Comparison of different methods of spatial normalization of FDG-PET brain images in the voxel-wise analysis of MCI patients and controls

Objective

One of the most interesting clinical applications of 18F-FDG PET imaging in neurodegenerative pathologies is that of establishing the prognosis of patients with mild cognitive impairment (MCI), some of whom have a high risk of progressing to Alzheimer’s disease (AD). One method of analyzing these images is to perform statistical parametric mapping (SPM) analysis. Spatial normalization is a critical step in such an analysis. The purpose of this study was to assess the effect of using different methods of spatial normalization on the results of SPM analysis of 18F-FDG PET images by comparing patients with MCI and controls.

Methods

We evaluated the results of three spatial normalization methods in an SPM analysis by comparing patients diagnosed with MCI with a group of control subjects. We tested three methods of spatial normalization: MRI-DARTEL and MRI-SPM8, which combine structural and functional images, and FDG-SPM8, which is based on the functional images only.

Results

The results obtained with the three methods were consistent in terms of the main pattern of functional alterations detected; namely, a bilateral reduction in glucose metabolism in the frontal and parietal cortices in the patient group. However, MRI-SPM8 also revealed differences in the left temporal cortex, and MRI-DARTEL revealed further differences in the left temporal cortex, precuneus, and left posterior cingulate.

Conclusions

The results obtained with MRI-DARTEL were the most consistent with the pattern of changes in AD. When we compared our observations with those of previous reports, MRI-SPM8 and FDG-SPM8 seemed to show an incomplete pattern. Our results suggest that basing the spatial normalization method on functional images only can considerably impair the results of SPM analysis of 18F-FDG PET studies.     

胫骨下端恶性骨肿瘤切除后大段异体骨重建

目的应用大段异体骨移植及踝关节融合的保肢方法治疗胫骨下端恶性肿瘤和侵袭性肿瘤，并从预后、术后并发症及功能等几个方面加以评价。方法自1998年1月至2005年12月应用大段异体骨移植及踝关节融合的保肢方法治疗胫骨下端肿瘤患者11例；包括骨肉瘤8例，骨巨细胞瘤2例，软骨肉瘤1例。对骨肉瘤患者行新辅助化疗，按照Enneking分期，手术行边缘切除或广泛切除，应用大段深低温冷冻保存同种异体骨重建，钢板螺钉或带锁髓内钉固定。结果术后随访18-78个月，平均47个月。其中8例骨肉瘤患者随访28-78个月，平均50个月。11例均获得良好的骨愈合，开始出现骨愈合时间为术后3-18个月，平均8个月。无异体骨反应继发感染，无内固定失败。异体骨骨折1例，复发2例，肺转移3例，保肢率为81．8％。术后功能评定采用骨骼肌肉系统肿瘤手术治疗后重建功能评估系统（MSTS系统），评分为16～27分，平均24-3分。结论胫骨下端虽然软组织覆盖较薄，血运相对较差，但保肢术后肿瘤复发率不高，异体骨感染、不愈合、骨折率较低。固定方式以髓内固定为佳。大段异体骨移植及踝关节融合的保肢方法术后功能良好，给患者带来较大的心理安慰，是一种较好的保肢方式。     

丹参素对成纤维细胞生物学作用机制的研究

目的　探讨丹参素对成纤维细胞凋亡和前胶原基因表达的影响。　方法　于培养的人皮肤成纤维细胞（2×10     

Clinical Variables Associated With the Presence of Inflammatory Infiltrates in Patients With Dilated Cardiomyopathy Undergoing Heart Transplantation

Introduction

Idiopathic dilated cardiomyopathy (DCM) is, together with ischemic heart disease, the major cause of end-stage heart failure leading to heart transplantation. However, an unknown percentage of patients with this diagnosis has inflammatory foci found in the histopathological study of the explanted heart. This fact suggests an undetected process of acute myocarditis as the cause of cardiac dysfunction.

Objective

The objective of this study was to identify clinical and echocardiographic variables related to the presence of myocardial infiltrates, as a potential guide to determine which patients should undergo endomyocardial biopsy in DCM.

Materials and Methods

We retrospectively analyzed 161 patients who underwent heart transplantation with a diagnosis of DCM between 1987 and 2007. The presence of inflammatory infiltrates was considered significant when the histopathological study of tissue blocks from the left ventricle showed 1 or more foci per cm² of perivascular or interstitial mononuclear or polymorphonuclear cells, whether or not in the presence of cytolysis.

