Different effects on hemesynthesis in male and female rabbits treated with lead acetate

The feasibility of an animal model was investigated to study the mechanisms underlying the difference in response to inorganic lead exposure between males and females, as shown in the different increase of zincprotoporphyrin (ZPP) in blood concentrations. Groups of rabbits of both sexes received s.c. injections of 0.25 (L) or 0.50 (H) mg lead acetate/kg b.w. or a control solution three times a week during 14 weeks. A steep increase of blood lead (PbB) was found in the first 4 weeks of exposure; in subsequent weeks PbB leveled off. In the L-group PbB increased to 775–1387 /1 rbc and in the H-group to 892–1522 g/l rbc. In female rabbits ZPP increased earlier than in males; the relative increase of ZPP was stronger in female rabbits, particularly in the H-group. No effect on Hb, Ht and body weight was observed. The response to lead in female and male rabbits is very similar to that observed in humans.     

The effect of testosterone administration on lead induced zincprotoporphyrin in blood concentration in castrated male rabbits

The influence of testosterone propionate on the concentration of Zincprotoporphyrin in blood (ZPP) of castrated lead treated rabbits was investigated. The experimental design allowed comparison of the relative ZPP increase (RZI) in testosterone treated and non testosterone treated rabbits. Testosterone was administered by subcutaneous injection of 3 mg/kg body weight/day for 7 consecutive days directly prior to the lead exposure, which was performed by subcutaneous injection of 0.50 mg leadacetate/kg body weight, three times a week for 7 weeks. No effect was found on the hemoglobin concentration (Hb) and hematocrit (Ht) and on the increase of body weight during the experiment. But the increase of RZI in the non testosterone treated rabbits was significantly steeper and earlier than in the testosterone treated group. The possible consequences of the findings had been further commented on.     

Absence of an effect of lead acetate on sperm morphology,sister chromatid exchanges or on micronuclei formation in rabbits

The influence of lead on sperm morphology, sister chromatid exchanges or on micronuclei formation was studied on male rabbits after exposure to doses of 0, 0.25, and 0.50 mg lead acetate/kg body weight subcutaneously injected three times a week during 14 weeks, each on a group of five rabbits. At the end of exposure phase the lead in blood concentrations of the three groups of rabbits were 0.32, 2.57, and 2.97 mol/l respectively. The results did not show any evidence of treatment related effects on sperm count or on morphologic abnormalities of the sperms, neither on the histopathology of the testis. Statistical analysis of the number of sister chromatid exchanges per metaphase in lymphocytes indicated no differences between the groups. Also no dose dependent effect was observed on the relative number of micronuclei in bone marrow erythrocytes. The different susceptibility to lead in different organ systems of the rabbits was discussed.     

不同药物方案治疗幽门螺杆菌阳性慢性胃炎活动期患者的临床疗效及安全性

目的 探讨三联药物、四联药物及序贯药物方案治疗幽门螺杆菌（Hp）阳性慢性胃炎活动期患者的临床疗效及安全性。方法 选取2015年6月至2017年6月河南省南阳医学高等专科学校第一附属医院收治的Hp阳性慢性胃炎活动期患者180例,采用随机数字表法分为A组、B组及C组3组,每组60例,分别采用三联药物、四联药物及序贯药物方案治疗;比较3组患者疼痛缓解率,症状缓解时间、Hp根除率、不良反应发生率,随访12个月,比较3组患者的复发率。结果 C组疼痛缓解率高于A、B组,疼痛和消化道症状缓解时间短于A、B组,Hp根除率高于A、B组,差异均有统计学意义（P<0.05）;C组不良反应发生率低于A、B组,差异有统计学意义（P<0.05）;C组随访6个月和12个月复发率均低于A、B组,差异有统计学意义（P<0.05）。结论 序贯药物方案治疗Hp阳性慢性胃炎活动期能够有效缓解疼痛,促进症状改善,提高Hp根除率,避免远期复发,并有助于降低不良反应发生风险,优于三联和四联药物方案。     

