Multivesicular bodies are an intermediate stage in the formation of platelet alpha-granules

We have used ultrathin cryosectioning and immunogold cytochemistry to study the position of alpha-granules in the endocytic and biosynthetic pathways in megakaryocytes and platelets. Morphologically, we distinguished three types of granules; so-called multivesicular bodies type I (MVB I) with internal vesicles only, granules with internal vesicles and an electron dense matrix (MVB II), and the alpha-granules with mainly a dense content and often internal membrane vesicles at their periphery. The MVBs were prominent in cultured megakaryocytes and the megakaryoblastic cell line CHRF-288, but were less numerous in bone marrow megakaryocytes and platelets, whereas alpha-granules were most prominent in mature bone marrow megakaryocytes and in platelets. The internalization kinetics of bovine serum albumin-gold particles and of fibrinogen positioned the MVB subtypes and alpha-granules sequentially in the endocytic pathway. MVBs contained the secretory proteins von Willebrand factor (vWF) and beta-thromboglobulin (beta-TG), the platelet-specific membrane protein P-selectin, and the lysosomal membrane protein CD63. Within the MVBs, endocytosed fibrinogen and endogenous beta-TG were restricted to the matrix, while vWF was predominantly associated with internal vesicles. CD63 was also observed in association with internal membrane vesicles in the alpha-granules. These observations, and the gradual morphologic transition from granules containing vesicles to granules containing predominantly dense material, suggest that MVBs represent a developmental stage in alpha-granule maturation.     

Homozygous deletion of the p16INK4A gene occurs more frequently in CD2+ than in CD2+ T-cell acute lymphoblastic leukemia

Right ventricular assist devices are an important part of the armamentarium of cardiac surgeons for the treatment of right-sided circulatory failure after cardiac transplantation or insertion of a left ventricular assist device. However, right ventricular assist device insertion can be technically challenging in the setting of pulmonary hypertension because of a number of concomitant anatomic and physiologic phenomena. We present a technique for the insertion of the right ventricular assist device outflow cannula that is easier and faster to insert, and safer to explant, especially if cardiopulmonary bypass is to be avoided.     

Childhood Lead Poisoning in Russia: A Site-specific Pediatric Blood Lead Evaluation

The association between the actual status of cryoglobulins (CGs) expression in hepatitis C-related chronic liver disease (C-CLD) and different types of liver pathology, HCV-RNA titers and genotypes was investigated. Sixteen out of 1340 ordinary clinical specimens were CGs-positive (1%), and in 8 of them (50%) the patients blood was HCV-RNA positive. CGs was detected in 63% of C-CLD patients as a whole, but when compared with the histological findings in the liver, it was 88% in F3, and 92% in A3, and thus high percentages were detected in patients with progression of liver fibrosis and patients with strong activity. Serum IgG, IgM, transaminase and gamma-GTP levels were significantly higher in the patients with CGs, and their RA test and C3dCIC levels tended to be higher, but the differences were not significant, and no association was found with the anti-nuclear antibody positive level, or the HCV-RNA titers or genotypes. Based on the above, there was a clear involvement of HCV infection, especially the activity and histological progression of hepatitis in CGs formation in Japan as well, but there were few extrahepatic manifestations, suggesting differences in CGS levels and immune response to CGs from cases in Western countries.     

2',3'-cyclic nucleotide 3'-phosphodiesterase: a novel candidate autoantigen in demyelinating diseases

Autoaggressive T-cells specific for myelin proteins like proteolipid protein (PLP) and myelin basic protein (MBP) are thought to play a major role in the pathogenesis of demyelinating diseases of the central nervous system (CNS). 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) is the third most abundant myelin protein in the CNS. Due to lack of supply with enough CNPase of sufficient purity its immunologic properties have not been studied yet. We subcloned a human CNPase cDNA and expressed human recombinant CNPase (rh-CNPase) in E. coli. Purification of the protein was achieved by Ni(2+)-chelating chromatography. Furthermore we describe for the first time several rh-CNPase specific T-cell lines from a multiple sclerosis patient and a healthy control.     

Osteocalcin expression in young and aged dental pulps as determined by RT-PCR

OBJECTIVE: To determine the effect of intramuscular gold and oral hydroxychloroquine (HCQ) on the lipid profile of patients with rheumatoid arthritis (RA). METHOD: A prospective randomised clinical trial of 12 months' duration was performed in 100 RA patients. Data on clinical and laboratory parameters of disease activity, and fasting serum lipid samples was collected at baseline and at three monthly intervals over one year. RESULTS: The expected second line response was seen with no significant difference in efficacy between the groups at 12 months. The HCQ group had a significant overall improvement in their lipid profile while there was a trend for lipid profiles in the gold group to worsen. CONCLUSIONS: HCQ is an effective second line agent that has beneficial effects on serum lipids. This should be taken into account when choosing a disease modifying anti-rheumatic drug in patients who suffer from RA and who have significant cardiovascular risk factors.     

