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BMC Microbiology Nov 2021Although recent studies have indicated that imbalance in the respiratory microbiome composition is linked to several chronic respiratory diseases, the association... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Although recent studies have indicated that imbalance in the respiratory microbiome composition is linked to several chronic respiratory diseases, the association between the lung microbiome and lung cancer has not been extensively studied. Conflicting reports of individual studies on respiratory microbiome alterations in lung cancer complicate the matter for specifying how the lung microbiome is linked to lung cancer. Consequently, as the first meta-analysis on this topic, we integrate publicly available 16S rRNA gene sequence data on lung tissue samples of lung cancer patients to identify bacterial taxa which differ consistently between case and control groups.
RESULTS
The findings of the current study suggest that the relative abundance of several bacterial taxa including Actinobacteria phylum, Corynebacteriaceae and Halomonadaceae families, and Corynebacterium, Lachnoanaerobaculum, and Halomonas genera is significantly decreased (p < 0.05) in lung tumor tissues of lung cancer patients in comparison with tumor-adjacent normal tissues.
CONCLUSIONS
Despite the underlying need for scrutinizing the findings further, the present study lays the groundwork for future research and adds to our limited understanding of the key role of the lung microbiome and its complex interaction with lung cancer. More data on demographic factors and tumor tissue types would help establish a greater degree of accuracy in characterizing the lung microbial community which accords with subtypes and stages of the disease and fully capturing the changes of the lung microbiome in lung cancer.
Topics: Adult; Aged; Aged, 80 and over; Bacteria; DNA, Bacterial; Female; Humans; Lung; Lung Neoplasms; Male; Microbiota; RNA, Ribosomal, 16S
PubMed: 34763672
DOI: 10.1186/s12866-021-02375-z -
Parasite (Paris, France) 2019Blastocystis sp., a unicellular intestinal parasite in humans and animals worldwide, is frequently found in immunocompromized patients and people in close contact with...
Blastocystis sp., a unicellular intestinal parasite in humans and animals worldwide, is frequently found in immunocompromized patients and people in close contact with animals. Here, we reviewed recent studies on the prevalence, subtypes, and distribution of Blastocystis infection in humans and animals in China. To date, more than 12 provinces have reported Blastocystis infection in humans, with identification of six different subtypes (ST1, ST2, ST3, ST4, ST5, and ST6). The overall infection rate reported was 3.37% (3625/107,695), with the lowest prevalence (0.80%) in Fujian province and the highest prevalence (100%) in Guangdong province. ST3 (62%, 186/300) was the most dominant subtype, identified in all tested provinces in China. A total of eight provinces have reported Blastocystis infection in various animals, with the overall prevalence being 24.66% (1202/4874). Molecular analysis revealed 14 subtypes that infected animals, including 10 known (ST1, ST2, ST3, ST4, ST5, ST6, ST7, ST10, ST13, ST14), and 4 novel (Novel1, Novel2, Novel3, Novel4) subtypes. ST5 was the dominant subtype infecting artiodactyls (44.1%, 460/1044), while ST1 commonly infected carnivores (45.5%, 5/11). These findings provide insights into the epidemiological behavior of Blastocystis sp. in China, and could help in developing effective control strategies against the parasite.
Topics: Animals; Blastocystis; Blastocystis Infections; China; DNA, Protozoan; DNA, Ribosomal; Feces; Genetic Variation; Humans; Intestinal Diseases, Parasitic; Phylogeny; Prevalence
PubMed: 31309925
DOI: 10.1051/parasite/2019042 -
European Journal of Medical Research Jun 2024The use of probiotics could promote the balance of the subgingival microbiota to contribute to periodontal health. This study aimed to identify the potential of bacteria...
OBJECTIVES
The use of probiotics could promote the balance of the subgingival microbiota to contribute to periodontal health. This study aimed to identify the potential of bacteria commonly associated with healthy periodontal tissues as probiotic candidates.
MATERIAL AND METHODS
A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed, Scopus, Science Direct, ProQuest, and Ovid databases as well as the combination of Medical Subject Headings (MeSH) and non-MeSH terms. Based on the selection criteria, original studies published in English and identifying the microorganisms present in the periodontium of healthy individuals and patients with periodontitis using the high-throughput 16S ribosomal gene sequencing technique were included.
