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Sex Dependent (sex + dependent)
Selected AbstractsVariation of metallothionein and metal concentrations in the digestive gland of the clam Ruditapes decussatus: Sex and seasonal effectsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2001Maria A. Serafim Abstract Metallothionein (MT) and metal (Cd, Cu, and Zn) concentrations were determined in the digestive gland of male and female Ruditapes decussatus. Clams were collected monthly during the period of sexual development, from June to September, at two different sites of a coastal lagoon, the Ria Formosa Lagoon, on the south coast of Portugal. The MT concentrations were determined in the heat-treated cytosolic fraction of the digestive gland of both male and female clams. Total metal (Cd, Cu, and Zn) concentrations in the heat-treated cytosol of the digestive gland were also determined in both sexes. The MT and metal concentrations in the digestive gland were not sex dependent in this species. Therefore, these results suggest that random samples can be used to determine MT and metal concentrations in the digestive gland of R. decussatus. Seasonal and site-specific dependency, however, were detected for MT, Cd, and Cu concentrations. The maximum concentration levels of MT, Cd, and Cu were detected in July and August for both sexes in the same area. Zinc concentrations, however, did not show marked seasonal variations, indicating that this species is able to regulate zinc concentrations. The highest MT concentrations were significantly related to the highest metal concentrations. [source] Sex differences in coupled knee motions during the transition from non-weight bearing to weight bearingJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2009Sandra J. Shultz Abstract Knee ligament injuries frequently happen when the joint transitions from non-weight bearing (NWB) to weight bearing (WB). To gain insight into the mechanism that produces these injuries, physically active females (N,=,41) and males (N,=,39) underwent measurement of coupled tibiofemoral joint displacements [anterior tibial translation (ATT) and varus,valgus and internal,external rotations] and neuromuscular responses as the knee transitioned from NWB to WB in response to a 40% body weight load applied under the control of gravity. The transition from NWB to WB produced no difference in ATT between males and females; however, significant sex-based differences were noted for both transverse and frontal plane knee motions. With the knee NWB, females were in a greater absolute valgus compared to males (6.6 vs. 5.0°), and moved through greater varus motion than males during the transition from NW to WB (2.3 vs. 1.4°), resulting in similar valgus alignment for both sexes at peak WB (4.3 vs. 3.6°). In the transverse plane, the knees of females were positioned in more external rotation compared to males when NWB (1.4 vs. ,0.3°), then females externally rotated their knees while males internally rotated their knees during the transition from NWB to WB. This resulted in a 3.4° difference in transverse plane knee position at peak WB (2.3 vs. ,1.1°). Our findings suggest that the coupled knee motions produced during the transition from NWB to WB are sex dependent, and may provide insight into the knee motion patterns that place females at increased risk of knee ligament injury. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 717,723, 2009 [source] Growth, Maturation, Induced Spawning, and Production of the First Generation of South American Catfish, Pseudoplatystoma sp., in North AmericaJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2008Konrad Dabrowski Growth, plasma steroids, and the appearance of gonads (histology and gonadosomatic index) were followed in South American catfish (surubim, Pseudoplatystoma sp.) raised in captivity in the aquaculture facility at The Ohio State University, Columbus, Ohio, USA, from 2003 until 2006. Broodstock growth showed a great individual variation and it did not seem sex dependent. The levels of 11-ketotestosterone were high in males during the reproductive season. Three out of six females spawned after receiving two doses of carp pituitary extract (0.5 and 5 mg/kg) at 11-h intervals. Fertilization was performed in only one female in February 2006. Egg size was 0.73 ± 0.06 mm in diameter at stripping. Two males released sperm, and it was used for fertilization. Sperm concentrations were 24 × 109 and 15.5 × 109 spermatozoa/mL in Male 1 and Male 2, respectively, and viability was confirmed after activation in 0.3% NaCl. Embryo survival at 9 h after fertilization was 44 and 23% for Male 1 and Male 2, respectively. Embryos hatched 15 h after fertilization. Larvae were 3.53 ± 0.09 mm in length at hatching and were successfully raised (72% survival after 2 wks) using live brine shrimp nauplii. [source] The effects of dietary flaxseed on the Fischer 344 rat.CELL BIOCHEMISTRY AND FUNCTION, Issue 6 2005Abstract The hepatotoxic effect of carbon tetrachloride (CCl4) administered by gavage at 0.25,ml CCl4 (1:1 in olive oil) per 100,g body weight was examined 24,h later in regular chow fed (RC) and 10% flax chow fed (FC) male and female Fischer 344 rats. CCl4 -treated RC rats were subdued, lethargic and unkempt. CCl4 -treated FC rats were much less affected. CCl4 treatment resulted in loss of weight in RC and FC rats. In males, the weight loss was 6.7% body mass in RC rats compared to 5.6% body mass in FC rats. In females, the weight loss was 7.5% body mass in both RC and FC rats. While CCl4 treatment increased the level of the liver injury marker plasma alanine aminotransferase (ALT) in RC rats, this CCl4 effect was significantly attenuated in FC rats. In male rats, the ALT increase was 435-fold in RC rats and 119-fold in FC rats, over that of their respective controls. In female rats, the ALT increase was 454-fold in RC rats and 381-fold in FC rats, over that of their respective controls. These results provide evidence that flax consumption protects the liver against injury and that the extent of the protection is sex dependent. CCl4 had no effect on the plasma level of ,-glutamyltranspeptidase (,GT) in RC and FC rats supporting the contention that plasma ,GT is not a useful marker for acute liver injury which is seen in this model. The activity of ,GT was increased in the livers of FC rats compared to RC rats: 2.7-fold in males and 1.5-fold in females. In RC rats, the activity of liver ,GT was decreased by CCl4 treatment: 70% in the male and 25% in the female. However, this CCl4 effect was reversed or abolished by flax consumption. Compared to RC rats: in male FC rats, CCl4 actually increased the activity of liver ,GT 1.28-fold; while in female FC rats, the depressing effect of CCl4 treatment was abolished. The flax-induced preservation of ,GT in the liver in response to injury may be involved in the observed hepatoprotection through generation of GSH. In RC male rats, CCl4 treatment effected a 25% reduction in plasma glucose levels. There was no decrease in CCl4 -treated FC male rats. In female rats, CCl4 treatment effected a 21% decrease in plasma glucose levels in both RC and FC rats. In conclusion, multiple parameters for acute CCl4 -induced injury were attenuated in the FC compared to the RC rat. That flaxseed consumption conferred greater protection against liver injury in the male than in the female suggests an involvement of the estrogenic lignan component of flaxseed. We discuss the possibility that this hepatoprotection is through a flax lignan-induced increase in reduced glutathione related to a flax effect on the activity of liver ,GT in the resting state and the maintenance of its activity in response to injury. Copyright © 2005 John Wiley & Sons, Ltd. [source] | ||||||||||