Monoclonal antibody production to human and bovine 2′:3′-cyclic nucleotide 3′-phosphodiesterase (CNPase): high-specificity recognition in whole brain acetone powders and conservation of sequence between CNP1 and CNP2

Monoclonal antibodies against human and bovine 2′:3′-cyclic nucleotide 3′-phosphodiesterase (CNPase) were generated by fusing FOX-NY myeloma cells with spleen cells from RBF/Dn mice previously immunized with the purified brain antigens. The enzyme isolated from bovine brain was quite basic, with an isoelectric point of 9.71 and both the bovine and human enzymes consisted of a closely spaced doublet at approximately 44 and 46 kDa on SDS-PAGE. Six monoclonals were identified as strongly recognizing the enzyme on both ELISA plates and on immunoblots of whole brain protein. Four monoclonals very weakly cross-reacted with guinea pig myelin basic protein. In contrast with two previous reports, some of our monoclonal antibodies did immunostain 2 or 3 protein bands in peripheral nerve, two bands closely corresponding to those immunostained in central nervous system (CNS) myelin, the Wolfgram protein fraction and in acetone powders of whole brain. Each of the 6 monoclonals reacting strongly on immunoblots recognized the enzyme in from 2 to 5 of the species examined (human, bovine, rat, mouse and rabbit). In addition, all 6 monoclonals that immunostained the enzyme in whole brain, myelin and Wolfgram protein immunoblots recognized both CNP1 (44 kDa) and CNP2 (46 kDa). The two closely spaced protein bands observed on SDS-PAGE and previously stained on immunoblots of CNS CNPase using polyvalent rabbit anti-bovine CNPase antisera, and now different monoclonal antibodies, appear to be immunologically related and to contain highly conserved sequences.     

Monoclonal antibodies against the chronic lymphatic leukemia antigen cCLLa: characterization and reactivity

Monoclonal antibodies (MoAbs) were developed against the cCLLa, a 69-kilodalton leukemia-associated antigen expressed on malignant cells of B-type chronic lymphatic leukemia (B-CLL) and its variants: prolymphocytic (PLL) and hairy cell leukemias (HCL). Two hybridomas yielded approximately 2 and approximately 7.5 mg/mL of IgG2a kappa and IgM kappa, respectively. Monoclonal surface immunoglobulin-bearing cells of all B-CLL patients studied (n = 30) reacted with the MoAbs (r greater than .99) regardless of stage or lymphocyte count. This suggests that the malignant clone in CLL can be identified and its size monitored by using our MoAbs. In contrast, normal B lymphocytes, a large panel of normal, reactive and neoplastic cells, and malignant cell lines failed to react with either MoAb as judged by indirect immunofluorescence and by flow cytometry. Only two patients (one with non-Hodgkin's lymphoma, the other with acute myeloblastic leukemia) exhibited a small cell subset reactive with the MoAbs. cCLLa specificity was suggested by selective target cell reactivity and competitive inhibition-absorption and confirmed by immunoprecipitation. MoAbs IgG2a kappa and IgM kappa appeared to share antigenic determinants and were moderate and avid complement binders inducing 100% and 40% target cell lysis, respectively. cCLLa density on malignant CLL and HCL cells was estimated by equilibrium binding studies using the IgG2a kappa MoAb at 1.7 and 9 X 10(6)/cell, respectively. The restricted expression of the cCLLa and the specificity and cytolytic activity of the anti-cCLLa MoAbs support these antibodies as probes for the classification of lymphoproliferative diseases and for the specific diagnosis and treatment of B-CLL and its variants.     

Dentine sealing provided by smear layer/smear plugs vs. adhesive resins/resin tags

The aim of this study was to evaluate the ability of five experimental resins, which ranged from hydrophobic to hydrophilic blends, to seal acid-etched dentine saturated with water or ethanol. The experimental resins (R1, R2, R3, R4, and R5) were evaluated as neat bonding agents (100% resin) or as solutions solvated with absolute ethanol (70% resin/30% ethanol). Fluid conductance was measured at 20 cm H(2)O hydrostatic pressure after sound dentine surfaces were: (i) covered with a smear layer; (ii) acid-etched; or (iii) bonded with neat or solvated resins, which were applied to acid-etched dentine saturated with water or ethanol. In general, the fluid conductance of resin-bonded dentine was significantly higher than that of smear layer-covered dentine. However, when the most hydrophobic neat resins (R1 and R2) were applied to acid-etched dentine saturated with ethanol, the fluid conductance was as low as that produced by smear layers. The fluid conductance of resin-bonded dentine saturated with ethanol was significantly lower than for resin bonded to water-saturated dentine, except for resin R4. Application of more hydrophobic resins may provide better sealing of acid-etched dentine if the substrate is saturated with ethanol instead of with water.     

