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1.
Biochem Genet ; 60(6): 1881-1894, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35122557

RESUMEN

Unique anatomical and physiological features have made hamster species desirable research models. Comparative genomics and phylogenetic analysis of the hamster family members to clarify their evolution and genetic relationship, can provide a genetic basis for the comprehension of the variable research results obtained using different hamster models. The Syrian golden hamster (Mesocricetus auratus) is the most widely used species. In this study, we sequenced the complete mitochondrial genome (mitogenome) of M. auratus, compared it with the mitogenome of other Cricetinae subfamily species, and defined its phylogenetic position in the Cricetidae family. Our results show that the mitogenome organization, gene arrangement, base composition, and genetic analysis of the protein coding genes (PCGs) of M. auratus are similar to those observed in previous reports on Cricetinae species. Nonetheless, our analysis clarifies some striking differences of M. auratus relative to other subfamily members, namely distinct codon usage frequency of TAT (Tyr), AAT (Asn), and GAA (Glu) and the presence of the conserved sequence block 3 (CSB-3) in the control region of M. auratus mitogenome and other hamsters (not found in Arvicolinae). These results suggest the particularity of amino acid codon usage bias of M. auratus and special regulatory signals for the heavy strand replication in Cricetinae. Additionally, Bayesian inference/maximum likelihood (BI/ML) tree shows that Cricetinae and Arvicolinae are sister taxa sharing a common ancestor, and Neotominae split prior to the split between Cricetinae and Arvicolinae. Our results support taxonomy revisions in Cricetulus kamensis and Cricetulus migratorius, and further revision is needed within the other two subfamilies. Among the hamster research models, Cricetulus griseus is the species with highest sequence similarity and closer genetic relationship with M. auratus. Our results show mitochondrial DNA diversity of M. auratus and other Cricetinae species and provide genetic basis for judgement of different hamster models, promoting the development and usage of hamsters with regional characteristics.


Asunto(s)
Arvicolinae , ADN Mitocondrial , Cricetinae , Animales , Mesocricetus , ADN Mitocondrial/genética , Cricetulus , Arvicolinae/genética , Filogenia , Teorema de Bayes
2.
Artículo en Inglés | MEDLINE | ID: mdl-38277247

RESUMEN

The absolute positioning accuracy of an industrial robot arm is vital for advancing manufacturing-related applications like automatic assembly, which can be improved via the data-driven approaches to robot arm calibration. Existing data-driven calibrators have illustrated their efficiency in addressing the issue of robot arm calibration. However, they mostly are single learning models that can be easily affected by the insufficient representation of the solution space, therefore, suffering from the calibration accuracy loss. To address this issue, this study proposes a calibrator fuzzy ensemble (CFE) with twofold ideas: 1) implementing eight data-driven calibrators relying on different sophisticated machine learning algorithms for an industrial robot arm, which guarantees the accuracy of individual base models and 2) innovatively developing a fuzzy ensemble of the obtained eight diversified calibrators to obtain impressively high calibration accuracy for an industrial robot arm. Extensive experiments on an ABB IRB120 industrial robot implemented with MATLAB demonstrate that compared with state-of-the-art calibrators, CFE decreases the maximum error at 8.59%. Hence, it has great potential for real applications.

3.
EClinicalMedicine ; 72: 102623, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38800802

RESUMEN

Background: In ORIENT-15 study, sintilimab plus chemotherapy demonstrated significant improvement on overall survival (OS) versus placebo plus chemotherapy in first-line treatment of advanced esophageal squamous cell carcinoma (ESCC). Here, we report effect of sintilimab plus chemotherapy on health-related quality of life (HRQoL) in patients with advanced ESCC. Methods: From December 14, 2018 to August 28, 2022, HRQoL was evaluated in all randomized patients using European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 items (QLQ-C30), EORTC Quality of Life Questionnaire Oesophageal Cancer Module 18 items (QLQ-OES18), and visual analogue scale (VAS) of the EuroQol five-dimensional five-level questionnaire (EQ-5D-5L). Mean scores of each scale were described by treatment group through week 60. Least-squares mean (LSM) score change from baseline through week 24 were analyzed using the mixed-model repeated-measures method. Time to the first onset of deterioration (TTD) and OS for each scale were estimated. Clinical Trials Registration: NCT03748134. Findings: As of August 28, 2022, 689 of 690 enrolled patients were assessed for HRQoL analysis (sintilimab group: 340, placebo group: 349). Median follow-up was 32.2 months. Differences in LSM favored sintilimab over placebo for QLQ-C30 social functioning (LSM difference: 3.06, 95% CI: 0.55 to 5.57; P = 0.0170), pain (-2.24, 95% CI: -4.30 to -0.17; P = 0.0337), fatigue (-2.24, 95% CI: -4.46 to -0.02; P = 0.0479), constipation (-3.27, 95% CI -5.49 to -1.05; P = 0.0039), QLQ-OES18 pain (-1.77, 95% CI -3.11 to -0.43; P = 0.0097), trouble swallowing saliva (-2.09, 95% CI: -3.77 to -0.42; P = 0.0146), and choked when swallowing (-3.23, 95% CI: -5.60 to -0.86; P = 0.0076). TTD favored sintilimab over placebo for QLQ-OES18 dysphagia (Hazard ratio [HR]: 0.76, 95% CI: 0.61-0.94, P = 0.0104), and trouble swallowing saliva (HR: 0.48, 95% CI: 0.35-0.67, P < 0.0001). Improved OS were observed in patients with better performance in several functioning and symptom scales of QLQ-C30 and QLQ-QES18. Interpretation: The statistically significant differences of several HRQoL scales and improvements in delayed deterioration observed in our study further support the use of sintilimab plus chemotherapy as first-line treatment for advanced ESCC. Funding: This study was funded by Innovent Biologics and was co-funded by Eli Lilly.

