Race/ethnicity and gender differences in the drugs-violence relationship

This article examines the drug relatedness of violent events reported by White, Black, and Hispanic male and female street drug users from New York City. The primary purpose is to determine if the drugs-violence relationship varies for these different populations of drug abusers. Drug relatedness is assessed according to a tripartite conceptual model of the general relationship between drugs and violence. Significant race/ethnicity and gender differences were found in regard to the number of violent events manifesting specific drug-related dimensions of violence, the drugs associated with these violent events, and the primary reasons for the occurrence of these events. The implications of these findings are discussed.     

Asymptomatic autoimmune chronic active hepatitis in a male adolescent

We report a 12-year-old boy presenting with smooth muscle antibody-positive auto-immune chronic active hepatitis. Suspicion of the diagnosis arose after a routine blood test which revealed abnormal liver function tests. In spite of the presence of cirrhosis and patchy necrosis on liver biopsy, our patient never showed any clinical feature of impaired liver function. This observation demonstrates that auto-immune hepatitis may exist for a long time before clinical symptoms appear and probably explains why some cases of auto-immune hepatitis finally present as fulminant liver failure.     

Mechanical behaviour of articular cartilage under tensile cyclic load.

INTRODUCTION: Although fatigue has been implicated in cartilage failure, there are only two published studies in this area, by the same author. However, in these previous studies cartilage was tested in the direction parallel to that of collagen orientation in the superficial layer, where it possesses greater tensile strength. In the present work, articular cartilage was also tested along the direction perpendicular to that of the collagen. Furthermore, the study investigated topographic and zonal variations in the fatigue behaviour of cartilage from the human knee. METHODS: Specimens were tested in a specially constructed apparatus that allowed the number of cycles at specimen failure, as well as the load and elongation of the specimen, to be monitored for each specimen. To date, some 72 specimens have been tested, all from the same knee joint, though from different sites and at different depths within the cartilage layer. RESULTS AND CONCLUSIONS: The most impressive of the outcomes of this study is the scatter of the data. Considering all the specimens used, the range of number of load cycles to failure was between 2 and 1.5 million. The zonal variation in fatigue behaviour was similar to that in tensile modulus reported previously; the surface and deep layers seemed to have better fatigue properties whether tested in the direction parallel or perpendicular to that of the collagen in the superficial layer. The middle layer was far weaker, suggesting that highly packed and ordered fibres in the surface and deep zones have better mechanical properties than the more random and loose fibres in the middle zone. The variation in fibre organization through the cartilage thickness was also reflected in the differences observed in the elongation of the specimen during the test. The surface and deep zones had a higher stiffness than the middle zone. Cartilage had better fatigue resistance when the specimen was loaded in a direction parallel rather than perpendicular to the collagen within the surface layer. This was true whether specimens were harvested from the superficial, intermediate or deep layer. There were many factors that confounded attempts to estimate the likely fatigue life from the data obtained in such a study.     

A defect of platelet aggregation associated with an abnormal distribution of glycoprotein IIb-IIIa complexes within the platelet: the cause of a lifelong bleeding disorder.

A young Italian man (A.P.) has a lifelong history of bleeding from gums and mucocutaneous tissue. Electron microscopy showed a wide diversity of platelet size including giant forms. In citrated platelet-rich plasma (PRP), platelet aggregation induced by adenosine diphosphate (ADP) and other agonists was much reduced. Both secretion and clot retraction were normal. The aggregation of washed platelets with ADP was improved but remained subnormal, as was aggregation with collagen and thrombin. Fibrinogen-binding was analyzed by flow cytometry using platelets in whole blood or PRP and was markedly decreased. Crossed immunoelectrophoresis of Triton X-100 extracts of (A.P.) platelets showed that GP IIb-IIIa levels were 40% to 50% of normal. Glycoprotein (GP) IIb and GP IIIa were of usual migration in sodium dodecyl sulfate-polyacrylamide gel electrophoresis, but their labeling was much reduced during lactoperoxidase-catalyzed iodination. Binding to (A.P.) platelets of four different 125I-labeled monoclonal antibodies to GP IIb-IIIa complexes was reduced to 12% to 20% of normal levels. However, when the patient's platelets were stimulated with alpha-thrombin, monoclonal antibody binding showed the same increase (approximately 20,000 sites) as normal platelets. Both flow cytometry and immunocytochemical studies showed that the distribution of residual surface GP IIb-IIIa within the total (A.P.) platelet population was heterogeneous and not related to platelet size. Staining of ultrathin sections confirmed the presence of an internal pool of GP IIb-IIIa. Monoclonal antibodies to other membrane glycoproteins bound normally to (A.P.) platelets. The patient has a selective deficiency of the surface pool of GP IIb-IIIa complexes that is manifested clinically by a mild Glanzmann's thrombasthenia-like syndrome.     

