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91.
脊髓全横断大鼠神经生长因子和脑源性神经营养因子表达及三七皂苷的干预效应 总被引:1,自引:0,他引:1
目的:神经生长因子和脑源性神经营养因子同属神经营养素家族,在神经系统发育及维持正常神经元功能中有重要作用。实验拟证实脊髓全横断损伤三七皂苷对大鼠神经生长因子及脑源性神经营养因子蛋白水平的表达变化产生了影响。方法:实验于2005-06/09在昆明医学院神经科学研究所完成。①实验材料:清洁级健康雌性SD大鼠72只,质量(200±20)g;三七皂苷由云南植物药业提供。②分组及实验过程:大鼠被随机分为4组:假手术组、单纯脊髓全横断损伤组、脊髓全横断损伤 生理盐水(0.5mL/次)组、脊髓全横断损伤 三七皂苷(100mg/kg/次)组,每组18只。于T10水平横断大鼠脊髓,假手术组仅剪开硬脊膜而不损伤脊髓。后2组于术后30min,4,24,48,72h腹腔注射给药各1次。③实验评估:各组于术后3,7及21d分别取6只大鼠L1~2段脊髓制作冰冻切片,采用免疫组织化学ABC法染色。观察并计数脊髓腹角神经生长因子、脑源性神经营养因子蛋白的表达变化;常规苏木精伊红染色观察脊髓的组织病理变化。结果:72只大鼠全部进入结果分析:①脊髓全横断损伤后脊髓出现明显的神经变性坏死、炎性浸润等病理变化,三七皂苷可减轻这些变化。②神经生长因子蛋白主要分布于灰质神经元胞浆及胶质细胞胞核中。在正常脊髓有少量表达,脊髓损伤后7d表达明显升高,直到伤后21d仍高于假手术组(P<0.05);三七皂苷可明显促进其表达,伤后3,7d均明显高于其他各组(P<0.05),在21d时下降但仍高于假手术组(P<0.05)。③脑源性神经营养因子蛋白主要分布于腹角的运动神经元胞浆中,胶质细胞未见着色。在正常脊髓有少量表达,脊髓损伤后7d表达明显升高(P<0.05),伤后21d已下降,同假手术组相比差异无显著性(P>0.05);三七皂苷可明显促进其表达,伤后3,7,21d均明显高于所有对照组(P<0.05)。结论:三七皂苷可减轻脊髓横断性损伤后继发损害,增加神经生长因子、脑源性神经营养因子表达量及提前神经生长因子、脑源性神经营养因子表达时间,提示其可以促进脊髓损伤早期修复。 相似文献
92.
93.
Kelvin KF Tsoi Heyson CH Chan Philip WY Chiu Carol YY Pau James YW Lau Joseph J Y Sung 《Journal of gastroenterology and hepatology》2010,25(1):8-13
Background and Aims: In the management of peptic ulcer bleeding, the benefits of second‐look endoscopic treatment with thermal coagulation or injections in controlling recurrent bleeding is unsure. This study set out to compare efficacy of routine second‐look endoscopy with treatment using either thermal coagulation or injections versus single endoscopy by pooling data from published work. Methods: Full publications in the English‐language published work as well as abstracts in major international conferences were searched over the past 10 years, and six trials fulfilling the search criteria were found. Outcome measurements included: (i) recurrent bleeding; (ii) requirement of surgical intervention; and (iii) mortality. We examined heterogeneity of trials and pooled the effects by meta‐analysis. The quality of studies was graded according to the prospective randomization, methods of patient allocation, the list of exclusion criteria, outcome definitions and the predefined salvage procedures for uncontrolled bleeding. Results: Among 998 patients recruited in these five randomized trials, 119 received routine second‐look endoscopy with thermal coagulation, and 374 received second‐look with endoscopic injection and 505 had single endoscopic therapy. Less recurrent bleeding was reported after thermal coagulation (4.2%) than single endoscopy (15.7%) (relative risk [RR] = 0.29; 95% confidence interval [CI] = 0.11–0.73), but no reduction was reported for the requirement of surgical intervention and all‐cause mortality. Injection therapy did not reduce re‐bleeding (17.6%) when compared to single endoscopy (20.8%; RR = 0.85; 95% CI = 0.63–1.14), requirement for surgery and mortality. Conclusion: Routine second‐look endoscopy with thermal coagulation, but not injection therapy, reduced recurrent peptic ulcer bleeding. There is no proven benefit in reducing surgical intervention and overall mortality. 相似文献
94.
