Quantitative multivariate analysis of myoepithelioma and myoepithelial carcinoma

The nuclear DNA content and morphologic data of 30 surgical samples (eight normal parotid gland, 12 myoepithelioma, and 10 myoepithelial carcinoma) were analyzed by the IBAS II analysis system. The results suggest that there are relationships between tumor ploidy distribution and prognosis, and that correct pathologic diagnosis can be obtained by the IBAS image system.

[Abnormal expression and clinical significance of mutation p53 gene on human bladder cancer]

In order to study the relationships between the mutant p53 gene and human bladder cancer, the authors used in situ hybridization to detect 30 of bladder cancer and 4 of normal bladder samples. The results showed that p53 gene positive rate of mRNA was 23.3% in cancer patient, and all negative in normal-bladder. The positive rate was significantly different in pathological grading and clinical stages of carcinoma (P < 0.05). It suggests that the mutant p53 gene participats in transformation of carcinoma and may be used as a tumor marker for determinating invasiveness and prognosis of bladder carcinoma.

[Histogenesis of pleomorphic adenoma of the salivary gland]

Six parotid pleomorphic adenomas were studied histochemically by electron microscopy after staining with ruthenium red. It was found that the myxoid region was filled with ruthenium red granules. Similar positive ruthenium red-stained intracellular granules were observed within the Golgi-derived vacuoles of the neoplastic myoepithelial cells in the myxoid region. Some cells located at the periphery of the double-layer ductal structure had the features of myoepithelial cell, they also showed similar positive ruthenium red-stained granules in the intracellular vacuoles and intercellular space. No ruthenium red-stained granules was obtained in neoplastic ductal epithelium and the mucus in ductal cavities were negative for ruthenium red stain. The observations indicate that the neoplastic myoepithelial cells in the myxoid region probably derive from the periphery of the double-layer ductal structure, they secrete the proteoglycans forming the myxoid region and play an important role in the histogenesis of pleomorphic adenoma.

Plasminogen activator inhibitor type 2: an intracellular keratinocyte differentiation product that is incorporated into the cornified envelope

Human epidermal keratinocytes synthesize a complex plasminogen activator proteolytic cascade, consisting of two plasminogen activating enzymes and two inhibitors, that is thought to play a role in epidermal migration and differentiation as well as in several cutaneous diseases. Quantification of the plasminogen activator cascade proteins in keratinocytes reveals that plasminogen activator inhibitor type 2 (PAI-2) is distinct from the other components (i.e., urokinase and tissue-type plasminogen activators and inhibitor type 1) in several respects: (i) PAI-2 remains mostly cell-associated, rather than secreted; (ii) The level of cell-associated PAI-2 is at least 50-fold greater than that of the other components; (iii) PAI-2 is the only component whose level is enhanced upon elevation of the Ca2+ concentration, which is well known to induce a more differentiated phenotype in keratinocyte culture. Immunocytochemical localization experiments reveal that most keratinocytes contain PAI-2, which in a subpopulation of more differentiated cells is resistant to detergent extraction. Additional immunocytochemical localization and immunoblot experiments demonstrate that some of the PAI-2 becomes incorporated into the cornified envelope during terminal differentiation of the keratinocyte. These studies raise the possibility that PAI-2 may have an intracellular role associated with the terminal stage of keratinocyte differentiation.

Holographic recording and light amplification in doped polymer film

We reported an experimental study of holographic recording and signal light amplification through higherorder diffracted waves from holographic gratings recorded in an acceptor-donor-substituted azobenzene-doped poly(methyl methacrylate) thin film.

Subinhibitory concentrations of antibiotics affect cell surface properties of Streptococcus sobrinus

Several antibiotics, at subinhibitory concentrations, caused an increase in the ability of Streptococcus sobrinus to bind alpha-1,6-glucans, whereas other antibiotics decreased glucan binding. In every case, glucan binding was inversely proportional to cell surface hydrophobicity. High levels of glucan-binding activity resulted in low levels of hydrophobicity, whereas low levels of glucan binding caused high levels of cellular hydrophobicity. The results show that low concentrations of antibiotics may modulate lectin and hydrophobin adhesins in streptococci.

