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1.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(5): 660-666, 2021 May 06.
Artigo em Chinês | MEDLINE | ID: mdl-34034408

RESUMO

Objective: This study was aimed to analyze the untargeted metabolomics of serum samples from children with mycoplasma pneumonia in a hospital in Beijing. Methods: A total of 50 children with mycoplasma pneumonia as the case group were recruited from Department of Pediatrics, China-Japan Friendship Hospital in Beijing from January 2019 to February 2020, and meanwhile 50 age-and gender-matched heathy children were selected and formed the control group. 2 ml venous fasting blood samples was collected from all children. Serum metabolites were quantified by using the untargeted ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) technique. Unsupervised principle component analysis and (orthogonal) partial least-squares-discriminant analysis were employed to identify differential metabolites between cases and controls. MBRole software was used for pathway enrichment analysis. Results: There were 27 boys and 23 girls in the case group with an average age of (6.0±3.65) years, and the control group consisted of 28 boys and 22 girls with an average age of (6.62±2.64) years. A total of 392 different metabolites were detected. Compared with the control group, 306 metabolites were decreased and 86 increased in case group. Forty-one differential metabolites with variable important in projection (VIP) values larger than 5 and P values less than 0.05 were teased out, and they mainly concentrated on phospholipid. The levels of 38 metabolites were significantly lower in the case group, yet 4 metabolites were significantly higher than that of the control group. Metabolic enrichment analysis showed that different metabolites were related to the biosynthesis of phenylalanine, tyrosine, tryptophan, unsaturated fatty acid, ammonia acyl tRNA and insulin signaling pathway, as well as the metabolism of ABC transporters. Conclusion: The serum untargeted metabolomics differed remarkably between children with mycoplasma pneumonia and healthy children.


Assuntos
Pneumonia por Mycoplasma , Biomarcadores , Criança , Pré-Escolar , China , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Feminino , Hospitais , Humanos , Masculino , Metaboloma , Metabolômica , Espectrometria de Massas em Tandem
2.
Gene Ther ; 24(6): 353-360, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28440797

RESUMO

The present study aimed to investigate the potential role of microRNA-141-3p (miR-141-3p) in chronic inflammatory pain (CIP) by targeting the high-mobility group box1 (HMGB1) gene. In the in vitro study, BV2 microglial cells were selected and assigned into blank, lipopolysaccharide (LPS), miR-141-3p mimics, mimics control, miR-141-3p inhibitor, inhibitor control, miR-141-3p mimics+LPS, mimics control+ LPS, miR-141-3p inhibitor+LPS and inhibitor control+LPS groups. Ninety-six rats were randomly divided into 8 groups (12 rats in each group): blank control, model control, negative control (NC), miR-141-3p mimics+ complete Freund's adjuvant (CFA), mimics control+CFA, HMGB1 short hairpin RNA (shRNA)+CFA, HMGB1 NC+CFA and miR-141-3p mimics+HMGB1 shRNA+CFA groups. The quantitative real-time PCR, western blotting, enzyme-linked immunosorbent assay and pain behavioral test were used to measure the miR-141-3p and HMGB1 mRNA expressions, HMGB1 protein expression, inflammatory cytokines levels, and thermal and mechanical pain thresholds, respectively. Compared with the blank, mimics control, inhibitor control and miR-141-3p mimics+LPS groups, the miR-141-3p mimics group had increased miR-141-3p expression and interleukin (IL)-10 levels, and had decreased mRNA and protein expressions of HMGB1 and the levels of IL-1ß, tumor necrosis factor-α (TNF-α) and IL-6, whereas the opposite trend were found in the LPS, miR-141-3p inhibitor, mimics control+LPS and inhibitor control+LPS groups. Compared with the LPS, miR-141-3p inhibitor, mimics control+LPS and inhibitor control+LPS groups, the miR141-3p+LPS group had an obviously decreased expression of miR-141-3p and IL-10, increased mRNA and protein expressions of HMGB1 and the levels of IL-1ß, TNF-α and IL-6. Compared with the rats in the blank control group, the miR-141-3p expression, IL-10 level, and thermal and mechanical pain thresholds decreased significantly, whereas the mRNA and protein expressions of HMGB1, IL-1ß, TNF-α and IL-6 increased significantly in rats in the NC, mimics control+CFA and HMGB1 NC+ CFA groups. The miR-141-3p expression was increased in rats in the miR-141-3p mimics+HMGB1 shRNA+CFA group. Our study demonstrated that miR-141-3p can alleviate the CIP by downregulating the downstream target gene HMGB1.


