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1.
J Vet Sci ; 24(3): e39, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37271507

RESUMO

A 7-year-old spayed female Shih Tzu dog was presented for evaluation of recurrent hypoglycemia. Serum insulin levels during hypoglycemia were 35.3 µIU/mL. Ultrasonography and computed tomography showed a mesenteric nodule between the kidney and the portal vein, but no pancreatic mass was observed. During surgery, the nodule had neither anatomical adhesions nor vascular connections to the pancreas. Pancreatic inspection and palpation revealed no abnormalities. Hypoglycemia improved after resection of the nodule. Histopathological examination confirmed the nodule to be an islet cell carcinoma. Although extremely rare, ectopic insulinoma should be considered as a possible cause of insulin-induced hypoglycemia in dogs.


Assuntos
Carcinoma de Células das Ilhotas Pancreáticas , Doenças do Cão , Insulinoma , Animais , Cães , Insulinoma/veterinária , Doenças do Cão/cirurgia , Carcinoma de Células das Ilhotas Pancreáticas/veterinária , Feminino , Hipoglicemia/veterinária
2.
Microorganisms ; 9(4)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917817

RESUMO

Pectobacterium odoriferum has recently emerged as a widely infective and destructive pathogen causing soft-rot disease in various vegetables. Bacteriophage phiPccP-1 isolated from Pyeongchang, South Korea, showed lytic activity against P. odoriferum Pco14 and two other Pectobacterium species. The transmission electron microscopy and genome phylograms revealed that phiPccP-1 belongs to the Unyawovirus genus, Studiervirinae subfamily of the Autographivirinae family. Genome comparison showed that its 40,487 bp double-stranded DNA genome shares significant similarity with Pectobacterium phage DU_PP_II with the identity reaching 98% of the genome. The phiPccP-1 application significantly inhibited the development of soft-rot disease in the mature leaves of the harvested Kimchi cabbage up to 48 h after Pco14 inoculation compared to the untreated leaves, suggesting that phiPccP-1 can protect Kimchi cabbage from soft-rot disease after harvest. Remarkably, bioassays with phiPccP-1 in Kimchi cabbage seedlings grown in the growth chamber successfully demonstrated its prophylactic and therapeutic potential in the control of bacterial soft-rot disease in Kimchi cabbage. These results indicate that bacteriophage phiPccP-1 can be used as a potential biological agent for controlling soft rot disease in Kimchi cabbage.

3.
Am J Chin Med ; 44(6): 1099-1110, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27627913

RESUMO

Bearing pathologic and clinical similarities to human multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE) is used as a murine model to test potential therapeutic agents for MS. Recently, we reported the protective effects of an acidic polysaccharide of Panax ginseng (APG) in C57BL/6 strain-dependent EAE, a model of primary progressive MS. In this study, we extend our previous findings on the therapeutic capacity of APG in relapsing-remitting EAE (rr-EAE), the animal model to closely mimic recurrent inflammatory demyelination lesions of relapsing-remitting MS. Treatments with APG led to a significant reduction of clinical symptoms and the relapse rate of EAE than vehicle treatments. Consistent with this, histological examination revealed that APG markedly modulated the infiltration of CD4[Formula: see text] T cells and CD11b[Formula: see text] macrophages into the spinal cord and the APG-treated CNS was devoid of demyelination and axonal damages. In addition, APG decreased the proliferation of peripheral PLP-reactive T cells and the production of pro-inflammatory factors such as IFN-[Formula: see text], IL-17 and TNF-[Formula: see text]. The fact that APG can induce clinically beneficial effects to distinct types of EAE furthers our understanding on the basis of its immunosuppression in EAE and, possibly, in MS. Our results suggest that APG may serve as a new therapeutic agent for MS as well as other human autoimmune diseases, and warrants continued evaluation for its translation into therapeutic application.


