Biomedical subjects

S N Reddy

Publications and source records attributed to S N Reddy.

At least 19 recordsLinked to original sources

PubMed2002

Intrabiliary rupture of hydatid cyst: diagnosis with MRI and hepatobiliary isotope study.

Intrabiliary rupture is the most common complication of hepatic hydatid cyst yet it is unusual, occurring in only 3-17% of cases. The diagnosis is rarely difficult on ultrasound and CT when typical radiological features are present. In rare cases of complete evacuation, when characteristic findings of hydatid cyst are absent or when there is no evidence of the previous existence of liver hydatid cyst, the diagnosis may be difficult. In difficult cases, MRI, MRCP, ERCP and (99)Tc(m)-mebrofenin hepatobiliary scintigraphy are employed. We present a rare case of surgical obstructive jaundice due to rupture of a liver hydatid cyst into the biliary tract and gall bladder, with complete evacuation of its contents leading to misdiagnosis on CT and ultrasound. MRCP and (99)Tc(m)-mebrofenin hepatobiliary scintigraphy were able to establish a firm pre-operative diagnosis.

Aniline Compounds↗

PubMed2001

Spectral investigations on melanterite mineral from France.

EPR, Optical and IR spectral studies on a naturally occurring mineral melanterite are carried out at room temperature. EPR studies indicate the presence of Cu(II) ion in tetragonally distorted octahedral site and hyperfine lines could not be resolved due to higher concentration of the paramagnetic impurity in the mineral. Optical absorption spectrum is a characteristic of Fe(II) and Cu(II) ions. Crystal field parameters are evaluated. IR spectrum confirms the presence of water and sulphate ions.

Electron Spin Resonance Spectroscopy↗

PubMed2000

Nephroptosis: the Tc-99m glucoheptonate scan as a diagnostic method.

A 40-year-old man was examined because he was a potential "healthy" renal donor. However, the routine work-up before surgery revealed hypertension, although there was no family history of this condition. The patient was examined to exclude secondary causes of hypertension. Tc-99m glucoheptonate renal imaging showed nephroptosis of the right kidney when the patient was standing, and this may have been the cause of the hypertension.

Adult↗

PubMed1999

Colonic motility in children with repaired imperforate anus.

Following surgical correction of imperforate anus, voluntary bowel control is frequently poor because of abnormal anorectal function. Using colonic manometry we investigated the role of colonic motility in the pathogenesis of fecal soiling in children following imperforate anus repair. Thirteen children with repaired imperforate anus and fecal soiling underwent motility testing 2-12 years after anoplasty. All had fecal incontinence unresponsive to conventional medical treatment. Colonic manometry was performed using water-perfused catheters. Anorectal manometry was undertaken in 10 patients. Motility study results, treatment and outcomes were compared. All patients had high-amplitude propagating contractions (HAPCs) with an average of 80% propagation into the neorectum. There was no correlation between HAPC number or morphology and any variable. Internal anal sphincter resting pressure was low in 6/10 patients. Relaxation of the internal anal sphincter was present in 6/10 children. Only 1 of 5 patients able to cooperate was capable of generating a normal maximal squeeze pressure. Therapeutic regimens were changed in 11 patients with clinical improvement in five. Fecal soiling in patients with repaired imperforate anus is a multifactorial problem including propagation of excessive numbers of HAPCs into the neorectum as well as internal anal sphincter dysfunction. Colonic manometry in conjunction with anorectal manometry aids in the understanding of the pathophysiology of fecal soiling and guides clinical management in children with repaired imperforate anus.

Adolescent↗

PubMed1998

Bisacodyl and high-amplitude-propagating colonic contractions in children.

