Tumour necrosis factor and lymphotoxin A polymorphisms and lung function in smokers

Genetic variants in the tumour necrosis factor (TNF) gene have been investigated in chronic obstructive pulmonary disease (COPD). However, there are many instances of nonreplication of these associations due to insufficient power or other factors. In this study, a large number of subjects were examined to elucidate whether genetic variations of TNF and/or lymphotoxin A (LTA), which is clustered with TNF, are associated with variations in lung function among smokers. The present authors designed two nested case-control studies in the National Heart, Lung, and Blood Institute Lung Health Study (LHS), which enrolled 5,887 smokers. The first design included continuous smokers who had the fastest (n = 279) and the slowest (n = 304) decline of lung function during the 5-yr follow-up period, and the second included the subjects who had the lowest (n = 533) and the highest (n = 532) post-bronchodilator % predicted forced expiratory volume in one second at the start of the LHS. Within the TNF and LTA region, 10 tagging single-nucleotide polymorphisms were selected and genotyped. Unlike the previous associations between TNF-308 and COPD in Asians, the current study found no association between either of the two phenotypes and the LTA and TNF polymorphisms. In conclusion, these results support the findings of previous studies in late-onset chronic obstructive pulmonary disease in Caucasian populations.

Involvement of IL-32 in activation-induced cell death in T cells

NK cell transcript 4 (NK4), now denoted as IL-32, was originally identified as a transcript whose expression was increased in activated NK cells. It has been very recently demonstrated that NK4 is secreted from several cells upon the stimulation of some inflammatory cytokines such as IL-18, IL-1beta, IFN-gamma and IL-12. Furthermore, NK4 induces production of tumor necrosis factor, macrophage inflammatory protein (MIP)-2 and IL-8 in monocytic cell lines, indicating that this factor would be involved in the inflammatory responses. Based on these findings, NK4 was renamed IL-32. However, the biological activities of IL-32 on other cell types remained undetermined. Furthermore, it was still argued whether IL-32 acts on cells from outside or inside the cells. In this article, we first report that expression of IL-32 was up-regulated in activated T cells and NK cells, and that IL-32beta was the predominantly expressed isoform in activated T cells. IL-32 was specifically expressed in T cells undergoing apoptosis and enforced expression of IL-32-induced apoptosis, whereas its down-regulation rescued the cells from apoptosis in HeLa cells. IL-32 existing in the supernatant would be derived from the cytoplasm of apoptotic cells. These results strongly indicated that IL-32 would be involved in activation-induced cell death in T cells, probably via its intracellular actions. Our present findings expand our understanding of the biological function of IL-32 and argue that IL-32 may act on cells, not only from the outside but also from the inside.

Induction and activation of the aryl hydrocarbon receptor by IL-4 in B cells

It is widely known that IL-4 and IL-13 act on various kinds of cells, including B cells, resulting in enhancement of proliferation, class switching to IgE and expression of several surface proteins. These functions are important for the recognition of the various antigens in B cells and are known to be involved in the pathogenesis of allergic diseases. However, it has not been known whether IL-4/IL-13 is involved in the metabolism of various kinds of xenobiotics including 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD), and it remains undetermined whether TCDD, an environmental pollutant, influences IgE production in B cells, exaggerating allergic reactions. We identified IL-4- or IL-13-inducible genes in a human Burkitt lymphoma cell line, DND-39, using microarray technology, in which the AHR gene was included. The AHR gene product, the aryl hydrocarbon receptor (AhR), was induced by IL-4 in both mouse and human B cells in a STAT6-dependent manner. IL-4 alone had the ability to translocate the induced AhR to the nuclei. TCDD, a ligand for AhR, rapidly degraded the induced AhR by the proteasomal pathway, although IL-4-activated AhR sustained its expression. AhR activated by IL-4 caused expression of a xenobiotic-metabolizing gene, CYP1A1, and TCDD synergistically acted on the induction of this gene by IL-4. However, the induction of AhR had no effect on IgE synthesis or CD23 expression. These results indicate that the metabolism of xenobiotics would be a novel biological function of IL-4 and IL-13 in B cells, whereas TCDD is not involved in IgE synthesis in B cells.

