Strengthening the mechanical characteristics and cathodic delamination resistance of fiber-reinforced polymer through chemical surface modification of glass fibers.

This work aims to scrutinize the effect of the silanization of glass fibers (GF) on the mechanical properties and cathodic disbonding resistance of an epoxy composite coating. Successful silanization was approved based on different characterization techniques, including Fourier transform infrared spectra, field emission-scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy, and thermogravimetric analysis. Tensile strength measurement exhibited a significant effect of silanization on the mechanical performance of the fiber-reinforced polymer (FRP). FE-SEM cross-sectional images illustrated improved interfacial bonding between the epoxy matrix and GF upon silanization. Pull-off measurements revealed improved wet adhesion strength of the FRP to the mild steel surface after exposure to the salt spray chamber when the GF were silanized. In addition, silanization revealed enhanced resistance to cathodic delamination (CD). Electrochemical impedance spectroscopy and electrochemical noise assessments proved silanization's significant influence on the FRP's CD resistance.

Detection of genomic mutations in katG and rpoB genes among multidrug-resistant Mycobacterium tuberculosis isolates from Tehran, Iran.

Multidrug-resistant (MDR) Mycobacterium tuberculosis strains, defined as resistant to at least isoniazid and rifampin, have emerged as a major worldwide health threat. Spontaneous point mutations in various genes of M. tuberculosis cause resistance to isoniazid, with the most frequent gene target being katG; and resistance to rifampin is usually due to mutation in the rpoB gene. The current study was aimed to detect the point mutations in the katG and rpoB regions related to isoniazid and rifampin resistance. A total of 203 respiratory specimens were collected from patients suspected of having tuberculosis respiratory infections referred to hospitals of Tehran, Iran, during 2018-2019. The isolation and identification of M. tuberculosis isolates were performed according to the WHO protocol. Drug susceptibility testing was carried out by proportional method. PCR analysis and sequencing were used to detect mutations in the selected katG and rpoB regions. Forty-four M. tuberculosis strains were isolated, of which 12 (27.3%) and 10 (22.7%) were resistant to isoniazid and rifampin, respectively. Ten isolates were resistant to both isoniazid and rifampin and were considered as MDR isolates. Of the ten MDR isolates, six (60%) carried mutations in both rpoB and katG. The most common mutations among isoniazid- and rifampin-resistant isolates were in codon 315 of the katG gene (70%) and codon 441 of the rpoB gene (50%), respectively. The results of this study indicated that MDR-TB continues to be a serious public health problem in Iran.

Inductive Materials for Regenerative Engineering.

Regenerative engineering has pioneered several novel biomaterials to treat critical-sized bone injuries. However, despite significant improvement in synthetic materials research, some limitations still exist. The constraints correlated with the current grafting methods signify a treatment paradigm shift to osteoinductive regenerative engineering approaches. Because of their intrinsic potential, inductive biomaterials may represent alternative approaches to treating critical bone injuries. Osteoinductive scaffolds stimulate stem cell differentiation into the osteoblastic lineage, enhancing bone regeneration. Inductive biomaterials comprise polymers, calcium phosphate ceramics, metals, and graphene family materials. This review will assess the cellular behavior toward properties of inductive materials.

Decreased recurrence of symptoms in oral lichen planus with intralesional injection of hyaluronic acid and triamcinolone.

Oral lichen planus (OLP) is a chronic non-infectious, inflammatory, immunological disease. In contrast to skin lesions, which are often self-limiting, oral lesions rarely heal on their own and can be resistant to local and systemic treatments. In this clinical trial, hyaluronic acid (HA) was mixed with triamcinolone for intralesional injection to reduce side effects in the treatment of OLP. This randomized clinical trial with a split-mouth design was performed on 28 patients with OLP. The mouth was divided randomly into two sides: a test side, which received HA combined with triamcinolone, and a control side, which received triamcinolone alone. The rate of symptom recurrence was 74.1% on the control side and 11.1% on the test side (significant difference, P<0.01). Pain scores did not differ between the two groups when assessed after 2 weeks. The group treated with a combination of HA and triamcinolone experienced a significantly better resolution of lesions and symptoms. Considering the role of HA in tissue healing and in regulating inflammatory responses, as well as its antioxidant and hydration properties, it appears that HA could be effective in improving of OLP and decreasing the rate of symptom recurrence.

