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1.
J Affect Disord ; 2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39079604

RESUMO

BACKGROUND: Group differences in longitudinal patterns of child and adolescent depressive symptoms are commonly observed. However, the implications for adult mental health are unclear. This study presents a systematic review of child and adolescent depressive trajectory research and meta-analysis of their longitudinal effects on adult depressive symptoms and disorders. METHODS: A systematic search identified 12 longitudinal studies (12 cohorts, N = 35,058) that were harmonized to identify common symptom trajectories prior to age 18 years. Examination of follow-up in the same groups was made to estimate longitudinal associations with adult depressive symptoms and disorders, using random effects meta-analyses. RESULTS: The included studies identified Low (70.3 %), Moderate (17.9 %), High (9.5 %), Increasing (9.5 %) and Decreasing (5.1 %) symptom trajectories. These trajectories were found to predict variation in symptoms and disorders in adulthood: Low, Dx = 4.5 %, 95 % CI 2.7-6.8 %, Sx = 8.33, SD = 6.30; Moderate, Dx = 20.9 %, CI 11.9-31.5 % - Sx = 18.13, SD = 3.38; High, Dx = 34.4 % CI 17.2-54.0 % - Sx = 38.80, SD = 7.75; Increasing, Dx = 38.3 %, CI 12.7-67.5 % - Sx = 24.73, SD = 18.64; Decreasing, Dx = 15.4 %, CI 10.5-20.9 % - Sx = 17.00, SD = 12.18. LIMITATIONS: Confidence intervals are wide for some trajectory effects. There was significant between-cohort heterogeneity in predictive effects for High trajectories, suggesting the need for further research to identify characteristics influencing variation. CONCLUSION: Low symptom trajectories forecast lower adult depression symptoms and disorders. Programs effectively targeting reductions in Moderate, High, Increasing and Decreasing trajectories will likely prevent problems in early adulthood.

2.
Bull Environ Contam Toxicol ; 97(4): 447-8, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27373345
3.
Theriogenology ; 78(4): 753-8, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22541318

RESUMO

To determine if postpartum subclinical infection occurs in sows, a novel device was used to diagnose such bacterial contamination of the vagina. The device was based on the measurement of biogenic amines by ion mobility spectrometry (IMS). The device is portable and results are obtained within 1 min. Vaginal swabs were taken from 449 sows before first-estrus insemination and 133 (29.6%) had elevated biogenic amines and were considered positives. Sixty-one percent of the sows became pregnant following post-weaning first estrus insemination. Positive scores had no apparent effect on fertility rate which was 64%. Of the sows that became pregnant, 197 (69.1%) were diagnosed as "negative" and 88 (30.9%) were "positive", of which 37 received treatment with antibiotics and were termed "positive treated". The average live-born piglets litter size of the "positives" was 10.02 which was significantly lower (P = 0.031) than the "negative" sows (11.06) while "positive treated" sow average litter size was close to the "negative" (10.56). In conclusion, it was demonstrated that subclinical anterior-vaginal bacterial contamination in lactating sows about 2 wks postpartum is a condition that affects sow litter number and could be determined by the measurement of vaginal biogenic amines with IMS.


Assuntos
Infecções Bacterianas/diagnóstico , Aminas Biogênicas/análise , Análise Espectral/métodos , Doenças dos Suínos/diagnóstico , Vagina/microbiologia , Animais , Infecções Assintomáticas , Calibragem , Feminino , Íons/análise , Íons/química , Tamanho da Ninhada de Vivíparos/fisiologia , Movimento/fisiologia , Período Pós-Parto , Gravidez , Análise Espectral/normas , Análise Espectral/veterinária , Suínos , Vaginose Bacteriana/diagnóstico
4.
Theriogenology ; 69(6): 673-80, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18242683

