Quantitative studies on lysolecithin mediated hemolysis. Benzylated lysolecithin as a probe to study effects of temperature and red cell species on the hemolytic reaction

The slow reacting hemolytic lysolecithin analog 1-octadecyl-2-benzyl-glycero-3-phosphorylcholine has been employed for a detailed study of the process of lysolecithin induced hemolysis. Using a radiolabelled analog we found that the different sensitivities of red cells from different species (chicken, man, cattle) are not paralleled by the binding affinities of lysolecithin. Moreover, lysophosphatide binding to the cells is reduced at low temperatures while the hemolytic activity increases. In contrast to continuous changes of lytic activity and binding between 0 and 37 degrees C, the velocity of the hemolytic reaction with human erythrocytes is extraordinarily fast at 10 degrees C. Experiments in sucrose containing buffer indicated principally different lysis mechanisms below and above 15 degrees C. We have further shown that cells loaded sublytically with the lysolecithin at 37 degrees C undergo spontaneous lysis upon cooling to 0 degrees C. The degree of lysis under these conditions, however, is diminished with increasing amounts of cell-bound lysolipid. Determinations of membrane microviscosities by means of fluorescence polarization revealed some qualitative relations between membrane fluidity and sensitivity to lysolecithin. The data are discussed on the basis of recent reports indicating that lysolecithin-distribution in mixed lipid phases may be heterogeneous depending on lipid composition and temperature.     

Strain of rat skin at constant load (creep experiments): influence of age and desmotropic agents

Creep experiments were performed on skin strips of rats of various ages (4 weeks to 2 years) and of rats treated with prednisolone acetate or D-penicillamine for 10 days. In one specimen of back skin the ultimate load and tensile strength was measured at an extension rate of 5 cm/min. 50 or 25% of the ultimate load was applied to other specimens of the same skin area. Strain (% extension), time until break, and ultimate extension rate were measured in these samples. The constant load was applied either in a continuous or an intermittent manner. The maturation process (up to an age of 1 year) induced an increase of tensile strength and of ultimate strain followed by a decrease due to the ageing process. Time until break was increased and ultimate extension rate was decreased during the whole life span. These values did not show a maximum or minimum. D-Penicillamine decreased tensile strength, decreased the ultimate strain, shortened the time until break at constant load and increased the ultimate extension rate. Prednisolone increased tensile strength and induced some decrease of ultimate strain and time until break. It was concluded that phenomena like creep indicating the viscosity of connective tissue do not resemble those parameters indicating elasticity behaviour.     

A case of abdominal cocoon

Abdominal cocoon is a rare disease of the peritoneum and almost invariably presents as an acute or subacute intestinal obstruction with or without a mass. The etiology of this disease is largely unknown and abdominal cocoon of unknown etiology has been limited to the tropical and subtropical zones and primarily affects young adolescent females. In the temperate zone, only one case has been reported from the United Kingdom, but the patient was also born in Pakistan. No case of abdominal cocoon purely developed in the temperate zone has been reported. Recently, we experienced a case of abdominal cocoon in a 34-year-old female patient(Korean) who had never been abroad. The diagnosis was made postoperatively by reviewing the literature. We herein report this rare condition developed in an unusual geographical location with a brief review of the literature.     

Fine needle aspiration diagnosis of aggressive giant cell tumor of bone. A case report

Giant cell tumors of bone are neoplasms with potential local and systemic aggressiveness. A case of giant cell tumor with radiologic and histologic features suggestive of locally aggressive behavior is reported. Cytologic material was obtained by fine needle aspiration from an intraosseous tumor that destroyed the cortex and from the invaded, adjacent soft tissues. The smears from the osseous aspirate showed the typical cytologic features of giant cell tumor, whereas the invaded tissues had a prominent loss of cohesiveness between mononucleate and giant cells. In addition, mitotic figures in the mononucleate component were noticeable. The differential diagnosis based on clinical and cytologic findings is discussed.     

Anaphylactic reactions to bee-sting challenges in allergic children are not modified by endogenous catecholamines

To investigate the role of basal catecholamine levels and the response of the adrenergic system to expected bee stings, plasma catecholamines were measured before and 1 and 2 min after bee-sting challenges. Twenty-one children (aged 4-15 y) with bee-sting allergies were selected for sequential challenges to establish the need for venom immunotherapy. The time interval between the challenges varied from 2 to 6 wk. Epinephrine, norepinephrine, and dopamine plasma levels were measured using a simultaneous single-isotope radioenzymatic assay. On the first challenge, 33% of the children experienced a normal local reaction, 29% a large local reaction, and 38% a systemic reaction. On the second challenge in 18 out of 21 subjects, 67% experienced a normal normal local reaction, 22% a large local reaction, and 11% a systemic reaction. Epinephrine and norepinephrine plasma levels increased significantly on the first and second challenges. Dopamine plasma levels showed a significant increase on the first challenge only. Plasma catecholamine levels after the second challenge revealed a significant positive correlation between epinephrine increases measured 1 and 2 min after the challenge and the concomitant sting reaction. Basal epinephrine, norepinephrine, and dopamine plasma levels did not differ significantly between patients who experienced different types of sting reactions. Based on our data, we conclude that clinical reactions to in-hospital insect-sting challenges are not affected by early increases in plasma catecholamine levels produced by the expected stress situation.     

Can urine bound diagnostic tests replace cystoscopy in the management of bladder cancer?

PURPOSE: We compare the diagnostic value of NMP22 and BTA stat testing, and QUANTICYT computer assisted dual parameter image analysis to cytology and cystoscopy in patients who had symptoms suggestive of transitional cell cancer or were being followed after treatment for that disease. MATERIALS AND METHODS: We prospectively evaluated voided urine and/or barbotage specimens from 291 patients a mean of 65.2 years old. All voided urine samples were evaluated by quick staining and standard cytology, the BTA stat 1-step qualitative assay (which detects a bladder tumor associated antigen) and the NMP22 test (which detects a nuclear mitotic apparatus protein). In addition, barbotage specimens were evaluated by QUANTICYT computer assisted dual parameter image analysis. All patients underwent subsequent cystoscopy and biopsy evaluation of any suspicious lesion. Sensitivity, specificity, and the predictive value of positive and negative results were determined in correlation with endoscopic and histological findings. RESULTS: In 91 patients with histologically proved transitional cell carcinoma overall sensitivity was 48, 57, 58, 59 and 59% for the NMP22 test, the BTA stat test, rapid staining cytology of barbotage samples, rapid staining cytology of voided urine specimens and image analysis, respectively. For histological grades 1 to 3 underlying transitional cell carcinoma sensitivity was 17, 61 and 90% for urinary cytology, 48, 58 and 63% for the BTA stat test, and 52, 45 and 50% for the NMP22 test, respectively. Specificity was 100% for cytology, 93% for image analysis, 70% for the NMP22 test and 68% for the BTA stat test. CONCLUSIONS: Immunological markers are superior to cytological evaluation and image analysis for detecting low grade transitional cell carcinoma but they have low specificity and sensitivity in grade 3 transitional cell carcinoma. Urine bound diagnostic tools cannot replace cystoscopy.