高脂血症患者血小板体积及有关参数的研究

本文报道242例高脂血症患者血小板(PLT)、平均血小板数(MPLT)及平均血小板体积(MPV)等参数的测定结果,其中高胆固醇并高甘油三酯患者,PLT、MPLT及巨大血小板比例(Macro-PLT)高于正常,MPV正常;而单纯高胆固醇或高甘油三酯患者,上述指标与正常人无显著性差异。提示高胆固醇并高甘油三酯患者,存在血小板生成动力学异常,其血小板的破坏增加,生成率加速、但处于一种高水平的动态平衡之中。这可能是高脂血症出现高凝状态的原因之一。同时表明此类患者使用抗血小板疗法具有一定的合理性和必要性。     

新疆出血热病毒与流行性出血热病毒的生物学特性比较

本文通过免疫荧光(IF)和电镜(EM)技术对新疆出血热(XHF)及流行性出血热(EHF)病毒的生物学特性在Vero E_6及LLC-MK_2两株传代细胞上进行了比较。两种病毒感染两株细胞后免疫荧光染色有两种不同的荧光形态特征,两种病毒对细胞的敏感性明显不同,XHF病毒在LLC-MK_2细胞上感染后6～8天可出现明显的细胞病变,而EHF病毒感染此细胞后则不引起病变。电镜观察到两种病毒在LLC-MK_2细胞中都能形成与布尼病毒相似的形态特征。     

γ线照后大鼠胃组织乙酰胆碱含量胆碱酯酶活性及平滑肌对乙酰胆碱反应性的变化

本文以大鼠为实验对象,观察了γ线8Gy照后胃组织内乙酰胆碱含量、胆碱酯酶活性及平滑肌对乙酰胆碱反应性的变化。结果表明,照后1/24～l天胃组织内乙酰胆碱含量明显下降,3天趋向正常,5天基本恢复至照前水平。胃组织的胆碱酯酶活性在照后l/24～5天基本无改变。在同一剂量照后1h,胃窦平滑肌对乙酰胆碱的反应与照前近似,l天后开始减弱,3天后明显下降,与正常相比有非常显著差异。     

Central Nervous System Lymphomatoid Granulomatosis Presenting with Parkinsonism

Lymphomatoid granulomatosis (LG) is a potentially malignant lymphoproliferative disorder. The lung is the most common involved site, followed by the skin and nervous system. However, LG of the central nervous system presenting with Parkinsonism is very rare. We report a patient with LG who presented with parkinsonian features such as bilateral rigidity, bradykinesia, and agitation. Brain magnetic resonance imaging showed multifocal punctuate enhanced lesions in both supra- and infratentorial areas. Steroid pulse therapy resulted in a dramatical improvement in the symptoms and MRI abnormalities.     

Differential gene expression in cultured osteoblasts and bone marrow stromal cells from patients with Paget's disease of bone.

Paget's disease is a focal condition of bone. To study changes in cells within pagetic lesions, we cultured osteoblasts and stromal cells from 22 patients and compared gene expression in these cells to cells from healthy bone. We identified several differentially regulated genes, and we suggest that these changes could lead to the formation of the lesions. INTRODUCTION: Paget's disease is a focal condition of bone of unknown cause. Although it is regarded as primarily an osteoclast disorder, the tight coupling of the activity of osteoclasts and osteoblasts suggests that the osteoblast could play a key role in its pathogenesis. The aim of the study was to identify possible changes in pagetic osteoblasts and stromal cells that might contribute to the development of pagetic lesions. MATERIALS AND METHODS: Candidate genes were identified based on known bone cell regulators, supplemented with microarray analysis. Gene expression was determined by real-time PCR in primary cultures of osteoblasts and bone marrow stromal cells from pagetic patients and control subjects. Concentrations of secreted proteins were determined by ELISA. RESULTS: Dickkopf1 mRNA and protein levels were increased in both pagetic osteoblast and stromal cell cultures, and interleukin (IL)-1 and IL-6 were overexpressed in pagetic osteoblasts. These changes parallel recent findings in myeloma bone disease, which shares some clinical similarities with Paget's disease. Alkaline phosphatase was overexpressed, and bone sialoprotein and osteocalcin were underexpressed in pagetic osteoblasts, consistent with their circulating levels in pagetic patients. It is hypothesized that overexpression of Dickkopf1, IL-1, and IL-6 would result in stimulation of osteoclast proliferation and inhibition of osteoblast growth, leading to the development of the characteristic lytic bone lesions. By stimulating osteoblast differentiation, Dickkopf1 and IL-6 may also promote mineralization, leading to the conversion of lytic lesions to sclerotic. CONCLUSIONS: These findings suggest that dysregulated gene expression in pagetic osteoblasts could cause the changes in bone cell number and function characteristic of Paget's disease.     

