rDNA (JQ284040), dnaX (JQ284041), and gyrB (JQ284042)] revealed that EC1 had 100% sequence identify to Dickeya zeae [16S rDNA (AB713560), dnaX (AB713593), gyrB (AB713635)]. Pathogenicity tests were conducted by injecting 10 rice seedlings with 100 µl of the bacterial suspension (1 × 108 CFU/ml) in the stem base, and an additional 10 rice seedlings were injected with 100 µl of sterile water as negative controls. Inoculations were carried out in a greenhouse at 28 to 32°C and 90% relative humidity. Foot rot symptoms identical to those described above were observed after 7 days on inoculated plants, but not on the negative controls. The bacterium was reisolated from the lesions and had 100% sequence identity for all three loci to EC1. Previously, similar symptoms were reported on rice in Guangdong province of China, and the causal agent was identified as Erwinia chrysanthemi (1). To our knowledge, this is the first report of D. zeae causing foot rot disease on rice in China. References: (1) Q. G. Liu et al. J. South China Agric. Univ. 18:128, 1997. (2) M. Slawiak et al. Eur. J. Plant Pathol. 125:245, 2009.

13.
Plant Dis ; 96(5): 760, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-30727539

RESUMO

Phalaenopsis orchids, originally from tropical Asia, are mainly planted in Thailand, Singapore, Malaysia, the Philippines, and Taiwan and have gained popularity from consumers all over the world. The cultivation area of Phalaenopsis orchids has been rising and large-scale bases have been established in mainland China, especially South China because of suitable environmental conditions. In September 2011, a soft rot of Phalaenopsis aphrodita was found in a Phalaenopsis planting base in Guangzhou with an incidence of ~15%. Infected plants initially showed water-soaked, pale-to-dark brown pinpoint spots on leaves that were sometimes surrounded by a yellow halo. Spots expanded rapidly with rising humidity and temperatures, and in a few days, severely extended over the blade with a light tan color and darker brown border. Lesions decayed with odorous fumes and tissues collapsed with inclusions exuding. The bacterium advanced to the stem and pedicle. Finally, leaves became papery dry and the pedicles lodged. Six diseased samples were collected, and bacteria were isolated from the edge of symptomatic tissues after sterilization in 0.3% NaOCl for 10 min, rinsing in sterile water three times, and placing on nutrient agar for culture. Twelve representative isolates were selected for further characterization. All strains were gram negative, grew at 37°C, were positive for indole production, and utilized malonate, glucose, and sucrose but not glucopyranoside, trehalose, or palatinose. Biolog identification (version 4.20.05, Hayward, CA) was performed and Pectobacterium chrysanthemi (SIM 0.868) was confirmed for the tested isolates (transfer to genus Dickeya). PCR was used to amplify the 16S rDNAgene with primers 27f and 1492r, dnaX gene with primers dnaXf and dnaXr (3), and gyrB gene with primers gyrBf (5'-GAAGGYAAAVTKCATCGTCAGG-3') and gyrB-r1 (5'-TCARATATCRATATTCGCYGCTTTC-3') designed on the basis of the published gyrB gene sequences of genus Dickeya. BLASTn was performed online, and phylogeny trees (100% bootstrap values) were created by means of MEGA 5.05 for these gene sequences, respectively. Results commonly showed that the representative tested strain, PA1, was most homologous to Dickeya dieffenbachiae with 98% identity for 16S rDNA(JN940859), 97% for dnaX (JN989971), and 96% for gyrB (JN971031). Thus, we recommend calling this isolate D. dieffenbachiae PA1. Pathogenicity tests were conducted by injecting 10 P. aphrodita seedlings with 100 µl of the bacterial suspension (1 × 108 CFU/ml) and another 10 were injected with 100 µl of sterile water as controls. Plants were inoculated in a greenhouse at 28 to 32°C and 90% relative humidity. Soft rot symptoms were observed after 2 days on the inoculated plants, but not on the control ones. The bacterium was isolated from the lesions and demonstrated identity to the inoculated plant by the 16S rDNA sequence comparison. Previously, similar diseases of P. amabilis were reported in Tangshan, Jiangsu, Zhejiang, and Wuhan and causal agents were identified as Erwinia spp. (2), Pseudomonas grimontii (1), E. chrysanthemi, and E. carotovora subsp. carovora (4). To our knowledge, this is the first report of D. dieffenbachiae causing soft rot disease on P. aphrodita in China. References: (1) X. L. Chu and B. Yang. Acta Phytopathol. Sin. 40:90, 2010. (2) Y. M. Li et al. J. Beijing Agric. Coll. 19:41, 2004. (3) M. Slawiak et al. Eur. J. Plant Pathol. 125:245, 2009. (4) Z. Y. Wu et al. J. Zhejiang For. Coll. 27:635, 2010.

