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Biomedical subjects

M Konishi

Publications and source records attributed to M Konishi.

At least 37 records · Page 2Linked to original sources
PubMed2001

[Acute exacerbations due to Streptococcus pneumoniae in chronic lower respiratory tract infections during long-term macrolide therapy].

In Japan, long-term 14-membered macrolide administration is chosen as a first line therapy against chronic lower respiratory tract infections (CLRTIs) such as diffuse panbronchiolitis, bronchiectasis and chronic bronchitis. However, sometimes acute exacerbations occur in these cases, even if therapy is effective. We investigated 18 episodes of CLRTIs exacerbations that were caused by Streptococcus pneumoniae during long-term macrolides therapy from 1991 to 1999 to clarify the clinical features and prevalence of antimicrobial resistance in S. pneumoniae. Exacerbations did not occur only in winter season, but also in other seasons. Among 18 episodes of exacerbation, only 7 episodes (39%) revealed infiltration in chest roentogenogram and few episodes revealed marked elevations of inflammation markers in laboratory data. Intermediate resistance or resistance rates of S. pneumoniae isolated from sputum or transtracheal aspiration were 100% to erythromycin, 67% to clindamycin or minocycline, 11% to ampicillin, and 0% to cephazoline or imipenem. Coresistance to erythromycin, clindamycin and minocycline was seen in a half of the episodes. Resistance was not correlated with the duration of macrolides administration. All episodes were mainly treated with beta-lactam agents or fluoroquinolones and cured successfully. These findings suggest that acute exacerbations in CLRTIs caused by S. pneumoniae during long-term macrolides therapy do not reveal severe clinical aspects and can be treated successfully at present, but attention should be paid to the trend of antibiotic susceptibility in S. pneumoniae.

Adolescent↗
PubMed2001

[Pathogenetic study on bronchopulmonary infections in 1,416 patients by transtracheal aspiration method].

We have performed transtracheal aspiration (TTA) in 1,416 patients, who were suspected to have bronchopulmonary infection, in order to collect non-contaminated specimens directly from the lower airway. The overall isolation rates in 1,416 TTA were 68.7% for any microorganisms. Aerobes had a high incidence but many kinds of microorganisms were associated with bronchopulmonary infections. Haemophilus influenzae was the major pathogen in patients with acute bronchitis. Streptococcus pneumoniae was the most important pathogen and mycoplasma was often isolated in patients with community-acquired pneumonia. Major pathogens of nosocomial pneumonia consisted of alpha-streptococcus spp., anaerobes and Pseudomonas aeruginosa. Anaerobes were isolated from transtracheal aspirates in 20 of 33 episodes of lung abscesses. H. influenzae and P. aeruginosa were the main persistent pathogens and H. influenzae, S. pneumoniae and anaerobes were important exacerbated pathogens in patients with chronic lower respiratory tract infection. S. pneumoniae was isolated more from TTA than expectorated sputa. Oropharyngeal flora bacteria were easily isolated in the culture of expectorated sputa. We assessed the final diagnosis or causative factor in 443 patients whom no microorganism was isolated from transtracheal aspirates. The final diagnosis was infectious diseases in 52 patients (11.7%) and non-infectious diseases in 80 patients (18.1%), respectively. The causative factor was unsuited TTA sample in 81 patients (18.3%), preceding antimicrobial chemotherapy in 95 patients (21.4%) and unknown in 135 patients (30.5%), respectively. The pathogenesis of bronchopulmonary infections is complex and various microorganisms are associated with pathogens of bronchopulmonary infections. Therefore, we should accurately diagnose the pathogens in patients with bronchopulmonary infections. TTA is one of the useful methods that we can accurately detect the respiratory pathogens.

Adolescent↗
PubMed2001

Rat mannose-binding protein a binds CD14.

