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Biomedical subjects

K A Kelly

Publications and source records attributed to K A Kelly.

At least 109 records · Page 6Linked to original sources
PubMed1991

The effect of peripheral immunization with Mls-1a on the emigration of antigen-specific cells from the thymus.

Mature T cells found in the lymph nodes and spleen have the capacity to become activated and to proliferate in response to foreign antigens. The response of the thymus to such immunization is less well understood. We have examined one aspect of the thymic response by determining the effect of peripheral immunization upon cell emigration from the thymus. BALB/c (Mls-1b) mice were injected with spleen cells from DBA/2 (Mls-1a) mice, and V beta 6+ (Mls-1a-reactive) thymic emigrants were identified 3-30 days after immunization. Neither the rate of total cell migration from the thymus nor the proportion of V beta 6+ cells was altered, even though the immunizing spleen cells elicited an immune response in the draining (parathymic) lymph nodes. The same immunogen caused deletion of V beta 6+ cells in both the thymus and lymph nodes after intraperitoneal injection into the neonate. The inability of DBA/2 splenocytes to modify the development of adult thymocytes after intrathymic injection of the cells precluded the lack of entry into the thymus as the reason for the lack of any observed effect in the adult. Our results, therefore, indicate that the development of adult thymocytes is not modified by immunization, and suggest that the differing thymic response of mice injected as adults or neonates is related to changes in the intrathymic antigen presentation capacity associated with age.

Age Factors↗
PubMed1991

Response of canine ileocolonic sphincter to intraluminal acetic acid and colonic distension.

The aim was to determine the effect of intraluminal acetic acid and proximal colonic distension on canine ileocolonic sphincter pressure, ileal motility, and coloileal reflux. In six conscious dogs with an isolated ileocolonic loop, basal pressure of the ileocolonic sphincter was similar during ileal perfusion with 100 mM acetic acid at 1 ml/min (mean +/- SEM = 18 +/- 0.4 mm Hg) and with saline (18 +/- 0.5 mm Hg; P = 0.81). Discrete clustered ileal contractions were more frequent with acetic acid, however, and when they propagated across the sphincter, sphincter pressure increased from 18 +/- 0.4 mm Hg to 36 +/- 1.3 mm Hg (P = 0.002). Sphincter pressure was also greater during colonic perfusion with acetic acid (32 +/- 0.7 mm Hg) than during ileal perfusion with acetic acid or saline (P less than 0.017). Moreover, sphincter pressure gradually increased as the colon was distended with saline (slope = 0.8 mm Hg/cm H2O, P less than 0.017) or acetic acid (slope = 0.5 mm Hg/cm H2O, P less than 0.017), but the increase did not prevent coloileal reflux. In conclusion, ileal clustered contractions, colonic perfusion of acetic acid, and colonic distension all increased canine ileocolonic sphincter pressure.

Acetates↗
PubMed1991

Influence of in situ neural isolation of jejunoileum on postprandial pancreatobiliary secretion and gastric emptying.

Our aims were to examine the influence of neural isolation of the jejunoileum on postprandial pancreatobiliary secretion. In four dogs, duodenal perfusion and aspiration catheters were implanted, and serosal electrodes were placed along the proximal small bowel. Control studies of gastric emptying, output of bile acids and amylase, and plasma concentrations of peptide YY and neurotensin were performed on three occasions following ingestion of a 340-kcal mixed-nutrient liquid meal. The dogs then underwent our model of in situ jejunoileal neural isolation, and the meal studies were repeated. Neural isolation, when compared to control, did not affect either postprandial conversion of intestinal myoelectric activity to the "fed" pattern, gastric emptying (T1/2, X +/- SE of the liquid meal (74 +/- 6 vs 79 +/- 7 min; P greater than 0.05), or cumulative amylase output (373 +/- 59 vs 305 +/- 66 kU; P greater than 0.05). Neural isolation decreased cumulative postprandial bile acid output from 6.6 +/- 0.9 mM to 3.4 +/- 1.1 mM (P less than 0.05) and increased postprandial plasma concentrations of peptide YY and neurotensin. Our findings suggest that the jejunoileal denervation that accompanies the in situ neural isolation of the jejunoileum is not associated with changes in postprandial motility patterns, gastric emptying, or pancreatic amylase secretion. Loss of this innervation, however, may decrease postprandial output of bile acids and lead to a compensatory increase in the postprandial release of neurotensin and peptide YY.

