831 research outputs found
Controlled synthesis and characterization of hollow flower-like silver nanostructures
Kamel AM Eid, Hassan ME AzzazyNovel Diagnostics and Therapeutics Group, Yousef Jameel Science and Technology Research Center, School of Sciences and Engineering, The American University in Cairo, New Cairo, EgyptBackground: The synthesis of anisotropic silver nanoparticles is a time-consuming process and involves the use of expensive toxic chemicals and specialized laboratory equipment. The presence of toxic chemicals in the prepared anisotropic silver nanostructures hindered their medical application. The authors have developed a fast and inexpensive method for the synthesis of three-dimensional hollow flower-like silver nanostructures without the use of toxic chemicals.Methods: In this method, silver nitrate was reduced using dextrose in presence of trisodium citrate as a capping agent. Sodium hydroxide was added to enhance reduction efficacy of dextrose and reduce time of synthesis. The effects of all four agents on the shape and size of silver nanostructures were investigated.Results: Robust hollow flower-like silver nanostructures were successfully synthesized and ranged in size from 0.2 µm to 5.0 µm with surface area between 25–240 m2/g. Changing the concentration of silver nitrate, dextrose, sodium hydroxide, and trisodium citrate affected the size and shape of the synthesized structures, while changing temperature had no effect.Conclusion: The proposed method is simple, safe, and allows controlled synthesis of anisotropic silver nanostructures, which may represent promising tools as effective antimicrobial agents and for in vitro diagnostics. The synthesized hollow nanostructures may be used for enhanced drug encapsulation and sustained release.Keywords: silver nanoparticles, 3D hollow, flower-like, green synthesi
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Comparison between the outcome of single versus multiple uterine fibroids after uterine artery embolization
Background
Uterine fibroids are the most common benign tumor of the reproductive tract in women. Uterine artery embolization has been approved as an alternative treatment option for uterine fibroids to reduce uterine and fibroid volumes as well as to relieve the patient symptoms. The current study included 80 patients with symptomatic uterine fibroids. All patients underwent pre-embolization MRI, uterine artery embolization, and follow-up post-embolization MRI at 6 months post procedure for a reduction in uterine and dominant fibroid volumes. The aim of the study was to assess the role of transcatheter uterine artery embolization in reducing the uterine fibroid volume.
Results
There was a significant difference in the uterine volume reduction between a group with single fibroids and a group with multiple uterine fibroids The mean uterine volume reduction in the first group was 46.5% compared to 37.4% reduction in the second group. While there was no significant difference in the dominant fibroid volume reduction between both groups (48.8% and 44.9% respectively).
Conclusions
UAE has a high efficacy in the reduction of both the uterine volume and the dominant fibroid volume, which results in improvement in patient’s quality of life
Association between the polymorphisms of angiotensin converting enzyme (Peptidyl-Dipeptidase A) INDEL mutation (I/D) and Angiotensin II type I receptor (A1166C) and breast cancer among post menopausal Egyptian females
Renin angiotensin system (RAS) is involved in the regulation of cardiovascular homeostasis. Angiotensin (Ang II) is converted from angiotensin I via angiotensin converting enzyme (ACE). Ang II exerts its effects by binding to two types of receptors; AT1R and AT2R. Ang II effect on AT1R promotes proliferation, angiogenesis and metastasis in breast tissues. ACE (I/D) polymorphism is an insertion/deletion of a 287 bp DNA fragment within intron 16 of ACE gene. A1166C is a single nucleotide polymorphism (SNP) in the 30-UTR of AT1R gene. Both (D) and (C) alleles were found to be related to RAS overactivation.Subjects and methods: One hundred and twenty postmenopausal Egyptian females were included in the present study and were divided into control group (fifty apparently healthy women) and patients group (seventy breast cancer patients). Detailed history taking was done with stress on age, family history, menstrual, obstetric, medical and drug history. Physical examination including body mass index calculation was done. Histopathological examination was done for tumor grading and staging. Detection of ACE gene (I/D) polymorphism by PCR and AT1R A1166C SNP using PCR/RFLP were done. Results: A statistically significant difference in AT1R A1166C SNP genotype frequencies was found among the studied groups. The patients group showed higher frequency of ‘‘CC’’ (2.9% vs 0%) and ‘‘AC’’ (44.3% vs 24%) and lower frequency of ‘‘AA’’ genotype (52.9% vs 76%) than controls. The patients also showed significant