纳米淡水珍珠粉对成骨相关基因表达的影响

背景:珍珠中高含量的钙离子可以促进钙盐沉积,抑制破骨细胞的骨吸收活性,促进骨再生,且其含有的水溶性蛋白具有骨诱导作用,可促进成骨细胞的分化。目的:观察纳米淡水珍珠粉对成骨细胞成骨相关基因表达的影响。方法:取第3代小鼠成骨细胞MC3T3-E1细胞,分别与纳米淡水珍珠粉(实验组)、纳米羟基磷灰石(对照组)共培养,以单独培养的细胞为阴性对照。培养7 d后,采用RT-PCR实验检测各组Runx2、骨桥蛋白、Ⅰ型胶原m RNA的表达。结果与结论:(1)实验组、对照组Runx2与骨桥蛋白mRNA表达量高于阴性对照组(P <0.05),并且实验组Runx2与骨桥蛋白m RNA表达量高于对照组(P <0.05);(2)实验组Ⅰ型胶原m RNA表达量高于对照组、阴性对照组(P <0.05),对照组与阴性对照组Ⅰ型胶原m RNA表达量比较差异无显著性意义(P> 0.05);(3)结果表明,纳米淡水珍珠粉较纳米羟基磷灰石更能显著促进成骨相关基因Runx2、骨桥蛋白、Ⅰ型胶原m RNA的表达。     

不同粒径银粒子的体外细胞毒性比较

目的 比较纳米银粉末与微米银粉末体外细胞毒性的差异,并初步探讨毒性机制与粒径大小的相关性.方法 四种不同粒径银粒子通过扫描电镜确定其粒径分布后,制备成不同浓度的含银培养液与L929细胞接触培养,通过倒置相差显微镜观察其形态,采取MTT（四唑盐）比色法量化细胞毒性,计算相对增值率（RGR）,并进行毒性评价.结果 当银浓度在一定范围内（2.5～25）μg//mL,纳米银粒子呈现轻微细胞毒性（0～1）级,RGR与含银量呈量-效关系;随着浓度增高到大于50μg/mL时,与之共培养的细胞,形态上发生较大改变,显示明显的细胞毒性,量-效相关性也随之消失.粒径较小的微米银在银浓度达到250μg/mL时显示明显的细胞毒性.而粒径较大的两组微米银粒子在所有试验浓度下,共培养的细胞生长良好,未见明显的细胞毒性.结论 粒径不同的银粒子的体外细胞毒性有较大差异.同等剂量下,纳米级的银粒子和粒径较小的微米级银粒子,比粒径较大的微米级银粒子的体外细胞毒性更大.     

气相法纳米二氧化硅季胺盐衍生物的合成和性能

考察实验室制备的一种气相法纳米二氧化硅季胺盐衍生物的合成及抗菌性能。通过红外光谱、激光粒度Zeta电位仪对气相法纳米二氧化硅季铵盐衍生物进行表征和测定．用悬菌定量实验（Suspension quantitative test）研究其抗菌性能，结果显示：（1）气相法纳米二氧化硅的零点位在pH=4．8，气相法纳米二氧化硅季铵盐衍生物的零电位在pH=10．5～10．8之间．季铵盐的引入使其零电位发生了较大的位移；（2）悬菌定量实验对大肠杆菌（8099）。金黄色葡萄球菌（ATCC6538）以及白色念珠菌（ACTT10231）的15min抑菌率分别为99．99％，99．99％和94．12％，显示气相法纳米二氧化硅季胺盐衍生物对细菌有较强的抑菌效果。     

肝脏组织工程纳米纤维支架材料的比较研究

探讨海藻酸钠、壳聚糖和PLGA纳米纤维支架的机械稳定性、生物相容性及细胞在其表面的生长规律,寻找合适的肝脏组织工程支架材料。用静电纺丝的方法分别制备海藻酸钠、壳聚糖和PLGA纳米纤维支架,观察材料的机械稳定性及肝细胞在材料表面的活性和生长情况。接种后0.5 h内,肝细胞在壳聚糖和海藻酸钠材料表面贴壁,生长良好。第二天起,肝细胞在壳聚糖表面逐渐聚集生长,形成聚集体,而在海藻酸钠材料表面无聚集。第三天后,海藻酸钠材料发生溶胀,纳米结构破坏,而壳聚糖纳米支架保持完好。在观察期间,PLGA材料表面一直没有肝细胞黏附。肝脏细胞不能在PLGA纳米材料表面黏附生长;壳聚糖具有良好的生物相容性,且肝细胞在壳聚糖纳米材料表面能形成球形聚集体;海藻酸钠生物相容性好,但机械稳定性差,容易降解,不能单独作为肝脏组织工程的纳米支架材料。     

