Synthesis of a cyclic fibrin-like peptide and its analysis by fast atom bombardment mass spectrometry

For immunochemical purposes, a cyclic 12-peptide was synthesized to model the γ-γ-chain cross-link site in human fibrin. The model was based upon the structure proposed by Chen & Doolittle (Biochemistry (1971) 10, 4486–4491) which is characterized by two reciprocating e -(γ-Glu)Lys bonds between adjacent fibrin γ-chains oriented in an antiparallel manner. To achieve the antiparallel orientation of the peptide backbone, Pro and Gly were inserted at positions 6 and 7 of the linear 12-peptide: acetyl-Gly-Glu-Gln-His-His-Pro-Gly-Gly-Gly-Ala-Lys-Gly-amide. The insertions were made to facilitate a reverse turn of the peptide during the last synthetic step, which was formation of the e -(γ-Glu)Lys bond between Glu at position 2 and Lys at position 11 with diphenylphosphorylazide. The resulting cyclic peptide represented half of the symmetrical cross-linked region in clotted fibrin. Following purification by HPLC, both linear and cyclic 12-peptides were analyzed by fast atom bombardment mass spectrometry. Abundant molecular protonated ions were observed for both peptides. In addition, the amino acid sequence of the linear peptide and the location of the e -(γ-Glu)Lys bond in the cyclized peptide could be verified.     

Superior Mesenteric Artery Syndrome Simulating Acute Pancreatitis

A case of infrapapillary duodenal obstruction secondary to the superior mesenteric artery syndrome is reported. The clinical picture and laboratory data simulated acute pancreatitis but no evidence of pancreatic disease was noted at surgical exploration. A review of the causative factors and treatment of the superior mesenteric artery syndrome is presented along with the differential diagnosis of infrapapillary duodenal obstruction.     

Systemic Mastocytosis and the Mastocytosis Syndrome

A patient with extensive systemic mastocytosis and the mastocytosis syndrome was studied by light and electron microscopy. Mast cell proliferation was found in the bone marrow, the liver, spleen and lymph node. In addition, the patient had telangiectasia macularis eruptiva perstans and elevated histamine levels.     

Left Thoracotomy Reoperation for Coronary Artery Disease

Twenty patients underwent reoperative coronary artery bypass grafting (CABG) through a left thoracotomy since 1971. This was their second CABG in 16 patients, third in three patients and fourth in one patient. Surgery was performed from 1 to 16 years following the initial procedure. Demographic data showed no significant variation from patients undergoing standard reoperative CAGB in this institution. Ejection fraction varied between 30% and 73%. Cardiopulmonary bypass technic has gradually developed since 1971, using the left femoral artery and vein. For venous cannulation a 50-cm long catheter was positioned in the right atrium. Monitoring included pulmonary artery catheter with oximetry. Fibrillatory arrest of the heart was utilized with 18-33 degrees C core cooling cardioplegia. The left internal mammary artery (6) and reverse saphenous veins (44) were used for an average of 2.5 grafts per patient. The proximal anastomosis was placed on the descending thoracic aorta or the left subclavian artery. There were two early and no late deaths. Sixteen patients were restudied before discharge from the hospital with an early graft patency rate of 98% (41/42). The left thoracotomy approach may be preferable in selected cases of redo CABG. The danger of damage to the heart and patent grafts is greatly reduced.     

Use of the Syrian Hamster Embryo Cell Transformation Assay for Determining the Carcinogenic Potential of Heavy Metal Compounds

Cobalt sulfate hydrate, gallium arsenide, molybdenum trioxide,vanadium pentoxide, and nickel sulfate heptahydrate were testedin the Syrian hamster embryo (SHE) assay in order to increasethe SHE assay database for heavy metals. All five compoundsproduced significant morphological transformation at one ormore doses in a dose-responsive manner. Cobalt sulfate hydrate,gallium arsenide, molybdenum trioxide, and nickel (II) sulfateheptahydrate were all positive with a 24-hr exposure, suggestingdirect DNA perturbation. Vanadium pentoxide was negative witha 24-hr exposure, but positive with a 7-day exposure. This patternof response (24-hr SHE negative/7-day SHE positive) has beenseen with other chemicals which have tumor promotion-like characteristics.Since the inception of the use of the SHE cell transformationassay for detecting the neoplastic transformation potentialof chemicals, over 42 heavy metal compounds have been testedin this assay. Based on the 24 metal compounds which have beentested in the SHE, Salmonella, and some type of rodent bioassay,the SHE assay is 92% concordant with rodent bioassay carcinogenicityresults, including a sensitivity of 95% (21/22) and a specificityof 50% (1/2). At this time, the measure of SHE assay specificityfor rodent carcinogenicity of metals is limited by the paucityof metal compounds which are rodent noncarcinogens. The Salmonellaassay results are only 33% concordant with the rodent bioassayfor these same chemicals. This relatively high concordance betweenthe SHE assay and the rodent bioassay carcinogenicity resultsdemonstrates the utility of the SHE assay for determining thecarcinogenic potential of heavy metal compounds in rodent Cancerbioassays.     

Clinical Experience With the Prevention of Rh-lsoimmunization: A Historical Comparative Analysis

ABSTRACT: Clinical experience with prevention of Rh-immunization is reviewed. The pathogenesis of hemolytic disease and the chemistry of prophylaxis is explained. The factors which effect antigenic expression are delineated. The clinical indications for prevention of AMIS are reviewed. International data pertaining to Rhesonativ are presented from postpartum trials and antepartum trials. A protocol for antepartum administration of anti-Rh immunoglobulin is given.     

The atrophogenic effect of crude coal tar on human epidermis

The effects of crude coal tar on human epidermis were studied in fourteen healthy young adult males. A 20%, reduction in viable epidermal thickness, as determined by computer assisted analytical microscopy, was observed after 40 days of topical treatment. Prior to this long term effect of crude coal tar, an initial transient hyperplasia was observed during the first 2 weeks of treatment. These findings indicate that crude coal tar by itself can act as a cytostatic agent on normal human skin, when applied intensively.     

Peritonitis in Patients with Liver Disease and Ascites

Peritonitis in patients with pre-existing liver disease and ascites may be secondary to a local abdominal condition which potentially requires surgery for cure, or alternatively, may be spontaneous in origin. For the latter, antimicrobials are therapeutic while surgery is contraindicated. An easily accessible and important clue for distinguishing these forms of peritonitis may be found in the microbiology of ascitic fluid. Visualization on gram stain smear or recovery on culture of multiple organisms and/or anaerobes favors local abdominal disease over spontaneous peritonitis. The presence of Candida species in the ascitic fluid of such patients, although less common, is highly significant. In the absence of peritoneal dialysis, recent abdominal surgery, or risk factors for disseminated candidiasis, the isolation of Candida suggests specifically gastrointestinal perforation.