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1.
Food Funct ; 11(1): 768-778, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31917381

RESUMO

Whey protein isolate (WPI) nanoparticles were fabricated with Ca2+ induced cross-linking and used as an effective particle stabilizer for high internal phase Pickering emulsion (HIPPE) formulation aiming to improve the chemical stability and bioaccessibility of ß-carotene (BC). Ca2+ concentration dominated the characteristics of WPI nanoparticles. Spherically shaped and homogeneously dispersed WPI nanoparticles with a Z-average diameter of approximately 150.0 nm were obtained with 5.0 mM Ca2+ concentration. No cytotoxicity was observed for WPI nanoparticles even at 10.0 mg mL-1 concentration. HIPPE (oil fraction 80.0%, w/w) can be successfully prepared with WPI nanoparticles at a concentration as low as 0.2% (w/w) and was stable for at least 2 months at room temperature. A higher WPI nanoparticle concentration resulted in more solid-like HIPPEs. BC exhibited appreciably higher retention in HIPPEs than in bulk oil during 30 days of storage at 50 °C. Moreover, BC bioaccessibility was appreciably improved with the HIPPE delivery system. Both the chemical stability and bioaccessibility of BC increased with the increase of WPI nanoparticle concentrations from 0.2 to 1.0% (w/w). The results obtained in this study may facilitate the fabrication of edible and biocompatible protein-based nanoparticle stabilizers for HIPPE formulation with more innovative and tailored functionalities.


Assuntos
Proteínas do Soro do Leite/química , beta Caroteno/química , Cálcio/química , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Armazenamento de Medicamentos , Emulsões/química , Humanos , Nanopartículas , beta Caroteno/farmacocinética
2.
Am J Physiol Endocrinol Metab ; 318(2): E111-E116, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31794261

RESUMO

Bacteria and mammals exhibit all aspects of symbiosis. Metabolic flux in bacteria and in specific host cells can influence host-microbe symbiotic relationships and tip the balance between mutualism, commensalism, and parasitism. The relationship between microbes and host metabolism is bidirectional: microbes can influence host blood glucose, but glucose levels can influence the microbiota and host response to specific bacteria. A key consideration determining symbiotic relationships is compartmentalization of bacterial niches by mucosal, chemical, and physical barriers of the gut. We propose that compartmentalization of glucose levels in the blood versus the intestinal lumen is another important factor dictating host-microbe symbiosis. Host glucose and specific bacteria can modify the intestinal barrier, immune function, and antimicrobial defenses, which can then break down compartmentalization of microbes, alter glucose levels and impact symbiosis. Determining how glucose metabolism promotes mutualistic, commensal, and parasitic relationships within the entire microbiota community is relevant to glucose control in diabetes and enteric infections, which occur more often and have worse outcomes in diabetics.


Assuntos
Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Glucose/farmacologia , Simbiose , Animais , Humanos
3.
Minerva Gastroenterol Dietol ; 65(3): 229-238, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31617696

RESUMO

Trimebutine maleate has been used extensively, since the late 1960's, for the treatment of functional gastrointestinal disorders, including irritable bowel syndrome (IBS). It is usually linked to the antispasmodic class of agents, but its properties make trimebutine an unmatched and multi-tasking compound. The efficacy on relieving abdominal pain has been demonstrated in various clinical studies with different protocols of treatment. The main effect was first believed to be merely due to its antispastic activity, but further evidences expanded the acknowledgement of a broader impact on the gastrointestinal tract. The actions of trimebutine are mediated via an agonist effect on peripheral mu, kappa and delta opiate receptors and a modulation of gastrointestinal peptides release. The final motor effects on the gut are summarized in an acceleration of the gastric emptying, an induction of premature phase III of the migrating motor complex in the small intestine and a modulation of the contractile activity of the colon. Moreover, it has been shown to have a role in regulating the visceral sensitivity. It has been observed that this drug is also a multiple-ion channel modulator in the gut. Its function at various levels, from motility to pain control, makes this drug unique and its spectrum of action can be exploited for the treatment of both hypermotility and hypomotility disorders including irritable bowel syndrome and other functional gastrointestinal diseases. This article provides an overview of the current knowledge on the pharmacological mechanisms of trimebutine and its clinical applications in gastrointestinal disorders. Its biochemical properties and the complex mechanisms of action, along with a well-studied pharmacological safety, make this compound still actual and valuable.


