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1.
Clin Radiol ; 79(5): e767-e774, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38365539

RESUMEN

AIM: To evaluate the effect of aging on pulmonary vessels based on computed tomography (CT) quantification and analyse the correlation between quantitative pulmonary vascular volume and pulmonary function during aging. MATERIALS AND METHODS: A total of 330 healthy adult volunteers, including 161 men (53 aged 20-39 years, 61 aged 40-59 years, and 47 aged ≥60 years) and 169 women (53 aged 20-39 years, 63 aged 40-59 years, and 53 aged ≥60 years) were recruited in this study. AVIEW software was used to quantitatively measure pulmonary vascular volume, including pulmonary total blood vessel volume (TBV) and small blood vessel volume with a cross-sectional area of <5 mm2 (BV5). Pulmonary vascular volume parameters were standardised using the ratio of vascular volume to the body surface area (BSA; TBV/BSA and BV5/BSA). Subsequently, the effect of aging on the pulmonary vessels was analysed. RESULTS: The pulmonary vascular volume parameters TBV/BSA and BV5/BSA of the whole lung, right lung, and left lung decreased significantly with increasing age (p<0.05). Additionally, TBV/BSA and BV5/BSA of the whole lung were higher in men than in women. The declining trend of pulmonary vascular volume was consistent in men and women and increased with age. CONCLUSIONS: The pulmonary vascular volume parameters, TBV/BSA and BV5/BSA, decreased with age and were weakly positively correlated with pulmonary function.


Asunto(s)
Pulmón , Tomografía Computarizada por Rayos X , Masculino , Adulto , Humanos , Femenino , Tomografía Computarizada por Rayos X/métodos , Envejecimiento
2.
Andrologia ; 47(7): 765-78, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25251288

RESUMEN

The aim of this study was to isolate and characterise porcine spermatogonial stem cells (PSSCs). The putative porcine germline stem cells from testis were isolated successfully by an improving way of enrichment with lymphocyte separation medium (LSM). Results from RT-PCR analyses showed that PSSCs were positive for OCT4, SOX2, NANOG, PGP9.5, c-MYC, KEL4 and PRDM-14 which are multipotent stem cell markers. At the protein level, the results of immunofluorescence analyses showed that PSSCs were positive for OCT4, PGP9.5, SOX2 and CD29. We successfully differentiated these PSSCs into adipocytes and muscle cells and then defined their characteristics, including morphology, surface stem cell markers, and mechanical properties. But the experiment of teratoma formation was negative. The results indicated the PSSCs could be multipotent. Atomic force microscopy was used to characterise the morphological and mechanical properties of undifferentiated PSSCs, as well as the differentiated adipocytes and muscle cells, which could be potentially useful for distinguishing PSSCs from differentiated cells.


Asunto(s)
Animales Recién Nacidos , Espermatogonias/citología , Células Madre/citología , Testículo/citología , Adipocitos/citología , Animales , Diferenciación Celular , Células Cultivadas , Perfilación de la Expresión Génica , Masculino , Ratones , Ratones Desnudos , Microscopía de Fuerza Atómica , Datos de Secuencia Molecular , Músculos/citología , Células Madre/metabolismo , Porcinos , Teratoma/patología
4.
Abdom Imaging ; 39(6): 1323-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24831155

RESUMEN

PURPOSE: The purpose of this study was to investigate the imaging characteristics of solitary fibrous tumor (SFT) in the abdomen and pelvis. METHODS: Nine cases of SFT confirmed by surgery and pathology were retrospectively analyzed in terms of computed tomography (CT, eight cases) and magnetic resonance imaging (MRI, one case). RESULTS: SFT were located in the retroperitoneum (4/9), abdominal cavity (1/9), pelvis (4/9). Eight cases were single (8/9) and one case (1/9) with three tumors. The average tumor size of 11 lesions was 9.7 cm (4.7-20 cm). Nine tumors were round or ovoid, and two lesions were irregular. The CT value of the plain scans ranged from 33 to 43 Hounsfield units (HU, mean 37.6 HU) in five cases. Arterial-phase CT found solid parts demonstrate avid enhancement (eight cases) and five of them presented with multiple circuitous vessels along the periphery with a CT value of 68-89 HU (mean 76.6 HU). In the venous and delayed phases, enhancement was strengthened progressively. The CT values at venous (eight cases) and delayed phases (five cases) were 108-115 and 112-123 HU respectively, with averages of 109.8 and 114.8 HU. Patch or nodular no-enhanced areas were observed in eight cases during the enhanced phases. One case showed isointensity on T1-weighted images and high signal intensity on T2-weighted images accompanied by linear or curvilinear hypointense lines. Intense enhancements along with linear no-enhancement areas are seen in the arterial and venous phases. CONCLUSION: The possibility of SFT should be considered when a single or multiple masses with sharp border, inhomogeneous density or signal are detected, especially, with inhomogeneous intense enhancement in the arterial phase being maintained in the venous and delayed phases.