BACKGROUND: The purpose of these studies was to determine the suitability of bisacodyl for stimulating high-amplitude-propagating contractions in pediatric studies of colonic manometry. METHODS: Water-perfused manometry catheters were inserted into the right colon of children referred for evaluations related to defecation disorders. Colonic motility was measured in a 3-hour test session: an hour fasting, an hour after a meal, and 30 minutes after administration of a provocative agent. RESULTS: Bisacodyl was superior to edrophonium as a stimulant for inducing high-amplitude-propagating contractions. Bisacodyl-induced high-amplitude-propagating contractions were similar in amplitude, duration, propagation velocity, and sites of origin and extinction to naturally occurring high-amplitude-propagating contractions. The effect of intrarectal bisacodyl was similar to that of intracecal bisacodyl, except for a delay of 10 minutes in onset. Bisacodyl induced high-amplitude-propagating contractions in all 28 children (22 with spontaneous high-amplitude-propagating contractions) without evidence of neuromuscular disease and in 2 of 9 children with a colonic neuromuscular disorder and no spontaneous high-amplitude-propagating contractions. CONCLUSIONS: Bisacodyl-induced high-amplitude-propagating contractions were quantitatively and qualitatively similar to naturally occurring high-amplitude-propagating contractions. In selected cases, such as in children receiving total parenteral nutrition or restricted fluid intake, it may be possible to shorten diagnostic colonic manometry using bisacodyl rather than waiting for spontaneous high-amplitude-propagating contractions.

Adolescent↗

PubMed1997

Is electrogastrography a substitute for manometric studies in children with functional gastrointestinal disorders?

We performed simultaneous fasting and fed antroduodenal manometry and EGG in 25 children with functional bowel disorders. Three patients (12%) had an uninterpretable EGG. The manometric studies showed severe neuropathy in six patients; milder neuropathic changes in five patients; postprandial hypomotility in one patient; myopathy in four patients, and normal motility in the remaining six patients. The percentage of tachygastria time (frequency > 3.5 cycles/min) was higher in the patiens with mild (44.1 +/- 15.8%) and severe (48 +/- 19.1%) neuropathy than in the patients with myopathy (20 +/- 16.2%, P < 0.05) or with normal motility (23 +/- 13.3%, P < 0.05). There was a considerable overlap in the percentage of tachygastria and total arrhythmia time among the different study groups. The ratio of post- to preprandial power was significantly higher (2.5 +/- 0.07) in children with normal motility than in the other patients groups. Every child with total arrhythmia time < 35% and a ratio of post- to preprandial power > 2.4 had normal manometry. In summary, EGG differentiated groups of children with normal manometry from others with neuropathic or myopathic changes, but in a minority of patients the study was not interpretable and there was overlap in EGG results between children with normal and abnormal manometry.

Adolescent↗

PubMed1994

Role of spinal afferents and calcitonin gene-related peptide in the postoperative gastric ileus in anesthetized rats.

OBJECTIVE: The object of this study was to investigate the mechanisms of postoperative gastric ileus in an experimental model of abdominal surgery in anesthetized rats. SUMMARY BACKGROUND DATA: Sensory neurons partly mediate postoperative gastric ileus. Among other neuropeptides, sensory neurons contain calcitonin gene-related peptide (CGRP) and release CGRP in response to noxious stimulation. Because CGRP inhibits gastric motility, it was hypothesized that abdominal surgery stimulates sensory neurons, which then releases CGRP, thereby inhibiting gastric motility. METHODS: Postoperative ileus was induced by abdominal surgery. Gastric corpus motility was measured by an intragastric catheter. CGRP action was blocked by CGRP immunoneutralization or by a CGRP receptor antagonist. Spinal sensory neurons were ablated by application of a sensory neurotoxin (capsaicin) to the celiac and superior mesenteric ganglia. RESULTS: Abdominal surgery decreased gastric corpus motility in the first 5 minutes after abdominal surgery by 59 +/- 5% and by 24 +/- 4% during the 1st postoperative hour. Capsaicin pretreatment of the celiac and superior mesenteric ganglia, CGRP immunoneutralization, or CGRP receptor antagonism reversed the postoperative decrease in gastric corpus motility during the 1st postoperative hour by 50%, 100%, and 59%, respectively. CONCLUSIONS: These data indicate that spinal sensory neurons and CGRP partly mediate postoperative gastric ileus. CGRP may be released from spinal sensory neuron terminals in the celiac and superior mesenteric ganglia as part of an extraspinal intestinogastric inhibitory reflex activated by abdominal surgery.

Abdomen↗

PubMed1993

Colonic manometry in children with chronic intestinal pseudo-obstruction.