RESUMO

We monitored fecal testosterone and progesterone levels in 26 adult ibexes (17 males, 9 females) in a captive herd Nubian ibex held on 250 ha tract to test if testosterone is associated with dominance. The ibexes were observed over a 20-month period, and including two mating seasons, during which time we collected fecal samples twice during early gestation and postpartum intervals and once during lactation and pre-rut season intervals. The social hierarchy was linear with age in adult males and nearly linear in adult females. High ranking males were in solitude, but females were aggregated with the kids in the presence of a dominant female. The testosterone concentration in the males in the pre-rut (211+/-12 ng/g; N=13; dominant male 296 ng/g) was significant higher than other seasons (P<0.05). High testosterone in dominant male at pre-rut was associated with a decrease in confrontations. The individuals with the highest average testosterone concentrations were the dominant male and female (166+/-82 ng/g; 130+/-32 ng/g, N=6, respectively). In females, testosterone was highest in during the post-partum interval and was associated with an increase in aggression. The three highest fertile ranking females had higher testosterone (119+/-14 ng/g vs. 92+/-18 ng/g, P<0.05) than the four subordinate females. The sex ratio of the offspring was 8M/3F for the three older females and 5M/7F for the younger females. In early gestation period, females with only male fetuses had higher testosterone than other gravidities (119+/-14 ng/g, N=6 vs. 91+/-18 ng/g, N=7, P<0.01). Progesterone was significantly higher in the eight multiparous pregnancies than in those with the five singletons (210+/-19 ng/g vs. 186+/-12 ng/g, P<0.02). We conclude that high testosterone in females is associated with an increase in aggressive confrontations in early- and mid-lactation. In contrast, increased testosterone during pre-rut in males is associated with fewer confrontations. In addition, the data support the hypothesis that higher ranking, older dimorphic female ungulates have higher testosterone concentrations and have more male births than subordinate females.


Assuntos
Agressão/fisiologia , Fezes/química , Cabras/fisiologia , Razão de Masculinidade , Predomínio Social , Testosterona/análise , Animais , Feminino , Lactação/fisiologia , Masculino , Paridade , Gravidez
5.
Gen Comp Endocrinol ; 151(1): 122-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17289044

RESUMO

The steroidal hormonal profiles of two sympatric species of desert snails, Sphincterochila zonata and Sphincterochila prophetarium were determined at three ecophysiological-behavior stages, i.e., aestivation, cryptobiosis, and active-feeding phases. Live snails were collected in their natural habitat every month for 13 months, the corpi removed and extracted with organic solvents and the progesterone, testosterone, and estrogen concentrations determined by radioimmunoassay. In both these hermaphroditic species during aestivation, a peak of testosterone followed by a peak of estrogen was observed. During the brief active intervals, minor peaks of estrogen were also observed but these were much lower than seen during aestivation. Although the two species have different microhabitats during aestivation, there was little difference in the hormonal profile, although S. prophetarum had about two fold higher progesterone concentration than S. zonata.


Assuntos
Estrogênios/análise , Progesterona/análise , Caramujos/metabolismo , Testosterona/análise , Animais , Clima Desértico , Ecossistema , Feminino , Israel , Masculino , Radioimunoensaio , Estações do Ano , Caramujos/crescimento & desenvolvimento
6.
Biochem J ; 357(Pt 2): 489-95, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11439099

RESUMO

The control of cell-cell communication through gap junctions is thought to be crucial in normal tissue function and during various stages of tumorigenesis. However, few natural regulators of gap junctions have been found. We show here that increasing the activity of ornithine decarboxylase, or adding polyamines to the outside of cells, increases the level of gap junction communication between various epithelial cells. Conversely, reduction of ornithine decarboxylase activity decreases the level of gap junction communication. This regulation is dependent upon the expression of connexin 43 (Cx43 or Cxalpha1), which is a major connexin expressed in many different cell types, and involves an increase in Cx43 and its cellular re-distribution.


Assuntos
Comunicação Celular/fisiologia , Conexina 43/metabolismo , Junções Comunicantes/fisiologia , Queratinócitos/fisiologia , Ornitina Descarboxilase/metabolismo , Putrescina/farmacologia , Espermidina/farmacologia , Animais , Butadienos/farmacologia , Comunicação Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Conexina 43/deficiência , Conexina 43/genética , Cruzamentos Genéticos , Eflornitina/farmacologia , Embrião de Mamíferos , Inibidores Enzimáticos/farmacologia , Junções Comunicantes/efeitos dos fármacos , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Camundongos , Camundongos Knockout , Nitrilas/farmacologia , Ornitina Descarboxilase/genética , Proteínas Recombinantes/metabolismo , Pele/citologia , Pele/embriologia , Fenômenos Fisiológicos da Pele
7.
Semin Reprod Med ; 19(1): 87-96, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11394209

