Natural infection of gastrointestinal nematodes in long-nosed armadillos Dasypus novemcinctus Linnaeus, 1758 from Pantanal wetlands, Aquidauana sub-region, Mato Grosso do Sul State, with the description of Hadrostrongylus speciosum n. gen. et n. sp (Molineidae : Anoplostrongylinae)

This study evaluated the gastrointestinal helminth fauna of long-nosed armadillos, Dasypus novemcinctus, from the Pantanal wetlands, Aquidauana sub-region, Aquidauana County, Mato Grosso do Sul State, Brazil. Thirteen species of nematodes, comprising seven genera and four families, were recovered from their gastrointestinal tracts. The following descriptors of infection were determined: prevalence, variation of intensity, average intensity and abundance. Hadrostrongylus speciosum n. gen. et n. sp. is first described here. (c) 2006 Published by Elsevier B.V.

Influence of chlorine added to drinking water during the preslaughter feed withdrawal on microbiology and morphology of the broiler gastrointestinal tract

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desenvolvimento do Trato Gastrointestinal de Embriões Oriundos de Matrizes Pesadas de 30 e 60 Semanas de Idade

O objetivo deste trabalho foi investigar o efeito da idade das matrizes pesadas sobre o desenvolvimento do trato gastrointestinal (TGI) dos embriões no terço final do período de incubação, bem como a utilização das reservas do saco vitelino nas 24 h pós-eclosão, em pintos alimentados ou em jejum. Foram utilizados ovos férteis da linhagem Cobb 500, oriundos de matrizes pesadas com 30 e 60 semanas de idade. O desenvolvimento do TGI (proventrículo+moela, segmentos do intestino delgado e saco vitelino) foi estudado entre o 17º e 21º dias de incubação (Experimento 1). Nas 24 h pós-eclosão foi pesquisado o efeito da presença ou não de alimento no lúmen intestinal sobre a utilização das reservas do saco vitelino (Experimento 2). Os achados deste trabalho mostraram que, ao contrário do embrião, o desenvolvimento do intestino delgado e o peso do saco vitelino não sofreram influência da idade das matrizes. Na fase pós-eclosão, na ausência de alimento, o desenvolvimento do intestino delgado foi maior nas matrizes com 60 semanas, sendo dependente do crescimento do jejuno. A presença do alimento no lúmen teve influência na utilização das reservas do saco vitelino apenas nas matrizes com 30 semanas de idade. Os resultados deste experimento mostraram que a idade da matriz é importante fator no desenvolvimento do trato gastrointestinal do embrião, sendo fator relevante no crescimento pós-ecloão dos pintos.

Effects of corn particle size and physical form of the diet on the gastrointestinal structures of broiler chickens

The objective of this experiment was to investigate the effects of different particle sizes, expressed as Geometric Mean Diameter (GMD) of corn (0.336mm, 0.585mm, 0.856mm and 1.12mm) of mash and pelleted broiler chicken diets on the weight of the gizzard, duodenum and jejunum+ileum; on the pH of the gizzard and small intestine and on the characteristics of the duodenal mucous layer (number and height of villi and crypt depth) in 42-day-old broilers. The physical form and the particle size of the diet had no significant effect on gizzard and intestine pH (p > 0.05). A greater gizzard weight was seen in the birds receiving pelleted diet and particle size of 0.336mm (p < 0.008). However, for the particle sizes of 0.856 and 1.12 mm, a greater weight was found in birds that received mash diet (p < 0.039 and p < 0.006, respectively). Also, gizzard weight was greater with increasing corn GMD independent of the physical form of the diet. In the mash diet, the increase in particle size promoted a quadratic response in the weight of duodenum and jejunum + ileum. The pelleted diet promoted a greater number of villi per transverse duodenum cut (p < 0.007) and greater crypt depth (p < 0.05). As the particle size increased, there was a linear increase of villus height and crypt depth in the duodenum, irrespective of the physical form of the diet.