Characterization of the interaction between interleukin-13 and interleukin-13 receptors

Interleukin-13 (IL-13) possesses two types of receptor: the heterodimer, composed of the IL-13Ralpha1 chain (IL-13Ralpha1) and the IL-4Ralpha chain (IL-4Ralpha), transducing the IL-13 signals; and the IL-13Ralpha2 chain (IL-13Ralpha2), acting as a nonsignaling "decoy" receptor. Extracellular portions of both IL-13Ralpha1 and IL-13Ralpha2 are composed of three fibronectin type III domains, D1, D2, and D3, of which the last two comprise the cytokine receptor homology modules (CRHs), a common structure of the class I cytokine receptor superfamily. Thus far, there has been no information about the critical amino acids of the CRHs or the role of the D1 domains of IL-13Ralpha1 and IL-13Ralpha2 in binding to IL-13. In this study, we first built the homology modeling of the IL-13.hIL-13 receptor complexes and then predicted the amino acids involved in binding to IL-13. By incorporating mutations into these amino acids, we identified Tyr-207, Asp-271, Tyr-315, and Asp-318 in the CRH of human IL-13Ralpha2, and Leu-319 and Tyr-321 in the CRH of human IL-13Ralpha1, as critical residues for binding to IL-13. Tyr-315 in IL-13Ralpha2 and Leu-319 in IL-13Ralpha1 are positionally conserved hydrophobic amino acid residues. Furthermore, by using D1 domain-deleted mutants, we found that the D1 domain is needed for the expression of IL-13Ralpha2, but not IL-13Ralpha1, and that the D1 domain of IL-13Ralpha1 is important for binding to IL-13, but not to IL-4. These results provide the basis for a precise understanding of the interaction between IL-13 and its receptors.

Crisis-induced intermittency in two coupled chaotic maps: towards understanding chaotic itinerancy

The present paper considers crisis-induced intermittency in a system composed of two coupled logistic maps. Its purpose is to clarify a bifurcation scenario generating such intermittent behaviors that can be regarded as a simple example of chaotic itinerancy. The intermittent dynamics appears immediately after an attractor-merging crisis of two off-diagonal chaotic attractors in a symmetrically coupled system. The scenario for the crisis is investigated through analyses of sequential bifurcations leading to the two chaotic attractors and successive changes in basin structures with variation of a system parameter. The successive changes of the basins are also characterized by variation of a dimension of a fractal basin boundary. A numerical analysis shows that simultaneous contacts between the attractors and the fractal basin boundary bring about the crisis and a snap-back repeller generated at the crisis produces the intermittent transitions. Furthermore, a modified scenario for intermittent behaviors in an asymmetrically coupled system is also discussed.

Expression of glucose transporter 5 by microglia in human gliomas

Our previous studies indicate that glucose transporter 5 (GLUT5) is a microglial marker in routine paraffin sections, and is rarely present in monocytes/macrophages of the peripheral organs. We examined the expression of GLUT5 in 91 cases of human gliomas to characterize the microglial phenotype in glioma tissues. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded sections using such antibodies as a GLUT5 antibody, two markers for activated microglia: major histocompatibility complex (MHC) class II Ag and macrophage scavenger receptor class A (MSR-A), and MIB-1 antibody. The immunoreactivity of GLUT5 was present in three microglial phenotypes: ramified (resting), activated, and ameboid (macrophagic) microglia in most of the cases. A double-labelling study of astrocytic tumours using GLUT5 and MIB-1 antibodies demonstrated a proportion of proliferating microglia. However, no morphological difference between MIB-1-positive, microglial cells and MIB-1-negative, microglial cells was found. The number of GLUT5-positive microglia was significantly (P < 0.001) higher in astrocytic tumours than in oligodendroglial tumours. Many GLUT5-positive microglia (up to 52% in total cells) were often observed in pilocytic astrocytomas, where microglial cells were predominantly ramified, and the number of MHC class II- or MSR-A-positive microglia was less than GLUT5-positive microglia. Thus, the present study indicated that intrinsic microglia can be a source of microglia/macrophages cell populations in astrocytic tumours, and that pilocytic astrocytomas often have a high proportion of microglial cells with mild activation.