Asunto(s)
Neoplasias Abdominales/diagnóstico por imagen , Neoplasias Abdominales/patología , Neoplasias Pélvicas/diagnóstico por imagen , Neoplasias Pélvicas/patología , Tumores Fibrosos Solitarios/diagnóstico , Cavidad Abdominal/diagnóstico por imagen , Cavidad Abdominal/patología , Adulto , Anciano , Medios de Contraste , Femenino , Gadolinio DTPA , Humanos , Aumento de la Imagen/métodos , Yohexol/análogos & derivados , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Pelvis/diagnóstico por imagen , Pelvis/patología , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
5.
Zhonghua Liu Xing Bing Xue Za Zhi ; 45(2): 178-184, 2024 Feb 10.
Artículo en Zh | MEDLINE | ID: mdl-38413054

RESUMEN

Objective: To analyze the association between waist circumference (WC) and ischemic stroke (IS). Methods: The data for the present study were from the prospective cohort study of China Kadoorie Biobank in Qingdao. Using baseline information and IS events of the participants, the Cox proportional hazard regression model and restricted cubic spline (RCS) were used to analyze the association between WC and IS. Results: A total of 33 355 participants were included in the study, with 302 008.88 person-years of follow-up. A total of 1 093 new cases of IS were observed. Multivariate Cox proportional hazard regression model analysis showed that compared to the respondents with normal WC (male <85.0 cm, female <80.0 cm), respondents with excessive WC (male ≥85.0 cm, female ≥80.0 cm) had a 78% higher risk of IS incidence [hazard ratio(HR)=1.78, 95%CI: 1.51-2.10], and the risk increased by 72% (HR=1.72, 95%CI: 1.40-2.12) and 83% (HR=1.83, 95%CI: 1.40-2.39) in men and women. According to the RCS, the increase in WC and the risk of IS showed an "S" trend of nonlinear dose-response relationship. Conclusions: The risk of IS would increase with the WC. Keeping a normal WC is important for preventing IS.


Asunto(s)
Accidente Cerebrovascular Isquémico , Adulto , Humanos , Masculino , Femenino , Estudios Prospectivos , Circunferencia de la Cintura , Factores de Riesgo , Índice de Masa Corporal , China/epidemiología
6.
Nat Genet ; 26(3): 272-3, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11062462

RESUMEN

Success of cloning using adult somatic cells has been reported in sheep, mice and cattle. The report that 'Dolly' the sheep, the first clone from an adult mammal, inherited shortened telomeres from her cell donor and that her telomeres were further shortened by the brief culture of donor cells has raised serious scientific and public concerns about the 'genetic age' and potential developmental problems of cloned animals. This observation was challenged by a recent report that showed calves cloned from fetal cells have longer telomeres than their age-matched controls. The question remains whether Dolly's short telomeres were an exception or a general fact, which would differ from the telomeres of fetal-derived clones.


Asunto(s)
Bovinos/genética , Clonación de Organismos , Telómero/ultraestructura , Envejecimiento/genética , Animales , Senescencia Celular/genética , Femenino , Longevidad/genética , Ovinos/genética , Especificidad de la Especie
7.
Mol Biol (Mosk) ; 46(6): 900-6, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23350236

