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31.

Objectives

Sumac (Rhus coriaria L.) is widely used spice which has several properties such as antioxidant, anti-inflammatory and antimicrobial. The purpose of this animal study was to evaluate the effects of sumac extract on levels of receptor activator of nuclear factor-kappa B ligand (RANKL), osteoprotegerin (OPG) expression, serum oxidative status, and alveolar bone loss in experimental periodontitis.

Material and Methods

Twenty-four Wistar rats were separated into three groups: non-ligated (NL, n=8), ligature only (LO, n=8), and ligature and treated with sumac extract (S, n=8) (20 mg/kg per day for 11 days). A 4/0 silk suture was placed around the mandibular right first molars subgingivally; after 11 days, the rats were sacrificed, and alveolar bone loss was histometrically measured. The detection of RANKL and OPG were immunohistochemically performed. Levels of serum total antioxidant status (TAS)/total oxidant status (TOS), and oxidative stress index (OSI) were also analyzed.

Results

Alveolar bone loss was significantly greater in the LO group compared to the S and NL groups (p<0.05). The number of inflammatory cell infiltrate (ICI) and osteoclasts in the LO group was significantly higher than that of the NL and S groups (p<0.05). The number of osteoblasts in the LO and S groups was significantly higher than that of the NL group (p<0.05). There were significantly more RANKL-positive cells in the LO group than in the S and NL groups (p<0.05). OPG-positive cells were higher in S group than in LO and NL groups (p<0.05). TOS and OSI levels were significantly reduced in S group compared to LO group (P<0.05) and TAS levels were similar in S and NL group (p>0.05).

