- [Chronic granulomatous disease. Update and review]. [Journal Article]
- RARev Alerg Mex 2019 Apr-Jun; 66(2):232-245
- Chronic granulomatous disease (CGD) is a primary immunodeficiency syndrome which is characterized by increased susceptibility to severe fungal and bacterial infections. CGD is the result of the lack …
Chronic granulomatous disease (CGD) is a primary immunodeficiency syndrome which is characterized by increased susceptibility to severe fungal and bacterial infections. CGD is the result of the lack of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase enzyme in the patient's phagocytes to produce superoxide. It is characterized by recurrent infections with a narrow spectrum of bacteria and fungi, as well as a common set of inflammatory complications, including inflammatory bowel disease. The most frequently found pathogens are Staphylococcus aureus, species of Aspergillus, species of Klebsiella, Burkholderia cepacia, Serratia marcescens and species of Salmonella. Long term antibiotic prophylaxis has helped fight infections associated with chronic granulomatous disease, while the steady progress in bone marrow transplants and the possibility of gene therapy are defined as permanent treatment options.
- [Trials of the domestically produced nutrient medium «Agar Muller-Hinton II - Obolensk».] [Journal Article]
- KLKlin Lab Diagn 2019; 64(6):360-367
- The results of the comparative tests of the «Agar Muller-Hinton II - Obolensk» nutrient medium developed in SRCAMB, Obolensk, and the control nutrient medium imported «Mueller Hinton II Agar» are pre…
The results of the comparative tests of the «Agar Muller-Hinton II - Obolensk» nutrient medium developed in SRCAMB, Obolensk, and the control nutrient medium imported «Mueller Hinton II Agar» are presented in the study. The susceptibility of bacterial clinical strains to antimicrobial agents (AMP) was determined by the disc diffusion method and the method of gradient diffusion (E-test). The carbapenemase activity of the strains carrying the carbapenemase genes was determined by CIM-test. Total 173 characterized bacterial strains of species Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Proteus mirabilis, Serratia marcescens, Enterobacter aerogenes, Escherichia coli; Photorhabdus spp., Staphylococcus aureus, Enterococcus spp. were used in the study, including producers of OXA- and NDM-types carbapenemases for gram negative bacteria. A high degree of coincidence of the results obtained on both nutrient media was shown. The consistency index of the strain sensitivity categories to AMPs (S, I, and R) was 98.2% for the disc diffusion method, and 94.4-100% - for E-test and CIM-test methods. Thus, within the framework of the Import Substitution Program, the domestic nutrient medium «MHA II-Obolensk» has been successfully developed. The nutrient medium meets the requirements of GOST R ISO 20776-2-2010 «Clinical laboratory testing and in vitro diagnostic test systems - Susceptibility testing of infectious agents and evaluation of performance of antimicrobial susceptibility test devices».
- Molecular mechanisms related to colistin resistance in Enterobacteriaceae. [Journal Article]
- IDInfect Drug Resist 2019; 12:965-975
- Colistin is an effective antibiotic for treatment of most multidrug-resistant Gram-negative bacteria. It is used currently as a last-line drug for infections due to severe Gram-negative bacteria foll…
Colistin is an effective antibiotic for treatment of most multidrug-resistant Gram-negative bacteria. It is used currently as a last-line drug for infections due to severe Gram-negative bacteria followed by an increase in resistance among Gram-negative bacteria. Colistin resistance is considered a serious problem, due to a lack of alternative antibiotics. Some bacteria, including Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacteriaceae members, such as Escherichia coli, Salmonella spp., and Klebsiella spp. have an acquired resistance against colistin. However, other bacteria, including Serratia spp., Proteus spp. and Burkholderia spp. are naturally resistant to this antibiotic. In addition, clinicians should be alert to the possibility of colistin resistance among multidrug-resistant bacteria and development through mutation or adaptation mechanisms. Rapidly emerging bacterial resistance has made it harder for us to rely completely on the discovery of new antibiotics; therefore, we need to have logical approaches to use old antibiotics, such as colistin. This review presents current knowledge about the different mechanisms of colistin resistance.
- Biotemplate of albumen for synthesized iron oxide quantum dots nanoparticles (QDNPs) and investigation of antibacterial effect against pathogenic microbial strains. [Journal Article]
- IJInt J Nanomedicine 2019; 14:3273-3282
- CONCLUSIONS: The present nanobiological samples can be considered as a new material candidate for antibacterial drugs.
