Vol 4 No 4 (2012)

Articles

  • XML | views: 310 | pages: 164?
  • XML | PDF | downloads: 329 | views: 300 | pages: 165-170

    Background and Objectives: Resistance in Mycobacterium tuberculosis is caused by mutations in genes encoding drug targets. Investigators have already demonstrated the existence of mutations in codons 88 to 94 in the gyrA gene and also in codons 1400, 1401, and 1483 of rrs gene among extensively and extremely drug resistant tuberculosis (XDR & XXDR-TB) strains. The aim of this study was to identify the XDR and XXDR-TB stains based on their mutational   analysis.
    Materials and Methods: Susceptibility testing against first and second–line anti-tuberculosis drugs was performed by the proportional method. Based on susceptibility results, samples were later analyzed, using PCR-SSCP and PCR-RFLP for detection of mutation in gyrA and rrs genes.
    Results: Overall, using proportional method, sixty-three strains (64.9%) were identified as MDR, 8(8.2%) as non-MDR and 26 strains (26.8%) were susceptible. Thirty-one cases (31.9%) were amikacin-resistant and 18 (18.5%) samples were ciprofloxacin-resistant.  Using PCR-SSCP and PCR-RFLP, we identified 6(6.2%) and 7(7.2%) resistant strains, respectively. Discrepancy in strains was cross-checked by sequencing. The results showed no mutation in 66.6% and 77.4% of CIP and AMK- resistant strains.
    Conclusion: Rapid detection of drug-resistant Mycobacterium tuberculosis using molecular techniques could be effective in determining therapeutic regimen and preventing the spread of XDR and MDR TB in the community. We should still keep in mind that a high number of resistant strains may have no mutation in proposed candidate genes.

  • XML | PDF | downloads: 760 | views: 951 | pages: 171-176

    Background and Objectives: Essential oils are volatile compounds that have been used since Middle Ages as antimicrobial, anti-inflammatory, sedative, local anesthetic and food flavoring agents.In the current study, essential oils of Pelargonium graveolens L’Her and Vitex agnus-castus L. were analyzed for their antibacterial activities.
    Materials and Methods: The chemical compositions of essential oils were characterized by GC-MS. Disc diffusion method was used to study antimicrobial activity.
    Results and Conclusion: Inhibition zones showed that the essential oils of the two plants were active against all of the studied bacteria (except Listeria monocytogenes). The susceptibility of the strains changed with the dilution of essential oils in DMSO. The pure essential oils showed the most extensive inhibition zones and they were very effective antimicrobial compounds compared to chloramphenicol and amoxicillin. The most susceptible strain against these two essential oils was Staphylococcus aureus. It seems that β-citronellol is a prominent part of P. graveolens volatile oil and caryophyllene oxide is a famous and important part of V. agnus-castus volatile oil and their probable synergistic effect with other constituents are responsible for the antibacterial effects of these oils. However further studies must be performed to confirm the safety of these oils for use as antimicrobial agents and natural preservatives in different products.

  • XML | PDF | downloads: 192 | views: 230 | pages: 177-179?

    Background and Objectives: Cross Infections (CIs) are considered as a major public health problem worldwide. They cause delay in recovery, increased mortality and morbidity. The purpose of this study is to report the incidence of CIs in our teaching hospital during a 23-month period.
    Materials and Methods: In this descriptive cross-sectional study, 76766 patients from 2009 to 2011 admitted to 17 wards of Imam Reza Hospital in Mashhad were studied for CIs. Patients’ age, sex, site of infection, ward of hospitalization and type of microbial infections were collected and analyzed by SPSS 16.0.
    Conclusion: Results of the present study showed that the incidence of CIs was low (i.e. < 1%) in our hospital and Acinetobacter (25.8%, n = 176) was the most frequent pathogen.

