Pediatric empyema--an algorithm for early thoracoscopic intervention.

INTRODUCTION: The management of pediatric empyema remains controversial. We contend that early thoracoscopic intervention results in shorter hospital stays, decreased morbidity, and superior outcomes. We propose an algorithm using early image-guided thoracoscopy as an effective treatment for pediatric empyema. METHODS: Consecutive pediatric empyemas treated from November 1997 to April 2001 using a prospective management algorithm were reviewed. Demographic data, days to diagnosis, days to surgery, length of stay, chest tube days, complications, and follow-up were recorded. RESULTS: Twenty-two children with 24 empyemas were treated using this algorithm. Their mean age was 49 months. Mean days to diagnosis was 11 and from diagnosis to surgery was 3. Imaging included chest radiography (CXR) in all, ultrasound in 17 (77%), and computed tomography (CT) scan in 13 (59%). One thoracoscopy was converted to a mini-thoracotomy because of difficulty with ventilation. Chest tube removal averaged 3 days with an average length of stay of 13 days. One patient required a second thoracoscopy for recurrent empyema, and 1 patient developed a contralateral empyema. No other complications or deaths occurred. Follow-up in 19 of 22 (86%) children at 5 months revealed no recurrences or mortality. CONCLUSION: This treatment algorithm, using early image-guided thoracoscopy, is a safe and effective means of managing pediatric empyema, while shortening hospital stay and avoiding the morbidity of thoracotomy.     

Management of saddle nose deformity in atrophic rhinitis

Correction of a saddle nose deformity due to atrophic rhinitis is a formidable task. The thick and puckered skin secondary to long standing disease makes the creation of a dorsal subdermal pocket difficult. On the one hand, these patients tolerate synthetic implants poorly and on the other they show an unusually high rate of absorption of autologous bone graft. Our experience of treating 15 patients with saddle nose deformity secondary to atrophic rhinitis is presented.     

Usefulness of intravascular ultrasound in preventing stenting of hazy areas adjacent to coronary stents and its support of support spot-stenting

The uncertain significance of hazy areas at the margins of coronary stents may lead to further, at times unnecessary, stenting. However, the risk of restenosis increases substantially when additional stents are deployed. We used intravascular ultrasound (IVUS) to identify the causes of hazy segments adjacent to stents. We identified 13 cases with hazy regions adjacent to coronary stents and 20 controls without hazy regions matched by age, gender, and vessel stented. Hazy regions were defined from the angiogram as reduced contrast density without a clearly defined intimal tear, dissection, thrombus, or stenosis (> 50%). IVUS images were obtained from the reference, stent, and hazy and control regions adjacent to the stent. Computerized planimetery was used to measure the vessel, lumen, and plaque cross-sectional areas (CSAs), the maximum arc of calcium, and the eccentricity ratio (minimum:maximum lumen diameter). There were no significant differences between hazy and control segments in the vessel, lumen, and plaque CSAs. All lumen CSAs were >4.0 mm2. Compared with control regions, the hazy regions had calcified plaque more often (69% vs 25%; odds ratio [OR] 6.75, 95% confidence intervals [CI] 1.82 to 25.0]) and more frequent intimal tears (23% vs 0%, OR 6.67, 95% CI 1.98 to 35.0). Haziness was particularly associated with calcified plaque and eccentric lumen (p = 0.037). Thus, haziness at the margins of coronary stents is often caused by calcified plaque. IVUS can differentiate calcified plaques from intimal tears and thereby obviate unnecessary stenting.     

