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61.

Purpose

To examine the validity of our treatment strategy for spinal dural arteriovenous fistulae (SDAVF), based on the treatment results and the long-term outcome.

Methods

This study included 50 SDAVF patients (38 men, 12 women, mean age 63.2 years) with progressive myelopathy. The treatment strategy involved embolization as the initial management tool and surgery if embolization was considered unsuitable. Their medical records were evaluated to identify the treatment results and functional outcomes. The mean follow-up period was 81.2 months (range 27–184 months).

Results

Complete obliteration was achieved in 22 (71.0 %) of 31 embolized patients and in 18 of 19 (94.7 %) operated patients. The initial success rate was significantly lower in embolized than operated patients. At the last follow-up, 33 of the 50 patients (66 %) manifested improved gait and 16 (32 %) improved micturition. The activity of daily living (ADL) was improved in 33 (66 %). When we compared the rates of functional improvement at the last follow-up, there was no significant difference between patients treated initially by embolization or surgery.

Conclusions

The long-term outcomes in SDAVF patients treated by multidisciplinary management with first-line embolization were comparable to those in earlier surgical series. However, our results were unable to demonstrate the superiority of endovascular embolization to surgical treatment for SDAVF. For the purpose of justifying endovascular embolization as a first-line treatment for SDAVF, it will be necessary to show further improvement in both the initial treatment success and the complication rates.
  相似文献   
62.
Sir, We have read the paper of Buckingham et al. (2006) with considerableinterest because we have recently published a related study(Matsubayashi et al., 2006). Buckingham et al. (2006) reportedthat antiphospholipid antibodies (aPLs) do not appear selectivelyconcentrated in follicular fluids and, when present, do notadversely affect the reproductive outcome  相似文献   
63.
Malignant peripheral nerve sheath tumor (MPNST) is rare, highly aggressive, resistant to radiochemotherapy, and associated with poor prognosis. Basic research to develop new treatment regimes is critically needed. This study was designed to identify motogenic factor(s) involved in MPNST cell invasion and inhibitor(s) of such invasive activity. We profiled the invasion-inducing activities of eight motogenic growth factors on two human MPNST cell lines, FU-SFT8611 and 9817, using in vitro Matrigel invasion assays. Platelet-derived growth factor-BB (PDGF-BB) was identified as the most effective MPNST cell invasion-inducing factor. Epidermal growth factor (EGF) and hepatocyte growth factor (HGF) also stimulated invasion in one MPNST cell line. Expressions of PDGF-BB and EGF receptors (PDGFR-beta and EGFR) mRNAs were detected more frequently and their proteins were expressed at higher levels in MPNST tissues than benign peripheral nerve sheath tumors (schwannomas and neurofibromas). In both MPNST cell lines, PDGF-BB induced tyrosine phosphorylation of PDGFR-beta but not of PDGFR-alpha, and specific PDGFR-beta inhibition by small interfering RNA to the receptor inhibited PDGF-BB-stimulated MPNST cell invasion, suggesting the predominant role of PDGFR-beta. Inhibition of PDGFR-beta phosphorylation by pretreatment with herbimycin A and imatinib mesylate effectively suppressed basement membrane invasion and cell growth in vitro. No mutations were present in exons 12 and 18 of PDGFR-beta in both MPNST cell lines and 10 human MPNST tissues examined. Our results indicated that PDGF-BB enhanced the invasive activity of MPNST cells through PDGFR phosphorylation and that imatinib inhibited such activity. The results provide the ground for further assessment of the therapeutic potential of imatinib in suppressing the invasion and growth of MPNST.  相似文献   
64.

Background

Treatment of esophageal adenocarcinoma often involves surgical resection. Newer technologies in interventional endoscopy have led to a substantial paradigm shift in the management of early-stage neoplasia in Barrett’s esophagus comprising high-grade dysplasia (HGD), intramucosal carcinoma, and, in some cases, submucosal carcinoma. However, there has been no consensus regarding the indications for esophageal preservation in these cases. In this work, consensus guidelines were established for the management of early-stage esophageal neoplasia considering clinically relevant aspects (age, comorbidities, and social environment) in each scenario.

