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11.
High rate of A2142G point mutation associated with clarithromycin resistance among Iranian Helicobacter pylori clinical isolates 下载免费PDF全文
Reza Khashei Mahintaj Dara Abdollah Bazargani Kamran Bagheri Lankarani Alireza Taghavi Maryam Moeini Behzad Dehghani Maryam Sohrabi 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(9):787-793
This study aimed to investigate the clarithromycin resistance and its associated molecular mechanisms among Helicobacter pylori isolates from dyspeptic patients in Shiraz, Iran. From January to May 2014, 100 H. pylori strains were isolated from patients with gastroduodenal disorders. The resistance to clarithromycin was quantitatively evaluated, using Epsilometer (E‐test) method. Polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) was performed on all the isolates to detect A2143G and A2142G mutations in 23S rRNA gene. The H. pylori isolation rate was found to be 31.4%. E‐test showed that 20% of isolates were resistant to clarithromycin (MIC ≥ 1 mg/L). MIC of clarithromycin ranged between 0.016 and 24 mg/L. Findings of PCR‐RFLP showed that the A2142G was the most (90%) frequently point mutation, followed by the A2143G (10%). No statistically significant difference was found between H. pylori clarithromycin resistance point mutations and patients’ gender or age. To the best of our knowledge, this is the first report of high frequency of A2142G point mutation in Iran and probably in other regions of the world. Considering the increasing trend of H. pylori resistance to clarithromycin due to these mutations, it is crucial to investigate the new therapeutic approaches against H. pylori infection. 相似文献
12.
13.
The association between obesity and migraine in a population of Iranian adults: a case-control study
Ali Miri Morteza Nasiri Sahar Zonoori Fatemeh Yarahmad Arasb Dabbagh-Moghadam Gholamreza Askari Omid Sadeghi Masoumeh Asadi 《Diabetes & Metabolic Syndrome: Clinical Research & Reviews》2018,12(5):733-736
Aim
To assess the association between obesity and risk of migraine with aura and features of migraine attacks among a population of Iranian adults.Methods
In this case-control study, 102 confirmed cases of migraine with aura were matched based on age and gender with 102 healthy subjects. Data on demographic characteristics and anthropometric measurements were collected from all cases and controls by the same methods. Overweight and obesity were considered as body mass index ≥25–30?kg/m2 and?≥?30?kg/m2, respectively. Features of migraine attacks including frequency, duration and headache daily result were determined for patients based on international headache society criteria.Results
Mean age of subjects was 34.5?±?7.4 years and 77.9% of them were female. Compared with subjects with normal body mass index, those with obesity had greater odds for having migraine with aura (OR: 3.06, 95% CI: 1.11–8.43). Such finding was also seen even after adjusting for confounding variables; in a way that subjects with obesity were 2.92 times more likely for having migraine with aura compared with those with normal weight (OR: 2.92, 95% CI: 1.03-8.33). Among migraine with aura patients, we found that those with obesity had higher headache daily result compared with subjects with normal weight. However, obesity was not associated with frequency and duration of migraine attacks.Conclusions
We found that obesity was positively associated with risk of migraine with aura. In addition, subjects with obesity had higher headache daily result compared with those with normal weight. 相似文献14.
Liver transplantation as a definitive treatment for familial hypercholesterolemia: A series of 36 cases 下载免费PDF全文
Mohsenreza Mansoorian Kourosh Kazemi Saman Nikeghbalian Alireza Shamsaeefar Maral Mokhtari Seyed Mohsen Dehghani Ali Bahador Heshmatollah Salahi Hamid Amoozgar Seyed Ali Malek Hosseini 《Pediatric transplantation》2015,19(6):605-611
FH is a genetic disorder characterized by an increase in serum LDL and total cholesterol values. The afflicted patients are at increased risk of premature atherosclerosis and myocardial infarction. Different treatment modalities are present, including pharmacological agents and surgical procedures. The most effective method of therapy in refractive cases is liver transplantation. Herein, we report our experience on 36 cases of patients with FH undergoing liver transplantation in our center, the main referral center of liver transplantation in Iran. The clinical findings, hospital courses, post‐operative complications, and patient follow‐up are also described. 相似文献
15.
Mahsa Lotfollahi Masoumeh Gity Jing Yong Ye A. Mahlooji Far 《Journal of Medical Ultrasonics》2018,45(2):205-212
Purpose
Ultrasound imaging is an effective approach for diagnosing breast cancer, but it is highly operator-dependent. Recent advances in computer-aided diagnosis have suggested that it can assist physicians in diagnosis. Definition of the region of interest before computer analysis is still needed. Since manual outlining of the tumor contour is tedious and time-consuming for a physician, developing an automatic segmentation method is important for clinical application.Methods
The present paper represents a novel method to segment breast ultrasound images. It utilizes a combination of region-based active contour and neutrosophic theory to overcome the natural properties of ultrasound images including speckle noise and tissue-related textures. First, due to inherent speckle noise and low contrast of these images, we have utilized a non-local means filter and fuzzy logic method for denoising and image enhancement, respectively. This paper presents an improved weighted region-scalable active contour to segment breast ultrasound images using a new feature derived from neutrosophic theory.Results
This method has been applied to 36 breast ultrasound images. It generates true-positive and false-positive results, and similarity of 95%, 6%, and 90%, respectively.Conclusion
The purposed method indicates clear advantages over other conventional methods of active contour segmentation, i.e., region-scalable fitting energy and weighted region-scalable fitting energy.16.
