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1.
Lead and chromium are ubiquitous environmental pollutants and their effects on reproductive physiology as shown by animal experiments and human studies is well documented. The present study was conducted to ascertain the role of these metals on gamete physiology during the sperm-zona binding process, Superovulated ova and capacitated sperm from BALB/c mice were exposed to lead (0.0, 0.2, 0. 5, 1.0 and 2.0 μg/ml) or chromium (0.0, 5.0, 10.0 and 20.0 μg/ml) for 2 h in the culture medium. The sperm that became attached to the ova in the presence of these metals were scored. Synthesis of DNA, RNA and protein was assessed during this process by labelling the cells with [3H]thymidine (20 μCi/ml), [3H]uridine (50 μCi/ml) and [35S]methionine (10 μCi/ml) in the culture medium after exposure to the metals for 2 h. Our studies show a significant dose-dependent decrease in the number of sperm attaching to the ova in both exposed groups along with a decrease in the incorporation of radiolabelled thymidine, uridine and methionine. The results indicate that DNA, RNA and protein synthesis under sperm-zona binding conditions are affected by the presence of these two metals. The physiology of the gametes is altered resulting in a low frequency of sperm attachment to the ova, which in turn leads to a risk of reproductive failure. 相似文献
2.
Kawai Y Takeiri A Suzuki T Suzuki Y Miyake M 《Biological & pharmaceutical bulletin》2000,23(8):922-925
An anti mouse sperm monoclonal antibody (A-1) inhibited sperm penetration into the egg zona pellucida and bound to an acrosomal area of sperm. In this study, we examined whether or not the antibody affects the sperm capacitation and the acrosome reaction. Sperm were incubated in modified Krebs-Ringer bicarbonate medium in the presence or absence of the antibody. The capacitation of sperm was assessed by chlortetracycline fluorescence pattern assay. The percentage of capacitated sperm did not increase in the presence of antibody, but increased time-dependently in its absence. The acrosome reaction of the capacitated sperm was induced by the addition of ionophore. The ionophore, however, failed to induce the reaction in the presence of the A-1 antibody. Next, the calcium influx into spermatocytes was examined. The capacitated sperm, preloaded with Fura-2, were treated with ionomycin in the presence or absence of the A-1 antibody. The influx of calcium ions into capacitated spermatozoa was also inhibited by the antibody. Thus a monoclonal antibody, A-1, inhibited the sperm capacitation, acrosome reaction and calcium influx into spermatocytes. 相似文献
3.
Mercury is one of the most investigated natural elements and potential contaminants in the environment. Antioxidants have long been known to reduce the free radical-induced oxidative damage. Considering the antioxidant properties of melatonin, this study was aimed to evaluate the effect of melatonin on antioxidant system of rat epididymal sperm in vitro. Sperm samples were dispersed in RPS medium (pH 6.9) and incubated with mercury in the form of mercuric chloride (MC) at three different concentrations (1 μM, 10 μM, 100 μM), melatonin (MLT) at a concentration (100 μM) and mercuric chloride+melatonin (100 μM each) for 3 h at 32 °C. Sperm viability and motility were assessed every 30 min during the 3-h incubation period. An aliquot of sperm sample was homogenised, centrifuged and used for the assay of superoxide dismutase, glutathione peroxidase, glutathione reductase, TBARS assay to detect lipid peroxidation and hydrogen peroxide generation assay. Samples treated with mercury showed a dose-dependent decrease in motility while there was no significant decrease in sperm viability. In mercury-incubated sperm, the activity of superoxide dismutase, glutathione peroxidase and glutathione reductase decreased significantly while TBARS levels and H2O2 generation were increased in a dose-dependent manner. Co-incubation of sperm with mercury and melatonin exhibited no significant changes in the levels of motility, viability and antioxidant indices as compared to untreated controls. The results suggest that graded doses of mercury elicit depletion of antioxidant defense system in sperm without altering the viability and melatonin treatment was found to significantly inhibit oxidative damage caused by mercury. 相似文献
4.