Novel crystalloid structures in suprasellar paraganglioma

A-52-year-old woman was admitted to a hospital because of 2-year history of abnormal behavior and impaired visual acuity. Magnetic resonance imaging delineated a sizable mass at the suprasellar region. The partially removed tumor was arranged in irregular lobules composed of an admixture of clusters of cobblestone-like small cells and process-bearing cells with ovoid nuclei, surrounded by a fine, neuropil-like matrix. The Zellballen structure was inconspicuous, and mitosis was absent. Immunohistochemically, the tumor cells were positive for chromogranin A, synaptophysin, class III beta-tubulin and neurofilament, while negative for glial fibrillary acidic protein, cytokeratin and all 6 pituitary hormones. S100 protein expression was limited to cells adjacent to stroma. The MIB-1 labeling index was 0.5%. Histopathological diagnosis was paraganglioma of abortive architecture. Ultrastructurally, numerous dense-cored vesicles were found within the processes and cytoplasm. Synapse formation was not demonstrated. Interestingly, crystalloids up to 3 microm in size were frequently found. They had hexagonal or quadrilateral architecture without limiting membranes. The interval between periodically arranged fibrils was variable, ranging from approximately 20 - 50 nm. Retrospective examination by light microscopy failed to reveal corresponding structures. Crystalloids are rare manifestation of paragangliomas, yet undescribed in those of intracranial origin. Furthermore, the ultrastructure of the present case differs from those of previous cases.

[Liposarcoma of the pleural cavity; report of a case]

A 43-year-old-woman who had sever anterior chest pain visited our hospital on April 3, 2000. A well-defined abnormal shadow was seen in the middle and lower field of the right lung on chest X-ray. Computed tomography showed a large fat density mass in the right pleural cavity with a septum enhanced by contrast medium. Percutaneous needle biopsy revealed lipoma or liposarcoma. Complete resection could be done with combined resection of right lung, lpericardium, parietal pleura and diaphragm. Final histologic diagnosis was well differentiated liposarcoma. There are few reports of liposarcoma arising in the thoracic cavity, we present our case and review the 23 cases reported from the Japanese literatures.

Randomized study of dose or schedule modification of granulocyte colony-stimulating factor in platinum-based chemotherapy for elderly patients with lung cancer

It is generally believed that elderly patients are less able to tolerate aggressive cancer chemotherapy than their younger counterparts. Bone marrow cellularity diminishes with age and elderly patients may have decreased tolerance to myelosuppressive agents. Between November 1995 and October 1999, 68 chemotherapy-naive elderly (70 or more years old) patients with histologically or cytologically proven lung cancer who were to receive platinum-based chemotherapy were enrolled in this study. All patients had adequate cardiac, hematological, liver and renal function to receive chemotherapy. Patients were randomized into 3 groups. Patients in groups 1 and 2 received 2 microg/kg and 4 microg/kg granulocyte colony-stimulating factor (G-CSF, lenograstim), respectively, when grade 3 leukopenia (<2,000/microl) or neutropenia (<1,000/microl) appeared after chemotherapy. Patients in group 3 received 2 microg/kg G-CSF when grade 2 leukopenia (<3,000/microl) or neutropenia (<1,500/microl) appeared after chemotherapy. G-CSF was stopped in all groups when the leukocyte count increased to over 10,000/microl or the neutrophil count exceeded 5,000/microl. Full blood cell counts were examined 3 times a week after chemotherapy. All patients received platinum-based chemotherapy. Eighteen, 16 and 22 patients (78%, 73% and 96%) in groups 1, 2 and 3, respectively, received G-CSF when leukopenia or neutropenia appeared. The durations of G-CSF treatment required by groups 1 and 3 (5.7+/-3.6 and 6.6+/-3.2 days, respectively) did not differ significantly, but the duration of treatment required by group 2 (3.7+/-2.8 days) was significantly shorter than that of group 1 (p=0.048). The duration of grade 4 neutropenia in group 2 (0.7+/-1.1 days) was marginally shorter than that in group 1 (1.6+/-2.1 days, p=0.076). The neutrophil nadir of group 2 (949+/-757/microl) was marginally higher than that of group 1 (592+/-438/microl, p=0.058). No patients in group 2 experienced grade 4 neutropenia for 4 days or more or a neutrophil nadir less than 100/microl a significant difference from group 1, where 22% and 17% of patients experienced these events (p=0.02 and p=0.04, respectively). Similarly, no infections requiring antibiotics after chemotherapy occurred in patients in group 2, a significant difference from group 1 (26%, p=0.01). The rates of neutropenia and infection in groups 1 and 3 did not differ significantly. The peak plasma concentration of G-CSF in group 2 was significantly higher than in group 1 (p=0.0018), but did not differ significantly between groups 1 and 3. Doubling the dose of G-CSF could help to decrease neutropenia and prevent infection after chemotherapy in elderly patients with lung cancer.

