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Zusammenfassung. Die Symptomatologie der malignen Rhinopharynxtumores wird auf Grundlage ihrer topographischen Anatomie, Wachsart und lymphatischen Ausbreitung dargestellt. Die vage und uncharakteristische von der Kleinheit des Primartumors bedingte Art der Initialsymptome wird hervorgehoben, die lymphatischen Halsdrusen-metastasen sind fruhzeitig. Die enge Beziehung des Tumors zur Basis cranii und seine Neigung in dieselbe hinein zu wachsen verursachen Craniennerven-Lasionen, insbesondere der Augennerven. Aus der Radiumstation, Kopenhagen, wo 1931-40 im ganzen 64 Patienten mit malignen Rhinopharynx-Tumoren behandelt wurden, wird uber 20 dieser Falle berichtet, welche ophtalmologische Symptome aufwiesen, und zwar am haufigsten Abducensparese, am seltensten Opticuslasion. Bei den betreffenden 20 Patienten wurden im ganzen 50 Augennervenlasionen constatiert. Verlauf und Behandlung werden besprochen. Die Bedeutung einer fruhzeitigen Diagnose wird hervorgehoben, weil sich namlich durch moderne Strahlenbehandlung das Leiden beseitigen lasst.

A new nitrile hydratase producing strain of Rhodococcus has been found. A method for purification of the nitrile hydratase and a characterization of the enzyme is described. The hydratase is a 52-kdal protein consisting of two subunits of molecular weights, 26 and 23 kdal, respectively. The hydratase exhibits a broad substrate specificity. Aliphatic saturated or unsaturated nitriles, as well as aromatic nitriles, are substrates for the enzyme. Inhibition of the enzyme activity by amides and carboxylic acids was observed. The optimum pH of the hydratase is 7.5. The enzyme is rather unstable, even at room temperature. The enzyme may be applied for the production of acrylamide. For this application of the enzyme, the optimal temperature is about 4°C, where the enzyme exhibits a satisfactory activity and stability.

OBJECTIVES: The purpose of the present study was to evaluate skeletal stability after mandibular advancement with bilateral sagittal split osteotomy.MATERIAL AND METHODS: Twenty-six patients underwent single-jaw bilateral sagittal split osteotomy (BSSO) to correct skeletal Class II malocclusion. One group (n = 13) were treated postoperatively with skeletal elastic intermaxillary fixation (IMF) while the other group (n = 13) where threated without skeletal elastic IMF.RESULTS: The mean advancement at B-point and Pog in the skeletal elastic IMF group was 6.44 mm and 7.22 mm, respectively. Relapse at follow-up at B-point was -0.74 mm and -0.29 mm at Pog. The mean advancement at B-point and Pog in the no skeletal elastic IMF group was 6.30 mm and 6.45 mm, respectively. Relapse at follow-up at B-point was -0.97 mm and -0.86 mm at Pog. There was no statistical significant (P > 0.05) difference between the skeletal IMF group and the no skeletal group regarding advancement nor relapse at B-point or Pog.CONCLUSIONS: Bilateral sagittal split osteotomy is characterized as a stable treatment to correct Class II malocclusion. This study demonstrated no difference of relapse between the skeletal intermaxillary fixation group and the no skeletal intermaxillary fixation group. Because of selection-bias and the reduced number of patients it still remains inconclusive whether to recommend skeletal intermaxillary fixation or not in the prevention of relapse after mandibular advancement.

Monoclonal antibodies catalyzing lysis of 4-nitrophenyl esters have been created using a phosphonate as hapten in the immunization. Among 960 hybridomas screened, 3 were found to produce antibodies catalyzing hydrolysis of 4-nitrophenyl butanoate (1). Two of the antibodies accelerate the reaction by factors of 1.3 × 104 and 1.1 × 104, respectively, while the third antibody is significantly less effective. The two catalytically most effective antibodies also catalyze perhydrolysis of 1, i.e., lysis with hydrogen peroxide, to generate peroxybutanoic acid. Perhydrolysis was found to be the predominant reaction even in dilute solutions of hydrogen peroxide. Both antibodies also catalyze hydrolysis of both 4-nitrophenyl hexanoate and decanoate, but do not catalyze hydrolysis of 4-nitrophenyl acetate. The antibodies are more selective with respect to the aromatic part of the substrate as they do not catalyze hydrolysis of 2-nitrophenyl butanoate or 4-sulfophenyl nonanoate. Furthermore, neither of the antibodies...

