High Incidence of Virulence Factors among Clinical Enterococcus faecalis Isolates in Southwestern Iran

Hamid Heidari,Somayeh Hasanpour,Hadi Sedigh Ebrahim-Saraie,Mohammad Motamedifar 대한감염학회 2017 Infection and Chemotherapy Vol.49 No.1

Background: Over the past two decades, enterococci have emerged as an important agent responsible for hospital acquiredinfection. Several virulence factors contribute to the adherence, colonization, evasion of the host immune response, and pathogenicityand severity of the infection. Enterococcus faecalis is the most common and virulent species causing infections in hospitalizedpatients. The aim of the present study was to examine the prevalence of genes encoding virulence factors and antimicrobialresistance patterns of E. faecalis strains isolated from hospitalized patients in Shiraz, south west of Iran. Materials and Methods: A total of 51 E. faecalis isolates from the urine, blood, pleural fluid, peritoneal fluid, eye discharge,endotracheal tube (ETT) and transjugular intrahepatic portosystemic shunt (TIPS) specimens of patients were identified by phenotypicand genotypic methods. Antimicrobial sensitivity tests and detection of virulence factors were performed using standardmethods. Results: The efa and asa1 were the most frequently detected gene (100%) among the isolates, followed by esp (94.1%), ace(90.2%), gelE (80.4%), cylA (64.7%), and hyl (51%). More than half of the isolates (52.9%) were high level gentamicin resistant(HLGR). Vancomycin resistance was observed among 23 (45.1%) isolates. The lowest antimicrobial activity was related to erythromycin(3.9%), tetracycline (5.9%) and ciprofloxacin (9.8%). No isolate was found resistant to fosfomycin and linezolid. Conclusion: Our data indicated a high incidence of virulence factors among E. faecalis strains isolated from clinical samples. Colonization of drug resistant virulent isolates in hospital environment may lead to life threatening infection in hospitalized patients. Therefore, infection control procedures should be performed.

Somatic Complaints Are Significantly Associated with Chronic Uninvestigated Dyspepsia and Its Symptoms: A Large Cross-sectional Population Based Study

( Zahra Heidari ),( Ammar Hassanzadeh Keshteli ),( Awat Feizi ),( Hamid Afshar ),( Payman Adibi ) 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2017 Journal of Neurogastroenterology and Motility (JNM Vol.23 No.1

Background/Aims Somatization may influence persistence and severity of symptoms in gastrointestinal diseases. Some studies suggest that somatization is associated with chronic uninvestigated dyspepsia (CUD); however, the association is unclear. We aimed to determine the association between the profiles of somatic complaints with CUD and its symptoms. Methods In a cross-sectional study conducted on 4763 Iranian adults, somatic complaints were assessed using a comprehensive 31-items questionnaire. Patients with CUD were identified by the Rome III diagnostic criteria. Profiles of somatic complaints were derived from factor analysis. Logistic regression analysis was used to assess the relationship between extracted profiles with CUD and its symptoms. Results CUD, bothersome postprandial fullness, early satiation, and epigastric pain or burning was identified in 723 (15.2%), 384 (8.1%), 302 (6.3%), and 371 (7.8%) of the study population. The frequency of all 31 somatic complaints was significantly higher in patients with CUD compared with controls (P < 0.001), and the most frequent was severe fatigue (45.1%). The profiles of somatic complaints were extracted in 4 domains, including “psychological”, “gastrointestinal”, “neuro-skeletal”, and “pharyngeal-respiratory”. The psychological (OR, 1.49; 95% CI, 1.44-1.54), gastrointestinal (OR, 2.22; 95% CI, 2.09-2.37), neuro-skeletal (OR, 1.52; 95% CI, 1.44- 1.59), and pharyngeal-respiratory (OR, 2.09; 95% CI, 1.94-2.25) profiles were significantly associated with greater odds of CUD. Conclusions CUD and its symptoms are strongly associated with higher levels of somatic complaints and their related extracted profiles. This perhaps explains that why it can be difficult to treat, however further prospective investigations are required to confirm these associations. (J Neurogastroenterol Motil 2017;23:80-91)

Evaluation of Methylobacterium radiotolerance and Sphyngomonas yanoikoaie in Sentinel Lymph Nodes of Breast Cancer Cases

