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1.
Skin and soft tissue defects are sometimes problematic especially when the defects large, contaminated, irradiated, or poor blood supplied. The human mesenchymal stem cells (hMSCs) are proliferated upon basic fibroblast growth factor (bFGF) stimuli in vitro and in vivo. In this experiment, the skin and soft tissue defects are investigated if the wounds are able to be reepithelialized or accelerated by hMSCs, bFGF and porcine‐derived bilayered skin template.
1.5 × 1.5 cm2 nude rat skin and soft tissue defects including panniculus carnosus are excised and 1 × 106 hMSCs and various doses of bFGF (1–100 μg) applied. Before and after normal reepithelialization, the tissues are tested for protein expressions by immunohistochemistry and Western blotting.
The wound sizes are significantly decreased at day 7 with hMSCs with 1, 10, or 100 μg bFGF compared to hMSCs‐alone or medium‐only. All the wounds healed by day 42. 42 Kda and 38 Kda human‐derived pancytokeratin expressions, which do not cross‐react with murine antigens, by Western blotting significantly augmented by 10 μg bFGF compared to hMSCs‐alone. The epidermal immunolocalizations such as integrin α3 and SKALP (Skin‐derived Anti Leukoproteinase) are greatly elevated in time and dose‐dependent manner. Human pan‐cytokeratin expressions are immunoreactive even at day 42.
These data suggest the skin and soft tissue wound healing is accelerated by hMSCs together with bFGF, partly by means of differentiation of hMSCs toward epidermal components.  相似文献   
2.
DUSP6/MKP-3 is identified as a candidate tumor suppressor gene for pancreatic cancer. The aim of this study was to elucidate the roles of DUSP6 in the pancreatic carcinogenesis through the pancreatic intraepithelial neoplasia and/or intraductal papillary-mucinous neoplasms, both of which are considered to be precursor lesions of invasive carcinoma of the pancreas, by comparing with involvements of other major tumor suppressive pathways. Expressions of DUSP6, CDKN2A, TP53, and SMAD4 were investigated by immunohistochemistry in a total of 206 lesions of dysplastic ductal precursors and carcinomas retrieved from 52 pancreata with invasive ductal carcinomas and 51 of those with intraductal papillary-mucinous neoplasms. The intensity of staining was evaluated in lesions at different atypical grades and statistically compared among them. Mutations of KRAS2 were analyzed by methods of the allele-specific oligonucleotide hybridization and nucleotide sequencing. In pancreata with invasive ductal carcinomas, expressions of DUSP6 were abrogated exclusively in the invasive carcinoma cells in contrast to its fairly preserved expressions in pancreatic intraepithelial neoplasia. In pancreata with intraductal papillary-mucinous neoplasms, abrogated expressions of DUSP6 were observed in a relatively small fraction of intraductal adenoma/borderlines and intraductal carcinomas. Most of the intraductal adenoma/borderline lesions with abrogation of DUSP6 harbored mutations of KRAS2. None of the molecules was associated with each other in any grade of lesions. Morphological variations of papillae of the intraductal papillary-mucinous neoplasms were evaluated and analyzed for their associations with abrogations of the molecules, which resulted in finding of no significant associations. Our results suggest that the abrogation of DUSP6 is associated exclusively with progression from pancreatic intraepithelial neoplasia to the invasive ductal carcinoma while it is potentially associated with initiation of intraductal papillary-mucinous neoplasms with mutated KRAS2, which is independent of other major tumor suppressive pathways in both types of neoplasms.  相似文献   
3.
通过运用仿真人体模型对松果体区靶病灶直线加速器多聚弧照射的监测,论证直线加速器作为放射外科工具治疗颅内病变的科学性,探讨有关辐射参数对剂量分布的影响。作者认为,直线器放射外科可实现与伽玛马相似的剂量分布,同是神经外科安全有效的治疗技术,准直器孔径越小,照射范围越大,则剂量梯度即越大,剂量分布越理想;靶区最大剂量对上器孔径有相当高的依赖性,本文还就合理的照射弧范围及边缘处方剂量作了讨论。  相似文献   
4.
A 16-year-old patient with multiple sclerosis (MS) showed paroxysmal movement disorders during a recurrence of the disease. The paroxysms took the form ot brief unilateral dystonic posturings of the right body suggestive of paroxysmal dystonia (PD); they completely receded with acetazolamide. A single episode of a high amplitude, rythmic slow and coarse generalized tremor, present at rest and increasing with movement, particularly involving the head in a no-no movement, occurred soon after recovery from PD and lasted three hours. The present report provides evidence that MS has to be considered in the diagnostic approach to symptomatic childhood PD and underlines the efficacy of acetazolamide in the treatment of PD attacks. It also describes a rare paroxysmal movement disorder, defined as paroxysmal dystonic tremor, that can be considered as falling within the spectrum of PD.This study was partially supported by the Paolo Zorzi Association for Neurosciences, and the Harry De Jur Foundation.  相似文献   
