兔骨髓间充质细胞分化为肌细胞的实验研究

目的　探讨兔骨髓间充质细胞 (BMSCs)体外分化为肌细胞的可能性。方法　穿刺法抽取成年新西兰兔双侧股骨骨髓 ,分离培养BMSCs ,5 -溴脱氧尿苷 (bromod eoxyuridine)标记 ,再经过 5一氮杂胞苷 (5 azacytidine)诱导或与乳鼠心肌细胞共培养 ,通过免疫细胞化学染色及透射电镜检查 ,研究其分化情况。结果　体外培养的BMSCs无论是在 5 aza诱导还是在与心肌细胞共培养的条件下 ,均有部分细胞表达横纹肌肌动蛋白 (α actin)。电镜检查显示分化后的细胞具有原始肌小节样结构。结论　成年兔BMSCs在 5 aza诱导或与心肌细胞共培养的条件下均可向肌细胞方向分化     

Alcohol-induced bone marrow damage: Status before and after a 4-week period of abstinence from alcohol with or without disulfiram

Summary The investigation described in this paper has confirmed the existence of alcohol-induced bone marrow damage as a nosological entity in alcohol-dependent individuals. In our patients total abstinence from alcohol without disulfiram or similar drugs led to reversal of the pathological findings in peripheral blood and in bone marrow. In patients undergoing detoxification while taking disulfiram, on the other hand, the pathological bone marrow findings, especially erythropoiesis associated with impaired iron utilization, persisted. The metabolic pathway of disulfiram is discussed. It is probably justifiable to assume that the toxin responsible for alcohol-induced bone marrow damage is the ethanol metabolite acetaldehyde. The persistence of erythropoiesis with impaired iron utilization during abstinence from alcohol and treatment with disulfiram is also of importance in differential diagnosis from the myelodysplastic syndrome (MDS), and especially from refractory anaemia with ring sideroblasts (RARS). For this reason, where the situation is unclear, it is essential that a diagnosis of MDS be supported by specific investigations such as cell cultures, cytogenetic analyses, etc. It is the first time that the toxic, alcohol-like-effect of disulfiram on haematopoiesis is discussed.     

Fracture healing and bone mass in rats fed on liquid diet containing ethanol

BACKGROUND: Studies in animal models for alcohol abuse have suggested that ethanol inhibits bone growth, decreases bone formation, and increases fracture risk. METHODS: Experimental tibia fracture healing in rats fed a liquid diet containing 7.2% ethanol for 8 weeks was investigated with histological and osteodensitometric studies with respect to the control group. After 4 weeks of vitamin A- and sucrose-enriched milk containing 7.2% ethanol feeding, we created closed tibia fractures, which were then fixed with intramedullary nails, in 10 rats. After a follow-up time of 4 weeks, the rats were killed for examination. The same procedure was performed in another 10 rats, which were fed on the same diet (isocaloric modified liquid diet) but without ethanol and used as the control group. A histological scoring system was developed for fracture healing. RESULTS: Histological evaluation of fracture region revealed an average fracture healing score of 1.9 in the ethanol-fed group versus 2.6 in the control group (p = 0.014). In the test group, dual-energy x-ray absorptiometry measurements in the fracture region showed a mean bone mineral density of 0.11 +/- 0.03 g/cm(2), whereas it was 0.130 +/- 0.051 g/cm(2) in the control group (p = 0.000). The mean bone mineral content in the fracture region was 0.103 +/- 0.08 g/cm(3) in the test group versus 0.128 +/- 0.06 g/cm(3) in the control group (p = 0.000). A significant correlation was found among histological scores, bone mineral density (r = 0.64, p = 0.04), and bone mineral content (r = 0.63, p = 0.04). CONCLUSIONS: This study showed that rats fed on a diet mixed with ethanol have a histologically delayed fracture healing associated with decreased bone density and mineral content. Besides the negative effects of ethanol on bone metabolism, it also interferes with the fracture-healing process.     