醋酸铅体外染毒对移植后小鼠胚泡发育的影响

目的　用胚胎移植技术评价醋酸铅对啮齿类动物的生殖毒性。方法　采用 2 0和 40 μg mL浓度的醋酸铅对小鼠着床前胚胎进行体外染毒 ,将染毒后可胚泡化的胚胎移植于假孕母鼠体内继续生长发育 ,观察出生前胎鼠形态学改变和出生后子鼠的行为改变 ,并对子鼠大脑进行病理检查。结果　 ( 1)在实验剂量下 ,各染毒组出生前胎鼠形态学检查未见异常。 ( 2 ) 40 μg mL醋酸铅染毒组子鼠出现行为异常 ;回旋运动、阴性趋地运动、翻正反射和断崖回避阳性日均迟于阴性对照组 (P <0 0 5、P <0 0 1、P <0 0 5、P <0 0 5 ) ;悬挂时间明显短于阴性对照组 (P <0 0 5 ) ;10日龄游泳积分低于阴性对照组 (P <0 0 1)。 ( 3 )电镜超微结构显示各染毒组子鼠大脑中毒性损伤。结论　小鼠植入前胚泡体外醋酸铅染毒影响移植子鼠的行为功能 ,并引起中枢神经组织病理损伤 ;胚胎移植技术用于检测化学物胚胎毒性 ,排除母体因素的干扰 ,是一重要研究手段     

Reversal learning deficits in young monkeys exposed to lead.

The reversal learning capacity of young rhesus monkeys in visual discrimination tasks was examined during daily exposure to dietary lead acetate throughout the first year of life. While not affected in physical development, all lead-treated monkeys showed performance deficits on reversal learning tasks. These deficits were independent of lead-induced changes in motivation. Over a series of problems, the overall learning rate of monkeys with blood lead concentrations in the range of 70-90 microgram/dl was retarded, which resulted partly from a pronounced difficulty in attaining criterion on the first of a series of reversals within a given problem. This latter deficit resulted from an increase in errors, balks, and total trials to criterion on the first reversal. Monkeys exposed to blood lead concentrations of 40-60 microgram/dl required significantly more trials to finish all problems, but did not show the first-reversal deficit. Theoretical implications of these data were discussed.     

Protective role of flax lignans against lead acetate induced oxidative damage and hyperlipidemia in rats

The results showed that the lead concentration was higher than Cr, Ni and Cd in roadside soil samples. Also, the present study was conducted to investigate the protective role of flax lignans against the effects of lead acetate on oxidative stress, antioxidant enzymes and lipid profile. Animals were divided into three groups; the first group was used as control. While, groups 2, and 3 were orally treated with 200 mg/L lead acetate in drinking water and the combination of lead acetate (200 mg/L) plus flax lignans (30 mg/100 g BW), respectively. Rats were administered their respective doses daily for 3 weeks. Results showed that lead acetate increased TBARS, and decreased the activities of GST, SOD, GR and CAT, and the contents of glutathione in liver extracts, compared to control. The present data indicated that total lipids, cholesterol, triglycerides and LDL-c were significantly increased by lead acetate treatment, while HDL-c levels were decreased in the serum and liver extracts. Animals treated with flax lignans in combination with lead acetate alleviated its toxic effects in the tested parameters. Also, the morph metric analysis of the dorsal aorta revealed that, the histological alterations induced after lead acetate treatments were markedly reduced.     

鲑鱼降钙素治疗76例老年骨质疏松症的临床效果观察

目的分析对老年骨质疏松症患者应用鲑鱼降钙素进行治疗的临床效果。方法选取我院近3年收治的老年骨质疏松症患者76例,随机将其分为A、B两组,其中A组应用鲑鱼降钙素联合钙尔奇D进行治疗,B组应用钙尔奇D进行治疗,对比A、B两组患者的临床效果、骨密度、疼痛改善情况以及生活质量。结果A组患者的总有率以及疼痛缓解率均明显高于B组,其差异存在统计学意义（P〈0．05）,此外,A组患者经过治疗后,其骨密度明显增加,差异存在统计学意义（P〈0．05）,而B组患者在治疗前后,骨密度没发生多大的变化。结论对老年骨质疏松症患者临床应用鲑鱼降钙素治疗,不仅可以取得良好的效果,还能够缓解患者疼痛情况,并且提高患者的生活与工作质量,具有很多优势,值得各大医院临床推广使用。     

