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1.
Eur Rev Med Pharmacol Sci ; 27(7): 3191-3200, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37070922

RESUMO

A few patients who have recovered from COVID-19 develop persistent or new symptoms that last for weeks or months; this is called "long COVID" or "post-COVID-19 syndrome." Over time, awareness of the short- and long-term consequences of COVID-19 has increased. The pulmonary consequences are now fairly well established, but little is known about the extrapulmonary system of COVID-19, particularly its effects on bones. Current evidence and reports indicate a direct relationship between SARS-CoV-2 infection and bone health, with SARS-CoV-2 having a significant negative effect on bone health. In this review, we analyzed the impact of SARS-CoV-2 infection on bone health and assessed the impact of COVID-19 on the diagnosis and treatment of osteoporosis.


Assuntos
COVID-19 , Osteoporose , Humanos , Síndrome Pós-COVID-19 Aguda , SARS-CoV-2 , Densidade Óssea
2.
Phys Rev Lett ; 129(16): 163201, 2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36306764

RESUMO

Narrow optical resonances of atoms or molecules have immense significance in various precision measurements, such as testing fundamental physics and the generation of primary frequency standards. In these studies, accurate transition centers derived from fitting the measured spectra are demanded, which critically rely on the knowledge of spectral line profiles. Here, we propose a new mechanism of Fano-like resonance induced by distant discrete levels and experimentally verify it with Doppler-free spectroscopy of vibration-rotational transitions of CO_{2}. The observed spectrum has an asymmetric profile and its amplitude increases quadratically with the probe laser power. Our results facilitate a broad range of topics based on narrow transitions.

3.
Rev Sci Instrum ; 92(7): 073003, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34340416

RESUMO

Interactions between a molecule and two or more laser fields are of great interest in various studies, but weak and highly overlapping transitions hinder precision measurements. We present the method of comb-locked cavity-assisted double resonance spectroscopy based on narrow-linewidth continuous-wave lasers, which allows for state-selective pumping and probing of molecules. By locking two near-infrared diode lasers to one cavity with a finesse at the order of 105, we measured all three types of double resonances. Carbon monoxide molecules with selected speeds along the laser beam were excited to vibrationally excited states, and absorption spectra with sub-MHz linewidths were observed. Positions of double resonance transitions were determined with an accuracy of 3.7 kHz, which was verified by comparing to Lamb-dip measurements. The present work paves the way to the pump-probe study of highly excited molecules with unprecedented precision.

5.
Zhonghua Wai Ke Za Zhi ; 55(2): 141-145, 2017 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-28162215

RESUMO

Objective: To investigate the clinical values of multimodal preventive analgesia in patients with partial hepatectomy for liver cancer. Methods: A perspective study was conducted to collect data of patients with liver cancer who underwent partial hepatectomy from March 2014 to March 2015.The 90 patients involved in the study were randomly divided into two groups as multimodal analgesia and control groups, and each group had 45 cases. In multimodal analgesia group, 40 mg parecoxib sodium was injected intravenously 30 minutes before anesthetic induction, and 0.375% ropivacaine 150 mg combined with dexamethasone 5 mg were applied to transversus abdominis plane block before closing abdomen.The patients in control group without above treatment. Patient controlled intravenous analgesia was used in all patients. Three days after surgery, 40 mg parecoxib sodium was injected intravenously, twice a day for all patients.Visual analogue scales (VAS) was used to evaluate postoperative pain, and postoperative adverse events were observed.The number of cases of postoperative ambulation (>6 h for every day), time of flatus and defecation, and duration of hospital stay were recorded in two groups.Pearson chi-square test was used to compare the rate or constituent ratio between two groups.Independent sample t test or Mann-Whitney U was used to analyzed the measurement data between two groups. Results: There were no difference between two groups in aging, gender, weight, body mass index, ASA classification, blood loss volume, time of operation(all P>0.05). The scores of VAS in multimodal analgesia group was significantly lower than that in control group(3.0±0.8 vs. 4.6±1.1, t=7.814, P<0.01 for day 1; 2.2±1.0 vs. 3.6±1.2, t=5.825, P<0.01 for day 2; 1.6±0.8 vs. 2.4±1.2, t=3.894, P<0.01 for day 3). The number of cases of postoperative ambulation(>6 h) in multimodal analgesia group was significantly more than that in control group (10 cases vs. 0 case, χ(2)=11.250, P<0.01 for day 1; 21 cases vs. 5 cases, χ(2)=13.846, P<0.01 for day 2; 28 cases vs. 17 cases, χ(2)=5.378, P =0.020 for day 3). The time of flatus and defecation, and duration of hospital stay were significantly shorter than that in control group((30.2±7.3) hours vs. (36.4±7.0)hours, t=4.115, P<0.01 for flatus; (50.9±5.2)hours vs. (60.7±7.3)hours, t=7.346, P<0.01 for defecation; (6.2±0.8)days vs. (9.6±1.1)days, t=16.615, P<0.01 for hospital stay). Conclusion: Multimodal preventive analgesia effectively alleviate the postoperative pain, benefits early ambulation, improves recovery of gastrointestinal function, and shortens duration of hospital stay in patients with partial hepatectomy for liver cancer.


