|Record 1 of 22 in AGRICOLA (1998-2001/09)
AN: IND 22061249
AU: Hagen,-C.D.; Lindemann,-M.D.; Purser,-K.W.
TI: Effect of dietary chromium tripicolinate on productivity of sows under commercial conditions.
SO: Swine-health-prod. Perry, IA : American Association of Swine Practitioners. Mar/Apr 2000. v. 8 (2) p. 59-63.
CN: DNAL SF971.N472
IS: ISSN: 1066-4963
DE: sows-. sow-feeding. chromium-. supplementary-feeding. productivity-. litter-size. reproductive-performance. mortality-. cost-benefit-analysis.
Record 2 of 22 in AGRICOLA (1998-2001/09)
AN: IND 22029001
TI: Chromium as a supplement.
SO: Annu-rev-nutr. Palo Alto, Calif. : Annual Reviews Inc., c1981-. 1999. v. 19 p. 279-302.
CN: DNAL QP141.A1A63
IS: ISSN: 0199-9885
DE: chromium-. mineral-supplements. chemical-speciation. dietary-minerals. nutrient-sources. intestinal-absorption. excretion-. nutritional-state. nutrition-physiology. mode-of-action. stress-. growth-. animal-nutrition. carcass-composition. carcass-quality. immunity-. sexual-reproduction. glucose-tolerance. hyperlipemia-. body-composition. exercise-. weight-losses. toxicity-. iron-. literature-reviews. nutrient-nutrient-interactions.
AB: Chromium (Cr) is an essential mineral element that has received considerable public attention. The suggestion that Cr intake is generally low has generated interest regarding the purported beneficial effects of Cr supplementation on biological function and health of animals and humans. This review briefly describes key aspects of Cr nutritional status and evaluates the effects of Cr supplementation on various components of biological function, body composition, and health. A novel biological role of Cr in regulation of insulin function is described. Although promising results of Cr supplementation are presented, the considerable challenge of developing methods for routine assessment of Cr nutriture in humans remains.
Record 3 of 22 in AGRICOLA (1979 - 1984)
AN: IND 81076967
AU: Anderson,-R.A.; Polansky,-M.M.
TI: Dietary chromium deficiency effect on sperm count and fertility in rats.
SO: Biol-Trace-Elem-Res. Clifton, N.J., Humana Press. Mar 1981. v. 3 (1) p. 1-5.
CN: DNAL QP534.B56
Record 4 of 22 in AGRICOLA (1979 - 1984)
AN: IND 80094955
CA: Poultry Science Society.
TI: Effect of protein source and chromium on turkey reproduction.
SO: Poult-Sci. Champaign, Ill., Poultry Science Association. July 1980. v. 59 (7) p. 1610-1611.
CN: DNAL 47.8-AM33P
IS: ISSN: 0032-5791
Record 5 of 22 in AGRICOLA (1992-1997)
AN: IND 20593405
TI: Supplemental chromium may provide benefits, but costs must be weighed.
SO: Feedstuffs. Carol Stream, Ill. : Miller Publishing Company. Dec 23, 1996. v. 68 (53) p. 14-17.
CN: DNAL 286.81-F322
IS: ISSN: 0014-9624
DE: pig-feeding. chromium-. feed-supplements. costs-. reproductive-performance.
Record 6 of 22 in AGRICOLA (1992-1997)
AN: IND 20549612
AU: Yang,-W.Z.; Mowat,-D.N.; Subiyatno,-A.; Liptrap,-R.M.
TI: Effects of chromium supplementation on early lactation performance of Holstein cows.
SO: Can-j-anim-sci. Ottawa : Agricultural Institute of Canada, 1957. June 1996. v. 76 (2) p. 221-230.
CN: DNAL 41.8-C163
LA: English; Summary in: French
IS: ISSN: 0008-3984
DE: dairy-cows. chromium-. supplementary-feeding. milk-yield. lactation-stage. hydrocortisone-. corticotropin-. lh-. gnrh-. progesterone-. blood-sugar. milk-composition. reproductive-performance. animal-health. 3-hydroxybutyric-acid. blood-serum.