higher frequency of allele ‘‘C’’ (25% vs 12%) which was associated with increased breast cancer risk with an Odds ratio of 2.4444 (95% CI: 1.1967– 4.9931). Testing the dominant model of inheritance revealed a statistically higher frequency of exposed genotypes ‘‘AC and CC’’ among the patients group (47.1% vs 24%, respectively; p= 0.013) with substantial increase in breast cancer risk among the exposed genotypes with an Odds ratio of 2.8243 (95% CI: 1.2679–6.2913). The present study demonstrated that (AC and CC) genotypes of AT1R A1166C SNP and increased BMI can be considered as predictors for breast cancer risk among post menopausal Egyptian females. Results also revealed that A1166C SNP of AT1R gene and ACE/ID polymorphism could not be considered as predictors for breast cancer prognosis.KEYWORDS Breast neoplasm; INDEL mutation; Renin-angiotensin system; Peptidyl-Dipeptidase A
Lack of association of CTLA-4 +49 A/G polymorphism with predisposition to type 1 diabetes in a cohort of Egyptian families
Background: Type 1 diabetes is one of the most common chronic childhood illnesses. Interplay between genetic susceptibility and environmental factors is thought to provide the fundamental element for the disease. Apart from the Major Histocompatibility locus which is the main contributor to risk susceptibility, more than 40 loci are recognized. One among these is the CTLA-4, however data from the literature are controversial. The aim of our study was to investigate the role of CTLA4 49 A/G as a risk susceptibility factor for the development of type 1 diabetes in a cohort of Egyptian families.Subjects and methods: This is a case control study including 88 Egyptian families with one or more index cases (<18 years). The control group comprised 369 healthy unrelated subjects with no family history of diabetes or autoimmune disease. Using PCR-RFLP methodology, CTLA4 49 A/G was analyzed in 738 samples representing 88 families (88 patients, 125 siblings and 156 parents) and 369 control.Results: The age of onset was 6 days-12.5 years with a mean of 5.3± 3.6 and a median of 5 years. The mode of presentation was classic symptoms in 51 and diabetic ketoacidosis in 37 cases. Twenty-two cases had a history of viral infection or exanthematous disease and four had associated autoimmune diseases. No significant differences were encountered between the different groups with regard to CTLA4 +49 A/G genotype or allele frequencies. Neither was there a relation between the various genotypes and age of onset or the mode of presentation.Conclusions: CTLA4 49 A/G polymorphism was not recognized as a risk susceptibility factor in our cohort. This may be attributed to the low co-incidence of autoimmune diseases. Up to our best knowledge, this is the first study involving families. We recommend that all studies performed on risk susceptibility to type 1 diabetes should include proper investigation for other autoimmune diseases to exclude their confounding effect on data analysis.Keywords: Type 1 diabetes; CTLA-4; Risk susceptibilit
A flavonoid-rich fraction of Euphorbia peplus attenuates hyperglycemia, insulin resistance, and oxidative stress in a type 2 diabetes rat model
Background: Type 2 diabetes (T2D) is a metabolic disorder characterized by insulin resistance (IR) and hyperglycemia. Plants are valuable sources of therapeutic agents for the management of T2D. Euphorbia peplus has been widely used as a traditional medicine for the treatment of various diseases, but its beneficial role in T2D has not been fully explored. Methods: The anti-diabetic efficacy of E. peplus extract (EPE) was studied using rats with T2D induced by high-fat diet (HFD) and streptozotocin (STZ). The diabetic rats received 100, 200, and 400 mg/kg EPE for 4 weeks. Results: Phytochemical fractionation of the aerial parts of E. peplus led to the isolation of seven known flavonoids. Rats with T2D exhibited IR, impaired glucose tolerance, decreased liver hexokinase and glycogen, and upregulated glycogen phosphorylase, glucose-6-phosphatase (G-6-Pase), and fructose-1,6-bisphosphatase (F-1,6-BPase). Treatment with 100, 200, and 400 mg/kg EPE for 4 weeks ameliorated hyperglycemia, IR, liver glycogen, and the activities of carbohydrate-metabolizing enzymes. EPE attenuated dyslipidemia, serum transaminases, tumor necrosis factor (TNF)-α, interleukin (IL)-1β and liver lipid accumulation, nuclear factor (NF)-κB p65, and lipid peroxidation, nitric oxide and enhanced antioxidants. All EPE doses upregulated serum adiponectin and liver peroxisome proliferator-activated receptor γ (PPARγ) in HFD/STZ-induced rats. The isolated flavonoids showed in silico binding affinity toward hexokinase, NF-κB, and PPARγ. Conclusion: E. peplus is rich in flavonoids, and its extract ameliorated IR, hyperglycemia, dyslipidemia, inflammation and redox imbalance, and upregulated adiponectin and PPARγ in rats with T2D
Tumor markers in breast cancer - European Group on Tumor Markers recommendations