Gastrointestinal nematode infection in beef cattle of different genetic groups in Brazil

Resistance to natural infection by gastrointestinal nematodes was compared in 67 female calves of the following genetic groups: Nelore (NX); 1/2 Senepol + 1/2 Nelore (SN); and 1/2 Aberdeen Angus + 1/2 Nelore (AN). The NX (n = 26), SN (n = 23) and AN (n = 18) animals were monitored for 14 months, during which they remained without treatment, allowed to graze in a tropical environment. Eggs per gram of feces (EPG), coprocultures and packed cell volume (PCV) were carried out monthly. No significant effects of the interaction between the genetic groups and month/year of collection and the genetic group on the EPG were found, but there was a significant influence of the month of collection (P < 0.01). The monthly PCV measurements did not differ for the animals of the three genetic groups and there was no association found between the EPG and PCV. The animals of the SN and NX groups showed similar numbers of EPG with results zero, while for the AN group these numbers were significantly lower (P < 0.05). Although the NX group had a large number of EPG with results zero, it also contained many animals with high counts, meaning this group had higher averages during the entire study period. The following nematode genera were found in the coprocultures: Haemonchus, Cooperia, Oesophagostomum and Trichostrongylus, the latter in smallest proportion. There was no significant difference between the genetic groups for averages of all parasites identified, except Cooperia, which were present in higher numbers in the animals of the NX group (P < 0.05). The results obtained in this experiment suggest that the use of Bos taurus x Bos indicus crossbreeds can be a good strategy to reduce the use of chemical control in Brazil. (C) 2009 Elsevier B.V. All rights reserved.

Alginate-chitosan systems: In vitro controlled release of triamcinolone and in vivo gastrointestinal transit

The aim of this study was to develop multiparticulate therapeutic systems of alginate (AL) and chitosan (CS) containing triamcinolone (TC) to colonic drug delivery. Multiparticulate systems of AL-CS, prepared by a complex coacervation/ionotropic gelation method, were characterized for morphological and size aspects, swelling degree, encapsulation content and efficiency, in vitro release profile in different environments simulating the gastrointestinal tract (GIT) and in vivo gastrointestinal transit. The systems showed suitable morphological characteristics with particle diameters of approximately 1.6 mm. In simulated gastric environment, at pH 1.2, the capsules presented low degree of swelling and in vitro release of drug. A higher swelling degree was observed in simulated enteric environment, pH 7.5, followed by erosion. Practically all the drug was released after 6 h of in vitro assay. The in vivo analysis of gastrointestinal transit, carried out in rats, showed that the systems passed practically intact through the stomach and did not show the same profile of swelling observed in the in vitro tests. It was possible to verify the presence of capsules in the colonic region of GIT. The results indicate that AL-CS multiparticulate systems can be used as an adjuvant for the preparation of therapeutic systems to colonic delivery of drugs. (C) 2010 Elsevier Ltd. All rights reserved.

AC Biosusceptometry as a Tool for Monitoring the Gastrointestinal Transit of Multiparticulate Drug Delivery System

Drug delivery systems based on natural polysaccharides, such as chitosan (CS) and pectin (PC), rather than on synthetic polymers, have been widely studied. Some reasons for that are low toxicity and costs and high biodegradability of the formers. A multiparticulate system based on CS and PC was developed in our laboratories, including the addition of an enteric polymer, cellulose acetate phtalate (CAP). Such improvement promoted stronger gastric and enteric resistances, as assessed in vitro, making the systems more selective to enzymatic degradation in the colon. Although in vitro dissolution tests can simulate some properties concerning the gastrointestinal transit (GT), collaborating to characterize the systems behavior in the biological fluids, frequently they do not result in satisfactory in vitro/in vivo correlations. The objective of this work was to follow in vivo the GT of the particles developed by means of AC biosusceptometry (ACB), a non-invasive and of low cost methodology. The particles containing ferrite in powder form were prepared by complex coacervation using an ideal 3:1:1 mass ratio for PC:CS:CAP. The magnetic particles were administered to healthy volunteers by oral route. The GT was monitored by using multi-sensor ACB system and the signal acquisition was performed every IS min until the colonic region was reached. By means of ACB technique, it was possible to acquiring images generated by the magnetic particles within the whole gastrointestinal tract including the colonic region. Variable particles transit times were observed among the volunteers, but without interference on the mapping of the particles until the colonic region. The particles were able to produce magnetic field strong enough to generate signals adequate for mapping the particles. The results suggest that integral particles reached the colon, after they resisted against gastric and enteric media. Studies associating transit time and in vivo drug release are in development in order to confirm the efficiency of the systems.