RESULTS
Out of 659 articles, 12 met the criteria for this review. These articles were published from 2012 to 2020 and mainly originated from the United States, China, and Spain. Most of these studies reported adequate criteria for selecting participants, using standardized clinical criteria, and compliance with quality based on the tools used. In periodontal healthy tissue were identified species like Actinomyces viscosus, Actinomyces naeslundii, Haemophilus parainfluenzae, Rothia dentocariosa, Streptococcus sanguinis, Streptococcus mitis, Streptococcus oralis, Streptococcus gordonii, Streptococcus intermedius, and Prevotella nigrescens which have recognized strains with a capacity to inhibit periodontopathogens.
CONCLUSIONS
S. sanguinis, S. oralis, S. mitis, and S. gordonii are among the bacterial species proposed as potential probiotics because some strains can inhibit periodontopathogens and have been reported as safe for humans.
Topics: Humans; Probiotics; Periodontium; Periodontitis; Bacteria; Microbiota
PubMed: 38877601
DOI: 10.1186/s40001-024-01908-2 -
Annual Review of Biochemistry Jun 2021Codon usage bias, the preference for certain synonymous codons, is found in all genomes. Although synonymous mutations were previously thought to be silent, a large body...
Codon usage bias, the preference for certain synonymous codons, is found in all genomes. Although synonymous mutations were previously thought to be silent, a large body of evidence has demonstrated that codon usage can play major roles in determining gene expression levels and protein structures. Codon usage influences translation elongation speed and regulates translation efficiency and accuracy. Adaptation of codon usage to tRNA expression determines the proteome landscape. In addition, codon usage biases result in nonuniform ribosome decoding rates on mRNAs, which in turn influence the cotranslational protein folding process that is critical for protein function in diverse biological processes. Conserved genome-wide correlations have also been found between codon usage and protein structures. Furthermore, codon usage is a major determinant of mRNA levels through translation-dependent effects on mRNA decay and translation-independent effects on transcriptional and posttranscriptional processes. Here, we discuss the multifaceted roles and mechanisms of codon usage in different gene regulatory processes.
Topics: Animals; Codon Usage; Eukaryota; Gene Expression; Humans; Protein Biosynthesis; Protein Folding; RNA, Messenger; RNA, Transfer; Ribosomes
PubMed: 33441035
DOI: 10.1146/annurev-biochem-071320-112701 -
Health Technology Assessment... May 2015There is growing interest in the potential utility of real-time polymerase chain reaction (PCR) in diagnosing bloodstream infection by detecting pathogen... (Review)
Review
Rapid detection of health-care-associated bloodstream infection in critical care using multipathogen real-time polymerase chain reaction technology: a diagnostic accuracy study and systematic review.
BACKGROUND
There is growing interest in the potential utility of real-time polymerase chain reaction (PCR) in diagnosing bloodstream infection by detecting pathogen deoxyribonucleic acid (DNA) in blood samples within a few hours. SeptiFast (Roche Diagnostics GmBH, Mannheim, Germany) is a multipathogen probe-based system targeting ribosomal DNA sequences of bacteria and fungi. It detects and identifies the commonest pathogens causing bloodstream infection. As background to this study, we report a systematic review of Phase III diagnostic accuracy studies of SeptiFast, which reveals uncertainty about its likely clinical utility based on widespread evidence of deficiencies in study design and reporting with a high risk of bias.
OBJECTIVE
Determine the accuracy of SeptiFast real-time PCR for the detection of health-care-associated bloodstream infection, against standard microbiological culture.
DESIGN
Prospective multicentre Phase III clinical diagnostic accuracy study using the standards for the reporting of diagnostic accuracy studies criteria.
SETTING
Critical care departments within NHS hospitals in the north-west of England.
PARTICIPANTS
Adult patients requiring blood culture (BC) when developing new signs of systemic inflammation.
MAIN OUTCOME MEASURES
SeptiFast real-time PCR results at species/genus level compared with microbiological culture in association with independent adjudication of infection. Metrics of diagnostic accuracy were derived including sensitivity, specificity, likelihood ratios and predictive values, with their 95% confidence intervals (CIs). Latent class analysis was used to explore the diagnostic performance of culture as a reference standard.