14.
J Neuroendocrinol ; 23(5): 435-43, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21392135

RESUMO

Activation of the hypothalamic-pituitary-adrenal axis is considered to be one of the key physiological responses to stress and, interestingly, shows a marked sex difference. Oestradiol plays an important role in this sex difference. The present study investigated the systemic and intrahypothalamic oestradiol response to physical restraint stress in female rats. We used jugular catheterisation and intrahypothalamic microdialysis to simultaneously measure plasma oestradiol and local oestradiol concentrations in the paraventricular nucleus (PVN) of the hypothalamus. We also assessed corticotrophin-releasing hormone (CRH), aromatase, and oestrogen receptor (ER) α and ß mRNA expression in the PVN by quantitative polymerase chain reaction immediately after the acute stress period. As expected, PVN CRH mRNA and plasma corticosterone were significantly increased after acute stress. Interestingly, the local oestradiol concentration in the PVN also increased during the 1-h stress period in pro-oestrus and in ovariectomised (OVX) animals. Aromatase mRNA expression in the PVN was increased markedly in pro-oestrus but only modestly in oestrus. PVN ERß but not ERα mRNA expression was significantly elevated in pro-oestrous animals. In addition, plasma oestradiol levels increased 10 min after stress, both during pro-oestrus and oestrus but not in OVX animals. To conclude, we report an intra-hypothalamic oestradiol response to restraint stress. The rising hypothalamic oestradiol concentration together with increased ERß gene expression indicates a positive feedback of hypothalamic oestradiol signalling during acute stress in rats.


Assuntos
Aromatase/genética , Estradiol/metabolismo , Receptor beta de Estrogênio/metabolismo , Hipotálamo/metabolismo , RNA Mensageiro/metabolismo , Restrição Física/psicologia , Estresse Fisiológico/fisiologia , Animais , Aromatase/metabolismo , Corticosterona/sangue , Hormônio Liberador da Corticotropina/genética , Hormônio Liberador da Corticotropina/metabolismo , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/fisiologia , Hipotálamo/anatomia & histologia , Microdiálise , Sistema Hipófise-Suprarrenal/fisiologia , Ratos , Ratos Sprague-Dawley
15.
Neuroscience ; 174: 132-42, 2011 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-21130848

RESUMO

Retinoids, a family of molecules that is derived from vitamin A, are involved in a complex signaling pathway that regulates gene expression and controls neuronal differentiation in the central nervous system. The physiological actions of retinoids are mainly mediated by retinoic acid receptors. Here we describe the distribution of retinoic acid receptor α (RARα) in the human hypothalamus by immunohistochemistry. RARα immunoreactivity showed a widespread pattern throughout the hypothalamus, with high density in the suprachiasmatic nucleus (SCN), paraventricular nucleus (PVN), supraoptic nucleus (SON), infundibular nucleus and medial mamillary nucleus. No staining was observed in the sexually dimorphic nucleus of preoptic area, tuberomamillary nucleus and lateral hypothalamic area. RARα was co-localized with vasopressin (AVP) neurons in the SCN, PVN and SON, and co-localized with corticotropin releasing hormone (CRH) neurons in the PVN. These findings provide a neurobiological basis for the participation of retinoids in the regulation of various hypothalamic functions. As shown earlier, the co-localization of RARα in CRH neurons suggests that retinoids might directly modulate the hypothalamus-pituitary-adrenal axis in the PVN, which may have implications for the stress response and its involvement in mood disorders. Functional studies in the other sites of RARα localization have to follow in the future.