Assuntos
Encefalomielite Autoimune Experimental/tratamento farmacológico , Panax/química , Fitoterapia , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Animais , Antígeno CD11b , Linfócitos T CD4-Positivos/imunologia , Células Cultivadas , Doenças Desmielinizantes , Modelos Animais de Doenças , Feminino , Humanos , Macrófagos/imunologia , Camundongos Endogâmicos C57BL , Esclerose Múltipla/tratamento farmacológico , Polissacarídeos/isolamento & purificação , Recidiva , Medula Espinal/imunologia , Medula Espinal/patologia
4.
Am J Vet Res ; 76(9): 814-21, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26309110

RESUMO

OBJECTIVE: To compare the characteristics and multipotential and in vivo cartilage formation capabilities of porcine adipose-derived stem cells (pASCs) with those of porcine skin-derived stem cell-like cells (pSSCs). ANIMALS: Three 6-month-old female pigs and four 6-week-old female athymic mice. PROCEDURES: Adipose and skin tissue specimens were obtained from each pig following slaughter and digested to obtain pASCs and pSSCs. For each cell type, flow cytometry and reverse transcription PCR assays were performed to characterize the expression of cell surface and mesenchymal stem cell markers, and in vitro cell cultures were performed to determine the adipogenic, osteogenic, and chondrogenic capabilities. Each cell type was then implanted into athymic mice to determine the extent of in vivo cartilage formation after 6 weeks. RESULTS: The cell surface and mesenchymal stem cell marker expression patterns, multipotential capability, and extent of in vivo cartilage formation did not differ significantly between pASCs and pSSCs. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that pSSCs may be a viable alternative to pASCs as a source of progenitor cells for tissue engineering in regenerative medicine.


Assuntos
Cartilagem/citologia , Diferenciação Celular/fisiologia , Condrogênese/fisiologia , Células-Tronco/fisiologia , Suínos , Tecido Adiposo/citologia , Animais , Células Cultivadas , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica/fisiologia , Células-Tronco Mesenquimais/citologia , Camundongos , Células-Tronco/citologia , Engenharia Tecidual
5.
Reprod Fertil Dev ; 27(7): 1088-96, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24718263

RESUMO

We tried to prevent the mitochondrial and DNA damage caused by mechanical stress-associated reactive oxygen species (ROS), and to improve the reprogramming of bovine somatic cell nuclear transfer (SCNT) embryos by antioxidant treatment during the manipulation procedures of SCNT. Bovine recipient oocytes and reconstituted oocytes were treated with antioxidants during manipulation procedures. The H2O2 level, mitochondrial morphology, membrane potential and apoptosis at the one-cell stage, and in vitro development and DNA methylation status of blastocysts were evaluated. Antioxidant treatment during manipulation procedures reduced the H2O2 level of SCNT embryos. Antioxidant-treated SCNT embryos normally formed mitochondrial clumps, similar to IVF embryos, and showed higher mitochondrial membrane potential versus the SCNT control (P<0.05). Apoptosis and DNA fragmentation were reduced by antioxidant treatment. The development rate to the blastocyst stage was higher (P<0.05) in the antioxidant treatment groups (30.5±2.5 to 30.6±1.6%) versus the control (23.0±1.9%). The DNA methylation status of blastocysts in the antioxidant treatment groups was lower (P<0.05) than that of the control and similar to that of IVF embryos. These results indicate that antioxidant treatment during manipulation procedures can prevent cellular damage that may be caused by mechanical stress-associated ROS, and improve nuclear reprogramming.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Blastocisto/efeitos dos fármacos , Reprogramação Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Mercaptoetanol/farmacologia , Mitocôndrias/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Blastocisto/metabolismo , Caspase 3/metabolismo , Bovinos , Fragmentação do DNA/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Feminino , Peróxido de Hidrogênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Técnicas de Transferência Nuclear , Espécies Reativas de Oxigênio/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-24382302