Bensinger WI; Weaver CH; Appelbaum FR; Rowley S; Demirer T; Sanders J; Storb R; Buckner CD 《Blood》1995,85(6):1655-1658
Peripheral blood stem cells (PBSCs) are widely used in autologous transplantation because of ease of collection and rapid hematopoietic reconstitution. However, PBSCs have rarely been used for allogeneic transplantation because of concerns about donor toxicities from cytokine administration and the theoretical increased risk of graft- versus-host-disease (GVHD) from the large number of T cells infused. Eight patients with advanced malignancies received allogeneic PBSC transplants from genotypically HLA-identical sibling donors. All donors received 5 days of recombinant human granulocyte colony-stimulating factor (rhG-CSF; 16 micrograms/kg/day) subcutaneously and were leukapheresed for 2 days. After treatment of the patient with total body irradiation and cyclophosphamide (n = 7) or etoposide, thiotepa, and cyclophosphamide (n = 1), PBSCs were infused immediately after collection and without modification. All patients received cyclosporine and either methotrexate (n = 6) or prednisone (n = 2) for GVHD prophylaxis, rhG-CSF was well tolerated with mild bone pain requiring acetaminophen occurring in two donors. All patients engrafted and in seven hematopoietic recovery was rapid, with 500 neutrophils/microL achieved by day 18 and 20,000 platelets/microL by day 12. Complete donor engraftment was documented by Y chromosome analysis in all four sex-mismatched donor-recipient pairs tested and by DNA analysis in two sex-matched pairs. One patient died on day 18 of veno-occlusive disease of the liver with engraftment but before chromosome analysis could be performed (results are pending in 1 patient). A second patient died of fungal infection 78 days after transplant. Grade 2 acute GVHD occurred in two patients and grade 3 GVHD occurred in one patient. One patient is 301 days from transplant in remission with chronic GVHD; the remaining five patients are alive and disease free 67 to 112 days after transplantation. Preliminary results indicate that allogeneic PBSCs mobilized by rhG-CSF can provide rapid hematologic recovery without an appreciably greater incidence of acute GVHD than would be expected with marrow. Further follow-up is required to determine the incidence of chronic GVHD and any potential beneficial effects on relapse after transplant. 相似文献
95.
Stem cell factor retards differentiation of normal human erythroid progenitor cells while stimulating proliferation 总被引:5,自引:12,他引:5
Stem cell factor (SCF), the ligand for the c-kit tyrosine kinase receptor, markedly stimulates the accumulation of erythroid progenitor cells in vitro. We now report that SCF delays erythroid differentiation among the progeny of individual erythroid progenitors while greatly increasing the proliferation of these progeny. These effects appear to be independent of an effect on maintenance of cell viability. Highly purified day-6 erythroid colony-forming cells (ECFC), consisting mainly of colony-forming units-erythroid (CFU-E), were generated from human peripheral blood burst-forming units-erythroid (BFU-E). Addition of SCF to the ECFC in serum-free liquid culture, together with erythropoietin (EP) and insulin-like growth factor 1 (IGF-1), resulted in a marked increase in DNA synthesis, associated with a delayed peak in cellular benzidine positivity and a delayed incorporation of 59Fe into hemoglobin compared with cultures without SCF. In the presence of SCF, the number of ECFC was greatly expanded during this culture period, and total production of benzidine-positive cells plus hemoglobin synthesis were ultimately increased. To determine the effect of SCF on individual ECFC, single-cell cultures were performed in both semisolid and liquid media. These cultures demonstrated that SCF, in the presence of EP and IGF-1, acted on single cells and their descendants to delay erythroid differentiation while substantially stimulating cellular proliferation, without an enhancement of viability of the initial cells. This was also evident when the effect of SCF was determined using clones of ECFC derived from single BFU-E. Our experiments demonstrate that SCF acts on individual day-6 ECFC to retard erythroid differentiation while simultaneously providing enhanced proliferation by a process apparently independent of an effect on cell viability or programmed cell death. 相似文献
96.
Jian-Hua Li Tuo Chen Hao Xing Rui-Dong Li Cong-Huan Shen Quan-Bao Zhang Yi-Feng Tao Zheng-Xin Wang 《Hepatobiliary & pancreatic diseases international : HBPD INT》2023,22(3):245-252
Background: Liver transplantation(LT) is the “cure” therapy for patients with hepatocellular carcinoma(HCC). However, some patients encounter HCC recurrence after LT. Unfortunately, there is no effective methods to identify the LT patients who have high risk of HCC recurrence and would benefit from adjuvant targeted therapy. The present study aimed to establish a scoring system to predict HCC recurrence of HCC patients after LT among the Chinese population, and to evaluate whether these patients... 相似文献
97.