Enhanced chondrogenesis and Wnt signaling in PTH-treated fractures.

Studies have shown that systemic PTH treatment enhanced the rate of bone repair in rodent models. However, the mechanisms through which PTH affects bone repair have not been elucidated. In these studies we show that PTH primarily enhanced the earliest stages of endochondral bone repair by increasing chondrocyte recruitment and rate of differentiation. In coordination with these cellular events, we observed an increased level of canonical Wnt-signaling in PTH-treated bones at multiple time-points across the time-course of fracture repair, supporting the conclusion that PTH responses are at least in part mediated through Wnt signaling. INTRODUCTION: Since FDA approval of PTH [PTH(1-34); Forteo] as a treatment for osteoporosis, there has been interest in its use in other musculoskeletal conditions. Fracture repair is one area in which PTH may have a significant clinical impact. Multiple animal studies have shown that systemic PTH treatment of healing fractures increased both callus volume and return of mechanical competence in models of fracture healing. Whereas the potential for PTH has been established, the mechanism(s) by which PTH produces these effects remain elusive. MATERIALS AND METHODS: Closed femoral fractures were generated in 8-wk-old male C57Bl/6 mice followed by daily systemic injections of either saline (control) or 30 microg/kg PTH(1-34) for 14 days after fracture. Bones were harvested at days 2, 3, 5, 7, 10, 14, 21, and 28 after fracture and analyzed at the tissue level by radiography and histomorphometry and at the molecular and biochemical levels level by RNase protection assay (RPA), real-time PCR, and Western blot analysis. RESULTS: Quantitative muCT analysis showed that PTH treatment induced a larger callus cross-sectional area, length, and total volume compared with controls. Molecular analysis of the expression of extracellular matrix genes associated with chondrogenesis and osteogenesis showed that PTH treated fractures displayed a 3-fold greater increase in chondrogenesis relative to osteogenesis over the course of the repair process. In addition, chondrocyte hypertrophy occurred earlier in the PTH-treated callus tissues. Analysis of the expression of potential mediators of PTH actions showed that PTH treatment significantly induced the expression of Wnts 4, 5a, 5b, and 10b and increased levels of unphosphorylated, nuclear localized beta-catenin protein, a central feature of canonical Wnt signaling. CONCLUSIONS: These results showed that the PTH-mediated enhancement of fracture repair is primarily associated with an amplification of chondrocyte recruitment and maturation in the early fracture callus. Associated with these cellular effects, we observed an increase in canonical Wnt signaling supporting the conclusion that PTH effects on bone repair are mediated at least in part through the activation of Wnt-signaling pathways.     

Radiation effects on the cosmetic outcomes of immediate and delayed autologous breast reconstruction: an argument about timing.