RESUMO

Bovine myometrium and cervix contain luteinizing hormone/human chorionic gonadotropin (LH/hCG) binding sites, LH receptor (LH-R) messenger RNA (mRNA), and LH-R protein. Expression of LH-R is dependent on the stage of the cycle. LH-R expression is high during the luteal phase but weak during the follicular phase. In both myometrium and cervix, LH activates both the adenylate cyclase and phospholipase C pathways, and the effect of LH on both pathways at each stage of the cycle is correlated with the amount of LH-R present in the tissue. Because activation of cyclic AMP (cAMP) is associated with myometrial quiescence, we suggest that LH activation of uterine cAMP could serve to keep the uterus quiescent during the luteal phase. On the other hand, in the uterine vein LH-R mRNA and LH-R are maximal during preestrus/estrus as opposed to the luteal phase. In the uterine vein, LH increases the expression of cyclooxygenase and production of both prostaglandin E2 (PGE2) and PGF2 alpha. Because PGF2 alpha is the physiological luteolytic signal in the cow, we suggest that this increase in prostaglandin production by the uterine vein is part of the physiological events leading to luteolysis. In addition to uterine LH-R, the bovine cervix at preestrus/estrus has high levels of follicle-stimulating hormone receptor (FSH-R) and its corresponding mRNA. As with LH-R, activation of FSH-R by FSH is associated with activation of a G protein-coupled receptor family that mediates the cAMP and inositol phosphate signaling pathways. Activation of these signaling pathways is associated with an increase in the expression of cyclooxygenase and production of PGE2. Because expression of the FSH receptor was maximal at the time of the FSH peak in the blood, we suggest a physiological role for FSH in the cervix relaxation and opening at estrus.


Assuntos
Bovinos/fisiologia , Colo do Útero/química , Miométrio/química , Receptores do FSH/fisiologia , Receptores do LH/fisiologia , Útero/irrigação sanguínea , Adenilil Ciclases/metabolismo , Animais , Colo do Útero/fisiologia , Feminino , Fosfatos de Inositol/metabolismo , Hormônio Luteinizante/farmacologia , Miométrio/fisiologia , Prostaglandina-Endoperóxido Sintases/metabolismo
8.
Reprod Biol ; 1(2): 13-32, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14666165

RESUMO

Bovine endometrium contains LH/hCG binding sites and LH increases endometrial production of prostaglandin H synthase-2 (PGHS-2) and prostaglandin synthesis. This study showed that uterine endometrium contained both LH receptor mRNA transcript and a 93-kDa immunoreactive protein that bound to anti-rat LH receptor antibody. LH receptor and its mRNA were expressed maximally in the endometrium of cows from the luteal phase compared to the follicular phase of the estrous cycle. Furthermore, there was a response shown when incubation of endometrial minces from both pre-estrus/estrus and luteal phase (but not post-ovulatory phase) with LH or oxytocin (20 ng/ml) that resulted in a significant (p<0.02) increase in cAMP and total inositol phosphates. When Day 15 cows were injected i.v. with 3000 units hCG, the increase in peripheral 13,14-dihydro-15-keto PGF(2alpha) was 2.5-fold higher than saline controls or oxytocin. We conclude that LH stimulates endometrial cAMP and total inositol phosphates which results in increased formation of uterine PGHS-2 similar to LH effect on ovarian PGHS-2. The increased 13,14-dihydro-15-keto PGF(2alpha) production induced in vivo by injections of hCG indicates that LH may have a reinforcing role in luteolysis.


