Biomedical subjects

Theodore N Pappas

Publications and source records attributed to Theodore N Pappas.

At least 19 recordsLinked to original sources

PubMed2006

Restraint stress stimulates colonic motility via central corticotropin-releasing factor and peripheral 5-HT3 receptors in conscious rats.

Although restraint stress accelerates colonic transit via a central corticotropin-releasing factor (CRF), the precise mechanism still remains unclear. We tested the hypothesis that restraint stress and central CRF stimulate colonic motility and transit via a vagal pathway and 5-HT(3) receptors of the proximal colon in rats. (51)Cr was injected via the catheter positioned in the proximal colon to measure colonic transit. The rats were subjected to a restraint stress for 90 min or received intracisternal injection of CRF. Ninety minutes after the administration of (51)Cr, the entire colon was removed, and the geometric center (GC) was calculated. Four force transducers were sutured on the proximal, mid, and distal colon to record colonic motility. Restraint stress accelerated colonic transit (GC of 6.7 +/- 0.4, n=6) compared with nonrestraint controls (GC of 5.1 +/- 0.2, n=6). Intracisternal injection of CRF (1.0 microg) also accelerated colonic transit (GC of 7.0 +/- 0.2, n=6) compared with saline-injected group (GC of 4.6 +/- 0.5, n=6). Restraint stress-induced acceleration of colonic transit was reduced by perivagal capsaicin treatment. Intracisternal injection of CRF antagonists (10 microg astressin) abolished restraint stress-induced acceleration of colonic transit. Stimulated colonic transit and motility induced by restraint stress and CRF were significantly reduced by the intraluminal administration of 5-HT(3) antagonist ondansetron (5 x 10(-6) M; 1 ml) into the proximal colon. Restraint stress and intracisternal injection of CRF significantly increased the luminal content of 5-HT of the proximal colon. It is suggested that restraint stress stimulates colonic motility via central CRF and peripheral 5-HT(3) receptors in conscious rats.

Animals↗

PubMed2006

Evaluation of preoperative therapy for pancreatic cancer using a prognostic nomogram.

BACKGROUND: Theoretical benefits of preoperative chemoradiation therapy (preop CRT) for pancreatic cancer include improved efficacy, resectability, and patient selection. The goal of this study was to evaluate the applicability of a nomogram, which was developed for patients undergoing resection without preop CRT and which incorporates several post-resection pathological factors, to a population of patients who received preop CRT prior to resection. METHODS: From 1994 to 2004, 82 patients with biopsy-proven, radiographically localized adenocarcinoma of the pancreatic head underwent preop CRT followed by pancreaticoduodenectomy (PD); 50 concurrent patients underwent PD without preop CRT. Mean nomogram-predicted disease-specific survival (DSS) rates were compared with observed DSS rates from the time of resection. RESULTS: Despite having more locally advanced tumors on initial staging (21 vs. 8%; P < .05), patients who received preop CRT had smaller resected tumors (mean 2.3 vs. 3.1 cm; P < .01), were less likely to have T3 tumors (54 vs. 80%, P < .01), were less likely to have positive lymph nodes (29 vs. 58%, P < .01), and had fewer positive lymph nodes (mean .4 vs. 1.9, P < .01), all factors that imply treatment effect and favorably impact on nomogram-predicted DSS. Observed DSS was similar to predicted DSS in both groups. CONCLUSIONS: The similarity in observed and predicted DSS following resection in patients who received preop CRT suggests that the effects of preop CRT-whether treatment, selection, or no effect-are reflected by the nomogram. The ability of the nomogram to evaluate the effects of preop CRT on survival is limited by the potential effects of preop CRT on factors within the nomogram.

Adenocarcinoma↗

PubMed2006

Glucagon like peptide-1 accelerates colonic transit via central CRF and peripheral vagal pathways in conscious rats.