4.
ISA Trans ; 127: 120-132, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35304004

RESUMEN

This paper addresses a secure predictor-based neural dynamic surface control (SPNDSC) issue for a cyber-physical system in a nontriangular form suffering from both sensor and actuator deception attacks. To avoid the algebraic loop problem, only partial states are employed as input vectors of neural networks (NNs) for approximating unknown dynamics, and compensation terms are further developed to offset approximation errors from NNs. With introduction of nonlinear gain functions and attack compensators, adverse effects of an intelligent adversary are alleviated effectively. Furthermore, we present stability analysis and prove the ultimate boundedness of all signals in the closed-loop system. The effectiveness of the proposed control strategy is illustrated by two examples.


Asunto(s)
Redes Neurales de la Computación , Dinámicas no Lineales , Simulación por Computador , Equipo Médico Durable , Retroalimentación
5.
Innovation (Camb) ; 3(3): 100239, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35509869

RESUMEN

Lack of effective targeted therapy in metastatic esophageal squamous cell carcinoma (ESCC) underscores the urgent need for identifying new treatment approaches for this challenging disease. We sought to assess the addition of cetuximab to paclitaxel-cisplatin chemotherapy for first-line treatment in patients with metastatic ESCC. In this randomized, multicenter, open-label, phase II clinical trial, patients were randomized to receive paclitaxel-cisplatin (TP) (paclitaxel [175 mg/m2 intravenously (i.v.) on day 1 of every 3-week cycle] and cisplatin [75 mg/m2 i.v. on day 1 of every 3-week cycle]) and TP plus cetuximab (CTP) (cetuximab, 400 mg/m2 i.v. on day 1 of week 1, followed by 250 mg/m2 weekly), respectively. Targeted next-generation sequencing (NGS) was performed on 89 tumor samples for biomarker exploration. The primary endpoint was progression-free survival (PFS) in the intention-to-treat population. With a median follow-up of 22.6 months, median PFS was 5.7 months (95% confidence interval [CI]: 4.8-7.0) in patients administered CTP versus 4.2 months (95% CI: 3.0-5.3) in the TP group (hazard ratio [HR] = 0.61; 95% CI: 0.40-0.93; p = 0.02). Median overall survival was 11.5 months (95% CI: 7.9-13.1) in the CTP group and 10.5 months (95% CI: 9.0-13.2) in the TP arm (HR = 0.98; 95% CI: 0.67-1.44; p = 0.91). The most common reported greater than or equal to grade 3 adverse events were neutropenia (35.2% versus 22.4%) and leukopenia (25.4% versus 13.2%). In patients with epidermal growth factor receptor (EGFR) amplification tumors (15.7%), PFS was improved with CTP compared with TP treatment (HR = 0.11; 95% CI: 0.01-0.98; p = 0.018). First-line CTP significantly improves PFS, with a manageable safety profile in patients with metastatic ESCC.

