Villi Density Research Articles

Experimental study to assess the impact of vasopressors administered during maintenance of the brain-dead donation in the quality of the intestinal graft.

The hemodynamic maintenance of brain-dead donors will influence the quality of the organs procured for transplantation, including the intestine. Although norepinephrine (NE) and dopamine (DA) are commonly used to sustain mean arterial pressure in humans, there are no standardized protocols for their use during maintenance of brain-dead donors. Our aim was to compare the effects of each drug, in the intestinal graft quality using a rat brain-dead donation model. Wistar rats (N = 17) underwent brain death (BD) for 2 hours with NE (NE group) or with DA (DA group) administration; the control group was mechanically ventilated for 2 hours without BD. Jejunum biopsies were obtained at the end of the maintenance period. Histological damage was evaluated using Park-Chiu scale. Villi/crypt ratio, mucosal thickness, Goblet cell count, and villi density were evaluated using ImageJ software (US National Institutes of Health, Bethesda, MD). Barrier damage was assessed by bacterial translocation culture counting on liver samples. The inflammatory status of the intestine was evaluated by CD3+ counting by immunohistochemistry and gene expression analysis of interleukin (IL)-6, IL-22, and CXCL10. Norepinephrine-treated donors had higher focal ischemic injury in the intestinal mucosa without a substantial modification of morphometrical parameters compared with DA-treated donors. CD3+ mucosal infiltration was greater in intestines procured from brain-dead donors, being highest in NE (p ˂ 0.001). Local inflammatory mediators were affected in BD: DA and NE groups showed a trend to lower expression of IL-22, whereas CXCL10 expression was higher in NE versus control group. Brain death promoted intestinal bacterial translocation, but the use of NE resulted in the highest bacterial counting in the liver (p ˂ 0.01). Our results favor the use of DA instead of NE as main vasoactive drug to manage BD-associated hemodynamic instability. Dopamine may contribute to improve the quality of the intestinal graft, by better preserving barrier function and lowering immune cell infiltration.

Abstract P497: Myocardial Infarct Outcome And Weight Gain In Menopause Mice Are Mitigated During Probiotic Oligofructose Treatment

The average woman spends over 40% of their life in menopause, during which estrogen’s protective roles are lost and women suffer an increased risk of developing inflammatory pathologies including obesity and worsened cardiovascular disease outcomes. Yet, safe, and effective menopause therapies are still unavailable. The gut microbiome impacts both metabolic and circulating estrogen homeostasis. A dysbiotic (unhealthy) gut can contribute to pathologies that are also observed during menopause including increased obesity and worsened myocardial infarct (MI) outcomes. We have previously demonstrated that gut manipulation through prebiotics (Oligofructose [OFS]), attenuates myocardial infarct injury, improved glucose tolerance, and reduced weight gain in mice. We hypothesize that loss of estrogen during menopause results in intestine morphological and microbial changes, worsens MI outcomes and increases weight gain, which can be mitigated with OFS treatment. Menopause was induced in female mice fed a high-fat-diet (HFD, 45% fat) via 4-vinylcycohexane diepoxide intraperitoneal injections (controls were injected with sesame oil), menopause (14+days diestrus) was determined by cytology. Following menopause, mice were treated for 6wks with 10% OFS supplemented into the diet (provided ad libitum; controls were fed HFD food only). Mice underwent 3day permanent ligation prior to sacrifice. We observed that menopause results in increased villi density in the duodenum and ileum, and that menopausal mice had a significant increase in both duodenum villi length and wall thickness. Menopause was associated with a shift in the gut microbiota composition. Relative abundance of Alistipes was reduced in menopausal mice, compared to premenopausal mice, and is restored with OFS treatment. Furthermore, menopausal mice had increased weight gain and infarct size compared to premenopausal mice, and OFS attenuated the differences between menopause and perimenopause weight gain over time and infarct size. Together these data demonstrate menopause is associated with intestinal morphological changes and shifts in the gut microbiome, and that in the presence of OFS infarct size and weight gain in menopausal mice are mitigated.

Morphological features of the jejunum and ileum of the middle and heavy goose breeds

We studied the morphological features of the jejunum and ileum in middle and heavy goose breeds. The geese under six month of age of Gorkovskaya and Legart breeds were used in our research. Geese of a heavy breed had a large intestinal mass, length of the jejunum and ileum, thickness of the mucous membrane of the ileum, and a smaller thickness of the muscular tunic of the jejunum. Legart geese had greater villi density and crypt depth in the jejunum and greater height and density of the villi, the width of the crypts, and the ratio of the height of the villi to the depth of the crypts in the ileum. In all the guts of heavier geese, the density of crypts was lower. The geese of the heavy breed had larger number and area of the ganglia of the mental plexus and smaller number and area in the submucosa in the jejunum, while they had larger area of the ganglia of the submucosal plexus in the ileum. The number of argyrophilic and argentaffin apudocytes in the jejunum of geese of different breeds did not differ, when the Legart breed geese had lesser quantity of apudocytes in the ileum.