Novel optimized biopolymer-based nanoparticles for nose-to-brain delivery in the treatment of depressive diseases

A valid option to bypass the obstacle represented by the blood–brain barrier (BBB) in brain delivery is the use of the unconventional intranasal route of administration. The treatment of depressive diseases, resulting from the depletion of a neurotransmitter in the inter-synaptic space, such as serotonin, is indirectly treated using molecules that can permeate the BBB unlike the latter. In the present article, a set of nanovectors were produced using a mucoadhesive biopolymer, i.e. alginate (Alg). Optimizing the reaction, polymeric nanoparticles having diameter of 30–70 nm were produced, and water stable multi-walled carbon nanotubes functionalized (MWCNT-COOH)/Alg complexes were obtained. These nanovectors were loaded with serotonin, evaluating drug loading/release. By means of Raman microscopy, the cellular internalization of the (MWCNT-COOH)/Alg complex was demonstrated. A complete biocompatibility on neuronal cells was proved for the whole set of nanovectors. Finally, a method of self-administration was tested, which involves the use of a household apparatus, such as an aerosol machine, observing a fine particulate, able to deliver the nanovectors through the nose.

A valid option to bypass the obstacle represented by the blood–brain barrier (BBB) in brain delivery is the use of the unconventional intranasal route of administration.     

Healing and prevention of relapse of reflux oesophagitis by cisapride.

Altogether, 138 patients were included in a study aimed at evaluating the effect of cisapride on healing and relapse of oesophagitis shown endoscopically. In the first phase of the study cisapride was given in an open fashion at 10 mg four times a day for 8 to 16 weeks, and healing was obtained in 69% of patients. Healing occurred later in patients with grades II to IV oesophagitis. The total score for reflux symptoms decreased by 67%. Eighty of the healed patients were included in the second phase. They were randomly assigned to double blind treatment with either cisapride 10 mg (n = 37) or placebo (n = 43) twice a day. Control endoscopy was performed when symptoms recurred or at the end of the six month trial. The cumulative percentage of patients in remission was higher (p = 0.06, survival analysis) in the cisapride group than in the placebo group, the relapse rates being 20% and 39%. The duration of remission tended to be longer in patients with a lower initial degree of oesophagitis. Adverse effects were no more frequent with cisapride than with placebo. In conclusion, cisapride is efficacious in healing oesophagitis, and, unlike other gastrointestinal prokinetic drugs or low dose cimetidine (400-800 mg daily) or ranitidine (150 mg daily), it may prevent relapse of oesophagitis.     

Graft-versus-tumor response in patients with multiple myeloma is associated with antibody response to BCMA, a plasma-cell membrane receptor

Donor lymphocyte infusions (DLIs) induce effective graft-versus-tumor responses in patients with multiple myeloma who relapse after allogeneic hematopoietic stem-cell transplantation. The graft-versus-myeloma response is presumably mediated primarily by donor T cells, but recent studies have also demonstrated the presence of antibodies specific for a variety of myeloma-associated antigens in patients who achieve complete remission after DLI. One of the B-cell antigens identified in these studies was B-cell maturation antigen (BCMA), a transmembrane receptor of the tumor necrosis factor (TNF) superfamily that is selectively expressed by mature B cells. The present studies were undertaken to characterize the functional significance of antibodies to BCMA in vivo. Using transfected cells expressing BCMA, antibodies in patient serum were found to react with the cell-surface domain of BCMA. Post-DLI patient serum was able to induce complement-mediated lysis and antibody-dependent cellular cytotoxicity (ADCC) of transfected cells and primary myeloma cells expressing BCMA. BCMA antibodies were only found in post-DLI responders and not in other allogeneic transplant patients or healthy donors. These results demonstrate that BCMA is a target of donor B-cell immunity in patients with myeloma who respond to DLI. Antibody responses to cell-surface BCMA may contribute directly to tumor rejection in vivo.     

Basic fibroblast growth factor: effects on matrix remodeling, receptor expression, and transduction pathway in human periosteal fibroblasts with FGFR2 gene mutation.

The Crouzon syndrome, which is associated with fibroblast growth factor receptor (FGFR2) mutations, is characterized by premature fusion of cranial sutures. We used an in vitro model of cultured periosteal fibroblasts from normal subjects and from Crouzon patients with FGFR2 mutation. We analyzed the matrix turnover rate and the effects of adding FGF2 by evaluating fibronectin synthesis and the activity of some proteolytic enzymes. To assess the role of some FGF signaling molecules involved in FGFR2 regulation, we studied Grb2 tyrosine phosphorylation and the phosphotyrosine proteins associated with Grb2. The iodinate FGF binding assay was performed to quantify FGFR expression. Compared with normal fibroblasts, fibronectin synthesis was decreased in Crouzon fibroblasts, and protease activities in cells and medium were enhanced, suggesting that excess fibronectin catabolism is present. Differences were more marked when FGF2 was added. Very few phosphoproteins were visible in anti-Grb2 immunoprecipitations from Crouzon fibroblasts, which showed a significant increase in the number of high-affinity and low-affinity FGF2 receptors. These results suggest that the abnormal genotype and the Crouzon cellular phenotype are related. To compensate the low levels of tyrosine phosphorylation, Crouzon cells might increase the numbers of FGFR2, thus increasing the cell surface binding sites for FGF2.