Glucagon like peptide-1 (7-36) (GLP-1), one of the gastrointestinal (GI) regulatory peptide, is known to act as a stress related brain neurotransmitter mediating GI function. Central administration of GLP-1 inhibits gastric emptying. However, little is known about the effect of central GLP-1 on colonic transit. Effects and mechanism of GLP-1 on colonic transit were investigated in conscious rats. Immediately after intracerebroventricular (icv)-injection of GLP-1, 51Cr was applied via the catheter positioned to the proximal colon. 90 min after 51Cr injection, rats were euthanized and the colon was removed and divided into 10 equal segments. The radioactivity of each segment was counted and the geometric center (GC) was calculated. Icv-injection of GLP-1 (0.3-3 nmol) dose-dependently accelerated colonic transit [(GC: 4.4+/-0.2 in controls, 7.8+/-0.5 in GLP-1 (3 nmol)]. In contrast, intraperitoneal (ip)-injection of GLP-1 (3 nmol) did not modify colonic transit. Icv-injection of GLP-1 (3 nmol)-induced acceleration of colonic transit was attenuated by vagotomy, atropine and hexamethonium, but not by guanethidine. Icv-injection of GLP-1 (3 nmol)-induced acceleration of colonic transit was abolished by corticotropin releasing factor (CRF) antagonist, astressin. Restraint stress-induced acceleration of colonic transit was abolished by a selective GLP-1 receptor antagonist, exendin. These results indicate that the endogenous GLP-1 is involved in mediating stress-induced alteration of colonic transit via a central CRF and peripheral cholinergic pathways in rats.

Analysis of Variance↗

PubMed2006

Central glucagon like peptide-1 delays solid gastric emptying via central CRF and peripheral sympathetic pathway in rats.

It has been shown that glucagon like peptide-1 (GLP-1) acts on the central nervous system (CNS), in addition to its peripheral actions. Central administration of glucagon like peptide-1 (GLP-1) delays liquid gastric emptying via non-adrenergic, non-cholinergic neurons in rats. However, it remains unclear how central GLP-1 delays solid gastric emptying in rats. GLP-1 receptors at the CNS mediates the endocrine and anxiety responses to psychogenic and interoceptive stress. Corticotropin-releasing factor (CRF) is also known as a stress-related peptide, which delays gastric emptying of liquid and solid food via the autonomic nervous system. We have recently showed that central CRF delays solid gastric emptying via sympathetic pathways in rats. However, it remains unknown how central GLP-1 and CRF interact in mediating the inhibitory effect on solid gastric emptying. After a 24 h-fasting, GLP-1 was administered by intracisternal (ic)-injection immediately after the solid meal ingestion. Ninety minutes after the peptide injection, gastric contents were measured. Ic-injection of GLP-1 (30-3000 pmol) dose-dependently inhibited solid gastric emptying. Ic-injection of GLP-1 (3000 pmol)-induced delay of gastric emptying was partially antagonized by celiac ganglionectomy but not by atropine or N(G)-nitro-l-arginine methyl ester (L-NAME). Ic-injection of a CRF antagonist, astressin (2.8 nmol), partially antagonized GLP-1-induced delay of solid gastric emptying. These results indicate that central CRF and peripheral sympathetic pathway are, at least in part, involved in mediating central GLP-1-induced delay of solid gastric emptying in rats.

Animals↗

PubMed2006

Electroacupuncture elicits dual effects: stimulation of delayed gastric emptying and inhibition of accelerated colonic transit induced by restraint stress in rats.