Amylases↗
PubMed1991

Let sleeping dogs lie: role of the omentum in the ileal pouch-anal anastomosis procedure.

A surgical aphorism has long held that the omentum is the "watchdog of the abdomen." However, detractors believe that leaving the omentum behind after colectomy precipitates later small bowel obstruction. A retrospective comparison was made between a group of 406 patients (Group I) having omentectomy with proctocolectomy and ileoanal anastomosis and a group of 239 patients (Group II) having a similar procedure without omentectomy. Follow-up in this series of 645 patients was 4.3 +/- 2.1 years (mean +/- SEM). No difference was present in the rate of partial small bowel obstruction or complete small bowel obstruction between Group I patients (32 percent partial, 12 percent complete) and Group II patients (29 percent partial, 12 percent complete; P greater than 0.1). However, a better outcome with regard to postoperative sepsis and sepsis requiring operation was apparent in Group II patients retaining the omentum (4 percent and 3 percent, respectively) than in Group I patients (10 percent and 8 percent, respectively), in whom the omentum was removed (P less than 0.01). As this experience would support, we urge surgeons to "let sleeping dogs lie" and, when possible, retain the omentum when performing colectomy or proctocolectomy.

Adult↗
PubMed1991

Proximal gastric vagotomy in the emergency treatment of bleeding duodenal ulcer.

Proximal gastric vagotomy for bleeding duodenal ulcer was performed in 52 low-risk patients between 1973 and 1986. Duodenotomy without violation of the pylorus was done in all patients to allow inspection and control of the bleeding site. The median duration of operation was 3 hours and 20 minutes, although 25% of the procedures required 4 or more hours. There was no postoperative mortality and no early reoperations. Among the six patients with postoperative complications, one rebled from the ulcer and two developed prolonged gastric atony. At the time of follow-up (median, 2.9 years), 48 of the patients were alive and 4 had died of non-ulcer causes. No patient had significant postvagotomy sequelae. Ulcer recurrence was documented in six patients, and three required reoperation. Proximal gastric vagotomy is a safe, effective therapy for bleeding duodenal ulcer. Because of the length of the operation, it should be restricted to low-risk patients who are hemodynamically stable at the time of operation.

Adult↗
PubMed1991

The Roux operation for postgastrectomy syndromes.

The aim of this paper is to describe the technique, indications, and results of the Roux operation as used in the treatment of postgastrectomy syndromes. A Roux gastrojejunostomy with a 40-cm Roux limb is the procedure of choice for alkaline reflux gastritis, because it virtually eliminates reflux of bile and pancreatic juice into the stomach. The slow transit through a Roux limb can also be used to good advantage to slow gastric emptying in patients with dumping. Patients with delayed gastric emptying respond to the combination of near-total gastric resection, which removes the atonic gastric remnant and speeds emptying, and Roux-Y gastrojejunostomy, which prevents reflux esophagitis and provides a reservoir for ingesta in the upper gut. After all Roux operations, however, the Roux limb may slow emptying so much that pain, fullness, nausea, and food vomiting result, the so-called Roux stasis syndrome. Prevention of the Roux stasis syndrome with an "uncut" Roux limb and the treatment of the syndrome by using electrical pacing to suppress the ectopic pacemakers that emerge in the limb offer possible new solutions to this vexing problem.

Anastomosis, Roux-en-Y↗
PubMed1991

Human anal motility while fasting, after feeding, and during sleep.