Impact of polyamine analogues on the NMDA receptor

Several N,N'-terminal dialkylated homologs of the tetraamine spermine exhibit a pronounced biphasic activity at the N-methyl-D-aspartate (NMDA) receptor-channel complex in rat cerebral cortex membranes in the presence of 100 microM L-glutamate and 100 microM glycine. At low micromolar polyamine concentrations, these analogs enhance binding of [3H]-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-im ine ([3H]MK-801) similar to spermine (SPM). At higher concentrations (e.g., > or = 10 microM), the analogs are antagonists of [3H]MK-801 binding. The most potent analog, N1,N14-bis(1-adamantyl)homospermine, is almost totally devoid of agonist activity and is a potent antagonist at concentrations > or = 5 microM. Three structural features of the tetraamines studied appear to correlate with potency of inhibition: (1) N-terminally alkylated polyamines > terminal primary amines (e.g., SPM); (2) length of the polyamine backbone, e.g., DMHSPM > DMNSPM; and (3) size of the terminal alkyl groups, i.e., adamantyl > tert-butyl > ethyl > methyl. These findings emphasize the potential of the tetraamine backbone as a pharmacophore to modulate NMDA receptor-channel function.

Effect of Chloramphenicol on Denitrification in Flexibacter canadensis and "Pseudomonas denitrificans"

It was recently reported that chloramphenicol inhibits existing denitrification enzyme activity in sediments and carbon-starved cultures of "Pseudomonas denitrificans." Therefore, we studied the effect of chloramphenicol on denitrification by Flexibacter canadensis and "P. denitrificans." Production of N(inf2)O from nitrate by F. canadensis cells decreased as the concentration of chloramphenicol was increased, and 10.0 mM chloramphenicol completely inhibited N(inf2)O production. "P. denitrificans" was less sensitive to chloramphenicol, and production of N(inf2)O from nitrate was inhibited by only about 50% even in the presence of 10.0 mM chloramphenicol. These results suggested that inhibition of denitrification enzyme activity depended on the concentration of chloramphenicol. Increasing the concentration of chloramphenicol decreased the rate of production of nitrite from nitrate by F. canadensis cells, and the concentration of chloramphenicol which resulted in 50% inhibition of production of nitrite from nitrate was 2.5 mM. In contrast, the rates of production of nitrite from nitrate by intact cells and cell extracts of "P. denitrificans" were inhibited by only 58 and 54%, respectively, at a chloramphenicol concentration of 10.0 mM. Chloramphenicol caused accumulation of NO from nitrite but not from nitrate and inhibited NO consumption in F. canadensis; however, it had neither effect in "P. denitrificans." Chloramphenicol did not affect N(inf2)O consumption by these organisms. We concluded that chloramphenicol inhibits denitrification at the level of nitrate reduction and, in F. canadensis, also at the level of NO reduction.

[Expression of proliferating cell nuclear antigen (PCNA) in squamous cell carcinoma of the oral cavity]

Proliferating cell nuclear antigen (PCNA) was identified by immunohistochemistry in 52 cases. PCNA-positive cells had been detected in the basal cells of normal epithelium known to contain proliferating cells. PCNA scores of normal epithelium was 1 as "low", and carcinomas were 3 or 4 as "high". The PCNA scores of high-grade carcinoma was significantly higher than the low-grade carcinoma. The study shows that expression of PCNA correlated with carcinoma grade.

Construction and characterization of a human chromosome 2-specific BAC library

We have constructed a human chromosome 2-specific bacterial artificial chromosome (BAC) library using DNA from the somatic cell hybrid GM10826. The average size of the clones is about 63 kb. The coverage and distribution of the library were estimated by screening with known polymorphic genetic markers and fluorescence in situ hybridization (FISH). Twenty-one markers tested positive when DNA pools prepared from approximately one-sixth of the library were screened with 33 known markers. This is consistent with the theoretical calculation of 63% coverage at one genomic equivalent. This suggested that the coverage of the library is approximately 5-6x. FISH analysis with 54 BACs revealed single site hybridization to chromosome 2, and the clones were distributed randomly on the chromosome. We have also performed direct sequencing of the BAC insert ends to generate sequence-tagged sites suitable for mapping and chromosome walking. This is the first reported human chromosome 2-specific BAC library and should provide a resource for physical mapping and disease searching for this chromosome.

