Serum sex hormone levels in adult patients with atopic dermatitis

Serum levels of sex hormones were measured in adult patients with atopic dermatitis (AD) and compared with those in sex- and age-matched healthy controls. In 40 male patients with AD, serum levels of testosterone (T) (447 +/- 96 vs 593 +/- 149 ng/dl, P < 0.001), free testosterone (FT) (14.6 +/- 3.2 vs 20.0 +/- 5.1 pg/ml, P < 0.001) and estradiol (E2) (27.2 +/- 7.2 vs 33.2 +/- 7.9 pg/ml, P < 0.05) were significantly lower and serum levels of luteinizing hormone (LH) (4.57 +/- 1.6 vs 3.11 +/- 1.2 mIU/ml, P < 0.001) were significantly higher than those in healthy controls. There were no significant differences in serum levels of dihydrotestosterone (DHT), dehydroepiandrosterone sulfate (DHEA-S), dehydroepiandrosterone (DHEA), or follicle stimulating hormone (FSH) between the two groups. In 25 female patients with atopic dermatitis, T, FT, DHT and DHEA-S levels did not differ from controls. In conclusion, serum T levels were lower in male patients with AD. However, similar changes were not seen in female patients.

Mild insulin resistance during oral glucose tolerance test (OGTT) in women with acne

The purpose of this study was to evaluate serum levels of basal insulin and glucose-stimulated insulin, and to evaluate their correlations with androgen levels in women with acne. Serum levels of total testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), dehydroepiandrosterone sulfate (DHEA-S), sex hormone binding globulin (SHBG), insulin-like growth factor-1 (IFG-1), and immunoreactive insulin (IRI) were measured and compared in thirty women with moderate or severe acne and thirteen healthy controls. Serum FT, DHT and DHEA-S levels in the acne group were significantly higher than those in the control group. In the acne group, there were no significant correlations between insulin or IGF-1 levels and T, FT, DHT and SHBG, despite the positive correlation between insulin and IGF-1. In order to determine the effects of insulin secretion as a dynamic response to an oral glucose tolerance test (OGTT) on serum androgen levels in acne patients, we examined the responses of serum insulin and androgen levels to a 75 g, 2 hour OGTT in the acne group and in the control group. Basal insulin levels were not significantly higher than those in the control group, but the summed insulin levels during the OGTT in the acne group were significantly higher than those in the control group. Serum T and FT levels in the acne group decreased during the OGTT, but these changes were not so significant when compared to normal controls. In conclusion, we tried to demonstrate mild insulin resistance during the OGTT in acne patients. However, postmeal transient hyperinsulinemia does not seem to play an important role in determining hyperandrogenemia in acne patients.

Role of tachykinins in airway narrowing induced by cigarette smoke in guinea pigs

To investigate the mechanism of the airway narrowing induced by cigarette smoke, anaesthetized guinea pigs were exposed to 200 puffs of smoke for 10 min. Airway narrowing was assessed by monitoring the total pulmonary resistance (R(L)). Plasma extravasation was determined by measuring the amount of Evans blue dye extravasated into the trachea and main bronchi. Exposure to cigarette smoke caused a marked airway narrowing and plasma extravasation. Pretreatment with the dual NK(1) and NK(2) receptor antagonist, FK224, abolished such airway narrowing and significantly inhibited the extravasation. While the NK(1) receptor antagonist, FK888, inhibited the extravasation, it had no effect on airway narrowing. Atropine partially inhibited airway narrowing without affecting extravasation. Results suggest that the airway narrowing induced by cigarette smoke is caused by tachykinins, and that a cholinergic pathway is involved. Thickening of the airway walls induced by NK(1) receptor-mediated extravasation may not be involved in such airway narrowing.

[A case of Nothnagel syndrome]

A 72-year-old woman developed a sudden onset of bilateral ptosis, diplopia and gait disturbance. Neurological examination revealed bilateral oculomotor palsies, truncal ataxia, and transient slight weakness in the right upper extremity. She was diagnosed to have Nothnagel syndrome. T2-weighted MRI disclosed a high signal intensity lesion at the left paracentral portion of the upper midbrain in addition to the bilateral medial thalamic lesions, while brain CT showed only the thalamic lesions. Brain MRI was useful for detecting the small midbrain lesion.