6.
BMJ ; 377: e068714, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-35440464

RESUMEN

OBJECTIVE: To evaluate sintilimab versus placebo in combination with chemotherapy (cisplatin plus paclitaxel or cisplatin plus 5-fluorouracil) as first line treatment of unresectable locally advanced, recurrent, or metastatic oesophageal squamous cell carcinoma. DESIGN: Multicentre, randomised, double blind, phase 3 trial. SETTING: 66 sites in China and 13 sites outside of China between 14 December 2018 and 9 April 2021. PARTICIPANTS: 659 adults (aged ≥18 years) with advanced or metastatic oesophageal squamous cell carcinoma who had not received systemic treatment. INTERVENTION: Participants were randomised 1:1 to receive sintilimab or placebo (3 mg/kg in patients weighing <60 kg or 200 mg in patients weighing ≥60 kg) in combination with cisplatin 75 mg/m2 plus paclitaxel 175 mg/m2 every three weeks. The trial was amended to allow investigators to choose the chemotherapy regimen: cisplatin plus paclitaxel or cisplatin plus 5-fluorouracil (800 mg/m2 continuous infusion on days 1-5). MAIN OUTCOME MEASURES: Overall survival in all patients and in patients with combined positive scores of ≥10 for expression of programmed cell death ligand 1. RESULTS: 659 patients were randomly assigned to sintilimab (n=327) or placebo (n=332) with chemotherapy. 616 of 659 patients (93%) received sintilimab or placebo in combination with cisplatin plus paclitaxel and 43 of 659 patients (7%) received sintilimab or placebo in combination with cisplatin plus 5-fluorouracil. At the interim analysis, sintilimab with chemotherapy showed better overall survival compared with placebo and chemotherapy in all patients (median 16.7 v 12.5 months, hazard ratio 0.63, 95% confidence interval 0.51 to 0.78, P<0.001) and in patients with combined positive scores of ≥10 (17.2 v 13.6 months, 0.64, 0.48 to 0.85, P=0.002). Sintilimab and chemotherapy significantly improved progression free survival compared with placebo and chemotherapy in all patients (7.2 v 5.7 months, 0.56, 0.46 to 0.68, P<0.001) and in patients with combined positive scores of ≥10 (8.3 v 6.4 months, 0.58, 0.45 to 0.75, P<0.001). Adverse events related to treatment occurred in 321 of 327 patients (98%) in the sintilimab-chemotherapy group versus 326 of 332 (98%) patients in the placebo-chemotherapy group. Rates of adverse events related to treatment, grade ≥3, were 60% (196/327) and 55% (181/332) in the sintilimab-chemotherapy and placebo-chemotherapy groups, respectively. CONCLUSIONS: Compared with placebo, sintilimab in combination with cisplatin plus paclitaxel showed significant benefits in overall survival and progression free survival as first line treatment in patients with advanced or metastatic oesophageal squamous cell carcinoma. Similar benefits of sintilimab with cisplatin plus 5-fluorouracil seem promising. TRIAL REGISTRATION: ClinicalTrials.gov NCT03748134.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Adolescente , Adulto , Anticuerpos Monoclonales Humanizados/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Cisplatino/uso terapéutico , Método Doble Ciego , Neoplasias Esofágicas/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Fluorouracilo/uso terapéutico , Humanos , Paclitaxel/uso terapéutico
7.
Avian Dis ; 55(3): 451-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22017046

RESUMEN

Between 2006 and 2009, seven strains of infectious bronchitis (IB) virus (IBV) were isolated from vaccinated chicken flocks on different chicken farms in China. The pathogenic characters of seven IBV strains were assessed. Each of the seven strains was infective to the test chickens and could induce an immune response. The results from chicken embryo cross-neutralization assays showed that these strains were antigenically distinct from classic IBV strains of H120, M41, Conn, and Gray. Compared to H120 vaccine strain, point mutation, short insertion, and deletion occurred at many positions in the S1 protein of the seven strains. Five of the seven strains had the motif (HRRRR), which was identical to that of the epidemic IBV strains in China. Two new motifs (HRLRR and RRIRR) emerged in the isolated strains. The homology of the nucleotide and amino acid sequences of the S1 gene among the seven isolates was 81.7%-99.7% and 79.0%-99.4%, respectively. These seven strains were also genetically different from the vaccine strains and non-China IBV strains but closely related to large numbers of Chinese strains. The seven isolates and 36 reference IBV strains were clustered into six distinct groups (I-VI). The seven strains were categorized into groups I, II, and III, forming a big phylogenetic branch, which is closely related to Chinese IBVs, whereas the vaccine strains belonging to group VI are genetically distant from groups I, II, and III. The results from this study indicate that different IBV strains cocirculate in the chicken population in China.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Virus de la Bronquitis Infecciosa/genética , Virus de la Bronquitis Infecciosa/aislamiento & purificación , Glicoproteínas de Membrana/genética , Enfermedades de las Aves de Corral/virología , Proteínas del Envoltorio Viral/genética , Animales , Secuencia de Bases , Embrión de Pollo , Pollos , China/epidemiología , Clonación Molecular , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/genética , Infecciones por Coronavirus/virología , Virus de la Bronquitis Infecciosa/clasificación , Virus de la Bronquitis Infecciosa/inmunología , Filogenia , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Análisis de Secuencia , Glicoproteína de la Espiga del Coronavirus , Vacunas Virales/inmunología
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(5): 1243-7, 2010 May.
Artículo en Zh | MEDLINE | ID: mdl-20672610

RESUMEN

The near infrared reflectance spectroscopy technique (NIRS) has been explored at many fields such as agriculture, food, chemical, medicine, and so on, due to its rapid, effective, non-destructive, and on-line characteristics. Fungi invasion in forage materials during processing and storage would generate mycotoxins, which were harmful for people and animal through food chains. The determination of mycotoxins included the overelaborated pretreatments such as milling, extracting, chromatography and subsequent process such as enzyme linked immunosorbent assay, high performance liquid chromatography, and thin layer chromatography. The authors hope that high precision and low detection limit spectrum instrument, and software technology and calibration model of mycotoxins determination, will fast measure accurately the quality and quantity of mycotoxins, which will provide basis for reasonable process and utilization of forage and promote the application of NIRS in the safety livestock product.