Materials for birefringent coatings

We discuss recent developments in methods for monitoring the anisotropic growth and properties of tilted columnar films and present results for the perpendicular incidence birefringence of aluminum oxide, Merck Substance Hi, silicon oxide, tantalum oxide, titanium oxide, and zirconium oxide.

Transfer of human chromosome 3 to an ovarian carcinoma cell line identifies three regions on 3p involved in ovarian cancer

The molecular pathogenesis of ovarian carcinoma involves altered expression of growth factors, activation of oncogenes and loss of tumor suppressor genes. Loss of heterozygosity on chromosomes 3p, 6q, 11p, 17 and 18q was reported as a significant alteration in ovarian cancer. However, no functional proof has been provided of tumor suppressor activity located in these chromosomal regions. We therefore introduced normal human chromosomes 3 and 11 into an ovarian carcinoma cell line by microcell mediated chromosome transfer. Transfer of chromosome 3 induced senescence and growth arrest as well as suppression of tumorigenicity. Tumors induced by chromosome 3 monochromosomic hybrids consistently lost three small regions on 3p, two of which located in 3p23-24.2 and one located in 3p21.1-21.2, suggesting that these chromosomal regions are important for suppression of tumorigenicity of ovarian carcinoma cells. Transfer of chromosome 11 reduced the in vitro growth properties of ovarian cancer cells but did not significantly affect tumorigenicity. These results provide functional evidence for chromosome 3 tumor suppressor activity in ovarian cancer and define the chromosomal regions on 3p involved in the pathogenesis of this tumor. This experimental system, based on functional effects, may be useful for further delimitation and isolation of critical regions on 3p involved in tumor suppression.

Integration of traditional and modern methods in the identification of AFB cultures isolated from clinical specimens of patients with skin diseases

This article reports the identification of 57 AFB cultures isolated from clinical specimens by using traditional methods (TM, including biochemical and cultural methods) and modern ELISA with monoclonal antibody (McAb-ELISA) and nested primer gene amplification assay (NPGAA). The representive AFB culture M. A1, A7, A19, A21 and A22) isolated from human lepromas were identified as new species by TM and it was shown that they were not identical to M. leprae by McAb-ELISA and NPGAA. Among another set of samples (M. S17, S1, S2, S2R, S7, S29), M. S17 was identical to M. scrofulaceum as assessed by TM only, while the others were found to be similar to M. tuberculosis and different from M. leprae using TM and McAb-ELISA, and identical to M. tuberculosis with NPGAA. The authors conclude that TM and MM are very useful for identifying mycobacteria, while MM was much more sensitive and specific than TM. The selection and use of these methods depends on practical need.

Charge state specific facile gas-phase cleavage of Asp 75-Met 76 peptide bond in the alpha-chain of human apohemoglobin probed by electrospray ionization mass spectrometry

Herein, we present the first example of charge state specific facile gas-phase cleavage of an aspartic acid-methionine peptide linkage. This cleavage (Asp 75-Met 76) was observed in the alpha-chain of human adult hemoglobin (Hb) and was probed by electrospray ionization mass spectrometry. This specific conformational and/or charge density dependent dissociation was observed primarily in the [M + 11H]11+ and [M + 12H]12+ species. A mechanism involving an intramolecular proton transfer from the protonated carboxyl side chain of Asp 75 to the neighboring Met 76 residue yielding an anhydride moiety at the C-terminal of the Asp 75 is proposed. Dramatic differences in dissociation of [M + 13H]13+ and [M + 14H]14+ species were observed.