- Ultrasound assisted-phytofabricated Fe3O4 NPs with antioxidant properties and antibacterial effects on growth, biofilm formation, and spreading ability of multidrug resistant bacteria. [Journal Article]
- ACArtif Cells Nanomed Biotechnol 2019; 47(1):2405-2423
- Complicated issue in infectious illnesses therapy is increasing of multidrug resistant (MDR) bacteria and biofilms in bacterial infections. In this way, emerging of nanotechnology as a new weapon spe…
Complicated issue in infectious illnesses therapy is increasing of multidrug resistant (MDR) bacteria and biofilms in bacterial infections. In this way, emerging of nanotechnology as a new weapon specifically in the cases of metal nanoparticle (MNPs) synthesis and MNPs surface modification has obtained more attention. In this study, ultrasound-assisted green synthesis method was utilized for the preparation of Fe3O4 NPs with novel shape (dendrimer) through leaf aqueous extract of Artemisia haussknechtii Boiss. Ultraviolet-visible spectroscopy, energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), atomic force microscopic (AFM), X-ray diffraction (XRD) techniques were applied for MNPs physicochemical characterization. Also, disc diffusion assay, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), planktonic and biofilm morphology of three pathogenic bacteria involving Serratia marcescens ATCC 13880, Escherichia coli ATCC 25922, and methicillin-resistant Staphylococcus aureus (MRSA) were evaluated upon treatment of Fe3O4 NPs as antiplanktonic and antibiofilm analysis. Results showed efficient antiplanktonic and antibiofilm activities of biosynthesized Fe3O4 NPs with average diameter size of 83.4 nm. Reduction in biofilm formation of S. aureus ATCC under Fe3O4 NPs stress was significant (66%) in higher MNPs concentration (100 μg/mL). In addition, as first report, spreading ability of S. aureus as important factor in colony expansion on culture medium was reduced by increasing of Fe3O4 NPs. Present study demonstrates striking antiplanktonic, antibiofilm, antispreading mobility and antioxidant aspects of one-pot biosynthesized Fe3O4 NPs with novel shape.
- Disentangling bacterial invasiveness from lethality in an experimental host-pathogen system. [Journal Article]
- MSMol Syst Biol 2019 Jun 11; 15(6):e8707
- Quantifying virulence remains a central problem in human health, pest control, disease ecology, and evolutionary biology. Bacterial virulence is typically quantified by the LT50 (i.e., the time taken…
Quantifying virulence remains a central problem in human health, pest control, disease ecology, and evolutionary biology. Bacterial virulence is typically quantified by the LT50 (i.e., the time taken to kill 50% of infected hosts); however, such an indicator cannot account for the full complexity of the infection process, such as distinguishing between the pathogen's ability to colonize versus kill the hosts. Indeed, the pathogen needs to breach the primary defenses in order to colonize, find a suitable environment to replicate, and finally express the virulence factors that cause disease. Here, we show that two virulence attributes, namely pathogen lethality and invasiveness, can be disentangled from the survival curves of a laboratory population of Caenorhabditis elegans nematodes exposed to three bacterial pathogens: Pseudomonas aeruginosa, Serratia marcescens, and Salmonella enterica We first show that the host population eventually experiences a constant mortality rate, which quantifies the lethality of the pathogen. We then show that the time necessary to reach this constant mortality rate regime depends on the pathogen growth rate and colonization rate, and thus determines the pathogen invasiveness. Our framework reveals that Serratia marcescens is particularly good at the initial colonization of the host, whereas Salmonella enterica is a poor colonizer yet just as lethal once established. Pseudomonas aeruginosa, on the other hand, is both a good colonizer and highly lethal after becoming established. The ability to quantitatively characterize the ability of different pathogens to perform each of these steps has implications for treatment and prevention of disease and for the evolution and ecology of pathogens.
- Cholesterol Degradation and Production of Extracellular Cholesterol Oxidase from Bacillus pumilus W1 and Serratia marcescens W8. [Journal Article]
- BRBiomed Res Int 2019; 2019:1359528
- Cholesterol is a waxy substance present in all types of the body cells. The presence of higher concentration of low density lipoprotein (LDL) is characterized by abnormal cholesterol level and is ass…
Cholesterol is a waxy substance present in all types of the body cells. The presence of higher concentration of low density lipoprotein (LDL) is characterized by abnormal cholesterol level and is associated with cardiovascular diseases which lead to the development of atheroma in arteries known as atherosclerosis. The transformation of cholesterol by bacterial cholesterol oxidase can provide a key solution for the treatment of diseases related to cholesterol and its oxidized derivatives. Previously isolated bacteria from oil-contaminated soil were screened for cholesterol degradation. Among fourteen, five isolates were able to utilize cholesterol. Two strains Serratia marcescens W1 and Bacillus pumilus W8 using cholesterol as only carbon and energy source were selected for degradation studies. Several parameters (incubation time, substrate concentration, pH, temperature, and different metal ions) for cholesterol decomposition by the selected bacterial strains were evaluated. Maximum cholesterol reduction was achieved on the 5th day of incubation, 1g/L of substrate concentration, pH 7, in the presence of Mg2+ and Ca2+ ions, and at 35°C. Cholesterol degradation was analyzed by enzymatic colorimetric method, thin layer chromatography (TLC), and high-performance liquid chromatography (HPLC). Under optimized conditions 50% and 84% cholesterol reduction were recorded with Serratia marcescens W1 and Bacillus pumilus W8, respectively. Cholesterol oxidase activity was assayed qualitatively and quantitatively. The results revealed that Serratia marcescens W1 and Bacillus pumilus W8 have great potential for cholesterol degradation and would be regarded as a source for cholesterol oxidase (CHO).
