An analysis of dietary fiber and fecal fiber components including pH in rural Africans with colorectal cancer

Prevotella enterotype associates with diets supporting acidic faecal pH and production of propionic acid by microbiota

Metabolism of dietary fibres by colon microbiota plays an important role for human health. Personal data from a nutrition study (57 subjects) were analysed to elucidate quantitative associations between the diet, faecal microbiome, organic acid concentrations and pH. Ratios of the predominant acids acetate, butyrate and propionate ranged from 1:0.67:0.27 to 1:0.17:0.36. Pectin-rich diets resulted in higher faecal acetate concentrations. Negative correlation between faecal pH and BSS was observed. Higher faecal pH and lower acid concentrations were related to the higher abundance of amino acid degrading Clostridium, Odoribacter and Eubacterium coprostanoligenes, which are weak carbohydrate fermenting taxa. Propionic acid correlated especially to high abundance of Prevotella and low abundance of proteobacteria. The acetate to propionate ratio of the Prevotella enterotype was about half of that of the Bacteroides enterotype. Based on the results we suggest the measurement of faecal pH and organic acid composition for research and diagnostic purposes.

Perioperative Factors Affecting the Healing of Rectovaginal Fistula

Rectovaginal fistula is rare, but a severe complication in gynecology, which despite the effort of clinicians is still not treated successfully in many cases. According to statistics, the healing rates of surgery in patients with RVF range from 20 to 100%. The treatment effectiveness depends on the etiology of fistula, the age of the patients, the presence of comorbidities, the type of surgery and many other factors. Considering the low efficiency of treatment and the high risk of recurrence, the question of possible methods to improve the results occurs. In our review, we analyzed both modifiable and non-modifiable factors which may influence the treatment, healing rate and future fate of the patients. Taking into account all analyzed risk factors, including age, comorbidities, smoking status, microbiology, medications, stoma and stool features, we are aware that rectovaginal fistula's treatment must be individualized and holistic. In cases of poorly healing RVF, the drainage of feces, the use of antibiotic prophylaxis or the implementation of estrogen therapy may be useful. Moreover, microbiome research in women with RVF and towards estrogen therapy should be performed in order to create treatment algorithms in women with fistulae. Those interventions, in our opinion, may significantly improve the outcome of the patients.

Validating a semi-quantitative food frequency questionnaire to assess regional diet in a study of cancer in South West Nigeria

PURPOSE

Cancer burden is rising rapidly in Nigeria, the most populous country in sub-Saharan Africa; this trend may in part be attributable to diet. We developed and validated a semi-quantitative food frequency questionnaire (FFQ) to assess regional diet in Nigeria.

METHODS

We recruited 68 adult participants from rural and urban settings in South West Nigeria. We developed an FFQ administered at baseline and assessed its validity using 3 dietary recalls (baseline, 7 days post baseline, 3 months post baseline). We calculated Spearman's rank correlation coefficients and energy-adjusted de-attenuated correlation coefficients for food items and macronutrients. We evaluated cross-classification using quartiles of macronutrient intake.

RESULTS

Energy-adjusted de-attenuated food item correlations between the FFQ and dietary recalls ranged from -0.08 (smoked beef/goat) to 0.73 (fried snacks) for the average intake from the first 2 recalls (2DR) and from -0.05 (smoked beef/goat) to 0.75 (smoked fish) for the average of all 3 recalls (3DR). Macronutrient correlations ranged from 0.15 (fat) to 0.37 (fiber) for the 2DR and from 0.08 (fat) to 0.41 (carbohydrates) for the 3DR. The percent of participants classified in the same quartile ranged from 16.4% (fat) to 32.8% (fiber, protein) for the 2DR and from 25.6% (fat) to 34.9% (carbohydrates) for the 3DR. Agreement improved when including adjacent quartiles, from 65.5% (carbohydrates) to 70.5% (fat, fiber) for the 2DR and from 62.8% (protein) to 76.8% (carbohydrate) for the 3DR.

CONCLUSION

Our semi-quantitative FFQ was reasonably valid for ranking intake of certain foods and macronutrients in adults in South West Nigeria.

Evaluation of graded levels of corn-fermented protein on stool quality, apparent nutrient digestibility, and palatability in healthy adult cats

Dried distillers' grains, coproducts from the ethanol industry, may provide sustainable ingredients for pet food. Due to new post-fermentation separation techniques, corn-fermented protein (CFP) is higher in protein and lower in fiber compared with traditional dried distillers' grains, increasing its appeal for inclusion into pet food. Therefore, the objectives of this study were to determine the effects of increasing levels of CFP on stool quality, apparent total tract digestibility (ATTD), and palatability in adult cats. Four extruded diets were fed to 11 adult cats in an incomplete 4 × 4 replicated Latin square design. The control diet contained 15% soybean meal (0C) and CFP was exchanged for soybean meal at either 5%, 10%, or 15% (5C, 10C, 15C). Cats were fed each dietary treatment for 9-d adaption followed by 5-d total fecal collection. Feces were scored on a 1 to 5 scale, with 1 representing liquid diarrhea and 5 representing hard pellet-like (Carciofi et al., 2008). A fecal score of 3.5 to 4 was considered ideal. Titanium dioxide was added to all diets (0.4%) as a marker to estimate digestibility. Data were analyzed using a mixed model in SAS (version 9.4, SAS Institute, Inc., Cary, NC) with treatment as a fixed effect and cat and period as random effects. Fecal dry matter percent and dry fecal output were greater (P < 0.05) at elevated levels of CFP. Stool scores were maintained (P > 0.05) throughout treatments (average; 4). Dry matter, organic matter, crude protein, and gross energy ATTD decreased when cats were fed 15C. There was no difference in ATTD of fat or total dietary fiber among treatments. For palatability assessment, cats preferred 5C over 0C but had no preference with increased CFP inclusion. These results suggest that CFP is comparable to SBM, but there may be a maximum inclusion level of 10% when fed to cats.

