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1.
2.

Background

Research in biliary atresia has been hindered by lack of a suitable animal model. Lampreys are primitive vertebrates with distinct larval and adult life cycle stages. During metamorphosis the biliary system of the larval lamprey disappears. Lamprey metamorphosis has been proposed as a model for biliary atresia. We have begun to explore cellular events during lamprey metamorphosis by assessing for cholangiocyte apoptosis.

Materials and Methods

Sea lamprey larvae were housed under controlled environmental conditions. Premetamorphic larvae were induced to undergo metamorphosis by exposure to 0.01% KClO4. Animals were photographed weekly, and the stage of metamorphosis was assigned based upon external features. Livers were harvested and processed for routine histology and immunohistochemistry. DNA fragmentation was detected using deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assays and cholangiocytes were identified with antibodies to cytokeratin-19. Percent TUNEL+ cholangiocytes at different stages of metamorphosis was determined.

Results

The percentage of TUNEL+ cholangiocytes was 10% in premetamorphic (stage 0) lamprey (n = 6), 51% at stage 1 (n = 6), 40% at stage 2 (n = 5), 18% at stage 3 (n = 5), and 9% stage 4 (n = 4). Routine hemotoxylin and eosin stained paraffin-embedded tissue sections revealed frequent apoptotic bodies at stages 3 and 4 of metamorphosis without histologic evidence of necrosis.

Conclusions

DNA fragmentation is identified at the earliest stages of metamorphosis during induced metamorphosis in lampreys. Additional studies are necessary to validate this potentially valuable animal model.  相似文献   

3.

Objective

To investigate the effect on intrahepatic cholangiocytes mediated by hypoxic preconditioning (HP) after liver transplantation and the role of vascular endothelial growth factor (VEGF).

Materials and Methods

This experiment was based on a model of rat orthotopic liver autotransplantation. Sprague-Dawley rats were randomly divided into 3 groups: normal control, autotransplantation (AT), and HP. The HP group was subjected to 8% oxygen atmosphere for 90 minutes before surgery. At 6, 12, 24, and 48 hours after autotransplantation, the rats were killed for testing .Serum total bilirubin, direct bilirubin, and alkaline phosphatase concentrations were determined. The microstructure of cholangiocytes and the ultramicrostructure of cholangioles were determined. Immunohistochemistry was used to detect the expression of VEGF and the proliferation rate of cholangiocytes.

Results

Total bilirubin, direct bilirubin, and alkaline phosphatase concentrations in the AT group increased considerably more than in the HP group during the entire interval (P < .05). Light microscopy demonstrated that the microstructure of cholangiocytes in the AT group was damaged more seriously than in the HP group. At transmission electron microscopy, the ultramicrostructure of cholangioles was changed more obviously than in the HP group. The expression of VEGF on cholangiocytes and the proliferation rate of cholangiocytes were higher in the HP group than in the AT group over the entire experiment (P < .05).

Conclusion

Hypoxic preconditioning has a protective effect on cholangiocytes after liver autotransplantation. The mechanism may be related to HP-induced overexpression of VEGF on cholangiocytes.  相似文献   

4.

Introduction

Tumor necrosis factor (TNF)-α mediates inflammation and apoptosis in ischemia-reperfusion (IR) injury of the kidneys. Etanercept, a soluble TNF-α receptor, has shown anti-inflammatory and anti-apoptotic effects in several animal models of renal injury, including chronic insufficiency and unilateral ureteral obstruction. We evaluated the protective effect of etanercept against experimental renal IR injury.

Methods

Male Sprague-Dawley (SD) rats were divided into 4 groups: saline-treated sham rats, etanercept-treated sham rats, saline-treated IR rats, and etanercept-treated IR rats. Renal messenger RNA (mRNA) levels of TNF-α and monocyte chemotactic protein-1 (MCP-1) were measured by real-time polymerase chain reaction (PCR) at 24 hours after IR injury. The protein levels of renal Bcl-2 associated X (Bax), B-cell lymphoma 2 (Bcl), extracellular signal-regulated kinase (ERK), and caspase-3 activation were evaluated using Western blot analysis. The degree of apoptosis of renal tubular cells was determined using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays.