Assuntos
Bovinos , Gonadotropina Coriônica/administração & dosagem , Dinoprosta/análogos & derivados , Endométrio/química , Hormônio Luteinizante/administração & dosagem , RNA Mensageiro/análise , Receptores do LH/genética , Animais , Sequência de Bases , Western Blotting , AMP Cíclico/metabolismo , AMP Cíclico/farmacologia , Ciclo-Oxigenase 2 , Dinoprosta/análise , Dinoprosta/biossíntese , Feminino , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/genética , Expressão Gênica/efeitos dos fármacos , Fosfatos de Inositol/metabolismo , Isoenzimas/análise , Dados de Sequência Molecular , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ocitocina/farmacologia , Prostaglandina-Endoperóxido Sintases/análise , Prostaglandinas/metabolismo , RNA Mensageiro/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência , Fosfolipases Tipo C/metabolismo , Útero/efeitos dos fármacos , Útero/metabolismo
9.
Mol Reprod Dev ; 56(2 Suppl): 306-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10824991

RESUMO

Transgenic bovine sperm were produced by restriction enzyme mediated insertion (REMI). REMI utilizes lipofection of linearized pEGFP and the corresponding restriction enzyme for integration into the sperm genomic DNA. The transgenic sperm were used in IVF to produce morula expressing GFP. When transgenic sperm were used for AI in two cows, the resultant calves expressed the exogenous DNA in their lymphocytes as determined by (a) PCR and RT-PCR; (b) specific emission of green fluorescence by GFP; and (c) Southern blot analysis. Data demonstrate that REMI is an efficient method for the production of transgenic sperm and corresponding offspring by AI or embryos by IVF.


Assuntos
Animais Geneticamente Modificados/genética , DNA/genética , Técnicas de Transferência de Genes , Espermatozoides , Animais , Animais Geneticamente Modificados/metabolismo , Animais Recém-Nascidos , Southern Blotting , Bovinos , DNA/metabolismo , Enzimas de Restrição do DNA/metabolismo , Embrião de Mamíferos/metabolismo , Fertilização in vitro , Proteínas de Fluorescência Verde , Técnicas In Vitro , Inseminação Artificial , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
10.
Res Vet Sci ; 67(2): 121-3, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10502479

RESUMO

Recently, we reported that intraocular pressure (IOP) in juvenile male lions (Panthera leo) is significantly higher than in juvenile lionesses. Whilst we could not ascertain the basis for this gender-related difference, we suspected that they were the result of fluctuations in levels of sex hormones. Because 19 of the 22 lions described in our previous report had to be re-anaesthetized, we repeated tonometry in these animals, to try and correlate between IOP and the levels of progesterone, oestrogen and/or testosterone. Based on elevated (>5 ng ml(-1)) levels of progesterone, lionesses were divided into a luteal (n = 8) and a non-luteal (n = 13) group. In the luteal group, mean IOP was 27.07+/-2.15 mm Hg, significantly (P = 0.001) higher than in the non-luteal group (21.61+/-2.70 mm Hg). Oestrogen, testosterone, anesthesia and age had no significant effect on IOP. It is suggested that elevated progesterone levels associated with the luteal phase in lionesses cause increased resistance to aqueous humor outflow, leading to IOP elevation. Similar ocular hypertension has been observed in rabbits following exogenous progesterone application, but this is the first report on the hypertensive effect of endogenous progesterone on IOP.


Assuntos
Pressão Intraocular/fisiologia , Leões/fisiologia , Progesterona/sangue , Animais , Estrogênios/sangue , Feminino , Masculino , Coelhos , Caracteres Sexuais , Testosterona/sangue
11.
Theriogenology ; 50(1): 101-7, 1998 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10734478

RESUMO

In a survey on pregnancy rate and embryonic losses in dairy cattle on 6 Israeli farms, cows (n = 78) were divided into 3 groups on the basis of ultrasonography at 21 d post insemination; pregnancy diagnosis at 40 to 50 d post insemination and blood progesterone (P4) levels at 21 d. The groups were either pregnant (P4 level > 1.0 ng/ mL); not pregnant (P4 < 0.5 ng/mL), or showed early embryo loss (P4 > 1.0 ng/mL and the presence of an embryonic vesicle on D 21 but later returned to estrus or were found not pregnant on D 40 to 50). On the day of insemination, peripheral estrogen was significantly higher (P < 0.05) in the early embryo loss group (15.3 +/- 1.1 pg/mL, n = 27) than in pregnant (9.4 +/- 0.6 pg/mL, n = 26) or not pregnant (9.6 +/- 0.7 pg/mL, n = 25) group. The cows on 3 farms which were fed 1 to 2 kg/d of vetch (Vicia sativa), an estrogenic legume, had higher estrogen concentrations on the day of insemination than cows (2 farms) fed other legumes (13.7 +/- 0.64, n = 58 vs 10.7 +/- 0.8 pg/mL, n = 42; P < 0.01). On one of the 3 farms, vetch was replaced with alfalfa after the first year. Following the cessation of vetch feeding the estrogen concentrations in the blood decreased from 32 +/- 5 pg/mL to 14 +/- 2 pg/mL (n = 9). These data suggest that high peripheral estrogen on the day of insemination is associated with early embryonic loss. These data also indicate that estrogen concentrations on the day of insemination can be influenced by diet.