RESULTS
Of 1006 new patient episodes of systemic inflammation in 853 patients, 922 (92%) met the inclusion criteria and provided sufficient information for analysis. Index test assay failure occurred on 69 (7%) occasions. Adult patients had been exposed to a median of 8 days (interquartile range 4-16 days) of hospital care, had high levels of organ support activities and recent antibiotic exposure. SeptiFast real-time PCR, when compared with culture-proven bloodstream infection at species/genus level, had better specificity (85.8%, 95% CI 83.3% to 88.1%) than sensitivity (50%, 95% CI 39.1% to 60.8%). When compared with pooled diagnostic metrics derived from our systematic review, our clinical study revealed lower test accuracy of SeptiFast real-time PCR, mainly as a result of low diagnostic sensitivity. There was a low prevalence of BC-proven pathogens in these patients (9.2%, 95% CI 7.4% to 11.2%) such that the post-test probabilities of both a positive (26.3%, 95% CI 19.8% to 33.7%) and a negative SeptiFast test (5.6%, 95% CI 4.1% to 7.4%) indicate the potential limitations of this technology in the diagnosis of bloodstream infection. However, latent class analysis indicates that BC has a low sensitivity, questioning its relevance as a reference test in this setting. Using this analysis approach, the sensitivity of the SeptiFast test was low but also appeared significantly better than BC. Blood samples identified as positive by either culture or SeptiFast real-time PCR were associated with a high probability (> 95%) of infection, indicating higher diagnostic rule-in utility than was apparent using conventional analyses of diagnostic accuracy.
CONCLUSION
SeptiFast real-time PCR on blood samples may have rapid rule-in utility for the diagnosis of health-care-associated bloodstream infection but the lack of sensitivity is a significant limiting factor. Innovations aimed at improved diagnostic sensitivity of real-time PCR in this setting are urgently required. Future work recommendations include technology developments to improve the efficiency of pathogen DNA extraction and the capacity to detect a much broader range of pathogens and drug resistance genes and the application of new statistical approaches able to more reliably assess test performance in situation where the reference standard (e.g. blood culture in the setting of high antimicrobial use) is prone to error.
STUDY REGISTRATION
The systematic review is registered as PROSPERO CRD42011001289.
FUNDING
The National Institute for Health Research Health Technology Assessment programme. Professor Daniel McAuley and Professor Gavin D Perkins contributed to the systematic review through their funded roles as codirectors of the Intensive Care Foundation (UK).
Topics: Bacteremia; Critical Care; Cross Infection; England; False Negative Reactions; False Positive Reactions; Humans; Prospective Studies; Real-Time Polymerase Chain Reaction; Sensitivity and Specificity; State Medicine; Technology Assessment, Biomedical; Time Factors
PubMed: 25961752
DOI: 10.3310/hta19350 -
Nutrients Dec 2019The consortium of trillions of microorganisms that live inside the human gut are integral to health. Little has been done to collate and characterize the microbiome of...
The consortium of trillions of microorganisms that live inside the human gut are integral to health. Little has been done to collate and characterize the microbiome of children. A systematic review was undertaken to address this gap (PROSPERO ID: CRD42018109599). MEDLINE and EMBASE were searched using the keywords: "healthy preadolescent children" and "gut microbiome" to 31 August 2018. Of the 815 journal articles, 42 met the inclusion criteria. The primary outcome was the relative abundance of bacteria at the phylum, family, and genus taxonomic ranks. α-diversity, short chain fatty acid concentrations, diet, sequencing region, and geographical location were documented. The preadolescent gut microbiome is dominated at the phylum level by Firmicutes (weighted overall average relative abundance = 51.1%) and Bacteroidetes (36.0%); genus level by (16.0%), (8.69%), (7.51%), and (5.47%). Geographic location and sequencing region were independently associated with microbial proportions. There was limited consensus between studies that reported α-diversity and short chain fatty acids. Broadly speaking, participants from non-Western locations, who were less likely to follow a Westernized dietary pattern, had higher α-diversity and SCFA concentrations. Confirmatory studies will increase the understanding of the composition and functional capacity of the preadolescent gut microbiome.
