MALLORY BODY-LIKE STRUCTURES IN THE LUNG

Mallory body-like structures (MBLs), which resemble Mallory body (MB) in the liver, were observed in lungs of 4 cases showing interstitial pneumonitis. MBLs were found in the cytoplasm of especially swollen alveolar epithelial cells. MBLs and MBs had almost similar characteristics morphologically and tinctorially under the light microscopy. MBLs were composed of intermediate type fine fibrils which were positive for anti-keratin antibody. These findings suggested that MBLs were a kind of pathological keratinization of alveolar epithelial cells. Although the origin of MBL containing cells could not be clarified, they were closely related to type 2 alveolar epithelial cells.     

Development of Harderian gland during metamorphosis in anurans

Development of Harderian gland of larvae of Rana japonica, Bufo bufo japonicus, and Xenopus laevis was studied. In the adult animals, well-developed Harderian glands were invariably present in the orbit. In Rana and Bufo, the gland first appeared at late prometamorphic stage and in Xenopus it appeared around climax stage. In thyroidectomized tadpoles of Bufo and Rana, the Harderian gland was induced by thyroxine. In hypophysectomized tadpoles of Bufo the gland developed when they were treated with thyroxine or TSH.     

Optimization of nonviral transfection: variables influencing liposome-mediated gene transfer in proliferating vs. quiescent cells in culture and in vivo using a porcine restenosis model

Cationic liposomes/DNA complexes are widely used vectors for delivering genes in clinical and experimental trials. Relatively low transfer efficiencies in vivo compared with viral gene transfer may be improved using local application. In addition, markedly increased transfer efficiency may be achieved in vitro and in vivo via optimization of known variables influencing liposomal transfection. Lipofection under different conditions was performed in various cell lines and primary porcine smooth muscle cells. Optimized conditions found in vitro were verified in vivo using a porcine restenosis model. Toxicity was monitored analyzing cell metabolism. Transfer efficiency and safety were determined using morphometry, histology, galactosidase assays, PCR, and RT-PCR. The most important variables enabling maximum transfer efficiency were firstly the appropriate selection of cationic lipids for the cell type to be transfected, secondly the DNA/liposome ratio chosen, which depended on the cell type and cationic lipids used, and thirdly the state of proliferation of the targeted cells. Transfection in vivo demonstrated two- to fivefold higher transfer efficiencies when transfer conditions were extrapolated from optimization experiments in stationary cells compared with the use of conditions established in proliferating cells. Application of the therapeutic gene for cecropin using optimized transfer conditions resulted in a significantly reduced neointima formation compared with the transfection using a control gene for ss-galactosidase. Thus, in this vascular model, initial optimization of lipofection in stationary cells in culture followed by local delivery in vivo and with selection of a suitable therapeutic gene led to markedly improved transfer efficiencies, gene expression, and biological effect. Stationary cell cultures simulate more realistically the in vivo situation and may therefore represent a better model for future in vivo experiments. In addition, the advantages of liposomes are easy handling, low toxicity, and the lack of carcinogenicity or immunogenic reactions.     

Ascending and descending components of the medial forebrain bundle in the rat as demonstrated by the horseradish peroxidase-blue reaction

Summary The ascending and descending components of the medial forebrain bundle (MFB) were investigated by means of horseradish peroxidase (HRP) with a sensitive substrate. The HRP was injected iontophoretically into the MFB at various levels from the anterior commissure to the posterior hypothalamus. In order to prevent the diffusion of HRP to other brain areas, a double micropipette system was used. The descending components of the MFB are derived from (1) the anterior cingulate area, infra- or prelimbic area, and sulcal cortex, (2) the lateral septal nucleus and diagonal band, (3) the bed nucleus of the stria terminalis, (4) the paraventricular nucleus (5) the substantia innominata, (6) the amygdaloid complex (AM), (7) the ventromedial (VM) and dorsomedial (DM) hypothalamic nuclei, (8) the entopeduncular nucleus and (9) nucleus periventricularis stellatocellularis. The ascending components of the MFB originate in: (1) the medial preoptic nucleus, (2) the nucleus periventricularis stellatocellularis and rotundocellularis, (3) the posterior hypothalamic nucleus, (4) the parafascicular nucleus, (5) the ventral premammillary nucleus, (6) the substantia grisea periventricularis, (7) the lateral habenular nucleus, (8) the VM and DM, (9) the paratenial nucleus, (10) the AM and (11) the arcuate nucleus.Abbreviations used in Figures and Tables a nucleus accumbens - abl nucleus amygdaloideus basalis, pars lateralis - abm nucleus amygdaloideus basalis, pars medialis - ac nucleus amygdaloideus centralis - AC anterior cingulate area - al nucleus amygdaloideus lateralis - am nucleus amygdaloideus medialis - ar nucleus arcuatus - CC tractus corporis callosi - CSDV commissura supraoptica dorsalis, pars ventralis - DB diagonal band - DM nucleus dorsomedialis hypothalami - EP nucleus entopeduncularis - ha nucleus anterior hypothalami - hl nucleus lateralis hypothalami - hp nucleus posterior hypothalami - IL infralimbic area of frontal cortex - lh nucleus habenulae lateralis - LH₁ medial forebrain bundle (MFB) at the level of commissura anterior - LH₂ lateral preoptic area - LH₃ MFB at the level of the nucleus anterior hypothalami - LH₄ MFB at the level of the nucleus ventromedialis hypothalami - LH₅ MFB at the level of the nucleus posterior hypothalami - MFB medial forebrain bundle - pf nucleus parafascicularis - PL prelimbic area of frontal cortex - pol nucleus preopticus lateralis - pom nucleus preopticus medialis - posc nucleus preopticus, pars suprachiasmatica - pt nucleus parataenialis - pv nucleus premamillaris ventralis - PV nucleus paraventricularis - pvs nucleus periventricularis stellatocellularis - pvr nucleus periventricularis rotundocellularis - SC sulcal cortex - SGPV substantia grisea periventricularis - SI substantia innominata - SL lateral septal nucleus - ST bed nucleus of stria terminalis - sum nucleus supramamillaris - TO tractus opticus - tmm nucleus medialis thalami, pars medialis - VM nucleus ventromedialis hypothalami The nomenclature used in this paper is according to König and Klippel's Stereotaxic Atlas (1967).     