A case of varicella-zoster myelopathy

INTRODUCTION

Early diagnosis of neurological complications of varicella-zoster virus (VZV) is important because of its treatability. We performed polymerase chain reaction (PCR) to detect VZV-DNA from the cerebrospinal fluid (CSF) of a patient with myelopathy.

PATIENT & METHODS

A 69-year-old man developed sensory disturbances in the lower extremities and bladder-bowel disturbances, followed by cutaneous zoster on his left arm. Polymerase chain reaction was applied to identify the viral DNA in CSF.

RESULTS

The increased antibody index of VZV and herpes simplex virus (HSV) in the CSF suggested intrathecal synthesis of IgG antibodies to these viruses. VZV-DNA was detected in the CSF by nested PCR, but neither HSV-1 nor HSV-2 DNA was detected in CSF. He was successfully treated with acyclovir and prednisolone.

CONCLUSION

PCR may be a useful tool for the diagnosis of VZV myelopathy.

[Pulmonary arterio-venous fistula treated by embolization with steel coils]

A 63-year-old man was referred to our hospital for evaluation and treatment of severe dyspnea on exertion which had persisted for a few years. He presented with cyanosis and markedly clubbed fingers, and laboratory data disclosed hypoxemia, polycythemia, and liver dysfunction. A chest X-ray film showed increased vascular markings in both lower lung fields. Arterial blood gas analysis showed severe hypoxemia, with a PaO2 of 46 Torr and a PaCO2 of 31 Torr while the patient was breathing room air. The PaO2 increased only slightly with inhalation of 100% oxygen, which suggested the presence of a large R-L shunt. The hepatopulmonary syndrome was diagnosed. Angiography of the pulmonary artery revealed a large pulmonary arterio-venous fistula with markedly dilated arteries in both lower lobes. Transarterial embolization was done three times with a total of 62 metal coils. There were no complications. Embolization reduced the shunt from 56% to 31%, increased the PaO2, and relieved the dyspnea. Pulmonary artery embolization can be useful in treating pulmonary arterio-venous fistulas associated with the hepatopulmonary syndrome.

Mechanisms of mechanical stress-induced Ca(2+)-mobilization sensitized by lysophosphatidic acid in cultured smooth muscle cells

We have previously reported that lysophosphatidic acid (LPA) sensitizes mechanical stress-induced cytosolic free Ca2+ concentration ([Ca2+]i) response related to Ca2+ entry through Gd(3+)-sensitive ion channels (Biochem. Biophys. Res. Commun. 208 19-25 1995). Here we examined the contribution of Ca2 release from intracellular stores to the mechanical stress-induced [Ca2+]i response sensitized by LPA in cultured longitudinal muscle cells from guinea pig ileum. Although the percentage of responsive cells to the mechanical stress in the presence of 30 nM LPA declined by decreasing extracellular Ca2+ concentration to less than 20 microM, the amplitude of the mechanical stress-induced [Ca2+]i transient did not depend on extracellular Ca2+ concentrations (10 microM-1.8 mM). The [Ca2+]i transient was completely abolished by treatment with thapsigargin. In addition, the amplitude of the [Ca2+]i transient gradually decreased after ryanodine and caffeine treatment. These results indicate that the mechanical stress-induced [Ca2+]i transient in the presence of LPA is mainly due to Ca2+ release from ryanodine-sensitive intracellular stores and may be triggered by Ca2+ influx through Gd(3+)-sensitive ion channels.

An infrared video camera system to observe nocturnal scratching in atopic dermatitis patients

We used an infrared video camera and video tape recorder system to record and analyze nocturnal scratching in seven patients with atopic dermatitis (AD) and three non-itchy healthy controls. The patterns and the locations of scratching were successfully observed. Scratching bouts lasting more than 5 sec were counted, and the summation of the duration of all the scratching bouts (total scratching time, TST) was used as an index of nocturnal scratching. TST in patients with AD turned out to be some hundreds to ten thousands of seconds; the TST in controls was between zero and a hundred seconds. The infrared video camera system measured nocturnal scratching simply and reliably without disturbing the patients' sleep.