OBJECTIVE: To conduct a systematic review to gather the available evidence on the optimum timing of the radiotherapy in relation to autologous breast reconstruction. MATERIAL AND METHODS: The data was extracted from scientific databases, and a manual follow-up of references. The studies were selected which included at least 20 patients with any method of autologous breast reconstruction who were treated with adjuvant radiotherapy either before or after their reconstruction, and had addressed the effects of radiotherapy on the cosmetic outcome in their results. The principal outcome was cosmetic appearance. Secondary outcomes were immediate and delayed complications. RESULTS: We could not find any randomised controlled trial on this topic. Ten studies were included, most were retrospective, heterogeneous in terms of control groups, radiation doses, follow-up duration, and outcome measurements. Two studies included no control groups, and four studies compared the outcomes of patients with radiotherapy either before (n=3) or after (n=1) autologous breast reconstruction. The overall incidence of complications was increased in patients with radiotherapy in three out of these four studies. Only four studies directly compared the outcomes of patients who received radiotherapy before with patients who received radiotherapy after autologous breast reconstruction and two out of these reported worse outcomes associated with post-reconstruction radiotherapy. CONCLUSIONS: Despite the paucity of the published data, the current evidence suggests that the radiation has a deleterious effect on autologous flap reconstruction. Until better methods of radiation delivery can be devised to minimise the long term radiation sequelae in the irradiated tissue, delayed reconstruction seems to be a safe option in most of the cases. However, the findings from these studies should be interpreted with great caution before generalising from their results.     

Effects of cerulenin on the endogenous fatty acid synthetic activity in squamous cell carcinoma of the oral cavity.

PURPOSES: Inhibition of cerulenin on the endogenous fatty acid synthetic activities of oral squamous cell carcinoma (OSCC) and normal oral mucosa was assayed. METHODS: Squamous cell carcinoma and normal oral mucosa were collected fresh from surgical specimens. The collected tissues were minced in RPMI 1640 and divided into 3 groups: cerulenin treated, dimethylsulfoxide treated, and control. The tissues were incubated in [1(2)-(14)C]acetic acid, sodium salt for the last 2.5 hours of the treatment at 37 degrees C in 5% CO(2). After labeling, total lipids were extracted and counted for (14)C by scintillation counting. RESULTS: Endogenous fatty acid synthetic activities of oral squamous cell caranoma in the cerulenin-treated group decreased by 19% at 1 hour, 64% at 2 hours, and 87% at 4 hours; remained nearly unchanged in the dimethylsulfoxide-treated group; and increased slightly in the control group. The oral mucosa tissues were only mildly affected by cerulenin in fatty acid synthesis. CONCLUSIONS: Cerulenin significantly inhibits fatty acid synthetic activity in squamous cell carcinoma and only mildly affected the oral mucosa, indicating that the fatty acid synthetic pathway may be exploited as a target for developing anticancer drugs.     

Chemical analysis of powder and set forms of Portland cement, gray ProRoot MTA, white ProRoot MTA, and gray MTA-Angelus.

OBJECTIVE: To evaluate the chemical composition and crystalline structures of Portland cement, gray ProRoot MTA (gray MTA), white ProRoot MTA (white MTA), and gray MTA-Angelus. STUDY DESIGN: X-ray diffraction analysis was used to identify and characterize crystalline phases, and energy dispersive x-ray spectrometer was used to determine the chemical composition of the test materials. Both powder form and set form were examined. RESULTS: The crystalline structure and chemical composition of gray and white MTA were similar except for the presence of iron in gray MTA. Both were composed mainly of bismuth oxide and calcium silicate oxide. Portland cement was composed mainly of calcium silicate oxide and did not contain bismuth oxide. Gray MTA-Angelus had a lower content of bismuth oxide than ProRoot MTA. There were no noticeable differences in the chemical composition and crystalline structures between the powder and set forms of any of the material tested. CONCLUSION: Portland cement differed from the MTA by the absence of bismuth ions and presence of potassium ions. Gray MTA contained a significant amount of iron when compared with white MTA. In addition, gray MTA-Angelus had a lower content of bismuth oxide than ProRoot MTA.