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Current Issues in Molecular Biology 2020The microbial community inhabiting our intestine, known as 'microbiota', and the ensemble of their genomes (microbiome) regulate important functions of the host, being... (Review)
Review
The microbial community inhabiting our intestine, known as 'microbiota', and the ensemble of their genomes (microbiome) regulate important functions of the host, being essential for health maintenance. The recent development of next-generation sequencing (NGS) methods has greatly facilitated the study of the microbiota and has contributed to evidence of the strong influence exerted by age and diet. However, the precise way in which the diet and its components modify the functionality of the intestinal microbiome is far from being completely known. Changes in the intestinal microbiota occur during ageing, frequently accompanied by physiological changes of the digestive tract, modification of dietary patterns and impairment of the immune system. Establishing nutritional strategies aiming to counterbalance the specific alterations taking place in the microbiota during ageing would contribute to improved health status in the elderly. This review will analyse changes appearing in the intestinal microbiota from adulthood to old age and their association with dietary patterns and lifestyle factors.
Topics: Adult; Aged; Aging; Bacterial Infections; Diet; Gas Chromatography-Mass Spectrometry; Gastrointestinal Microbiome; Gene Expression Profiling; High-Throughput Nucleotide Sequencing; Humans; Inflammation; Metabolomics; Microbiota
PubMed: 31558686
DOI: 10.21775/cimb.036.033 -
Theranostics 2019: Colorectal cancer (CRC) is a malignant tumor with the third highest morbidity rate among all cancers. Driven by the host's genetic makeup and environmental exposures,...
: Colorectal cancer (CRC) is a malignant tumor with the third highest morbidity rate among all cancers. Driven by the host's genetic makeup and environmental exposures, the gut microbiome and its metabolites have been implicated as the causes and regulators of CRC pathogenesis. We assessed human fecal samples as noninvasive and unbiased surrogates to catalog the gut microbiota and metabolome in patients with CRC. : Fecal samples collected from CRC patients (CRC group, n = 50) and healthy volunteers (H group, n = 50) were subjected to microbiome (16S rRNA gene sequencing) and metabolome (gas chromatography-mass spectrometry, GC-MS) analyses. The datasets were analyzed individually and integrated for combined analysis using various bioinformatics approaches. : Fecal metabolomic analysis led to the identification of 164 metabolites spread across 40 metabolic pathways in both groups. In addition, there were 42 and 17 metabolites specific to the H and CRC groups, respectively. Sequencing of microbial diversity revealed 1084 operational taxonomic units (OTUs) across the two groups, and there was less species diversity in the CRC group than in the H group. Seventy-six discriminatory OTUs were identified for the microbiota of H volunteers and CRC patients. Integrated analysis correlated CRC-associated microbes with metabolites, such as polyamines (cadaverine and putrescine). : Our results provide substantial evidence of a novel interplay between the gut microbiome and metabolome (i.e., polyamines), which is drastically perturbed in CRC. Microbe-associated metabolites can be used as diagnostic biomarkers in therapeutic explorations.
Topics: Adult; Aged; Aged, 80 and over; Colorectal Neoplasms; Computational Biology; Feces; Female; Gas Chromatography-Mass Spectrometry; Gastrointestinal Microbiome; Humans; Male; Metabolome; Metabolomics; Microbiota; Middle Aged; RNA, Ribosomal, 16S
PubMed: 31281534
DOI: 10.7150/thno.35186 -
CMAJ : Canadian Medical Association... Dec 1988Complaints related to gastrointestinal gas are commonly encountered in clinical practice. Various therapies have been proposed, yet none has appeared to be extremely... (Review)
Review
Complaints related to gastrointestinal gas are commonly encountered in clinical practice. Various therapies have been proposed, yet none has appeared to be extremely effective. A review of the literature revealed little hard evidence to support the use of simethicone, pancreatic enzymes, anticholinergic agents or antibiotics. Evidence supporting the use of prokinetic agents has been the strongest, and there may be a pathophysiologic basis for the use of these agents if the complaints are related to abnormal intestinal motility. The use of activated charcoal for adsorbing intestinal gas has been effective in healthy subjects but has not been properly investigated in patients with gas complaints. Dietary modification may be beneficial in certain cases. Additional controlled trials are necessary to clarify the issues in the treatment of this common problem.
