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Chemical Ablation (chemical + ablation)
Selected AbstractsDorothy Hodgkin Lecture 2008 Gastric inhibitory polypeptide (GIP) revisited: a new therapeutic target for obesity,diabetes?DIABETIC MEDICINE, Issue 7 2008P. R. Flatt Abstract There is increasing realization that gastric inhibitory polypeptide (GIP) has actions outside of the pancreas and gastrointestinal tract. Most significant is the presence of functional GIP receptors on adipocytes and the appreciation that GIP, secreted strongly in response to fat ingestion, plays a role in the translation of excessive amounts of dietary fat into adipocyte tissue stores. Such effects open up the possibility of exploiting GIP receptor antagonism for the treatment of obesity and insulin resistance. This is borne out by studies in high-fat-fed mice or ob/ob mice with either genetic knockout of GIP receptor or chemical ablation of GIP action using the GIP receptor antagonist, (Pro3)GIP. By causing preferential oxidation of fat, blockade of GIP signalling clears triglyceride deposits from liver and muscle, thereby respectively restoring mechanisms for suppression of hepatic glucose output and cellular glucose uptake. Further studies are needed to determine the applicability of this research to human obesity,diabetes. However, proof of concept is provided by emerging evidence that rapid cure of diabetes in grossly obese subjects undergoing Roux-en-Y bypass surgery is mediated in part by surgical bypass of GIP-secreting K-cells in the upper small intestine. [source] The use of self-expandable metallic stents for palliative treatment of inoperable esophageal cancerDISEASES OF THE ESOPHAGUS, Issue 1 2010A. Eroglu SUMMARY Most patients with esophageal carcinoma present in the advanced stage die from tumor invasion and widespread metastases. Because radical regimens are not appropriate for the majority of patients, and their expected survivals are as short as to be measured by months, the main aim of therapy is palliation with minimum morbidity and mortality. Among the palliative modalities are surgery, external radiotherapy or brachytherapy, dilatation, laser, photodynamic therapy, bipolar electrocoagulation tumor probe, and chemical ablation. The placement of self-expandable metallic stents is another method that improves dysphagia for these patients. In this study, the aim was to evaluate retrospectively the effectiveness of metallic stents deployed because of inoperable malignant esophageal stenosis and esophagotracheal fistulas. The results of 170 patients with 202 stents administered because of inoperable malignant esophageal stenosis and esophagorespiratory fistula between January 2000 and October 2008 at the Ataturk University, Department of Thoracic Surgery, were investigated. Despite epidemiological and clinical data, information regarding relief of dysphagia and quality of life were also examined. One hundred seventy patients with stents were between 28 and 91 years old (mean age 63.7 years ± 11.4 years). Ninety-seven were male and 73 were female. Stent indications were advanced tumors with distant metastasis (82 cases, 48.2%), unresectable tumors (51 cases, 30%), patients who cannot tolerate surgery or chemoradiotherapy (18 cases, 10.5%), local recurrence after primary therapy (1 case, 0.5%), esophagorespiratory fistulas from tumor or therapy (14 cases, 8.2%), and refusal of surgery (4 cases, 2.3%). Dysphagia scores evaluated by a modified Takita's grading system improved from 3.4 before the procedure to 2.6 afterward. The overall complication rate without chest pain was 31.7% (occurring in 64 cases). Mean survival was 177.7 days ± 59.3 days (2,993 days). Quality-of-life scores (The European Organization of Research and Treatment of Cancer QLQ C30) improved from 73 ± 10.3 (57,85) to 112 ± 12.6 (90,125). In therapy of malignant esophageal obstructions, metallic stents provide a significant improvement in dysphagia and require less frequent re-intervention according to other methods of dysphagia palliation such as dilatation, laser, and photodynamic therapy, nearly completely relieve esophagotracheal fistulas and improve quality of life to an important degree. [source] Mapping of Epicardial Activation in a Rabbit Model of Chronic Myocardial Infarction:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2007Endocardial, Epicardial Pacing, Response to Atrial Introduction: This study examines the consequences of a large transmural apical infarct on the epicardial electrical activity in isolated rabbit hearts. Methods and Results: Hearts were isolated 8 weeks after coronary artery ligation. Membrane voltage from the epicardial surface of the left ventricle (LV) including the infarct was monitored using the voltage sensitive dye RH237. Optical action potentials were detected from the epicardial surface of the infarct; the signal amplitude was ,20% of those in the noninfarcted zone (NZ). Epicardial activation mapping of the LV free wall showed that during right atrial (RA) pacing, the activation sequence was not significantly different between infarcted and sham-operated groups. However, direct stimulation of the epicardium in the NZ revealed an area of slow conduction velocity (CV ,5 cm/s,1, ,10% of normal values) at the margin of the infarct zone (IZ). Within the IZ, CV was ,50% of normal. A prominent endocardial rim of myocardium in the infarct was not the source of