Lipopolysaccharide (LPS) has been known to induce inflammation by interacting with CD14, which serves as a receptor for LPS. Mannose-binding protein (MBP) belongs to the collectin subgroup of the C-type lectin superfamily, along with surfactant proteins SP-A and SP-D. We have recently demonstrated that SP-A modulates LPS-induced cellular responses by interaction with CD14 (H. Sano, H. Sohma, T. Muta, S. Nomura, D. R. Voelker, and Y. Kuroki, J. Immunol. 163:387-395, 2000) and that SP-D also interacts with CD14 (H. Sano, H. Chiba, D. Iwaki, H. Sohma, D. R. Voelker, and Y. Kuroki, J. Biol. Chem. 275:22442-22451, 2000). In this study, we examined whether MBP, a collectin highly homologous to SP-A and SP-D, could bind CD14. Recombinant rat MBP-A bound recombinant human soluble CD14 in a concentration-dependent manner. Its binding was not inhibited in the presence of excess mannose or EDTA. MBP-A bound deglycosylated CD14 treated with N-glycosidase F, neuraminidase, and O-glycosidase, indicating that MBP-A interacts with the peptide portion of CD14. Since LPS was also a ligand for the collectins, we compared the characteristics of binding of MBP-A to LPS with those of binding to CD14. MBP-A bound to lipid A from Salmonella enterica serovar Minnesota and rough LPS (S. enterica serovar Minnesota Re595 and Escherichia coli J5, Rc), but not to smooth LPS (E. coli O26:B6 and O111:B4). Unlike CD14 binding, EDTA and excess mannose attenuated the binding of MBP-A to rough LPS. From these results, we conclude that CD14 is a novel ligand for MBP-A and that MBP-A utilizes a different mechanism for CD14 recognition from that for LPS.

Animals↗
PubMed2001

Increased heat-escape/cold-seeking behavior following hypertonic saline injection in rats.

We examined the effect of hypertonic saline injection on heat-escape/cold-seeking behavior in desalivated rats. Rats were exposed to 40 degrees C heat after normal (154 mM NaCl, control) or hypertonic saline (2,500 mM NaCl) injection (1 ml/100 g body wt). The rats received a 0 degrees C air for 30 s when they entered a specific area in an experimental box. Core temperature (T(c)) surpassed 40 degrees C in both conditions when 0 degrees C air was not available. Hypertonic saline injection produced a lower baseline T(c) than control [36.9 +/- 0.2 and 37.9 +/- 0.2 degrees C (means +/- SE), P < 0.05] and a greater number of 0 degrees C air rewards during the 2-h heat with lower T(c) at the end (48 +/- 1 and 34 +/- 2, 37.6 +/- 0.1, and 37.3 +/- 0.1 degrees C in the control and hypertonic saline injection trial, respectively, P < 0.05, n = 6). However, T(c) was similar (37.7 +/- 0.2 and 37.6 +/- 0.4 degrees C in the control and hypertonic saline injection trial, n = 5) when 0 degrees C air was automatically and intermittently (35 times) given during the heat. Rats augment heat-defense mechanisms in response to osmotic stress by lowering the baseline T(c) and increasing heat-escape/cold-seeking behavior.

Animals↗
PubMed2001

Anti-cachectic effect of clarithromycin for patients with unresectable non-small cell lung cancer.

We have previously reported that long-term treatment with clarithromycin (CAM) increased the median survival of patients with non-small cell lung cancer, and improved various clinical parameters in these patients. In the present study, CAM was administered to 33 patients with unresectable primary non-small cell lung cancer, who had received chemotherapy, radiotherapy or both (basic cancer therapy). Patients with clinical backgrounds matched to the CAM group, who did not receive CAM treatment, were included into this study as a control group (non-CAM group). CAM treatment was initiated 4 weeks after the basic cancer therapy. The non-CAM group did not receive a placebo. Before and after the 3-month treatment with CAM, body weight, serum levels of interleukin-6 (IL-6, a cytokine which, together with TNF-alpha, plays a crucial role in the development of cancer cachexia), total protein, albumin, cholinesterase and hemoglobin were measured for the evaluation of the patients' clinical status. There were no statistically significant differences in serum levels of IL-6 between the CAM group before the treatment and the non-CAM group. After 3 months of CAM treatment, serum levels of IL-6 significantly decreased. In contrast, body weight, cholinesterase, and hemoglobin increased to a significant extent. Among these four parameters, however, the decrease in serum IL-6 levels was only statistically correlated with the increase in body weight, but not with that in other parameters. Furthermore, CAM-treated patients whose serum IL-6 levels were decreased after 3 months of treatment survived longer: there was a statistically significant correlation between the decrease in serum IL-6 and survival time. In contrast, in the non-CAM group, these parameters did not change significantly during the study. These results suggest that CAM may reduce the progression of cancer-associated cachexia.