Jian-ming HOU En-yu CHEN Shi-chao WEI Fan LIN Qing-ming LIN Xu-hua LAN Ying XUE Man WU 《Acta pharmacologica Sinica》2014,35(4):523-530
Aim: Excessive apoptosis of osteoblasts is the major cause of low bone mass, and bovine lactoferrin (bLF), an iron-binding glycoprotein, might protect osteoblastic cells from apoptosis induced by serum withdrawal. The aim of this study was to elucidate the mechanisms underlying the anti-apoptotic action of bLF in rat osteoblasts in vitro. Methods: Primary rat osteoblasts were incubated in the presence of varying concentrations of bLF for 24 h. The expression of insulin-like growth factor I (IGF-I) and IGF-I receptor (IGF-IR) was measured uisng RT-PCR and Western blotting. Cell apoptosis was examined with flow cytometry. siRNAs targeting IGF-I was used in this study.
Results: Treatment of bLF (0.1–1000 μg/mL) dose-dependently increased the expression of IGF-I and IGF-IR in the osteoblasts. Treatment with bLF (10, 100 μg/mL) markedly inhibited the osteoblast apoptosis (with the rate of total apoptosis of 70% at 10 μg/mL), but the high concentration of bLF (1000 μg/mL) significantly promoted the osteoblast apoptosis. Knockdown of the IGF-I gene in osteoblasts with siRNA markedly increased the osteoblast apoptosis.
Conclusion: Lactoferrin (10 and 100 μg/mL) effectively inhibits apoptosis of primary rat osteoblasts by upregulating IGF-I expression. 相似文献
Results: Treatment of bLF (0.1–1000 μg/mL) dose-dependently increased the expression of IGF-I and IGF-IR in the osteoblasts. Treatment with bLF (10, 100 μg/mL) markedly inhibited the osteoblast apoptosis (with the rate of total apoptosis of 70% at 10 μg/mL), but the high concentration of bLF (1000 μg/mL) significantly promoted the osteoblast apoptosis. Knockdown of the IGF-I gene in osteoblasts with siRNA markedly increased the osteoblast apoptosis.
Conclusion: Lactoferrin (10 and 100 μg/mL) effectively inhibits apoptosis of primary rat osteoblasts by upregulating IGF-I expression. 相似文献
5.
Ping-Chi Hsu Chao-Chin Hsu Ming-Yie Liu Lih-Yuh Chen Yueliang Leon Guo 《Journal of toxicology and environmental health. Part A》2013,76(1):45-64
The relationships between sperm reactive oxygen species (ROS) generation, the capacitation process and acrosome reaction, and the sperm-oocyte penetration rate (SOPR) were investigated to understand the effect of lead toxicity on sperm functions and the mechanisms of these effects. Male Sprague-Dawley rats received weekly intraperitoneal injections of 20 mg or 50 mg lead acetate/kg or 20 mg or 50 mg sodium acetate/kg (control) for 6 wk. Serum testosterone was measured by radioimmunoassay. In cauda epididymal spermatozoa, the chemiluminescence was measured to evaluate the sperm ROS generation. Chlortetracycline fluorescence assay was used to study the status of capacitation and acrosome reaction on fresh cauda epididymal spermatozoa and after 2, 4, or 24 h of incubation with 5 mg/ml bovine serum albumin. In lead-exposed rats, the serum testosterone levels were reduced, and the percentage of capacitation and the chemiluminescence were significantly increased in fresh cauda epididymal spermatozoa. The serum testosterone levels were negatively associated with the percentage of acrosome-reacted spermatozoa. Sperm chemiluminescence was positively correlated with the percentage of both capacitated and acrosome-reacted spermatozoa. The SOPR was negatively associated with the percentage of both capacitated and acrosome-reacted spermatozoa. In summary, this study showed that male rats exposed to lead had decreased serum testosterone levels and that this metal produced early onset of capacitation by one of the pathways of ROS generation. These effects might consequently result in premature acrosome reaction and reduced zona-intact oocyte-penetrating capability. 相似文献
6.
