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61.

Background

Gold nanoparticles now command a great deal of attention for medical applications. Despite the importance of nano-bio interfaces, interaction between peptides and proteins with gold surfaces is not still fully understood, especially in a molecular level.

Methods

In the present study computational simulation of adsorption of 20 amino acids, in three forms of mono-amino acid, homo di-peptide and homo tri-peptide, on the gold nanoparticles was performed by Gromacs using OPLSAA force field. The flexibility, stability, and size effect of the peptides on the gold nanoparticles were studied as well as the molecular structure of them.

Results

According to our results, adsorbed homo tri-peptides on the gold surface had more flexibility, more gyration, and the farthest distance from the GNP in comparison with homo di-peptides and mono-amino acids.

Conclusion

Our findings provide new insights into the precise control of interactions between amino acids anchored on the GNPs.
  相似文献   
62.
Ocular lesions are frequently associated with different parasitic infections. The classes of infection include protozoa, nematodes, cestodes, and ectoparasites. Ocular parasitic infections can manifest in any part of the eye; the disease manifestations are frequently characterized as either posterior or anterior eye disease. Parasite-induced lesions may be due to damage directly caused by the parasite, indirect pathology caused by toxic products or the immune response initiated by infectious parasitism. This review characterized the parasite-induced lesions in the posterior segment of the eye. Prompt diagnosis and early treatment of these lesions can reduce ocular morbidity. The method of the literature search was conducted on PubMed, Elsevier Scopus database, and Google Scholar with no limitation on the year of publication databases. It was limited to English articles published for ocular lesions in clinical studies and was focused on parasitic infections of the eye.  相似文献   
63.
目的:研究埃及Tanta大学医院与隐形眼镜相关的感染性角膜炎患者的不同流行病学特点,评估这类疾病各方面的特点,以提高患者对这类疾病的认识,找出可行的解决方案。

方法:选取我院2009-01/2013-12期间在眼科门诊就诊的所有角膜炎患者仔细检查,并对所有与隐形眼镜相关的感染性角膜炎患者进一步检查和调查。

结果:本研究期间,总共108 496位有不同主诉的患者中,1463例(1.3%)患有不同形式的角膜炎,其中151例(0.1%)为隐形眼镜相关感染性角膜炎。结果发现患有隐形眼镜相关感染性角膜炎常见的年龄群<30岁,大多数是学生(64%),家庭人数多且较为拥挤,农村居民高于城市居民,患者采用户外水源及污水处理不卫生。从病史分析发现:隐形眼镜相关感染性角膜炎通常为彻夜使用,储存或者配戴不卫生,或者隐形眼镜来源不安全,例如化妆品商店和理发店。结膜囊微生物培养结果提示阳性率92%,阴性率8%。大多数培养阳性的病例是由细菌和真菌混合感染引起,共53例(38.1%),单纯细菌感染43例(30.9%),真菌31例( 22.3%),阿米巴12例(8.6%)。

结论:与隐形眼镜相关的感染性角膜炎常见于学生群体,与农村生活、户外供水、不卫生的污水处理等危险因素有关。彻夜配戴、储存或配戴不卫生及隐形眼镜来源不安全都可增加隐形眼镜相关感染性角膜炎的发病率。  相似文献   

64.
Background: Microsporidia species are obligatory intracellular agents that can infect all major animal groups including mammals, birds, fishes and insects. Whereas worldwide human infection reports are increasing, the cognition of sources of infection particularly zoonotic transmission could be helpful. We aimed to detect zoonotic microsporidia spore in fecal samples from some animals with close – contact to human. Methods: Overall, 142 fecal samples were collected from animals with closed-contact to human, during 2012-2013. Trichrome – blue staining were performed and DNA was then extracted from samples, identified positive, microscopically. Nested PCR was also carried out with primers targeting SSU rRNA gene and PCR products were sequenced. Results: From 142 stool samples, microsporidia spores have been observed microscopically in 15 (10.56%) samples. En. cuniculi was found in the faces of 3 (15%) small white mice and 1 (10%) laboratory rabbits(totally 2.81%). Moreover, E. bieneusi was detected in 3 (10%) samples of sheep, 2 (5.12%) cattle, 1 (10%) rabbit, 3 (11.53%) cats and 2 (11.76%) ownership dogs (totally 7.74%). Phylogenetic analysis showed interesting data. This is the first study in Iran, which identified E. bieneusi and En. Cuniculi in fecal samples of laboratory animals with close – contact to human as well as domesticated animal and analyzed them in phylogenetic tree. Conclusion: E. bieneusi is the most prevalent microsporidia species in animals. Our results can also alert us about potentially zoonotic transmission of microsporidiosis.Key Words: Laboratory animals, Enterocytozoon bieneusi, Encephalitozoon cuniculi, Zoonotic transmission  相似文献   
65.

