A Rare Cause of Persistent Blood Loss after Continuous Ambulatory Peritoneal Dialysis Catheter Placement.

The laparoscopic placement of a continuous ambulatory peritoneal dialysis (CAPD) catheter is a widely used method in patients with end stage renal disease (ESRD). The potential complications of this procedure include perforation of intra-abdominal organs, surgical site infection, peritonitis, catheter migration, catheter blockage, port site herniation, and bleeding. In most cases, bleeding is considered to be an early-onset complication because it mostly occurs within the first seven days after surgery. We report a case of a 68-year-old female patient with a previous history of diabetes mellitus, myelodysplastic syndrome, extensive collateral varices, anaemia, and ESRD due to obstructive uropathy caused by retroperitoneal fibrosis, who presented with persistent blood loss after the laparoscopic placement of a CAPD catheter. Duplex ultrasonography showed that the CAPD catheter was transfixing a superficial epigastric varicose vein, a collateral vein, due to the occlusion of the left external iliac vein. Persistent blood loss after inserting a CAPD catheter without previous imaging of abdominal wall vessels is an indication for further diagnostics.

Mechanism of anti-HIV activity of succinylated human serum albumin.

In the present study, we described the interaction of succinylated human serum albumin (Suc-HSA), a negatively charged anti-HIV-1 active protein, with HIV-1 gp120 and in detail with the third variable domain of gp120 (V3 loop). To this end, different assay formats were tested in which gp120- and V3-related peptides were presented in various configurations in order to investigate the effect of the conformational structure of the V3 loop on the interaction with negatively charged albumins. When gp120 presented via a lectin was used, it was observed that Suc-HSA bound to native gp120. The binding site appeared to be located at or near the thrombin digestion site (GPGRAF sequence) in the V3 loop of gp120, since the cleavage of the loop resulted in decreased binding of Suc-HSA. In addition, Suc-HSA was able to protect the V3 region of gp120 from cleaving with thrombin. In contrast, significant binding of Suc-HSA to V3 loop or gp120 peptides was not observed when both were presented in a fluid phase system, suggesting the involvement of a monovalent-low affinity binding of Suc-HSA. Using overlapping peptides delineating the whole V3 loop immobilized to CNBr-Sepharose, we noticed that the interaction of the V3 loop with Suc-HSA was predominantly induced by electrostatic interactions between positively charged linearized peptide fragments and Suc-HSA and was positively influenced by the presence of hydrophobic amino in the V3 loop fragments as well. Moreover, the highest affinity site was located at sites near the GPGRAF sequence. These observations add to the evidence, collected earlier, that Suc-HSA interferes at the level of virus entry, independent of interaction with the CD4 receptor. Since the recently discovered chemokine receptors are negatively charged, we can hypothesize that Suc-HSA is able to prevent the positively charged V3 loop from interacting with these types of receptors, thereby inhibiting virus entry.

Recurrent herpetic keratitis in penetrating keratoplasty.

In a retrospective study we evaluated 49 consecutive penetrating keratoplasties for herpes simplex keratitis. Mean follow-up was 44.2 months. Survival analysis with Kaplan-Meier curve showed an overall survival rate (clear graft) of 88% at one year, 76% at two years and 72% at four years postoperatively. Survival analysis showed a recurrence-free survival rate of 72% at one year, 59% at two years and 51% at four years postoperatively. Of the 13 non-primary graft failures, 9 happened in eyes with an HSV recurrence. Recurrence of HSV infection occurred in 18 (39%) eyes at an average of 12.6 months after surgery (range 0.3-46). Five (28%) of the recurrences occurred within two months after the start of steroid treatment for rejection. Nine (50%) of the recurrences cases resulted in a clouded graft at the end of follow-up. 73% of the eyes with a clear graft had a VA of 0.25 or better. We conclude from these data that a recurrence of a herpetic infection following corneal transplantation is the main reason for graft failure in this group.

The separation of bovine prothrombin and descarboxyprothrombin by high-performance liquid chromatography.

Prothrombin contains 10 gamma-carboxyglutamic acid (Gla) residues which are absent in the warfarin-induced descarboxyprothrombin; hence prothrombin has 10 more negative groups than has descarboxyprothrombin. The two proteins can be separated by HPLC with the aid of an anion-exchange column. Plasma from warfarin-treated animals could be analyzed without pretreatment of the samples and a full analysis was obtained in 30 min.

Warfarin-induced accumulation of vitamin K-dependent proteins. Comparison between hepatic and non-hepatic tissues.

At high concentrations (7.5 mg/kg body weight), coumarin derivatives inhibit the vitamin K-dependent carboxylation reaction in hepatic as well as in non-hepatic tissues. Therapeutically this anti-vitamin K drug is frequently used in 100-fold lower dosages. Under these conditions the production of the vitamin K-dependent clotting factors in the liver is only partially inhibited. Using the rat as an experimental animal, we could demonstrate, that during a daily intake of these low amounts of warfarin, endogenous substrates for vitamin K-dependent carboxylase accumulate in the lung, spleen and testis in a similar way as they do in liver. Therefore it seems that in vivo the carboxylating enzyme systems in all these tissues are inhibited. It seems plausible, that this effect of warfarin is not restricted to rats, but that it will also occur in patients under anticoagulant therapy.