bacteria

In COVID-19 pandemic we focused on epidemiology and somewhat we neglect the possibility of biochemical influencing of the infection. Therefore we try to find some properties of the virus, which are impressionable by drugs. Droplet infection transmission is mainly (hypochloric acid) by nose and mouth. Diseases of nose and paranasal sinuses are most often of viral or bacterial origin.

Interferons are multifunctional cytokines widely used in clinical settings as an anti-viral drug. In addition, interferon’s exhibit anti-cancer and anti-bacterial effects. Nearly two thousand papers related to interferon are published each year, which illustrates the importance placed by researchers on the study of interferon. This review focuses on recent advances in the study of interferon, particularly in the areas of its mechanism of anti-cancer effect and signal transduction. We also describe the tumor resistance to interferon and the side-effect of interferon-based therapy, which leads to an expectation of future research of interferon.

tRNA-dependent amidotransferases (AdT) are essential enzymes for protein biosynthesis in many bacteria and in all archaea. As AdT is essential for a number of pathogenic bacteria, and it is absent from mammalian cytoplasm, it is considered as a putative target for novel inhibitors that could be lead compounds to develop a new class of antibiotics. Besides GatFAB of Saccharomyces cerevisiae mitochondria and GatAB of Plasmodium falciparum apicoplast, all reported AdT can be divided into two groups: heterodimeric GatDE and heterotrimeric GatCAB. The latter is required to catalyze the conversion of Glu-tRNAGln and/or Asp-tRNAAsn into Gln-tRNAGln and/or Asn-tRNAAsn in many pathogenic bacteria. Recently determined high resolution crystal structures of several GatCAB could be used to design new inhibitors. In this review, we highlight the essential role of AdT for the faithful translation of glutamine and/or asparagine codons, we describe important features of the crystal structures of several GatCAB as well as tRNA/AdT/aaRS complexes for the formation of Gln-tRNAAsn and Asn-tRNAAsn, we finally summarize discoveries of AdT inhibitors based on their analogy to glutamine, adesosine tripoliphosphate and 3’-end of tRNA.

Background: Proteases are a group of enzymes that catalyze the cleavage of peptide bonds in proteins found in nature. Microbial protease constitutes one of the most important for industrial aplications. Proteases play a crucial role in numerous pathologic processes as well. KCl is an unnatural salt. The purpose of this study was to examine the effect of this salt on protease production under different agitation and heat conditions. Methods: The effects of KCl (rpm/heat) on the production of a protease, of E. coli, P. aeruginosa and E. faecalis strain, were investigated. The decrease in protease production at 37 °C was also observed in this work that proved that heat plays a major role in enzyme production. Results: The presence of KCl also caused a decrease in protease production in three bacterial species. The use of KCl appears to be a viable alternative when it is necessary to reduce protease activity outside of industrial applications (such as health care). This unique property makes it attractive and useful to be used in health industries. In the future we think that it will contribute to clarification of the matter in this way.

Objectives: To evaluate the colour stability of 3 recently developed resin based materials continuously exposed to various staining agents. Methods: 144 disc-shaped specimens were made of each of the 3 tested composites (Essentia, Brillant, Inspiro). Half of them were of 1mm thickness, the other half 1.2mm thickness. The thicker group was than polished up to 4000 grit and reduced to 1mm thickness, too. All specimens after 24 h dry storage in an incubator (INP-500, Memmert), received an initial colour measurement by means of a calibrated reflectance spectrophotometer (SpectroShade, MHT, Niederhasli, Switzerland). Specimens were then divided into 6 groups (n=6) and immersed in 5 staining solutions or artificial saliva (control). All specimens were kept in an incubator at 37°C for 28 days. Staining solutions (red wine, curry mixed water, curry mixed oil, tea and coffee) were changed every 7th day to avoid bacteria or yeast contamination. After 28 days of storage spectrophotometric measurements were repeated and L*a*b* scores once more recorded to determine the colour (ΔE00) changes. Results: All tested materials showed significant color changes after 28 days staining immersion. When considered over a black background ΔE00 of polished samples varied from 1.7 (Brillant/distilled water) to 24.1 (Brillant/wine). When considered over a white background ΔE00 of polished samples varied from 1.1 (Essentia/distilled water) to 32.5 (Inspiro/wine). When considered over a black background ΔE00 of unpolished samples varied from 1.1 (Essentia, Inspiro/distilled water) to 25.8 (Essentia/wine). When considered over a white background ΔE00 of unpolished samples varied from 1.4(Inspiro/distilled water) to 33.1 (Inspiro/wine). Conclusions: Staining of restorative materials seems to be dependent on the composition of the product itself. Unpolished samples demonstrated to be more prone to staining than the polished ones

