Choriocarcinoma metastatic to the lung. A cytologic study with identification of human choriogonadotropin with an immunoperoxidase technique

A case of choriocarcinoma metastatic to the lung following a previous hydatidiform mole is presented. It was possible to make definitive identification of trophoblastic elements on a needle aspiration biopsy using an immunoperoxidase staining technique, thus avoiding diagnostic thoracotomy prior to therapeutic intervention. A method of immunoperoxidase staining of previously fixed and Papanicolaou-stained needle aspiration biopsy specimens is also described, and other uses of the immunoperoxidase technique on needle biopsy specimens are discussed.     

Chick embryo fibroblasts produce two forms of hyaluronidase

Cultured chick embryo fibroblasts derived from skin and skeletal muscle exhibit hyaluronidase activity both associated with the cell layer and secreted into the medium. Although both forms of the enzyme have a number of similar characteristics (R.W. Orkin and B.P. Toole, 1980, J. Biol. CHem. 255), they differ in thermal stability at neutral pH and in behavior on ion-exchange chromatography. Both forms of the enzyme are equally stable at acidic pH for long intervals, but the cell-associated hyaluronidase is significantly less stable than the secreted froms at neutral pH and at temperatures more than or equal to 30 degrees C. Neither the presence of proteases nor inhibitors of hyaluronidase appear to be involved in the cell-asspcoated enzyme. Chromatography of the two forms of hyaluronidase on carboxymethyl cellulose reveals that most (60-90 percent) of the secreted form of the enzyme elutes at a lower ionic strength than the cell- associated enzyme. Treatment of the secreted form of hyaluronidase with neuraminidase shifts its elution profile on carboxymethyl cellulose toward that of the cell-associated form, and also decreases its thermal stability at neutral pH. In contrast, treatment of the secreted form of hyaluronidase with alkaline phosphatase has no detectable effect. These data suggest that the secreted hyaluronidase differs from the cellular form in possessing additional sialic acid residues which endow the former with increased stability in the extracellular milieu.     

Intense photon emission induced by fracture of γ–irradiated Dy‐, Tm‐, Sm‐ and Mn‐doped CaSO4 single crystals

When an γ‐irradiated Dy‐, Tm‐, Sm‐ or Mn‐doped CaSO₄ crystal is impulsively deformed, two peaks appear in the ML intensity versus time curve, whereby the first ML peak is found in the deformation region and the second in the post‐deformation region of the crystals. In this study, intensities I_m1 and I_m2 corresponding to first and second ML peaks, respectively, increased linearly with an impact velocity v₀ of the piston used to deform the crystals, and times t_m1 and t_m2 corresponding to the first and second ML peaks, respectively, decreased with impact velocity. Total ML intensity initially increased with impact velocity and then reached a saturation value for higher values of impact velocity. ML intensity increased with increasing γ‐doses and size of crystals. Results showed that the electric field produced as a result of charging of newly‐created surfaces caused tunneling of electrons to the valence band of the hole‐trapping centres. The free holes generated moved in the valence band and their subsequent recombination with electron trapping centres released energy, thereby resulting in excitation of luminescent centres. Copyright © 2012 John Wiley & Sons, Ltd.     

Increased anxiety-like behavior and enhanced synaptic efficacy in the amygdala of GluR5 knockout mice

GABAergic transmission in the amygdala modulates the expression of anxiety. Understanding the interplay between GABAergic transmission and excitatory circuits in the amygdala is, therefore, critical for understanding the neurobiological basis of anxiety. Here, we used a multi-disciplinary approach to demonstrate that GluR5-containing kainate receptors regulate local inhibitory circuits, modulate the excitatory transmission from the basolateral amygdala to the central amygdala, and control behavioral anxiety. Genetic deletion of GluR5 or local injection of a GluR5 antagonist into the basolateral amygdala increases anxiety-like behavior. Activation of GluR5 selectively depolarized inhibitory neurons, thereby increasing GABA release and contributing to tonic GABA current in the basolateral amygdala. The enhanced GABAergic transmission leads to reduced excitatory inputs in the central amygdala. Our results suggest that GluR5 is a key regulator of inhibitory circuits in the amygdala and highlight the potential use of GluR5-specific drugs in the treatment of pathological anxiety.     

Residue 3 of β2-microglobulin affects binding of class I MHC molecules by the W6/32 antibody

 Previous studies of class I MHC molecules have shown that the owl monkey (Aotus) possesses at least two variants of the β₂-microglobulin (β₂m) protein. These two variants have different isoelectric points, and exhibit differential reactivity with the monoclonal antibody W6/32. We report cDNA sequences of the B2m gene, from W6/32-positive and W6/32-negative Aotus cell lines. The two β₂m variants we identified exhibit a single amino acid difference at position three. An arginine residue at position 3 was correlated with W6/32 reactivity, whereas histidine was associated with non-reactivity. W6/32 reactivity was conferred to a W6/32-negative Aotus cell line when it was transfected with the B2m from the W6/32-positive cell line. Residue 3 of β₂m is located at the surface of the class I molecule. It is also close to position 121 of the MHC class I heavy chain, which has previously been shown to influence W6/32 antibody binding. We conclude that W6/32 binds a compact epitope on the class I molecule that includes both residue 3 of β₂m and residue 121 of the heavy chain. We examined the distribution of the two β₂m motifs in a sample Aotus population using an allele-specific polymerase chain reaction assay. The pattern of β₂m segregation we observed matches that which was defined previously by serology. Additionally, we identified laboratory-born hybrid animals who possess both variants of β₂m. Received: 1 April 1998 / Received: 3 July 1998     

The design and synthesis of purine inhibitors of CDK2. III

Cyclin-dependent kinases (CDKs) belong to a class of enzymes that control the ability of a cell to enter into and proceed through the cell division cycle. Using purine as a scaffold, we have synthesized a number of nanomolar inhibitors of CDK-2/cyclin E. In this report, the synthesis of a series of piperidine-substituted purine analogs will be presented, as well as some of their in vitro and in vivo biological effects.     

SM22beta encodes a lineage-restricted cytoskeletal protein with a unique developmentally regulated pattern of expression

Cytoskeletal proteins play important roles in regulating cellular morphology, cytokinesis and intracellular signaling. In this report, we describe a developmentally regulated gene encoding a novel cell lineage-restricted cytoskeletal protein, designated SM22beta. SM22beta shares high-grade sequence identity with the smooth muscle cell (SMC)-specific protein, SM22alpha, the neuron-specific protein, NP25, and the Drosophila melanogaster flight muscle-specific protein, mp20. The mouse SM22beta cDNA encodes a 199-amino acid polypeptide that contains a single conserved calponin-like repeat domain. During mouse embryonic development, the SM22beta gene is expressed in a temporally and spatially regulated pattern in the tunica media of arteries and veins, endocardium and compact layer of the myocardium, bronchial epithelium and mesenchyme of the lung, gastrointestinal epithelium and cartilaginous primordia. During postnatal development, SM22beta is co-expressed with SM22alpha in arterial and venous SMCs. In addition, SM22beta is expressed at high levels in the bronchial epithelium and lung mesenchyme, gastrointestinal epithelial cells and in the cartilagenous and periosteal layer of bones. Three-dimensional deconvolution microscopic analyses of A7r5 SMCs revealed that SM22beta co-localizes with SM22alpha to cytoskeletal actin filaments. Taken together, these data demonstrate that SM22beta is a novel actin-associated protein with a unique cell lineage-restricted pattern of expression.