RESUMO

A novel phosphodiesterase-5 (PDE-5) inhibitor was found in a natural health food product. The previously unknown sildenafil analogue was isolated using preparative HPLC. The structure of the compound was elucidated using HPLC with diode array detection (DAD), time-of-flight mass spectrometry (TOF/MS), and nuclear magnetic resonance spectroscopy (NMR). An [M + H](+) ion was detected at m/z 505.2077 by LC-TOF/MS that was consistent with C23H32N6O3S2 (-0.98 ppm). By NMR analysis, the analogue was identified as 1-methyl-5-(5-(4-methylpiperazin-1-ylsulfonyl)-2-propoxyphenyl)-3-propyl-1H-pyrazolo[4,3-d]pyrimidine-7(6H)-thione. In this structure, the ethoxy group of thiosildenafil was substituted by a propoxy group of the unknown compound. Therefore, this novel thiosildenafil analogue was named propoxyphenyl thiosildenafil.


Assuntos
Contaminação de Alimentos/análise , Alimentos Orgânicos/análise , Inibidores da Fosfodiesterase 5/isolamento & purificação , Pirimidinas/isolamento & purificação , Sulfonas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Alimentos Orgânicos/efeitos adversos , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Estrutura Molecular , Inibidores da Fosfodiesterase 5/efeitos adversos , Inibidores da Fosfodiesterase 5/química , Pirimidinas/efeitos adversos , Pirimidinas/química , República da Coreia , Espectrometria de Massas por Ionização por Electrospray , Sulfonas/efeitos adversos , Sulfonas/química
7.
J Vet Sci ; 14(3): 235-40, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23820170

RESUMO

The generation of reactive oxygen species (ROS) and subsequent mitochondrial and DNA damage in bovine somatic cell nuclear transfer (SCNT) embryos were examined. Bovine enucleated oocytes were electrofused with donor cells and then activated by a combination of Ca-ionophore and 6-dimethylaminopurine culture. The H2O2 and ˙OH radical levels, mitochondrial morphology and membrane potential (ΔΨ), and DNA fragmentation of SCNT and in vitro fertilized (IVF) embryos at the zygote stage were analyzed. The H2O2 (35.6 ± 1.1 pixels/embryo) and ˙OH radical levels (44.6 ± 1.2 pixels/embryo) of SCNT embryos were significantly higher than those of IVF embryos (19.2 ± 1.5 and 23.8 ± 1.8 pixels/embryo, respectively, p < 0.05). The mitochondria morphology of SCNT embryos was diffused within the cytoplasm. The ΔΨ of SCNT embryos was significantly lower (p < 0.05) than that of IVF embryos (0.95 ± 0.04 vs. 1.21 ± 0.06, red/green). Moreover, the comet tail length of SCNT embryos was longer than that of IVF embryos (515.5 ± 26.4 µm vs. 425.6 ± 25.0 µm, p < 0.05). These results indicate that mitochondrial and DNA damage increased in bovine SCNT embryos, which may have been induced by increased ROS levels.


Assuntos
Apoptose , Dano ao DNA , DNA Mitocondrial/genética , Embrião de Mamíferos/citologia , Mitocôndrias/metabolismo , Técnicas de Transferência Nuclear/veterinária , Espécies Reativas de Oxigênio/metabolismo , Animais , Caspase 3/metabolismo , Bovinos , Colorimetria/veterinária , Ensaio Cometa/veterinária , DNA Mitocondrial/metabolismo , Transferência Embrionária/veterinária , Embrião de Mamíferos/embriologia , Fertilização in vitro/veterinária , Marcação In Situ das Extremidades Cortadas/veterinária , Potencial da Membrana Mitocondrial , Microscopia Confocal/veterinária , Microscopia de Fluorescência/veterinária
8.
Artigo em Inglês | MEDLINE | ID: mdl-23419124

RESUMO

A new tadalafil analogue, acetaminotadalafil, was detected by HPLC in a bulk powder that is being used as an ingredient formanufacturing dietary supplements. The analogue was isolated by semi-preparative HPLC. A chemical structure of the new compound was elucidated by HPLC, LC-quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS), nuclear magnetic resonance (NMR), infrared (IR) and circular dichroism (CD) spectroscopy. The compound was identified as an acetylatedcompound of aminotadalafil. The structure of the previous unknown compound was confirmed as (6R,12aR)-2-acetamino-6-(1,3-benzodioxol-5-yl)-2,3,6,7,12,12a-hexahydro-pyrazino[1',2':1,6]pyrido[3,4-b]indole-1,4-dione and named as acetaminotadalafil.


