Bioconjugation of ribonuclease A: a detailed chromatographic and mass spectrometric analysis of chemical modification by a cross-linking reagent.

The modification of ribonuclease A with the heterobifunctional cross-linker, 4-succinimdyloxycarbonyl-methyl-alpha-[2-pyridyldithio]-toluene (SMPT) is described. RNase A has 11 potential sites of modification by the SMPT reagent. Tracking the two-dimensional separation and proteolytic digestion of SMPT-modified RNase A with ESI/FTICR-MS and HPLC/ESI/QIT-MS demonstrates the detailed information about number of SMPT modifications and sites of modification that can be obtained by application of these techniques. Analysis of native and modified RNase A tryptic digests by ESI/FTICR-MS resulted in the identification of the sites of modification. Semiquantitative results of the reactivity of certain lysine residues toward the coupling reagent SMPT are presented. Two sites (lysines 1 and 37) are highly reactive, while three sites (lysines 41, 61, and 104) appear to be unreactive toward SMPT under the conditions used. Experimental results demonstrate that quantitative comparison of relative intensities of peptide sequences of different charge states is not possible. No correlation was found between number of basic residues and sensitivity to detection. Digestion of the modified and unmodified RNase A by subtilisin followed by examination by HPLC/ESI/QIT-MS and MS(n) enabled further investigation of modification on lysines 1 and 7, including modification at the epsilon- and alpha-amino positions on lysine 1.

Reoperations for bleeding portal hypertension. Surgical rescue of surgical failures.

BACKGROUND: Surgery for portal hypertension has a low rebleeding rate. Patients that rebleed can be grossly divided into those who die as a consequence of the episode, those who don't die but develop liver failure (remaining as Child-Pugh C) and those who, in spite of the bleeding episode, retain good liver function (Child-Pugh A or B). At our hospital, the latter group is considered for further surgical treatment. We report here the results of surgical rescue of surgical failures. METHODS: In a twenty year period, 36 patients (30 Child-Pugh A, 6 Child-Pugh B) were reoperated. The files of these patients were reviewed. RESULTS: Average age was 33 years. Cirrhosis was present in 31 cases. All patients were electively reoperated with portal blood flow preserving procedures. Operative mortality for the whole group was 12% and for the Child-Pugh A group 6.6%. Rebleeding was observed in 5.5%. Postoperative incapacitating encephalopathy was recorded in one case (2.7%). Good quality of life was recorded in 84% of the cases. Survival (Kaplan-Meier) was 78% at 6 months and 69% at 5 years. CONCLUSIONS: Surgical failures in low risk patients (Child-Pugh A or B) can be treated by means of surgery, and a low mortality, re-bleeding and encephalopathy rate can be expected. The performance of a portal blood flow preserving procedure is recommended.

Fulminant amebic colitis: analysis of 55 cases.

UNLABELLED: Fulminant amebic colitis is a rare disease with high morbidity and mortality. PURPOSE: This study was designed to identify the most frequent clinical and histopathologic features of fulminant amebic colitis and to analyze results of surgical treatment and the existence of risk factors for mortality. MATERIALS AND METHODS: A retrospective analysis was conducted of clinical and histopathologic data of 55 patients with fulminant amebic colitis. Data were obtained from the files of autopsies and surgical operations that had been performed at a referral center in Mexico from 1943 through 1994. RESULTS: Median age was 52 (range, 18-79) years. There were 34 men (62 percent) and 21 women (38 percent). Diabetes mellitus and chronic alcoholism were the most frequent diseases in association with fulminant amebic colitis (40 and 31 percent, respectively). The most frequent clinical manifestations were abdominal pain, diarrhea, rectal bleeding, and fever. There was a coexistent amebic liver abscess in 54 percent of patients. The main histopathologic characteristics were necrosis, presence of trophozoites, and acute and/or chronic inflammation. Of 25 patients who underwent surgery, only six survived (operative mortality, 76 percent; overall mortality, 89 percent). The variables that correlated with mortality were longer duration of symptoms, lower count of leukocytes, nonsurgical treatment, nonresective surgical procedure, hospital admission before 1971, and invasion of trophozoites into or through the muscularis. CONCLUSIONS: The results may help to obtain an earlier diagnosis and establish proper treatment of fulminant amebic colitis.

[A comparative study of complications after vagotomy-pyloroplasty using Sugiura-Futagawa procedure and surgery of acid peptic disease]. / Estudio comparativo de las complicaciones secundarias a vagotomía-piloroplastia en la operación de Sugiura-Futagawa y en cirugía para enfermedad ácido-péptica.

BACKGROUND: The frequency of complications of vagotomy and pyloroplasty for treating peptic disease is considerable. The modification of the Sugiura-Futagawa procedure includes bilateral truncal vagotomy and pyloroplasty as part of the devascularization, with a low frequency of related complications. AIM: To study the effects after VP in the outcome of both groups of patients. RESULTS: The results of a retrospective, comparative, not randomized, controlled trial of 153 medical records of patients who underwent our modification of the Sugiura-Futagawa operation (SFO) due to Hemorrhagic Portal Hypertension (HPH), and 100 patients with bilateral truncal vagotomy and pyloroplasty (VP) due to Acid-Peptic Disease (APD) are presented. In both groups VP was done. The first group as part of SFO, and the second to treat their disease. We found 47 complications; 40 (40%) were observed in patients who underwent VP for APD and 7 (4%) in SFO: Post-vagotomy Diarrhea (PVD): 11% after APD and 2% after SFO. Dumping Syndrome (DS): 22% and 1%, and Alkaline Reflux Gastritis (ARG): 7% and 0.5% respectively. The calculated risk of developing complications related to vagotomy and pyloroplasty in peptic ulcer disease was 14 times higher. CONCLUSIONS: The incidence of these post VP complications at the SFO group was low (4%), in relation to 40% for the APD; the outcomes were statistically significative (p < 0.05).

