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931.
Some individuals may have an inherent reactivity to alcohol that facilitates early development of characteristics associated with alcoholism. Although response to alcohol cues has been used to assess this reactivity, few studies have included women or investigated familial alcoholism as a variable. In this study, 23 female college students were divided into groups according to family history of alcoholism (positive or negative). Alcohol reactivity was measured by salivation, skin temperature, heart rate, mood state, and craving for alcohol following presentation of alcohol-related and neutral cues. Results indicate no correlation between salivary reactivity and alcohol craving, which suggests that these variables tap into different domains of cue reactivity. Findings demonstrate that alcohol cue reactivity can be assessed in female social drinkers and that familial alcoholism may influence salivary reactivity to alcohol-related cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
932.
Matuszewich Leslie; Lorrain Daniel S.; Hull Elaine M. 《Canadian Metallurgical Quarterly》2000,114(4):772
Dopamine (DA) is responsive to hormonal manipulations and has been implicated in the regulation of female rat sexual behavior. In the present studies, extracellular DA levels were assessed in the medial preoptic area (MPOA) of ovariectomized female rats in response to exogenous ovarian hormones and during sexual activity. In female rats primed with a low dose of estradiol benzoate (2 μg), but not with a higher dose (20 μg), a 500-μg progesterone injection increased extracellular DA and facilitated copulatory behavior. Extracellular DA levels in the MPOA were further augmented during sexual interactions with a male rat in a nonpacing copulatory chamber by either perineal or vaginal stimulation. However, in a pacing chamber, DA efflux did not increase, although the metabolites rose significantly during copulation. Together, these findings suggest that extracellular DA in the MPOA responds to the hormonal state of the female rat and may contribute to her expression of sexual behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
933.
The objective of this field study was to identify metabolic tests available in clinical practice that identified cows at increased risk of left displaced abomasum (LDA). A technician visited 1044 cows in 20 herds weekly from 1 wk before expected calving until 1 wk postpartum. Cows were assigned a body condition score and samples were collected at each visit for measurement of serum nonesterified fatty acids (NEFA), cholesterol, beta-hydroxybutyrate (BHBA), glucose, urea, calcium, and phosphorus, and a milk sample was collected postpartum for measurement of BHBA. The probability of LDA was modeled with multivariable logistic regression accounting for clustering. There were 53 cases of LDA (incidence risk = 5.1%) and the median time of diagnosis was 11 d in milk. In cows with LDA, mean NEFA concentrations began to diverge from the mean in cows without LDA 14 d before calving, whereas mean serum BHBA concentrations did not diverge until the day of calving. Prepartum, only NEFA concentration was associated with risk of subsequent LDA. Between 0 and 6 d before calving, cows with NEFA concentration > or =0.5 mEq/L were 3.6 times more likely to develop LDA after calving. For prospective application, among samples taken 4 to 10 d before expected calving, the optimum NEFA cut-point remained 0.5 mEq/L. The sensitivity, specificity, and likelihood ratio (LR) were 46%, 82%, and 2.6, respectively. Between 1 and 7 d postpartum, retained placenta, metritis, and increasing serum concentrations of BHBA and NEFA were associated with increased risk of subsequent LDA. However, considered separately, postpartum serum BHBA was a more sensitive and specific test than NEFA concentration. The odds of LDA were 8 times greater in cows with serum BHBA > or =1200 micromol/L (LR = 3.5). Cows with milk BHBA concentration > or =200 micromol/L were 3.4 times more likely to develop LDA. Serum calcium concentration was not associated with LDA. Strategic use of metabolic tests to monitor transition dairy cows should focus on NEFA in the last week prepartum and BHBA in the first week postpartum. 相似文献
934.
935.