Assuntos
Hipotálamo/metabolismo , Receptores do Ácido Retinoico/metabolismo , Idoso , Idoso de 80 Anos ou mais , Hormônio Liberador da Corticotropina/metabolismo , Feminino , Humanos , Hipotálamo/anatomia & histologia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neurônios/metabolismo , Receptor alfa de Ácido Retinoico , Vasopressinas/metabolismo
16.
J Med Eng Technol ; 34(4): 285-90, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20397850

RESUMO

Bioactive glass, an osteoproductive material, has received considerable attention as a bone graft substitute in the treatment of bony defects. Bioactive CaO-SiO(2)-P(2)O(5) glass was prepared using the sol-gel method, and mineralization behaviour in vitro was investigated by soaking it in simulated body fluid (SBF). Cellular cultivation in vitro, MTT (3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide) and Von Kossa assays were conducted to evaluate the osteoblast response to the bioactive glass. A calcium phosphate carbonate hydroxide (HCA) layer was formed on the bioactive glass after soaking for 3 days in SBF, which indicated that the mineralization on the surface of bioactive glass could progress spontaneously. The osteoblast response results demonstrated that bioactive glass had no cytotoxicity, and it might not be harmful to the morphology of the osteoblast. The growth and proliferation of the osteoblastic cell could not be inhibited. Nodule formation was also observed in conditioned medium containing dissolution bioactive glass and these nodules were shown to be mineralized by Von Kossa staining, which indicates that bioactive glass shows good biocompatibility.


Assuntos
Calcificação Fisiológica/fisiologia , Vidro , Osteoblastos/metabolismo , Materiais Biocompatíveis/efeitos adversos , Calcificação Fisiológica/efeitos dos fármacos , Células Cultivadas , Humanos , Masculino , Teste de Materiais , Osteoblastos/efeitos dos fármacos
17.
Neuroscience ; 159(3): 1126-34, 2009 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-19356693

RESUMO

Acid-sensing ion channels (ASICs), the members of the epithelial sodium channel/degenerin (ENaC/DEG) superfamily, are proton-gated voltage-insensitive cation channels. Six ASIC subunits have been identified and characterized in the mammalian nervous system so far. Of these subunits, ASIC3 has been shown to be predominantly expressed in the peripheral nervous system of rodents and implicated in mechnosensation, chemosensation and pain perception. Little is known on ASIC3 in the brain. We thus employed reverse transcription-polymerase chain reaction (RT-PCR) and Western blot to examine the expression of ASIC3 in various rat brain regions, including hippocampus, amygdala, caudate putamen, prefrontal cortex, and hypothalamus. Specific attention was paid to the distribution of ASIC3 in the hypothalamus of rats by using immunohistochemistry. ASIC3 immunoreactivity showed a widespread pattern throughout the hypothalamus, with the highest density in paraventricular nucleus, supraoptic nucleus, suprachiasmatic nucleus, arcuate nucleus, dorsomedial nucleus, median preoptic nucleus, ventromedial preoptic nucleus, and dorsal tuberomammillary nucleus. This study may contribute to the understanding of ASIC3 functions in the CNS.


Assuntos
Encéfalo/metabolismo , Hipotálamo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Canais de Sódio/metabolismo , Canais Iônicos Sensíveis a Ácido , Animais , Anticorpos , Western Blotting , Gânglios Espinais/metabolismo , Imuno-Histoquímica , Masculino , Proteínas do Tecido Nervoso/imunologia , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Canais de Sódio/imunologia , Tubulina (Proteína)/metabolismo
18.
Mol Psychiatry ; 13(8): 786-99, 741, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18427561

