Effects of a prebiotic formulation on the composition of the faecal microbiota of people with functional constipation

PURPOSE

Prebiotics are defined as substances which selectively promote beneficial gut microbes leading to a health benefit for the host. Limited trials have been carried out investigating their effect on the microbiota composition of individuals afflicted by functional constipation with equivocal outcomes. In a 21-day randomised, controlled clinical trial involving 61 adults with functional constipation, a prebiotic formulation with partially hydrolysed guar gum and acacia gum as its main ingredients, significantly increased complete spontaneous bowel motions in the treatment group. This follow-up exploratory analysis investigated whether the prebiotic was associated with changes to the composition, richness, and diversity of the faecal microbiota.

METHODS

Participants provided a faecal specimen at baseline and on day 21 of the intervention period. Whole genome metagenomic shotgun sequencing comprehensively assessed taxonomic and functional composition of the microbiota.

RESULTS

Linear mixed effects regression models adjusted for potential confounders showed a significant reduction in species richness of 28.15 species (95% CI - 49.86, - 6.43) and Shannon diversity of 0.29 units (95% CI - 0.56, - 0.02) over the trial period in the prebiotic group. These changes were not observed in the control group, and functional composition was unchanged in both groups.

CONCLUSION

In adults with functional constipation, the intake of a prebiotic formulation was associated with a decline of species richness and Shannon diversity. Further research regarding the associations between prebiotics and the composition and function of the gut microbiota is warranted.

Functional constipation and the effect of prebiotics on the gut microbiota: a review

Functional constipation is a significant health issue impacting the lives of an estimated 14 % of the global population. Non-pharmaceutical treatment advice for cases with no underlying medical conditions focuses on exercise, hydration and an increase in dietary fibre intake. An alteration in the composition of the gut microbiota is thought to play a role in constipation. Prebiotics are non-digestible food ingredients that selectively stimulate the growth of a limited number of bacteria in the colon with a benefit for host health. Various types of dietary fibre, though not all, can act as a prebiotic. Short-chain fatty acids produced by these microbes play a critical role as signalling molecules in a range of metabolic and physiological processes including laxation, although details are unclear. Prebiotics have a history of safe use in the food industry spanning several decades and are increasingly used as supplements to alleviate constipation. Most scientific research on the effects of prebiotics and gut microbiota has focussed on inflammatory bowel disease rather than functional constipation. Very few clinical studies evaluated the efficacy of prebiotics in the management of constipation and their effect on the microbiota, with highly variable designs and conflicting results. Despite this, broad health claims are made by manufacturers of prebiotic supplements. This narrative review provides an overview of the literature on the interaction of prebiotics with the gut microbiota and their potential clinical role in the alleviation of functional constipation.

Omega-3 Long-Chain Polyunsaturated Fatty Acids: Are They Beneficial for Physical and Cognitive Functioning in Older Adults?

BACKGROUND

There is equivocal evidence about beneficial properties of omega-3 long-chain polyunsaturated fatty acids (ω-3 LCPUFA) for older adults.

OBJECTIVE

This study investigated the relationship between circulating ω-3 LCPUFA, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels and their corresponding dietary intakes with cognition and physical function in a cohort of community-dwelling older adults at risk of dementia.

METHODS

A cross-sectional analysis was conducted among 142 community-dwelling older adults (60-85 years) with subjective memory complaints. Erythrocyte fatty acids (ω-3 LCPUFA) and the omega-3 index were measured; dietary DHA and EPA were assessed with a LCPUFA specific questionnaire. Cognition was measured using the Cogstate computerised battery and Trail-making tests. Muscle strength was assessed by grip strength and physical function via the four-square step test, 30-second sit-to-stand, timed up-and-go test, and 4-m walk test. Multiple regression analysis was used to assess the relationship between erythrocyte ω-3 LCPUFA, dietary intake, cognitive and physical function.

RESULTS

Higher dietary DHA and EPA were associated with better global cognitive function (DHA: β=0.164, p=0.042; EPA: β=0.188, p=0.020). Higher dietary EPA was associated with better attention/psychomotor composite scores (β=0.196, p=0.024), mobility (four-square step test: β=-0.202, p=0.015) and gait speed (4m walk test: β=-0.200, p=0.017). No associations were found between erythrocyte ω-3 LCPUFA and cognitive or functional performance measures.

CONCLUSIONS

In community-dwelling older adults with subjective memory complaints, higher dietary ω-3 LCPUFA intake was associated with better cognitive and physical function, supporting the evidence that ω-3 fatty acids play a role in optimising physical and cognitive health during ageing.