  • XML | PDF | downloads: 201 | views: 264 | pages: 180-186

    Background and Objectives: Ensiling is a conservation method for forage crops. It is based on the fact that anaerobe lactic acid bacteria (LAB) convert water-soluble carbohydrates into organic acids. Therefore, pH decreases and the forage is preserved. The aim of this study was to isolate special kinds of lactic acid bacteria from silage and to study the effect of bacteria, inulin and enzymes as silage additives on the fermentation and aerobic stability of the silage.
    Materials and Methods: The heterofermentative LAB were isolated from corn silages in Broujerd, Iran and biochemically characterized. Acid tolerance was studied by exposure to acidic PBS and growth in bile salt was measured by the spectrophotometric method.
    Results: The results of molecular analysis using 16SrDNA sequences showed that the isolates belonged to Lactobacillus and Enterococcus genera. To enhance stability in acidic environment and against bile salts, microencapsulation with Alginate and Chitosan was used. The Lactobacillus plantarum strains were used as control. The inoculants (1 × 107 cfu/g) alone or in combination with inulin or in combination with enzymes were added to chopped forages and ensiled in 1.5-L anaerobic jars.
    Conclusion: Combination of the isolates Lactobacillus and Enterococcus with inulin and enzymes can improve the aerobic stability of corn silage.

  • XML | PDF | downloads: 470 | views: 540 | pages: 187-190

    Background and Objective: Genital warts, due to specific types of the human papillomavirus, have long been regarded as one of the most important causes of cervical cancer and one of the most common cause of Sexually Transmited Diseases (STDs).  Over the years, it has been the focus of several studies in order to find the best effective approach to eradicate the virus, however there are still controversies regarding this matter. We compared efficacy of the two physical ablative therapies; Liquid Nitrogen and CO  laser.
    Material and Methods: One hundred and sixty patients, with external genital warts, were divided into two groups.  Each group consisted of 80 patients treated with CO -laser or cryotherapy. Clearance and recurrence rates were evaluated for 3months.
    Results: Complete clearance was achieved in 76 lesions (95%) treated by CO -laser and 37  lesions (46.2%) treated by cryotherapy which was significantly different (p < 0.001). In the CO -laser group, lesions required only one treatment to clear while in the cryotherapy group, lesions required two (12%) even up to three (12.2%) treatments  for some patients  to clear completely. Laser therapy was associated with less recurrence rate compared to cryotherapy (0.05% Vs 0.18%).
    Conclusion: Generally, the efficacy of CO  laser treatment of external genital warts was approximately two fold greater than cryotherapy and it was associated with lower recurrence rate.

  • XML | PDF | downloads: 206 | views: 636 | pages: 191-197

    Background and Objectives: Varicella–Zoster virus (VZV) is a human herpes virus that usually attacks young children and commonly causes chicken pox (Varicella). Following primary infection, a lifelong latent infection is established. The virus often reactivates during adulthood or senesces to cause shingles (Zoster). Little is known regarding the genotypes of Varicella in Kuwait. The aim of this study was to genotype Varicella samples collected from patients in Kuwait.
    Materials and Methods: Samples from 60 cases of chicken pox were typed. The DNA extraction was performed using the commercially available DNA extraction kit. Two sets of oligonucleotide primers were used to amplify the intervening sequences with polymerase chain reaction to identify VZV DNA in clinical samples. The BglI and PstI endonucleases were used to digest. The PCR amplicons for PCR-RFLP typing.
    Results: Relatively consistent restriction enzyme digestion profiles for different VZV strains were observed. Limited genetic differences between VZV samples were found. Three VZV strains were identified (A, B and C) with type B representing 86.6%, type A 11.7% and type C being 1.7%. We found that distinct restriction fragment length polymorphism isolates from the same origin or nationality were very similar.
    Conclusion: Varicella strains with cutting sites for both enzyme PstI and BglI (typeB) were more prevalent. Molecular amplification of viral DNA by PCR and restriction digestion could be used for VZV typing as an alternative method to serological assays.