RESUMEN

The aim of this study was to examine the expression and regulation of angiopoietin-2 (Ang-2) in murine ovaries during sexual maturation, gonadotropin treatment and luteal development by in situ hybridization and RT-PCR. By in situ hybridization Ang-2 mRNA was mainly localized in granulosa cells, thecal cells and corpus luteum, otherwise in oocytes. Moreover, Ang-2 mRNA was highly expressed in corpus luteum and granulosa cells of atretic follicles. According to RT-PCR data, Ang-2 mRNA was lowly expressed on day 10 after birth, then expression levels gradually increased and reached their highest values on day 25 after birth. In the superovulated model of immature mice, Ang-2 expression was strongly induced by equine chorionic gonadotropin (eCG) 48 h post the eCG injection, and was high from 0.5 to 13 h after hCG treatment. In situ hybridization showed that Ang-2 mRNA was highly expressed in corpus luteum from day 2 to 9 post the hCG injection, then the expression levels gradually declined on days 11 and 13 after hCG treatment. According to RT-PCR data, the levels of Ang-2 mRNA expression showed a decline after the hCG injection, with a nadir on day 3, followed by an increase, reaching the highest level on day 9 post-hCG injection. Then again Ang-2 expression gradually declined from day 11 to 15 after hCG injection. These results suggest that Ang-2 may be involved in follicular development, atresia, ovulation, and corpus luteum formation and regression.


Asunto(s)
Angiopoyetina 2/biosíntesis , Cuerpo Lúteo/crecimiento & desarrollo , Regulación de la Expresión Génica/fisiología , Maduración Sexual/fisiología , Animales , Gonadotropina Coriónica/farmacología , Cuerpo Lúteo/citología , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Células de la Granulosa/citología , Células de la Granulosa/metabolismo , Caballos , Humanos , Ratones , ARN Mensajero/biosíntesis , Sustancias para el Control de la Reproducción/farmacología , Maduración Sexual/efectos de los fármacos , Factores de Tiempo
8.
Zhonghua Liu Xing Bing Xue Za Zhi ; 43(9): 1357-1363, 2022 Sep 10.
Artículo en Zh | MEDLINE | ID: mdl-36117339

RESUMEN

Objective: To analyze the association between body mass index (BMI) and coronary heart disease. Methods: The data for the present study were from the prospective cohort study of China Kadoorie Biobank (CKB) in Qingdao, a total of 33 355 participants aged 30-79 years were included in the study. Cox regression analyses were performed to evaluate the association between BMI and coronary heart disease. Results: During the follow-up for an average 9.2 years, a total of 2 712 cases of ischemic heart disease (IHD) and 420 cases of major coronary events (MCE) were found. Multivariate Cox regression analysis showed that, compared with participants with normal BMI, the participants who were overweight had a 41% and 87% higher risk of IHD and MCE, the adjusted HR were 1.41 (95%CI: 1.27-1.56) and 1.87 (95%CI: 1.43-2.44), respectively. The participants who were obesity had 91% and 143% higher risk of IHD and MCE, the adjusted HR were 1.91 (95%CI: 1.72-2.13) and 2.43 (95%CI: 1.82-3.24), respectively. Conclusion: Overweight and obesity might increase the risk for IHD and MCE.


Asunto(s)
Enfermedad Coronaria , Isquemia Miocárdica , Índice de Masa Corporal , Enfermedad Coronaria/epidemiología , Humanos , Isquemia Miocárdica/epidemiología , Obesidad/complicaciones , Obesidad/epidemiología , Sobrepeso/complicaciones , Sobrepeso/epidemiología , Estudios Prospectivos
9.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(8): 1280-1285, 2020 Aug 10.
Artículo en Zh | MEDLINE | ID: mdl-32867436

RESUMEN

Objective: To explore the associations between perceived built environment attributes and adults' leisure-time physical activity in four cities of China. Methods: Multistage cluster random sampling method was used to select adults aged 25 to 64 in Hangzhou, Suzhou, Chengdu, and Qingdao. Data were collected from June 2017 to July 2018. The perception of the urban built environment was assessed by the neighborhood environment walkability scale-abbreviated (NEWS-A), and the physical activity was assessed by the International Physical Activity Questionnaire. Generalized linear mixed models were used to explore the relationship between the perceived built environment and leisure-time physical activities. Results: A total of 3 789 participants were included in the analysis. After adjusting for potential confounders, better access to public services (OR=1.34, 95%CI: 1.02-1.75) and higher aesthetic quality (OR=1.37, 95%CI: 1.09-1.73) were positively associated with the possibility of engaging in leisure-time physical activity in the past week. Similarly, these two attributes were positively associated with leisure-time walking. Higher scores on the perception of street connectivity were positively associated with leisure-time walking [exp(ß)=1.09, 95%CI: 1.00-1.19]. Higher residential density [exp(ß)=1.000 4, 95%CI:1.000 0-1.000 8], better access to physical activity destinations[exp(ß)=1.09, 95%CI: 1.00-1.19], and better aesthetics [exp(ß)=1.11, 95%CI:1.00-1.22] were associated with higher leisure-time physical activity. Similarly, these three attributes were positively associated with the possibility of meeting the WHO recommendations. Conclusion: Changing some urban built environment attributes may increase leisure-time physical activity.