BAY u3405, a thromboxane A2 antagonist, reduces bronchial hyperresponsiveness in asthmatics

OBJECTIVE

Thromboxane A2 (TXA2) is reported to induce bronchial hyperresponsiveness along with the well-documented bronchoconstrictor action on smooth muscles. We examined the effect of the TXA2 antagonist, BAY u3405, on bronchial hyperresponsiveness to methacholine (MCh) in asthmatics.

PATIENTS

Twelve adult asthmatics were studied in a randomized, double-blind, placebo-controlled, crossover fashion.

DESIGN

Following a 2-week run-in period, the subjects were administered 75 mg of BAY u3405 or placebo orally, twice a day for 2 weeks each in a crossover design, interposing a 2-week washout period. Bronchial hyperresponsiveness was measured by the astograph method. Briefly, the respiratory resistance (Rrs) was measured by the forced oscillation method during continuous inhalation of MCh in stepwise incremental concentrations, until Rrs reached twice the baseline value. Bronchial hyperresponsiveness was evaluated as the minimum cumulative dose (Dmin) of MCh that induced an increase in Rrs. Dmin was calculated so that 1 U of Dmin equals to 1 min of inhalation of aerosol solution at 1.0 mg/mL during quiet breathing.

RESULTS

Three subjects were withdrawn from the evaluation because they had asthmatic attacks or wheezing during the study. The Dmin value of 0.533 U (GSEM 1.675) after the BAY u3405 treatment was significantly greater than that of 0.135 U (GSEM 1.969) after the placebo treatment (p = 0.0139). There were no safety concerns in either treatment group.

CONCLUSION

We conclude that BAY u3405 may be a useful drug for attenuating bronchial hyperresponsiveness in bronchial asthma.

Overexpression of cofilin stimulates bundling of actin filaments, membrane ruffling, and cell movement in Dictyostelium

Cofilin is a low molecular weight actin-modulating protein whose structure and function are conserved among eucaryotes. Cofilin exhibits in vitro both a monomeric actin-sequestering activity and a filamentous actin-severing activity. To investigate in vivo functions of cofilin, cofilin was overexpressed in Dictyostelium discoideum cells. An increase in the content of D. discoideum cofilin (d-cofilin) by sevenfold induced a co-overproduction of actin by threefold. In cells over-expressing d-cofilin, the amount of filamentous actin but not that of monomeric actin was increased. Overexpressed d-cofilin co-sedimented with actin filaments, suggesting that the sequestering activity of d-cofilin is weak in vivo. The overexpression of d-cofilin increased actin bundles just beneath ruffling membranes where d-cofilin was co-localized. The overexpression of d-cofilin also stimulated cell movement as well as membrane ruffling. We have demonstrated in vitro that d-cofilin transformed latticework of actin filaments cross-linked by alpha-actinin into bundles probably by severing the filaments. D. discoideum cofilin may sever actin filaments in vivo and induce bundling of the filaments in the presence of cross-linking proteins so as to generate contractile systems involved in membrane ruffling and cell movement.

Thromboxane A2 mimetic (U-46619) induces hyperresponsiveness of smooth muscle in the canine bronchiole, but not in the trachea

It has been reported that cholinergic agonists induce bronchoconstriction by directly stimulating M3 muscarinic receptors on the surfaces of smooth muscle cells. Although thromboxane A2 (TXA2) has been demonstrated to induce airway hyperresponsiveness to cholinergic agonists in vivo, it does not affect the contractile response of smooth muscle to cholinergic agonists in vitro. To investigate the causes for the discrepancy between the in vivo and in vitro data, we compared the effects exerted by a TXA2 mimetic, U-46619, on the smooth muscle of canine trachea and bronchiole. We measured the contractile response to exogenously applied acetylcholine (ACh) before and after the application of a subthreshold dose of U-46619. The subthreshold dose was determined as that dose which did not induce smooth muscle contraction, this being 10(-9) M in the present study. The contractile responses of tracheal strips to ACh were not affected by the subthreshold dose of U-46619. By contrast, the responses of bronchiolar rings were significantly enhanced by this subthreshold dose. The excitatory effect of U-46619 on the ACh-induced contraction was completely prevented by treatment with a TXA2 antagonist, BAY u3405. These results indicate that TXA2 directly increases the responsiveness of smooth muscle in the bronchiole, and suggest that increases in the responsiveness of small airways may play an important role in the development of the airway hyperresponsiveness induced by TXA2.

