The purification and properties of NADPH-dependent carbonyl reductases from rat ovary

Two carbonyl reductases have been highly purified from rat ovary to apparent homogeneity. Though they have similarities in terms of molecular weight (33,000), substrate specificities, inhibitor sensitivities, amino acid composition, and immunological properties, they differed in pI values (6.0 and 5.9). Both enzymes reduced aromatic aldehydes, ketones, and quinones at higher rates, compared to prostaglandins and 3-ketosteroids, whereas they showed higher affinity for prostaglandins and 3-ketosteroids. The enzymes also catalyzed oxidation of the 9-hydroxy group of prostaglandin F2 alpha. Moreover, they showed the remarkable characteristic of catalyzing the reduction of not only the 9-keto group of prostaglandin E2 but also the 15-keto group of 13,14-dihydro-15-keto-prostaglandin F2 alpha. Both enzymes were inhibited by SH-reagents, quercitrin, indomethacin, furosemide, and disulfiram. The results of immunoinhibition, using antibody against the purified enzymes, indicated that the enzymes were solely responsible for the overall catalytic activities of prostaglandin E series reduction, as well as 13,14-dihydro-15-keto-prostaglandin F2 alpha reduction and prostaglandin F2 alpha oxidation in rat ovarian cytosol. Western-blot analysis revealed that immunoreactive proteins were present in adrenal gland and various reproductive tissues except uterus of rats.     

Cytologic appearance of carcinosarcoma (malignant ameloblastoma and fibrosarcoma) of the maxilla. A case report.

The cytologic appearance of a carcinosarcoma (malignant ameloblastoma and fibrosarcoma) of the maxilla in a 63-year-old man is described. On his first admission the diagnosis of malignant ameloblastoma was made on biopsy. After five surgical excisions, radiotherapy and chemotherapy, the diagnosis was changed to carcinosarcoma because the stromal cells of the tumor had become malignant. Aspiration biopsy cytology of the tumor, with a cystic lesion found at the left suborbital area, revealed malignant epithelial cells, indicating malignant ameloblastoma. Imprint smears of both surgically resected and autopsy material showed two types of malignant neoplastic cells, of epithelial and mesenchymal origin.     

Selective inhibition of MAO-A in serotonergic synaptosomes by two amphetamine metabolites, p-hydroxyamphetamine and p-hydroxynorephedrine

The present study was carried out mainly to clarify whether the two amphetamine metabolites, p-hydroxyamphetamine (P-OHA) and p-hydroxynorephedrine (p-OHN) are taken up by mouse brain 5-hydroxytryptamine (5-HT) nerve terminals to inhibit type A monoamine oxidase (MAO-A) and then potentiate the abnormal behavior, head-twitch. Of the two metabolites, only intracerebroventricular p-OHA, at 80 μg/mouse, sufficient to cause a head-twitch response (HTR), appreciably inhibited MAO-A activity without affecting MAO-B activity in homogenates of the mouse striatum, hypothalamus and the rest of the forebrain; and p-OHN did not inhibit either type of MAO at the dose tested. Estimation of intra- and extrasynaptosomal MAO-A activity showed that both metabolites significantly inhibited only the intrasynaptosomal deamination of 5-HT by MAO-A with p-OHA being more potent. Taken together with our previous findings, these present results clearly indicate that p-OHA may accumulate in the 5-HT nerve terminals through the uptake system, and concomitantly inhibit MAO-A activity. These actions of p-OHA may increase intraneuronal 5-HT levels and then potentiate 5-HT release to cause interaction with the post-synaptic 5-HT receptors.     

Hormonal stimulation of tyrosinase activity in human foreskin organ cultures

Summary A human foreskin organ culture system has been developed to study the response of human skin to hormonal stimulation. Foreskins are maintained in culture on floating plastic supports which allows the epidermal surface to be exposed to air while the dermis is bathed in nutrient medium. Both black and white human foreskins can be maintained in organ culture for at least 1 wk with no change in the tissue structure or cell viability as determined by histochemical staining and by dopa reaction staining. Tyrosinase activity in both black and white human foreskin cultures decays markedly during the first 2 d of culture to a new steady state level which remains stable throughout the culture period. Both black and white foreskin cultures consistently demonstrate 2- to 10-fold increases in tyrosinase activity when treated with theophylline (1 mM). Approximately 90% of all skin cultures examined showed an increase in enzyme activity when treated with this phosphodiesterase inhibitor. Dibutyryl cAMP (0.1 mM) and [Nle⁴, D-phe⁷]-alpha MSH (10⁻⁸ M), were also found to markedly stimulate tyrosinase activity in some skin cultures, whereas alpha-MSH and prostaglandin E₁ produced only an inconsistent and small increase in the activity of the enzyme. Histamine (1 μM), vitamin D₃ (1 μM), and retinoic acid (1μM) failed to stimulate tyrosinase activity in either white or black foreskin cultures. This hormone-responsive organ culture system can be utilized to characterize the molecular processes responsible for the regulation of tyrosinase and pigmentation in human skin. This work was supported by a research contract from the Oklahoma Center for the Advancement of Science and Technology (OCAST) and by a research grant from the Presbyterian Health Foundation.     