醋酸汞和醋酸铅对大鼠间质细胞功能的影响

研究结果发现，醋酸汞Ｈｇ２＋（１０－８－１０－５ｍｏｌ／Ｌ）和醋酸铅Ｐｂ２＋（１０－７－１０－４ｍｏｌ／Ｌ）分别使得经ｈＣＧ（１００ｍＩＵ）刺激处理２４小时的Ｌｅｙｄｉｇ细胞内ｃＡＭＰ含量显著下降；同时Ｈｇ２＋（１０－７－１０－５ｍｏｌ／Ｌ）和Ｐｂ２＋（１０－６－１０－４ｍｏｌ／Ｌ）也使得Ｌｅｙｄｉｇ细胞Ｔ含量明显降低并且具有明显的剂量－反应关系。醋酸锌（Ｚｎ２＋）对原代培养的Ｌｅｙｄｉｇ细胞的上述观察指标均无影响，表明用这些指标的变化可以评价Ｈｇ２＋和Ｐｂ２＋对大鼠睾丸Ｌｅｙｄｉｇ的某些毒性。     

慢性心力衰竭的临床指标学特点研究

目的探讨慢性心力衰竭多项指标与非慢性心衰组的差异,为今后慢性心力衰竭的早期发现、早期诊断提供一些基本的理论依据,以降低心力衰竭的死亡率。方法 2012年6月到2012年12月本院共收集心力衰竭患者50例,非心力衰竭患者31例,依次对二组的多项指标做统计学分析。结果心衰患者与非心衰患者的综合比较发现,在CHOL、TG、HDL-C、LDL-C、ALT以及AST等生化指标上并没有特异性,在ANG-II、ET-1、IL-β以及TNF四个指标上,可以较为明显的看出,心衰组均明显的高于其他组,在ANG-II,CYPA心衰组的值明显的高于非心衰组。结论慢性心力衰竭并不能通过其血清常规生化指标来反应,而指标特征主要表现在ANG-II、ET-1、IL-β、CYPA以及TNF中。     

Taurine mitigates cognitive impairment induced by chronic co-exposure of male Wistar rats to chlorpyrifos and lead acetate

Organophosphate pesticides and heavy metals are ubiquitous environmental pollutants and neurotoxicants. We investigated the effects of taurine (an antioxidant; TA) on oxidative stress and cognition in male Wistar rats co-treated with chlorpyrifos (an organophosphate pesticide; CPF) and lead acetate (heavy metal; LA). The Wistar rats were divided into 5 groups of 10 rats each. The first two groups were administered with distilled water and soya oil respectively. The remaining three groups were administered with taurine (TA), 50 mg/kg body weight, CPF + LA group [CPF (4.25 mg/kg, 1/20 LD50] and LA (233.25 mg/kg, 1/20 LD50) and TA + CPF + LA group [TA (50 mg/kg), CPF (4.25 mg/kg) and LA (233.25 mg/kg)]. The xenobiotics were administered once daily by oral gavage for 16 weeks. The results showed reductions in the activities of brain antioxidant enzymes and acetylcholinesterase, increased lipoperoxidation and histopathological alterations of the cerebral cortex in the CPF + LA group. However, TA mitigated perturbations in the activities of the antioxidant enzymes and acetylcholinesterase, counteracted oxidative stress and brain lipoperoxidation and attenuated neuronal degeneration induced by joint CPF and LA-induced neurotoxicity. The results suggested that TA is neuroprotective following chronic co-exposure of rats to CPF and LA.     

Effects of chronic administration of tobacco smoke to mice: Behavioral and metabolic measures

Tobacco smoke was administered to male and female mice of four inbred strains and two lines selectively bred for high activity (HA) or low activity (LA) in an open field. Administration occurred during 14 daily 10-min pretreatment sessions in a box filled with smoke from a nonfiltered cigarette (2 mg nicotine/ cigarette; average density, 750 ppm carbon monoxide). When open-field activity was subsequently measured in the absence or presence of smoke (average density, 150 ppm carbon monoxide), pretreated mice had significantly lower activity scores than controls. Comparisons of open-field activity scores under smoke-present and smoke-absent conditions revealed that effects of this acute exposure were dependent upon genotype: C3H/2Ibg activity was almost tripled in the presence of smoke; DBA/2Ibg activity was increased; but HA, LA, and C57BL/6Ibg activity scores were depressed. As measured by open-field activity, development of tolerance to the effects of acute exposure to tobacco smoke after chronic pretreatment was also genotype-dependent.Significant genotypic differences were found for nicotine remaining in liver, brain, and blood samples when mice were sacrificed 2.5 or 5 min after a weight-specific injection of radiolabeled nicotine. Tissue nicotine levels were also related to sex, time after injection, and pretreatment interactions with genotype. Strong positive correlations were found between the measures of brain and liver levels at 5 min after injection and the behavioral measure of open-field activity under the smoke-present condition.     

