Accuracy of real-time shear wave elastography in the assessment of normal small intestine mucosa in dogs.

The aim of the study was to assess the physiological stiffness of the normal canine jejunal mucosa based on shear wave elastography. The study was carried out on 60 dogs. In all the animals studied, the abdominal ultrasound was carried out using the SuperSonic Imagine Aixplorer system. The site of the jejunal elastography was determined using standard ultrasonography and all the measurements were carried out thrice. The stiffness of the area examined was determined during each measurement. Mean values were calculated based on the results obtained. The normal stiffness of the jejunal mucosa ranged from 1.305 kPa to 9.319 kPa (mean 5.31 ± 2.04 kPa). Based on our findings, we determined the range of normal values of the jejunal mucosal stiffness in healthy dogs. In addition, shear wave elastography was found to be safe and easy to perform. Moreover, it did not require anaesthesia or patient immobilisation for long periods.

ASSESSMENT OF THE GASTRO-JEJUNO-DUODENAL TRANSIT AFTER JEJUNAL POUCH INTERPOSITION / AVALIAÇÃO DO TRÂNSITO GASTROJEJUNODUODENAL APÓS INTERPOSIÇÃO DE ALÇA JEJUNAL

Background : The jejunal pouch interposition between the gastric body and the duodenum after the gastrectomy, although not frequent in the surgical practice today, has been successfully employed for the prevention and treatment of the postgastrectomy syndromes. In the latter, it is included the dumping syndrome, which affects 13-58% of the patients who undergo gastrectomy. Aim : Retrospective assessment of the results of this procedure for the prevention of the dumping syndrome. Methods : Fourty patients were selected and treatetd surgically for peptic ulcer, between 1965 and 1970. Of these, 29 underwent vagotomy, antrectomy, gastrojejunalduodenostomy at the lesser curvature level, and the 11 remaining were submitted to vagotomy, antrectomy, gastrojejunal-duodenostomy at the greater curvature level. The gastro-jejuno-duodenal transit was assessed in the immediate or late postoperative with the contrasted study of the esophagus, stomach and duodenum. The clinical evolution was assessed according to the Visick grade. Results : Of the 40 patients, 28 were followed with the contrast evaluation in the late postoperative. Among those who were followed until the first month (n=22), 20 (90%) had slow gastro-jejuno-duodenal transit and in two (10%) the transit was normal. Among those who were followed after the first month (n=16), three (19%) and 13 (81%) had slow and normal gastric emptying, respectively. None had the contrasted exam compatible with the dumping syndrome. Among the 40 patients, 22 underwent postoperative clinical evaluation. Of these, 19 (86,5%) had excellent and good results (Visick 1 and 2, respectively). Conclusions : The jejunal pouch interposition showed to be a very effective surgical procedure for the prevention of the dumping syndrome in gastrectomized patients.

Racional : A interposição de alça jejunal entre o corpo gástrico e o duodeno após a antrectomia, apesar de pouco frequente na prática cirúrgica atual, tem sido empregada com sucesso na prevenção e tratamento das síndromes pós-gastrectomias. Entre estas se inclui a síndrome de dumping, que acomete 13-58% dos pacientes gastrectomizados. Objetivo : Avaliação retrospectiva dos resultados desse procedimento na prevenção da síndrome de dumping. Métodos : Foram selecionados 40 pacientes todos encaminhados para tratamento cirúrgico de úlcera cloridropéptica entre 1965 e 1970. Destes, 29 foram submetidos à vagotomia, antrectomia, gastrojejunoduodenostomia no nível da pequena curvatura, e os 11 restantes à vagotomia, antrectomia, gastrojejunoduodenostomia no nível da grande curvatura. O trânsito gastrojejunoduodenal foi avaliado no pós-operatório imediato ou tardio por meio do estudo contrastado de esôfago, estômago e duodeno. A evolução clínica no pós-operatório foi avaliada segundo a classificação de Visick. Resultados : Dos 40 pacientes, 28 foram acompanhados com o estudo contrastado no pós-operatório tardio. Entre aqueles de até o 1º mês de pós-operatório (n=22), 20 (90%) apresentaram o trânsito gastrojejunoduodenal lento e dois (10%) tiveram o trânsito normal. Entre os que puderam ser acompanhados após o 1º mês (n=16), três (19%) e 13 (81%) mostraram o esvaziamento gástrico lento e normal, respectivamente. Nenhum apresentou o estudo contrastado compatível com a síndrome de dumping. Entre os 40 doentes, 22 foram submetidos à avaliação clínica pós-operatória. Destes, 19 (86,5%) apresentaram excelentes e bons resultados (Visick 1 e 2, respectivamente). Conclusões : A interposição de alça jejunal mostrou-se procedimento cirúrgico bastante eficaz na prevenção da síndrome de dumping em pacientes gastrectomizados.