Asunto(s)
Entorno Construido/estadística & datos numéricos , Ejercicio Físico , Actividades Recreativas , Adulto , China , Ciudades , Humanos , Persona de Mediana Edad
10.
Sci Rep ; 9(1): 1217, 2019 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-30718778

RESUMEN

Transcript abundance of histone variants, modifiers of histone and DNA in bovine in vivo oocytes and embryos were measured as mean transcripts per million (TPM). Six of 14 annotated histone variants, 8 of 52 histone methyl-transferases, 5 of 29 histone de-methylases, 5 of 20 acetyl-transferases, 5 of 19 de-acetylases, 1 of 4 DNA methyl-transferases and 0 of 3 DNA de-methylases were abundant (TPM >50) in at least one stage studied. Overall, oocytes and embryos contained more varieties of mRNAs for histone modification than for DNA. Three expression patterns were identified for histone modifiers: (1) transcription before embryonic genome activation (EGA) and down-regulated thereafter such as PRMT1; (2) low in oocytes but transiently increased for EGA such as EZH2; (3) high in oocytes but decreased by EGA such as SETD3. These expression patterns were altered by in vitro culture. Additionally, the presence of mRNAs for the TET enzymes throughout pre-implantation development suggests persistent de-methylation. Together, although DNA methylation changes are well-recognized, the first and second orders of significance in epigenetic changes by in vivo embryos may be histone variant replacements and modifications of histones.


Asunto(s)
Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica , Histona Metiltransferasas/metabolismo , Histonas/genética , ARN Mensajero/metabolismo , Acetilación , Animales , Bovinos , Desmetilación , Embrión de Mamíferos/metabolismo , Epigénesis Genética , Histonas/metabolismo , Metilación , Oocitos/metabolismo
11.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(7): 759-764, 2019 Jul 10.
Artículo en Zh | MEDLINE | ID: mdl-31357794

RESUMEN

Objective: To evaluate the correlation between alcohol consumption and obesity in adults in China. Methods: The information about alcohol consumption were collected at the baseline survey of the China Kadoorie Biobank. The general obesity and central obesity were defined by BMI and waist circumference (WC) respectively. Logistic regression model was employed to examine the relationship of drinking behavior with general obesity and central obesity. Results: A total of 249 873 adults were included. A J-shaped relationship was observed between alcohol consumption and obesity measurement index (BMI and WC) in men. Compared with non-drinkers, the proportion of general obesity and central obesity were lower in light drinkers (men: OR=0.65, 95%CI: 0.59-0.71 and OR=0.93, 95%CI: 0.88-0.98; women: OR=0.77, 95%CI: 0.65-0.91 and OR=0.89, 95%CI: 0.80-0.99). In men, the proportion of general obesity and central obesity was highest in heavy drinkers (OR=1.21, 95%CI: 1.12-1.32; OR=1.33, 95%CI: 1.27-1.40). BMI and WC were higher in those with a drinking frequency of 3-5 d/week, with largest of proportion of central obesity (men: OR=1.23, 95%CI: 1.16-1.31; women: OR=1.13, 95%CI: 0.99-1.28). The risk for central obesity in men who began drinking every week before 20 years old was 1.24 times higher than non-drinkers (95%CI: 1.16-1.33). Those who drank beer had lower proportion of general obesity (men: OR=0.74, 95%CI: 0.67-0.82; women: OR=0.54, 95%CI: 0.43-0.68). Conclusion: The proportion of obesity was lower in light drinkers but higher in heavy drinkers; and the earlier drinking started, the higher the risk for obesity was.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Obesidad/epidemiología , Adulto , Consumo de Bebidas Alcohólicas/epidemiología , China/epidemiología , Femenino , Humanos , Masculino , Factores de Riesgo
12.
Zhonghua Liu Xing Bing Xue Za Zhi ; 40(5): 515-520, 2019 May 10.
Artículo en Zh | MEDLINE | ID: mdl-31177730