Electrophysiologic effects of flecainide relative to serum and tissue concentrations in rabbits after chronic drug administration

The effects of chronic treatment with flecainide on the cellular electrophysiology and the relationship of the electrophysiologic effects to serum and myocardial flecainide concentrations were determined in rabbit ventricular myocardium. Two groups of rabbits were administered flecainide at doses of 7.5 mg/kg body weight (dose I) and 20 mg/kg body weight (dose II) intraperitoneally (i.p.) twice daily for 12-14 days; a third group received saline. Serum and myocardial flecainide concentrations with dose II (0.44 +/- 0.15 micrograms/ml and 3.0 +/- 1.4 micrograms/g, respectively) were significantly (p less than 0.01) higher than with dose I (0.19 +/- 0.11 micrograms/ml and 0.81 +/- 0.15 micrograms/g, respectively). At 1.0-Hz stimulation, only the high dose produced significant changes in transmembrane action potentials of right ventricular myocardial fibers, which showed a 17.6% (n = 6, p less than 0.05) decrease in maximal upstroke velocity (Vmax) of phase 0 and 19.5% (n = 6, p less than 0.05) prolongation of effective refractory period (ERP). Repetitive stimuli led to an exponential decline in Vmax with both dosage regimens. The magnitude of Vmax decrease was frequently dependent and was greater with the higher dose. The rate of decrease of Vmax per action potential (AP) during train of stimuli in rabbits treated with dose II was 0.037 +/- 0.012 (n = 5) at 2.0-Hz stimulation, and the recovery time constant from use-dependent block at 4.0-Hz stimulation increased significantly from 12.6 +/- 3.6% decrease in Vmax with the low dose to 35.6 +/- 7.1% decrease with the high dose. The data show that sodium channel inhibition by chronic flecainide administration is a function of dose, serum, and myocardial flecainide concentrations.     

醋酸去氨加压素经家兔眼部给药后的药动学及药效学研究

比较醋酸去氨加压素经家兔眼部给药、静脉注射以及灌胃给药后的药动学及药效学特征,探索多肽类药物通过眼部给药进入全身循环的可行性。15只家兔随机分成3组(眼部给药, 7.0μg·kg^-1;静脉注射, 0.7μg·kg^-1;灌胃给药, 7.0μg·kg^-1),给药后按预定时间点心脏取血,采用酶联免疫法(ELISA)测定醋酸去氨加压素的血药浓度;另21只家兔随机分成3组(眼部给药, 7.0μg·kg^-1;静脉注射, 0.7μg·kg^-1;灌胃给药, 7.0μg·kg^-1)进行药效学研究,在给药前和给药后的预定时间段收集尿液。家兔静脉注射给药后峰浓度(C_max)为143.0 pg·mL^-1,血药浓度-时间曲线下的面积(AUC_0-t)为999.9 pg·h·mL^-1;眼部给药后达峰时间(t_max)为5 min, C_max为125.6 pg...     

The central effects of paraoxon on blood pressure of rabbits after intravenous administration or infusion via a vertebral artery

In the present study paraoxon (28–825 g/kg, i.v.) was administered into rabbits treated with N-methylatropine (1 mg/kg). In urethane-anaesthetized rabbits pressor and depressor effects were observed. In pentobarbitone-anaesthetized rabbits, however, only depressor effects were noticed. Dexetimide (0.25–0.5 mg/kg) prevented the pressor and depressor action of paraoxon. Furthermore, paraoxon (83–825 g) was infused into a vertebral artery of pentobarbitone-anaesthetized animals. After administration via this route the depressor effect was similar to i.v. administration. 30 min after administration of paraoxon acetylcholinesterase activity was determined in the medulla oblongata, the pons and the hypothalamus. The enzyme has to be inhibited almost completely to induce an effect on blood pressure.It is concluded that the vascular effects of paraoxon seem to be mediated by a mechanism involving stimulation of central muscarinic receptors, probably by accumulated acetylcholine, which in turn induces a decrease in blood pressure.     

