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Pheromonal and kairomonal activities can be separated: synthesis and bioactivity studies of pine bast scale sex pheromones and their analogues.

New syntheses were achieved to secure matsuone (1), the pheromone of the pine scale Matsucoccus matsumurae, that of M. feytaudi (2), and that of M. josephi (3). Five analogues (4-8) of 1, 2, and 3 were synthesized and their bioactivities studied. The pheromone analogue 7 showed relatively strong pheromonal activity toward M. josephi, while it was inactive as a kairomone toward the predator Elatophilus hebraicus. Similarly, analogue 8 acted as a pheromone for M. feytaudi, but it did not attract any of its local predators. The M. feytaudi pheromone 2 exhibited strong kairomonal activity toward E. hebraicus, but was not active as a pheromone mimic to attract M. josephi.

Animals↗

Bioactivation of 7-hydroxymethyl-12-methylbenz[a]anthracene by rat liver bile acid sulfotransferase I.

The bioactivation of 7-hydroxymethyl-12-methylbenz[a]anthracene (HMBA) to an electrophilic sulfuric acid ester metabolite has been shown to be catalyzed by rat liver bile acid sulfotransferase I (BAST I). The sulfation and activation of HMBA by BAST I was determined by the ability of sulfated HMBA to form DNA adducts. The BAST I was also shown to react with rabbit anti-human dehydroepiandrosterone sulfotransferase antisera and to represent a major form of hydroxysteroid/bile acid sulfotransferase in female rat liver cytosol. Higher levels of BAST I activity and immunoreactivity as well as HMBA-DNA adduct formation were detected in female rat liver cytosol than in male rat liver cytosol. The bioactivation of HMBA by pure BAST I was dependent on the presence of 3'-phosphoadenosine 5'-phosphosulfate (PAPS) in the reaction and was inhibited by dehydroepiandrosterone, a physiological substrate for BAST I. Glutathione, a cellular nucleophile with important protective properties, decreased DNA adduct formation in the HMBA sulfation reaction in the absence of glutathione S-transferase activity. These results indicate the usefulness of BAST I to investigate the sulfation and activation of HMBA and probably other hydroxymethylated polyaromatic hydrocarbons to electrophilic and mutagenic metabolites under defined reaction conditions.

9,10-Dimethyl-1,2-benzanthracene↗

Difference in enzymatic sulfation of bile acids between the mouse and rat.

Species difference in bile acid-sulfotransferase (BAST) activity was studied between the mouse and rat. Cytosol fractions of the liver, kidney, small intestine and large intestine were incubated with bile acids and 3' phosphoadenosine-5'-phosphosulfate. The mouse liver showed BAST activity for lithocholic acid, taurolithocholic acid and taurochenodeoxycholic acid, whereas the rat liver and kidney had the activity for taurodeoxycholic acid in addition to these compounds. The highest activities were found in the mouse liver and rat kidney. The mouse small intestine showed weak activity only for lithocholic acid. No activity was found in other organs. BAST was inactive towards taurocholic acid, 7 alpha- or 12-monohydroxy-5 beta-cholanoic acid. Optimal pH of liver BAST in the two species was different from that of the rat kidney. BAST of the mouse liver showed the highest activity without addition of Mg2+, whereas that of the rat liver and kidney showed enhancement by exogenous Mg2+. These results indicated that the distribution and characteristics of mouse BAST was different from rat BAST. Such difference should be reminded in any animal study involving the two species.

Animals↗

Bile acid sulfotransferase I from rat liver sulfates bile acids and 3-hydroxy steroids: purification, N-terminal amino acid sequence, and kinetic properties.

A bile acid:3'phosphoadenosine-5'phosphosulfate:sulfotransferase (BAST I) from adult female rat liver cytosol has been purified 157-fold by a two-step isolation procedure. The N-terminal amino acid sequence of the 30,000 subunit has been determined for the first 35 residues. The Vmax of purified BAST I is 18.7 nmol/min per mg protein with N-(3-hydroxy-5 beta-cholanoyl)glycine (glycolithocholic acid) as substrate, comparable to that of the corresponding purified human BAST (Chen, L-J., and I. H. Segel, 1985. Arch. Biochem. Biophys. 241: 371-379). BAST I activity has a broad pH optimum from 5.5-7.5. Although maximum activity occurs with 5 mM MgCl2, Mg2+ is not essential for BAST I activity. The greatest sulfotransferase activity and the highest substrate affinity is observed with bile acids or steroids that have a steroid nucleus containing a 3 beta-hydroxy group and a 5-6 double bond or a trans A-B ring junction. These substrates have normal hyperbolic initial velocity curves with substrate inhibition occurring above 5 microM. Of the saturated 5 beta-bile acids, those with a single 3-hydroxy group are the most active. The addition of a second hydroxy group at the 6- or 7-position eliminates more than 99% of the activity. In contrast, 3 alpha,12 alpha-dihydroxy-5 beta-cholan-24-oic acid (deoxycholic acid) is an excellent substrate. The initial velocity curves for glycolithocholic and deoxycholic acid conjugates are sigmoidal rather than hyperbolic, suggestive of an allosteric effect. Maximum activity is observed at 80 microM for glycolithocholic acid. All substrates, bile acids and steroids, are inhibited by the 5 beta-bile acid, 3-keto-5 beta-cholanoic acid. The data suggest that BAST I is the same protein as hydrosteroid sulfotransferase 2 (Marcus, C. J., et al. 1980. Anal. Biochem. 107: 296-304).