Activation of the proteasome during Xenopus egg activation implies a link between proteasome activation and intracellular calcium release

Ubiquitin-dependent proteolysis is required for cell cycle progression. Here, we demonstrate that the proteasome is activated during in vivo Xenopus egg activation, induced by treatment with the calcium ionophore A23187. It was found that activation is due to the calcium-induced assembly of the 26 S proteasome from the 20 S proteasome. We propose that proteasome activation is regulated by cell cycle calcium transients, which are controlled upstream by an endogenous cell cycle oscillator that is independent of the cyclin-dependent kinase cycle.

Cultured epithelial cells release cyclooxygenase-dependent and cyclooxygenase-independent factors that inhibit cholinergic contraction of canine airway smooth muscles

We observed the effects of supernatants from cultured epithelial cells on the contraction of tracheal smooth muscle evoked by acetylcholine (ACh) or by electrical field stimulation (EFS). Cultured canine tracheal epithelial cells were incubated in Krebs solution with or without indomethacin (10(-5)M) for 30 and 120 min. The amplitude of the tracheal smooth muscle contractions evoked by EFS or exogenously applied ACh were measured before and after the application of each supernatant in the combined presence of both indomethacin (10(-5)M) and propranolol (10(-6)M). The control supernatant incubated without indomethacin markedly suppressed the amplitude of the contraction evoked by EFS, but not by ACh. The supernatant incubated with indomethacin for 30 min did not show any effects on the contractile responses evoked by EFS or ACh. However, the supernatants from the cultured epithelial cells incubated for a longer period (120 min) in the presence of indomethacin significantly suppressed the contraction evoked by EFS, but not by ACh. The prostaglandin E2 (PGE2) concentration was markedly higher in the supernatants incubated without indomethacin (1.39 +/- 0.51 ng/ml, 30 min incubation) than in those with indomethacin (0.02 +/- 0.01 ng/ml, 30 min incubation, and 0.06 +/- 0.01 ng/ml, 120 min incubation). To determine whether PGE2 is responsible for the inhibitory effect of the supernatants, we evaluated the effects of PGE2 on the resting tone, and EFS- or ACh-evoked contraction. 10(-12) to 10(-6) M of PGE2 showed no significant effect on the resting tone. 10(-9) M of PGE2, corresponding to the concentration of the supernatants incubated without indomethacin, and 10(-11) M of PGE2, to that of the supernatants incubated with indomethacin, showed a similar extent of inhibitory effects to the corresponding supernatants on the EFS-evoked contraction, and no effect on the ACh-evoked contraction. These results suggest that cultured airway epithelial cells release at least two factors spontaneously even without stimulation. One of these factors may be prostanoid (PGE2), which acts prejunctionally to inhibit the contractile response. The other factor is distinct from prostanoid and inhibits smooth muscle contraction, presumably by suppressing ACh release from vagus nerve termini.

[Inhibitory non-adrenergic, non-cholinergic nerves and nitric oxide]

We studied the role of nitric oxide and inhibitory non-adrenergic, non-cholinergic (i-NANC) nerves in the regulation of airway responsiveness in anesthetized and mechanically ventilated cats. Vagal stimulation caused marked bronchodilation in the cats with sustained bronchoconstriction in the presence of atropine and propranolol. The bronchodilation evoked by vagal stimulation was completely abolished by hexamethonium (2 mg/kg). L-NG-nitroarginine methyl ester (L-NAME; 8 mg/kg + 2 mg/kg/min) significantly suppressed the relaxation evoked by vagal stimulation; the effect was particularly noticeable soon after the stimulation. Hexamethonium significantly increased airway responsiveness to serotonin: the PC200 decreased from 0.346 mg/ml (GSEM 1.23) without hexamethonium to 0.44 mg/ml (GSEM 1.63) with hexamethonium (p < 0.05). L-NAME shifted the dose-response curve to serotonin significantly to the left: the PC200 decreased from 0.261 mg/ml (GSEM 1.,40) without L-NAME to 0.056mg/dl (GSEM 1.38) with L-NAME (p < 0.05). Inhalation of citric acid (20%) caused marked bronchodilation during serotonin-induced bronchoconstriction. This bronchodilation occurred in the presence of atropine and propranolol and was inhibited by hexamethonium, therefore it was probably caused by a reflex mediated by i-NANC nerves. Furthermore, the bronchodilation induced by i-NANC nerves was significantly suppressed by L-NAME. These results suggest that nitric oxide is an important i-NANC transmitter that can modulate airway responsiveness.

