13 research outputs found
Pesquisa anatômica sobre a ramificação e a disposição das artérias e veias da placenta de bovinos azebuados
The branching and the arrangement of the placental arteries and veins of 20 Nelore bovines were studied. An anastomosies between the 2 arteries in the funiculus umbilicalis appeared in 75% of the cases (70% single and 5% double). The types of vasculo-cotyledonary distribution were based on the arrangements of arteries and veins and on their relationship with thecotyledons. A cotyledon supplied by a single artery is drained by multiple veins, and in a few cases the arteries and veins supplied and drained, respectively, cotyledons of the pregnant and non-pregnant uterine horns.A ramificação e a disposição das artérias e veias placentárias foram estudadas em 20 vacas da raça Nelore. Uma anastomose entre as duas artérias do funÃculo umbilical aparece em 75% dos casos (70% única e 5% dupla). Os tipos de distribuição i/ásculo-cotiledonário foram baseados nos arranjos das artérias e veias nas suas relações com os cotilédones. Um cotilédone suprido por uma única artéria é drenado por múltiplas veias e, em poucos casos, as artérias e veias suprem e drenam respectivamente cotilédones dos cornos uterinos gestante e não gestante
Canonical WNT signaling regulates development of bovine embryos to the blastocyst stage
Objectives were to evaluate the role of canonical WNT signaling in development of the preimplantation embryo. Signaling was activated with 2-Amino-4-(3,4-(methylenedioxy)benzylamino)-6-(3-methoxyphenyl)pyrimidine (AMBMP) and inhibited with Dickkopf-related protein 1 (DKK1). Treatment of bovine embryos with AMBMP at day 5 after insemination decreased development to the blastocyst stage at day 7 and reduced numbers of trophectoderm and inner cell mass cells. At high concentrations, AMBMP caused disorganization of the inner cell mass. DKK1 blocked actions of AMBMP but did not affect development in the absence of AMBMP. Examination of gene expression in day 6 morulae by microarray revealed expression of 16 WNT genes and other genes involved in WNT signaling; differences in relative expression were confirmed by PCR for 7 genes. In conclusion, the preimplantation embryo possesses a functional WNT signaling system and activation of the canonical pathway can inhibit embryonic development
PerÃodos de digestão enzimática para o resgate de folÃculos pré-antrais em ovários de fetos bovinos Periods of enzimatic digestion for rescueing preantral follicles from fetal bovine ovaries
O presente experimento foi delineado com o objetivo de determinar a influência de diferentes perÃodos de digestão enzimática nos ovários de fetos bovinos, sobre o número total de folÃculos pré-antrais resgatados e o número de folÃculos resgatados em cada estágio de desenvolvimento. A presença da membrana basal, envolvendo o complexo formado pelas células da granulosa e o oócito, foi observada através de um estudo histológico, o que permitiu avaliar a integridade morfológica dos folÃculos pré-antrais isolados. Para isso, ovários de fetos bovinos, entre 150 e 270 dias de gestação, foram obtidos em frigorÃfico. No laboratório, os ovários foram seccionados em vários fragmentos com uma tesoura cirúrgica e dissociados com pipetas de Pasteur, com diâmetros aproximados de 1000 e 500mim. Após este processo, os fragmentos foram submetidos à digestão enzimática com colagenase em uma concentração de 200UI/ml de TCM199 modificado, por perÃodos de 20, 30 ou 40 minutos. Os resultados obtidos com esta técnica permitiram determinar que o número de folÃculos pré-antrais isolados, assim como, os estágios de desen- volvimento em que esses folÃculos encontravam-se no momento do isolamento, são similares nos três perÃodos de incubação enzimática. A estrutura morfológica desses folÃculos, formada pelo oócito, células da granulosa e membrana basal, manteve-se intacta após o isolamento nos três perÃodos de digestão enzimática.The objective of this experiment was to determine the efficiency and the effect of different enzymatic digestion periods on the number and developmental stages of preantral follicles isolated from bovine fetal ovaries. The presence of basal membrane, surrounding granulosa cells-oocyte complex, was observed, after digestion, through histologycal study. For this, ovaries from bovine fetues, were collected in slaughterhouses, between 150 and 270 days of pregnancy. In the laboratory, the ovaries were cut into several fragments with surgical scissors and dissociated with Pasteur pipette, having either 1000 or 500mum diameter. After these steps, the fragments were submitted to an enzymatic digestion with collagenase in a concentration of 200IU/ml of modified TCM 199, for periods of 20, 30 or 40 minutes. The results showed that determined the total number and the quantity of the different developmental stages of isolated preantral follicles were similar in the three different periods of enzymatic digestion. The histological analyses demonstrated that the enzymatic digestion periods did not affect the morphological structure of the follicles
Effects of resistance exercise combined with essential amino acid supplementation and energy deficit on markers of skeletal muscle atrophy and regeneration during bed rest and active recovery
