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41.

Objective

The purpose of this study was to investigate the differences between spinal metastasis and osteoporotic compression fractures on plain X-ray images, focusing on asymmetrical vertebral collapse and fracture level.

Materials and methods

This study included 180 patients with pathological collapse from spinal metastasis (188 vertebrae) who were treated at our institution and 70 patients (92 vertebrae) with osteoporotic compression fractures. Anteroposterior X-ray images of the lower thoracic and lumbar spine were evaluated for asymmetrical collapse deformity.

Results

Asymmetrical collapse was found in 134 vertebrae (71.3%) with metastasis, and in 20 osteoporotic vertebrae (21.7%); this difference was significant (p < 0.0001). The asymmetrical collapse angle in spinal metastasis patients ranged from 0 to 18°, with a mean of 7.0 and a standard deviation (SD) of 4.5. In contrast, the asymmetrical collapse angle in patients with osteoporotic fractures ranged from 0 to 13°, with a mean of 3.1 and a SD of 2.8. The difference in collapse angle between the two groups was statistically significant (p < 0.001). The cutoff value to suspect spinal metastasis was determined to be 5° or more (sensitivity 0.67, specificity 0.74). Fracture at Th10 or below L3 was found in 20.2% of spinal metastasis patients; only 3% of osteoporotic fractures occurred at these levels.

Conclusion

Asymmetrical collapse with an angle of 5° or more and fractures at atypical levels on plain radiographs can be useful clues to spinal metastasis.  相似文献   
42.

Purpose

To clarify the risk factors for complications after diverting ileostomy closure in patients who have undergone rectal cancer surgery.

Methods

The study group comprised 240 patients who underwent a diverting ileostomy at the time of lower anterior resection or internal anal sphincter resection, in our department, between 2004 and 2015. Univariate and multivariate analyses of 18 variables were performed to establish which of these are risk factors for postoperative complications.

Results

The most common complications were intestinal obstruction and wound infection. Univariate analysis showed that an age of 72 years or older (p?=?0.0028), an interval between surgery and closure of 6 months or longer (p?=?0.0049), and an operation time of 145 min or longer (p?=?0.0293) were significant risk factors for postoperative complications. Multivariate analysis showed that age (odds ratio, 3.4236; p?=?0.0025), the interval between surgery and closure (odds ratio, 3.4780; p?=?0.0039), and operation time (odds 2.5179; p?=?0.0260) were independent risk factors.

Conclusions

Age, interval between surgery and closure, and operation time were independent risk factors for postoperative complications after diverting ileostomy closure. Thus, temporary ileostomy closure should be performed within 6 months after surgery for rectal cancer.
  相似文献   
43.
Encapsulated hepatocyte transplantation is a promising approach to cell transplantation without immunosuppression as an alternative to whole organ liver transplantation. However, the shortage of donor cells for hepatocyte transplantation has not been resolved, and at this critical point, it seems necessary to establish a method of hepatocyte cryopreservation to allow clinical application of hepatocyte transplantation and the development of a bioartificial liver system in the near future. In this study we demonstrated that cryopreserved microencapsulated rat and human hepatocytes can retain their hepatic function and that cryopreserved microencapsulated human hepatocytes transplanted into rat spleen remain viable without immunosuppression. Rat and human hepatocytes were isolated by a collagenase digestion method, and they were microencapsulated with poly-L-lysine. The microencapsulated rat hepatocytes were transferred to culture medium (DMEM containing 10% FBS and 10% DMSO) and immediately frozen in liquid nitrogen. A warm water bath (37 degrees C) was used to thaw the microencapsulated hepatocytes. Hepatic function, drug metabolism, and cell morphology were assessed after 90 days of cryopreservation. After 1 week of cryopreservation, microencapsulated hepatocytes were cultured for up to 2 weeks to assess their hepatic function and morphology. The morphology of human hepatocytes was assessed after 30 days of cryopreservation. Cryopreserved human hepatocytes were transplanted into rat spleen to assess their morphology. Cryopreserved microencapsulated hepatocytes retained their viability and were strongly positive for expression of albumin, OAT2, CYP3A2, and CYP3A9. Two weeks after cultivation, the cryopreserved microencapsulated rat hepatocytes had retained their hepatic function (urea synthesis). Cryopreserved microencapsulated human hepatocytes also mainly survived and retained their hepatic function for at least 30 days after cryopreservation. Moreover, entrapped cryopreserved human hepatocytes also survived and expressed albumin in rat spleen after transplantation. We demonstrated a novel method of long-term cryopreservation of rat and human hepatocytes by using an encapsulation technique, with retention of biological activity and excellent survival of the cryopreserved microencapsulated human hepatocytes transplanted into rat spleen. We believe that this novel approach to hepatocytes cryopreservation provides a new direction in encapsulated cell therapy with the goal of clinical application in the near future.  相似文献   
44.
45.
46.

Introduction

Because the donor shortage is extremely severe in Japan because of a strict organ transplantation law, special strategies must be established to maximize heart transplantation (HTx) and lung transplantation (LTx) opportunities. The purpose of this study was to review our strategies to identify and manage heart and lung donors.