Assuntos
Dor Crônica/terapia , Regulação para Baixo , Terapia Genética/métodos , Proteína HMGB1/genética , MicroRNAs/genética , Neuralgia/terapia , Animais , Linhagem Celular , Citocinas/sangue , Proteína HMGB1/metabolismo , Camundongos , Limiar da Dor , Ratos , Ratos Sprague-Dawley
3.
Environ Entomol ; 44(4): 1230-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26314069

RESUMO

Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), a worldwide distributive invasive pest, originated from the United States, and it was first reported in Guangdong province, China, in 2008. The effects of temperature and relative humidity (RH) on the life history traits of P. solenopsis on Hibiscus rosa-sinensis L. (Malvales: Malvaceae) were studied at seven constant temperatures (15, 20, 25, 27.5, 30, 32.5, and 35°C) and three RHs (45, 60, and 75%). The results showed that temperature, RH, and their interactions significantly influenced the life history traits of P. solenopsis. First instar was the most sensitive stage to extreme temperatures with very low survival rates at 15 and 35°C. At 25-32.5°C and the three RHs, the developmental periods of entire immature stage were shorter with values between 12.5-18.6 d. The minimum threshold temperature and the effective accumulative temperature for the pest to complete one generation were 13.2°C and 393.7 degree-days, respectively. The percentage and longevity of female adults significantly differed among different treatments. It failed to complete development at 15 or 35°C and the three RHs. Female fecundity reached the maximum value at 27.5°C and 45% RH. The intrinsic rate for increase (r), the net reproductive rate (R0), and the finite rate of increase (λ) reached the maximum values at 27.5°C and 45% RH (0.22 d(-1), 244.6 hatched eggs, and 1.25 d(-1), respectively). Therefore, we conclude that 27.5°C and 45% RH are the optimum conditions for the population development of the pest.


Assuntos
Cadeia Alimentar , Hemípteros/crescimento & desenvolvimento , Hibiscus , Animais , Hibiscus/crescimento & desenvolvimento , Umidade , Espécies Introduzidas , Temperatura
4.
Plant Dis ; 97(3): 422, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30722386

RESUMO

An anthracnose disease was observed on stems of high-bush blueberry plants (Vaccinium corymbosum L.) in Liaoning Province, China in 2012. The typical symptoms consist of sudden wilting and dieback of stems during the growing season. Dark brown lesions originate from infected buds and kill portions of the stems. Lesions have grayish white centers, with the necrotic areas becoming 6 to 8 cm in length. Disinfected stem pieces were placed on potato dextrose agar (PDA) and incubated at 28°C for 5 to 7 days, after which the emerging colonies were transferred to fresh PDA. All isolates initially produced white growth, but turned pink after 7 days before becoming blackish green. The average colony diameter was 65.5 to 75.0 mm after 7 days. Conidia were aseptate, hyaline, fusiform to ellipsoid, 8.5 to 16.5 × 2.5 to 4.0 µm in size and single celled with two to seven oil globules. Setae were not found on the acervuli. These characteristics matched published descriptions of Colletotrichum acutatum (1) (teleomorph Glomerella acutata). Pathogenicity test was confirmed in 15 2-year-old healthy potted plants of cv. Berkeley. Stems of 10 plants were punctured with flamed needles and sprayed with 5 ml of conidial suspension (106 conidia per ml in sterile distilled water) of isolate LNSW1. Five control plants were inoculated with sterile distilled water. Seven days after inoculation, eight of the 10 blueberry plants exhibited stem lesions, leaf chlorosis, followed by branch dieback 15 days post-inoculation. The symptoms were similar to those observed on diseased plants in the field, and no lesions were observed on control plants. The pathogen was reisolated from the margin of lesions and identified by colony growth characteristics on PDA. PCR amplification of one isolate (LNSW1) was carried out by utilizing the universal rDNA-ITS primer pair ITS1/ITS4. The sequence (557 bp) of isolate LNSW1 (GenBank Accession No. JX392857) showed 99% identity to G. acutata (AB443950) and C. acutatum (AJ749672) in a BLAST search. An approximately 490-bp fragment was amplified from LNSW1 by the species-specific primer pair CaInt2/ITS4 (2). The pathogen was identified as G. acutata (asexual stage: C. acutatum J.H. Simmonds) on the basis of morphological characters, rDNA-ITS sequence analysis, and a PCR product with species-specific primers. To our knowledge, this is the first report of C. acutatum in high-bush blueberry plants in China. References: (1) C. Lei et al. Fungal Diversity 12:183, 2009. (2) S. Sreenivasaprasad et al. Plant Pathol. 45:650, 1996.