AB: Two experiments were conducted to evaluate the effects of chromium (Cr) supplementation on early lactation performance of Holstein cows. Experiment 1 involved 12 primiparous (PP) and 22 multiparous (MP) cows, while exp. 2 involved 18 PP and 22 MP cows. In each trial, cows were fed total mixed rations (TMR) and assigned to one of two treatments: control or 0.5 mg kg-1 supplemental chelated Cr from week 6 prepartum to week 16 postpartum. The cortisol response to synthetic adrenocorticotropin (ACTH) intramuscular (i.m.) and the luteinizing hormone (LH) response to synthetic gonadotropin-releasing hormone (GnRH) i.m. were evaluated as well, during weeks 2 and 6 postpartum in exp. 2. During the first 16 wk of lactation, supplemental Cr tended to increase milk yields in PP cows by 13% (P = 0.06) and increased milk production by 7% (P < 0.05) in exps. 1 and 2, respectively, but had no effect in MP cows. Despite increased milk yield, Cr supplementation had no adverse effect on milk composition, reproductive performance, or health status. Furthermore, Cr supplementation tended to increase the milk lactose content in PP cows. Supplemental Cr reduced serum beta-hydroxybutyrate levels and may reduce subclinical ketosis in MP cows. In addition, in overconditioned, aged cows, Cr supplementation may reduce the incidence of certain other metabolic disorders. Peak values and production rates of cortisol in Cr-supplemented cows tended to be greater (P < 0.10) than in control cows at week 6 Basal LH concentrations did not differ between the two treatments for either week. However, the Cr-supplemented cows released less (P < 0.05) LH than did control cows at week 6. Results from hormone-stimulation tests suggest that.
the Cr-supplemented cows may have experienced a greater stress with their increased milk production. However, the time in postpartum anestrus and the time to conception were similar, suggesting that Cr supplementation may have mitigated the slower return to fertility usually seen in higher producing PP dairy cows. Further study is needed to determine the effects of Cr supplementation on reproductive performance, health status, and metabolic disorders in dairy cows.
Record 7 of 22 in AGRICOLA (1992-1997)
AN: IND 20499497
TI: Hypothesis provides possible explanation as to chromium's effect on reproductive efficiency in swine.
SO: Feedstuffs. Carol Stream, Ill. : Miller Publishing Company. Dec 25, 1995. v. 67 (53) p. 12, 23.
CN: DNAL 286.81-F322
IS: ISSN: 0014-9624
DE: pig-feeding. chromium-. reproductive-efficiency. feed-supplements. insulin-.
Record 8 of 22 in AGRICOLA (1992-1997)
AN: IND 20450540
AU: Lindemann,-M.D.; Wood,-C.M.; Harper,-A.F.; Kornegay,-E.T.; Anderson,-R.A.
TI: Dietary chromium picolinate additions improve gain:feed and carcass characteristics in growing-finishing pigs and increase litter size in reproducing sows.
SO: J-anim-sci. Champaign, Ill. : American Society of Animal Science. Feb 1995. v. 73 (2) p. 457-465.
CN: DNAL 49-J82
IS: ISSN: 0021-8812
DE: pigs-. sows-. dietary-minerals. chromium-. picolinic-acid. carcass-composition. feed-conversion. sow-reproduction. female-fertility. backfat-. fat-thickness. litter-size. blood-serum. insulin-. blood-sugar. sow-pregnancy.