Assuntos
Analgesia/métodos , Hepatectomia , Neoplasias Hepáticas/cirurgia , Amidas , Humanos , Tempo de Internação , Manejo da Dor , Medição da Dor , Dor Pós-Operatória , Período Pós-Operatório , Ropivacaina
6.
Drug Discov Ther ; 7(6): 248-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24423656

RESUMO

We previous identified the antifibrotic active ingredients from Carapax Trionycis as two peptides. Here, we synthesized these two peptides (peptide 1 and peptide 2) by a solid phase method and examined their effects on proliferation and activation of cultured hepatic stellate cells (HSC) which are the main ECM (extracellular matrix)-producing cells in fibrosis progression. We demonstrated that peptide 1 and peptide 2 significantly reduced HSC proliferation and activation in a dose dependent manner. Further, peptide 1 and peptide 2 could interfere with TGF-signaling by down-regulating Smad 3 phosphorylation. Thus, these synthetic peptides of Carapax Trionycis could inhibit proliferation and activation of HSC and might be used as a candidate for treatment of liver fibrosis.


Assuntos
Exoesqueleto , Células Estreladas do Fígado/efeitos dos fármacos , Medicina Tradicional Chinesa , Proteínas de Répteis/farmacologia , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Tartarugas , Animais , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Matriz Extracelular/metabolismo , Humanos
7.
Br Poult Sci ; 52(1): 48-51, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21337197

RESUMO

1. Evidence has accumulated in mammals to support the idea that mitochondrial DNA (mtDNA) deletions and mutations might contribute to ageing and reproductive failure. White Roman geese were monitored to evaluate the effect of large-scale deletions of mtDNA in an avian species. 2. A total of 340 samples from 114 dead embryos, 111 weak goslings, and 115 normal goslings were used in this experiment. The regions of these two large-scale mtDNA deletions, ΔmtDNA6829 and ΔmtDNA6992, were between the COI and ND5 genes. A 3·6% (4 out of 111) positive sample was detected in the weak goslings. In contrast, no large-scale mitochondrial DNA deletions were detected in either the dead embryos (0 out of 114) or the normal goslings (0 out of 115). 3. Large-scale mtDNA deletions may be a factor causing weak goslings.


Assuntos
DNA Mitocondrial/química , Gansos/genética , Deleção de Sequência , Envelhecimento/genética , Animais , Sequência de Bases , Embrião não Mamífero/fisiologia , Gansos/embriologia , Gansos/fisiologia , Debilidade Muscular/genética , Reprodução/genética
8.
Braz. j. med. biol. res ; 44(2): 91-99, Feb. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-573653

