Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (2000)

From October 2000 to September 2001, we collected the specimen from 410 patients with lower respiratory tract infections in 16 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various anti-bacterial agents and antibiotics and patients' characteristics. Of 499 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 493 strains were investigated. The breakdown of the isolated bacteria were: Staphylococcus aureus 78, Streptococcus pneumoniae 73, Haemophilus infiuenzae 99, Pseudomonas aeruginosa (non-mucoid) 64, P. aeruginosa (mucoid) 14, Klebsiella pneumoniae 25, Moraxella subgenus Branhamella catarrhalis 21, etc. Of 78 S. aureus strains, those with 4 micrograms/ml or more of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) occupied 53.8%. Vancomycin and arbekacin had the most potent activities against MRSA as observed in 1999. The frequency of S. pneumoniae exhibiting low sensitivity to penicillin (penicillin-intermediate S. pneumoniae: PISP + penicillin-resistant S. pneumoniae: PRSP) was 38.4% being consistent with that in 1999 (34.7%). PRSP accounted for 11.0% of the total, being more than that in 1999 (3.0%). Carbapenems had strong activities against S. pneumoniae. Especially, panipenem inhibited the growth of all 73 strains at 0.125 microgram/ml. Generally, all drugs had strong activities against H. influenzae with MIC80s of 8 micrograms/ml or less. The drug that had the strongest activity against H. infiuenzae was levofloxacin, which inhibited the growth of 94 of the 99 strains at 0.063 microgram/ml. Tobramycin had a strong activity against P. aeruginosa (both mucoid and non-mucoid) with MIC80 of 1 microgram/ml. The mucoid strain was little isolated (14 strains) but the susceptibilities to all drugs were better than the non-mucoid strain. K. pneumoniae showed good susceptibilities to all drugs except ampicillin and the MIC80S were 2 micrograms/ml or less. Particularly, cefpirome, cefozopran, and levofloxacin had strong bactericidal activities against K. pneumoniae with MIC80s of 0.125 microgram/ml, and cefotiam, second-generation cephems, also had a favorable activity being MIC80 of 0.25 microgram/ml. Also, all drugs generally had strong activities against M. (B.) catarrhalis. MIC80s of all drugs were 2 micrograms/ml or less. The drug having the strongest activity was imipenem and levofloxacin inhibiting all 21 strains at 0.063 microgram/ml. Most of the patients with respiratory infection were aged 70 years or older, accounting for approximately a half of the total (44.4%). As for the incidence by the diseases, bacterial pneumonia and chronic bronchitis were the highest, being noted in 38.0% and 31.7% of all the patients, respectively. The bacteria frequently isolated from the patients with bacterial pneumonia were S. aureus (18.3%) and S. pneumoniae (16.1%). In contrast, H. infiuenzae (20.4%) and P. aeruginosa (both mucoid and non-mucoid: 16.7%) were frequently isolated from the patients with chronic bronchitis. Before the drug administration, the bacteria frequently isolated from all the patients were S. pneumoniae (24.3%) and H. infiuenzae (26.7%). The frequency of isolated S. pneumoniae tended to decrease with the increase in the number of administration days while that of isolated H. infiuenzae did not. The frequency of isolated P. aeruginosa tended to increase with the duration of administration. The isolated bacteria were comparable between the patients already treated with penicillins and cephems. In the patients treated with aminoglycosides, macrolides, and quinolones, P. aeruginosa was most frequently isolated (33.3 to 40.0%).     

Reverse geometrical selectivity in glucuronidation and sulfation of cis- and trans-4-hydroxytamoxifens by human liver UDP-glucuronosyltransferases and sulfotransferases