The ability of hydrolases to catalyze perhydrolysis, i.e. lysis of acyl substrates with hydrogen peroxide to form peroxycarboxylic acids, has been investigated. Lipases, esterases and cholinesterases were found to catalyze perhydrolysis but the preference of the enzymes for hydrogen peroxide relative to water as nucleophile was only 10–100 fold, even in the best cases. Hence, perhydrolysis proceeds with a very low efficiency in aqueous systems. Furthermore, all lipases, esterases and cholinesterases tested degrade peroxycarboxylic acids to the corresponding carboxylic acid and hydrogen peroxide. This reaction is most pronounced in the case of lipases while less so for cholinesterases. Consequently, cholinesterases are superior to the other hydrolases studied in catalyzing net formation of peracids in aqueous systems. In organic solvents, immobilized lipases efficiently catalyze formation of peracids from either triglycerides or the parent carboxylic acid. Proteases and phospholipase A-2 were found to neit...

Lipase catalyzed synthesis of long chain peroxycarboxylic acids from hydrogen peroxide and free carboxylic acid was investigated. A 51% yield of peroxytetradecanoic acid was achieved when using a two phase system of toluene and water. The peroxy acids thus formed were applied for in situ oxidation of alkenes, in general leading to high yields of the corresponding epoxide. For example, a quantitative yield of cyclohexene oxide and a 94% yield of 1-hexadecene oxide was achieved in a solvent-free process.

The fatty acid specificity of the B-lipase derived from Candida antarctica was investigated in the synthesis of esters of ethyl D-glucopyranoside. The specificity was almost identical with respect to straight-chain fatty acids with 10 to 18 carbon atoms. However, lower fatty acids such as hexanoic and octanoic acid and the unsaturated 9-cis-octadecenoic acid were found to be poor substrates of the enzyme. As a consequence of this selectivity, these fatty acids were accumulated in the unconverted fraction when ethyl D-glucopyranoside was esterified with an excess of a mixture of fatty acids. This accumulation can reduce the overall effectiveness of the process as the activity of the lipase was found to be reduced when exposed to high concentrations of short-chain fatty acids. Finally, using a simplified experimental set-up, the specificity of the C. antarctica B-lipase was compared to the specificity of lipases derived from C. rugosa, Mucor miehei, Humicola, and Pseudomonas. Apart from the C. rugosa lipase...

A cyanide-metabolizing bacterium, strain DF3, isolated from soil was identified as Alcaligenes xylosoxidans subsp. denitrificans. Whole cells and cell extracts of strain DF3 catalyzed hydrolysis of cyanide to formate and ammonia (HCN + 2H2O----HCOOH + NH3) without forming formamide as a free intermediate. The cyanide-hydrolyzing activity was inducibly produced in cells during growth in cyanide-containing media. Cyanate (OCN-) and a wide range of aliphatic and aromatic nitriles were not hydrolyzed by intact cells of A. xylosoxidans subsp. denitrificans DF3. Strain DF3 hydrolyzed cyanide with great efficacy. Thus, by using resting induced cells at a concentration of 11.3 mg (dry weight) per ml, the cyanide concentration could be reduced from 0.97 M (approximately 25,220 ppm) to less than 77 nM (approximately 0.002 ppm) in 55 h. Enzyme purification established that cyanide hydrolysis by A. xylosoxidans subsp. denitrificans DF3 was due to a single intracellular enzyme. The soluble enzyme was purified approximately 160-fold, and the first 25 NH2-terminal amino acids were determined by automated Edman degradation. The molecular mass of the active enzyme (purity, greater than 97% as determined by amino acid sequencing) was estimated to be greater than 300,000 Da. The cyanide-hydrolyzing enzyme of A. xylosoxidans subsp. denitrificans DF3 was tentatively named cyanidase to distinguish it from known nitrilases (EC 3.5.5.1) which act on organic nitriles.

Recognition of the advantages of the use of lipases relative to traditional chemical processes indicates that lipases may be expected to gain in importance in the enzyme market. Development of lipase technologies for the synthesis of novel compounds will probably also result in their expansion into new areas, and a major impact on a range of industries.

6-O-Monoesters of alkyl glucopyranosides have been prepared on a large scale in a more than 90% yield by direct enzyme-catalysed esterification of glucopyranosides with long chain fatty acids in a solvent-free process

LCZ696 displays several surprising features, such as an intrinsic stabilization of the supramolecular complex by monovalent multi-coordinated sodium cations and water molecules. In addition, to the best of our knowledge, the compound is the first example of a dual-acting pharmaceutical built as a supramolecular complex delivering two pharmacologic effects—angiotensin receptor 1 (AT1) blockage and neprilysin (NEP) inhibition.

