射频皱缩刀在不同工作模式下对腋神经表面温度的影响

目的：观察肩关节镜下射频皱缩刀对腋神经表面温度的影响. 方法：实验于2005-03/06在南京医科大学附属南京第一医院骨科实验室进行.取10个新鲜肩关节标本（南京中医药大学提供）,分为肩关节持续冲洗和间断冲洗两组,模拟肩关节不稳定进行射频皱缩刀关节囊皱缩术.射频皱缩刀应用持续工作和间断工作两种不同的工作模式和1和2档能量设置,采用电动测温仪分别记录射频皱缩刀工作10,25,40,55,70 s及停止工作30 s时腋神经表面的温度. 结果：①肩关节间断冲洗组：射频皱缩刀持续工作模式下,各个时间段腋神经表面温度升高较快,2 min以后均超过70℃,最高达到85℃（3 min时）,停止工作30 s,仍为82.3℃;射频皱缩刀间断工作模式下腋神经表面温度较持续工作模式升高慢（P＜0.01）,各个时间点均不超过60℃,最高才达到58℃（70 s时）.②肩关节持续冲洗组：射频皱缩刀持续工作模式下,皱缩能量为1档和2档时,在30 s时腋神经表面的温度不差异（P＞0.05）,而连续工作1 min以上,能量为1档时,各个时间点所测温度均比能量为2档时低（P＜0.05）;射频皱缩刀间断工作模式下,皱缩能量为1档和2档时,在10,25 s时,腋神经表面温度差异不显著（P＞0.05）,40 s后,能量为1档时,腋神经表面温度比能量为2档时低（P＜0.05）.在肩关节持续冲洗和能量为1档时,射频皱缩刀在两种工作模式下,腋神经表面温度均不超过50℃. 结论：在肩关节镜下行射频皱缩术时,腋神经表面温度会明显升高,持续冲洗、间断工作模式可降低腋神经表面温度;而间断冲洗、持续工作模式可能会损伤腋神经.     

采用非骨水泥及骨水泥型假体经微创双切口全髋关节置换术后近期效果与常规手术的比较

目的对比传统全髋关节置换术和微创双切口全髋关节置换术的临床应用结果,并分析骨水泥型假体在微创手术应用中的可行性.方法以2003-05/2006-05南京医科大学附属南京第一医院骨科行全髋关节置换术的患者82例为观察对象.经知情同意,分为微创手术组32例,常规手术组50例.微创手术组接受微创双切口髋关节置换,采用Zimmer HG非骨水泥假体22例,Zimmer Versys非骨水泥假体5例,北京普鲁斯钢研公司Müller骨水泥假体5例.采用Berger提出的方法,①前侧切口采用Watson-Jones入路的近侧部,在髋关节前方,平行股骨颈纵轴线外下段投影作一长约7 cm的斜切口,"T"型切开关节囊,于小转子上方1 cm处截骨,按常规步骤置入髋臼假体.②后外侧切口长约2.5 cm,术者于大转子处经皮插入克氏针1枚,穿透臀大肌在臀中肌和梨状肌间作-软组织隧道,插入皮肤保护套管作一切口,放置股骨假体,于前方切口置入合适颈长的股骨头.常规手术组接受常规全髋关节置换术,采用LINK RIB非骨水泥假体22例,CLASSIC骨水泥假体13例,北京普鲁斯钢研公司Müllr骨水泥假体15例.所用假体均经过厂家的生物相容性、生物力学特性检测,及三期临床认证后使用.比较两组手术切口长度、手术时间、术中、术后的出血量、术后开始下床活动的时间、及术后1周、6周、3个月、6个月的髋关节Harris评分等.结果患者82例全部进入结果分析.全部病例随访6～12月,平均8个月.①微创手术组前、后方切口分别为61(5.4～7.5),3.6(3.0～4.5)cm,常规手术组为12.0(9.0～14.0)cm,两组比较差异有显著性意义(P＜0.05).②微创手术组手术时间长于常规手术组[100(90～220),80(60～150)min,P＜0.05].③术后出血量微创手术组少于常规组[(119±48),(227±153)mL,P＜0.05];但术中出血量差异无显著性意义[(252±97),(280±107)mL,P＞0.05].④微创手术的患者在术后主动直腿抬高时间短于常规组,术后开始下床活动时间明显缩短(P＜0.05),但弃拐时间两组比较差异无显著性意义(P＞0.05);微创手术组术后1周、6周髋关节Harris评分高于常规手术组但术后3个月、6个月的评分差异无显著性(P＜0.05).⑤骨水泥型假体用于全髋关节置换术时,股骨骨水泥比较难以清除,常需切除前方关节囊方能彻底清除.结论微创双切口全髋关节置换术的近期术后恢复明显优于常规手术组,但远期疗效尚无明确优势;骨水泥型假体应用于微创手术是需掌握好适应症.     