RESUMEN

Objective: To understand the fruit consumption of adults of Qingdao and examine the association between fruit consumption and stroke. Methods: We analyzed baseline data and stroke incidence of the participants who were aged 30-79 years and had been enrolled into the China Kadoorie Biobank (CKB) study from Qingdao city. Cox proportional hazards regression model was conducted to estimate the association of fruit consumption with risk of stroke. Results: A total of 35 509 participants were investgated in the baseline survey. Ratio of male to female was 1∶1.27, and the average age was (50.3±10.2) years. Respondents with higher frequency of fruit consumption were younger, more women, with higher education level and higher income (P<0.05). A total of 1 011 new cases of stroke were observed, with a stroke incidence of 387.63/100 000 person-years. Multivariate Cox regression analysis showed that fruit consumption had a protective effect on stroke incidence. Compared to the respondents who never consumed fruit, respondents who consumed fruit more than 4 days per week had a 44% lower risk of stroke incidence (HR=0.56, 95%CI: 0.50-0.62, P<0.05), and the risk reduced by 46% (HR=0.54, 95%CI: 0.46-0.64, P<0.05) and 42% (HR=0.58, 95%CI: 0.52-0.69, P<0.05) in male and female, respectively. Further adjustment for WC, BMI, SBP and random blood glucose did not change the association. Conclusion: Increasing fruit consumption can effectively decrease the risk of stroke. People should increase fruit consumption advisably to set up reasonable and healthy dietary habits.


Asunto(s)
Frutas , Accidente Cerebrovascular/epidemiología , Adulto , Anciano , China/epidemiología , Femenino , Humanos , Incidencia , Renta , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo
13.
Reprod Domest Anim ; 43 Suppl 2: 302-9, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18638139

RESUMEN

Somatic cell nuclear transfer (SCNT, 'cloning') holds great potential for agricultural applications, generation of medical model animals, transgenic farm animals or by 'therapeutic cloning' for generating human embryonic stem cells for the treatment of human diseases. However, the low survival rate of SCNT-derived pregnancies represents a serious limitation of the current technology. In order to overcome this hurdle, a deeper understanding of the epigenetic reprogramming of the somatic cell nuclei and its effect on the pregnancy is needed. Here we review the literature on nuclear reprogramming by SCNT, including studies of gene expression, DNA methylation, chromatin remodelling, genomic imprinting and X chromosome inactivation. Reprogramming of genes expressed in the inner cell mass, from which the body of the foetus is formed, seems to be highly efficient. Defects in the extra-embryonic tissues are probably the major cause of the low success rate of reproductive cloning. Methods to partially overcome such problems exist, yet more future research is needed to find practical and efficient methods to remedy this problem. Improvement of the survival of foetuses is a central issue for the future of agricultural SCNT not only for its economic viability, but also because in lack of improvements in animal welfare current regulations can block the use of the method in the EU and several other countries.


Asunto(s)
Animales Modificados Genéticamente , Clonación de Organismos , Epigénesis Genética/fisiología , Desarrollo Fetal/fisiología , Técnicas de Transferencia Nuclear , Bienestar del Animal , Animales , Reprogramación Celular , Clonación de Organismos/métodos , Metilación de ADN , Embrión de Mamíferos/fisiología , Desarrollo Fetal/genética , Regulación del Desarrollo de la Expresión Génica , Modelos Biológicos , Creación de Embriones para Investigación
14.
Mol Cell Biol ; 17(10): 6114-21, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9315671

RESUMEN

Ribonucleotide reductases catalyze the formation of deoxyribonucleotides by the reduction of the corresponding ribonucleotides. Eukaryotic ribonucleotide reductases are alpha2beta2 tetramers; each of the larger, alpha subunits possesses binding sites for substrate and allosteric effectors, and each of the smaller, beta subunits contains a binuclear iron complex. The iron complex interacts with a specific tyrosine residue to form a tyrosyl free radical which is essential for activity. Previous work has identified two genes in the yeast Saccharomyces cerevisiae, RNR1 and RNR3, that encode alpha subunits and one gene, RNR2, that encodes a beta subunit. Here we report the identification of a second gene from this yeast, RNR4, that encodes a protein with significant similarity to the beta-subunit proteins. The phenotype of rnr4 mutants is consistent with that expected for a defect in ribonucleotide reductase; rnr4 mutants are supersensitive to the ribonucleotide reductase inhibitor hydroxyurea and display an S-phase arrest at their restrictive temperature. rnr4 mutant extracts are deficient in ribonucleotide reductase activity, and this deficiency can be remedied by the addition of exogenous Rnr4p. As is the case for the other RNR genes, RNR4 is induced by agents that damage DNA. However, Rnr4p lacks a number of sequence elements thought to be essential for iron binding, and mutation of the critical tyrosine residue does not affect Rnr4p function. These results suggest that Rnr4p is catalytically inactive but, nonetheless, does play a role in the ribonucleotide reductase complex.


