Cadmium nephrotoxicity and evacuation from the body in a rat modeled subchronic intoxication

BACKGROUND: Cadmium (Cd) is an important industrial pollutant, although its mechanism of toxicity has not been completely clarified. We studied Cd-induced subchronic nephrotoxicity and the cadmium evacuation system in rats and cultured human renal tubular cells. METHODS: Male Sprague-Dawley rats were subcutaneously injected with 0.6 mg Cd/kg per day for periods of 3, 5 and 8 weeks. The concentration of Cd in urine, serum and kidneys was measured by atomic absorption spectrophotometry. Nephrotoxicity was evaluated based on the urinary concentration of beta2 microglobulin (B2MG) and histopathological findings. Apoptotic cells were detected by nick-end labeling and DNA laddering, and were based on the level of caspase-3 activity. Cadmium-induced toxicity was also studied in cultured human renal tubular cells. RESULTS: Nephrotoxicity was detected after 4 weeks of exposure to Cd, because Cd and B2MG appeared in urine. The tissue concentration of Cd increased linearly throughout the 8 weeks of exposure to Cd. The concentration of renal Cd did not change in the 3-week exposure group, but it decreased after withdrawal of Cd in the 5-week exposure group, suggesting an active Cd excretion mechanism started after the 4th week. The threshold Cd concentration for nephrotoxicity was 150 micrograms/gram wet tissue, at which concentration histological tubular damage started. Although the kidneys presented mainly necrosis, apoptosis was observed at weeks 4 and 5, before renal tubular necrosis occurred. In vitro DNA laddering was observed and peak caspase-3 activity was detected when the cells were exposed to the threshold concentration of Cd. CONCLUSION: Cadmium was effectively evacuated from the body by exfoliation of damaged renal tubular cells presenting focal tubular necrosis after the renal Cd concentration reached the threshold. Apoptosis may be involved in the regulation of Cd-induced nephrotoxicity.     

Effects of simulated Fowler-Stephens orchiopexy on testicular structure and function in rats.

To determine the effects of the Fowler-Stephens orchiopexy (FSO) on testicular structure and function, young rats underwent simulated FSO and concurrent contralateral orchiectomy, unilateral orchiectomy, or no operation. Rats were killed at 1, 2, 4, 6, 8, and 10 weeks postoperation, and serum testosterone, as well as testicular concentrations of the enzymes LDH & SDH, protein markers of testicular germinal cell development, were measured at the time of death. Although LDH and SDH concentrations decreased by 45 per cent in testes after simulated FSO at 4 weeks, control testes showed a 5 per cent increase in these enzymes. Serum testosterone decreased to one-fourth the initial value in rats after FSO, whereas control rats showed a slight increase. Within 2 weeks after simulated FSO, spermatocytes and sperm were sparse and there was marked disruption of tubular morphology; after 4 weeks interstitial fibrosis became prominent. Only a rare testis with good collateral vessels and resultant good histologic appearance and enzyme profile survived the FSO procedure, and these testes were considerably smaller than the controls.     

The influence of fat tissue on neuroma formation

The proximal stumps of transected sciatic nerves were implanted into an abdominal pedicle flap of fat tissue in rats. Nerve stumps that had been transected without implantation into fat tissue served as control experiments. At 4, 8, or 24 weeks postoperatively, the rats were sacrificed and the neuromas at the transected nerve ends together with the adjacent fat tissue were studied after intra-aortal perfusion fixation. Light microscopy revealed no significant difference in neuroma size between the two groups. In most animals with fat implantation, however, infiltration of fat tissue beyond the margins of the solid neuromatous bulb by regenerating nerve fibers was limited to rare axons growing along blood vessels and connective tissue strands. In only a few instances was the fat tissue itself invaded by minifascicles as was usually seen in the connective tissue surrounding control neuromas. It is concluded that diffuse outgrowth of nerve fibers is limited to some extent by fat tissue, which, however, is not an impermeable barrier for regenerating nerve fibers. Nevertheless, in a fat tissue flap, the neuroma is placed in a "soft pressure-free bed" which might be a prerequisite for permanent diminution of pain sensitivity.     