Antiproliferative properties of polyamine analogues: a structure-activity study

A basis set of polyamine analogues was designed and synthesized. These compounds were used to initiate a systematic investigation of the role of chain length, terminal nitrogen alkyl group size, and symmetry of the methylene backbone in the antineoplastic properties of polyamine analogues. New synthetic methods predicated on our earlier polyamine fragment synthesis are described for accessing the tetraamines of interest. An unsymmetrically substituted diamine reagent, N-(tert-butoxycarbonyl)-N,N'-bis(mesitylenesulfonyl)-1,4-diaminobu tane, was developed for entry into unsymmetrical tetraamines. All of the tetraamines synthesized were first evaluated in a murine leukemia L1210 cell IC50 assay at 48 and 96 h. In an attempt to correlate this behavior with some aspect of polyamine metabolism, each compound was tested for its ability to compete with spermidine for the polyamine uptake apparatus, its impact on the polyamine biosynthetic enzymes ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (AdoMetDC), and its effect on the polyamine-catabolizing enzyme spermidine/spermine N1-acetyltransferase (SSAT) and on polyamine pools. While there was no obvious correlation between the 48 and 96 h IC50's and the impact of the analogues on polyamine metabolism, there were other structure-activity relationships. Correlations were observed to exist between chain length and IC50's and between terminal alkyl substituents and impact on Ki, ODC, and AdoMetDC. Also, preliminary studies suggest a relationship may exist between the 48 and 96 h IC50 activities and the analogue's chronic toxicity in vivo. Finally, when the overall length of the polyamine backbone was held constant, the symmetry of the methylene chains of the polyamine fragments was shown to be unimportant to the compound's activity.

[Evaluation of two glycolipids from M. tuberculosis in the serodiagnosis of tuberculosis]

Sera from 112 healthy controls and 120 pulmonary tuberculous patients (61 untreated patients and 59 active patients) were assayed, by ELISA, to test the activity of IgG and IgM antibodies against antigen of 2, 3-diacyl-trehalose-2'-sulphate (SL IV) a phenolglycolipid antigen (PGLTb1) and purified protein derivative (PPD) from M. tuberculosis. Respectively, for SL IV-IgG-ELISA, SL IV-IgM-ELISA, PGLTb1-IgG-ELISA, PGLTb1-IgM-ELISA, PPD-IgG-ELISA, the specificities were of 96.43, 96.43, 96.43, 96.43 and 95.53%; the sensitivities were of 51.67, 32.50, 14.17, 18.33 and 33.33%; the efficiencies were of 73.28, 63.36, 53.88, 56.03 and 62.93%; the predictive values for a positive result were of 96.87, 86.67, 80.95, 84.62 and 88.64%. Among the three antigens tested, SL IV was found to be better than PGLTb1 and PPD.

Cardiorespiratory responses to low-intensity heart rate-controlled exercise in female subjects

This study compares selected cardiorespiratory responses of six healthy females during exercise on rowing (R), cycle (C) and arm (A) ergometers. Their mean +/- sd age, mass and height were 22.3 +/- 3.0 years, 55.3 +/- 6.3 kg and 161.5 +/- 7.4 cm, respectively. Subjects reported to the laboratory on three separate days without engaging in intense physical activity the day prior to testing. Subjects sat quietly for five minutes on an ergometer prior to a 15 minute, steady-state exercise bout. Target heart rate during the exercise period was set at 115 bpm, and was monitored continually with workload adjustments applied to the ergometers to ensure that the target rate was maintained. CO2 rebreathing using the Sensormedics Horizon MMC was performed twice at steady-state exercise and averaged to examine changes in Q and SV. A one-way repeated measures ANOVA revealed that at similar levels of heart rate (R = 114.0 +/- 2.8; C = 116.0 +/- 2.8; A = 114.8 +/- 6.9 bpm) there were significantly lower Q and SV during arm ergometry (8.43 +/- 0.93 l/min and 72.61 +/- 7.82 ml) than rowing (13.01 +/- 1.61 l/min and 111.57 +/- 13.52 ml) and cycle (11.10 +/- 2.19 l/min and 88.23 +/- 21.94 ml) ergometry, and there were no significant differences in Q and SV between rowing and cycling. These results suggest that arm work during low intensity steady-state aerobic exercise is associated with a reduced stroke volume which is probably related to a reduced venous return during arm work in comparison to other types of exercise.