Asunto(s)
Genes Fúngicos/genética , Ribonucleósido Difosfato Reductasa/genética , Ribonucleótido Reductasas/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Secuencia de Aminoácidos , Clonación Molecular , Frío , Inhibidores Enzimáticos/farmacología , Dosificación de Gen , Regulación Fúngica de la Expresión Génica/fisiología , Genes Fúngicos/fisiología , Hidroxiurea/farmacología , Metilmetanosulfonato/farmacología , Datos de Secuencia Molecular , Mutágenos/farmacología , Mutación , Fenotipo , ARN de Hongos/biosíntesis , ARN Mensajero/biosíntesis , Ribonucleósido Difosfato Reductasa/antagonistas & inhibidores , Ribonucleótido Reductasas/antagonistas & inhibidores , Saccharomyces cerevisiae/enzimología , Proteínas de Saccharomyces cerevisiae/antagonistas & inhibidores , Homología de Secuencia de Aminoácido
15.
Theriogenology ; 68(8): 1128-37, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17875317

RESUMEN

This study was conducted to examine pregnancy progression and fetal characteristics following transfer of vitrified bovine nuclear transfer versus in vivo-derived embryos. Nuclear transfer (NT) was conducted using cumulus cells collected from an elite Holstein-Friesian dairy cow. Expanding and hatching blastocysts on Day 7 were vitrified using liquid nitrogen surface vitrification. Day 7 in vivo embryos, produced using standard superovulation procedures applied to Holstein-Friesian heifers (n=6), were vitrified in the same way. Following warming, embryos were transferred to synchronized recipients (NT: n=65 recipients; Vivo: n=20 recipients). Pregnancies were monitored by ultrasound scanning on Days 25, 45 and 75 and a sample of animals were slaughtered at each time point to recover the fetus/placenta for further analyses. Significantly more animals remained pregnant after transfer of in vivo-derived embryos than NT embryos at all time points: Day 25 (95.0 versus 67.7%, P<0.05), Day 45 (92.8 versus 49.1%, P<0.01) and Day 75 (70.0 versus 20.8%, P<0.0). There was no significant difference (P=0.10) in the weight of the conceptus on Day 25 from NT transfers (1.14+/-0.23 g, n=8) versus in vivo transfers (0.75+/-0.19 g, n=8). On Day 45, there was no significant difference in the weight of either fetus (P=0.393) or membranes (P=0.167) between NT embryos (fetus: 2.76+/-0.40, n=12; membranes: 59.0+/-10.0, n=11) or in vivo-derived embryos (fetus: 2.60+/-0.15, n=6; membranes: 41.8+/-5.2, n=4). However, on Day 75 the weight of the fetus and several of the major organs were heavier from NT embryos. These data suggest that morphological abnormalities involving the fetus and the placenta of cloned pregnancies are manifested after Day 45.


Asunto(s)
Bovinos/embriología , Clonación de Organismos/veterinaria , Feto/anatomía & histología , Técnicas de Transferencia Nuclear/veterinaria , Animales , Blastocisto/citología , Bovinos/fisiología , Transferencia de Embrión/veterinaria , Femenino , Peso Fetal , Técnicas de Transferencia Nuclear/normas , Tamaño de los Órganos , Embarazo , Índice de Embarazo , Factores de Tiempo
16.
J Dairy Sci ; 89(7): 2510-8, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16772569

RESUMEN

In vitro fertilization (IVF) is a feasible way to utilize sex-sorted sperm to produce offspring of a predetermined sex in the livestock industry. The objective of the present study was to examine the effects of various factors on bovine IVF and to systematically improve the efficiency of IVF production using sex-sorted sperm. Both bulls and sorting contributed to the variability among differential development rates of embryos fertilized by sexed sperm. Increased sorting pressures (275.8 to 344.75 kPa) did not have a significant effect on the in vitro fertility of the sorted sperm; neither did an extended period of 9 to 14 h from semen collection to sorting. As few as 600 sorted sperm were used to fertilize an oocyte, resulting in blastocyst development of 33.2%. Postwarming of vitrified sexed IVF embryos resulted in high morphological survival (96.3%) and hatching (84.4%) rates, similar to those fertilized by nonsexed sperm (93.1 and 80.6%, respectively). A 40.9% pregnancy rate was established following the transfer of 3,627 vitrified, sexed embryos into synchronized recipients. This was not different from the rates with nonsexed IVF (41.9%, n = 481), or in vivo-produced (53.1%, n = 192) embryos. Of 458 calves born, 442 (96.5%) were female and 99.6% appeared normal. These technologies (sperm sexing-IVF-vitrification-embryo transfer) provide farmers, as well as the livestock industry, with a valuable option for herd expansion and heifer replacement programs. In summary, calves were produced using embryos fertilized by sex-sorted sperm in vitro and cryopreserved by rapid cooling vitrification.