Dietary glutamine, glutamic acid and nucleotides increase the carbon turnover (δ13C) on the intestinal mucosa of weaned piglets

This study aimed at evaluating the influence of dietary glutamine, glutamic acid and nucleotides on duodenal and jejunal carbon turnover, and on mucosa morphometry of piglets weaned at an age of 21 days. The diets were: additive-free diet – control (C); 1% of glutamine (G); 1% of glutamic acid (GA); and 1% of nucleotides (N). In intestinal mucosa morphometry trial, 65 animals were used. At day 0 (baseline), five animals were slaughtered to determine the villus height (VH), crypt depth (CD), VH : CD ratio and villi density (VD). The remaining 60 animals were allocated into a randomized block design with 4×3 factorial arrangement (four diets: C – control, G – glutamine, GA – glutamic acid and N – nucleotides; three slaughter ages: 7, 14 and 21 days post-weaning) with five piglets slaughtered per treatment. In carbon turnover trial, 123 animals were used. At day 0 (baseline), three animals were slaughtered to quantify the δ13C half-life (T50%) and the 99% carbon substitution (T99%) on intestinal mucosa. The remaining 120 animals were blocked by three weight categories (light, medium and heavy) and, randomly assigned to pen with the same four diets from the previous trial with one piglet slaughtered per weight category per treatment at days 1, 2, 4, 5, 7, 9, 13, 20, 27 and 49 after weaning. Morphometric analyses have yielded no consistent results regarding the action of the evaluated additives, and few reproducible age-related effects. The N diets determined lower T50% values (5.18 days) and T99% (17.21 days) than G and C diets (T50%=7.29, 7.58 days and T99%=24.22, 25.17 days, respectively) in the duodenal mucosa. In jejunum, the N, GA and G diets determined the lowest T50% means (4.9, 6.2 and 6.7 days, respectively) and T99% means (15.34, 21.10 and 21.84 days, respectively) in comparison with C diets (T50%=7.44 and T99%=24.72 days). The inclusion of the additives in the diets of piglets accelerated the carbon turnover in piglets during the post-weaning period. The stable isotopes technique (δ13C) is an important methodology in studies of additives with trophic effects on the intestinal mucosa of the piglets.

Analytical theory of oxygen transport in the human placenta.

We propose an analytical approach to solving the diffusion-convection equations governing oxygen transport in the human placenta. We show that only two geometrical characteristics of a placental cross-section, villi density and the effective villi radius, are needed to predict fetal oxygen uptake. We also identify two combinations of physiological parameters that determine oxygen uptake in a given placenta: (i) the maximal oxygen inflow of a placentone if there were no tissue blocking the flow and (ii) the ratio of transit time of maternal blood through the intervillous space to oxygen extraction time. We derive analytical formulas for fast and simple calculation of oxygen uptake and provide two diagrams of efficiency of oxygen transport in an arbitrary placental cross-section. We finally show that artificial perfusion experiments with no-hemoglobin blood tend to give a two-orders-of-magnitude underestimation of the in vivo oxygen uptake and that the optimal geometry for such setup alters significantly. The theory allows one to adjust the results of artificial placenta perfusion experiments to account for oxygen-hemoglobin dissociation. Combined with image analysis techniques, the presented model can give an easy-to-use tool for prediction of the human placenta efficiency.

The transformation of the utero-placental interface in early pregnancy: Functional insights from computational modeling

The transformation of the utero-placental interface in early pregnancy: Functional insights from computational modeling

A geometrical model for searching an optimal villi density in the inter-villous cross-sections of the human placenta

A geometrical model for searching an optimal villi density in the inter-villous cross-sections of the human placenta

Mesquite bean and cassava leaf in diets for Nile tilapia in growth

This work evaluated the inclusion of mesquite bean bran (Prosopis juliflora) and cassava leaf bran (Manihot esculenta) in diets for Nile tilapia (85.22 ± 3.13 g). Three hundred and thirty-six fish were distributed in 28 fiberglass tanks (120 L) in a 2 × 4 factorial scheme for two sources of oil and four levels of bran (0, 5, 10 and 20%) (n = 4). After 60 days, growth performance (feed intake, weight gain, apparent feed conversion and survival rate) and fish body composition were evaluated. Heights and density of villi were measured for morphometric analysis of the intestinal mucosa. Animal performance, body composition and villi density were not affected (p > 0.05) by the source and level of inclusion of bran. There was a significant effect of the level of inclusion of bran on villi height, with a linear trend, indicating that the higher the inclusion levels of bran, the lower the height of the villi. The bran studied can be used in diets for Nile tilapia up to 20% without compromising growth performance and body composition change, but the presence of these by-products can result in a deleterious effect on fish villi.