Jeffrey A. Pitt Michael J. Zoellner Edward W. Carney 《Reproductive toxicology (Elmsford, N.Y.)》1997,11(6):771-779
Lipopolysaccharide (LPS) was used to induce maternal hypozincemia in order to test the hypothesis that altered zinc homeostasis is developmentally toxic in the rabbit. Treatment of dams on Gestation Day (GD) 8 with LPS (0.67 μg/kg i.v.) caused total resorption of 78% (7 of 9) of the litters whereas GD 10 treatment increased the percentage of resorbed implantations (18-fold), but resulted in only 14% (1 of 7) totally resorbed litters. Cotreatment with zinc oxide (ZnO) on GD 10 decreased the resorption rate by 44%, indicating that hypozincemia was partially responsible for the resorptions. However, ZnO had no effect on resorption rate in GD 8 LPS-treated dams. No malformations were observed with LPS dosing on either gestation day. To determine whether LPS-induced Zn deficiency had any direct effects on rabbit embryos, normal GD 9 embryos were cultured for 48 h in serum from LPS-treated dams (0.53 ± 0.01 μg/mL Zn) or from controls (1.74 ± 0.07 μg/mL Zn). Embryo growth and development were normal in both groups, indicating a lack of any direct embryo effects of Zn deficiency. Finally, maternal plasma progesterone and the Zn content of conceptus tissues were measured 24 h after LPS injection on GD 10. Despite a marked decrease in maternal serum Zn, no significant changes in embryo, visceral yolk sac, yolk sac cavity-exoceolomic fluid, or placental Zn were found. However, maternal progesterone levels were decreased 33 and 28% in the LPS and LPS + ZnO groups, respectively. Taken together, these results indicate that rabbits may differ from rodent species in their lesser susceptibility to the teratogenic potential of transient maternal Zn deficiency, as well as in their resistance to conceptus Zn changes. Nonetheless, Zn deficiency may be responsible for an increase in resorption rate in the rabbit. 相似文献
7.
Recent studies have demonstrated that mammalian sperm are capable of generating reactive oxygen species (ROS) and that this activity is significantly accelerated in subfertile subjects. The observed decrease in penetration of zona-intact oocyte might be explained by chemical-induced ROS-related early onset of capacitation and premature acrosome reaction, but the mechanism is not clear. We determine whether zona-intact oocyte penetration capability in rat epididymal sperm was affected by premature acrosome reaction in rat sperm treated with hydrogen peroxide (H2O2) and calcium ionophore A23187 or H2O2 and lysophosphatidyl choline. Chlortetracycline fluorescence assay was used to study the status of acrosome reaction on epididymal sperm. The sperm-oocyte binding and penetration assay was used to evaluate the capability for zona pellucida penetration. There was a positive linear correlation between the frequency of acrosome-reacted sperm and capability of sperm-oocyte binding and penetration in zona-free oocytes. In the zona-intact oocytes, the sperm-oocyte penetration rate was suppressed as the proportions of acrosome-reacted sperm increased. In summary, this study showed that premature acrosome reaction reduced rat sperm's capability of penetrating zona-intact oocytes. However, this reduction is not seen in zona-free oocytes. These findings may provide a basis for understanding the effects of sperm ROS generation on zona pellucida penetration in male reproductive toxicology. 相似文献
8.
Conte JE Golden JA Kelley MG Zurlinden E 《International journal of antimicrobial agents》2005,26(6):449-456