Normalized pulse volume (NPV) derived photo-plethysmographically as a more valid measure of the finger vascular tone

Normalized pulse volume (NPV) was advocated as a more valid measure for the assessment of finger vascular tone. Based on the optical model in the finger tip expressed by Lambert--Beer's law, NPV is expressed as Delta I(a)/I. Here, Delta I(a) is the intensity of pulsatile component superimposed on the transmitted light (I). Theoretically, NPV seems to be superior to the conventional pulse volume (PV; corresponding to Delta I(a)). Firstly, NPV is in direct proportion to Delta V(a), which is the pulsatile component of the arterial blood volume, in a more exact manner. Relatedly, NPV can be processed as if it is an absolute value. Secondly, the sensitivity of NPV during stressful stimulations is expected to be higher. These expectations were supported experimentally using 13 male students. Firstly, the correlation between cutaneous vascular resistance in the finger tip (CVR) and NPV was higher than that between CVR and PV among all the subjects, although there was not much difference between these correlations within each subject. Secondly, NPV decreased much more than PV during mental stress. Some limitations of the present study were addressed, including the point that certain factors can violate the direct proportional relationship of NPV and PV to Delta V(a).

Diastolic flow velocity of the left pulmonary artery of patent ductus arteriosus in preterm infants

BACKGROUND

The usefulness of diastolic pulmonary flow velocity determined by echocardiography in the assessment of symptomatic patent ductus arteriosus (sPDA) in preterm infants has not been confirmed.

METHODS

Echocardiography was performed daily in infants ranging from 23 to 31 gestational weeks of age, and diastolic flow velocity of the left pulmonary artery (DFLPA) was measured. The DFLPA data before indomethacin administration for sPDA were compared with data obtained after indomethacin administration. The normal range of DFLPA was also determined from serial measurements performed in infants who did not develop sPDA during the first 7 days of life. Then, this range was compared with data from infants who did develop sPDA during this time.

RESULTS

In infants who underwent indomethacin treatment, DFLPA increased with the development of sPDA and decreased when the symptoms of sPDA disappeared. On the basis of results from serial DFLPA measurement, the sensitivity and specificity of DFLPA for assessing sPDA was found to be 0.82 and 0.83, respectively.

CONCLUSIONS

Measurement of DFLPA by echocardiography is a useful method for assessing sPDA in preterm infants.

Increased expression levels of p53 correlate with good response to cisplatin-based chemotherapy in non-small cell lung cancer

In order to determine whether expression of the tumor suppressor gene p53 in non-small cell lung cancer (NSCLC) correlates with chemotherapeutic response, resected tumors from 18 patients with recurrent lung cancer who had undergone complete resection and received chemotherapy after the initial tumor recurrence were subjected to p53 immunostaining. Histological examination of the resected tumors revealed 11 adenocarcinomas, 6 squamous cell carcinomas and one adenosquamous cell carcinoma. Group 1 was </=50% (n=9) and group 2 >50% (n=9) p53-immunopositive. All patients received cisplatin-based chemotherapy after recurrence. No patient in group 1 achieved response to chemotherapy whereas 2 and 3 in group 2 achieved complete and partial responses, respectively. The chemotherapy response rate of group 2 (56%) was significantly higher than that of group 1 (0%, p=0.009). The times to reoccurrence after tumor resection of group 2 was significantly better than that of group 1 (log-rank p=0.019, Wilcoxon p=0.042), and survival after chemotherapy of group 2 was also significantly better than that of group 1 (log-rank p=0.023, Wilcoxon p=0.034). It is suggested that high p53 expression levels in tumors correlate with both good response to cisplatin-based chemotherapy and good survival of patients with advanced NSCLC.

