Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
J Dairy Sci ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642647

RESUMO

Massive genotyping in cattle has uncovered several deleterious haplotypes that cause pre-term mortality. Holstein Haplotype 5 (HH5) is a deleterious haplotype present in the Holstein Friesian population that involves the ablation of the Transcription Factor B1 mitochondrial (TFB1M) gene. The developmental stage at which HH5 double-carrier (DC, homozygous) embryos or fetuses die remains unknown and this is a relevant information to estimate the economic losses associated to the inadvertent cross between carriers. To determine if HH5 DC survive to maternal recognition of pregnancy, embryonic day (E)14 embryos were flushed from superovulated carrier cows inseminated with a carrier bull. DC E14 conceptuses were recovered at Mendelian rates but they failed to achieve early elongation, as evidenced by a drastic (>26-fold) reduction in the proliferation of extraembryonic membranes compared with carrier or non-carrier embryos. To assess development at earlier stages, TFB1M knockout (KO) embryos -functionally equivalent to DC embryos- were generated by CRISPR technology and cultured to the blastocyst stage -Day (D)8- and to the early embryonic disc stage -D12-. No significant effect of TFB1M ablation was observed on the differentiation and proliferation of embryonic lineages and relative mtDNA content up to D12. In conclusion, HH5 DC embryos are able to develop to early embryonic disc stage but fail to undergo early conceptus elongation, required for pregnancy recognition.

2.
Reprod Fertil Dev ; 35(12): 614-621, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37430407

RESUMO

CONTEXT: Arachidonic acid (AA) is the precursor of prostaglandins, which may play autocrine roles during early embryo development. AIMS: To test the developmental effects of addition of AA to pre- and post-hatching culture media on in vitro -produced bovine embryos. METHODS: Pre-hatching effects of AA were tested by culturing bovine zygotes in synthetic oviductal fluid (SOF) supplemented with 100 or 333µM AA. Post-hatching effects of AA were tested by culturing Day 7 blastocysts in N2B27 supplemented with 5, 10, 20 or 100µM AA up to Day 12. KEY RESULTS: Pre-hatching development to blastocyst was completely abrogated at 333µM AA, whereas blastocyst rates and cell numbers were not altered at 100µM AA. Impaired post-hatching development was observed at 100µM AA, whereas no effect on survival rates was noted at 5, 10 and 20µM AA. However, a significant reduction in Day 12 embryo size was observed at 10 and 20µM AA. Hypoblast migration, epiblast survival and formation of embryonic-disc-like structures were unaffected at 5-10µM AA. AA exposure downregulated the genes PTGIS , PPARG , LDHA and SCD in Day 12 embryos. CONCLUSIONS: Pre-hatching embryos are mostly irresponsive to AA, whereas AA was observed to have negative effects during early post-hatching development. IMPLICATIONS: AA does not improve in vitro bovine embryo development and is not required up to early post-hatching stages.


Assuntos
Blastocisto , Fertilização in vitro , Animais , Bovinos , Ácido Araquidônico/farmacologia , Fertilização in vitro/veterinária , Embrião de Mamíferos , Desenvolvimento Embrionário , Técnicas de Cultura Embrionária/veterinária
3.
Theriogenology ; 205: 73-78, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37087966

RESUMO

Ungulate embryos undergo critical cell differentiation and proliferation events around and after blastocyst hatching. Failures in these processes lead to early pregnancy losses, which generate an important economic impact on farming. Conventional embryo culture media, such as SOF, are unable to support embryo development beyond hatching. In contrast, N2B27 medium supports early post-hatching development, evidencing a swift in embryonic nutritional requirements during this developmental window. Here, we investigate if earlier exposure to N2B27 could improve embryo development after hatching. Embryo culture in N2B27 from day (D) 5, 6 or 7 significantly enhanced complete hypoblast migration (>45 vs. ∼24%) and epiblast development into an embryonic disc (ED)-like structure at D12 (>40 vs. 23%), compared to embryos cultured in SOF up to D9. Culture in N2B27 from D5 significantly increased epiblast and hypoblast cell number in D8 blastocysts, but post-hatching embryos cultured in N2B27 from D5 or 6 frequently showed a disorganized distribution of epiblast cells. In conclusion, bovine embryo culture in N2B27 from D7 onwards improves subsequent post-hatching development. This improved fully in vitro system will be very useful to functionally explore cell differentiation mechanisms and the bases of early pregnancy failures without requiring animal experimentation.