Exertional rhabdomyolysis as a result of strenuous military training

We reviewed biochemical data from 19 soldiers who marched intermittently over 4 weeks, carrying about 45 kg of kit, with a limited intake of food and water. The mean serum creatine kinase activity was higher after the march (p < 0.01), although the subjects did not develop symptomatic rhabdomyolysis. The mean serum potassium level (p < 0.005) and the mean serum sodium level (p < 0.05) were lower after the march. The level of serum osmolality showed no significant changes. Subclinical rhabdomyolysis was not rare among the soldiers. We also report a case of the soldier with exertional clinical rhabdomyolysis.

Effect of BAY u3405, a thromboxane A2 receptor antagonist, on neuro-effector transmission in canine tracheal tissue

Thromboxane A2 (TXA2) is reported to potentiate vagal nerve neuro-effector transmission in airway smooth muscle tissue. We investigated the effects of BAY u3405 (3(R)-[[4-fluorophenyl)sulfonyl]amino]-1,2,3,4,-tetrahydro-9H-carbazole - 9-propanoic acid), a potent and selective TXA2 receptor antagonist, on the increase in vagal nerve neuro-effector transmission induced by a TXA2 mimetic, U-46619, in the canine trachea. We measured the contractions of canine tracheal smooth muscle evoked by electrical field stimulation (EFS) and by acetylcholine (ACh) in the presence and absence of a subthreshold dose of U-46619 (the highest dose that did not induce any smooth muscle contraction). We then examined whether BAY u3405 inhibited the effect of U-46619 on tracheal smooth muscle. The following results were obtained: (i) subthreshold doses of U-46619 (10(-10) M and 10(-9) M) significantly increased the amplitude of the contractions evoked by EFS; (ii) by contrast, U-46619 had no effect on the contractile response of smooth muscle to exogenously applied ACh; (iii) the contraction evoked by EFS was completely abolished by the application of atropine (10(-6) M) or tetrodotoxin (10(-7) M), indicating that EFS caused the smooth muscle contraction through the release of ACh from vagal nerve terminals; and (iv) pretreatment with BAY u3405 (10(-6) M) abolished the excitatory action of U-46619 on the amplitude of twitch contraction evoked by EFS in the trachea. These results indicate that U-46619, at low concentrations, has a prejunctional action stimulating neuro-effector transmission, presumably increasing ACh release from vagal nerve terminals through TXA2 receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of rhabdomyolysis complicated with myocardial injury]

A 22-year-old man developed transient unconsciousness during running. He developed fever, nausea, vomiting, diarrhea and general fatigue. Next day, he was admitted to National Hospital Nayoro because of high serum CK level of 13,610U/l. Biochemical analyses revealed elevated serum myoglobin, increased CK-MM isozyme, aldolase and lactate dehydrogenase, increased serum osmolality, increased uric acid, and decreased serum potassium levels. Therefore, he was diagnosed as having rhabdomyolysis. In addition, serum CK-MB isozyme, cardiac myosin light chain I and troponin T were increased, suggesting the damage of cardiac muscle. Electrocardiogram showed elevated ST segment and inverted T on V2-4, which were not observed previously. He had no preceding infectious disease, drug ingestion or an underlying metabolic disorder. The rhabdomyolysis may be precipitated by the superimposition of dehydration and loss of potassium due to diarrhea and vomiting. The myocardial injury, probably produced by transient myocardial ischemia, should be paid attention in case of rhabdomyolysis.