Pressure changes were evaluated in the transverse, descending, and rectosigmoid colon of 30 children with chronic intestinal pseudo-obstruction. Twenty two had severe lifelong constipation and eight had symptoms suggesting a motility disorder exclusively of the upper gastrointestinal tract. Based on prior antroduodenal manometry, 24 children were diagnosed as having a neuropathic and six a myopathic form of intestinal pseudo-obstruction. On the day of study, endoscopy was used to place a manometry catheter into the transverse colon and intraluminal pressure was recorded for more than four hours. After a baseline recording, we gave a meal to assess the gastrocolonic response. Colonic contractions were noted in 24 children. The six children with no colonic contractions had a hollow visceral myopathy and constipation. In the children with colonic contractions, fasting motility did not differentiate children with and without constipation. After the meal, in all eight children without constipation there was (1) an increase in motility index (3.2 (SEM 0.3) mm Hg/min basal v 8.4 (SEM 1.1) mm Hg/min postprandial; p < 0.001), and (2) at least one high amplitude propagated contraction (HAPC). In the 16 constipated children with colonic contractions the motility index did not significantly increase after the meal (2.1 (SEM 0.3) mm Hg/min basal v 3.1 (SEM 0.4) mm Hg/min postprandial) and 12 of them had no HAPCs (p < 0.01 v group without constipation). In summary, in children with a clinical diagnosis of chronic intestinal pseudo-obstruction, constipation is associated with absence of HAPCs, and the gastrocolonic response or with total absence of colonic contractions. It is concluded that studies of colonic manometry are feasible in children and may document discrete abnormalities in those with intestinal pseudo-obstruction with colonic involvement.

Child↗

PubMed1992

Use of colonic manometry to differentiate causes of intractable constipation in children.

We evaluated colon manometry as a means of differentiating causes of intractable constipation in children. We studied pressure changes in the transverse, descending, and rectosigmoid colons of 23 children with intractable constipation. All patients had a history of less than one bowel movement per week for longer than 2 years without resolution after conventional medical management. The possibility of Hirschsprung disease was excluded in all. On the basis of pathologic and manometric studies of the upper gastrointestinal tract, 10 patients had a diagnosis of gastrointestinal neuropathy and two had a diagnosis of myopathy. The other 11 patients had functional fecal retention; this diagnosis was based on history and outcome of therapy. On the day of study we used endoscopy to place a manometry catheter into the transverse colon and recorded intraluminal pressure for longer than 4 hours. After obtaining a baseline recording, we gave the patient a meal to assess gastrocolonic response. Colonic contractions were recorded in 21 of 23 children. Children with functional fecal retention could be differentiated from those with neuropathy by examination of the postprandial record. After a meal children with functional fecal retention had (1) an increase in motility index (3.4 +/- 0.5 while fasting vs 9.1 +/- 1.3 postprandially; p less than 0.001), and (2) at least one high-amplitude propagated contraction (in 10 of 11 children). The patients with neuropathy had no high-amplitude propagated contractions (p less than 0.001 vs group with functional fecal retention) and motility index in these children did not increase significantly after a meal (2.7 +/- 1.0 while fasting vs 2.9 +/- 1.3 postprandially). The two children with hollow visceral myopathy had no contractions. We conclude that in children with severe chronic constipation the colonic results of manometry differentiate patients with functional fecal retention from those with neuropathy or myopathy of the colon.

Child↗

PubMed1992

An abnormal rate of actin myosin cross-bridge cycling in colonic smooth muscle associated with experimental colitis.

