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91.

Purpose

It is still controversial whether simultaneous or staged total knee arthroplasty (TKA) is most desirable for patients with bilateral knee osteoarthritis. We retrospectively evaluated changes in balance among patients with bilateral osteoarthritis who underwent staged TKA using a gravicorder.

Methods

Patients were stratified into two groups: the unilateral group (UG) (22 patients) consisted of patients who did not undergo a second TKA within 24 months of the first TKA, and the bilateral group (BG) (20 patients) were those who had a second TKA within 12 months after initial TKA.

Results

The mean gravity center position (GCP), which indicates the translation of GCP in the mediolateral direction between pre- and post-TKA shifted to the operative side in both groups after initial surgery. While the GCP was maintained on the same side in UG over 2 years follow-up, in BG it moved to the opposite side and approached a central position after the second TKA. Locus length of GCP (LG), which indicates postural control function by proprioceptive reflex showed significant improvement after initial TKA in UG, while BG showed significant improvement after the second TKA.

Conclusions

The degree of LG improvement after initial TKA may indicate the necessity of a second TKA for patients with bilateral osteoarthritis. The current study suggests that simultaneous bilateral TKA is not always necessary for patients with bilateral knee arthritis, and that properly performed rehabilitation such as improving postural sway after initial TKA might attenuate the timing for the second TKA.  相似文献   
92.
Serum free-beta human chorionic gonadotropin (fbhCG) has been used for the diagnosis and management of testicular tumors for many years in Japan, while the measurement of serum hCG is widely used in the world. There have been reports of false-positive cases with serum fbhCG and due care must be taken in order not to take the wrong treatment strategy. Serum hCG is said to be more useful in the diagnosis and management of non-seminoma than serum fbhGC. Because of the false-positive issue with serum fbhCG, however, we consider it appropriate to use serum hCG for measurement even in seminoma. We simultaneously measured serum hCG and serum fbhCG in 25 cases of seminoma in order to evaluate the usefulness of hCG assay in the diagnosis and management of seminoma. In the measurements, we found 5 false-positive cases (20%) with serum fbhCG. The diagnostic sensitivity of the 20 cases with the exception of the 5 false-positive cases was 16 cases (80%) and 14 cases (70%) with serum hCG and serum fbhCG, respectively. We conclude that serum hCG is more reliable and is a useful assay in the diagnosis and management of seminoma, but serum fbhCG is not useful in the diagnosis and management of testicular tumor and its independent measurement should not be used to avoid misleading results.  相似文献   
93.
Porcine islets are considered to be a promising resource for xenotransplantation. However, it is difficult to isolate porcine islets because of the marked fragility and rapid dissociation. Endogenous trypsin is one of the main factors to damage islets during the isolation procedure. Recent studies have suggested that trypsin inhibitors during the preservation of pancreas or the collagenase digestion can improve the result of islet isolation. In this study, we examined whether α1-antitrypsin (Aralast?), which inhibits several endogenous proteases and has immunomodulatory properties, can protect islets from the proteases and improve the results of porcine islet isolation. Twelve porcine pancreata were divided into three groups: without Aralast group (standard, n = 5), preserved with Aralast using the ductal injection (DI) method (DI, n = 3), and with Aralast using the DI method and in the collagenase solution (DI+C, n = 4). Efficacy of islet isolation was assessed by islet yields, purity, and viability. The trypsin activity of the preservation and the digestion solution during the isolation procedure was measured. During islet isolation, the trypsin activity in DI+C group was significantly inhibited compared to the standard group, whereas DI group showed less effect than DI+C group. The average of postpurification islet equivalents (IEQ) per pancreas weight in the DI+C group was significantly higher than the standard group (standard: 3516 ± 497 IEQ/g, DI: 4607 ± 1090 IEQ/g, DI+C: 7097 ± 995 IEQ/g; p = 0.017 between standard and DI+C). In the DI+C group, stimulation index was higher than in other groups, although there was no significant difference. The presence of Aralast in both DI solution and collagenase solution markedly inhibited trypsin activity during pancreas digestion procedure and improved the porcine islet isolation. Inhibition of trypsin activity by Aralast could improve porcine islet isolation.  相似文献   
94.
