Journal of Cellular, Molecular and Biomedical Reports
Volume:1 Issue: 2, Spring 2021

Finding efficient therapeutic strategies to fight antibiotic-resistant bacteria is a complicated affair specifically in the therapy of chronic bacterial infections related to hospital-acquired infections. Recently, three major antibacterial systems based on antisense RNA, CRISPR-Cas9, and metal/metal oxide nanoparticles particularly silver (Ag) nanoparticles have shown more effective antibacterial activity compared to conventional antibiotics. ROS generation, attachment to the cell membrane, disruption of bacterial envelop, inactivation of electron transport chain, decreasing the local pH, modulation of cell signaling, and denaturation of biological macromolecules such as proteins and nucleic acids have been found as the main antibacterial functions of Ag nanoparticles.  Antisense RNA, a single-stranded RNA, can hybridize with complementary genes in messenger RNA (mRNA) followed by blockage translation of these genes into proteins. Moreover, CRISPR (clustered regularly interspaced short palindromic repeats) is a family of viral DNA sequences derived from bacteriophages, which can target and destroy foreign DNA by nuclease activity. There are 2 classes and 6 subtypes (I-VI) of CRISPR-Cas systems, which may be engineered as potential antibacterial agents to target specific sequences. Therefore, here, recent advances and challenges for the antibacterial application of these three therapeutic agents are presented.

Emerging antibiotic resistance in microorganisms particularly multidrug-resistant strains among bacteria are increasing because of misusing antibiotics as well as evolution of antibiotic resistance mechanisms. In this regard, Acinetobacter baumannii is one of the six most common multidrug-resistant microorganisms in hospitals. Recently, carbapenems, as common antibiotics to treat infections of Acinetobacter have not an acceptable efficiency because of the resistance emergence to these antibiotics in many strains.  In this study, resistant strains of A. baumannii were isolated and identified as an appropriate preventive strategy to reduce infections in hospitals. Disc diffusion test and PCR method were used to isolate of resistant strains and identify beta-lactamase genes of blaAmpC, blaTEM, blaVIM, and blaSHV. This study showed that these genes were contributed in antibiotic resistance with about 18.4% and ≥53.5% strains expressing all 4 genes and ≥3 genes, respectively. The blaAmpC gene is more prevalent than other genes, and this is probably due to the prevalence or rapid transfer of this beta-lactamase. However, more studies should be performed in a comparative way to isolate and identify other antibiotic-resistant bacterial strains relate to other hospitals.

The main purpose of microbial typing is to evaluate the relationships between microbial isolates. Microbial typing can use for identifying the source of infection by detecting a clonal link between the strains. Moreover, it can analyze outbreaks, antimicrobial-resistant strains, and evaluate the effectiveness of control measures so, the efficiency of monitoring systems would increase. HAIs can affect hospitalized patients in all age ranges with any clinical situation, and lead to death. Molecular epidemiology is useful to determine genetic relatedness between isolated pathogens from patients, and design proper prevention plans to prevent infection through the hospital and community. Nowadays, typing methods for a wide range of bacterial strains are known as essential epidemiological tools to prevent and control infections in hospitals and communities. Although basic typing methods were more focused on phenotypic techniques like antibiogram and serotyping, new methods are based on molecular techniques including PCR-based methods and sequencing-based methods. Due to the high frequency of methods, choosing the right one for research applications seems difficult and requires basic knowledge about all of them. In this review, we aim to introduce the most useful and practical molecular typing techniques. Also, their utilization, advantages, and disadvantages were compared.

Staphylococcus aureus contains numerous surface proteins called microbial surface components recognizing adhesive matrix molecules (MSCRAMMs) that mediate binding to host tissues and initiate colonization leading to infection. Virulence genes such as enzymes, toxins, adhesin proteins, cell surface proteins play an important role in the pathogenicity of S. aureus strains. The distribution and prevalence of virulence genes vary among S. aureus strains in different regions. However, the highest frequency of virulence genes among S. aureus strains is related to toxin genes. There are many PCR methods for detecting these microorganisms such as conventional PCR, multiplex PCR, reverse transcription PCR (RT-PCR), and quantitative PCR (qPCR). Therefore, this study aimed to investigate the presence of virulence genes among methicillin-resistant S. aureus (MRSA) strains. In this study, multiplex PCR technique was applied to determine the presence of virulence genes among MRSA strains. Results showed the frequency of virulence genes among bacterial strains isolated from Al-Najaf Al-Ashraf teaching hospital. In addition, among the strains, hla gene with 91% frequency, exhibited the highest prevalence among pathogenic genes. Sea, mecA, clfB, femA, fnbB, tsst, hlb genes with 88%, 65%, 54%, 45%, 39%, 27% and 13% were in the next ranks, respectively. This investigation showed mecA is a gene found in bacterial cells that allows them to be resistant to antibiotics such as methicillin and other penicillin-like antibiotics.

A type of viral pneumonia that broke out in Wuhan, China in December 2019, and new strains of it are spreading rapidly around the world, is called coronavirus disease 2019 (COVID-19). The incidence of cardiovascular complications has increased both in the general population and in patients diagnosed with the disease during the COVID-19 epidemic. One of the conditions is stress cardiomyopathy, which may be related to COVID-19. During the COVID-19 epidemic, stress cardiomyopathy may be present as a complication of acute infection or as an indirect consequence of quarantine. These conditions have created complications in patient care that have led to increased adverse outcomes, hospitalization, and medical costs. Stress cardiomyopathy is caused by various emotional and physical stressors such as anger, sadness, happiness, surgery, multiple medications, general anesthesia, and infectious diseases. The outbreak of the new coronavirus has posed an ongoing challenge for these patients with several medical and economic consequences. Providing useful information on stress and COVID-19 to people with heart disease and their families can be very important, and also, education and psychotherapy of heart patients can reduce the number of hospitalization and their complications.

Changes in blood sugar in poisoning can be one of the most important determinants of the outcome of patients with poisoning. Since poisoning is one of the most common and increasing causes of death worldwide and one of the most critical medical emergencies, this study aimed to investigate changes in blood sugar in patients with acute poisoning and how patients' blood sugar can predict the severity and outcome of the disease. The present study was performed on 200 patients with acute drug poisoning referred to the emergency department of Amir Al-Momenin Hospital in Zabol from March 2018 to March 2020. Blood glucose levels of all patients were recorded at the time of admission and every hour to the first 5 hours after admission, and the results were entered in the information form of each patient. Finally, the data were entered into SPSS V22 software and statistically analyzed. The mean age of participants was 23.21 ± 12.80 years, and the minimum and maximum age of patients were 1 year and 77 years, respectively, and only 9.8% of them had a history of diabetes. In this study, the highest rate of intoxication with opioids such as methadone and tramadol was (38%), followed by benzodiazepines (20.5%), NSAIDs (19.5%), and SSRIs (7%) were the most commonly used drugs. The prevalence of hypoglycemia in this study was 3% (6 patients), while no cases of hyperglycemia were reported. In this study, most changes in blood sugar were caused by alcohol poisoning. Also, neuroleptics, NSAIDs, and chemicals had the least changes in blood sugar. However, patients' blood sugar at the beginning of poisoning did not affect patients' prognosis. The present study results showed that changes in blood sugar during treatment during drug intoxication, alcohol, medications(sulfonylurea, glibenclamide), and NSAID are very important, so regular monitoring of blood glucose in intoxication with these cases is essential.