Weaver CH; Buckner CD; Longin K; Appelbaum FR; Rowley S; Lilleby K; Miser J; Storb R; Hansen JA; Bensinger W 《Blood》1993,82(7):1981-1984
Five syngeneic transplants were performed in four patients following myeloablative therapy using unmodified peripheral blood mononuclear cells (PBMCs) collected after the administration of recombinant human granulocyte colony stimulating factor (rhG-CSF) to normal donors. The only toxicity experienced by the four normal donors was bone pain. Four patients received two collections of PBMCs, and a second transplant was performed in one patient with one collection. The patients received a median of 20.53 x 10(8) total nucleated cells/kg (range 20 to 25.5), 11.3 x 10(8) total mononuclear cells/kg (range 6.52 to 17.2), 113.1 x 10(4)/kg CFU-GM (range 46.7 to 211.8) and 9.6 x 10(6) CD34+ cells/kg (range 1.6 to 12.6) Post-transplant growth factors were not administered. The median time to an absolute neutrophil count greater than 0.5 x 10(9)/L was 14 days (range 10 to 18). The median time to platelet transfusion independence was 11 days (range 10 to 13). Two patients had the number of CD3+ T lymphocytes determined in the pheresis product. An average of 3.04 x 10(10) CD3+ cells were collected per pheresis. This represents an approximate 1 log increase over the number of T lymphocytes in a typical bone marrow transplant. Rh-GCSF can be used to mobilize peripheral blood progenitor cells from normal donors with minimal toxicity. Studies of allogeneic transplants using PBMCs collected after rhG-CSF administration to determine permanent grafting ability and the incidence and severity of graft-versus-host disease are warranted. 相似文献
98.
99.
100.
CH Shiboski 《Oral diseases》2002,8(S2):44-48
OBJECTIVES: The goals of this literature review were to (1) update a prior review [Shiboski CH (1997) The epidemiology of HIV-related oral manifestations in women: a review. Oral Dis 3: S18–S27] of studies on the epidemiology of HIV-related oral manifestations in women prior to the availability of highly active antiretroviral therapy (HAART); (2) explore the effect of HAART on HIV-related oral disease among women; and (3) explore future research directions with respect to HIV-related oral disease epidemiology among African women.
METHODS: A computer-assisted search was conducted to identify studies on the prevalence of oral conditions in HIV-infected women in relation to immunological markers and HAART [excluding studies reviewed in Shiboski CH (1997) The epidemiology of HIV-related oral manifestations in women: a review. Oral Dis 3: S18–S27]. Results were summarized and discussed for (1) studies conducted in the developed world prior to and during the era of HAART; and (2) studies conducted in sub-Saharan Africa.
RESULTS: Candidiasis (OC) is the most common oral lesion among HIV-infected women, and has been found to be associated with a low CD4 count and a high plasma viral load. Preliminary findings suggest that HAART is associated with a decreasing OC incidence. The few studies identified on HIV-related oral disease in African women suggest that OC is also a common condition in this setting.
CONCLUSION: Future oral epidemiology research efforts in Africa should focus on the potential role of OC as sentinel marker of HIV infection and disease progression, to improve detection and prevention of selected opportunistic illnesses. 相似文献
METHODS: A computer-assisted search was conducted to identify studies on the prevalence of oral conditions in HIV-infected women in relation to immunological markers and HAART [excluding studies reviewed in Shiboski CH (1997) The epidemiology of HIV-related oral manifestations in women: a review. Oral Dis 3: S18–S27]. Results were summarized and discussed for (1) studies conducted in the developed world prior to and during the era of HAART; and (2) studies conducted in sub-Saharan Africa.
RESULTS: Candidiasis (OC) is the most common oral lesion among HIV-infected women, and has been found to be associated with a low CD4 count and a high plasma viral load. Preliminary findings suggest that HAART is associated with a decreasing OC incidence. The few studies identified on HIV-related oral disease in African women suggest that OC is also a common condition in this setting.
CONCLUSION: Future oral epidemiology research efforts in Africa should focus on the potential role of OC as sentinel marker of HIV infection and disease progression, to improve detection and prevention of selected opportunistic illnesses. 相似文献