Regulation of Th2 cell differentiation by mel-18, a mammalian polycomb group gene

Polycomb group (PcG) gene products regulate homeobox gene expression in Drosophila and vertebrates and also cell cycle progression of immature lymphocytes. In a gene-disrupted mouse for polycomb group gene mel-18, mature peripheral T cells exhibited normal anti-TCR-induced proliferation; however, the production of Th2 cytokines (IL-4, IL-5, and IL-13) was significantly reduced, whereas production of IFNgamma was modestly enhanced. Th2 cell differentiation was impaired, and the defect was associated with decreased levels in demethylation of the IL-4 gene. Significantly, reduced GATA3 induction was demonstrated. In vivo antigen-induced IgG1 production and Nippostrongylus brasiliensis-induced eosinophilia were significantly affected, reflecting the deficit in Th2 cell differentiation. Thus, the PcG gene products play a critical role in the control of Th2 cell differentiation and Th2-dependent immune responses.     

Mold filling of titanium alloys in two different wedge-shaped molds

Pure titanium and titanium alloys are potential materials for the fabrication of cast dental appliances. One important factor in producing sound castings is the capacity of the metal to fill the mold. This study used a wedge-shaped mold to compare the mold filling of titanium with that of conventional dental casting alloys. The metals used were CP Ti, Ti-6Al-7Nb, Ti-6Al-4V, Ti with 1 and 4wt% Cu and ADA Type III gold alloy and an Ni-Cr alloy. The castings were cut into four pieces parallel to the triangular surface. Mold filling was evaluated as the distance between the tip of the cast wedge and theoretical tip of the triangle. The mold filling of the gold alloy was superior compared to all the metals tested, while the mold filling of the Ni-Cr alloy was the worst. There were no statistical differences at the 30 degrees marginal angle for all the cast titanium metals. At the sharper 15 degrees angle, CP Ti and Ti-6Al-7Nb was superior to both the Ti-Cu alloys. Although the mold filling of titanium was inferior compared to the gold alloy, the data justify the use of titanium for the production of dental appliances.     

Development of a new calcium phosphate cement that contains sodium calcium phosphate

A cement powder consisting of sodium calcium phosphate, Na3Ca6(PO4)5, in addition to tetracalcium phosphate and beta-tricalcium phosphate was prepared by pulverizing blocks of 4 wt% sodium-, 11 wt% carbonate-containing apatite samples that were heated at 1700 degrees C for 5 h. When mixed with 30 wt% malic acid or citric acid at a powder liquid ratio of 3:1, the cement set in 3 or 7 min at room temperature with compressive strength being around 52 or 27 MPa. In HeLa-cell cultures, the cement mixed with malic acid was less cytotoxic than the cement mixed with citric acid, which was far less cytotoxic than a commercial carboxylate cement used as a negative control, suggesting malic acid to be superior to citric acid as a liquid in this regard. Similar findings were also obtained with osteoclasts, of which culture experiments clearly suggested that the number of osteoclasts on the cement mixed with malic acid was significantly greater than that on the cement mixed with citric acid. Since osteoclastic response to substrates could be used as a maker in evaluating their bioresorbability associated with osteoclasts, the above finding may suggest that the cement that is to be mixed with malic acid would be more useful as bone substitutes.