5.
Since the first treatment of acoustic neurinoma using the γ-knife by Leksell, a series of cases have been reported with good control rates. However, the most frequent complication is delayed hearing loss which occurs in more than 50% of patients. The purpose of this study was to define a safe dose by analyzing the radiosurgical dose-response relationship and histological effects on the normal cochlear nerve in rabbit. The rabbits had computed tomography (CT)-guided stereotactic radiosurgery on their cochlear nerves in the internal auditory canal with a 4 mm collimator focusing of a γ-unit. Maximum doses of 10, 20, 30, 40, 60, 80, 100, 200 and 500 Gy were administered. After the radiosurgery, auditory brain stem responses (ABR) and the behavior of the rabbits were evaluated periodically. At the conclusion, histological investigations were performed. No physiological or histological findings were observed from doses of 30 Gy or below during the 12 month period after the radiosurgery. A dose of 100 Gy caused a severe ABR threshold elevation, vestibular dysfunction and facial palsy. Necrosis and demyelination of nerves were observed pathologically. In this study, we determined that the safe dose to the normal cochlear nerve during radiosurgery was under 40 Gy in rabbits, and complications seemed to vary due to individual differences in radiation tolerance.  相似文献   
6.
The aim of this study was to evaluate and compare the mitogenic effect of peritoneal fluid (PF) from women with mild and severe endometriosis on the endometrial stromal cell proliferation. Increasing concentrations of PF from women with and without mild or severe endometriosis were added to primary endometrial stromal cell cultures and3H-thymidine incorporation was used to assess DNA synthesis in these cultures. PF from women with mild endometriosis induced a statistically significant dose-dependent increase in stromal cell thymidine uptake ranged from 5.8 to 14.5 fold, whereas PF from women with severe endometriosis produced an average 51% inhibition of stromal cell proliferation of compared with cells exposed to non-endometriosis PF or exposed to nutrient medium supplemented with 2.5% calf serum alone. PF samples from patients with stage I endometriosis induced a statistically dose-dependent increase in stromal cell proliferation, whereas PF from patients with stage IV endometriosis caused a significant inhibition.  相似文献   
7.
目的:探讨进食评估问卷调查工具-10(eating assessment tool-10,EAT-10)中文版在急性期脑卒中后吞咽障碍评估中的信度和效度。方法:选择急性期脑卒中后住院患者180例,采用EAT-10中文版量表进行筛查评估,并用吞咽障碍的诊断金标准--视频透视吞咽功能检查(videofluoroscopic swallow study,VFSS)为效标进行检验。结果:180名入选患者中有130名问卷合格并顺利行VFS检查,EAT-10中文版总量表Cronbach’s α=0.845,各条目与总分均存在相关,相关系数最低的为条目2(r=0.271),相关系数最高的为条目3(r=0.772),重测信度均为0.7以上,重测信度符合要求。经调查员一致性信度检验,条目2有一位调查员的结果是恒定值,量表其余9个条目的一致相关系数均>0.7,各亚项和总分均值间一致性较高。分别对EAT-10分界值3,2,1进行效度检验,发现分界值1为最理想分界值,灵敏度及阴性预测值最高,判断吞咽障碍的灵敏度为77.9%,特异度为66.1%,阳性预测值71.6%,阴性预测值73.2%,阳性似然比2.30,阴性似然比0.33。结论:EAT-10中文版仅适用于已有饮水和进食经历的患者,EAT-10中文版对评估急性期脑卒中患者有良好的信度和效度,当分界值为1,EAT-10总分≥1时灵敏度和阴性预测值最佳,能够较好地预测急性期脑卒中患者吞咽障碍、吞咽能力受损、渗透和误吸。  相似文献   
8.
Hamasaki J  Tsuneyoshi I  Katai R  Hidaka T  Boyle WA  Kanmura Y 《Anesthesia and analgesia》2002,94(6):1434-40, table of contents
The actions of dexmedetomidine (DEX) on human vascular smooth muscle are unclear. We investigated its effects on isolated, endothelium-denuded human gastroepiploic arteries in vitro and compared them with clonidine (CLO). DEX had little direct effect on resting tension, whereas CLO produced small contractile responses, an effect which is blocked by the alpha(1)-adrenergic antagonist prazosin. DEX markedly enhanced the high K(+) (40 mmol/L)-induced contraction, and this effect was reversed by the alpha(2)-adrenergic antagonists yohimbine and rauwolscine but unaffected by prazosin. However, CLO had little effect on the K(+) contractions. Interestingly, larger concentrations (>10(-7) mol/L) of both alpha(2)-adrenergic stimulants significantly inhibited the contractions elicited by the alpha(1)-adrenergic agonist phenylephrine (10(-6) mol/L) and, to a lesser extent, those elicited by the alpha(1)/alpha(2)-agonist norepinephrine (10(-6) mol/L). These results suggest the possibility that DEX and CLO each have a high affinity for alpha(1)-adrenoceptors in human isolated gastroepiploic arteries, resulting in a reduced efficacy of alpha(1)-adrenergic activation by alpha-agonists. The differing affinities of the drugs for alpha(1)- and alpha(2)-adrenoceptors may help explain their additional actions: 1) DEX enhances the high K(+)-induced contraction presumably through alpha(2)-adrenoceptor activation, and 2) CLO acts on alpha(1)-adrenoceptors as a partial agonist when present alone. IMPLICATIONS: Dexmedetomidine may not directly affect smooth muscle in human peripheral resistance vessels within the usual range of plasma concentrations (<10(-7) mol/L) achieved in clinical practice. However, in large doses, it could enhance the response to nonadrenergic vasoconstrictor agonists while antagonizing the vasoconstrictor response to alpha(1)-adrenoceptor agonists.  相似文献   