AB: Growth trials were conducted to determine the effects of Cr as chromium picolinate at various protein levels on performance of growing pigs. The effects of continued supplementation on sow fecundity and body weight changes through two parities also were examined. In Trial 1.48 crossbred pigs (40.9 kg initial weight) were assigned to one of three diets (0, 250, or 500 ppb of added Cr). The only observed difference was an overall trend for an improvement in gain:feed when Cr was added to the diet (P < .10). In Trial 2, 105 crossbred pigs (14.5 kg initial weight) were assigned to one of seven treatments involving a combination of two factors: 1) lysine level at 100 or 120% of NRC (1988) requirement estimate and 2) added Cr level (0, 100, 200, 500, or 1,000 ppb). A Cr X lysine interaction ( P < .02) for gain:feed existed that demonstrated that the addition of 200 ppb of Cr resulted in improved gain: feed at the 100% of requirement lysine level but not at the 120% of requirement lysine level. The addition of 200 ppb Cr also reduced backfat (P < .04) and increased longissimus muscle area (P < .04) regardless of lysine level in the diet. Gilts were retained from Trial 2 to assess the effects of continued Cr supplementation on performance through two parities; gilts fed diets with 0 or 200 ppb of added Cr during the growth trial were continued on those levels and gilts fed diets with 500 or 1,000 ppb of added Cr during the growth trial were fed 0 ppb of added Cr through breeding and reproduction. Sows fed added Cr had larger litters (P < .03) than sows unsupplemented throughout life. Assessment of pre- and postfeeding blood samples in mid-gestation revealed that serum insulin and insulin:glucose.
ratio were affected (P < .003) by Cr supplementation, indicating greater efficiency of insulin action. Chromium from chromium picolinate produces favorable biological responses in swine.
Record 9 of 22 in SilverPlatter MEDLINE(R) (2001/01-2001/10)
TI: Sublethal effects of chromium-VI in the Asian clam (Potamocorbula amurensis).
AU: Teh,-S-J; Werner,-I; Hinton,-D-E
SO: Mar-Environ-Res. 2000 Jul-Dec; 50(1-5): 295-300
AB: Previously, we have shown that Asian clams (Potamocorbula amurensis) with highest metallic body burdens have highest prevalence of disease and lowest reproduction. The present study was designed to assess and validate potential sublethal toxicity of hexavalent chromium (Cr-VI) in clams under controlled laboratory exposure. For 7 days, three replicates of clam (n = 10 per replicate) were exposed to aqueous solution containing 0.00, 0.92, 8.40, or 25.6 mg l-1 of Cr-VI at 15 degrees C and 15 g l-1 salinity. Mortality reached 100% in the 25.6 mg l-1 group within 7 days. There was no significant difference in mortality among the control, 0.92, and 8.40 mg l-1 groups. Western blot analyses revealed significantly elevated stress protein hsp70 levels in the 8.40 mg l-1 treatment group. Histopathologic analyses revealed mild digestive gland (DG) atrophy in the control group. Clams exposed to 0.92 mg l-1 Cr-VI showed moderate DG atrophy, moderate granulomatous inflammation and necrosis in DG, ovary and testis. Lesions observed in the 8.40 mg l-1 treatment group included severe DG atrophy, severe granulomatous inflammation and necrosis in byssal gland, DG, gill, kidney, ovary and testis. In gills and testes of treated groups, apoptotic cells outnumbered mitotic cells. In addition, gills from clams in the 8.40 mg l-1 group showed enhanced hsp70 staining. Our studies support a cause-effect relationship between contaminants and reduced health in Asian clams and indicate the DGs, gills, and reproductive organs are principal targets of Cr-VI toxicity at sublethal concentrations. Results from this study suggest that Cr-VI may have played a role in the increased incidence of diseased clams seen in previous studies and these adverse effects may be working to decrease clam populations at sites with highest metallic contamination in the San Francisco Bay Estuary.
CN: CA45131CANCI; ES04699ESNIEHS
Record 10 of 22 in SilverPlatter MEDLINE(R) (2001/01-2001/10)
TI: Long-term effects on male reproduction of early exposure to common chemical contaminants in drinking water.