Modelling Tumor-induced Angiogenesis: Combination of Stochastic Sprout Spacing and Sprout Progression.

BACKGROUND: Angiogenesis initiated by cancerous cells is the process by which new blood vessels are formed to enhance oxygenation and growth of tumor. OBJECTIVE: In this paper, we present a new multiscale mathematical model for the formation of a vascular network in tumor angiogenesis process. METHODS: Our model couples an improved sprout spacing model as a stochastic mathematical model of sprouting along an existing parent blood vessel, with a mathematical model of sprout progression in the extracellular matrix (ECM) in response to some tumor angiogenic factors (TAFs). We perform simulations of the siting of capillary sprouts on an existing blood vessel using finite difference approximation of the dynamic equations of some angiogenesis activators and inhibitors. Angiogenesis activators are chemicals secreted by hypoxic tumor cells for initiating angiogenesis, and inhibitors of the angiogenesis are chemicals that are produced around every new sprout during tumor angiogenesis to inhibit the formation of further sprouts as a feedback of sprouting in angiogenesis. Moreover, for modelling sprout progression in ECM, we use three equations for the motility of endothelial cells at the tip of the activated sprouts, the consumption of TAF and the production and uptake of Fibronectin by endothelial cells. RESULTS: Coupling these two basic models not only does provide a better time estimation of angiogenesis process, but also it is more compatible with reality. CONCLUSION: This model can be used to provide basic information for angiogenesis in the related studies. Related simulations can estimate the position and number of sprouts along parent blood vessel during the initial steps of angiogenesis and models the process of sprout progression in ECM until they vascularize a tumor.

Comparative evaluation of low-level laser and CO2 laser in treatment of patients with oral lichen planus.

A comparative evaluation of low-level laser and CO(2) laser therapies was performed, for the treatment of oral lichen planus (OLP). In a randomized open clinical trial, 28 patients with 57 lesions were randomly assigned to two groups. One group received CO(2) laser therapy, the other received low-level laser therapy (LLLT) for 5 sessions every other day. Participants were examined before the treatment, after 2 weeks, and at 1, 2 and 3 months, to assess the changes in sign and symptom scores. Improvements in size of lesions, in pain and clinical response scores were achieved in both groups. After 3 months, clinical response showed 100% and 85% partial to complete improvement in LLLT and CO(2) laser surgery, respectively. This demonstrates a quick and pronounced beneficial effect in controlling symptoms related to OLP. Both methods may be effective in the treatment of OLP, and can be used as alternative therapy alongside standard treatment modalities. The present study showed that LLLT displayed better results than CO(2) laser therapy as alternative or additional therapy, but further investigations in comparison with standard treatment modalities with a prolonged follow-up period will be necessary to confirm the efficacy of laser therapy in the treatment of OLP.

Serum and saliva magnesium in postmenopausal women with xerostomia.

OBJECTIVES: The aim of this study was to investigate serum, stimulated and unstimulated salivary magnesium in postmenopausal women with xerostomia. MATERIALS: A case-control study was carried out on 60 selected postmenopausal women aged 41-77 years with or without xerostomia (30 as cases with xerostomia and 30 as controls without xerostomia), conducted at the Clinic of Oral Medicine, Tehran University of Medical Sciences. Unstimulated and paraffin-stimulated saliva samples were obtained by expectoration. Magnesium concentration was determined by the spectrophotometer method. Statistical analysis was carried out using Student's t-test. RESULTS: The mean serum concentration, but not stimulated and unstimulated whole saliva magnesium concentrations, was significantly higher in the cases than in the controls. CONCLUSION: Serum magnesium level appears to be associated with xerostomia in menopause.

Relationship of unstimulated saliva cortisol level with severity of oral dryness feeling in menopausal women.

