Crohn's disease: A retrospective analysis between computed tomography enterography, colonoscopy, and histopathology.

INTRODUCTION: To investigate the spectrum of computed tomography enterography (CTE) findings of active Crohn's disease (CD) in comparison to endoscopic, histopathologic and inflammatory markers. METHODS: Hospital records of 197 patients with known or suspected CD who underwent CTE over a period of 5 years were reviewed. Eighty-nine patients fulfilled the inclusion criteria. Three-point severity scores for endoscopy, pathology, and haematologic inflammatory markers were recorded. The findings on CTE were identified by three readers and correlated with endoscopic, pathologic, and haematologic severity scores. Statistical analysis was carried out employing a Pearson Chi square test and Fisher exact test. Receiver operating characteristic (ROC), visual grading characteristic (VGC) and Cohens' kappa analyses were performed. RESULTS: The CTE findings which were significantly correlated with the severity of active disease on endoscopy include bowel wall thickening, mucosal hyperenhancement, bilaminar stratified wall enhancement, transmural wall enhancement, and mesenteric fluid adjacent to diseased bowel (p < 0.05). Only bowel wall thickening and bilaminar stratified wall enhancement correlated with the pathological severity of active CD. ROC and VGC analysis demonstrated significantly higher areas under the curve (p < 0.0001) together with excellent inter-reader agreement (k = 0.86). CONCLUSION: CTE is a reliable tool for evaluating the severity of active disease and helps in the clinical decision pathway.

Urodynamic changes following intrathecal administration of morphine and fentanyl to dogs.

The effect of intrathecal (i.t.) injection of morphine and fentanyl on the urinary bladder was studied by ascending cystogram in 18 anaesthetized dogs. Examinations were performed before and 60 and 120 minutes after i.t. injection of saline (group I), 0.03 mg/kg morphine (group II) and 1.5 microg/kg fentanyl (group III). A significant increase in maximal volume and compliance and a decrease in voiding pressure were observed, indicating relaxation of the detrusor muscle after i.t. administration of morphine or fentanyl. I.t. morphine produced greater and more prolonged bladder relaxation than i.t. fentanyl. We conclude that i.t. morphine and fentanyl cause variable degrees of urinary retention. As fentanyl produced milder and shorter bladder relaxation than morphine, it may be useful in patients with urinary disturbances.

Urodynamic changes following intrathecal administration of morphine and fentanyl to dogs

The effect of intrathecal [IT] injection of morphine and fentanyl on the urinary bladder was studied by ascending cystogram in 18 anaesthetized dogs. Examinations were performed before and 60 and 120 minutes after IT injection of saline [group I], 0.03 mg/kg morphine [group II] and 1.5 microg/kg fentanyl [group III]. A significant increase in maximal volume and compliance and a decrease in voiding pressure were observed, indicating relaxation of the detrusor muscle after IT administration of morphine or fentanyl. IT morphine produced greater and more prolonged bladder relaxation than IT fentanyl. We conclude that IT morphine and fentanyl cause variable degrees of urinary retention. As fentanyl produced milder and shorter bladder relaxation than morphine, it may be useful in patients with urinary disturbances

Liver microsomal membrane fluidity and microsomal desaturase activities in adult spontaneously hypertensive rats.

OBJECTIVE: The purpose of the present study was to investigate liver microsomal membrane fluidity simultaneously with membrane fatty acid composition and desaturase activities in spontaneously hypertensive rats (SHR). DESIGN AND METHODS: The membrane fluidity was determined, after electron spin resonance (ESR) measurement, in SHR compared with normotensive Wistar-Kyoto (WKY) rats, by calculating the order parameter S from ESR spectra of 5-nitroxide stearate and 10-nitroxide stearate, used as spin-labelled fatty acids. Desaturase activities were measured by incubating SHR and WKY rat liver microsomes with [14C]-radiolabeled fatty acids as substrates for desaturation reactions. The fatty acid composition of liver microsomal membranes was determined by gas-liquid chromatography. RESULTS: Whereas no significant difference between S of 5-nitroxide stearate was observed for SHR and WKY rats, S of 10-nitroxide stearate was significantly lower in SHR than it was in WKY rat microsomal membrane, indicating that the core microsomal membrane fluidity was higher in SHR. Significant differences between fatty acid compositions were observed for SHR and WKY rat microsomal membranes. Delta9 and n-6 delta6 microsomal desaturase activities were significantly lower in SHR. CONCLUSION: These results suggest that the higher liver core microsomal membrane fluidity observed in SHR might be dependent on the increased proportion of mono-unsaturated fatty acids. Such observed modifications and the alterations in delta9 and n-6 delta6 desaturase activities suggest that an impaired polyunsaturated fatty acid biosynthesis is related to changes in microsomal membrane fluidity in hypertension.

Epithelial abnormalities in intestine and kidney of the spontaneously hypertensive rat.

