Choledochoscopic stone removal through a T-tube tract: experience in 75 consecutive patients

Retained biliary stones remain a common clinical problem in patients after surgery. Since 1984, the authors have used choledochoscopy in the treatment of suspected retained biliary stones in 75 patients. These procedures were performed in the radiology department with use of local anesthesia supplemented by an intravenously administered sedative and analgesic. A 15-F flexible fiberoptic choledochoscope was used. Fifty-one of the 75 patients were treated as outpatients. Treatment was successful in 74 of 75 patients; in one patient, intrahepatic stones were not completely removed. Electrohydraulic lithotripsy was used to fragment calculi in 11 patients (15%). Biopsies were performed in four patients (5%). Five minor complications occurred; three required overnight admission. Choledochoscopic-assisted removal of retained biliary calculi is a highly effective and safe procedure. Advantages over standard fluoroscopic stone removal include the ability to directly visualize and fragment adherent or impacted stones and visualize noncalculous filling defects, such as air bubbles, mucus, and biliary tumors.     

Managing self-injection difficulties in patients with relapsing-remitting multiple sclerosis.

Difficulties with self-injection, including inabillity to self-inject, are common for individuals taking home-administered injectable medications. In relapsing-remitting multiple sclerosis (MS), all of the currently available disease-modifying medications are injectables marketed for self-injection. Problems with self-injection pose a barrier to treatment adherence for many patients. Clinicians at the University of California, San Francisco (UCSF) Multiple Sclerosis Center have developed a number of strategies to help patients who experience anxiety associated with self-injection. These strategies have been empirically tested and found to be effective and easily implemented by mental health professionals and nurses. This article offers case examples and discussion of the principles of the techniques developed at UCSF to remediate patients' difficulties with self-injection. Nurses are most often the healthcare providers responsible for training MS patients in self-injection and monitoring their compliance. Nurses who are familiar with these tools have the opportunity to have a significant positive impact on patient comfort, confidence, and, ultimately, successful long-term adherence to disease-modifying medications.     

Identification of T cell epitopes within a 23-kD antigen (P24) of Toxoplasma gondii.

Among the potentially vaccinating antigens, the products excreted/secreted by the parasite T. gondii have been demonstrated to be excellent candidates. The molecular cloning of one of these antigens (P24) present in excreted/secreted antigens (ESA) has recently been carried out in our laboratory. The recombinant antigen P24 corresponds to a native molecule of 23 kD. We were interested in determining the main epitopes of the P24 antigen eliciting a T lymphocyte response using synthetic peptides derived from the primary structure of P24. Five peptides: 64-79, 88-109, 170-193, 194-208 and 231-250 were synthesized according to their hydrophobicity, mobility and accessibility profiles. The presence of T lymphocyte epitopes in these peptides has been examined in the rat model. The determination of T cell epitopes was carried out using T lymphocytes from infected rats, and from ESA and P24 expression vaccine virus immunized rats. The results showed that the stimulation of T cells with these peptides varied according to the period after Toxoplasma infection. The main T cell stimulation was obtained with the 88-109, 170-193 and 194-208 peptides. When Fisher rats were immunized with ESA, a most significant stimulation was achieved with the 170-193 and 194-208 peptides. In addition, T lymphocytes primed with P24 expressed vaccine virus immunization were more stimulated with the 88-109 and the 194-208 peptides. This study showed that P24-derived peptide-specific T cells were elicited in the three experimental situations, although no antibody response against the 23-kD native antigen was evidenced in the Fisher rat model. However, the native antigen (presented by irradiated parasites) can induce a proliferative response of the 170-193 peptide-specific T lymphocytes, confirming that this peptide contains an important T cell epitope. The adoptive transfer into athymic rats of T helper cells recovered from 170-193 peptide-immunized Fisher rat conferred a significant protection to infected nude rats despite the fact that no antibody production was observed.     

The synthesis and localization of alternatively spliced fibronectin EIIIB in resting and thrombin-treated megakaryocytes

There are several species of alternatively spliced fibronectin (FN). One of these, FN EIIIB, is primarily present in embryonic and in proliferating and migrating cells and is believed to be important for cell maturation. We have studied the synthesis, localization, and secretion of this FN isoform in isolated guinea pig megakaryocytes, nonmegakaryocytic bone marrow cells, and platelets. There was 7.5 times more general FN in megakaryocytes than in nonmegakaryocytic cells based on the analysis of equivalent amounts of protein. FN EIIIB was detected by Western blotting in megakaryocytes but not in nonmegakaryocytic cells present in bone marrow. Neither megakaryocytes nor platelets secreted FN EIIIB, while megakaryocytes secreted 25.3% +/- 4.6% general FN and platelets secreted about 61% general FN in response to thrombin. Analysis of immunostained cells by confocal microscopy revealed that FN EIIIB had been redistributed to the surface of megakaryocytes in response to thrombin. Synthesis was studied by metabolic labeling, and megakaryocytes were shown to synthesize FN and FN EIIIB. Thus, megakaryocytes and platelets are among a small number of adult cells and tissues that synthesize and contain FN EIIIB. The expression of FN EIIIB on the megakaryocyte surface may influence migration and maturation.