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11.
Hemodynamic effects of 2 mg of sublingual molsidomine were evaluated in 11 patients with ischemic heart disease using a weight-sustaining isometric exercise (WSIE) that we developed. Left ventricular end diastolic pressure (LVEDP), mean pulmonary pressure, mean systemic arterial pressure (mAP), cardiac index and stroke work index increased significantly during WSIE before and after molsidomine. Although WSIE resulted in a similar rise of mAP before and after molsidomine, the increment value of LVEDP during WSIE was significantly lower after molsidomine. The recovery time to the resting state of all parameters was shorter and the left ventricular function curves showed a leftward deviation with molsidomine. In conclusion, the results suggest that molsidomine will produce a preload reduction and improve the left ventricular function during WSIE in patients with ischemic heart disease.  相似文献   
12.
Activated T lymphocytes constitute a major component of inflammatory cells in the early periodontal lesion, and also appear in the gingival crevicular fluid. In an attempt to clarify the relationship between the ICAM-1 (CD54) expression of pocket epithelium in gingiva and the infiltrating lymphocyte population, we carried out an analysis of CD11a+ (LFA-lα), CD25+ (IL-2Rα) and CD4+ (Th) cells subjacent to ICAM-1-expressing pocket epithelia and CD11a+ CD25+CD4+ cells in gingival crevicular fluid (GCF). GCF was collected by crevicular washing from 16 patients with periodontitis (P group) and 3 subjects with healthy gingiva (H group). Peripheral blood (PB) was collected at the same time. Mononuclear cells were isolated by Ficoll-paque gradient centrifugation from GCF and PB. Monoclonal antibodies (mAb) to CD11a, CD25, and CD4 were used for three-color flow cytometry. Gingival biopsies were obtained from 7 patients in P group and 3 subjects in H group. Serial cryostat sections (6 μm in thickness) were prepared from each biopsy, on which a double staining was performed. The number of CD11a+ CD25+ CD4+ cells and the fluorescence intensity of FITC conjugated anti-CD 11a were significantly higher in GCF than in PB (p≤0.001 to p≤0.01). CD11a+ CD25+CD4+ cells were not detected in GCF in H group. The pocket epithelia expressed CD54 in P group, but not in H group. The number of CD11a+, CD25+ and CD4+cells infiltrating the connective tissue subjacent to the upper, middle and lower parts of the CD54 positive pocket epithelium (n=16) was 141±26, 38±13, 144±29 (cells/0.04 mm2), respectively, whereas in the CD54 negative pocket epithelium, it was (n=5) 9±2, 3±1, 8±3. In P group, the CD11a+CD25+CD4+cell number in GCF correlated with CD25+, CD11a+cells in the connective tissue subjacent to the CD54+pocket epithelium. These results indicate that expression of ICAM-1 in pocket epithelium is relevant to the migration of CD11a, CD25, CD4 positive cells in connective tissue subjacent to the pocket epithelium into the periodontal pocket. Assessing the relationship of our findings and other adhesion molecules would offer important clues to the understanding of T cell migration in affected gingiva.  相似文献   
13.
This study evaluated the effect of chlorhexidine/thymol (CHX/T) and fluoride (F) varnishes on biofilm formation in vitro. Hydroxyapatite discs coated with varnish were first immersed in saline for 0, 3, 7 or 14 d, then immersed in pasteurized saliva. The discs were incubated for 20 h with a bacterial suspension containing Actinomyces naeslundii, Fusobacterium nucleatum, Streptococcus oralis, and Veillonella dispar. Uncoated discs were used as controls. Growth of bacteria on the discs was evaluated by culture and by scanning electron microscopy (SEM). Bacterial vitality was examined by fluorescence staining. In the CHX/T-treated group, bacterial accumulation was delayed, and the total number of bacteria was significantly lower than in the controls. In the F-treated group, the total number of bacteria did not differ from the control, although the number of S. oralis was lower. Bacterial vitality in the CHX/T and F groups did not differ from that in the controls. The total number of bacteria on the CHX/T-treated discs immersed in saline was significantly higher than that on the non-immersed discs. Biofilm development was inhibited by the CHX/T varnish but not by the F varnish. The effect of the CHX/T varnish decreased following the immersion of discs in saline.  相似文献   
14.
15.
A bi-layered silicon-releasable membrane consisting of a siloxane-poly(lactic acid) (PLA)-vaterite hybrid material (Si-PVH) microfiber mesh and a PLA microfiber mesh has been developed by an electrospinning method for guided bone regeneration (GBR) application. The bi-layered membrane was modified to a three-laminar structure by sandwiching an additional PLA microfiber mesh between the Si-PVH and PLA microfiber meshes (Si-PVH/PLA membrane). In this study, the influence of gamma irradiation, used for sterilization, on biological properties of the Si-PVH/PLA membrane was evaluated with osteoblasts and fibroblasts. After gamma irradiation, while the average molecular weight of the Si-PVH/PLA membrane decreased, the Si-PVH/PLA membrane promoted cell proliferation and differentiation (alkaline phosphatase activity and calcification) of osteoblasts, compared with the poly(lactide-co-glycolide) membrane. These results suggest that the gamma-irradiated Si-PVH/PLA membrane is biocompatible with both fibroblasts and osteoblasts, and may have an application for GBR.  相似文献   
16.