Yazdi, Hamid Reza,Movafagh, Abolfazl,Fallah, Fateme,Shargh, Shohreh Alizadeh,Mansouri, Neda,Pour, Atefeh Heidary,Hashemi, Mehrdad Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.no.sup3

It has been established that different kinds of bacteria agents are involved in various cancers. Although the mechanism of tumorigenesis is not clearly understood, there is evidence for the presence of bacteria within tumors, with at least a progression effect for some bacteria that prepare suitable microenvironments for tumor cell growth. The aim of current study was to evaluate bacterial dysbiosis in sentinel lymph nodes of breast cancer patients. One hundred and twenty three fresh-frozen sentinel lymph nodes and a corresponding number of normal adjacent breast tissue specimens and five normal mastectomy samples were investigated employing RT-PCR. In addition using genus-specific primers were applied. There was a significant differences as presence of Methylobacterium radiotolerance DNA recorded between patients and normal control group (p= 0.0). Based on our research work, further studies into the role of microbes in breast cancer would be of great interest.

Synthesis of dehydrated magnesium borate powders and the effect on the properties of MgO-C refractories

Mahdi Heidari Bagherabadi,Rahim Naghizadeh,Hamid Reza Rezaie,Mohsen Fallah Vostakola 한양대학교 세라믹연구소 2018 Journal of Ceramic Processing Research Vol.19 No.3

For the synthesis of magnesium borate powder, magnesium carbonate and boric acid powders were mixed in ethanol and theninvestigated by differential thermal analysis (DTA) and thermogravimetry (TG). X-ray diffraction (XRD) results of thesamples showed the formation of Mg2B2O5 phase at 500 oC and Mg3B2O6 at 650 oC. The synthesized powder used as anantioxidant additive in magnesia-graphite bodies containing 20% graphite. After curing at 200 oC and firing at 1200 oC and1400 oC for 2 hrs in a coke bed environment, its physical and mechanical properties and also microstructural features wereinvestigated. The results showed that after curing at 250 oC, the addition of magnesium borate led to an increase in coldcrushing strength at about 20%. Comparing the samples with additives and without any additives at 1200 and 1400 oC showedthat the cold crushing strengths were improved about 45%, 35%, respectively. In addition, the results clarified that magnesiumborate (Mg3B2O6) phase led to improve oxidation resistance.

Numerical investigation of cyclic performance of frames equipped with tube-in-tube buckling restrained braces

Shahrokh Maalek,Hamid Heidary-Torkamani,Moharram Dolatshahi Pirooz,Seyed Taghi Omid Naeeini 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.30 No.3

In this research, the behavior of tube-in-tube BRBs (TiTBRBs) has been investigated. In a typical TiTBRB, the yielding core tube is located inside the outer restraining one to dissipate energy through extensive plastic deformation, while the outer restraining tube remains essentially elastic. With the aid of FE analyses, the monotonic and cyclic behavior of the proposed TiTBRBs have been studied as individual brace elements. Subsequently, a detailed finite element model of a representative single span-single story frame equipped with such a TiTBRB has been constructed and both monotonic and cyclic behavior of the proposed TiTBRBs have been explored under the application of the AISC loading protocol at the braced frame level. With the aid of backbone curves derived from the FE analyses, a simplified frame model has been developed and verified through comparison with the results of the detailed FE model. It has been shown that, the simplified model is capable of predicting closely the cyclic behavior of the TiTBRB frame and hence can be used for design purposes. Considering type of connection detail used in a frame, the TiTBRB member which behave satisfactorily at the brace element level under cyclic loading conditions, may suffer global buckling due to the flexural demand exerted from the frame to the brace member at its ends. The proposed TiTBRB suit tubular members of offshore structures and the application of such TiTBRB in a typical offshore platform has been introduced and studied in a single frame level using detailed FE model.

