RESUMEN
Objective: To characterize the prevalence and genomic epidemiology of Vibrio parahaemolyticus from acute diarrheal patients in Shenzhen City from 2013 to 2021. Methods: Based on the Shenzhen Infectious Diarrhea Surveillance System, acute diarrheal patients were actively monitored in sentinel hospitals from 2013 to 2021. Whole-genome sequencing (WGS) of Vibrio parahaemolyticus isolates was performed, and the genomic population structure, serotypes, virulence genes and multilocus sequence typing were analyzed. Outbreak clusters from 2019 to 2021 were explored based on single-nucleotide polymorphism analysis. Results: A total of 48 623 acute diarrhea cases were monitored in 15 sentinel hospitals from 2013 to 2021, and 1 135 Vibrio parahaemolyticus strains were isolated, with a positive isolation rate of 2.3%. Qualified whole-genome sequencing data of 852 isolates were obtained. Eighty-nine serotypes, 21 known ST types and 5 new ST types were identified by sequence analysis, and 93.2% of strains were detected with toxin profile of tdh+trh-. 8 clonal groups (CGs) were captured, with CG3 as the absolute predominance, followed by CG189. The CG3 group was dominated by O3:K6 serotype and ST3 sequence type, while CG189 group was mainly O4:KUT, O4:K8 serotypes and ST189a and ST189 type. A total of 13 clusters were identified, containing 154 cases. About 30 outbreak clusters with 29 outbreak clusters caused by CG3 strains from 2019 to 2021. Conclusion: Vibrio parahaemolyticus is a major pathogen of acute infectious diarrhea in Shenzhen City, with diverse population structures. CG3 and CG189 have been prevalent and predominant in Shenzhen City for a long time. Scattered outbreaks and persistent sources of contamination ignored by traditional methods could be captured by WGS analysis. Tracing the source of epidemic clone groups and taking precise prevention and control measures are expected to significantly reduce the burden of diarrhea diseases caused by Vibrio parahaemolyticus infection in Shenzhen City.
Asunto(s)
Humanos , Vibrio parahaemolyticus/genética , Diarrea/epidemiología , Enfermedades Transmitidas por los Alimentos/epidemiología , Serogrupo , Genómica , Disentería , Vibriosis/epidemiología , SerotipificaciónRESUMEN
OBJECTIVE@#To investigate the cytotoxic effect and its mechanism of the micromolecule compound on the leukemia cells.@*METHODS@#The cytotoxic effects of 28 Nilotinib derivatives on K562, KA, KG, HA and 32D cell lines were detected by MTT assays, and the compound Nilo 22 was screen out. Cell apoptosis and cell cycle on leukemia cells were detected by flow cytometry. The effect of compound screened out on leukemogenesis potential of MLL-AF9 leukemia mice GFP@*RESULTS@#Nilo 22 serves as the most outstanding candidate out of 28 Nilotinib derivatives, which impairs leukemia cell lines, but spares normal hematopoietic cell line. Comparing with Nilotinib, Nilo 22 could induce the apoptosis of GFP@*CONCLUSION@#Nilo 22 shows a significant cytotoxic effect on mice and human leukemia cells, especially for drug resistance cells. Nilo 22 is a promising anti-leukemia agent to solve the common clinical problems of drug resistance and relapse of leukemia.
Asunto(s)
Animales , Humanos , Ratones , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Leucemia , Proteína de la Leucemia Mieloide-Linfoide/genética , Telomerasa/metabolismo , Telómero/metabolismoRESUMEN
The innovation and patent layout of traditional Chinese medicine compounds reflects the innovation level of the traditio-nal Chinese medicine industry to a certain extent. Lianhua Qingwen Formula was taken as an example to analyze the innovation and patent layout of traditional Chinese medicine compounds. The study first proposed an innovative technology system for traditional Chinese medicine compounds, and then analyzed the advantages and disadvantages of Lianhua Qingwen Formula in innovation and patent layout based on 56 patents and other relevant patents. The analysis results showed that Lianhua Qingwen Formula had the following characte-ristics in terms of patent layout. In terms of innovation technical route, the patented technical route of Lianhua Qingwen Formula was mainly based on the composition and preparation of granules as the first choice, followed by corresponding process improvements, new uses, and detection methods as the main improvement routes. In terms of the corresponding patent layout, the basic patent protection scope of Lianhua Qingwen Formula completely covered marketed drugs, and then took new functions as the main layout strategy for subsequent patent applications. With the advancement of modern technical means, the preparation process and testing methods have been optimized continuously. At the same time, the international patent layout was given the priority in domestic patent application. Based on the above characteristics, the study gave suggestions for follow-up innovation and patent work for Lianhua Qingwen Formula, so as to provide enlightenment for other traditional Chinese medicine companies in exploring original innovation of traditional Chinese medicine compounds, improving innovative methods, and enhancing the ability of patent layout of innovative achievements.
Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional China , Proyectos de Investigación , TecnologíaRESUMEN
OBJECTIVE@#To study the comprehensive impact of scar and maxillary expansion combined with protraction on the development of maxilla with cleft lip and palate after repair operation.@*METHODS@#In the original finite element model of the maxilla with cleft palate, a finite element model of the maxilla with cleft lip and palate was established by using Boolean operation in ANSYS. Scar force after cleft lip and palate repair and maxillary expansion force combined with protraction were added simultaneously to process the stress analysis.@*RESULTS@#Maxillary deformation occurred in the three-dimensional direction. The comparison of displacements was as follows: X-axis>Z-axis>Y-axis.@*CONCLUSIONS@#Maxillary growth is significantly inhibited in the three-dimensional direction under the comprehensive impact of scar and maxillary expansion combined with protraction after repair operation, especially transverse and sagittal growth.
Asunto(s)
Humanos , Cicatriz/patología , Labio Leporino/cirugía , Fisura del Paladar/cirugía , Análisis de Elementos Finitos , Maxilar/cirugía , Técnica de Expansión PalatinaRESUMEN
OBJECTIVE@#To screen the antioxidant small molecular compounds with optimal efficiency of expansing the human hematopoietic stem cells (hHSC) In vitro based on antioxidant small molecular compound database of LKT laboratory, and to verify the effects of these compounds on the biological functions of hHSC.@*METHODS@#The umbilial cord blood CD34 cells were enriched by using the MACS beads; the absolute number and percentage of CD34 cells and CD34 CD49f cells were detected by high throughput flow cytometry after culture of hHSC with compounds in vitro for 1 week, the SR1 (1 μmol/L) was used as positive control, the candidate compounds were screened out; then 4 compounds were selected for follow-up experiments by comprehensive evaluation of concentration, safety and expansion efficacy, the optimal used concentrations of selected compounds were determined through the concentration gradient analysis, and CFC short-term colony-forming cell test was performed by using the determined concentration so as to verify the effect of compounds on the self-renewal, multilineage differentiation.@*RESULTS@#Out of 85 antioxidant small molecular compounds, 4 compounds (C2968, D3331, B1753 and B3358) with obvious expansion efficacy for CD34 cells and CD34 CD49f cells were screened out by high throughput flow cytometry; their optimal concentrations of 4 compounds were 0.5 μmol/L for C2968, 1.5 μmol/L for D3331 and 1.5 μmol/L for B1753 and 15 μmol/L for B3358. The CFC assay showed the colony formation number in compound-treated group significantly increased as compared with control group, moreover the self-renewal and multilineage differentiation were maintained.@*CONCLUSION@#The antioxidant small molecular compounds C2968 (0.5 μmol/L), D3331 (1.5 μmol/L), B1753 (1.5 μmol/L) and B3358 (1.5 μmol/L) possess good expansion efficacy for hHSC, they can maintain hHSC self-renewal, at the same time ensure the multilineage differentiation potentiality of hHSC.
Asunto(s)
Humanos , Antígenos CD34 , Antioxidantes , Células Cultivadas , Sangre Fetal , Citometría de Flujo , Células Madre HematopoyéticasRESUMEN
Herbal medicine and Chinese materia medica (CMM), Kampo, traditional medicine in Australia, and other traditional medicines have been an important part of the world medicine, and the patent protection strategies of herbal medicine and Kampo at the international level have been already quite mature. However, China have less experience in patent protection strategies of CMM, and apparently fall behind the herbal medicine patent protection strategies of European countries, especially Germany. In this paper, based on the perspective of research and development, the patent application and protection strategies of Tebonin® from Germany are analyzed in depth. Considering patent conservation status of CMM, some workable references for the domestic pharmaceutical enterprises of CMM in the field of research and development of new drugs are provided.