Results

At 24 hours after IR injury, the serum levels of blood urea nitrogen (BUN) and creatinine were significantly lower among etanercept-treated than saline-treated IR rats. Renal mRNA levels of TNF-α and MCP-1 in saline-treated IR rats were significantly higher than the levels in saline-treated sham rats, and TNF-α and MCP-1 mRNA levels in etanercept-treated IR rats were significantly lower than those in saline-treated IR rats. Etanercept pretreatment of IR-injured rats significantly increased EKR phosphorylation and reduced the renal Bcl-2/Bax ratio, the renal caspase-3 activation, and the number of TUNEL-positive apoptotic cells.

Conclusion

Etanercept improved resistance to renal injury during IR by enhancing the activation of ERK and increasing the Bcl-2/Bax ratio.  相似文献   

5.

Background and aims

Reduction of biliary serotonin N-acetyltransferase (AANAT) expression and melatonin administration/secretion in cholangiocytes increases biliary proliferation and the expression of SR, CFTR and Cl/HCO3 AE2. The balance between biliary proliferation/damage is regulated by several autocrine neuroendocrine factors including vascular endothelial growth factor-A/C (VEGF-A/C). VEGFs are secreted by several epithelia, where they modulate cell growth by autocrine and paracrine mechanisms. No data exists regarding the effect of AANAT modulation on the expressions of VEGFs by cholangiocytes.

Methods

In this study, we evaluated the effect of local modulation of biliary AANAT expression on the cholangiocytes synthesis of VEGF-A/C.

Results

The decrease in AANAT expression and subsequent lower melatonin secretion by cholangiocytes was associated with increased expression of VEGF-A/C. Overexpression of AANAT in cholangiocyte lines decreased the expression of VEGF-A/C.

Conclusions

Modulation of melatonin synthesis may affect the expression of VEGF-A/C by cholangiocytes and may modulate the hepatic microvascularization through the regulation of VEGF-A/C expression regulating biliary functions.  相似文献   

6.
Biliary atresia (BA) is a disease of the newborn that results in obstruction of the biliary tree. The cause of BA remains unknown; however, recent studies using the murine model of biliary atresia have found that rotavirus infection of the biliary epithelial cell (cholangiocyte) triggers an inflammatory response. We hypothesized that rotavirus infection of cholangiocytes results in the release of chemokines, important mediators of the host immune response.

Methods

In vivo, Balb/c pups were injected with rhesus rotavirus (RRV) or saline, and, their extrahepatic bile ducts were microdissected 2, 5, 7, and 14 days after injection. Next, an immortalized cholangiocyte cell line (mCl) was incubated with RRV or serum-free media. Qualitative and quantitative chemokine assessment was performed using enzyme-linked immunosorbent assay, polymerase chain reaction, and immunohistochemistry.

Results

In vivo, increased levels of the chemokines macrophage inflammatory protein 2, monocyte chemotactic protein 1, KC and Regulated upon Activation, Normal T Expressed and Secreted were found in RRV-infected murine bile ducts. In vitro, infected mCl cells produced increasing amounts of these same chemokines in relation to dose and time.

Conclusion

These novel results suggest that chemokine expression by RRV-infected cholangiocytes may trigger a host inflammatory process that causes bile duct obstruction. Understanding how viral infection initiates this response may shed light on the pathogenesis of biliary atresia.  相似文献   

7.
8.

Purpose

The objective of this study is to describe a prognostic classification for prenatally diagnosed sacrococcygeal teratoma (SCT).

Methods

Charts from 44 fetuses were reviewed. Three groups were defined as follows: group A—tumor diameter less than 10 cm, absent or mild vascularity and slow growth; group B—diameter 10 cm or greater, pronounced vascularity or high-output cardiac failure and fast growth; group C—diameter 10 cm or greater, predominantly cystic lesion with absent or mild vascularity and slow growth.

Results

Size at diagnosis, growth rate, and vascularity were higher in group B. Gestational age at delivery was lower in group B. Eleven of 21 died in the perinatal period in group B and none in groups A and C. In group C, drainage or shunting of the SCT has been performed in 6 of 10 cases.