Protein kinase C is involved in translocation of diacyglycerol kinase induced by carbachol in guinea pig taenia coli

The regulatory mechanisms of diacylglycerol (DG) kinase activity were studied in guinea pig taenia coli. In an octylglycoside mixed micellar assay system, DG kinase activities were distributed in both membrane and cytosolic fractions. Treatment of the tissue with carbachol (CCh) increased the activity in the membrane fraction and decreased the cytosolic fraction without affecting total DG kinase activity. The Km value of DG kinase in the membrane fraction was unchanged by treatment with CCh, although Vmax was increased. These findings suggest that DG kinase may be translocated from the cytosol to the membrane by CCh-stimulation. Increase in DG content by treatment of tissue with a cell-permeable species of DG, dioctanoyl-sn-glycerol, did not induce DG kinase translocation. Each treatment with protein kinase C (PKC) inhibitor and PKC-desensitization blocked CCh-induced DG kinase translocation; and phorbol ester induced the translocation only in intracellular calcium-accumulated tissues. Considering these results, CCh-induced DG kinase activation appears to involve DG kinase translocation from the cytosol to the membrane in association with both PKC and intracellular calcium concentration rather than cellular DG content.

Insertion-site anatomy of the human menisci: gross, arthroscopic, and topographical anatomy as a basis for meniscal transplantation

A cadaveric study was performed to determine the insertion-site anatomy of the human menisci, their topographical relationships to adjacent intra-articular structures, and which arthroscopic portal provides for optimal visualization of each insertion site. Fifteen fresh-frozen cadaver knees were studied (ages 48 to 63 years). Ten knees underwent arthroscopy using four standard arthroscopic portals. Visualization and placement of an arthroscopic guide over each meniscal horn insertion site was attempted through the four arthroscopic portals. Guide wires were drilled to mark horn insertions followed by a gross dissection to evaluate accuracy of the guide wire gross dissection to evaluate accuracy of the guide wire placement and to isolate meniscal horn insertion sites. Insertion sites were outlined and evaluated for size and topographical relationships to other intra-articular structures. Five additional knees were dissected free of all soft tissues except the tibial insertions of the meniscal roots and anterior cruciate ligament/posterior cruciate ligament. Each tibia was mounted in a jig and a digitizing system was used to record coordinates of points along the outline of each bony meniscal horn insertion site, the ACL tibial insertion, and the articular surface of each tibial plateau. The x, y, z coordinates for each point were calculated and loaded into a computer program allowing for surface area determination and computer-generated topographical maps to assess relative position of each specific insertion site. Placement of the arthroscope in the anterolateral portal allows optimal visualization and guide wire placement for both lateral meniscal horn insertion sites. Medial meniscal anterior and posterior horn insertion sites are best visualized with the arthroscope in the anteromedial and posteromedial portals respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Androgen status in adolescent women with acne vulgaris

Androgens are essential for the development of acne. The object of this study was to elucidate the androgen status of women with adolescent (Tanner's stage IV-V) acne alone and compare them to age-matched normal controls. We measured serum levels of total testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), and dehydroepiandrosterone sulfate (DHEA-S) in 15 women with adolescent acne and 13 age-matched healthy controls. No significant differences were found between the mean levels of T, FT or DHT levels in patients and controls. However, the mean levels of DHEA-S in the patient population (1886 +/- 829 ng/ml) were significantly (p < 0.05) higher than normal controls (1287 +/- 620 ng/ml). There was also no correlation between androgen levels and acne severity. Thus it is unlikely that serum androgens play a principal role in women with adolescent acne.

[A case of post-traumatic arteriovenous fistula of the subclavian artery]

A 67-year-old woman was admitted to our hospital for a complete medical evaluation of a pulmonary nodule on a chest X-ray film, which was found during an annual check-up. A loud bruit was audible over the left chest and the supraclavicular region. Computerized tomography (CT) scan and magnetic resonance imaging revealed an arteriovenous fistula from a branch of the left subclavian artery into the paravertebral veins. Angiography disclosed that the arteriovenous fistula was fed by the left costocervical artery. Transarterial embolization of the arteriovenous fistula was done with 5 mechanical detachable coils and 2 micro coils. Postembolization angiography showed a marked decrease in blood flow and near-elimination of the arteriovenous fistula. The shrinkage of the arteriovenous fistula was also observed on CT scan. This patient had been in a traffic accident, and had been clinically well before the accident. Post-traumatic arteriovenous fistula was strongly suspected, because a pulmonary nodule on chest X-ray film and a bruit were found after a traffic accident.

