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%).     

Engraftment of sorted/expanded human central nervous system stem cells from fetal brain

Direct isolation of human central nervous system stem cells (CNS-SC) based on cell surface markers yields a highly purified stem cell population that can extensively expand in vitro and exhibit multilineage differentiation potential both in vitro and in vivo. The CNS-SC were isolated from fetal brain tissue using the cell surface markers CD133(+), CD34(-), CD45(-), and CD24(-/lo) (CD133(+) cells). Fluorescence-activated cell sorted (FACS) CD133(+) cells continue to expand exponentially as neurospheres while retaining multipotential differentiation capacity for >10 passages. CD133(-), CD34(-), and CD45(-) sorted cells (approximately 95% of total fetal brain tissue) fail to initiate neurospheres. Neurosphere cells transplanted into neonatal immunodeficient NOD-SCID mice proliferated, migrated, and differentiated in a site-specific manner. However, it has been difficult to evaluate human cell engraftment, because many of the available monoclonal antibodies against neural cells (beta-tubulin III and glial fibrillary acidic protein) are not species specific. To trace the progeny of human cells after transplantation, CD133(+)-derived neurosphere cells were transduced with lentiviral vectors containing enhanced green fluorescent protein (eGFP) expressed downstream of the phosphoglycerate kinase promoter. After transduction, GFP(+) cells were enriched by FACS, expanded, and transplanted into the lateral ventricular space of neonatal immunodeficient NOD-SCID brain. The progeny of transplanted cells were detected by either GFP fluorescence or antibody against GFP. GFP(+) cells were present in the subventricular zone-rostral migrating stream, olfactory bulb, and hippocampus as well as nonneurogenic sites, such as cerebellum, cerebral cortex, and striatum. Antibody against GFP revealed that some of the cells displayed differentiating dendrites and processes with neurons or glia cells. Thus, marking human CNS-SC with reporter genes introduced by lentiviral vectors is a useful tool with which to characterize migration and differentiation of human cells in this mouse transplantation model.     

Functional MRI of motor sequence acquisition: effects of learning stage and performance

Neural networks of motor control are well understood and the motor domain therefore lends itself to the study of learning. Neuroimaging of motor learning has demonstrated fronto-parietal, subcortical, and cerebellar involvement. However, there is conflicting evidence on the specific functional contributions of individual regions and their relative importance for early and advanced stages of learning. Using functional MRI (fMRI), we examined hemodynamic effects in seven right-handed men during brief episodes of explicit learning of novel six-digit sequences (experiments 1 and 2) and during prolonged learning of an eight-digit sequence (experiment 3), all performed with the dominant hand. Brief episodes of new learning were predominantly associated with bilateral activations in premotor and supplementary motor areas, superior and inferior parietal cortices, and anterior cerebellum. In experiment 2, which included a control condition matched for complexity of motor execution, we also found unexpectedly strong activation in the bilateral inferior frontal lobes. In experiment 3, analysis of task by learning stage interactions showed greater involvement of the bilateral superior parietal lobes, the right middle frontal gyrus, and the left caudate nucleus during early stages, whereas left occipito-temporal and superior frontal cortex as well as the bilateral parahippocampal region were more activated during late learning stages. Analysis of task by performance interactions (based on each subject's response times and accuracy during each scan) showed effects in bilateral fronto-polar, right hippocampal, and anterior cerebellar regions associated with high levels of performance, as well as inverse effects in bilateral occipito-parietal regions. We conclude that superior parietal and occipital regions are most intensely involved in visually driven explicit digit sequence learning during early stages and low performance, whereas later stages of acquisition and higher levels of performance are characterized by stronger recruitment of prefrontal and mediotemporal regions.     

Memory and learning-enhancing effect of Daikenchuto, a traditional Japanese herbal medicine, in mice

The effect of Daikenchuto (DKT), a traditional Japanese herbal medicine (Kampo medicine), and its constituents (ginger rhizome, ginseng root, rice gluten and Zanthoxylum fruit) on the memory formation process was examined in mice by means of a Morris water maze test. The administration of DKT [300–4000 mg/kg, administered orally (p.o.)] for 3 consecutive days dose-dependently shortened the time required by the mice to find the platform in the water maze test relative to the control. Among the four constituents of DKT, the extract of Zanthoxylum fruit (70 mg/kg, the dose equivalent to 4000 mg/kg DKT) administered p.o. for 3 consecutive days significantly promoted the memory and learning rate. The memory- and learning-enhancing effect was potently elicited by 5 mg/kg (p.o., 2 days) hydroxy-sanshool, the active component of the ethyl acetate fraction of Zanthoxylum fruit. In another series of experiments with the water maze test, the administration of scopolamine [1 mg/kg, intraperitoneally (i.p.)] for 3 consecutive days significantly prolonged the time needed by the mice to find the platform. The subsequent administration of DKT (4000 mg/kg, p.o.) for 3 consecutive days possessed an abatement effect on the scopolamine-induced dementia. The present results indicate that DKT and, more specifically, its constituent Zanthoxylum fruit and the active component of Zanthoxylum fruit, hydroxy-sanshool, all have a memory- and learning-enhancing effect and are probably associated with the release of acetylcholine from neuronal terminals in the brain.     