The objective of this study was to determine the plasma and intrapulmonary pharmacokinetic parameters of intravenously administered meropenem in healthy volunteers. Four doses of 0.5 g, 1.0 g or 2.0 g meropenem were administered intravenously to 20, 20 and 8 healthy adult subjects, respectively. Standardised bronchoscopy and timed bronchoalveolar lavage (BAL) were performed following administration of the last dose. Blood was obtained for drug assay prior to drug administration and at the time of BAL. Meropenem was measured in plasma, BAL fluid and alveolar cells (ACs) using a combined high pressure liquid chromatographic–mass spectrometric technique. Plasma, epithelial lining fluid (ELF) and AC pharmacokinetics were derived using non-compartmental methods. Cmax/MIC90 (where Cmax is the maximum plasma concentration and MIC90 is the minimum inhibitory concentration required to inhibit 90% of the pathogen), AUC/MIC90 (where AUC is the area under the curve for the mean concentration–time data), intrapulmonary drug exposure ratios and percent time above MIC90 during the dosing interval (%T > MIC90) were calculated for common respiratory pathogens with MIC90 values of 0.12–4 μg/mL. In the 0.5 g dose group, the Cmax (mean ± S.D.), AUC0–8 h and half-life for plasma were, respectively, 25.8 ± 5.8 μg/mL, 28.57 μg h/mL and 0.77 h; for ELF the values were 5.3 ± 2.5 μg/mL, 12.27 μg h/mL and 1.51 h; and for ACs the values were 1.0 ± 0.5 μg/mL, 4.30 μg h/mL and 2.61 h. In the 1.0 g dose group, the Cmax, AUC0–8 h and half-life for plasma were, respectively, 53.5 ± 19.7 μg/mL, 55.49 μg h/mL and 1.31 h; for ELF the values were 7.7 ± 3.1 μg/mL, 15.34 μg h/mL and 0.95 h; and for ACs the values were 5.0 ± 3.4 μg/mL, 14.07 μg h/mL and 2.17 h. In the 2.0 g dose group, the Cmax, AUC0–8 h and half-life for plasma were, respectively 131.7 ± 18.2 μg/mL, 156.7 μg h/mL and 0.89 h. The time above MIC in plasma ranged between 28% and 78% for the 0.5 g dose and between 45% and 100% for the 1.0 g and 2.0 g doses. In ELF, the time above MIC ranged from 18% to 100% for the 0.5 g dose and from 25% to 88% for the 1.0 g dose. In ACs, the time above MIC ranged from 0% to 100% for the 0.5 g dose and from 24% to 100% for the 1.0 g dose. Time above MIC in ELF and ACs for the 2.0 g dose was not calculated because of sample degradation. The prolonged T > MIC90 and high intrapulmonary drug concentrations following every 8 h administration of 0.5–2.0 g doses of meropenem are favourable for the treatment of common respiratory pathogens. 相似文献
9.
目的:探讨卵子玻璃化冷冻技术在辅助生殖中的临床应用价值。方法回顾性分析2013年1月-2015年12月在解放军174医院生殖医学中心行体外受精,取卵日因男方因素未取到精子而行卵子玻璃化冷冻保存的27对不孕夫妇的资料。卵子解冻后均行夫精卵母细胞胞浆内单精子显微注射,记录卵子受精情况及临床结局。结果27例患者共冷冻卵子245枚,并全部解冻,解冻后存活214枚,存活率84.79%;其中第二次减数分裂中期( metaphase Ⅱ,MⅡ)卵198枚,并全部行ICSI,受精138枚,受精率74.49%;卵裂99枚,卵裂率71.74%;形成87枚2PN(原核,pronucleus)胚胎,优质胚胎34枚,优质胚胎率39?08%。20个移植周期移植胚胎41枚,临床妊娠6例,临床妊娠率34.82%。结论玻璃化冷冻技术应用于卵子冷冻保存,并对复苏卵子进行卵母细胞胞浆内单精子显微注射可以取得一定的临床妊娠率,在辅助生殖技术临床上具有很强的实用价值。 相似文献
10.
Li-jun CHEN Wan-de LI Shi-feng LI Xing-wen SU Guang-yun LIN Yi-jun HUANG Guang-mei YAN 《Acta pharmacologica Sinica》2010,31(5):554-559
Aim:
To investigate the mechanism of bleomycin (BLM)-induced pulmonary fibrosis.Methods:
Cultured human fetal lung fibroblast (HLF) cells were exposed to bleomycin (BLM) at 0–30 μg/mL for 24 h. Western blot analysis was used to detect lysyl oxidase (LO) protein expression. Real-time RT-PCR was used to detect LO mRNA level. LO catalytic activity was measured using diaminopentane as a substrate and Amplex red as a hydrogen peroxide probe. Copper (Cu) concentration was detected by flame atomic absorption spectrophotometry.Results:
Exposure of HLF cells to BLM at 10 μg/mL and 30 μg/mL increased LO catalytic activity to 130% and 158% of the control in the conditioned media. The expression of LO mRNA was increased to 5.5-fold of the control in HLF cells exposure to BLM at 3 μg/mL. BLM at 3 μg/mL also increased the expression of 46 kDa preproLO, 50 kDa proLO and 32 kDa mature LO to 219%, 130%, and 135% of the control, respectively. The Cu concentrations in conditioned media of cultured HLF cells exposed to BLM (10 and 30 μg/mL) were increased significantly to 1.48 and 2.46-fold of the control, respectively.Conclusion:
Bleomycin induces upregulation of LO in cultured human fetal lung fibroblasts, which may be the mechanism of bleomycin-induced pulmonary fibrosis. 相似文献11.