Protein kinase C activation inhibits cytokine-induced nitric oxide synthesis in vascular smooth muscle cells

Vascular smooth muscle cells (SMC) respond by relaxation to nitric oxide (NO) released from the endothelium which expresses a constitutive, Ca(2+)-dependent NO synthase (cNOS). SMC can, however, produce NO themselves upon stimulation by proinflammatory cytokines which induce expression of an inducible, Ca(2+)-independent NO synthase (iNOS). Protein kinase C represents another important second messenger system involved in the regulation of SMC contraction. We have investigated iNOS expression and NO synthesis in rat vascular SMC treated with the cytokines, IFN gamma and TNF alpha, in the presence or absence of the activator of protein kinase C, beta-phorbol-12-myristate 13-acetate (PMA). Treatment with PMA did not induce any significant accumulation of nitrite, a major stable metabolite of NO, in SMC. When added simultaneously with the cytokines, PMA significantly reduced nitrite accumulation induced by cytokine stimulation in a dose-dependent fashion. This inhibitory effect was mediated by activation of PKC since calphostin C, a specific PKC inhibitor, abolished the PMA effect. Further analysis of iNOS mRNA with a rat iNOS cDNA probe demonstrated that addition of PMA reduced expression of SMC iNOS mRNA, indicating that the antagonism in induction of NO synthesis between PMA and the proinflammatory cytokines acts on the transcriptional level. The inhibitory effect of PMA may be mediated via induction of a suppressor of iNOS expression, since pretreatment with PMA reduced NO production after subsequent treatment with cytokines. These observations suggest that activation of the PKC pathway is involved in a negative regulation of iNOS gene expression and this is compatible with the observation that vascular SMC contraction can be induced by PKC activation.

Enterokinase, the initiator of intestinal digestion, is a mosaic protease composed of a distinctive assortment of domains

Enterokinase is a protease of the intestinal brush border that specifically cleaves the acidic propeptide from trypsinogen to yield active trypsin. This cleavage initiates a cascade of proteolytic reactions leading to the activation of many pancreatic zymogens. The full-length cDNA sequence for bovine enterokinase and partial cDNA sequence for human enterokinase were determined. The deduced amino acid sequences indicate that active two-chain enterokinase is derived from a single-chain precursor. Membrane association may be mediated by a potential signal-anchor sequence near the amino terminus. The amino terminus of bovine enterokinase also meets the known sequence requirements for protein N-myristoylation. The amino-terminal heavy chain contains domains that are homologous to segments of the low density lipoprotein receptor, complement components C1r and C1s, the macrophage scavenger receptor, and a recently described motif shared by the metalloprotease meprin and the Xenopus A5 neuronal recognition protein. The carboxyl-terminal light chain is homologous to the trypsin-like serine proteases. Thus, enterokinase is a mosaic protein with a complex evolutionary history. The amino acid sequence surrounding the amino terminus of the enterokinase light chain is ITPK-IVGG (human) or VSPK-IVGG (bovine), suggesting that single-chain enterokinase is activated by an unidentified trypsin-like protease that cleaves the indicated Lys-Ile bond. Therefore, enterokinase may not be the "first" enzyme of the intestinal digestive hydrolase cascade. The specificity of enterokinase for the DDDDK-I sequence of trypsinogen may be explained by complementary basic-amino acid residues clustered in potential S2-S5 subsites.

Comparison of standard locked-ward treatment versus open-ward rehabilitation treatment for chronic schizophrenic patients. A one-year controlled trial in Canton

A priority for psychiatric rehabilitation workers in China is to develop less-restrictive methods for managing the estimated 2500 chronically institutionalised patients who are symptomatically stable and have adequate psychosocial functioning but have no family members who are able or willing to take them home. We transferred 45 chronic schizophrenic male in-patients to an open-door rehabilitation ward where they were given as much freedom as possible and encouraged to take part in occupational, social, and recreational activities. The Nurses Observation Scale for Inpatient Evaluation (NOSIE) was used to compare the psychosocial functioning of the 43 patients who completed the year-long trial with that of 43 similar patients who received standard in-patient treatment on a locked ward. Over the year, the experimental group showed a significant improvement in overall functioning, whereas the control group showed no improvement. These findings suggest that open-door rehabilitation wards situated within the hospital can mobilise latent psychosocial functioning and may be a good method for re-introducing chronic schizophrenic patients in China back into the community.