Asunto(s)
Alimentación Animal/análisis , Micotoxinas/análisis , Espectroscopía Infrarroja Corta , Agricultura , Alimentación Animal/microbiología , Animales , Calibración , Cromatografía Líquida de Alta Presión , Programas Informáticos
9.
IEEE Trans Cybern ; 50(12): 5010-5020, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30872247

RESUMEN

This paper addresses an adaptive event-triggered consensus control problem for a class of second-order nonlinear multiagent systems (MASs) in an undirected communication topology. A novel adaptive distributed event-triggered consensus control scheme is presented for the MAS with unknown functions based on the definition of an auxiliary state, and the coefficient of the triggered function can be regulated adaptively with dependence on the auxiliary state error to ensure not only the control performance but also the efficiency of the network interactions. Furthermore, two self-triggered algorithms are developed for two cases, known functions and unknown ones, by the current state and information at the previous event time instant instead of the requirement for continuous monitoring auxiliary state errors. In theory, the stability of the resulting closed-loop system is rigorously investigated, and it is proven that all signals in the closed-loop system are bounded and the Zeno behavior is ruled out. Finally, two simulation examples, both real-time and numerical ones, are provided to verify the theoretical claims.

10.
Anim Reprod Sci ; 105(3-4): 398-403, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18096334

RESUMEN

The objective of this study was to obtain a fast, accurate and reliable method of determining the sex of goat embryos prior to implantation through amplification of the high-motility-group (HMG) box of the sex-determining region of the Y chromosome (SRY) gene of the goats. Goat specific primers were designed for duplex polymerase chain reaction (PCR). As an internal control gene, the goat beta-action gene sequence was simultaneously amplified together with the HMG box of goat SRY gene. Males showed both 1 SRY band and 1 beta-action band, but only 1 beta-action band was present in the agarose gel electrophoresis of females. The result indicated that the goat HMG-box sequence motif of SRY was male specific. Afterward, the optimized PCR procedure was applied in 30 embryo biopsies and the biopsied embryos were transferred into 30 recipient female goats. The sex of the 13 kids proved anatomically corresponded to the sex determined by PCR (100% accuracy). Thus, this study showed that this duplex PCR method can be applied to sex the goat pre-implantation embryos and to manipulate the sex ratio of offspring in goat breeding programs.


Asunto(s)
Cabras/embriología , Dominios HMG-Box , Análisis para Determinación del Sexo/veterinaria , Animales , Animales Recién Nacidos , ADN/química , ADN/genética , Electroforesis en Gel de Agar/veterinaria , Transferencia de Embrión/veterinaria , Femenino , Genes sry , Cabras/genética , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Análisis para Determinación del Sexo/métodos
11.
Theriogenology ; 114: 95-102, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29605576

RESUMEN

To investigate the effects of maternal dietary selenium (Se-enriched yeast) on testis development, testosterone level and steroidogenesis-related gene expression in testis of their male kids, selected pregnant Taihang Black Goats were randomly allotted to four treatment groups. They were fed the basal gestation and lactation diets supplemented with 0 (control), 0.5, 2.0 and 4.0 mg of Se/kg DM. Thirty days after weaning, testes were collected from the kids. After the morphological development status of testis was examined, tissue samples were collected for analyzing testosterone concentration and histological parameters. Testosterone synthesis-related genes were detected using real-time PCR. Localization and quantification of androgen receptor (AR) in testis of goats were determined by immunohistochemical and western blot analysis. The results show that Se supplementation in the diet of dams led to higher (p < 0.05) testicular weight, volume, length, width, transverse and vertical grith of their male kids. Excessive Se (4.0 mg/kg) can inhibit the development of testis by decreasing testicular weight and volume. The density of spermatogenic cells and Leydig cells in the Se treatment groups was significantly (p < 0.05) higher than that in the control. Maternal dietary Se did not affect the thickness of testes, thickness of germinal epithelium and diameter of seminiferous tubule. Se supplemented in the diet of dams improved the testosterone level in testis tissue and serum, and promote the expression of testosterone-related genes. The mRNA expression of StAR, 3ß-HSD and CYP11A1 was decreased with the increasing dietary Se levels of dams. Maternal dietary Se can improve the AR protein abundance in testis of their offspring. AR immunopositive product was detected in Leydig cells, peritubular myoid cells, perivascular smooth muscle cells, primary spermatocytes and spermatids. The expression of AR in spermatogenetic cells is stage specific. This study suggests that maternal dietary Se can influence the testis development and spermatogenesis of their male kids by modulating testosterone synthesis in goats. More attention should be given to the potential role of maternal nutrition in improving reproductive performance of their offspring.