Acupuncture has been used for treating functional gastrointestinal (GI) disorders. Animal studies have demonstrated that acupuncture antagonized various stress-induced responses. We investigated the effects of electroacupuncture (EA) at ST-36 (Zusanli; lower limb) on stress-induced alteration of GI motor activities. Solid gastric emptying was significantly delayed by restraint stress (29.6+/-2.4%; n=7) compared to that of controls (60.0+/-2.5%; n=8). Delayed gastric emptying was significantly improved by EA at ST-36 (47.2+/-1.8%). Intracisternal (IC) injection of corticotropin releasing factor (CRF; 1 microg) delayed gastric emptying to 25.4+/-3.1%, which was also improved by EA at ST-36, to 53.0+/-7.1% (n=8). The stimulatory effect of EA on stress-induced delayed gastric emptying was abolished by atropine (17.6+/-1.9%) but not by guanethidine (42.2+/-2.3%). Colonic transit was significantly accelerated by restraint stress (GC=7.2+/-0.3; n=8) compared to that of controls (GC=5.2+/-0.2; n=8). Accelerated colonic transit was significantly reduced by EA at ST-36 (GC=4.9+/-0.3). IC injection of CRF accelerated colonic transit (GC=6.9+/-0.2), which was also normalized by EA at ST-36 (GC=4.7+/-0.2). The inhibitory effect of EA on stress-induced acceleration of colonic transit was not affected by guanethidine (GC=4.6+/-0.3). In conclusion, EA at ST-36 showed dual effects: stimulation of stress-induced delayed gastric emptying and inhibition of stress-induced acceleration of colonic transit. The stimulatory effect of EA on stress-induced delayed gastric emptying is mediated via cholinergic pathways. The inhibitory effect of EA on stress-induced acceleration of colonic transit is independent of the sympathetic pathway.

Animals↗

PubMed2006

The selective mu opioid receptor antagonist, alvimopan, improves delayed GI transit of postoperative ileus in rats.

Postoperative ileus (POI) is often exacerbated by opioid analgesic use during and following surgery, since mu opioid receptor activation results in a further delay of gastrointestinal (GI) transit. The effects of alvimopan, a novel, selective, and peripherally acting mu opioid receptor antagonist, and the reference compound methylnaltrexone, upon POI were investigated in rats. Under isoflurane anesthesia, POI was induced by laparotomy with intestinal manipulation. Immediately after the surgery, the rats received (51)Cr by gavage. Three hours after the surgery, the rats were sacrificed and GI transit was estimated using the geometric center (GC) of (51)Cr. Alvimopan (0.1-3 mg/kg) or methylnaltrexone (100 mg/kg) were administered by gavage either before or after the surgery, with or without morphine administration (1 mg/kg). GI transit was delayed by intestinal manipulation (GC = 2.92 +/- 0.17). Alvimopan (1 and 3 mg/kg) significantly reversed this delayed GI transit when administered 45 min prior to surgery. However, the effects of alvimopan were less pronounced when administered following surgery. Morphine administration further delayed GI transit induced by intestinal manipulation (GC = 1.97 +/- 0.11). Under these conditions, alvimopan (1 and 3 mg/kg) also significantly improved delayed GI transit when administered before surgery. Methylnaltrexone was inactive under all experimental conditions. These data suggest that mu opioid receptors play a role in the pathogenesis of POI, and that the clinical benefit reported to be afforded by alvimopan may be in part mediated via inhibition of an endogenous opioid release as well as blockade of the unwanted GI actions of analgesic agents.

Analgesics, Opioid↗

PubMed2006

Increased toxicity with gefitinib, capecitabine, and radiation therapy in pancreatic and rectal cancer: phase I trial results.