RESUMO

Searching for effective Smad3 gene-based gene therapies for hepatic fibrosis, we constructed siRNA expression plasmids targeting the rat Smad3 gene and then delivered these plasmids into hepatic stellate cells (HSCs). The effect of siRNAs on the mRNA levels of Smad2, Smad3, Smad4, and collagens I-α1, III-α1 and IV-α1 (Colα1, Col3α1, Col4α1, respectively) was determined by RT-PCR. Eighty adult male Sprague-Dawley rats were randomly divided into three groups. Twice a week for 8 weeks, the untreated hepatic fibrosis model (N = 30) and the treated group (N = 20) were injected subcutaneously with 40 percent (v/v) carbon tetrachloride (CCl4)-olive oil (3 mL/kg), and the normal control group (N = 30) was injected with olive oil (3 mL/kg). In the 4th week, the treated rats were injected subcutaneously with liposome-encapsulated plasmids (150 µg/kg) into the right liver lobe under general anesthesia once every 2 weeks, and the untreated rats were injected with the same volume of buffer. At the end of the 6th and 8th weeks, liver tissue and sera were collected. Pathological changes were assessed by a semi-quantitative scoring system (SSS), and a radioimmunoassay was used to establish a serum liver fibrosis index (type III procollagen, type IV collagen, laminin, and hyaluronic acid). The mRNA expression levels of the above cited genes were reduced in the HSCs transfected with the siRNA expression plasmids. Moreover, in the treated group, fibrosis evaluated by the SSS was significantly reduced (P < 0.05) and the serum indices were greatly improved (P < 0.01). These results suggest that Smad3 siRNA expression plasmids have an anti-fibrotic effect.


Assuntos
Animais , Masculino , Ratos , Regulação para Baixo/genética , Células Estreladas do Fígado/metabolismo , Cirrose Hepática Experimental/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/uso terapêutico , /metabolismo , Tetracloreto de Carbono , Colágeno/metabolismo , Lipossomos , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/patologia , Plasmídeos , Radioimunoensaio , Distribuição Aleatória , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Interferência de RNA , RNA Mensageiro/metabolismo , Índice de Gravidade de Doença , /genética , Transfecção , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
9.
Braz J Med Biol Res ; 44(2): 91-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21103786

RESUMO

Searching for effective Smad3 gene-based gene therapies for hepatic fibrosis, we constructed siRNA expression plasmids targeting the rat Smad3 gene and then delivered these plasmids into hepatic stellate cells (HSCs). The effect of siRNAs on the mRNA levels of Smad2, Smad3, Smad4, and collagens I-α1, III-α1 and IV-α1 (Colα1, Col3α1, Col4α1, respectively) was determined by RT-PCR. Eighty adult male Sprague-Dawley rats were randomly divided into three groups. Twice a week for 8 weeks, the untreated hepatic fibrosis model (N = 30) and the treated group (N = 20) were injected subcutaneously with 40% (v/v) carbon tetrachloride (CCl4)-olive oil (3 mL/kg), and the normal control group (N = 30) was injected with olive oil (3 mL/kg). In the 4th week, the treated rats were injected subcutaneously with liposome-encapsulated plasmids (150 µg/kg) into the right liver lobe under general anesthesia once every 2 weeks, and the untreated rats were injected with the same volume of buffer. At the end of the 6th and 8th weeks, liver tissue and sera were collected. Pathological changes were assessed by a semi-quantitative scoring system (SSS), and a radioimmunoassay was used to establish a serum liver fibrosis index (type III procollagen, type IV collagen, laminin, and hyaluronic acid). The mRNA expression levels of the above cited genes were reduced in the HSCs transfected with the siRNA expression plasmids. Moreover, in the treated group, fibrosis evaluated by the SSS was significantly reduced (P < 0.05) and the serum indices were greatly improved (P < 0.01). These results suggest that Smad3 siRNA expression plasmids have an anti-fibrotic effect.


Assuntos
Regulação para Baixo/genética , Células Estreladas do Fígado/metabolismo , Cirrose Hepática Experimental/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/uso terapêutico , Proteína Smad3/metabolismo , Animais , Tetracloreto de Carbono , Colágeno/metabolismo , Lipossomos , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/patologia , Masculino , Plasmídeos , Interferência de RNA , RNA Mensageiro/metabolismo , Radioimunoensaio , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Índice de Gravidade de Doença , Proteína Smad3/genética , Transfecção , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
10.
Biochem Genet ; 48(11-12): 938-43, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20820906

RESUMO

In order to avoid interference from nuclear copies of mitochondrial DNA (numts), mtDNA of the white Roman goose (domestic goose) was extracted from liver mitochondria. The mtDNA control region was amplified using a long PCR strategy and then sequenced. Neighbor-joining, maximum parsimony, and maximum-likelihood approaches were implemented using the 1,177 bp mtDNA control region sequences to compute the phylogenetic relationships of the domestic goose with other geese. The resulting identity values for the white Roman geese were 99.1% (1,166/1,177) with western graylag geese and 98.8% (1,163/1,177) with eastern graylag geese. In molecular phylogenetic trees, the white Roman goose was grouped in the graylag lineage, indicating that the white Roman goose came from the graylag goose (Anser anser). Thus, the scientific name of the white Roman goose should be Anser anser 'White Roman.'