Previous studies showed that colonic smooth muscle develops less contractile force to neurohumoral stimulation when associated with mucosal inflammation. This study evaluated 1) the Ca2+ dependence for colonic smooth muscle contraction, 2) the maximum velocity of muscle shortening (Vmax), and 3) changes in 20-kDa myosin light-chain (MLC) phosphorylation in distal circular colonic muscle from healthy rabbits and from rabbits with experimental colitis, induced by Formalin and immune complexes. The isometric tension of unskinned muscle stimulated with bethanechol or KCl was less (P less than 0.05) in animals with colitis compared with the control group. In saponin-skinned muscle, the amplitude of the maximal tension at [Ca2+] of 3 x 10(-7) M was decreased (P less than 0.05) in colitis animals (4.3 +/- 0.9 x 10(4) N/m2, n = 7) compared with healthy animals (10.5 +/- 2.4 x 10(4) N/m2, n = 6). However, the ED50 for Ca2+ stimulation was similar (P greater than 0.05) in both groups. When MLC was thiophosphorylated with ATP gamma S, the tension development was decreased in colitis (2.1 +/- 0.3 x 10(4) N/m2, n = 5; P less than 0.01) compared with normals (5.0 +/- 1.4 x 10(4) N/m2, n = 5). In healthy animals, phosphorylation of 20-kDa MLC increased rapidly to 51.2 +/- 3.1% within 15 s after stimulation and subsequently declined to 19.0 +/- 2.1% at 5 min. Vmax was maximal (0.14 Lo/s) 13 s after stimulation and declined before maximal active isometric stress. In colitis animals, the 20-kDa MLC phosphorylation (P less than 0.05) and the Vmax (P less than 0.01) were decreased.(ABSTRACT TRUNCATED AT 250 WORDS)

Actins↗

PubMed1991

Colonic motility and transit in health and ulcerative colitis.

Preprandial and postprandial colonic motility and transit (scintigraphy), with respect to the splenic flexure, were studied in 10 patients with ulcerative colitis and in 9 healthy subjects. The healthy subjects had a postprandial increase in intraluminal pressure that was significantly (P less than 0.03) greater in the descending colon than in other regions of the colon. In ulcerative colitis, the pressure was decreased in all regions compared with healthy subjects, with no significant pressure gradient among different regions. In normal subjects, transit was quiescent during fasting; eating stimulated both antegrade and retrograde transit. In ulcerative colitis, transit was variable before as well as after the meal. Both healthy subjects and patients with ulcerative colitis had more rapid emptying from the splenic flexure into the sigmoid than into the transverse colon. More frequent, low-amplitude, postprandial propagating contractions occurred in ulcerative colitis (P less than 0.05) than in healthy subjects. Propagating contractions were always antegrade and caused a rapid movement of the tracer into the sigmoid. In conclusion, ulcerative colitis is characterized by (a) decreased contractility, (b) increased low-amplitude propagating contractions, and (c) variable transit. These disturbances may accentuate the diarrhea in ulcerative colitis.

Adult↗

PubMed1991

Effect of eating on colonic motility and transit in patients with functional diarrhea. Simultaneous scintigraphic and manometric evaluations.

The aim of this study was to correlate colonic motility with transit in 8 patients with functional diarrhea compared to 12 healthy subjects. Intraluminal pressure was measured with perfused catheter ports in the transverse colon, splenic flexure, and descending and sigmoid colons. Transit of the luminal contents was measured by following the movement of 99mTC-diethylenetriaminepentaacetic acid instilled as a bolus in the splenic flexure. In patients with diarrhea, the intraluminal marker moved in and out of the transverse and sigmoid colon regions of interest during fasting, unlike healthy subjects, in whom the marker remained in the splenic flexure. After eating, radioactivity immediately increased in both the transverse and sigmoid colons in healthy subjects. In the patients with diarrhea, eating did not alter the marker movement into the different regions of the colon compared with fasting. Within 100 minutes of eating, the intraluminal marker almost disappeared from the regions of interest in patients with diarrhea. Postprandial colonic nonpropagating contractions increased in each region of the colon in healthy subjects; there was only a small postprandial increase in colonic motility in patients with diarrhea. However, the numbers of fasting and postprandial propagating contractions were increased in patients with diarrhea compared with healthy subjects (P less than 0.02). Each propagating contraction moved more tracer in patients with diarrhea than in healthy subjects (P less than 0.05). These studies suggest that (a) in patients with diarrhea, the fluctuation of marker in both transverse and sigmoid colons during the fasting and postprandial periods is associated with decreased nonsegmenting contractions and frequent propagating contractions; and (b) in healthy subjects, the intraluminal marker moved after eating because of a pressure gradient caused by nonpropagating contractions.

Adult↗

PubMed1991

Cisapride in children with chronic intestinal pseudoobstruction. An acute, double-blind, crossover, placebo-controlled trial.