Bone Marrow Triglyceride Accumulation and Hormonal Changes During Long-Term Alcohol Intake in Male and Female Rats

BACKGROUND: Chronic alcohol consumption may influence the metabolism of adipocytes, the most abundant stromal cell phenotype in bone marrow, and promote bone marrow triglyceride accretion. METHODS: Male and female rats 35 days old were fed the Lieber-De Carli liquid diet containing 36% of the calories as alcohol and were compared with pair-fed rats given an isocaloric liquid diet in which maltose-dextrin substituted for the calories supplied by alcohol. Other control rats were fed chow ad libitum. The rats were maintained on these diets for 64 days, after which the femurs were recovered and examined. RESULTS: End weights of male and female alcohol-fed rats were significantly lower than both control groups. Femur diaphyseal bone marrow triglyceride levels were significantly increased in alcohol-fed male and female rats compared with both control groups. Femur bone marrow cavity diameters were significantly increased and cortical thickness was significantly decreased by alcohol in both males and females. Serum insulin levels were significantly decreased by alcohol only in female rats compared with the ad libitum but not the pair-fed control group, and insulin-like growth factor-1 levels were significantly reduced in male and female rats given the alcohol diet compared with both controls. Male testosterone and female estradiol levels remained unchanged. Male estradiol levels were significantly increased by alcohol compared with both controls, and female progesterone levels were significantly reduced by alcohol compared with pair-fed rats. Whereas female leptin levels were unchanged by alcohol, male leptin levels were significantly increased by alcohol compared with pair-fed rats. CONCLUSIONS: Hormonal and growth factor changes during chronic alcohol consumption accompany triglyceride accumulation in diaphyseal bone marrow and may parallel the effects of alcohol on mesenchymal stem cells and the balance between osteogenic and adipogenic lineages and their cellular progenies.     

Alcohol exposure and mechanisms of tissue injury and repair

Tissue injury owing to acute and chronic alcohol consumption has extensive medical consequences, with the level and duration of alcohol exposure affecting both the magnitude of injury and the time frame to recovery. While the understanding of many of the molecular processes disrupted by alcohol has advanced, mechanisms of alcohol-induced tissue injury remain a subject of intensive research. Alcohol has multiple targets, as it affects diverse cellular and molecular processes. Some mechanisms of tissue damage as a result of alcohol may be common to many tissue types, while others are likely to be tissue specific. Here, we present a discussion of the alcohol-induced molecular and cellular disruptions associated with injury or recovery from injury in bone, muscle, skin, and gastric mucosa. In every case, the goal of characterizing the sites of alcohol action is to devise potential measures for protection, prevention, or therapeutic intervention.     

Correlation between characteristics of unrelated bone marrow donor and cell density of total nucleated cell in bone marrow harvest

The relationship between the features of bone marrow donor and the quality of marrow harvest has been unclear because most of bone marrow registries have multiple collection centers with somewhat different harvest procedures. We are able to address this issue for Tzu Chi General Hospital is the only collection center affiliated with Tzu Chi Taiwan Bone Marrow Registry. Between November 1997 and March 2002, data of 286 healthy unrelated donors was analyzed to correlate with the cell density of total nucleated cell in bone marrow harvests. The harvest procedure was standardized by single-hole harvest needle under general anesthesia. The operation staffs were restricted within the members of Oncology–Hematology division. The results showed that the cell density of bone marrow harvest was positively correlated with donor body weight and peripheral white blood cell count P = 0.0475, P < 0.0001, but negatively correlated with the total volume of bone marrow harvest P < 0.0001. We recommend that if multiple human leukocyte antigen-matched donors are available, donor with higher body weight and/or higher white blood cell count be selected for allogeneic bone marrow transplantation.     