Trial of in vitro fertilization via epididymal duct aspirated sperm]

We made a trial of our method by which sperm are collected directly from epididymal duct, then subjected to in vitro fertilization. The subjects were a total of 22 cases comprising 14 of obstructed azoospermia and 8 of severe oligoasthenozoospermia, on which the surgery was performed 26 times. Using the microscope, an epididymal duct was directly punctured to make a suction of the fluid or was slightly incised to make a suction of the outflow. Sperms thus collected were preincubated for 4 to 6 hours, then subjected to in vitro fertilization. Condition of collected sperms; 32 x 10(4)-15300 x 10(4) sperms were obtained in real number. Sperm motility rate was 0-82%, averaging 25.0%. Sperm forward motility were fairly good in 18 of 26 test cases. Sperm condition was so poor as to make the insemination impossible in 4 test cases (16%). Fertility rate for cases of obstructed azoospermia was 53% (8/15 test cases) and 63% (55/87 eggs) in the test cases and the number of eggs, respectively, compared with 33% (2/6 test cases) and 5.4% (2/37 eggs), respectively for cases of oligo-asthenozoospermia. Pregnancy; Successful pregnancy was obtained in 2 of the cases of obstructed azoospermia, in each of which sperms were collected from the head of the epididymis, then passed into the maternal body by zygote intra fallopian tubal transfer (ZIFT); with the one case resulting in uneventful delivery in November 1991 and the other in a miscarriage. The above results suggested the present method would become an epoch-making approach in the treatment of severe male infertility.     

Observations of muscle plasma membrane undercoats in Duchenne and fukuyama muscula dystrophies

Muscle plasma membrane undercoats were investigated by conventional electron microscopy in both Duchenne muscular dystrophy (DMD) and Fukuyama congenital muscular dystrophy (FCMD). The densities of the plasma membrane undercoats were rarefied in the parts of the plasma membranes overlying the degenerating focus in both DMD and FCMD myofibers. The degree of rarefaction tended to be parallel to the degree of degeneration in the myofibers. It was hard to distinguish the undercoat densities of normal-looking myofibers of DMD and FCMD muscles from those of control myofibers from histochemically-normal muscles. On the other hand, the undercoats of regenerating myofibers in DMD and FCMD muscles were denser than normal.     

Autoradiographic study on the distribution of thymus-derived and thymus-independent lymphocytes in the spleen of Xenopus laevis

Non-thymectomized and early-thymectomized Xenopus laevis were injected with ³H-thymidine, and labelled lymphocytes from thymus, spleen, and peripheral blood were transferred to histocompatible recipients to study their distribution by autoradiography. An extremely high proportion of labelled thymocytes was localized in the splenic red pulp of both non-thymectomized and thymectomized recipients after transfer. Labelled splenic lymphocytes were localized in a significantly higher density in the splenic white- than red pulp, particularly 24 hr after cell transfer. This preference of labelled lymphocytes in the white pulp was more evident when early-thymectomized toads were used as lymphocyte donors. These results strongly suggest that in Xenopus, thymus-independent lymphocytes preferentially localize in the splenic white pulp, and thymus-derived lymphocytes possibly in the red pulp.     

Activation of human SII cortex during exploratory finger movement and hand clenching tasks

We used electric median nerve stimuli to elucidate the functional properties of neurons in the human secondary somatosensory cortex during exploration of small objects and muscle contraction. Somatosensory evoked fields were recorded from nine healthy subjects with a 204-channel neuromagnetometer. Electrical stimuli were applied once every 3 s to the left median nerve at the wrist. The conditions during the stimulation were rest (control session), exploration of small objects (exploration session) and clenching the hand while the wrist was being electrically stimulated (clench session). The strengths of equivalent current dipoles of evoked fields from the secondary somatosensory cortex were increased during the exploration session, but those of evoked fields were decreased by the clench session.