Assuntos
Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Fármacos Gastrointestinais/farmacologia , Fármacos Gastrointestinais/uso terapêutico , Gastroenteropatias/tratamento farmacológico , Trimebutina/farmacologia , Trimebutina/uso terapêutico , Animais , Humanos , Síndrome do Intestino Irritável/tratamento farmacológico
4.
Nutr Rev ; 76(1): 29-46, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29087531

RESUMO

Berries are generally considered beneficial to health. This health-promoting potential has mainly been ascribed to berries' phytochemical and vitamin content, and little attention has been paid to the potential benefits of berries for the digestive tract, despite this being the first point of contact. In vivo studies that described the health effects of berries on individual parts of the digestive tract (ie, the mouth, esophagus, stomach, small and large intestine, microbiome, and immune system) were reviewed. Immune effects were included because a large part of the immune system is located in the intestine. Beneficial health effects were mainly observed for whole berry extracts, not individual berry components. These effects ranged from support of the immune system and beneficial microbiota to reduction in the number and size of premalignant and malignant lesions. These results demonstrate the potency of berries and suggest berries can serve as a strong adjuvant to established treatments or therapies for a variety of gastrointestinal and immune-related illnesses.


Assuntos
Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Frutas , Sistema Imunitário , Compostos Fitoquímicos , Dieta , Humanos , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/fisiologia
5.
Pestic Biochem Physiol ; 142: 67-76, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29107249

RESUMO

Biotechnological techniques allow the investigation of alternatives to outdated chemical insecticides for crop protection; some investigations have focused on the identification of molecules tailored from nature for this purpose. We, herein, describe the negative effects of water-soluble lectin from Moringa oleifera seeds (WSMoL) on Anagasta kuehniella development. The chitin-binding lectin, WSMoL, impaired the larval weight gain by 50% and affected the activity of the pest's major digestive enzymes. The commitment of the digestive process became evident after controlled digestion studies, where the capacity of protein digestion was compromised by >90%. Upon acute exposure, the lectin was not resistant to digestion; however, chronic ingestion of WSMoL was able to reverse this feature. Thus, we show that resistance to digestion may not be a prerequisite for a lectin's ability to exert negative effects on larval physiology. The mechanism of action of WSMoL involves binding to chitin with possible disruption to the peritrophic membrane, causing disorder between the endo- and ectoperitrophic spaces. Additionally, results suggest that WSMoL may trigger apoptosis in gut cells, leading to the lower enzymatic activity observed in WSMoL-fed larvae. Although assays employing an artificial diet did not demonstrate effects of WSMoL on A. kuehniella mortality, this lectin may hold potential for exerting insecticide effects on other pest insects, as well for use in other experimental approaches, such as WSMoL-expressing plants. Moreover, the use of WSMoL with other biotechnological tools, such as 'pyramid' crops, may represent a strategy for delaying the evolution of pest resistance to transgenic crops, since its multiple site targets could act in synergism with other insecticide compounds.


Assuntos
Inseticidas/farmacologia , Lectinas/farmacologia , Moringa oleifera/química , Mariposas/fisiologia , Animais , Quitina/química , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Inseticidas/química , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Lectinas/química , Mariposas/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Sementes/química
6.
Int J Mol Sci ; 18(8)2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28829377

RESUMO

Cadmium (Cd) is one of the most harmful metals, being toxic to most animal species, including marine invertebrates. Among marine gastropods, the periwinkle (Littorina littorea) in particular can accumulate high amounts of Cd in its midgut gland. In this organ, the metal can elicit extensive cytological and tissue-specific alterations that may reach, depending on the intensity of Cd exposure, from reversible lesions to pathological cellular disruptions. At the same time, Littorina littorea expresses a Cd-specific metallothionein (MT) that, due to its molecular features, expectedly exerts a protective function against the adverse intracellular effects of this metal. The aim of the present study was, therefore, to assess the time course of MT induction in the periwinkle's midgut gland on the one hand, and cellular and tissue-specific alterations in the digestive organ complex (midgut gland and digestive tract) on the other, upon exposure to sub-lethal Cd concentrations (0.25 and 1 mg Cd/L) over 21 days. Depending on the Cd concentrations applied, the beginning of alterations of the assessed parameters followed distinct concentration-dependent and time-dependent patterns, where the timeframe for the onset of the different response reactions became narrower at higher Cd concentrations compared to lower exposure concentrations.