Role of infection in the development of acquired subglottic stenosis in neonates with prolonged intubation

OBJECTIVE

To examine whether clinically diagnosed infection correlates with subsequent development of subglottic stenosis in intubated neonates.

METHODS

Sixty-two neonatal infants intubated for more than 14 days were examined. Several risk factors for subglottic stenosis, including infection, duration of intubation, frequency of intubation, the size of the endotracheal tube etc., were evaluated by multiple logistic regression analysis.

RESULTS

Infection that occurred within 14 days of intubation showed a positive correlation with subsequent subglottic stenosis. The duration of intubation, frequency of intubation and the size of the endotracheal tube did not affect the development of subglottic stenosis. The majority of infections were considered to be respiratory tract infections, including pneumonia.

CONCLUSIONS

Infection occurring within 14 days of intubation is considered to be a risk factor for acquired subglottic stenosis in neonates intubated for more than 14 days. Prevention of infection within 14 days of intubation may reduce the incidence of subglottic stenosis in neonates.

[A case of mixed connective tissue disease with lupus-like manifestations of the central nervous system, successfully treated with cyclophosphamide combined with prednisolone]

A 29-year-old woman experienced Raynaud's phenomenon, swelling of her fingers, eruptions on her face, and muscle weakness in 1990. She was diagnosed as having mixed connective tissue disease (MCTD) and was treated with prednisolone (PSL) for 3 years. Most of her complaints disappeared after the treatment. In March 1997, she experienced fever, erythema, and lymphadenopathy. Although she was treated with PSL (20 mg/day) again, muscle weakness, mental disturbance, and recto-urinary disturbance appeared. When she was re-admitted to our hospital, increased levels of muscle-derived enzymes and positivity of anti-RNP antibody were found. High signal areas in her cerebrum were shown by magnetic resonance imaging, and slow and spike pattern was shown by electroencephalography. Hypoperfusion of the cerebral blood flow was suggested on single photon emission computed tomography. The number of mononuclear cells, amount of protein and level of interleukin-6 were found to be elevated in her cerebrospinal fluid (CSF). Her neurological manifestations were diagnosed as being due to MCTD, and showed characteristics similar to those of systemic lupus erythematosus. She was treated with PSL (60 mg/day) followed by steroid pulse therapy. Because the response to this treatment was partial, oral administration of cyclophosphamide (CPM) (100 mg/day) was added. Muscle weakness and neurological abnormalities as well as abnormal laboratory findings gradually improved over the following two months. We conclude that the treatment with CPM combined with PSL may be useful, when neurological manifestations of MCTD are serious and resistant to conventional therapy.

Prophylactic administration of granulocyte colony-stimulating factor when monocytopenia appears lessens neutropenia caused by chemotherapy for lung cancer