The aim of this study was to determine whether the human anal sphincter responds dynamically to changing physiological states. In 19 healthy human subjects, intraluminal anal canal pressure was measured with a 5-cm perfused sleeve sensor during the day while fasting (3 hours) and after feeding (3 hours) and at night during sleep (8 hours). Daytime mean anal canal pressures (+/- SEM) while fasting (50 +/- 3 mm Hg) were similar to those after feeding (49 +/- 3 mm Hg) and to those at night during sleep (49 +/- 3 mm Hg). Marked minute-to-minute variations in mean pressure occurred in all three periods, however, as did large phasic increases and decreases in pressure (greater than 20 mm Hg) and small phasic changes in pressure less than 20 mm Hg (anal slow waves). The minute-to-minute variations in mean pressure were greater during the awake fed state (4 +/- 1 mm Hg/min) than at night during sleep (2 +/- 1 mm Hg/min; P less than 0.03), as were the number of large phasic waves per minute (increases in pressure: awake, fed = 0.5 +/- 1 waves/min, night = 0.3 +/- 0.1 waves/min, P less than 0.05; decreases in pressure: awake, fed = 0.4 +/- 0.1 waves/min, night = 0.2 +/- 0.1 waves/min, P less than 0.05). Anal small waves had a similar frequency of about 17 waves/min in all three states. In conclusion, the anal sphincter maintains a continuous pressure barrier to rectal outflow both during the day and at night during sleep. However, marked minute-to-minute variations in mean pressure and large phasic increases and decreases in pressure do occur. Both are fewer at night during sleep.

Adult↗
PubMed1991

SDS-soluble and peptidoglycan-bound proteins in the outer membrane-peptidoglycan complex of Brucella abortus.

Outer membrane-peptidoglycan complex from Brucella abortus was separated from cytoplasmic membrane and cytosol by either sucrose density gradient fractionation or differential (rate) centrifugation of surface labeled cells disrupted by sonication without the use of detergents. The outer membrane-peptidoglycan complex had a buoyant density of 1.22 gm/ml and contained 67 labeled SDS-soluble proteins when examined by SDS-PAGE. Included were four major bands exhibiting molecular masses of 88k, 40k, 35.7k and 26k daltons corresponding to previously described group 1, 2 and 3 outer membrane proteins. Lysozyme treatment of outer membrane-peptidoglycan complex increased its buoyant density to 1.25 gm/ml and released eight additional peptidoglycan-linked proteins.

Animals↗
PubMed1991

Prospective evaluation of vertical banded gastroplasty as the primary operation for morbid obesity.

Our previous experience with vertical (nonbanded) gastroplasty proved disappointing because of unsatisfactory maintenance of weight loss. Vertical banded gastroplasty seemed to be an attractive alternative operation because it provided an externally reinforced (banded) stoma that would not enlarge over time. In this study, our aim was to determine prospectively the results of vertical banded gastroplasty used as a primary, weight-reducing procedure in patients with morbid obesity. Seventy consecutive patients with morbid obesity (mean weight, 139 kg), all of whom had obesity-related complications, underwent vertical banded gastroplasty and prospective follow-up. The hospital mortality was nil, and substantial morbidity occurred in 3% (two patients). Long-term achievement and maintenance of satisfactory weight loss, however, were variable. The median weight loss at 1 year after operation was 36.7 kg or 48% of excess body weight. At 3 years postoperatively, however, weight loss was only 32.4 kg or 40% of excess body weight, and only 38% of patients had achieved and maintained a weight loss of 50% or more of their preoperative excess body weight. Vertical banded gastroplasty caused major changes in eating habits, and many patients were unable to eat red meat or untoasted bread; moreover, approximately 30 to 50% of patients continued to vomit once or more per week. Despite theoretically attractive advantages as a weight-reduction operation, vertical banded gastroplasty does not seem to be the optimal procedure for most patients with morbid obesity.

Adult↗
PubMed1991

Neo-adjuvant (pre-emptive) cisplatin therapy in invasive transitional cell carcinoma of the bladder.

