Jundishapur Journal of Microbiology
Volume:13 Issue: 9, Sep 2020

 Tuberculosis is one of the most frequent and persistent global diseases causing millions of deaths every year. Pakistan lies at number 6 among the 22 most dominant countries, with multidrug resistance up to 15%. Isoniazid-resistant strains of Mycobacterium tuberculosis are gradually rising and seem to be more prevalent in developing countries. Mutations in the katG gene are considered to be responsible for the accusation of isoniazid resistance in M. tuberculosis.

 The current study was designed to investigate the structural and functional associations of KatG gene mutations (S315R and S315T) and multidrug resistance in M. tuberculosis isolates from Karachi, Pakistan.

 The present study revealed conformational changes in the structure of the KatG enzyme due to observed mutations, which led to induced alterations in isoniazid binding residues at the active site of the KatG enzyme. Furthermore, substantial changes were observed in interaction energy, ligand-receptor energy, electrostatic energy, salvation energy, and ligand-receptor conformational entropy. All these resultant modifications due to S315R and S315T mutations ultimately reduced the flexibility and stability of proteins at isoniazid-binding residues.

 This deviation in the consistency of protein texture eventually compromises the enzyme activity. It is well expected that the outcomes of the current study would provide a better understanding of the consequences of these mutations and provide a detailed insight into some previously unknown features.

 Invasive fungal infection received more and more attention because of its high mortality, Candida albicans and Aspergillus fumigatus is the most common pathogenic fungus for systematic fungal infection, A. lentulus was isolated and identified recently and named as a sister of A. fumigatus.

 The current study aimed to explore the concentration and time-dependent relationships of the virulence of fungi due to the change in the interleukin-1 beta (IL-1β) level.

 Candida albicans, A. fumigatus, and A. lentulus suspensions with a multiplicity of infection = 0, 1, 5, 10, and 20 units were used to treat mouse dendritic cells. The IL-β level was measured by enzyme-linked immunosorbent assay (ELISA) at 2, 6, 12, 24, and 48 hours after the treatment was administered.

 The main effects and interactions between the multiplicity of infection, intervention duration, and the dependent variable of IL-1β were significant. Besides, there were statistically significant differences. Only C. albicans and A. lentulus could induce IL-1β 48 hours after administration. Furthermore, the production of IL-1β induced by A. fumigatus was higher than that induced by A. lentulus and C. albicans.

 This study demonstrated concentration- and time-dependent relationships in IL-1β production by dendritic cells induced by three types of fungi. Candida albicans and A. lentulus exhibited a slow phase-in in vitro inflammation induction. The inflammatory response induced by A. fumigatus in vitro has the characteristics of a short action time and a strong toxic effect. Finally, A. lentulus is less virulent than A. fumigatus, and its inflammation-inducing time is relatively longer.

 Human Papillomavirus (HPV) is a DNA virus with more than 100 genotypes, at least 12 of which are high-risk and associated with high-grade cervical lesions. Data on the prevalence of high-risk HPV genotypes among women are not yet available for the total regions of Iran.

 The present study aimed to determine the prevalence of high-risk HPV types among women screened for cervical carcinoma in Yazd and compare the cytology, histology, and colposcopy results.

 In this cross-sectional study, 402 women referring to gynecology clinics of Shahid Sadoughi University of Medical Sciences, Yazd, Iran, were selected. The Pap smear and HPV typing were performed on cervical samples. The high-risk HPV types were detected by the polymerase chain reaction (PCR)-based reverse blot hybridization assay. Colposcopy was carried out on patients with high-risk HPV types, and biopsies were taken for histological examination.

 Among 402 women screened by HPV-PCR, 32 (7.97%) women were positive for high-risk HPV types. Human papillomavirus 16 and HPV18 were the most frequent genotypes (46.9%). The cytology, histology, and colposcopy results were abnormal in 56.2%, 29.1%, and 71.9% of patients, respectively. Pap smear had 100% sensitivity and 58.3% specificity for the detection of high-grade cervical lesions, while these values for colposcopy were 75% and 87.5%, respectively.

 The frequency of high-risk HPV types was relatively low among women living in Yazd than in those from other provinces of Iran. A significant percentage of patients with HPV had normal cervical cytology and histology. Therefore, HPV typing is recommended to decrease the development of cervical cancer. Colposcopy had acceptable sensitivity and specificity for the detection of high-grade cervical lesions.

 In December 2019, a new coronavirus appeared in China, as a cause of acute respiratory disease. Healthcare Workers (HCWs) in children's hospitals are one of the groups who are at a high rate of exposure to COVID-19 patients. The detection of antibodies is useful and helps diagnose late or recent SARS-CoV-2 infection. Most children may present with asymptomatic or mild SARS-CoV-2 infection and can be silent sources of infection in the community and hospitals.

 This study was conducted to determine the antibodies (IgM and IgG) against SARS-CoV-2 in Mofid children's hospital staff.

 This cross-sectional study evaluated 475 staff from Mofid children's hospital from April 20 to May 5, 2020, in Tehran. We collected blood samples for the antibody assay with a rapid test kit. A questionnaire was used to collect demographic and clinical data.

 Of 475 staff who participated in this study, 25 (5.3%) were diagnosed with COVID-19 by Polymerase Chain Reaction (PCR) and/or CT scan. Besides, 140 (29.4%) of them were positive for IgM and/or IgG SARS-CoV-2 antibodies.