Topics: Diet; Eructation; Flatulence; Gases; Humans; Intestines
PubMed: 3058280
DOI: No ID Found -
Japanese Journal of Infectious Diseases May 2020Clostridium species are gram-positive, spore-forming, anaerobic rods normally found in the soil and gastrointestinal tract of humans and animals. Spontaneous sepsis due... (Review)
Review
Clostridium species are gram-positive, spore-forming, anaerobic rods normally found in the soil and gastrointestinal tract of humans and animals. Spontaneous sepsis due to C. perfringens is not caused by injury, which sets it apart from the classical gas gangrene that typically follows trauma. Spontaneous C. perfringens sepsis often develops as a rapidly progressive intravascular hemolysis and metabolic acidosis, with high mortality rates of over 70% with standard intensive care. In such cases, alpha toxin secreted by C. perfringens is considered the main toxin responsible for intravascular hemolysis, disseminated intravascular coagulopathy, and multiple organ failure. Theta-toxin causes a cytokine cascade, which results in peripheral vasodilation similar to that seen in septic shock. For C. perfringens infections, antibiotics, such as high-dose penicillin, and surgical drainage as early as possible are the principal treatments of choice. However, considering the current mortality rate of sepsis, outcomes have not improved with the current standard treatment for C. perfringens infections. Monoclonal antibody against theta toxin in combination with gas gangrene antitoxin presents a promising therapeutic option.
Topics: Anti-Bacterial Agents; Antitoxins; Clostridium Infections; Humans; Sepsis
PubMed: 31875607
DOI: 10.7883/yoken.JJID.2019.382 -
Alimentary Pharmacology & Therapeutics Nov 2022Accurate definition of the gastroduodenal and ileocaecal junctions (GDJ, ICJ) is essential for the measurement of regional transit times.
BACKGROUND
Accurate definition of the gastroduodenal and ileocaecal junctions (GDJ, ICJ) is essential for the measurement of regional transit times.
AIMS
To compare the assessment of these landmarks using the novel gas-sensing capsule and validated wireless motility capsule (WMC), and to evaluate intra-subject variance in transit times METHODS: Healthy subjects ingested the gas-sensing capsule and WMC tandemly in random order. Inter-observer agreement was evaluated by intra-class correlation coefficient (ICC). Agreement between the paired devices' transit times was assessed using Bland-Altman analysis; coefficient of variation was performed to express intra-individual variance in transit times. Similar analyses were completed with tandemly ingested gas-sensing capsules.
RESULTS
The inter-observer agreement for landmarks for both capsules was excellent (mean ICC ≥0.97) in 50 studies. The GDJ was identifiable in 92% of the gas-sensing capsule studies versus 82% of the WMC studies (p = 0.27); the ICJ in 96% versus 84%, respectively (p = 0.11). In the primary cohort (n = 26), median regional transit times differed by less than 6 min between paired capsules. Bland-Altman revealed a bias of -0.12 (95% limits of agreement, -0.94 to 0.70) hours for GDJ and - 0.446 (-2.86 to 2.0) hours for ICJ. Similar results were found in a demographically distinct validation cohort (n = 24). For tandemly ingested gas-sensing capsules, coefficients of variation of transit times were 11%-35%, which were similar to variance between the paired gas-sensing capsule and WMC, as were the biases. The capsules were well tolerated.
CONCLUSIONS
Key anatomical landmarks are accurately identified with the gas-sensing capsule in healthy individuals. Intra-individual differences in transit times between capsules are probably due to physiological factors. Studies in populations with gastrointestinal diseases are now required.
Topics: Capsule Endoscopy; Capsules; Gastrointestinal Diseases; Gastrointestinal Motility; Gastrointestinal Transit; Healthy Volunteers; Humans
PubMed: 36082475
DOI: 10.1111/apt.17216