PURPOSE: Overexpression of epidermal growth factor receptor (EGFR) has been associated with aggressive tumor phenotypes, chemotherapy, and radiation resistance, as well as poor survival in preclinical and clinical models. The EGFR inhibitor gefitinib potentiates chemotherapy and radiation tumor cytotoxicity in preclinical models, including pancreatic and colorectal cancer. We initiated two phase I trials assessing the combination of gefitinib, capecitabine, and radiation in patients with localized pancreatic and rectal cancer. PATIENTS AND METHODS: Patients with pathologically confirmed adenocarcinoma of the pancreas and rectum were eligible. Pretreatment staging included computed tomography, endoscopic ultrasound, and surgical evaluation. Patients received 50.4 Gy of external-beam radiation therapy to the tumor in 28 fractions. Capecitabine and gefitinib were administered throughout the radiation course. Following completion, patients were restaged and considered for resection. Primary end points included determination of dose-limiting toxicity (DLT) and a phase II dose; secondary end points included determination of non-DLTs and preliminary radiographic and pathologic response rates. RESULTS: Ten patients were entered in the pancreatic study and six in the rectal study. DLT was seen in six of 10 patients in the pancreatic study and two of six patients in the rectal study. The primary DLT in both studies was diarrhea. Two patients developed arterial thrombi. CONCLUSION: The combination of gefitinib, capecitabine, and radiation in pancreatic and rectal cancer patients resulted in significant toxicity. A recommended phase II dose was not determined in either of our studies. Further investigation with this combination should be approached with caution.

Adenocarcinoma↗

PubMed2006

Pathologic nodal status predicts disease-free survival after neoadjuvant chemoradiation for gastroesophageal junction carcinoma.

BACKGROUND: The incidence of carcinoma of the gastroesophageal junction (GEJ) is rapidly increasing, and the prognosis remains poor. We examined outcomes in patients who received neoadjuvant chemoradiation for GEJ tumors to identify factors that predict disease-free (DFS) and overall (OS) survival. METHODS: A retrospective analysis was performed of 101 consecutive patients who received chemoradiation and surgery for GEJ carcinoma between 1992 and 2001. RESULTS: The median DFS and OS of all patients were 16 and 25 months, respectively. Twenty-eight patients with a complete histological response (T0N0) experienced greater DFS compared with all others (P = .02). Node-negative patients, regardless of T stage, experienced improved median DFS (24 months) compared with N1 patients (9 months; P = .01). Preoperative stage, age, tumor location, or Barrett's esophagus did not independently predict OS by univariate analysis. Multivariate analysis demonstrated that only posttreatment nodal status (P = .03)-not the degree of primary tumor response-predicted DFS. CONCLUSIONS: The nodal status of patients with GEJ tumors after neoadjuvant therapy is predictive of DFS after resection. The poor outcome in node-positive patients supports postneoadjuvant therapy nodal staging, because surgical aggressiveness should be tempered by the realization that cure is unlikely and median survival is short.

Adult↗

PubMed2006

Electroacupuncture improves restraint stress-induced delay of gastric emptying via central glutaminergic pathways in conscious rats.

Acupuncture has been used for treating functional gastrointestinal (GI) disorders. Animal studies demonstrated that acupuncture improves various stress-induced physiological responses. We investigated the effects of electroacupuncture (EA) at ST-36 (Zusanli; lower limb) on stress-induced delay of gastric emptying. Solid food gastric emptying in 90 min was significantly delayed by restraint stress (27.3 +/- 2.1%, n = 8), compared to that of controls (64 +/- 2.1%, n = 8). Restraint stress-induced delay of gastric emptying was significantly restored by the intracisternal (IC)-injection of GABA(A) receptor antagonist, bicuculline methiodide (46.5 +/- 3.1%; n = 6) and GABA(B) receptor antagonist, phaclofen (48 +/- 3.3%; n = 6). Delayed gastric emptying induced by restraint stress was significantly improved by EA at ST-36 (49.7 +/- 1.4%). The stimulatory effect of EA on stress-induced delay of gastric emptying was prevented by pretreatment with IC-injection of glutamate receptor antagonist, kynurenic acid (30.1 +/- 2.1%). In conclusion, restraint stress-induced delay of gastric emptying is mediated via central GABA(A) and GABA(B) receptors. EA at ST-36 stimulates glutaminergic neurons in the brainstem resulting in improvement of stress-induced delay of gastric emptying.

Animals↗

PubMed2006

Effect of neoadjuvant chemoradiation on operative mortality and morbidity for pancreaticoduodenectomy.