An early marker for neurological deficits after perinatal brain lesions

BACKGROUND: In normal awake infants, fidgety movements are seen from the age of 6 weeks to 20 weeks. The aim of the study was to test the predictive value of absent or abnormal spontaneous movements in young infants for the later development of neurological deficits. METHODS: In a collaborative study involving five hospitals we collected data on the normal and abnormal quality of fidgety movements of 130 infants and compared it with assessments of neurological development done longitudinally until the age of 2 years. On the basis of ultrasound scans infants were classified as at low-risk or at high-risk of neurological deficits. Infants were videoed for 1 h every week from birth to discharge and then for 15 min every 3 to 4 weeks; quality of general movements was assessed. Repeated neurological assessments were also done until 24 months of corrected age. FINDINGS: 67 (96%) of 70 infants with normal fidgety movements had a normal neurological outcome. Abnormal quality or total absence of fidgety movements was followed by neurological abnormalities in 57 (95%) of the 60 infants (49 had cerebral palsy and eight had developmental retardation or minor neurological signs). Specificity and sensitivity of fidgety movement assessment were higher (96% and 95%, respectively) than of ultrasound imaging of the infants' brain (83% and 80%, respectively). INTERPRETATION: Our technique of assessing spontaneous motor activity can identify and distinguish between those infants who require early intervention for neurological abnormalities and those who do not. Our technique is simple, non-intrusive, reliable, quick, and can be done on very young infants.     

Growth of P511 mastocytoma cells in BALB/c mouse brain elicits CTL response without tumor elimination: a new tumor model for regional central nervous system immunity

We have developed a murine model to explore the tumor-specific CTL response in the immune-privileged central nervous system using P511 mastocytoma cells. Three strains with varying degrees of histocompatibility to P511 cells (CD-1, allogeneic; BALB/c, minor histoincompatible; DBA/2, syngeneic) received tumor cells (10(4)) into the putamen 7 days after cannula implantation, when the blood-brain barrier was functionally intact. Without exception, tumor formed reproducibly by day 7 in all strains. Tumor rejection occurred in CD-1 but not in BALB/c and DBA/2 mice. Using a flank injection site, both CD-1 and BALB/c, but not DBA/2 mice, ultimately rejected flank tumors. Analysis of tumor-specific CTL in BALB/c spleens revealed that P511 administration into brain or flank elicited similar responses: no fully activated CTL were detectable but a significantly expanded population of nonkilling precursors of CTL (pCTL) were present. A P511 cell-specific pCTL population was also identified at the brain tumor site 14 days post-tumor introduction, indicating that pCTL, generated in the periphery, traffic to the tumor site in brain. These data indicate that failure to reject tumor in brain is neither due to lack of afferent stimulation nor to inability of peripheral effectors (P511 cell-specific pCTL) to reach the tumor site. We hypothesize that these effector cells are prevented from developing into fully activated CTL by conditions within the central nervous system microenvironment that down-regulate CTL development.     

Identification of a new all-trans-retinol metabolite produced through a new retinol metabolic pathway

In vitro incubation of all-trans-retinol (atROL) with kidney homogenate from vitamin A-deficient and retinoic acid-supplemented (VAD-RAS) female rats produces a new retinol metabolite. Reverse-phase (RP) and normal-phase (NP) high-performance liquid chromatography (HPLC) analysis showed that this metabolite coelutes with the unknown all-trans-retinol (atROL) metabolite previously found in the day 10 conceptus and kidneys of vitamin A-deficient rats maintained on all-trans-retinoic acid (VAD-RA) and given 2 microg of [3H]atROL. Normal-phase (NP) HPLC purification of the metabolite collected from a RP HPLC column further separated the radiolabeled material into two components. The two isolated compounds have identical or very similar spectroscopic properties. Their nuclear magnetic resonance (1H NMR) and mass spectra (MS) indicated that they are isomers. Spectroscopic studies of the metabolites and their derivatives showed that they are nine-carbon fragments resulting from an oxidative cleavage of the side chain of atROL. The cleavage occurs at C-9, and the product is then oxidized to a keto group. The primary hydroxy group from atROL is preserved in the metabolite. A sulfide bridge is formed between C-11 and C-14, which interrupts the conjugation. The formation of the new metabolites, possessing a 2,5-dihydrothiophene ring, is catalyzed by an enzyme(s) located in the cytosolic fraction of kidneys. The process represents a new retinol metabolic pathway; however, its biological significance is unknown.