An important role of tachykinins in ozone-induced airway hyperresponsiveness

We investigated the role of tachykinins in ozone-induced airway hyperresponsiveness (AHR) in guinea pigs. Airway responsiveness was assessed by determining the provocative concentration (PC200) of a histamine aerosol. Ozone exposure (3.0 ppm for 2 h) caused significant AHR. For vehicle-pretreated animals, the geometric mean pre- and post-ozone PC200 values were 0.87 mg/ml (GSEM 1.33) and 0.11 mg/ml (GSEM 1.17), respectively. Tachykinin depletion by capsaicin (50 mg/kg) prevented this AHR, whereas it did not alter pre-ozone airway responsiveness. The PC200 was 0.36 mg/kg (GSEM 1.64) before ozone and 0.24 mg/kg (GSEM 1.72) after ozone for this group. Ozone also caused a significant increase in neutrophils in bronchoalveolar lavage fluid (BALF) compared with BALF from a normal control group (1.71 +/- 0.69 versus 0.07 +/- 0.02 x 10(5)/ml, respectively). Capsaicin pretreatment attenuated this neutrophil influx (0.23 +/- 0.16 x 10(5)/ml). Morphometric assessment revealed edema of the bronchiolar wall after ozone exposure, which was not observed in the capsaicin group. BAL and morphometry revealed that the degree of ozone-induced epithelial desquamation was similar in both groups. These results suggest that tachykinins may be responsible for ozone-induced AHR, possibly via neurogenic inflammation.

Identification, characterization, and intracellular distribution of cofilin in Dictyostelium discoideum

We identified and purified an actin monomer-binding protein of apparent molecular weight of 15,000 from Dictyostelium discoideum. The 15-kDa protein depolymerized actin filaments in a pH-dependent manner. The protein also had an activity to decrease apparent viscosity of actin solutions in a dose-dependent manner. This activity was inhibited by phosphatidyl inositides. Molecular cloning of genes encoding this protein revealed that the protein is 42% identical in its primary sequence to yeast cofilin. We concluded that the 15-kDa protein is cofilin of this organism. D. discoideum cells contain two cofilin genes (DCOF1 and DCOF2) whose nucleotide sequences were entirely identical in their exsons while the promoter and intron regions were different. Promoter assay experiments revealed that DCOF1 is expressed both in vegetative and differentiating cells and that DCOF2 is not expressed under any conditions examined. Gene disruption experiments suggested that DCOF1 might be essential for the proliferation of D. discoideum cells whereas the disruption of DCOF2 was proven not to alter any phenotypes. Indirect immunofluorescence microscopic observations showed that cofilin is distributed diffusely throughout cytoplasm in vegetative cells. In flattened cells under starvation stress, cofilin localized at dramatically reorganizing actin-cytoskeletons in ruffling membranes of the leading edge, but not at rigid actin meshwork in focal adhesion plaques. These results suggest that cofilin may be involved in dynamic reorganization of membranous actin cytoskeletons.

[A case of pulmonary eosinophilic granuloma and diabetes insipidus]

A 31-year-old man was admitted to our hospital because of a sudden onset of thirst, polyposia, and polyuria. Five years previously he had been admitted to our hospital because of a dry cough. On the first admission, the chest X-ray film had shown reticular shadows and bullous changes in both upper lung fields. Histological examination of a transbronchial lung biopsy specimen had revealed that the nodular lesion in the interstitium of the alveolar lesion consisted of an aggregate of many Langerhans cells with pale cytoplasm and partly convoluted nuclei. In addition, immunoperoxidase stain for S-100 protein had been strongly positive in numerous Langerhans cells in a bone biopsy specimen from a left mandibullar lesion, which is the same histological appearance as the lung lesion. A diagnosis of pulmonary eosinophilic granuloma had been made. The course after discharge was not progressive without treatment for 5 years, but the patient suddenly began to have thirst, polyposia, and polyuria. Dehydration, vasopressin tests, and the findings of MRI indicated diabetes insipidus due to a pathological change in the pituitary gland. Although diabetes insipidus is known to be a common complication of pulmonary eosinophilic granuloma, only 9 cases have been reported in Japan.