Assuntos
Aborto Animal , Doenças dos Bovinos , Gravidez , Feminino , Bovinos , Animais , Blastocisto/fisiologia , Embrião de Mamíferos , Parto , Diferenciação Celular , Desenvolvimento Embrionário/fisiologia , Técnicas de Cultura Embrionária/veterinária , Fertilização in vitro/veterinária
6.
Neuroscience ; 208: 97-108, 2012 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-22366222

RESUMO

New neurons are continuously generated in the hippocampus and may play an important role in many physiological and pathological conditions. Here we present evidence of cell proliferation and neurogenesis after a selective and transient excitotoxic injury to the hippocampal cornu ammonis 1 (CA1) area induced by low concentrations of domoic acid (DOM) in rat organotypic hippocampal slice cultures (OHSC). DOM is an excitatory amino acid analog to kainic acid that acts through glutamate receptors to elicit a rapid and potent excitotoxic response. Exposure of slice cultures to varying concentrations of DOM for 24 h induced dose-dependent neuronal toxicity that was independent of activation of classic apoptotic markers. Treatment with 2 µM DOM for 24 h caused a selective yet transient neurotoxic injury in the CA1 subfield of the hippocampus that appeared recovered after 7 days of incubation in a DOM-free medium and showed significant microgliosis but no sign of astrogliosis. The DOM insult (2 µM, 24 h) resulted in a significant upregulation of cell proliferation, as assessed by 5-bromo-2-deoxyuridine (BrdU) incorporation, and a concurrent increase of the neuronal precursor cell marker doublecortin (DCX) within the subgranular zone of the dentate gyrus and area CA1. Neurogenesis occurred primarily during the first week after termination of the DOM exposure. Our study shows that exposure of OHSC to concentrations of DOM below those required to induce permanent neurotoxicity can induce proliferation and differentiation of neural progenitor cells that may contribute to recovery from mild injury and to develop abnormal circuits relevant to disease.


Assuntos
Hipocampo/citologia , Hipocampo/crescimento & desenvolvimento , Hipocampo/metabolismo , Ácido Caínico/análogos & derivados , Neurogênese/efeitos dos fármacos , Fármacos Neuromusculares Despolarizantes/toxicidade , Animais , Antimetabólitos , Apoptose/efeitos dos fármacos , Benzimidazóis , Bromodesoxiuridina , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/crescimento & desenvolvimento , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Corantes , Relação Dose-Resposta a Droga , Proteína Duplacortina , Imunofluorescência , Corantes Fluorescentes , Hipocampo/efeitos dos fármacos , Imuno-Histoquímica , Ácido Caínico/toxicidade , Microglia/enzimologia , Microglia/metabolismo , Técnicas de Cultura de Órgãos , Propídio , Ratos , Ratos Sprague-Dawley
7.
Theriogenology ; 71(6): 1005-10, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19157529

RESUMO

Neurotrophins and basic fibroblast growth factor are ligands of tyrosine kinase receptors, though they bind to different tyrosine kinase receptor classes. Neurotrophins bind to receptor tyrosine kinase class VII, Trk receptor family, while basic fibroblast growth factor binds to receptor tyrosine kinase class IV, FGF receptor family. The mammalian uterine tract immunolocalizes neurotrophins and bFGF; therefore their cognate receptors might exert a role during embryonic development. Using RT-PCR, we found mRNA for p75(NTR) TrkA, TrkC and FGFr2 throughout the early bovine embryonic development in vitro. Immunofluorescent staining, assessed by confocal microscopy, showed the expression of TrkA and TrkC proteins in oocytes and all embryonic stages analyzed. We have provided a novel description of TrkA and TrkC proteins, and TrkA, TrkC, p75(NTR) and FGFr2 mRNA expression throughout mammalian embryonic development. This work may help to design future research with neurotrophins in bovine embryo culture and embryonic stem cells.


Assuntos
Bovinos/embriologia , Técnicas de Cultura Embrionária/veterinária , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/análise , Receptor trkA/análise , Receptor trkC/análise , Animais , Blastocisto/química , Western Blotting , Desenvolvimento Embrionário , Imunofluorescência , Imuno-Histoquímica , Microscopia Confocal , Mórula/química , Oócitos/química , RNA Mensageiro/análise , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor trkA/genética , Receptor trkC/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Zigoto/química
8.
Adicciones (Palma de Mallorca) ; 19(4): 409-421, oct.-dic. 2007.
Artigo em Es | IBECS | ID: ibc-62750