To assess the effect of cisapride on gastrointestinal motility and gastric emptying in children with chronic intestinal pseudoobstruction, 20 children (mean age, 4.9 years; 14 female and 6 male) who required special means of alimentation or who had severe symptoms confirmed by diary during 2 weeks before the study were studied. A motility catheter with recording sites in the antrum and duodenum was placed on the first day of the study and remained in place until the end of the 5-day study. Cisapride (0.3 mg/kg PO t.i.d.) or placebo was given in double-blind randomized crossover fashion, with a 2-day "washout" interval. Antroduodenal motility was recorded on days 2 and 5. Recording consisted of 4 hours of fasting and 2 hours after a complex liquid meal labeled with 99mTc. Gastric emptying was assessed for 1 hour after the meal. Based on manometry, 16 patients had neuropathic and 4 patients had myopathic disorders. Cisapride had no effect on the discrete, qualitative abnormalities found in individual records. Cisapride increased the postprandial duodenal motility index from 1180 +/- 256 mm Hg/30 min after placebo to 2385 +/- 430 mm Hg/30 min (P less than 0.05) but had no significant effect on the antral motility index. Cisapride did not alter the profound delay in gastric emptying; time to reach 50% of initial activity (T1/2) was 105 +/- 20 vs. 93 +/- 19 minutes and percentage of retention after 60 minutes (R60) 56% +/- 4% vs. 58% +/- 4% in control vs. cisapride, respectively. In summary, in children with chronic intestinal pseudoobstruction, cisapride increased postprandial duodenal motility but did not improve gastric emptying.

Child↗

PubMed1990

Postprandial colonic transit and motor activity in chronic constipation.

The aim of this study was to correlate colonic motility and transit in patients with constipation and symptoms of the irritable bowel syndrome. Studies were performed in 16 patients with constipation and compared with the results in 12 healthy subjects. Intraluminal pressure was measured with perfused catheter ports in the transverse colon, splenic flexure, and descending and sigmoid colon. Movement of the luminal contents was measured by following the movement of Technetium-99m-DTPA that was instilled as a bolus in the splenic flexure. In both healthy subjects and patients with constipation there was no movement of the intraluminal tracer and no increase in intraluminal pressure during fasting. After eating a meal, healthy subjects and one group of the constipated patients had an increase in the radioactive marker in the transverse colon (p less than 0.03) and in the sigmoid colon (p less than 0.03). The movement of the intraluminal contents was associated with a positive pressure gradient between the descending colon and the transverse and sigmoid colon. There was no retrograde movement of the intraluminal contents and no postprandial increase in intraluminal pressure in the second group of patients with constipation. In healthy subjects, propagating contractions, which were associated with the rapid movement of intraluminal contents, began 60 min after eating. There were no propagating contractions in patients with constipation. These studies suggest that (a) the movement of intraluminal contents in healthy and constipated patients is determined by the postprandial pressure gradients within the colon, and (b) the propagating contraction is necessary for a normal bowel habit.

Adult↗

PubMed1990

Effect of dietary fiber on symptoms and rectosigmoid motility in patients with irritable bowel syndrome. A controlled, crossover study.

The aims of this study were to determine (a) whether dietary fiber supplements modify symptoms in patients with irritable bowel syndrome, (b) the effect of fiber on rectosigmoid pressures, and (c) the relationship, if any, between rectosigmoid pressure and symptoms. Fourteen patients entered and 9 completed a double-blind, controlled, cross-over study of 7 mo duration. The mean age was 26 yr (range, 18-37). Patients received 4 cookies daily containing 20 mg corn fiber or placebo. Symptoms and compliance were evaluated monthly. Rectosigmoid pressures and dietary intake were evaluated at the outset and completion of each study arm. Symptoms improved during both fiber and placebo treatments. Those symptoms demonstrating significant improvement with time were pain severity, stool frequency, stool consistency (p = 0.001), number of additional gastrointestinal symptoms present (p = 0.02), and total symptom score (p less than 0.001). Rectosigmoid pressures were not significantly altered by fiber or placebo. Fasting pressures at the distal recording site tended to correlate with pain severity (r = 0.6; p = 0.06). It was concluded that (a) corn fiber and placebo were both effective in alleviating symptoms, (b) there was a correlation between symptom severity and fasting rectosigmoid pressure, and (c) there was a trend toward reduction in fasting and postprandial rectosigmoid pressures after fiber therapy.