Assuntos
DNA Mitocondrial/genética , Gansos/genética , Filogenia , Animais , Sequência de Bases , China , DNA Mitocondrial/isolamento & purificação , Modelos Estatísticos , Dados de Sequência Molecular , Filogeografia , Análise de Sequência
11.
Heart ; 93(4): 488-90, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17065185

RESUMO

OBJECTIVE: To determine whether measurement of cardiac troponin T (cTnT) concentration in newly diagnosed peripartum cardiomyopathy (PPCM) can be used to predict persistent left ventricular dysfunction after a 6-month follow-up. PATIENTS AND METHODS: This was a prospective, multiple-centre clinical trial that studied 106 patients with newly diagnosed PPCM surviving over 6 months. cTnT concentration was measured within 2 weeks of the onset of PPCM. RESULTS: Serum cTnT concentration was negatively correlated with left ventricular ejection fraction (LVEF) at follow-up (LVEF, r = -0.518, p = 0.0001). Analysis by receiver operator characteristic curve yielded an area under the curve of 0.764 (95% CI 0.669 to 0.860, p = 0.0001, vs null hypothesis value 0.5) for cTnT, and a cTnT concentration cut off of >0.04 ng/ml, predicting persistent left ventricular dysfunction with a sensitivity of 54.9% and a specificity of 90.9%. Among 106 recruited patients, there were 33 patients with cTnT concentrations >0.04 ng/ml and 73 patients with cTnT concentrations < or =0.04 ng/ml. After a 6-month follow-up, there was significantly smaller LVEF (35.42% (13.04% vs 50.16% (10.48%, p = 0.0001) and more persistent left ventricular dysfunction (84.8% vs 31.5%, OR = 12.17 (95% CI 4.17 to 35.57), p = 0.001) in patients with cTnT >0.04 ng/ml than in patients with cTnT < or =0.04 ng/ml. CONCLUSION: Serum cTnT concentration measured within 2 weeks of the onset of PPCM was correlated negatively with LVEF at follow-up. This marker offers a simple, quick, inexpensive, non-invasive method for predicting a persistent LVEF of < or =50%. A cTnT concentration of >0.04 ng/ml predicted persistent left ventricular dysfunction with a sensitivity of 54.9% and a specificity of 90.9%.


Assuntos
Cardiomiopatias/sangue , Complicações Cardiovasculares na Gravidez/sangue , Transtornos Puerperais/sangue , Troponina T/metabolismo , Disfunção Ventricular Esquerda/diagnóstico , Adulto , Biomarcadores/sangue , Feminino , Humanos , Gravidez , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade
12.
Heart ; 92(8): 1096-101, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16387819

RESUMO

OBJECTIVE: To compare rate control and rhythm control strategies in patients with atrial fibrillation (AF) after percutaneous mitral balloon valvotomy (PMV). METHODS: 183 patients with AF after successful PMV, with AF duration

Assuntos
Fibrilação Atrial/terapia , Cateterismo/métodos , Adulto , Antiarrítmicos/uso terapêutico , Cardioversão Elétrica , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Qualidade de Vida , Tromboembolia/prevenção & controle , Resultado do Tratamento
13.
J Anim Sci ; 82 E-Suppl: E40-52, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15471814