RESUMO

Hyperactivity of corticotropin-releasing factor (CRF) neurons in the paraventricular nucleus (PVN) of the hypothalamus is a prominent feature in depression and may be important in the etiology of this disease. The activity of the CRF neurons in the stress response is modulated by a number of factors that stimulate or inhibit CRF expression, including (1) corticosteroid receptors and their chaperones, heat shock proteins 70 and 90, (2) sex hormone receptors, (3) CRF receptors 1 (CRFR1) and 2, (4) cytokines interleukin 1-beta and tumor necrosis factor-alpha, (5) neuropeptides and receptors, vasopressin (AVP), AVP receptor 1a (AVPR1A) and oxytocin and (6) transcription factor cAMP-response element-binding protein. We hypothesized that, in depression, the transcript levels of those genes that are involved in the activation of the hypothalamo-pituitary-adrenal (HPA) axis are upregulated, whereas the transcript levels of the genes involved in the inhibition of the HPA axis are downregulated. We performed laser microdissection and real-time PCR in the PVN and as a control in the supraoptic nucleus. Snap-frozen post-mortem hypothalami of seven depressed and seven matched controls were used. We found significantly increased CRF mRNA levels in the PVN of the depressed patients. This was accompanied by a significantly increased expression of four genes that are involved in the activation of CRF neurons, that is, CRFR1, estrogen receptor-alpha, AVPR1A and mineralocorticoid receptor, while the expression of the androgen receptor mRNA involved in the inhibition of CRF neurons was decreased significantly. These findings raise the possibility that a disturbed balance in the production of receptors may contribute to the activation of the HPA axis in depression.


Assuntos
Transtorno Bipolar/genética , Depressão/genética , Expressão Gênica , Hipotálamo/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipotálamo/patologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Mudanças Depois da Morte , Receptores Citoplasmáticos e Nucleares/genética
19.
Eur J Neurol ; 14(2): 150-5, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17250722

RESUMO

The aim of this study was to investigate the changes in cerebral blood flow velocity (CBFV) and its relation to apolipoprotein E (apoE) epsilon4 allele in mild cognitive impairment (MCI). Thirty MCI and 30 controls were assessed using Mini-Mental State Examination (MMSE) and Cambridge Cognitive Examination-Chinese version (CAMCOG-C), and then insonated in the anterior (ACA), middle (MCA) and basilar (BA) cerebral arteries using transcranial Doppler ultrasonography. Compared with controls, MCI showed significant decreases in the mean (V(m)), systolic (V(s)) and diastolic (V(d)) CBFV, bilaterally in MCA and ACA (P < 0.05-0.001), but not in BA. Compared with 17 apoE epsilon4 allele non-carriers, 13 carriers in MCI showed significant CBFV decreases, bilaterally in MCA (P < 0.05-0.001). Our findings, the decreased CBFV in apoE epsilon4 allele carriers with MCI, suggest that a large sample and longitudinal study in CBFV and cognitive changes may have the implications on early diagnosis of Alzheimer's disease.


Assuntos
Alelos , Apolipoproteína E4/genética , Velocidade do Fluxo Sanguíneo , Circulação Cerebrovascular , Transtornos Cognitivos/fisiopatologia , Heterozigoto , Idoso , Artéria Cerebral Anterior/diagnóstico por imagem , Artéria Basilar/diagnóstico por imagem , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/genética , Transtornos Cognitivos/psicologia , Diástole , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Testes Neuropsicológicos , Índice de Gravidade de Doença , Sístole , Ultrassonografia Doppler Transcraniana
20.
Mol Psychiatry ; 11(6): 567-76, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16446741

RESUMO

We investigated the possibility of a direct action of androgens on the expression of the human corticotropin-releasing hormone (CRH), which plays a central role in the hypothalamic-pituitary-adrenal (HPA)-axis. Colocalization of CRH and nuclear/cytoplasmic androgen receptor (AR) was found in neurons of the paraventricular nucleus (PVN) in the human hypothalamus. A potential androgen-responsive element (ARE) in the human CRH promoter was subsequently analyzed with bandshifts and cotransfections in neuroblastoma cells. In the presence of testosterone, recombinant human AR bound specifically to the CRH-ARE. Expression of AR in combination with testosterone repressed CRH promoter activity through the ARE. We conclude that androgens may directly affect CRH neurons in the human PVN via AR binding to the CRH-ARE, which may have consequences for sex-specific pathogenesis of mood disorders.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Receptores Androgênicos/metabolismo , Elementos de Resposta/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Hormônio Liberador da Corticotropina/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Humor/fisiopatologia , Elementos de Resposta/genética , Testosterona/fisiologia , Distribuição Tecidual
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