Risk factors associated with bone loss and occurrence of fragility fractures in rheumatoid arthritis patients

Aim of the work

To investigate the bone mineral density (BMD) in rheumatoid arthritis (RA) Tunisian patients, to identify the risk factors associated with its decrease and to assess the fracture risk.

Disuse exaggerates the detrimental effects of alcohol on cortical bone

BACKGROUND: Alcohol abuse is associated with an increased risk for osteoporosis. However, comorbidity factors may play an important role in the pathogenesis of alcohol-related bone fractures. Suboptimal mechanical loading of the skeleton, an established risk factor for bone loss, may occur in some alcohol abusers due to reduced physical activity, muscle atrophy, or both. The effect of alcohol consumption and reduced physical activity on bone metabolism has not been well studied. The purpose of this study was to determine whether mechanical disuse alters bone metabolism in a rat model for chronic alcohol abuse. METHODS: Alcohol was administered in the diet (35% caloric intake) of 6-month-old male rats for 4 weeks. Rats were hindlimb-unloaded the final 2 weeks of the experiment to prevent dynamic weight bearing. Afterward, cortical bone histomorphometry was evaluated at the tibia-fibula synostosis. RESULTS: At the periosteal surface of the tibial diaphysis, alcohol and hindlimb unloading independently decreased the mineralizing perimeter, mineral apposition rate, and bone formation rate. In addition, alcohol, but not hindlimb unloading, increased endocortical bone resorption. The respective detrimental effects of alcohol and hindlimb unloading to inhibit bone formation were additive; there was no interaction between the two variables. CONCLUSIONS: Reduced weight bearing accentuates the detrimental effects of alcohol on cortical bone in adult male rats by further inhibiting bone formation. This finding suggests that reduced physical activity may be a comorbidity factor for osteoporosis in alcohol abusers.     

Hematological malignancies diagnosed by bone marrow examination in a tertiary hospital at Uttarakhand,India

Introduction

Hematological malignancies are quite common and affect all ages and genders. The diagnosis involves a multiparameter approach. The geographical distribution of various types of hematological malignancies has been provided by various authors but no such data have been published regarding the State of Uttarakhand in India.

Aim

To study the hematological malignancies at Uttarakhand in India based on age, sex and the type of malignancy with further sub typing wherever possible.

Settings and design

A total of 220 cases of hematological malignancies were worked up from the Reference Laboratory of Himalayan Institute of Medical Sciences over an eight year period (1998–2005).

Materials and methods

Diagnosis was mainly based on morphological examination of peripheral blood and bone marrow smears stained by Leishman’s stain and MPO, Sudan Black and PAS stain as and where required. Distribution of cases was studied based on age, sex and the type of malignancy with further sub typing wherever possible.

Results

The most common hematological malignancy was found to be Leukemia 129/220 (58%) followed b Lymphoma 33/220 (14.8%), Multiple Myeloma 55/220 (24.7%) and Metastatic Lesions 3/220 (1.3%). These malignancies were seen to be distributed throughout all ages with a peak at 11–20 years age group 39/220 (17.5%) and another peak at 51–60 years age group 41/220 (18.4%). We found an overall male preponderance with a M:F ratio of 2.3:1.

Conclusions

The commonest haematological malignancy in our series was Leukemia. Other diagnoses were Multiple Myeloma, Lymphoma and Secondaries. Multiple Myeloma which turned out to be the second most common diagnosis was an unusual finding.

     

Successful bone marrow transplantation from an unrelated donor in a child with AML in second remission