Assuntos
Cádmio/administração & dosagem , Cádmio/toxicidade , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Gastrópodes/efeitos dos fármacos , Gastrópodes/fisiologia , Sequência de Aminoácidos , Animais , Cálcio/metabolismo , Tecido Conjuntivo/efeitos dos fármacos , Tecido Conjuntivo/metabolismo , Tecido Conjuntivo/patologia , Exposição Ambiental , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Metalotioneína/química , Metalotioneína/genética , Metalotioneína/metabolismo , Polimorfismo de Nucleotídeo Único
7.
Poult Sci ; 96(6): 1948-1955, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27920189

RESUMO

This study was conducted to determine the effects of maize naturally contaminated with aflatoxin B1 (AFB1) on growth performance, intestinal morphology, relative digestive organs weight, digestive enzymes activities, and biochemical index of intestinal development in ducks. A total of 640 ducks was blocked on the basis of sex and body weight, and then allocated randomly to 2 treatments with 20 pens per treatment and 16 ducks per pen. The experiment lasted for 5 wk, and dietary treatments included basal diet (CON) and diets with 100% of normal maize replaced by AFB1 contaminated maize. Detectable levels of other toxins were present but only AFB1 exceeded limits and the level of AFB1 was 195.4 ug/kg in the contaminated maize, and ranged from 2.91 to 120.02 ug/kg in the starter diet and 2.03 to 153.12 ug/kg in the grower diet. Feeding AFB1 contaminated diets decreased (P < 0.05) ADG and ADFI during the whole experiment, whereas F/G during d 15 to 35 and d zero to 35 was reduced (P < 0.05). The mortality of ducks fed AFB1 contaminated diets increased (P < 0.05). Ducks fed AFB1 contaminated diets had greater (P < 0.05) relative weights of proventriculus and gizzard on d 14 as well as the duodenum, jejunum, and ileum on d 14 and 35. Feeding AFB1 contaminated diets increased (P < 0.05) crypt depth, villus width, and surface area in the duodenum on d 35 and villus height, villus width, and surface area in the jejunum on d 14. The activities of alkaline phosphatase and leucine aminopeptidase in the jejunum brush border together with chymotrypsin and trypsin in the pancreas increased (P < 0.05) on d 14 with the inclusion of AFB1 contaminated maize. The jejunum villus became long and wide in ducks fed AFB1 contaminated diets. Taken together, the feeding of maize naturally contaminated with AFB1 caused adverse effects on growth performance and intestinal morphology, and altered digestive physiology and development.


Assuntos
Aflatoxina B1/toxicidade , Ração Animal/análise , Patos/metabolismo , Intestinos/efeitos dos fármacos , Zea mays/química , Ração Animal/microbiologia , Animais , Dieta/veterinária , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Patos/crescimento & desenvolvimento , Feminino , Intestinos/enzimologia , Intestinos/patologia , Masculino , Tamanho do Órgão/efeitos dos fármacos , Zea mays/microbiologia
8.
Anim Sci J ; 88(3): 463-467, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27481564

RESUMO

This study aimed to investigate the effects of manganese (Mn) supplementation on nutrient digestibility and antler growth in male sika deer. Twenty 3-year-old male sika deer were divided into four groups (Control, T40, T80 and T120). The control diet contained 22.2 mg Mn/kg. The treatment diets were supplemented with 40, 80 and 120 mg of Mn/kg (provided as Mn methionine). The results showed that the digestibility of dry matter and crude protein in the T80 group was greater than other groups. Higher digestibility of neutral detergent fiber and acid detergent fiber was observed in the T80 group than in the control group. Plasma Mn concentrations in the T80 and T120 groups were higher (P < 0.01) than control and T40 group (P < 0.01). The concentration of Mn in feces was increased with increasing Mn amount. Average daily gain of fresh antler and dry antler of T80 was greater than other groups, especially the control group (P < 0.05). In conclusion, the suitable level of Mn supplementation was found to be 80 mg/kg (total Mn content 103.4 mg/kg dry matter), which significantly increased antler daily gain and feed digestibility in 3-year-old sika deer.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Cervos/crescimento & desenvolvimento , Cervos/fisiologia , Dieta/veterinária , Suplementos Nutricionais , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Manganês/administração & dosagem , Proteólise/efeitos dos fármacos , Animais , Alimentos , Masculino , Manganês/farmacologia
9.
J Anim Sci ; 92(9): 3954-65, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24987065