The phenolic active metabolites, cis-4-hydroxytamoxifen (cis-HO-TAM) and trans-4-hydroxytamoxifen (trans-HO-TAM), of the anti-breast-cancer drug, trans-tamoxifen (TAM), were geometrically selectively glucuronidated in the manner of cis>trans by microsomes and sulfated in the manner of trans>cis by cytosol from the liver of 10 human subjects (7 females and 3 males). There was a large individual difference in the microsomal glucuronidation of cis-HO-TAM, which correlated well with glucuronidation of 4-hydroxybiphenyl by human liver microsomes. However, there was only a slight correlation between the glucuronidation of cis-HO-TAM and trans-HO-TAM or 4-nitrophenol (NP). A small individual difference was observed for the human liver cytosolic sulfation of trans-HO-TAM, which correlated well with the sulfation of NP. Recombinant human UDP-glucuronosyltransferase (UGT)2B15 catalyzed the cis-selective glucuronidation of geometrical isomers of HO-TAM. UGTs1A1, 1A4, 1A9 and 2B7 had weak activity toward HO-TAMs with a much smaller cis-selectivity than did UGT2B15. UGTs1A3 and 1A6 had no detectable activity toward these substrates. Among the four known major sulfotransferases (SULTs) occurring in the human liver, SULT1A1 was strongly suggested to play the most important role in the hepatic cytosolic trans-selective sulfation of HO-TAM isomers. A good correlation was observed between the hepatic cytosolic sulfation of trans-HO-TAM and NP, a standard substrate for SULT1A1. SULT1E1 had slight activity toward the HO-TAMs. SULTs1A3 and 2A1 had no detectable activity toward HO-TAMs.     

Inhibitory effects of metals on ATP-induced current through P2X7 receptor in NG108-15 cells

We investigated the effects of heavy metal ions on the ATP-induced nonselective cation current through P2X7 receptor (I(NS x P2X7)) in NG108-15 cells using the whole-cell patch-clamp technique. Cu2+ inhibited the I(NS x P2X7) most potently among the metal ions investigated. Other metals such as Ni2+, Cd2+, Zn2+ and Co2+ also inhibited the I(NS x P2X7) in concentration-dependent manners. The order of potency was Cu2+ > Ni2+ > Cd2+ > Zn2+ > Co2+ with IC50 values of 16 nM, 0.79 microM, 1.2 microM, 3.0 microM and 4.6 microM, respectively. Fe3+ (10 and 100 microM) and Mn2+ (10 microM) did not affect the INS P2X7. A high concentration of Mn2+ (100 microM) slightly inhibited the I(NS x P2X7). When the concentration-response curve of ATP was obtained in the presence of 3 and 10 nM Cu2+, the maximal response but not the EC50 value appeared to be reduced, suggesting that the inhibition is not competitive. These results suggest that under physiological and toxicological conditions, metal ions, such as Cu2+, Ni2+, Cd2+, Zn2+ and Co2+, may modulate P2X7 receptor channels as inhibitors.     

Effects of anions on ATP-induced [Ca2+], increase in NG108-15 cells

We investigated the effects of anions on different P2 receptors by measuring ATP-induced increase in intracellular Ca2+ concentration ([Ca2+]i) in fura-2-loaded NG108-15 and PC12 cells. In NG108-15 cells, ATP at 100 microM and 1 mM induced a transient and a sustained [Ca2+]i increase, respectively. The former, but not the latter, was inhibited by U-73122, indicating that the former was via the P2Y2 receptor and the latter via the P2X7 receptor. When external Cl- was replaced by other anions, the [Ca2+]i increase mediated by the P2Y2 receptor was not changed, but that mediated by the P2X7 receptor varied in the order of aspartate- > methanesulfonate > Cl- > Br > or = I-. In PC12 cells, transient [Ca2+]i increases mediated by the P2Y2 and P2X2 receptors were not affected by various anions. These results suggest that modulation by anions is unique to the P2X7 receptor and does not occur in P2Y2 and P2X2 receptors. This may be because the mechanism of ATP binding to the P2X7 receptor may be different than that to other P2 receptors.     

Differential effects of bupivacaine enantiomers,ropivacaine and lidocaine on up-regulation of cell surface voltage-dependent sodium channels in adrenal chromaffin cells