Effect of agitation speed on microencapsulation of healing agent in PMMA shell and study on the mechanical properties of epoxy/PMMA microcapsules

Ramin Jahadi,Hamid Beheshti,Mohammad Heidari-Rarani,Amir H Navarchian 국제구조공학회 2021 Smart Structures and Systems, An International Jou Vol.27 No.6

In this study, the effect of agitation speed as a key process parameter on the morphology and particle size of epoxy-Poly (methyl methacrylate) (PMMA) microcapsules was investigated. Thus, a new interpretation is presented to relate between the microcapsule size to rotational speed so as to predict the particle size at different agitation speeds from the initial capsule size. The PMMA shell capsules containing EC 157 epoxy and hardener as healing materials were fabricated through the internal phase separation method. The process was performed at 600 and 1000 rpm mechanical mixing rates. Scanning electron microscopy (SEM) revealed the formation of spherical microcapsules with smooth surfaces. According to static light scattering (SLS) results, the average diameter size of the epoxy/PMMA capsules at two mixing rates were 7.49 and 5.11 μm for 600 and 1000 rpm, respectively, indicating that the mean size increased as the mixing rates of the process increased. The D₅₀, D₉₀ and mean particle size values were the lowest for hardener/PMMA microcapsules at 1000 rpm. Moreover, the Fourier transform infrared (FTIR) spectroscopy was conducted to describe the chemical structure of epoxy and hardener PMMA capsules. To investigate the reinforcing role of microcapsules, they embedded in EPL-1012 epoxy resin with various amounts of 1 and 2.5 wt.% epoxy/PMMA capsules. The investigation also involved the effect of microcapsules on mechanical behavior as well as the reinforcement of polymer composite material. Experimental results showed that the tensile strength of the self-healing polymer composite slightly increased by 1 wt.% PMMA microcapsules prepared at 1000 rpm and then reduced with an increase in the concentration and mean size diameter of PMMA microcapsules. In addition, a similar trend of Young's modulus was seen for pristine epoxy matrix and microcapsule-loaded epoxy composite.

Experimental study of collapse mode and crashworthiness response of tempered and annealed aluminum tubes under axial compression

Majid Emadi,Hamid Beheshti,Mohammad Heidari-Rarani,Farhad Haji Aboutalebi 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.5

Thin-walled aluminum tubes have been widely used in engineering structures, aerospace and transportation industries due to their excellent properties. In this paper, the effect of tempering and annealing on the crushing behavior of aluminum alloy tubes, in brittle or ductile manner, under quasi-static compression were investigated. The chemical composition, the Brinell hardness number and the tensile stress-strain curves of various types of Al alloys, i.e., Al 2024, Al 7075 and Al 6061 were obtained in both tempered and annealed state. Then, the axial compression tests were performed on the tubes by a universal testing machine at a controlled displacement rate of 5 mm/min. The crushing mode, load-displacement curve, and crashworthiness characteristics were achieved to obtain specifications of mentioned aluminum tubes. Annealing process, apart from changing the deformation mode and material strength, has often reduced energy absorption in the ductile alloy, Al 6061, and increased in brittle alloys, Al 2024-T3, T4 and Al 7075-T651. This process could also be used as a triggering mechanism to decrease the initial peak force. These experimental results give useful information regarding the material behavior of aluminum alloys to be utilized in the design process of crashworthy components.

Gene cloning, bacterial expression, and purification of calreticulin from Anopheles stephensi (AsCRT)

Nahid BORHANI,Mansour HEIDARI,Hamid R. BASSERI 한국곤충학회 2012 Entomological Research Vol.42 No.1

During the invasion of Plasmodium ookinetes to the mosquito midgut epithelium, several proteins or glycoproteins are involved. Recent study has shown that the calreticulin (CRT) of the midgut from Anopheles albimanus can bind to the protein receptor Pvs25 on surface of Plasmodium vivax ookinetes. Thus, in order to get more insight into the potential roles of Anopheles stephensi calreticulin (AsCRT) in the midgut, we amplified and cloned the full-length of calreticulin coding sequence from Anopheles stephensi. The AsCRT consists of 1221 bp nucleic acids with one open reading frame (ORF) encoding 406 amino acids and an apparent molecular weight around 46 KDa. Subsequently, the recombinant calreticulin as Glutathione S-transferase (GST) fusion in pGEX -6p-1 expression vector (GST-AsCRT) was produced in the prokaryotic system under optimum conditions. GST-AsCRT fusion protein has a molecular weight around 73 KDa. The recombinant protein was detected byWestern blotting using a rabbit anti-GST polyclonal antibody. Here, we report via single protein purification procedure using MagneGST beads, 25 mg of the recombinant protein was obtained per liter of bacterial culture. This is the first report describing the heterologous expression of Anopheles stephensi calreticulin in the prokaryotic system. The production of this recombinant protein will now allow us to further investigate AsCRT molecular protein analyses, characterization of physiochemical properties, as well as interaction between calreticulin and plasmodium protein surface.

