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We discover a new cavitation phenomenon in amorphous polymers sandwiched between two thick slide glasses from the static melt induced by thermal treatment. By quenching atactic polystyrene (aPS) samples from the static melt under the glass transition temperature (Tg) and annealing them above Tg for thick slide glasses, cavities are created to relax the negative pressure. Cavity growth undergoes an Ostwald ripening-like process in cases of large molecular weight, while it undergoes a viscous fingering process in cases of small molecular weight. The induction time for cavity formation is found to decrease with the increase of the annealing temperature and with the decrease of molecular weight. In contrast, no cavities are observed in an aPS sample between two thin cover glasses because the negative pressure can be relaxed by bending the whole thin cover glasses. We discover a new cavitation phenomenon in amorphous polymers sandwiched between two thick slide glasses from the static melt induced by thermal treatment. By quenching atactic polystyrene samples from the static melt under the glass transition temperature (Tg) and annealing them above Tg, cavities are created to relax the negative pressure. Cavity growth undergoes an Ostwald ripening-like process in cases of large molecular weight while it undergoes a viscous fingering process in cases of small molecular weight.

Background Pneumoperitoneum and a steep Trendelenburg position during robot-assisted laparoscopic prostatectomy have been demonstrated to promote a cranial shift of the diaphragm and the formation of atelectasis in the dorsal parts of the lungs. However, neither an impact of higher positive end-expiratory pressure (PEEP) on preserving the ventilation in the dorsal region nor its physiologic effects have been fully examined. The authors hypothesized that PEEP of 15 cm H2O during robot-assisted laparoscopic prostatectomy might maintain ventilation in the dorsal parts and thus improve lung mechanics. Methods In this randomized controlled study, 48 patients undergoing robot-assisted laparoscopic prostatectomy were included in the analysis. Patients were assigned to the conventional PEEP (5 cm H2O) group or the high PEEP (15 cm H2O) group. Regional ventilation was monitored using electrical impedance tomography before and after the establishment of pneumoperitoneum and 20° Trendelenburg position during the surgery. The primary endpoint was the regional ventilation in the dorsal parts of the lungs while the secondary endpoints were lung mechanics and postoperative lung function. Results Compared to that in the conventional PEEP group, the fraction of regional ventilation in the most dorsal region was significantly higher in the high PEEP group during pneumoperitoneum and Trendelenburg position (mean values at 20 min after taking Trendelenburg position: conventional PEEP, 5.5 ± 3.9%; high PEEP, 9.9 ± 4.7%; difference, –4.5%; 95% CI, –7.4 to –1.6%; P = 0.004). Concurrently, lower driving pressure (conventional PEEP, 14.9 ± 2.5 cm H2O; high PEEP, 11.5 ± 2.8 cm H2O; P < 0.001), higher lung dynamic compliance, and better oxygenation were demonstrated in the high PEEP group. Postoperative lung function did not differ between the groups. Conclusions Application of a PEEP of 15 cm H2O resulted in more homogeneous ventilation and favorable physiologic effects during robot-assisted laparoscopic prostatectomy but did not improve postoperative lung function. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

Herein, we describe the design, synthesis, and structure–activity relationships of novel benzylpyrazole acylsulfonamides as non-thiazolidinedione (TZD), non-carboxylic-acid-based peroxisome proliferator-activated receptor (PPAR) γ agonists. Docking model analysis of in-house weak agonist 2 bound to the reported PPARγ ligand binding domain suggested that modification of the carboxylic acid of 2 would help strengthen the interaction of 2 with the TZD pocket and afford non-carboxylic-acid-based agonists. In this study, we used an acylsulfonamide group as the ring-opening analog of TZD as an isosteric replacement of carboxylic acid moiety of 2; further, preliminary modification of the terminal alkyl chain on the sulfonyl group gave the lead compound 3c. Subsequent optimization of the resulting compound gave the potent agonists 25c, 30b, and 30c with high metabolic stability and significant antidiabetic activity. Further, we have described the difference in binding mode of the carboxylic-acid-based agonist 1 and acylsulfonamide 3d.

