Digital imaging of the chest

During the past several years, image acquisition in nuclear medicine, computed tomography, ultrasonography, subtraction angiography, and magnetic resonance has been by digitization. Despite these advances, research in the development of digital imaging in conventional radiography has lagged behind. Although studies with a variety of digital techniques have been carried out on several fronts, we still do not possess a method that has captured the imagination of the majority of radiologists and other physicians to a point where it could replace conventional screen-film imaging. This article reviews the current status and general principles of the technology, focusing on the four digital radiographic techniques that have shown the greatest promise - film digitization, an image intensifier - based system, photostimulable phosphor plates, and a scanned projection system. The physical aspects of each of the four systems and the clinical results that have been reported to date, as well as the advantages and disadvantages of each system, are presented.     

MR imaging of facial nerve enhancement in Bell palsy or after temporal bone surgery

The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding.     

N-乙酰半胱氨酸对脑死亡状态巴马小型猪肾脏结构、功能与核转录因子κB表达的影响

目的：观察核转录因子κB活性抑制剂N-乙酰半胱氨酸对脑死亡状态下巴马小型猪肾脏结构、功能与核转录因子κB mRNA其蛋白表达的影响，以期提高脑死亡供肾的肾移植效果。方法：实验于2003—08／2004—12在河南省实验动物中心及河南省病理学重点实验室完成。①实验分组及方法：将15只巴马小型猪按随机数字表法分为3组（n=5），即脑死亡组、N-乙酰半胱氨酸组及对照组。脑死亡组和N-乙酰半胱氨酸组均应用改进的缓慢间断颅内加压法建立脑死亡模型，脑死亡组不行药物干预；N-乙酰半胱氨酸组分别于初次确认脑死亡后1h，12h给予N-乙酰半胱氨酸。对照组动物麻醉后仅行开颅与开关腹手术。②实验评估：分别于首次判定脑死亡后3，6，12，18和24h检测动物血清中尿素氮、肌酐、白细胞介素1β、白细胞介素6、肿瘤坏死因子α水平。于脑死亡后3，6，12及24h开腹取相同部位肾组织，苏木精-伊红染色后观察肾组织结构变化，应用免疫组化染色观察核转录因子κB蛋白的表达水平，应用反转录-聚合酶链反应法检测核转录因子κB mRNA动态变化。结果：15只猪均进入结果分析。①自首次判定脑死亡后12h开始，脑死亡组和N-乙酰半胱氨酸组尿素氮和肌酐水平逐渐升高（P〈0．05），相同时间点比较N-乙酰半胱氨酸组显著低于脑死亡组（P〈0．05）。②自首次判定脑死亡3h开始，脑死亡组及N-乙酰半胱氨酸组白细胞介素1β、白细胞介素6、肿瘤坏死因子α逐渐升高（P〈0．05），相同时间点比较N-乙酰半胱氨酸组显著低于脑死亡组（P〈0．05）。③自脑死亡后3h开始，脑死亡组及N-乙酰半胱氨酸组肾组织NF-κB mRNA其蛋白表达水平逐渐升高（P〈0．05），相同时间点比较N-乙酰半胱氨酸组显著低于脑死亡组（P〈0．05）。④N-乙酰半胱氨酸组和脑死亡组动物脑死亡后12h可见肾脏结构变化，N-乙酰半胱氨酸组变化程度明显轻于脑死亡组。结论：N-乙酰半胱氨酸可能通过抑制核转录因子κB mRNA其蛋白的表达，减少炎症介质的释放，从而保护脑死亡状态下肾脏的功能及结构，提高脑死亡供肾肾移植效果。     

Clinical significance of anti-Yt(b). Report of a case using a 51chromium red cell survival study

Several published reports have documented the variable survival of Yt(a+) red cells (RBC) in patients with anti-Yt(a) as measured by 51Chromium (Cr)-labeled RBC survival studies. Similar studies with anti-Yt(b) have not been reported. A 51Cr-labeled RBC survival study was performed using Yt(b+) RBCs and a monocyte monolayer assay in a young hemodialysis patient who required chronic transfusion therapy and who had developed anti-Yt(b). The survival of the transfused RBCs was 100 and 93 percent at 1 and 24 hours, respectively, with a half life of 21 days at termination of the study (normal, 28 to 32 days). These results showed no evidence of rapid destruction of the Yt(b+) RBCs, indicating that this patient could be transfused safely with blood from Yt(b+) donors. Long-term survival of the 51Cr-labeled Yt(b+) RBCs was shortened moderately, however, a finding that correlated with a slightly abnormal monocyte monolayer assay test.     