Assuntos
Aborto Animal , Estrogênios/sangue , Inseminação Artificial/veterinária , Ração Animal , Animais , Bovinos , Feminino , Idade Gestacional , Israel , Gravidez , Taxa de Gravidez , Estudos Prospectivos
12.
Endocrinology ; 138(11): 4844-51, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9348214

RESUMO

We have previously reported that bovine endometrium contains LH/human CG binding receptors and LH induces cyclooxygenase and prostaglandin production in the bovine endometrium. The present study investigated 1) whether bovine uterine vein and artery contain LH receptor messenger RNA (mRNA) and receptor protein and 2) whether LH can regulate the formation of vasoactive eicosanoids by the uterine vein. The uterine vein endothelium, but not the uterine artery, contained LH receptor mRNA transcript essentially identical to that found in the bovine corpus luteum. The uterine vein endothelium also contained a 95-kDa immunoreactive receptor protein that bound to rat anti-LH receptor antibody in Western blots. The LH receptor mRNA and LH receptor were maximally expressed in the uterine vein from cows in proestrus/estrus compared with cows in luteal or postovulatory phases. Incubation of endothelial minces of uterine vein with LH resulted in a 2-fold increase in cyclooxygenase concentration as determined by Western blot using an antibody to ram seminal vesicle cyclooxygenase. The increase in cyclooxygenase was maximal in cows in proestrus/estrus compared with postovulatory and luteal phase cows. Incubation of proestrous/estrous uterine vein or artery minces with LH or mellitin (a phospholipase A2 stimulator) caused increased production of eicosanoids. In the uterine vein, LH caused a significant increase in both PGF2alpha (basal 4.1 +/- 0.4 vs. 5.7 +/- 0.4 ng/100 mg x 6 h, P < 0.01; N = 9 cows) and PGE2 (basal 5.7 +/- 0.3 vs. 7.7 +/- 0.8 ng/100 mg x 6 h, P < 0.01; N = 6 cows) but had no effect on prostaglandin production by the artery. Mellitin increased PGF2alpha production by both uterine vein and artery minces but had no effect on PGE2 production in either tissue. Addition of steroids (progesterone, estradiol) or cytokines (tumor necrosis factor-alpha, IL-6) to the uterine vascular tissues had essentially no effect on prostanoid production. In summary, bovine uterine vein from proestrous/estrous cows expressed the LH receptor and its mRNA. Expression of the receptor may have physiological significance as LH induces cyclooxygenase and increases prostaglandin release in the uterine vein. The maximal stimulation of the receptor and its mRNA at proestrus/ estrus may serve to increase the amounts of prostanoids reaching the regressing corpus luteum either directly by increasing prostanoid production or indirectly by increasing the blood flow to the ovary.


Assuntos
Prostaglandinas/biossíntese , RNA Mensageiro/metabolismo , Receptores do LH/genética , Receptores do LH/metabolismo , Útero/irrigação sanguínea , Veias/metabolismo , Animais , Sequência de Bases , Bovinos , Dinoprosta/biossíntese , Dinoprostona/biossíntese , Indução Enzimática/fisiologia , Feminino , Hormônio Luteinizante/fisiologia , Meliteno/farmacologia , Dados de Sequência Molecular , Prostaglandina-Endoperóxido Sintases/metabolismo , Ratos , Receptores do LH/fisiologia
13.
Theriogenology ; 48(3): 341-52, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16728132