5.
Plant Dis ; 97(6): 845, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30722632

RESUMO

Blueberry (Vaccinium spp.) is becoming increasingly popular in China as a nutritional berry crop. With the expansion of blueberry production, many diseases have become widespread in different regions of China. In August of 2012, stem and leaf spots symptomatic of anthracnose were sporadically observed on highbush blueberries in a field located in Liaoning, China, where approximately 15% of plants were diseased. Symptoms first appeared as yellow to reddish, irregularly-shaped lesions on leaves and stems. The lesions then expanded, becoming dark brown in the center and surrounded by a reddish halo. Leaf and stem tissues (5 × 5 mm) were cut from the lesion margins and surface-disinfected in 70% ethanol for 30 s, followed by three rinses with sterile water before placing on potato dextrose agar (PDA). Plates were incubated at 28°C. Colonies were initially white, becoming grayish-white to gray with yellow spore masses. Conidia were one-celled, hyaline, and cylindrical with rounded ends, measuring 15.0 to 25.0 × 4.0 to 7.5 µm. No teleomorph was observed. The fungus was tentatively identified as Colletotrichum gloeosporioides (PenZ.) PenZ & Sacc. (teleomorph Glomerella cingulata (Stoneman) Spauld. & H. Schrenk) based on morphological characteristics of the colony and conidia (1). Genomic DNA was extracted from isolate XCG1 and the internal transcribed spacer (ITS) region of the ribosomal DNA (ITS1-5.8S-ITS2) was amplified with primer pairs ITS1 and ITS4. BLAST searches showed 99% identity with C. gloeosporioides isolates in GenBank (Accession No. AF272779). The sequence of isolate XCG1 (C. gloeosporioides) was deposited into GenBank (JX878503). Pathogenicity tests were conducted on 2-year-old potted blueberries, cv. Berkeley. Stems and leaves of 10 potted blueberry plants were wounded with a sterilized needle and sprayed with a suspension of 105 conidia per ml of sterilized water. Five healthy potted plants were inoculated with sterilized water as control. Dark brown lesions surrounded by reddish halos developed on all inoculated leaves and stems after 7 days, and the pathogen was reisolated from lesions of 50% of inoculated plants as described above. The colony and conidial morphology were identical to the original isolate XCG1. No symptoms developed on the control plants. The causal agent of anthracnose on blueberry was identified as C. gloeosporioides on the basis of morphological and molecular characteristics, and its pathogenicity was confirmed with Koch's postulates. Worldwide, it has been reported that blueberry anthracnose might be caused by C. acutatum and C. gloeosporioides (2). However, we did not isolate C. acutatum during this study. To our knowledge, this is the first report of stem and leaf anthracnose of blueberry caused by C. gloeosporioides in China. References: (1) J. M. E. Mourde. No 315. CMI Descriptions of Pathogenic Fungi and Bacteria. Kew, Surrey, UK, 1971. (2) N. Verma, et al. Plant Pathol. 55:442, 2006.

