Preoperative biliary drainage, colonisation of bile and postoperative complications in patients with tumours of the pancreatic head: a retrospective analysis of 241 consecutive patients

OBJECTIVE: To analyse the outcome of preoperative biliary drainage in patients being operated on for a tumour in the pancreatic head. DESIGN: Retrospective study. SETTING: University hospital, The Netherlands. SUBJECTS: Consecutive series of 241 patients. MAIN OUTCOME MEASURES: Decline in bilirubin concentrations and bacterial contamination of bile as a result of preoperative drainage. Incidence of postoperative complications in patients who underwent preoperative drainage and those who did not. RESULTS: 184/241 patients underwent preoperative biliary drainage. Endoscopic drainage was the most effective, shown by a median reduction in bilirubin concentrations of 82%, 74%, and 50% after endoscopic drainage (n = 149), papillotomy (n = 25) and external drainage (n = 10), respectively. Bacterial contamination of bile was significantly more common when an endoprosthesis was used, but did not result in a higher rate of infective complications. 163 Whipple's resections, 33 total pancreatectomies, and 45 biliary-enteric bypasses were performed. 137/241 (57%) patients had postoperative complications. There was no significant difference in the incidence of postoperative complications between patients who had preoperative biliary drainage and those who did not (p = 0.4).     

Mature T cell reactivity altered by peptide agonist that induces positive selection

Recent studies have investigated how defined peptides influence T cell development. Using a T cell receptor-transgenic beta2-microglobulin-deficient model, we have examined T cell maturation in fetal thymic organ cultures in the presence of various peptides containing single-alanine substitutions of the strong peptide agonist, p33. Cocultivation with the peptide A4Y, which contains an altered T cell contact residue, resulted in efficient positive selection. Several in vitro assays demonstrated that A4Y was a moderate agonist relative to p33. Although A4Y promoted positive selection over a wide concentration range, high doses of this peptide could not induce clonal deletion. Thymocytes maturing in the presence of A4Y were no longer able to respond to A4Y, but could proliferate against p33. These studies demonstrate that (a) peptides that induce efficient positive selection at high concentrations are not exclusively antagonists; (b) some agonists do not promote clonal deletion; (c) positive selection requires a unique T cell receptor-peptide-major histocompatibility complex interaction; and (d) interactions with selecting peptides during T cell ontogeny may define the functional reactivity of mature T cells.     

Echography in congenital intestinal obstruction in newborn infants

The authors used echography in order to reveal typical echographic signs of high and low bowel obstruction in 51 newborns. Although the use of echography often fails to establish the real cause of the bowel obstruction, it allows the determination of its level and in general promotes making the proper diagnosis.     

Biochemical evidence for pathogenicity of rhodopsin kinase mutations correlated with the oguchi form of congenital stationary night blindness

Rhodopsin kinase (RK), a rod photoreceptor cytosolic enzyme, plays a key role in the normal deactivation and recovery of the photoreceptor after exposure to light. To date, three different mutations in the RK locus have been associated with Oguchi disease, an autosomal recessive form of stationary night blindness in man characterized in part by delayed photoreceptor recovery [Yamamoto, S. , Sippel, K. C., Berson, E. L. & Dryja, T. P. (1997) Nat. Genet. 15, 175-178]. Two of the mutations involve exon 5, and the remaining mutation occurs in exon 7. Known exon 5 mutations include the deletion of the entire exon sequence [HRK(X5 del)] and a missense change leading to a Val380Asp substitution in the encoded product (HRKV380D). The mutation in exon 7 is a 4-bp deletion in codon 536 leading to premature termination of the encoded polypeptide [HRKS536(4-bp del)]. To provide biochemical evidence for pathogenicity of these mutations, wild-type human rhodopsin kinase (HRK) and mutant forms HRKV380D and HRKS536(4-bp del) were expressed in COS7 cells and their activities were compared. Wild-type HRK catalyzed light-dependent phosphorylation of rhodopsin efficiently. In contrast, both mutant proteins were markedly deficient in catalytic activity with HRKV380D showing virtually no detectible activity and HRKS536(4-bp del) only minimal light-dependent activity. These results provide biochemical evidence to support the pathogenicity of the RK mutations in man.     

