An interactive, microcomputer-based karyotype analysis system for phylogenetic cytotaxonomy

A versatile and practical semi-automatic computerized system of karyotype analysis has been developed for phylogenetic cytotaxonomy for under $4,000. The modular software system is designed for use solely with a small 8-bit microcomputer and requires virtually no custom made hardware. The system interacts with the operator and greatly augments the speed and accuracy of cytotaxonomic investigations.     

Serum alpha 2-macroglobulin levels in diabetes.

Serum alpha 2-macroglobulin levels have been determined in diabetic patients by quantitative radial immunodiffusion and compared with those observed in age- and sex-matched controls. In addition, the results in diabetics have been analysed with respect to such variables as the age and sex of the patient, the duration of disease, treatment, control, and the occurrence of retinopathy or nephropathy. The alpha 2-macroglobulin levels in diabetic patients were found to be significantly higher than in age- and sex-matched controls, thus confirming previous observations. However, these differences were most apparent in the more extreme age groups. Multiple regression analysis also revealed that the only variables contributing significantly to the regression apart from age and sex were control and retinopathy.     

IL-15 enhances the function and inhibits CD95/Fas-induced apoptosis of human CD4+ and CD8+ effector-memory T cells

Although the effect of IL-15 has been described on murine cells in vitro and in vivo, its effect on human memory CD8(+) T cells is not well characterized. We show here that IL-15 preferentially enhances the activation and effector function of human effector-memory CD45RA(-)CD62L(-) and CD45RA(+)CD62L(-) CD4(+) and CD8(+) T cells in both healthy and HIV-infected individuals. We find that IL-15 increases 2- to 5-fold both the activation and secretion of the effector cytokines IFN-gamma and tumor necrosis factor (TNF)-alpha by anti-CD3-stimulated purified CD4(+) and CD8(+) T cells and peripheral blood mononuclear cells from healthy and HIV-infected individuals. Furthermore, IL-15 potently inhibits CD95/Fas-induced apoptosis of the effector-memory CD4(+) and CD8(+) T cells from HIV-infected individuals. These findings suggest that in addition to being a growth and survival factor for memory CD8(+) T cells, IL-15 is also a potent activator of human effector-memory CD8(+) T cells both in healthy and in HIV-infected individuals.     

Monocyte chemotactic protein-3 (MCP3) interacts with multiple leukocyte receptors: binding and signaling of MCP3 through shared as well as unique receptors on monocytes and neutrophils

The diversity of monocyte chemotactic protein (MCP)3 target cell types, as well as the capacity of MCP3 to desensitize leukocyte responses to other CC chemokines, suggested that MCP3 may interact with multiple CC chemokine receptors. The purpose of this study is to establish how MCP3 binds and activates monocytes and neutrophils. We show that human monocytes exhibit high-affinity binding for ¹²⁵I-MCP3 with an estimated Kd of 1–3 nM and about 10000 binding sites/cell. The binding of ¹²⁵I-MCP3 to monocytes was progressively less well competed by CC chemokines macrophage inflammatory protein (MIP)lα (Kd = 5–10 nM), RANTES (Kd = 5–10 nM), MCP1 (monocyte chemoattractant and activating factor, or MCAF) (Kd = 60 nM) and MIP1β (Kd > 100 nM). On the other hand, unlabeled MCP3 displaced the binding of radiolabeled MIP1α, RANTES, MCP1 and MIP1β as effectively as the isologous CC chemokines. In agreement with the binding data, pretreatment of monocytes with MCP3 completely desensitized the calcium flux in response to MIP1α and RANTES. However, MIP1α and RANTES failed to desensitize the response of monocytes to MCP3. MCP3 and MCP1 partially desensitized each other's effects on monocytes. These binding and cross-desensitization results suggest that MCP3 binds and signals through other binding sites in addition to those shared with MIP1α, RANTES and MCP1. The unidirectional competition for MIP1β binding and signaling by MCP3 suggests the existence of an as-yet unidentified site for MCP3 shared with MIP1β. The existence of another unique binding site(s) for MCP3 was further shown by the failure of any of the other CC chemokines to compete effectively for MCP3 binding on neutrophils. MCP3 in our study was also the only human CC chemokine that consistently chemoattracted neutrophils. These results suggest that MCP3 is a ligand that can bind and activate a broad range of target cells through receptors shared by other CC chemokines as well as its own receptor.     

Acute back pain: A control-group comparison of behavioral vs traditional management methods

Back-pain patients with onset in the preceding 1–10 days and comparable on a back examination were randomly assigned to traditional management (A regimen) and behavioral treatment methods (B regimen). Patients were compared at 6 weeks and 9–12 months on a set of Sick/Well scores derived from patient reported vocational status (V), health-care utilization (HCU), claimed impairment (CI), and pain drawings (D) and on two measures of activity level. No differences were found at 6 weeks, but at 9–12 months, A-group S's were more sick. No A/B differences were found on activity-level measures. Group A S's showed significant increases in claimed impairment from preonset to follow-up, whereas Group B S's had returned at follow-up to preonset levelsA special acknowledgment is made to Darnel Rock, M.S., now of the Department of Psychology, Vanderbilt University, for his major contributions to the organization and analysis of the data of this study.     