RESUMEN
To investigate the anti-oxidative effect of celastrol on HO-induced oxidative stress in the cell model of amyotrophic lateral sclerosis (ALS) and its molecular mechanism, NSC34 motor neuron-like cells were transfected with EGFP-G93A-SOD1 plasmid and used as in vitro ALS cell model. SOD1transfected NSC34 cells were treated with different doses of HOand celastrol. The survival rate of the cells was detected by CCK-8 assay, and malondialdehyde (MDA) content was detected by corresponding kit. The mRNA expression of glutamate-cysteine ligase catalytic subunit (GCLC) and glutathione S-transferases (GST) were detected by real-time PCR. The activation of intracellular MEK/ERK and PI3K/Akt signal pathways was detected by Western blot. The results showed that pre-incubation of celastrol (50 nmol/L) for 4 h prior to HO(10 μmol/L) co-treatment for another 24 h significantly attenuated HO-induced cell death and MDA level in SOD1transfected NSC34 cells. Real-time PCR showed that the mRNA expressions of GCLC and GST were enhanced with pre-incubation of celastrol. Celastrol quickly induced phosphorylation of ERK1/2 and Akt within 30 min and 1 h respectively in SOD1transfected NSC34 cells. Pharmacological inhibitors of MEK (PD98059, 10 μmol/L) or Akt (MK2206, 10 μmol/L) could reverse the phosphorylation of ERK1/2 and Akt, and abolish up-regulation of GCLC and GST induced by celastrol at mRNA levels. Taken together, we conclude that celastrol exerts a beneficial antioxidant effect in SOD1NSC34 cells, which might be dependent on MEK/ERK and PI3K/Akt signaling pathway activation.
RESUMEN
<p><b>OBJECTIVE</b>To investigate the protective effects of a Chinese herbal formula, taikong yangxin prescription (TKYXP) against bone deterioration in a hindlimb unloaded (tail-suspension) rat model.</p><p><b>METHODS</b>Thirty-two male Sprague-Dawley rats were divided into 4 groups: tail-suspension group fed with 2.5 g•kg(-1)•day(-1) of TKYXP extract (high dose), tail-suspension group fed with 1.25 g•kg(-1)•day(-1) (low dose), tail-suspended group treated with water placebo (placebo control group) and non tail-suspended group. The effects of TKYXP on bone were assessed using peripheral quantitative computed tomography (pQCT), microcomputerized tomography (micro-CT) and three-point bending biomechanical test on the femur in vivo.</p><p><b>RESULTS</b>TKYXP had a significant protective effect against bone loss induced by tail-suspension on day 28, as shown in the reduction in bone mineral density (BMD) loss, preservation of bone micro-architecture and biomechanical strength. The administration ofhigh dose TKYXP could significantly reduce the total BMD loss by 4.8% and 8.0% at the femur and tibia regions, respectively, compared with the placebo control group (P<0.01) on day 28. Its bone protective effect on the femur was further substantiated by the increases of the trabecular BMD (by 6.6%), bone volume fraction (by 20.9%), trabecular number (by 9.5%) and thickness (by 11.9%) as compared with the placebo control group.</p><p><b>CONCLUSION</b>TKYXP may protect the bone under weightless influence from gradual structural deterioration in the tail-suspension model.</p>
Asunto(s)
Animales , Masculino , Ratas , Fenómenos Biomecánicos , Densidad Ósea , Huesos , Diagnóstico por Imagen , Medicamentos Herbarios Chinos , Farmacología , Fémur , Ratas Sprague-Dawley , Tibia , Tomógrafos Computarizados por Rayos X , Ingravidez , Microtomografía por Rayos XRESUMEN
