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73.
Fibrous dysplasia (FD) is a developmental tumor like condition that is characterized by replacement of normal bone by an excessive proliferation of cellular fibrous connective tissue intermixed with irregular bony trabeculae. Central giant cell granuloma (CGCG) is described as a benign lesion affecting the mandible and maxilla that consists of a massive fibrohistiocytic proliferation with numerous heavily hemosiderin-laden multinucleate-giant cells. A 20 year old woman present at the Department of Oral Medicine, Dentistry School, Tehran University of Medical Sciences with a slowly growing non painful swelling of the right mandible for one year. Our differential diagnosis was osteoma, osteoid osteoma and Fd. The histological feature reveal Central giant cell granuloma fibrous dysplasia. Central giant cell granuloma and fibrous dysplasia occurring in the same jaw is rarely reported in the literatures.  相似文献   
74.
Context: It is now clear that oxidative stress (OS) and chronic low-grade inflammation are two main pathways involved in polycystic ovary syndrome (PCOS) pathogenesis. Therefore, simultaneous targeting of these pathways by means of carvedilol and Semelil (ANGIPARS?), as established medicines with dual anti-cytokine and anti-oxidant potential may be a therapeutic alternative approach to the current treatments.

Objective: The objective of this study is to study the protective effects of carvedilol and ANGIPARS? on inflammatory and oxidative response in hyperandrogenism-induced polycystic ovary (PCO).

Materials and methods: The murine model of PCO was induced by letrozole (1?mg/kg/d; orally) and effective doses of carvedilol (10?mg/kg/d; orally) and ANGIPARS? (2.1?mg/kg/d; orally) were administrated for 21?d in PCO and non-PCO healthy rats. Ovarian folliculogenesis, sex hormones concentrations, OS, inflammatory, and metabolic biomarkers were assessed in serum and ovaries.

Results: PCO rats exhibited ovarian cystogenesis which was preserved by the application of carvedilol and ANGIPARS?. In comparison with controls, decreased level of the total antioxidant power (TAP) and higher levels of reactive oxygen species (ROS) and lipid peroxidation (LPO) in serum and ovaries (2.41?±?0.67 versus 0.72?±?0.11; and 0.17?±?0.04 versus 0.05?±?0.01; 5.48?±?1.30 versus 10.56?±?0.77; and 7.06?±?1.94 versus 17.98?±?0.98; p?<?0.05, respectively) were detected in PCO rats. Moreover, the PCO rats exhibited hyperandrogenism due to a 3.7-fold increase in serum testosterone concentration (35.04?±?3.17 versus 131.09?±?13.24; p?<?0.05) along with a 2.98-fold decrease in serum progesterone (6.19?±?0.40 versus 18.50?±?1.03; p?<?0.05) and 5.2-fold decrease in serum estradiol (9.30?±?0.61 versus 48.3?±?2.10; p?<?0.05) when compared with those of the control group. However, similar to the control group, normal levels of OS markers and sex hormones were detected in ANGIPARS? and carvedilol co-treated PCO rats. Besides, when compared with controls, increased levels of TNF-α (770.75?±?42.06 versus 477.14?±?28.77; p?<?0.05) and insulin (1.27?±?0.10 versus 0.36?±?0.05; p?<?0.05) in PCO rats were significantly inhibited by carvedilol and ANGIPARS? co-treatment.

Discussion and conclusion: We evidenced the beneficial effects of carvedilol and ANGIPARS? in PCO, which underpin the new alternative approach in using these kinds of medicines in female reproductive disorders.  相似文献   
75.
Human gammadelta T cells expressing a V gamma 9V delta 2 T-cell receptor (TCR) kill various tumour cells including autologous tumours. In addition to TCR-dependent recognition, activation of NKG2D-positive gammadelta T cells by tumour cell-expressed NKG2D ligands can also trigger cytotoxic effector function. In this study, we investigated the involvement of TCR versus NKG2D in tumour cell recognition as a prerequisite to identify tumour types suitable for gammadelta T-cell-based immunotherapy. We have characterized epithelial tumour cells of different origin with respect to cell surface expression of the known NKG2D ligands MHC class I-chain-related antigens (MIC) A/B and UL16-binding proteins (ULBP), and susceptibility to gammadelta T-cell killing. Most tumour cells expressed comparable levels of MICA and MICB as well as ULBP with the exception of ULBP-1 which was absent or only weakly expressed. Most epithelial tumours were susceptible to allogeneic gammadelta T-cell lysis and in the case of an established ovarian carcinoma to autologous gammadelta T-cell killing. Lysis of resistant cells was enhanced by pre-treatment of tumour cells with aminobisphosphonates or pre-activation of gammadelta T cells with phosphoantigens. A potential involvement of TCR and/or NKG2D was investigated by antibody blockade. These experiments revealed three patterns of inhibition, i.e. preferential inhibition by anti-TCR antibody, preferential inhibition by anti-NKG2D antibody, or additive blockade by anti-TCR plus anti-NKG2D antibodies. Our results indicate for the first time that the NKG2D pathway is involved in the lysis of different melanomas, pancreatic adenocarcinomas, squamous cell carcinomas of the head and neck, and lung carcinoma.  相似文献   
76.