RESUMO

A unilateral cryptorchid bull stationed in an AI center for 3.5 yr was studied to determine if maintaining such a bull could be justified. The following parameters were determined: quantity and quality of the ejaculates, basal and stimulated plasma testosterone concentrations, and the histology and testosterone concentrations of the testicles. The bull produced 232 ejaculates of which 125 (53.8%) were immediately discarded; the rest (107 ejaculations) were processed into pellets. Two of the 107 frozen ejaculates (2%) were found to be of excellent quality, 37 were (34.5%) of good quality, 45 were (42%) of satisfactory quality and 23 were (21.5%) of poor quality. Treatment of the calf with GnRH and hCG at 4 and 5 mo of age did not initiate the descent of the retained testicle. Testosterone concentrations measured at 14 mo, after hCG stimulus, indicated that the bull had impaired steroidogenesis when compared with 2 control bull calves. Post mortem examination revealed a small left testicle in the inguinal canal and a normal right testicle as well as normal secondary sex glands. During the breeding period at the AI center, the bull's peripheral testosterone concentrations decreased from 2.2 to 0.95 ng/ml Testosterone concentrations in the parenchymal tissue of the scrotal testicle were higher than in the parenchyma of the retained testicle (98.2 vs 53.9 ng/g). In contrast, the epididymis of the scrotal testicle had a lower testosterone concentration than the epididymis of the retained testicle (10.8 vs 33. 0 ng/g). On histological examination no spermatozoa were found in the retained testicle, the Sertoli cells showed fat degeneration, and fibrotic tissue surrounded the tubuli seminiferi. No pathological changes were found in the normal scrotal testicle. In conclusion, no justification was found for maintaining such a bull in the AI center for breeding purposes.

14.
J Biol Chem ; 272(19): 12536-43, 1997 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-9139705

RESUMO

Ornithine decarboxylase (ODC) is the key initial enzyme in the biosynthesis of polyamines. Since polyamines have been shown to enhance protein kinase CK2 activity in vitro, ODC was overexpressed to examine the role of polyamines in CK2 regulation in vivo. Infection of Balb/MK cells with an ODC retrovirus to elevate ODC and polyamine levels increased overall protein phosphorylation as well as CK2 protein levels and enzyme activity in mimosine- or nocodazole- arrested cells. Immunofluorescence microscopy and enzyme analyses of subcellular fractions from ODC-overexpressing cells demonstrated translocation of CK2 from the cytoplasm to the nucleus with no apparent loss of cytoplasmic CK2 activity, suggesting polyamine activation of the remaining cytoplasmic enzyme. Similarly, K6/ODC transgenic mice exhibited higher ODC and CK2 enzyme activities than their normal littermates. ODC-immunostained cells in the transgenic skin also stained intensely for CK2 protein. Primary cultures of K6/ODC keratinocytes also exhibited increased ODC and CK2 enzyme activities compared with those from normal littermates. However, the addition of difluoromethylornithine, a specific ODC inhibitor, to the transgenic keratinocytes reduced both intracellular polyamine levels and CK2 enzyme activity. These results suggest that polyamines regulate the CK2 enzyme by affecting its cellular distribution as well as its enzyme activity and levels.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Ornitina Descarboxilase/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Caseína Quinase II , Células Cultivadas , Ativação Enzimática , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Nitrilas/metabolismo , Poliaminas/metabolismo , Compostos de Piridínio/metabolismo
15.
Reprod Fertil Dev ; 9(5): 525-30, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9418982

RESUMO

Prostaglandin E2 (PGE2) can cause softening of the bovine cervix at oestrus when receptors for oxytocin (OT) are maximally present, indicating a relationship between OT and PGE2 production. It was therefore determined whether OT can stimulate prostaglandin synthesis or induce cyclooxygenase expression in cervical external os segments obtained from pre-oestrous-oestrous cows. Tissues were minced and incubated (50-100 mg mL[-1] 6 h[-1]) in the presence of OT (10 ng mL[-1]), progesterone (P4) (5 ng mL[-1]) and/or indomethacin (5 microg mL[-1]). It was found that OT stimulated basal PGE2 (7.79+/-1.22 ng 100 mg[-1], mean+/-s.e.m.; n = 6) in external os segments from pre-oestrous-oestrous cows (P < 0.03), whereas P4 and indomethacin inhibited basal and OT-stimulated PGE2 production (P < 0.05). Basal prostaglandin F2alpha (PGF2alpha) production was minimal (<1 ng 100 mg[-1]) and OT had no effect on its production. Expression of cyclooxygenase was measured by Western blot analysis following incubation of the tissue (100 mg 1.5 mL[-1] 3 h[-1]) in the presence of OT (10 ng mL[-1]) and in the presence of P4 (5 ng mL[-1]). It was found that OT stimulated the induction of cyclooxygenase II (79+/-10%; n = 7, P < 0.05). In contrast, P4 inhibited the basal expression of this enzyme (-40+/-5%, n = 7, P < 0.05) in the presence or absence of OT. It is concluded that, in vitro, OT stimulates PGE2 synthesis by the bovine cervix at oestrus and that this effect is mediated by cyclooxygenase.