 The seropositivity of antibodies against SARS-CoV-2 among children's hospital staff was higher than expected. Approximately 5% of the participants were diagnosed as definitive positive COVID-19 cases by PCR and/or CT scan, but 29.4% of them were seropositive. The difference is a warning, as it shows seropositive people could be silent sources of transmission during asymptomatic infection.

 Candida albicans is one of the most important members of the human normal flora that can cause opportunistic fungal infections. Hydrolytic enzymes are one of the main virulence factors in the pathogenesis of Candida species.

 This study was carried out to determine proteolytic activities, and their related gene expressions in C. albicans isolates obtained from oropharyngeal candidiasis in head and neck cancer patients.

 Thirty-two C. albicans clinical isolates were included in this study. Secreted aspartyl protease and phospholipase activities were analyzed by appropriate agar media and precipitation zones. The expression levels of SAP1, 3 and PLB1, 2 genes were evaluated by real-time PCR.

 All the 32 isolates exhibited proteinase activity while 28 of them showed phospholipase activity. All the strains possessed all SAPs genes; however, PLBs genes were not expressed in four isolates.

 Our findings demonstrated that the clinical strains of C. albicans had strong proteolytic activity and high expression levels of the pertaining genes.

 As known, there is a high correlation between Helicobacter pylori infection and gastric carcinoma.

 Concerning the important role of adhesin HpaA of H. pylori in the infection process, we aimed to explore whether HpaA promotes gastric cancer metastasis.

 In this study, the levels of IL-21, MMP-2, and MMP-9 in patients’ biopsies with H. pylori infection were compared with post-treatment condition. The levels of IL-21 from CD4+ T cells and culture supernatants with the recombinant HpaA treatment were detected, and then the levels of MMP-2, MMP-9, and metastasis were detected and verified via AGS cells co-cultured with aforesaid CD4+ T cells.

 Our results showed that higher levels of IL-21, MMP-2, and MMP-9 in patients’ biopsies with H. pylori infection than without H. pylori infection. Adhesin HpaA induced more IL-21 via CD4+ T cells, and IL-21 induced high MMP-2 and MMP-9 via AGS cells. In particular, HpaA caused this serial reaction to improve the migration of AGS cells, and aptamer HA6 (our previous report) and anti-IL-21 mcAb reduced the above phenomenon remarkably.

 In summary, our research suggested that adhesin HpaA plays a significant role in the process of gastric carcinoma cell metastasis via IL-21 from HpaA-induced T cells, and aptamer HA6 may be a potential therapeutic agent for H. pylori treatment.

 Urinary tract infections (UTIs) are the most common infections in the community and in hospitalized patients.

 To investigate the epidemiology and antimicrobial susceptibility pattern of uropathogens and determine the appropriate empirical antibiotics to treat UTIs in the community and hospitalized patients.

 A total of 2,485 urine cultures were performed at Mogadishu Somali Turkish Training and Research Hospital. Through the standard Kirby-Bauer disk diffusion method and commercial disks, antimicrobial sensitivity and resistance were studied based on the Clinical and Laboratory Standards Institute (CLSI) system using Mueller-Hinton agar. The identification of the microorganisms was done using eosin methylene blue agar and blood agar.

 Escherichia coli was the most predominant pathogen (63.4%) in all age groups, both genders, and in the community and hospital-acquired UTIs, followed by Klebsiella pneumonia (13.3%). Ceftriaxone, trimethoprim/sulfamethoxazole, ampicillin, cefuroxime, and cefixime revealed the highest resistance level (82-100%) against uropathogens. Ciprofloxacin (67.7%) and levofloxacin (54.2%) showed increasing resistance rates against uropathogens. Tigecycline, colimycin, vancomycin, and teicoplanin exhibited the most powerful sensitivity rate (100%). Moreover, fosfomycin, nitrofurantoin, and amikacin manifested a significant sensitivity rate ranging from 86% - 95%. Acinetobacter baumannii was the most prevalent pathogen that belonged to multidrug- and extensively drug-resistant patterns in 69.1% of the samples. Escherichia coli and K. pneumonia showed similar multidrug-resistant patterns in 35.2% of the cases.

 The results indicated increased trends of antimicrobial resistance rate in trimethoprim/sulfamethoxazole (85.1%) and fluoroquinolones (61%) against E. coli that was higher than the recommended local resistance rate for empirical therapy (< 20% and < 10%, respectively). According to the results, using fosfomycin and nitrofurantoin are suggested for UTI empiric treatment, and other antibiotics should be prescribed carefully.

 Moxifloxacin is recommended for empirical antibiotic treatment of patients with cirrhosis. However, due to a lack of clinical safety data on moxifloxacin in Child-Pugh C patients, it is unknown how to use moxifloxacin in clinical practice.

 A 76-year-old female with decompensated cirrhosis developed pneumonia during hospitalization. She had an initial failure to respond to imipenem/cilastatin + linezolid therapy. After three-day therapy with imipenem/cilastatin + moxisaxin, her infection symptoms rapidly improved. At this time, she presented a poor response with suspected hepatic encephalopathy. Given the worsening clinical symptoms caused by drug hepatotoxicity, moxisaxin was discontinued. Then, her body temperature rapidly raised.

 Moxisaxin may be a potentially useful antibiotic for hospital-acquired pneumonia in patients with decompensated cirrhosis, but further studies are needed to validate its hepatotoxicity.