Novelty in Biomedicine

Cancer is one of the leading causes of mortality and morbidity worldwide. Nisin consists of various and uncommon amino acids as an antimicrobial protein synthesized by the Lactobacilli genus. The current systematic review aimed to evaluate the anticancer activity of Nisin, an antibacterial peptide, on different human cancer cell lines. We searched PubMed/Medline and Embase databases to detect the studies addressing the cytotoxic activity of Nisin on human cancer cell lines. Our study was conducted following the "PRISMA" guideline. Of 202 potentially relevant articles, 15 studies met the inclusion criteria and were included for further analysis. The results revealed that Nisin has different levels of anticancer activity on human cancer cell lines. The outcomes of our review indicate that some cancer cell lines, such as cell skin carcinoma (A431), Melanoma cells (A375), and colorectal cancer cell lines (LS180), are strongly affected by the anticancer properties of Nisin. In contrast, the anticancer effect of Nisin on others like Human promyelocytic leukemia (HL60) is lower. Nisin shows significant anticancer effects in different cancer cell lines. Utilizing Nisin simultaneously with other antitumor agents can enhance its anticancer features and efficacy. Further studies, especially in vivo assay and clinical trials, are recommended to achieve more accurate results in this field.

Background: Health care workers (HCWs) are more likely to get latent tuberculosis infection (LTBI) because of
the direct contact they may have with patients and carriers. Therefore, this study aimed to assess the prevalence
of LTBI in HCWs.
Materials and Methods: In the present study, we searched from 1st 2010 to the end of 2021 in various databases
such as; PubMed, Scopus, Web of sciences, and Google Scholar for studies presented LTBI in HCWS. After
applying inclusion and exclusion criteria and quality assessment, obtained data were analyzed by Comprehensive
Meta-analysis (CMV) software.
Results: In total, 22 studies met the eligibility criteria to include in the present systematic review and metaanalysis. The combined prevalence of LTBI was reported by 25.9% (95% CI: 19.3-33.7). No publication bias
was seen among studies included based on Eger’s regression test (p=0.04).
Conclusion: Our study showed a high prevalence of LTBI in HCWs. Therefore, periodical screening of HCWs
with Suitable tests is essential to prevent this high prevalence. According to the results of this systematic
review and meta-analysis, the rate of LTBI in Iranian HCWs is high. Therefore, periodical screening and
diagnostic tests such as TST are necessary for the timely diagnosis and treatment of these individuals to prevent changing LTBI to an active form of tuberculosis.

Background: Echinococcosis/hydatidosis is one of the most important zoonotic diseases. The definitive hosts for Echinococcus granulosus (E. granulosus) include a wide variety of the Canidae and dogs. Early detection of Echinococcosis in dogs is the most influential factor in improving the prevention and control of hydatidosis. The primary purpose of the present study was to optimize the real-time quantitative PCR to diagnose E. granulosus infection in dogs before the disposal of eggs.
Materials and Methods: Three puppies were selected to be inoculated by 70000 protoscoleces. Normal saline was inoculated to the other two puppies chosen as an experimental negative control group. Ten privately owned healthy puppies were selected for the natural negative control group. Stool samples were collected on days 7, 14, 21, 28, and 35 post-infection, DNA was extracted, then a 287bp fragment of tandem repeat region gene was amplified and cloned into linearized TA vectors. Serial dilutions of recombinant plasmid DNA and a standard curve were established. The copy amount of DNA in each sample was determined based on the standard curve.
Results: The minimum time copro –DNA could be detected in the stool sample was found on the 7th day post-infection, which was equal to 9750×10-8 copy number or 9.75 pg of DNA. The assay was linear in 105 to 108 copies of the recombinant plasmid per microliter.
Conclusion: The real-time PCR assay diagnosed the infection eight days earlier than the copro antigen ELISA method (7 days versus 15 days, respectively).
Conclusion: The real-time PCR assay diagnosed the infection eight days earlier than the copro antigen ELISA method (7 days versus 15 days, respectively).

Background: Orexins regulate the body's energy balance during lactation. Also, Orexin A has been reported to have lipogenic effects on adipose tissue, but its role in the mammary glands is unclear. Acetyl CoA carboxylase (ACC) and glucose 6-phosphate dehydrogenase (G6PD) is critical lipogenic enzymes that catalyze the rate-limiting steps in milk fatty acid synthesis. This study was performed for the first time to investigate the effects of blocking the function of orexin-A in lactating female rats on the gene expression of mammary lipogenic enzymes and possible interaction with serum insulin hormone.
Materials and Methods: Orexin A receptor antagonist (SB-334867-A) was injected at three doses of 1, 2, and 4 μg/kg BW, in a volume of 50 μl solvent by intra-ductal method into the mammary glands of lactating rats and breast tissues were taken after eight hours. Serum insulin levels using ELISA and the relative expression of mammary ACC and G6PD were measured.
Results: Quantitative PCR results showed that by injecting 4 μg/kg BW of SB intra-ductally, a parallel decrease in the gene expression of ACC and G6PD and serum insulin levels was observed compared with the control group.
Conclusion: Blocking the function of orexin-A in the lactating rats decreased the expression of lipogenic mammary enzymes and serum insulin.