Orchidopexy or orchidectomy for preventing tissue hypoxia in contralateral testis following induction of ipsilateral abdominal testis associated with vas deferens obstruction

INTRODUCTION: An experimental study was planned to evaluate and compare the effects of orchidopexy and orchidectomy on ipsilateral and contralateral testes in rats subjected to ipsilateral abdominal testis and vas deferens obstruction. MATERIALS AND METHODS: Four groups of 12 rats each were established. Sham operation, intra-abdominal testis with vas deferens obstruction and orchidopexy or orchidectomy for prior intra-abdominal testis with vas deferens obstruction were performed in groups 1, 2, 3 and 4, respectively. While testes were maintained for 8 weeks in the same position in groups 1 and 2, orchidopexy or orchidectomy was performed in groups 3 and 4 after the first 4 weeks, and the remaining testes were harvested after an additional 4 weeks. Lactic acid hypoxanthine contents were determined and the groups were compared with the paired t test. RESULTS: Maintaining intra-abdominal testis with vas deferens obstruction for 8 weeks and orchidopexy yielded the highest lactate values. However lactate levels in contralateral testes did not increase. On the other hand, hypoxanthine levels revealed the highest values after the initial 4 weeks. The 8-week study period resulted in increases of ipsilateral and contralateral testicular hypoxanthine levels. Orchidopexy caused a decrease in ipsilateral testicular values and ameliorated the increase in hypoxanthine levels in contralateral testes. CONCLUSIONS: Replacing an intra-abdominal testis with its vas deferens ligated into the scrotum ameliorates the oxidative stress in both ipsilateral and contralateral testes. Since orchidectomy does not result in better contralateral testicular values, orchidopexy should be preferred when treating an undescended testis with vasal obstruction.     

Induction of chemical castration in male rats by a new long-acting LHRH-antagonist

LHRH-antagonists might represent a useful new type of androgen deprivation to treat prostatic cancer. In this context adult intact male rats were treated subcutaneously with different concentrations of the new LHRH-antagonist antide either once (1, 3, 6, 10, 15 mg/kg) or on 5 consecutive days (5 x 3 mg/kg). The effect on serum concentration of LH and testosterone and the effect on the weights of testes, prostate, and seminal vesicles was investigated after different periods of time (24 hours, 1, 2, 3, 5, and 8 weeks). Histological evaluation of the testes was also performed. A clear dose-dependent inhibitory effect on the above-mentioned parameters was observed. The most effective treatment schedule was the single application of 15 mg/kg resulting in castration-like inhibition of prostate weights and marked inhibition of spermatogenesis within 2 weeks, which was maintained 8 weeks after the injection. Serum LH and serum testosterone concentrations were below the detection limit of the assay within 2 weeks and showed first signs of recovery after 8 weeks. Histologically, no signs indicative of irreversible effects (testes) were observed. To summarize, the LHRH-antagonist antide was found to have a profound long-lasting inhibitory but reversible effect on the reproductive system of adult intact male rats. These data emphasize the suitability of this type of compound for the treatment of prostatic cancer.     

Vascularization of Artificial Beds for Pancreatic Islet Transplantation in a Rat Model

An alternative prevascularized bed with a subcutaneously located entrance would substantially improve islet engraftment, requiring much less invasive surgery. Studies have described times necessary for the creation of an artificial pouch suitable for subsequent islet transplantation. Polymeric mesh shaped in rounded scaffolds were implanted both subcutaneously and into the major omentum of Brown Norway female rats (n = 7). The connective tissue together with vessels were embedded into scaffolds at 1 week without regard to site. In contrast to the major omentum, vessels within the subcutaneous connective tissue surrounding the devices started to decline in 2 weeks and almost disappeared 1 week later. Magnetic resonance imaging (MRI) detected changes in fibrous tissue surrounding the wall, but only large veins located beside the devices were visible using basic MRI. The blood supply to the internal surface of the created beds was important for islet engraftment, but information could be obtained only by using dynamic contrast-enhanced MRI.     

