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1.
A limited number of grafts produced in one batch is the main constrain to validate radiation sterilization dose of amnion and bone grafts according to ISO standard. The validation experiments done were according to ISO 13409 with a slight modification in sampling method. The experiments were carried out three times by using 20 samples each, 10 for bio-burden enumeration and 10 for sterility test at verification dose. The average bio-burden with sample item portion (SIP) = 1 for amnion membranes were 98, 50 and 69 cfu respectively and 0 cfu for bone grafts. Verification dose experiments, were done at doses of 2.90kGy for bone grafts and 5.13kGy for amnion grafts and the results of sterility tests showed that amnion grafts got one positive and bone grafts got 0 positive. The results met the requirements of ISO 13409 so that the radiation sterilization dose, at sterility assurance level of 10-6 was 25kGy for both amnion and bone grafts. Viral contamination was excluded in this experiment.  相似文献   

2.
Prevention of mother-to-child transmission (PMTCT) of HIV with highly active antiretroviral therapy (HARRT) allows the HIV~+ pregnant mothers to have vaginal delivery and breastfeed.Here we investigated the maternal plasma immunoglobulin,cytokine secretion and the outcome of the exposed infants among the HIV~+ HAART treated pregnan women in Nigeria.In this study,different plasma immunoglobulins and cytokines were measured in the HIV~+ HAART treated pregnant mothers.Pooled culture supernatants of B and T lymphocytes showed lower levels of IFN-γ,IL-10 and IL-4.There were lower IFN-γ and IL-10 secretions at 1st trimester;however,IL-10 continued to be lower throughout 2nd and 3rd trimesters.TNF-α secretion significantly decreased as pregnancy progressed to term.There were high plasma IgG and low IgM in the HIV~+ HAART treated pregnant women.Plasma IgG was high during 1st and 3rd trimesters.After one year of follow up,all the exposed children were seronegative for HIV-1 and HIV-2.Vaginal delivery and breastfeeding among HIV~+ HAART treated mothers have shown to be safe.The use of HAART by the infected mothers and the use of septrin and niverapin by the exposed infants prevented mother to-child transmission of HIV.  相似文献   

3.
This study was performed to determine the levels of lead (Pb) and cadmium (Cd) in 63 bone samples of the prehispanic population of the island El Hierro, comparing them with the values obtained on 98 prehispanic samples from Tenerife, Fuerteventura, Gran Canaria, and La Palma, all of them in the Canary Islands, and with eight modern samples who served as controls. Prehispanic individuals from El Hierro showed the lowest bone Pb values of all the archipelago (0.72±1.01 mg/kg), significantly different (F=6.9, p<0.001) from the values obtained for the population of other islands such as Tenerife (4.87±5.36 mg/kg) or Fuerteventura (4.45±7.85 mg/kg) and also from those of the modern population (30.53±14.62 mg/kg). On the other hand, bone Cd, although slightly lower in the ancient population groups, was not significantly different when compared with the modern one. In addition, no differences were observed in bone Cd among the ancient population of the different islands. Bone lead—but not cadmium—kept an inverse significant relationship with the distance of the burial site both to south Spain (r=−0.31) and Atlantic Morocco (r=−0.28, p<0.001 in both cases).  相似文献   

4.
以增强UV-B(10.08 kJ.m-2.d-1)辐射后的小麦根尖细胞为材料,采用间接免疫荧光标记技术,利用激光共聚焦扫描显微镜,观察分析小麦根尖分裂期细胞Ran蛋白在分裂周期的分布及形态变化。研究结果显示,正常细胞中,Ran蛋白在细胞分裂间期主要定位于核膜周边,在后期定位于赤道板上和纺锤体上,末期又回到子细胞核膜周边;增强UV-B辐射处理后,在细胞分裂间期和前期有点状荧光分布在核膜的周围;中期和后期点状荧光分布在细胞质中;在末期部分点状荧光又回到核膜的周围,部分仍分散在核内,且出现落后染色体、染色体桥、不均等分裂等染色体畸变类型和异常分裂现象。  相似文献   