Effects of Exendin-4 on Male Reproductive Parameters of D-Galactose Induced Aging Mouse Model

Akram Ahangarpour,Ali Akbar Oroojan,Hamid Heidari 대한남성과학회 2014 The World Journal of Men's Health Vol.32 No.3

Purpose: The purpose of this study was to evaluate the role of exendin-4 on reproductive alteration in a D-galactose-induced aging mouse model. Materials and Methods: In this experimental study, 72 male Naval Medical Research Institute mice (20∼25 g) were randomly divided into six groups: control, exendin-4 (1 nmol/kg), exendin-4 (10 nmol/kg), D-galactose (500 mg/kg), D-galactose+ exendin-4 (1 nmol/kg), and D-galactose+exendin-4 (10 nmol/kg). The aging model animals were gavaged with D-galactose for six weeks, and exendin-4 was injected intraperitoneally in the last 10 days. At the end of treatment serum luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone levels were evaluated and the cauda epididymis and testis were removed to analyze the sperm count and testis morphology. Results: The testis weight and volume decreased in the D-galactose group (p<0.01 and p<0.05) respectively. Exendin-4 (1, 10 nmol/kg) increased these parameters in the normal and aging mouse models. Serum LH and FSH levels increased and the sperm count decreased in the D-galactose group (p<0.05). Further, exendin-4 (1 nmol/kg) decreased LH and FSH levels and increased the serum testosterone level and sperm count in both normal and aging animals. Conclusions: D-galactose can induce aging alternations in the male reproductive system such as decreased sperm count and increased serum LH and FSH levels through reactive oxygen species over production and reduced antioxidant enzyme activity. Further, co-administration of exendin-4 reduced reproductive complications of D-galactose in an aging mouse model.

Effects of Hydro-Alcoholic Extract of Rhus coriaria (Sumac) Seeds on Reproductive Complications of Nicotinamide-Streptozotocin Induced Type-2 Diabetes in Male Mice

Akram Ahangarpour,Ali Akbar Oroojan,Hamid Heidari,Ehsan Ghaedi,Mohammad Reza Rashidi Nooshabadi 대한남성과학회 2014 The World Journal of Men's Health Vol.32 No.3

Purpose: The purpose of this study was to investigate the effects of the hydro-alcoholic extract of Rhus coriaria seeds on the reproductive system of nicotinamide-streptozotocin-induced type-2 diabetic mice. Materials and Methods: In this experimental study, 56 male Naval Medical Research Institute mice were randomly divided into seven groups (n=8): control; diabetic mice; diabetic mice administered glibenclamide (0.25 mg/kg); diabetic mice who received the hydro-alcoholic extract of R. coriaria seeds (200 and 400 mg/kg groups); and normal mice who received this extract (200 and 400 mg/kg groups). Diabetes was induced by intraperitoneal administration of streptozotocin (65 mg/kg) 15 minutes after an injection of nicotinamide (120 mg/kg). Then, glibenclamide and the above mentioned extract were administered orally for 28 consecutive days. Twenty-four hours after the last treatment, serum samples, the testes, and the cauda epididymis were removed immediately for hormonal, testis morphology, and sperm parameter assessments. Results: Body and testicular weight, sperm count and viability, and serum luteinizing hormone, follicle-stimulating hormone and testosterone levels were significantly lower in the diabetic mice (p<0.05). The diabetic mice treated with 400 mg/kg of the hydro-alcoholic extract of R. coriaria seeds recovered from these reductions (p<0.05). Further, glibenclamide alleviated hormonal and sperm count depletion in diabetes-induced mice (p<0.05). Conclusions: The present results indicated that the hydro-alcoholic extract of R. coriaria seeds has anti-infertility effects in diabetic males.