A sample of [

3H

] tobrarnycin (

5

, 000 Ci/Mole) has been synthetized and incubated with
the bacterial ribosome and its subunits. The results obtained show that this antibiotic has
two types of binding sites. The primary one is probably responsible for the inhibition of
protein synthesis whereas the secondary one is probably related to the misreading and reading
tiirough of the messenger RNA.

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(

3H

) Tobramycin was used as a probe to determine the relationship between the structure of aminoglycoside antibiotics and their ability to remove this drug from its higher affinity binding site on the ribosome. The dissacharide moieties (neamine, tobramine, gentamine) appeared to have a common binding site, whereas the kanosamine, garosamine and ribose moieties determined the specificity of this binding. Amikacin and butikacin behaved in an anomalous manner in spite of their close structural relationship to tobramycin.

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The activities of tobramycin derivatives acetylated and ethylated on the '-N, 2'-N and -N positions were examined. The MICs of these derivatives against tobramycin sensitive strains indicated that 2'-N-ethylated and '-N-ethylated derivatives have a fairly good activity, and confirmed that the -N position is the most important one for antibiotic activity since -N derivatives were less active. The MICs of these derivatives against tobramycin resistant strains, and their inactivation by tobramycin modifying enzymes were examined. These results showed that 2'-N or '-N ethylation protects the drug against inactivation by AAC(2') or AAC('), respectively, and 2'-N-ethyltobramycin and '-N-ethyltobramycin were active against strains containing these modifying enzymes. On the other hand, -N ethylation protects the drug against inactivation by AAC() but -N-ethyl tobramycin does not inhibit strains containing this enzyme.

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Nine isoquinoline alkaloids belonging to the protoberberine, proaporphine and bisbenzyl-isoquinoline series were isolated from Caryomene olivascens (Menispermaceae). Four compounds are new : (-)-2-norlimacine (), (-)-caryolivine (), (+)-1, 2-dehydro-2-norlimacusine () and N-formylstepharine (). The last one is the first N-formyl derivative to be reported in the proaporphine group. Its biogenetic origin is discussed. Structures were established on the basis of 360 MHz (FT) nuclear magnetic resonance measurements and also by chemical correlation in the case of .

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Circuit techniques to enhance the linearity of input-voltage-to-current (V/I) conversion and to increase the output impedance of a current source by compensating for the low intrinsic gain of a transistor were introduced to realize a high-frequency operational transconductance amplifier (OTA) for a low supply voltage using sub-100-nm CMOS processes. Applying these techniques, a MOS 7th-order Gm- linear-phase low-pass filter (LPF) was realized using a 65nm CMOS process. A simplified biquad LPF that can serve as a component of a 7th-order LPF was newly developed by replacing OTAs with resistors. As a result, the -dB frequency bandwidth, group delay ripple, rd-order distortion, and rd-order input intercept point (IIP) were 200MHz, 2.2%, ≤ -55dB with a 100MHz input, and +10.dBm, respectively, all with a ±0.1Vp-p input signal at each input terminal in the pseudodifferential configuration. The LPF including an output buffer dissipated 60mW in the case of a 1.2V supply. Wide spurious-free dynamic range (SFDR) characteristics were confirmed up to high frequencies.

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Since 135 years .H.Will Hamburg is one of the leading manufacturers of converting machinery for the paper industry.The company has gained worldwide acknowledgement when introducing cut size sheeters for copy paper. These machines are used worldwide by all well-known paper makers and also in the meantime by smaller paper converting companies.
With regard to folio size sheeter .H.Will was and is reknown for special solutions instead. Based on and with the knowhow of hundreds of cut size sheeters and some hundred folio size sheeters having been delivered, the concept of the Will “global folio size sheeter” type GFS has been developed.
The great technical experience in cutting and transporting paper as well as introducing innovative ideas, new materials and, last but not least, the influence of various customers' requests, which are known to .H.Will from numerous special projects, were the base for development of the GFS folio sheeter.