Fifty nine isolates belonging to six species of Enterococci namely, Enterococcus faecalis, Enterococcus faecium, Enterococcus raffinosus, Enterococcus durans, Enterococcus mundtiiand Enterococcus avium (n = 35, 15, 4, 3, 1 and 1 isolates, respectively) were obtained from different clinical specimens including urine, pus, blood, wound, sputum and synovial fluid. The highest numbers of Enterococci were recorded from the pus (20 isolates, 33.90%) followed by urine (12 isolates, 20.34%) while the lowest frequency was observed with synovial fluid samples (2 isolates, 3.39%). These isolates showed different multidrug resistant patterns with the lowest resistant for linezolid (n = 5, 8.48%), followed by teicoplanin (n = 14, 23.73%) and vancomycin (n = 20, 33.90%) while they exhibited the highest resistant against penicillin (n = 53, 89.83%), oxacillin (n = 50, 84.75%), erythromycin (n = 49, 83.05%) and streptomycin (n = 47, 79.66 %). On the other hand, a free living marine bacterium under isolation code ESRAA3010 was isolated from seawater samples obtained from the fishing area Masturah, Red Sea, Jeddah, Saudi Arabia. The phenotypic, chemotaxonomic, 16S rRNA gene analyses and phylogenetic data proved that isolate ESRAA3010 is very close to Bacillus subtilis and then it was designated as Bacillus subtilis ESRAA3010. It gave the highest antagonistic activity against all clinical Enterococcus faecalis, Enterococcus faecium, Enterococcus raffinosus, Enterococcus durans, Enterococcus mundtiiand Enterococcus avium isolates under study with minimum inhibitory concentration (MIC) ranged from 4 to 56 µg/mL, 4 to 12 µg/mL, 4 to 8 µg/mL, 4 to 8 µg/mL, 8 µg/mL and 4 µg/mL, respectively as well as minimum bactericidal concentration (MBC) (8 to 64 µg/mL, 4 to 16 µg/mL, 4 to 12 µg/mL, 4 to 16 µg/mL, 12 µg/mL and 8 µg/mL, respectively). Moreover it showed anti-proliferative activity against colon (HCT-116), liver (HepG-2), breast (MCF-7) and lung (A-549) carcinomas with IC50 equal to 39, 50, 75 and 19 µg/mL, respectively which indicates its prospective usage in the upcoming decades.

Background: Klebsiella pneumoniae is a bacterial species that often causes infections in humans. Infections occur most frequently in hospitalised or immunocompromised patients and are treated with antimicrobials. In recent decades, K. pneumoniae has developed significant resistance to many antimicrobials. Objective: The main goal of this study was to determine the frequency of resistance of isolated K. pneumoniae strains from urine samples of hospital patients and outpatients, and to find evidence of ESBL strains and their resistance to certain antibiotics. Methods: During the study period, Klebsiella pneumonia was isolated from the urine samples of 430 patients. The procedure for processing of urine samples, identification, susceptibility toward antimicrobials and evidence of ESBL strains were carried out according to the recommended standards. Results: Of the total K. pneumoniae isolates, 153 (35.6%) were isolated from hospital patients and 277 (64.4%) from outpatients. Strains isolated from hospital patients were resistant to each tested antibiotic. ESBL strains were detected in 169 (39.30%) samples, 92 (60.13%) from hospital patients and 77 (27.8%) from outpatients. Conclusion: Strains of K. pneumoniae isolated from the urine of hospital patients and outpatients have developed significant resistance against all tested antibiotic substances. A higher occurrence of ESBL strains was observed in hospital patients than in outpatients. ESBL strains were resistant to all penicillins and almost all cephalosporins. Highly effective antimicrobials were amikacin, colistine, carbapenem and fosfomycin. The best therapeutic results were achieved when patients were treated with fosfomycin and imipenem.

