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[Determination of hydrogenated terphenyls by ultraviolet spectrophotometer in the air of work place].

OBJECTIVE: To determine Hydrogenated terphenyls in the air of work place. METHODS: Hydrogenated terphenyls in the air was collected with 40% alcohol solution and determined by ultraviolet spectrophotometer. RESULTS: The detectable limit was 0.87mg/m3. When the concentration of standard solution was 0 - 20mg/L, the relative standard deviation (RSD) was 4.6% - 2.3%. The sampling efficiency was 97.3%. The samples were stable for 7 days. CONCLUSION: It was proved that the method was fast, simple and accurate. It was suitable for the determination of hydrogenated terphenyls in the air of work place.

Air Pollutants, Occupational↗

Studies on the effect of quartz, bentonite and coal dust mixtures on macrophages in vitro.

The effect of quartz, bentonite and coal dusts as well as the effect of the artificial mixture of these dusts on TTC reduction and extra-and intra-cellular lactate dehydrogenase activity in peritoneal rat macrophages was determined in vitro. The cell-membrane-damaging effect of quartz caused a significant extracellular release of lactate dehydrogenase. Bentonite caused no extracellular enzyme release, which leads us to believe that the biological effect of this dust is shown by decrease in intra-cellular lactate dehydrogenase activity. TTC reduction was inhibited equally by quartz and qentonite. In mixtures of quartz (60%)-bentonite (40%) dust the specific effect of quartz was inhibited by bentonite in vitro and also in vivo. We obtained the same results with coal-quartz-bentonite dust mixtures in vitro. Our experiments show that comparison of the biological effects of artificial dust mixtures and airborne dust samples is justified, and prove that performing various examinations simultaneously give fuller particulars on the probable biological effect of mineral dusts.

Animals↗

[Tercuronium, a new nondepolarizing myorelaxant with high activity and selective action].

Tercuronium is p',p"-bis-triethylammonium-p-terphenyl dibenzosulfonate. As a curarelike agent tercuronium is 4--8 times as potent as (+)-tubocurarine. The time of the development and lasting of the blocking effect of tercuronium is approximately the same as that of (+)-tubocurarine. In a blocking dose tercuronium does not exert any effect either on the vegetative ganglia or arterial blood pressure. Partial blocking of the transmission through the vegetative ganglia as well as an insignificant and short-term drop of arterial blood pressure are recorded after intravenous injection of 10 myoparalytic doses of tercuronium. The antagonism of neostigmine against tercuronium was more pronounced than against (+)-tubocurarine, pancuronium and gallamine.

Animals↗

[Results of using an accelerated method of determining microbial flora sensitivity to antibacterial preparations in the surgical clinic].

Express diagnosis using 2,3,5-triphenyltetrasolium chloride as the redox indicator provided in most tests rapid and sufficiently precise determination of the microbial flora sensitivity to antibacterial drugs permitting to start in time the antibiotic therapy of the patients. For rapid response it proved to be useful to incubate beforehand the test material taken from surgical patients within 16 to 18 hours and to increase the indicator concentration up to 2--3 per cent.

Anti-Bacterial Agents↗

Modification and inheritance of pleiotropic cross resistance and collateral sensitivity in Saccharomyces cerevisiae.

A meiotic segregant (oliPR1) was isolated with a phenotype of multiple cross resistance and collateral sensitivity. Strain oliPR1 has increased sensitivity to ethidium bromide, dequalinium chloride, acriflavin, paromomycin and neomycin, and increased resistance to oligomycin, rutamycin, venturicidin, triethyltin bromide, antimycin, carbonylcynamide-m-chlorophenylhydrazone, tetra-N-butylammonium bromide, dibenzyldimethylammonium chloride, triphenylmethlphosphonium bromide, chloramphenicol, carbomycin, tetracycline, triton X-165 and cycloheximide. Single gene inheritance of the cross resistance and collateral sensitivity was shown by 2:2 parental ditype segregation and reversion of the complete phenotype by a spontaneous revertant. The locus conferring the oliPR1 phenotype was mapped 11.7 units from an unspecified centromere. Antibiotic resistance showed incomplete dominance, with the level of hybrid resistance dependent upon the inhibitor tested. Resistant diploids that produced four resistant ascospores were the result of mitotic recombination prior to meiosis. A partial revertant phenotype (sensitive to all inhibitors except oligomycin, antimycin and carbonylcyanide-m-chlorophenylhydrazone) was shown to be due to a single nuclear gene causing partial suppression of oliPR1. Anaerobic pretreatment, 37degrees and 0.5 MKC1 were observed to reduce the growth of oliPR1 when challenged with seven diverse inhibitors (antimycin, carbonylcyanide-m-chlorophenylhydrazone,-chloramphenicol, cycloheximide, oligomycin, triethyltin bromide, and triphenylmethylphosphonium bromide). Resistance to cycloheximide was not altered by the [rho--] state. A revertant of oliPR1 (sensitive to the above inhibitors but resistant to ethidium bromide, paromycin and neomycin) showed anaerobic and temperature sensitization to ethidium bromide, paromomycin and neomycin. Continuous monitoring of oxygen uptake by the revertant afteranaerobic pretreatment revealed that anaerbiosis sensitized respiratory adaptation of the revertant to neomycin. It is proposed that oliPR1 is a mutation resulting in the alteration of plasma membrane permeability to many diverse inhibitors.