Aged↗
PubMed2001

Overexpression of sialyl Lewis x antigen is associated with formation of extratumoral venous invasion and predicts postoperative development of massive hepatic metastasis in cases with pancreatic ductal adenocarcinoma.

The clinicopathological factors and expression of sialyl Lewis antigens which are the cell adhesion molecules to endothelial cells were compared in relation to the extent of the postoperative hepatic metastasis in 23 consecutive patients with pancreatic ductal adenocarcinoma whose clinical courses were carefully monitored and documented. The overall survival of cases with massive hepatic metastasis (MHM) was significantly poorer than that of those with local or no hepatic metastasis (p = 0.0453). Postoperative MHM was significantly correlated with the presence of duodenal invasion (p = 0.0418), the presence of portal vein invasion (p = 0.0435), the presence of extratumoral venous invasion (p = 0.0052) and high expression of sialyl Lewis x antigen (p = 0.0022). Multivariate analysis confined significant correlation between the high expression of sialyl Lewis x antigen and the development of MHM (p = 0.0402). Kaplan-Meier analysis revealed that the overall survival of patients with a high expression of sialyl Lewis x antigen was significantly poorer than that of patients with a low expression of the antigen (p = 0.0216). These results indicate that the overexpression of sialyl Lewis x antigen plays an important role in the development of MHM, and also predicts a poorer overall survival of these patients. Further studies with more cases are warranted to confirm these results.

Adult↗
PubMed2001

Cysteine proteinase gene expression in the endosperm of germinating carrot seeds.

A gene for carrot seed cysteine proteinase (CSCP; AB057371, AB057372) was cloned using PCR. The deduced amino acid sequence of CSCP had active sites for eukaryotic cysteine proteinases, putative signal sequences, and an endoplasmic reticulum targeting sequence. RNA gel blot analysis showed that CSCP transcripts appeared from dry seed, reached a maximum 3 days after imbibition (DAI), and disappeared by 5 DAI. In situ hybridization showed that CSCP transcripts accumulated in the endosperm of germinating seeds. This is the first report of the expression pattern of a cysteine proteinase gene in the endosperm of germinating dicotyledonous plants. The promoter of the CSCP gene had an endosperm motif and many other motifs also found in the promoters of endosperm-specific storage protein genes in monocotyledons. It is suggested that dicotyledons, like monocotyledons, have a temporal and spatial regulation system for endosperm-specific gene expression in germinating seeds.

Amino Acid Sequence↗
PubMed2001

Evaluation and application of liquid chromatographic columns coated with "intelligent" ligands. (III). Immobilized phospholipid column.

Immobilized enzyme columns have been developed for use as high-performance liquid chromatographic enzyme reactors. Enzyme reactors were prepared by immobilizing trypsin or cytochrome-c on phospholipid columns. Dynamic coating was employed to prepare the reactors by recycling a buffer solution containing trypsin or cytochrome-c through a phospholipid-coated column, on which the enzymes were immobilized by hydrophobic binding. The immobilized trypsin column displayed hydrolytic activity which catalyzed the hydrolysis of L-amino acid esters to amino acid. The immobilized cytochrome-c column exhibited oxidation activity which catalyzed N-demethylation of N,N-dimethylaniline, codeine, and dihydrocodeine in the presence of hydrogen peroxide as an oxygenating agent. The enzyme reaction proceeded rapidly in the column; both product and substrate could be separated and detected simultaneously. The immobilized enzyme columns could be readily regenerated using the original phospholipid column by repeating the dynamic coating. These immobilized enzyme columns could be utilized as enzyme reactors in the high-performance liquid chromatographic mode. Complete hydrolysis of amino acid ester was observed with the trypsin column. Demethylation of codeine and of dihydrocodeine were observed with the cytochrome-c column.

Aniline Compounds↗
PubMed2001

Calcium waves in skinned cardiac myocytes evoked by two-photon excitation photolysis of caged calcium.