AU: Veeramachaneni,-D-N; Palmer,-J-S; Amann,-R-P
SO: Hum-Reprod. 2001 May; 16(5): 979-87
AB: We evaluated sequelae to early exposure of male rabbits to drinking water containing chemicals typical of ground water near hazardous waste sites. The mixture (p.p.m. at 1x) was 7.75 arsenic, 1.75 chromium, 9.25 lead, 12.5 benzene, 3.75 chloroform, 8.5 phenol and 9.5 trichloroethylene. Dutch-Belted does received mixture at 0x (deionized water; control), 1x or 3x as drinking water from day 20 pregnancy through weaning. Exposure of individual males (7-9/treatment) continued until 15 weeks (adolescence); then, all males received deionized water. At 57-61 weeks of age, ejaculatory capability and seminal, testicular, epididymal and endocrine characteristics were evaluated. At 10 opportunities with a female teaser, all seven control males ejaculated every time, but 12 of the 17 treated males failed to express interest, achieve erection and/or ejaculate on one to five occasions; four of the 12 accomplished ejaculation with a second male teaser. Total spermatozoa/ejaculate and daily sperm production were unaffected. However, treatment caused (P < 0.03) acrosomal dysgenesis and nuclear malformations. Baseline serum concentrations of LH were lower, but with borderline significance (P = 0.05). Testosterone secretion after exogenous human chorionic gonadotrophin (P < 0.04) was low. Thus, even at 45 weeks after last exposure to drinking water pollutants, mating desire/ability, sperm quality, and Leydig cell function were subnormal.
Record 11 of 22 in SilverPlatter MEDLINE(R) (2001/01-2001/10)
TI: Inductively coupled plasma emission spectroscopic and flame photometric analysis of goat epididymal fluid.
AU: Gaur,-M; Pruthi,-V; Prasad,-R; Pereira,-B-M
SO: Asian-J-Androl. 2000 Dec; 2(4): 288-92
AB: AIM: The elemental composition of the epididymal luminal fluid (ELF) in adult goat (Capra indica) was investigated. METHODS: ELF was collected by micropuncture from twelve sites along the epididymal duct. The elemental contents was analyzed with inductively coupled plasma (ICP) emission spectroscopy, a microanalytical technique that can simultaneously measure many elements in minute volumes of sample. The Na and K concentrations were determined by flame photometry. RESULTS: ICP spectroscopy showed the presence of copper, calcium, nickel, iron, magnesium, chromium, titanium and zinc in ELF, with fluctuating levels at different sites along the length of the epididymis. Cadmium, cobalt, lead and manganese were not found. The Na+/K+ ratio was seen to be higher at the initial segments of the epididymis and lower at the distal. CONCLUSION: It is proposed that the observed characteristic distribution of elements in ELF may have far reaching implications in sperm maturation and storage known to occur in the epididymis.
Record 12 of 22 in MEDLINE(R)+ (1998-2000)
TI: Preconception urethane or chromium(III) treatment of male mice: multiple neoplastic and non-neoplastic changes in offspring.
AU: Yu,-W; Sipowicz,-M-A; Haines,-D-C; Birely,-L; Diwan,-B-A; Riggs,-C-W; Kasprzak,-K-S; Anderson,-L-M
SO: Toxicol-Appl-Pharmacol. 1999 Jul 15; 158(2): 161-76
AB: Increase in neoplasia in offspring after preconception exposure of parents presents puzzling features such as high frequency of effects and lack of Mendelian inheritance. The present study examined the hypothesis that preconception carcinogenesis involves an increase in the rate of occurrence of neoplasms with a spontaneous incidence. Male NIH Swiss mice (12 per group) were exposed 2 weeks before mating (once, ip) to urethane (1.5 g/kg) or chromium(III) chloride (1 mmol/kg). Offspring (48-78/sex/group) were examined for all grossly apparent changes when moribund or at natural death, followed by histopathological diagnosis and statistical analysis. Significant exposure-related changes occurred in multiple organs. Ten to 20 percent of offspring showed changes related to paternal exposure, including at least one sired by most treated males. Pheochromocytomas occurred in both male and female offspring after both treatments, with none in controls. These neoplasms are rare in mice and suggest endocrine dysfunction as a component of preconception carcinogenesis. This was supported by increases in thyroid follicular cell and Harderian gland tumors, ovarian cysts, and uterine abnormalities. Lung tumors were increased in female offspring only. Effects seen in offspring only after paternal urethane exposure were an increase in preneoplasia/neoplasia in the glandular stomach (males) and in females, increased lymphoma but decreased incidence of histiocytic sarcoma. Increases in incidence of male reproductive gland tumors and of renal non-neoplastic lesions occurred only after chromium exposure. Thus, preconception exposure of fathers to toxicants had a significant impact on both neoplastic and non-neoplastic changes in almost all tissues in which these lesions often occur naturally during the aging process. Copyright 1999 Academic Press.
