Genetic characterization of the murine Ym1 gene and identification of a cluster of highly homologous genes

The induction of Fos protein was examined within LHRH neurons of guinea pigs; the aim was to delineate relationships between subgroups of LHRH neurons during an LH surge in a laboratory rodent in which the distribution of LHRH neurons and the presence of a true luteal phase in the reproductive cycle resemble those in primates. Approximately one third of the forebrain population of LHRH neurons was examined in ovariectomized steroid-treated guinea pigs killed either before or during a steroid-induced LH surge. LHRH/Fos double-labeled neurons were more abundant in surging compared to presurge guinea pigs (p = 0.008) and were most abundant within the preoptic area and anterior hypothalamus. Nonetheless, double-labeled LHRH/Fos neurons were observed throughout the remainder of the population of LHRH neurons in surging guinea pigs. A relative loss of LHRH reaction product was detected by image analysis in the LHRH terminals in the median eminence of surging guinea pigs, consistent with augmented LHRH release. Thus, there appears to be a coordinated increase in Fos expression in subgroups of LHRH neurons, more pronounced in rostral, as compared to caudal, regions in guinea pigs killed after the peak of the steroid-induced LH surge.     

Placing a bone graft more posteriorly may reduce the risk of pedicle screw breakage: analysis of an unexpected case of pedicle screw breakage

Studies on collagen in heart are important to understand the pathogenesis of myocardial necrosis and to evaluate cardiac function in infarcted heart. The present study has been undertaken to find out the alterations in collagen types in heart as well as serum proteins during myocardial injury in rats. A decreased collagen content was observed on day one which may be due to increased secretion of collagenase and proteases from inflammatory cells or from the myocardium. The changes noticed in the collagen types (I, III and V) indicated the altered elasticity of the heart. Histological studies were observed to correlate well with the biochemical changes in collagen. Evaluation of myocardial collagen could provide new approaches to the treatment of infarct size reduction.     

The relation between scabies and hypersensitivity to antigens of house dust mites and storage mites

Twenty five non-atopic scabietic patients were examined to estimate their reaction to crude house dust mite Dermatophagoides farinae (D. farinae) and storage mite Tyrophagus putrescentia (T. putrescentiae) antigens. Skin prick testing (SPT) by extracts of both mites antigens showed significant higher positive results in scabietics when compared to non-scabietic control subjects. Moreover, 60% and 56% of scabietic patients showed positive levels of specific anti-D. farinae and T. putrescentia IgE respectively in comparison to 13.4% & 20% of control subjects. A significant difference has been obtained when the total number of positive results were compared to the total number of negative ones. The results revealed that there is an evidence of cross reactivity between Sarcoptes scabiei antigens and extracts of D. farinae and T. putrescentiae, and the hypersensitivity to house dust mite and storage mite antigens was significantly higher in scabietics than in controls. It could be concluded that there is some proof that other mites rather than Sarcoptes scabiei may have a role in the pathogenesis of scabies and the cross reactivity between S. scabiei and house dust mite and storage mite may explain the persistence of symptoms in some cases even after proper treatment of the disease.     

Selective role for beta-protein kinase C in signaling for O-2 generation but not degranulation or adherence in differentiated HL60 cells

A role for protein kinase C (PKC) isotypes is implicated in the activation of phagocytic cell functions. An antisense approach was used to selectively deplete beta-PKC, both betaI- and betaII-PKC, but not alpha-PKC, delta-PKC, or zeta-PKC in HL60 cells differentiated to a neutrophil-like phenotype (dHL60 cells). Depletion of beta-PKC in dHL60 cells elicited selective inhibition of O-2 generation triggered by fMet-Leu-Phe, immune complexes, or phorbol myristate acetate, an activator of PKC. In contrast, neither ligand-elicited beta-glucuronidase (azurophil granule) release nor adherence to fibronectin was inhibited by beta-PKC depletion. Ligand-induced phosphorylation of a subset of proteins was reduced in beta-PKC-depleted dHL60 cells. Phosphorylation of p47(phox) and translocation of p47(phox) to the membrane are essential for activation of the NADPH oxidase and generation of O-2. beta-PKC depletion had no effect on the level of p47(phox) in dHL60 cells but did significantly decrease ligand-induced phosphorylation of this protein. Furthermore, translocation of p47(phox) to the membrane in response to phorbol myristate acetate or fMet-Leu-Phe was reduced in beta-PKC-depleted cells. These results indicate that beta-PKC is essential for signaling for O-2 generation but not cell adherence or azurophil degranulation. Depletion of beta-PKC inhibited ligand-induced phosphorylation of p47(phox), translocation of p47(phox) to the membrane, and activation of O-2 generation.     