Assuntos
Carbolinas/análise , Suplementos Nutricionais/análise , Inibidores da Fosfodiesterase 5/análise , Carbolinas/química , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta , Tadalafila
9.
Biochem Biophys Res Commun ; 411(2): 464-70, 2011 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-21763286

RESUMO

Recently emerging evidence that the NF-κB family plays an important role in autoimmune disease has produced very broad and sometimes paradoxical conclusions. In the present study, we elucidated that the activation of RelA (p65) of NF-κB and IκB dissociation assumes a distinct role in experimental autoimmune encephalomyelitis (EAE) progression by altering IκB phosphorylation and/or degradation. In the present study of factors that govern EAE, the presence and immunoreactivity of nuclear RelA and phospho-IκB were recorded at the initiation and peak stage, and degradation of IκBα progressed rapidly at an early stage then stabilized during recovery. The immunoreactivity to RelA and phospho-IκB occurred mainly in inflammatory cells and microglial cells but only slightly in astrocytes. Subsequently, the blockade of IκB dissociation from NF-κB reduced the severity of disease by decreasing antigen-specific T cell response and production of IL-17 in EAE. Thus, blocking the dissociation of IκB from NF-κB can be utilized as a strategy to inhibit the NF-κB signal pathway thereby to reduce the initiation, progression, and severity of EAE.


Assuntos
Encéfalo/metabolismo , Encefalomielite Autoimune Experimental/metabolismo , Fosfoproteínas/metabolismo , Fator de Transcrição RelA/metabolismo , Animais , Encefalomielite Autoimune Experimental/patologia , Feminino , Quinase I-kappa B , Proteínas I-kappa B/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Tosilfenilalanil Clorometil Cetona
10.
Immunol Lett ; 138(2): 169-78, 2011 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-21524666

RESUMO

An acidic polysaccharide of Panax ginseng (APG), so called ginsan, is a purified polysaccharide. APG has multiple immunomodulatory effects of stimulating natural killer (NK) and T cells and producing a variety of cytokines that proved to diminish the proinflammatory response, and protect from septic lethality. To determine APG's role in the autoimmune demyelinating disease, we tested whether APG can regulate inflammatory and encephalitogenic response in experimental autoimmune encephalomyelitis (EAE), an animal model of human multiple sclerosis (MS). Here, we demonstrate the therapeutic efficacy of the APG which induces the suppression of an encephalitogenic response during EAE. APG significantly ameliorates the progression of EAE by inhibiting the proliferation of autoreactive T cells and the production of inflammatory cytokines such as IFN-γ, IL-1ß and IL-17. More importantly, APG promotes the generation of immunosuppressive regulatory T cells (Tregs) through the activation of transcription factor, Foxp3. Furthermore, the depletion of CD25+ cells from APG-treated EAE mice abrogates the beneficial effects of EAE. The capacity of APG to induce clinically beneficial effects furthers our understanding of the basis for its therapeutic immunosuppression of EAE and, possibly, MS. Thus, our results suggest that APG may serve as an effective therapy for MS and other autoimmune diseases.


Assuntos
Autoimunidade/efeitos dos fármacos , Encefalomielite Autoimune Experimental , Fatores de Transcrição Forkhead/metabolismo , Imunossupressores/farmacologia , Panax/química , Polissacarídeos/farmacologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Animais , Proliferação de Células/efeitos dos fármacos , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Fatores de Transcrição Forkhead/genética , Humanos , Imunossupressores/uso terapêutico , Interferon gama/biossíntese , Interleucina-10/biossíntese , Interleucina-17/biossíntese , Ativação Linfocitária/efeitos dos fármacos , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/genética , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Extratos Vegetais/química , Polissacarídeos/uso terapêutico , Linfócitos T Reguladores/efeitos dos fármacos , Células Th1/efeitos dos fármacos , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/imunologia , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/imunologia
11.
Acta Histochem ; 113(1): 19-23, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19767060