  • XML | PDF | downloads: 217 | views: 306 | pages: 198-203

    Background and Objectives: Nosocomial infections are usually acquired during hospitalization. Fungal infection of the urinary tract is increasing due to predisposing factors such as; antibacterial agents, indwelling urinary catheters, diabetes mellitus, long hospitalization, immunosuppressive agents, use of IV catheters, radiation therapy, malignancy. The aim of our study was to determine the prevalence of candiduria and urinary tract infection in patients admitted in Golestan and Emam Khomeini hospitals of Ahvaz, Iran.
    Materials and Methods: During 14 months, a total of 744 urine samples were collected and transferred to medical mycology laboratory immediately. Ten µl of uncentrifuged sample was cultured on CHROM agar Candida plates and incubated at 37°C for 24-48h aerobically. Candida species were identified based on colony morphology on CHROM agar Candida, germ tube production and micro-morphology on corn meal agar including 1% Tween 80.
    Results: In the present study, 744 hospitalized patients were sampled (49.5%, female; 50.5%, male). The prevalence of candiduria in subjects was 16.5% that included 65.1% female and 34.9% male. The most common isolates were C. albicans (53.3%), followed by C. glabrata (24.4%), C. tropicalis (3.7%), C. krusei (2.2%), and Geotrichum spp. (0.7%) Urine cultures yielded more than 10,000 yeast colonies in 34.1% of cases, and the major predisposing factor associated with candiduria was antibiotic therapy (69.1%).
    Conclusion: Candiduria is relatively common in hospitalized patients in educational hospitals of Ahvaz. In addition, there is a strong correlation between the incidence of candiduria in hospitalized patients and broad-spectrum antibiotics therapy.

  • XML | PDF | downloads: 312 | views: 793 | pages: 204-209

    Background and Objective: Candidiasis is a common opportunistic infection in HIV-infected patients. The spectrum of Candida infection is diverse, starting from asymptomatic colonization to pathogenicforms. The low absolute CD4+ T-lymphocyte count has traditionally been cited as the greatest risk factor for the development of Oropharyngeal Candidiasis and current guidelines suggest increased risk once CD4+ T lymphocyte counts fall below 200 cells/μL. Gradual emergence of non-albicans Candida species as a cause of refractory mucosal and invasive Candidiasis, particularly in patients with advanced immunosuppression and problem of resistance to azoles and other antifungal agents in the Candida species is a point of concern.
    Materials and Methods: A prospective study was carried out over a period of 2 years (2010-2011) on patients suffering from AIDS for the presence of Candida infection. After thorough clinical examination relevant specimens were collected and processed specifically to ascertain Candida infection. Speciation of Candida isolates and antifungal sensitivity testing was also done. The CD4 cell counts of all the patients were estimated and correlated with the presence (or absence) of candidiasis.
    Results: Out of a total of 165 HIV positive patients, a definitive diagnosis of candidiasis was made in 80 patients. Candida albicans was the most common yeast isolated. Patients with candidiasis had CD4 counts less than 200 cells/mm3. Maximum resistance was seen with fluconazole while no resistance was seen with voriconazole.
    Conclusion: The most common opportunistic fungal infection in HIV positive patients is candidiasis, affecting the mucocu- taneous system mainly but the invasive form is also common. Resistance to azoles and other antifungal agents in the Candida species is a point of concern.

  • XML | PDF | downloads: 209 | views: 284 | pages: 210-214

    Background: Orbital mucormycosis caused by Zygomycetes is a rare and fatal infection that generally affects the patients who  are  immunocompromised.  Despite  antifungal  therapy  and  aggressive  surgical  intervention,  mucormycosis  can cause serious and rapidly fatal infections if delayed diagnosis or therapeutic management occurs. Here, we report orbital mucormycosis in a healthy boy, with a favorable outcome after aggressive treatment. He has had no recurrence since the end of his treatment.
    Case present: A 2-year old healthy boy, some days after entry of dust particle to his left eye presented with swelling and redness of the eye. With diagnosis of “periorbital cellulitis” intravenous antibiotics vancomycin (40 mg/kg/day) and ceftriaxone (75 mg/kg/day) were started but no improvement was observed. The results of biopsy and tissue culture led us to a diagnosis of mucormycosis. Orbital exenteration, combined with intravenous amphotericin B (1 mg/kg/day), resulted in the patient’s survival.
    Conclusion: Due to the high mortality rate of mucormycosis, early diagnosis based on clinical findings and biopsy could be effective for management of the patients suffering from this infection.