Mananoligossacarídeo em dietas para larvas de tilápia

Este experimento foi realizado para avaliar níveis crescentes de mananoligossacarídeo (MOS) na dieta de larvas de tilápias-do-nilo (linhagem Supreme®) na fase de reversão sexual durante 30 dias. Larvas de tilápia-do-nilo (n=1500, P=0,01 g ± 0,001 g) foram distribuídas aleatoriamente em 30 tanques de 100 litros. Os peixes foram distribuídos em delineamento inteiramente casualizado, composto por seis tratamentos e cinco repetições. A dieta controle (isenta de MOS) foi elaborada para conter aproximadamente 35% de proteína bruta e 3.100 kcal de ED/kg. As demais foram suplementadas com 0; 0,15; 0,30; 0,45; 0,60 e 0,75% de MOS em substituição ao milho da dieta controle. Com o aumento nos níveis de MOS nas dietas, foi observado aumento linear sobre o comprimento do intestino, a altura das vilosidades intestinais e a densidade dos vilos. Não houve diferença na composição corporal, no ganho em peso, no peso final, no comprimento final, no fator de condição, na taxa de sobrevivência e no número de células caliciformes do intestino das larvas. Os níveis de MOS tiveram efeito quadrático sobre a conversão alimentar, cujos melhores resultados foram obtidos com 0,34% de MOS. A utilização de MOS no nível de 0,34% em dietas para larvas de tilápia-do-nilo melhora a conversão alimentar e promove aumento do comprimento do intestino, da altura das vilosidades e da densidade de vilos intestinal.

Changes in pig small intestinal absorptive area during the first 14 days of life

The aim of this study was to evaluate the changes in small intestine absorptive area during the first 14 days of life in the pig. The duodenum and mid-jejunum were studied in a total of 16 piglets. Tissue samples were prepared for light microscopy (LM) and scanning electron microscopy (ScEM) at days 0, 3, 7 and 14 of life. The changes in villi density, height and width, crypt depth, mucosa thickness and amount of transversal furrows were used to appraise the surface of absorptive area. According to LM data, villus length and width, crypt depth and mucosa thickness increases from day 0 to day 3, and decreases from day 3 to day 14. ScEM study showed that the villus density reduced from day 0 to day 14 in duodenum, and from day 0 to day 3 in mid-jejunum. The surface of absorptive area was increased almost 3-fold in the duodenum from day 3 to day 7 and more than 2-fold in the jejunum in the same period.

Mananoligossacarídeos e complexo enzimático em dietas para frangos de corte

Avaliou-se o efeito de dietas com mananoligossacarídeos e complexo enzimático (CE) sobre o desempenho, a morfologia intestinal e a qualidade da cama de frangos aos 42 dias de idade. Foram utilizadas 750 aves em delineamento inteiramente casualizado em esquema fatorial 2 × 2 + 1, com dois níveis de mananoligossacarídeos (0 e 0,1% de 1 a 21 dias e 0,05% de 22 a 42 dias de idade), dois níveis de complexo enzimático (0 e 0,05%) e uma dieta com antibióticos (CP), totalizando cinco dietas com cinco repetições. Aos 42 dias de criação, o desempenho foi avaliado e, após o abate das aves, foram coletadas amostras de intestino e de cama e avaliado o desempenho. A inclusão de mananoligossacarídeos e/ou complexo enzimático na dieta não afetou o desempenho das aves, o perímetro e a altura dos vilos duodenais, a profundidade de criptas, a densidade de vilos no duodeno, jejuno e íleo, os teores de matéria seca e nitrogênio total e o pH das camas. A interação mananoligossacarídeos × complexo enzimático foi significativa para perímetro e altura de vilos no jejuno, que foram maiores nas aves alimentadas com as rações sem complexo enzimático e mananoligossacarídeos, mesmo comportamento observado para perímetro e altura de vilos ileais. Entretanto, quando adicionados mananoligossacarídeos e complexo enzimático, os valores dessas variáveis reduziram. A volatilização de amônia aumentou em camas de frango tratados com antibióticos e diminuiu com a adição de mananoligossacarídeos à dieta. A adição de mananoligossacarídeos ou complexo enzimático às dietas aumentou o perímetro e altura de vilos da mucosa do jejuno e do íleo e reduziu a volatilização de amônia da cama.