BACKGROUND: Neoadjuvant chemoradiotherapy (neo-CRT) is being used with increasing frequency for periampullary tumors, but how it alters the complication rate of pancreaticoduodenectomy (PD) is unclear. METHODS: A retrospective analysis was conducted of 79 patients with periampullary malignancies who received 5-fluorouracil-based neo-CRT followed by PD. RESULTS: There was no difference in mortality between PD after neo-CRT (3.8%) and conventional PD for either malignant (4.5%) or benign (2.2%) disease. Focusing only on patients with malignancy, the neo-CRT group had a significantly lower pancreatic leak rate than the conventional group (10% vs. 43%; P < .001). Intra-abdominal abscesses were less common in the neo-CRT group (8.8% vs. 21%; P = .019), and there was one (1.2%) amylase-rich abscess in neo-CRT group, compared with eight (12%) in the conventional group. In addition, two patients in the conventional group died of leak-associated sepsis, compared with none in the neo-CRT group. Multivariate analysis revealed that neoadjuvant chemoradiation (odds ratio, .15) was the most significant factor associated with a reduced risk of pancreatic leak. CONCLUSIONS: Neo-CRT does not increase the mortality or morbidity of PD. In contrast, neo-CRT was associated with a marked reduction in the incidence of pancreatic leak, as well as leak-associated morbidity and mortality.

Adult↗

PubMed2006

A phase I study of eniluracil/5-FU in combination with radiation therapy for potentially resectable and/or unresectable cancer of the pancreas and distal biliary tract.

PURPOSE: Eniluracil is an effective inactivator of dihydropyrimidine dehydrogenase (DPD). It allows for oral dosing of 5-fluorouracil (5-FU), which may potentially improve the antitumor activity of 5-FU when delivered concurrently with radiotherapy while avoiding the inconvenience and morbidity of continuous infusion (CI) 5-FU. We addressed the safety of oral eniluracil/5-FU combined with radiation therapy and determined the profile of dose-limiting toxicities and recommended Phase II dose (RPTD) in patients with pancreatic and hepatobiliary cancers. METHODS AND MATERIALS: Patients with resectable or locally advanced pancreatic and biliary cancer received eniluracil (starting at 6.0 mg/m(2) q12h)/5-FU (starting at 0.6 mg/m(2) q12h). Eniluracil/5-FU were given concurrently with preoperative radiation to 4500 cGy followed by 540 cGy by reduced fields. Surgery was considered 4 weeks after completion of therapy. RESULTS: Thirteen patients were enrolled. Chemoradiotherapy was completed in all patients. The MTD was not reached and, thus, the RPTD of eniluracil/5-FU was determined to be 10 mg/m(2) q12h/1 mg/m(2) q12h. Two patients with locally advanced disease had a 30-45 percent cross-sectional tumor reduction, one of which underwent margin-negative resection. Two of 5 patients with pancreatic cancer, and 1 of 3 patients with cholangiocarcinoma, with underwent exploratory surgery had margin-negative resections. One patient had a pathologic complete response (pCR). Patient 5-FU plasma exposure increased slightly from Day 8 to Day 31. CONCLUSION: Preoperative chemoradiation with oral eniluracil/5-FU is feasible, well tolerated, and potentially effective in the neoadjuvant setting. Further investigation of oral fluoropyrimidines as radiosensitizers for pancreaticobiliary malignancies is warranted.

Aged↗

PubMed2006

Productivity measures associated with a patient access initiative.