Porcine islets are a promising resource for xenotransplantation. However, low efficacy of islet isolation because of their marked fragility remains a problem. Recently we found that the standard purification method using COBE 2991 cell processor (COBE) with Ficoll density gradient solution damaged islets mechanically by high shearing force. In this study, we evaluated our new purification method using large plastic bottles for the efficacy of islet purification. Ten porcine pancreata were used. The average warm ischemic time was over 40 min; therefore, these pancreata were considered to be in a marginal condition. After digestion, the digested tissue was divided into three groups. Each group was purified using either top loading method with bottle (top group) or bottom loading method with bottle (bottom group) or standard COBE method (COBE group). Islet yield per pancreas weight (IEQ/g) and the rate of postpurification recovery in the top group were significantly higher than the COBE group (top: 8060 ± 1652 IEQ/g, bottom: 4572 ± 614 IE/g, COBE: 3900 ± 734 IE/g. p < 0.02 in top vs. COBE; top percentage of recovery: 99.3 ± 12.3%, bottom: 62.6 ± 8.8%, COBE: 49.5 ± 6.7%, p < 0.02 in top vs. bottom and COBE). The average sizes of purified islets in the top and bottom groups were significantly larger than COBE group (Average diameter top: 156 ± 8 μm, bottom: 147 ± 6 μm, COBE: 119 ± 6 μm, p < 0.01 in top vs. COBE and in bottom vs. COBE), which indicated that bottle method can reduce shear force during purification. Our new purification using top loading bottle method enabled us to obtain a high yield of porcine islets from marginal pancreata.  相似文献   
95.
For islet transplantation, maintaining organ viability after pancreas procurement is critically important for optimal graft function and survival. We recently reported that islet yield was significantly higher in the modified ET-Kyoto (MK) solution, which includes a trypsin inhibitor (ulinastatin), compared with the UW solution, and that the advantages of MK solution are trypsin inhibition and less collagenase inhibition. In this study, we compared ulinastatin with other trypsin inhibitors, gabexate mesilate, and nafamostat mesilate, in preservation solution for islet isolation. Ulinastatin was easily dissolved in ET-Kyoto solution, while ET-Kyoto with gabexate mesilate and nafamostat mesilate became cloudy immediately after addition. Although there were no significant differences in islet yield among the three groups, viability was significantly higher for the MK group than for the GK group or the NK group. The stimulation index was significantly higher for the MK group than for the GK group. In summary, there are no other trypsin inhibitors that are more effective than ulinastatin. Based on these data, we now use ET-Kyoto solution with ulinastatin for clinical islet transplantation.  相似文献   
96.
We report a case of a 29 year old male who at age 25, developed a pulmonary abscess in the left lower lobe. A left lower lobectomy was performed following two recurrences on antibiotic treatment. The result of histopathological examination confirmed congenital cystic adenomatoid malformation (CCAM), a congenital disease characterized by multiple cysts resulting from adenomatous hyperplasia of the bronchial epithelia. In many cases, respiratory distress occurs during the neonatal period, and in about 80–85% of patients, CCAM is diagnosed before the age of two years due to respiratory infection. CCAM which was diagnosed in adulthood is very rare.  相似文献   
97.
BACKGROUND: Parathyroid hormone-related protein (PTHrP) is produced by cancer cells and has been suggested to be responsible for malignancy-associated hypercalcemia and osteolysis after bone metatsases. Therefore, PTHrP is a promising target in the treatment of metastatic prostate cancer. METHODS: Seven PTHrP-derived peptides were prepared based on the HLA-A2 binding motif. These peptide candidates were screened by their ability to induce peptide-specific cytotoxic T lymphocytes (CTLs), and their ability to be recognized by immunoglobulin G (IgG). RESULTS: Both the PTHrP59-67 and PTHrP42-51 peptides were found to efficiently induce peptide-specific CTLs from peripheral blood mononuclear cells of HLA-A2+ prostate cancer patients with several HLA-A2 subtypes. These CTLs showed HLA-A2-restricted cytotoxicity toward prostate cancer cells. IgG reactive to the PTHrP42-51 peptide was frequently detected in prostate cancer patients. CONCLUSIONS: These results indicate that these two new PTHrP peptides will be useful in the peptide-based immunotherapy of HLA-A2+ prostate cancer patients, especially those with bone metastases.  相似文献   
98.
BACKGROUND: We hypothesized that impaired peripheral sensitivity to parathyroid hormone (PTH) may play a role in reelevation of PTH after successful operation for primary hyperparathyroidism (pHPT). METHODS: Factors affecting reelevation of PTH were determined in 90 patients who underwent parathyroidectomy for pHPT. PTH/nephrogenous cyclic adenosine monophosphate ratio, as an index of renal resistance to PTH, was examined in relation to factors shown to influence reelevation of PTH. RESULTS: Serum PTH levels were elevated above the upper limit of normal in 23 patients (26%) at 1 week and in 39 patients (43%) at 1 month after parathyroidectomy. These 39 normocalcemic patients with elevated serum PTH at 1 month after parathyroidectomy had a higher preoperative serum level of PTH and lower serum phosphate and 25-hydroxyvitamin D (25OHD) concentrations than those with normal PTH (n = 59). Elevated PTH and low 25OHD were shown by multivariate analysis to be significant predictors of reelevation of PTH. Renal resistance to PTH was higher in patients with vitamin D deficiency or renal insufficiency than in patients with normal serum vitamin D concentrations or normal renal function, and it increased according to increases in levels of PTH. CONCLUSIONS: The mechanism of PTH reelevation in patients with pHPT after successful parathyroidectomy appears to be renal resistance to PTH.  相似文献   
99.