In rat ventricular myocytes chemically skinned with saponin, a local rise of [Ca2+] was achieved by two-photon excitation photolysis (TPP) of the caged Ca2+ compound 1-(2-nitro-4,5-dimethoxyphenyl)-N,N,N',N'-tetrakis[(oxycarbonyl)methyl]-1,2-ethanediamine (DM-nitrophen). Confocal Ca2+ images, by use of fluo-3, were simultaneously collected. TPP of DM-nitrophen induced Ca2+ waves propagating over the myocyte, and the local rise of [Ca2+] at the site of photolysis sustained for 50-60 ms. These TPP-induced Ca2+ events were completely suppressed by ryanodine (10 microM), suggesting that Ca2+ release resulting from TPP of DM-nitrophen triggered regenerative Ca2+ release from the neighboring sarcoplasmic reticulum. The present techniques should be useful to investigate the interaction of elementary Ca2+ events, the process leading to global Ca2+ movements, in cardiac myocytes and other types of cells.

Animals↗
PubMed2001

Study design and organization of the JPHC study. Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases.

The Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases (JPHC Study; formerly called "Koseisho Multipurpose Prospective Cohort Study") began in 1990 (Cohort I) and 1993 (Cohort II). The JPHC Study covers 11 public health center areas throughout Japan and includes a total of 140,420 residents. The study's design includes a baseline survey with a self-administered questionnaire on lifestyle and collection of blood and health checkup data; a follow-up system for mortality, migration, and incidence of cancer and cardiovascular diseases; an additional follow-up survey after 5 and 10 years; and distribution of a newsletter. The JPHC study is expected to provide evidence for the prevention and control of cancer and cardiovascular diseases in the 21st century.

Adult↗
PubMed2001

Health status, life habits, and social background among the JPHC study participants at baseline survey. Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases.

A self-reported questionnaire on the health status, life habits, and social background was conducted at baseline in the Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases (JPHC study). This report presents the outcome of the study regarding past or family history of various diseases, medical treatment, life habits such as physical labor or sports, and social background among study participants. In both cohorts I and II, prevalent past and family history included hypertension, stroke, and cancer, whereas the prevalence of coronary heart diseases was historically low. The prevalence of a past history of hypertension and stroke was higher in the northern part of Japan, Ninohe, and Yokote, and lower in Okinawa, compared to the other districts. The prevalence of participants with a history of stomach cancer and liver cancer was higher in Arikawa than in other districts. The frequency of participants who took medication from doctors ranged from 20% to 30%, higher in the Tohoku areas, and lower in Okinawa compared to the other districts. All districts showed a high rate of over 70% for the participation rate for basic health examination conducted by the local government, The rate was particularly high in the Tohoku area where a high prevalence of a history of hypertension was found. The frequency of persons who had a chance to participate in sports or physical exercise was high in Okinawa and Suita subcohort 2, although the mean total physical activity (both at work and for leisure time) was lowest in the latter subcohort. No substantial differences were found in compositions of personality among districts. The frequency of more active and positive persons, however, was relatively higher in urban areas and lower in Okinawa compared to the other districts. The association between the differences of health status, life habits, and social background and the occurrence of various lifestyle-related diseases will be clarified in a follow-up study within the JPHC study.

Adult↗
PubMed2001

Anthropometric measures, blood pressure and major laboratory examination results in the health check-up examination among the JPHC study participants at baseline survey. Japan Public Health Center-based Prospective Study on Cancer and Cardiovascular Diseases.

Health check-up data were compared in all 11 populations included in the cohort. The collected sample size was 23,313 in Cohort I and 24,654 in Cohort II. Height was greater in two urban populations, and body mass index (BMI) was largest in the two populations in Okinawa prefecture. Blood pressure was higher in the populations in northeast part of Japan and Okinawa prefecture, and lower in Suita. Serum total cholesterol level was higher in Okinawa and two urban populations, and lower in the populations in northeast part of Japan, and in Arikawa and Saku.

Adult↗
PubMed2001

Spread of Ca2+ in the sarcomere during fast and slow activation of mammalian cardiac myocytes.