5.
Humans and gorillas share 97% of their genetic makeup which means the risk of disease transmission between the two is potentially high. Humans with high exposure and whose exposure-related activity can most easily be managed are park conservation personnel. In June 2001, the Morris Animal Foundations Mountain Gorilla Veterinary Project initiated a health program for all employees working in Rwandas Parc National des Volcans in collaboration with in-country government and nongovernmental agencies. The goal is to improve the health of conservation personnel and reduce the risk of zoonotic disease transmission between employees and the parks mountain gorillas. Employees annually receive a clinical examination and laboratory testing, and provide a clinical history, In 2002, analyses were performed on the dataset of 127 employees to identify potential risk factors associated with positive laboratory tests. Considering all fecal tests combined, 70.1% were positive for one or more pathogenic organisms. A high percentage (> 80%) tested positive on viral antibody titer testing for various communicable diseases including measles, chickenpox, and hepatitis. On multivariate analysis, the main risk factor for testing positive for any pathogenic organism was use of a pit latrine at home. Vaccination against childhood communicable diseases and improved human waste disposal could be critical control points for preventing disease transmission to mountain gorillas. Program results have been shared with local health officials to aid in their efforts to improve village health and sanitation standards, and with park employers as a basis for ongoing employee health education.The Mountain Gorilla Veterinary Project 2002 Employee Health Group members are listed in Appendix 1. by area of contribution.  相似文献   

6.
采用离子对反相高效液相色谱法 ( IPr HPLC)的单液等度洗脱 ,测定了小鼠骨髓红系爆增性集落形成单位 ( BFU- Es)与红系集落形成单位 ( CFU- Es)的 PRPP合成酶活性 .方法学研究表明 ,加入离子对试剂硫酸氢四丁基铵 ( TBAHS)后 ,ADP谱峰分离完全 ,其反应增加量易于计算 .本法的批内变异系数平均值为 - 2 .30 %~ - 1 .0 6%与 1 .0 6%~ 2 .30 % ,平均相对偏差为 0 .81 %~ 1 .74% ,回收率为 93.9%~ 98.5% ,能达到操作简便、灵敏和准确的要求 .采用本法测得 2 0只正常昆明小鼠的 BFU- E和 CFU- E中该酶活性各为 ( 0 .563± 0 .0 2 7)μmol/( min·g· m L- 1)与 ( 0 .41 6± 0 .0 2 6) μmol/( min·g·m L- 1) .  相似文献   

7.
Acetylcholinesterase (EC 3.1.1.7) was inactivated photochemically in solution, in the presence of dissolved terthiophene sensitizers. Alpha-terthienyl (2,2′:5,2″-terthiophene) and its isomers 3,2′:5′,2″- and 3,2′:5′,3″-terthiophenes showed very similar sensitizing properties. With all three terthiophenes, the photosensitization was completely suppressed under anaerobic conditions, and therefore the inactivation process required the presence of oxygen. The enzyme was inactivated in vivo when fourth instar larvae of the mosquito Aedes aegypti were treated with alpha-terthienyl in the presence of long-wavelength ultraviolet light. No inactivation was observed when the organisms were treated with the ultraviolet light alone, with the chemical alone, or with a previously irradiated sample of the chemical. This paper represents the first example of acetylcholinesterase inactivation in vivo by a photoactive insecticide.  相似文献   