Conclusions

Group A is associated to good maternal and perinatal outcome, as well as group C, although shunting or drainage of the SCT could be necessary. Large fast-growing SCT with rich vascularity is associated with a higher perinatal mortality and morbidity than smaller lesions with mild vascularity.  相似文献   

9.

Background/Purpose

Alternatives are still being sought in vascular surgery to address the problem of arrested growth after anastomosis in growing vessels, and opinions differ widely regarding the most suitable technique. This study compared vascular growth and permeability after anastomosis using the latest-generation vascular closure staple (VCS) system and the conventional suture technique to ascertain which approach yielded better results.

Methods

Thirty 55-day-old lambs underwent end-to-end anastomosis of the carotid artery and jugular vein. Serial ultrasonography and angiography were carried out over the ensuing 6-month growth period, after which lambs were euthanized.

Results

Both VCS clips and polypropylene suture allowed longitudinal and transverse vessel growth; however, longitudinal growth was significantly greater in clip-closed vessels than in either sutured or untreated vessels.

Conclusions

The results obtained for vascular growth and permeability suggest that VCS clips may provide a suitable alternative to conventional suture in pediatric vascular surgery.  相似文献   

10.

Background

Conventional techniques for hemostasis during thyroidectomy rely on knot tying, clips, and electrocoagulation. Recently, the Harmonic FOCUS Shear (Ethicon Endo-Surgery, Inc, Cincinnati, OH) was developed for thyroidectomy.

Methods

Between December 2007 and March 2008, 62 consecutive patients (45 women, 17 men; mean age 50.9 years) undergoing thyroidectomy were randomized into 2 groups: group A, where the FOCUS was used, and group B, where electrocoagulation and clamp-and-tie technique were used.

Results

The 2 groups were similar in terms of age, sex ratio, indication for surgery, and thyroid volume. Operative time was significantly shorter in group A. Significantly fewer clips and ties were used, and postoperative pain and suction balloon amount were also significantly lower in the FOCUS group. The only postoperative complication was a patient with transient hypocalcemia in group B.

Conclusions

FOCUS is a reliable and safe tool for thyroidectomy. Its utilization is associated with a shorter operative time, less blood loss, and less postoperative pain.  相似文献   

11.

Aims of Study

Retinoid-mediated signal transduction plays a crucial role in the embryogenesis of various organs. We previously reported the successful induction of anorectal malformations in mice using retinoic acid (RA). Retinoic acid controls the expression of essential target genes for cell differentiation, morphogenesis, and apoptosis through a complicated interaction in which RA receptors form heterodimers with retinoid X receptors. In the present study, we investigated whether the retinoid antagonist, LE135, could prevent the induction of anorectal malformations (ARMs) in mice.

Methods

Retinoic acid was intraperitoneally administered as 100 mg/kg of all-trans RA on E9; and then the retinoid antagonist, LE135, was intraperitoneally administered to pregnant ICR strain mice on the eighth gestational day (E8), 1 day before administration of RA (group B) or on E9, simultaneously (group C) with RA administration. All of the embryos were obtained from the uteri on E18. Frozen sections were evaluated for concentric layers around the endodermal epithelium by hematoxylin and eosin staining.

Results

In group A, all of the embryos demonstrated ARM with rectoprostatic urethral fistula, or rectocloacal fistula, and all of the embryos showed the absence of a tail. In group B, 36% of the embryos could be rescued from ARM. However, all of the rescued embryos had a short tail that was shorter than their hind limb. The ARM rescue rates in group B were significantly improved compared to those in group A (P < .01). In group C, 45% of the embryos were rescued from ARM, but all of the rescued embryos had short tail. The ARM rescue rate in group C was significantly improved compared to that in group A (P < .01). However, there was no significant difference in the ARM rescue rate between group B and Group C.