Record 13 of 22 in MEDLINE(R)+ (1998-2000)
TI: Thirteen-week subchronic rat inhalation toxicity study with a recovery phase of trivalent chromium compounds, chromic oxide, and basic chromium sulfate.
AU: Derelanko,-M-J; Rinehart,-W-E; Hilaski,-R-J; Thompson,-R-B; Loser,-E
SO: Toxicol-Sci. 1999 Dec; 52(2): 278-88
AB: The toxicity of trivalent chromium compounds; chromic oxide and basic chromium sulfate, was investigated in rats in a 13-week nose-only inhalation study that included a 13-week recovery period. Nose-only exposures to insoluble chromic oxide dust at 4.4, 15, or 44 mg/m3 or soluble basic chromium sulfate dust at 17, 54, or 168 mg/m3 (trivalent chromium equivalent concentrations of 3, 10, and 30 mg/m3) were carried out for 6 h/day, 5 days/week. No compound-related mortality occurred. General toxic effects, only observed with high-exposure levels of basic chromium sulfate, included sporadic signs of labored breathing and depressed body weights. No apparent compound-related effects were noted for sperm motility or morphology, for any concentration of either test material. Bronchoalveolar lavage fluid evaluations showed test material in mononuclear cells with chromic oxide and increased neutrophils, protein, lactic dehydrogenase and cellular debris with basic chromium sulfate. The principle effects for both materials were primarily to the respiratory tract. Chromic oxide caused pathological changes in the bronchial and mediastinal lymphatic tissue and lungs, consisting of the presence of pigment-laden macrophages, lymphoid and septal hyperplasia, and interstitial inflammation similar to that observed with other inert dusts. Basic chromium sulfate produced more severe and widespread effects in the nasal cavity, larynx, lungs, and mediastinal lymph node. Effects were characterized by accumulation of foreign material, infiltration of alveolar macrophages, septal cell hyperplasia, and granulomatous and chronic inflammation. Pigment was still present in chromic oxide and, to a lesser extent, in basic chromium sulfate-treated animals after the 13-week recovery period, with partial recovery of the pathological lesions. A NOAEL was not established for either test material, but 4.4 mg/m3 was thought to be near the NOAEL level for subchronic exposure to chromic oxide. The results of this study indicate significant differences in toxicity to the respiratory tract between trivalent chromium compounds chromic oxide and basic chromium sulfate. These are likely related to differences in acidity and water solubility, rather than chromium concentration per se. This conclusion is substantiated by the lack of effect on other internal organs.
Record 14 of 22 in MEDLINE(R)+ (1998-2000)
TI: Sexual maturation and fertility of male and female mice exposed prenatally and postnatally to trivalent and hexavalent chromium compounds.
AU: Al-Hamood,-M-H; Elbetieha,-A; Bataineh,-H
SO: Reprod-Fertil-Dev. 1998; 10(2): 179-83
AB: The reproductive toxicity of trivalent and hexavalent chromium compounds was investigated in male and female mice exposed to 1000 ppm chromium chloride and potassium dichromate via their mother during gestational and lactational periods. Fertility was reduced in male offspring exposed to either trivalent or hexavalent chromium compounds. Body weights and weights of testes, seminal vesicles and preputial glands were reduced in trivalent-exposed male offspring. The exposure of female mice offspring to trivalent and hexavalent chromium compounds delayed sexual maturation. Fertility was reduced in female offspring exposed to either trivalent or hexavalent chromium compounds. The exposure of female mice to hexavalent chromium compound reduced the number of implantations and viable fetuses respectively. Body weight and weights of ovaries and uteri were reduced in trivalent-exposed female offspring. The results indicate that under our experimental conditions, the exposure of male and female mice offspring to either trivalent or hexavalent chromium compounds during gestational and lactational periods impair reproductive functions and fertility in adulthood.