6.
West Indian Med J ; 61(2): 202-3, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23155971

RESUMO

A 43-year old man acquired acute hepatitis C virus (HCV) infection with unclear route of transmission. There were no known sexual or other risk factors for HCV acquisition. Phylogenetic analysis confirmed that the case was infected with identical genotype 1b strain. After symptomatic treatment for three weeks, the HCV was spontaneously cleared and liver function recovered.


Assuntos
Hepatite C/transmissão , Doença Aguda , Adulto , Hepatite C/tratamento farmacológico , Humanos , Masculino
7.
Genet Mol Res ; 11(4): 4707-10, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23096907

RESUMO

We isolated and characterizated 12 polymorphic microsatellite loci in the rapid racerunner Eremias velox (Squamata: Lacertidae). The loci were screened in 37 E. velox individuals. The number of alleles ranged from 6 to 16. The observed heterozygosity ranged from 0.432 to 0.919, and the expected heterozygosity ranged from 0.685 to 0.902. These microsatellite markers should prove useful for population genetic studies of E. velox and other Eremias species.


Assuntos
Repetições de Microssatélites , Polimorfismo Genético , Alelos , Animais , Sequência de Bases , Conservação dos Recursos Naturais , Loci Gênicos , Heterozigoto , Lagartos/genética , Análise de Sequência de DNA
8.
Andrologia ; 43(5): 303-6, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21793865

RESUMO

The aim of this study was to investigate the effect and significance of l-arginine and ageing on nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) pathway and ET-1 in penile tissue of rats. The different months old rats were divided into control group and experiment group randomly, the content of NO, cGMP, the changes of activity of Nitrous Oxide Systems (NOS) and the content of endothelin-1(ET-1) in penile tissue were determined. Along with ageing, NO and the activity of NOS in penile tissue increased at first and then decreased (P < 0.001). The content of cGMP reduced obviously (P < 0.001), the content of ET-1 had a tendency to increase, and the ratio of ET-1/NO increased significantly (P < 0.001 or P < 0.01). After feeding rats with l-arginine for some time, both the activity of NOS and the content of cGMP increased significantly in penile tissue (P < 0.001), while there was no obvious change in the content of ET-1. Our study shows that whether the smooth muscle cells relax or contract might be decided by the content of cGMP and value of ET-1/NO in penile tissue. l-arginine had significant effect on increasing the activity of NOS and the content of NO and cGMP, indicating that l-arginine has potential clinical value to be used in treating ED.


Assuntos
Envelhecimento/metabolismo , Arginina/farmacologia , Endotelina-1/metabolismo , Óxido Nítrico/metabolismo , Pênis/efeitos dos fármacos , Animais , GMP Cíclico/metabolismo , Masculino , Óxido Nítrico Sintase/metabolismo , Pênis/enzimologia , Pênis/metabolismo , Ratos , Ratos Wistar
9.
J Int Med Res ; 38(6): 1913-22, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21226994

RESUMO

Increasing evidence suggests that the activity of cysteine proteases, including cathepsin L, is important in cancer cell invasion and metastasis. This study was designed to investigate the clinicopathological and prognostic significance of cathepsin L in human urothelial carcinoma of the bladder (UCB). Standard immunohistochemistry was used to determine the presence of cathepsin L and Ki-67 (a marker of proliferation) in paraffin-embedded specimens of 82 human UCB cases. Cathepsin L protein was localized in the cytoplasm of the malignant UCB cells, and was significantly associated with the pathological tumour stage (invasiveness), tumour grade, survival, local tumour recurrence during follow-up, the occurrence of distant metastasis during follow-up and the presence of Ki-67 protein. Multivariate analysis using the Cox proportional hazards model revealed that cathepsin L immunopositivity and pathological tumour stage (invasiveness) were independent significant prognostic factors for overall survival. This study showed that cathepsin L provides significant prognostic information and that it might be a useful therapeutic target in the future.