Methods

Seventeen experts were invited to participate based on their background and clinical expertise at high-volume centers. A questionnaire was created that included four clinical scenarios covering a wide range of situations within HGD and/or early esophageal neoplasia, particularly where controversies are likely to exist. Each of the clinical scenarios was open to discussion subdivided by patient age (20, 50, and 80 s). For each clinical scenario an expert was chosen to defend that position. Each defense triggered a subsequent discussion during a consensus meeting. Conclusions of that discussion together with an accompanying literature analysis allowed experts to confirm or change their original choices and served as the basis for the recommendations stated in this article.

Results

There was 100 % consensus supporting esophageal preservation in patients with HGD, independent of patient age or Barrett’s length. In patients with T1a adenocarcinoma, consensus for preservation was not reached (65 %) for young and middle-aged individuals but was supported for elderly patients (100 %). For T1b adenocarcinoma, consensus was reached for surgical resection (90 %), leaving organ preservation for patients with very low risk of nodal invasion or poor surgical candidates.

Conclusion

Advances in endoscopic imaging and therapy allow for organ preservation in most settings of early-stage neoplasia of the esophagus, provided that the patient understands the implications of this decision.  相似文献   
65.
We conducted a randomized, double-blind trial to assess the effect of 28.2 μg teriparatide versus placebo (1.4 μg teriparatide) on reduction of the incidence of vertebral fractures. Individuals enrolled in this study included patients with primary osteoporosis with one to five vertebral fractures and capable of self-supported walking. Attention was focused on incident vertebral fractures, change in bone mineral density (BMD) of the lumbar spine, and safety. A total of 316 subjects participated in the study, which lasted up to 131 weeks. Incident vertebral fractures occurred in 3.3 % of subjects in the 28.2 μg teriparatide-treated group and 12.6 % of subjects in the placebo group during the 78-weeks study period. Kaplan–Meier estimates of risk after 78 weeks were 7.5 and 22.2 % in the teriparatide and placebo groups, respectively, with a relative risk reduction of 66.4 % by teriparatide (P = 0.008). Lumbar BMD in the 28.2 μg teriparatide group increased significantly by 4.4 ± 4.7 % at 78 weeks, which was significantly higher than the corresponding data in the placebo group (P = 0.001). Adverse events were observed in 86.7 % of individuals in the teriparatide group and 86.1 % of those in the placebo group. In conclusion, weekly injection of a low-dose of teriparatide (28.2 μg) reduced the risk of incident vertebral fractures and increased lumbar BMD.  相似文献   
66.
This study reported the distribution of polycyclic aromatic hydrocarbons (PAHs) concentrations simultaneously obtained in gas/rain/particle in rain event from 2010 to 2012 in Osaka, Japan. A sampling method for rain and the materials of a rain collector were also surveyed. Benzene and a glass bottle were used to prevent the decrease of PAHs in rainwater. The average concentration of Σ9PAHs in rainwater ranged between 17.49 and 646.52 ng dm?3. The mean ratio of these Σ9PAHs in gas versus particles was 77.9 and 68.3 % during rain and no rain, respectively. During rain, the PAHs in particles were scavenged by rain and were incorporated via washout by collision with each other. Therefore, the ratio of PAHs in rainwater was similar to that in particles. The low molecular weight LMW-PAHs from gas were recognized as being dissolved in rain but did not affect the ratio of PAHs in rain. Four rings PAH were dominant in gas/rain/particles. The seasonal variation of Σ9PAHs in rainwater was reported and discussed, and the PAHs levels during the winter and spring were higher compared with that of summer and autumn. Furthermore, the sampling method of PAHs in snow is also developed.  相似文献   
67.