纳米尿激酶的性状研究

背景：尿激酶半衰期短,需持续大量给药,并发症也不小,故有必要研制具有缓释作用的溶栓药物。 目的：了解包载尿激酶的水溶性壳聚糖纳米粒子的性状。 方法：将壳聚糖和三聚磷酸钠以离子凝集法制备尿激酶纳米粒子后,用透射电镜观察其形态,采用粒径仪测纳米粒子粒径,酶标仪比色法测粒子包封率,纳米粒子冻干法测其载药量,并检测体内外纳米粒子缓释特性。 结果与结论：当壳聚糖、三聚磷酸钠、尿激酶的质量比为7∶1∶1时,不仅溶液稳定,形成的纳米粒子粒径小,而且包封率和载药量均合适。制备出包封率最高达94.8%的尿激酶纳米粒子,载药量为14.5%,此时平均粒径236 nm,透射电镜观察示粒子形态较规则,呈球形;粒子具有较好的缓释性能;表明将尿激酶包被于纳米粒子中,避免了消化酶的直接作用,延长了半衰期,不仅在体内能保持较长时间的活性,而且具有明显的缓释效果。     

溶胶-凝胶法制备纳米羟基磷灰石粉体的研究进展

目的利用溶胶-凝胶法制备纳米羟基磷灰石粉体的方法进行研究.方法综述了溶胶-凝胶法的基本原理和分类,介绍了制备纳米羟基磷灰石粉体采用的溶胶-凝胶方法,提出了相关待解决的问题.结果溶胶-凝胶法的研究已取得一定的进展.结论利用该方法有望制备出形状可控、粒度均匀的纳米羟基磷灰石粉体.     

纳米胶体金最佳标记条件的一种简易方法研究

免疫胶体金稳定性的关键因素在于标记胶体金时条件的选择。本文将最适pH值和最适蛋白稳定量的测定结合起来,用蛋白质过量法测定胶体金最佳标记条件。     

顺磁纳米铁核素治疗的放射性剂量率比较研究

目的:探讨放射源顺磁纳米铁核素(PNINs)肿瘤内照射治疗时,源的分布状态对疗效产生的影响。方法:对放射源PNINs在被外磁场靶向在肿瘤区域以均匀状态分布和直接瘤内注射以点源状态分布在肿瘤中心处时,两种不同分布状态的剂量率进行比较研究。结果:采取瘤内注射的方法使得PNINs以点源的形式作用在肿瘤中心的方式其最大作用距离为0.53 cm,其有效杀伤距离还会小于0.53 cm;若肿瘤若肿瘤半径大于0.53 cm则应该考虑采取用外磁场靶向的方法使得PNINs以平均分布于肿瘤整个区域的方式来获得较好的疗效。结论:其比较结果为PNINs的临床运用提供有益的理论参考。     

新型银纳米颗粒涂层薄膜材料的制备与抗菌性研究

目的制备银纳米颗粒涂层薄膜材料并检测其抗菌性。方法利用脉冲激光沉积法（PLD）将银-二氧化硅薄膜种植在衬底硅片表面,根据不同的激光脉冲沉积速率制备3组薄膜材料样品,其银与二氧化硅的含量比分别为1：3（TypeA）、1：1（TypeB）、3：1（TypeC）设为实验组,纯硅片设为对照组。使用扫描电子显微镜（SEM）、能量色散光谱仪（EDS）、原子力显微镜（AFM）对实验组样品进行物理表征,选用临床标准菌株金黄色葡萄球菌和大肠杆菌作为实验菌株进行样品体外抗菌试验。结果制备的3种样品TypeA、TypeB和TypeC应用EDS测定银纳米颗粒的含量分别为19．29％、65．32％、77．18％。SEM显示,实验组样品中银纳米颗粒镶嵌于二氧化硅的骨架结构中,结构清晰。AFM显示3种样品TypeA、TypeB和TypeC表面粗糙度良好,银纳米颗粒的大小分别为10．8、11．9和12．9nm。抗菌实验显示,接种大肠杆菌的培养基中3种样品TypeA、TypeB和TypeC的抑菌环直径分别为11、15、16mm,接种金黄色葡萄球菌的培养基中3种样品的抑菌环直径分别为15、16、17mm,所制备的银纳米颗粒涂层薄膜材料均显示出抑菌作用;对照组没有出现抑菌环。结论应用PLD方法制备银纳米颗粒抗菌薄膜材料简单易行,且材料具有良好的抑菌作用。     

