Microorganisms最新文献

Evidence shows that neurodegenerative and neuropsychiatric disorders are influenced by alterations in the gut microbiome. Various diseases have been linked to microbiome dysbiosis, yet there are inconclusive data regarding which microorganisms are associated with each disorder. The aim of our study is to systematically review the recent literature of the past decade to clarify whether the gut microbiome contributes to the understanding of pathogenesis and progression of neurodegenerative disorders. Most included studies showed a strong correlation between the relative abundance of certain microorganisms, mainly species of the phyla Firmicutes and Bacteroidetes, and disorders such as Parkinson's disease (PD) and Alzheimer's disease (AD). It is speculated that the microorganisms and their byproducts have a significant role in brain protein accumulation, neuro-inflammation, and gut permeability. The estimation of microbial populations could potentially improve clinical outcomes and hinder the progression of the disease. However, further research is needed to include more diseases and larger patient samples and identify specific species and subspecies associated with these disorders.

Background: Periprosthetic joint infections (PJIs) are associated with altered coagulation dynamics; therefore, coagulation laboratory studies could be valuable for diagnosing PJI. This study aimed to evaluate the diagnostic role of Rotational Thromboelastometry (ROTEM) in detecting PJIs caused by low-virulence pathogens.

Methods: A retrospective study was conducted, enrolling 78 patients who underwent exchange arthroplasty due to PJI due to high-virulence pathogens (Group A, n = 16), low-virulence pathogens (Group B, n = 20), or due to aseptic loosening (Group C, n = 20). Preoperative laboratory findings were compared among the three groups.

Results: Several ROTEM parameters differed in patients with PJIs caused by low-virulence pathogens, indicating a link between these infections and hypercoagulability. The development of low-virulence PJIs was associated with a higher maximum clot firmness (MCF) (Odds Ratio, 1.12; 95% Confidence Interval, 1.04-1.21; p = 0.001). Additionally, EXTEM MCF was found to have the highest diagnostic accuracy for these infections (Area Under the Curve, 0.841; sensitivity 90.0%; specificity 90.4%), surpassing that of C-reactive protein and the Erythrocyte Sedimentation Rate (p = 0.006 and p = 0.019, respectively).

Conclusions: Our findings suggest that ROTEM analysis is a promising method for detecting the altered hemostatic dynamics associated with PJI caused by low-virulence pathogens.

Quaternary ammonium compounds (QACs) are active ingredients in hundreds of disinfectants for controlling the epidemic of infectious diseases like SARS-CoV-2 (COVID-19), and are also widely used in shale gas exploitation. The occurrence of QAC-resistant bacteria in the environment could enlarge the risk of sterilization failure, which is not fully understood. In this study, QAC-resistant bacteria were enumerated and characterized in 25 soils collected from shale gas exploitation areas. Total counts of QAC-resistant bacteria ranged from 6.81 × 10³ to 4.48 × 10⁵ cfu/g, accounting for 1.59% to 29.13% of the total bacteria. In total, 29 strains were further purified and identified as Lysinibacillus, Bacillus, and Klebsiella genus. There, bacteria covering many pathogenic bacteria showed different QACs tolerance with MIC (minimum inhibition concentration) varying from 4 mg/L to 64 mg/L and almost 58.6% of isolates have not previously been found to tolerate QACs. Meanwhile, the QAC-resistant strains in the produced water of shale gas were also identified. Phylogenetic trees showed that the resistant species in soil and produced water are distinctly different. That is the first time the distribution and characterization of QAC-resistant bacteria in the soil environment has been analyzed.

Stroke represents a significant global health burden, with a substantial impact on mortality, morbidity, and long-term disability. The examination of stroke biomarkers, particularly the oral microbiome, offers a promising avenue for advancing our understanding of the factors that contribute to stroke risk and for developing strategies to mitigate that risk. This review highlights the significant correlations between oral diseases, such as periodontitis and caries, and the onset of stroke. Periodontal pathogens within the oral microbiome have been identified as a contributing factor in the exacerbation of risk factors for stroke, including obesity, dyslipidemia, atherosclerosis, hypertension, and endothelial dysfunction. The alteration of the oral microbiome may contribute to these conditions, emphasizing the vital role of oral health in the prevention of cardiovascular disease. The integration of dental and medical health practices represents a promising avenue for enhancing stroke prevention efforts and improving patient outcomes.

We have investigated the changes in the microbial communities on the surface of trout eggs and the skin of adult trout in relation to the presence of Saprolegnia parasitica. This pathogen causes saprolegniosis, a disease responsible for significant losses in salmonid farms and hatcheries. It is known from other disease systems that the host-associated microbiome plays a crucial role in the defence against pathogens, but if the pathogen predominates, this can lead to dysbiosis. However, analyses of the effects of S. parasitica on the diversity, composition, and function of microbial communities on fish skin and eggs are scarce. Thus, we have collected skin swabs from injured and healthy trout (N = 12), which differed in S. parasitica load, from three different fish farms in Croatia (Kostanjevac, Radovan, and Solin), while trout egg samples (N = 12) were infected with S. parasitica in the laboratory. Illumina sequencing of the V4 region of the 16S rRNA marker gene showed that infection with S. parasitica reduced the microbial diversity on the surface of the eggs, as evidenced by decreased Pielou's evenness and Shannon's indices. We further determined whether the bacterial genera with a relative abundance of >5.0% in the egg/skin samples were present at significantly different abundances in relation to the presence of S. parasitica. The results have shown that some genera, such as Pseudomonas and Flavobacterium, decreased significantly in the presence of the pathogen on the egg surface. On the other hand, some bacterial taxa, such as Acinetobacter and Janthinobacterium, as well as Aeromonas, were more abundant on the diseased eggs and the injured trout skin, respectively. Finally, beta diversity analyses (weighted UniFrac, unweighted UniFrac, Bray-Curtis) have shown that the sampling location (i.e., fish farm), along with S. parasitica infection status, also has a significant influence on the microbial communities' composition on the trout skin and eggs, demonstrating the strong influence of the environment on the shaping of the host surface microbiome. Overall, we have shown that the presence of S. parasitica was associated with changes in the diversity and structure of the trout skin/egg microbiome. The results obtained could support the development of new strategies for the management of saprolegniosis in aquaculture.