A variety of perturbations of calcium metabolism are reported to occur in the spontaneously hypertensive rat (SHR) compared to its genetic control the Wistar-Kyoto rat (WKY), including significant dysfunction of calcium handling by the proximal renal tubule of the SHR, resulting in impaired active calcium transport in the gut and an apparent renal calcium leak. We explored the intestinal and renal epithelia of 12- to 14-week-old SHR and WKY using electron microscopy. Biochemical comparisons of these transport epithelia included measurements of three vitamin D dependent cellular proteins and one structural protein: alkaline phosphatase, intestinal CaBP9K, renal CaBP28K, and villin expression. Electron microscopy demonstrated a patchy loss in microvilli in the SHR, accounting for approximately 10 to 15% of the total microvillar surface. In the kidney, morphological abnormalities were observed only in the proximal renal tubule. Again, there was patchy loss of microvilli from the brush border membrane. In SHR duodenal alkaline phosphatase activity was significantly reduced compared to the WKY (0.145 +/- 0.002 v 0.186 +/- 0.002 integrated extinction/min/micron 3 X 10(3) brush border (P less than .001). Duodenal CaBP9K and renal CaBP28K were significantly reduced in SHR compared to WKY. There were no differences in villin expression. These data are consistent with the previously characterized disturbances of active calcium transport in the intestine and inappropriate renal calcium leak in the SHR. While a possible link between these disturbances and hypertension remains to be determined, this study provides supportive evidence for a primary disturbance in cell calcium handling and transporting epithelia in this form of genetic hypertension.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrastructural and functional abnormalities of intestinal and renal epithelium in the SHR.

Intestinal calcium transport, renal tubular calcium reabsorption, and plasma 1.25 (OH)2 vitamin D3 (calcitriol) levels have all been reported to be diminished in the spontaneously hypertensive rat (SHR) compared with its genetic control the Wistar Kyoto rat (WKY). In the present study, absorptive duodenal and renal tubular epithelia of 12- to 14-week-old male SHR and WKY were examined by electron microscopy to determine whether such disturbances could be related to structural abnormalities. Patchy loss of microvilli in both duodenal and proximal tubular epithelia was observed in the SHR, whereas brush border membrane was entirely normal in the WKY. Irregular spaces were observed between the basal aspects of SHR intestinal epithelial cells and their basement membrane. In addition, the average height of duodenal and renal microvilli was reduced in the SHR. Two specific markers of the brush border membrane, alkaline phosphatase and villin, as well as the cytoplasmic vitamin-D dependent calcium-binding proteins, CaBP9K and CaBP28K were determined. Duodenal alkaline phosphatase activity was reduced in the SHR, compared with the WKY: 0.145 +/- 0.002 vs. 0.186 +/- 0.002 IE/min.microns 3 x 10(3) brush border, mean +/- SEM, N = 10 pairs, P less than 0.001. However, duodenal villin expression was not different from that of the WKY. Duodenal CaBP9K and renal CaBP28K content was diminished in the SHR: 21.0 +/- 0.80 vs. 29.9 +/- 2.19 micrograms/mg protein, N = 6 pairs, P less than 0.01 for duodenum, and 4.47 +/- 0.39 vs. 7.67 +/- 0.54 micrograms/mg protein, N = 6 pairs, P less than 0.001 for kidney. These data showing structural and functional abnormalities of intestinal and kidney cells in the SHR appear to reflect a disorder of transporting epithelia which may be either intrinsic or related to reduced circulating calcitriol.

Vitamin D3 and glucose-6-phosphate dehydrogenase in rat duodenal epithelial cells.

A microdensitometric method was employed to determine enzyme activities in situ in undisrupted tissue rat duodenum. The effect of 1 alpha,25-dihydroxyvitamin D3 [1,25(OH)2D3] on glucose-6-phosphate dehydrogenase (G6PD) activity and on the two utilization pathways of synthesized NADPH, H1 (mixed function oxidation) and H2 (biosynthesis), was studied. In normal animals, a crypt-to-villus gradient of G6PD activity and of both NADPH utilization pathways was observed. A high level of NADPH utilization occurred predominantly via the H2 pathway. In vitamin D-deficient rat animals, G6PD activity in the middle part of the villus was approximately 60% lower than in normal animals [10.05 +/- 0.35 vs. 3.95 +/- 0.26 (means +/- SE) A585.min-1.micron-3 X 10(5), P less than 0.001] with reduced NADPH utilization via the H2 pathway (8.39 +/- 0.49 vs. 2.73 +/- 0.43 A585.min-1.micron-3 X 10(5), P less than 0.001) but not the H1 pathway (1.65 +/- 0.17 vs. 1.22 +/- 0.19 A585.min-1.micron-3 X 10(5), P = NS). Intraperitoneal administration of 1,25(OH)2D3 (500 pmol) to vitamin D-deficient animals resulted in increased G6PD activity within 30 min (4.09 +/- 0.38 vs. 5.51 +/- 0.39 A585.min-1.micron-3 X 10(5), P less than 0.05), attaining normal levels within 2 h. The H2 but not the H1 pathway of NADPH utilization increased significantly in response to 1,25(OH)2D3. This increase is essentially located in the basal and middle parts of the villus. Thus 1,25(OH)2D3 may influence biosynthesis in the duodenum via stimulation of G6PD activity and the H2 pathway of NADPH utilization.