Andy Ruiz Yadira Palacios Irene Garcia Leslie Chavez-Galan 《International journal of molecular sciences》2021,22(11)
Tumor necrosis factor (TNF) is one of the main cytokines regulating a pro-inflammatory environment. It has been related to several cell functions, for instance, phagocytosis, apoptosis, proliferation, mitochondrial dynamic. Moreover, during mycobacterial infections, TNF plays an essential role to maintain granuloma formation. Several effector mechanisms have been implicated according to the interactions of the two active forms, soluble TNF (solTNF) and transmembrane TNF (tmTNF), with their receptors TNFR1 and TNFR2. We review the impact of these interactions in the context of mycobacterial infections. TNF is tightly regulated by binding to receptors, however, during mycobacterial infections, upstream activation signalling pathways may be influenced by key regulatory factors either at the membrane or cytosol level. Detailing the structure and activation pathways used by TNF and its receptors, such as its interaction with solTNF/TNFRs versus tmTNF/TNFRs, may bring a better understanding of the molecular mechanisms involved in activation pathways which can be helpful for the development of new therapies aimed at being more efficient against mycobacterial infections. 相似文献
936.
Laura Castilla-Vallmanya Semra Gürsoy
zlem Giray-Bozkaya Aina Prat-Planas Gemma Bullich Leslie Matalonga Mnica Centeno-Pla Raquel Rabionet Daniel Grinberg Susanna Balcells Roser Urreizti 《International journal of molecular sciences》2021,22(4)
We present a Turkish family with two cousins (OC15 and OC15b) affected with syndromic developmental delay, microcephaly, and trigonocephaly but with some phenotypic traits distinct between them. OC15 showed asymmetrical skeletal defects and syndactyly, while OC15b presented with a more severe microcephaly and semilobal holoprosencephaly. All four progenitors were related and OC15 parents were consanguineous. Whole Exome Sequencing (WES) analysis was performed on patient OC15 as a singleton and on the OC15b trio. Selected variants were validated by Sanger sequencing. We did not identify any shared variant that could be associated with the disease. Instead, each patient presented a de novo heterozygous variant in a different gene. OC15 carried a nonsense mutation (p.Arg95*) in PORCN, which is a gene responsible for Goltz-Gorlin syndrome, while OC15b carried an indel mutation in ZIC2 leading to the substitution of three residues by a proline (p.His404_Ser406delinsPro). Autosomal dominant mutations in ZIC2 have been associated with holoprosencephaly 5. Both variants are absent in the general population and are predicted to be pathogenic. These two de novo heterozygous variants identified in the two patients seem to explain the major phenotypic alterations of each particular case, instead of a homozygous variant that would be expected by the underlying consanguinity. 相似文献
937.
Shasika Jayarathne April J. Stull Oak‐Hee Park Jung Han Kim Leslie Thompson Naima Moustaid‐Moussa 《Molecular nutrition & food research》2019,63(20)
Obesity is a complex disease and a major public health epidemic. Chronic, low‐grade inflammation is a common underlying feature of obesity and associated metabolic diseases; adipose tissue is a major contributor to this systemic inflammation. Evidence shows that obesity‐associated inflammation may originate from gut dysfunction, including changes in intestinal bacteria or microbiome profiles. Increasingly, food and plant bioactive compounds with antioxidant and anti‐inflammatory properties are proposed to ameliorate obesity‐associated inflammation. Among these, the health‐promoting effects of anthocyanin‐rich foods are of interest here. Specifically, this review summarizes the reported benefits of anthocyanins in obesity‐associated inflammation and underlying molecular mechanisms, including the role of gut microbiome and cell signaling pathways regulated by anthocyanins both in vivo and in vitro. 相似文献
938.