Patterns of cytomegalovirus infection in simultaneous kidney–pancreas transplant recipients receiving tacrolimus, mycophenolate mofetil, and prednisone with ganciclovir prophylaxis

Abstract: Background: The impact of tacrolimus (TAC), mycophenolate mofetil (MMF) and steroid immunosuppression on cytomegalovirus (CMV) infection in combination with ganciclovir prophylaxis in simultaneous kidney–pancreas transplantation (SKPT) has not been well studied. Methods: A retrospective analysis was made of 75 SKPTs performed between 1 January 1996 and 7 January 1999. All patients received ganciclovir for 3 months, but CMV donor (D)+/ recipient (R)? patients received ganciclovir for 6 months. Results: 16/74 (22%) were CMV D+/R?, 25 (33%) D+/R+, 16 (22%) D?/R+, and 17 (23%) D?/R? (1 patient with unknown donor serology was excluded). The mean time to CMV infection was 198 days post‐transplant. The incidence of either CMV infection or tissue invasive CMV disease was 16/74 (22%), including 9 (12%) with CMV infection and 7 (10%) CMV disease. The one‐year patient, kidney, and pancreas graft survival rates were 91%, 89%, and 83%, respectively. The mean follow‐up was 29 months (minimum of 12 months). CMV infection was not associated with an increased incidence of graft failure or mortality. The D+/R? group had the highest incidence of CMV infection (44%) compared with the other serologic groups (17%, P=0.02). Concurrent CMV and rejection occurred more frequently in the D+/R? than the other serologic groups (25% vs. 7%, P=0.03). The D?/R? group had the best outcomes, with no CMV infection, improved kidney graft survival at the end of follow‐up (82% vs. 72%, P=0.04) and the highest event‐free survival (no CMV infection, rejection, or graft loss) when compared to the other groups (76% vs. 33%, P<0.01). Conclusions: Compared to previous studies, ganciclovir prophylaxis delayed the onset and reduced the severity of CMV infection in patients receiving TAC, MMF, and steroids. Despite ganciclovir prophylaxis, CMV seronegative patients receiving CMV D+ organs had worse outcomes than seronegative recipients receiving CMV D? organs.     

Isolation of intestinal spirochaetes from homosexuals

Spirochaetes were isolated from rectal swabs of two homosexuals and the faeces of a third, using simple isolation techniques not previously applied to specimens of this type. The ease of culture of these organisms will enable their distribution and pathogenicity to be studied, particularly in relation to their significance in homosexuals.     

心房颤动的电生理重构

心房颤动 (atrial fibrillation,AF)是临床上最常见的一种持续性心律失常 ,其发病率随年龄而增加 ,40岁以下人群发病率约为 0 .2 %～ 0 .3% ,6 0～ 90岁年龄组发病率增至5 %～ 9% [1 ] 。新近 Framingham的研究表明 AF可以成为一种独立的因素使患者病死率增加 [2 ] 。 AF的发病机制尚未完全清楚 ,可能为非单一机制 ,普遍认为持续性 AF是由于心房内的多子波折返 ,每 1个折返环本身都在不停地改变其大小及传导方向。近年来 ,在 AF的基础及临床研究中 ,两个方面的进展具有十分重要的意义 :一是发现部分 AF起源于心房内某些部位如肺静脉口…     