RESUMO

Two experiments were conducted to determine the effect of increasing dietary CaO on ruminal fermentation, diet digestibility, performance, and carcass characteristics of feedlot steers fed 60% dried distillers grains with solubles ( DDGS: ). In Exp. 1, 120 steers were allotted by weight (355 ± 7.9 kg) to 1 of 4 treatments containing 60% DDGS, 20% corn silage, 13.5 to 14.4% ground corn, 4% supplement, and 0 to 2.5% limestone on DM basis to determine the effects of CaO on performance and carcass characteristics. Treatments consisted of 0, 0.8, 1.6, or 2.4% CaO inclusion in the diet (DM basis), with CaO replacing limestone. Steers were slaughtered at a target BW of approximately 641 kg. In Exp. 2, 4 steers (initial BW = 288 ± 3 kg) were randomly allotted to the same diets in a 4 × 4 Latin square design (14-d periods) to determine the effects of CaO on ruminal pH, VFA, and nutrient digestibility. Statistical analyses were conducted using the MIXED procedure of SAS. Inclusion of CaO at 0.8, 1.6, and 2.4% increased ADG by 5.0, 3.9, and 0%, respectively, compared to 0% CaO (quadratic; P = 0.03). Intake was linearly decreased (P = 0.04) and G:F was linearly increased (P = 0.02) by CaO inclusion. Dressing percentage increased as CaO increased from 0 to 1.6% and then decreased for 2.4% CaO (quadratic; P < 0.01). In Exp. 2, steers fed 0% CaO had the greatest prefeeding ruminal pH, steers fed 0 and 0.8% CaO exhibited the most rapid postfeeding decline in ruminal pH, and steers fed 2.4% CaO exhibited a relatively stable ruminal pH throughout the 24-h period (treatment × time; P ≤ 0.01). Acetate, butyrate, and total VFA concentrations increased linearly (P ≤ 0.05) at 0, 3, 6, and 12 h postfeeding with increasing CaO. Propionate at 3 h postfeeding increased from 0 to 1.6% CaO and decreased from 1.6 to 2.4% CaO (quadratic; P = 0.10). Urine pH increased linearly (P ≤ 0.01) while urine output and urine ammonia decreased linearly (P ≤ 0.05) as CaO inclusion increased. Apparent NDF digestibility tended to increase (P = 0.07) and ADF digestibility did (P = 0.01) increase linearly with increasing concentrations of CaO. In conclusion, CaO improved ruminal pH variation, increased fiber digestibility, and decreased metabolic acid load in cattle fed 60% DDGS-based diets. Inclusion of CaO up to 1.6% was effective in improving performance of feedlot cattle.


Assuntos
Ração Animal/análise , Compostos de Cálcio/farmacologia , Bovinos/metabolismo , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Grão Comestível , Fermentação/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Óxidos/farmacologia , Amônia/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Compostos de Cálcio/análise , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Fibras na Dieta/metabolismo , Concentração de Íons de Hidrogênio , Masculino , Óxidos/análise , Distribuição Aleatória , Rúmen/fisiologia , Zea mays
11.
PLoS One ; 8(9): e74889, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24098675

RESUMO

Jasmonate inducible plant leucine aminopeptidase (LAP) is proposed to serve as direct defense in the insect midgut. However, exact functions of inducible plant LAPs in the insect midgut remain to be estimated. In the present investigation, we report the direct defensive role of pigeon pea inducible LAP in the midgut of Helicoverpa armigera (Lepidoptera: Noctuidae) and responses of midgut soluble aminopeptidases and serine proteinases upon LAP ingestion. Larval growth and survival was significantly reduced on the diets supplemented with pigeon pea LAP. Aminopeptidase activities in larvae remain unaltered in presence or absence of inducible LAP in the diet. On the contrary, serine proteinase activities were significantly decreased in the larvae reared on pigeon pea LAP containing diet as compared to larvae fed on diet without LAP. Our data suggest that pigeon pea inducible LAP is responsible for the degradation of midgut serine proteinases upon ingestion. Reduction in the aminopeptidase activity with LpNA in the H. armigera larvae was compensated with an induction of aminopeptidase activity with ApNA. Our findings could be helpful to further dissect the roles of plant inducible LAPs in the direct plant defense against herbivory.