RESUMO

Growth factors and steroids play an important role in the regulation of ovarian follicular development. In cattle, two of the earliest detectable differences between the healthy dominant follicle selected for development to the ovulatory stage and subordinate follicles destined to undergo atresia are the greater availability of IGF and the greater capacity to produce estradiol in the dominant follicle. We have shown that IGF-I and estradiol stimulate the proliferation of bovine granulosa cells in vitro and promote granulosa cell survival by increasing resistance to apoptosis. Furthermore, the ability of IGF-I and estradiol to increase resistance to apoptosis is tied to their ability to promote progression through the cell cycle. Blocking the cell cycle at the transition between the first gap phase and the DNA synthesis phase using a specific inhibitor prevented the protective effects of IGF-I and estradiol against apoptosis. Further experiments showed that the protective effect of IGF-I against apoptosis is mediated by the stimulation of phosphatidylinositol 3-kinase and its downstream target, protein kinase B/Akt. Constitutive activation of Akt by the infection of granulosa cells with a recombinant Akt adenovirus protected against apoptosis, and this effect also depended on cell cycle progression. These experiments show that the protective effect of estradiol and IGF-I against apoptosis depends on unperturbed progression through the cell cycle. Once follicles have developed to the preovulatory stage, the LH surge induces terminal differentiation of granulosa cells and withdrawal from the cell cycle. Bovine granulosa cells withdraw from the cell cycle by 12 h after the LH surge and become resistant to apoptosis, even in the absence of growth factors. Treatment with a progesterone receptor antagonist in vitro caused reentry of granulosa cells into the cell cycle and susceptibility to apoptosis, suggesting that induction of progesterone receptor expression by the LH surge is required for cell cycle withdrawal and resistance to apoptosis. In summary, the susceptibility of granulosa cells to apoptosis depends on the cell cycle. Proliferating granulosa cells in growing follicles depend on growth factors for survival, whereas cells that have terminally differentiated in response to the LH surge are resistant to apoptosis and relatively independent of growth factors for survival.


Assuntos
Animais Domésticos/fisiologia , Apoptose/fisiologia , Proliferação de Células , Atresia Folicular/fisiologia , Folículo Ovariano/fisiologia , Animais , Bovinos , Ciclo Celular/fisiologia , Sobrevivência Celular/fisiologia , Estradiol/fisiologia , Feminino , Hormônio Foliculoestimulante/fisiologia , Células da Granulosa/fisiologia , Fator de Crescimento Insulin-Like I/fisiologia , Camundongos , Ratos
14.
J Biomed Mater Res ; 57(4): 541-9, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11553884

RESUMO

The purpose of this study was to determine whether 0.8-1 mA, 2 Hz of percutaneous electrical stimulation could affect the regeneration of a 10-mm gap of rat sciatic nerve created between the proximal and distal nerve stumps, which were sutured into silicone rubber tubes. Six weeks after implantation, though the group receiving the electrical stimulation had a lower success percentage of regeneration (57%) compared with the controls receiving no stimulation (70%), quantitative histology of the successfully regenerated nerves revealed that the mean values of the axon density, blood vessel number, blood vessel area, and percentage of blood vessel area in total nerve area in the group with the electrical stimulation were all significantly larger than those in the controls (p < 0.05). These results showed that the electrical stimulation could elicit rehabilitating effects on the regenerated nerves.


Assuntos
Regeneração Nervosa/fisiologia , Nervo Isquiático/fisiologia , Elastômeros de Silicone , Estimulação Elétrica Nervosa Transcutânea , Animais , Materiais Biocompatíveis , Masculino , Músculo Esquelético/inervação , Ratos , Ratos Sprague-Dawley
15.
Yi Chuan Xue Bao ; 28(4): 327-44, 2001.
Artigo em Chinês | MEDLINE | ID: mdl-11329875

RESUMO

After the master cell stock(mcs) and working cell bank of more than 30 different strains of 7 animal kidney cell lines (F-81 or CRFK cell line, MDCK cell line, Vero or Vero-2 cell line, MA-104 cell line and BHK-21 cell line) were established in China, the chromosomal number variations and structural aberrations of the above lines, primary feline or canine kidney cell (FKC or CKC) and HeLa cell line were investigated and their karyotypes of routine or Giemsa chromosomal bands were analyzed. The carcinogenesis or tumorigenicity testing of these cells in about 700 nude mice and for colony formation in soft agar (SA) and for agglutination under different concentration of plant lectins was carried out. Both tumorigenicity-negative strains of F-81, CRFK, Vero or Vero-2 lines and very-low-tumorigenicity strains of MDCK line were successfully selected and evaluated for the production of canine or feline combination viral vaccines, which are free of infectious agents, and described with respect to cytogenetic characteristics and tumorigenicity. Rate of modal chromosome number represents the ratio of cell number having modal chromosome number to all the split cell number analyzed at random. Rate of difference represents the ratio of difference of the rate of modal chromosome number between mcs (master cell stock) + n and mcs passages. The chromosomal analysis results showed that the ratio of difference of the rate of modal chromosome number between mcs + n and mcs passages was not more than 5%-15% and the structure aberrations was generally 0%-3%, not more than 5%-10%, thus the hereditary character of cell lines is comparatively stable without significant difference between different passages. The genetic characteristics of chromosomal number of cell lines determines their tumorigenicity, but it is species specific. Experimental models were established for the researches on the prevention and prophylaxis of malignant tumors or cancers and their genetically biological characteristics. Tests showed that there was correlation among cell line chromosome number variations, anchorage independence in soft agar, agglutination under plant lectins and tumor-forming ability in nude mice. Since testing in vitro is more economic, simpler, faster, and is thought to be reliable, we recommend plant lectins followed by SA or analysis of karyotypes as the initial means for monitoring tumorigenicity of animal cell line in nude mice.