RESUMO

An acidic polysaccharide of Panax ginseng (APG), ginsan, has been reported to protect the hematopoietic system by increasing the number of bone marrow cells and spleen cells. Therefore, we evaluated the ability of APG to protect mice from radiation-induced damage of the small intestine. APG treatment caused the lengthening of villi and a numerical increase of crypt cells in the small intestine at 3.5 days after 7Gy irradiation compared to irradiated, non-treated controls. In addition, APG significantly inhibited irradiation-induced apoptosis by decreasing the amount of pro-apoptotic p53 and Bax as well as augmenting that of anti-apoptotic Bcl-2 at 24h after irradiation. These results indicate that APG might be a useful adjunct to therapeutic irradiation as a protective agent for the gastrointestinal tract of cancer patients.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Mucosa Intestinal/fisiopatologia , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/fisiopatologia , Intestino Delgado/efeitos da radiação , Panax , Polissacarídeos , Proteínas Proto-Oncogênicas/metabolismo , Protetores contra Radiação , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo , Animais , Western Blotting , Contagem de Células , Amarelo de Eosina-(YS) , Feminino , Raios gama , Hematoxilina , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Panax/química , Polissacarídeos/administração & dosagem , Proteínas Proto-Oncogênicas c-bcl-2 , Protetores contra Radiação/administração & dosagem , Protetores contra Radiação/química , Irradiação Corporal Total
12.
Mar Biotechnol (NY) ; 10(3): 278-89, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18172723

RESUMO

We investigated whether the brown seaweed Alariaceae Ecklonia cava (E. cava) has immunological effects on splenocytes in vitro. For that purpose, we prepared an enzymatic extract from E. cava (ECK) by using the protease, Kojizyme. Here, ECK administered to ICR mice dramatically enhanced the proliferation of their splenocytes and increased the number of their lymphocytes, monocytes and granulocytes. In flow cytometry assays performed to identify in detail the specific phenotypes of these proliferating cells after ECK treatment, the numbers of CD4(+) T cells, CD8(+) T cells and CD45R/B220(+) B cells increased significantly compared to those in untreated controls. In addition, the mRNA expression and production level of Th1-type cytokines, i.e., TNF-alpha and IFN-gamma, were down-regulated, whereas those of Th2-type cytokines, i.e., IL-4 and IL-10, were up-regulated by ECK. Overall, this dramatic increase in numbers of splenocytes indicated that ECK could induce these cells to proliferate and could regulate the production of Th1- as well as Th2-type cytokines in immune cells. These results suggest that ECK has the immunomodulatory ability to activate the anti-inflammatory response and/or suppress the proinflammatory response, thereby endorsing its usefulness as therapy for diseases of the immune system.


Assuntos
Enzimas/metabolismo , Fatores Imunológicos/imunologia , Phaeophyceae/química , Baço/citologia , Baço/imunologia , Animais , Linfócitos B/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Flavonoides/análise , Fluoresceínas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Contagem de Linfócitos , Camundongos , Camundongos Endogâmicos ICR , Phaeophyceae/metabolismo , Fenóis/análise , Fenótipo , Polifenóis , Polissacarídeos/análise , Polissacarídeos/química , Baço/efeitos dos fármacos , Succinimidas/metabolismo , Linfócitos T/efeitos dos fármacos
13.
Mol Reprod Dev ; 75(3): 464-71, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17948237

