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Advanced Drug Delivery Reviews Aug 2018A respiratory infection caused by antibiotic-resistant bacteria can be life-threatening. In recent years, there has been tremendous effort put towards therapeutic... (Review)
Review
A respiratory infection caused by antibiotic-resistant bacteria can be life-threatening. In recent years, there has been tremendous effort put towards therapeutic application of bacteriophages (phages) as an alternative or supplementary treatment option over conventional antibiotics. Phages are natural parasitic viruses of bacteria that can kill the bacterial host, including antibiotic-resistant bacteria. Inhaled phage therapy involves the development of stable phage formulations suitable for inhalation delivery followed by preclinical and clinical studies for assessment of efficacy, pharmacokinetics and safety. We presented an overview of recent advances in phage formulation for inhalation delivery and their efficacy in acute and chronic rodent respiratory infection models. We have reviewed and presented on the prospects of inhaled phage therapy as a complementary treatment option with current antibiotics and as a preventative means. Inhaled phage therapy has the potential to transform the prevention and treatment of bacterial respiratory infections, including those caused by antibiotic-resistant bacteria.
Topics: Administration, Inhalation; Anti-Bacterial Agents; Bacteria; Bacterial Infections; Bacteriophages; Humans; Lung Diseases; Phage Therapy
PubMed: 30096336
DOI: 10.1016/j.addr.2018.08.001 -
Clinical Microbiology Reviews Dec 2022All modern advances notwithstanding, pneumonia remains a common infection with substantial morbidity and mortality. Understanding of the etiology of pneumonia continues... (Review)
Review
All modern advances notwithstanding, pneumonia remains a common infection with substantial morbidity and mortality. Understanding of the etiology of pneumonia continues to evolve as new techniques enable identification of already known organisms and as new organisms emerge. We now review the etiology of pneumonia (at present often called "community-acquired pneumonia") beginning with classic bacteriologic techniques, which identified Streptococcus pneumoniae as the overwhelmingly common cause, to more modern bacteriologic studies, which emphasize Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, , Pseudomonas, and normal respiratory flora. Urine antigen detection is useful in identifying and pneumococcus. The low yield of bacteria in recent studies is due to the failure to obtain valid sputum samples before antibiotics are administered. The use of high-quality sputum specimens enables identification of recognized ("typical") bacterial pathogens as well as a role for commensal bacteria ("normal respiratory flora"). Nucleic acid amplification technology for viruses has revolutionized diagnosis, showing the importance of viral pneumonia leading to hospitalization with or without coinfecting bacterial organisms. Quantitative PCR study of sputum is in its early stages of application, but regular detection of high counts of bacterial DNA from organisms that are not seen on Gram stain or grown in quantitative culture presents a therapeutic dilemma. This finding may reflect the host microbiome of the respiratory tract, in which case treatment may not need to be given for them. Finally, host transcriptional signatures might enable clinicians to distinguish between viral and bacterial pneumonia, an important practical consideration.
Topics: Adult; Humans; Bacteriology; Pneumonia, Bacterial; Streptococcus pneumoniae; Pneumonia, Viral; Bacteria; Community-Acquired Infections
PubMed: 36165783
DOI: 10.1128/cmr.00015-22 -
Cell Host & Microbe Jan 2016The host gut microbiota varies across species and individuals but is relatively stable over time within an individual. How the host selectively shapes the microbiota is...
The host gut microbiota varies across species and individuals but is relatively stable over time within an individual. How the host selectively shapes the microbiota is largely unclear. Here, we show that fecal microRNA (miRNA)-mediated inter-species gene regulation facilitates host control of the gut microbiota. miRNAs are abundant in mouse and human fecal samples and present within extracellular vesicles. Cell-specific loss of the miRNA-processing enzyme, Dicer, identified intestinal epithelial cells (IEC) and Hopx-positive cells as predominant fecal miRNA sources. These miRNAs can enter bacteria, such as F. nucleatum and E. coli, specifically regulate bacterial gene transcripts, and affect bacterial growth. IEC-miRNA-deficient (Dicer1(ΔIEC)) mice exhibit uncontrolled gut microbiota and exacerbated colitis, and WT fecal miRNA transplantation restores fecal microbes and ameliorates colitis. These findings identify both a physiologic role by which fecal miRNA shapes the gut microbiota and a potential strategy for manipulating the microbiome.
Topics: Animals; Bacteria; Feces; Gastrointestinal Microbiome; Gastrointestinal Tract; Humans; Mice; MicroRNAs
PubMed: 26764595
DOI: 10.1016/j.chom.2015.12.005 -
PloS One 2018Probiotics are live microorganisms which confer health benefits to the host, and may be isolated from several sources, such as vegetable foodstuffs. Sauerkraut is a...