Dietary Intake and Cancer in Sub-Saharan Africa: A Critical Review of Epidemiological Studies

Cancer incidence is rising rapidly in Sub-Saharan Africa (SSA). Dietary intake is an established risk factor for certain cancers but only a few epidemiological studies have been conducted in SSA. This study systematically reviewed and summarized the published literature on this issue and identified gaps that can be addressed in future research. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and literature searched was conducted until 11/2/2021. Out of the 5,457 potential references, we reviewed 19 eligible studies: 17 case-controls, two cross-sectionals and no cohort study. South Africa and Kenya conducted the majorities of the studies. The commonest studied cancers were esophageal (9/19), colorectal (4/19) and breast (4/19). Only four studies utilized a validated Food Frequency Questionnaire (FFQ). Although most studies (16/19) reported associations between dietary intake and cancer risks, they were lacking important confounders including total energy intake, multivitamin intake, body fat measures, physical-activity, smoking, and alcohol. Despite rapidly expanding cases of cancer associated with diet, the existent evidence on diet-cancer relationship is too scarce to deduce solid conclusions. There is a need for large cohorts with comprehensive datasets, validated dietary instruments while using advanced statistical analyses that can provide further insights into the imperative links between African diet and cancer risk.Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2022.2032217 .

The colorectal cancer-associated faecal microbiome of developing countries resembles that of developed countries

BACKGROUND

The incidence of colorectal cancer (CRC) is increasing in developing countries, yet limited research on the CRC- associated microbiota has been conducted in these areas, in part due to scarce resources, facilities, and the difficulty of fresh or frozen stool storage/transport. Here, we aimed (1) to establish a broad representation of diverse developing countries (Argentina, Chile, India, and Vietnam); (2) to validate a 'resource-light' sample-collection protocol translatable in these settings using guaiac faecal occult blood test (gFOBT) cards stored and, importantly, shipped internationally at room temperature; (3) to perform initial profiling of the collective CRC-associated microbiome of these developing countries; and (4) to compare this quantitatively with established CRC biomarkers from developed countries.

METHODS

We assessed the effect of international storage and transport at room temperature by replicating gFOBT from five UK volunteers, storing two in the UK, and sending replicates to institutes in the four countries. Next, to determine the effect of prolonged UK storage, DNA extraction replicates for a subset of samples were performed up to 252 days apart. To profile the CRC-associated microbiome of developing countries, gFOBT were collected from 41 treatment-naïve CRC patients and 40 non-CRC controls from across the four institutes, and V4 16S rRNA gene sequencing was performed. Finally, we constructed a random forest (RF) model that was trained and tested against existing datasets from developed countries.

RESULTS

The microbiome was stably assayed when samples were stored/transported at room temperature and after prolonged UK storage. Large-scale microbiome structure was separated by country and continent, with a smaller effect from CRC. Importantly, the RF model performed similarly to models trained using external datasets and identified similar taxa of importance (Parvimonas, Peptostreptococcus, Fusobacterium, Alistipes, and Escherichia).

CONCLUSIONS

This study demonstrates that gFOBT, stored and transported at room temperature, represents a suitable method of faecal sample collection for amplicon-based microbiome biomarkers in developing countries and suggests a CRC-faecal microbiome association that is consistent between developed and developing countries.

Patterns of Early-Onset Colorectal Cancer Among Nigerians and African Americans

PURPOSE

Colorectal cancer (CRC) incidence rates are increasing among individuals < 50 years of age (early-onset CRC) globally with causes unknown. Racial/ethnic disparities in early-onset CRC have also grown more pronounced, because Black individuals have higher early-onset CRC incidence and poorer survival compared with White individuals. We describe the prevalence and burden of early-onset CRC among Africans in Nigeria and African Americans (AAs) in the United States.

PATIENTS AND METHODS

We identified Black individuals diagnosed with a first primary CRC ages 18 to 49 years between 1989 and 2017 at Ahmadu Bello University Teaching Hospital in Zaria, Nigeria (Nigerians), and in the United States (AAs) using the National Institutes of Health/National Cancer Institute's SEER program of cancer registries. Multivariable logistic regression models were used to investigate clinical and demographic differences between Nigerians and AAs with early-onset CRC, adjusted for age, sex, tumor site, and histology.

RESULTS

A total of 5,019 Black individuals were diagnosed with early-onset CRC over the study period (379 Nigerians; 4,640 AAs). Overall, approximately one third of young Black patients were diagnosed with rectal tumors (35.8%). Nigerian individuals with early-onset CRC were eight-fold more likely to be diagnosed with rectal tumors (odds ratio [OR], 8.14; 95% CI, 6.23 to 10.62; P < .0001) and more likely to be diagnosed at younger ages (OR, 0.87; 95% CI, 0.86 to 0.89; P < .0001) compared with young African Americans in adjusted models.

CONCLUSION

Compared with AA individuals diagnosed with early-onset CRC, Nigerian individuals harbor distinct features of early-onset CRC. Additional investigation of the histopathologic and biologic heterogeneity of early-onset CRCs among Black individuals is critical for understanding racial disparities in susceptibility and outcomes, which may have implications for tailored early-onset CRC prevention, detection, and treatment strategies.