Topics: Bacteria; Child; Diet; Gastrointestinal Microbiome; Humans; RNA, Bacterial; RNA, Ribosomal, 16S
PubMed: 31861722
DOI: 10.3390/nu12010016 -
Frontiers in Oncology 2019Recent studies supported the predictive role of ribosomal protein S6 kinase 1 (S6K1), phosphorylated S6K1 (p-S6K1), and phosphorylated ribosomal protein S6 (p-S6) for...
Recent studies supported the predictive role of ribosomal protein S6 kinase 1 (S6K1), phosphorylated S6K1 (p-S6K1), and phosphorylated ribosomal protein S6 (p-S6) for the outcome of cancer patients. However, inconsistent results were acquired across different researches. To comprehensively and quantitatively elucidate their prognostic significance in solid malignancies, the current meta-analysis was carried out utilizing the results of clinical studies. We conducted the literature retrieval by searching PubMed, Web of Science, EMBASE, and Cochrane library to identify eligible publications. Data were collected from included articles to calculate pooled overall survival (OS), disease-free survival (DFS), recurrence-free survival (RFS), and progression-free survival (PFS). Hazard ratios (HRs) with 95% confidence intervals (CIs) served as appropriate parameters to assess prognostic significance. Forty-four original studies were included, of which 7 studies were analyzed for S6K1, 24 for p-S6K1, and 16 for p-S6. The overexpression of p-S6K1 was significantly associated with poorer prognosis of solid tumor patients in OS (HR = 1.706, 95%CI: 1.369-2.125, < 0.001), DFS (HR = 1.665, 95%CI: 1.002-2.768, = 0.049). However, prognostic role of p-S6K1 in RFS and PFS was not found. The result also revealed that S6K1 and p-S6 were significantly associated with reduced OS (HR = 1.691, 95%CI: 1.306-2.189, < 0.001; HR = 2.019, 95%CI: 1.775-2.296, < 0.001, respectively). The present meta-analysis demonstrated that elevated expression of S6K1, p-S6K1, or p-S6 might indicate worse prognosis of patients with solid tumors, and supported a promising clinical test to predict solid tumor prognosis based on the level of S6K1 pathway.
PubMed: 31139572
DOI: 10.3389/fonc.2019.00390 -
BMC Microbiology Nov 2022Dozens of studies have demonstrated gut dysbiosis in COVID-19 patients during the acute and recovery phases. However, a consensus on the specific COVID-19 associated... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Dozens of studies have demonstrated gut dysbiosis in COVID-19 patients during the acute and recovery phases. However, a consensus on the specific COVID-19 associated bacteria is missing. In this study, we performed a meta-analysis to explore whether robust and reproducible alterations in the gut microbiota of COVID-19 patients exist across different populations.
METHODS
A systematic review was conducted for studies published prior to May 2022 in electronic databases. After review, we included 16 studies that comparing the gut microbiota in COVID-19 patients to those of controls. The 16S rRNA sequence data of these studies were then re-analyzed using a standardized workflow and synthesized by meta-analysis.
RESULTS
We found that gut bacterial diversity of COVID-19 patients in both the acute and recovery phases was consistently lower than non-COVID-19 individuals. Microbial differential abundance analysis showed depletion of anti-inflammatory butyrate-producing bacteria and enrichment of taxa with pro-inflammatory properties in COVID-19 patients during the acute phase compared to non-COVID-19 individuals. Analysis of microbial communities showed that the gut microbiota of COVID-19 recovered patients were still in unhealthy ecostates.
CONCLUSIONS
Our results provided a comprehensive synthesis to better understand gut microbial perturbations associated with COVID-19 and identified underlying biomarkers for microbiome-based diagnostics and therapeutics.