8.
Osteoclasts (OCL) resorb bone. They are essential for the development of normal bones and the repair of impaired bones. The function of OCL is presumed to be supported by cytokines and other biological mediators, including tumor necrosis factor (TNF)-α and nitric oxide (NO). Bacterial lipopolysaccharide (LPS) is a potent inducer of TNF-α and inducible nitric oxide synthase (iNOS), which is the specific enzyme for synthesizing NO from L-arginine. To obtain direct evidence on LPS-induced TNF-α production and iNOS expression by OCL, OCL-enriched cultures were prepared by 7-day cocultures of bone marrow cells of adult BALB/c mice and osteoblastic cells (OBs) derived from calvaria of newborn BALB/c mice, and the generation of TNF-α and iNOS in OCL stimulated with LPS was examined immunocytochemically. When the cultured cells were stimulated with 100 ng/ml of LPS, OCL clearly showed TNF-α and iNOS expression. Without LPS-stimulation, no expression was observed. TNF activity in the culture supernatants of the OCL-enriched cultures in the presence of LPS was also detected by cytotoxic assay that used TNF-sensitive L929 cells. The dentin resorption activity of OCL was estimated by area and number of pits formed on dentin slices, which were covered by the OCL fraction and cultured in the presence or absence of LPS, sodium nitroprusside (SNP; a NO generating compound), NG-monomethyl L-arginine acetate (L-NMMA; a competitive inhibitor of NO synthase (NOS)), or LPS plus L-NMMA. Pit formation was obviously inhibited in the presence of SNP and slightly inhibited in the presence of L-NMMA, but it was not affected in the presence of LPS or LPS plus L-NMMA. These findings indicate that OCL produces TNF and expresses iNOS in response to LPS, but the LPS-activation of OCL scarcely affects pit formation by them.  相似文献   

9.
We studied the effects of irradiation with X-rays (the total dose of 0.0129 C/kg was attained over 7, 14, or 21 days), increased entry of Al3+ into the organism (0.2% AlCl3 in drinking water), and the combined influence of these factors for 21 days on the contents of the soluble and filamentous forms of glial fibrillary acidic protein (GFAP) in the tissues of the hippocampus, cerebellum, and neocortex of albino rats. After irradiation for 7 days, a clear trend toward drops in the GFAP contents in the structures under study was observed, while irradiation in the same dose, but for 14 or 21 days, resulted in increases in the contents of both GFAP forms (within a range of 13-29%, as compared with the control). Entry of aluminum chloride with water also resulted in an increase in the GFAP contents in all studied structures; changes in the filamentous form were more intensive. The combined influence of irradiation and Al3+ resulted in more intensive shifts in the GFAP levels; the content of its filamentous form increased in all structures by about 50%, while shifts of the soluble form were somewhat smaller.  相似文献   

10.
中华按蚊是我国北纬25度以北地区传播疟疾的重要媒介。温度是影响按蚊繁殖和疟原虫发育的主要生态因子,对疟疾流行季节与流行程度影响甚大。本文从温度与中华按蚊各虫态发育历期的关系,分析不同纬度地区中华按蚊  相似文献   

11.
目的:研究腹腔镜微创技术联合频谱照射治疗小儿阑尾炎的疗效及对血清可溶性细胞间粘附分子1(Soluble intercellular adhesion molecule-1,slCAM-1)、降钙素(Calcitonin,PCT)水平的影响。方法:选取2016年2月~2018年2月我院收治的87例小儿阑尾炎患者。按照简单随机数表法将其分为观察组(n=42)和对照组(n=45),对照组采用传统手术治疗,观察组采用腹腔镜微创技术联合频谱照射治疗。观察和比较两组治疗后手术指标(手术时间、术中出血量、住院时间),肠功能恢复情况(肠鸣音恢复时间、肛门排气时间、首次排便时间),治疗前后血清slCAM-1、PCT水平的变化及不良反应的发生情况。结果:治疗后,观察组手术时间、术中出血量、住院时间显著低于对照组[(47.82±8.33)min vs (56.97±10.46)min,(46.97±9.75)mL vs (90.72±13.86)mL,(7.02±2.41)d vs(11.84±3.58)d](P0.05);肠鸣音恢复时间、肛门排气时间、首次排便时间显著低于对照组[(19.38±4.32)h vs (25.82±6.18)h,(16.98±4.59)h vs (36.83±7.29)h,(32.02±5.82)h vs (40.17±7.60)h](P0.05);血清slCAM-1、PCT水平显著低于对照组[(180.27±23.75)ng/L vs (197.06±27.30)ng/L (0.92±0.20)ng/L vs (3.87±1.03)ng/L](P0.05);不良反应总发生率显著低于对照组[7.14%(3/42) vs 22.22%(10/45)](P0.05)。结论:腹腔镜微创技术联合频谱照射治疗小儿阑尾炎疗效显著,可改善微循环,促进肠功能恢复,降低血清slCAM-1、PCT水平,并发症少,有利于术后恢复。  相似文献   

