Cytokines modulate cilomilast response in lung fibroblasts

Fibroblasts, as a major source of extracellular interstitial connective tissue matrix, play an important role in wound healing and the development of fibrosis. The phosphodiesterase (PDE) 4 inhibitor cilomilast inhibits fibroblast chemotaxis and fibroblast-mediated gel contraction. Using the Boyden blindwell chamber chemotaxis assay and the type I collagen gel contraction model, this study investigated whether specific cytokines modulate cilomilast's inhibitory effect through regulation of endogenous PGE(2) production. Human recombinant IL-1beta stimulated PGE(2) production and shifted the cilomilast concentration-dependence curve to the left in both assay systems, indicating increased sensitivity to cilomilast. In contrast, human recombinant IL-4 inhibited PGE(2) production and shifted the cilomilast concentration-dependence curve to the right in both systems. In summary, the inhibitory effect of cilomilast on fibroblast migration and collagen gel contraction is modulated by IL-1beta and IL-4 through regulation of PGE(2) production.     

Dominant expression of interleukin-10 and transforming growth factor-beta genes in activated T-cells of chronic active Epstein-Barr virus infection

Chronic active Epstein-Barr virus (EBV) infection is a chronic mononucleosis syndrome associated with clonal proliferation of EBV-carrying T-/natural killer (NK)-cells. High levels of circulating EBV and activated T-cells are sustained during the prolonged disease course, whereas it is not clear how ectopic EBV infection in T-/NK-cells has been established and maintained. To assess the biological role of activated T-cells in chronic active EBV infection (CAEBV), EBV DNA and cellular gene expressions in peripheral T-cells were quantified in CAEBV and infectious mononucleosis (IM) patients. In CAEBV, HLA-DR(+) T-cells had higher viral load and larger amounts of IFN gamma, IL-10, transforming growth factor-beta (TGF beta), and cytotoxic T lymphocyte antigen-4 (CTLA4) mRNA than HLA-DR(-)T-cells. HLA-DR(+) T cells of IM patients transcribed more IFN gamma and IL-10 than their HLA-DR(-)T cells. Expression levels of IFN gamma and forkhead box p3 (Foxp3) in CAEBV HLA-DR(+) T-cells were higher than in IM HLA-DR(+) T-cells. The effective variables to discriminate the positivity of HLA-DR were IL-10, IFN gamma, CTLA4, TGF beta, and IL-2 in the order of statistical weight. EBV load in CAEBV T-cells correlated with the expression levels of only IL-10 and TGF beta. These results suggest that CAEBV T-cells are activated to transcribe IFN gamma, IL-10, and TGF beta excessively, and the latter two genes are expressed preferentially in the EBV-infected subsets. The dominant expression of regulatory cytokines in T-cells may imply a viral evasion mechanism in the disease.     

Conduction properties of identified neural pathways in the central nervous system of mice in vivo

Various lines of transgenic or knockout mice are now available that have abnormalities in neuron, glial cells or neuron-glial interaction. However, the techniques for quantitative analysis of their pathophysiological functions are still limited. We established an experimental model system to measure the properties of nerve conduction of identified neural pathways in the CNS using anesthetized and immobilized mice. Dorsal column (DC), vestibulospinal/reticulospinal tracts (VRST) and pyramidal tract (PT) were stimulated by inserting stimulating electrodes into the dorsal column nuclei, medial longitudinal fasciculus, and the medullary pyramid, respectively. Volleys were recorded at various segments in the cervical spinal cord with surface electrodes, and their conduction velocities (CVs) and relative refractory periods (RRPs) were measured. The CVs of the DC, VRST and PT were 26.25 +/- 4.96 m/s (n = 7), 51.55 +/- 4.65 m/s (n = 7), 8.89 +/- 1.81 m/s (n = 7), respectively. Data from paired stimulation indicated that the median values of RRPs of the DC, VRST and PT were 10, 2 and 4 ms, respectively, which suggested marked difference among individual tracts. This is the first attempt to measure the conduction properties of the central tracts in mice in vivo. This experimental procedure will give us a physiological measure of CNS functions in normal and genetically manipulated mice and contribute to clarifying the molecular mechanisms and pathophysiology of neurodegenerative diseases such as multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS).     

Optical mapping of neural responses and their gamma-aminobutyric acid-ergic inhibitory effects in the auditory brainstem of early postnatal mice

gamma-Aminobutyric acid (GABA)ergic neurons play important tropic and modulatory roles in the auditory pathway, especially in the early stage between postnatal Days 0 and 5. The effects of GABA and GABAa receptor antagonist were observed in this experimental study. Numerous histological and electrophysiological studies have been performed on the contribution of GABA to the auditory pathway; however, the spatio-temporal patterns of excitatory propagation and the relationships between GABA receptor and excitatory propagation have yet to be reported. Using an optical recording technique and a voltage-sensitive dye, the spatio-temporal patterns of excitatory propagation were observed in the auditory brainstem slices of early postnatal mice. A bath containing 50 microM GABA was applied, which largely inhibited the excitatory activities along the vestibulocochlear pathway. Bicuculline methiodide (BMI), a competitive antagonist against GABAa receptor, partially reversed the effects of GABA on the optical signals. Bath application of BMI alone helped to facilitate the depolarization course and its effect was apparent as an enlargement of the depolarized region from the cochlear nucleus and vestibular nucleus to some adjacent brainstem nuclei, as well as enhancing the amplitude of changes in the optical signals. The experimental results seem to suggest that GABAa receptors are widely distributed in an early postnatal auditory brainstem. GABA exhibited a greater modulating effect in the adjacent brainstem nuclei, which are involved in complex information processes, than that observed in the modulating primary auditory pathway. In the present experiment, significant GABAergic contributions to the optical recordings in the auditory brainstem were observed.     