Assuntos
Catepsina L/metabolismo , Neoplasias da Bexiga Urinária/enzimologia , Neoplasias da Bexiga Urinária/patologia , Urotélio/enzimologia , Urotélio/patologia , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células , Citoplasma/enzimologia , Citoplasma/patologia , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais , Resultado do Tratamento
10.
Neurosci Lett ; 315(1-2): 98-102, 2001 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-11711224

RESUMO

Small dorsal root ganglion (DRG) neurons are characterized by sensitivity to capsaicin. In acutely isolated rat DRG neurons, the effect of neomycin, one of the aminoglycoside antibiotics, on capsaicin-evoked current and voltage responses was examined using whole-cell patch-clamp recording. We showed for the first time that neomycin dose-dependently inhibited capsaicin-evoked currents with half-maximal inhibitory concentration at 130.60 microM (n=70). Under current-clamp condition, depolarization and firing rate evoked by capsaicin became weakened when neomycin was perfused to the neurons (n=10). Neomycin had no significant effect on the resting potentials of DRG neurons. These results suggest that neomycin could inhibit capsaicin-sensitive responses in small DRG neurons, which may contribute to neomycin-induced peripheral analgesia.


Assuntos
Analgésicos/farmacologia , Antibacterianos/farmacologia , Capsaicina/farmacologia , Gânglios Espinais/citologia , Neomicina/farmacologia , Neurônios/efeitos dos fármacos , Animais , Potenciais Evocados , Técnicas In Vitro , Masculino , Potenciais da Membrana , Neurônios/fisiologia , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley
11.
Neuropharmacology ; 41(5): 601-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11587715

RESUMO

Capsaicin activates a non-specific cation conductance in a subset of dorsal root ganglion (DRG) neurons. The inward current and membrane potential of acutely isolated DRG neurons were examined using whole-cell patch recording methods. We report here that the current and voltage responses activated by capsaicin were markedly increased by phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C (PKC). The mean current, after application of 0.3 microM PMA, was 153.5+/-5.7% of control (n=32) in Ca(2+)-free external solution and 181.6+/-6.8% of control (n=15) in standard external solution. Under current-clamp conditions, 0.3 microM PMA facilitated capsaicin-induced depolarization and action potential generation. Bindolylmaleimide I (BIM), a specific inhibitor of PKC activity, abolished the effect of PMA. In addition, capsaicin-evoked current was attenuated to 68.3+/-5.0% of control (n=13) by individual administration of 1 microM BIM in standard external solution, while 0.3 microM BIM did not have this effect. These data suggest that PKC can directly regulate the capsaicin response in DRG neurons, which could increase nociceptive sensory transmission and contribute to hyperalgesia.


Assuntos
Capsaicina/farmacologia , Gânglios Espinais/fisiologia , Neurônios/fisiologia , Proteína Quinase C/fisiologia , Animais , Células Cultivadas , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/enzimologia , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/enzimologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
12.
Bioorg Med Chem Lett ; 11(17): 2331-5, 2001 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-11527725
13.
Biochemistry ; 40(4): 987-93, 2001 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-11170420