OBJECTIVE: To assess financial performance associated with a patient 7-day access initiative. BACKGROUND DATA: Patient access to clinical services is frequently an obstacle at academic medical centers. Conflicting surgeon priorities among academic, clinical, educational, and leadership duties often create difficulties for patient entry into the "system." METHODS: The scope and objectives were identified to be: design of a standard, simple new patient appointment process, design of a standard process in cases where an appointment is not available in 7 days, use subspecialty team search capabilities, minimize/eliminate prescheduling requirements, centralize appointment scheduling, and creation and reporting of 7-day access metrics. Following maturation of the process, the 7-day access metrics from the period July 2004 to December 2004 and January 2005 to June 2005 were compared with corresponding time periods from calendar years 2001, 2002, and 2003. RESULTS: Payor mix was unaltered. The median waiting time for a new patient appointment decreased from 21 days to 10 days. When compared with calendar years 2001, 2002, and 2003, respectively, the 2 periods of the 7-day access initiative in calendar years 2004 and 2005 were associated with significantly increased visits, new patients, operative procedures, hospital charges, and physician charges. CONCLUSIONS: Implementation of a 7-day access initiative can significantly increase financial productivity of general surgery groups in academic medical centers. We conclude that simplifying access to services can benefit academic surgical practices. Sustaining this level of productivity will continue to prove challenging.

Algorithms↗

PubMed2005

Comparative analysis of vagotomy and drainage versus vagotomy and resection procedures for bleeding peptic ulcer disease: results of 907 patients from the Department of Veterans Affairs National Surgical Quality Improvement Program database.

BACKGROUND: The purpose of this study was to determine postoperative outcomes and risk factors for morbidity and mortality in patients requiring surgery for bleeding peptic ulcer disease (PUD). Vagotomy and drainage procedures are technically simpler but are usually associated with higher ulcer recurrence rates. In contrast, vagotomy and resection approaches offer lower ulcer recurrences but represent much more challenging operations and are associated with considerable morbidity and mortality. STUDY DESIGN: Data collected through the Department of Veterans Affairs National Surgical Quality Improvement Program database from 1991 to 2001 were submitted for stepwise logistic regression analysis for prediction of 30-day postoperative morbidity and mortality, rebleeding, and postoperative length of stay. The study population included all patients operated on for bleeding PUD within an 11-year period. RESULTS: The 30-day morbidity, mortality, and rebleeding rates were comparable between surgical groups. Age, American Society of Anesthesiologists class, presence of ascites, coma, diabetes, functional status, hemiplegia, and history of steroid use were predictors of postoperative death. Risk factors for rebleeding included dependent functional status, history of congestive heart failure, smoking, steroid use, and preoperative transfusions. Having a resective procedure, American Society of Anesthesiologists class, hemiplegia, history of COPD, and requiring ventilator-assisted respirations before surgery were positively associated with increased length of hospital stay. CONCLUSIONS: No differences were observed in 30-day mortality, morbidity, or rebleeding rates between surgical groups. Having a resective procedure was a predictor of prolonged postoperative stay. Dependent status and chronic use of steroids were predictors of both rebleeding and postoperative mortality.

Academic Medical Centers↗

PubMed2005

Peripherally administered CRF stimulates colonic motility via central CRF receptors and vagal pathways in conscious rats.

Corticotropin releasing factor (CRF) is one of the most important factors in the mechanism of stress-induced stimulation of colonic motility. However, it is controversial whether stress-induced stimulation of colonic motility is mediated via central or peripheral CRF receptors. We investigated the hypothesis that peripherally injected CRF accelerates colonic motility through the central CRF receptor, but not the peripheral CRF receptor. A strain gauge transducer was sutured on the serosal surface of the proximal colon. Colonic motility was monitored before and after the peripheral injection of CRF. An in vitro muscle strip study was also performed to investigate the peripheral effects of CRF. Subcutaneous injection of CRF (30-100 microg/kg) stimulated colonic motility in a dose-dependent manner. The stimulatory effect of peripherally administered CRF on colonic motility was abolished by truncal vagotomy, hexamethonium, atropine, and intracisternal injection of astressin (a CRF receptor antagonist). No responses to CRF (10(-9) -10(-7) M) of the muscle strips of the proximal colon were observed. These results suggest that the stimulatory effect of colonic motility in response to peripheral administration of CRF is mediated by the vagus nerve, nicotinic receptors, muscarinic receptors, and CRF receptors of the brain stem. It is concluded that peripherally administered CRF reaches the area postrema and activates the dorsal nucleus of vagi via central CRF receptors, resulting in stimulation of the vagal efferent and cholinergic transmission of the proximal colon.