Insulin stimulates translocation of glucose transporter isoform type 4 (GLUT4) and the insulin-responsive aminopeptidase (IRAP) from an intracellular storage pool to the plasma membrane in muscle and fat cells. A role for the cytoskeleton in insulin action has been postulated, and the insulin signaling pathway has been well investigated; however, the molecular mechanism by which GLUT4/IRAP-containing vesicles move from an interior location to the cell surface in response to insulin is incompletely understood. Here, we have screened for IRAP-binding proteins using a yeast two-hybrid system and have found that the C-terminal domain of FHOS (formin homolog overexpressed in spleen) interacts with the N-terminal cytoplasmic domain of IRAP. FHOS is a member of the Formin/Diaphanous family of proteins that is expressed most abundantly in skeletal muscle. In addition, there are two novel types of FHOS transcripts generated by alternative mRNA splicing. FHOS78 has a 78-bp insertion and it is expressed mainly in skeletal muscle where it may be the most abundant isoform in humans. The ubiquitously expressed FHOS24 has a 24-bp insertion encoding an in-frame stop codon that results in a truncated polypeptide. It is known that some formin family proteins interact with the actin-binding profilin proteins. Both FHOS and FHOS78 bound to profilin IIa via their formin homology 1 domains, but neither bound profilin I or IIb. Overexpression of FHOS and FHOS78 resulted in enhanced insulin-stimulated glucose uptake in L6 cells to similar levels. However, overexpression of FHOS24, lacking the IRAP-binding domain, did not affect insulin-stimulated glucose uptake. These findings suggest that FHOS mediates an interaction between GLUT4/IRAP-containing vesicles and the cytoskeleton and may participate in exocytosis and/or retention of this membrane compartment.

Preanesthetic evaluation is essential for the perioperative period. We report 2 preoperative patients with benign disease, whose preoperative chest radiography revealed intrathoracic malignant tumors. Case 1: A woman in her eighties with vascular necrosis of the femoral head was scheduled for bipolar hip arthroplasty under general anesthesia. On preanesthetic evaluation, widened mediastinum was detected on preoperative chest radiography. Instead of the scheduled operation, she underwent thoracoscopic surgery under general and epidural anesthesia. She was diagnosed with malignant thymoma. Case 2: A woman in her thirties with bilateral oviduct obstruction was scheduled for laparoscopic surgery. On preanesthetic evaluation, right middle lung lesion was detected. She underwent thoracoscopic biopsy under general and epidural anesthesia, and was diagnosed with malignant lymphoma. The result of preanesthetic chest radiography is reported to change the perioperative treatment only in 0.1%; our cases indicate the importance of preanesthetic evaluation of chest radiography in detecting possible underlying disease in the preoperative patient.

In our search for a novel class of non-TZD, non-carboxylic acid peroxisome proliferator-activated receptor (PPAR) γ agonists, we explored alternative lipophilic templates to replace benzylpyrazole core of the previously reported agonist 1. Introduction of a pentylsulfonamide group into arylpropionic acids derived from previous in-house PPARγ ligands succeeded in the identification of 2-pyridyloxybenzene-acylsulfonamide 2 as a lead compound. Docking studies of compound 2 suggested that a substituent para to the central benzene ring should be incorporated to effectively fill the Y-shaped cavity of the PPARγ ligand-binding domain (LBD). This strategy led to significant improvement of PPARγ activity. Further optimization to balance in vitro activity and metabolic stability allowed the discovery of the potent, selective and orally efficacious PPARγ agonist 8f. Structure-activity relationship study as well as detailed analysis of the binding mode of 8f to the PPARγ-LBD revealed the essential structural features of this series of ligands.

The chemical structure of a new dipeptide antibiotic, TAN-1057 A, isolated from the broth filtrate of Flexibacter sp. PK-74 was determined to be (3′S, 5S)-5-[N-methyl-N-(3′-amino-6′-guanidinohexanoyl)amino]5,6-dihydro-2-ureido-4(1H)-pyrimidone. The antibiotic was specifically active against staphylococcus species including methicillin-resistant strains.