Amino Acid Sequence↗

Z-100, a lipid-arabinomannan extracted from Mycobacterium tuberculosis, improves the resistance of thermally injured mice to herpes virus infections.

The effect of Z-100, a lipid-arabinomannan extracted from Mycobacterium tuberculosis strain Aoyama B, was investigated on the resistance of thermally injured mice (TI-mice) to herpes simplex virus type 1 (HSV) infections. The susceptibility of TI mice to infection was about 100 times greater than it was in normal mice (N mice). However, the increased susceptibility of TI mice to infection was effectively counteracted to the levels observed in N mice when treated with Z-100 (10 mg/kg i.p.; 1, 3 and 5 days after thermal injury). Adoptive transfer of burn-associated CD8+ CD11b+ TCR gamma/delta + suppressor T (BAST) cells, prepared from TI mice, increased the susceptibility of N mice to infection by HSV, while the susceptibility of N mice, inoculated with the CD8+ T-cell fraction prepared from Z-100-treated TI mice (ZTC), to infection was not changed. In addition, the suppressor cell activity of BAST cells was not demonstrated when they were assayed in vitro in the presence of anti-IL-4 monoclonal antibody (mAb). BAST cells released IL-4 into their culture fluids without stimulation. The suppressor cell activity of ZTC and IL-4 production by ZTC were minimal. These results suggest that Z-100 may improve the resistance of TI mice to HSV infection through the regulation of BAST cells and/or the release of IL-4 from these cells.

Adjuvants, Immunologic↗

A simplified technique for airway correction at the nasal valve area.

OBJECTIVE: To describe a simplified system to correct an obstructed nasal airway utilizing the Mitek bone anchor suspension technique (BAST). STUDY DESIGN: This is a retrospective/prospective study of patients with nasal airway obstruction treated with the BAST. The retrospective study is based on 188 patients who underwent the BAST over the past 5 years and were analyzed to assess complications and subjective results. The prospective group consisted of 52 patients with unilateral or bilateral valve obstruction who were assessed with preoperative and postoperative rhinomanometry and quality of life (QOL) questionnaires. METHODS: The surgical technique is based on introducing a bone anchor into the orbital rim through a 4-mm stab incision. The bone anchor system comes with attached sutures that are easily passed to the valve area and secured in position to support and open the valve area. Preoperative and postoperative QOL surveys and rhinometric studies were compared in 52 patients to assess the subjective and objective outcomes of the procedure. RESULTS: Based on subjective data, over 90% of the patients had significant improvement in their nasal airway. Objectively, cross-sectional areas at the nasal valve were found to have significantly improved postoperatively (P < 0.046). Complications were rare and limited to localized infection, reaction to sutures, and loss of support. CONCLUSION: Correction of nasal valve obstruction with this technique provides a simplified alternative in selected patients to improve airflow and decrease nasal resistance. The BAST allows for a simple, highly effective correction of an obstructed airway with minimal complications.

Airway Resistance↗

Leukemia serum reactive with retrovirus-related antigen in normal human placenta.

Serum antibody reactive with a retrovirus-related p30 antigen in human normal term placenta was investigated and characterized by immunohistologic and immunoblotting methods. Sera obtained from patients with acute leukemia and malignant lymphoma were used as first antibody, and cryostat sections of placenta were the target antigen. An IgM antibody that reacted mainly with the basal aspect of syncytiotrophoblast of chorionic villi, where a putative human endogenous retrovirus p30 antigen is located, was directed by indirect immunofluorescence. This antibody activity, termed anti-basal aspect of syncytiotrophoblast (anti-BAST), was detected in the sera of many patients with acute leukemia (AML, ALL) and malignant lymphoma, and less frequently in sera of pregnant women and normal controls. As shown by immunoblotting analysis, the main reactive antigen recognized by anti-BAST was a non-glycosylated 32-kDa placental protein which was antigenically related to SSAV p30. A non-glycosylated 19-kDa protein was also considered to be one of the anti-BAST-corresponding antigens. This suggests the presence of a new antigen-antibody system of human retrovirus(es) revealed by subinfectious antigenic expression and by specific antibody activity in conditions of human health and disease, particularly, acute leukemias and malignant lymphomas of common types.

Antibody Specificity↗

Technologically indicative properties of straw fractions of flax, linseed (Linum usitatissimum L.) and fibre hemp (Cannabis sativa L.).