Results

Seventeen patients (11%) had these inflammatory histological findings; of them, 6 (35%) showed preponderance of eosinophils and 7 (41%) showed areas of cytolysis. The DCM group with inflammatory infiltrates showed significant differences in terms of younger age (45 ± 15 vs 50 ± 11 years; P < .01) and smaller ventricular diameters (P < .05). Male gender was more frequent in this group, and the patients had a poorer clinical status and greater dependence on inotropic drugs.

Conclusions

Inflammatory infiltrates are frequently present in DCM explanted hearts. Although there are no relevant clinical variables to identify subclinical myocarditis, these patients are younger and have smaller ventricular diameters and poorer functional status at the time of transplantation.     

肠系膜血管病变引起的急腹症八例报告

目的：全面认识肠系膜血管病变引起的急腹症的严重性，提高疗效。方法：对8例临床特点、治疗方法和效果进行了分析比较。结果：6例经手术病理证实，初诊多表现为急腹症，症状和体征不相符，5例误诊，1例术前确诊，2例肠系膜血管供血不足经CT及腹腔动脉造影明确诊断并经药物治疗，7例治愈，1例死亡。结论：该病较少见，症状和体征无特异性，难以做出准确的诊断，B超和CT是较敏感的检查，对诊断有积极的作用。早期切除坏死肠段，包括静脉阻塞的肠系膜部分，术中和术后抗凝治疗是预防复发、降低病死率的重要措施。     

Assay of cytomegalovirus susceptibility to ganciclovir in renal and heart transplant recipients

Ganciclovir (GCV) prophylaxis or pre-emptive therapy significantly reduce the rate of cytomegalovirus (CMV) disease and viremia, but increase the potential for emergence of ganciclovir-resistant CMV strains. The inhibitor concentration at 50% (IC(50)) of GCV from 156 CMV isolates from 59 renal or heart transplant recipients was calculated by means of a rapid phenotypic susceptibility assay. Twenty-seven strains were from 14 patients undergoing GCV therapy. The IC(50) was higher in patients under the prophylaxis regimen. One CMV strain, from a heart transplant recipient, became GCV-resistant after 1 month of therapy (IC(50)=13.7 micromol/l). These data, together with clinical and virological markers, suggested that a switch to foscarnet was necessary, and good evolution was observed. Thus, assay of CMV susceptibility to GCV could be helpful in clinical management.     

Evaluation of bone height and bone density after tooth extraction: an experimental study in minipigs.

OBJECTIVE: The objective of this study was to radiographically quantify bone density and bone height preservation in tooth extraction alveolus filled with xenograft. STUDY DESIGN: The maxillary and mandibular fourth deciduous molars and fourth premolars of 6 minipigs were removed. Randomly, in 3 animals the right side was used as the test side and in the other 3 animals the left side was the test side. Intraoral radiographs were performed to compare the condition at the initial time and 3 months later. Measurements of bone height and bone density were performed using KS300 (Zeiss) software. RESULTS: After 3 months, there was a statistically significant smaller bone height loss for the test group. The test group presented a statistically greater bone density immediately after tooth extraction. However, after 3 months there was no statistically significant difference between the groups. CONCLUSIONS: The results suggest that treatment of postextraction alveolus with xenograft can preserve bone height initially but differences in bone density compared to when no xenograft is used are not sustained.     

Curative Laparoscopic Resection for Pancreatic Neoplasms: A Critical Analysis from a Single Institution

