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There has been considerable research on the involvement of RhoA/Rho kinase signalling in smooth muscle contractions. However, only a few reports have addressed the specific role of Rac1, which is a member of the Rho GTPase superfamily. Therefore, this study investigated the role of Rac1‐related pathways in bronchial smooth muscle (BSM) contractions. Bronchial rings isolated from mice were suspended in an organ bath, and the isometric contractions of circular smooth muscles were monitored. The phosphorylation of myosin light chains (MLCs) was analysed by immunoblotting. The Rac1 inhibitor EHT1864 inhibited carbachol (CCh)‐induced BSM contractions, although high K+ depolarization‐induced BSM contractions were not significantly attenuated by EHT1864. Moreover, high K+‐ and phorbol 12,13‐dibutyrate (PDBu; PKC activator)‐induced contractions were not attenuated by Rac1 inhibition, whereas sodium fluoride (NaF)‐induced force development was inhibited by EHT1864. The gene and protein expression of Rac1 was increased in the BSM of a murine model with antigen‐induced airway hyper‐responsiveness (AHR). In addition, an increased force of the BSM contractions in AHR was suppressed by EHT1864 treatment, suggesting that the up‐regulation of Rac1 is involved in AHR. These findings suggest that an increase in Rac1‐mediated signalling is involved in the augmented contractions of BSMs in antigen‐induced AHR mice.  相似文献   
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PurposeThis study compared the clinical success rates of mandibular fracture treatment using reconstruction plates or miniplates and clarified the selection criteria for reconstruction plates.MethodsAll patients who had surgically-treated mandible fractures from 2008 to 2017 with sufficient follow-up were retrospectively analyzed for information about the fracture condition, treatment, and outcomes.ResultsA total of 126 surgically-treated mandible fractures without mandibular condylar fracture in 105 patients (76 male, 29 female) were included. Reconstruction plates were used in 32 fractures with very good postoperative occlusal function. Four cases with complications requiring reoperation were treated using only miniplates. Variables that were statistically associated with follow-up surgery included simple versus comminuted mandible fracture, and the absence of teeth that could be used for intermaxillary fixation (P < 0.05). In the miniplates treatment for comminuted fracture, there was a significant difference in the treatment outcome depending on the number of free bone-fragments and the presence of bone-fragments requiring removal within 1 cm (P < 0.05).ConclusionReconstruction plates provided better treatment outcomes for comminuted fractures and fractures without teeth. Selecting a reconstruction plate that is capable of sufficiently overloading is important in comminuted fractures with multiple free bone-fragments and bone-fragments requiring removal.  相似文献   
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Assessment of liver fibrosis in patients with chronic hepatitis C (CHC) is critical for predicting disease progression and determining future antiviral therapy. LecT-Hepa, a new glyco-marker derived from fibrosis-related glyco-alteration of serum alpha 1-acid glycoprotein, was used to differentiate cirrhosis from chronic hepatitis in a single-center study. Herein, we aimed to validate this new glyco-marker for estimating liver fibrosis in a multicenter study. Overall, 183 CHC patients were recruited from 5 liver centers. The parameters Aspergillus oryzae lectin (AOL) / Dature stramonium lectin (DSA) and Maackia amurensis lectin (MAL)/DSA were measured using a bedside clinical chemistry analyzer in order to calculate LecT-Hepa levels. The data were compared with those of seven other noninvasive biochemical markers and tests (hyaluronic acid, tissue inhibitor of metalloproteases-1, platelet count, aspartate aminotransferase-to-platelet ratio index [APRI], Forns index, Fib-4 index, and Zeng's score) for assessing liver fibrosis using the receiver-operating characteristic curve. LecT-Hepa correlated well with the fibrosis stage as determined by liver biopsy. The area under the curve (AUC), sensitivity, and specificity of LecT-Hepa were 0.802, 59.6%, and 89.9%, respectively, for significant fibrosis; 0.882, 83.3%, and 80.0%, respectively, for severe fibrosis; and 0.929, 84.6%, and 88.5%, respectively, for cirrhosis. AUC scores of LecT-Hepa at each fibrosis stage were greater than those of the seven aforementioned noninvasive tests and markers. Conclusion: The efficacy of LecT-Hepa, a glyco-marker developed using glycoproteomics, for estimating liver fibrosis was demonstrated in a multicenter study. LecT-Hepa given by a combination of the two glyco-parameters is a reliable method for determining the fibrosis stage and is a potential substitute for liver biopsy. (HEPATOLOGY 2012).  相似文献   
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We present a case of carcinoma ex pleomorphic adenoma on the right buccal mucosa in a 52-year-old Japanese woman. Based on the histopathology, the excised tumor was the non-invasive type, but the majority of the tumor consisted of poorly-differentiated adenocarcinoma cells. We performed proton radiation after the surgery. The patient was well, without evidence of disease, 48 months after surgery. Carcinoma ex pleomorphic adenoma in the buccal mucosa has been reported in only four cases during the past twenty years. Therefore, our case was comparatively rare.  相似文献   
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Purposes

Reconstruction of the right inferior hepatic vein (RIHV) presents a major technical challenge in living donor liver transplantation (LDLT) using right lobe grafts.

Methods

We studied 47 right lobe LDLT grafts with RIHV revascularization, comparing one-step reconstruction, performed post-May 2007 (n = 16), with direct anastomosis, performed pre-May 2007 (n = 31).

Results

In the one-step reconstruction technique, the internal jugular vein (n = 6), explanted portal vein (n = 5), inferior vena cava (n = 3), and shunt vessels (n = 2) were used as venous patch grafts for unifying the right hepatic vein, RIHVs, and middle hepatic vein tributaries. By 6 months after LDLT, there was no case of occlusion of the reconstructed RIHVs in the one-step reconstruction group, but a cumulative occlusion rate of 18.2 % in the direct anastomosis group. One-step reconstruction required a longer cold ischemic time (182 ± 40 vs. 115 ± 63, p < 0.001) and these patients had higher alanine transaminase values (142 ± 79 vs. 96 ± 46 IU/L, p = 0.024) on postoperative day POD 7. However, the 6-month short-term graft survival rates were 100 % with one-step reconstruction and 83.9 % with direct anastomosis, respectively.

Conclusion

One-step reconstruction of the RIHVs using auto-venous grafts is an easy and feasible technique promoting successful right lobe LDLT.  相似文献   
90.
Reconstruction of inferior vena cava (IVC) defects after surgical resection of the IVC is associated with significant complications, such as venous thrombosis and graft infection. We herein report a new technique called “tube cavoplasty” that uses only autologous venous grafts to reconstruct IVC defects after resection of leiomyosarcomas of the IVC. The patient’s own left internal jugular and left external iliac veins are procured independently and incised along their axes to create an independent venous patch that is approximated together to make a wider “tube” graft. The size and length of the “tube” graft perfectly matches the IVC defect. In this study, no complications associated with this new procedure were observed except for transient mild edema of the left leg. This new technique could be a valuable tool to reconstruct IVC defects, such as those that occur after resection of IVC tumors or IVC stenosis for Budd–Chiari syndrome.  相似文献   
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