BACKGROUND: Menopause may be associated with some adverse changes, such as oral dryness (OD) feeling. The exact mechanisms that mediate sensation of OD in menopausal women have not been firmly established. The purpose of this study was to assess the relationship of unstimulated whole saliva cortisol level with severity of OD feeling in menopausal women. METHODS: A case control study was carried out on 70 selected menopausal women with/without OD feeling, conducted at the Clinic of Oral Medicine, Tehran University of Medical Sciences, Iran. The xerostomia inventory (XI) score was used as an index of OD feeling severity. Unstimulated whole saliva cortisol concentration was measured by ELISA. Statistical analysis of student's t-test and Spearman correlation was used. RESULTS: The mean cortisol concentration of saliva was significantly higher in women with OD feeling than the control. There was significant positive correlation between the XI score and the concentration of unstimulated whole saliva cortisol (r = 0.559, p = 0.025). CONCLUSIONS: Unstimulated whole saliva cortisol is higher in menopausal women with OD feeling than in controls and this correlates with the severity of OD.

Seroprevalence of Toxoplasma gondii Infection in Dogs in Tehran, Iran.

BACKGROUND: Toxoplasma gondii infects a wide range of animals; felines are definitive hosts and other animals including the dogs are intermediate hosts. The aim of this study was to determine the seroprevalence of T. gondii infection in dogs in Tehran, capital of Iran and to investigate possible associated risk factors. METHODS: Three hundreds ninety six serum samples were collected during 2007-8 from the dogs. Collected samples were tested using an indirect fluorescent antibody test (IFAT) in dilutions of 1:16 and more. All procedures were carried out in Shahrekord University, Iran. All the data were analyzed using SPSS software, qui square test with confidence interval of 0.95. RESULTS: From evaluated samples, 89 (22.47%) were positive in titers of at least 1:16. further evaluations in other dilutions showed positive results in dilutions of maximum 1:16, 1:32, 1:64, 1:128 and 1:256 in 38, 29, 15, 2 and 5 dogs respectively. Investigation of the role of risk factors showed no sex predisposition while infection rate was significantly higher in dogs older than one year old. Living places were of significant importance; infection rate was significantly higher in stray or guard dogs in compare with household dogs (P<0.05). CONCLUSION: Relatively high seroprevalence of T. gondii infection in dogs in Tehran shows high environmental contamination. It is recommended that the dogs with suspected clinical signs be tested for T. gondii infection.

Antimicrobial activity of different Lactobacillus species against multi- drug resistant clinical isolates of Pseudomonas aeruginosa.

BACKGROUND: Lactobacilli are the well known friendly bacteria for their probiotic activities against pathogens. The inhibitory activity of different strains of lactobacilli either obtained as commercial products or isolated from human feces was investigated against the clinical isolates of Pseudomonas aeruginosa. The isolates were selected as the most resistant strains when challenged with anti-pseudomonal antibiotics already in clinical practice. MATERIALS AND METHODS: Both the plate spot test as well as the agar cup method were used for screening of Lactobacillus strains against Pseudomonas aeruginosa. RESULTS: A Lactobacillus acidophilus strain isolated from feces of an Iranian child showed a strong anti-pseudomonal activity (90 percent after 72h incubation) against the multi-drug resistant clinical isolates while a Lactobacillus reuteri strain isolated from a commercial oral product resulted in relatively weak response and a Lactobacillus acidophilus strain isolated from a commercial vaginal product did not show any inhibitory activity. In a kinetic study the lactobacillus sensitive Pseudomonas aeruginosa showed a significant bacteriostatic activity in vitro in the presence of lactobacillus supernatants. CONCLUSION: Some lactobacilli exhibit significant inhibitory activity against the multidrug resistant clinical isolates of Pseudomonas aeruginosa.

Development of an indirect ELISA test using an affinity purified surface antigen (P38) for sero-diagnosis of canine Neospora caninum infection.