Assuntos
Cajanus/enzimologia , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Leucil Aminopeptidase/farmacologia , Mariposas/fisiologia , Animais , Dieta , Eletroforese em Gel de Poliacrilamida , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Serina Proteases/metabolismo , Análise de Sobrevida
12.
Aquat Toxicol ; 105(3-4): 609-17, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21946169

RESUMO

Ingested pollutants may elicit digestive toxicity following incorporation into consumer tissues. This post-assimilatory toxicity may include tissue damage influencing synthesis of digestive enzymes, gut transit time and absorption of nutrients as well as pollutants by the gut epithelium. This study investigated impacts of chronic field exposure on gut residence time (GRT), feces elimination rate (FER), extracellular digestive protease activities and gut pH in grass shrimp Palaemonetes pugio. Adult shrimp were collected from differentially impacted sites within the New York/New Jersey Harbor Estuary and fed prepared meals containing fluorescent or near-infrared markers and analyzed for digestive toxicity. Relationships between digestive parameters and assimilation efficiencies (AE) for Cd, Hg and organic carbon reported previously were also analyzed. Minimum GRT did not vary significantly for field-collected shrimp, but was positively correlated with Cd, but not Hg or carbon, AE. FER was not impacted by field exposure. Digestive protease activities exhibited a marked decrease in grass shrimp from impacted field sites relative to reference shrimp. Relationships between the assimilation of elements and digestive physiology in field-collected shrimp suggest that digestive plasticity (increasing GRT) may be important in compensating for post-assimilatory digestive toxicity (reduced protease activities) in order to maintain nutrient assimilation. Stress-induced variability in digestive function among grass shrimp populations may, in turn, enhance the assimilation of non-essential elements, such as Cd.


Assuntos
Cádmio/toxicidade , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Mercúrio/toxicidade , Palaemonidae/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Cádmio/farmacocinética , Carbono/metabolismo , Citofotometria , Dieta , Contaminação de Alimentos , Trânsito Gastrointestinal/efeitos dos fármacos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Mercúrio/farmacocinética , Palaemonidae/fisiologia , Peptídeo Hidrolases/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Poluentes Químicos da Água/farmacocinética
13.
Ann N Y Acad Sci ; 1219 Suppl 1: E1-E23, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21332758

RESUMO

Presented by the New York Academy of Sciences, the U.S. Food and Drug Administration (FDA), and the U.S. Office of Dietary Supplements of the National Institutes of Health, the symposium "Probiotic Foods and Supplements: The Science and Regulations of Labeling," was held on June 12, 2010 at the New York Academy of Sciences, New York, NY, the goals of which were to facilitate the exchange of ideas regarding labeling and substantiation of claims for probiotics among academic, industry, and regulatory professionals, and to discuss ways to translate and communicate research results in a truthful way to the consumer and to such health professionals as physicians, pharmacists, and dieticians. The target audience for this symposium included academicians interested in conducting research on the health benefits of probiotics; scientists; communications personnel, and regulatory specialists from companies involved in, or interested in, the marketing of probiotics; U.S. government regulatory experts tasked with oversight of probiotic foods and dietary supplement products; and other experts in the field interested in the development of probiotics for the U.S. market.


Assuntos
Suplementos Nutricionais , Rotulagem de Alimentos/legislação & jurisprudência , Ciências da Nutrição/tendências , Probióticos , United States Food and Drug Administration/legislação & jurisprudência , Publicidade/legislação & jurisprudência , Publicidade/métodos , Comunicação , Congressos como Assunto , Suplementos Nutricionais/normas , Suplementos Nutricionais/provisão & distribuição , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Rotulagem de Alimentos/normas , Saúde , Humanos , Modelos Biológicos , Ciências da Nutrição/legislação & jurisprudência , Probióticos/farmacologia , Probióticos/normas , Probióticos/provisão & distribuição , Probióticos/uso terapêutico , Relação Estrutura-Atividade , Estados Unidos
14.
J Exp Biol ; 213(5): 798-807, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20154196

RESUMO

It can be hypothesized that species with a wide or variable food niche are able to adjust their digestive physiology to current food type. In diet specialists, however, the capacity for such presumably costly plasticity is not necessary and flexibility of digestive physiology should be lower. Recently, we found that ontogenetic changes in the activity of digestive enzymes in house sparrow, a species that gradually consumes more carbohydrates during ontogeny, are strongly modified by diet composition. In the present study we examined digestive flexibility of nestling and adult zebra finches, typical diet specialists that consume only seeds after hatching. Both adult and nestling zebra finches could not thrive on a protein-rich and carbohydrate-free diet that supported normal development of young house sparrows. Mass-specific activity of intestinal carbohydrases (maltase and sucrase) was not elevated by higher diet carbohydrate content in both nestling and adult birds. Mass-specific activity of maltase changed less during ontogenetic development in zebra finch than in house sparrow. We conclude that the digestive physiology of zebra finch is adapted to process carbohydrate-rich food after hatching and is much less flexible than in house sparrow. We hypothesize that this difference might reflect the lack of a diet switch during ontogeny or result from high specialization to a narrow diet niche.