Assuntos
Aberrações Cromossômicas , Cariotipagem , Animais , Testes de Carcinogenicidade , Linhagem Celular , Chlorocebus aethiops , Bandeamento Cromossômico , Humanos , Camundongos , Camundongos Nus , Células Vero
16.
Biol Reprod ; 64(2): 518-26, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11159354

RESUMO

Ovarian follicular atresia occurs by apoptosis of granulosa and theca cells. The Fas antigen (Fas), a cell surface receptor that triggers apoptosis when activated by Fas ligand (FasL), may be involved in this process. A possible role of the Fas pathway in mediating serum withdrawal-induced apoptosis of granulosa cells was examined. Granulosa cells collected from 5- to 10-mm bovine follicles were cultured in DMEM-F12 containing serum for 3 days, deprived of serum, and live cells were counted at various times after serum withdrawal. Cell death increased significantly 6 h after serum withdrawal (21% +/- 7%; P: < 0.05 vs. 0 h) and continued to increase until 24 h (43% +/- 6%). No further increases in cell death were observed through 72 h. Detection of the translocation of phosphatidylserine to the outer surface of the cell membrane by annexin V binding indicated that cells died by apoptosis. Quantitative reverse transcriptase-polymerase chain reaction assays showed no changes in Fas mRNA levels but a 4.7-fold increase in FasL mRNA 3 h after serum withdrawal (P: < 0.05 vs. 0 h). FasL mRNA remained elevated through 24 h and returned to basal levels at 48 h. Immunohistochemical staining showed that both Fas and FasL protein increased on the cell surface within 3 h and remained elevated through 12 h (the last time point tested). Binding of FasL to Fas was blocked with two reagents that bind to the extracellular domain of FasL: an anti-FasL antibody and Fas:Fc, a chimeric protein consisting of the Fc portion of human immunoglobulin G and the extracellular domain of human Fas. Cell death 24 h after serum withdrawal was reduced 55% +/- 10% and 34% +/- 12% by anti-FasL antibody and Fas:Fc, respectively (P: < 0.05 vs. no blocking protein). In conclusion, serum withdrawal-induced apoptosis of bovine granulosa cells is mediated at least partially by Fas/FasL interactions. These results are consistent with a potential role of Fas in an autocrine or paracrine pathway to trigger ovarian follicular atresia.


Assuntos
Apoptose/fisiologia , Células da Granulosa/fisiologia , Glicoproteínas de Membrana/fisiologia , Receptor fas/fisiologia , Animais , Bovinos , Células Cultivadas , Clonagem Molecular , Meios de Cultura Livres de Soro , Proteína Ligante Fas , Feminino , Imuno-Histoquímica , Ligantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor fas/biossíntese
17.
Biomaterials ; 21(15): 1541-7, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10885726

RESUMO

A 10 mm gap of rat sciatic nerve was created between the proximal and distal nerve stumps, which were sutured into silicone rubber tubes filled with an extracellular gel containing collagen, laminin and fibronectin. Empty silicone rubber tubes were used as controls. Six weeks after implantation, all extracellular elements were completely degraded and absorbed, and 90% of the animals from the extracellular gel group exhibited regeneration across the nerve gaps, whereas only 60% in the control group. Both qualitative and quantitative histology of the regenerated nerves revealed a more mature ultrastructural organization with 28% larger cross-sectional area and 28% higher number of myelinated axons in the extracellular gel group than the controls. These results showed that the gel mixture of collagen, laminin and fibronectin could offer a suitable growth medium for the regeneration of axons.