<p><b>OBJECTIVE</b>To study the changes in cardiopulmonary function induced by mid/long-term simulated microgravity with 6° head down bed rest (HDBR), and the effects of Taikong Yangxin Prescription (, TYP) as a countermeasure.</p><p><b>METHODS</b>Fourteen healthy male volunteers were randomly divided into a control group and a Chinese medicine (CM) group (7 in each group) by a random digital table based on their body weight. Both groups underwent 6° HDBR for 60 days. Subjects in the CM group received daily TYP pills and subjects in the control group received daily placebo pills. Cardiac systolic and pumping functions were measured by echocardiography before HDBR; on days 20, 42, and 57 of HDBR; and on day 3 of recovery after HDBR (R+3). Cardiopulmonary functional reserve and exercise capacity were evaluated before HDBR, on day 29, and on day R+3 by exercise testing.</p><p><b>RESULTS</b>The heart rate (HR) increased gradually during HDBR. The HR was significantly higher on day 57 than before HDBR in the control group (P<0.05), but did not increase significantly in the CM group. The stroke volume/stroke volume index, ejection fraction, and left ventricular fractional shortening tended to decrease over time in the control group, but not in the CM group. These parameters were significantly higher in the CM group than in the control group on day 42 (P<0.05 or <0.01). Exercise testing showed that maximum O2 consumption (VO2max), metabolic equivalents, relative O2 consumption (VO2), O2 pulse, and exercise duration were significantly lower on day 29 than before HDBR in the control group, but not in the CM group.</p><p><b>CONCLUSIONS</b>Sixty days of 6° HDBR induced a reduction in cardiac systolic and pumping functions, and reduced cardiopulmonary functional reserve and exercise capacity. Administration of TYP significantly improved cardiac systolic and pumping functions, and maintained cardiopulmonary functional reserve and exercise capacity.</p>
Asunto(s)
Adulto , Humanos , Masculino , Reposo en Cama , Medicamentos Herbarios Chinos , Prueba de Esfuerzo , Corazón , Fisiología , Pulmón , FisiologíaRESUMEN
OBJECTIVE: To establish an LC-MS method to determine the concentrations of metformin, pioglitazone and the active metabolites of pioglitazone(ketopioglitazone M-III and hydroxylpioglitazone M-IV) in plasma after administration of compound metformin and pioglitazone tablets. METHODS: Pioglitazone and the internal standard carbamazepine were extracted from plasma with acetonitrile. The concentrations of pioglitazone and its active metabolites were analyzed on Ultimate C18 column(2.1 mm×150 mm, 5 μm) with mobile phase consisting of acetonitrile-5 mmol·L-1 ammonium acetate(55:45) at a flow rate of 0.3 mL·min-1. The column temperature was 35°C. Metformin and the internal standard memantine were extracted from plasma with acetonitrile and analyzed on Ultimate XB-CN column(2.1 mm×150 mm, 5 μm) with mobile phase consisting of acetonitrile-0.1% formic acid(containing 10 mmol·L-1 ammonium acetate)(73:27) at a flow rate of 0.3 mL·min-1. RESULTS: The liner ranges were 5.08-1016.0 μg·L-1, 2.45-490.0 μg·L-1, and 4.20-840.0 μg·L-1 for metformin, pioglitazone, ketopioglitazone(M-III)and hydroxylpioglitazone(M-IV)respectively. The limits of quantitation were 6.0, 5.08, 2.45, and 4.2 μg·L-1, respectively. The extraction recoveries were more that 89.67%, while the intra- and inter-day precisions(RSD) were less that 15%. CONCLUSION: This assay is accurate, reliable and suitable for pharmacokinetic studies of metformin, pioglitazone and its active metabolites in human plasma.