[Early cancer diagnosis through automated cytoanalysis (Fazytan system)]

A prescreening system for the early detection of uterine cancer was developed. For the diagnosis of each input specimen (PAP-stained), a figure of malignancy has to be calculated automatically. Methods, problems and results of the system are summarized in this paper. Some thousand microscopic subfields of a specimen are successively scanned by an optimized TV-camera with high spatial resolution. The automated specimen analysis can be described by a two step procedure: single cell classification and evaluation of cell population. For the single cell classifier only features derived from the nucleus are used. The pattern recognition procedures are based on a processor-oriented strategy, and can be adapted to other cytological specimen. The algorithms have been tested with 3 . 10(5) cell images of about 300 specimens.

FAZYTAN: a system for fast automated cell segmentation, cell image analysis and feature extraction based on TV-image pickup and parallel processing

Cell location, segmentation and feature extraction of cell images are principal tasks of a high-resolution system for automated cytology. To perform these tasks with high speed, image processing algorithms and the architecture of a processor have to be optimized mutually. This has led to the development of a fast system for the evaluation of cytologic samples based on an optimized TV microscope, a host minicomputer with different peripheral array processors and digital image storages. The processors are optimized in speed for two-dimensional local operations to investigate neighborhood relations and morphology in cell images. Two-dimensional transformations of TV images (288 x 512 x 8 bit) can be carried out within 20 to 200 msec. The processors are able to realize linear filter functions (correlation, convolution) as well as nonlinear functions (median filtering). A set of measurements like area, circumference and connectivity can be derived parallely from one image in 20 msec. The system performs efficient and fast detection and segmentation of cells scanned in one TV frame within one second as well as the extraction of a large number of morphologic features within a few seconds. Based on these procedures, high-resolution analysis of several thousand cells of a sample within one minute will be possible.

Structure analysis and classification of cervical cells using a processing system based on TV

This paper presents preliminary results of a cell classification experiment using a new approach for feature extraction. The algorithm takes into account the special requirements of a fast parallel processing system (processor-oriented algorithms). A cell image is described by several hundred features derived from the nucleus only. The most significant features with respect to classification are determined by statistical analysis. Applying principal axis transform, a new feature set is computed, reduced considerably in dimensions. The data base (1,925 cell images of Papanicolaou-stained cervical specimens) was divided into a training set (963 images) and a test set (962 images). The classification results of the test set show that the recognition rate for the two-class problem (normal, suspicious) is better than 91%, using only ten morphologic features.

Fast and economic conversion of images to a tactile presentation for blind people

A new procedure for the conversion of binary black and white images to a tactile presentation perceptible by the blind is described. Conventional procedures are very time-consuming and expensive and are not adapted to produce the required low editions of tactile displays, e.g., for schools for the blind or individual applications. The procedure recently developed allows the fast, economical conversion of even single drawings to a tactile display with high resolution. An account of the investigations and valuations of all possible physical procedures of optical-to-tactile conversion is given. The new procedure, based on a slightly modified Xerox copying process in a first step and gumming tactile material with the tone powder at the darkened regions in a second step, is described in detail. The device realised is presented. It allows the conversion of one page of a drawing to a tactile display with a resolution of 0.3 mm within 1 min. Various applications of the system and experiences with blind users are reported. The implement proved to meet most of the requirements of blind people. It is easy to handle and produces tactile drawings of excellent quality. As it is based on commercial subsystems it promises an economical production even at small series.

[Cerebro-organic syndrome during gold therapy. Possible correlation between gold therapy in chronic seronegative polyarthritis and the appearance of a cerebro-organic syndrome. A case contribution]

In this article the possible relationship between gold therapy of a chronic seronegative polyarthritis and the appearance of a cerebro-organic syndrome in a 56-year-old postmenopausal woman will be discussed. We take into consideration the basic illness, the biography, the hormonal situation, the simultaneous chloroquin therapy and the overdosage of the gold drug. After a careful consideration of the different diagnostical possibilities following the above mentioned factors, not only a temporal but also a causative relationship of gold therapy and cerebro-organic syndrome seems to be possible.

[A case of Poland syndrome]

A typical case of Poland syndrome is reported; brachiothoracic hemi-aplasia with absence of major pectoralis muscle, shortening of the arm and symbrachydactylia. Additionally, there was some evidence of debility. There were no malformations in the family history.