Assuntos
Materiais Biocompatíveis , Colágeno , Fibronectinas , Laminina , Regeneração Nervosa/fisiologia , Nervo Isquiático/fisiologia , Silicones , Potenciais de Ação , Animais , Géis , Masculino , Músculo Esquelético/inervação , Músculo Esquelético/fisiologia , Fibras Nervosas/fisiologia , Fibras Nervosas/ultraestrutura , Próteses e Implantes , Ratos , Ratos Sprague-Dawley
18.
Trop Anim Health Prod ; 31(4): 245-57, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10504104

RESUMO

This study investigated the carcase composition of Taiwan simulated native chickens at different stages of growth. The results indicated that the carcases of male chickens exhibited significantly larger protein mass and water mass than those of females during weeks 7 to 20; as was the ash mass during weeks 8 to 20. However, the fat mass of the carcases of female chickens was larger than that of males during weeks 14 to 20. Separate regression equations were derived for the relationship between protein mass, fat mass, ash mass and water mass and both carcase weight and age of both male and female chickens.


Assuntos
Composição Corporal , Galinhas/crescimento & desenvolvimento , Carne/análise , Ração Animal , Animais , Ingestão de Energia , Gorduras/análise , Feminino , Masculino , Carne/normas , Proteínas/análise , Distribuição Aleatória , Análise de Regressão , Caracteres Sexuais , Taiwan , Água/análise
19.
Mol Reprod Dev ; 54(3): 209-14, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10497342

RESUMO

A sensitive technique for the sexing of bovine embryos was developed using polymerase chain reaction (PCR) amplification of the bovine amelogenin (bAML) gene on the X- and Y-chromosomes of Holstein dairy cattle. Cloning and DNA sequencing showed a 45.1% homology between the fifth intron of the bAML-X and bAML-Y gene with multiple deletions. A pair of sex-specific primers was designed to allow amplification of a single fragment of 467-bp from the X-chromosome of female cattle and two fragments of 467-bp and 341-bp from the X- and Y-chromosomes of male cattle. The primers were successfully applied to bovine sexing from single blastomeres isolated from day-6 to day-7 cow embryos by direct cell lysis and PCR. Our protocol of embryo sexing should be applicable to the diagnosis of defective genes in vitro in human embryos and in other domestic or recreational animals.


Assuntos
Blastômeros , Proteínas do Esmalte Dentário/genética , Reação em Cadeia da Polimerase/métodos , Processos de Determinação Sexual , Cromossomo X/genética , Cromossomo Y/genética , Amelogenina , Animais , Sequência de Bases , Southern Blotting , Bovinos , Clonagem Molecular , Feminino , Amplificação de Genes , Íntrons , Masculino , Modelos Genéticos , Dados de Sequência Molecular , Polimorfismo Genético/genética , Sensibilidade e Especificidade , Homologia de Sequência do Ácido Nucleico
20.
Zhonghua Shen Jing Jing Shen Ke Za Zhi ; 25(6): 355-7, 384-5, 1992 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-1305000

RESUMO

In the cerebral ischemic pathophysiologic mechanism, lactic acidosis is a important factor to exacerbate cerebral damage. Our research showed that the lactic level of cerebral cortex in rats increased rapidly after the focal cerebral ischemia or during blood reperfusion after cerebral ischemia, 26.99 +/- 5.89 and 28.63 +/- 5.08 mumol/g brain wight respectively, it exacerbated significantly brain edema and pathological damage. The lactic level decreased rapidly to treat with dichloroacetate (50 mg/kg body weight) after cerebral ischemia or during blood reperfusion, 14.11 +/- 2.06 and 13.23 +/- 1.71 mumol/g brain wight respectively, brain edema and pathology improved significantly. It suggested that dichloroacetate might across blood-brain barrier into the cerebral ischemic region and lowered lactic level, improved brain internal environment, relieved cerebral damage after focal cerebral ischemia or during blood reperfusion. It may improve the prognosis of patient with ischemic cerebral vascular disease to be treated with dichloroacetate early.


Assuntos
Acidose Láctica/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Ácido Dicloroacético/uso terapêutico , Acidose Láctica/etiologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/complicações , Lactatos/metabolismo , Ratos , Ratos Wistar , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/tratamento farmacológico
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