Toxoplasmosis represents a significant public health and veterinary concern due to its widespread distribution, zoonotic transmission, and potential for severe health impacts in susceptible individuals and animal populations. The ability to design and produce recombinant proteins with precise antigenic properties is fundamental, as they serve as tools for accurate disease detection and effective immunization strategies, contributing to improved healthcare outcomes and disease control. Most commonly, a prokaryotic expression system is employed for the production of both single antigens and multi-epitope chimeric proteins; however, the cloning strategies, bacterial strain, vector, and expression conditions vary. Moreover, literature reports show the use of alternative microbial systems such as yeast or Leishmania tarentolae. This review provides an overview of the methods and strategies employed for the production of recombinant Toxoplasma gondii antigenic proteins for the serological detection of T. gondii infection and vaccine development.

Microscopic examination of acid-fast mycobacterial bacilli (AFB) in sputum smears remains the most economical and readily available method for laboratory diagnosis of pulmonary tuberculosis (TB). However, this conventional approach is low in sensitivity and labor-intensive. An automated microscopy system incorporating artificial intelligence and machine learning for AFB identification was evaluated. The study was conducted at an infectious disease hospital in Jiangsu Province, China, utilizing an intelligent microscope system. A total of 1000 sputum smears were included in the study, with the system capturing digital microscopic images and employing an image recognition model to automatically identify and classify AFBs. Referee technicians served as the gold standard for discrepant results. The automated system demonstrated an overall accuracy of 96.70% (967/1000), sensitivity of 91.94% (194/211), specificity of 97.97% (773/789), and negative predictive value (NPV) of 97.85% (773/790) at a prevalence of 21.1% (211/1000). Incorporating AI and machine learning into an automated microscopy system demonstrated the potential to enhance the sensitivity and efficiency of AFB detection in sputum smears compared to conventional manual microscopy. This approach holds promise for widespread application in TB diagnostics and potentially other fields requiring labor-intensive microscopic examination.

This study aimed to identify contamination sources in raw milk and cheese on small farms in Brazil by isolating Escherichia coli at various stages of milk production and cheese manufacturing. The study targeted EAEC, EIEC, ETEC, EPEC, STEC, and ExPEC pathotypes, characterizing isolates for the presence of virulence genes, phylogroups, antimicrobial susceptibility, and phylogenetic relationships using PFGE and MLST. The presence of antimicrobial resistance genes and serogroups was also determined. Three categories of E. coli were identified: pathogenic, commensal, and ceftriaxone-resistant (ESBL) strains. Pathogenic EPEC, STEC, and ExPEC isolates were detected in milk and cheese samples. Most isolates belonged to phylogroups A and B1 and were resistant to antimicrobials such as nalidixic acid, ampicillin, kanamycin, streptomycin, sulfisoxazole, and tetracycline. Genetic analysis revealed that E. coli with identical virulence genes were present at different stages within the same farm. The most frequently identified serogroup was O18, and MLST identified ST131 associated with pathogenic isolates. The study concluded that E. coli was present at multiple points in milk collection and cheese production, with significant phylogroups and high antimicrobial resistance. These findings highlight the public health risk posed by contamination in raw milk and fresh cheese, emphasizing the need to adopt hygienic practices to control these microorganisms.

Trypanosoma brucei causes African trypanosomiasis in humans. Infection with T. brucei elicits a potent pro-inflammatory immune response within infected human hosts, and this response is thought to at least be partially due to Toll-like receptor (TLR) activation. In response to stimulation by lipopolysaccharide and other pathogen antigens, TLR4 translocates to lipid rafts, which induces the expression of pro-inflammatory genes. However, cholesterol efflux is acknowledged as anti-inflammatory due to promoting lipid raft disruption. In this study, we wanted to assess the impact of T. brucei "ghosts", which are non-viable T. brucei essentially devoid of intracellular contents, in stimulating macrophage TLR4 translocation to lipid rafts, and whether promoting cholesterol efflux in macrophages incubated with T. brucei ghosts attenuates TLR4-target gene expression. When cultured macrophages were exposed to T. brucei ghosts, we observed an increase in lipid raft TLR4 protein content, which suggests certain surface molecules of T. brucei serve as ligands for TLR4. However, pretreating macrophages with cholesterol acceptors before T. brucei ghost exposure decreased lipid raft TLR4 protein content and the expression of pro-inflammatory TLR4-target genes. Taken together, these results imply that macrophage cholesterol efflux weakens pro-inflammatory responses which occur from T. brucei infection via increasing macrophage lipid raft disruption.

Climate change and the scarcity of primary resources are driving the development of new, more renewable and environmentally friendly industrial processes. As part of this green chemistry approach, extremozymes (extreme microbial enzymes) can be used to replace all or part of the chemical synthesis stages of traditional industrial processes. At present, the production of these enzymes is limited by the cellular chassis available. The production of a large number of extremozymes requires extremophilic cellular chassis, which are not available. This is particularly true of halophilic extremozymes. The aim of this review is to present the current potential and challenges associated with the development of a haloarchaea-based cellular chassis. By overcoming the major obstacle of the limited number of genetic tools, it will be possible to propose a robust cellular chassis for the production of functional halophilic enzymes that can participate in the industrial transition of many sectors.