Background

The purpose of this study was to assess changes in the three-dimensional (3D) load-bearing mechanical axis (LBMA) preoperatively and at 3 weeks and more than 1-year follow-up after total knee arthroplasty (TKA), and effects of the degree of constraint in the anteroposterior (AP) direction because of the retention of the posterior cruciate ligament (PCL) and the implant design on the changes in LBMA.

Methods

We evaluated 157 knees from 131 patients, including 79 knees that received meniscal-bearing-type (PCL-retaining) and 78 knees that received rotating-platform-type (PCL-substituting) prostheses. Quantitative 3D computed tomography was used to assess changes in the location of the pre- and postoperative LBMA at the tibial plateau level.

Results

Changes in the 3D axis were mainly found from medial to lateral and posterior to anterior in both implant designs with no significant differences. Change in the mediolateral (ML) direction was improved soon after TKA, but change in the AP direction improved more gradually over time. The different constraints in the AP direction because of the retention of the PCL and different implant designs did not affect the changes in the LBMA.

Conclusions

The LBMA in the AP direction more than 1 year postoperatively, as well as the LBMA in the ML direction at 3 weeks, appears to shift toward the location found in normal knees after TKA, regardless of the type of prosthetic constraint. These changes may be an important factor that influences the periarticular knee bone mineral density which load bearing may be related to.

Level of evidence

Level II, Prognostic study.
  相似文献   
100.
Background  The human homologue of Drosophila prune (PRUNE, which encodes h-prune) protein interacts with glycogen synthase kinase 3 and promotes cell motility. The aim of our study was to investigate the impact of immunohistochemically detected h-prune expression on the survival of patients with esophageal squamous cell carcinoma (ESCC). Methods  Immunohistochemical staining of h-prune was performed for 205 surgically resected specimens of ESCC. Results  In total, 43 (21%) of 205 ESCC cases were positive for h-prune. h-prune-positive ESCC cases showed a more-advanced T stage (P < 0.0001), N stage (P < 0.0001), and tumor stage (P < 0.0001) than h-prune-negative ESCC cases. In the group of 116 stage II and III ESCC cases, recurrence of ESCC was frequently found in h-prune-positive cases. In patients with lung recurrence, the tumors were more likely to be h-prune positive than h-prune negative. Univariate analysis revealed that T stage (P < 0.0001), N stage (P < 0.0001), tumor stage (P < 0.0001), and h-prune staining (P < 0.0001) were significant prognostic factors for survival. Multivariate analysis indicated that N stage (P = 0.0182) and h-prune staining (P < 0.0001) were independent predictors for survival. Conclusions  These results indicate that immunostaining of h-prune is useful to identify patients at high risk for recurrence or poor prognosis associated with ESCC.  相似文献   
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