Background:

Free-living amoebae belonging to the genus Acanthamoeba have an environmental distribution. Amoebic keratitis due to these protozoan parasites continue to rise in Iran and worldwide. In Iran, there are various researches regarding both morphological and molecular identification of Acanthamoeba spp. in environmental and clinical samples. However, there is no thorough review about Acanthamoeba genotypes and their distribution in environmental sources such as water, dust and biofilm in Iran. Besides, according to increasing cases of Amoebic keratitis in the region awareness regarding the pathogenic potential of these sight-threatening amoebae is of utmost importance.

Methods:

We conducted a thorough review based on the database sources such as MEDLINE, PubMed and Google scholar. No restrictions were placed on study date, study design or language of publication. We searched all valuable and relevant information considering the occurrence of the Acanthamoeba in both environmental and clinical samples.

Results:

According to our thorough review Acanthamoeba belonging to T4 genotype is the most prevalent type strain in environmental and clinical samples in several regions in Iran and worldwide, however, there are reports regarding Acanthamoeba belonging to other genotypes such as T2, T3, T5, T6 and T11 and the mentioned point could leads us to more researches with the goal of presenting the real genotype dominance of Acanthamoeba and related disease in the country.

Conclusion:

Overall, the present review will focus on present status of genotypes of Acanthamoeba in Iran during recent years.  相似文献   
66.
67.
Clinical Rheumatology - To investigate the characteristics, evolution, and visual outcome of non-infectious uveitis. Records of 201 patients with non-infectious uveitis (136 (67.7%) males and 84...  相似文献   
68.
Growth differentiation factor 15 (GDF15) plays an important role in cancer pathophysiology and prognosis. However, limited studies analyzed its level and prognostic value in acute myeloid leukemia (AML) patients. This study included 56 adult AML patients. Serum GDF15 level was measured at diagnosis in all patients by enzyme-linked immunosorbent assay. Remission and survival statuses were assessed at 90 days following treatment. GDF15 level was significantly higher in patients than in controls (P < 0.001). GDF15 level correlated positively with age (P < 0.001), hemoglobin level (P = 0.027), and platelet count (P = 0.024). High GDF15 above the median level was associated with inferior OS (P = 0.044) together with high platelet count (P = 0.006) and high bone marrow blast percent (P = 0.038). There was no statistically significant difference between patients with GDF15 above and below the median level regarding DFS (P = 0.881). On multivariate analysis for OS, GDF15 level was an independent risk factor (P = 0.047). In conclusion, serum GDF15 level is significantly elevated in AML patients and high GDF15 level is associated with inferior OS.  相似文献   
69.
AIDS and Behavior - Injection drug use has been the leading route of HIV transmission in Iran. We assessed HIV prevalence, risk behaviors, and uptake of prevention services among people who inject...  相似文献   
70.

Purpose

“Endometriosis” is defined such as the presence of endometrial glands and stroma outside the uterine cavity. This ectopic condition may develop as deeply infiltrating endometriosis (DIE) when a solid mass is located deeper than 5 mm underneath the peritoneum including the intestinal wall. The ideal surgical treatment is still under search, and treatment may range from simple shaving to rectal resection. The aim of the present systematic review is to report and analyze the postoperative outcomes after rectosigmoid resection for endometriosis.

Methods

We performed a systematic review according to Meta-analysis of Observational Studies in Epidemiology guidelines. The search was carried out in the PubMed database, using the keywords: “rectal resection” AND “endometriosis” and “rectosigmoid resection” AND “endometriosis.” The search revealed 380 papers of which 78 were fully analyzed.

Results

Thirty-eight articles published between 1998 and 2017 were included. Three thousand seventy-nine patients (mean age 34.28?±?2.46) were included. Laparoscopic approach was the most employed (90.3%) followed by the open one (7.9%) and the robotic one (1.7%). Overall operative time was 238.47?±?66.82. Conversion rate was 2.7%. In more than 80% of cases, associated procedures were performed. Intraoperative complications were observed in 1% of cases. The overall postoperative complications rate was 18.5% (571 patients), and the most frequent complication was recto-vaginal fistula (74 patients, 2.4%). Postoperative mortality rate was 0.03% and mean hospital stay was 8.88?±?3.71 days.

Conclusions

Despite the large and extremely various number of associated procedures, rectosigmoid resection is a feasible and safe technique to treat endometriosis.
  相似文献   
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