RESUMO

X-ray absorption spectroscopy has been used to investigate binding of selenohomocysteine to cobalamin-independent (MetE) and cobalamin-dependent (MetH) methionine synthase enzymes of Escherichia coli. We have shown previously [Peariso et al. (1998) J. Am. Chem. Soc. 120, 8410-8416] that the Zn sites in both enzymes show an increase in the number of sulfur ligands when homocysteine binds. The present data provide direct evidence that this change is due to coordination of the substrate to the Zn. Addition of L-selenohomocysteine to either MetE or the N-terminal fragment of MetH, MetH(2-649), causes changes in the zinc X-ray absorption near-edge structure that are remarkably similar to those observed following the addition of L-homocysteine. Zinc EXAFS spectra show that the addition of L-selenohomocysteine changes the coordination environment of the zinc in MetE from 2S + 2(N/O) to 2S + 1(N/O) + 1Se and in MetH(2-649) from 3S + 1(N/O) to 3S + 1Se. The Zn-S, Zn-Se, and Se-S bond distances determined from the zinc and selenium EXAFS data indicate that the zinc sites in substrate-bound MetE and MetH(2-649) both have an approximately tetrahedral geometry. The selenium edge energy for selenohomocysteine shifts to higher energy when binding to either methionine synthase enzyme, suggesting that there is a slight decrease in the effective charge of the selenium. Increases in the Zn-Cys bond distances upon selenohomocysteine binding together with identical magnitudes of the shifts to higher energy in the Se XANES spectra of MetE and MetH(2-649) suggest that the Lewis acidity of the Zn sites in these enzymes appears the same to the substrate and is electronically buffered by the Zn-Cys interaction.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/química , Cisteína/análogos & derivados , Proteínas de Escherichia coli , Selênio/química , Vitamina B 12/química , Zinco/química , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Cisteína/metabolismo , Escherichia coli/enzimologia , Metiltransferases , Compostos Organosselênicos/metabolismo , Selenocisteína/análogos & derivados , Análise Espectral/métodos , Especificidade por Substrato , Raios X , Zinco/metabolismo
14.
Bioorg Med Chem Lett ; 10(21): 2471-5, 2000 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-11078203

RESUMO

A single-step convenient synthesis of L-selenohomocysteine (SeHcy) from L-selenomethionine (SeMet) using sodium in liquid ammonia is described. Methionine synthases convert SeHcy to SeMet at rates comparable to their rates of conversion of L-homocysteine (Hcy) to L-methionine (Met). This study suggests that SeHcy generated from SeMet metabolism can be efficiently recycled to SeMet in mammals.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Cisteína/análogos & derivados , Cisteína/síntese química , Cisteína/metabolismo , Compostos Organosselênicos/síntese química , Compostos Organosselênicos/metabolismo , Selênio/metabolismo , Selenometionina/metabolismo , Animais , Anticarcinógenos/síntese química , Anticarcinógenos/metabolismo , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Cinética , Masculino , Estrutura Molecular , Oxirredução , Selenocisteína/análogos & derivados , Selenometionina/química
15.
Brain Res Bull ; 52(5): 427-33, 2000 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10922523

RESUMO

Ketamine, a general anesthetic, has been reported to block sodium channels. Two types of Na(+) channels, tetrodotoxin (TTX)-sensitive (TTX-s) and TTX-resistant (TTX-r), are expressed in dorsal root ganglion (DRG) neurons. The present study was to investigate the effects of ketamine on both types, particularly on TTX-r channels, using whole-cell patch-clamp recordings in dissociated rat DRG neurons. In addition to confirming ketamine-induced blockage of TTX-s Na(+) current, we showed for the first time that ketamine blocked TTX-r Na(+) channels on small DRG neurons in dose-dependent and use-dependent manner. Half-maximal inhibitory concentration (IC(50)) was 866.2 microM for TTX-r Na(+) channels. TTX-r Na(+) channels were more sensitive to ketamine in inactivated state (IC(50) = 314.8 microM) than in resting state (IC(50) = 866.2 microM). IC(50) was 146.7 microM for TTX-s Na(+) current. Activation and inactivation properties of both TTX-s and TTX-r Na(+) channels were affected by ketamine. Since TTX-r Na(+) channels were preferentially expressed in small DRG neurons known as nociceptors, blockage of TTX-r Na(+) channels by ketamine may result in reducing nociceptive signals conducting to the spinal cord. Moreover, both TTX-r and TTX-s Na(+) channels would be non-selectively blocked by ketamine at high concentration, suggesting that the high dose of ketamine might produce an action of local anesthesia.


