Search PubMed⌕ Search

Biomedical subjects

A Bose

Publications and source records attributed to A Bose.

At least 55 records · Page 3Linked to original sources

Computer simulations of chondrocytic clone behaviour in rabbit growth plates.

The growth behaviour of chondrocytic clones in the cell columns of the proximal tibial growth plates of young rabbits was modelled in computer simulations. Simulations were performed, modelling either clones in large groups of columns or clones in one single column. The former were based on morphological data and measurements of cell columns from an earlier study while the latter utilised previous findings of cellular kinetics in rabbit growth plates. Simulation results that resembled most closely the actual observations on rabbit growth plates were those in which a distribution of values was assumed both for clone length (ranging from 1000 to 2000 microns) and for the lengths of the discontinuities between clones. When the assumption was made in the models that the disappearing (metaphyseal) end of an 'old' clone moved more rapidly than the developing (epiphyseal) end of a 'new' clone, replacing the former, the length of the discontinuity between these two clones increased with time. This assumption, which could be modelled in the simulations of clones in a single column based on cell growth behaviour, was found to provide an explanation for an earlier finding that there are more short columns at the epiphyseal side than at the metaphyseal side of a growth plate.

Animals↗

SPECT in patients with epilepsia partialis continua.

We report 2 patients with epilepsia partialis continua (EPC) in whom ictal single photon emission computed tomography (SPECT) showed focal increased signal while EEG failed to show epileptic changes. SPECT may clarify confusing situations when EPC is suspected.

Aged↗

Structure of a modified cytosine: an antiviral nucleoside analog, homo-Ara-C.

Homo-Ara-C [5'-(hydroxymethyl)-5'-deoxy-1-beta-D-arabinofuranosyl-3H- cytosine], C10H16N3O5, Mr = 258.25, P2,2,2, a = 8.261 (2), b = 19.644 (4), c = 6.993 (6) A, V = 1134.8 A3, Z = 4, Dx = 1.511 g cm-3, lambda (Cu Ka) = 1.5418 A, mu = 10.5 cm-1, F(000) = 548, T = 288 K, final R = 0.053 for 1189 observed reflections. Conformational features of the nucleoside include a glycosidic bond conformation in the anti range, a ribose moiety in the 2E [C(2')-endo] form like 5'-N3-Ara-C, 5-NO2-Ara-U and Ara-C and a C(5')-C(6') bond that is gauche to C(4')-O(4') but trans to C(4')-C(3').

Crystallography↗

Effects of pre-weaning undernutrition on 21 day-old male rat skull form as described by the finite element method.

Conventional Roentgenographic Cephalometric Methods (RCM) have certain conceptual and geometric constraints that ensure that their descriptions of cephalic growth and comparisons of cephalic form are reference-frame-dependent; and it is impossible to determine which, if any, RCM reference frame provides a biologically more correct description or comparison. The use of the concepts of continuum mechanics and of the numerical techniques of the Finite Element Method (FEM) overcomes these constraints and provides reference-frame-independent (invariant) growth descriptions and form comparisons. In the FEM, the structure of the head is subdivided (discretized) into a number of smaller, finite, elements. The FEM then describes the growth behavior, or compares the form, of the entire continuum of points enclosed with each element independently; in RCM only the behaviors, or comparisons, of the landmark points are described. The FEM is described and its use illustrated by a comparison of the cephalic forms of 4 groups of weanling (21 d old) rats. The 1st (control) group is derived from normally nourished dams, while the other 3 groups are derived from dams who were malnourished throughout the weaning period in 3 group specific manners. The FEM permitted reference-frame-independent comparisons of the 4 different, and group specific, head forms. These differences were reflected in the forms of each of the finite elements. The differences in element forms between the 4 groups were shown to be related primarily to nutritionally produced alterations of either neurocranial or splanchocranial viscera. These differences were expressed in the alterations of the forms of the continua enclosed within the boundaries of the several finite elements, and secondarily in the form of the cranial skeleton.

Animals↗

Differentiation of posterior pararenal space infection from psoas abscess by gallium imaging.

Three of four patients whose cases fit the clinical description of psoas abscess proved on gallium imaging to have infection in the posterior pararenal space sparing the psoas muscle. This space provides a route for spread of infection connecting the spine, the anterior abdominal wall, the scrotum, the anterior thigh, and the gluteal region as demonstrated by the cases presented. Clinical differentiation between posterior pararenal space infection and psoas abscesses is difficult and CT studies may not demonstrate the process when the psoas space is not involved.

Abdomen↗

Azarcón por empacho--another cause of lead toxicity.

A new source of toxic lead ingestion has been identified roentgenologically in Mexican-American children and adults. Azarcón is an orange powder that contains 86% to 95% lead tetroxide (Pb3O4). At least three children have been treated with this substance by folk healers for relief of abdominal symptoms. Other Hispanic medical folklores may include this toxic "remedy."

Child↗

A monoclonal antiidiotypic antibody to MOPC 315 IgA inhibits the growth of MOPC 315 myeloma cells in vitro.

Spleen cells from BALB/c mice immunized with MOPC 315 IgA were fused with P3X63/Ag8 myeloma cells. Hybrid clones were screened for antibody production by a plate-binding radioimmunoassay in which MOPC 315 IgA was reacted with culture supernatants and 125I-protein A. One antibody-producing hybridoma clone (D10) was selected and injected i.p. into BALB/c mice. Ascitic fluid of tum or-bearing animals reacted specifically with MOPC 315 IgA and the reaction was inhibited by DNP- aminocaproic acid, indicating that the monoclonal antibody was directed against the hapten-binding site of MOPC 315 IgA. The monoclonal antiidiotypic antibody was of the complement (C)-binding IgG2a subclass and inhibited IgA production and growth of MOPC 315 cells in vitro in the presence of guinea pig C, as assessed by inhibition of formation of plaques and colonies by MOPC 315 cells in agar.

Animals↗

Induction of cytotoxic factors by immunization of mice with Freund's adjuvant components.

Antiidiotypic antibody (AIA) was raised in mice by immunization with MOPC 315 immunoglobulin A emulsified in Freund's adjuvant (FA). The antibody content of mouse serum was assessed by (a) its ability to inhibit rosetting of 2,4,6-trinitro-phenyl-sheep red blood cells around MOPC 315 myeloma cells, and (b) by a solid phase antigen-binding plate assay based on reactivity with 125I-Protein A and inhibition in the presence of dinitrophenyl aminocaproic acid. FA was necessary for the production of AIA to MOPC 315 immunoglobulin A. Some of the AIA-containing mouse sera were cytotoxic for MOPC 315 cells in the presence of guinea pig complement. However, cytotoxicity was not correlated with amount of AIA, as assessed by inhibition of rosette formation, nor was it specific for myeloma cells bearing the MOPC 315 idiotype. Furthermore, cytotoxicity could also be generated by immunization of mice with complete Freund's adjuvant, incomplete Freund's adjuvant, or the muramyl dipeptide portion of mycobacteria, all in the absence of MOPC 315 immunoglobulin A. Therefore, the complement-dependent cytotoxic antibodies in the AIA-containing antisera, which belonged to the immunoglobulin G and M classes, were likely directed against some component of FA. Myeloma cells which were not killed by anti-FA antiserum, as assessed by dye exclusion, were inhibited in their ability to secrete immunoglobulin and to form clones in agar.

Acetylmuramyl-Alanyl-Isoglutamine↗