Laparoscopic pancreatic surgery (LPS) has seen significant development but much of the knowledge refers to small and benign pancreatic tumors. This study aims to evaluate the feasibility, safety, and long-term outcome of the laparoscopic approach in patients with benign, premalignant, and overt malignant lesions of the pancreas. This study, currently, is the largest single center experience worldwide. One hundred twenty-three consecutive patients underwent laparoscopic pancreatic surgery from April 1998 to April 2007, 20 patients with cysts or pseudocysts for acute and chronic pancreatitis, laparoscopic pancreatic drainage was performed, and were excluded from the analysis. The 103 patients were divided based on preoperative diagnosis: group I, inflammatory tumors for chronic pancreatitis (eight patients); group II, cystic pancreatic neoplasms (29 patients); group III, intraductal papillary mucinous neoplasms (10 patients); group IV, neuroendocrine pancreatic tumors (NETs) (43 patients); and group V ductal adenocarcinoma (13 patients). The median tumor size was 5.3 cm. Pathologic data include R ₀ or R ₁ resection (transection margins on the specimen were inked). Perioperative data, postoperative complications, and resection modalities were compared using statistical analysis. Long-term outcomes were analysed by tumor recurrence and patient survival. The overall conversion rate was 7%. Laparoscopic distal pancreatic resection was performed in 82 patients (79.6%). Laparoscopic spleen-preserving distal pancreatectomy (Lap SPDP) was performed in 52 patients (63.7%), but with splenic vessels preservation in 22% and without splenic vessels preservation in 41.5%. Laparoscopic en-bloc splenopancreatectomy (Lap SxDP) was performed in 30 patients (36.6%) and laparoscopic enucleation (Lap En) in 20 patients (19.4%). There was no mortality. The overall complication rate was 25.2, 16.7, and 40% after Lap SPDP, Lap SxDP, and Lap En, respectively. The overall morbidity rate was significantly higher (p > 0.05) in the group of Lap SPDP without splenic vessels preservation comparing with Lap SPDP with splenic vessels preservation because of the occurrence of splenic complications (20.6%). The overall pancreatic fistulas was 7.7, 10, and 35% after Lap SPDP, Lap SxDP, and Lap En, respectively; the severity of fistula was significantly higher in the Lap En group (p > 0.05). The mean hospital stay was within 1 week in all groups, except in the group of ductal adenocarcinoma, which is 8 days. In this series, 27 patients (26.2%) had malignant disease. R ₀ resection was achieved in 90% of ductal adenocarcinoma and 100% for other malignant tumors. The median survival for ductal adenocarcinoma patients was 14 months. This series demonstrates that LPS is feasible and safe in benign-appearing and malignant lesions of the pancreas.     

Versatility of the pedicled thoracodorsal artery perforator (TDAP) flap in soft tissue reconstruction

For the last decades, the latissimus dorsi skin-muscle flap has contributed to the efficient reconstruction of the loss of skin cover (especially in breast surgery) and in long-distance tissue defects. Unfortunately, the nonuse of such an important muscle as the latissimus dorsi for the patient, as well as the resulting thickness of the flap after reconstruction, has turned it into a second choice flap. However, this flap is still indicated in the reconstruction of areas which need a great amount of cutaneous and muscular tissue. The appearance of the perforator flaps and, specifically, thoracodorsal artery perforator (TDAP) flap, has meant a radical change in relation to lower morbidity of the donor site, thus highly ranking the use of these flaps in the reconstruction for similar defects. The aim of this publication is to present our experience with the pedicled TDAP flap in a series of 17 different cases. Of those, there were 14 cases of mammary reconstruction after sparing surgery, 2 cases of axillary reconstruction following severe recurrent hidradenitis, and a case of extensive substance loss in a patient's upper limb following a severe crush injury.     

Requirement and postoperative outcomes of abdominal panniculectomy alone or in combination with other procedures in a bariatric surgery unit

Background

A high percentage of patients present with redundant skin folds after bariatric surgery. This study aims to quantify the need for panniculectomy after open bariatric surgery and to analyze the postoperative outcomes.

Methods

A retrospective cohort study was performed. The patients were divided into 2 groups: group DLP, patients who underwent an abdominal panniculectomy alone and group DLP+, those who underwent panniculectomy in association with another surgical procedure.

Results

Four hundred forty-six patients underwent open bariatric surgery and 130 patients (29%) subsequently required an abdominal dermolipectomy. Seventy-six percent presented also incisional hernia and 8% presented cholelithiasis. Forty-six percent of patients presented postoperative complications: wound seroma/infection (21%), wound dehiscence due to skin necrosis (13%), and hemorrhage/hematoma (10%) were the most frequent. There were no major complications or mortality. DLP+ was not associated with an increase in complications.

Conclusions

After open bariatric surgery, an abdominal panniculectomy is often required. This procedure has a high postoperative morbidity in these patients, although complications are usually mild. There is not an increase in the rate of complications when panniculectomy is associated with other procedures.