Assuntos
Gânglios Espinais/efeitos dos fármacos , Ketamina/farmacologia , Células do Corno Posterior/efeitos dos fármacos , Bloqueadores dos Canais de Sódio , Tetrodotoxina/farmacologia , Potenciais de Ação/efeitos dos fármacos , Anestésicos Dissociativos/farmacologia , Animais , Capsaicina/farmacologia , Separação Celular , Tamanho Celular , Relação Dose-Resposta a Droga , Feminino , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Técnicas In Vitro , Ativação do Canal Iônico/efeitos dos fármacos , Masculino , Técnicas de Patch-Clamp , Células do Corno Posterior/citologia , Células do Corno Posterior/metabolismo , Ratos , Ratos Sprague-Dawley , Sódio/metabolismo , Canais de Sódio/metabolismo
16.
Neurosci Lett ; 287(1): 57-60, 2000 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-10841990

RESUMO

Substance P (SP) plays an important role in sensitization of spinal cord neurons. In this study, we investigated SP-induced calcium activities in cultured rat spinal cord neurons with confocal laser scanning microscopy. Our results showed that SP increased [Ca(2+)](i) by calcium entry rather than release from intracellular calcium stores. Neomycin (100 microM), an antagonist of phosphatidylinositol 4,5-bisphosphate (PIP(2)), blocked SP-induced calcium entry. Ca(2+)-free medium induced capacitative entry, which was significantly potentiated by SP. As activation of SP receptor (NK-1) leads to production of inositol 1,4,5-trisphosphate (IP(3)) by PIP(2) turnover, the results indicates that SP-induced calcium entry and SP-potentiated capacitative calcium entry might be mediated or regulated by IP(3)/diacylglycerol (DG) pathway.


Assuntos
Canais de Cálcio/efeitos dos fármacos , Neomicina/farmacologia , Neurônios/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Substância P/metabolismo , Substância P/farmacologia , Animais , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Células Cultivadas , Embrião de Mamíferos , Microscopia Confocal , Neurônios/citologia , Neurônios/metabolismo , Ratos , Medula Espinal/citologia , Medula Espinal/metabolismo
17.
Biochemistry ; 38(48): 15915-26, 1999 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-10625458

RESUMO

Cobalamin-independent methionine synthase (MetE) from Escherichia coli catalyzes the transfer of a methyl group from methyltetrahydrofolate to homocysteine to form tetrahydrofolate and methionine. It contains 1 equiv of zinc that is essential for its catalytic activity. Extended X-ray absorption fine structure analysis of the zinc-binding site has suggested tetrahedral coordination with two sulfur (cysteine) and one nitrogen or oxygen ligands provided by the enzyme and an exchangeable oxygen or nitrogen ligand that is replaced by the homocysteine thiol group in the enzyme-substrate complex [González, J. C., Peariso, K., Penner-Hahn, J. E., and Matthews, R. G. (1996) Biochemistry 35, 12228-34]. Sequence alignment of MetE homologues shows that His641, Cys643, and Cys726 are the only conserved residues. We report here the construction, expression, and purification of the His641Gln, Cys643Ser, and Cys726Ser mutants of MetE. Each mutant displays significantly impaired activity and contains less than 1 equiv of zinc upon purification. Furthermore, each mutant binds zinc with lower binding affinity (K(a) approximately 10(14) M(-)(1)) compared to the wild-type enzyme (K(a) > 10(16) M(-)(1)). All the MetE mutants are able to bind homocysteine. X-ray absorption spectroscopy analysis of the zinc-binding sites in the mutants indicates that the four-coordinate zinc site is preserved but that the ligand sets are changed. Our results demonstrate that Cys643 and Cys726 are two of the zinc ligands in MetE from E. coli and suggest that His641 is a third endogenous ligand. The effects of the mutations on the specific activities of the mutant proteins suggest that zinc and homocysteine binding alone are not sufficient for activity; the chemical nature of the ligands is also a determining factor for catalytic activity in agreement with model studies of the alkylation of zinc-thiolate complexes.