长期运动对十二指肠黏膜一氧化氮合成和铁贮存的调控效应

目的:观察长期运动对十二指肠黏膜一氧化氮合成和铁贮存的影响及一氧化氮对铁贮存的调节作用。方法:实验于2004-04/09在江苏大学医学院铁代谢研究室完成。①健康雌性SD大鼠40只,随机分为静息组、静息并应用一氧化氮抑制剂组、运动组、运动并应用一氧化氮抑制剂组,每组10只。②静息并应用一氧化氮抑制剂组和运动并应用一氧化氮抑制剂组饮用水中含有一氧化氮抑制剂(1g/L),运动组和运动并应用一氧化氮抑制剂组的大鼠游泳3个月。③3个月后分析各组大鼠血浆铁饱和度,一氧化氮浓度以及十二指肠黏膜一氧化氮含量和非血红素铁含量。结果:实验过程中死亡11只,进入结果分析29只(静息组8只、静息并应用一氧化氮抑制剂组5只、运动组8只、运动并应用一氧化氮抑制剂组8只)。①运动及一氧化氮抑制剂对大鼠血浆铁饱和度和一氧化氮浓度的影响:运动组的血浆铁饱和度低于静息组(P<0.01);运动并应用一氧化氮抑制剂组的血浆铁饱和度低于静息并应用一氧化氮抑制剂组(P<0.05),并且高于运动组(P<0.05)。运动组血浆一氧化氮浓度显著高于静息组(P<0.01);运动并应用一氧化氮抑制剂组的血浆一氧化氮浓度低于运动组(P<0.01),与静息并应用一氧化氮抑制剂组差别不显著(P>0.05)。②运动及一氧化氮抑制剂对大鼠十二指肠黏膜一氧化氮和非血红素铁含量的影响:运动组的十二指肠一氧化氮含量高于静息组(P<0.01);静息并应用一氧化氮抑制剂组的一氧化氮含量低于静息组(P<0.01);运动并应用一氧化氮抑制剂组的一氧化氮含量低于运动组(P<0.01),但高于静息并应用一氧化氮抑制剂组(P<0.01),与静息组差别不显著。与静息组比较,运动组和静息并应用一氧化氮抑制剂组的十二指肠黏膜非血红素铁含量均降低(P<0.05)。结论:静息状态下十二指肠黏膜细胞一氧化氮合成具有较高的紧张性,可能参与维持非血红素铁含量。长期运动可刺激十二指肠黏膜一氧化氮合成,降低铁贮存。但其机制是否涉及运动诱导的一氧化氮的直接作用以及是否参与铁吸收的调节有待于进一步研究。     

Spontaneous Coronary Artery Dissection Associated With β-HCG Injections and Fibromuscular Dysplasia

Spontaneous coronary artery dissection (SCAD) is an infrequent cause of acute coronary syndrome predominantly affecting younger women. SCAD is often associated with predisposing arterial abnormalities and precipitating emotional, physical, and hormonal stressors. We previously showed that fibromuscular dysplasia is strongly associated with SCAD and may be a causative factor. Hormonal changes related to pregnancy and sex hormones have also been shown to be an important cause of SCAD. We describe the first case report, to our knowledge, of SCAD associated with β-human growth hormone injections in a patient with concomitant FMD.     

Hindrance of binding to class II major histocompatibility complex molecules by a single amino acid residue contiguous to a determinant leads to crypticity of the determinant as well as lack of response to the protein antigen.

The immune system has evolved the potential to respond to a wide variety of antigens, yet unresponsiveness to many foreign determinants is encountered frequently. Here, we report a lack of response to a particular determinant, hen egg lysozyme (HEL)-(46-61)-peptide (p46-61), in C57BL/6 (H-2b) mice, whereas a strong T-cell response to this determinant is obtained in major histocompatibility complex (MHC)-identical C3H.SW mice. However, (C3H.SW x C57BL/6)F1 mice respond well to p46-61, suggesting the absence of a p46-61-specific "hole" in the T-cell repertoire in C57BL/6 mice. We further show that p46-61 cannot bind the I-Ab class II MHC molecule, whereas p46-60 lacking Arg61 exhibits good binding and is immunogenic in both strains. Thus, the presence of the hindering residue, Arg61, renders p46-61, a dominant determinant in C3H.SW, into a silent, cryptic determinant in C57BL/6 mice. Upon i.p. immunization with HEL, no T-cell responses to either HEL or p46-61 could be demonstrated in spleens of HEL-primed C57BL/6 mice, whereas a predominant response to p46-61 and HEL was demonstrated in C3H.SW mice. Evidently, C57BL/6 mice differ from C3H.SW in their ability to process p46-61 into an actual I-Ab binding determinant, indicating a putative enzymatic defect in the C57BL/6 strain. Furthermore, our results suggest that the inability of C57BL/6 mice to respond in the spleen to HEL is based upon its failure to generate a dominant immunogenic determinant from HEL, coupled with its pattern of susceptibility to regulatory effects.