The whole embryo culture system has proved particularly useful in evaluating the role of biotransformation in dysmorphogenic processes. Using the traditional method, information on the teratogenic potential of chemicals can be obtained, but the results are difficult to extrapolate to humans. In this study, a human liver S-9 fraction was used as an enzyme source for the bioactivation of cyclophosphamide (CP) in vitro, to assess whether this model mimics more nearly the human situation. CP is a well known rodent teratogen but probably is not teratogenic in humans. The effects were compared of Aroclor-1254-induced rat liver S-9, non-induced rat liver S-9 and human liver S-9 fractions on CP teratogenicity in vitro. CP (30 μg/ml) with non-induced rat S-9 (50 μl) did not cause a significant increase in adverse effects (46.7%), whereas 100% dysmorphogenic effects were shown with induced rat S-9 (30 μl, 50 μl). CP (30–150 μg/ml) did not produce dysmorphogenesis (below 35.5%) in the presence of human S-9 (50 μl). 相似文献
12.
One objective of these experiments was to establish a sensitive assay to evaluate fertilizing potential of rat gametes in vitro. A second objective was to evaluate this in vitro fertilization (IVF) assay as a method to detect in vivo effects of reproductive toxicants on male and female gametes using three known reproductive toxicants as model systems. The IVF assay with zona-free oocytes was more precise than the assay with cumulus-intact oocytes in these studies (coefficients of variation of 8.7 and 14.4%, respectively). Sperm fertilizing potential for zona-free oocytes was reduced by treatment of rats with m-dinitrobenzene (10-10 000 microg/kg) and ethylene glycol monomethyl ether (50-100 mg/kg) that had no effect on sperm motility. Molinate (60 mg/kg for 5 days) reduced sperm fertilizing potential concurrently with reductions in sperm motility. Neither molinate (60 mg/kg for 5 days) nor dinitrobenzene (0.002% in the drinking water for 14 days) administered to females seemed to affect the fertilizability of their oocytes. Ethylene glycol monomethyl ether treatment (0.15-0.25% in the drinking water for 14 days) reduced the number of ovulated oocytes. IVF is a means to evaluate toxicant effects on female gametes and demonstrates sperm's ability to interact with the oocyte plasma membrane. 相似文献
13.
目的 探讨短时受精精卵共孵育时间对受精率的影响.方法 170例行体外受精-胚胎移植( IVF-ET)患者常规促排卵,依据精卵共孵育时间分为短时受精组(A组:57例,精卵共孵育2~3h;B组:58例,精卵共孵育4~5h)和常规受精组(C组:55例,精卵共孵育18 h );之后将卵子转移至新鲜培养基中.比较各组的受精率、卵裂率、优胚率、临床妊娠率、胚胎种植率.结果 三组受精率分别为63.01%、71.43%和78.72%,各组间的差异有统计学意义(P<0.05);C组的卵裂率、优胚率均低于A组和B组;C组与A组的卵裂率[97.05% vs 99.25%]、C组与B组的优胚率[37.14%vs 44.42%]之间的差异有统计学意义(P<0.05);各组间临床妊娠率、胚胎种植率差异无统计学意义(P> 0.05).结论 短时受精有助于提高卵裂率、优胚率,精卵共孵育时间4~5h的受精率较2~3h高. 相似文献
14.
Tamil IG Dineshkumar B Nandhakumar M Senthilkumar M Mitra A 《Indian journal of pharmacology》2010,42(5):280-282
Objective:
The objective of this study was to evaluate the α-amylase inhibitory activity of different extracts of Phyllanthus amarus against porcine pancreatic amylase in vitro.Materials and Methods:
The plant extracts were prepared sequentially with ethanol, chloroform, and hexane. Each extract was evaporated using rotary evaporator, under reduced pressure. Different concentrations (10, 20, 40, 60, 80, and 100 μg/mL) of each extract were made by using dimethyl sulfoxide (DMSO) and subjected to α-amylase inhibitory assay using starch azure as a substrate. The absorbance was read at 595 nm using spectrophotometer. Using this method, the percentage of α-amylase inhibitory activity and IC50values of each extract was calculated.Results:
The chloroform extract failed to inhibit α-amylase activity. However, the ethanol and hexane extracts of P. amarus exhibited appreciable α-amylase inhibitory activity with an IC50 values 36.05 ± 4.01 μg/mL and 48.92 ± 3.43 μg/mL, respectively, when compared with acarbose (IC50value 83.33 ± 0.34 μg/mL).Conclusion:
This study supports the ayurvedic concept that ethanol and hexane extracts of P. amarus exhibit considerable α-amylase inhibitory activities. Further, this study supports its usage in ethnomedicines for management of diabetes. 相似文献15.