Value of autologous chondrocyte transplantation in experimental cartilage defects reconstruction. Part III--Microscopic analysis of reconstructed cartilage thickness and integration with surrounding tissue]

Lack of cartilage vascularization is the reason of its low regenerative potential. The aim of this part of the study was microscopic evaluation of repair tissue thickness and its integration with surrounding cartilage, after autologous chondrocyte transplantation. MATERIAL AND METHODS: Repair of partial thickness cartilage defect (ICRS III(o) grade) on distal femur joint surface was evaluated (25 adolescent rabbits). Procedures were performed in two groups: I--autologous chondrocyte transplantation under periosteal flap, II--periosteal graft. Chondrocytes were isolated from the cartilage specimens by enzymatic digestion and cultured in vitro. The follow-up periods were established at 4, 8, 12 weeks. Repair tissue was evaluated microscopically according to modified O'Driscoll scale. RESULTS: In group I, 8 weeks after the procedure most of defects were filled with the newly formed tissue almost completely. Regenerate thickness after 4 and 12 weeks usually exceeded 1/2 of surrounding cartilage. In group II, 8 weeks after the procedure regenerate thickness amounted to at least 1/2 of surrounding cartilage, but 4- and 12-week observation revealed the decreased repair tissue thickness. In group I, 4 weeks after the procedure regenerative tissue was well integrated with surrounding cartilage, and this trait still gradually increased with time. In group II, there was partial integration or no integration of repair tissue with surrounding cartilage. CONCLUSION: Obtained results indicate, that tissue formed after autologous chondrocyte transplantation with use of periosteal flap was better in its thickness and integration with surrounding cartilage, as compared to tissue formed after use of periosteum alone. Autologous chondrocyte transplantation can not guarantee complete filling of the cartilage defect with the graft tissue and full integration with surrounding cartilage, without three-dimensional scaffold application.     

Effects of spermatic vascular division for correction of the high undescended testis on testicular function

Orchiopexy with division of the spermatic artery and veins is a commonly used technique for correcting the high undescended testis, although the longterm results have not been clearly defined. The left spermatic artery and veins of 22 adult Wistar albino rats were divided while preserving the vessels associated with the vas and cremaster muscle (DT). A sham operation was performed on the left testicle of six additional rats (ST). At 3 weeks postoperatively, both testes from all rats were removed. All testes were viable and bled when incised, although bleeding was considerably reduced in testes with DT. Mean testicular weights after DT were 1,061 +/- 423 mg compared with 1,634 +/- 125 mg for ST rats (p less than 0.02) and 1,508 +/- 119 mg for contralateral testes. The mean tubular diameter after DT was 220 +/- 37 mu compared with 303.1 +/- 10.7 mu for ST testes (p less than 0.02). The testicular biopsy score based upon the morphology of the spermatic tubules was 4.46 +/- 3.32 for DT testes and 8.65 +/- 0.23 for ST testes (p less than 0.02) compared with 8.38 +/- 0.18 for contralateral testes and an absolute normal value of 10. No morphologic abnormalities were observed in the contralateral unoperated testes from any of the rats. The contralateral testes in 12 additional rats were removed before DT. The mean testosterone values in these rats with one testicle was 1.43 +/- 0.75 ng/mL. Three weeks after DT, testosterone values were 0.19 +/- 0.31 ng/mL (p less than 0.01). It is concluded that division of the main spermatic artery and vein in rats produces testicular atrophy with spermatogenic arrest and interstitial cell dysfunction. Although collateral blood flow to the testis may be demonstrated, tissue perfusion is inadequate for normal spermatogenesis and endocrine function.     

Regulation of testicular ornithine decarboxylase in vitro. Effect of age, follicle-stimulating hormone, and luteinizing hormone

