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101.
The antigenicity of the influenza A virus hemagglutinin is responsible for vaccine efficacy in protecting pigs against swine influenza virus (SIV) infection. However, the antigenicity of SIV strains currently circulating in Japan and Vietnam has not been well characterized. We examined the antigenicity of classical H1 SIVs, pandemic A(H1N1)2009 (A(H1N1)pdm09) viruses, and seasonal human-lineage SIVs isolated in Japan and Vietnam. A hemagglutination inhibition (HI) assay was used to determine antigenic differences that differentiate the recent Japanese H1N2 and H3N2 SIVs from the H1N1 and H3N2 domestic vaccine strains. Minor antigenic variation between pig A(H1N1)pdm09 viruses was evident by HI assay using 13 mAbs raised against homologous virus. A Vietnamese H1N2 SIV, whose H1 gene originated from a human strain in the mid-2000s, reacted poorly with post-infection ferret serum against human vaccine strains from 2000-2010. These results provide useful information for selection of optimal strains for SIV vaccine production.  相似文献   
102.
Alpha satellite DNA is a major DNA component of primate centromeres. We previously reported that Azara's owl monkey has two types of alpha satellite DNA, OwlAlp1 and OwlAlp2. OwlAlp2 (344 bp) exhibits a sequence similarity throughout its entire length with alpha satellite DNA of closely related species. OwlAlp1 (185 bp) corresponds to the part of OwlAlp2. Based on the observation that the CENP-A protein binds to OwlAlp1, we proposed that OwlAlp1 is a relatively new repetitive DNA that replaced OwlAlp2 as the centromeric satellite DNA. However, a detailed picture of the evolutionary process of this centromere DNA replacement remains largely unknown. Here, we performed a phylogenetic analysis of OwlAlp1 and OwlAlp2 sequences, and also compared our results to alpha satellite DNA sequences of other primate species. We found that: (i) OwlAlp1 exhibits a higher similarity to OwlAlp2 than to alpha satellite DNA of other species, (ii) OwlAlp1 has a single origin, and (iii) sequence variation is lower in OwlAlp1 than in OwlAlp2. We conclude that OwlAlp1 underwent a recent and rapid expansion in the owl monkey lineage. This centromere DNA replacement could have been facilitated by the heterochromatin reorganization that is associated with the adaptation of owl monkeys to a nocturnal lifestyle.  相似文献   
103.
Trifurcated arch grafts (3-branch grafts) are now being used to repair the thoracic aorta in addition to conventional arch grafts (4-branch grafts). The anatomical shape of the 3-branch graft is different from the original vessel, so it is necessary for clinical application to evaluate blood flow distribution in the graft to assess whether there is adequate blood flow to the target organs. To achieve this, we developed a computational fluid dynamics (CFD) method to evaluate blood flow distribution in the grafts. Aortic blood flow was measured by phase-contrast magnetic resonance imaging (PC-MRI), and flow distribution into the branched vessels was obtained. The MRI image was used to create a patient-specific image model that represents the geometry of the aortic arch. The CFD analysis method was employed to determine a boundary condition of the blood flow analysis in the aorta using a patient-specific image model. We also created simplified models of 4-branch and 3-branch grafts and used our CFD analysis method to compare blood flow distribution among simplified models. It was found that blood flow distribution in the descending aorta was 71.3 % for the 4-branch graft and 67.7 % for the 3-branch graft, indicating that a sum of branching flow in the 3-branch graft was almost the same as the one in the 4-branch graft. Therefore, there is no major concern about implanting a new 3-branch graft. Our CFD analysis method may be applied to estimate blood flow distribution of a newly developed vascular graft prior to its clinical use and provide useful information for safe use of the graft.  相似文献   
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105.

Background

Transplantation of mesenchymal stem cells (MSCs) is one possible strategy to achieve articular cartilage repair. We previously reported that synovial MSCs were highly proliferative and able to undergo chondrogenesis. We also found that placing a suspension of synovial MSCs on a cartilage defect for 10 minutes promoted cartilage repair in rabbit and pig models. However, the in vivo efficacy of this approach has not been tested clinically.

Questions/purposes

We asked whether transplantation of synovial MSCs improves (1) MRI features, (2) histologic features, and (3) clinical evaluation scores in patients with cartilage defects in the knee?

Methods

Patients with a symptomatic single cartilage lesion of the femoral condyle were indicated for inclusion in our study, and between April 2008 and April 2011, 10 patients were enrolled in this study. All patients completed followups of 3 years or more. The average followup period was 52 months (range, 37–80 months). Synovial MSCs were expanded with 10% autologous human serum for 14 days after digestion. For transplantation, the patient was positioned so that the cartilage defect was facing upward, and synovial MSC suspension was placed on the cartilage defect with a syringe under arthroscopic control. The defect with the applied suspension then was held in the upward position for 10 minutes. Five patients underwent concomitant ACL reconstructions, among whom two had meniscus suturing performed simultaneously. For MRI quantification, the cartilage defect was scored from 0 to 5. Second-look arthroscopy was performed for four patients and biopsy specimens were evaluated histologically. Clinical outcome was assessed using the Lysholm score and Tegner Activity Level Scale at final followup. Comparisons of MRI and Lysholm scores before and after treatment for each patient were analyzed using the Wilcoxon signed-rank test.

