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Biopolymers on the cell surface are very important for protecting microorganisms from environmental stresses, as well as storing nutrients and minerals. Synthesis of biopolymers is well studied, while studies on the modification and degradation processes of biopolymers are limited. One of these biopolymers, poly-γ-glutamic acid (γ-PGA), is produced by Bacillus species. Bacillus subtilis PgdS, possessing three NlpC/P60 domains, hydrolyses γ-PGA. Here, we have demonstrated that several dl-endopeptidases with an NlpC/P60 domain (LytE, LytF, CwlS, CwlO, and CwlT) in B. subtilis digest not only an amide bond of d-γ-glutamyl-diaminopimelic acid in peptidoglycans but also linkages of γ-PGA produced by B. subtilis. The hydrolase activity of dl-endopeptidases towards γ-PGA was inhibited by IseA, which also inhibits their hydrolase activity towards peptidoglycans, while the hydrolysis of PgdS towards γ-PGA was not inhibited. PgdS hydrolysed only the d-/l-Glu‒d-Glu linkages of d-Glu-rich γ-PGA (d-Glu:l-Glu=7 : 3) and l-Glu-rich γ-PGA (d-Glu:l-Glu=1 : 9), indicating that PgdS can hydrolyse only restricted substrates. On the other hand, the dl-endopeptidases in B. subtilis cleaved d-/l-Glu‒d-/l-Glu linkages of d-Glu-rich γ-PGA (d-Glu:l-Glu=7 : 3), indicating that these enzymes show different substrate specificities. Thus, the dl-endopeptidases digest γ-PGA more flexibly than PgdS, even though they are annotated as “dl-endopeptidase, digesting the d-γ-glutamyl-diaminopimelic acid linkage (d‒l amino acid bond)”.

Purpose The authors hypothesized that a muscle relaxant would have no meaningful difference in intubation conditions during nasal intubation under remifentanil and propofol anesthesia. Materials and Methods This parallel-group, double-blinded, randomized controlled trial included 44 patients who received saline (S group; n = 22) or rocuronium (R group; n = 22). In addition to remifentanil 0.5 μg/kg per minute and propofol 5 mg/kg per hour, propofol 0.5 mg/kg was administered until loss of consciousness. Nasal intubation was performed 10 minutes after administration of R or S 0.6 mg/kg. Significant differences in intubation conditions and salivary amylase levels before and after intubation were tested (P Results Vocal cord status (P = .003) and response to intubation or cuff filling (P = .008) were significantly different, but intubation conditions were not. Salivary amylase level was significantly lower with R administration (P = .022). No patient complained of postoperative throat pain and hoarseness. Conclusion Muscle relaxants during nasal intubation performed after bolus administration of propofol 0.9 mg/kg in addition to 10 minutes of remifentanil 0.5 μg/kg per minute plus propofol 5 mg/kg per hour are unnecessary.

In this clinical study we tried to find out the clinical significance of positive blood cultures between Jan. 1984 and Dec. 1989 in the Nagasaki Rosai Hospital. In this period the association between the isolated bacteria from blood cultures (398 specimens: 17.9%) and clinical background were evaluated. Each year the positive cultures were seen in about 18-20%. The distribution of bacteria showed increase percentage of the gram-positive organisms such as coagulase-negative Staphylococcus. Gram-negative organisms in included P. aeruginosa, A. calcoaceticus and E. coli. A. calcoaceticus was frequently found from the dept. of neurosurgery. Fungus, mostly Candida, was isolated in about 10-20%. The specimens were provided from department of internal medicine (62.9%) and neurosurgery (22.8%). An analysis of 213 episodes of 188 bacteremic cases was made. The onset of bacteremia had two peaks, 24 h or 1 month, after admission. The primary infected sites were the urinary tract (26.7%), respiratory system (14.5%) and central nervous system (6.1%). The central venous catheter was an important infected site. The major underlying diseases included acute cerebrovascular diseases, cardiac failure due to valvular heart diseases or acute myocardial infarction and/or iatrogenic immunocompromised state. The major complications were disseminated intravascular coagulation (DIC) (24.4%) and multiple organ failure (MOF) (8.9%). Half of the DIC episodes was caused by gram-positive cocci such as CNS, E. faecalis and MRSA. 68.4% of MOF episodes was associated with gram-negative bacteria. While the remainder was caused by gram-positive cocci including CNS and MRSA.(ABSTRACT TRUNCATED AT 250 WORDS)

Dimethylpiperidinones and dimethylmethylenepiperidines have been hydrogenated over several Group 8, 9 and 10 transition metal catalysts and the stereochemistry of the products compared with those of the carbocyclic analogues. The results obtained suggest that intramolecular interactions between the nitrogen lone pair and the unsaturated bond play a major role in determining the stereochemistry of hydrogenation.