Background

Keloids and hypertrophic scars are due to overgrowth of dermal collagen following trauma to the skin that usually cause major physical, psychological and cosmetic problems.

Methods

In this randomized controlled trial, with a paired design, 50 patients with 2 or more keloids were included. In the control group (50 lesions), intralesional triamcinolone acetonide (40 mg/mL) was injected at three-week intervals for a total of 18 weeks. In the other group (50 lesions), lesions were treated by verapamil (2.5 mg/mL) with the same therapeutic sessions. Scar evaluation at each stage and at the end of 3 months follow up was done by serial photographic records as well as by Vancouver Scar Scale (VSS).

Results

Mean zero VSS scores were achieved with only triamcinolone in respect of scar height (week 15th) and pliability (week 15th). No therapeutic event (parameter = 0) or significant improvement was seen in verapamil group.

Conclusion

Our results did not support verapamil’s capability in treatment of keloid nor hypertrophic scars.  相似文献   
77.
It is more than a decade that amniotic membrane has been used as a wound dressing because of its anti‐inflammatory, anti‐microbial, anti‐fibrotic, anti‐scarring properties, as well as its pain relieving and epithelialization promoting features. However, amniotic membrane had limited applications because it needs to suture in surgery, is highly fragile, firmly adhere to the wound and may cause bleeding and pain when changing the bandage. This study investigated the possibility of development of a novel amniotic‐based chitosan gel dressing as a potential wound repair substrate with marked efficacy. In this experiment, amniotic gel prepared based on chitosan/PVP gel containing human amniotic membrane extract (AME‐Gel) was investigated in terms of wound‐healing efficacy and scar preventive effects in a rat burn model. The levels of re‐epithelialization and dermal regeneration were examined by histological assessment using H&E and Masson's trichrome staining. Also, we clarified the mechanism of healing and cytokine‐releasing activities of AME as well as its effect on epithelization, angiogenesis, and fibroblast growth and migration. Our results revealed that AME‐Gel induces epidermal and dermal regeneration at a shorter time through formation of granulation tissue, enhancement of fibroblast proliferation, and improvement of blood capillary formation concomitant with developing collagen bundles. Therefore, AME‐Gel could be considered a simple and easy to be used as a biological dressing for any type of superficial burn wounds, without any adverse effects.  相似文献   
78.
Despite the need for alternative sources of human hematopoietic stem cells (HSCs), the functional capacity of hematopoietic cells generated from human embryonic stem cells (hESCs) has yet to be evaluated and compared with adult sources. Here, we report that somatic and hESC-derived hematopoietic cells have similar phenotype and in vitro clonogenic progenitor activity. However, in contrast with somatic cells, hESC-derived hematopoietic cells failed to reconstitute intravenously transplanted recipient mice because of cellular aggregation causing fatal emboli formation. Direct femoral injection allowed recipient survival and resulted in multilineage hematopoietic repopulation, providing direct evidence of HSC function. However, hESC-derived HSCs had limited proliferative and migratory capacity compared with somatic HSCs that correlated with a distinct gene expression pattern of hESC-derived hematopoietic cells that included homeobox (HOX) A and B gene clusters. Ectopic expression of HOXB4 had no effect on repopulating capacity of hESC-derived cells. We suggest that limitations in the ability of hESC-derived HSCs to activate a molecular program similar to somatic HSCs may contribute to their atypical in vivo behavior. Our study demonstrates that HSCs can be derived from hESCs and provides an in vivo system and molecular foundation to evaluate strategies for the generation of clinically transplantable HSC from hESC lines.  相似文献   
79.

Introduction

Key performance indicators are essential navigation tools for hospitals. They provide managers with valid information enabling them to identify institutional strengths and weaknesses and improve managerial performance. In this study, the synthesis of evidence relating to hospital performance indicators was carried out by means of a field review and the indicators were analyzed through the Best Fit Method.

Methods

The five-step approach of Arksey and O’Malley was used as follows: selection of the research question; search for related studies; selection and refinement of the studies; synthesis and tabulation of key information; derivation of the related summary and report. Applying the Best Fit Framework Synthesis Method, the initial themes and subthemes were created and a model of public hospitals performance evaluation finally generated.

Results

Forty-nine studies were considered eligible to form part of the synthesis. The final model included the efficiency/productivity, effectiveness and financial themes. The efficiency/productivity sub-themes incorporated human resources indicators, hospital beds, costs, operating room productivity, emergency rooms, ICU, radiology, labs, technology and equipment productivity. Other sub-themes relate to general indicators such as BOR, ALS, number of outpatients and hospitalized patients. Financial themes included profit, revenue, cash flow, cost, investment, assets, debt and liquidity. Concerning effectiveness, the indicators were categorized in terms of access (equity), safety, quality and responsiveness. The accountability indicators were classified into patient-centeredness, staff orientation, and social responsibility.

Conclusion

Hospital performance management is a multi-dimensional issue, each dimension having its own significance. Based on the evidence, indicators are dependent on the evaluation model employed, the evaluation objective, and the views of executive managers and participants in the study. Selection of the most appropriate indicators is therefore key to a comprehensive performance evaluation system.
  相似文献   
80.
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