RESUMO

La presente investigación examina el concepto de recuperación natural de los problemas derivados del consumo de alcohol, marihuana, cocaína y heroína, cada una sola o en cualquier combinación. Se trabajó con dos grupos de sexo masculino y dos de sexo femenino (40 hombres entre 18 y 60 años, y 19 mujeres entre 18 y 55 años) de la ciudad de Bogotá que tenían por lo menos un año de abstinencia. Se analizaron principalmente las razones para entrar a tratamiento o para suspender el consumo sin acudir a éste, los factores asociados al mantenimiento de la abstinencia y las dificultades y las amenazas de la misma. Se encontraron algunas diferencias significativas entre los grupos con y sin tratamiento, y también entre los hombres y las mujeres, especialmente en lo que se refiere a los factores asociados al mantenimiento de la recuperación. Sin embargo en ambos casos los vínculos familiares y afectivos –el ‘capital social’- aparecen como el factor de mayor importancia en la decisión de parar el consumo en todos los grupos. Por otra parte, el compromiso con las metas y el proyecto de vida personal son los motivos que estimulan el mantenimiento de la abstención o del consumo moderado, elementos que evidencian el paso progresivo de procesos cognitivos y emocionales con referentes externos a procesos en los que se privilegian los referentes de tipo interno y asociados al logro personal


This study examines the concept of natural recovery (without formal treatment) from problems associated with alcohol, marijuana, cocaine and heroin abuse, each one alone or in any combination. Two groups of males (40 Ss between 18 and 60 years of age) and two groups of females (19 Ss between 18 and 55 years of age) with at least one year of abstinence were studied. The main issues considered were: reason for attending treatment or ceasing the use of substances, factors related to maintenance of abstinence, and difficulties and threats associated with abstinence. Several significant differences were found between groups with and without treatment, as well as between males and females, particularly regarding factors related to the maintenance of abstinence. In both cases family and affective links appear as the most relevant factors in the decision to stop using substances. On the other hand, commitment to one’s goals and life project are the principal motives for maintaining abstinence or moderate consumption. This reflects the progressive transition from cognitive and emotional processes with external referents to processes with internal referents, associated with personal achievement


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Convalescença , Resultado do Tratamento , Inquéritos e Questionários
9.
Amino Acids ; 32(3): 323-32, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17021653

RESUMO

Nefopam (NEF) is a known analgesic that has recently been shown to be effective in controlling both neuropathic pain and convulsions in rodents. In this study we compared nefopam to carbamazepine (CBZ), a reference antiepileptic drug (AED), for their ability to protect cerebellar neuronal cultures from neurodegeneration induced by veratridine (VTD). Furthermore, we tested nefopam for protection against both, maximal electroshock-induced seizures (MES), and isoniazid-induced seizures in mice. Both NEF and CBZ were effective in preventing both signs of excitotoxicity and neurodegeneration following exposure of cultures to 5 microM veratridine for 30 min and 24 h, respectively. Concentrations providing full neuroprotection were 500 microM CBZ and 50 microM NEF, while the concentration providing 50% neuroprotection was 200 microM for CBZ and 20 microM for NEF. Neither NEF nor CBZ reduced excitotoxicity following direct exposure of cultures to glutamate, but CBZ failed to reduce increases in intracellular calcium following stimulation of L-type voltage sensitive calcium channels. In vivo, NEF (20 mg/kg i.p.) significantly reduced MES and fully prevented MES-induced terminal clonus (TC). In comparison, NEF was significantly more effective than CBZ in preventing MES, although both drugs were equally effective against MES-induced TC. Furthermore, nefopam provided protection against isoniazid-induced seizures at doses similar to those protecting against MES.


Assuntos
Analgésicos não Narcóticos/farmacologia , Anticonvulsivantes/farmacologia , Antituberculosos/toxicidade , Carbamazepina/farmacologia , Eletrochoque/efeitos adversos , Isoniazida/toxicidade , Nefopam/farmacologia , Fármacos Neuroprotetores/farmacologia , Convulsões/prevenção & controle , Veratridina/toxicidade , Animais , Canais de Cálcio Tipo L , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , Cerebelo/metabolismo , Cerebelo/patologia , Relação Dose-Resposta a Droga , Ácido Glutâmico/farmacologia , Masculino , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Convulsões/induzido quimicamente , Convulsões/metabolismo , Convulsões/patologia
10.
Adicciones (Palma de Mallorca) ; 13(1): 81-88, ene. 2001. tab
Artigo em Es | IBECS | ID: ibc-8396