Summary In February 1986 we transplanted a 10-year-old girl with AML in second remission with the bone marrow of an unrelated donor. HLA-types were different for one A- and one B-antigen between patient and donor. Conditioning regimen consisted of 14 Gy total body irradiation with lung shielding, 8×3 g/m² cytosin arabinoside and 90 mg/kg cyclophosphamide. GVHD-prophylaxis was performed with cyclosporin A, methotrexate and prednisolone. Only mild GVHD I of the skin could be observed after rapid engraftment. 100 days after transplantation the patient was in good clinical condition and GVHD-prophylaxis was discontinued without any reactivation of acute or chronic GVHD. Engraftment was documented by sex chromosome and blood group typing. 120 days after transplantation leukemic blasts were detected in the peripheral blood and the child died 130 days after BMT from relapse of the leukemia. Despite the negative outcome, this was the first successful bone marrow transplantation from a unrelated donor in Germany.Supported by the Deutsche Forschungsgemeinschaft (Sonderforschungsbereich 120)These authors represent the bone marrow transplantation team in Tübingen     

骨髓间充质干细胞移植治疗病毒性心肌炎研究的进展

骨髓间充质干细胞(BM-MSCs)移植是一种新兴的治疗病毒性心肌炎(VMC)方法。本文从BM-MSCs的免疫调节、抗氧化、非免疫原性及异基因BM-MSCs的应用等方面阐述其在VMC治疗中的生物学功能,从而为治疗VMC提供新方向。     

兔骨髓间充质干细胞自体移植及血管新生修复梗死心肌的实验研究

目的　了解骨髓间充质干细胞 (MSCs)在心肌梗死的缺血心肌微环境中转化为心肌细胞并改善心功能的可行性。方法　结扎兔左前降支 (LAD)制作急性心肌梗死(AMI)模型 ,骨穿抽取骨髓 ,分离培养扩增骨髓间充质干细胞。术后 2周进行心肌梗死瘢痕内移植 5溴脱氧尿嘧啶(BrdU)标记的骨髓间充质干细胞 ,对照组注射培养基。AMI术前、AMI术后 3d及移植后 4周做超声心动图检测心功能 ,移植后 4周从右颈总动脉插管至左心室测左室压力变化 ,随后处死动物模型 ,取左室标本做冰冻切片 ,采用免疫荧光方法检测BrdU鉴定植入细胞并检测Ⅷ因子相关抗原以测量毛细血管密度。结果　细胞移植组左室切片中可见BrdU染色阳性细胞即植入细胞 ,对照组未见BrdU染色阳性细胞。Ⅷ因子阳性内皮细胞计数表明细胞移植组毛细血管密度大于对照组 (P <0 0 5 )。超声心动图检查证实MSCs移植后 4周左室收缩末期直径 (LVESD)、舒张末期直径 (LVEDD)均小于对照组 (分别为P <0 0 1及P <0 0 5 ) ,小轴缩短率 (ΔD % )、射血分数 (EF)均大于对照组 (均P <0 0 1)。结论　兔缺血心肌内注射骨髓间充质干细胞可依赖组织微环境转化为心肌细胞修复梗死心肌 ,可能伴有移植区域新生血管形成 ,能显著改善心功能 ,可用于心肌梗死的治疗。     

Ethanol and acetaldehyde inhibit the formation of early osteoblast progenitors in murine and human bone marrow cultures

Alcohol abuse is commonly associated with reduced bone mass and osteoporosis as a consequence of both systemic and direct cellular effects. To clarify some of the pathways by which alcohol exerts its actions directly on bone cells, we investigated the formation of early osteoblast progenitors (colony-forming units for fibroblasts; CFU-F) in long-term murine and human bone marrow cultures exposed to ethanol and to its main metabolite, acetaldehyde. In murine bone marrow cultures, obtained from Swiss female mice, ethanol inhibited CFU-F formation (maximal reduction +/- SEM: 50 +/- 2%; p < 0.01) at concentrations ranging from 0.04% to 0.6% that are similar to those reached in vivo in alcoholics. Acetaldehyde strongly reduced CFU-F formation at concentrations of 0.004% and 0.02%, and completely abolished it at the dose of 0.06%. Similarly, ethanol (at concentrations > or =0.02%) and acetaldehyde (from 0.004% to 0.06%) significantly decreased the number of CFU-F in human bone marrow cultures; the mean reduction observed with ethanol was 63 +/- 12% (p < 0.05), whereas acetaldehyde completely prevented CFU-F formation at the concentration of 0.06%. These in vitro observations were confirmed by the in vivo findings that the CFU-F formation in bone marrow cultures from nine young, chronic, noncirrhotic alcoholics was significantly reduced (70 +/- 15%), compared with seven age-matched normal subjects (p < 0.01). In addition, acetaldehyde inhibited cell proliferation in human osteoblastic cells (MG-63 and HOBIT cell lines), whereas ethanol reduced proliferation only in MG-63 cells. Our results indicate that ethanol and acetaldehyde may directly inhibit the osteoblastogenic potential of the bone marrow, and this effect may contribute to the decreased bone formation observed in alcoholics.     