A multi-compartment model was used to estimate Ca2+ gradients in a sarcomere of a cardiac myocyte. The mathematical model assumed Ca2+ release from the sarcoplasmic reticulum as a driving function, and calculated Ca2+ binding to myoplasmic buffers, Ca2+ uptake by the sarcoplasmic reticulum, and diffusion of Ca2+ (and the buffers). During the fast Ca2+ transient similar to those observed during a twitch, the model predicted a large Ca2+ gradient in the sarcomere. A trajectory of the instantaneous relation between spatially averaged concentrations of Ca2+ and the Ca2+-troponin complex showed a counterclockwise loop, indicating non-equilibrium Ca2+ binding to troponin. During slow changes in [Ca2+] with time to peaks of approximately 500 ms or longer, the gradient of [Ca2+] was largely dissipated and the apparent equilibrium of the Ca2+-troponin binding reaction was suggested with little hysteresis of the trajectory. We conclude that a steady-state relation between [Ca2+] and mechanical activity can be achieved uniformly in the sarcomere by slowing the rate of Ca2+ release from the sarcoplasmic reticulum.

Algorithms↗
PubMed2001

The effect of anabolic steroid on the distribution of muscle fiber in rat hind limb.

This study evaluates the effect of anabolic steroid hormone (nandrolone decanoate, 19-Nortestosterone; ND) on histomorphometry and distribution of muscle fiber in the rat tibialis anterior (TA) muscle compared with the control rats. Three male Wistar rats aged of 5 weeks were daily received subcutaneous injection of 0.3 cc vehicle oil included 1mg ND for 6 weeks. Two control (C) rats were done only vehicle oil by the same manner as the experimental (E) group. The TA muscle was stained for myofibrillar adenosine triphosphatease with preincubation at pH 4.35, after cryosectioning at the thickness of 10 microm. Muscle fibers were classified into type I, IIA, IIX, and IIB. The E group showed significantly smaller than the C group in body weight. In histomorphometry, the cross-sectional area of type IIB fibers in the E group showed narrow range, and shifted smaller than those in the C groups. The distribution of type I fibers was restricted to the deep region in the E group. The anabolic steroid facilitated toward the older rat type on distribution and proportion of muscular tissue.

Aging↗
PubMed2000

Auditory neuroscience: development, transduction, and integration.

Hearing underlies our ability to locate sound sources in the environment, our appreciation of music, and our ability to communicate. Participants in the National Academy of Sciences colloquium on Auditory Neuroscience: Development, Transduction, and Integration presented research results bearing on four key issues in auditory research. How does the complex inner ear develop? How does the cochlea transduce sounds into electrical signals? How does the brain's ability to compute the location of a sound source develop? How does the forebrain analyze complex sounds, particularly species-specific communications? This article provides an introduction to the papers stemming from the meeting.

Animals↗
PubMed2000

Cellular mechanisms for resolving phase ambiguity in the owl's inferior colliculus.

Both mammals and birds use the interaural time difference (ITD) for localization of sound in the horizontal plane. They may localize either real or phantom sound sources, when the signal consists of a narrow frequency band. This ambiguity does not occur with broadband signals. A plot of impulse rates or amplitude of excitatory postsynaptic potentials against ITDs (ITD curve) consists of peaks and troughs. In the external nucleus (ICX) of the owl's inferior colliculus, ITD curves show multiple peaks when the signal is narrow-band, such as tones. Of these peaks, one occurs at ITDi, which is independent of frequency, and others at ITDi +/- T, where T is the tonal period. The ITD curve of the same neuron shows a large peak (main peak) at ITDi and no or small peaks (side peaks) at ITDi +/- T, when the signal is broadband. ITD curves for postsynaptic potentials indicate that ICX neurons integrate the results of binaural cross-correlation in different frequency bands. However, the difference between the main and side peaks is small. ICX neurons further enhance this difference in the process of converting membrane potentials to impulse rates. Inhibition also appears to augment the difference between the main and side peaks.

Acoustic Stimulation↗
PubMed2000

Brain-specific expression of a novel human UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferase (GalNAc-T9).

We isolated cDNA coding for the ninth of the UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (GalNAc-T9) from human brain by the polymerase chain reaction. The polypeptide encoded by GalNAc-T9 contained the structural features characteristic of GalNAc transferases, such as a GT1 motif, a Gal/GalNAc transferase motif, (QXW)(3) repeats, and conserved His, Cys, and acidic amino acid residues. Northern blot analysis revealed the mRNA expression of the enzyme to be confined to the brain. The brain-specific expression of GalNAc-T9 suggested that this isozyme catalyzes O-glycosylation in the brain.

Amino Acid Sequence↗