肾移植术后卡氏肺囊虫肺炎5例回顾性分析

目的:观察肾移植术后卡氏肺囊虫肺炎的发生率及治疗效果。方法:选择2003-01/2005-12在中山市人民医院行肾移植的患者112例,患者均知情同意。按是否使用猪抗人淋巴细胞免疫球蛋白分为2组,基础免疫抑制组(n=68)给予环孢素A/他克莫司 吗替麦考酚酯 强的松;抗体诱导组(n=44)给予猪抗人淋巴细胞免疫球蛋白 环孢素A/他克莫司 吗替麦考酚酯 强的松。两组共发生卡氏肺囊虫肺炎5例,其中基础免疫抑制组2例,抗体诱导组3例。5例患者通过普通抗感染治疗,3～7d病情未见好转,遂行支气管镜活检 深部吸痰培养,尽早明确病原体,指导抗菌治疗。比较两组患者卡氏肺囊虫肺炎的发生率,并观察其治疗效果。结果:5例卡氏肺囊虫肺炎患者全部进入结果分析,无脱落。①5例患者经支气管纤维镜肺组织活检确诊为卡氏肺囊虫肺炎,发生率为4.46%,其中抗体诱导组6.82%(3/44)明显高于基础免疫抑制组2.94%(2/68)。②5例卡氏肺囊虫肺炎中2例合并金黄色葡萄球菌感染。以复方磺胺甲恶唑为基础药物进行综合治疗,3例患者临床治愈出院,随访3个月,移植肾及肺功能正常;死亡2例。③5例患者治疗期间均无排斥反应发生。④在发病初期5例患者的CD4/CD8平均值为1.02±0.15,3例治愈患者的CD4/CD8平均值为1.42±0.23,在恢复过程中逐渐升高。2例死亡患者的CD4/CD8平均值为1.10±0.21。结论:早期支气管纤维内镜活检对肾移植术后卡氏肺囊虫肺炎的诊断非常重要,早期诊断、早期治疗是治愈的关键。猪抗人淋巴细胞免疫球蛋白可增加肾移植术后卡氏肺囊虫肺炎的发生率。     

人白细胞介素24mRNA在瘢痕疙瘩中的表达及意义

目的:从基因水平测量瘢痕疙瘩组织中白细胞介素24的表达水平,探讨白细胞介素24在瘢痕疙瘩发生、发展过程中的作用和意义。方法:实验于2005-10/2006-09在广东医学院整形外科研究所完成。①选取2004-06/2005-10广东医学院附属医院整形外科收治的患者,瘢痕疙瘩标本12例,正常瘢痕标本10例,行巨乳缩小、除皱术、植皮等患者正常皮肤标本12例,患者均知情同意且自愿捐献标本,实验经医学伦理委员会批准。标本取材部位为颜面、前胸、四肢等,切取后液氮保存。②低温条件下切取秤量组织,采用Trizol法提取总RNA。电泳鉴定总RNA完整性,并统一调整总RNA含量为10g/L,-70℃储存。RT-PCR二步法合成cDNA。③以正常皮肤、正常瘢痕为对照,以GAPDH作为扩增内参照基因,将正常皮肤、正常瘢痕和瘢痕疙瘩各类标本总RNA反转录的cDNA模板浓度调整相对一致进行扩增反应。以白细胞介素24mRNA与GAPDHmRNA的光密度积分值之比作为各类组织标本中白细胞介素24的相对含量,比较白细胞介素24mRNA在正常皮肤、正常瘢痕及瘢痕疙瘩组织中的表达情况。结果:①各类组织标本中总RNA抽提结果:正常皮肤、正常瘢痕和瘢痕疙瘩组织中抽提总RNA经甲醛变性凝胶电泳后显示较清晰的18s和28s条带,经紫外分光光度计测定A260/A280≈2.0。②各类组织标本中白细胞介素24mRNA的表达:白细胞介素24和GAPDH基因表达产物通过RT-PCR方法得到的特异性DNA片段长度分别为173bp和577bp。瘢痕疙瘩的白细胞介素24mRNA与GAPDHmRNA的吸光度比值明显低于正常皮肤、正常瘢痕(0.577±0.113,1.070±0.185,1.139±0.195;t=7.436×10-8～4.745×10-8,P均<0.01),正常皮肤与正常瘢痕白细胞介素24mRNA的相对表达量基本一致(t=0.405,P>0.05)。结论:瘢痕疙瘩的形成可能与白细胞介素24在组织中的表达降低有关。提示采用基因疗法提高早期瘢痕疙瘩中白细胞介素24的含量与活性,可能为瘢痕疙瘩的康复治疗提供有效途径。     