Adsorption of chitin derivatives onto liposomes: optimization of adsorption conditions

A 2(4) factorial design is used to optimize the adsorption conditions of the hydrophilic anionic polyelectrolytes. Carboxymethylchitin (CMC) and Carboxymethyl/Glycolchitin (CO) onto liposomes at physiological ionic strength (I) and pH using phosphate buffered saline (PBS, I = 154 mM, pH = 7.4). Positive ([+]) or high surface affinity liposomes (DSPC:CHOL:DMTAP, 5:4:1), and Neutral ([N]) or low surface affinity liposomes (DSPC:CHOL, 1:1) were used as adsorption surfaces. Results of the calculations of the main effects indicate that polymer molecular weight (mwt), Surface Affinity (S), Number of Adsorption Shots (Sh), Temperature (T), and the combinations mwt x S, mwt x Sh are the most important process parameters. Results of a study conducted at T = 37 degrees C show that no loss occurs from the positive surface at the highest particle concentration, Np = 4.043 x 10(11). Finally, the extent of polymer-induced particle aggregation is decreased when the diameter of the uncoated liposomes is doubled from 0.22 to 0.45 micron. These results are as expected, given the stiffness and the dimensions of the macromolecules.     

Clinico-epidemiological analysis of imported malaria in Donetsk region (1979-1997)

AIM: The study of possibility of reappearance of malaria foci in the Donets region. MATERIALS AND METHODS: 322 cases of imported malaria (IM) in the Donets region registered in 1979-1997 have been analysed clinically and epidemiologically. Malaria was diagnosed in immigrants from and visitors to Africa, Asia and Latin America, malaria-endemic Azerbaidjan, Tadzhikistan, Afghanistan. RESULTS: Late diagnosis of malaria occurred in immigrants and businessmen who got infected during their business trips. Causative agents of malaria imported from Azerbaijan and Asia were resistant to chemoprophylaxis with delagil and primaxine. Clinical forms of IM are described. CONCLUSION: There is a real danger of malaria reappearance in the Donetsk region as the residents are at risk of being infected from late-diagnosis foreign tourists, immigrants, refugees.     

Engagement of ICAM-3 activates polymorphonuclear leukocytes: aggregation without degranulation or beta 2 integrin recruitment

ICAM-3 is a preferred counterreceptor for the leukocyte alpha(L)beta2 integrin. It activates T cells through outside-in signaling, but polymorphonuclear leukocytes (PMN) are reported to be refractory to ICAM-3 stimulation. We found that engagement of ICAM-3 by a mAb (CAL3.10), which binds in the region where alpha(L)beta2 integrin binds, activates PMN homotypic aggregation and adhesion to surfaces. These functional changes were due to ICAM-3 outside-in signaling because aggregation and adhesion were beta2 integrin-dependent, tyrosine kinase and protein kinase C activities were activated, and there was a reorganization of the cytoskeleton. This reorganization and kinase activity was required for ICAM-3-, but not FMLP-, induced aggregation. This is not an Fc-mediated event as an appropriate anti-ICAM-3 F(ab')2 fragment still induced aggregation. Another anti-ICAM-3 Ab (HP2/19), which activates T cells, did not activate PMN. Strikingly, anti-ICAM-3 did not induce degranulation or cause an increase in surface beta2 integrin expression, so adhesion and aggregation were due solely to the activation of the constitutively expressed beta2 integrins. Aggregation in response to ICAM-3, but not FMLP, was compromised at lower cell densities, showing that beta2 integrin recruitment enhances aggregation under suboptimal conditions. We conclude that engagement of ICAM-3 stimulates PMN as well as T cells, but that the appropriate epitope varies between these two cells. ICAM-3 outside-in signaling reorganizes the cytoskeleton without causing degranulation, induces serine and tyrosine kinase activation, and activates existing surface beta2 integrins to a proadhesive state.