RESUMEN
<p><b>OBJECTIVE</b>To determine the occurrence and distribution of specific clones of pathogenic Vibrio parahaemolyticus(VP)isolated in Shenzhen and to assess the relationship between serotype O3:K6 and the globally distributed pandemic clone.</p><p><b>METHODS</b>A total of 1005 VPs isolated from diarrhea patients in 2002-2008 were sero-typed. Real-time PCR was used to detect the virulence genes tlh, toxR, tdh, trh and orf8 in 281 isolates from 68 different serotypes. The main serotypes were typed by pulsed field gel electrophoresis(PFGE). Strains with dominant serotypes and PFGE patterns were assayed by GS-PCR and toxRS sequencing for the identification of pandemic clone. Multilocus sequence typing(MLST)analysis was reserved for exemplary 41 O3 : K6 and O1 : K25 isolates.</p><p><b>RESULTS</b>Seventy-nine serotypes were observed among the 1005 isolates, including O3 : K6(57.9%), O4 : K8(8.16%), O1 : KUT(5.87%), O1 : K25(5.27%), O4 : K68(1.39%), O1 : K56(1.39%) and O9 : K44(0.99%). Most of the strains(99.36%)showed PCR positive to tlh, toxR, and tdh but eleven strains were tdh negative. MLST showed that all the 36 O3 : K6 isolates belonged to ST3 and all the 5 O4 : K8 strains were ST189. These results matched the description of the pandemic VP clone.</p><p><b>CONCLUSION</b>A recognizable burden of diarrheal illness caused by VP had been seen in Shenzhen. Results from serotyping indicated that although there existing a large variety of diversities, the dominant serotype appeared to be O3 : K6. VP isolates identified in Shenzhen mainly showed as tdh positive but trh negative, in consistent with the current pandemic O3 : K6 clone. The pandemic O3 : K6 clone did appear to co-exist with other clones of O3 : K6, as well as O4 : K8,O1 : K25. Potential outbreak of VP could be monitored through the laboratory-based surveillance programs, suggesting that the strategies related to prevention and control of VP should be prioritized in Shenzhen.</p>
Asunto(s)
Humanos , China , Epidemiología , Electroforesis en Gel de Campo Pulsado , Tipificación de Secuencias Multilocus , Reacción en Cadena en Tiempo Real de la Polimerasa , Serotipificación , Vibriosis , Epidemiología , Microbiología , Vibrio parahaemolyticus , Genética , VirulenciaRESUMEN
<p><b>OBJECTIVE</b>To determine the expression level of Smad ubiquitination regulatory factor 1 (SMURF1) gene in hepatocellular carcinoma, and to explore its role in liver cancer.</p><p><b>METHODS</b>With non-neoplastic adjacent normal tissues as controls, real-time PCR and Western blotting were used for measuring the expression of SMURF1 mRNA and protein in 89 samples of hepatocellular carcinoma. Correlations between SMURF1 expression and clinical features were explored. Following transfection of SMURF1--specific small interference RNA(siRNA), the apoptosis and proliferation of hepatic cancer cells Hep G2 were detected using flow cytometry and MTT assays .</p><p><b>RESULTS</b>The expression of SMURF1 mRNA and protein were significantly higher in hepatocellular cancer tissues compared with the paired normal tissues (P< 0.05). The expression of SMURF1 however did not correlate with any clinical features (P> 0.05). Transfection of SMURF1-specific siRNA can promote the apoptosis whilst inhibit the proliferation of Hep G2 cells.</p><p><b>CONCLUSION</b>The expression of SMURF1 is enhanced in hepatocellular carcinoma, which may have played a role in the disease through affecting apoptosis and proliferation of hepatic cancer cells.</p>
Asunto(s)
Femenino , Humanos , Masculino , Células Hep G2 , Neoplasias Hepáticas , Patología , ARN Mensajero , Factor de Crecimiento Transformador beta , Fisiología , Ubiquitina-Proteína Ligasas , Genética , FisiologíaRESUMEN
This study was aimed to explore the effect of cordyceps sinensis enhancing lymphocyte proliferation and surface CD marker expression in simulated microgravity environment. The splenic lymphocytes were separated from mice and cultured in the rotary cell culture system simulated microgravity environment. The cells were treated with different concentration of cordyceps sinensis solution (0, 6.25, 12.5, 25 and 50 µg/ml) for 24, 48 and 72 h respectively, then the cells were harvested, and analyzed for cell proliferation and the expression of cell surface markers (CD4 and CD8). The results showed that under simulated microgravity environment, the lymphocyte proliferation was inhibited. When the concentration of cordyceps sinensis was 25 or 50 µg/ml, the lymphocyte proliferation, CD4 and CD8 expressions all increased, but 50 µg/ml cordyceps sinensis could inhibit the proliferation ability with the time prolonging. It is concluded that the suitable concentration of cordyceps sinensis displayed the ability to enhance the lymphocyte proliferation and CD marker expression in simulated microgravity environment. These results may be valuable for screening drugs which can be potentially against immunosuppression under simulated microgravity.