The isolation of phytase using Pichia Pastoris under methanol/sorbitol co-feeding induction technique was investigated. The biological activity of extracellular phytase after optimization with co-substrates induction in 4 liters fermentor (NBS) increased to 13250 U/ml. This led to a 509 fold increases in comparison to the other type of phytase. This effect was studied via induction with sorbitol/methanol in fermentation by Pichia Pastoris GS115 (Mut+) at 20 °C. The interference of by products; methylal, hexamine and (S)-(+)-1,2-propanediol with release of phytase in Pichia Pastoris under methanol induction were detected and cannot be repressed by methanol induction alone. The TLC was used for glycerin analysis under methanol/sorbitol induction and the results were lesser compare to that obtained during phytase production under methanol induction alone. This work showed the higher expression of heterologous proteins and by fed batch fermentation; the expression identified an advantage of producing a significant activity of phytase. Practical applications Plant derived products including sorbitol have been used as alternative medicines for the therapeutic treatment of various diseases, food supplements and could be used in many manufacturing processes. It serves as a culture media for bacteria, and helps to distinguish the pathogenic E. coli O157:H7 from its most other strains. Cells growing on methanol require high oxygen consumption. Sorbitol was used as an alternative cheap co-feeding for the production of proteins and is a non-repressing carbon source for AOX1 promoter with no effect on the level of r-protein at its induction phase. This report describes the isolation of phytase using Pichia Pastoris under methanol/sorbitol co-feeding induction techniques, and sorbitol showed to be a promising co-substrate, as it could enhance both cell growth and targeted protein productivity. This co-feeding and fed-batch induction technique was used for recombinant phytase production in a small and large scale production and the metabolites were analyzed.

In 1955, nutrient malabsorption following upper gut surgery was shown to be related to altered upper gut microbiome. In individuals with abdominal symptoms after Roux-en-Y gastric bypass, we have reported that small intestinal glucose malabsorption is associated with upper gut bacterial overgrowth. We hypothesize that individuals with abdominal symptoms after vertical sleeve gastrectomy have glucose malabsorption associated with upper gut bacterial overgrowth, and to test this hypothesis, bacterial overgrowth and potential glucose malabsorption are examined after sleeve gastrectomy. This is a retrospective study of individuals with medically-complicated obesity who underwent sleeve gastrectomy from 2013 to 2016 with subsequent glucose hydrogen breath testing to evaluate abdominal symptoms. A fasting breath hydrogen or methane of ≥10 PPM or rise of ≥8 PPM ≤45 minutes after oral glucose is bacterial overgrowth, while glucose malabsorption is a second rise of ≥8 PPM at >45 minutes. Seven females (mean age: 48.0 years; mean body mass index at surgery: 45.7 kg/m2) are described. Five subjects (71%) have an early rise in hydrogen or methane, while three (43%) have a second rise in hydrogen or methane >45 minutes after glucose. The mean percent excess weight loss at one year was 40% in three individuals with a second peak and 46% in four subjects without a second peak. After sleeve gastrectomy, subjects have glucose malabsorption associated with the presence of bacterial overgrowth. Completion of a larger prospective study is needed to confirm and expanding upon these findings. Further work should examine the potential effects of bacterial overgrowth on expression of intestinal glucose transporters.