Afferent Pathways↗

PubMed2005

The herbal medicine, Dai-Kenchu-to, accelerates delayed gastrointestinal transit after the operation in rats.

BACKGROUND: Post-operative ileus (POI) is a transient bowel dysmotility after operation. We have previously shown that laparotomy alone significantly delayed gastrointestinal (GI) transit, compared to anesthesia alone. The GI transit was further delayed after laparotomy plus intestinal manipulation. Dai-Kenchu-to (DKT), an herbal medicine, has been used for treating adhesive bowel obstruction in Japan. We studied whether DKT improves delayed GI transit after the operation, with or without morphine administration in rats. MATERIALS AND METHODS: Under isoflurane anesthesia, POI was induced by laparotomy with intestinal manipulation. Immediately after the operation, the rats received 51Cr by gavage. Three hours after the operation, the rats were sacrificed and GI transit was estimated by calculating the geometric center (GC). DKT (120, 360, and 1,200 mg/kg) were administered by gavage after the operation, with or without morphine administration (1 mg/kg s.c.). A muscarinic receptor antagonist (atropine; 50 mug/kg), a 5HT3 receptor antagonist (ondansetron; 1 mg/kg) and a 5HT4 receptor antagonist (GR113,808; 3 mg/kg) were administered before the operation. Truncal vagotomy was performed preceding the operation. RESULTS: Laparotomy with intestinal manipulation produced a significant delay in GI transit (GC = 2.93 +/- 0.16), compared to that of anesthesia alone (9.51 +/- 0.45). DKT at the dose of 360 mg/kg (GC = 3.77 +/- 0.10, P < 0.01) and 1,200 mg/kg (GC = 3.77 +/- 0.20, P < 0.01) significantly accelerated delayed GI transit induced by operation. Ondansetron, GR113,808, atropine, and truncal vagotomy abolished the stimulatory effect of DKT (360 mg/kg). When morphine was administered, GI transit was further reduced (GC = 1.97 +/- 0.10). DKT at the dose of 360 mg/kg (GC = 2.81 +/- 0.22, P < 0.05) and 1,200 mg/kg (GC = 2.87 +/- 0.23, P < 0.05) significantly improved delayed GI transit in morphine treated rats. CONCLUSIONS: DKT accelerates delayed GI transit induced by intestinal manipulation with and without concomitant morphine administration. DKT treatment may be useful for the patients with POI.

Analgesics, Opioid↗

PubMed2005

Electroacupuncture at ST-36 accelerates colonic motility and transit in freely moving conscious rats.

Acupuncture is useful for functional bowel diseases, such as constipation and diarrhea. However, the mechanisms of beneficial effects of acupuncture on colonic function have scarcely ever been investigated. We tested the hypothesis that electroacupuncture (EA) at ST-36 stimulates colonic motility and transit via a parasympathetic pathway in conscious rats. Hook-shaped needles were inserted at bilateral ST-36 (lower limb) or BL-21 (back) and electrically stimulated at 10 Hz for 20 min. We also studied c-Fos expression in response to EA at ST-36 in Barrington's nucleus of the pons. EA at ST-36, but not BL-21, significantly increased the amplitude of motility at the distal colon. The calculated motility index of the distal colon increased to 132 +/- 9.9% of basal levels (n = 14, P < 0.05). In contrast, EA at ST-36 had no stimulatory effects in the proximal colon. EA at ST-36 significantly accelerated colonic transit [geometric center (GC) = 6.76 +/- 0.42, n = 9, P < 0.001] compared with EA at BL-21 (GC = 5.23 +/- 0.39, n = 7). The stimulatory effect of EA at ST-36 on colonic motility and transit was abolished by pretreatment with atropine. EA-induced acceleration of colonic transit was also abolished by extrinsic nerve denervation of the distal colon (GC = 4.69 +/- 0.33, n = 6). The number of c-Fos-immunopositive cells at Barrington's nucleus significantly increased in response to EA at ST-36 to 8.1 +/- 1.1 cells/section compared with that of controls (2.4 +/- 0.5 cells/section, n = 3, P < 0.01). It is concluded that EA at ST-36 stimulates distal colonic motility and accelerates colonic transit via a sacral parasympathetic efferent pathway (pelvic nerve). Barrington's nucleus plays an important role in mediating EA-induced distal colonic motility in conscious rats.