Conclusions

The present study showed that systemic administration of sumac extract may reduce alveolar bone loss by affecting RANKL/OPG balance, TOS and OSI levels in periodontal disease in rats.  相似文献   
32.
甲状腺术后瘢痕组织是甲状腺局部分切除术后由于手术方式及缝线填充而形成的组织,甲状腺术后瘢痕组织形成及其发生发展过程同一般的组织损伤修复病理过程一样,为渐进老化阶段的结缔组织,其内小血管稀少,胶原纤维增多[1]。由于甲状腺术后瘢痕组织其质地较硬,活动性差,超声声像图上表现缺乏典型特征,与癌灶极其相似,因此鉴别较困难。本文将介绍超声对于甲状腺术后的随诊应用,分析甲状腺术后瘢痕组织的超声检查特点并着重介绍超声动态观察甲状腺术后瘢痕组织的应用及其发展前景。  相似文献   
33.
34.
Otitis media (OM), a middle-ear infection, is the most common childhood illness treated by pediatricians. If inadequately treated, OM can result in long-term chronic problems persisting into adulthood. Children with chronic OM or recurrent OM often have conductive hearing loss and communication difficulties and require surgical treatment. Tympanostomy tube insertion, the placement of a small drainage tube in the tympanic membrane (TM), is the most common surgical procedure performed in children under general anesthesia. Recent clinical studies have shown evidence of a direct correspondence between chronic OM and the presence of a bacterial biofilm within the middle ear. Biofilms are typically very thin and cannot be recognized using a regular otoscope. Here we report the use of optical coherent ranging techniques to noninvasively assess the middle ear to detect and quantify biofilm microstructure. This study involves adults with chronic OM, which is generally accepted as a biofilm-related disease. Based on more than 18,537 optical ranging scans and 742 images from 13 clinically infected patients and 7 normal controls using clinical findings as the gold standard, all middle ears with chronic OM showed evidence of biofilms, and all normal ears did not. Information on the presence of a biofilm, along with its structure and response to antibiotic treatment, will not only provide a better fundamental understanding of biofilm formation, growth, and eradication in the middle ear, but also may provide much-needed quantifiable data to enable early detection and quantitative longitudinal treatment monitoring of middle-ear biofilms responsible for chronic OM.  相似文献   
35.
Aberrations in optical microscopy reduce image resolution and contrast, and can limit imaging depth when focusing into biological samples. Static correction of aberrations may be achieved through appropriate lens design, but this approach does not offer the flexibility of simultaneously correcting aberrations for all imaging depths, nor the adaptability to correct for sample-specific aberrations for high-quality tomographic optical imaging. Incorporation of adaptive optics (AO) methods have demonstrated considerable improvement in optical image contrast and resolution in noninterferometric microscopy techniques, as well as in optical coherence tomography. Here we present a method to correct aberrations in a tomogram rather than the beam of a broadband optical interferometry system. Based on Fourier optics principles, we correct aberrations of a virtual pupil using Zernike polynomials. When used in conjunction with the computed imaging method interferometric synthetic aperture microscopy, this computational AO enables object reconstruction (within the single scattering limit) with ideal focal-plane resolution at all depths. Tomographic reconstructions of tissue phantoms containing subresolution titanium-dioxide particles and of ex vivo rat lung tissue demonstrate aberration correction in datasets acquired with a highly astigmatic illumination beam. These results also demonstrate that imaging with an aberrated astigmatic beam provides the advantage of a more uniform depth-dependent signal compared to imaging with a standard gaussian beam. With further work, computational AO could enable the replacement of complicated and expensive optical hardware components with algorithms implemented on a standard desktop computer, making high-resolution 3D interferometric tomography accessible to a wider group of users and nonspecialists.  相似文献   
36.