Method

Transplantation doctors themselves assessed their own donor heart and lung function before starting the procurement operation; skillful staff surgeons harvested the organs. Since November 2002, a special transplantation consultant doctor assessed donor organ function to identify useful organs and intensively cared for the donor to improve cardiac and lung function.

Results

Only 63 brain-dead donors have been available in Japan. However, 49 HTx (77.7%) and 39 LTx (19 bilateral and 20 single) were performed from 36 donors (57.1%). Thirty-six HTx donors were marginal, requring sustained high doses of inotropes (n = 26), low left ventricular ejection fraction (n = 5), cardiopulmonary resuscitation (n = 15), and age older than 55 years (n = 6). Twenty LTx donors had infected sputa or showed pneumonia using chest X-ray. None of 49 HTx recipients died of primary graft failure (PGF). Patient survival at 3 years after HTx was 98.0%. Although 5/39 LTx died early, including 2 of PGF, patient survival rate at 3 years was 66.9%.

Conclusion

Although the number of cases was still small, the availability of hearts and lungs has been high and the transplantation outcomes were acceptable. These strategies may be useful to maximize HTx/LTx opportunities.  相似文献   
47.
We present a case of lung cancer that showed false positive accumulation in an 18F fluorodeoxyglucose positron emission tomography (FDG-PET) scan following induction chemotherapy for suspected metastasis and progression of malignancy. A 66-year-old man was diagnosed with squamous cell carcinoma in the lung, classified as clinical stage IIIA (T2N2M0), and underwent induction chemotherapy. An FDG-PET scan prior to chemotherapy demonstrated accumulation only in the tumor, whereas following treatment it revealed a strong accumulation not only in the tumor, but also in the supraclavicular lymph nodes, which indicated lymph node metastasis. The patient underwent a biopsy of the right supraclavicular lymph node and mediastinoscopy, after which all dissected lymph nodes showed sarcoid reactions and no tumor cells were found pathologically. We concluded that when evaluating the effect of induction chemotherapy for malignancy, a sarcoid reaction might lead to the false positive accumulation of FDG.  相似文献   
48.
The aim of this study was to assess the radiologic and clinical outcome when beta-tricalcium phosphate is used as a bone graft substitute to backfill the fibular defect that is created by harvesting the fibula. Fourteen patients who had fibula resections to be used as bone grafts for bone tumor resections were assessed radiographically. Callus formation bridging the beta-tricalcium phosphate was seen in 12 of 14 patients at an average of 1.4 months after surgery. In these 12 patients the beta-tricalcium phosphate mostly was absorbed and replaced by newly formed bone at an average of 9.3 months after surgery. In all children, beta-tricalcium phosphate was replaced by newly formed bone at an average of 3.2 months after surgery. Only one adult patient had complete regeneration of the fibula. Few patients had continuity between the regenerated fibula and the native fibula. In one patient in whom free vascularized fibula was harvested, regeneration of the fibula was not observed. Clinical functional outcome was not correlated with successful fibula regeneration and union with the native fibula, as determined using radiographs. The results of the study suggest that, in children, regeneration of the fibula by implanting beta-tricalcium phosphate into a bone defect can reduce morbidity of the fibula harvest sites.  相似文献   
49.
Programmed death ligand 1 (PD-L1) is a key target for the treatment of several malignancies. The present study was conducted to clarify the role of serum PD-L1 in hepatocellular carcinoma (HCC). Serum PD-L1 (sPD-L1) was examined by an enzyme-linked immunosorbent assay in 153 patients with HCC who underwent curative hepatectomy at Kumamoto University in 2011–2016. The expression of PD-L1 in tissue (tPD-L1) was investigated by immunohistochemistry. The clinical roles of the PD-L1 expression in both serum and tissue were examined. The sPD-L1 was significantly elevated in HCC patients compared to patients without any malignant or inflammatory disease (234 vs. 93 pg/mL, p < 0.0001). The percentage of the tPD-L1-positive area (%tPD-L1) in the background liver was significantly higher than in the tumor (1.52% vs. 0.48%, p < 0.0001). The %tPD-L1 in the background liver but not in the tumor was significantly correlated with the sPD-L1 level (p = 0.0079). The sPD-L1, %tPD-L1 in the tumor, and %tPD-L1 in the background liver were not correlated with the overall survival after surgery. PD-L1-expressing cells in the background liver, but not in the tumor tissue, appeared to contribute to the sPD-L1 level. The sPD-L1 level may thus not indicate the tumor burden in patients with HCC.  相似文献   
50.
Two cases of nonfunctioning adrenocortical adenoma are herein reported. The adrenal tumor was found incidentally by computed tomography in both patients. Preoperative evaluation revealed that both patients had neither abnormal values in a variety of adrenal function studies nor any recognizable clinical signs associated with adrenal tumor. Following a definitive diagnosis of nonfunctioning adrenal tumors, surgical extirpation was performed in both cases. Histopathological finding was adrenocortical adenoma. Nonfunctioning adrenocortical tumor will be found more frequently with the increasing use of computed tomography in ordinary clinical practice. The management of nonfunctioning adrenocortical tumor is briefly discussed.  相似文献   
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