Multi-and Single-Walled Boron Nitride Nanotubes Produced From Carbon Nanotubes by a Substitution Reaction

Boron nitride (BN) multi-walled (MWNT) or single-walled (SWNT) nanotubes were synthesized from carbon MWNT and SWNT templates, respectively, under heating of C nanotubes together with boron trioxide in a flowing nitrogen atmosphere. B and N atom substitution for C atoms in the nanotubular shells during C oxidation by the B2O3 vapor in the N2 flow is thought to underlie the formation mechanism. Structural and chemical BN MWNT/SWNT analyses were performed by means of high-resolution electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS), respectively. In particular, BN MWNT shell structure and defects, and electron irradiation stability were studied. Finally, the prospects of using the substitution technique for the synthesis of other advanced nanostructures made of BN (nanorods, nanoplates and nanocones) are discussed.

Smoking-related changes in the background lung of specimens resected for lung cancer: a semiquantitative study with correlation to postoperative course

AIMS

To assess the pathological findings in lobectomy specimens, to correlate them with smoking history and postoperative course and to compare the findings with those in smoking-related interstitial lung disease.

METHODS AND RESULTS

Patients who had undergone lobectomy for lung cancer were reviewed. Subjects included 230 non-smokers and 587 smokers, of whom 572 had a known smoking index (SI). They were classified into mild, moderate and heavy smokers. Centrilobular emphysema (CLE), respiratory bronchiolitis, airspace enlargement with fibrosis (AEF), the presence of foci resembling usual interstitial pneumonia pattern (UIP/P) and the rate of postoperative respiratory failure were assessed. The incidence of AEF was 6.5% in mild smokers, and 17.7% in moderate smokers (P < 0.01) with lower lobe predominance. There were significant correlations (P < 0.01) between AEF and CLE and AEF and UIP/P. The rate of respiratory failure after lobectomy was 6%, and 10% in patients having UIP/P with or without AEF, but was not seen in patients with AEF alone (P < 0.01).

CONCLUSIONS

AEF is an important smoking-related change in the lung that appears to correlate with the smoking history, and its distinction from UIP/P may be important.

Use of the ultrasonically activated scalpel in acoustic neuroma surgery: preliminary report

Recently, the ultrasonic activated scalpel (the Harmonic Scalpel, HS) has been introduced in laparoscopic surgery. We have applied the HS in debulking the tumor in the posterior fossa and concluded that this is useful in acoustic neuroma surgery. Fifteen patients with a tumor extending more than 20 mm into the posterior fossa were included in this study. The extended middle cranial fossa approach type II was used in 13 patients and type III (hearing preservation surgery) was used in 2 patients. In one of two patients, hearing was preserved. Postroperative facial nerve function according to the House-Brackmann method was grade I in 12 patients, grade II in 2 patients, and grade III in 1 patient. Compating the technique of using HS to a pair of bipolar forceps and/or ultrasonic cavitational aspirator, the former can result in better preservation of the facial nerve function.

Alcohol consumption and the risk of cancer in Japanese men: the Miyagi cohort study

The objective of this study was to investigate the association between alcohol consumption and the risk of total cancer, and to estimate the proportion of total cancer attributable to drinking habit in Japanese men. From June through August 1990, a total of 21 201 Japanese men completed a self-administered questionnaire on various health habits, including alcohol consumption. During 153 389 person-years of follow-up through December 1997, we identified a total of 882 cases of cancer. We used Cox proportional hazards regression to estimate the relative risk of total cancer according to categories of alcohol consumption. The risk for total cancer was significantly higher in ex-drinkers than never-drinkers. There was a dose-response relationship between the amount of alcohol consumed and the risk of total cancer among current drinkers: multivariate RRs in reference to never-drinkers (95% confidence intervals (CI)) were 1.1 (0.8-1.3), 1.3 (1.0-1.7), and 1.3 (1.1-1.7) in current drinkers who consumed less than 22.8 g, 22.8-45.5 g, 45.6 g or more alcohol per day, respectively (P for trend <0.001). Estimated 17.9% (95% CI 3.1-30.5) of total cancer risk was attributable to drinking habit. In our findings, approximately 20% of the total cancer cases in Japanese men may be prevented by alcohol control.

Enhanced airway inflammation and decreased subepithelial fibrosis in interleukin 6-deficient mice following chronic exposure to aerosolized antigen

BACKGROUND

Airway inflammation and remodelling are characteristic features of chronic asthma.

OBJECTIVE

To elucidate the role of interleukin (IL)-6 in airway responses to chronic antigen exposure.

METHODS

We compared airway inflammation, subepithelial collagen deposition, cytokine mRNA expression, and airway responsiveness between IL-6-deficient and wild-type (WT) mice following sensitization and repeated exposure to ovalbumin (OVA) three times a week for 8 weeks.

RESULTS

The repeated exposure to OVA induced infiltration of eosinophils, neutrophils, and lymphocytes into the airway, and caused thickening of the basement membrane and subepithelial fibrosis. IL-6-deficient mice exhibited more pronounced infiltration of these cells, a thinner basement membrane, and decreased subepithelial fibrosis, compared with WT mice. The repeated OVA exposure increased expression of IL-4, IL-13, eotaxin, monocyte chemoattractant protein-1 (MCP-1), and transforming growth factor-beta1 mRNA in WT mice. Among these factors, expression of IL-13 and MCP-1 mRNA was further enhanced in IL-6-deficient mice, compared with WT mice. However, both WT and IL-6-deficient mice exhibited similar levels of airway responsiveness to increasing doses of methacholine, even after repeated exposure to OVA.