Aim:
To assess the cytotoxic effect of crotoxin (CrTX), a potent neurotoxin extracted from the venom of the pit viper Crotalus durissus terrificus, in human lung adenocarcinoma A549 cells and investigated the underlying mechanisms.Methods:
A549 cells were treated with gradient concentrations of CrTX, and the cell cycle and apoptosis were analyzed using a flow cytometric assay. The changes of cellular effectors p53, caspase-3 and cleaved caspase-3, total P38MAPK and pP38MAPK were investigated using Western blot assays. A549 xenograft model was used to examine the inhibition of CrTX on tumor growth in vivo.Results:
Treatment of A549 cells with CrTX (25–200 μg/mL) for 48 h significantly inhibited the cell growth in a dose-dependent manner (IC50=78 μg/mL). Treatment with CrTX (25 μg/mL) for 24 h caused G1 arrest and induced cell apoptosis. CrTX (25 μg/mL) significantly increased the expression of wt p53, cleaved caspase-3 and phospho-P38MAPK. Pretreatment with the specific P38MAPK inhibitor SB203580 (5 μmol/L) significantly reduced CrTX-induced apoptosis and cleaved caspase-3 level, but G1 arrest remained unchanged and highly expressed p53 sustained. Intraperitoneal injection of CrTX (10 μg/kg, twice a week for 4 weeks) significantly inhibited A549 tumor xenograft growth, and decreased MVD and VEGF levels.Conclusion:
CrTX produced significant anti-tumor effects by inducing cell apoptosis probably due to activation of P38MAPK and caspase-3, and by cell cycle arrest mediated by increased wt p53 expression. In addition, CrTX displayed anti-angiogenic effects in vivo. 相似文献16.
不同来源精子卵胞浆内单精子注射治疗男性不育 总被引:1,自引:0,他引:1
目的分析用3种不同来源精子行卵细胞浆内单精子注射(ICSI)治疗不育158个周期。方法女方进行常规超排卵.用射出精子。经皮附睾精子抽吸术(PEsA)或睾丸精子抽吸术(TESE)获得的精子行ICSI治疗男性不育共158个周期。结果射出精子组110个治疗周期其受精率、卵裂率、优质胚胎率、胚胎种植率和临床妊娠率为67.3%,95.2%,50.2%,20.5%和35.5%。附睾精子组38个治疗周期其受精率、卵裂率、优质胚胎率、胚胎种植率和临床妊娠率为63.5%,95.7%,60.1%,20.2%和47.4%。睾丸精子组10个治疗周期其受精率、卵裂率、优质胚胎率、胚胎种植率和临床妊娠率为68.8%,96.1%。35.1%,17.2%和30%。3组结果比较,差异无显著性意义。结论不论通过手淫取精,PESA或TESE,只要能获得活动精子,结合ICSI,各种因素的男性不育患者均有机会获得妊娠。 相似文献
17.
Tseng YL Uralets V Lin CT Kuo FH 《Journal of pharmaceutical and biomedical analysis》2005,39(5):1042-1045
The main purpose of this study was to detect and quantify modafinil in human urine by gas chromatography–mass spectrometry (GC–MS). Urinary samples were collected from three healthy male volunteers following oral administration of a clinical dose (100 mg) of modafinil (Provigil®). Urine specimens were extracted with t-butylmethyl ether (TBME) prior to GC–MS analysis. The results demonstrate that the chromatographic characteristics and the mass spectrum of the unchanged parent drug extracted from urine samples were identical to that obtained from the authentic standard. The times for the unchanged modafinil to reach peak concentration in the urine of the three volunteers were at 2 h (6.14 μg/mL), 4 h (9.93 μg/mL) and 8 h (3.58 μg/mL), respectively. Total clearance occurred in approximately 48–72 h with 2–5% eliminated through urine as unchanged modafinil. The present study demonstrates that modafinil is detectable in the absence of hydrolysis and derivatization steps. 相似文献
18.