Record 15 of 22 in MEDLINE(R)+ (1995-1997)
TI: Spermatogenic and steroidogenic impairment after chromium treatment in rats.
SO: Indian-J-Exp-Biol. 1995 Jul; 33(7): 480-4
AB: Feeding of hexavalent chromium at doses of 20, 40 and 60 mg/kg daily for 90 days caused cellular impairment in rat testis. Spermatogenic inhibition coupled with deminution in testicular protein, DNA and RNA was significant at the doses 40 and 60 mg kg chromium. Decline of Leydig cell population and nuclear diameter indicated the steroidogenic impairment and the effect was confirmed by the significant inhibition of 3 beta-delta 5-hydroxy steroid dehydrogenase along with low level of serum testosterone.
Record 16 of 22 in MEDLINE(R)+ (1993-1994)
TI: Differential binding of chromium(VI) and chromium(III) complexes to salmon sperm nuclei and nuclear DNA and isolated calf thymus DNA.
AU: Hneihen,-A-S; Standeven,-A-M; Wetterhahn,-K-E
SO: Carcinogenesis. 1993 Sep; 14(9): 1795-803
AB: The binding of CrCl3.6H2O, Cr(NO3)3.9H2O, [Cr(L-His)2] (NO3)3.H2O, [Cr(L-Cys)(L-His)].3.5H2O, [Cr(L-His)(D-Pen)].H2O, Na[Cr(L-Cys)2].2H2O, K2[Cr(GS)2].3H2O, Na2-CrO4.4H2O, and Na2Cr2O7.2H2O to salmon sperm nuclei and nuclear DNA was determined. The Cr(III)-amino acid complexes and Cr(VI) exhibited significantly lower Cr-nuclei and Cr-DNA binding levels relative to the inorganic complexes CrCl3.6H2O and Cr(NO3)3.9H2O. The binding of CrCl3.6H2O, Cr(NO3)3.9H2O and Na2Cr2O7.2H2O to salmon sperm nuclei and nuclear DNA in the presence of rat lung cytosol was determined under the same conditions. For those complexes studied in both buffer and cytosol, the Cr-DNA binding levels for Cr(III) complexes were higher in buffer than in cytosol, while a relatively higher binding level was observed for Cr(VI) in cytosol than in buffer. Slightly lower nuclear protein levels were present in Cr(VI) incubations than in Cr(III) incubations with nuclei both in the presence and the absence of cytosol. The relative binding of CrCl3.6H2O, Cr(NO3)3.9H2O, [Cr(L-His)2](NO)3.H2O, [Cr(L-Cys) (L-His)].3.5H2O, [Cr(L-His)(D-Pen)].H2O, Na[Cr(L-Cys)2].2H2O and Na2CrO4.4H2O to isolated calf thymus DNA in buffer was also determined. Positively charged, labile inorganic Cr(III) complexes, CrCl3.6H2O and Cr(NO3)3.9H2O, exhibited higher binding to DNA than [Cr(L-His) (D-Pen)].H2O, and no binding to DNA was observed with Cr(VI) and the other neutral, positively and negatively charged, inert Cr(III)-amino acid complexes. Although labile aquo chromium(III) complexes are quite reactive with DNA, the reactivity of chromium(III), formed upon intracellular reduction of carcinogenic chromium(VI), toward DNA will be diminished by complexation with cellular proteins, peptides and amino acids.
Record 17 of 22 in MEDLINE(R)+ (1990-1992)
TI: Measurement of human sperm intracellular water volume by electron spin resonance.