We have examined hormonal regulation of ornithine decarboxylase (ODC) activity in decapsulated rat testis, isolated testicular interstitial cells, and purified Leydig cells under defined conditions in vitro. Both immature (15 to 26 days old) and adult (60 to 90 days old) rat testes were employed. Basal (fresh tissue) ODC activity varied widely among rats of the same age but was similar (less than 5% difference) in pairs of testes from the same animal. For this reason, pairs of testes were compared in subsequent in vitro studies. ODC activity of decapsulated testes of adult rats declined (to 25 to 30% of basal) during 4 hours of incubation in Medium 199 + 0.1% bovine serum albumin + 0.1 mM 3-isobutyl-1-methylxanthine at 34 C. The addition of FSH, LH, prolactin, prostaglandin E2, epidermal growth factor, insulin, or 10% fetal calf serum singly or in combination failed to prevent this decline in ODC activity. In contrast, ODC activity of decapsulated testes of immature rats remained stable (versus fresh tissue) during 4 hours of incubation. The addition of FSH (100 ng/ml) caused a small but statistically significant (P less than 0.005) stimulation of the enzyme activity, and 8-bromo cyclic AMP (0.5 mM) mimicked the effect of FSH. In isolated interstitial cells from adult rats, LH stimulated ODC activity in a dose- (10 pg-200 ng/ml) and time-dependent fashion. 8-Bromo cyclic AMP mimicked the effect of LH. Prolactin, FSH, estradiol, insulin, prostaglandin E2, and epidermal growth factor did not alter the enzyme activity. LH also stimulated ODC activity of purified Leydig cells. This study demonstrates for the first time direct in vitro stimulation of rodent testicular ODC activity by gonadotropins and reveals marked age-dependent differences in regulation of this enzyme in vitro.     

入肝门静脉动脉化对大鼠肝脏损害的初步研究

目的：初步研究入肝门静脉完全动脉化加门腔分流术对大鼠肝脏的损害程度。方法100只肝硬化造模大鼠随机分为A组（n=40）,入肝门静脉完全动脉化（PVA）＋门腔分流（PCS）;B组（n=40）,仅行门腔完全分流;C组（n=20）,门静脉阻断30 min＋右肾切除。分别将各组大鼠术前和术后1、2、4、8周的肝组织切片行肝细胞诱导型一氧化氮合成酶（iNOS）免疫组织化学染色,然后进行图像分析。各取8只正常大鼠,分别于PVA术前及术后4、8周行肝组织切片,马松染色后分析正常大鼠PVA手术前后肝脏纤维增生情况。结果（1）A组2只（5%）大鼠肝脏切片中常规HE染色可见汇管区明显扩张,小叶间静脉内径显著扩张,静脉壁增厚明显,壁内可见红染的纤维增生。（2）大鼠刚完成肝硬化造模时,肝细胞胞质的iNOS表达至峰值,3组平均IOD达600583±32828;3组大鼠术后均较术前有明显下降,差异有统计学意义（P＜0.01）;术后4周内, A组仍明显高于B、C两组,差异有统计学意义（P＜0.01）;至术后8周时,3组iNOS表达差异无统计学意义。（3）正常大鼠肝间质胶原纤维染色在术前及术后4、8周的总累积光密度值差异无统计学意义。结论术后8周内,PVA不会导致正常大鼠肝间质纤维化增加,可使部分肝硬化大鼠汇管区及小叶间静脉壁纤维化;PVA对肝细胞的损害主要集中在术后4周内,待肝脏对新的血流动力学改变及其相应的影响达到稳态后,PVA对肝脏的损害则不明显。     

The time-response and magnitude of HCG-induced vascular changes are different in scrotal and abdominal testes

Adult unilaterally cryptorchid rats were injected with 50 IU human chorionic gonadotrophin (hCG). At 4, 8, 24 and 72 h after treatment, testicular vascular permeability was studied by injecting colloidal carbon intravenously. The number of blood vessel profiles labelled with carbon was increased by hCG in both types of testes, but the response was more sustained in abdominal than in scrotal testes. The number of polymorphonuclear leucocytes (PMNs) accumulating in testicular blood vessels and migrating into the interstitial space in response to hCG treatment was also measured. The volume density of intravascular and interstitial PMNs was increased in both types of testes but the peak response was larger in scrotal than in abdominal testes. PMN accumulation and vascular leakage were apparently correlated in the scrotal but not in the abdominal testes.
Testicular interstitial fluid (IF) was collected from intact and unilaterally cryptorchid adult rats. The IF was diluted with sterile buffer and injected intracutaneously in test animals. The vascular permeability response was assessed by measuring the leakage of Evans blue into the injection sites. IF from scrotal and abdominal testes increased vascular permeability in the skin. The response was rapid and transient. IF collected from rats given hCG 24 h earlier did not increase vascular permeability. The vascular permeability response to IF was reduced slightly in neutrophil-depleted animals. The inflammation mediator present in IF cannot explain the kinetics and magnitude of the hCG-induced changes in vascular premeability in intact or unilaterally cryptorchid rats.     