Results

MRI score (median ± 95% CI) was 1.0 ± 0.3 before and 5.0 ± 0.7 after, and increased after treatment in each patient (p = 0.005). Second-look arthroscopy in four patients showed that the cartilage defect appeared to be qualitatively better in all cases. Histologic analyses showed hyaline cartilage in three patients and fibrous cartilage in one at the deep zone. The Lysholm score (median ± 95% CI) was 76 ± 7 before and 95 ± 3 after, and increased after treatment in each patient (p = 0.005). The Tegner Activity Level Scale did not decrease after treatment in each patient.

Conclusions

For this small initial case series, transplantation of synovial MSCs was effective in terms of MRI score, qualitative histology, and Lysholm score. The use of synovial MSCs has an advantage in that the cells can be prepared at passage 0 in only 14 days. Transplantation of synovial MSCs may be less invasive than mosaicplasty and autologous chondrocyte implantation. To conclusively show the effectiveness of this treatment requires comparative studies, especially with more established arthroscopic procedures, such as marrow stimulation techniques.

Level of Evidence

Level IV, therapeutic study.  相似文献   
106.
Frozen shoulder is a relatively common disorder that leads to severe pain and stiffness in the shoulder joint. Although this disorder is self‐limiting in nature, the symptoms often persist for years, resulting in severe disability. Recent studies using human specimens and animal models have shown distinct changes in the gene expression patterns in frozen shoulder tissue, indicating that novel therapeutic intervention could be achieved by controlling the genes that are potentially involved in the development of frozen shoulder. To achieve this goal, it is imperative to develop a reliable animal joint contracture model in which gene expression can be manipulated by gene targeting and transgenic technologies. Here, we describe a novel shoulder contracture mouse model. We found that this model mimics the clinical presentation of human frozen shoulder and recapitulates the changes in the gene expression pattern and the histology of frozen shoulder and joint contracture in humans and other larger animal models. The model is highly reproducible, without any major complications. Therefore, the present model may serve as a useful tool for investigating frozen shoulder etiology and for identifying its potential target genes. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:1732–1738, 2015.  相似文献   
107.
108.
109.
PURPOSE: To clarify the indications for autonomic nerve-sparing operations for rectal cancer, the presence of lymph nodes and metastasis in the tissue around the autonomic nerve were examined in 28 rectal cancer patients. These were staged as pT2 in 8 patients, pT3 in 19 patients, and pT4 in 1 patient histopathologically. METHODS: The specimens of the autonomic nerve including the inferior mesenteric plexus, preaortic plexus, superior hypogastric plexus, hypogastric nerve, and pelvic plexus were removed with radical abdominopelvic lymphadenectomy after the autonomic nerve-sparing rectal cancer operation. RESULTS: In the tissue around the autonomic nerve, lymph nodes were 11.2±9.6 in number and 2.6±2.4 mm in size (mean ± standard deviation). The frequency of presence of lymph nodes was higher and the number of lymph nodes was larger in the inferior mesenteric plexus (70.4 percent; 3.6) and the preaortic plexus (66.7 percent; 2.1) than in the left and right pelvic plexuses (39.1 percent, 1; 36 percent, 1). Metastasis to the lymph nodes or lymphatic permeation in the tissue around the autonomic nerve were observed in four cases (14.3 percent) of lower rectal cancer, consisting of three with Stage III cancer (pT3, pN1-3, and M0) and one with Stage IV cancer (pT4, pN1, and pM1 (HEP)). CONCLUSION: Radical rectal excision that includes lymph nodes and adjacent tissue around the autonomic nerves may result in metastatic tumor removal that would otherwise be left in situ with nerve-sparing techniques for advanced rectal cancer in Stage III.  相似文献   
110.
Summary The long-term effect of calcium channel blockers on chronic heart failure is disappointing, probably because of reflex sympathetic activation through arterial vasodilation. However, nilvadipine may be beneficial for treatment of chronic heart failure since this drug has minimal effects on sympathetic activation. In this study, the effects of 12-week administration of nilvadipine or placebo on symptoms of heart failure and cardiac function were investigated in 23 patients with mild-to-moderate chronic heart failure in a double-blind trial. The patients were randomly assigned to either a nilvadipine group (16 mg daily) or a placebo group. Intergroup comparisons did not show significant differences in any parameters. Serious adverse effects were not observed during the study. Thus, this study failed to show any beneficial effect of nilvadipine in the long-term treatment of patients with chronic heart failure. We conclude that the long-term administration of nilvadipine (16 mg daily) is neither effective nor harmful in the treatment of patients with chronic heart failure.Other members are listed in the appendix.  相似文献   
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