Rapid (10-minute) stimulation of rat duodenal alkaline phosphatase activity by 1,25-dihydroxyvitamin D3.

Recent reports have suggested that the action of calcitriol is much more rapid than previously thought. It is thus possible that some actions do not depend on de novo protein synthesis. A precise microdensitometric technique has been used to characterize the time course of the intestinal brush border alkaline phosphatase (AP) response of rat duodenal villi to the administration of calcitriol as AP activity has been shown to be dependent on the vitamin D status of the animal. The technique enables AP activity to be determined in situ without tissue disruption. After ip administration of 200 ng calcitriol to vitamin D-deficient male Wistar AF rats, a biphasic AP response was observed with an early peak within 1 h (0.068 +/- 0.011 vs. 0.101 +/- 0.003 integrated extinction (IE) min.micron 3 X 10(3), P less than 0.05) and a second at between 6 and 8 h (0.088 +/- 0.005 vs. 0.172 +/- 0.003 IE/min.micron 3 X 10(3), P less than 0.001). In a further experiment, the early response to calcitriol was reexamined with observations at 0, 10, 30, 45, and 60 min after administration of either calcitriol or vehicle (n = 5 pairs per time point). AP activity was significantly increased in the calcitriol group compared with the vehicle-treated group as early as 10 min after administration (0.132 +/- 0.003 vs. 0.151 +/- 0.005 IE/min.micron 3 X 10(3), P less than 0.02) and reached a peak 45 min after administration at which time AP activity was equal to that found in normal vitamin D-replete animals (0.193 +/- 0.003 vs. 0.192 +/- 0.002 IE/min.micron (3) X 10(3), P greater than 0.5). The speed of this response indicates it to be unlikely to depend on de novo protein synthesis.

Effect of plasma levels of parathyroid hormone on NADPH pathways in kidney and liver.

NADPH available for mixed function oxidations (pathway 1) or biosynthetic processes (pathway 2) has been evaluated in different cells from rat liver and kidney. In addition, changes of the proportion of NADPH utilized in each pathway were demonstrated in the same cells from rats showing different circulating levels of parathyroid hormone (PTH). Quantitative levels of NADPH directed into each of these pathways have been measured and histologically located in sections from rat liver and kidney using quantitative cytochemistry and scanning and integrating microdensitometry. Centrilobular hepatocytes utilize the major amount of NADPH, either via pathway 1 or 2. Kidney cells utilize most NADPH via pathway 2, particularly in the distal part of the nephron. The cells of the pars recta have shown the highest capacity to utilize NADPH via pathway 1, which is about half that of centrilobular hepatocytes. In centrilobular cells, the presence of high plasma levels of PTH results in a significant increment of NADPH utilization either via pathway 1 or 2. In kidneys from rats showing high plasma levels of PTH, a selective increase in NADPH utilized via pathway 2 was observed in the distal convoluted tubule whereas a selective increase in NADPH utilized via pathway 1 was demonstrated in cells of the pars recta. These observations provide further information in the understanding of the physiology of kidney and liver cells.

In situ biochemical studies of intestinal alkaline phosphatase in normal and phosphate-depleted rats by microdensitometry.

A quantitative microdensitometric study has been designed to characterize in situ intestinal brush border-bound alkaline phosphatase of rat duodenal villosities. Intestinal slices were incubated with beta-glycerophosphate as substrate. Free phosphate liberated was precipitated in presence of a lead reagent as lead sulfide. The precipitate was quantified in situ by scanning and integrating microdensitometry. Kinetic parameters of the reaction were determined at 37 degrees C, pH 8.8, in the middle part of the villosities. Apparent Michaelis constant (Km) for beta-glycerophosphate was found to be 8.16 +/- 0.56 mM (mean +/- S.E.). Maximal enzyme activation was obtained at pH 8.5. Maximal inhibition of enzyme activity was observed in the presence of L-phenylalanine (30 mM) or theophylline (5 mM). Along the villosity axis, enzyme activity rose from the crypt up to the midportion of the villosity and finally decreased at the tip region. In phosphate-depleted rats, enzyme activity was increased in all portions of the villosity, with conservation of the same activity gradient. In this situation, kinetic analysis showed a marked decrease of Km, i.e. 4.56 +/- 0.39 mM (mean +/- S.E.) as compared to normal rats.