Assuntos
5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/química , Escherichia coli/enzimologia , Zinco/química , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/biossíntese , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Sequência de Aminoácidos , Sítios de Ligação , Quelantes , Homocisteína/química , Ligantes , Dados de Sequência Molecular , Mutação , Alinhamento de Sequência , Vitamina B 12/química , Zinco/análise
18.
Zhonghua Bing Li Xue Za Zhi ; 23(2): 89-92, 1994 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-8082247

RESUMO

One hundred and four thymuses from patients with myasthenia gravis were reviewed for clinical pathological manifestations. 6 cases were examined by immunohistochemical techniques with CK, EMA, CEA, UCHT1, T4, T8, L26, S-100 and electronmicroscopy. 73 cases had long term follow-up after thymectomy. Microscopically, there was lymphocytic hyperplasia associated with formation of germinal centers and branching proliferation of capillaries, which were characteristic. Electronmicroscopically there were abundant cytoplasmic projections of lymphocytes. Interdigitating pattern of the projections were frequently seen between the lymphocytes and crevice-like patterns were formed between the endothelial cells of capillaries. Immunohistochemically, the thymus had both proliferation of T cells (UCHT1, T4) and B cell reaction (L26) as well as CK and S-100 positive cell expression. It is suggested that the prognosis of myasthenia gravis after resection of thymus is related to clinical type, age and pathological changes. 95.1% of adult type I or II cases which were associated with hyperplasia of lymphoid tissue of the thymus, but not thymomas, improved after thymectomy and had better prognosis than others.


Assuntos
Miastenia Gravis/patologia , Timo/patologia , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/cirurgia , Prognóstico , Linfócitos T/ultraestrutura , Timectomia
19.
Zhonghua Yi Xue Za Zhi ; 73(9): 541-3, 575, 1993 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-8313198

RESUMO

Segmental small bowel allografts in pigs were examined histologically to elucidate the rejection process. The specimens were obtained by biopsy at regular intervals after transplantation. Early characteristics of acute rejection were marked by infiltration of mononuclear cells in the lamina propria. Moderate rejection showed increased infiltrated mononuclear cells and mucosal lesions. Mucosal necrosis occurred in the acute phase of rejection. Rejection was seen in the animals that received only low-dose cyclosporin A but not in those treated with tripterygium wilfordii (TW) and low-dose cyclosporin A. These results suggest that mucosal biopsy as a way of monitoring rejection can show sequential pattern of changes. Normal morphological appearance of TW-treated allografts confirmed that TW is an effective immunosuppressant.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Rejeição de Enxerto/prevenção & controle , Imunossupressores/uso terapêutico , Intestino Delgado/transplante , Animais , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Suínos , Tripterygium
20.
JPEN J Parenter Enteral Nutr ; 15(6): 630-6, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1766053

RESUMO

Wistar rats were divided into two groups, intraperitoneal sepsis group (group IS) and total parenteral nutrition group (group TPN), to evaluate the characteristics of pathologic alterations in rats with cholestasis. Biochemical assay showed that cholestasis developed in both groups after 10 days. Light microscopic examination of liver specimens revealed that the degeneration in the intermediate and external zone of hepatolobules was the major alteration in group IS, and group TPN showed characteristic dilation of central veins and hepatic sinuses and the proliferation of Kupffer cells with marked phagocytosis. Electron microscopic pictures presented the enlargement of bile canaliculi with altered microvilli in group IS and many highly electron-dense bile particles within cytoplasm and secondary lysosomes near dilated bile canaliculi in group TPN. It is concluded that there were different histopathologic alterations of liver specimens in TPN-supported animals and septic animals when cholestasis developed. It is unsuitable to take intraperitoneal sepsis as a unique factor of cholestasis in TPN-supported rats. Bile stasis is only one sign of TPN-induced hepatic lesion, which needs further exploration to determine its causes and mechanisms.


Assuntos
Colestase Intra-Hepática/etiologia , Nutrição Parenteral Total/efeitos adversos , Doenças Peritoneais/complicações , Sepse/complicações , Animais , Canalículos Biliares/patologia , Bilirrubina/sangue , Temperatura Corporal , Colestase Intra-Hepática/patologia , Colestase Intra-Hepática/fisiopatologia , Feminino , Contagem de Leucócitos , Fígado/irrigação sanguínea , Fígado/patologia , Microscopia Eletrônica , Microvilosidades/patologia , Mitocôndrias Hepáticas/patologia , Ratos , Ratos Endogâmicos
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