9.
The Glasgow Prognostic Score (GPS), an inflammation-based score, has been used to predict the biologic behavior of malignant tumors. The aim of the current study was to elucidate a further significance of GPS in colorectal carcinoma. Correlation of GPS and modified GPS (mGPS), which are composed of combined score provided for serum elevation of C-reactive protein and hypoalbuminemia examined before surgical treatment, with clinicopathologic features was investigated in 272 patients with colorectal carcinoma. Survival of GPS 1 patients was significantly worse than that of GPS 0 patients (P= 0.009), and survival of GPS 2 patients was significantly worse than that of GPS 1 patients (P < 0.0001). Similarly, survival of mGPS 1 patients was significantly worse than that of mGPS 0 patients (P = 0.009), and survival of mGPS 2 patients was significantly worse than that of mGPS 1 patients (P = 0.0006). Multivariate analysis demonstrated that GPS (P < 0.0001) as well as tumor stage (P= 0.004) and venous invasion (P = 0.011) were factors independently associated with worse prognosis. Both GPS and mGPS could classify outcome of patients with a clear stratification, and could be applied as prognostic indicators in colorectal carcinoma.Key words: Colorectal carcinoma, Glasgow prognostic score (GPS), Prognostic indicatorAlthough many tumor-environmental elements, including both tumor-related and host-related factors, have been linked with tumor progression, host inflammatory response is one of the more important factors that has a role in the progression and/or development of tumors.1Serum elevation of C-reactive protein (CRP), an acute phase protein, has been shown to be a prognostic indicator in a variety of neoplasms, including colorectal carcinoma.25 Moreover, hypoalbuminemia brought about by malnutrition and related to cachexic condition has been reported to be correlated with an unfavorable prognosis of some gastrointestinal tumors.6,7The Glasgow prognostic score (GPS), which is a cumulative inflammation-based cancer-prognostic marker composed of serum elevation of CRP and decrease in albumin concentration, is likely to reflect host systemic inflammatory response and has been reported to be significant as a prognostic indicator in cancer-bearing patients.810Moreover, it has been found that hypoalbuminemia alone is unlikely to be associated with reduced survival likelihood in patients with colorectal carcinoma11; therefore, the GPS has been modified (mGPS), providing a score of 1 only for a case with serum elevation of CRP, and score of 0 for a case only with hypoalbuminemia or where neither was elevated. Although, until now, there have been some reports regarding the significance of GPS as a prognostic indicator in colorectal carcinoma,9,1116 the aim of this study was to elucidate further the significance of GPS and mGPS in colorectal carcinoma.  相似文献   
10.

Purpose

To evaluate the anatomical variations in the middle hepatic vein tributaries (V5/V8) for determining the reconstruction strategy in right lobe living donor liver transplantation (LDLT).

Methods

The V5/V8 variations were examined in 268 patients and were classified into three and two types, respectively. The reconstruction rate (RR), patency rate (PR) and clinical outcomes were retrospectively evaluated in 46 right lobe LDLT cases.

Results

In terms of V5 variations, the RR and PR were significantly higher for type 2 than type 3 (82.6 vs. 44.4 % and 73.7 vs. 25.0 %, respectively). The alanine aminotransferase level on postoperative day (POD) 5 in the V5 patent group was significantly lower than in the occluded group (123 vs. 191 IU/dL). Regarding V8 variations, the RR and PR were significantly higher for type 1 than type 2 (44.4 vs. 17.6 % and 75.0 vs. 33.3 %, respectively). The aspartate aminotransferase level on POD 3 was significantly lower in the V8 patent group than in the occluded group (50 vs. 121 IU/dL).

Conclusion

For right lobe grafts with single large V5 (type 2) or V8 (type 1) variations, reconstruction is necessary. Our new classification of the MHV tributaries is useful for determining the reconstruction strategy to use in right lobe LDLT.  相似文献   
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