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Pironetin 1 (PA-48153) is a novel unsaturated δ-lactone derivative isolated from the fermentation broths of Streptomyces species which shows immunosuppressive and plant growth regulating activities. Several total syntheses of 1 have been reported to date, but we show here a novel approach to 1 via a convergent route using our chiral building block, (1S,S,R)--hydroxybicyclo[.1.0]heptan-2-one . We dissected pironetin at -7 and employed the coupling of the epoxide 16 with the dithiane 25, which would be derived from , as a key step. The THP ether of was methylated and the following reduction gave an inseparable mixture of four diastereomers . After etherification, removal of THP group afforded separable isomers a and in a ratio of 13 to 1. The desired major isomer a was oxidized to ketone . Oxidation of via silyl enol ether with osmium tetroxide gave ketol 21 in quantitative yield. Reduction of cyclopropylketone moiety of 21 under Birch condition afforded a mixture of a and . The ketol moiety of a and was oxidatively cleaved with lead tetraacetate in benzene-methanol to give the single aldo-ester 23. Acetalization of 23 followed by reduction of ester group gave aldehyde 24. Introduction of 2-unit via Takai's protocol as -olefin formation followed by thioacetalization afforded the dithiane 25, as 7-14 unit of pironetin. Meanwhile, the epoxide 16 as 1- unit was prepared from known epoxy alcohol in steps. Coupling reaction of two units, the dithiane 25 and the the epoxide 16, successfully gave the product with the whole skeleton 26 in high yield. Mercuric ion assisted hydrolysis of the thioacetal 26 gave ketol 27. Selective reduction of β-hydroxyketone 27 by Mori's method afforded and-diol 28a predominantly (: ). Finally, desilylation and oxidation with manganese dioxide afforded pironetin 1.

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A review of the actinide and lanthanide extraction chemistry by N, N-dialkylamides and N, N'- tetraalkylamides is given. It includes the extraction equilibria of inorganic acids. The prospects of using. these completely incinerable extractants in the nuclear fuels cycle is discussed.

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Leakage of water due to internal erosion through a dam body or foundation is a major problem with fill-type dams. Recent case histories and research suggest that most cases of internal erosion are possibly triggered by hydraulic fracturing. However, the quantitative mechanism of hydraulic fracturing still remains to be solved. Therefore in-situ hydraulic fracture tests were carried out with a cheap, concise apparatus using boreholes dug in the soft clayey volcanic soil foundation of a low earth dam (Oyachi Dam) in Niigata Prefecture. Water was injected into the foundation through a perforated pipe by two methods : one was under a controlled injection pressure and the other was a controlled injection flow rate. In the former method, the relationship between flow rate and injection pressure was observed and it was found that a yield pressure or fracture pressure existed in all the tests. By repeating the injection test it was confirmed that once a crack is developed, it is very easily reopened by a water pressure a little higher than the earth pressure exerted on the crack. In the latter method, the relationship between injection pressure and time was observed and it was found that fracture pressure varied with flow rate. The boreholes were excavated to observe the development of fracture cracks and it was also found that the cracks had developed perpendicular to the borehole periphery, which means that fracture cracks were induced by tensile stress and denies the explanation that fractures are caused by shear failure.

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We compared three groups of pregnant women: placebo with normotensive women, group A which included preeclamptics, and group which comprised preeclamptics who were supplemented their diets with vitamins and . MDA increased from . ± 2. (placebo) to .48 ± 1.2 (A) and .02 ± 1. nmol/gHb (). NO concentrations were enhanced from 19. ± .2 (P) to 23. ± . (A) and 24.1 ± . μmol/L (). GSH contents were decreased from 10.42 ± 2.81 (P) to .02 ± 2.92 (A) and .39 ± 1.02 μmol/g Hb (), whereas GSSG concentrations increased from 0.98 ± 0.28 (P) to 1.24 ± 0.29 (A) and 1.08 ± 0.12 μmol/g Hb (). SOD activity decreased 23% in A and 14% in ; GRx decreased 27% in A and .% in ; GPx decreased 12% in A and .% in . Catalase activity, however, increased 27% in A and 29% in as compared to control. Thus, we conclude that the use of vitamins and should be considered for the control of certain important biochemical indices during the development of preeclampsia; however, further studies are needed to develop methods for the prevention of preeclampsia in women at high risk.

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