RESUMO

Confrontado a la necesidad de llevar a cabo estudios epidemiológicos sobre consumo de drogas que superaran las deficiencias y los costos de los métodos convencionales, el Programa Presidencial RUMBOS y la Comisión Nacional de investigación en drogas, de Colombia, decidieron hacer una convocatoria a todos los jóvenes del país con edades entre los 10 y los 24 años para que contestaran una encuesta de siete preguntas. De esta manera se obtuvieron más de 305.000 respuestas. La riqueza de los datos llevó a los investigadores a emplear un análisis de regresión logística, cuyos resultados se presentan aquí, señalando las ventajas de emplear métodos estadísticos sofisticados con datos simples (AU)


Assuntos
Adolescente , Adulto , Feminino , Masculino , Criança , Humanos , Dependência de Heroína/epidemiologia , Transtornos Relacionados ao Uso de Cocaína/epidemiologia , N-Metil-3,4-Metilenodioxianfetamina/efeitos adversos , Fatores Socioeconômicos , Colômbia/epidemiologia , Modelos Logísticos , Tabagismo/epidemiologia , Alcoolismo/epidemiologia
12.
Porto Alegre; Artmed; 4 ed; 2000. 391 p.
Monografia em Português | LILACS, EMS-Acervo | ID: lil-625797

Assuntos
Educação , Ensino
13.
Porto Alegre; Artmed; 4 ed; 2000. 391 p.
Monografia em Português | Sec. Munic. Saúde SP, EMS-Acervo | ID: sms-394

Assuntos
Educação , Ensino
14.
Semin Arthritis Rheum ; 27(4): 226-44, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9514128

RESUMO

OBJECTIVES: To analyze the usefulness of the new azoles for the treatment of fungal osteoarticular infections, and to report three cases of fungal knee arthritis treated with fluconazole in our unit. METHODS: The medical literature was reviewed for all cases of osteoarticular infection caused by fungi and treated with fluconazole or itraconazole registered in the MedLine Silver Platter database from 1972 to 1997. RESULTS: The total number of patients included in this review was 56; 19 were treated with fluconazole and 37 with itraconazole. The most frequent causative agents implicated were fungi of the genuses Candida and Aspergillus. There were eight therapeutic failures, and there were no statistically different findings among the patients in terms of their health status. Adverse effects were unusual. CONCLUSIONS: Controlled studies are necessary to establish the true role of the new azole drugs in the treatment of fungal osteoarticular infections, but they seem to be a promising therapeutic option.


Assuntos
Antifúngicos/uso terapêutico , Artrite Infecciosa/tratamento farmacológico , Candidíase , Criptococose , Fluconazol/uso terapêutico , Osteoartrite/tratamento farmacológico , Osteoartrite/microbiologia , Adulto , Artrite Infecciosa/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade
15.
J Subst Abuse Treat ; 10(3): 317-21, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8315705

RESUMO

This paper presents the experience of "La Casa" Programme, a center of the University of Los Andes (Bogotá, Colombia) aimed at prevention, treatment, and research in the fields of drug addiction and AIDS. The multimodal strategy at "La Casa", ambulatory and almost free of charge, has constituted a unique approach in Colombia. The country has a heavy and specific drug consumption problem: in the last ten years the number of regular consumers of a mixture of alcohol, coca paste ("basuco")/cocaine and marihuana has increased to almost 500,000 people; state facilities and human resources are scarce, thus the importance of an appropriate use of them and search for alternatives.


Assuntos
Assistência Ambulatorial , Comparação Transcultural , Psicotrópicos , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adolescente , Adulto , Cocaína , Colômbia , Comportamento Compulsivo/psicologia , Comportamento Compulsivo/reabilitação , Feminino , Seguimentos , Humanos , Masculino , Avaliação de Processos e Resultados em Cuidados de Saúde , Aceitação pelo Paciente de Cuidados de Saúde , Transtornos Relacionados ao Uso de Substâncias/psicologia
16.
Int J Addict ; 28(5): 389-98, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8478153

RESUMO

A global, tridimensional, and comprehensive model for the drug problem is presented. On a flat matrix with five components (growing, production, processing, traffic/distribution, and consumption) and seven dimensions (individual, family, restricted group, neighborhood, city/region, national, and international), six different perspectives are employed (psychobiological, social/political, economics, legal, historical/cultural, and geographical). Each psychoactive substance may be analyzed separately.


Assuntos
Drogas Ilícitas , Cooperação Internacional , Psicotrópicos , Transtornos Relacionados ao Uso de Substâncias/prevenção & controle , Controle de Medicamentos e Entorpecentes , Humanos , Modelos Teóricos , Meio Social , Detecção do Abuso de Substâncias
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...