In a retrospective study, we showed that a monocyte count of <150/microl on days 6 to 8 might be a predictor of grade III or IV neutropenia during cancer chemotherapy given at 3- or 4-week intervals. In the present study, we investigated whether the administration of granulocyte colony-stimulating factor (G-CSF) when monocytopenia appears lessens neutropenia during chemotherapy for lung cancer. Between June 1997 and August 1998, 60 patients who received chemotherapy at 3- or 4-week intervals for unresectable lung cancer were randomized to receive G-CSF (2 microg/kg or 50 microg/m2) when monocytopenia (<150/microl) appeared on days 6 to 8 after chemotherapy (group A) or when neutropenia (<1,000/microl) or leukopenia (<2,000/ microl) appeared after chemotherapy (group B). The administration of G-CSF was stopped when the leukocyte or neutrophil counts reached > 10,000/microl or 5,000/microl, respectively. The blood cells counts were examined three times a week and the degree, duration, and frequency of chemotherapy-induced neutropenia of the two groups were compared. One patient in group A was excluded because whole brain irradiation during chemotherapy was required. Twenty-nine and 30 patients in groups A and B, respectively, received platinum-based chemotherapy and their chemotherapy-induced hematologic toxicities were analyzed. The mean neutrophil count nadir of group A (1,558 +/- 1,771/microl) was significantly higher than that of group B (810 +/- 639/microl, p = 0.032). The duration of grade III neutropenia in group A (1.4 +/- 1.7 days) was significantly shorter than that in group B (2.9 +/- 1.9 days, p = 0.004), and the frequency of grade III neutropenia in group A (48%) was significantly lower than that in group B (83%, p = 0.002). Infectious episodes occurred in five and eight patients in groups A and B, respectively. The durations of G-CSF therapy required by group A and B patients (4.8 +/- 3.1 vs. 4.7 +/- 2.7 days) were not significantly different. Prophylactic administration of G-CSF did not exacerbate anemia or thrombocytopenia induced by chemotherapy. We conclude that the prophylactic administration of G-CSF when monocytopenia appears can lessen neutropenia caused by chemotherapy for lung cancer without increasing the total G-CSF dose.

[Acute respiratory failure caused by tuberculosis requiring mechanical ventilation]

The patients with active tuberculosis in whom respiratory failure requiring mechanical ventilation developed were studied retrospectively. Nine patients (M 8, F 1) were identified at the National Tokyo Hospital during 5 years from January, 1993 to December, 1997. Seven of 9 patients were single men, and the duration of symptoms before admission was over 1 month in all patients, while the time from first visit to diagnosis was less than 7 days. All patients were identified as malnourished, and 7 patients suffered from another underlying diseases. The patients were classified into two groups. Six of 9 patients had pulmonary tuberculosis and the other three had miliary disease. The proportion of cases requiring mechanical ventilation was 0.3% and 8.6%, respectively, in pulmonary tuberculosis and miliary tuberculosis. At the start of mechanical ventilation, PaO2/FIO2 was lower than 200 in all 9 patients, and 6 patients were probably ARDS. Steroids (methylprednisolone 250-1000 mg/day) were used in all 9 patients. Despite the use of mechanical ventilation and antituberculous therapy, 8 out of 9 patients died. Only one patient with miliary tuberculosis survived. The establishment of the therapy for acute respiratory failure is needed so as to improve prognosis of such cases. At the same time, the delay in consulting a doctor led to acute respiratory failure in most cases, so it is also important to encourage tuberculosis patients to visit a doctor as soon as possible, after the appearance of symptoms.

Increased expression levels of cyclin-dependent kinase inhibitor p27 correlate with good responses to platinum-based chemotherapy in non-small cell lung cancer

In order to determine whether expression of the cyclin-dependent kinase inhibitor p27 in non-small cell lung cancer (NSCLC) correlates with chemotherapeutic response, resected tumors from 22 patients with recurrent lung cancer who had undergone complete resection and received chemotherapy after the initial tumor recurrence were subjected to p27 immunostaining. Histological examination of the resected tumors revealed 14 adenocarcinomas, 7 squamous cell carcinomas and one adenosquamous cell carcinoma. Fifty percent or less and over 50% of the cells in the resected tumors of 11 patients each (groups 1 and 2, respectively) were p27-immunopositive. All but one patient received platinum-based chemotherapy after recurrence. Only one in group 1 achieved a partial response (PR) in chemotherapy whereas 2 and 4 in group 2 achieved complete and PRs, respectively. The chemotherapy response rate of group 2 (54%) was significantly higher than that of group 1 (9%, p=0.022). The times to recurrence after tumor resection of the 2 groups did not differ significantly (log-rank p=0.23, Wilcoxon p=0. 32), but survival after chemotherapy of group 2 was significantly better than that of group 1 (log-rank p=0.045, Wilcoxon p=0.028). It is suggested that high p27 expression levels in tumors may predict the good responses to platinum-based chemotherapy for NSCLC.