Assuntos
Dieta , Fenômenos Fisiológicos do Sistema Digestório , Fenômenos Ecológicos e Ambientais , Comportamento Alimentar/fisiologia , Tentilhões/fisiologia , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Carboidratos da Dieta/farmacologia , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Masculino , Comportamento de Nidação/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Especificidade de Órgãos/efeitos dos fármacos , Análise de Sobrevida
15.
J Exp Biol ; 212(Pt 16): 2571-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19648402

RESUMO

The anterior midgut of the larval yellow fever mosquito Aedes aegypti generates a luminal pH in excess of 10 in vivo and similar values are attained by isolated and perfused anterior midgut segments after stimulation with submicromolar serotonin. In the present study we investigated the mechanisms of strong luminal alkalinization using the intracellular fluorescent indicator BCECF-AM. Following stimulation with serotonin, we observed that intracellular pH (pH(i)) of the anterior midgut increased from a mean of 6.89 to a mean of 7.62, whereas pH(i) of the posterior midgut did not change in response to serotonin. Moreover, a further increase of pH(i) to 8.58 occurred when the pH of the luminal perfusate was raised to an in vivo-like value of 10.0. Luminal Zn(2+) (10 micromol l(-1)), an inhibitor of conductive proton pathways, did not inhibit the increase in pH(i), the transepithelial voltage, or the capacity of the isolated tissue to alkalinize the lumen. Finally, the transapical voltage did not significantly respond to luminal pH changes induced either by perfusion with pH 10 or by stopping the luminal perfusion with unbuffered solution which results in spontaneous luminal alkalinization. Together, these results seem to rule out the involvement of conductive pathways for proton absorption across the apical membrane and suggest that a serotonin-induced alkaline pH(i) plays an important role in the generation of an alkaline lumen.


Assuntos
Larva/fisiologia , Serotonina/farmacologia , Absorção , Aedes/fisiologia , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Sistema Digestório/efeitos dos fármacos , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Prótons , Febre Amarela/fisiopatologia
16.
J Biol Regul Homeost Agents ; 23(2): 127-31, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19589295

RESUMO

It is well-known that digestion has a pivotal role in maintaining a state of wellbeing. The influence of certain foods and some herbal drugs has been ascertained. Epidemiological data show that the Mediterranean diet, with a high consumption of fresh vegetables and fruit, mainly citrus, has a beneficial effect and plays a protective gastrointestinal role. Previously, we assessed the influence on the eventual occurrence of symptoms during digestion of an iced dessert containing a mixture of digestive plant extracts, citrus juices and liquors, showing that its ingestion does not cause significant gastrointestinal symptoms in healthy volunteers. Taking into consideration that sensory properties of food may also influence digestion, we also evaluated the palatability of the product. In order to evaluate the effect of different tastes on the digestive processes, we performed a further similar evaluation with two new flavours. The ingestion of these iced desserts at the end of the meal does not cause significant gastrointestinal symptoms. Moreover, palatability median score shows a good appreciation of the products. Therefore, the combination of digestive herbs, citrus juice and liquors in different flavours gives rise to a product with a positive mix of good palatability, favourable acceptance and herbal constituents, able to maintain a good digestive condition.


Assuntos
Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Aromatizantes/administração & dosagem , Adulto , Idoso , Feminino , Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Olfato , Paladar , Temperatura , Adulto Jovem
17.
J Exp Zool A Ecol Genet Physiol ; 311(9): 719-26, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19637352