Distal splenorenal shunt versus 10-mm low-diameter mesocaval shunt for variceal hemorrhage.

BACKGROUND: Portal hypertension surgery remains a good therapeutic choice for well selected patients with variceal bleeding. The distal splenorenal shunt (DSRS) has shown good long-term results and low-diameter shunts have emerged as an alternate choice. METHODS: A prospective, controlled and not randomized study was designed to compare the DSRS (23 patients) and the low-diameter 10 mm ring reinforced PTFE mesocaval shunt (LDMCS) (22 patients) in low-risk electively operated patients (Child-Pugh A-B). The operation was selected according to the anatomical status of the veins. RESULTS: Both groups were comparable. No differences were observed regarding rebleeding, operative mortality and survival. Significative differences were observed regarding encephalopathy and shunt thrombosis (higher in the LDMCS). Postoperative angiography showed better maintenance of portal blood flow in the DSRS group. CONCLUSIONS: Both operations are adequate alternatives for the elective treatment of portal hypertension in low-risk patients. However, the DSRS has more advantages than the LDMCS.

[Pancreatoduodenectomy in the treatment of carcinoma of Vater's ampulla]. / Pancreatoduodenectomía en el tratamiento de carcinoma del ámpula de Vater.

OBJECTIVE: To analyze clinical characteristics, diagnostic methods, intraoperative findings, morbidity & mortality and outcome of a series of patients with ampullary adenocarcinoma. DESIGN: Retrospective analysis. SETTING: Tertiary-care medical center. PATIENTS: Thirty four consecutive patients who underwent radical resection between 1960 and 1992. RESULTS: The most frequent findings were jaundice (91%), weight loss (44%) and palpable gallbladder (42%). Thirty-three patients (97%) underwent Whipple resection and one total pancreatectomy (3%). The postoperative mortality was 15%. Overall survival at 1, 5, 10 and 14 years was 67, 36, 25 and 17% respectively. Fourteen patients died of tumor recurrence developed more than five years after the resection. CONCLUSION: Radical resection for ampullary carcinoma remains the procedure of first choice in these patients.

[7 cases of carcinoma of the distal choledochus]. / Siete casos de carcinoma del colédoco distal.

Seven patients with carcinoma of the lower third of the extrahepatic bile duct over a twenty year period, were analyzed with emphasis to the presentation, laboratory, surgical findings, histology and outcome. There were four males and three females. The mean age was 59 years (range 53 to 68). All patients presented jaundice, abdominal pain and weight loss. Serum bilirubin levels were over 5 mg/dL in six patients (86%). The most useful diagnostic studies were endoscopic cholangiography, percutaneous cholangiography and computed tomography. All patients underwent a Whipple procedure. There was no operative mortality. In the long term follow-up, three patients were free of disease, and four had died. Tumor recurrence was high (43%) in spite of the curative resection.

[Complications of splenectomy in the Sugiura-Futagawa procedure]. / Complicaciones de la esplenectomía en la operación de Sugiura-Futagawa.

UNLABELLED: Evaluation of the complications of splenectomy in the Sugiura-Futawaga operation. BACKGROUND: Splenectomy in portal hypertension is a more difficult procedure and probably has a higher morbidity and mortality. METHOD: A retrospective study of 155 patients with hemorrhagic portal hypertension treated by means of the Sugiura-Futawaga operation was conducted to evaluate the complications related to splenectomy. RESULTS: Mean age of the patients was 42 years: 81 patients were male and 74 female. In 87 cases liver cirrhosis was shown, 39 cases with portal fibrosis, 23 cases with primary biliary cirrhosis and 6 cases with normal liver (idiopathic portal hypertension). No patient received preoperative immunization against pneumococcus, but received antibiotic prophylaxis. Complications were found in 16 cases (10.3%): 13 of them related to the surgical procedure (peritonitis 3.9%, subphrenic collection 1.9%, pancreatic pseudocyst 1.9% and pancreatic fistula 0.6%) and three related to the absence of spleen (1.9%) with septic shock as manifestation. CONCLUSIONS: The complications related to splenectomy in the Sugiura-Futagawa procedure are low, as well as the overwhelming post-splenectomy infection rate. Splenectomy in the Sugiura-Futagawa operation has no important role in the post-operative morbidity.

[Duodenal cancer]. / Cáncer de duodeno.

UNLABELLED: To analyze the general characteristics and outcome of a cohort of 6 patients with malignant duodenal tumors who underwent surgical radical resection. DESIGN: Longitudinal retrolective study. SETTING: A third level medical center. RESULTS: Mean age was 48 years. M/F ratio was 2:1. The most frequent symptom was duodenal obstruction. Mean time between the beginning of the symptoms and the correct diagnosis was 15 months. Five of six patients demonstrated abnormalities on gastrointestinal X rays. All patients underwent Whipple resection, this was curative in 2, palliative in 2 more and not evaluated in two cases due to operative mortality. Five tumors were adenocarcinomas and one a carcinoid tumor. The long-term mortality occurred in 2 patients. CONCLUSIONS: The diagnosis of primary duodenal carcinoma needs a deep clinical suspicion, some patients when treated by radical resection may experience long-term survival.