RESUMO

This study examined whether high osmolarity of culture medium at the early culture stage affects development and expression of apoptosis related genes (Bax-alpha and Bcl-xl) of porcine nuclear transfer (NT) and in vitro fertilization (IVF) embryos. NT and IVF embryos were divided into three groups and the basic medium was PZM-3 (260-270 mOsmol, control group). The control group of embryos was cultured in PZM-3 for whole culture period. Other two groups of embryos were cultured in a modified PZM-3 with 0.05 M sucrose (300-320 mOsmol, sucrose group) or increased NaCl to 138 mM (300-320 mOsmol, NaCl group) for the first 2 days, and then cultured in PZM-3 for 4 days. NT embryos cultured in NaCl group showed a significantly higher developmental rate to the blastocyst stage with a decreased apoptosis rate compared to the control (P < 0.05). There was no difference in blastocyst formation and apoptosis incidence among the three culture treatments for IVF-derived embryos. Bax-alpha mRNA expression was significantly higher in the control than sucrose or NaCl group for both NT and IVF embryos (P < 0.05). Moreover, the relative abundance of Bax-alpha/Bcl-xl was higher in the control than the treatment groups. These results indicate that the higher osmolarity at the early embryonic stage of porcine NT and IVF embryos can improve the in vitro development with reduced apoptosis through regulating the Bax-alpha/Bcl-xl gene expression.


Assuntos
Blastocisto/fisiologia , Meios de Cultura/farmacologia , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/efeitos dos fármacos , Suínos/embriologia , Proteína X Associada a bcl-2/genética , Proteína bcl-X/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Blastocisto/efeitos dos fármacos , Blastocisto/metabolismo , Células Cultivadas , Embrião de Mamíferos , Desenvolvimento Embrionário/genética , Fertilização in vitro , Regulação da Expressão Gênica no Desenvolvimento , Concentração Osmolar , Fatores de Tempo , Equilíbrio Hidroeletrolítico/fisiologia , Proteína X Associada a bcl-2/metabolismo , Proteína bcl-X/metabolismo
14.
J Reprod Dev ; 53(4): 843-51, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17460392

RESUMO

This study was conducted to determine the optimal vitrification conditions for immature bovine oocytes using the microdrop method. In experiment 1, the optimal pre-equilibration period for microdrop vitrification was examined. The maturation rate of vitrified oocytes with a 3 min first pre-equilibration period (41.1%) was higher than that of vitrified oocytes with a 0 min first pre-equilibration period (21.4%), and the values of those with a 1 (33.9%) or 5 min (27.4%) first pre-equilibration period were intermediate. The value for a 1 min second pre-equilibration period (44.4%) was significantly higher (P<0.05) than those for a 0.5 (28.6%) and 2 min (21.4%) second pre-equilibration period. In experiment 2, the distribution of microtubules in matured oocytes was investigated. There was no difference among the first pre-equilibration times in terms of the rates of normal spindles in vitrified oocytes. However, this value was significantly higher (P<0.05) in the 1 min group (52.8%) compared with the 0.5 (16.7%) and 2 min groups (12.3%). In experiment 3, we investigated the developmental capacity of immature bovine oocytes vitrified under optimal pre-equilibration conditions (3 min and 1 min for the first and second pre-equilibrations, respectively). Although the total fertilization rates were significantly lower (P<0.05) in the vitrified oocytes (65.6%) compared with the control oocytes (92.4%), there was no difference in the rate of normal fertilization (2PN) between the vitrified (78.6%) and control (82.0%) oocytes. Cleavage and blastocyst rates were significantly lower (P<0.05) in vitrified oocytes (55.7 and 2.3%) than in control oocytes (84.4 and 34.7%). Thus, these results indicated that immature bovine oocytes can survive after microdrop vitrification and subsequently can be cultured to mature oocytes capable of undergoing fertilization in vitro and developing into blastocysts.