Acupuncture Points↗

PubMed2005

Restraint stress augments postprandial gastric contractions but impairs antropyloric coordination in conscious rats.

Central corticotropin-releasing factor (CRF) plays an important role in mediating restraint stress-induced delayed gastric emptying. However, it is unclear how restraint stress modulates gastric motility to delay gastric emptying. Inasmuch as solid gastric emptying is regulated via antropyloric coordination, we hypothesized that restraint stress impairs antropyloric coordination, resulting in delayed solid gastric emptying in conscious rats. Two strain gauge transducers were sutured onto the serosal surface of the antrum and pylorus, and postprandial gastric motility was monitored before, during, and after restraint stress. Antropyloric coordination, defined as a propagated single contraction from the antrum to the pylorus within 10 s, was followed by > or = 20 s of quiescence. Restraint stress enhanced postprandial gastric motility in the antrum and pylorus to 140 +/- 9% and 134 +/- 9% of basal, respectively (n = 6). The number of episodes of antropyloric coordination before restraint stress, 2.4 +/- 0.4/10 min, was significantly reduced to 0.6 +/- 0.3/10 min by restraint stress. Intracisternal injection of the CRF type 2 receptor antagonist astressin 2B (60 microg) or guanethidine partially restored restraint stress-induced impairment of antropyloric coordination (1.6 +/- 0.3/10 min, n = 6). The restraint stress-induced augmentation of antral and pyloric contractions was increased by astressin 2B and guanethidine but abolished by atropine, hexamethonium, and vagotomy. Restraint stress enhanced postprandial gastric motility via a vagal cholinergic pathway. Restraint stress-induced delay of solid gastric emptying is due to impairment of antropyloric coordination. Restraint stress-induced impairment of antropyloric coordination might be mediated via a central CRF pathway.

Animals↗

PubMed2005

Adjuvant external-beam radiotherapy with concurrent chemotherapy after resection of primary gallbladder carcinoma: a 23-year experience.

PURPOSE: Primary adenocarcinoma of the gallbladder is a rare malignancy. To better define the role of adjuvant radiation therapy and chemotherapy, a retrospective analysis of the outcome of patients undergoing surgery and adjuvant therapy was undertaken. METHODS AND MATERIALS: Twenty-two patients with primary and nonmetastatic gallbladder cancer were treated with radiation therapy after surgical resection. Median radiation dose was 45 Gy. Eighteen patients received concurrent 5-fluorouracil (5-FU) chemotherapy. Median follow-up was 1.7 years in all patients and 3.9 years in survivors. RESULTS: The 5-year actuarial overall survival, disease-free survival, metastases-free survival, and local-regional control of all 22 patients were 37%, 33%, 36%, and 59%, respectively. Median survival for all patients was 1.9 years. CONCLUSION: Our series suggests that an approach of radical resection followed by external-beam radiation therapy with radiosensitizing 5-FU in patients with locally advanced, nonmetastatic carcinoma of the gallbladder may improve survival. This regimen should be considered in patients with resectable gallbladder carcinoma.

Adult↗