Neospora caninum is an intracellular protozoan that infects domestic and wild canids, as well as many warm blooded animals as shown by the isolation of viable parasites and the detection of parasite DNA in naturally infected hosts. N. caninum is described as a cause of neuromuscular disease and death in dogs. The dog is also known as a definitive host, shedding oocysts involved in the transmission of the infection to intermediate hosts. This study was conducted to develop an indirect ELISA test using an affinity purified 38 kDa N. caninum surface antigen (P38) for the sensitive and specific diagnosis of this infection in dog populations. To define a suitable cut-off, serum samples from 233 dogs were analyzed using an N. caninum-specific indirect fluorescent antibody test. All of these serum samples were subjected to the newly designed P38-ELISA. The Two-graph Receiver Operating Characteristics (TG-ROC) of the serum ELISA was determined to examine the performance of the test. TG-ROC analysis showed an area under curve (AUC) of 0.996 that indicates the test results being highly accurate. Optimal sensitivity and specificity (100% and 97.9%, respectively) were determined for SI(n) cut-off point of 0.23. To examine possible cross-reactions with other parasites affecting dogs, sera of dogs positive for antibodies against Toxoplasma gondii (n=17) and Leishmania infantum (n=11) infections were tested. These revealed negative results when tested in the new ELISA.

Effect of beta carotene on lipid peroxidation and antioxidant status following renal ischemia/reperfusion injury in rat.

BACKGROUND: The production of free radicals and reactive oxygen species are important factors contributing to ischemia/reperfusion injury. Thus scavenging of the excess free radicals can be an important therapeutic approach. Beta carotene, a carotenoid pigment has a potent antioxidant property. The present study examined the effect of beta carotene administration on the level of renal content of antioxidants and lipid peroxidation following ischemia/reperfusion injury in the rat kidney. METHODS: Male adult Wistar rats (250-300 g) were exposed to 45 min of renal ischemia followed by 4 h of reperfusion. Beta carotene (10, 30 and 100 mg kg(-1)) or vehicle was administered for 5 days prior to ischemia. Renal content of antioxidants and the level of lipid peroxidation were measured after the reperfusion period. RESULTS: Our results showed that ischemia/reperfusion injury increased lipid peroxidation (p < 0.001) and decreased antioxidant (p < 0.001) in renal tissue. Pre-administration of beta carotene could attenuate these alterations (p < 0.05-p < 0.001), although not at all doses. Since beta carotene administration improved renal lipid peroxidation and antioxidants, it seems that beta carotene protects renal tissue against ischemia/reperfusion-induced oxidative damage.

Hepatitis B virus infection in dentistry: a forgotten topic.

More than two billion people have been infected with hepatitis B virus (HBV). Globally, 350-400 million suffer from chronic HBV infection. It is postulated that dentists and dental staff are infected and transmit the virus to their patients more than any other occupation. The aim of this article is to review the HBV incidence in dental society, the points of view of dentists and their patients regarding transmission of the virus during dental procedures, the occurrence of HBV outbreaks in dental clinics and the importance of methods of preventing HBV infection in dentistry.

Protective effect of beta carotene pretreatment on renal ischemia/reperfusion injury in rat.

Renal ischemia/reperfusion injury is a major cause of acute renal failure. The production of free radicals and reactive oxygen species are important factors contributing to ischemia/reperfusion injury. Thus, scavenging of the excess free radicals can be an important therapeutic approach. The present study examined the protective effect of beta carotene against renal ischemia/reperfusion injury in rat. Male adult Wistar rats (250-300 g) were exposed to 45 min of renal ischemia followed by 4 h of reperfusion. Beta carotene (10, 30 and 100 mg kg(-1)) or vehicle was administered for 5 days prior to ischemia. Renal function was assessed by plasma and urinary analysis. Present results showed that ischemia/reperfusion injury increased (p < 0.05-p < 0.001) serum urea and creatinine levels, as well as urinary excretion of protein and calcium and fractional excretion of sodium, while decreased glomerular filtration rate and potassium excretion. However, alterations in these biochemical indices due to ischemia/reperfusion injury were attenuated by beta carotene pretreatment (p < 0.05-p < 0.001), although not by all doses. Since, beta carotene administration improved renal function, it seems that beta carotene protects renal tissue against ischemia/reperfusion-induced oxidative damage.

Increased salivary lipid peroxidation in human subjects with oral lichen planus.