RESUMO

Isolated anterior midguts of larval Aedes aegypti were bathed in aerated mosquito saline containing serotonin (0.2 micromol L(-1)) and perfused with NaCl (100 mmol L(-1)). The lumen negative transepithelial voltage (V(te)) was measured and luminal alkalinization was determined through the color change of luminal m-cresol purple from yellow to purple after luminal perfusion stops. Addition of 10 mmol L(-1) amino acids (arginine, glutamine, histidine or proline) or dicarboxylic acids (malate or succinate) to the luminal perfusate resulted in more negative V(te) values, whereas addition of glucose was without effect. In the presence of TRIS chloride as luminal perfusate, addition of nutrients did not change V(te). These results are consistent with Na(+)-dependent absorption of amino acids and dicarboxylic acids. Effects of serotonin withdrawal indicated that nutrient absorption is stimulated by this hormone. Strong luminal alkalinization was observed with mosquito saline containing serotonin on the hemolymph-side and 100 mmol L(-1) NaCl in the lumen, indicating that alkalinization does not depend on luminal nutrients. Omission of glucose or dicarboxylic acids from the hemolymph-side solution had no effect on luminal alkalinization, whereas omission of amino acids significantly decelerated it. Re-addition of amino acids restored alkalinization, suggesting the involvement of amino acid metabolism in luminal alkalinization.


Assuntos
Aedes/fisiologia , Aminoácidos/farmacologia , Ácidos Dicarboxílicos/farmacologia , Sistema Digestório/efeitos dos fármacos , Glucose/farmacologia , Animais , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Combinação de Medicamentos , Eletrofisiologia , Epitélio/efeitos dos fármacos , Epitélio/fisiologia , Hemolinfa/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Larva/efeitos dos fármacos , Larva/fisiologia , Malatos/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Perfusão , Serotonina/farmacologia , Ácido Succínico/farmacologia
18.
Neurol Clin ; 27(3): 605-31, v, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19555824
19.
Rev. argent. anestesiol ; 67(2): 119-129, abr.-jun. 2009. ilus, tab, graf
Artigo em Espanhol | BINACIS | ID: bin-124266

RESUMO

Introducción: Tradicionalmente se ha promocionado un ayuno total preoperatorio de 8 a 12 horas con el único objetivo de disminuir el contenido gástrico y así evitar la aspiración pulmonar. Los conocimientos actuales de fisiología gástrica y de ayuno demuestran que una dieta prolongada facilita las condiciones para el vómito, pero además tiene un efecto deletéreo sobre el metabolismo del paciente. Material y métodos: Se realiza un análisis bibliográfico sobre el tema en libros, PubMed y Google Advanced Search (1848-2009), publicaciones en español e inglés, en el que se incluyen ensayos clínicos, revisiones bibliográficas, cartas, editoriales, guías prácticas, meta análisis y revisiones Cochrane. Resultados: La ingestión preoperatoria de agua reduce significativa mente el volumen y la acidez gástrica, y la de glúcidos disminuye significativa mente la resistencia a la insulina y el catabolismo muscular. El vaciado gástrico de sólidos se completa en 8 horas, de lácteos en 6, de leche materna en 4 y de líquidos claros con azúcares en 2 horas. Discusión: Los estudios de fisiología gástrica y del ayuno revelan que una dieta total de 8 horas favorece las condiciones que facilitan el vómito: elevado contenido y acidez gástricos. Además, genera procesos catabólicos que se expresan en insulinoresistencia, deshidratación e hipoglucemia. Conclusión: Las pautas de ayuno preoperatorio promovidas por la A.S.A desde 1999 demuestran ser eficaces para evitar la aspiración pulmonar del contenido gástrico, pero además tienen el beneficio de evitar el catabolismo y la deshidratación, y mejorar el estado clínico y la sensación de bienestar del paciente.(AU)


Introduction: Traditionally, a preoperative fasting of 8 to 12 hours was recommended, with the only purpose of reducing the gastric content to avoid pulmonary aspiration. Current information about gastric and fasting physiology shows that an extended fasting facilitates vomiting conditions and also has a deleterious effect on the patients metabolism. Material and Methods: Bibliographic analysis on this subject is carried out in books, PubMed and Google Advanced Search, (1848 - 2009), in Spanish and English, including clinical trials, bibliographic revisions, letters, editorials, practical guidelines, meta analyses and Cochrane reviews. Results: Preoperative ingestion of water significantly reduces gastric volume and acidity. The preoperative glucide intake significantly diminishes insulin resistance and muscular catabolism. Gastric emptying of solids is completed in 8 hours, of milk products in 6 hours, of human milk in 4 hours and of clear liquids with sugar in 2 hours. Discussion: Studies on gastric and fasting physiology reveal that a total fasting of 8 hours favors the conditions that facilitate vomiting: high acidity and gastric contents. It also generates catabolic processes that are expressed in insulin resistance, dehydration and hypoglycemia. Conclusion: The preoperative guidelines recommended by A.S.A since 1999 have proven to be effective in avoiding pulmonary aspiration of the gastric content as well as catabolism and dehydration, improving clinical status and the patients feeling of comfort.(AU)