Probiotics are live microorganisms which confer health benefits to the host, and may be isolated from several sources, such as vegetable foodstuffs. Sauerkraut is a cabbage product resulting from fermentation by a lactic acid bacteria microbial succession, and is a potential source for probiotics. The aim of the present study was the isolation and characterization of probiotic microorganisms from sauerkraut fermentations. Four distinct fermentations were performed, from which lactic acid bacteria were recovered. Overall, 114 isolates were obtained, phenotypically and genotypically characterized, identified to the genus level and evaluated regarding safety and probiotic potential. Representative bacteria were selected for further analysis, 52% being Lactobacillus spp. and 33% belonging to Leuconostoc spp. genus. One isolate revealed to be β-hemolytic, 42% possessed potentially mobile antimicrobial resistance, 88% were resistant to bile and 20% to low pH. The six most promising candidates were further characterized and presented antimicrobial activity against Listeria monocytogenes, three being resistant to lower pH values. Thus, global analysis of data gathered during this study highlighted the identification of three Lactobacillus strains with putative probiotic potential, suggesting the applicability of sauerkraut fermentations as a source for probiotic isolation. Due to their origin these strains should be suited for future application in the food industry, namely vegetable products such as sauerkraut itself.
Topics: Brassica; Cluster Analysis; Colony Count, Microbial; Fermentation; Food Microbiology; Food-Processing Industry; Lactobacillales; Lactobacillus; Leuconostoc; Polymerase Chain Reaction; Probiotics; Species Specificity
PubMed: 30192827
DOI: 10.1371/journal.pone.0203501 -
Journal of Nanobiotechnology Dec 2021Antibiotic resistance is spreading rapidly around the world and seriously impeding efforts to control microbial infections. Although nucleic acid testing is widely... (Review)
Review
Antibiotic resistance is spreading rapidly around the world and seriously impeding efforts to control microbial infections. Although nucleic acid testing is widely deployed for the detection of antibiotic resistant bacteria, the current techniques-mainly based on polymerase chain reaction (PCR)-are time-consuming and laborious. There is an urgent need to develop new strategies to control bacterial infections and the spread of antimicrobial resistance (AMR). The CRISPR-Cas system is an adaptive immune system found in many prokaryotes that presents attractive opportunities to target and edit nucleic acids with high precision and reliability. Engineered CRISPR-Cas systems are reported to effectively kill bacteria or even revert bacterial resistance to antibiotics (resensitizing bacterial cells to antibiotics). Strategies for combating antimicrobial resistance using CRISPR (i.e., Cas9, Cas12, Cas13, and Cas14) can be of great significance in detecting bacteria and their resistance to antibiotics. This review discusses the structures, mechanisms, and detection methods of CRISPR-Cas systems and how these systems can be engineered for the rapid and reliable detection of bacteria using various approaches, with a particular focus on nanoparticles. In addition, we summarize the most recent advances in applying the CRISPR-Cas system for virulence modulation of bacterial infections and combating antimicrobial resistance.
Topics: Animals; Bacteria; Bacterial Infections; CRISPR-Cas Systems; Drug Delivery Systems; Drug Resistance, Bacterial; Humans; Mice
PubMed: 34863214
DOI: 10.1186/s12951-021-01132-8 -
Clinical Microbiology and Infection :... Dec 2020Bacterial co-pathogens are commonly identified in viral respiratory infections and are important causes of morbidity and mortality. The prevalence of bacterial infection... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Bacterial co-pathogens are commonly identified in viral respiratory infections and are important causes of morbidity and mortality. The prevalence of bacterial infection in patients infected with SARS-CoV-2 is not well understood.
AIMS
To determine the prevalence of bacterial co-infection (at presentation) and secondary infection (after presentation) in patients with COVID-19.
SOURCES
We performed a systematic search of MEDLINE, OVID Epub and EMBASE databases for English language literature from 2019 to April 16, 2020. Studies were included if they (a) evaluated patients with confirmed COVID-19 and (b) reported the prevalence of acute bacterial infection.
CONTENT
Data were extracted by a single reviewer and cross-checked by a second reviewer. The main outcome was the proportion of COVID-19 patients with an acute bacterial infection. Any bacteria detected from non-respiratory-tract or non-bloodstream sources were excluded. Of 1308 studies screened, 24 were eligible and included in the rapid review representing 3338 patients with COVID-19 evaluated for acute bacterial infection. In the meta-analysis, bacterial co-infection (estimated on presentation) was identified in 3.5% of patients (95%CI 0.4-6.7%) and secondary bacterial infection in 14.3% of patients (95%CI 9.6-18.9%). The overall proportion of COVID-19 patients with bacterial infection was 6.9% (95%CI 4.3-9.5%). Bacterial infection was more common in critically ill patients (8.1%, 95%CI 2.3-13.8%). The majority of patients with COVID-19 received antibiotics (71.9%, 95%CI 56.1 to 87.7%).
IMPLICATIONS
Bacterial co-infection is relatively infrequent in hospitalized patients with COVID-19. The majority of these patients may not require empirical antibacterial treatment.