Following 2 pilot studies which showed 57 and 61% response rates to intravenous cisplatin for transitional cell carcinoma of the bladder prior to definitive treatment, the West Midlands Urological Research Group (WMURG) and the Australian Bladder Cancer Study Group (ABCSG) independently began randomised trials to test the survival benefit of neo-adjuvant intravenous cisplatin prior to radiotherapy in T2-T4 M0 transitional cell carcinoma of the bladder. Both trials failed to recruit their target numbers of 250 patients in the West Midlands and 320 in Australia. Since they had similar treatment protocols and eligibility criteria, they were combined in an overview analysis, achieving a total number of 255 patients. Each treatment group was compared with its own control group and the differences were pooled to give an overall result. There was no difference in survival between treated and control patients. The odds ratio was 1.13 with the control groups faring marginally better than the chemotherapy groups. Even with 255 patients the 95% confidence interval of the odds ratio was wide (0.80-1.57). Although there is no clear evidence of a clinically worthwhile benefit from neo-adjuvant cisplatin, this approach must be tested in a larger study using combination treatments with greater activity in metastatic disease.

Aged↗
PubMed1991

Quality of life after proctocolectomy. A comparison of Brooke ileostomy, Kock pouch, and ileal pouch-anal anastomosis.

Recent work has shown that patients undergoing proctocolectomy and ileal pouch-anal anastomosis experience a better quality of life than those undergoing proctocolectomy and Brooke ileostomy. To assess whether the improvement with the pouch is due to the absence of a stoma or the preservation of fecal continence, functional and performance activities were assessed in 406 patients with Brooke ileostomies (stoma present, incontinent), 313 with Kock pouches (stoma present, continent), and 298 with ileal pouch-anal anastomoses (stoma absent, continent). All patients underwent proctocolectomy for ulcerative colitis or familial adenomatous polyposis. After adjusting for age, sex, diagnosis, attitude towards the operation, dietary satisfaction, and ability to work, the likelihood of an impact on performance was estimated for the three types of operation using logistic regression analysis. Patients with ileal pouch-anal anastomoses had fewer restrictions in sports and sexual activities than those with Kock pouches (P less than 0.05), whereas those with Kock pouches in turn had fewer restrictions in these activities but more restrictions in travel than those with Brooke ileostomies (P less than 0.05). In contrast, performance in the categories of social life, recreation, work, and family was similar between groups. It is concluded that both the presence of a stoma and fecal incontinence impair the quality of life after proctocolectomy. Ileal pouch-anal anastomosis, which avoids both stoma and incontinence, offers the best quality of life between the three operations studied.

Adenomatous Polyposis Coli↗
PubMed1991

Factors affecting the diameters of the common bile duct and pancreatic duct using endoscopic retrograde cholangiopancreatography.

Endoscopic retrograde cholangiopancreatography (ERCP) findings in 405 patients were analyzed to compare common bile duct (CBD) and main pancreatic duct (PD) diameters in relation to age, sex, gallbladder stones, CBD stones and acute pancreatitis. There were 129 patients with gallstones uncomplicated by pancreatitis, 131 patients with pancreatitis, and 145 control subjects. Significant correlations were found between CBD and PD diameters, and between these and age. Independently significant determinants of the CBD diameter were age, female, sex, CBD stones and gallbladder stones, as well as PD diameter. Conversely, PD diameter was significantly dependent upon age, CBD diameter, and acute pancreatitis. This study suggests that both CBD and PD dilation occurs in patients with gallstone disease. In view of the different factors which affect CBD and PD diameters (particularly age), important clinical decisions previously recommended on the basis of these duct diameters may need to be qualified.

Acute Disease↗
PubMed1990

Effects of light treatment on core body temperature in seasonal affective disorder.

Abnormalities in circadian rhythms of core body temperature have been reported previously in depressed patients. In this study, we compared the temperature rhythms of 10 depressed seasonal affective disorder (SAD) patients with winter depression with those of 12 normal controls and evaluated the effects of bright light on temperature in SAD. Unlike previous studies of depressed patients, the temperature curves of the patients and normal controls during the off-light condition were nearly identical. We found a significant difference in amplitude between the patients in the untreated and light-treated conditions. Although there was no systematic difference in circadian phase across groups or treatment conditions, we present preliminary evidence that suggests that phase-typed subgroups may be present in the population distinguished by their treatment responses.

Adult↗
PubMed1990

Absorption and motility of the bypassed human ileum.