IntroduþÒo: Tradicionalmente, tem sido proposto um jejum total pré-operatório de 8 a 12 horas com o único objetivo de diminuir o conteúdo gástrico e, deste modo, evitar a aspiraþÒo pulmonar. Os conhecimentos atuais sobre fisiologia gástrica e jejum provam que uma dieta prolongada nÒo só facilita as condiþÒoes para o v¶mito, mas também tem um efeito prejudicial sobre o metabolismo do paciente. Material e métodos: Foi feita uma análise bibliográfica sobre o tema em livros, PubMed e Google Advanced Search (1848-2009), publicaþ§es em espanhol e inglÛs, incluindo testes clínicos, revis§es bibliográficas, cartas, editoriais, guias práticos, meta-análise e revis§es Cochrane. Resultados: A ingestao pré-operatória de água reduz significativamente o volume e a acidez gástrica, e a ingestao de glicídios diminui fortemente a resistencia a insulina e o catabolismo muscular. O esvaziamento gástrico de sólidos é completado em 8 horas, de lácteos em 6, de leite materno em 4 e de líquidos claros com aþúcares em 2 horas. DiscussÒo: Os estudos de fisiologia gástrica e jejum revelam que uma dieta total de 8 horas favorece as condiþ§es de ocorrencia de vómito: elevado conteúdo e acidez gástricos. Por outro lado, gera processos catabólicos que se manifestam como insulino-resistencia, desidrataþÒo e hipoglicemia. ConclusÒo: As pautas de jejum pré-operatório propostas pela A.S.A desde 1999 sÒo eficazes para evitar a aspiraþÒo pulmonar do conteúdo gástrico, e também tÛm o beneficio adicional de evitar o catabolismo e a desidrataþÒo, e melhorar o estado clínico e a sensaþÒo de bem-estar do paciente.(AU)


Assuntos
Anestesia Geral/normas , Cuidados Pré-Operatórios , Jejum/metabolismo , Jejum/fisiologia , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Conteúdo Gastrointestinal/efeitos dos fármacos , Esvaziamento Gástrico/fisiologia , Ingestão de Líquidos/fisiologia , Estresse Fisiológico/fisiologia , Resistência à Insulina/fisiologia , Refluxo Gastroesofágico/prevenção & controle
20.
Sci Total Environ ; 407(3): 1080-8, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19010515

RESUMO

Concentrations of both essential (Fe, Cu, Zn) and non essential (Cd, Hg and Pb) metals were measured in the digestive gland and mantle of female cephalopods Sepia officinalis captured in two distinct lagoons in Portugal: Aveiro Lagoon, with a history of anthropogenic and industrial pollution, and Formosa Lagoon receiving urban effluents. We provide evidence for the following: (1) the digestive gland is the main target organ for both essential and non essential metals, frequently containing concentrations few orders of magnitude higher as compared to mantle; the sole exception from this was the Hg that is equally distributed in the two tissues; (2) unexpectedly, the higher levels of metals were found in animals captured in the less polluted lagoon, except for Cd whose bioavailability in Aveiro lagoon might be related to industrial sources, while the influence of Cd speciation in local pray composition should not be ruled out (3) size influenced metal concentration in different way: smaller individuals accumulated significantly more Cu, while Hg concentrations showed the opposite trend; (4) Cd is positively correlated to Zn and Cu in digestive gland of specimens collected in spring in Aveiro Lagoon, and no relationship was found in Formosa Lagoon; (5) the molar ratios Cd:Zn and Cd:Cu in digestive gland increased with body weight in specimens from Aveiro area, both ratios becoming particularly higher in older individuals. Metal-specific accumulation patterns in both mantle and digestive gland at the two sites are discussed in the light of their toxicological implications.


Assuntos
Metais/toxicidade , Sepia/fisiologia , Animais , Oceano Atlântico , Cádmio/metabolismo , Cádmio/toxicidade , Sistema Digestório/efeitos dos fármacos , Fenômenos Fisiológicos do Sistema Digestório/efeitos dos fármacos , Fenômenos Fisiológicos do Sistema Digestório/fisiologia , Chumbo/toxicidade , Mercúrio/toxicidade , Portugal , Estações do Ano , Água do Mar , Sepia/efeitos dos fármacos , Zinco/metabolismo , Zinco/toxicidade
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