钻孔复合人工骨体内植入成骨的实验研究

目的探索符合临床需要的复合人工骨移植材料。方法以磷酸三钙＋多孔羟基磷灰石 (TCP＋ HA)为载体 ,分为钻孔、未钻孔及空白对照三组。自成年新西兰兔股骨转子部取得骨髓基质细胞进行传代培养,所得骨髓基质细胞再与钙磷陶瓷载体复合培养制成复合人工骨。然后植入兔背部肌肉内,分别于手术后第 2、 4、 8、 12周取材。利用组织学和电子显微镜等方法观察细胞在载体内的生长、复合人工骨植入肌肉内的成骨等情况,以及载体钻孔对细胞长入和成骨的影响。结果电子显微镜观察显示,传代的骨髓基质细胞与载体共同培养生长良好,并可长入钻孔载体内部。大体标本可见,复合人工骨植入后,人工骨与周围肌肉连接,无包膜形成。组织学观察显示,术后第 2周组织和血管长入;术后第 4～ 8周有少量骨形成;术后第 12周板层骨形成。三组均无淋巴细胞浸润。与未钻孔者比较,钻孔人工骨的细胞、组织和血管向中心部位生长速度快,中心部位成骨多且更均匀。结论磷酸三钙＋多孔羟基磷灰石载体具有良好的生物相容性及骨传导性;骨髓基质细胞具有成骨能力;载体钻孔有利于增加新骨形成的速度和数量,使成骨更为均匀。     

单次高能震波冲击对大鼠睾丸的影响

用ＪＤＰＮ－ＩＶ型体外震波碎石机直接冲击Ｗｉｓｔａｒ大鼠的睾丸，观察高能震波对雄性动物的生殖毒性作用。结果发现，单次高能震波冲击Ｗｉｓｔａｒ大鼠睾丸３周内，睾丸组织出现炎性损伤性改变，包括毛细血管充血及瘀血（５８％）、局部出血（４２％）、精母细胞线粒体浊肿、嵴减少或消失（４２％），粗面内质网颗粒减少或脱颗粒（３３％）。但是，受高能震波冲击睾丸的雄性Ｗｉｓｔａｒ大鼠与同龄母鼠配对同笼饲养后，其配对母鼠的受孕率、平均胚胎数、平均胎重与对照组比较无显著性差异，血清睾酮、孕酮及卵泡刺激素水平也无显著性改变。本研究结果表明，单次高能震波冲击大鼠睾丸会造成睾丸组织的炎性损伤性改变，但并不造成雄鼠生育能力的明显下降。     

Chemical sympathectomy by 6-OH dopamine during fetal life results in inguinal testis through altering cremasteric contractility in rats

Background/Purpose:

Androgens are proposed to influence testicular descent through modulating sympathetic tone. An experimental study was undertaken to evaluate the effects of prenatal chemical sympathectomy on testicular location associated with the alterations in contractile properties of cremaster muscles in rats.

Methods:

Time-mated pregnancies were started in 10 rats. Two groups, each receiving saline or 6-hydroxydopamine from day 15 to day 19 of intrauterine life were established. At 2 months of age, localization of testes were evaluated, cremaster muscles were removed, and contractile properties were studied. Twitch and tetanic contractions were recorded isometrically at 37°C. Effects of verapamil, isoprenaline, and L-NNA were investigated. Results were compared through analysis of variance (ANOVA), and P values less than .05 were considered to be significant.

Results:

Both testes of all male offspring in the control group (n = 19) were in the scrotum. Six offspring among 17 subjected to 6-hydroxydopamine had undescended testes. Treatment with 6-hydroxydopamine had no effect on force-frequency relationship of cremaster muscle strips. Cremaster muscles of rats exposed to 6-hydroxydopamine had lower sensitivity to voltage-sensitive Ca⁺⁺ channel blockade by verapamil (3 × 10⁴ mol/L; P < .05). These muscles displayed greater contractile response to isoprenaline (10⁻⁵ mol/L; P < .05) but not to nitric oxide synthase inhibition by N^ω-nitro-l-arginine. Alterations in contractile properties of the muscles did not differ according to localization of testes among rats subjected to 6-hydroxydopamine.