Cellular regulation of nitrate uptake in denitrifying Flexibacter canadensis

Nitrate uptake and its regulation were investigated using an ion-specific nitrate electrode for denitrifying Flexibacter canadensis under anaerobic conditions. Glucose supported a greater rate of nitrate uptake than did glycerol, glutamate, lactose, cellobiose, or ethanol. Nitrate uptake closely approximated Michaelis--Menten kinetics; the estimated Ks(glucose) and apparent Km(nitrate) for nitrate uptake were 21 and 44 microM, respectively. Nitrate disappearance was correlated with nitrite accumulation, and nitrate had an inhibitory effect on nitrite reduction. Oxygen inhibition of nitrate uptake increased as the percent air saturation increased, and reversed readily as the percent air saturation decreased. The minimal air saturation showing inhibition of nitrate uptake was about 2-4%. Azide and cyanide completely inhibited nitrate uptake. No nitrate uptake was observed in cells grown in the presence of 1 or 5 mM tungstate (no added molybdate). When molybdate (100-200 microM) was present in the medium, nitrate uptake was exhibited by organisms grown with 1 mM, but not with 5 mM, tungstate, indicating that nitrate uptake was dependent on the presence of an active nitrate reductase, and that competition between tungsten and molybdenum occurred during the formation of nitrate reductase. Nitrite production from nitrate by whole cells but not cell-free extracts was inhibited by 2,4-dinitrophenol and carbonyl cyanide m-chlorophenylhydrazone, indicating that nitrate and (or) nitrite transport depended upon the electrochemical proton gradient.

[Study on antibacterial protein from human urinary bladder mucosa]

Acid-soluble extract of human bladder mucosal surface was obtained by washing out the bladder of accidentally dead male human with 1% acetic acid in the presence of proteinase inhibitors. Acid urea polyacrylamide gel electrophoresis (AU-PAGE) indicated that the acid-soluble extract had more than 10 main protein bands, but the currently known antibiotic peptides, e. g., Lysozyme and defensins, were not found in this extract. The quantitation assay of lysozyme showed that lysozyme only amounted to 2.2 microgram per milligram protein. When tested for antibacterial activity by using ultrasensitive radial diffusion assay, the acid-soluble extract effectively killed E. coli ML-35P. The antibacterial activity of the acid-soluble extract was further analysed by gel overlay technique and the result showed that one main protein band, which was referred to as human bladder protein (HBP), was potently antibacterial against E. coli ML-35P. The HBP accounted for 4% of the total acid-soluble extract protein. These results suggest that the presence of antibacterial protein in the bladder mucosa may be the molecular base of the bladder antibacterial defence mechanisms.

Among a range of transition metals and ligands vanadium.desferroxamine excels in accelerating reactivity of ferrocytochrome c toward molecular oxygen

Despite early knowledge of the requirement for metals in the reactions of ferrocytochrome c with oxygen, the relative effectiveness of metals and the factors that modulate effectiveness remain unknown. We have compared the catalytic power of five metals and report the effects of pH and ligand on their effectiveness as catalysts. Catalysis by metal ions was greatest at higher pH, where the rate of aerobic oxidation was lowest. Iron (Fe2+), copper (Cu2+), vanadium(V) (V(V)), manganese (Mn2+), and aluminum (Al3+) were tested in combination with EDTA, ADP, histidine, or desferrioxamine (Des) at pH 2.6, 3.2, and 4.0. At pH 2.6, only vanadium(V) increased the initial rate of the oxidation of ferrocytochrome c (by 6.2-fold). At pH 4.0, however, all the metals markedly stimulated the oxidation of cytochrome c. The order of effectiveness was V(V).Des >> Cu.ADP2+ > Fe.EDTA2+ > Mn.Des2+ > Al.EDTA3+ (where the stated ligand represents the most stimulating one for a given metal). At pH 3.2 the metal complexes had intermediate effects, with vanadium again being the most effective. The preeminence of vanadium among the metals is novel. Where the heme crevice is closed (pH 4), transition metal ions mediated almost all of the reduction of oxygen, while at the lowest pH (2.6) transition metal ions were largely unnecessary. Vanadium(V) was the most active of the metals at all values of pH and the only metal to accelerate the oxidation of ferrocytochrome c at pH 2.6. Understanding of the range of biological actions of vanadium will not be complete without a knowledge of its redox reactivity within the components of biological systems.