Influence of red cell water content on the morphology of sickling

The response of sickle cells with varying water content to alterations in oxygen tension has been studied. Cells that were severely dehydrated while sickled retained the characteristic sickled morphology even after prolonged reoxygenation. When the cell water content was increased by reduction of the suspending medium osmolality, the cells unsickled. Cells that were dehydrated before deoxygenation were unable to assume the spiculated morphology typical of sicked cells. This was true both for high mean cell hemoglobin concentration (MCHC) discoid sickle cells and for irreversibly sickled cells. When such cells were resuspended in hypotonic medium before deoxygenation, they sickled with the characteristic morphology of sickle cells with normal MCHC. The morphological behavior of Ca-loaded sickled cells as well as irreversibly sickled cells showed a major influence of increased hemoglobin concentration and extremely high internal viscosity. Constraint on cell morphology by putative membrane rigidity was not observed.     

Murine malaria decreases hemopoietic stem cells

The causes of anemia and immunosuppression, major outcomes of malaria, are not well established. This study was undertaken to investigate whether erythropoietin (EP) production is adequate and whether the hemopoietic stem cells (CFU-S) were affected during the course of infection. Groups of female Balb/c mice infected with Plasmodium vinckei vinckei, Plasmodium berghei, or Plasmodium chabaudi adami were exposed to five hours of simulated altitude equivalent to 22,000 ft. Plasma samples were collected for EP bioassay and radioimmunoassay (RIA). Using radioiron incorporation as an index of erythropoiesis, differences in response to infection with different species of plasmodia were observed. In general, decreases in erythropoietic activity were observed in bone marrow and spleen as the infection progressed and continued to be depressed after apparent resolution of a nonlethal infection with P. chabaudi adami. Marrow from infected and control femurs were tested for CFU-S content using the spleen colony assay. The cellularity and CFU-S content of the femoral marrow decrease as the parasitemia increases. All three species of plasmodia stimulate EP production during peak parasitemias, indicating that adequate amounts of EP are available to the erythron during malarial infection. Depletion of CFU-S and probable lack of compensatory turnover of CFU-S may contribute to the disease characteristics of malaria.     

Concerns about anti-angiogenic treatment in patients with glioblastoma multiforme

Background  

The relevance of angiogenesis inhibition in the treatment of glioblastoma multiforme (GBM) should be considered in the unique context of malignant brain tumours. Although patients benefit greatly from reduced cerebral oedema and intracranial pressure, this important clinical improvement on its own may not be considered as an anti-tumour effect.     