In this study of the behaviour of the fractions of unretted and frost-retted fibre straws in damp air, a production scale method to separate fibre and shive from fibre plants was introduced and tested on bast fibre plants (Linum usitatissimum L. and Cannabis sativa L.). The method consists of optional drying of stalks, unloading bales, milling the straws with a hammer mill, separating the fractions from air stream with a cyclone and finally separating fibres from shives with a screening drum. Fractions were characterized focusing on technologically indicative properties such as equilibrium moisture content, ash and microbiological quality. Unretted fractions of the bast fibre plant stem reached higher equilibrium moisture contents than the retted fractions, and hemp fibres absorbed more moisture from air than did the Linum fibres. In very humid air, all fractions began to lose weight due to moulding. The weight decrease during the first week was lower in frost-retted than in unretted fractions. The frost-retted fractions appeared to be more resistant to humidity in the short term. The total number of microbes and especially the numbers of yeasts and moulds can be used as a criterion of hygienic level. For green fractions, the mould level was similar in fibres and in shives, but frost-retted shives contained more moulds than the unretted shives. The mould content of a fraction had no direct correlation with the moulding tendency of the fraction. The ash contents of fibres were somewhat higher than those of shives, due to a probable soil contamination. Ash content did not have significant correlation with microbiological quality, although ash is a possible risk factor for hygienic quality. According to the results of this study it is highly important to study the quality of the production chain of bast fibre plants to ensure the quality of industrial products. From the producer's point of view, raw material with defined quality can be directed to the most suitable application. The behaviour of fractions in various ambient atmospheres, and other quality aspects such as hygienic level can be used as criteria for defining the most appropriate product applications.

Bacteria↗

Tie-over bolster dressings may not be necessary to secure small full thickness skin grafts.

BACKGROUND: The accepted method for securing full thickness skin grafts (FTSG) is with a tie-over bolster dressing, with or without basting sutures. We question the need for tie-over bolster dressings for small FTSGs. OBJECTIVE: We describe our method of FTSG reconstruction and the outcome in a consecutive series. METHODS: Thirty patients with surgical defects following tumour excision from the face24, scalp1, ear2, and finger3 ranging in diameter from 8 to 45 mm (mean 20 mm) were reconstructed with a FTSG. Interrupted monofilament nylon perimeter sutures only were used, with antibiotic ointment at the wound edge with either a light dressing or no dressing. RESULTS: A series of 30 FTSG secured without a tie-over bolster dressing or basting sutures is described, all with good to excellent long term results. In two cases there was early superficial necrosis of the graft, but ultimately 100% graft take. CONCLUSION: We have found tie-over bolster dressings and basting sutures to be unnecessary in our series of small FTSG. This technique saves time and material and minimizes handling of the graft.

Adult↗

Effect of streptozotocin-induced diabetes on bile acid sulfation in male rat liver.

The sulfation of bile acids is hormone dependent, being increased in females and ethynylestradiol (EE)-treated males compared with normal males. Diabetes causes significant alterations in estrogen metabolism and uterine estrogen receptor kinetics. Male rats were given streptozotocin (90 mg/kg) and diabetes was verified. An increase in hepatic bile acid sulfotransferase (BAST) activity was significant by 6 days and continued to increase to 29 days. This increase was prevented by insulin replacement. Administration of EE (6.0-600 micrograms X kg-1 X day-1) to normal male rats resulted in a significant increase in hepatic BAST activity; however, administration of similar doses of EE to diabetic males failed to further increase activity levels over the already-elevated levels in the diabetic controls. This increase in in vitro specific activity was accompanied by an increase in the biliary excretion of lithocholate 3-sulfate and taurolithocholate 3-sulfate in 21-day-diabetic animals. Bile flow and total bile acid excretion were also markedly increased in the diabetic animals. The data indicate that streptozotocin-induced diabetes causes a significant increase in hepatic BAST activity. These findings are consistent with an alteration in hepatic estrogen action in streptozotocin-induced diabetes.

Animals↗

Lipids from flax fibers and their fate in alkaline pulping.

The chemical composition of lipids from bast fibers of flax (Linum usitatissimum), which are commonly used for high-quality paper pulp production, was thoroughly studied by gas chromatography-mass spectrometry. The main compounds identified were waxes, series of long chain n-fatty alcohols, n-aldehydes, n-fatty acids, and n-alkanes. Free and esterified sterols and triterpenols, steroid hydrocarbons, steroid and triterpenoid ketones, as well as sterol glycosides were also found in the flax bast fibers. On the other hand, the fate of these lipophilic compounds in alkaline pulping of flax fibers was investigated by analyzing two pulps obtained under distinct industrial cooking conditions. The results revealed that while waxes could be efficiently hydrolyzed during pulping depending on the alkali charge, most of the other lipophilic compounds present in flax fibers survived cooking and were present in the unbleached pulps.

Alcohols↗