Topics: Humans; RNA, Ribosomal, 16S; Gastrointestinal Microbiome; COVID-19; Dysbiosis; Bacteria; Feces
PubMed: 36376804
DOI: 10.1186/s12866-022-02686-9 -
Microbial Genomics Aug 2021Ethnicity is consistently reported as a strong determinant of human gut microbiota. However, the bulk of these studies are from Western countries, where microbiota... (Meta-Analysis)
Meta-Analysis
Ethnicity is consistently reported as a strong determinant of human gut microbiota. However, the bulk of these studies are from Western countries, where microbiota variations are mainly driven by relatively recent migration events. Malaysia is a multicultural society, but differences in gut microbiota persist across ethnicities. We hypothesized that migrant ethnic groups continue to share fundamental gut traits with the population in the country of origin due to shared cultural practices despite subsequent geographical separation. To test this hypothesis, the 16S rRNA gene amplicons from 16 studies comprising three major ethnic groups in Malaysia were analysed, covering 636 Chinese, 248 Indian and 123 Malay individuals from four countries (China, India, Indonesia and Malaysia). A confounder-adjusted permutational multivariate analysis of variance (PERMANOVA) detected a significant association between ethnicity and the gut microbiota (PERMANOVA =0.005, pseudo-=2.643, =0.001). A sparse partial least squares - discriminant analysis model trained using the gut microbiota of individuals from China, India and Indonesia (representation of Chinese, Indian and Malay ethnic group, respectively) showed a better-than-random performance in classifying Malaysian of Chinese descent, although the performance for Indian and Malay were modest (true prediction rate, Chinese=0.60, Indian=0.49, Malay=0.44). Separately, differential abundance analysis singled out as being elevated in Indians. We postulate that despite the strong influence of geographical factors on the gut microbiota, cultural similarity due to a shared ethnic origin drives the presence of a shared gut microbiota composition. The interplay of these factors will likely depend on the circumstances of particular groups of migrants.
Topics: China; Ethnicity; Gastrointestinal Microbiome; High-Throughput Nucleotide Sequencing; Humans; India; Indonesia; Malaysia; RNA, Ribosomal, 16S
PubMed: 34463609
DOI: 10.1099/mgen.0.000619 -
Frontiers in Cellular and Infection... 2020Traditionally recognized as environmental bacteria, Planctomycetes have just been linked recently to human pathology as opportunistic pathogens, arousing a great...
Planctomycetes as Host-Associated Bacteria: A Perspective That Holds Promise for Their Future Isolations, by Mimicking Their Native Environmental Niches in Clinical Microbiology Laboratories.
Traditionally recognized as environmental bacteria, Planctomycetes have just been linked recently to human pathology as opportunistic pathogens, arousing a great interest for clinical microbiologists. However, the lack of appropriate culture media limits our future investigations as no Planctomycetes have ever been isolated from patients' specimens despite several attempts. Several Planctomycetes have no cultivable members and are only recognized by 16S rRNA gene sequence detection and analysis. The cultured representatives are slow-growing fastidious bacteria and mostly difficult to culture on synthetic media. Accordingly, the provision of environmental and nutritional conditions like those existing in the natural habitat where yet uncultured/refractory bacteria can be detected might be an option for their potential isolation. Hence, we systematically reviewed the various natural habitats of Planctomycetes, to review their nutritional requirements, the physicochemical characteristics of their natural ecological niches, current methods of cultivation of the Planctomycetes and gaps, from a perspective of collecting data in order to optimize conditions and the protocols of cultivation of these fastidious bacteria. Planctomycetes are widespread in freshwater, seawater, and terrestrial environments, essentially associated to particles or organisms like macroalgae, marine sponges, and lichens, depending on the species and metabolizable polysaccharides by their sulfatases. Most Planctomycetes grow in nutrient-poor oligotrophic environments with pH ranging from 3.4 to 11, but a few strains can also grow in quite nutrient rich media like M600/M14. Also, a seasonality variation of abundance is observed, and bloom occurs in summer-early autumn, correlating with the strong growth of algae in the marine environments. Most Planctomycetes are mesophilic, but with a few Planctomycetes being thermophilic (50°C to 60°C). Commonly added nutrients are N-acetyl-glucosamine, yeast-extracts, peptone, and some oligo and macro-elements. A biphasic host-associated extract (macroalgae, sponge extract) conjugated with a diluted basal medium should provide favorable results for the success of isolation in pure culture.
Topics: Animals; Bacteria; Humans; Laboratories; Phylogeny; RNA, Ribosomal, 16S; Seawater
PubMed: 33330115
DOI: 10.3389/fcimb.2020.519301