PurposeComparative efficacy of exenatide versus insulin glargine primarily on glucemic control, and secondarily on body mass index (BMI), lipid profile and blood pressure, in type 2 diabetes mellitus (T2DM) patients suboptimally treated with metformin monotherapy.Material/MethodsForty-seven inadequately treated T2DM patients on metformin assigned to exenatide (n=18) or insulin glargine (n=29) for 26 weeks. Glycosylated hemoglobin (HbA1c), serum lipids, BMI, systolic and diastolic blood pressure, and adverse events, including episodes of hypoglycemia and gastrointestinal symptoms, were recorded.ResultsEither treatment had a similar favorable mean reduction in HbA1c. However, more patients in exenatide group achieved HbA1c ≤ 7% at the 26th week compared with insulin glargine group (p=0.036). Insulin glargine group had significantly more episodes of hypoglycemia compared with exenatide group (p=0.039). Gastrointestinal adverse events were non-significantly higher in the exenatide group. A significantly greater BMI reduction was observed in exenatide group, whereas BMI was not altered in insulin glargine group. Total and LDL cholesterol (p=0.012), and triglycerides (p=0.016) significantly decreased, whereas HDL cholesterol increased (p=0.021) in the exenatide group, whereas only total cholesterol decreased in insulin glargine group. Changes in systolic and diastolic blood pressure were insignificant in both groups.ConclusionsExenatide provided similar reduction in HbA1c, but fewer episodes of hypoglycemia, compared with insulin glargine. Exenatide had also a favorable effect on weight loss, although more gastrointestinal adverse events. Exenatide may provide a justified alternative in second line treatment of T2DM, but more trials are required to elucidate its long-term safety and cost-effectiveness.  相似文献   
37.
38.
目的 观察Ⅱ型胶原在T-2毒素诱导大鼠关节软骨早期损伤中的干预作用,在分子水平上寻找软骨损伤及修复的分子学生物标志,为探讨关节软骨损伤疾病的防治措施提供理论依据.方法 Wistar大鼠80只,按体质量随机分为4组:阴性对照组、阳性对照组、高剂量干预组、低剂量干预组,每组20只.阴性对照组食用常规成品颗粒饲料,其他3组食用含100 ng/kg T-2毒素染毒饲料;阴性对照组和阳性对照组饮自来水;低、高剂量干预组饮用含Ⅱ型胶原0.5、5.0 g/L的自来水.在3、5个月时处死大鼠,光镜下观察大鼠透明软骨的组织病理学改变,用酶联免疫吸附试验(ELISA法)检测大鼠血清Ⅱ型胶原羧基末端肽(CTX-Ⅱ)、软骨寡聚基质蛋白(COMP)及尿中吡啶啉(DPD)含量.结果 光镜下阳性对照组大鼠关节软骨细胞排列紊乱,软骨细胞变形、变性,可见大面积的软骨细胞坏死,而高、低剂量干预组表现为软骨表面原纤维形成,表层软骨细胞肿胀变圆,扁平的软骨细胞减少,软骨细胞簇集等骨关节炎早期病理改变.在3、5个月时,阴性对照组、阳性对照组、高剂量干预组、低剂量干预组大鼠血清CTX-Ⅱ含量分别为(18.77±4.61)、(25.07±9.17),(24.43±5.23)、(39.17±10.49),(21.11±5.02),(33.20±9.74),(19.87±4.53)、(29.73±9.32)μg/L;血清COMP含量分别为(5.43±2.75)、(6.38±2.23),(21.37±4.72)、(24.52±4.26),(17.27±4.77)、(20.32±4.74),(20.13±5.07)、(19.44±4.92)μg/L.其中,3个月时,与阴性对照组比较,阳性对照组血清CTX-Ⅱ含量明显升高(P<0.05),而低、高剂量干预组未见明显改变(P均> 0.05);5个月时,与阴性对照组比较,其他3组血清CTX-Ⅱ含量明显升高(P均< 0.05),而高、低剂量干预组明显低于阳性对照组(P均<0.05).3个月时,与阴性对照组比较,其他3组血清COMP含量明显升高(P均<0.05),而与阳性对照组比较,高剂量干预组血清COMP含量明显降低(P<0.05);5个月时,与阴性对照组比较,其他3组血清COMP含量明显升高(P均<0.05),而与阳性对照组比较,高、低剂量干预组血清COMP含量明显降低(P均<0.05).3、5个月时,上述4组大鼠尿液DPD含量分别为( 3.47±2.20)、(4.14±1.06),(4.09±2.48)、(4.33±3.43),(3.86±2.31)、(5.72±3.89),(3.58±2.77)、(4.23±2.90)μg/L,组间比较,差异无统计学意义(F值分别为2.608、2.436,P均>0.05).结论 Ⅱ型胶原能拮抗T-2毒素的软骨损伤作用,延缓关节软骨的破坏进程,降低大鼠血清中CTX-Ⅱ及COMP水平.  相似文献   
39.
摘要:目的 探讨白花蛇舌草-半枝莲药对组分对结肠腺癌Lovo细胞增殖、侵袭、迁移和凋亡的影响及作用机制。方法 将白花蛇舌草、半枝莲按质量1∶1进行3次煎煮,获得水提物,后取适量浸膏用石油醚回流脱脂,再以乙酸乙酯进行多次萃取,获得白花蛇舌草-半枝莲药对组分,并计算得率。实验分为对照组(正常培养Lovo细胞)、白花蛇舌草-半枝莲药对组分低剂量组(10 mg/L)、中剂量组(30 mg/L)及高剂量组(50 mg/L)。通过噻唑蓝比色法(MTT)检测各组细胞培养24、48、72 h后的增殖抑制率。各组细胞培养48 h后,流式细胞仪检测细胞周期分布;Transwell实验检测细胞侵袭能力;划痕实验检测细胞迁移能力;TUNEL法检测细胞凋亡情况;Western blot法检测Grb2相关结合蛋白1(Gab1)、血管内皮生长因子受体2(VEGFR-2)、磷脂酰肌醇3-激酶(PI3K)、苏氨酸激酶(Akt)、基质金属蛋白酶-9(MMP-9)、B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)蛋白表达情况。结果 化学萃取后的白花蛇舌草-半枝莲药对中主要含有对羟基苯乙酮、野黄芩苷、木犀草素和芹菜素4种化合物,组分得率为0.61%。与对照组相比,低、中、高剂量组细胞增殖抑制率升高,G1期肿瘤细胞比例增加,细胞凋亡指数增高,侵袭细胞数和划痕闭合率明显减小(均P<0.05),细胞中Gab1、VEGFR-2、PI3K、Akt、MMP-9、Bcl-2蛋白表达降低,Bax表达升高(均P<0.05),且存在剂量依赖性。结论 白花蛇舌草-半枝莲药对组分可抑制结肠腺癌Lovo细胞的增殖,降低其迁移和侵袭能力,诱导细胞凋亡,其机制可能与抑制Gab1/VEGFR-2/PI3K/Akt信号通路活化有关。  相似文献   
40.
Pneumothoraces are a possible sequela of chest trauma with potential morbidity and mortality if not recognized and treated promptly. A portable supine chest radiograph is frequently the first radiologic study performed in the setting of trauma. While large pneumothoraces can be readily recognized on these radiographs, smaller pneumothoraces are missed in up to 15 % of trauma patients. There are many radiographic signs of occult pneumothoraces, and we are presenting a new radiographic sign of occult pneumothorax. The floating cardiac fat pad sign occurs when pleural air collects anteriorly and superiorly in the most non-dependent portion of the chest lifting the pericardial fat pad off the diaphragm. Lung markings are still seen surrounding the pericardial fat pad due to the inflated lower lobe of the lung resting dependently. Rapid and accurate identification of pneumothoraces is critical but often difficult on chest radiographs. Although there are many existing radiographic signs for identification of pneumothorax, prospective identification of small pneumothoraces is still relatively poor. Here, we describe an additional sign which aides in the detection of pneumothoraces, the floating cardiac fat pad. When present, this should prompt further evaluation with chest CT or upright chest radiograph.  相似文献   
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