Asunto(s)
Dieta/veterinaria , Fenómenos Fisiologicos de la Nutrición Prenatal , Selenio/administración & dosificación , Esteroides/metabolismo , Testículo/crecimiento & desarrollo , Testosterona/sangre , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Suplementos Dietéticos , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Lactancia , Masculino , Embarazo , Maduración Sexual , Testículo/efectos de los fármacos
12.
Yi Chuan ; 29(3): 313-8, 2007 Mar.
Artículo en Zh | MEDLINE | ID: mdl-17369152

RESUMEN

A 261 bp sequence of the bovine MyoD gene intron 2 was cloned and was found to bear no similarities to the human MyoD gene sequence. Polymorphisms of the Myod gene in cattle including three Chinese breeds (Luxi cattle, Jinnan cattle and Qinchuan cattle) and four cross-breeding populations (Limousin x Luxi cattle, Simmental x Luxi cattle, Charolais x Luxi cattle and Angus x Luxi cattle) were detected by PCR-SSCP. Two SSCP alleles (A and B) were detected, which caused by a C-->T at 39 bp and a C-->G transition at 112 bp. Only two genotypes AA and AB occurred in the population. In Chinese local cattle, B allele was dominant, and this locus was at Hardy-Weinberg equilibrium except for the Charolais x Luxi cattle and Angus x Luxi cattle. The association of these polymorphisms with cattle carcass traits was analyzed using the general linear model (GLM). Statistical analysis revealed a higher value of living weight, carcass weight and loin eye area for individuals with genotype AA than AB (P < 0.05). Further studies on a bigger population size are needed to confirm the observed effect of MyoD genotypes on carcass quality traits.


Asunto(s)
Ligamiento Genético , Proteína MioD/genética , Polimorfismo Genético , Alelos , Animales , Bovinos , Femenino , Frecuencia de los Genes , Genotipo , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple
13.
Theriogenology ; 83(1): 30-7, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25277529

RESUMEN

Follicular fluid meiosis-activating sterol (FF-MAS), an intermediate in the cholesterol biosynthetic pathway, has been identified as a compound that induces the resumption of meiosis in mammalian oocyte. Follicular fluid meiosis-activating sterol is converted to testis meiosis-activating sterol by a sterol Δ14-reductase. An inhibitor of Δ14-reductase and Δ7-reductase, AY9944 A-7, causes accumulation of FF-MAS by inhibiting its metabolism. The objective of this research was to investigate the specific contribution of AY9944 A-7 on gonadotropin-induced meiotic resumption and its interactive effects with FSH or LH on meiotic maturation of oocytes and preimplantation development of parthenogenetic embryo in sheep by addition of AY9944 A-7 during IVM to cause accumulation of FF-MAS. First, ovine cumulus-oocyte complexes (COCs) were cultured in the presence of FSH (10 µg/mL), LH (10 µg/mL), AY9944 A-7 (20 µmol/L), FSH (10 µg/mL)+AY9944 A-7 (20 µmol/L), or LH (10 µg/ml) + AY9944 A-7 (20 µmol/L) with an inhibitor hypoxanthine (Hx) to prevent spontaneous meiosis of oocytes. The resumption of meiosis was assessed by the frequency of germinal vesicle breakdown and the first polar body (PBI) extrusion. The kinetics of gonadotropin and AY9944 A-7-induced meiotic resumption in vitro was also evaluated in the study. The numbers of oocytes resuming meiosis and undergoing germinal vesicle breakdown were counted after the COCs were cultured for 2, 4, 8, 12, 16, 20, and 24 hours. Matured oocytes extruding PBI were selected for parthenogenetic activation, and the percentages developing to the two-cell stage and blastocyst stage were recorded as indicators of parthenogenetic embryo developmental competence. It was observed that FSH could induce the resumption of meiosis of ovine COCs cultured in the presence of Hx, but LH could not. AY9944 A-7 had a synergistic effect with FSH on nuclear maturation and developmental competence of embryos produced by parthenogenetic activation, whereas it had no added advantage on LH action. However, the kinetics of meiotic resumption after AY9944 A-7 stimulation was remarkably delayed when compared with FSH-induced maturation. In conclusion, the current study suggested that AY9944 A-7 supplementation in IVM medium optimized the beneficial effects of FSH on meiotic maturation of ovine oocytes and subsequent developmental competence of embryos produced by parthenogenetic activation. This work had important potential for developing a novel technique in IVM of ovine oocytes.