Klotho gene mutant mice (klotho mice, also called kl/kl) exhibit osteopetrosis in the metaphysis of femora and tibiae and die within 3 months. We previously showed by semiquantitative RT-PCR that osteoprotegerin (opg) expression levels in klotho mice were about 2-fold higher than those in wild-type mice in the bone marrow, spleen, and lung. To examine whether the high osteoprotegerin expression levels account for the osteopetrotic phenotype in the klotho homozygous mutant mice in vivo, we made double mutant mice by crossing klotho mutant and osteoprotegerin-deficient mice. Micro computed tomography analysis in the two-dimensional sagittal planes of the metaphyses and cross-sections of femoral midshaft revealed that the abnormally high fractional trabecular bone volume in klotho homozygous mice (kl/kl; 29.71%), which was about 4-fold higher compared with that of wild-type [klotho (+/+) opg (+/+)] mice (7.81%), was rescued by the coexistence of heterozygous mutation in opg gene locus (+/-; 8.36%). Single heterozygous mutation in the opg gene locus alone (without klotho mutation) did not show phenotype (trabecular bone volume, 5.84%; not significantly different from wild type). High levels of osteoprotegerin mRNA expression in the bone marrow in klotho mutant mice were reduced by the heterozygous mutation in the opg gene locus. Furthermore, high osteoprotegerin protein levels in klotho mutant mice were also reduced by the heterozygous mutations in opg gene locus. Thus, elevated levels of osteoprotegerin in mutant mice contribute at least in part to reveal the osteopetrotic phenotype in klotho mice.  相似文献   
68.
69.
An outbreak of an influenza like illness was found in a nursing home in Fukuoka in January, 1999. Results of hemagglutinin inhibition tests with paired sera of patients and rapid diagnosis kit for influenza A indicated that an influenza A (H3N2) outbreak had occurred. A total of 15 patients with influenza like illness from one residential area of the nursing home were administered amantadine, 100 mg per day for five days. Clinical records of 264 residents were surveyed retrospectively from the tenth to the thirty-first of January, 1999. Influenza like illness was found in 112 residents (42.4%). The incidence of influenza like illness differed by residential area, ranging from 27.6% to 54.0%. The mean duration of fever was 3.6 days among patients administered amantadine. The mean duration was 4.4 days for patients not administered amantadine. The incidence of influenza like illness decreased rapidly after amantadine administration in the residential area where amantadine administration was done. These results suggest that amantadine is effective in mitigating influenza symptoms in the elderly. Amantadine may be useful for diminishing the influence of influenza A outbreaks in nursing homes.  相似文献   
70.
BACKGROUND: The efficacy of long-term drug therapy for patients with hypertrophic obstructive cardiomyopathy (HOCM) remains unclear. This study was performed to characterize the echocardiographic findings of patients responsive to drug therapy. METHODS: Left ventricular outflow tract (LVOT) gradient and morphologic characteristics of the septum, posterior wall, and mitral valve were measured echocardiographically in 35 Japanese patients. The mean follow-up time was 41+/-22 months. RESULTS: Long-term drug therapy was effective in 14 patients and ineffective in 21 patients. Five of the refractory patients required mitral valve replacement to become free of symptoms. Only 5 of 21 patients whose LVOT gradient was 100 mm Hg were responsive to drug therapy, whereas 9 of 14 patients whose LVOT gradient was <100 mm Hg were responsive to drug therapy. Seven of eight patients with an asymmetric septal hypertrophy (ASH) ratio >==1.3 and LVOT gradient <100 mm Hg were responsive to drug therapy. Only 3 of 16 patients with an ASH ratio <1.3 were responsive to drug therapy. There was no correlation between the efficacy of drug therapy and the morphology of the mitral valve or the width of the LVOT. CONCLUSION: Our results demonstrate that drug therapy effectively reduces the LVOT gradient in patients with asymmetric septal hypertrophy and a less severe LVOT gradient.  相似文献   
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