Remarkably high asymmetric amplification in the chiral lanthanide complex-catalyzed hetero-Diels-Alder reaction: first example of the nonlinear effect in ML3 system

[reaction: see text] A remarkably high asymmetric amplification was realized in the Yb[(R)-BNP]3-catalyzed hetero-Diels-Alder reaction as the first example in the metal/chiral ligand 1:3 system. The mechanism may be explained by the autogenetic formation of the enantiopure complex as the most active catalyst. The enantiomer-discriminative formation of homochiral ML3 complexes is quite general within the lanthanide metal ions with similar ionic radii to that of the ytterbium ion.

Cyfra 21-1 as a marker of lung cancer.

The utility of cytokeratin fragment (Cyfra) 21-1, a new tumor marker, was investigated in 100 patients with lung cancer. Sandwich enzyme immunoassay detected Cyfra 21-1 in the sera of 60% of patients. Sensitivity of this marker was especially high (86.4%) for squamous cell carcinoma, exceeding that of a similar marker, squamous cell carcinoma antigen (SCC, 54.5%). In contrast, sensitivity of Cyfra 21-1 was relatively low for adenocarcinoma (52.6%) and for small cell carcinoma (50%). We conclude that Cyfra 21-1 is of value in diagnosis of lung cancer, particularly squamous cell carcinoma.

Antimicrobial activities of benzylpenicillin in combination with Traditional Herbal Medicines against ß-Lactamase-producing bacteria.

The antibacterial activities of benzylpenicillin (PCG) alone or in combination with herbal medicines, Jyuzen-Taiho-Toh (JTT), Hotyu-Ekki-Toh (HET) and Tohki-Rikuoh-Toh (TRT), were examined against penicillinase (PCase)-producing organisms using an agar dilution method. All of the combinations of PCG and each herbal medicine substantially enhanced the activity of PCG against carbenicillin resistant Pseudomonas aeruginosa PAO2142RP(r)/pMG26: the minimum inhibitory concentration (MIC) value was decreased eightfold. The susceptibility of E. coli strains harboring plasmid encoding PCase, types I, II, and III, respectively, increased slightly to PCG in these combinations, whereas none of these combinations produced the effect in E. coli with type IV PCase. Preincubation of various types of PCase with each herbal medicine induced a reduction in enzymatic activities. The inhibitory activity was found to increase in the following order: TRT < HET < JTT. In the case of JTT, the % inhibitions for types I, II, III, and IV PCase were found to be 104, 100, 97, and 94, respectively. The type I PCase-inhibiting activity of JTT was unaffected by heat treatment at 121°C for 15 min at neutral pH. These results suggested that the combination effect between PCG and herbal medicines might be due to the inhibitory activity of herbal medicines against the PCases.

Morphological and histochemical study of nonhemiplegic muscle in acute stroke patients manifesting respiratory failure.

There is little information on skeletal muscle changes in patients with acute stroke. We performed morphological and histochemical examinations of nonhemiplegic sternothyroid muscles biopsied at the time of tracheostomy from 13 patients with acute stroke manifesting acute respiratory failure. Degenerating and regenerating fibers were observed in all 13 specimens. Following characteristic myopathic changes suggestive of mitochondrial abnormalities were also demonstrated in a majority of patients. Namely, ragged-red fibers, focal increase in NADH-TR activity in subsarcolemmal areas and increases in acid phosphate activity were found. The changes were similar but extremely slight in control patients with acute respiratory failure due to causes other than stroke and were absent in the other control patients with adenomatous thyroid tumor. The severity and extent of the histopathological changes in the muscle fibers in patients with acute stroke were closely correlated with the duration of hypoxemia but not with such items as type of stroke, site of cerebral lesion, consciousness level, days of biopsy after the stroke, clinical outcome, levels of serum creatine kinase, myoglobin and PaO2. This acute nonhemiplegic muscle involvement was considered to be a very common complication in severe stroke patients.

[Efficacy and safety of percutaneous endoscopic gastrostomy in the elderly].

Percutaneous endoscopic gastrostomy (PEG) was performed in 32 patients with nasogastric feeding (NGF) or total parenteral nutrition (TPN), who were unable to swallow. Our cases of PEG included 10 with dementia, 8 with cerebral infarction, 8 with cerebral bleeding, 3 with gastric cancer, and others. TPN was performed after PEG for a short time. Because of the combination of TPN and PEG, there was no mortality or major complication related to the procedure. Minor complications included subcutaneous abscess and TPN catheter fever. PEG can be safely and rapidly performed. Furthermore, painless life, better cosmetic features and physical condition can be obtained with this procedure. The majority of the patients are able to return home after PEG. PEG can improve the quality of life of the patients who cannot swallow but have an intact gut.

Effects of diethyl maleate (DEM), a glutathione depletor, on prostaglandin synthesis in the isolated perfused spleen of rabbits.

To investigate the role of glutathione (GSH) on prostaglandin (PG) synthesis, isolated rabbit spleens were perfused with Tyrode's solution with or without the addition of diethyl maleate (DEM) in concentrations up to 1 mM. In the absence of DEM, PG synthesis was stimulated by the Ca2+ ionophore A23187 (20 nmole) or arachidonate (0.4 mumole). Prostaglandin (PG) E2 was a major product, accounting for 60-70% of the total cyclooxygenase products. Small amounts of PGF2 alpha, 6-keto-PGF1 alpha, PGD2 and thromboxane (Tx) B2 were also produced. When DEM was added to the perfusion medium, GSH content decreased dose-dependently with increasing DEM concentration. Lactate dehydrogenase activity was not detected in the venous effluent, indicating that DEM depleted intrasplenic GSH without causing any lysis of cellular membranes. A23187-induced production of PGs and of Tx was decreased with increasing concentrations of DEM up to 0.5 mM, whereas at 1.0 mM DEM, these products showed a tendency to increase as compared with levels at 0.5 mM DEM. However, this increase was only significant for TxB2, which returned to levels obtained in the absence of DEM. DEM 1 mM did not cause cell lysis, but it appears to perturb the cell membrane to a degree similar to that which occurs with stimulation of phospholipase A2. The small but significant increase of TxB2 with 1.0 mM DEM could be a result of decreased PGE2 isomerase activity. Perfusion with arachidonate gave virtually identical results: 1.0 mM DEM attenuated the production of all prostanoids except for TxB2 as compared with untreated controls. These results suggest that GSH contributes to the regulation and/or maintenance of PGs synthesis.