- Gram-negative Cranial Bone Flap Infection Treated with Continuous Gentamicin Irrigation: A Case Report. [Case Reports]
- CCureus 2019 Mar 20; 11(3):e4282
- A 57-year-old male presented with severely altered mental status in the setting of diabetic ketoacidosis. Neuroimaging revealed two intracranial masses. Days following surgical resection of an olfact…
A 57-year-old male presented with severely altered mental status in the setting of diabetic ketoacidosis. Neuroimaging revealed two intracranial masses. Days following surgical resection of an olfactory groove meningioma, the patient developed Serratia marcescens bacteremia along with an enlarging epidural and subgaleal fluid collection. Subgaleal fluid aspiration was also positive. The patient later returned to the operating room for wound washout where purulent collections were discovered in the subgaleal, epidural, and left subdural spaces. The wound was evacuated and the bone flap was thoroughly cleansed with betadine and soaked in peroxide prior to replacement. Four drains were placed (two subgaleal and two epidural) with two serving as inlets and two as outlets. Continuous irrigation of the subgaleal and epidural spaces with gentamicin solution was performed for five days. The bone flap was successfully salvaged and the patient was discharged from inpatient rehab three weeks following washout.
- Selective antimicrobial effects of curcumin@halloysite nanoformulation: a Caenorhabditis elegans study. [Journal Article]
- AAACS Appl Mater Interfaces 2019 Jun 10
- Alterations in normal gastrointestinal microbial community caused by unhealthy diet, environmental factors and antibiotics overuse may severely affect human health and well-being. Novel antimicrobial…
Alterations in normal gastrointestinal microbial community caused by unhealthy diet, environmental factors and antibiotics overuse may severely affect human health and well-being. Novel antimicrobial drug formulations targeting pathogenic microflora while not affecting or even supporting symbiotic microflora are urgently needed. Here we report fabrication of a novel antimicrobial nanocontainers based on halloysite nanotubes loaded with curcumin and protected with a dextrin outer layer (HNTs+Curc/DX) and its effective use to supress the overgrowth of pathogenic bacteria in Caenorhabditis elegans nematodes. Nanocontainers have been obtained using vacuum-facilitated loading of hydrophobic curcumin into halloysite lumens. We have applied UV-vis and infrared spectroscopy, thermogravimetry and microscopy to characterise the HNTs+Curc/DX nanocontainers. In experiments in vitro we found that HNTs+Curc/DX effectively suppressed the growth of Serratia marcescens cells, while Escherichia coli bacteria were not affected. We applied HNTs+Curc/DX nanocontainers to alleviate the S. marcescens infection in C. elegans nematodes in vivo. The nematodes ingest HNTs+Curc/DX at 4-6 ng per worm, which results in improvement of nematodes' fertility and life expectancy. Remarkably, treatment of S. marcescens-infected nematodes with HNTs+Curc/DX nanocontainers completely restored the longevity, demonstrating the enhanced bioavailability of hydrophobic curcumin. We believe that our results reported here open new avenues for fabrication of effective antimicrobial nanoformulations based on hydrophobic drugs and clay nanotubes.
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- RNA‑seq analyses of antibiotic resistance mechanisms in Serratia marcescens. [Journal Article]
- MMMol Med Rep 2019 May 22
- The present study aimed to further clarify the genetic mechanisms responsible for the antimicrobial resistance of Serratia marcescens (S. marcescens) using RNA sequencing. Three drug‑susceptible S. m…
The present study aimed to further clarify the genetic mechanisms responsible for the antimicrobial resistance of Serratia marcescens (S. marcescens) using RNA sequencing. Three drug‑susceptible S. marcescens strains (named MYQT1, MYQT2, and MYQT3) and three multidrug‑resistant S. marcescens strains (named MYQT4, MYQT5, and MYQT6) were isolated from six different patients and subjected to RNA sequencing. Differentially expressed genes (DEGs) between the multidrug‑resistant S. marcescens strains and drug‑susceptible strains were screened and compared, followed by functional enrichment analysis. In addition, a protein‑protein interaction (PPI) network was constructed, and significant modules were extracted from it. Genes enriched in the significant modules were subjected to further enrichment analysis. MYQT3 had very a different expression pattern from MYQT1 and MYQT2, and thus, MYQT3 was excluded from the following analysis. A total of 225 DEGs were identified, of which SMDB11_RS09300 (GTP cyclohydrolase FolE2) was the most significantly upregulated with a log2 FC of 6.4; these DEGs were enriched in different GO terms, including hydrogen sulfide biosynthetic process, sulfur compound transmembrane transporter activity, and ABC transporter complex. Additionally, several genes were identified to be important genes in the PPI network, including SMDB11_RS17755 (upregulated; glutamate synthase large subunit), SMDB11_RS00590 (upregulated; sulfite reductase subunit α), and SMDB11_RS04505 (upregulated; cystathionine β‑synthase). Thus, SMDB11_RS09300, SMDB11_RS17755, SMDB11_RS00590, and SMDB11_RS04505 may play significant roles in the antimicrobial resistance of S. marcescens by participating in folate metabolism or the integrity of cell membranes. However, further experiments are required to clarify these findings.