Spaceflight and bed rest (BR) lead to muscle atrophy. This study assessed the effect of essential amino acid (EAA) supplementation and resistance training with decreased energy intake on molecular changes in skeletal muscle after 28-day BR and 14-day recovery. Thirty-one men (31-55 years) subjected to an 8 ± 6% energy deficit were randomized to receive EAA without resistance training (AA, n = 7), or EAA 3 h after (RT, n = 12) or 5 min before (AART, n = 12) resistance training. During BR, myostatin transcript levels increased twofold in the AA group. During recovery, insulin-like growth factor-1 (IGF-1) mRNA increased in all groups, whereas Pax7, MyoD, myogenin, and MRF4 transcripts increased in AA only (all P < 0.05). MAFbx transcripts decreased twofold with AA and RT. Satellite cells did not change during BR or recovery. This suggests that EAA alone is the least protective countermeasure to muscle loss, and several molecular mechanisms are proposed by which exercise attenuates muscle atrophy during BR with energy deficit
Prostaglandin F2alpha- and FAS-activating antibody-induced regression of the corpus luteum involves caspase-8 and is defective in caspase-3 deficient mice
We recently demonstrated that
caspase
-3 is important for apoptosis during spontaneous involution of the corpus luteum (CL). These studies tested if prostaglandin F
2α
(PGF
2α
) or FAS regulated luteal regression, utilize a
caspase
-3 dependent pathway to execute luteal cell apoptosis, and if the two receptors work via independent or potentially shared intracellular signaling components/pathways to activate
caspase
-3. Wild-type (WT) or
caspase
-3 deficient female mice, 25–26 days old, were given 10 IU equine chorionic gonadotropin (eCG) intraperitoneally (IP) followed by 10 IU human chorionic gonadotropin (hCG) IP 46 h later to synchronize ovulation. The animals were then injected with IgG (2 micrograms, i.v.), the FAS-activating antibody Jo2 (2 micrograms, i.v.), or PGF
2α
(10 micrograms, i.p.) at 24 or 48 h post-ovulation. Ovaries from each group were collected 8 h later for assessment of active
caspase
-3 enzyme and apoptosis (measured by the TUNEL assay) in the CL. Regardless of genotype or treatment, CL in ovaries collected from mice injected 24 h after ovulation showed no evidence of active
caspase
-3 or apoptosis. However, PGF
2α
or Jo2 at 48 h post-ovulation and collected 8 h later induced
caspase
-3 activation in 13.2 ± 1.8% and 13.7 ± 2.2 % of the cells, respectively and resulted in 16.35 ± 0.7% (PGF
2α
) and 14.3 ± 2.5% TUNEL-positive cells when compared to 1.48 ± 0.8% of cells CL in IgG treated controls. In contrast, CL in ovaries collected from
caspase
-3 deficient mice whether treated with PGF
2α
, Jo2, or control IgG at 48 h post-ovulation showed little evidence of active
caspase
-3 or apoptosis. CL of WT mice treated with Jo2 at 48 h post-ovulation had an 8-fold increase in the activity of
caspase
-8, an activator of
caspase
-3 that is coupled to the FAS death receptor. Somewhat unexpectedly, however, treatment of WT mice with PGF
2α
at 48 h post-ovulation resulted in a 22-fold increase in
caspase
-8 activity in the CL, despite the fact that the receptor for PGF
2α
has not been shown to be directly coupled to
caspase
-8 recruitment and activation. We hypothesize that PGF
2α
initiates luteolysis
in vivo
, at least in part, by increasing the bioactivity or bioavailability of cytokines, such as FasL and that multiple endocrine factors work in concert to activate
caspase
-3-driven apoptosis during luteolysis
Dermcidin exerts its oncogenic effects in breast cancer via modulation of ERBB signaling
Background: We previously identified dermicidin (DCD), which encodes a growth and survival factor, as a gene amplified and overexpressed in a subset of breast tumors. Patients with DCD-positive breast cancer have worse prognostic features. We therefore searched for specific molecular signatures in DCD-positive breast carcinomas from patients and representative cell lines. Methods: DCD expression was evaluated by qRT-PCR, immunohistochemical and immunoblot assays in normal and neoplastic tissues and cell lines. To investigate the role of DCD in breast tumorigenesis, we analyzed the consequences of its downregulation in human breast cancer cell lines using three specific shRNA lentiviral vectors. Genes up- and down-regulated by DCD were identified using Affymetrix microarray and analyzed by MetaCore Platform. Results: We identified DCD splice variant (DCD-SV) that is co-expressed with DCD in primary invasive breast carcinomas and in other tissue types and cell lines. DCD expression in breast tumors from patients with clinical follow up data correlated with high histological grade, HER2 amplification and luminal subtype. We found that loss of DCD expression led to reduced cell proliferation, resistance to apoptosis, and suppressed tumorigenesis in immunodeficient mice. Network analysis of gene expression data revealed perturbed ERBB signaling following DCD shRNA expression including changes in the expression of ERBB receptors and their ligands. Conclusions: These findings imply that DCD promotes breast tumorigenesis via modulation of ERBB signaling pathways. As ERBB signaling is also important for neural survival, HER2+ breast tumors may highjack DCD’s neural survival-promoting functions to promote tumorigenesis. Electronic supplementary material The online version of this article (doi:10.1186/s12885-015-1022-6) contains supplementary material, which is available to authorized users