Resuscitation of Vibrio cholerae O1 strain TSI-4 from a viable but nonculturable state by heat shock

Abstract Vibrio cholerae strain TSI-4 was incubated in an M9 salt solution at 15 °C for more than 100 days. The plate counts showed no viable cells on day 30, but a broth culture from that day showed the growth of bacteria. However, after 35 days the bacteria entered the nonculturable state, based on the assessment of both the plate counts and broth culture. A portion of the culture was heated at 45 °C for 1 min in a water bath and subsequently plated onto a nutrient agar plate. More than 1000 colonies were recovered after this heat-shock treatment. The recovered cells showed the same chromosomal DNA pattern in the restriction map and the same outer membrane protein pattern in SDS-PAGE. Recovery of viable cells by heat-shock was achieved in cultures grown on M9 salt but not from cultures grown in phosphate-buffered saline. This suggests that the presence of NH₄Cl in the M9 salt solution may support the growth of the bacteria in a low nutrient medium, while also playing an important role in resuscitation.     

Transformation of cucumber (Cucumis sativus L.) plants using Agrobacterium tumefaciens and regeneration from hypocotyl explants

Summary Transgenic cucumber (Cucumis sativus L.) plants were successfully obtained from hypocotyl explants inoculated with Agrobacterium tumefaciens, which harbored a binary vector plasmid with NOS-nptII, CaMV 35S-I-gus and CaMV 35S-hph genes. Acetosyringone enhanced the efficiency of transformation at the cut surface cells of hypocotyl explants during five days of co-cultivation. Transformed cells were more effectively selected using 20–30 mg/l hygromycin B than using 50–100 mg/l kanamycin. Shoot regeneration occurred within 4–6 wks, and 12 of 21 regenerated plantlets displayed strong GUS expression in the very young leaves. All of 8 GUS-positive R0 plants examined showed single or a few positive bands by Southern blot analysis. The expression of the CaMV 35S-I-gus gene was observed in various tissues and organs of R0 and R1 transgenic cucumber plants.     

Effects of 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS) on carnation flower longevity

The effects of a novel preservative for cut carnation flowers, 1,1-dimethyl-4-(phenylsulfonyl)semicarbazide (DPSS), were investigated. DPSS extended the vase life of cut carnation flowers not only by continuous treatment but pulse treatment as well. This inhibition of senescence by DPSS appeared to depend on that of ethylene production in carnation flowers. DPSS provided no protection from the action of ethylene nor did it inhibit 1-aminocyclopropane-1-carboxylic acid (ACC) synthase. It did inhibit ACC-dependent ethylene production in carnation petal discs, suggesting possible potential for inhibiting ACC oxidase.     

BTKbase, mutation database for X-linked agammaglobulinemia (XLA).

X-linked agammaglobulinemia (XLA) is an immunodeficiency caused by mutations in the gene coding for Bruton's agammaglobulinemia tyrosine kinase (BTK). A database (BTKbase) of BTK mutations has been compiled and the recent update lists 225 entries from 189 unrelated families showing 148 unique molecular events. Each patient is given a unique patient identity number (PIN). Information is included regarding the phenotype including symptoms. Mutations in all the five domains of BTK have been noticed to cause the disease, the most common event being missense mutations. The mutations appear almost uniformly throughout the molecule and frequently affect CpG sites forming arginine residues. A decreased frequency of missense mutations was found in the TH, SH3 and upper lobe of the kinase domain. The putative structural implications of all the missense mutations are given in the database.     

Organic-Solvent-Tolerant Bacterium Which Secretes Organic-Solvent-Stable Lipolytic Enzyme

A bacterial strain which could be grown in a medium containing organic solvents and which could secrete lipolytic enzyme was isolated. The stability of the lipolytic activity of the supernatant of the culture increased significantly in the presence of organic solvents such as toluene, cyclohexane, ethanol, and acetone.