Endoscopic release of the carpal tunnel: A randomized prospective multicenter study

A 10-center randomized prospective multicenter study of endoscopic release of the carpal tunnel was carried out. Surgery was performed with a new device for transecting the transverse carpal ligament while control hands were treated with conventional open surgery. There were 122 patients in the study; 25 had carpal tunnel surgery on both hands and 97 had surgery on one hand. Of the surgical procedures, 65 were in the control group and 82 were in the device group. The endoscopic device was coupled to a fiberoptic light and a video camera. A trigger-activated blade was used to incise the transverse carpal ligament. After surgery, the best predictors of return to work and to activities of daily living were strength and tenderness variables. For patients in the device group with one affected hand, the median time for return to work was 21 1/2 days less than that for the control group. Two patients treated with the endoscopic device required reoperation by open surgical decompression; only one of these had incomplete release with the device. Two patients in the device group experienced transient ulnar neurapraxia.     

Drug-induced liver injury. In vitro demonstration of hypersensitivity to both phenytoin and phenobarbital

Fever, lymphadenopathy, exfoliative dermatitis, and evidence of drug-induced liver injury developed in a 16-year-old girl three weeks after beginning therapy with phenytoin and phenobarbital. This clinical syndrome can be caused by either of these structurally related drugs but has been more frequently attributed to phenytoin. In vitro studies disclosed marked reactivity of this patient's lymphocytes to concentrations of both drugs, which encompassed their measured serum levels. The demonstration of dual reactivity raises concerns about continuing administration of phenobarbital during an apparent phenytoin-induced reaction. Whether this potential risk is greater than the risk of stopping all anticonvulsant medications in a patient with a seizure disorder is not known and remains to be established.     

Permeability of demineralized dentin to HEMA.

OBJECTIVES: The objectives of this study were to develop a macromodel of the demineralized layer of dentin that is formed after acid-etching, and to determine if the amount of HEMA uptake was responsive to air drying. The hypothesis that was tested was that HEMA uptake by demineralized dentin depends upon the degree of expansion of the collagen fibril network. METHODS: Dentin cubes (2 x 2 x 2 mm) were prepared in coronal dentin from extracted unerupted human third molars. They were incubated in 100% HEMA for up to 1000 min and then removed and blotted free of excess adherent HEMA. The HEMA taken up by each cube was extracted in 2 ml of water for 1 hr with shaking. This was repeated and the extracts combined. HEMA was quantitated spectrophometrically. The dentin cubes were then demineralized in 0.5 M EDTA for 10 days and the HEMA uptake remeasured at 1, 10, 100 and 1000 min. Then the cubes were air-dried and the HEMA uptake remeasured. After re-expanding the specimens in water, the cubes were stiffened in ascending concentrations of acetone of 100%, then allowed to air dry again in a more expanded state, and HEMA uptake was remeasured. Finally, after rehydration, the dentin cubes were "acid-etched" for 1 or 10 min with 37 wt% phosphoric acid and HEMA uptake remeasured. RESULTS: Before demineralization, the dentin took up little HEMA (ca. 4.8 x 10(-7) moles min-3) compared to after demineralization when the uptake for 10, 100 and 1000 min was 27.4, 43.8 and 51.4 x 10(-3) moles mm-3, respectively. Acid etching for 1 or 10 min had no effect on HEMA uptake. Air drying produced a 72% volumetric shrinkage but a 97% reduction in uptake. When the demineralized matrix was stiffened in acetone prior to air-drying, the volumetric shrinkage was only 27% and the HEMA uptake only fell 16% compared to the wet, fully expanded condition. SIGNIFICANCE: The results support the hypothesis that the uptake of HEMA by demineralized dentin depends on the degree of expansion of the dentin matrix.     

Unstable fracture dislocations of the proximal interphalangeal joint. Treatment with the force couple splint

The force couple splint maintains concentric joint reduction while allowing early active range of motion exercises. Sixteen cases were treated with a force couple created across the proximal interphalangeal (PIP) joint, levering the dislocated base of the middle phalanx palmarly, while simultaneously lifting the distal end of the proximal phalanx dorsally to restore joint reduction. The splint is constructed from three Kirschner wires and is activated by a single rubber band. The effect of this force couple is present through a complete range of joint motion, thereby allowing active flexion and extension of the joint during bone and soft tissue healing. The force couple splint is capable of producing good to excellent results in patients with unstable acute fracture dislocations of the PIP joint.