Asunto(s)
Animales , Ratones , Antígenos CD4 , Metabolismo , Antígenos CD8 , Metabolismo , Proliferación Celular , Células Cultivadas , Cordyceps , Tolerancia Inmunológica , Activación de Linfocitos , Linfocitos , Metabolismo , Ratones Endogámicos C57BL , Polisacáridos , Farmacología , Bazo , Biología Celular , Simulación de IngravidezRESUMEN
This study was aimed to evaluate the effect of lentinan on the immune function of splenic lymphocytes in rotary cell culture system (RCCS) microgravity environment. The splenic lymphocytes from mice were separated and cultured in the normal gravity and the microgravity environments. The cells were treated with lentinan solution (0, 10, 20 and 40 µg/ml). After incubated with lentinan for indicated times (24, 48 and 72 h), the cell proliferation, secretion of cytokine and the expression of cell surface markers were detected by MTT method, ELISA and flow cytometry respectively. The results indicated that lentinan of above mentioned concentrations did not obviously promote the lymphocyte proliferation, but increased the secretion of IL-2 and IFN-γ and enhanced the expression of lymphocyte surface markers CD4 and CD8 in microgravity environment. It is concluded that lentinan has the ability to enhance the lymphocyte immune function in microgravity environment.
Asunto(s)
Animales , Ratones , Células Cultivadas , Citocinas , Secreciones Corporales , Tolerancia Inmunológica , Terapia de Inmunosupresión , Lentinano , Farmacología , Activación de Linfocitos , Alergia e Inmunología , Linfocitos , Biología Celular , Alergia e Inmunología , Ratones Endogámicos C57BL , Bazo , Biología Celular , Simulación de IngravidezRESUMEN
<p><b>OBJECTIVE</b>To study the characteristics of the strains of Salmonella enterica (S. enterica) serovar Senftenberg lacking Salmonella pathogenicity island 1 (SPI-1).</p><p><b>METHODS</b>A total of 10 strains of S. enterica serovar Senftenberg were isolated from 10 cases of diarrhea patients. Pulsed field gel electrophoresis (PFGE), PCR, sequencing techniques and cell invasion test were adapted to study the molecular types and invasiveness of the genes and cells; and made a comparison between the 10 strains and the strains (C02013) isolated in Shenzhen in 2002.</p><p><b>RESULTS</b>The 10 Senftenberg isolated (S09007-S09012, S09014-S09017) in Shanghai showed three PFGE patterns, which were significantly different from the strains isolated in Shenzhen. PCR-amplified results indicated the invasion gene (invA), secreted effector protein gene (sipA) and gene fragments as fhlA-hilA, hilA-spaP and spaP-invH in the 10 strains of SPI-1 were all negative. The sequencing results revealed that the 10 strains isolated in Shanghai lacked most parts of SPI-1 genes, as fragments from orgA to invH and parts of orgA gene itself; however, compared with strains isolated in Shenzhen, the sprB-orgC gene existed. The missing parts of genes were replaced by a simple insertion sequence (IS) of 1000 bp in the strains isolated both in Shenzhen in 2002 and in Shanghai in 2006. The invasiveness rates of the 10 strains (S09007-S09012, S09014-S09017) towards Hela cells were (0.0053 ± 0.0024)%, (0.0046 ± 0.0006)%, (0.0047 ± 0.0003)%, (0.0064 ± 0.0012)%, (0.0065 ± 0.0011)%, (0.0070 ± 0.0020)%, (0.0115 ± 0.0030)%, (0.0099 ± 0.0039)%, (0.0180 ± 0.0135)% and (0.0031 ± 0.0012)%, respectively; which were all significantly lower than the rate of invA-positive control strain STM1344 ((5.0800 ± 0.6333)%); lower or close to the rate of invA-lacked artificial-mutated strain STMinvA-((0.0193 ± 0.0045)%).</p><p><b>CONCLUSION</b>SPI-1 genes are not essential for the diarrhea caused by S. enterica serovar Senftenberg.</p>
Asunto(s)
Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Técnicas de Tipificación Bacteriana , Diarrea , Microbiología , Heces , Microbiología , Genes Bacterianos , Islas Genómicas , Células HeLa , Salmonella enterica , Genética , VirulenciaRESUMEN
<p><b>OBJECTIVE</b>To estimate tone-pip auditory brainstem response (tone-pip ABR) and auditory steady-state response (ASSR) thresholds to follow the development of hearing in four groups of normal babies through the first 6 month of life and to make a comparison between the tone-pip ABR and ASSR for 0.25 - 8 kHz frequency range at different groups.</p><p><b>METHODS</b>The tone-pip ABR and ASSR were recorded in four groups of normal hearing infants (160 ears) at the age of 2 - 4 day, 6 weeks, 3-month and 6-month. Tone-pip ABR and ASSR thresholds were established in 0.25, 0.5, 1, 2, 4 and 8 kHz stimuli.</p><p><b>RESULTS</b>For click ABR, the wave latency of I, III, V and inter-wave latency of I-III, III-V and I-V decreased as the age increase. The developmental changes were obvious in wave I and III before 6 weeks and 3 months respectively. Tone-pip ABR had the similar waveform as the click ABR. With the frequency increasing, their waveforms and wave latencies of I, III and V were getting better and shorter respectively. There was significant difference between the thresholds of tone-pip ABR and ASSR (all P < 0.05). The tone-pip ABR thresholds were significantly lower than those of ASSR from 0.5 to 8 kHz. Both ASSR and tone-pip ABR had similar audiograms for different age of infants with normal hearing.</p><p><b>CONCLUSIONS</b>The longitudinal findings presented in this study suggest that with the maturational development, the wave latency of I, III, V and inter-wave latency of I-III, III-V and I-V of tone-pip ABR decrease as the age increase, while the hearing sensitivity have no changes. Both tone-pip ABR and ASSR have stable frequency specificity. Compared to the ASSR, tone-pip ABR have lower response threshold and maybe nearer to the hearing level of the infant.</p>