Background: There has been an increasing concern regarding high morbidity and mortality rate among patients with severe and complicated urinary tract infections (UTIs) and their related complications. Hence, there is a great demand for choosing the best treatment protocol. In the study, we evaluated and compared the efficacy of piperacillin/tazobactam and amoxicillin/clavulanic acid for treating complicated urinary tract infections.
Materials and Methods: This study enrolled 42 patients suffering from UTIs referred to Labbafinezhad hospital, Tehran, Iran. Subjects were randomly assigned to receive intravenous piperacillin/tazobactam or intravenous amoxicillin/clavulanic acid. Clinical manifestations, vital signs, laboratory parameters, and drug side effects within three days of completing the treatment protocols were evaluated and compared between the two groups. Data analysis was performed using SPSS version 16.0. A P-value of less than 0.05 was considered significant.
Results: There was no significant difference in the frequency of pyuria and hematuria between the two groups before and after the intervention. The frequency of positive urine cultures for extended-spectrum beta-lactamase bacteria, Escherichia coli, was also similar between patient groups before intervention. However, a statistically significant difference in the rate of positive urine cultures for Klebsiella was found between the two groups. There was no significant difference between the two groups in terms of clinical signs and symptoms, including fever, dysuria, frequency, pain intensity, supra-pubic pain, or nausea and vomiting before the intervention, as well as within 72 hours after treatment. The vital signs were also similar between these two groups. No drug side effect was found among patients.
Conclusion: Blocking the function of orexin-A in the lactating rats decreased the expression of lipogenic mammary enzymes and serum insulin.
Conclusion: Using piperacillin/tazobactam or intravenous amoxicillin/clavulanic acid was effective and safe for treating complicated UTIs. Clinicians should consider the cost and availability of these drugs to choose the most appropriate treatment for the patients.

Background: The severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) attaches to the angiotensin-converting enzyme-2 (ACE-2) receptors for penetrating cells. Because these receptors are extensively distributed in the intestine, coronavirus disease 2019 (COVID-19) may cause gastrointestinal (GI) symptoms. Helicobacter pylori (H. pylori) is known to increase the expression of ACE-2 receptors in the GI tract. This study aimed to investigate the prevalence of H. pylori infection and its associated factors in patients with COVID-19.
Materials and Methods: This cross-sectional study was conducted from February to December 2021. A total of 215 patients who had been diagnosed with COVID-19 infections using a real-time PCR test or a CT scan were included in the study. The enzyme-linked immunosorbent assay (ELISA) test on serum samples was used to evaluate the presence of H. pylori.
Results: All 215 positive patients for COVID-19 with a mean age of 59.72±17.23 were evaluated. Among them, 153 patients (71.2%) were H. pylori-positive. Moreover, H. pylori+/ COVID-19+ group showed higher mean age than H. pylori-/ COVID-19+ patients. However, there was no significant difference between the two groups of patients regarding their medical background, drug history, BMI, and disease severity. The prognosis of the patients was severely worse in the H. pylori+/ COVID-19+ than in H. pylori-/ COVID-19+ patients.
Conclusion: Our study adds to the previous findings and provides evidence regarding the high prevalence of H. pylori in COVID-19 patients. These investigations could help us elucidate the relationship between H. pylori and respiratory system findings and better understand COVID-19.

Background: This study aimed to determine carbapenems, colistin resistance genes, and antimicrobial susceptibility profiles of Pseudomonas aeruginosa and Acinetobacter baumannii isolates.
Materials and Methods: In this cross-sectional study, specimens of patients with bloodstream, urinary tract, and surgical site nosocomial infections were enrolled. P. aeruginosa and A. baumannii isolates were identified using conventional methods. Antimicrobial susceptibility testing (AST) on isolates was performed using the disk diffusion method and minimum inhibitory concentration (MIC) for colistin as recommended by the Clinical and Laboratory Standards Institute (CLSI). The combination meropenem disk method was used to detect metallo-β-lactamases (MBLs). The blaNDM, blaVIM, blaIMP, and mcr-1 genes were identified using the polymerase chain reaction (PCR) method and Sequencing.
Results: Forty strains of P. aeruginosa and forty strains of A. baumannii were isolated from hospitalized patients. The overall prevalence of multidrug-resistance (MDR) was 50% and 95% in P. aeruginosa and A. baumannii isolates, respectively. Almost all the MDR isolates were resistant to cefepime and piperacillin. Colistin had significant inhibitory activity against the isolates. MBL was detected in 25.0% and 15.0% of clinical isolates of P. aeruginosa and A. baumannii, respectively. We detected no blaNDM, blaVIM, blaIMP, and mcr-1 genes in our A. baumannii isolates. Moreover, only three P. aeruginosa isolates were positive for blaIMP gene.
Conclusion: The alarming proportion of MDR P. aeruginosa and A. baumannii isolates was reported in the current study. Effective infection prevention practices are required and AST should guide patients' treatment.

Background: Rhodotorula mucilaginosa and Candida glabrata have emerged as potential pathogens,
particularly in immunosuppressed hosts. This study aimed to present a case of coinfection of Candida glabrata
and Rhodotorula mucilaginosa in a 35-year-old immunosuppressed female with onychomycosis on the first and
second left toenails.
Cases Report: Causative agents were identified according to morphology, microscopic studies, culture, and
DNA molecular analysis. Candida glabrata demonstrated high minimum inhibitory concentrations against the
tested antifungals except itraconazole. Moreover, Rhodotorula mucilaginosa had shown low minimum
inhibitory concentrations against clotrimazole and ketoconazole at a dilution of 0.25 μg/ml. Itraconazole is
administered at 200 mg twice daily for one week for toenails and as pulse treatment (for one week a month) at
5 mg/kg daily with topical clotrimazole.
Conclusion: Clinical improvement was noted in the patient's clinical examination after ten months. Information
about the increasing resistance to antifungal agents helps decide antifungal prophylaxis and select the empirical
therapy for cancer patients.