The chemical structure of a new dipeptide antibiotic, TAN-1057 A, isolated from the broth filtrate of Flexibacter sp. PK-74 was determined to be (3′S, 5S)-5-[N-methyl-N-(3′-amino-6′-guanidinohexanoyl)amino]5,6-dihydro-2-ureido-4(1H)-pyrimidone. The antibiotic was specifically active against staphylococcus species including methicillin-resistant strains.

A Gram-negative bacterium was found to produce new antibacterial antibiotics, sperabillins A, B, C and D, and the producing bacterium was characterized and identified as Pseudomonas fluorescens YK-437. Sperabillins were isolated by column chromatographies using cation-exchange resins, activated carbon and cation-exchange Sephadex, and preparative reverse-phase HPLC. Sperabillins showed antibacterial activity against Gram-negative and Gram-positive bacteria including antibiotic-resistant strains of Pseudomonas aeruginosa and Staphylococcus aureus. Sperabillin A inhibited DNA, RNA, protein, and cell wall biosynthesis in Escherichia coli. Sperabillins showed good protective effects in experimentally infected mice.

Modification of sperabillins was carried out. The 2-amidinoethylamino moiety was removed by brief acidic hydrolysis. The 2, 4-hexadienoyl moiety was hydrogenated to the hexanoyl moiety and this was cleaved by an enzymatic reaction using the cells of Pseudomonas acidovorans IFO 13582. The 2-amidinoethylamino and the 2, 4-hexadienoyl moieties were replaced with other groups. The derivative which was prepared by condensation of two molar amounts of dehexadienoylsperabillin A with (E, E)-muconic acid showed better protective effects than sperabillin A against Gram-negative bacteria.

Two Gram-negative bacteria were found to produce the new antibacterial antibiotics TAN-1057 A, B, C arid D. The producing bacteria were characterized and designated as Flexibacter sp. PK-74 and PK-176. These antibiotics were active against Gram-negative and Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus. TAN-1057 A inhibited protein biosynthesis in Escherichia coli and S. aureus. It showed excellent protective effects against an experimental methicillin-resistant S. aureus infection in mice.

Novel iron-containing peptide antibiotics, ferrocins A, B, C and D, have been isolated from the culture filtrate of Pseudomonas fluorescens YK-310. These antibiotics were purified by butanol extraction, followed by column chromatography using adsorption resin, silica gel and preparative reverse-phase HPLC. The structures of ferrocins were elucidated using spectroscopic and degradative methods. Ferrocins contain three hydroxamate moieties per ferric ion which forms an octahedral iron complex.

A Gram-negative bacterium was found to produce new iron-containing peptide antibiotics, ferrocins A, B, C and D, and the producing bacterium was characterized and identified as Pseudomonas fluorescens YK-310. These new antibiotics showed antibacterial activity against Gram-negative bacteria in vitro. Although the ferrocins showed similar antibacterial activity against both Escherichia coli and Pseudomonas aeruginosa on the standard assay media, they showed strong therapeutic effects selectively against P. aeruginosa in experimentally infected mice.

Two new nucleotide antibiotics, fosfadecin and fosfocytocin, have been isolated from the culture filtrates of Pseudomonas viridiflava PK-5 and Pseudomonas fluorescens PK-52, respectively. These antibiotics were purified by column chromatographies using adsorption, gel filtration and ion exchange resins. On the basis of the spectroscopic and degradation studies, the chemical structures of fosfadecin and fosfocytocin were determined. These antibiotics were either enzymatically or chemically hydrolyzed to generate fosfomycin and a new antibiotic, fosfoxacin, which are also produced in the culture filtrates. They showed antibacterial activity against Gram-positive and Gram-negative bacteria. The antibacterial activity of these nucleotide antibiotics was weaker than that of fosfomycin and fosfoxacin.