Topics: Asia; Bacteria; Bacterial Infections; COVID-19; Coinfection; Critical Illness; Data Management; Female; Humans; Male; Pandemics; Prevalence; Respiratory Tract Infections; United States
PubMed: 32711058
DOI: 10.1016/j.cmi.2020.07.016 -
Aging Aug 2021
Topics: Animals; Bacteria; Bone and Bones; DNA Damage; Gastrointestinal Microbiome; Humans; Intestines; Radiation, Ionizing; Radiotherapy
PubMed: 34406126
DOI: 10.18632/aging.203446 -
Archives of Microbiology Jul 2022The influence of microbiota on the human body is currently the subject of many studies. The composition of bacteria colonizing the gastrointestinal tract varies... (Review)
Review
The influence of microbiota on the human body is currently the subject of many studies. The composition of bacteria colonizing the gastrointestinal tract varies depending on genetic make-up, lifestyle, use of antibiotics or the presence of diseases. The diet is also important in the species diversity of the microbiota. This study is an analysis of the relationships between physical activity, diet, and the microbiota of the gastrointestinal tract in athletes. This review shows the differences in the microbial composition in various sports disciplines, the influence of probiotics on the microbiome, the consequence of which may be achieved even better sports results. Physical activity increases the number of bacteria, mainly of the Clostridiales order and the genus: Lactobacillus, Prevotella, Bacteroides, and Veillonella, and their number varies depending on the sports discipline. These bacteria are present in athletes in sports that require a high VO max. The players' diet also influences the composition of the microbiota. A diet rich in dietary fiber increases the amount of Lactobacillus or Bifidobacterium bacteria, probiotic microorganisms, which indicates the need to supplement the diet with probiotic preparations. It is impossible to suggest an unambiguous answer to how the microbiota of the gastrointestinal tract changes in athletes and requires further analyzes.
Topics: Bacteria; Bifidobacterium; Feces; Gastrointestinal Microbiome; Humans; Lactobacillus; Microbiota; Probiotics
PubMed: 35834007
DOI: 10.1007/s00203-022-03111-5 -
Frontiers in Cellular and Infection... 2019Alterations to the gut microbiota have been previously suggested to be tightly linked to chronic systemic inflammation, which is a major contributing factor to...
Alterations to the gut microbiota have been previously suggested to be tightly linked to chronic systemic inflammation, which is a major contributing factor to complications and disease progression in chronic kidney disease (CKD). Nevertheless, the effect of gut dysbiosis on the pathogenesis and/or production of inflammatory factors in CKD has not been extensively studied to date. In the present study, we conducted 16S ribosomal DNA pyrosequencing using fecal microbiota samples and analyzed the production of serum inflammatory factors in 50 patients with CKD and 22 healthy control (HC) subjects. The results revealed that compared to the HC subjects, patients with CKD exhibited a significant reduction in the richness and structure of their fecal microbiota. At the phylum level, compared to the HC group, patients with CKD also presented reduced abundance of Actinobacteria but increased abundance of Verrucomicrobia. Moreover, the genera , and were enriched in the fecal samples of patients with CKD, while and were enriched in those of the HC subjects. The abundance of in the CKD group was significantly lower than that in the HC group (3.08 vs. 0.67%); this decrease in the abundance of , an important probiotic, in patients with CKD is a striking discovery as it has not been previously reported. Finally, we analyzed whether these changes to the fecal microbiota correlated with CKD clinical characteristics and/or the production of known inflammatory factors. Altered levels of the microbiota genera , and were shown to be correlated with CKD disease-severity indicators, including the estimated glomerular filtration rate. Most notably, was significantly negatively correlated with the production of interleukin-10. The results of the present study suggest that microbiota dysbiosis may promote chronic systemic inflammation in CKD. Furthermore, they support that modifying the gut microbiota, especially , may be a promising potential therapeutic strategy to attenuate the progression of, and/or systemic inflammation in, CKD.
Topics: Adult; Aged; Bacteria; Biomarkers; China; Cytokines; DNA, Bacterial; Dysbiosis; Feces; Female; Gastrointestinal Microbiome; Gastrointestinal Tract; Humans; Inflammation; Male; Middle Aged; Probiotics; RNA, Ribosomal, 16S; Renal Insufficiency, Chronic; Verrucomicrobia
PubMed: 31245306
DOI: 10.3389/fcimb.2019.00206 -
Critical Reviews in Microbiology Nov 2016An important current issue of modern molecular medicine and biotechnology is the search for new approaches to early diagnostic assays and adequate therapy of infectious... (Review)
Review
An important current issue of modern molecular medicine and biotechnology is the search for new approaches to early diagnostic assays and adequate therapy of infectious diseases. One of the promising solutions to this problem might be a development of nucleic acid aptamers capable of interacting specifically with bacteria, protozoa, and viruses. Such aptamers can be used for the specific recognition of infectious agents as well as for blocking of their functions. The present review summarizes various modern SELEX techniques used in this field, and of several currently identified aptamers against viral particles and unicellular organisms, and their applications. The prospects of applying nucleic acid aptamers for the development of novel detection systems and antibacterial and antiviral drugs are discussed.
Topics: Animals; Aptamers, Nucleotide; Bacteria; Communicable Diseases; Humans; SELEX Aptamer Technique; Viruses
PubMed: 26258445
DOI: 10.3109/1040841X.2015.1070115