Asunto(s)
Bovinos/embriología , Criopreservación/veterinaria , Desarrollo Embrionario/fisiología , Fertilización In Vitro/veterinaria , Preselección del Sexo/veterinaria , Espermatozoides , Animales , Separación Celular/veterinaria , Técnicas de Cultivo de Embriones/veterinaria , Transferencia de Embrión/veterinaria , Femenino , Citometría de Flujo/veterinaria , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Embarazo , Análisis para Determinación del Sexo/veterinaria , Espermatozoides/citología
17.
Theriogenology ; 65(9): 1704-15, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16256185

RESUMEN

The swamp buffalo (Bubalus bubalis) is a multi-purpose animal in agriculture that is challenged by extinction due to low reproductive efficiency. Nuclear transfer (NT) has been used to preserve special breeds of buffalo, as well as to increase the number of animals. However, cloned buffalo embryos have impaired development, as in other species. To understand the chromatin remodeling activities in cloned embryos and to improve NT technology, we examined the expression profiles of five genes involved in DNA and histone modifications, DNMT1, DNMT3A, DNMT3B, HAT1 and HDAC1, in single swamp buffalo metaphase II oocytes, NT and in vitro fertilized (IVF) embryos from the two-cell to the blastocyst stage, by quantitative real time RT-PCR. We observed similar expression dynamics for all genes studied in the NT and IVF embryos: relatively constant levels of expression for all genes were found from the MII oocyte up to the eight-cell stage; the levels of mRNA for HAT1 and DNMT3B continued to be stably expressed up to the blastocyst stage; while dramatic increases were seen for DNMT3A and HDAC1. Alternatively, the levels of DNMT1 started to decrease at the eight-cell stage. Despite the similarity in the dynamics of gene expression, dramatic differences in the relative levels of these genes between NT and IVF embryos were observed. The expression levels of all DNA modifying genes were higher in the NT embryos than in the IVF embryos at the eight-cell and blastocyst stages. The genes HDAC1 and HAT1 were also expressed significantly higher at the blastocyst stage in the NT embryos. Our results suggested differences in chromatin remodeling between NT and IVF embryos and that lower levels of DNA passive demethylation and higher levels of DNA de novo methylation occurred in the NT embryos. These observations are novel in the species of buffalo, and may be associated with developmental failure of cloned buffalo embryos due to the transcriptional repression effect of most genes studied here.


Asunto(s)
Búfalos/genética , Ensamble y Desensamble de Cromatina/genética , Clonación de Organismos , ARN Mensajero/análisis , Acetiltransferasas/genética , Animales , Búfalos/embriología , Metilación de ADN , Desarrollo Embrionario , Fertilización In Vitro/veterinaria , Histona Acetiltransferasas , Histona Desacetilasas/genética , Histonas/genética , Técnicas de Transferencia Nuclear , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
18.
Theriogenology ; 66(8): 1951-60, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16787658