epicardial optical signals because chemical ablation of the endocardium did not affect the epicardial activation pattern. Concluson: Therefore, remnant groups of myocytes in the mid-wall and epicardium of the infarct scar support normal electrical activation during RA pacing. Areas of delayed conduction emerge only on epicardial stimulation. [source] Light intensity, prey detection and foraging mechanisms of age 0 year yellow perchJOURNAL OF FISH BIOLOGY, Issue 1 2004H. E. Richmond The ability of age-0 year yellow perch Perca flavescans to detect prey using visual and mechano-sensory input was examined during laboratory feeding trials at varying light intensities. Perch were highly effective predators and captured Daphnia pulicaria with 94% overall foraging success at light levels ranging from 0 to 3400 lx. Maximum average reaction distances (5·0 ± 0·8 cm, mean ± s.e.) occurred in front of the fish at 3000 lx and significantly decreased as light intensities fell to <2 lx, with minimum reaction distances (2·8 ± 0·1 cm) observed in the dark. Following chemical ablation of the lateral line, yellow perch showed a significant reduction in reaction distance when compared to the untreated fish at 3000 lx, suggesting that the lateral line may augment visual prey detection at high light levels. A model was created to predict reaction distances for fish feeding with multiple sensory systems that can be applied to a variety of photic environments. This study provides a better understanding of the contribution of vision and the lateral line to prey detection, and relates the reaction distance of age-0 year yellow perch to light intensities similar to those experienced in nature. [source] Monochloramine impairs mucosal blood flow response and healing of gastric lesions in rats: Relation to capsaicin-sensitive sensory neuronsJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 3 2001Koji Takeuchi Abstract Aims: We examined the effects of monochloramine (NH2Cl) on the gastric mucosal blood flow (GMBF) response and the healing of ethanol-induced gastric lesions in rats. Methods: Rats fasted for 18 h were given the 99% ethanol p.o. for induction of gastric lesions, and were fed normally from 1 h later onwards. Monochloramine, at non-ulcerogenic doses (5~20 mmol/L), was given p.o. twice daily for 7 days, starting 2 h after ethanol treatment. Results: Gastric lesions caused by ethanol healed almost completely within 7 days with re-epithelialization. The repeated administration of NH2Cl significantly delayed the healing of ethanol-induced gastric lesions in a dose-dependent manner. The damaged mucosa showed a marked rise in H+ permeability, resulting in luminal acid loss, but this process was accompanied by an increase of mucosal blood flow. Monochloramine did not affect the increased mucosal H+ permeability observed in the stomach after damage by ethanol, but significantly inhibited the mucosal hyperemic response associated with luminal acid loss. Prior exposure of the mucosa to NH2Cl (20 mmol/L) did not affect the gastric hyperemic response caused by mucosal application of misoprostol (a prostaglandin E1 derivative) or NOR-3 (a nitric oxide donor), but totally attenuated the increase of GMBF in response to intragastric capsaicin. Impaired healing and GMBF responses were also observed in rats following chemical ablation of capsaicin-sensitive sensory neurons. Conclusions: These results suggest that NH2Cl impaired the healing of acute gastric mucosal lesions at low concentrations, and this action may be attributable, at least partly, to the impairment of gastric hyperemic response caused by the dysfunction of capsaicin-sensitive sensory neurons. [source] Primary hyperparathyroidism in 29 dogs: diagnosis, treatment, outcome and associated renal failureJOURNAL OF SMALL ANIMAL PRACTICE, Issue 1 2005R. N. A. Gear Objectives: To review the records of 29 dogs diagnosed with primary hyperparathyroidism and see if any factors correlate with renal failure. Methods: Dogs were selected retrospectively from case files from the QVSH and the QMH. Results: The majority of dogs were middle-aged and four were keeshonds. The primary presenting complaints were polyuria and polydipsia. All dogs had an elevated total and ionised plasma calcium concentration. Plasma phosphate concentrations were variable. Ultrasonography of the parathyroid gland revealed nodular enlargement which was found to correlate well with surgical findings. The majority of dogs underwent surgical parathyroidectomy. Five cases were treated by ultrasound-guided chemical ablation of the parathyroid gland, of which only two cases showed a partial response. Three dogs were euthanased within a week of presentation. Seven other dogs had renal failure diagnosed either at presentation or up to six months after parathyroidectomy. The development of renal failure was correlated with total calcium concentration but did not correlate with any other factor, including the calcium phosphate product. Thirteen treated dogs were known to be alive at the time of writing, which was six months to 3.5 years after parathyroidectomy. Clinical Significance: Primary hyperparathyroidism cases with high total calcium were more likely to develop renal failure in this group of dogs; however, the calcium phosphate product did not seem to be a useful predictor. Ultrasound-guided chemical ablation seemed to have limited advantage over surgery. [source] | ||||||||||