The formation of Ca++-dependent complexes of platelet membrane glycoproteins IIb and IIIa in solution as determined by crossed immunoelectrophoresis

Triton X-100 soluble proteins from 125I-labeled human platelets were studied by crossed immunoelectrophoresis employing a multispecific rabbit antibody raised against whole normal platelets. Emphasis was placed upon an analysis of immunoprecipitates containing 125I-labeled major membrane glycoproteins, and in particular, a prominent immunoprecipitate containing a glycoprotein antigen (s) previously designated as protein 16. SDS-polyacrylamide gel electrophoresis of protein 16 precipitated by a monospecific alloantibody. IgG L . . . , confirmed the presence of both glycoproteins IIb and IIIa. 125I-IgG L . . . , at concentration below that capable of precipitating protein 16 by itself, bound specifically to the precipitate containing protein 16 produced by the multispecific rabbit antibody. No other precipitates formed by the rabbit antibody contained either glycoprotein IIb or IIIa. When platelet proteins, incubated with optimum concentrations of ethylenediamine tetraacetic acid (EDTA) or ethyleneglycol bis (B- aminoethylether) NN1-tetraacetic acid (EGTA), were electrophoresed against the rabbit antibody, previously unobserved immunoprecipitates that contained either free glycoprotein IIb or free glycoprotein IIIa were detected. Upon readdition of excess Ca++, but not Mg++, to the same protein samples, a single immunoprecipitate containing both glycoproteins was once again observed. It is thus demonstrated that glycoproteins IIb and IIIa can form Ca++-dependent complexes (protein 16) in Triton X-100 extracts of normal platelets. The potential significance of the reversible association of these glycoproteins to normal platelet function is discussed.     

Surface shield: device to reduce personnel radiation exposure

A simple device is described that can reduce personnel exposure from scatter radiation by up to 75%. The device consists of an oblong piece of shielding (0.75-mm lead equivalent) that is taped to the side of the patient during percutaneous renal stone removal and other interventional procedures. Contrary to other shields and barriers, this does not interfere with access to the patient. Scatter exposure data from phantom studies are presented and the rationale for surface shielding discussed.     

Comparison of weekly and daily incremental protocols of narrowband ultraviolet B phototherapy for psoriasis

BACKGROUND: Different protocols have been used for narrowband ultraviolet B (UVB) therapy, commonly used in the treatment of psoriasis; however, more effective and reliable protocols are still required. OBJECTIVE: The aim of this study was to compare the weekly and daily dose increment protocols of narrowband UVB phototherapy in psoriasis patients. METHODS: Thirty patients with plaque psoriasis underwent narrowband UVB treatment three times a week and 15 patients selected consecutively among these patients underwent a weekly (once in three treatments) dose increment whereas the remaining 15 patients underwent a daily dose increment. Patients were monitored for 10 weeks and evaluated by the Psoriasis Area Severity Index (PASI). RESULTS: When the two groups were evaluated according to median PASI scores prior to the treatment and during 10 weeks of treatment, there was no statistically significant difference between the groups (P > 0.05). During the treatment lasting for 10 weeks, four patients in the group with a weekly dose increment and three patients in the group with a daily dose increment recovered and no statistically significant difference was detected between the groups (P > 0.05). The groups were also evaluated according to the median cumulative dose. The median cumulative dose was higher in the group with a daily dose increment and the difference between the groups was statistically significant (P = 0.002). CONCLUSION: The application of daily dose increments was no better than that of weekly dose increments in narrowband UVB treatment for psoriasis. Therefore, although our results may need to be supported by large-series studies, we conclude that application of weekly dose increments with a lower cumulative dose having the same efficacy is preferred in narrowband UVB treatment of psoriasis.     

Clinical and cerebrospinal fluid findings in lymphocytic meningo-radiculitis (Bannwarth's syndrome)

11 patients with lymphocytic meningo-radiculitis (Bannwarths syndrome) are described. The disease is characterized by intensive pain, often radiating and migrating, and neurological deficits, i.e. peripheral facial palsies, as well as disseminated radiculopathies. In 4 patients the onset was preceeded by an arthropode bite, close to which 3 patients exhibited an erythema chronicum migrans.
In the cerebrospinal fluid there was a mononuclear pleocytosis, predominately by lymphocytes. In the early stages, a plasma cell reaction was frequently encountered. Protein analysis indicated a defect in the blood brain barrier and an intrathecal synthesis of IgG.
All patients recovered almost completely from their neurological symptoms within 1–2 months, irrespective of treatment.     

Thrombosed synthetic hemodialysis access fistulas: failure of fibrinolytic therapy

Seven episodes of acute thrombosis occurring in five patients with polytetrafluoroethylene dialysis fistulas were treated with local infusions of low-dose streptokinase. Bleeding from previous dialysis puncture sites necessitated stopping the infusion in six out of seven patients, although in one of these six, the graft reopened. The seventh patient had never been dialyzed through the graft and thrombolysis was achieved without incident. Surgery was avoided in only one patient. The authors contend that in these patients the risks of fibrinolytic therapy outweigh the benefits. Surgical thrombectomy, coupled with intraoperative angiography and possible angioplasty, is the preferred method of treating these patients. Venography prior to the creation of the fistula helps the surgeon avoid diseased vessels and may avert early failure of the fistula.     

Multiple sclerosis: Search for a serologic inhibitor

Complement-fixing (CF) antibrain antibodies are frequently found in serum and CSF in multiple sclerosis (MS). A negative result in the test for these antibodies migh depend not only on a lack of antibodies, but also on serologic inhibiting factors. To test this possibility, serum and concentrated CSF samples without demonstrable CF antibrain antibodies were allowed to interact with two standardized positive complement fixation reactions; one for antibrain antibodies and the other a Wasserman reaction. No evidence of inhibiting activity was found in 11 CSF and 15 serum samples from 20 MS patients. On the other hand, inhibiting activity was seen in serum from four of 12 patients with neoplasms and from three of 11 patients with rheumatoid arthritis.