Conclusions:

Administration of 6-hydroxydopamine resulted in suprascrotally located testes. This localization has been associated with less exposure at sympathetic tonus. These findings support that sympathetic activity plays an important role in localization of testis.     

吸烟对雄性大鼠性功能影响的实验研究

目的 :研究吸烟对雄性大鼠性功能影响状况。　方法 :用人工呼吸器造成大鼠被动吸烟 ,测定大鼠尿、血、睾丸组织镉 (Cd)含量 ,T、LH值及观察酶组织化学 β SHDH变化 ,睾丸病理改变 ,阴茎海绵体变化。 　结果 :实验组血、尿、睾丸Cd值高于正常对照组 ,而T、LH值和 β SHDH酶低于正常对照组。实验组睾丸组织水肿、瘀血、炎性改变 ,电镜观察到阴茎海绵体血管壁增厚。　结论 :吸烟引起大鼠性功能降低。     

维生素E和氨基胍在糖尿病肾病治疗中的协同作用

目的探讨维生素E和氨基胍在糖尿病肾病（DN）治疗中的协同作用。方法①以一次性腹腔注射链脲佐菌素（STZ，55mg／kg）诱导糖尿病大鼠模型，将大鼠分为正常对照组、糖尿病对照组、糖尿病加维生素E治疗组、糖尿病加氨基胍治疗组、糖尿病加维生素E加氨基胍治疗组；②观察1、2、4、8、12、16周时各组大鼠24h尿白蛋白排泄率（UAER），16周时各组大鼠尿素氮（BUN）、血肌酐（SCr）及肾组织病理改变情况；③观察各组大鼠16周时肾小球活性氧（ROS）聚集情况以及肾间质8-羟基脱氧鸟苷（8-OHDG）表达情况。结果与糖尿病组比较，维生素E治疗组在2周时UAER明显下降，但在4、8、12、16周时两组比较无统计学意义；氨基胍治疗组和两药合用组则在包括2周以后的各时间点UAER均较糖尿病组明显下降，且两药合用组UAER下降更明显。16周时各组间BUN、SCr差异无统计学意义。16周时糖尿病组大鼠肾小球系膜区增宽，系膜基质聚集；维生素E治疗组肾组织病理无改善，氨基胍治疗组略有改善，而两药合用组则有明显改善。16周时糖尿病组大鼠肾小球ROS聚集，肾间质8-OHDG表达增强，维生素E组肾组织ROS聚集和8-OHDG表达未减轻，氨基胍治疗有一定程度减轻，两药合用组肾组织ROS聚集和8-OHDG表达则明显减轻。结论维生素E和氨基胍在DN的治疗中具有协同作用，而这一协同作用可能通过协同抗氧化来实现。     

Revascularization of the testis using a vascular induction technique: a potential approach for staged orchiopexy in high-undescended testis

The present study was designed to determine whether a fasciovascular flap as a vascular carrier could be used to revascularize the undescended testis for avoiding the hazardous effects of the Fowler-Stephens procedure, high division of the spermatic vessels, and for bringing high-undescended testes into the scrotum. A total of 25 Wistar rats were divided into five groups of five rats each. In each group, surgical procedures were performed bilaterally, i.e. ten testes in each group, as follows: sham-operated controls (group 1), undescended testes (group 2), high division of the spermatic vessels (group 3), vascular induction with immediate division of spermatic vessels (group 4), and with delayed division of spermatic vessels (group 5). Evaluations were done by measuring the testicular weight and volume, testicular blood flow, and testicular biopsy scores and by microangiography. A moderate to severe decrease in testicular weight and volume in all experimental groups was observed compared with the sham-operated controls (group 1), but this was significantly less in groups 2 and 5. High division of the spermatic vessels in groups 3 and 4 resulted in a significantly greater decrease in the testicular blood flow, but this did not occur in group 5. Microangiographically, an impaired vascular supply from the deferential artery in group 3 and insufficient revascularization from the fasciovascular carrier in group 4 were observed. However, efficient revascularization stemming from the superficial epigastric artery of the fasciovascular flap was found in group 5. The testicular biopsy scores of groups 2 and 5 were significantly greater than those of groups 3 and 4. The results of the present study demonstrate that the fasciovascular flap as a vascular carrier revascularizes the testis through spermatic vessels after delayed division and provides an adjuvant treatment modality or first-stage procedure in a salvage operation for high-undescended testis during staged orchiopexy.Presented at the 10th Japan Society of Plastic and Reconstructive Surgery Research Council Meeting, October 18–19, 2001, Tokyo, Japan.     

