Incommmensurability and unconventional superconductor to insulator transition in the hubbard model with bond-charge interaction

We determine the quantum phase diagram of the one-dimensional Hubbard model with bond-charge interaction X in addition to the usual Coulomb repulsion U>0 at half-filling. For large enough X<t the model shows three phases. For large U the system is in the spin-density wave phase as in the usual Hubbard model. As U decreases, there is first a spin transition to a spontaneously dimerized bond-ordered wave phase and then a charge transition to a novel phase in which the dominant correlations at large distances correspond to an incommensurate singlet superconductor.

Combined laparoendoscopic approach for biliary lithiasis treatment

BACKGROUND/AIMS

The treatment of common bile duct stones diagnosed during videolaparoscopic cholecystectomy is still under debate. In cases of suspected common bile duct stones, a double approach with endoscopic retrograde cholangiopancreatography either prior to, or following videolaparoscopic cholecystectomy is the current routine in many centers. An intraoperative endoscopic retrograde cholangiopancreatography with endoscopic papillosphincterotomy and stone extraction has recently been proposed.

METHODOLOGY

We compared the approaches for suspected common bile duct stones in 21 cases of combined intervention endoscopic retrograde cholangiopancreatography during videolaparoscopic cholecystectomy to 17 cases of sequential intervention (endoscopic retrograde cholangiopancreatography prior to videolaparoscopic cholecystectomy). Complications and postoperative monitoring are discussed and reported on the basis of hospital stay.

RESULTS

Although the efficacy and the complications are similar, patients treated with the sequential approach stayed in the hospital longer because of the double monitoring period during both after endoscopic retrograde cholangiopancreatography and after videolaparoscopic cholecystectomy.

CONCLUSIONS

A combined approach to suspected common bile duct stones during videolaparoscopic cholecystectomy could be an effective and a financially worthwhile treatment.

[Massive hemorrhage from duodenal adenocarcinoma. A case report]

The Authors report a case of acute onset anaemia due to a bleeding duodenal adenocarcinoma, stressing the rarity of this clinical situation. Only in few cases such an important bleeding has been pointed out to require an emergency surgical treatment. The diagnostic and therapeutical criteria are exposed and compared with the literature ones. The Authors indicate duodenopancreatectomy as the only resective surgical procedure that can offer recovery or a chance of a long disease-free survival.

[Extended and palliative surgery in the treatment of gastric cancer in advanced stage]

Five hundred and fifty patients operated between 1965 and 1983 for stomach carcinoma were included in the study. Of these, 244 (44.4%) underwent extended (54 patients) or palliative surgery (190 patients) due to the extragastric diffusion of the neoplasia. Global postoperative mortality for patients undergoing extended surgery was 16.7% and the five-year survival rate was 18.5%; in the case of those undergoing palliative surgery the postoperative mortality rate was 30.5% and the two-year survival rate was 14% for resection and 4% for derivatives. Patients who underwent a derivative operation showed an easing of symptoms and an improved quality of life. On the basis of these results the Authors consider that the possibility of extended surgery should still be carefully evaluated in patients in whom a stomach tumour has exceeded the gastric boundary, irrespective of its extent, since the limit of radical surgery is not related to the extension of surgical demolition but to the entity of the extragastric diffusion of the neoplasia. In addition, surgical abstention is not always justified even in patients in whom surgery cannot be curative since a 10% five-year survival rate was observed in patients undergoing palliative resection.

[Neurotoxicity of intra-arterial cis-platinum (CDDP) in the locoregional treatment of diffuse liver metastasis of carcinoma of the colon and rectum]

Peripheral neurotoxicity of i.v. cisplatin (CDDP) at high cumulative dosage is well documented. On the contrary neurotoxicity of CDDP following intra-arterial administration is less known. Five patients with liver metastasis from colorectal carcinoma have been treated with intraarterial CDDP and i.v. 5-fluorouracil according to a trial of the National Registry on Implantable Devices (RNSI); in these patients a severe peripheral neurotoxicity has been observed since the fourth cycle of chemotherapy. In the present paper we report the electroneurographic changes observed immediately after chemotherapy and several months later. Clinical characteristics of neuropathy following i.a. CDDP are the following: preferentially localized at the distal extremities of the limbs, exclusively sensitive, not reversible.