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory mucosal disease of unknown aetiology. Recently, increased oxidative stress has been implicated in the pathogenesis of various diseases. The aim of this study was to evaluate the total antioxidant capacity (TAC) and lipid peroxidation level, in the saliva of patients with OLP. METHOD: Thirty patients with OLP (15 men, 15 women; mean age 44.0, SD +/- 11.4 years) and 30 control subjects (16 men, 14 women; aged 23-67 years), matched for age and gender, were enrolled in this case and control study. This study was conducted at the Clinic of Oral Medicine of Tehran University of Medical Sciences in 2007. The unstimulated whole saliva malondialdehyde (MDA), as an indicator of lipid peroxidation and TAC levels were assayed by thiobarbituric acid and ferric reducing antioxidant potential (FRAP), respectively, in both groups. RESULTS: Mean levels of saliva MDA, but not TAC, in patients with OLP was significantly higher than those of the control group. CONCLUSION: We conclude that OLP patients have more cellular lipid peroxidation than healthy subjects.

Development of an indirect ELISA test using a purified tachyzoite surface antigen SAG1 for sero-diagnosis of canine Toxoplasma gondii infection.

The aim of this study was to use affinity purified 30 kDa Toxoplasma gondii surface antigen (SAG1) in an indirect ELISA and to compare it with an existing indirect fluorescent antibody test (IFAT). 245 serum samples were collected from dogs from three adjacent Iranian provinces. IFAT examination revealed positive results in 73 dogs, with titers ranging from 1:16 to 1:1024. A suitable ELISA cut-off was determined by ROC analysis in comparison with IFAT. Results showed a relative sensitivity and specificity of 94.52% and 93.60%, respectively, for a cut-off value of 0.790 in the ELISA. No cross-reactivity was detected between antibodies against T. gondii and a closely related protozoan parasite, Neospora caninum, using this newly developed ELISA test.

Spontaneous manifestation of polycystic kidney disease following separation anxiety in a Persian cat.

A 4-year-old female Persian cat was referred with the history of separation from the owner. There was no clinical sign and everything had been reported as normal during the veterinary checkup just before separation and traveling. The history and clinical signs were fit to separation anxiety when the cat referred to us. Ten days after the diagnosis and starting of the treatment for separation anxiety, the cat was referred again with the clinical signs of chronic renal failure. Further assessments showed an inherited polycystic kidney disease. Spontaneous manifestation of polycystic kidney disease after separation anxiety indicate that this phenomenon may cause the chronic process of polycystic kidney disease to promote.

Lymphoma in Syrian hamster.

This study describes clinical and pathologic findings in a naturally occurring lymphoma in a Syrian hamster. Lymphoma; the most common tumor of hamster is viral induced tumor with veterinary importance. Clinical signs include emaciation, weakness, lethargy, diarrhea and some rectal bleeding. The present study describes clinical and pathologic findings of lymphoma in Syrian hamster. The disease is naturally occurred.

Drug-related hospital admissions in a generic pharmaceutical system.

1. Generically based pharmaceutical systems exist in a few countries of the world, such as Iran. Most developed countries have free market pharmaceutical systems. Drug-related problems (DRP) have been reported mostly in the Western world but few data are available for generic systems. In this study, we tried to measure the prevalence of drug-related problems leading to hospital admissions in Isfahan, Iran. 2. One thousand consecutive hospital admissions in three major teaching hospitals were studied for a period of 6 months for the presence of DRP as a cause of hospital admissions. Two subcategories of DRP were considered: (i) drug therapy failure; and (ii) adverse drug reactions. Preventability and outcome measures were also assessed. Medications responsible for DRP were classified according to the Anatomic Therapeutic Chemical (ATC) classification of the World Health Organization. 3. Of the 1000 admissions studied, 115 (11.5%) were owing to DRP, 81% as a result of drug therapy failure and 19% as adverse drug reactions. A total of 106 out of the 115 DRP cases (92%) were either preventable or probably preventable, most of which had to do with either prescriber or patient error. An overview of DRP showed that 58.3% resulted in complete recovery, 33.9% in relative recovery and 7.8% in death. Close to 1% of hospital admissions resulted in DRP-related deaths. 4. The overall prevalence of hospital admissions caused by DRP is similar to that in free market pharmaceutical systems. The high preventability rate of these problems should alert clinicians and policy makers to design strategies to curtail this. Also, reasons for differences in subtypes of DRP between the results of this study and those of the literature from free market systems needs to be investigated further.