HPLC与UV-VIS法测定骨修复材料复合纳米微球中左氧氟沙星的比较

目的比较高效液相色谱法(High performance liquid chromatography,HPLC)与紫外-可见分光光度计法(Ultraviolet-visible spectroscopy,UV-VIS)检测纳米微球中的左氧氟沙星,为评价可控降解骨修复材料中的药物缓释提供方法学。方法直接测定标准品左氧氟沙星,绘制两种方法的标准曲线,线性范围内选低、中、高3个浓度,计算回收率。将10个载药骨修复材料(10mm×6mm×6mm)分别浸泡于3 mL模拟体液中,1天后取样,经两种方法检测,配对t检验,比较两种方法测得的结果有无统计学差异。结果 HPLC法的线性回归方程:Y=0.0334X-0.01(r=0.9996),线性范围:(0.5~250)g/mL。UV-VIS法的线性回归方程为:Y=0.06588X+0.01669(r=0.9999),线性范围:(0.5~50)g/mL。HPLC法在低、中、高浓度的回收率分别为:(96.33±0.58)%、(111.00±0.00)%、(105.00±0.00)%,RSD分别为0.37%、0.17%、0.06%;UV-VIS法的回收率分别为:(96.00±2.00)%、(99.00±0.00)%、(98.66±0.00)%,RSD分别为1.34%、0.00%、0.03%。HPLC法测得的平均浓度为:(30.43±10.27)μg/mL;UV-VIS法测得的平均浓度为:(187.93±33.52)μg/mL。两种方法测得的结果有显著统计学差异(t=20.169,P=0.000)。结论 HPLC法专属性强、回收率高、精确度高,是评价纳米微球载左氧氟沙星可控降解骨修复材料中药物缓释的理想方法。     

A comparative study of four different bronchial challenge tests

Haugaard L, Iversen M, Dahl R. A comparative study of four different bronchial challenge tests.
The correlation between 4 commonly used tests for assessment of airway hyperresponsiveness was studied in 10 asthmatics by performing bronchial challenges with histamine, ultrasonically nebulised distilled water (UNDW), exercise, and a relevant allergen. All tests were performed within 4 weeks for each individual and at least 48 h apart. A significant correlation was found between histamine challenge and exercise challenge (r=−0.74). Other correlations were substantial (0.4–0.5) but did not reach statistical significance. This suggests that the challenges have different mechanisms or pathways leading to bronchoconstriction, and assessment of the pattern of individual patients' bronchial hyperresponsiveness may require application of a number of different bronchial challenge tests. For routine use histamine challenge seems the most appropriate.     

热毒宁注射液联合蒙脱石散与喜炎平联合消旋卡多曲颗粒治疗小儿病毒性肠炎临床疗效比较研究

目的 比较热毒宁注射液联合蒙脱石散与喜炎平联合消旋卡多曲颗粒治疗小儿病毒性肠炎临床疗效.方法 将我院2012年1月-2013年1月收治的90例病毒性肠炎患儿随机分为观察组与对照组,每组45例,观察组患儿接受热毒宁注射液联合蒙脱石散治疗,对照组接受喜炎平联合消旋卡多曲颗粒治疗,比较两组治疗效果及患儿腹泻、发热、呕吐消失及住院时间,记录并比较两组患儿治疗费用.结果 两组患儿治疗效果、发热消失时间比较差异无统计学意义(P＞0.05),观察组患儿腹泻、呕吐及住院时间显著低于对照组(P＜0.05),两组患儿临床治疗费用比较(P＞0.05)差异无统计学意义.结论 热毒宁注射液联合蒙脱石散治疗小儿病毒性肠炎临床疗效显著,能有效缓解患儿临床症状、缩短患儿病程,减少患儿住院时间.     