We used lipopolysaccharide (LPS) to activate microglia that play an important role in the brain immune system. LPS injected into the rat hippocampus CA1 region activated microglial cells resulting in an increased production of interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha in the hippocampus during the initial stage of treatment. Immunostaining for IL-1beta was increased at 6 hr after LPS injection. IL-1beta-immunopositive cells were co-localized with immunostaining for CD11b. Subacute treatment with LPS by the same route for 5 days caused long-term activation of microglia and induced learning and memory deficits in animals when examined with a step-through passive avoidance test, but histochemical analysis showed that neuronal cell death was not observed under these experimental conditions. The increased expression of the heme oxygenase-1 (HO-1) gene, an oxidative stress maker, was observed. However, the genetic expression of brain-derived neurotrophic factor (BDNF) and its receptor, TrkB, decreased during the course of LPS treatment. We found decreases in [3H]MK801 binding in the hippocampus CA1 region by LPS-treatment for 5 days. The data shows that glutamatergic transmission was attenuated in the LPS-treated rats. These results suggest that long-term activation of microglia induced by LPS results in a decrease of glutamatergic transmission that leads to learning and memory deficits without neuronal cell death. The physiologic significance of these findings is discussed.

In Japan, we experienced the first case of Hafnia alvei septicemia with shock and disseminated intravascular coagulation (DIC) in an adult with postoperative lung cancer. A 63 year-old male, who had been followed up in our department since 1987, was admitted to our hospital with the complaints of fever, hemoptysis and dyspnea on June 25, 1989. After admission, he was treated with sulbactam/cefoperazone 4 g/day intravenously for suspicion of respiratory-tract infection. After antibiotic administration, the fever subsided and the general condition became almost good. The patient experienced fever again after the antibiotic was stopped. For this reason subsequent Clavulanic acid/Amoxicillin, Flomoxef, and Ceftazidime was administered, but was not effective. Therefore septicemia was suspected and blood culture was done. The bacteria isolated from blood culture was identified as Hafnia alvei. Hafnia alvei is a gram-negative organism belonging to the Enterobacteriaceae family and quite rare pathogen in human.

Dimethylpiperidinones and dimethylmethylenepiperidines have been hydrogenated over several Group 8, 9 and 10 transition metal catalysts and the stereochemistry of the products compared with those of the carbocyclic analogues. The results obtained suggest that intramolecular interactions between the nitrogen lone pair and the unsaturated bond play a major role in determining the stereochemistry of hydrogenation.

OISHI, K., YAMAMOTO, M., YOSHIDA, T., IDE, M. and MATSUMOTO, K. Opsonic Activity of Plasma Fibronectin for Staphylococcus aureus by Human Alveolar Macrophages: Inefficacy of Trypsin-Sensitive Staphylococcal Fibronectin Receptor. Tohoku J. exp. Med., 1986, 149 (1), 95-102-The binding of 125I-fibronectin (FN) to some bacteria and the phagocytic activity of human alveolar macrophages (AM) by a culture method using 3H-labelled bacteria were examined. FN-binding of Staphylococcus aureus (S. aureus) was higher than that of gram-negative rods and was reduced markedly by trypsin-treatment. FN enhanced the uptake of S. aureus by AM in dose dependent manner. To determine whether FN-binding to S. aureus mediates the promotion of staphylococcal phagocytosis, we compared the uptake of non-treated S. aureus with that of trypsin-treated bacteria by AM. No significant difference was found between the uptake of these bacteria and no effect of FN-binding to S. aureus on the phagocytic activity. It is concluded that FN plays an essential role as a non-immune opsonin for S. aureus in the human lung which is found to be abundunt in FN, and that FN-binding to S. aureus is probably not related to this effect.

Plasma fibronectin (FN) binding to bacteria and its effect of the opsonic activity on the phagocytosis of them by human alveolar macrophages (AM) was investigated. The binding of 125I-FN to Staphylococcus aureus (S. aureus: 209-P) was proportional to the amount of FN added, and was inhibited by adding non-ladiolabeled FN. Haemophilus influenzae (H. inf: 85-237) was less reactive than S. aureus. FN alone was a poor opsonin for S. aureus, but FN promoted the phagocytosis of S. aureus by AM in dose dependent manner on condition that the reactions were carried out with FN depleted serum at the higher bacteria to AM ratio. On the other hand, the phagocytosis of H. inf was not affected by FN at the higher bacteria to AM ratio. These results suggested that FN binding to bacteria might contribute to the promotion of the bacterial phagocytosis by AM in cooperation with serum factor.

To investigate the occurrence of Branhamella catarrhalis respiratory tract infections in 109 outpatients with pneumoconiosis, clinical and bacteriological studies were performed during a 4-year period from April 1984 to March 1988. B. catarrhalis was isolated in 26 patients; only three of these received continuous corticosteroid treatment. The incidence of B. catarrhalis respiratory tract infections increased gradually during the years 1984-1986, but decreased for the first time in 1987 compared with the previous year. There was a seasonal variation in isolations with a peak incidence during the winter, a pattern in contrast to Haemophilus influenzae. Almost all isolates produced beta-lactamase. B. catarrhalis found in mixed culture was usually in association with H. influenzae or Streptococcus pneumoniae. The isolation rates for B. catarrhalis in sputum of patients with pneumoconiosis followed those of H. influenzae and S. pneumoniae, and almost all strains were positive for beta-lactamase, so B. catarrhalis should be admitted that it is a primary pathogen.