Objective: To assess the knowledge, attitudes and practices declared among general practitioners (GPs) concerning the use of antibiotics for the treatment of ARI in children under 5 years in Lubumbashi. Methods: A cross-sectional survey was conducted to assess the level of knowledge, attitude and practices concerning antibiotic prescribing among 67 GPs working in the pediatric setting in various health structures in Lubumbashi city, in the Democratic Republic of Congo. Data were collected from April 1st to June 30th, 2020. Results: GPs had limited knowledge about antibiotic prescriptions (mean of 46% correct answers to 8 questions). Although they are generally concerned about antibiotic resistance (mean ± SD = 0.50 ± 0.68), and are unwilling to submit to pressure to prescribe antibiotics to meet patient demands and expectations (mean ± SD = –1.78 ± 0.31) and the requirements to prescribe antibiotics for fear of losing patients (mean ± SD = –1.67 ± 0.47), there was a lack of motivation to change prescribing practices (mean ± SD = −0.37 ± 0.94) and strong agreement that they themselves should take responsibility for tackling antibiotic resistance (mean ± SD = 1.24 ± 0.74). Multiple linear regression results showed that higher knowledge scores were associated with less avoidance of responsibility when prescribing antibiotics (β = 0.919; p = 0.000). Conclusion: To curb the over-prescription of antibiotics, it is not enough to improve knowledge in itself. The lack of motivation of physicians to change must be addressed through a systematic approach. These data show the need for interventions that support the rational prescribing of antibiotics.

The process of hypothermia in the clinical setting has been practiced for 50 years and is known for its neuroprotective properties. This paper describes histopathological changes either by an ice sludge mimicking accidental hypothermia (S-group n=7) or by endovascular core-cooling (C-group n=7). Focal infiltrates of neutrophilic granulocytes were found in five of seven brains in the S-group and in one of seven brains in the C-group. These granulocytes were found in the arachnoids, in vessels, in vessel walls, and in the cerebral cortex. Fungi, bacteria, lymphocytes or plasma were not found. This experimental study, mimicking accidental hypothermia, reported histopathologic features of aseptic inflammation. To our knowledge, such findings have not been described in hypothermic animals or humans before. We suggest that a local inflammatory response may be triggered in such cases of hypothermia.

Sepsis refers to a generalized inflammatory response of the organism to an infection or to bacterial products in circulation, rather than the development of an infection per se. Despite recent advances in clinical practice and overall medical care, sepsis remains a great health care problem and is still the most common cause of death in critically ill patients with infection. We suppose that during the course of sepsis the expression of TRAIL in different organs correlates with acute mortality and further development of multiple organ dysfunction syndrome (MODS). It is expected that dendritic cells (DCs) might become targets for apoptotic processes in a result of elevated TRAIL expression. This hypothesis is a bias for detailed investigations for in vivo studies in animal models and for in vitro studies of septic patients.

Synthetic biology is an interdisciplinary branch of biology and engineering. The subject combines various disciplines from within these domains, such as biotechnology, evolutionary biology, molecular biology, systems biology, biophysics, computer engineering, and genetic engineering. Synthetic biology aims to understand whole biological systems working as a unit, rather than investigating their individual components and design new genome. Significant advances have been made using systems biology and synthetic biology approaches, especially in the field of bacterial and eukaryotic cells. Similarly, progress is being made with ‘synthetic approaches’ in genetics and animal sciences, providing exciting opportunities to modulate, genome design and finally synthesis animal for favorite traits.

Due to the advances in high-throughput sequencing technologies, the gut vriome is increasingly being perceived as one important component of the gut microbiome, where the number of viral biological entities is believed to far outcompetes that of the bacterial populations [1,2]. The human virome are primarily composed of bacteriophages, animal-cell viruses, endogenous retroviruses and viruses causing persistent and latent infections. Collectively they contains a more diverse genetic entity than the gut bacteria [3,4]. While the composition of them in the gut is precipitately being revealed, their roles in human health remain largely unexplored. It is undeniable that certain gut viruses are deleterious to human health. Interestingly, enteric viruses however, in some cases, can recapitulate the beneficial effects of commensal bacteria through different mechanisms, including modulating the innate and adaptive immunity of the host [5-7].