Asunto(s)
Desarrollo Embrionario/efectos de los fármacos , Gonadotropinas/farmacología , Meiosis/efectos de los fármacos , Oocitos/efectos de los fármacos , Partenogénesis/fisiología , Ovinos/embriología , Diclorhidrato de trans-1,4-Bis(2-clorobenzaminometil)ciclohexano/farmacología , Animales , Interacciones Farmacológicas , Técnicas de Cultivo de Embriones/veterinaria , Femenino , Hormona Folículo Estimulante/farmacocinética , Hormona Folículo Estimulante/farmacología , Técnicas de Maduración In Vitro de los Oocitos/métodos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Hormona Luteinizante/farmacocinética , Hormona Luteinizante/farmacología , Meiosis/fisiología , Oocitos/citología , Oocitos/fisiología , Oxidorreductasas/antagonistas & inhibidores , Factores de Tiempo
14.
Anim Reprod Sci ; 149(3-4): 266-72, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25115807

RESUMEN

The objective of this study was to investigate the different levels of dietary Se (from sodium selenite) on the proliferation of SSCs (spermatogonial stem cells) in testis of roosters. Also, the antioxidant status and Se content in blood plasma and testis were evaluated. A total of eighty 12-week-old Hy-Line Variety white roosters at an averaged body weight of 1.38 ± 0.2 kg were selected and randomly divided into four experimental groups. They were fed with the basal diet (0.044 mgSe/kg DM) supplemented with 0 (control), 0.5, 1.0 or 2.0 mgSe/kg DM (from sodium selenite). After the feeding experiment, blood and testis samples were collected for analysis of the antioxidant status and Se concentration. The testis samples were also used to examine the Thy-1 and ß1-integrin mRNA expression by RT-PCR and detect the population of SSCs by immunofluorescence analysis. The results show that Se concentration in blood and testis of the animals was progressively increased with the increasing Se level in diet. The highest GSH-Px (glutathione peroxidase) activity and lowest MDA content in blood and testis was obtained in the treatment of 0.5mg/kg. RT-PCR analysis showed that mRNA expression of SSCs markers were significantly lower in the control and 1.0mg/kg groups when compared with that in the treatment of 0.5mg/kg. A similar trend was observed in the population of SSCs analyzed by immunofluorescence assay. These data suggest that dietary Se can influence the population of SSCs of roosters during spermatogenesis and that oxidative stress can modulate SSCs behavior through regulating some key factors during spermatogenesis.


Asunto(s)
Antioxidantes/metabolismo , Pollos/fisiología , Selenito de Sodio/farmacología , Espermatogonias/citología , Células Madre/efectos de los fármacos , Testículo/efectos de los fármacos , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Proliferación Celular , Dieta/veterinaria , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Masculino , Selenito de Sodio/administración & dosificación , Espermatogonias/fisiología , Células Madre/fisiología , Testículo/fisiología
15.
Int J Clin Exp Med ; 7(12): 5675-80, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25664089

RESUMEN

Helicobacter pylori (Hp) infection is known to alter levels of pepsinogens (PG) and is correlated with several disease states, including gastric and cardiovascular diseases. This study sought to assess whether Hp infection is associated with hypertension as well as to identify the value of assessing the PG I/PG II ratio in patients with hypertension. The study included 396 individuals with hypertension who were assessed for infection with Hp by colloidal gold assay. Participants' weight, height, blood pressure, and serum lipids were measured, and participants were examined for the presence of renal or ocular damage. H. pylori infection status or PG I/PG II ratio were compared against other variables (e.g., body mass index, serum cholesterol, diastolic blood pressure) by t-test or ⇨(2) test, and Pearson's correlation analysis was used to identify associations. Consistent with other studies, the PG I/PG II ratio of patients with Hp infection was significantly lower than that of patients without Hp infection (P < 0.001). The serum total cholesterol and triglycerides of patients with Hp infection were significantly higher than those of patients without Hp infection (P < 0.001), and the PG I/PG II ratio was negatively correlated with total cholesterol (r=-0.61) and triglycerides (r=-0.56) levels. However, there was no significant difference in hypertension severity by Hp infection status or PG I/PG II ratio. Interestingly, the PG I/PG II ratio was significantly lower in patients with hypertensive nephropathy or hypertensive retinopathy than in patients without these symptoms (P < 0.05). The areas under the receiver-operating characteristic curve were 0.77 and 0.83 in the diagnosis of nephropathy and retinopathy, respectively. These findings indicate that the PG I/PG II ratio is lower in individuals with hypertensive nephropathy and hypertensive retinopathy. Thus, the detection of the PG I/PG II ratio may be valuable for diagnostic screening for hypertensive organ damage.

16.
Micron ; 57: 6-12, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24268840

RESUMEN

Supercooling sperm in liquid nitrogen vapour is a feasible and economic technique for the practical production. The study aimed to reveal the negative effects of this rapid freezing and thawing processes on Taihang black goat spermatozoa and to find out the changing of spermatozoa motility and ultrastructure by using CASA and TEM. Qualified semen samples, which collected from twenty Chinese Taihang black goats using artificial vagina were pooled and investigated the kinematics parameters and ultrastructural morphology. The results showed that freezing-thawing caused a significant reduction in the spermatozoon total motility (P<0.001), in rapid and medium cell numbers (P<0.001) and motility parameters (VAP, VSL, VCL, ALH and BCF) (P<0.01). Immotile spermatozoa number was increased significantly after freezing-thawing (P<0.001). In the ultrastructural analysis, the shape with a sperm nucleus characterized by ruptures, bend and deformity was observed. The plasma membranes were broken, and nucleoplasm erupted. The mitochondria in the middle piece were disturbed by partial absence or additional accumulations. Swelling, coiling, vacuolization and structural disorganization of mitochondria were also observed. In conclusion, Freezing-thawing procedure has a detrimental effect on motility, membrane integrity and mitochondria of goat spermatozoa. Transmission electron microscopy provides an intuitive observation to investigate deformity spermatozoa.