Occult B cell malignancies can be detected by three-color flow cytometry in patients with cytopenias

Patients with unexplained cytopenias often present a diagnostic dilemma with minimal morphologic or cytogenetic changes to identify the underlying disease process. We have used multidimensional flow cytometry in a study of patients with cytopenias and found that this technology established, changed, or refined the diagnosis in 17/121 patients. Using the flow cytometric technique of CD45 and right angle light scatter (SSC) gating with two additional markers in a three-color analysis, eight of 121 patients were found to have hairy cell leukemia (HCL), in the absence of definitive morphologic findings of HCL. Two additional patients were found to have non-Hodgkin's lymphoma (NHL). Myeloid abnormalities, myelodysplasia (MDS) or acute leukemia was detected in seven of 56 patients with unexplained pancytopenia. Six of 65 patients identified with cytopenias resulting from lymphoid neoplasms had been referred for bone marrow transplantation (BMT) with a presumptive diagnosis of MDS, with subsequent deferral of BMT upon correct diagnosis. The screening technique is incorporated into an extensive immunophenotyping scheme to identify hematopoietic abnormalities using multidimensional flow cytometry (MDF). HCL cells (detected as low as 1.3%) reside in the same position as normal monocytes in the CD45 and SSC plots but could be distinguished from monocytes based on the expression of HLA-DR without CD11b, and expression of CD19. Further phenotyping of the abnormal population confirmed immunoglobulin light chain restriction, CD11c, and CD25 expression. Non-Hodgkin's lymphoma was detected as aberrant mature lymphocytes expressing B lymphoid markers, CD5 and light chain restriction. Myeloid abnormalities were identified in the myeloblast or maturing myeloid cell fractions. The flow cytometric scheme described can be used in primary diagnosis. The technique is definitive, sensitive, and stresses the importance of distinguishing lymphoid from myeloid etiology of cytopenias.     

Pharmacological characterization of a simple behavioral response mediated selectively by central adenosine A1 receptors, using in vivo and in vitro techniques

Mouse embryonic carcinoma P19 cell aggregates treated with retinoic acid (RA) sequentially differentiate into neurons and astrocytes, whereas attached cells develop a mesodermal phenotype. The expression of calcitonin (CT) and PTH/PTH-related protein (PTHrP) receptors was investigated in embryonic cells, and during neural and mesodermal differentiation. In embryonic P19 cells, specific binding of [125I]salmon (s) CT(1-32) ([125I]sCT(1-32)) was 56 fmol/mg protein, and of [125I]chicken (ch) [Tyr36]PTHrP(1-36) amide ([125I]chPTHrP(1-36)) < 0.5 fmol/mg protein. Correspondingly, cAMP was maximally stimulated 47-fold by sCT(1-32) (EC50 0.05 nM) and 3-fold by chPTHrP(1-36) (EC50 1.3 nM). Receptor autoradiography revealed specific binding of [125I]sCT(1-32) to the undifferentiated P19 cells, but not to RA induced neurons and astrocytes. At the same time, [125I]sCT(1-32) binding and cAMP accumulation by sCT were gradually decreased. But, specific binding of [125I]chPTHrP(1-36) was raised at least 6-fold compared with embryonic cells to 3 fmol/mg protein, in parallel with a 10-fold higher maximal cAMP accumulation. A similar, but delayed suppression of CT and stimulation of PTH/PTHrP receptor expression was observed during mesodermal cell differentiation. The results indicate that CT receptors are associated with undifferentiated P19 cells, whereas PTH/PTHrP receptors are expressed in RA induced neural and mesodermal cells.     

Comparison of two-dimensional MR digital subtraction angiography of the lower extremity with x-ray angiography

PURPOSE: To perform a preliminary evaluation of the diagnostic accuracy of contrast-enhanced, two-dimensional (2D) magnetic resonance (MR) digital subtraction angiography (DSA) of the lower extremity by comparison with x-ray angiography (XRA). MATERIALS AND METHODS: Forty lower extremities in 22 patients were imaged at multiple levels with both XRA and 2D MR DSA. Images were retrospectively analyzed by three radiologists in a randomized blinded manner. Seventeen vascular segments were graded as an insignificant lesion, a significant lesion, or as an occlusion. With the use of segments well depicted with XRA as the gold standard, the sensitivity, specificity, and accuracy of 2D MR DSA, as compared with XRA, were evaluated. The McNemar-Stuart-Maxwell test was performed to determine the significance of any differences found. RESULTS: Three hundred eighty-three arterial segments were evaluated with both techniques. Three hundred one segments were well depicted with XRA. There was no significant difference between 2D MR DSA and XRA for assessing the degree of occlusive disease in these 301 segments (.25 < P < .5). The sensitivity, specificity, and diagnostic accuracy of 2D MR DSA were found to be 90%, 98%, and 93%, respectively. CONCLUSION: Two-dimensional MR DSA is an accurate method for assessing arterial lesions in the lower extremity.     

Induced luteolysis in the primate: rapid loss of luteinizing hormone receptors

The molecular mechanisms involved in luteolysis are still unclear in the primate. This study aimed to investigate the effect of induced luteolysis on the ovarian luteinizing hormone (LH) receptor and the steroidogenic enzyme, 3beta-hydroxysteroid dehydrogenase (3beta-HSD) in the marmoset monkey. Luteolysis was induced in the mid-luteal phase either directly by systemic prostaglandin F2alpha (PGF2alpha), or indirectly by LH withdrawal using systemic gonadotrophin releasing hormone antagonist (GnRHant) treatment. The LH receptor was studied by isotopic mRNA in-situ hybridization and in-situ ligand binding and 3beta-HSD expression was studied using isotopic mRNA in-situ hybridization and immunohistochemistry. Induced luteolysis was associated with a reduction in the expression of LH receptor (P < 0.0001) and 3beta-HSD mRNA, closely followed by a reduction in the LH receptor (P < 0.05) and 3beta-HSD protein concentrations within 24 h. There were no differences in the findings whether luteolysis was induced with PGF2alpha or GnRHant. This study shows that disparate mechanisms to induce luteolysis in the primate result in an identical rapid loss of the LH receptor and 3beta-HSD. In conclusion, induced luteolysis leads to rapid loss of the steroidogenic pathway in luteal cells.