C-reactive protein and arterial stiffness in older adults: the Rotterdam Study

Arterial stiffness is one of the characteristics of vascular aging. Increases in pulse pressure, which reflect an increase in the stiffness of the large arteries, are associated with elevated C-reactive protein (CRP) levels. This may suggest a role of inflammation in the development of arterial stiffness. We investigated the relation between measures of arterial stiffness and CRP within the framework of the Rotterdam Study, a population-based cohort study including subjects aged 55 years and older. The carotid-femoral pulse wave velocity and the distensibility coefficient of the carotid artery were used as measures of arterial stiffness. Data on both arterial stiffness and CRP were available for 866 participants. In adjusted models, levels of CRP were linearly associated with pulse wave velocity (regression coefficient 0.088, 95% CI 0.006-0.170). Adjusted mean values of pulse wave velocity were significantly different across tertiles of CRP, being higher in the highest tertile of CRP. However, no significant association between CRP and carotid distensibility was observed.     

Serum cholesterol is a risk factor for myocardial infarction in elderly men and women: the Rotterdam Study

OBJECTIVE: To investigate the associations of serum total and HDL cholesterol with the risk of myocardial infarction in men and women of 55 years and over. DESIGN: The Rotterdam Study is a population-based prospective cohort study. In total 2453 men and 3553 women of 55 years and older were included in this study. The mean duration of follow-up was 4 years. MAIN OUTCOME MEASURES: Relative risks were estimated with Cox's proportional-hazard analysis. Cholesterol was analysed as a continuous variable and in sex-specific quartiles. RESULTS: In subjects aged 55 years and older the relative risk of myocardial infarction was 1.9 in men (95% confidence interval 1.1-3.3) and 3.2 in women (1.5-6.4) in the highest compared to the lowest serum total cholesterol quartile (Q4 vs. Q1). In men and women of 70 years and older, total cholesterol remained an important risk factor for myocardial infarction (Q4 vs. Q1 relative risk 3.2; 1.3-7.7 and 2.9; 1.3-6.6, respectively). For HDL cholesterol, the relative risk in the highest compared to the lowest quartile (Q4 vs. Q1) was 0.5 in men (0.3-0.9) and 0.4 in women (0.2-0.9). HDL cholesterol was a weaker predictor in men after the age of 70 (Q4 vs. Q1 0.8; 0.3-2.1). In women of 70 years and older the relative risk was also not significant (Q4 vs. Q1 0.6; 0.3-1.3), although the trend over the quartiles was still significant. CONCLUSION: Serum total cholesterol remains an important risk factor for myocardial infarction in men and women aged 70 years and older, whilst HDL cholesterol at older age remains important in women only.     

Enhanced blood pressure response to mild sodium reduction in subjects with the 235T variant of the angiotensinogen gene.

The relationship of high salt intake to elevated blood pressure levels has been demonstrated in most populations by cross-sectional, longitudinal, physiological, and clinical intervention studies. Variation within the angiotensinogen gene has been implicated in the genetic control of blood pressure levels and has been suggested to contribute to increased salt sensitivity. A total of 86 hypertensive men and women who had never been treated and who had participated in a 6-month randomized, placebo-controlled, clinical trial of low-sodium mineral salt (19% reduction in urinary sodium versus 12% increase in placebo group) were genotyped at the angiotensinogen M235T locus to test the hypothesis that the 235T allele is associated with a significant blood pressure response to a sodium reduction intervention whereas the 235M allele is not. After adjustment for gender and baseline blood pressure, persons with the TT and MT genotypes showed significant systolic blood pressure reductions on mineral salt compared with control subjects (P = .02 and P = .001, respectively) but not persons with the MM genotype (P = .10). Net adjusted diastolic blood pressure reductions also showed greater significance for persons with the TT and MT genotypes than for persons with the MM genotype (P = .08, P = .01, and P = .83, respectively). The net adjusted systolic and diastolic blood pressure reduction was -8.6/-3.9 mm Hg for persons with the TT genotype, -9.0/-5.2 mm Hg for the MT genotype, and -5.3/-1.0 mm Hg for the MM genotype. We conclude that the 235T allele of the angiotensinogen gene is associated with greater blood pressure decreases than the 235M allele after a sodium reduction intervention. The angiotensinogen gene accounts for some of the interindividual variation of the blood pressure response to sodium reduction.