12.
A longitudinal study was conducted to investigate the relation between a polymorphism in the vitamin D receptor (VDR) gene and changes in bone mineral density (BMD) and quantitative ultrasound of the phalanges (QUS) over a five-year period. The subjects were 456 postmenopausal women with osteoporosis undergoing treatment, aged 59.95±7.97 years (mean±standard deviation [SD]) at baseline. BMD was measured at the hips and lumbar spine by dual-energy X-ray absorptiometry, and QUS was measured by means of amplitude-dependent speed of sound (Ad-SoS) at the phalanges. Lifestyle information was obtained via a questionnaire. The genotype frequencies of the BsmI (rs1544410) gene polymorphism were 29.4%, 47.1%, and 23.5% for bb, Bb, and BB, respectively. After five years, BMD (annual change in %/year) at the femoral neck (FN) showed a significant modification based on the rs1544410 genotype (BB vs Bb); there was an overall decrease in bone mass (-0.70±2.79%/year; P = 0.025). An analysis of covariance with adjustments for age, weight, height, percentage of weight change per year, baseline BMD and calcium intake showed that the observed associations were no longer significant (P = 0.429). No significant associations were found between the QUS measurements and the rs1544410 genotype after the five-year period. Our study limitations includes lack of information about type and length of duration of the osteoporosis treatment. Our results indicate that rs1544410 polymorphisms do not account significantly for the changes in bone mass in Spanish women with osteoporosis undergoing treatment.  相似文献   

13.
14.
Abstract This work deals with the impact of a possible accidental pollutant, pyralene (Prodelec, France; PCBs in trichlorobenzene), intoduced into the soil. Its influence on the predator-prey relation between bacteria and amoebae was studied by comparing the population dynamics of (i) an inoculated bacterial population ( A. lipoferum ) chosen as a biological tracer, (ii) the indigenous bacterial microflora, (iii) the infigenous amoebae. In the absence of pyralene the inoculated bacterial population decreased from 107 to 104 bacteria g−1 soil (dw), grazed by the infigenous amoebae whose numbers increased 3-fold. In contrast, in presence of 2500 ppm of pyralene the introduced bacteria survived at a higher level (3·106 bacteria g−1 soil (dw)) while the number of amoebae diminished slightly. No predation occurred with PCB contamination. The indigenous bacterial microflora was not affected quantitatively by pyralene. In pure liquid culture with 500 ppm of pyralene added, bacterial growth was inhibited and an amoebal strain isolated from an inoculated uncontaminated soil was killed. We conclude that the active form of the amoebae were killed, and encystement was inhibited by pyralene in the soil. Hence the protozoa were unable to regulate the introduced A. lipoferum strain as they did in the absence of the pollutant.  相似文献   

15.
Summary The effect of increasing potassium and magnesium fertilization during 15 years on the amounts of K and Mg extracted by AL-solution and desorbed by Electro-Ultrafiltration (EUF) was determined in four Swedish soils. In all soils, with increasing potassium fertilization the amounts of K extracted by AL and desorbed by EUF increased, and the amounts of Mg-AL and Mg-EUF decreased. Magnesium fertilization had no significant effect on the K values but increased both Mg-AL and Mg-EUF. The EUF-values were lower than the corresponding AL-values, but the ratio of EUF-desorbed to AL-extracted amounts of K and Mg varied depending on soil type as well as on fertilization rate. The ratio of K-EUF to K-AL increased and the ratio of Mg-EUF to Mg-AL decreased with increasing potassium fertilization, whereas magnesium fertilization decreased the ratio of Mg-EUF to Mg-AL.  相似文献   