Asunto(s)
Humanos , Lactante , Umbral Auditivo , Potenciales Evocados Auditivos del Tronco Encefálico , Audición , Pruebas Auditivas , Sensibilidad y EspecificidadRESUMEN
Space flight is known to produce a number of neurological disturbances. The etiology is unknown, but it may involve increased oxidative stress. A line of experimental evidence indicates that space flight may disrupt antioxidant defense system and result in increased oxidative stress. In vitro studies found that abundant of NO was produced in rat pheochromocytoma (PC12) cells, SHSY5Y neuroblastoma cells, and protein nitration was increased in PC12 cells within a simulated microgravity rotating wall bioreactor high aspect ratio vessel system or clinostat system. In the present study, we observed the change of redox status in SH-SY5Y cells after parabolic flight, and studied the effects of key redox molecule, thioredoxin (TRX), during the altered gravity. SH-SY5Y cells were divided into four groups: control cells, control cells transfected with TRX, flight cells and flight cells transfected with TRX. The expression levels of 3-nitrotyrosine (3-NT), inducible nitric oxide synthase (iNOS), TRX and thioredoxin reductase (TRXR) were observed by immunocytochemical method. It was shown that after parabolic flight, the staining of 3-NT and TRX were enhanced, while the expression level of TRXR was down-regulated compared with control. As for flight cells transfected with TRX, the staining of 3-NT and iNOS were weakened compared with flight cells. These results obtained suggest that altered gravity may increase protein nitration, down-regulate TRXR and elicit oxidative stress in SH-SY5Y cells, while TRX transfection could partly protect cells against oxidative stress induced by parabolic flight.
Asunto(s)
Animales , Humanos , Ratas , Antioxidantes , Línea Celular Tumoral , Hipogravedad , Óxido Nítrico Sintasa de Tipo II , Fisiología , Estrés Oxidativo , Células PC12 , Vuelo Espacial , Reductasa de Tiorredoxina-Disulfuro , Fisiología , Tiorredoxinas , Fisiología , Transfección , Tirosina , FisiologíaRESUMEN
Microgravity is known to produce a number of neurological disturbances during space flight; however, the underlying mechanism of these disturbances is yet to be elucidated. There have been some reports about the increased oxidative stress under microgravity or simulated microgravity. In the present study, we investigated the process of oxidative stress induced by simulated microgravity in different areas of rat brain, which may shed light on the mechanism of neurological disturbances and further neuroprotective research in spaceflight. After adaption for 7 d, 40 healthy male Sprague-Dawley rats were matched for body weight and randomly assigned to control groups (7, 14, 21 and 28 d) and tail-suspended simulated microgravity groups (7, 14, 21 and 28 d). The tail-suspended groups were treated with 30 angels of tail suspension and the control groups were treated similarly to the tail-suspended groups but without tail suspension. After the required times, different structures of rat brain, including cerebellum, cerebral cortex and hippocampus, were harvested and frozen for the further determination. Griess assay, thiobarbituric acid reactive substance (TBARS) assay, competitive ELISA and ferric reducing ability of plasma (FRAP) assay were used for the observation of the changes of reactive nitrogen species (RNS), malondialdehyde (MDA), nitrotyrosine (NT) and total antioxidant capacity (TAC), respectively. As shown in the results, there were different changes in various brain regions after tail suspension compared with control groups. (1) In cerebellum, NT increased after 7 d tail suspension, decreased after 14 d and increased again after 28 d; MDA increased after 14 d; RNS increased and TAC decreased after tail suspension for 21 d; (2) Increase of NT after14 d tail suspension, increase of MDA and decrease of TAC after 21 d were found in cerebral cortex; (3) In hippocampus, RNS increased after tail suspension for 7 d, decreased after 14 d and increased again after 28 d; MDA increased after 21 d; NT increased after 28 d; TAC increased after 7 d and recovered after 21 d. These results suggest that simulated microgravity induced by tail suspension increases the level of oxidative stress in rat brain; however, there are different features in different areas of rat brain. During the response to simulated microgravity, rat brain tissues present a similar process from adaptive response to irreversible oxidative damage.