[Distal gastrectomy with Y gastroenteroanastomosis not associated with vagotomy in elective surgical treatment of gastroduodenal ulcer. Clinical and functional long-term results]

During the period 1977-1984, 53 patients with peptic ulcer resistant to H2-blockers (29 gastric and 24 duodenal ulcers) were submitted to distal gastrectomy with Roux-en-Y gastroenteroanastomosis not associated with vagotomy. The indication was used as an alternative to proximal vagotomy in cases with delayed gastric emptying, high acid output, perforation or bleeding. The study plan consisted of serial clinical and instrumental controls including determination of basal (BAO) or maximal (MAO) acid output. Operative mortality was nil. At various times after the operation, 4 patients died for unrelated reasons and 3 were lost to follow-up. Median follow-up was 84 months with an interval of from 4 to 137 months. Fifty-one patients were followed up for at least one year and 49 for at least two. Five patients (2 gastric and 3 duodenal ulcers) developed peptic recurrences (Visick IV, 9.8%) by the end of the first postoperative year and, in all cases but one, healed stably by the second year after medical (3 cases) or surgical (1 case) therapy. In the remaining patients, Visick was grade III in 6 cases (4 gastric and 2 duodenal ulcers), grade II in 6 and grade I in 34. Before operation, mean values (+/- SD) of BAO and MAO were respectively 5.84 +/- 5.03 and 29.6 +/- 18.6 mEq/h. In the immediate postoperative period there was a considerable reduction in BAO (p less than 0.02) and MAO (p less than 0.03) which continued up to the third postoperative year with a tendency to further progressive reduction in MAO. In spite of a considerable individual variability in dimensions and temporal evolution, the phenomenon occurred qualitatively in all cases. No significant difference was observed in the behaviour of BAO and MAO in gastric ulcers by comparison with duodenal ulcers and in cases with recurrence and Visick III compared to those with a favourable clinical result.

[Pseudoaneurysm of the right iliac artery with fistula into the cecum. A clinical case]

A case is reported of pseudoaneurysm of the right iliac artery secondary to an endarterectomy with dacron patch due to atherosclerosis performed 4 years ago. The case presented acute anemia and massive enteric hemorrhage subsequent to arterial rupture into the cecum. Because of the dramatic onset, the patient was immediately operated. The surgical procedure used was total pseudoaneurysm excision, "in situ" by-pass with dacron prosthesis and suture of the cecum. The problems of pathophysiology, diagnosis, symptoms and management are discussed and compared to previously published cases. The peculiarity of the described case is underlined.

Delayed development and rupture of an aortic aneurysm after closed abdominal trauma

A case is reported of a patient who, following the surgical repair of a lesion of the superior mesenteric artery secondary to a closed abdominal trauma, slowly developed an aneurysm of the abdominal aorta which subsequently ruptured. Surgical management of the aneurysm by aortic graft implantation proved successful.

[Degree of parietal penetration of gastric cancer in relation to medium- and long-term survival]

The Authors analysed their experience about gastric carcinoma, with particular reference to short, middle and long time survival in relation to the degree of parietal penetration. In the patients without remote metastases, the survival till 5 years depends mainly on this factor, whereas the lymphonodal spreading plays a secundary rôle, especially in the cases where the tumour deeply infiltrated the gastric wall. Lymphoadenectomy, therefore, seems essential in cases of neoplasm with low degree of parietal penetration, whereas in those with high degree it does not seem determinant on the remote results.

[Validity of distal subtotal gastroresection in the treatment of tumors of the lower 1/3 of the stomach]

The Authors analysed the results of a casuistry of 75 patients subjected to radical subtotal gastroresection for carcinoma of the distal third of stomach, with the purpose to verify the validity of such operation, as compared to the total gastrectomy on principle. The postoperative mortality reached 8% and morbidity 8.7%. The survival after 5 years reached 42%. 85% of the patients, at checkings, resulted in good or excellent conditions (Visik 1-2). On the basis of these data, the Authors conclude the distal subtotal gastric resection should be considered the choice treatment for tumours of the lower third of stomach.

