非程控降温,—80℃冻存自体外周血干细胞的研究

目的：观察非程控降温、－80℃冻存的方法对自体外周血十细胞（APBSC）的保存效果。方法：以6％羟乙基淀粉（HES）、5％二甲基亚砜（DMSO）及4％人血白蛋白（ALB）的混合物为冷冻防护剂，将APBSC直接置于－80℃下保存，冻存前反复苏后测定APBSC的CFU－GM、BFU－E；观察移植后造血功能重建情况。结果：13例患者白细胞在十3～＋7天下降至（0．0～0．1）×10／L，白细胞（0．0～0．2）×109／L持续时间3～6天，于＋9～＋11天恢复至1．0X109／L以上．中性粒细胞绝对值（ANC）于＋9～＋11天达到0．5X109／L。血小板在＋3～＋7天下降至（2．0～21）×109／L，于＋8～＋15天恢复至20×109／L以上。CFU－GM、BFU－E回大率分别为76．5％、78．4％。结论：非程控降温、－80℃冻存是一简便、经济、有效的自体外周血于细胞保存方法。     

Mechanisms of signal change during intraoperative somatosensory evoked potential monitoring of the spinal cord.

In scoliosis surgery, intraoperative somatosensory evoked potential (SSEP) monitoring has reduced the incidence of postoperative neurologic deficits. Many factors affect the amplitude and latency of SSEP waveforms during surgery. Somatosensory evoked potential amplitude decreases with ischemia and anoxia because of temporal dispersion of the afferent volley and conduction block in damaged axons. In conjunction with surgical manipulations, minor drops in blood pressure may result in substantial SSEP changes that reverse when perfusion pressure is increased. Irreversible anoxic injury to central nervous system white matter with loss of SSEP waveforms is dependent on calcium influx into the intracellular space. Somatosensory evoked potential monitoring may be less sensitive for detecting acute insults in the presence of preexisting white matter lesions. Increased extracellular potassium from acute baro-trauma can block axonal conduction transiently even when there is no axonal disruption. Marked temperature-related drops in SSEP amplitude may occur after exposure of the spine but before instrumentation and deformity correction. Hypothermia may increase false-negative outcomes. Short-interval double-pulse stimulation may improve the sensitivity of the SSEP in detecting early ischemic changes. For neurosurgical procedures on the spinal cord the use of SSEP monitoring in improving postoperative outcome is less well established.     

Isolation of pathogenic bacteria from hospital staff apparel in Nigeria

A survey of bacteria contamination of hospital staff apparel in use in Anambra State, Nigeria, was carried out to determine the extent of contamination by clinically important bacteria. Of a total of 125 swab samples of hospital staff apparel, 72 (58%) showed bacterial contamination including 32 (70%) of 46 samples from hand gloves, 28 of 45 (62%) samples from protective gowns, and 12 of 34 (35%) samples from face-shields. The potentially pathogenic bacteria isolated were Salmonella spp, Proteus vulgaris, Shigella dysenteriae, Pseudomonas aeruginosa and Staphylococcus aureus. The isolation of clinically important bacteria from the apparel suggests the need for improved infection control measures.     

大鼠急性肺血栓栓塞后血中DBP、RBP和TTR表达降低

目的探讨急性肺血栓栓塞时维生素D结合蛋白(DBP)、维生素A结合蛋白(RBP)和甲状腺素转运蛋白(TTR)的表达变化及对代谢的影响。方法用颈静脉插管注入血栓的方法制备大鼠急性肺栓塞模型。用Western blot检测DBP、RBP和TTR蛋白水平,RT-PCR法检测肝组织中DBP、RBP和TTR的mRNA水平,放射免疫法测定FT4和25(OH)D3的血清浓度,微量荧光法测定维生素A的血清浓度。结果急性肺栓塞后血清中DBP、RBP和TTR的蛋白水平,肝组织中DBP、RBP和TTR的mRNA水平均逐渐降低;而血清中这3个结合蛋白的配体FT4、25(OH)D3和维生素A的水平明显升高。结论急性肺栓塞后血清中DBP、RBP和TTR的蛋白水平降低是由于肝细胞合成减少所致,从而释放出更多的配体。升高的25(OH)D3、维生素A和FT4分子在急性肺栓塞后的一系列病理生理变化中将发挥重要作用。     