A 1-year study of salmeterol powder on pulmonary function and hyperresponsiveness to methacholine

BACKGROUND: Long-acting beta(2)-sympathomimetic agonists such as salmeterol have been proved safe and effective for the treatment of asthma. However, controversy still exists as to the appropriateness of scheduled long-term therapy with these agents. OBJECTIVE: This study assessed the degree of bronchodilation provided by treatment with salmeterol for a period of 52 weeks and evaluated bronchial hyperresponsiveness to methacholine during and after the treatment period. METHODS: Three hundred fifty-two patients with mild to moderate asthma were assessed by 12-hour serial spirometry and serial methacholine challenge tests. RESULTS: The mean area under the FEV(1) curve above baseline over 12 hours after drug at day 1 was significantly greater with salmeterol powder compared with placebo (5.06 liter hours vs 0.77 L/h) and did not change significantly over 1 year. The mean increase in the log(2) of the provocative cumulative methacholine dose producing a 20% decrease in FEV(1) (PD(20)FEV(1)) during treatment was significantly higher in the salmeterol-treated patients than in the placebo group (1.02 doubling doses vs 0.43 doubling doses at week 4, 1.06 doubling doses vs 0.41 doubling doses at week 24). At week 52 the increase from baseline in log(2)PD(20)FEV(1) was not significantly different between salmeterol and placebo (1.08 vs 0.69 doubling doses). Seven days after treatment the log(2)PD(20)FEV(1) was -0.60 doubling doses lower than baseline for salmeterol compared with 0.10 doubling doses for placebo (P =.031). Long-term salmeterol use was not associated with a deleterious effect on asthma control during and after treatment. CONCLUSION: This study demonstrates that the bronchodilator properties of salmeterol are sustained over 52 weeks and that bronchial hyperresponsiveness to methacholine is decreased to a modest degree during treatment. Clinically significant increases in hyperresponsiveness did not develop after discontinuation of salmeterol treatment.     

A preliminary study of free amino acids in the postmorten temporal cortex from Alzheimer-type dementia patients

Concentrations of free amino acids were measured in the temporal cortex of postmortem brains from four histologically verified cases with Alzheimer-type dementia (ATD) and eight histologically normal controls. The concentrations of taurine, glutamate, and γ-aminobutryic acid, which are all neurotransmitter candidates, were significantly lower in the ATD brains than in the controls. These findings suggest that the involvement of amino acid neurons in ATD cannot be ruled out.     

A comparative study of the in-vitro interaction of the Marburg virus with macrophages from different animal species]

The amplification of Marburg virus in primary cultures of peritoneal macrophages of animals with different sensitivity to infection with this virus, as well as the capacity of this virus to adsorb on macrophages were studied. Macrophages of the animals sensitive to Marburg virus were capable to support its reproduction in vitro whereas those of resistant animals were not. Macrophages of the animals with intermediate sensitivity were shown to be either completely resistant to virus reproduction or to delay it. Besides, macrophages of sensitive and insensitive animals were capable to adsorb this virus, this capacity being markedly reduced in macrophages isolated from immunized animals and those sensitive animals which developed the disease after inoculation of the virus. The authors conclude that animal susceptibility to Marburg virus in vivo correlated with the capacity of macrophages to support Marburg virus reproduction in vitro and not with the capacity of the virus to adsorb on the macrophage surface. It is suggested that the evaluation of Marburg virus amplification in macrophages could be used as a criterion for evaluation of the susceptibility of animals to this virus in vivo.     