17.
Hassan Niknejad Ghasem Yazdanpanah Masoumeh Mirmasoumi Hassan Abolghasemi Habibollah Peirovi Abolhassan Ahmadiani 《Medical hypotheses》2013
Amniotic membrane (AM), the innermost layer of the fetal membrane, is considered as a suitable candidate for cancer therapy. In order to develop the AM as a new cancer therapeutic approach, it is essential to understand the molecular mechanism of the AM anti-cancer properties. Previous studies demonstrated that anti-proliferative effects of the AM on tumor cells were associated with induction of cell cycle arrest. Moreover, it has been shown that unknown substances in the AM induce apoptosis in cancer cells and inhibit angiogenesis in tumors. In contrast to the effects of the AM, heat shock proteins (HSPs), in particular HSP90, play a crucial role in development of tumorgenesis. HSP90 inhibits apoptosis in cancer cells and enhances angiogenesis and cell cycle progression. Based on the opposite effects of the amniotic membrane ingredients and HSP90, we hypothesized here that possible mechanism of the AM anti-cancer effects is through inhibition of HSP90. 相似文献
18.
Masoumeh Bagheri 《International reviews of immunology》2013,32(5):217-228
Toll-like receptors (TLRs) are known for their essential roles in promotion of innate immunity and induction of adaptive immunity through recognition of pathogen-associated molecular patterns (PAMPs) or danger associated molecular patterns (DAMPs). TLR genes are excellent models for the study of the selective pressure enforced by microorganisms on the host genome. Phylogenetic analyses have shown that interactions between pathogens and immune systems have changed during evolution. Selective pressure for maintenance of specific pathogen recognition has led to evolution of TLRs under both positive and purifying selection. However, intracellular and cell-surface TLRs have been affected differently due to their variation in conservational constraints. In this review, we summarize some of the main studies on the influence of selection on shaping the evolution of several TLR gene families in different terrestrial vertebrate species. We also describe the effect of evolution on the function of different TLRs and their specific conservations in these species and show similarities and differences in evolutionary patterns of TLR orthologs among species as well as among TLR gene families. 相似文献
19.
Masoumeh Fallahian Neil J. Sebire Philip M. Savage Michael J. Seckl Rosemary A. Fisher 《Human mutation》2013,34(2):301-308
Digynic triploidy is classically associated with a severely growth restricted fetus and a small nonmolar placenta. However, in genotyping hydatidiform moles as part of clinical practice, we identified two digynic triploid conceptions presenting with histopathological features of classical complete hydatidiform mole (CHM). Both cases occurred in women with a history of previous molar pregnancies and no normal pregnancies. Pathological review and genotyping of other molar pregnancies in these cases showed them to be typical CHM with negative p57KIP2 immunostaining of the cytotrophoblast cells and villous stroma and to be diploid but biparental, confirming a diagnosis of familial recurrent hydatidiform mole (FRHM). Mutation screening of NLRP7 had identified a homozygous duplication, leading to a truncated protein, in case 1 whereas mutation screening of KHDC3L (C6orf221) in case 2 showed both the proband and her sister to be compound heterozygotes for mutations in KHDC3L. The observation of a single digynic, triploid conception presenting as a CHM in women with FRHM, where other pregnancies are diploid and biparental, supports the hypothesis that the role of both NLRP7 and KHDC3L in pregnancy is in setting and/or maintaining the maternal imprint. Clinically, a diagnosis of FRHM should be considered in women with genetically unusual conceptions that are phenotypically CHM. 相似文献
20.
Belal Hassanzadeh Abolghasem Nabipour Morteza Behnam Rassouli Hesam Dehghani 《Anatomical science international / Japanese Association of Anatomists》2013,88(3):134-140
The majority of investigations on the testis, as the main organ of male reproductive system, have been performed in mammalian species, with few studies on bird species. Thus, the structure of the ostrich testis remains largely unknown. The aim of this study was to investigate the microanatomical characteristics of the testis in five juvenile ostriches. A stereological study was performed according to the Delesse principle. The mean volume fraction of the seminiferous tubules was 0.569, and the mean volume of the seminiferous tubules in an average testis was 1.04 cm3. The Paraffin-embedded sections were stained with hematoxylin and eosin, Masson’s trichrome, Alcian blue, and periodic acid–Schiff stains. Histological studies revealed that the spermatogonial stem cells and Sertoli cells were localized inside the seminiferous tubules, close to the basement membrane. Inside the tubules a few meiotic cells up to the spermatozoa stage were located in a centripetal manner. Outside the tubules, one to three layers of euchromatic peritubular myoid cells were present, surrounded by loose interstitial connective tissue. A thick tunica albuginea contained many myoid cells and some rete ducts, with the latter extending from the hilus to the free surface of the testis. Straight seminiferous tubules were distributed in the lateral surfaces and hilar portions of the capsule but were rare in the free surface. These capsular rete ducts may participate in testicular fluid transit from the distal tubules through the capsule. 相似文献