ASSESSMENT OF THE GASTRO-JEJUNO-DUODENAL TRANSIT AFTER JEJUNAL POUCH INTERPOSITION.

BACKGROUND: The jejunal pouch interposition between the gastric body and the duodenum after the gastrectomy, although not frequent in the surgical practice today, has been successfully employed for the prevention and treatment of the postgastrectomy syndromes. In the latter, it is included the dumping syndrome, which affects 13-58% of the patients who undergo gastrectomy. AIM: Retrospective assessment of the results of this procedure for the prevention of the dumping syndrome. METHODS: Fourty patients were selected and treatetd surgically for peptic ulcer, between 1965 and 1970. Of these, 29 underwent vagotomy, antrectomy, gastrojejunalduodenostomy at the lesser curvature level, and the 11 remaining were submitted to vagotomy, antrectomy, gastrojejunal-duodenostomy at the greater curvature level. The gastro-jejuno-duodenal transit was assessed in the immediate or late postoperative with the contrasted study of the esophagus, stomach and duodenum. The clinical evolution was assessed according to the Visick grade. RESULTS: Of the 40 patients, 28 were followed with the contrast evaluation in the late postoperative. Among those who were followed until the first month (n=22), 20 (90%) had slow gastro-jejuno-duodenal transit and in two (10%) the transit was normal. Among those who were followed after the first month (n=16), three (19%) and 13 (81%) had slow and normal gastric emptying, respectively. None had the contrasted exam compatible with the dumping syndrome. Among the 40 patients, 22 underwent postoperative clinical evaluation. Of these, 19 (86,5%) had excellent and good results (Visick 1 and 2, respectively). CONCLUSIONS: The jejunal pouch interposition showed to be a very effective surgical procedure for the prevention of the dumping syndrome in gastrectomized patients.

In vitro assessment of epithelial electrical resistance in human esophageal and jejunal mucosae and in Caco-2 cell layers.

OBJECTIVE: There is a need for a technique allowing studies of human mucosal specimens collected during different clinical conditions. This study elucidates if square wave pulse analysis discriminates between epithelial and transmural electrical resistance and if there is an association with transepithelial permeability of molecular probes. METHODS: Mucosae from esophagus (surgical resections: n = 14; endoscopic biopsies: n = 15) and jejunum (n = 12) and Caco-2 cell monolayers were investigated in Ussing chambers. Transmural and epithelial electrical resistance were recorded by the use of standardized current pulses. Permeability was assessed using two fluorescein-labeled probes (weight 376 and 4000 Da). RESULTS: Baseline epithelial electrical resistance was higher in esophageal mucosa (~280 Ω*cm(2)), than in jejunal (~10 Ω*cm(2)) and Caco-2 cells (~140 Ω*cm(2)). The subepithelial contribution to the transmural resistance was higher in jejunal preparations (+88%) and Caco-2 cells (+75%), than in esophageal (+30%). During hypoxia the subepithelial resistance was unchanged, whereas the epithelial resistance decreased significantly in jejunal mucosa and Caco-2 cells. These findings coincided with increased transepithelial probe permeability and signs of disturbed morphology. Esophageal epithelia were resistant to hypoxia. However, exposure to deoxycholic acid and trypsin abolished the esophageal epithelial resistance and increased probe permeability. Endoscopic esophageal biopsies from patients with erosive reflux disease exhibited significantly lower epithelial resistance and higher current than healthy subjects. CONCLUSION: Square wave pulse analysis in Ussing chambers is suitable for assessment of epithelial electrical resistance that can reflect transepithelial permeability of molecular probes with known size. Moreover, the technique discriminated between healthy and reflux-diseased esophageal mucosal biopsies.

Reversed bowel segments for the treatment of short bowel syndrome: assessment of their minimal length in correlation with electromyographic pattern in the rat.