Lactivicin is moderately active against a wide range of Gram-negative bacteria and highly active against Gram-positive bacteria. It shows various biological activities commonly observed with beta-lactam antibiotics, such as higher activity against beta-lactam hypersensitive mutants than against their parents, sensitivity to beta-lactamases, inhibitory activity against beta-lactamases and ability to induce beta-lactamase activity. The primary lethal target of lactivicin in Escherichia coli is highly likely to be penicillin-binding protein (PBP) 1; lactivicin strongly lysed E. coli cells with induction of spheroplasts at its MIC, and showed high affinity for PBPs 1A and 1B. At concentrations above x 5 MIC, however, lactivicin dominantly exhibited secondary antibacterial action possibly owing to inhibition of crucial SH proteins engaged in the fundamental membrane functions. In contrast, against Bacillus subtilis, lactivicin showed the typical beta-lactam action under a wide range of concentrations. It showed high affinity for PBPs 1, 2 and 4, the possible lethal targets of beta-lactam antibiotics in this organism. In conclusion, lactivicin is the first non-beta-lactam antibiotic showing beta-lactam action through binding to PBPs.

The steady-state kinetics of alcohol dehydrogenases (alcohol:NAD + oxidoreductase, EC 1.1.1.1 and alcohol:NADP + oxidoreductase, EC 1.1.1.2), lactate dehydrogenases ( l -lactate:NAD + oxidoreductase, EC 1.1.1.27 and d -lactate:NAD + oxidoreductase, EC 1.1.1.28), malate dehydrogenase ( l -malate:NAD + oxidoreductase, EC 1.1.1.37), and glyceraldehyde-3-phosphate dehydrogenases [ d -glyceraldehyde-3-phosphate:NAD + oxidoreductase (phosphorylating), EC 1.2.1.12] from different sources (prokaryote and eukaryote, mesophilic and thermophilic organisms) have been studied using NAD(H), N 6 -(2-carboxyethyl)-NAD(H), and poly(ethylene glycol)-bound NAD(H) as coenzymes. The kinetic constants for NAD(H) were changed by carboxyethylation of the 6-amino group of the adenine ring and by conversion to macromolecular form. Enzymes from thermophilic bacteria showed especially high activities for the derivatives. The relative values of the maximum velocity ( NAD = 1) of Thermus thermophilus malate dehydrogenase for N 6 -(2-carboxyethyl)-NAD and poly(ethylene glycol)-bound NAD were 5.7 and 1.9, respectively, and that of Bacillus stearothermophilus glyceraldehyde-3-phosphate dehydrogenase for poly(ethylene glycol)-bound NAD was 1.9.

Cephabacin F group antibiotics with a 7-formylamino substituent showed antibacterial activity against a wide variety of bacteria including beta-lactamase-producing clinical isolates and anaerobic bacteria. Cephabacin H group antibiotics without the substituent showed more potent activity against Gram-positive bacteria than cephabacin F group antibiotics, but were not active against Gram-negative bacteria producing beta-lactamases. Cephabacin F group antibiotics were highly resistant to hydrolysis by various types of beta-lactamases and showed strong inhibitory activity against a cephalosporinase of Proteus vulgalis GN 4413 due to the 7-formylamino substituent. Mode of action of cephabacin F1 and H1 was examined using Escherichia coli and Bacillus subtilis as the test organisms. They showed strong lytic activity against these organisms and inhibited their peptidoglycan synthesis. Cephabacin F1 had the highest affinity for penicillin-binding protein (PBP) 1 in E. coli and PBP 4 in B. subtilis. Cephabacins showed a protective effect in experimentally infected mice.

A Gram-negative bacterium produces new monocyclic beta-lactam antibiotics with a formylamino substituent, named formadicins A, B, C and D. The producing bacterium was taxonomically characterized and designated as Flexibacter alginoliquefaciens sp. nov. YK-49. Formadicins have narrow antibacterial spectra. They are highly active against some species of Pseudomonas, Proteus and Alcaligenes. Of the four, formadicin C shows the most potent antibacterial activity. Several amino acids such as glycine, D-alanine and D-leucine were antagonistic against formadicins. Formadicins, especially formadicins A and C having the formylamino substituent bound to the 3-position of a beta-lactam nucleus, were highly resistant to hydrolysis by various types of beta-lactamases. Formadicins A and C showed affinity for penicillin-binding proteins (PBPs) 1A and 1B in Pseudomonas aeruginosa IFO 3080, but formadicin B and nocardicin A showed affinity only for PBP 1B. Formadicins A and C did not lyse Escherichia coli LD-2 solely at their MICs, but when combined with mecillinam each induced a rapid lysis of this organism.