痰热清注射液治疗慢性支气管炎急性发作的临床疗效

目的研究在治疗慢性支气管炎急性发作期使用痰热清注射液的临床效果。方法将本院呼吸科2011年2月～2012年6月收治住院的慢性支气管炎急性发作期患者60例分为A组和B组,分别予以一般基础治疗（包括抗感染、平喘、祛痰等）和加用痰热清注射液治疗。结果分别治疗1个疗程后,A组的总有效率为60%,症状缓解时间为（8.6±0.4）d,B组的总有效率为90%,症状缓解时间为（4.3±0.7）d。经统计学分析,P均〈0.05,差异均有统计学意义。结论在治疗慢性支气管炎急性发作期过程中加用痰热清注射液,不仅可以提高临床治疗效果,同时还可以迅速起效,缩短治疗时间,值得临床推广应用。     

Activity of glutathione-S-transferase in rat liver and kidneys after administration of lead or cadmium

The influence of an acute dose of lead nitrate or cadmium chloride on the activity of glutathione-S-trans-ferase (GST) was investigated in rats. CdCl₂ (10 mol/kg) did not influence the enzyme activity in either organ. In contrast Pb(NO₃)₂ (100 mol/kg) caused a significant increase of GST activity in both organs. SDS polyacrylamide gel electrophoresis (SDS-PAGE) showed that in liver the activity enhancement is due mainly to the induction of the isoenzyme GST 7-7, while in the kidneys the activity of all the isoenzymes is increased.     

Considerations when using longitudinal cohort studies to assess dietary exposure to inorganic arsenic and chronic health outcomes

Dietary arsenic exposure and chronic health outcomes are of interest, due in part to increased awareness and data available on inorganic arsenic levels in some foods. Recent concerns regarding levels of inorganic arsenic, the primary form of arsenic of human health concern, in foods are based on extrapolation from adverse health effects observed at high levels of inorganic arsenic exposure; the potential for the occurrence of these health effects from lower levels of dietary inorganic arsenic exposure has not been established. In this review, longitudinal cohort studies are evaluated for their utility in estimating dietary inorganic arsenic exposure and quantifying statistically reliable associations with health outcomes. The primary limiting factor in longitudinal studies is incomplete data on inorganic arsenic levels in foods combined with the aggregation of consumption of foods with varying arsenic levels into a single category, resulting in exposure misclassification. Longitudinal cohort studies could provide some evidence to evaluate associations of dietary patterns related to inorganic arsenic exposure with risk of arsenic-related diseases. However, currently available data from longitudinal cohort studies limit causal analyses regarding the association between inorganic arsenic exposure and health outcomes. Any conclusions should therefore be viewed with knowledge of the analytical and methodological limitations.     

Nephrotoxic effects of chronic administration of microcystins -LR and -YR.

Acute intoxication with MC-LR induces cytoskeletal alterations, apoptosis and necrosis of hepatocytes resulting in intrahepatic hemorrhage. Preliminary results have shown that chronic treatment of rats with intraperitoneal injections of sublethal doses of microcystins MC-LR and MC-YR could induce not only liver, but also kidney injuries. We aimed to investigate whether the induction of the cytoskeletal changes, apoptosis and necrosis could be the mechanisms involved in the injury of kidney cells in the chronic model of microcystin intoxication. Experimental rats were receiving intraperitoneal injections of MC-LR (10 microg/kg) or MC-YR (10 microg/kg) every second day for 8 months, while control rats were receiving only the vehicle. The histopathological investigation revealed collapsed glomeruli with thickened basement membranes and dilated tubuli filled with eosinophilic casts. Rhodamine-phalloidin labeling showed cytoplasmic aggregation and accumulation of fibrilar actin filaments within the epithelial tubular cells. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) showed increased number of TUNEL-positive cells in the kidney cortex and medulla. The pathological changes induced by MC-LR appeared more severe than those induced by MC-YR. The results support the view that at the cellular level, the mechanisms that underly the chronic nephrotoxicity are similar to the mechanisms of the acute hepatotoxicity of microcystins.     

铅和噪声联合作用对作业工人血SOD、MDA含量的影响

目的 探讨铅和噪声联合作用对工人的血清超氧化物歧化酶（SOD）、丙二醛（MDA）含量的影响.方法 选择年龄、工龄及接触噪声强度相近的A（铅和噪声联合作用组）、B（单纯噪声组）两组工人,测定血SOD、MDA含量,同时测定血铅含量,并比较两组数据差异.结果 A、B两组工人血SOD值分别为（65.2±16.3） U/ml、（63.8±13.9） U/ml,两组工人血SOD值无明显差异（P＞0.05）;A、B两组工人血MDA含量分别为（6.81±3.12）nmol/ml、（5.02±2.36）nmol/ml,两组工人血MDA含量差异有统计学意义（P＜0.05）.结论 铅和噪声联合作用可加重机体自由基损害和脂质过氧化.