RESUMEN

This study was conducted to compare the efficacy of four in vitro fertilization (IVF) media: Bracket and Oliphant's medium (BO), modified medium 199 (IVF-M199), modified Tyrode's medium (MTM), and modified KSOM (m-KSOM) on fertilization efficiency and blastocyst formation rate. In addition, we wanted to investigate the benefit of prolonging the IVF period (from 6 to 18 h) using the two most effective IVF media determined in our initial experiment; subsequently, blastocyst viability was assessed following vitrification. A higher incidence of polyspermic fertilization was observed in the MTM (6%) and in BO, in both the 6 and 18 h (7% and 11%, respectively) groups, than in the m-KSOM (1%) or in the IVF-M199 6 or 18 h (1 and 3%, respectively) groups. Cleavage rates were similar in BO, IVF-M199, and MTM 48 h post-fertilization; however, the lowest cleavage rate was observed for m-KSOM. A greater proportion of zygotes developed into 8-cell embryos in IVF-M199 than in other IVF media. Subsequently, a greater proportion of blastocyst formation and hatching was achieved in IVF-M199 (40% and 79%, respectively) or BO (35% and 74%, respectively) than in m-KSOM (18% and 58%, respectively) or MTM (22% and 66%, respectively). Prolonging IVF to 18 h did not alter cleavage rates; however, the highest rate of overall blastocyst formation was achieved in the IVF-M199 18 h (49%), rather than in the BO 18 h (20%) group. Vitrified/thawed blastocysts from IVF-M199 groups re-expanded and developed better, as compared to the BO 18 h group, and hatching rate and total cell number in IVF-M199 18 h group was comparable to the control groups (non-vitrified). Vitrification reduced survival compared to controls. In conclusion, IVF-M199 was successfully used for IVF, compared favorably to BO medium, and offered the advantage of an extended IVF period for up to 18 h that requires only one-half a dose of semen, and resulted in better quality blastocysts that endured vitrification with a hatching rate comparable to that of control groups.


Asunto(s)
Blastocisto , Criopreservación/veterinaria , Medios de Cultivo/farmacología , Técnicas de Cultivo de Embriones/veterinaria , Desarrollo Embrionario/fisiología , Fertilización In Vitro/veterinaria , Animales , Blastocisto/efectos de los fármacos , Blastocisto/fisiología , Bovinos , Criopreservación/métodos , Medios de Cultivo/química , Técnicas de Cultivo de Embriones/métodos , Transferencia de Embrión/veterinaria , Femenino , Fertilización In Vitro/métodos , Fertilización In Vitro/normas , Masculino , Factores de Tiempo , Supervivencia Tisular
19.
Eur Rev Med Pharmacol Sci ; 20(11): 2302-9, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27338055

RESUMEN

OBJECTIVE: Hepatocellular carcinoma (HCC) is a common cause of tumor-related deaths worldwide. Previous studies have shown that increased systemic inflammation and platelet-to-lymphocyte ratio (PLR) are associated with poor prognosis of various cancers. The objective of the present study was to investigate the effects of pretreatment PLR on survival in patients with hepatitis B virus (HBV)-related HCC who underwent repeated transarterial chemoembolization (TACE). PATIENTS AND METHODS: A total of 122 patients with HBV-related HCC who underwent TACE from two centers in the central China were analyzed retrospectively and were separated into two groups based on the median value of neutrophil-to-lymphocyte ratio (NLR; low: < 2.61 or high: ≥ 2.61) and PLR (low: < 96.13 or high: ≥ 96.13). RESULTS: Patients with low pretreatment PLR and NLR had a higher rate of overall survival compared with patients with a high PLR and NLR (log-rank test). Univariate analyses indicated that a high PLR was a significant risk factor for poor survival (p = 0.022), and multivariate analyses further showed that a high PLR was an independent factor that predicted worse survival (p = 0.001). CONCLUSIONS: We suggest that a high pretreatment PLR is a useful prognosticator for poor survival in patients with HBV-related HCC undergoing TACE.


Asunto(s)
Carcinoma Hepatocelular , Virus de la Hepatitis B , Neoplasias Hepáticas , Plaquetas , Quimioembolización Terapéutica , Humanos , Linfocitos , Pronóstico , Factores de Riesgo
20.
Trends Cardiovasc Med ; 11(8): 313-7, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11728879

RESUMEN

Cloning by nuclear transfer has great potential application in pharmaceutical protein production, xeno-transplantation, and perhaps most excitingly, therapeutic cloning. In therapeutic cloning a patient's own skin cells can be used to generate cloned embryos from which embryonic stem cells are isolated. Through targeted differentiation, embryonic stem cells can be directed to develop into the desired tissues/organs for replacement. The combination of homologous recombination of genes and nuclear transfer also offers the promise of correcting defective genes in humans. Demonstration of the successful cloning of aged animals is important for these future medical applications because degenerative diseases often afflict older adults. Our studies have demonstrated that skin fibroblast cells from aged adults, even after prolonged culture, provide nuclear donors equally as competent for cloning as cells from young adults or fetuses. These findings have paved the way for medically treating degenerative diseases of aged humans by tissue regeneration technologies made possible through cloning and homologous recombination.


Asunto(s)
Clonación de Organismos/métodos , Técnicas de Transferencia Nuclear , Factores de Edad , Animales , Diferenciación Celular , Clonación de Organismos/tendencias , Humanos , Modelos Animales
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