Biochemical, histopathological and clinical evaluation of delayed effects caused by methamidophos isoforms and TOCP in hens: Ameliorative effects using control of calcium homeostasis

This work evaluated the potential of the isoforms of methamidophos to cause organophosphorus-induced delayed neuropathy (OPIDN) in hens. In addition to inhibition of neuropathy target esterase (NTE) and acetylcholinesterase (AChE), calpain activation, spinal cord lesions and clinical signs were assessed. The isoforms (+)-, (+/-)- and (-)-methamidophos were administered at 50 mg/kg orally; tri-ortho-cresyl phosphate (TOCP) was administered (500 mg/kg, po) as positive control for delayed neuropathy. The TOCP hens showed greater than 80% and approximately 20% inhibition of NTE and AChE in hen brain, respectively. Among the isoforms of methamidophos, only the (+)-methamidophos was capable of inhibiting NTE activity (approximately 60%) with statistically significant difference compared to the control group. Calpain activity in brain increased by 40% in TOCP hens compared to the control group when measured 24h after dosing and remained high (18% over control) 21 days after dosing. Hens that received (+)-methamidophos had calpain activity 12% greater than controls. The histopathological findings and clinical signs corroborated the biochemical results that indicated the potential of the (+)-methamidophos to be the isoform responsible for OPIDN induction. Protection against OPIDN was examined using a treatment of 2 doses of nimodipine (1 mg/kg, i.m.) and one dose of calcium gluconate (5 mg/kg, iv.). The treatment decreased the effect of OPIDN-inducing TOCP and (+)-methamidophos on calpain activity, spinal cord lesions and clinical signs. (C) 2012 Elsevier B.V. All rights reserved.

The early systemic and gastrointestinal oxygenation effects of hemorrhagic shock resuscitation with hypertonic saline and hypertonic saline 6% dextran-70: A comparative study in dogs

The smaller volemic state from hypertonic (7.5%) saline (HS) solution administration in hemorrhagic shock can determine lesser systemic oxygen delivery and tissue oxygenation than conventional plasma expanders. In a model of hemorrhagic shock in dogs, we studied the systemic and gastrointestinal oxygenation effects of HS and hyperoncotic (6%) dextran-70 in combination with HS (HSD) solutions in comparison with lactated Ringer's (LR) and (6%) hydroxyethyl starch (HES) solutions. Forty-eight mongrel dogs were anesthetized, mechanically ventilated, and subjected to splenectomy. A gastric air tonometer was placed. in the stomach for intramucosal gastric CO2 (Pgco(2)) determination and for the calculation of intramucosal. pH (pHi):[pHi = pHa - log(Pgco(2)/Paco(2))].The dogs were hemorrhaged (42% of blood volume) to hold mean arterial blood pressure at 40-50 mm Hg over 30 min and were then resuscitated with LR (n = 12) in a 3:1 relation to removed blood volume; HS (n = 12), 6 mL / kg; HSD (n = 12), 6 mL / kg; and HES (mean molecular weight, 200 kDa; degree of substitution, 0.5) (n = 12) in a 1:1 relation to the removed blood volume. Hemodynamic, systemic, and gastric oxygenation variables were measured at baseline, after 30 min of hemorrhage, and 5, 60, and 120 min after intravascular fluid resuscitation. After fluid resuscitation, HS showed significantly lower arterial pH and mixed venous Po-2 and higher systemic oxygen uptake index and systemic oxygenation extraction than LR and HES (P < 0.05), whereas HSD showed significantly lower arterial pH than LR and HES (P < 0.05). Only HS and HSD did not return arterial pH and pHi to control levels (P < 0.05). In conclusion, all solutions improved systemic and gastrointestinal oxygenation after hemorrhagic shock in dogs. However, the HS solution showed the worst response in comparison to LR and HES solutions in relation to systemic oxygenation, whereas HSD showed intermediate values. HS and HSD solutions did not return regional oxygenation to control values.

Carcinogenesis of the upper gastrointestinal tract induced by N-methyl-N '-nitro-nitrosoguanidine and reflux of duodenal contents in the rat

Purpose: To investigate the combined effects of reflux of duodenal contents through the pylorus and treatment with N-methyl-N'-nitro-nitrosoguanidine ( MNNG) on the development of lesions in the glandular stomach, at the gastrojejunal anastomosis and in the forestomach of rats. Methods: Eighty Male Wistar rats were divided into 4 groups: G1: MNNG + Reflux, G2: Reflux, G3: MNNG and G4: Gastrostomy. MNNG was given in the drinking water ( 100 mg/ml) for 12 weeks and then two groups ( G1 and G2) were submitted to a gastrojejunal anastomosis followed by section of the afferent loop and suture of both stumps to allow reflux of duodenal contents through the pylorus. The animals were sacrificed 18 and 36 weeks after surgery. The lesions obtained in the antral mucosa, at the gastrojejunal anastomosis and in the forestomach were analysed histologically. Results: Duodenal reflux induced proliferative lesions at both glandular and squamous mucosa of the stomach. In the antrum, adenomatous hyperplasia (AH) was observed in 20% and 50% of the animals at the 18(th) and 36(th) weeks respectively. Aditionally 85% of the animals presented AH at the gastrojejunal anastomosis and 60% developed squamous hyperplasia at the squamous portion of the stomach. MNNG treatment plus duodenal reflux enhanced the development of malignant tumors at both glandular and squamous mucosa, since there were 30% of antral adenocarcinomas and 45% of squamous carcinomas at the 18th week and the frequency of these malignant tumors rose to 50% in the antrum and 65% in the squamous mucosa at the 36th week. Conclusion: The reflux of duodenal contents through the pylorus enhanced the development of proliferative lesions, benign and malignant, in the glandular stomach and in the forestomach of rats.