Recommendations are presented for the routine clinical use of serum and tissue-based markers in the diagnosis and management of patients with breast cancer. Their low sensitivity and specificity preclude the use of serum markers such as the MUC-1 mucin glycoproteins ( CA 15.3, BR 27.29) and carcinoembryonic antigen in the diagnosis of early breast cancer. However, serial measurement of these markers can result in the early detection of recurrent disease as well as indicate the efficacy of therapy. Of the tissue-based markers, measurement of estrogen and progesterone receptors is mandatory in the selection of patients for treatment with hormone therapy, while HER-2 is essential in selecting patients with advanced breast cancer for treatment with Herceptin ( trastuzumab). Urokinase plasminogen activator and plasminogen activator inhibitor 1 are recently validated prognostic markers for lymph node-negative breast cancer patients and thus may be of value in selecting node-negative patients that do not require adjuvant chemotherapy. Copyright (C) 2005 S. Karger AG, Basel
Measuring body composition in overweight individuals by dual energy x-ray absorptiometry
BACKGROUND: Dual energy x-ray absorptiometry (DXA) is widely used for body composition measurements in normal-weight and overweight/obese individuals. The limitations of bone densitometers have been frequently addressed. However, the possible errors in assessing body composition in overweight individuals due to incorrect positioning or limitations of DXA to accurately assess both bone mineral density and body composition in obese individuals have not received much attention and are the focus of this report. DISCUSSION: We discuss proper ways of measuring overweight individuals and point to some studies where that might not have been the case. It appears that currently, the most prudent approach to assess body composition of large individuals who cannot fit under the scanning area would be to estimate regional fat, namely the regions of thigh and/or abdomen. Additionally, using two-half body scans, although time consuming, may provide a relatively accurate measurement of total body fat, however, more studies using this technique are needed to validate it. SUMMARY: Researchers using bone densitometers for body composition measurements need to have an understanding of its limitations in overweight individuals and address them appropriately when interpreting their results. Studies on accuracy and precision in measurements of both bone and soft tissue composition in overweight individuals using available densitometers are needed
Measurement of the t(t)over-bar production cross section in the dilepton channel in pp collisions at √s=8 TeV
The top-antitop quark (t (t) over bar) production cross section is measured in proton-proton collisions at root s = 8 TeV with the CMS experiment at the LHC, using a data sample corresponding to an integrated luminosity of 5.3 fb(-1). The measurement is performed by analysing events with a pair of electrons or muons, or one electron and one muon, and at least two jets, one of which is identified as originating from hadronisation of a bottom quark. The measured cross section is 239 +/- 2 (stat.) +/- 11 (syst.) +/- 6 (lum.) pb, for an assumed top-quark mass of 172.5 GeV, in agreement with the prediction of the standard model
Comparative analysis of medicinal plants used in traditional medicine in Italy and Tunisia
<p>Abstract</p> <p>Background</p> <p>Italy and Tunisia (Africa for the Romans), facing each other on the opposite sides of the Mediterranean Sea, have been historically linked since the ancient times. Over the centuries both countries were mutually dominated so the vestiges and traces of a mutual influence are still present. The aim of the present study is to conduct a comparative analysis of the medicinal species present in the respective Floras in order to explore potential analogies and differences in popular phytotherapy that have come out from those reciprocal exchanges having taken place over the centuries</p> <p>Methods</p> <p>The comparative analysis based on the respective floras of both countries takes into consideration the bulk of medicinal species mutually present in Italy and Tunisia, but it focuses on the species growing in areas which are similar in climate. The medicinal uses of these species are considered in accordance with the ethnobotanical literature.</p> <p>Results</p> <p>A list of 153 medicinal species belonging to 60 families, present in both floras and used in traditional medicine, was drawn. A considerable convergence in therapeutic uses of many species emerged from these data.</p> <p>Conclusion</p> <p>This comparative analysis strengthens the firm belief that ethno-botanical findings represent not only an important shared heritage, developed over the centuries, but also a considerable mass of data that should be exploited in order to provide new and useful knowledge.</p
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