Conclusion

The present study provides evidence that in the hindgut region, RAR selective retinoid antagonist, LE135, could rescue embryos from ARM. However, the disturbance of all-trans RA acid was limited to the caudal region. Further study to establish an appropriate rescue program for ARM in a mouse model might suggest a step toward protection against human ARM in the future.  相似文献   

12.
目的:探讨不同时间点减压环扎法所致损伤脊髓中神经细胞凋亡及Bax、Bcl-2的表达及其意义。方法:成年SD大鼠84只,随机分为4组:A组,仅行椎板减压及硬脊膜囊周长测量;采用环扎法建立大鼠脊髓损伤模型,B组于环扎术后8h行脊髓减压;C组于环扎术后72h行脊髓减压;D组环扎术后不行脊髓减压。各组分别于术后1d、7d、14d、21d取材,所得脊髓标本行HE染色、Tunel染色及免疫组化法检测Bax、Bcl-2阳性细胞数等情况,并采用BBB评分评价大鼠后肢神经功能变化。结果:Bax染色:B组和C组术后1d开始阳性细胞数增加,7d时达高峰,14d时仍较明显,21d降低;D组术后阳性细胞数持续升高。Bcl-2染色:B组和C组术后阳性细胞数持续升高;D组术后1d阳性细胞数最多,之后持续降低。Tunel染色:B、C及D组术后1d开始出现凋亡细胞,7d时达高峰,以后逐渐减少,21d时仍可见。Bcl-2/Bax值与Tunel阳性细胞数关系:B组和C组二者存在负相关;D组二者呈正相关。BBB评分:A组术后1周后肢运动功能恢复正常;B组和C组术后逐渐升高(P<0.05);D组术后1天开始逐渐降低,7天时最低,然后逐渐升高。结论:环扎法可以建立稳定的大鼠脊髓损伤模型;早期减压能减少继发性脊髓损伤细胞凋亡,有利于神经功能恢复。  相似文献   

13.
14.

Purpose

Biliary atresia (BA) remains one of the most intractable liver diseases leading to liver fibrosis. Serum hepatocyte growth factor (HGF) has been shown to increase in cirrhotic patients. The aim of this study was to investigate the possible role of HGF in BA.

Methods

Serum levels of HGF were determined using an enzyme-linked immunosorbent assay from 28 BA patients and 25 healthy children. The patients were categorized into 3 groups according to their clinical outcomes (good, fair, and poor): group A (good), jaundice-free patients (total bilirubin [TB] < 2.0 mg%); group B (fair), patients with mild to moderate jaundice (TB, 2 to 10 mg%); and group C (poor), patients with marked jaundice (TB > 10 mg%). Unpaired t test and analysis of variance (ANOVA) with post-hoc tests were used. Data were expressed as mean and SEM.

Results

Serum HGF levels in BA patients were higher than the controls (P = .02). Subgroup analysis found that there were 12 patients in group A, 8 patients in group B, and 8 patients in group C. The mean age of patients in groups A, B, and C were 5.34 ± 0.52, 7.45 ± 1.98, and 5.49 ± 1.57 years (P > .05). Serum HGF in controls and groups A, B, and C were 0.24 ± 0.03, 0.28 ± 0.04, 0.36 ± 0.09, and 0.56 ± 0.07 ng/mL, respectively. Serum HGF levels in BA patients with poor outcome were higher than patients with good outcome (P = .02). There was no difference in serum HGF of BA patients with fair outcome compared with other groups.

Conclusions

Serum HGF is elevated in BA. Furthermore, BA patients with poor outcome have significantly elevated HGF compared with patients with good outcome. Serum HGF levels may be predictive of prognosis with respect to the progression of liver dysfunction. However, the results of HGF in patients with fair outcome are inconclusive, probably because of the small sample size. Further studies are needed to elucidate the detailed mechanisms.  相似文献   