Blood loss and replacement in total hip arthroplasty: a multicenter study. The Preoperative Autologous Blood Donation Study Group

To determine blood loss, the number of transfusions, and the hemoglobin levels achieved in patients via transfusion in the course of total hip arthroplasty, 324 patient records from 1987 through 1989 were reviewed at three university and three community hospitals. Calculated blood loss was 3.2 +/- 1.3 units in primary procedures and 4.0 +/- 2.1 units in revision procedures (mean +/- SD). Of 777 red cell units transfused, 455 (59%) were autologous units. Transfused patients received 2.0 +/- 1.8 units for primary procedures and 2.9 +/- 2.3 units for revision procedures (mean +/- SD). The maximum number of units given to 95 percent of the transfused patients was 4 for primary procedures and 6 for revision procedures. The mean postoperative hemoglobin level after all transfusions was 103 to 110 g per L, regardless of patient age group of physical status, autologous donor status, or hospital. No difference in length of hospital stay was observed for patients less than 65 years old with hemoglobin concentrations of 80 to 139 g per L at discharge.     

Monitoring for undertransfusion

BACKGROUND: Most published reviews and audits of blood and blood component transfusion have focused on the issue of overtransfusion and on the inappropriate use of red cell components. There is growing concern that efforts to curb unnecessary transfusions may result in a trend toward undertransfusion of patients. There is little published information that addresses this issue or the magnitude of this practice. STUDY DESIGN AND METHODS: Undertransfusion was evaluated by examining the transfusion records from a 3-month period for 55 patients who met the study criteria of having either a hemoglobin level < 7 g per dL or a platelet count of < 10 × 10(9) per L. If the identified patient did not receive a transfusion within 24 hours of the reported hemoglobin level or platelet count, the medical record was reviewed by a resident physician. RESULTS: A total of 213 individual hemoglobin levels and platelet counts, representing the 55 patients, met our transfusion criteria. All except 8 of the identified patients received red cells and/or platelet transfusions. Reasons for not transfusing red cells included the patient's response to nutritional support and iron supplementation, refusal of blood, and noncompliance. Reasons for not transfusing platelets included falsely low platelet count because of platelet clumping in vitro, contraindication based on clinical diagnosis (e.g., immune thrombocytopenic purpura), and the patient's death before transfusion. CONCLUSION: Red cell and platelet transfusions were appropriately ordered for all patients who met the transfusion criteria. Undertransfusion is not a problem at this institution according to the criteria established. It is recommended that other institutions expand their blood utilization audits to include investigation for evidence of undertransfusion. Further research regarding the issue of undertransfusion is warranted and could be expanded to include other components.     

Treatment of Felty's syndrome with the haemopoietic growth factor granulocyte colony-stimulating factor (G-CSF)

Felty's syndrome (FS) (rheumatoid arthritis with neutropenia and splenomegaly) has a poor prognosis, largely because of the high risk of severe infection. Granulocyte colony-stimulating factor (G-CSF) is an emerging treatment for chronic neutropenia. We prospectively monitored its use in eight patients with recurrent infections or who required joint surgery. Significant side-effects were documented in five, including nausea, malaise, generalized joint pains, and in one patient, a vasculitic skin rash. In two patients treatment had to be stopped, and in these cases G-CSF had been started at full vial dosage (300 micrograms/ml filgrastim or 263 micrograms/ml lenograstim) alternate days or daily. G-CSF treatment was continued in three patients by restarting at reduced dose, and changing the proprietary formulation. G- CSF raised the neutrophil count, reduced severe infection, and allowed surgery to be performed. A combined clinical and laboratory index suggested that long-term treatment (up to 3.5 years) did not exacerbate the arthritis. Once on established treatment, it may be possible to use smaller weekly doses of G-CSF to maintain the same clinical benefit. One of the three patients whose FS was associated with a large granular T-cell lymphocytosis showed a reduction in this subset of lymphocytes during G-CSF treatment.