Potential oscillation elicited by i.v. olfaction and its applicability as an objective clinical olfaction test

OBJECTIVE: Alinamin has long been applied in Japan for testing i.v. olfaction and to diagnose olfactory disorders. The test is subjective, each subject being asked about the presence or absence of olfaction. The credibility of the answers is highly questionable in some cases; as a result, the reliability of the test is poor. Recent studies demonstrated an induced electric potential in the scalp during i.v. olfactory testing. Some patients complain of the pain of the injection during i.v. olfactory testing; therefore, the effect of this pain must be considered with respect to measurement of the i.v. olfaction-elicited potential (IVOP). MATERIAL AND METHODS: This investigation involved 179 subjects with various olfaction levels. Each subject received an Alinamin injection; the elicited potential amplitude was compared before and after the injection and the increasing ratio (IR) was computed. Gender, age, level of olfactory disorder, the presence or absence of olfaction and the presence or absence of the pain of injection were considered as factors affecting IR. RESULTS: IR showed significant increases in groups characterized by the presence of olfaction as well as in groups reporting pain of injection. The test subjects were further divided into four groups based on their olfaction and pain of injection patterns as follows: Group A, no smell and no pain; Group B, smell and no pain; Group C, no smell and pain; and Group D, smell and pain. Subjects exhibiting no recognizable olfaction or pain of injection (Group A) revealed no increase in IVOP following injection. Subjects with either recognizable olfaction or pain of injection (Groups B and C) exhibited a slight increase in IVOP following injection. Subjects with both noticeable olfaction and pain of injection (Group D) demonstrated a significant increase in IVOP following the injection with a very high value of IR (>2). Furthermore, there were significant differences between the four groups in terms of IR level, with the exception of Groups B and C. CONCLUSIONS: Olfaction is largely involved with the generation of IVOP. However, pain resulting from injection of Alinamin is considered to be a significant factor. IVOP showed significant effectiveness for diagnosing olfactory disorders in cases who did not experience pain of injection.     

Near-infrared spectroscopy of the adult human olfactory cortex

OBJECTIVE: Near-infrared spectroscopy (NIRS) is a non-invasive method for investigating activation of the human cortex. The applicability of NIRS to the olfactory cortex was investigated. MATERIAL AND METHODS: The relative oxy- and deoxy-hemoglobin levels of the orbito-frontal cortex during olfactory stimulation in healthy subjects were measured using NIRS. RESULTS: When perfumed strips containing the odorants beta-phenyl ethyl alcohol, iso-valeric acid and gamma-undecalactone were presented, the oxy-hemoglobin level increased but the deoxy-hemoglobin level did not change. The increase in the oxy-hemoglobin level was observed bilaterally. A placebo perfumed strip did not elicit a change in the hemoglobin level. It was also observed that the odorant intensity affected the oxy-hemoglobin level. Although the orbito-frontal cortices seemed to be activated bilaterally during olfaction, the right cortex was activated to a greater extent than the left. CONCLUSION: NIRS appears to be an adequate method for investigating the human olfactory cortex.     

Clinical investigation of squamous cell carcinoma of the posterior oropharyngeal wall

Clinical features of 33 patients with squamous cell carcinoma of the posterior oropharyngeal wall treated at the Department of Otolaryngology, Head and Neck Surgery, Kurume University Hospital from 1973 to 2003 were analysed. Of these, 23 (21 men and 2 women, mean age: 66 years) underwent radical treatment, and 10 (8 men and 2 women, mean age: 78 years) did not. In those treated radically, 2 were stage I, 5 stage II, 6 stage III, and 10 stage IV. The primary disease was surgically treated in 16, and reconstruction added in 5, using the free jejunum in 4 and a forearm flap. Radical radiotherapy was done in 7. Five-year local control in the 23 was 35.3%. Disease-specific 5-year survival was 32.0%. Seven died of primary oropharyngeal cancer. After treatment, 78.3% were able to eat orally. In conclusion, squamous cell carcinoma of the posterior oropharyngeal wall is relatively rare and has a poorer prognosis than other types of oropharyngeal cancer.     

Role of Dok-1 and Dok-2 in myeloid homeostasis and suppression of leukemia

Dok-1 and Dok-2 are closely related rasGAP-associated docking proteins expressed preferentially in hematopoietic cells. Although they are phosphorylated upon activation of many protein tyrosine kinases (PTKs), including those coupled with cytokine receptors and oncogenic PTKs like Bcr-Abl, their physiological roles are largely unidentified. Here, we generated mice lacking Dok-1 and/or Dok-2, which included the double-deficient mice succumbed to myeloproliferative disease resembling human chronic myelogenous leukemia (CML) and chronic myelomonocytic leukemia. The double-deficient mice displayed medullary and extramedullary hyperplasia of granulocyte/macrophage progenitors with leukemic potential, and their myeloid cells showed hyperproliferation and hypo-apoptosis upon treatment and deprivation of cytokines, respectively. Consistently, the mutant myeloid cells showed enhanced Erk and Akt activation upon cytokine stimulation. Moreover, loss of Dok-1 and/or Dok-2 induced blastic transformation of chronic phase CML-like disease in mice carrying the bcr-abl gene, a cause of CML. These findings demonstrate that Dok-1 and Dok-2 are key negative regulators of cytokine responses and are essential for myeloid homeostasis and suppression of leukemia.