Conte JE Golden JA Kelly MG Zurlinden E 《International journal of antimicrobial agents》2005,25(6):523-529
The steady-state serum and intrapulmonary pharmacokinetic and pharmacodynamic parameters of tigecycline were determined after intravenous administration in 30 subjects. Tigecycline was administered as a 100 mg loading dose followed by six 50 mg doses given every 12 h and was measured using HPLC/mass spectrometry. Ratios of tigecycline maximum serum concentration and area under the serum concentration–time curve to 90%—minimum inhibitory concentrations (Cmax/MIC90; AUC/MIC90), and percentage time above MIC90 were calculated for common respiratory pathogens (Streptococcus pneumoniae, Chlamydia pneumoniae, Mycoplasma pneumoniae, Moraxella catarrhalis and Haemophilus influenzae). The Cmax (mean ± S.D.), AUC and half-life for serum were 0.72 ± 0.24 μg/mL, 1.73 ± 0.64 μg*h/mL and 15.0 ± 1.10 h; for lung epithelial lining fluid (ELF) the values were 0.37 μg/mL, 2.28 μg*h/mL and 39.1 h; and for alveolar cells (AC) were 15.2 μg/mL, 134 μg*h/mL and 23.7 h. Tigecycline was concentrated in AC: Cmax/MIC90 ratios ranged from 30.4 (H. influenzae) to 507 (S. pneumoniae); AUC/MIC90 ratios ranged from 268 (H. influenzae) to 4467 (S. pneumoniae); and percentage dose interval above MIC90 was 100% for the five respiratory pathogens. The Cmax/MIC90, AUC/MIC90 ratios, T > MIC90 and extended serum and intrapulmonary half-lives following the regimen used in this study are favourable for the treatment of tigecycline-susceptible pulmonary infections. 相似文献
19.
目的比较常规体外受精(IVF)和卵胞浆内单精子注射(ICSI)两种受精方式对无明确男性因素的周期获卵数仅为1-3个患者的治疗结局的影响。方法回顾性分析IVF-胚胎移植周期中获卵数1-3个周期共403个,按受精方式分为常规IVF组(336个周期)与ICSI组(67个周期)。比较两组受精率、正常受精率、完全不受精周期率及临床妊娠率的差异。结果 IVF组正常受精率为71.54%,低于ICSI组的80.31%(P<0.05)。IVF组完全不受精周期率、受精率、卵裂率、种植率和妊娠率分别为10.42%、85.50%、97.93%、26.00%和34.93%,ICSI组分别为10.45%、82.68%、98.01%、19.10%和26.32%,两组间差异无统计学意义(P>0.05)。结论鉴于使用ICSI技术并不能提高种植率及妊娠率,建议对于无明确男性因素的周期获卵1-3个的仍可采用IVF。 相似文献
20.
The influence of the mycotoxins deoxynivalenol and zearalenol on in vitro maturation of pig oocytes and in vitro culture of pig zygotes 总被引:4,自引:0,他引:4
The aim of the present study was to investigate the influence of specific toxins on in vitro maturation and embryo culture. - and β-zearalenol were tested at increasing levels from 3.75 to 90 μ
and deoxynivalenol from 0.94 to 7.5 μ
in order to evaluate the effect on in vitro maturation rate of porcine cumulus–oocyte complexes. Furthermore, the influence of -zearalenol (3.75–30 μ
) was appraised on the developmental competence of in vivo-derived zygotes during 5 days of in vitro culture. All three substances affected maturation and degeneration rates in a dose-dependent manner, but to different extents. Significant differences were obtained at a concentration of 7.5 μ
-zearalenol and higher. β-zearalenol negatively affected the process of oocyte development beginning at a concentration of 30.0 μ
(P<0.05). Deoxynivalenol had significant influence on oocyte maturation at a concentration of 1.88 μ
(31.4 vs 79.3% for control). Differences in embryonic development in vitro were observed at a concentration of 15 μ
-zearalenol (P<0.05). These data demonstrate a negative effect of -zearalenol on embryonic development of zygotes, and a compound-specific, dose-dependent negative effect of the three substances on meiotic progression of porcine oocytes. 相似文献