Reversal of a distal intestinal loop is a surgical therapy intended to cure rapid intestinal transit in short bowel syndrome. To be active, a reversed loop must present a retrograde propagation of electromyographic patterns and must not be so long as to cause total obstruction. The aim of the current study was to propose methods to calculate the minimal length of the intestinal reversed loop taking into consideration the two previous conditions. Intestinal electromyograms were recorded in 65 rats at short-term (4 days after surgery) and ten rats at long-term (50 days after surgery). Control rats demonstrated that the preprandial regular spiking activity (RSA) of the migrating myoelectrical complex (MMC) extended simultaneously a definite part of the intestine which corresponds to the minimal length to reverse. A similar result can be obtained from a trigonometric representation. Whatever the method, the minimal lengths allowing the recording of RSA decreased along the rat intestine from 6 cm (proximal jejunum) to 4 cm (distal ileum). The experiments demonstrated that shorter loops did not present the preprandial RSA. In conclusion, the minimal reversed length depends on intestinal electromyographic parameters and, thereby, on the intestinal level.

Assessment of gut intraepithelial lymphocytes during late gestation and the neonatal period.

Intraepithelial lymphocyte counts (IEL % enterocytes) were carried out in histological samples of jejunal, ileal and appendiceal mucosa of 39 neonates, aged from birth to 28 days. Correlations between IEL counts and developmental factors, namely gestational age, birth weight and intrauterine growth, as well as neonatal infections or feeding state were performed. No significant differences were observed among neonates grouped according to birth weight, intrauterine growth or neonatal infections. The pattern of feeding, however was associated with significantly higher IEL counts (p < 0.02) in the ileum in oral/enterally fed neonates than in the unfed or parenterally fed. Full-term neonates also had higher counts in the ileum (p < 0.02). In this group, oral/enterally fed neonates had the higher values. Thus, besides in utero development, the pattern of feeding might be considered as an important modulating factor on IEL postnatal expansion.

Quantitative assessment of villous motility.

A videomicroscopic method was used to quantitatively analyze villous motility in the dog small intestine. The frequency and duration of villous contractions (retractions) were measured in the duodenum, midjejunum, and distal ileum under controlled conditions. A pronounced gradient of villous motility was evident along the bowel. The duodenum exhibited the highest frequency (7.3 +/- 0.1/min) and longest duration (2.6 +/- 0.1 s) of contraction; the jejunum exhibited an intermediate frequency and duration of contraction (4.0 +/- 0.1/min, 2.1 +/- 0.1 s), and the lowest values were measured in the ileum (2.0 +/- 0.1/min and 1.8 +/- 0.1 s). In contrast to the retraction movements, the frequency of pendular villous movements (whipping, swaying movements without shortening) was highest in the jejunum and lowest in the duodenum. The frequency and duration of villous contractions (retractions) remained relatively constant over a 2-h observation period. Reducing mucosal surface temperature from 38 to 30 degrees C caused the frequency of contraction to fall by 33% and the duration to increase by 106%. Varying the suffusate pH within the physiological range of 5.0-7.4 produced no significant effects on jejunal villous motility. Suffusion with glucose (140 and 280 mM) failed to alter villous motility. However, amino acid (15 and 30 mM) and fatty acid (10 mM) solutions significantly increased contraction frequency by 30-50% and 90%, respectively. The videomicroscopic method provides useful quantitative information, which should extend current knowledge regarding the regulation and physiological importance of villous motility.

Electrical assessment of functional lactase activity in conscious man.

Using an electrical technique for measuring transjejunal potential differences (PDs) in conscious man, we have estimated the electrogenic absorption of the hexoses liberated by hydrolysis of lactose which was infused into the jejunum of one normal control and 21 patients with diarrhoea. The results were compared with jejunal lactase levels determined from biopsy specimens taken from the recording site immediately after infusion. The PD evoked by 100 mM lactose was very significantly lower in patients with lactase levels below 4 units (lactase deficient) compared with subjects with normal lactase levels. There was also a significant correlation (r = 0.87, P less than 0.005) between the magnitude of the lactose potential (expressed as the ratio of the maximum glucose transfer potential) and the mucosal lactase level in the hypolactasic subjects but not in patients with normal lactase levels. Thus, in the subjects with lactase deficiency, the electrogenic transfer of hexose is clearly limited by the rate of lactose hydrolysis. Unlike other assessments of functional lactase activity, the electrical test provides a specific index of jejunal function and, moreover, can be adapted to investigate the possible disorders of small intestinal motility and secretion associated with hypolactasia.