John Doelman Leslie L. McKnight Michelle Carson Kelly Nichols Douglas F. Waterman John A. Metcalf 《Journal of dairy science》2019,102(2):1274-1280
Gluconic acid is a carboxylic acid naturally occurring in plants and honey. In nonruminant animals, gluconic acid has been shown to increase gastrointestinal butyrate concentrations and improve growth performance, but a ruminant application remains undescribed. This experiment examined the effects of postruminal calcium gluconate (CaG) on milk production, fecal volatile fatty acid concentrations, and plasma metabolite concentrations in lactating dairy cows. Six rumen cannulated multiparous Holstein cows (60 ± 6 d in milk) were randomly assigned to 6 treatment sequences within a 6 × 6 Latin square design in which each experimental period consisted of 5 d of continuous postruminal infusion followed by a 2 d wash-out period. Test treatments included a negative control (CON; 0.90% NaCl wt/vol), positive control (Na-butyrate, 135 g/d), and 4 doses of CaG (44, 93, 140, and 187 g/d). Cows received a total mixed ration (31% corn silage, 28% alfalfa silage, 5% hay, 36% concentrate) with dry matter intake fixed (25.3 ± 1.7 kg/d) throughout the experiment. On d 5 of each infusion period, samples of milk, feces, and blood were collected from each animal. Calcium gluconate treatments increased milk fat concentration, and a tendency was observed for increased milk fat yield and energy-corrected milk yield above levels achieved by CON, with maximal treatment responses of 4.43% (CON 3.81%), 2.089 kg/d (CON 1.760 kg/d), and 51.8 kg/d (CON 47.1 kg/d), respectively. Concentrations of iso-butyric acid in feces were greater in cows infused with CaG (13.3 µmol/g) treatments compared with CON (9.7 µmol/g). Arterial concentrations of glucose and nonesterified fatty acids were lower (glucose: CaG 2.98 mmol/L, CON 3.29 mmol/L and nonesterified fatty acids: CaG 0.130 mmol/L vs. 0.148 mmol/L) and β-hydroxybutyrate higher (CaG 1.703 vs. CON 0.812) in cows infused with CaG than CON. Together, these results suggest that postruminal infusion of CaG may alter metabolic mechanisms to support a milk fat production response. 相似文献
939.
C.G. Todd S.T. Millman K.E. Leslie N.G. Anderson J.M. Sargeant T.J. DeVries 《Journal of dairy science》2018,101(9):8236-8247
Acidification is a practical way of preserving the bacteriological quality of milk so that it can be fed to calves under free-access conditions. The objectives of this study were to evaluate how milk replacer acidification and free-access feeding affect dairy calf behavior during the first week of life. Sixteen Holstein male calves were purchased at birth and transported to the University of Guelph Kemptville Campus Dairy Education and Research Centre. Calves were randomly assigned to 1 of 4 milk feeding programs: (1) free-access (ad libitum) feeding of acidified milk replacer (22% crude protein and 17% fat, 150 g/L; FA); (2) restricted (6 L/d, 150 g/L) feeding of acidified milk replacer (RA); (3) free-access feeding of nonacidified milk replacer (FN); and (4) restricted feeding of nonacidified milk replacer (RN). Formic acid was used to acidify milk replacer to a target pH between 4.0 and 4.5. Video recordings of each calf at 1, 2, and 6 d were analyzed continuously over 24 h for all occurrences of each behavior in the ethogram. Feeding behavior observations were organized into sucking bouts, from which feeding behavior outcome variables were calculated. Calves consuming acidified milk replacer demonstrated more fragmented feeding patterns, characterized by more pauses within a sucking bout (FA, FN, RA, and RN calves = 12.4, 4.4, 13.7, and 11.9 pauses/bout, respectively) and longer sucking bout duration (FA, FN, RA, and RN calves = 8.8, 5.2, 9.3, and 8.1 min/bout, respectively), than calves fed nonacidified milk replacer. Restricted-fed calves tended to have longer sucking bouts and performed more within-bout sucks (FA, FN, RA, and RN calves = 10.7, 5.8, 13.5, and 14.1, respectively) and pauses than free-access calves. Acidification and free-access feeding did not affect lying duration. Calves assigned to the acidified feeding treatments tended to perform more grooming behavior than those fed nonacidified milk replacer (FA, FN, RA, and RN calves = 0.9, 0.5, 0.8, and 0.6 h/d, respectively). Free-access feeding did not affect grooming duration. The observed differences in feeding and grooming behavior suggest that acidification to a pH between 4.0 and 4.5 may have altered the palatability of milk replacer. Calves assigned to the acidified milk replacer feeding treatments did not, however, show avoidance toward this feedstuff during the first week of life. 相似文献
940.