Upper gastrointestinal histopathological findings in children and adolescents with nonulcer dyspepsia with helicobacter pylori infection

Objectives: The aim of the study was to investigate the histopathological lesions in the upper gastrointestinal mucosa associated with Helicobacter pylori infection in children with nonulcer dyspepsia.Methods: A cross-sectional case-control study was performed on 185 Brazilian children and adolescents (4-17 years, mean 9.5 +/- 2.7 years), 63.2% girls, submitted to upper gastrointestinal endoscopy. The histopathological lesions of the esophageal and gastric mucosa were analyzed in biopsy samples.Results: H pylori infection was identified in 96 children (51.8%). Moderate to severe chronic active gastritis was present in antrum (70.5%) and corpus (45.2%), with higher grading in antrum than in corpus (P<0.05). The topographic distribution of inflammation was pangastritis (61.9%), followed by antral (32.1%) and corpus (5.9%). H pylori density was higher in antrum than in corpus. Intestinal metaplasia was not found in the H pylori-infected group, nor was significant gastric atrophy. The scores for esophagitis were significantly higher (P<0.05) in the noninfected group (1.4 +/- 0.8) than in the H pylori-infected group (1.07 +/- 0.9), with significant negative correlation (r = 0.29; P<0.05) with the scores of gastric inflammation.Conclusions: The prevalence of H pylori infection was high among children with dyspepsia and associated with moderate/severe degrees of gastric inflammation. The high scores of esophagitis in the noninfected group point to 2 distinct groups of pathological conditions sharing similar clinical patterns.

Gastrointestinal transit and disintegration of enteric coated magnetic tablets assessed by ac biosusceptometry

The oral administration is a common route in the drug therapy and the solid pharmaceutical forms are widely used. Although much about the performance of these formulations can be learned from in vitro studies using conventional methods, evaluation in vivo is essential in product development. The knowledge of the gastrointestinal transit and how the physiological variables can interfere with the disintegration and drug absorption is a prerequisite for development of dosage forms. The aim of this work was to employing the ac biosusceptometry (ACB) to monitoring magnetic tablets in the human gastrointestinal tract and to obtain the magnetic images of the disintegration process in the colonic region. The ac biosusceptometry showed accuracy in the quantification of the gastric residence time, the intestinal transit time and the disintegration time (DT) of the magnetic formulations in the human gastrointestinal tract. Moreover, ac biosusceptometry is a non-invasive technique, radiation-free and harmless to the volunteers, as well as an important research tool in the pharmaceutical, pharmacological and physiological investigations. (c) 2005 Elsevier B.V. All rights reserved.

Enteric coated magnetic HPMC capsules evaluated in human gastrointestinal tract by AC biosusceptometry

Purpose. To employ the AC Biosusceptometry (ACB) technique to evaluate in vitro and in vivo characteristics of enteric coated magnetic hydroxypropyl methylcellulose (HPMC) capsules and to image the disintegration process.Materials and Methods. HPMC capsules filled with ferrite (MnFe2O4) and coated with Eudragit (R) were evaluated using USP XXII method and administered to fasted volunteers. Single and multisensor ACB systems were used to characterize the gastrointestinal (GI) motility and to determine gastric residence time (GRT), small intestinal transit time (SITT) and orocaecal transit time (OCTT). Mean disintegration time (t (50)) was quantified from 50% increase of pixels in the imaging area.Results. In vitro and in vivo performance of the magnetic HPMC capsules as well as the disintegration process were monitored using ACB systems. The mean disintegration time (t (50)) calculated for in vitro was 25 +/- 5 min and for in vivo was 13 +/- 5 min. In vivo also were determined mean values for GRT (55 +/- 19 min), SITT (185 +/- 82 min) and OCTT (240 +/- 88 min).Conclusions. AC Biosusceptometry is a non-invasive technique originally proposed to monitoring pharmaceutical dosage forms orally administered and to image the disintegration process.

AC Biosusceptometry Technique to Evaluate the Gastrointestinal Transit of Pellets under Influence of Prandial State

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)