Adult↗

PubMed1990

Neural control of duodenal motor inhibition by antral contractions in dogs.

The mechanism of the inhibition of proximal duodenal motor activity by carbachol-induced antral contractions or by field stimulation was studied in anesthetized dogs that had strain gauges sutured 5 and 10 cm from the pylorus on the antrum and duodenum. The duodenum was excited by vagal stimulation or distal duodenal field stimulation. Duodenal inhibition was studied 1) during a control period and after the pylorus was transected followed by administration of phentolamine, 2) during control and after phentolamine followed by pyloric transection, 3) during control and after prazosin followed by yohimbine, and 4) during control and after yohimbine. Duodenal inhibition was greater when the antral stimulation or duodenal contractions were near the pylorus. Pyloric transection did not significantly reduce this inhibition; phentolamine then abolished it. Prazosin did not abolish inhibition but yohimbine did. In conclusion, antroduodenal inhibition under our experimental conditions was mediated primarily by sympathetic nerves modulating the activity of duodenal cholinergic nerves, which possess alpha 2-adrenoceptors, and to a less extent by intrinsic nerves crossing the pylorus.

Animals↗

PubMed1990

Antroduodenal manometry in the evaluation of chronic functional gastrointestinal symptoms.

Intraluminal pressure in the gastric antrum and duodenum was studied in 44 children and adolescents referred for evaluation because of functional symptoms, including vomiting, abdominal distension, and abdominal pain. Manometric abnormalities were found in 39 patients (89%). Abnormalities during fasting included absence of the migrating motor complex; retrograde, phase 3-like episodes; increased frequency, decreased duration, and decreased amplitude of phase 3 episodes; tonic duodenal contractions; nonpropagated bursts of duodenal contractions; and consistently low-amplitude or absent contractions. Postprandial abnormalities included a phase 1-like pattern (postprandial hypomotility) and phase 3-like episodes (failure to induce a fed pattern). The presence or absence of the migrating motor complex was a predictor of disability. Parenteral alimentation was needed by only 4 of 28 patients with the migrating motor complex, but by 13 of 16 patients without the migrating motor complex (P less than .001). In 15 of 18 patients studied on consecutive days, oral cisapride was associated with increases in the number and amplitude of duodenal contractions after a complex-liquid meal (P less than .02). It is concluded that antroduodenal manometry is a useful technique that elucidates the underlying gastrointestinal motility disorder present in the majority of children and adolescents with severe functional symptoms.

Adolescent↗

PubMed1989

Association between postprandial changes in colonic intraluminal pressure and transit.

The aim of this study was to correlate the movement of colonic luminal contents with the changes in intraluminal pressure. Studies were performed in 9 healthy volunteers. Intraluminal pressure was measured with perfused catheter ports in the transverse, splenic flexure, descending, and sigmoid colon. Movement of the luminal contents was measured by following the movement of technetium 99m-ethylenetriamine-pentaacetic acid that was instilled as a bolus in the splenic flexure. During fasting there was very little change in pressure or in the movement of intraluminal contents. After eating a 1000-kcal meal, the tracer moved from the splenic flexure into the transverse colon and the sigmoid colon. Nonpropagating colonic motor activity increased in all colonic segments immediately after eating the meal (p less than 0.05). The increase in motility was significantly greater in the descending colon than in the transverse and sigmoid colon (p less than 0.05). In one-half of the subjects propagating contractions occurred postprandially. The movement of the intraluminal tracer occurred during both types of motility. The nonpropagating contractions were associated with a gradual movement of the luminal contents. The direction of the movement of the contents was determined by the differences in pressure in the different segments of the colon. The propagating contractions were associated with a rapid movement of intraluminal contents. These studies suggest that (a) colonic motility and transit are quiescent during fasting and (b) the transverse colon acts as a mixing and storage area, as retrograde transit into the transverse colon is the characteristic postprandial pattern.

Adult↗