The authors assessed absorption and motility of the human ileum after a prolonged period of disuse. In eight patients with ulcerative colitis, a manometric-catheter assembly was placed via the ileostomy into the unused portion of distal ileum two months after ileal pouch-anal anastomosis and temporary diverting loop ileostomy. The distal ileum was perfused at 5 ml/min with an isosmotic solution of either sodium chloride or ileal chyme diluted with sodium chloride for three hours before and three hours after a meal on two consecutive days. Absorption was measured, single and clustered pressure waves were identified and quantitated with the aid of a computer program, and a motility index was calculated. Mean absorption +/- S.E.M. of both perfusates was poor on day 1 (-10 +/- 2 ml/25 cm x 30 min), and the meal induced no ileal motor response. By day 2, however, absorption of both perfusates was much improved (-1 +/- 2 ml/25 cm x 30 min; P less than 0.05), and the number of discrete clustered contractions and the motility index now clearly increased after the meal (2.6 +/- 0.6 vs. 7.2 +/- 1.0 clustered waves/hr; 7.5 +/- 0.5 vs. 9.7 +/- 0.2 motility units/30 min; P less than 0.05). The conclusion was that absorption and motility of the human ileum were impaired after two months of disuse, but that ileal absorption and motility improved one day after the introduction of isosmotic ileal perfusates.

Adult↗
PubMed1990

The 'ileal brake' after ileal pouch-anal anastomosis.

The aim of this study was to assess if infusion of oleic acid into the ileal pouch would slow gastric emptying and small-bowel transit, delay defecation, and increase plasma levels of enteroglucagon, neurotensin, or peptide YY in patients with colectomy and ileal pouch-anal anastomosis. Eight subjects with chronic ulcerative colitis who had undergone the operation were studied on 2 consecutive days. On 1 day, saline (154 mM NaCl) was infused into the ileal pouch, and on the other day emulsified oleic acid (152 mM) was infused. The subjects ate a 300-kcal mixed meal containing liquid labelled with 99mTc-DTPA. To assess small-bowel transit concurrently with gastric emptying, a second marker, 111In-DTPA, was instilled through a tube into the duodenum at the end of the meal. Transit of both markers was monitored scintigraphically. Infusion of oleic acid into the ileal pouch slowed gastric emptying and small-bowel transit, and delayed the time to defecation compared with saline infusion. Neither the ileal pouch infusion alone or the meal alone altered plasma levels of enteroglucagon, neurotensin, or peptide YY, but the combination of the oleic acid infusion and the meal increased the levels of all 3 hormones. It was concluded that an "ileal brake" on gastrointestinal transit is functional following ileal pouch-anal anastomosis. Oleic acid placed into the ileal pouch slowed gastrointestinal transit and delayed defecation, effects which may have clinical application. The mechanism mediating the ileal brake may in part be hormonal.

Adult↗
PubMed1990

Electrical dysrhythmias in the Roux jejunal limb: cause and treatment.

Electrical dysrhythmias in the Roux limb after Roux gastrojejunostomy are associated with upper gut stasis of food. The aim of this study was to determine the cause of the dysrhythmias and whether they could be eliminated with pacing. A set of four dogs (Group A) underwent three sequential operations: placement of jejunal electrodes at sites corresponding to the Roux limb; construction of a Roux limb without vagotomy, gastrectomy, or gastrojejunostomy; and transthoracic truncal vagotomy. A second set of five dogs (Group B) underwent truncal vagotomy, distal gastrectomy, and Roux gastrojejunostomy with recording electrodes placed on the Roux limb and a pacing electrode situated at the proximal end of the limb. Electrical recordings were obtained on four separate occasions after each operation. In Group A dogs, orad and disordered propagation of jejunal pacesetter potentials occurred in the Roux limb 56 +/- 5% of the time after limb construction but never before construction. The pattern was not changed with vagotomy. In Group B dogs, electrical dysrhythmias in the Roux limb also occurred and were corrected with electrical pacing. We concluded that electrical dysrhythmias in the canine Roux limb are secondary to the jejunal transection done during Roux limb construction, and are not due to gastrectomy, gastroenterostomy, or vagotomy. The dysrhythmias can be corrected with pacing.

Anastomosis, Roux-en-Y↗