Effects of ossein-hydroxyapatite compound on ewe bone remodeling: Biochemical and histomorphometric study

Summary Ossein-hydroxyapatite compound (OHC) is a protein-mineral complex derived from bovine bone. Its effects on bone remodeling were studied in old ewes which have seasonal variations in bone remodeling. Seven animals received 200 mg OHC/kg b.w./day for 90 days from July to September. The control group consisted of 7 untreated animals followed for the same period of time. OHC was administered through a fistula into the fourth stomach. A significant decrease of bone histomorphometric parameter values was noted in controls at the end of the experiment, due to seasonal variations: the cancellous eroded perimeter decreased by 45%, the osteoblastic perimeter by 60% and the bone formation rate at the cell level by 20%. In contrast, in the treated-group, these parameters tended to increase or did not change. In conclusion, counteracting the significant seasonal reduction of bone remodeling in ewes, OHC seems able to stimulate directly or indirectly bone metabolism, especially when osteoblast activity is reduced and may partly prevent the seasonal reduction of bone turnover.     

Long-term sequelae of Pelvis irradiation: Histological and microradiographical study of a femoral head

Summary Despite the lack of radiological signs, a femoral head showed histological and microradiographical features of osteonecrosis, 54 years after massive irradiation of the right hip. Intertrabecular spaces were invaded by connectivo-vascular tissue with focal accumulation of mast cells, and several resorption foci were filled with mononucleated cells. Moreover, all the microradiographs showed peculiar hypercalcified lines, sometimes containing empty osteocytic lacunae, the origin of which is difficult to precise. This study suggests that massive irradiation of weight-bearing epiphyses may be responsible for particularly long-term hypovascularity, osteonecrosis and disturbed bone remodeling.     

Alcohol-induced hypertension: Mechanism and prevention

Epidemiological, preclinical and clinical studies es-tablished the association between high alcohol con-sumption and hypertension. However the mechanism through which alcohol raises blood pressure remains elusive. Several possible mechanisms have been pro-posed such as an imbalance of the central nervous system, impairment of the baroreceptors, enhanced sympathetic activity, stimulation of the renin-angio-tensin-aldosterone system, increased cortisol levels, increased vascular reactivity due to increase in intracel-lular calcium levels, stimulation of the endothelium to release vasoconstrictors and loss of relaxation due to inflammation and oxidative injury of the endothelium leading to inhibition of endothelium-dependent nitric oxide production. Loss of relaxation due to inflamma-tion and oxidative injury of the endothelium by angio-tensin II leading to inhibition of endothelium-dependent nitric oxide production is the major contributors of the alcohol-induced hypertension. For the prevention of alcohol-induced hypertension is to reduce the amount of alcohol intake. Physical conditioning/exercise trainingis one of the most important strategies to prevent/treat chronic alcohol-induced hypertension on physiological basis. The efficacious pharmacologic treatment includes the angiotensin-converting enzyme(ACE) inhibitors or angiotensin Ⅱ type 1 receptor blockers(ARBs) which have antioxidant activity and calcium channel blockers. The most effective prevention and treatment of alcohol-induced hypertension is physical exercise and the use of ACE inhibitors or ARBs in the clinic