碱性成纤维细胞生长因子复合部分脱蛋白骨增强兔股骨头骨缺损修复作用的研究

目的　探讨碱性成纤维细胞生长因子 (basic fibroblast growth factor,b FGF)复合部分脱蛋白骨(partially deproteinised bone,PDPB)对股骨头骨缺损的修复作用。　方法　成年健康新西兰白兔 2 4只 4 8髋 ,随机分为3组 (n=16 ) ,切开关节囊 ,在头颈交界处开窗 ,制备骨缺损模型。 A组植入 b FGF/ PDPB,B组植入 PDPB,C组为空白对照 ,于术后 2、4和 8周分别处死动物 ,制备血管墨汁灌注标本 ,样本行 X线、组织学观察和图像分析。　结果　组织学观察 A组于术后 8周股骨头骨缺损完全修复 ,B组 8周时修复区移植材料未被完全爬行替代 ,C组仍有缺损残存。墨汁灌注显示 ,术后 2周时 A组修复区新生血管丰富 ,8周时与 B组无明显差异 ,C组各时相点血管稀少。术后 8周 X线片评价 ,A组 3侧优 ,2侧良 ,1侧可 ,优良率 80 % ;B组 1侧优 ,2侧良 ,2侧可 ,1侧差 ,优良率 5 0 % ;C组 1侧可 ,5侧差。术后 8周修复组织骨小梁体积分数 A组优于 B组 ,具有统计学意义 (P<0 .0 5 ) ,A和 B组都优于 C组 (P<0 .0 5 )。　结论　b FGF与 PDPB复合有效促进了兔股骨头骨缺损的修复。     

Erb:YAG and Hol:YAG Laser Osteotomy: The Effect of Laser Ablation on Bone Healing

Sixty-nine male Sprague Dawley rats were divided into three groups of 23 animals each and osteotomies were performed in group 1 with a power saw, in group 2 with the Erb:Yag laser, and in group 3 with the Hol:YAG laser. Two animals of each group were sacrificed 1 week, 4, 8, and 12 weeks after operation for histologic investigation, and five animals of each group at 4, 8, and 12 weeks after osteotomy for torque testing. Anterior-posterior (AP) radiographs were taken at the same time points and investigated for callus formation and development of pseudoarthrosis. All tibiae osteotomied with the Ho1:YAG laser (group 3) developed pseudoarthrosis within 12 weeks and, therefore, torque testing could not be performed for this group. Biomechanical measurements of bone treated by power saw or Erb:YAG laser osteotomies, respectively, showed no significant statistical difference in the stability of bone between the two groups. Histologic examination after 1 week exhibited fibrous tissue at the site of osteotomy in rats of all three groups and additionally carbonization in rats of group 3. Saw osteotomies resulted in more callus formation than Erb:YAG osteotomies, but both techniques provoked a certain reunion within 8 weeks. Hol:YAG laser-treated osteotomies, however, exhibited formation of dense fibrous tissue, carbonization and no callus formation within 12 weeks. Radiographic pictures showed more callus formation for saw osteotomies as compared to those performed with the Erb: YAG laser. For Hol:YAG laser osteotomies pseudoarthrosis was identified also radiologically. © 1994 WiIey-Liss, Inc.     

Effect of experimental microvascular orchidopexy on spermatogenic cell differentiation in the testes of the dog

Experimental microsurgical orchidopexy was undertaken in 15 healthy mongrel dogs by anastomosing the testicular artery and vein to the ipsilateral caudal epigastric vessels. At pre-selected post-operative intervals of 4 weeks, 5 or 8 months the results were morphologically and histologically evaluated by the 'testicular biopsy score count' method. This method is based on the presence of the main spermatogenic types arranged in order of maturity. Between the mean scores of the normal and the operated testes there was a significant difference. The differentiation of the spermatogenic epithelium of the reconnected testis is slightly hampered, but not seriously.