COVID-19 virus structural components: The 2019-nCoV, also called SARS-CoV-2, was first reported in Wuhan, China in December 2019. The disease was named Coronavirus Disease 2019 (COVID-19) and the virus responsible for it as the COVID-19 virus, respectively, by WHO. The 2019-nCoV has a round, elliptic or pleomorphic form with a diameter of 60–140 nm. It has single-stranded RNA genome containing 29891 nucleotides, a lipid shell, and spike, envelope, membrane and hemagglutinin-esterase (HE) proteins. Steps in progression of COVID-19 illness: Once inside the airways, the S protein on the viral surface recognizes and mediates the attachment to host ACE-2 receptors and gains access to endoplasmic reticulum. The HE protein facilitates the S protein-mediated cell entry and virus spread through the mucosa, helping the virus to attack the ACE2-bearing cells lining the airways and infecting upper as well as lower respiratory tracts. With the dying cells sloughing down and filling the airways, the virus is carried deeper into the lungs. In addition, the virus is able to infect ACE2-bearing cells in other organs, including the blood vessels, gut and kidneys. With the viral infestation, the activated immune system leads to inflammation, pyrexia and pulmonary edema. The hyperactivated immune response, called cytokine storm in extreme cases, can damage various organs apart from lungs and increases susceptibility to infectious bacteria especially in those suffering from chronic diseases. The current therapeutics for COVID-19: At present, there is no specific antiviral treatment available for the disease. The milder cases may need no treatment. In moderate to severe cases, the clinical management includes infection prevention and control measures, and symptomatic and supportive care, including supplementary oxygen therapy. In the critically ill patients, mechanical ventilation is required for respiratory failure and hemodynamic support is imperative for managing circulatory failure and septic shock. Conclusion: Confusion, despair and hopes: There is no vaccine for preexposure prophylaxis or postexposure management. There are no specific approved drugs for the treatment for the disease. A number of drugs approved for other conditions as well as several investigational drugs are being canned and studied in several clinical trials for their likely role in COVID-19 prophylaxis or treatment. The future seems afflicted with dormant therapeutic options as well as faux Espoir or false hopes. As obvious, not all clinical trials will be successful, but having so many efforts in progress, some may succeed and provide a positive solution. Right now, though, confusion and despair prevail.

Corona Virus Disease-2019 (COVID-19) has become one of the most serious diseases in the history of mankind. It has captured the entire world and solutions are yet to be discovered to fight this global crisis. The outcomes of COVID-19 are influenced by a variety of pre-existing factors. The secondary microbial infections are one of the prominent ones that are major contributors for Antimicrobial Resistance (AMR) as they warrant the use of antimicrobial medications. The present review aimed at exploring the potential relationship between AMR under such circumstances and COVID-19 related outcomes. The published literature across the globe has delineated that the impact of COVID-19 may have worsened by a great degree due to the presence of secondary infections majorly bacterial ones. The consequences of COVID-19 have been fatal and a significant proportion can be a major attributor to AMR, either directly or indirectly. Although, there is a dearth of studies that can establish a very strong and direct relationship between AMR and negative COVID-19 outcomes so in-depth research on this topic is required to further explain this relationship in detail. 

Hypoxis hemerocallidea Lam is one of the 43 Hypoxis species in South Africa, marketed extensively as over the counter herbal product for the management of several diseases. The plant commercial products link efficacy to hypoxoside 4, its aglycone (rooperol), or β-sitosterol. This study investigated antibacterial and anti-oxidant activities of four other molecules and two extracts from the Hypoxis plant. Visual antioxidant limit of detection and free radical scavenging activities of test samples were determined using 20 mM hydrogen peroxide, 0.4 mM DPPH or ferric reducing antioxidant power assay. Quantitative free radical was determine by spectrophotometric method while antibacterial activity was evaluated using MICs against uropathogens: S. aureus (ATCC25923), S. marcescens (ATCC 14041), P. aeruginosa (ATCC 9721), P. mirabilis (ATCC 33583) and E. coli (ATCC 10536). Anti-oxidant activities visual limit of detection of 0.06 mg/mL and percentage free radical scavenging activity (IC50 = 0.048 - 0.032 mg/ml) for pure compounds 1 - 4 and (IC50 = 0.037 - 0.039 mg/ml) for extracts were obtained. The reducing power IC50 ranged between 0.15 - 0.23 mg/ml for extracts and 0.11-0.35 mg/ml for standards. Antibacterial potentials show a noteworthy to moderate MIC values of 0.20 - 1.56 mg/ml against S. aureus (ATCC 25923), S. marcescens (ATCC 14041), P. aeruginosa (ATCC 9721), P. mirabilis (ATCC 33583) and E. coli (ATCC 10536). Galpinoside 5, hemerocalloside 3 and curculigoside C 2 are the other active compounds in Hypoxis plant.