Assuntos
Bovinos , Criopreservação/métodos , Fertilização in vitro/veterinária , Oócitos/citologia , Citoesqueleto de Actina/fisiologia , Animais , Apoptose , Blastômeros/citologia , Fase de Clivagem do Zigoto/citologia , Feminino , Fertilização , Microtúbulos/fisiologia , Oócitos/fisiologia , Bancos de Tecidos
15.
Mol Reprod Dev ; 73(9): 1094-101, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16736528

RESUMO

Artificial activation of oocytes is a pre-requisite for successful cloning by nuclear transfer (NT). This study investigated effect of different combination of activation chemicals such as electric pulse (E), thimerosal (Thi) + dithiothreitol (DTT), 6-dimethylaminopurine (6-DMAP), or cycloheximide (CH) on the developmental ability and the frequency of apoptosis of porcine NT embryos during the culture in vitro. NT embryos activated with chemicals showed significantly higher developmental rate to blastocyst stage compared to embryos activated with E alone (21.5%-26.6% vs. 15.7%, respectively). Of chemicals, Thi + DTT supported higher development to blastocyst stage as compared to 6-DMAP or CH (26.6% vs. 21.5%-23.4%, respectively). Apoptosis of NT embryos were analyzed by using a terminal deoxynucleatidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling (TUNEL) assay. The onset of apoptosis of embryos activated E alone was on Day 4, whereas embryos activated with chemicals showed apoptosis on Day 3 post-activation NT embryos exposed to chemicals for activation had higher frequency of apoptosis compared to that of embryos exposed to E alone from Day 3 to Day 7 during the culture. In conclusion, this study shows that chemical activation after fusion could increase not only the developmental ability of porcine NT embryos but also the mean cell number with an increased ratio of inner cell mass (ICM) to trophectoderm (TE) cells. However, the chemical activation also could increase the frequency of apoptosis and induced apoptosis earlier in porcine NT embryos.


Assuntos
Apoptose/efeitos dos fármacos , Blastocisto/citologia , Blastocisto/efeitos dos fármacos , Núcleo Celular/fisiologia , Técnicas de Transferência Nuclear , Suínos/embriologia , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Células Cultivadas , Cicloeximida/farmacologia , Ditiotreitol/farmacologia , Feminino , Técnicas In Vitro , Timerosal/farmacologia , Fatores de Tempo
16.
Mol Cell Biochem ; 270(1-2): 21-8, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15792350

RESUMO

The involvement of the p53 gene in apoptosis of many cell types towards y-radiation is well established. However, little information is available on the relationship between p53 status and cells' ability to undergo apoptosis following exposure to fast neutrons. The aim of this study was to characterize the apoptotic pathway traveled by neutrons in mouse intestinal crypt cells. Each mouse received whole body doses of 0.25-8 Gy fast neutrons and were sacrificed 0, 4, 6, 12, 24, 48, and 72 h, respectively, after irradiation. Apoptosis of crypt cells and expression of p53, cyclin A, cyclin B, cyclin D, and cyclin E were measured. The apoptosis in crypt cells was maximal at 4 and 6 h after irradiation, showing a gradual decline at 24 h. The highest frequency of apoptosis was seen at a 1 Gy dose and then declined gradually beyond a 2 Gy dose with high levels of damage. In immunoblot analysis, apoptosis was confirmed to be dependent on p53 function after fast-neutron irradiation. In addition, cyclin B1, cyclin D, and cyclin E were overexpressed in intestinal cells after fast-neutron irradiation and their immunoreactivities were increased strongly in round and oval cells of laminar propria in villi core and crypts. The results of the current study suggest that apoptosis in crypt cells shows a time- and dose-dependent increase after fast-neutron irradiation. In addition, fast-neutron-induced apoptosis in mouse intestinal crypt cells appears to be related to the increase in functional p53 proteins to a level sufficient to initiate apoptosis and up-regulation of cell-cycle-regulated proteins, which may lead to resistance to DNA damage through cell cycle arrest, is involved deeply in protection of gastrointestinal cells after low doses of fast-neutron irradiation.


Assuntos
Intestino Delgado/metabolismo , Intestino Delgado/efeitos da radiação , Proteína Supressora de Tumor p53/biossíntese , Animais , Apoptose , Ciclo Celular , Ciclinas/metabolismo , Relação Dose-Resposta à Radiação , Trato Gastrointestinal/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Immunoblotting , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Intestino Delgado/patologia , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Nêutrons , Fatores de Tempo , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima
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