In cultured bovine adrenal chromaffin cells, (+/-)-bupivacaine inhibited veratridine-induced 22Na(+) influx (IC(50) 6.8 microM). The IC(50) of (+)-bupivacaine (2.8 microM) was 6.2-, 7.4-, and 17.1-fold lower than those of (-)-bupivacaine (17.3 microM), (-)-ropivacaine (20.6 microM), and lidocaine (47.8 microM). Chronic (i.e. 3-h) treatment of cells with (+/-)-bupivacaine increased cell surface [3H]saxitoxin ([3H]STX) binding capacity by 48% (EC(50) of 233 microM; t(1/2)=7.4 h), without changing the K(d) value. Treatment for 24 h with either (+)- or (-)-bupivacaine, or (-)-ropivacaine elevated [3H]STX binding, whereas 24-h treatment with lidocaine had no effect. The rise of [3H]STX binding by (+/-)-bupivacaine was prevented by cycloheximide, an inhibitor of protein synthesis, or brefeldin A, an inhibitor of cell surface vesicular exit from the trans-Golgi network; however, (+/-)-bupivacaine did not increase Na(+) channel alpha- and beta(1)-subunit mRNA levels. In cells subjected to (+/-)-bupivacaine treatment (1 mM for 24 h) followed by 3-h washout, veratridine-induced 22Na(+) influx was enhanced, even when measured in the presence of ouabain, an inhibitor of Na(+),K(+)-ATPase. Ptychodiscus brevis toxin-3 potentiated veratridine-induced 22Na(+) influx by 2.3-fold in the (+/-)-bupivacaine-treated cells, as in non-treated cells. These results suggest that lipophilic bupivacaine enantiomers or (-)-ropivacaine acutely inhibit Na(+) channel gating, whereas its chronic treatment up-regulates cell surface expression of Na(+) channels via translational and externalization events.     

Hepatocyte growth factor protects functional and histological disorders of HgCl(2)-induced acute renal failure mice

Hepatocyte growth factor (HGF) enhances proliferation of renal epithelial cells as well as hepatocytes. HGF accelerates recovery from acute renal failure (ARF) in animal models. However, pharmacological profiles of HGF including its action mechanism has not been studied in detail. An HgCl(2)-induced ARF mouse was used in this study to evaluate the efficacy of HGF. Single administrations of recombinant human HGF or vehicle were given to ARF mice 30 min after HgCl(2) injection. Renal function was monitored by measuring serum creatinine, blood urea nitrogen and creatinine clearance. In the ARF mice, there was a deterioration of renal function biochemical parameters and histological evidence of renal damage including acute tubular necrosis of proximal tubules. These were both significantly ameliorated by a single HGF administration. The effect of HGF was noticeable in the early phase of ARF (1 day after onset) when there was no histological evidence of increased labeling indexes in renal tubular epithelial cells. Western blot analysis of the c-Met/HGF receptor showed that tyrosine phosphorylation was enhanced immediately after HGF administration indicating direct activation of renal epithelial cells. HGF prevented increase of apoptotic nuclei with DNA fragmentation in renal epithelial cells which suggests cytoprotective activity of HGF on renal epithelial cells in the ARF mice.     

Malignant fibrous histiocytoma of perirenal tissue: a case report

A 75-year-old woman was admitted to our hospital with an extremely large retroperitoneal tumor that had been detected with ultrasound on a routine health check. She had no complaint except lumbar pain. Computed tomography revealed a heterogenous tumor located outside the right kidney which was enhanced gradually. Doppler ultrasound showed mild vascularity in the tumor. We performed tumorectomy and right nephrectomy because the tumor was adherent to the right kidney. The tumor was 16 x 11 x 7 cm in size and weighed 621 g. The histopathological diagnosis was malignant fibrous histiocytoma. The tumor was considered to have arisen from perirenal tissue.     

Identification of addicsin/GTRAP3-18 as a chronic morphine-augmented gene in amygdala

Using subtractive cloning, we identified a 1.4 kb mRNA that was ubiquitously expressed in various tissues; this mRNA was highly up-regulated in amygdala nuclei in mice when morphine was repeatedly administered but not when an opiate-receptor antagonist was co-administered. The mRNA encodes a 23 kDa protein, designated 'addicsin'. This contains two putative PKC-phosphorylation motifs and several hydrophobic regions, and was recovered in a soluble protein fraction of brain lysate. Its primary structure showed 98% identity with that of rat glutamate-transporter-associated protein 3-18 (GTRAP3-18), a putative modulator of neural glutamate-transporter EAAC1. Up-regulation of addicsin expression by morphine may affect glutamate uptake in the amygdala, causing mice to develop morphine tolerance and dependence.