New 7-methoxycephem antibiotics were found in culture filtrates of a bacterium isolated from a plant and named cephabacin M1-6. They are the first members of 7-methoxycephem antibiotics of bacterial origin. The producing organism was taxonomically characterized and identified as Xanthomonas lactamgena YK-431; other strains of this species have recently been reported to produce cephabacin F and H group antibiotics. Cephabacin M1-6 exhibited moderate antibacterial activity against Gram-negative and Gram-positive bacteria. Cephabacin M1-6 were as stable as cephamycin C to cephalosporinases. They showed inhibitory activity against a cephalosporinase of Proteus vulgaris GN 4413. The mode of action of cephabacin M, was examined using Escherichia coli and Bacillus subtilis as test organisms; primary lethal targets of cephabacin M1 are penicillin-binding protein (PBP) 1 in E. coli and PBP 4 in B. subtilis.

In the search for new beta-lactam antibiotics of natural origin, the discoveries of cephamycins and sulfazecins (monobactams) were important turning points in that they accelerated many screening efforts aimed at other new compounds. In our target-directed screening for beta-lactam antibiotics using beta-lactam hypersensitive mutants, we have examined Gram-negative bacteria isolated from natural habitats and have recently reported several types of beta-lactam antibiotics such as cephabacins and formadicins. Here we report a novel antibiotic, lactivicin, found using this system. Although lactivicin has various biological activities commonly observed in beta-lactam antibiotics, it does not possess a beta-lactam ring in its molecule, but has the unique structure of a dicyclic dipeptide.

New monocyclic beta-lactam antibiotics, formadicins A, B, C and D, were isolated from the culture filtrate of Flexibacter alginoliquefaciens sp. nov. YK-49 by various types of column chromatography and preparative reverse-phase HPLC. Their structures were determined by spectroscopic analyses and degradation studies. They have a nocardicin-type skeleton and a formylamino group at the 3- or 12-position. Formadicins A and B each have a D-glucuronide moiety and give formadicins C and D, respectively, upon hydrolysis using beta-D-glucuronidase.

Three Gram-negative bacteria produce new cephem antibiotics, named cephabacins, with unique 3-side chains. Cephabacins include F group antibiotics with a 7-formylamino substituent and H group antibiotics without the substituent. The producing bacteria were taxonomically characterized and designated as Lysobacter lactamgenus sp. nov. YK-90 and Xanthomonas lactamgena sp. nov. YK-278 and YK-280.

The kinetic properties sof a continuous enzyme reactor containing rabbit muscle lactate dehydrogenase, horse liver alcohol dehydrogenase and poly(ethylene glycol)-bound NAD (PEG-NAD) were investigated experimentally and theoretically. The enzymes and PEG-NAD were retained in the reactor with an ultrafiltration membrane, and the substrates (pyruvate and ethanol) were fed continuously. The eractions of the dehydrogenases were coupled by the recycling of dsthe cofactor. The steady-state concentration of L-lactate, one of the products, was measured under different experimental conditions and compared with the corresponding theoretical value. The theoretical value was calculated based on a simplified ordered bi-bi mechanism for the individual enzyme reactions, of which kinetic constants were determined by independent kinetic studies. Differences were found between the kinetic constants of the enzymes for NAD(H) and PEG-NAD(H). The steady-state values obtained by continuous operation were lower than those calculated, possibly due to the simplification made for the kinetic model; but thfed continuously. The eractions of the dehydrogenases were coupled by the recycling of dsthe cofactor. The steady-state concentration of L-lactate, one of the products, was measured under different experimental conditions and compared with the corresponding theoretical value. The theoretical value was calculated based on a simplified ordered bi-bi mechanism for the individual enzyme reactions, of which kinetic constants were determined by independent kinetic studies. Differences were found between the kinetic constants of the enzymes for NAD(H) and PEG-NAD(H). The steady-state values obtained by continuous operation were lower than those calculated, possibly due to the simplification made for the kinetic model; but there was general agreement between them in the dependence on the experimental conditions. The steady-state behavior of the enzyme reactor was explained semi-quantitatively by the simple kinetic model.