Sulfonation of arginine residues as side reaction in Fmoc-peptide synthesis

Several arginine-rich peptides containing the C-terminus of neuropeptide Y (NPY) were prepared by solid phase peptide synthesis using Fmoc chemistry and cleaved from the resin with trifluoroacetic acid (TFA). The products were characterized by fast atom bombardment-MS, LC-thermospray-MS, ion spray-MS/MS, and Edman degradation. The side products could be identified as peptides with sulfonated arginine residues resulting from an unexpected cleavage of Mtr or Pmc protecting groups. The degree of sulfonation depended on the choice and composition of the cleavage solution. Several scavenger mixtures were used and a mixture of thioanisole/thiocresol was found to be the most efficient for suppressing sulfonation. Furthermore treatment with the enzyme arylsulfate-sulfohydrolase desulfonated the peptides yielding the correct sequence.     

Primary effusion lymphoma: a distinct clinicopathologic entity associated with the Kaposi's sarcoma-associated herpes virus

We recently discovered the Kaposi's sarcoma-associated herpes virus (KSHV/HHV-8) in an uncommon and unusual subset of AIDS-related lymphomas that grow mainly in the body cavities as lymphomatous effusions without an identifiable contiguous tumor mass. The consistent presence of KSHV and certain other distinctive features of these body cavity-based lymphomas suggest that they represent a distinct entity. We tested this hypothesis by investigating 19 malignant lymphomatous effusions occurring in the absence of a contiguous tumor mass for their clinical, morphologic, immunophenotypic, viral, and molecular characteristics, KSHV was present in 15 of 19 lymphomas. All four KSHV- negative lymphomatous effusions exhibited Burkitt or Burkitt-like morphology and c-myc gene rearrangements and, therefore, appeared to be Burkitt-type lymphomas occurring in the body cavities. In contrast, all 15 KSHV-positive lymphomatous effusions exhibited a distinctive morphology bridging large-cell immunoblastic lymphoma and anaplastic large-cell lymphoma, and all 12 cases studied lacked c-myc gene rearrangements. In addition, these lymphomas occurred in men (15/15), frequently but not exclusively in association with HIV infection (13/15), in which homosexuality was a risk factor (13/13), presented initially as a lymphomatous effusion (14/15), remained localized to the body cavity of origin (13/15), expressed CD45 (15/15) and one or more activation-associated antigens (9/10) in the frequent absence of B-cell- associated antigens (11/15), exhibited clonal immunoglobulin gene rearrangements (13/13), contained Epstein-Barr virus (14/15), and lacked bcl-2, bcl-6, ras and p53 gene alterations (13/15). These findings strongly suggest that the KSHV-positive malignant lymphomatous effusions represent a distinct clinicopathologic and biologic entity and should be distinguished from other malignant lymphomas occurring in the body cavities. Therefore, we recommend that these malignant lymphomas be designated primary effusion lymphomas (PEL), rather than body cavity-based lymphomas, since this term describes them more accurately and avoids their confusion with other malignant lymphomas that occur in the body cavities. We further recommend that these PEL be considered for inclusion as a new entity in the Revised European- American Lymphoma Classification.     

Gastro-oesophageal reflux in infants under 6 months with cystic fibrosis

AIM: To establish the incidence of pathological gastro-oesophageal reflux (GOR) in newly diagnosed infants with cystic fibrosis and to identify clinical predictors of increased reflux. METHODS: 26 infants with cystic fibrosis less than 6 months of age (14 male, 12 female; mean (SEM) age 2.1 (0.21) months, range 0.8 to 5.6 months) underwent prolonged oesophageal pH monitoring (mean duration 27.1 (0.49) hours; range 21.3 to 30.2 hours). Reflux symptoms, anthropometric variables, pancreatic status, meconium ileus, genotype, and chest x ray findings were correlated with pH monitoring data. RESULTS: Five infants (19.2%) had an abnormal fractional reflux time of greater than 10%, seven (26.9%) of 5-10%, and 14 (53.8%) of below 5%. Infants who presented with frequent vomiting had a significantly higher fractional reflux time than infants who had infrequent or no vomiting. There was no significant association between abnormal chest x rays and pathological GOR. Sex, genotype, nutritional status, meconium ileus, and pancreatic enzyme supplementation were not significantly associated with pathological GOR. CONCLUSIONS: About one in five newly diagnosed infants with cystic fibrosis had pathological GOR. Pathologically increased reflux was present before radiological lung disease was established. Apart from frequent vomiting, no useful clinical predictors of pathological reflux were found.     

The European Sero-Epidemiology Network: standardizing the enzyme immunoassay results for measles, mumps and rubella

The ESEN (European Sero-Epidemiology Network) project was established to harmonize the seroepidemiology of five vaccine preventable infections including measles, mumps and rubella in eight European countries. This involved achieving comparability both in the assay results from testing in different centres and also sampling methodology. Standardization of enzyme immunoassay results was achieved through the development of common panels of sera by designated reference centres. The panels were tested at the reference laboratory and then distributed to each participating laboratory for testing using their routine methods. Standardization equations were calculated by regressing the quantitative results against those of the reference laboratory. Our study found large differences in unitage between participants, despite all using an EIA method standardized against an international or local standard. Moreover, our methodology adjusted for this difference. These standardization equations will be used to convert the results of main serosurvey testing into the reference country unitage to ensure inter-country comparability.     

Segmental biliary obstruction: false-negative diagnosis with direct cholangiography without US guidance

Segmental intrahepatic ductal obstruction with calculi can be a significant cause of acute cholangitis that may remain entirely undetected on a routine, "blind" direct cholangiogram. Ultrasonography (US) or computed tomography can demonstrate isolated intrahepatic ductal dilatation with or without calculi. US, in particular, can be used to direct the needle puncture for percutaneous transhepatic cholangiography (PTC) and thus enable the differential diagnosis and appropriate therapy to be determined. Four cases are reported in which US-guided PTC enabled confirmation of the diagnosis of acute cholangitis secondary to segmental biliary obstruction and intrahepatic calculi. In two the correct diagnosis could not be made with initial blind direct cholangiography, and in the other two, US and US-guided PTC were performed initially.     

Removal of the Outer Table of the Skull for Reconstruction of Full-Thickness Scalp Defects with a Dermal Regeneration Template

BACKGROUND The reconstruction of large defects of the scalp after wide excisional surgery of cutaneous malignancies is challenging. When the pericranium must be resected due to safety considerations, the exposed bone complicates reconstructive approaches.
OBJECTIVE The objective was to develop an improved technique for reconstructive surgery of full-thickness scalp defects.
METHODS Full-thickness scalp defects of up to 126 cm² in size with exposure of denuded bone were treated by partial removal of the outer table of the skull. The diploic space exposed by this treatment showed petechial bleeding and was covered with a dermal regeneration template (Integra, Integra Lifesciences Corp., Plainsboro, NJ). After transformation of the template by vascularization and by proliferation of fibroblasts, an ultrathin skin graft was transplanted onto the neodermis.
RESULTS Thirteen patients with cutaneous malignancies of the scalp were treated using this technique. The defects were transplanted within a median postoperative time period of 29 days (± 4 days) and showed good cosmetic results and stable scars. After a follow-up period of 6 months, no local recurrences were observed.
CONCLUSION This reconstructive procedure allows closure and rapid healing of large scalp defects in which the pericranium had to be resected.