大鼠急性肺栓塞后cytokeratin-19表达下降

目的研究急性肺血栓栓塞大鼠的肺组织中细胞角蛋白19(cytokeratin-19,CK-19)及其分解产物CYFRA21-1的表达变化。方法建立大鼠急性肺血栓栓塞模型并做肺泡灌洗。用半定量RT-PCR法和Western blot法检测CK-19的mRNA和蛋白表达;免疫组化方法检测CK-19在肺组织内的分布;放免法检测血清和肺泡灌洗液中CYFRA21-1的水平;检测动脉血氧饱和度。结果急性肺栓塞后CK-19mRNA和蛋白质水平均逐渐降低;肺泡上皮细胞CK-19的表达明显下降;血清和肺泡灌洗液中CYFRA21-1水平升高;动脉血氧饱和度呈明显下降趋势。结论急性肺栓塞不仅导致CK-19表达降低,而且分解代谢增强,因此CYFRA21-1的检测对于判断急性肺栓塞的严重程度及预后具有重要意义。     

大鼠急性肺栓塞后SMP-30表达下降及其对细胞凋亡的影响

目的：研究大鼠急性肺栓塞模型肺组织中衰老标记蛋白质30(SMP-30)的表达变化及其对Fas诱导的细胞凋亡的影响。方法:建立大鼠急性肺栓塞模型，分别在急性肺栓塞后1、8、24和48 h进行支气管肺泡灌洗，然后开胸取出肺组织。常规提取肺组织的总RNA和总蛋白，以正常组为对照，采取半定量RT-PCR的方法研究SMP-30在mRNA水平表达的变化；采用Western blotting方法进一步验证SMP-30在蛋白水平表达的变化；采用免疫组织化学方法检测大鼠肺组织中SMP-30以及肺泡巨噬细胞中IL-8在肺栓塞前后表达的变化及其组织分布情况；采用TUNEL法研究急性肺栓塞后组织细胞的凋亡情况；最后采用ELISA法检测急性肺栓塞后肺泡灌洗液中sFasL的浓度变化。结果:在大鼠急性肺栓塞后的不同时点，SMP-30的mRNA水平和蛋白水平均逐渐降低，在24和48 h下降最为明显。免疫组化研究表明SMP-30主要分布在支气管黏膜上皮细胞和肺泡上皮细胞，急性肺栓塞后SMP-30在上述细胞内的表达均明显降低。TUNEL染色发现随着SMP-30表达的降低，肺组织内出现明显的细胞凋亡现象，同时肺泡灌洗液中sFasL的浓度升高，肺泡巨噬细胞内IL-8的表达也明显升高。结论:大鼠急性肺栓塞后肺组织内SMP-30的表达明显降低，可能促进Fas－FasL细胞凋亡系统的活化。     

白细胞介素4剪接变异体在哮喘患者中的表达

目的检测哮喘患者外周血中IL-4及其变异体IL-4δ2的表达,探讨其在哮喘发病机制中的作用。方法采用半定量RT-PCR技术,检测10例哮喘患者IL-4及其变异体的表达,并与正常健康人群进行比较。结果哮喘患者IL-4表达较健康人群高,而且IL-4和IL-4δ2的比值远远高于健康人。结论IL-4和IL-4δ2表达的相对性可能在哮喘发病机制中具有重要作用,其可能是Th2细胞在不同临床疾病中功能多样性的原因之一。     

Natural and anthropogenic radioactivity levels and the associated radiation hazard in the soil of Oodalia Tea Estate in the hilly region of Fatickchari in Chittagong,Bangladesh

Radioactivity in the soil of a tea garden in the Fatickchari area in Chittagong, Bangladesh, was measured using a high-resolution HPGe detector. The soil samples were collected from depths of up to 20 cm beneath the soil surface. The activity concentrations of naturally occurring ²³⁸U and ²³²Th were observed to be in the range of 27 ± 7 to 53 ± 8 Bq kg⁻¹ and 36 ± 11 to 72 ± 11 Bq kg⁻¹, respectively. The activity concentration of ⁴⁰K ranged from 201 ± 78 to 672 ± 81 Bq kg⁻¹, and the highest activity of fallout ¹³⁷Cs observed was 10 ± 1 Bq kg⁻¹. The average activity concentration observed for ²³⁸U was 39 ± 8 Bq kg⁻¹, for ²³²Th was 57 ± 11 Bq kg⁻¹, for ⁴⁰K was 384 ± 79 Bq kg⁻¹ and for ¹³⁷Cs was 5 ± 0.5 Bq kg⁻¹. The radiological hazard parameters (representative level index, radium equivalent activity, outdoor and indoor dose rates, outdoor and indoor annual effective dose equivalents, and radiation hazard index) were calculated from the radioactivity in the soil.