Epoxidation of alkenes was achieved under extremely mild conditions by employing peroxycarboxylic acids formed continuously in situ by lipase-catalysed perhydrolysis of the corresponding carboxylic acids.

The use of lipases as catalysts in organic synthesis was exemplified by the regiospecific preparation of 6-O-acyl ethyl glucosides using a lipase derived from Candida antarctica. Optimal reaction conditions were successfully predicted using an artificial neural network as computing tool. The fatty acyl glucosides were found to be efficient nonionic surface active materials usable in a wide range of applications. A novel lipase catalyzed synthesis of peroxycarboxylic acids and concomitant lipase mediated oxidation was investigated. Using this method, epoxides were generally obtained in high yields from the corresponding alkenes. Finally, the recent determination of the X-ray structure of a lipase inhibitor complex and studies of lipase inhibitor interactions provide novel insight into the mode of action and selectivity properties of lipases.

1-Acyl-3-O-β- d -galactopyranosylglycerides have been prepared by β-galactosidase catalysed trans -galactosidation of lactose ( 1 ) or o-nitrophenyl galactopyranoside ( 4 ) with 2,3-epoxypropanol ( 2 ) and subsequent opening of the so formed 1-O-β- d -galactopyranosyl-2,3-epoxypropanol ( 3 ) with a fatty acid.

α-Acetolactate decarboxylase isolated from Enterobacter aerogenes strain 1033 has been applied for maturation of beer. Addition of the enzyme to freshly fermented beer effected removal of α-acetolactate and α-aceto-α-hydroxybutyrate in 24 hours at 10 °C to a level below the taste treshold of the corresponding volatile diketones, diacetyl and 2,3-pentanedione, without affecting other important properties of the beer. By comparison of organoleptic properties, the beer matured in the presence of α-acetolactate decarboxylase was judged to be of an equally satisfactory quality when compared with conventionally prepared beer. The evidence suggest that apart from removal of diacetyl, 2,3-pentanedione and the precursors of these compounds from fermented beer no other important events related to flavour development occur during maturation of the type of beer studied. Consequently, it is concluded, that application of enzymes may allow flavour maturation of beer to be carried out in less than 24 hours.

α-Acetolactate decarboxylase has been purified to homogeneity, by fast protein liquid chromatography and high performance elution chromatography, from a partially purified α-acetolactate decarboxylase preparation from Lactobacillus casei DSM 2547. The pure enzyme exhibited a specific activity of 375 kU·mg−1 and exerted its optimal activity at pH 4.5 to 5.0 and at a temperature of 40°C. Its isoelectric point was estimated to pH 4.7 and its molecular weight was found to be 48,000. The enzyme was inhibited by o-phenanthroline and could be partially reactivated by zinc ions. An HPLC method for the determination of α-acetolactate is described.

An authentic mixture of 1,2-, 1,4- and 1,6-dihydro-NAD was characterized by high pressure liquid chromatography. Pure 1,6-dihydro-NAD isolated from this mixture was shown to be a potent inhibitor of lactate dehydrogenase and to exhibit an UV spectrum identical to that of an extensively purified lactate dehydrogenase inhibitor generated by exposing NADH to moisture. The humidity induced inhibitor, which could not be separated from NADH by DEAE chromatography, cochromatographed with 1,6-dihydro-NAD during both DEAE and high pressure liquid chromatography and is therefore presumably identical to 1,6-dihydro-NAD.

The ability to generate α-acetolactate decarboxylase activity has been detected among bacteria but not among members of any other group of microorganisms. Among bacteria found to produce an α-acetolactate decarboxylase several, such as strains of Bacillus and Lactobacillus, are potential sources of decarboxylases which may be applied in brewing.

The identity of the product obtained by sodium borohydride reduction of NAD+ as 1,6-dihydro-NAD has been verified by13C NMR spectroscopy. The behaviour of this compound during chromatography on Sephadex G-15 has been found identical with that of the humidity induced inhibitor detected in NADH preparations and postulated to be identical with 1,6-dihydro-NAD. Evidence is presented that this inhibitor is responsible for the bulk of the inhibitory effect developed in moist NADH preparations and that it is generated through a bimolecular reaction between NADH and NAD+ which in essence is a NAD+ catalyzed double bond rearrangement of NADH effected by transfer of hydride anions from NADH to NAD+. One implication of these findings, that removal of NAD+ from NADH preparations should convey increased stability to the reduced cofactor, has been verified. The structure of the lactate dehydrogenase inhibitors described in the literature is discussed.