Antimycin A↗

An evaluation of chromatographic methods for the analysis of polychlorinated terphenyls in environmental samples.

Gas chromatography (GC) with packed and capillary columns, high-performance liquid chromatography (HPLC) and thin-layer chromatography have been used to characterize various commercially available mixtures of polychlorinated terphenyls (PCTs). Besides, UV absorption and mass spectrometry data have been collected, and the behaviour of PCTs upon perchlorination to the tetradecachloroterphenyls has been studied. Using GC, the PCT content of a number of paper and sewage sludge samples has been determined. The application of perchlorination/GC as method of analysis often yields unreliable, i.e., too high, results compared with the direct GC pattern-comparison method. In the case of paper samples, hydrogenated terphenyls appear to be the principal interfering compounds.

Chromatography, Gas↗

A photophysical study of terphenyl core oligosulfonimide dendrimers exhibiting high steady-state anisotropy.

The photophysical properties of three dendrimers containing a p-terphenyl core with appended sulfonimide branches of different size and n-octyl chains have been investigated in dichloromethane solution. In the dendrimer absorption spectra contributions from both the branches and the core are clearly identified. The fluorescence spectra show only the characteristic fluorescence of the terphenyl unit. Energy transfer from the appended chromophoric groups to the core does not occur. In the dendrimers, the terphenyl core exhibits a very high fluorescence quantum yield (ca. 0.75) and a short emission lifetime (0.8 ns). These properties allowed investigations of the fluorescence depolarization caused by rotation of the dendrimers. The dendrimers show a very high steady-state anisotropy in dichloromethane solution at room temperature (0.24 for the largest one), compared to that of the parent terphenyl under the same experimental conditions (<0.01) and in rigid matrix (0.33). Both the n-octyl chains and the sulfonimide branches play important roles to slow down the molecular rotation.

Anisotropy↗

Antithrombotic effects of the novel inhibitor of thrombin-induced offtelet aggregation and thrombus formation, 3-[2-[1,1':2',1"]-terphenyl-4'-yl)ethyl]phenoxyacetic acid.

The new compound 3-[2-([1,1':2,1"]-terphenyl-4'yl)ethyl]phenoxyacetic acid (F1070) was synthesized and its effects on platelet aggregation induced by thrombin, thrombin receptor agonist peptide (TRAP), ADP and collagen were evaluated in humans, guinea pigs and rats, and were compared with the effects of he thrombin antagonists argipidine and (D)Phe-Pro-Arg-CH2Cl (FPR). F1070 inhibited the platelet aggregation induced by these agonists and was highly selective in its inhibition of thrombin. F1070 inhibited fibrin formation induced by thrombin, but far less effectively than argipidine. In a guinea pig model of extracorporeal circulation thrombosis, F1070 (10 mg/kg p.o.) significantly inhibited the development of a thrombus. F1070 is thus a key compound that should facilitate the development of new orally active antithrombotic drugs that are specific for thrombin.

Animals↗

Polychlorinated terphenyls as an environmental pollutant in Japan.

This paper summarizes the results of the studies made by our group and other investigators in Japan on the residue levels of polychlorinated terphenyls (PCTs) in a variety of items in the environment including the human body. In contrast to widespread distribution of PCBs in the environment, PCT residues were seldom found in samples from aquatic environments such as water and sludge and waterfowl and fish, and, if found, the levels of PCTs were so low as to be practically negligible. Similarly, no significant levels of PCTs were detectable in foodstuffs such as edible oils, vegetables, dairy products and meat and in prepared diets. These findings may be explained by the fact that PCTs are much less volatile and soluble than PCBs and the total industrial output of PCTs was as small as 2700 tonnes which is 1/20 of PCBs produced in Japan. However, the levels of PCTs in human fat and blood were shown to be almost equivalent to PCBs, despite a negligible amount of PCTs being found in food. No clear explanation of human contamination by PCTs has been proposed so far.

Adipose Tissue↗

Effects of polychlorinated biphenyls and terphenyls and polybrominated biphenyls on pentobarbital sleeping times of Japanese quail.

Polychlorinated biphenyls (Aroclor 1221, 1232, 1242, 1248, 1254, 1260, 1262, and 1268), polychlorinated terphenyls (Aroclor 5460), a mixture of polychlorinated biphenyls and terphenyls (Aroclor 4465) and polybrominated biphenyls (BP-6) were administered in a single dose, 100 mg/kg body weight injected orally, to mature male and female Japanese quail. Two hr after Aroclor treatment, pentobarbital sleeping times were prolonged (2 to 3 times control) in both male and female quail. Twenty-four hr after treatment, sleeping times were similar to those of controls. However, 48 hr after treatment with Aroclor 1248 through Arolcor 5460 and with BP-6, sleeping times of males were only 1/2 those of controls, whereas after treatment with Aroclor 1221, 1232 and 1242, sleeping times were similar to those of controls. The reduction in sleeping times of male quail 48 hr after administration of PCBs was correlated with the percentage of chlorine in the PCB with greater reductions in male than female quail. The response after three days ad libitum feeding of 300 ppm of each substance was the same as the response 48 hr after a single oral injection. Although very few birds died from the toxicity of the Aroclors and BP-6, mortality was greatly increased during anesthesia when the pentobarbital was administered two hr after single oral dosing.

Animals↗