Transformation of B and non-B cell lines with the 2,4,6,-trinitrophenyl (TNP)-specific immunoglobulin genes

The rearranged mu and kappa genes from the 2,4,6-trinitrophenyl (TNP)-specific hybridoma Sp6 have been introduced into B cells from three different stages of differentiation as well as 5 non-B cell lines to determine the levels and modes of immunoglobulin (Ig) gene expression. In pre-B cells transformed with the mu and kappa genes, low levels of Sp6-specific mu RNA were produced and approximately 210-fold less mu and 800-fold less kappa proteins were produced than in the hybridoma Sp6. The Ig proteins were present intracellularly, but were not detected on the cell membrane. In mature surface sIg+ B cell transformants, higher levels of mu Sp6 and kappa Sp6 proteins and RNA were produced than in the pre-B cell transformants (12 X mu, 70 X kappa). These transformants displayed the mu Sp6 and kappa Sp6 proteins on the cell membrane and also secreted the transfected Ig product. Plasma cell transformants produced the highest amounts of mu Sp6 and kappa Sp6 proteins. These transformants secreted pentameric IgM but did not display detectable amounts of these proteins on the cell membrane. T cell and one fibroblast transformant produced Ig as normal sized mu Sp6 and kappa Sp6 proteins. All other mu Sp6 and kappa Sp6 non-B cell transformants (melanoma, teratoma and macrophage) failed to produce enough Ig to determine whether the Ig proteins were of the correct molecular weights. The T cell and fibroblast transformants that produced Ig proteins did not secrete or display detectable Ig on the cell membrane. The expression of Ig did not inhibit the expression of the T cell antigen Thy-1 in the T cell transformants.     

Partial trisomy 6p and partial monosomy 9p from a de novo translocation 46, XY, -9, + DER(9)T(6:9)(p211:p24)

This report describes an adult male with a partial trisomy 6p(p211-pter) and a partial monosomy 9p(9p24-pter) resulting from a de novo unbalanced translocation. This patient does not show the classical featured of the 9p partial monosomy syndrome, thus disputing the claim of Hoo et al. (1982) that 9p24 is the critical segment for the monosomy syndrome. Partial trisomy for 6p has only been previously reported in children. In addition to the chromosomal anomalies, the patient has autosomal recessive spinal muscular atrophy with a different age of onset than two affected sibs. Finally, he shows unusual audiologic and ophthalmologic signs nor previously reported as part of the 9p monosomy or 6p trisomy syndromes.     

Activation dependence and kinetics of force and stiffness inhibition by aluminiofluoride,a slowly dissociating analogue of inorganic phosphate,in chemically skinned fibres from rabbit psoas muscle

Summary To examine the mechanism by which aluminiofluoride, a tightly binding analogue of inorganic phosphate, inhibits force in single, chemically skinned fibres from rabbit psoas muscle, we measured the Ca²⁺-dependence of the kinetics of inhibitor dissociation and the kinetics of actomyosin interactions when aluminiofluoride was bound to the crossbridges. The relation between stiffness and the speed of stretch during small amplitude ramp stretches (< 5 nm per h.s.) was used to characterize the kinetic properties of crossbridges attached to actin; sarcomere length was assessed with HeNe laser diffraction. During maximum Ca²⁺-activation at physiological ionic strength (pCa 4.0, 0.2 m /2), stiffness exhibited a steep dependence on the rate of stretch; aluminiofluoride inhibition at pCa 4.0 (0.2 m /2) resulted in an overall decrease in stiffness, with stiffness at high rates of stretch (10³–10⁴ nm per h.s. per s) being disproportionately reduced. Thus the slope of the stiffness-speed relation was reduced during aluminiofluoride inhibition of activated fibres. Relaxation of inhibited fibres (pCa 9.2, 0.2 m /2) resulted in aluminiofluoride being trapped and was accompanied by a further decrease in stiffness at all rates of stretch which was comparable to that found in control relaxed fibres. In relaxed, low ionic strength conditions (pCa 9.2, 0.02 m /2) which promote weak crossbridge binding, stiffness at all rates of stretch was significantly inhibited by aluminiofluoride trapped in the fibre. To determine the Ca²⁺-dependence of inhibitor dissociation, force was regulated independent of Ca²⁺ using an activating tropinin C (aTnC). Results obtained with aTnC-activated fibres confirmed that there is no absolute requirement for Ca²⁺ for recovery from force inhibition by inorganic phosphate analogues in skinned fibres; the only requirement is thin filament activation which enables active crossbridge cycling. These results indicate that aluminiofluoride preferentially inhibits rapid equilibrium or weak crossbridge attachment to actin, that aluminiofluoride-bound crossbridges attach tightly to the activated thin filament, and that, at maximal (or near-maximal) activation, crossbridge attachment to actin prior to inorganic phosphate analogue dissociation is the primary event regulated by Ca²⁺.