16.
We calculated the three‐dimensional optical stress distribution and the resulting deformation on a biconcave human red blood cell (RBC) in a pair of parallel optical trap. We assumed a Gaussian intensity distribution with a spherical wavefront for each trapping beam and calculated the optical stress from the momentum transfer associated with the reflection and refraction of the incident photons at each interface. The RBC was modelled as a biconcave thin elastic membrane with uniform elasticity and a uniform thickness of 0.25 μm. The resulting cell deformation was determined from the optical stress distribution by finite element software, Comsol Structure Mechanics Module, with Young's modulus (E) as a fitting parameter in order to fit the theoretical results for cell elongation to our experimental data. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

17.
18.
Solvent relaxation (SR) in 1,2-dioleoyl-palmitoyl-sn-glycero-3-phosphocholine (DOPC) unilamellar vesicles of different size was probed by 6-hexadecanoyl-2-(((2-(trimethylammonium)ethyl)methyl)amino)naphthalene chloride (Patman), 6-propionyl-2-dimethylaminonaphthalene (Prodan) and 4-[(n-dodecylthio)methyl]-7-(N,N-dimethylamino)-coumarin (DTMAC). Patman probes the amount and mobility of the bound water molecules located at the carbonyl region of the bilayer. Membrane curvature significantly accelerates the solvent relaxation process, but does not influence the total Stokes shift, showing that membrane curvature increases the mobility, without affecting the amount of water molecules present in the headgroup region. This pattern was also verified for other phosphatidylcholines. Prodan is located in the phosphate region of the bilayer and probes a more polar, mobile and heterogeneous environment than Patman. The influence of membrane curvature on SR probed by Prodan is similar, however, less pronounced compared to Patman. DTMAC (first time used in SR) shows a broad distribution of locations along the z-axis. A substantial amount of the coumarin chromophores face bulk water. No effect of curvature on SR probed by DTMAC is detectable.  相似文献   

19.
微水相中杏仁醇腈酶催化不对称合成(R)-氰醇的研究   总被引:1,自引:0,他引:1  
利用气相色谱手性分析,研究了微水相中来源于杏仁的(R)-醇腈酶催化醛与HCN不对称合成(R)-氰醇.结果表明,反应时间、添加乙酸、反应介质、反应体系水活度、反应温度和底物的结构对醇腈酶反应均有显著影响.杏仁醇腈酶对芳香族、脂肪族和杂环族醛均有良好的催化作用.其中,苯甲醛为杏仁醇腈酶的最适作用底物,在低温(0~5℃)下,转化率和产物对映体过剩值均在99%以上.  相似文献   

20.
Poly(amidoamine) (PAMAM) dendrimers are promising nanocarriers that can enhance the solubility of hydrophobic drugs. The surface chemistry of dendrimers is of great relevance as end groups of these nanocarriers can be easily modified to improve the bioavailability and sustained release of the cargo. Therefore, a molecular‐level understanding of the host‐guest interactions that can give both qualitative and quantitative information is particularly desirable. In this work, fully atomistic molecular dynamics simulations were used to study the association of a bioactive natural product, ie, chalcone, with amine‐, acetyl‐, and carboxyl‐terminated PAMAM dendrimers at physiological and acidic pH environments. Amine‐ and carboxyl‐terminated PAMAM dendrimers have an open microstructure at low pH that is not able to hold the ligand tightly, resulting in an unfavorable encapsulation of the chalcone molecule. In the case of acetyl‐terminated dendrimer, chalcone molecule diffuses out of the dendritic cavities a few times during the simulation time and prefers to locate close to the surface of dendrimer. Average center of mass distance values at neutral pH showed that the chalcone molecule bounds firmly in the internal pockets of amine‐, acetyl‐, and carboxyl‐terminated dendrimers and forms stable complexes with these nanovectors. The potential of mean force calculations showed that the release of the ligand from the dendrimers occurs at a controlled rate in the body.  相似文献   

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