Asunto(s)
Animales , Masculino , Ratas , Antioxidantes , Metabolismo , Encéfalo , Suspensión Trasera , Malondialdehído , Metabolismo , Estrés Oxidativo , Ratas Sprague-Dawley , Simulación de IngravidezRESUMEN
Objective To study the role of neuronal nitric oxide synthase (nNOS) in ischemicpreconditioning and its mechanism in a cell model transiently exposed to COCl2 for mimicking ischemicpreconditioning. Methods SK-N-SH cells were pretreated with 300 μmol/L COCl2 for 3 h andcultured 24 h later in serum-free media to establish the cell model ofischemic preconditioning. 7-NI, aspecific inhibitor of nNOS, was used to explore the role ofnNOS in the preconditioning process. MTTassay and flow cytometry (FAM) were used to detect the cell proliferation and apoptosis, respectively, atdifferent time points after the preconditioning. Reverse transcriptase-polymerase chain reaction (RT-PCR)was performed to detect the expression levels of nNOS and the apoptosis-related genes after ischemicpreconditioning. Results In serum-flee culture after exposure to 300 μmol/L COCl2, the SK-N-SHcells showed an increase in cell proliferation by 2.5 folds and a reduction of the cell apoptotic rate by70%, with significant differences from the control cells (P<0.05). At 3 and 24 h after ischemicpreconditioning, the expression of nNOS and Bcl-2, an apoptosis suppressor gene, was up-regnlated andthe expression of Apaf-1, an apoptosis-promoting gene, was down-regnlated. These effects could bereversed by 7-NI, an inhibitor ofnNOS. Conclusion Pretreatment with 300 μmol/L COCl2 for 3 h canmimic ischemic preconditioning in SK-N-SH cells, in which process nNOS plays an important protectiverole by regulating the expression of Bcl-2 and Apaf-1.
RESUMEN
<p><b>OBJECTIVE</b>To investigate the role of Ca(2+)/calmodulin-dependent calcineurin (CaN) signaling pathway in neuropeptide Y (NPY)-induced cardiomyocyte hypertrophy in rat.</p><p><b>METHODS</b>Cardiomyocytes of neonatal Wistar rats were cultured in the presence of 10 and 100 nmol/L NPY, and cyclosporine A (CsA) was applied to inhibit the activity of CaN. The protein synthesis rate, c-jun mRNA expression, CaN protein expression, CaN activity and intracellular Ca(2+) concentration in the cardiomyocytes were assessed.</p><p><b>RESULTS</b>Compared with the control group, (3)H-Leu incorporation and expression of c-jun mRNA in the cardiomyocytes treated with 100 nmol/L NPY increased significantly (P<0.05, P<0.001), and the effect of NPY was blocked by CsA. The activity of CaN (P<0.05), CaN expression (P<0.05), and Ca(2+) concentration in the cytoplasm (P<0.001) and nuclei (P<0.001) of the cells with 100 nmol/L NPY treatment also significantly increased compared with those in the control cells.</p><p><b>CONCLUSION</b>NPY can induce cardiomyocyte hypertrophy in rats, in which process Ca(2+)/calmodulin-dependent CaN signaling pathway plays an important role.</p>