N-[4-(3-ethoxy-2-hydropropoxy)phenyl] acrylamide selectively induces apoptosis of cerebellar granule cells in vivo and in vitro in rats

Oral administration of N-[4-(3-ethoxy-2-hydropropoxy)phenyl] acrylamide (EHA) induced selective granule cell destruction in the granular layer of the cerebellar cortex together with neurological signs, such as delayed righting reflex, gait or truncal ataxia, and convulsion. Neuropathologically, it caused multifocal granule cell destruction with nuclear pyknosis and spongiosis of the neuropile in the granular layer. Other neurons, including Purkinje cells, were spared. Ultrastructurally, damaged granule cells showed aggregation of nuclear chromatin and cytoplasmic edema, but cytoplasmic organelles were preserved. The brain uptake index of 14C-labeled EHA was similar to that of H2O. When EHA was added to rat cerebellar tissue cultures, only the granule cells showed nuclear pyknosis, aggregation of nuclear chromatin, and karyorrhexis with cytoplasmic swelling. These granule cells were positive for DNA fragmentation by the TUNEL method. These results suggest that EHA permeates the blood vessel wall and directly affects the cerebellar granule cells, resulting in selective granule cell apoptosis.

Beat-by-beat double-normalized pulse volume derived photoplethysmographically as a new quantitative index of finger vascular tone in humans

Near-infrared finger photoplethysmograms were recorded and double-normalized pulse volumes (DNPV = DeltaV(b)/V(b); V(b) = total blood volume in the fingertip, DeltaV(b) = pulsatile component of V(b)) were calculated in ten subjects during, immersion of the contralateral hand in water at three different temperatures (44 degrees C, 22 degrees C, 11 degrees C). The DNPV from the left finger was compared beat-by-beat with cutaneous vascular resistance (CVR) derived by dividing mean blood pressure of the left third finger by cutaneous blood flow of the left fourth finger. The correlations overall at the three temperatures between log DNPV(LF) and log CVR(LF) (LF, low frequency component of DNPV and CVR) ranged from -0.89 to -0.96 among the subjects. After adjusting for a maximal extension of the vascular wall (DNPV(max)), the correlations became stronger. It was concluded that DNPV was a reliable and valid indicator of vascular tone in the finger.

Effect of clarithromycin on Pseudomonas aeruginosa biofilms

Using an experimental in vitro culture system, we investigated the effect of clarithromycin on biofilm formation by a leucine-requiring Pseudomonas aeruginosa mutant strain (HU1). Biofilm formation on celldesks in a chemically defined medium was assessed by viable cell count as well as by measurement of glycocalyx production and scanning electron-microscopic observation. Cells proliferated exponentially until day 3 and remained stationary afterwards. The amount of glycocalyx, simultaneously semiquantified, showed a linear increase from day 1 to day 12. Scanning electron microscopy revealed firm biofilms on day 5. Three different concentrations of Clarithromycin (CAM) (minimum inhibitory concentration MIC 64 microg/ml) were added continuously at the early and late phases of biofilm formation, and the antibiofilm effect of CAM was evaluated by the changes in cell count and glycocalyx production. CAM was effective on biofilms at 100 microg/ml but neither at 1 nor at 10 microg/ml. It is suggested that glycocalyx production started following bacterial multiplication and continued even after the cells had entered the stationary phase to form mature biofilms. No antibiofilm effect of CAM was observed at sub-MIC.

Spatial and temporal variation of secondary flow during oscillatory flow in model human central airways

Axial and secondary velocity profiles were measured in a model human central airway to clarify the oscillatory flow structure during high-frequency oscillation. We used a rigid model of human airways consisting of asymmetrical bifurcations up to third generation. Velocities in each branch of the bifurcations were measured by two-color laser-Doppler velocimeter. The secondary velocity magnitudes and the deflection of axial velocity were dependent not only on the branching angle and curvature ratio of each bifurcation, but also strongly depended on the shape of the path generated by the cascade of branches. Secondary flow velocities were higher in the left bronchus than in the right bronchus. This spatial variation of secondary flow was well correlated with differing gas transport rates between the left and right main bronchus.