AU: Kleinhans,-F-W; Travis,-V-S; Du,-J; Villines,-P-M; Colvin,-K-E; Critser,-J-K
SO: J-Androl. 1992 Nov-Dec; 13(6): 498-506
AB: An electron spin resonance technique using the spin label tempone and the broadening agent potassium chromium oxalate was used to measure the water volume of human sperm. The toxicity of tempone (5 mmol/L) and potassium chromium oxalate (50 mmol/L) to sperm was measured over a time span of 120 minutes using computer-assisted semen analysis. Tempone had no effect on any computer-assisted semen analysis parameters, including motility. Potassium chromium oxalate reduced sperm motility by an average of 24% during the first 30 minutes of exposure. After selection by swim-up and correction for the presence of dead cells and cytoplasmic droplets, a water volume of 20.0 +/- 2.9 microns3 was obtained. This yields a total volume of 33.9 microns3 if a water compartment of 59% by volume is assumed. These results are consistent with other shape-independent techniques for measuring volume, but larger than the generally accepted optical and electronic particle counter sizes.
Record 18 of 22 in MEDLINE(R)+ (1990-1992)
TI: Ascorbate is the principal reductant of chromium(VI) in rat lung ultrafiltrates and cytosols, and mediates chromium-DNA binding in vitro.
AU: Standeven,-A-M; Wetterhahn,-K-E
SO: Carcinogenesis. 1992 Aug; 13(8): 1319-24
AB: Chromium(VI) reductase activity was measured in ultrafiltrates of rat lung after various pretreatments in vitro at 37 degrees C and pH 7.0. Pretreatment of ultrafiltrates with L-ascorbate oxidase (EC 188.8.131.52), which specifically eliminated ascorbate, blocked approximately 95% of chromium(VI) reductase activity in ultrafiltrates. Preincubation of ultrafiltrates with heat-denatured ascorbate oxidase or the sulfhydryl-blocking agent N-ethylmaleimide (NEM) had no significant effect on Cr(VI) reductase activity. In rat lung cytosols, L-ascorbate oxidase blocked approximately 95% and NEM blocked approximately 15% of Cr(VI) reductase activity. The extent of inhibition of Cr(VI) reductase activity in cytosols by L-ascorbate oxidase was significantly decreased to approximately 75% after addition of 1.0 mM NADPH. When Cr(VI) was incubated with salmon sperm nuclei suspended in rat lung cytosol for 15 min, Cr became bound to nuclear DNA. This Cr-DNA binding was completely inhibited by preincubation of rat lung cytosols with L-ascorbate oxidase and inhibited approximately 60% by preincubation with NEM. Taken together these data suggest that ascorbate and/or ascorbate-dependent factors are the principal reductants of Cr(VI) in both ultrafiltrates and cytosols prepared from rat lung and ascorbate-dependent metabolism of Cr(VI) results in Cr binding to nuclear DNA in vitro. Although sulfhydryl-containing factors and NADPH-dependent factors only make a minor contribution to Cr(VI) reduction in rat lung cytosols, sulfhydryls may be significantly involved in the binding of Cr to nuclear DNA.
Record 19 of 22 in MEDLINE(R)+ (1987-1989)
TI: Uterine clearance mechanisms during the early postovulatory period in mares.