Purpose

An incisional surgical site infection (I-SSI) is a frequently observed complication following colorectal surgery. Intraoperative wound management is one of the most important factors that determine the incidence of postoperative I-SSI. The purpose of this study was to assess the impact of the methods used for intraoperative wound management on the incidence of I-SSI following elective surgery for colorectal cancer.

Methods

Between November 2009 and February 2011, the data of 1,980 consecutive patients who underwent elective colorectal resection for colorectal cancer were prospectively collected from 19 affiliated hospitals. The incidence of and risk factors for I-SSI were investigated.

Results

Overall, 233 I-SSIs were identified (11.7 %). Forty-two possible risk factors were analyzed. Using a multivariate analysis, the independent risk factors for I-SSI were identified to be a high body mass index, previous laparotomy, chronic liver disease, wound length, contaminated wound class, creation or closure of an ostomy, right hemicolectomy procedure, the suture material used for fascial closure and the incidence of organ/space SSI.

Conclusion

To prevent I-SSI following elective colorectal surgery, it is crucial to avoid making large incisions and reduce fecal contamination whenever possible. A high quality randomized control trial is necessary to confirm the definitive intraoperative procedure(s) that can minimize the incidence of I-SSI.  相似文献   
17.
Taste receptor cells fire action potentials in response to taste substances to trigger non‐exocytotic neurotransmitter release in type II cells and exocytotic release in type III cells. We investigated possible differences between these action potentials fired by mouse taste receptor cells using in situ whole‐cell recordings, and subsequently we identified their cell types immunologically with cell‐type markers, an IP3 receptor (IP3R3) for type II cells and a SNARE protein (SNAP‐25) for type III cells. Cells not immunoreactive to these antibodies were examined as non‐IRCs. Here, we show that type II cells and type III cells fire action potentials using different ionic mechanisms, and that non‐IRCs also fire action potentials with either of the ionic mechanisms. The width of action potentials was significantly narrower and their afterhyperpolarization was deeper in type III cells than in type II cells. Na+ current density was similar in type II cells and type III cells, but it was significantly smaller in non‐IRCs than in the others. Although outwardly rectifying current density was similar between type II cells and type III cells, tetraethylammonium (TEA) preferentially suppressed the density in type III cells and the majority of non‐IRCs. Our mathematical model revealed that the shape of action potentials depended on the ratio of TEA‐sensitive current density and TEA‐insensitive current one. The action potentials of type II cells and type III cells under physiological conditions are discussed.  相似文献   
18.
Background contextThe clinical morphology of a filum terminale arteriovenous fistula (f-AVF) is well known; however, pathological details of the fistulized portion are unknown. Herein, we report the pathological findings of the f-AVF.Study designCase report and literature review.PurposeTo present a detailed pathological examination of the fistulized portion of the f-AVF.MethodsA 71-year-old man presented with gradually worsening bilateral foot paresthesias and anal dysesthesia. T2-weighted magnetic resonance imaging showed flow voids surrounding an edematous conus medullaris and cauda equina with spinal stenosis at L3–L4 and L4–L5. Spinal digital subtraction angiography demonstrated an f-AVF fed by the left T9 intercostal artery.ResultsWe performed laminotomies of L3 and L4 to open the dura mater and found a hypertrophic filum terminale. It was resected, leaving a length of 2 cm between the abnormal proximal end and normal distal end. The f-AVF completely disappeared after the surgery. On pathological examination, the filum terminale included two vessels at the proximal end and one at the distal end. At the proximal end, immunostaining showed one vessel that was definitively an artery with both an internal elastic membrane (IEM) and smooth muscle. The other was a vein and lacked an IEM. On the distal side, the collagen fibers gradually increased, the IEM partially disappeared from the arterial wall, and the vein became arterialized with a thin IEM. At the distal end the two vessels joined. Therefore, we speculated that the fistulized portion of the f-AVF was not a fistula point but had some lengths where the artery had characteristics of a vein and there was venous arterialization.ConclusionsThe filum arteriovenous shunting occurred at the portion where there was venous arterialization and the artery had the characteristics of a vein. Therefore, resecting the filum terminale requires more proximal from the normal distal end.  相似文献   
19.
20.
A less invasive transsphenoidal approach with a keyhole dural opening for intrasellar arachnoid cysts is described. This approach was used to address seven sellar cystic lesions with suprasellar extension; they were six intrasellar arachnoid cysts (IACs) and one Rathke’s cleft cyst (RCC). In all cases, preoperative MRI revealed cerebrospinal fluid (CSF) intensity on both T1- and T2-weighted images. On preoperative contrast-enhanced MRI, five of the six IACs manifested posterior displacement of the flattened pituitary gland toward the dorsum sellae; one of the six IACs and the RCC exhibited a flattened pituitary gland on the anterior surface of the cyst. Wide cyst cisternostomy through a keyhole dural opening was carried out safely using a microscope with the support of a thin angled endoscope (30° and/or 70°, diameter 2.7 mm). As we aimed to avoid iatrogenic injury of the pituitary function, we found it difficult to obtain a sufficiently wide and precise opening of the cyst wall when the pituitary gland was located on the anterior surface of the cyst wall. Our approach facilitates safe cyst cisternostomy as wide as that obtainable by transcranial manipulation. In addition, CSF leakage is prevented by dural plasty using the fascia lata and stitching with 6-0 monofilament sutures. This technique can be adapted to address various sellar cystic lesions. However, as the posterior or anterior displacement of the normal pituitary gland in the presence of IACs or RCCs, respectively, affects the width of the cyst opening, our technique is more suitable for IACs than RCCs.  相似文献   
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