Assuntos
Bovinos/metabolismo , Colo do Útero/metabolismo , Dinoprostona/metabolismo , Ocitocina/farmacologia , Prostaglandina-Endoperóxido Sintases/biossíntese , Animais , Western Blotting , Bovinos/fisiologia , Colo do Útero/efeitos dos fármacos , Colo do Útero/enzimologia , Estudos de Coortes , Inibidores de Ciclo-Oxigenase/farmacologia , Dinoprosta/metabolismo , Relação Dose-Resposta a Droga , Indução Enzimática/efeitos dos fármacos , Estro/metabolismo , Feminino , Indometacina/farmacologia , Progesterona/farmacologia , Prostaglandina-Endoperóxido Sintases/efeitos dos fármacos
16.
Avian Pathol ; 25(3): 581-90, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18645880

RESUMO

Acetylsalicylic acid (ASA) inhibits the in vitro formation of many cyclooxygenases, some of which in mammals regulate pulmonary vasoconstriction. Pulmonary vasoconstriction occurs in some species subsequent to hypoxaemia, through the mediation of cyclooxygenases. If this effect also is manifested in broilers, ASA might have a therapeutic potential in ameliorating the pulmonary hypertension syndrome (clinically manifested as the ascites syndrome) induced by, amongst other factors, exposure to low ambient temperatures. Male broilers were fed pellets containing 500 parts/10(6) of ASA from 3 weeks of age. After 1 week, ASA-treated and control (no ASA) groups were moved to a cold environment for 4 weeks. The development of the ascites syndrome was monitored by recording haematocrit and mortality with ascites. The plasma levels of two cyclooxygenases, the prostaglandins PGE2 and PGF2alpha, were measured in birds in the cold-exposed groups. No differences in haematocrit values, overall mortality or plasma prostaglandins levels were noted between the ASA-treated and control groups during the period of cold exposure. There was an increased mortality in the ASA-treated groups during weeks 3 to 4 of cold exposure, indicating possible inhibition of a cyclooxygenase vasodilator, which could exacerbate a possible existing pulmonary vasoconstriction. The protocol of this field trial does not indicate that ASA might be of therapeutic use in preventing the ascites syndrome in broilers.

17.
Vet Hum Toxicol ; 38(2): 135-6, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8693688

RESUMO

Dried Tomato vines (DTV) are used as a feedstuff in some beef cattle in Israel, despite the literature citation that tomato vines contain potentially harmful steroid alkaloids. A small-scale feeding trial over 42 d examined possible deleterious effects of feeding DTV, compared with wheat straw, in beef cows. No differences in hematological values, serum parameters for body weight were seen between the 2 groups. Steroid alkaloid content of the DTV was not examined, but toxic levels of nitrates were found. The main practical hazard in feeding DTV would appear to be from their potentially high nitrate content.