AU: LeBlanc,-M-M; Asbury,-A-C; Lyle,-S-K
SO: Am-J-Vet-Res. 1989 Jun; 50(6): 864-7
AB: Uterine response to inoculation with Streptococcus zooepidemicus organisms, 51Cr-labeled 15-microns microspheres, and charcoal was evaluated in 9 mares (4 resistant and 5 susceptible to endometritis) to determine mechanical and cellular clearance rates during the early postovulatory period. Mares were inoculated at estrus prior to ovulation during estrous cycles 1, 3, and 5. Uterine swab specimens for aerobic and anaerobic bacteriologic culture and serum for progesterone determination were obtained on postovulation day 3 during estrous cycle 1, on the day of ovulation during estrous cycle 3, and on postovulation day 5 during estrous cycle 5. Immediately thereafter, the uterus was irrigated with 50 ml of sterile physiologic saline solution containing tracer amounts of 125I-labeled human serum albumin. Streptococcus zooepidemicus was isolated from 10 of 15 (67%) uterine specimens collected from susceptible mares and incubated aerobically. Escherichia coli also was isolated from 2 of the 10 specimens incubated aerobically. Anaerobic bacteriologic culture of specimens from all mares yielded no growth. Chromium-labeled microspheres were recovered twice from 2 susceptible mares, on day 0 and day 5. Charcoal was retained in 5 specimens collected from 3 susceptible mares. Bacteriologic culture of specimens from resistant mares did not yield growth. On day 0, chromium-labeled microspheres and charcoal were recovered once from 1 resistant mare. Mares susceptible to endometritis accumulated more fluid within the uterine lumen after ovulation than did resistant mares (mean +/- SEM, 52.73 +/- 15.22 ml and 7.41 +/- 1.96 ml, respectively; P less than 0.01). From this study, it appeared that uterine cellular and bactericidal mechanisms are dysfunctional during the early postovulatory period. However, there appeared to be no disruption of the mechanisms responsible for mechanical clearance of materials inoculated in the uterus.
Record 20 of 22 in MEDLINE(R)+ (1981-1986)
TI: Accumulation of toxic metals in male reproduction organs.
AU: Danielsson,-B-R; Dencker,-L; Lindgren,-A; Tjalve,-H
SO: Arch-Toxicol-Suppl. 1984; 7177-80
AB: Occupation exposure to metals has been related to impaired reproduction in males. This report summarizes autoradiographic studies on the distribution of cadmium (Cd), chromium (Cr) and arsenic (As) in the testis and epididymis of rodents. Cd and Cr strongly accumulated in the interstitial tissues, indicating an effect on hormone production (Leydig cells) and blood supply or both. Arsenic accumulated in the lumen of the duct of epididymis causing long-term exposure of the semen.
Record 21 of 22 in MEDLINE(R)+ (1975-1980)
TI: Comparative toxicity of trivalent and hexavalent chromium to rabbits. III. Biochemical and histological changes in testicular tissue.
AU: Behari,-J; Chandra,-S-V; Tandon,-S-K
SO: Acta-Biol-Med-Ger. 1978; 37(3): 463-8
AB: The administration of trivalent and hexavalent chromium compounds produced inhibition of the activity of succinic dehydrogenase, adenosine triphosphatase and acid phosphattase accompanied by cellular degeneration with complete absence of spermatocytes in the testis of rabbits. The biochemical and histological changes were more marked in the animals treated with the trivalent chromium than those exposed to hexavalent chromium and were progressive with the duration of exposure.
Record 22 of 22 in MEDLINE(R)+ (1975-1980)
TI: Studies of nutritional safety of some heavy metals in mice.
AU: Hutcheson,-D-P; Gray,-D-H; Venugopal,-B; Luckey,-T-D
SO: J-Nutr. 1975 Jun; 105(6): 670-5
AB: Heavy metals have been proposed as nutrient markers to allow the accurate determination of the time of passage, nutrient intake, or apparent utilization of multiple nutrients. In order to evaluate possible toxic effects of scandium, chromium, lanthanum, samarium, europium, dysprosium, terbium, thulium, and ytterbium oxides, and barium sulfate upon growth, general development, reproduction, and lactation, mice were fed different levels of these compounds for three generations. The amount of elements fed were 0,110, 100, and 1000 times the use amount. The use amounts were (in ppm2.) : Sc, 0.12; Cr, 0.02; La.0.40;; Sm. 0.80; Eu, 0.036:TB, 1.20; Dy, 1.20; Tm. 0.08; Tb, 0.12; and Ba, 0.008. The use amount was one-fifth of the concentration required for activation analysis. Mortality and morbidity were negligible. No consistent growth rate changes were observed; however, different groups showed different growth rates during different generations. The number of mice born showed no significant differences amoung treatment groups. Survival, growth rate, hematology, morphological development, maturation, reproduction, and lactational performance were comparable in mice fed the different levels of 10 heavy metal oxides to those mice fed the basal diet.