Asunto(s)
Criopreservación/veterinaria , Congelación/efectos adversos , Motilidad Espermática/fisiología , Espermatozoides/fisiología , Espermatozoides/ultraestructura , Animales , Membrana Celular/patología , Criopreservación/métodos , Cabras , Calefacción/efectos adversos , Masculino , Microscopía Electrónica de Transmisión , Mitocondrias/patología
17.
PLoS One ; 9(3): e90438, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24595008

RESUMEN

BACKGROUND: The human major histocompatibility complex (MHC) is the most important region in vertebrate genome, and is crucial in innate immunity. Recent studies have demonstrated the possible role of polymorphisms in the MHC region to high risk for esophageal squamous cell carcinoma (ESCC). Our previous genome-wide association study (GWAS) has indicated that the MHC region may confer important risk loci for ESCC, but without further fine mapping. The aim of this study is to further identify the risk loci in the MHC region for ESCC in Chinese population. METHODS: Conditional logistic regression analysis (CLRA) was performed on 24 single nucleotide polymorphisms (SNPs) within the MHC region, which were obtained from the genetically matched 937 cases and 692 controls of Chinese Han population. The identified promising SNPs were further correlated with clinical and clinicopathology characteristics. Immunohistochemistry was performed to explore the protein expression pattern of the related genes in ESCC and neighboring normal tissues. RESULTS: Of the 24 promising SNPs analyzed, we identified three independent SNPs in the MHC region associated with ESCC: rs35399661 (P = 6.07E-06, OR = 1.71, 95%CI = 1.36-2.17), rs3763338 (P = 1.62E-05, OR = 0.63, 95%CI = 0.50-0.78) and rs2844695 (P = 7.60E-05, OR = 0.74, 95%CI = 0.64-0.86). These three SNPs were located at the genes of HLA-DQA1, TRIM27, and DPCR1, respectively. Further analyses showed that rs2844695 was preferentially associated with younger ESCC cases (P = 0.009). The positive immunostaining rates both for HLA-DQA1 and TRIM27 were much higher in ESCC tissues than in neighboring normal tissues (69.4% vs. 26.8% for HLA-DQA1 and 77.6% vs. 47.8% for TRIM27, P<0.001). Furthermore, the overexpression of HLA-DQA1 is correlated significantly with age (P = 0.001) and family history (P<0.001). CONCLUSION: This study for the first time provides evidence that multiple genetic factors within the MHC region confer risk to ESCC on the subjects from high-risk area in northern China.


Asunto(s)
Carcinoma de Células Escamosas/epidemiología , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/epidemiología , Neoplasias Esofágicas/genética , Predisposición Genética a la Enfermedad , Complejo Mayor de Histocompatibilidad/genética , Polimorfismo de Nucleótido Simple/genética , Carcinoma de Células Escamosas/patología , China/epidemiología , Proteínas de Unión al ADN/genética , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Técnicas de Genotipaje , Cadenas alfa de HLA-DQ/genética , Humanos , Inmunohistoquímica , Incidencia , Desequilibrio de Ligamiento/genética , Modelos Logísticos , Proteínas Nucleares/genética , Control de Calidad , Factores de Riesgo
18.
Theriogenology ; 80(5): 436-42, 2013 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-23746691

RESUMEN

Follicular fluid meiosis-activating sterol (FF-MAS), an intermediate in the cholesterol biosynthetic pathway, has been identified as a compound that induces the resumption of meiosis in mammalian oocyte. FF-MAS is converted to testis meiosis-activating sterol by a sterol Δ14-reductase. An inhibitor of Δ14-reductase and Δ7-reductase, AY9944 A-7, causes accumulation of FF-MAS by inhibiting its metabolism. The objective of this study was to determine the effects of AY9944 A-7 supplementation to oocyte maturation media on prepubertal sheep oocyte meiotic resumption and subsequent preimplantation development of embryos. Prepubertal sheep oocytes isolated at the germinal vesicle stage from their follicles were cultured with 0, 10, 20, 30, and 40 µM AY9944 A-7 for 24 hours in media with or without a meiotic inhibitor hypoxanthine (Hx, 4 mM). The resumption of meiosis was assessed by the frequency of germinal vesicle breakdown and the first polar body (PBI) extrusion. After maturation for 24 hours, oocytes with PBI were inseminated in vitro, and the percentages developing to the two-cell stage and blastocyst stage were measured as indicators of early embryonic developmental competence. AY9944 A-7 induced maturation of sheep cumulus-oocyte complexes with optimal concentrations of 10 and 20 µM both in Hx-inhibited meiotic maturation and spontaneous maturation, whereas AY9944 A-7 with any concentrations had no significant effect on that of denuded oocytes and split cumulus-oocyte complexes. Furthermore, maturing oocytes treated with either 10 or 20 µM AY9944 A-7 dramatically increased the percentages of ovine embryos developing to the two-cell stage and blastocyst stage. Higher concentrations of AY9944 A-7, 30 and 40 µM, were detrimental to oocytes and led to their degeneration. The present findings indicated for the first time that AY9944 A-7 was not only able to promote meiotic maturation, both Hx-inhibited and spontaneous, but also enhanced preimplantation developmental competence of prepubertal sheep oocytes maturing in vitro.