Detection of the antibacterial effect of Nigella sativa ground seeds with water

Nigella sativa (NS) seeds have been used for medicinal purposes for centuries both as herbs and its oil. In Islam it is regarded as one of the greatest forms of healing medicine included in the medicine of prophet Mohammed. Huge number of studies have been carried out in recent years on the pharmacological effects of these seeds and also the possible relationship with their constituents. A number of these investigations emphasized the antimicrobial effect of them by using different extracts. In our study we have tried to use the normal human mechanism in digestion by using the ground seeds. A modified paper disc diffusion method was used to test the antibacterial effect of NS seeds. Clear inhibition of the growth of Staphylococcus aureus was observed by concentration of 300 mg/ml with distilled water (D.W.) as control , this inhibition was confirmed by using the positive control Azithromycin. The inhibition obtained was higher with Nigella sativa ground seeds from Hadramout (HNSGS) than with Nigella sativa ground seeds from Ethiopia (ENSGS). No inhibition was found in the growth of E.coli and Enterobacter. This was emphasized by using the positive control Ciprofloxacin. The positive inhibition may be attributed to the two important active ingredients of NS, Thymoquinone and melanin.     

Protective effect of rimexolone on cartilage damage in arthritic mice: A comparative study with triamcinolone hexacetonide

We studied the effect of the local steroid preparation rimexolone on cartilage metabolism in arthritis and normal joints. Prolonged anti-inflammatory action was evident after intraarticular injection of a single dose of 450 g into mice with monoarticular antigen-induced arthritis. Suppression of inflammation lasted for at least 21 days. A single dose of 25 g of the anti-inflammatory steroid triamcinolone hexacetonide (THA) induced comparable suppression in the initial stage of the arthritis, but the suppressive action was of shorter duration. Both drugs significantly prevented osteophyte formation, which is a characteristic feature of this type of experimental arthritis. Although chondrocyte proteoglycan (PG) synthesis in patellar cartilage was significantly suppressed upon injection in normal joints, both steroids counteracted the severe suppression of PG synthesis in arthritic joints. These data indicate that although steroids may have significant side effects on chondrocytes, the overall effect on arthritic chondrocytes is beneficial.An advantage of rimexolone over THA is its prolonged retention, which may explain its sustained anti-inflammatory action, and the lack of systemic effect.     

缺氧敏感性不同的大鼠血小板活性的比较研究

HT(Hilltop SD)缺氧敏感大鼠与普通W(Wistar)大鼠,分平原对照组与置模拟5000米高度低压舱10天的慢性缺氧组。慢性缺氧组与对照组肺动脉收缩压的均值(PAP),在HT大鼠分别为51.9±14.2与31.3±3.0mmHg,P<0.001,慢性缺氧组比对照组高65.8%;W大鼠分别为39.7±7.4与28.9±4.7mmHg,P<0.001,慢性缺氧组比对照组高37.4%。对照HT大鼠全血及肺组织5-羟色胺(5-HT)高于对照W大鼠(P<0.05)。慢性缺氧组HT大鼠血小板数增加,与对照组相比,P<0.01;全血及肺5-HT明显减少,与对照组相比,P<0.001及P<0.05;血浆TXB_2增高,与对照组相比,P<0.001;对ADP诱导血小板聚集敏感性降低。慢性缺氧组W大鼠以上指标变化与HT大鼠相似,除血小板聚集外,HT大鼠以上变化比W大鼠更明显。提示对照组两种大鼠血小板功能状态不完全相同,慢性缺氧时,HT大鼠血小板活化程度高于W大鼠,这在HT大鼠肺动脉对缺氧的增压反应敏感中可能起一定作用。     

Lymphoid and non-lymphoid cells in the adenoid of children with otitis media with effusion: a comparative study

We characterized on immuno- and enzymecytochemical level the lymphoid and non-lymphoid cells in the adenoid of children with upper respiratory tract infections (URI) and otitis media with effusion (OME) and compared these with the adenoid of children with URI without OME and with the adenoid of 'healthy' children and adults. Besides macrophages and dendritic cells we also showed the presence of MHC class II positive, ciliated, epithelial cells. These non-lymphoid cells were present in all adenoids. However, their number was less than 1% of all cells. We found no difference in lymphocyte subsets from children with URI + OME compared with those from children with URI alone. These two groups showed a significant decrease of CD8-positive (suppressor/cytotoxic) cells and a slight increase in CD22-positive B cells in comparison to 'healthy' children. No difference was found in percentages of CD4-positive (helper/inducer) cells. The localization of the lymphoid subsets in adenoids of children with URI and/or OME did not differ from those of 'healthy' children and adults.