[Evaluation of the functional modifications of the lower esophageal sphincter after use of the Angelchik prosthesis]

The manometric recording of Lower Esophageal Sphincter (LES) has been made in 8 patients who have undergone surgical apposition of Angelchik prosthesis for hiatal hernia. The patients underwent an esophageal manometric study in the preoperative period, one month and one year after the intervention. In the preoperative patients, the mean LES pressure was 10,3 +/- 0,5 mmHg and there was sphincterial incoordination to peristaltic waves after swallow. In one month postoperative patients the LESP was 20,1 +/- 1,0 mmHg (p less than 0,001), and one year after the LESP was 17,0 +/- 0,3 (p less than 0,001) with an ameliorated coordination of the LES activity in response to swallow. Therefore, during postoperative manometric controls the Authors identified a high pressure subdiaphragmatic zone unmodified by deglutitory acts which was not present in the preoperative investigation. Probably the presence of this zone would been explained as a consequence of mechanical action of the prosthesis and the postsurgical fibrino-reaction around the prosthesis. The Authors discussed the results obtained and their importance to Angelchik prosthesis employment for surgical correction of hiatal hernia.

Rational indications for sphincterotomy through intraoperative cholangiomanometry

The loss of function of Oddi's sphincter due to sclerosis secondary to a lithiasic or alithiasic phlogosis, is the only rational indication for sphincterotomy. An operative test of the Oddi sphincter function is proposed, based on an original manometric procedure. This method, employed on 567 patients undergoing biliary surgery, allowed demonstration of a loss of function of Oddi's sphincter in 53 patients (9.4%), in whom a sphincterotomy was performed.

Effect of pirenzepine on L--amino acids stimulated gastric acid secretion and serum gastrin levels in peptic ulcer disease in men

This report tests in men the effect of Pirenzepine on L-Amino acids stimulated gastric secretion and serum gastrin levels in order to evaluate the true antimuscarinic selective properties of this drug. Since L-Amino acids given intravenously stimulate gastric acid secretion by a mechanism of action selective on the cholinergic receptors of the gastric parietal cells, not mediated through the vagus nerve, gastrin or other gut hormones. Pirenzepine should be an L-Amino acids antagonist as far as the gastric acid secretion is concerned. By confirming this presumed antagonism between Pirenzepine and L-Amino acids given intravenously, this report points out in men the selective antimuscarinic effect of this anti ulcer drug on the high affinity muscarinic receptors of the gastric parietal cells. Finally a decrease in gastrin serum levels was observed after the i.v. administration of Pirenzepine and this could be explained by a possible effect of blockade of this drug on the cholinergic receptors of the antral G cells, but these data need further experimental confirm. Attention is then paid to the different mechanism of action between Pirenzepine, H2 receptors antagonist drugs and other anti ulcer drugs on healing gastric or duodenal peptic ulcers.

[Postoperative functional evaluation and pharmacological study of Oddi's sphincter by means of cholangiomanometry using a Kehr tube]

The Authors report their experience of postoperative cholangiomanometry carried out through a T-tube on 19 patients; in 13 of such patients the Oddi's sphincter was intact, while 6 of them underwent sphincterectomy. In 8 patient's a manometric study of the duodenum was associated. They performed both variable flow and pressure and constant flow manometry and their results show that such examination is a reliable test both for the functional evaluation of the surgical procedure, and for the study of the action of various drugs on Oddi's sphincter function and its correlation with duodenal motility.

[Short and median term results of 234 cases of gastrectomy with the Billroth II method. Critical evaluation]

234 partial gastrectomies, according to Billroth II technique, were performed for peptic ulcer disease in selective patients from 1969 to 1977. A postoperative study has been carried out to check the efficiency of such operation in the treatment of peptic ulcer disease. Postoperative treatment of peptic ulcer disease. Postoperative mortality was 3.8%, while immediate surgical complications were 6.4%. 145 of this patients could be followed with a special regard for sex, age, way of living, general conditions, ulcer's location and the persisting symptoms at the time of the study. 124 patients (84%) showed good general conditions while 6 (4.1%) needed a second operation for recurrent peptic ulceration or alkaline reflux gastritis. Although this procedure has showed fairly good clinical results the Authors point out the high rate of postoperative mortality for a basically benign disease and the presence of some unpleasant digestive sequelae. Attention is payed to some factors that may play an important role on the pathophysiology of these sequelae.