15.
目的 探讨盐酸戊乙奎醚对大鼠创伤性急性肺损伤时细胞凋亡的影响.方法健康雄性SD大鼠54只,体重225~275kg,采用随机数字表法,将大鼠随机分为对照组(C组)、创伤性急性肺损伤组(ALI组)和盐酸戊乙奎醚组(P组),每组18只.采用自制胸部撞击器撞击大鼠胸壁的方法制备创伤性急性肺损伤模型.P组分别于撞击后即刻、撞击后12 h时腹腔注射盐酸戊乙奎醚2 mg/kg.分别于撞击后3、12、24 h时各组随机取6只大鼠处死取肺,光镜和电镜下观察肺组织病理学结果,TUNEL法测定凋亡细胞,计算凋亡指数,免疫组化法检测Bax和Bcl-2的表达.结果 与C组比较,ALI组和P组各时点肺组织细胞凋亡指数、Bax和Bcl-2的表达水平升高,Bcl-2/Bax比值降低(P<0.05);与ALI组比较,P组各时点肺组织细胞凋亡指数和Bax表达水平降低,Bcl-2的表达水平和Bcl-2/Bax比值升高(P<0.01).P组肺组织病理学损伤程度较ALI组减轻.结论 盐酸戊乙奎醚可通过抑制细胞凋亡减轻大鼠创伤性急性肺损伤.
Abstract:
Objective To investigate the effect of penehyclidine hydrochloride on the cell apoptosis in lung tissues in a rat model of traumatic acute lung injury (ALI) .Methods Fifty-four SD rats weighing 225-275 kg were randomly divided into 3 groups ( n = 18 each) : control group (group C) , ALI group, penehyclidine hydrochloride group ( group P) . Traumatic ALI was induced by dropping a self-made impact device on the chest of anesthetized rats according to the technique described by Raghavendran et al. Intraperitoneal penehyclidine hydrochloride 2 mg/kg was injected immediately after blunt chest trauma and at 12 h after blunt chest trauma in group P. Six rats in each group were sacrificed at 3, 12 and 24 h after blunt chest trauma and the lung tissues collected for microscopic examination and determination of cell apoptosis (by TUNEL) and expression of Bax and Bcl-2 (by immuno-histochemical staining) . The apoptosis index was calculated. Results The apoptosis index and expression of Bax and Bcl-2 were significantly higher, while the ratio of Bcl-2/Bax was significantly lower at each time point in groups ALI and P than in group C ( P < 0.05) . The apoptosis index and Bax expression were significantly lower,while the Bcl-2 expression and ratio of Bcl-2/ Bax higher at each time point in group P than in group ALI.The microscopic examination showed that penehyclidine hydrochloride injection significantly attenuated the pathologic changes. Conclusion Penehyclidine hydrochloride can reduce the traumatic ALI through inhibiting the cell apoptosis in rat lung tissues.  相似文献   

16.

Background

Adaptation after massive small bowel resection (SBR) is associated with increased rates of enterocyte proliferation (P) and apoptosis (A). In the present study, we sought to determine the effect of dual therapy designed to increase P and simultaneously reduce A.

Methods

C57Bl/6 mice underwent a 50% small bowel resection (SBR) or sham operation, and then received an inhibitor of apoptosis (pan-caspase inhibitor), a stimulus for proliferation (epidermal growth factor; EGF), a combination, or vehicle control. After 3 days, adaptive morphology (villus height, crypt depth) and rates of enterocyte turnover (proliferation and apoptosis) were measured in the remnant ileum.

Results

Adaptation in controls and treated with the inhibitor was similar. EGF-treated mice demonstrated an even greater adaptive response. Combined therapy with the inhibitor and EGF resulted in maximal adaptation as gauged by the greatest increases in villus height and crypt depth and ratio of rates of P to A.

Conclusion

The capacity for adaptation following massive SBR is maintained via tight regulation of cell production and death. Pharmacologic intervention directed at increasing enterocyte proliferation while simultaneously decreasing apoptosis augments adaptation greater than either intervention alone and may provide a useful strategy to clinically amplify adaptation.  相似文献   

17.

Background

Despite morphologic differences of lymphocytes aggregation between nonrejection (0 on the International Society for Heart and Lung Transplantation [ISHLT] scale) and moderate focal cellular rejection (1a, ISHLT), genetic and clinical differences have not been shown in Cardiac Allograft Rejection Gene Observation (CARGO) studies. Therefore, we sought to compare the expression of selected antigens associated with apoptosis in heart transplant recipients in the context of grade 0 versus grade 1a cellular rejection episodes. We assessed the expression of annexin V, a nonspecific apoptosis marker, Bcl-2 as opposed to antiapoptotic activity of Bcl-xL and Bcl-xL/S.

Materials and Methods

We retrospectively examined 17 heart transplant patients (2 women and 15 men) of overall mean age of 46.2 ± 13.9 years and body mass index of 25.7 ± 3.2. Ten biopsies showed rejection grade 0 and the other 10, grade 1a on the ISHLT scale, comprising groups A and B, respectively. Endomyocardial biopsy specimens were processed using routine immunohistochemical methods. The expression of apoptotic molecules was assessed according to the IHC method: 0, the lack of expression; 1, trace; 2, distinct; and 3, strong. A correlation was analyzed between particular molecular expressions.