Assuntos
Alcaloides/toxicidade , Ração Animal/toxicidade , Biomarcadores/sangue , Solanum lycopersicum/toxicidade , Análise de Variância , Animais , Bovinos , Doenças dos Bovinos/etiologia , Contagem de Eritrócitos/efeitos dos fármacos , Feminino , Hematócrito , Hemoglobinas/efeitos dos fármacos , Hemoglobinas/metabolismo , Israel , Intoxicação por Plantas/veterinária , Progesterona/sangue
18.
Vet Immunol Immunopathol ; 47(1-2): 179-84, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8533296

RESUMO

We have investigated the possible linkage between serum and uterine fluid immunoglobulin G (IgG) levels and the hormonal status of the cow. In cycling cows there was a significant (P < 0.01) drop in average (of 4 consecutive days) serum IgG levels, from 36.4 +/- 6.7 mg ml-1 during the luteal phase of the estrous cycle to 28.3 +/- 5.3 mg ml-1 during and around estrus. In prepartum cows, there was a significant drop (P < 0.01) from an average of 37.6 +/- 3.7 mg ml-1 from 5 consecutive days, i.e. 11-7 before parturition, to 28.0 +/- 5.5 mg ml-1 on the day of parturition. Total IgG in the uterine fluid ranged from 30 to 115 mg in one horn and from 24 mg ml-1 to 70 mg ml-1 in the other horn during the luteal phase, but was essentially undetectable at estrus. The drop in serum and uterine IgG occurred concomitantly with the drop in peripheral serum progesterone, from 2-3 ng ml-1 at the luteal phase, and 11-7 days before calving to less than 0.5 ng ml-1 around estrus and calving. Data suggest a possible linkage between steroid hormone and IgG levels.


Assuntos
Bovinos/fisiologia , Imunoglobulina G/imunologia , Progesterona/sangue , Útero/imunologia , Animais , Líquidos Corporais/imunologia , Bovinos/sangue , Estro/fisiologia , Feminino , Imunodifusão/veterinária , Trabalho de Parto/fisiologia , Gravidez , Radioimunoensaio/veterinária
19.
Psychol Aging ; 10(1): 76-83, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7779319

RESUMO

Given the aging workforce, understanding the retirement process is an area of increasing interest to organizations. T. A. Beehr's (1986) model of retirement behavior was used in this study as a basis for selecting personal, psychological, and organizational predictors of subsequent planned retirement age. In addition, potential differences in predictors of the planned retirement age of retirement-eligible and retirement-ineligible respondents were explored. Two hundred sixty-four respondents working for a large multinational firm completed 2 surveys on their attitudes toward work and retirement. Results showed that chronological age, employee health, and self-perceptions of the ability to adjust to retirement predicted subsequent planned retirement age. Interactions of the predictors with retirement eligibility are reported along with implications for retirement-planning programs.


Assuntos
Envelhecimento/psicologia , Atitude , Aposentadoria/psicologia , Adaptação Psicológica , Adulto , Idoso , Feminino , Humanos , Satisfação no Emprego , Masculino , Pessoa de Meia-Idade , Pensões
20.
Drug Metab Dispos ; 23(1): 119-23, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7720514

RESUMO

The incubation of 1-O-clofibryl glucuronide (1-O-CAG), a metabolite of clofibrate, with glutathione (GSH) resulted in the appearance of a new peak when analyzed by HPLC. The use of HPLC coupled to electrospray-MS permitted the identification of the peak as S-(p-chlorophenoxy-2-methylpropanoyl)glutathione (CA-SG), formed by nucleophilic displacement of the glucuronide moiety from 1-O-CAG. Conjugate formation was enhanced 8-fold by rat liver glutathione S-transferases (GSTs). GSH was unreactive with isomers of 1-O-CAG formed by acyl migration, indicating that 1-O-CAG itself was the preferred substrate. Rearrangement of 1-O-CAG to its isomers in vitro, was found to be decreased in the presence of GSH. In vivo studies indicated that, following an intravenous infusion of clofibric acid to rats (75 mg/kg), the concentration of CA-SG excreted in bile over 4 hr, was approximately 0.1% of the concurrent CAG concentrations. Although these results indicate a minor role for GST-catalyzed reactions in clofibrate metabolism in vivo, they do define 1-O-acyl-linked glucuronides as a new class of substrates for GSTs.


Assuntos
Ácido Clofíbrico/metabolismo , Glutationa/metabolismo , Animais , Bile/química , Bile/metabolismo , Cromatografia Líquida de Alta Pressão , Ácido Clofíbrico/farmacocinética , Cromatografia Gasosa-Espectrometria de Massas , Glutationa Transferase/metabolismo , Hidrólise , Isomerismo , Fígado/enzimologia , Fígado/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
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