Asunto(s)
Anticolesterolemiantes/farmacología , Meiosis/efectos de los fármacos , Oocitos/efectos de los fármacos , Ovinos/fisiología , Diclorhidrato de trans-1,4-Bis(2-clorobenzaminometil)ciclohexano/farmacología , Animales , Anticolesterolemiantes/administración & dosificación , Técnicas de Cultivo de Célula , Transferencia de Embrión/veterinaria , Técnicas de Maduración In Vitro de los Oocitos/métodos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/citología , Oocitos/crecimiento & desarrollo , Maduración Sexual , Diclorhidrato de trans-1,4-Bis(2-clorobenzaminometil)ciclohexano/administración & dosificación
19.
Micron ; 50: 14-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23618746

RESUMEN

The objective of this study was to describe the ultrastructure of germ cells, Sertoli cells and mitochondria in mature testis of the Chinese Taihang black goat. The characteristics of germ cell nucleus and mitochondria changing during spermatogenesis were investigated by transmission electron microscopy (TEM). The results showed that the spermatogonium was elliptical, and its nucleus was about 4-5 µm. The round mitochondria can be observed throughout the cytoplasm around the nucleus. Small patches of heterochromatin were distributed throughout the nucleus. Spermatocyte was oval-shaped with a nucleus of about 4-4.5 µm in diameter. The heterochromatin began to attach to the inner surface of the nuclear membrane. Spermatid was about 4 µm and oval in shape. Its nucleus was oval or round and approximately 2-3 µm in diameter. The borderline between nucleus membrane and karyoplasm was distinct. During spermiogenesis, spermatid nucleus was condensed and elongated, and chromatin reached the highest condensation in the mature spermatozoon. The mid-piece was surrounded by mitochondria at the neck region. The sperm tail showed the typical "9+2″ structure, contained axoneme and central singlet microtubules. The nuclei of the Sertoli cells were irregular shaped and showed indentations in the membrane. In the mature testes of goat bucks, abundant mitochondria were around the germ cells and Sertoli cells. The scattered mitochondria were aggregated around the base of the flagellum (axoneme) during the spermatid differentiation stage. In conclusion, the present study showed that the spermatogenic process of Taihang black goat followed the pattern of mammals with some specific.


Asunto(s)
Células Germinativas/ultraestructura , Cabras/fisiología , Mitocondrias/ultraestructura , Células de Sertoli/ultraestructura , Espermatogénesis , Testículo/citología , Testículo/fisiología , Animales , Núcleo Celular/ultraestructura , China , Masculino , Microscopía Electrónica de Transmisión
20.
Anim Reprod Sci ; 135(1-4): 31-6, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23084568

RESUMEN

In this experiment the effect of maternal dietary selenium on the expression of Sel P and apoER2 of goat offspring was studied. The experiment was conducted on 119 Taihang Black Goats randomly divided into 4 groups which were fed with a basal diet, supplemented with 0 (control), 0.5, 2 and 4 mg kg(-1) DM Se. Testis samples were collected from young male of each treatment group at the end of the study (30 d after weaning) for mRNA expression using real-time PCR and for protein expression by immunohistochemistry assay. A significant decrease was observed in mRNA expression of Sel P and apoER2 in the testis of the Se-deficient (Group 1) and the Se-excess (Group 4) compared with that in Groups 2 and 3. A similar trend of the protein expression of Sel P and apoER2 was also found. These data indicate that maternal and dietary selenium has an effect on the expression of Sel P and apoER2 in testis of their offspring. In addition, both groups were similar suggesting that the relationship between Sel P and apoER2, and apoER2 is a receptor of Sel P in the seminiferous epithelium to uptake the selenium.


Asunto(s)
Cabras/metabolismo , Proteínas Relacionadas con Receptor de LDL/biosíntesis , Selenio/administración & dosificación , Selenoproteína P/biosíntesis , Testículo/efectos de los fármacos , Testículo/metabolismo , Animales , Suplementos Dietéticos , Femenino , Inmunohistoquímica/veterinaria , Proteínas Relacionadas con Receptor de LDL/genética , Proteínas Relacionadas con Receptor de LDL/metabolismo , Masculino , Exposición Materna/normas , Embarazo , ARN/química , ARN/genética , Distribución Aleatoria , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Selenio/metabolismo , Selenoproteína P/genética , Selenoproteína P/metabolismo
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