Results

We observed a significant increase in Bcl-2 expression associated with rejection. The expression of other antigens did not show a significant tendency. No correlation was noted among group A, whereas in group B those were significant strong and negative correlations with Bcl-2 and Bcl-xL/S.

Conclusion

Bcl-2 expression corresponded to the morphologic progression of graft rejection as opposed to Bcl-xL/S activity.  相似文献   

18.

Purpose

This study aimed to determine the effect of melatonin in preventing ischemia-reperfusion (I-R) injury-induced tissue damage and on spermatogenesis after experimental testicular torsion (TT).

Methods

Forty peripubertal rats were divided into 4 groups each containing 10 rats: control (C), sham (S), torsion plus detorsion (TD), and torsion plus melatonin (M). The left testes were rotated 720° for 6 hours and detorsed for 6 hours thereafter. Serum inhibin B (IB) levels were measured in blood samples taken from all groups. Left orchiectomies were performed to determine the tissue levels of Johnsen's scores (JS) and malondialdehyde (MDA).

Results

Serum IB levels in the S and TD groups were significantly lower compared with that in the C group, whereas they were higher in the M group compared with the TD group. The MDA levels were significantly lower in the C, S, and, M groups compared with the TD group. Johnsen's scores were significantly higher in the C, S, and M groups compared with the TD group.

Conclusions

Our results suggested that melatonin is a potent antioxidant agent in preventing testicular I-R injury, as shown by increased IB levels and JS.  相似文献   

19.

Purpose

Fundoplication is frequently required for gastroesophageal reflux (GER)-related respiratory disease. Correlation between esophageal pH data and respiratory symptoms is poor but may be improved by monitoring hypopharyngeal pH. Reflux to the hypopharynx is underestimated by salivary bicarbonate. The aim of this study was to determine if hypopharyngeal pH monitoring using pH 4 and pH 5 as reflux thresholds could predict children with reflux-related respiratory disease.

Methods

One hundred five children aged 4 months to 12 years underwent esophageal and hypopharyngeal pH monitoring. Hypopharyngeal pH data were analyzed using pH 4 and pH 5 as reflux thresholds. pH data from 4 groups were compared: group A, control group, no GER, no respiratory symptoms (n = 20); group B, respiratory symptoms, no GER (n = 16); group C, GER, no respiratory symptoms (n = 26); and group D, both GER and respiratory symptoms (n = 37).

Results

Comparing groups C and D, there was no significant difference in hypopharyngeal pH data. Using pH 5 as the reflux threshold, children in group B refluxed to the hypopharynx significantly more frequently than controls. This was most evident in children with wheeze.

Conclusion

Hypopharyngeal pH monitoring does not differentiate children with GER and respiratory symptoms from those with GER alone and is therefore of doubtful value in diagnosing recurrent aspiration.  相似文献   

20.
目的 探讨自体骨髓单核细胞移植对血管新生及胆道缺血病变的影响.方法 将30只日本大耳白兔随机分为3组:假手术组(A组)、实验模型组(B组)和骨髓单核细胞移植组(C组),每组10只.3组均游离胆总管、肝总动脉及其间的疏松结缔组织,B组和C组阻断胆总管远端及肝总动脉2 h,C组经肝总动脉注射PKH26标记的自体骨髓单核细胞.术后监测生化指标的变化情况.术后4周开腹行胆道造影.同时,取第一肝门处汇管区肝组织制作石蜡切片,应用免疫组织化学方法观察自体骨髓单核细胞在肝内缺血环境中的分布及分化情况,并检测微血管密度.结果 术后C组生化指标恢复明显优于B组,骨髓单核细胞可分化成血管内皮细胞.术后4周,C组胆道破坏较B组轻,且胆道周围新生毛细血管多于B组.结论 自体骨髓单核细胞移植可以促进局部缺血组织毛细血管的增生,改善局部缺血胆道组织的微循环,从而减轻缺血型胆道病变的程度,甚至预防缺血型胆道病变的发生.  相似文献   

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