Burns injuries induce a state of immunodepression that predisposes to a bacterial infectious complication that leads to several comorbid diseases and high mortality rate. Previous studies about anti-inflammatory, antimicrobial and antioxidant properties of Aloe vera (L.) Burm., Calendula officinalis L.and Matricaria recutita L. are acknowledge by antimicrobial effects. Previous studies about anti-inflammatory, antimicrobial and antioxidant properties of Aloe vera (L.) Burm., Calendula officinalis L. and Matricaria recutita L. are knowledge by antimicrobial effects. Bacterial cellulose membrane (nature BCM) is a potential carrier as a drug delivery system in the wound and burn treatment. The present study aimed to evaluate the antibacterial activity of extracts of A. vera, C. officinalis, and M. recutita incorporated in BCM against bacterial strains commonly present in wound and burns. The agar-dilution susceptibility testing was used to determine the minimum inhibitory concentration (MIC) for S. aureus, E. coli, and P. aeruginosa. The standardized extracts of A. vera, M. recutita, and C. officinalis were, respectively, used at 3.25% of total polysaccharides, 1% of apigenin 7-O-glucoside and 0.084% of total flavonoids expressed in quercetin. The BCM incorporated with A. vera extract was efficient to prevent the growth of P. aeruginosa and S. aureus. BCM loaded with C. officinalis inhibited the growth of S. aureus. The BCM loaded with A. vera and C. officinalis extract showed better antibacterial activities against P. aeruginosa and S. aureus and, consequently, properties to prevent infectious disease in the wound or burn caused by these bacteria.

Introduction: In Madagascar, plague is a highly contagious acute endemic infectious disease. The diagnosis of the most severe form of pneumonic plague remains difficult in children, hence the objectives of the present study; which is to identify the clinical signs of this clinical form in children and to describe its epidemiological and evolutionary profile. Methods: A retrospective case-control study was conducted in four pediatric wards in Antananarivo during the urban pneumonic plague outbreak from September 2017 to January 2018. Those cases were defined as children aged 0-15 years old suspected of having plague with positive RDT and PCR, and they were defined as children aged 0-15 years old with negative RDT and PCR. Results: Fifty-two cases of pneumonic plague were identified, half of which (50%) were under 24 months of age. A male predominance was noted with a sex ratio of 1.23 and 86.54% of the patients were from urban areas. Several clinical signs were found but none was specific for pneumonic plague: cough (59.62% p: 0.5), dyspnea (3.85% p: 0.16), chest pain (3.85% p: 0.26%), hemoptysis (7.69% p: 0.17), vomiting (9.62% p: 0.14), diarrhea (11.54% p: 0.45), altered general condition (38.46% p: 0.24%). Two deaths were noted (3.8%). Conclusion: No specific clinical warning signs have been identified in childhood pneumonic plague. In the event of an epidemic of urban pneumonic plague, any bacterial pneumonia should at least initially include active treatment against Yersinia pestis.

Bacteria has been known to grow in pipes of water distribution systems and bottled drinking water. Its growth in reusable drinking water bottles is not clear even though they have become more popular and used by children and adults daily everywhere. This study found that there is an extremely high level of bacteria content and a rapid microbial growth in reusable drinking water bottles. The bacteria content tested by heterotrophic plate count (HPC) is in a range of 0-2.4x105 CFU/mL with an average of about 34,000 bacteria counts/ml for bottles used by children and 75,000 bacteria counts/ml for bottles used by adults. Bacteria number can quickly increases to 1-2 million counts/ml in the bottles one day later. Considering the high level of HPC bacteria content in the reusable drinking water bottles, it may be necessary to have some control measures to reduce the bacteria level and to minimize the associated likely health risk of the disease spreading since many people use reusable water bottles every day.