CONCLUSION

These results suggest that IL-6 has dual roles in the chronic phase of asthma: down-regulation of inflammatory cell infiltration and enhancement of airway remodelling.

Constipation, laxative use and risk of colorectal cancer: The Miyagi Cohort Study

The objective of this study was to investigate the association between constipation or laxative use and the risk of colorectal cancer in Japanese men and women. In 1990, we delivered a self-administered questionnaire to 41670 subjects who were 40-64 years old. During the seven years of follow-up, 251 incident cases of colorectal cancer were documented. Constipation was defined as a bowel movement frequency of less than daily. The multivariate relative risk (RR) of colorectal cancer for constipated subjects compared with those with daily bowel movements was 1.35 (95% Confidence Interval: 0.99-1.84). The RR for laxative users over non-users was 1.31 (0.88-1.95), and for frequent users (twice a week or more) it was 2.75 (1.48-5.09). When colorectal cancers were divided into colon cancers or rectal cancers, a significant association was found with colon cancer alone. Our results support the hypothesis that constipation or laxative use increases the risk of colon cancer.

Synthesis and microstructural analysis of Si3N4 nanorods

Alpha-Si3N4 nanorods with 20-80 nm width were synthesized by carbothermal reduction of SiO with amorphous activated carbon (AAC) as a reductant. Microstructural characterization of the synthesized nanorods was carried out by high resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray analysis. Many Si3N4 nanorods were found to be twisted. Each twisted nanorod contained several straight Si3N4 parts. The straight parts had the rod axes orientated along the (1010) direction, which is the closest packing direction of alpha-Si3N4. There were two kinds of joints between the two adjacent straight Si3N4 parts. Formation mechanism of the Si3N4 nanorods is discussed.

Effects of suplatast tosilate, a new type of anti-allergic agent, on airway cough hypersensitivity induced by airway allergy in guinea-pigs

BACKGROUND

Cough receptor hypersensitivity is a fundamental feature of some conditions presenting with chronic non-productive cough. Suplatast tosilate, an anti-allergic agent, is a T helper (Th)2 cytokine inhibitor that inhibits the synthesis of interleukin (IL)-4, IL-5, immunoglobulin (Ig)E production, and local eosinophil accumulation.

OBJECTIVE

The purpose of this study was to investigate the effect of suplatast on antigen-induced airway cough hypersensitivity and eosinophil infiltration into the airway.

METHODS

Number of coughs elicited by inhalation of increasing concentrations of capsaicin (10-8, 10-6 and 10-4 M) was counted 24 h after an antigen challenge in conscious guinea-pigs and then bronchoalveolar lavage was performed. We investigated the effect of single (before antigen challenge or capsaicin provocation) or repetitive treatment with intraperitoneal suplatast at a dose of 10 or 30 mg/kg on antigen-induced cough hypersensitivity.

RESULTS

Twenty-four hours after antigen challenge, guinea-pigs developed an increase in cough receptor sensitivity to inhaled capsaicin and eosinophil infiltration in the airways. After a 2-week treatment with suplatast, but not after only a single treatment before antigen challenge or capsaicin provocation, the antigen-induced early phase bronchoconstriction, cough hypersensitivity, and airway eosinophilia were inhibited in a dose-dependent manner.

CONCLUSION

These results indicate that suplatast inhibits airway cough hypersensitivity underlying allergic eosinophilic inflammation.

Role of the cytoskeleton in mediating cAMP-dependent protein kinase inhibition of the epithelial Na+/H+ exchanger NHE3

The Na(+)/H(+) exchanger NHE3 isoform mediates the entry of Na(+) into epithelial cells of the kidney and gastrointestinal tract. Hormones and pharmacological agents that activate cAMP-dependent protein kinase A (PKA) are potent inhibitors of native and ectopically expressed NHE3 in epithelial and Chinese hamster ovary AP-1 cells, respectively. Previous studies have shown that acute inhibition is coupled to direct phosphorylation of the exchanger, but this only partly accounts for the observed effects. In this report, we show that inhibition of NHE3 activity by forskolin, an activator of adenylate cyclase, occurs without changes in surface expression of the exchanger but is associated with altered cytoskeletal structure. This effect resembles that obtained with cytochalasin D or latrunculin B, actin disrupting agents that also inhibit NHE3. Such similarities prompted us to further investigate the relationship between PKA-induced inhibition of the exchanger and changes in the actin cytoskeleton. Inhibition of NHE3 by cytochalasin D does not require PKA, because the inhibitory effect is preserved in a mutant NHE3 that is not phosphorylated by PKA and in cells pretreated with the PKA inhibitor H89. In contrast, involvement of actin in the effect of cAMP on the exchanger is supported by the following observations: (i) jasplakinolide, an F-actin stabilizer, prevents the inhibition caused by forskolin, and (ii) constitutively active forms of RhoA and Rho kinase interfere with actin disruption by forskolin and also decrease inhibition of the transporter. These results suggest that reorganization of the cytoskeleton by PKA is involved in mediating inhibition of NHE3.

Effects of oral steroids on blood CXCR3+ and CCR4+ T cells in patients with bronchial asthma

Corticosteroids are widely used in bronchial asthma, but their mechanism of action is not fully understood. The in vitro studies have proposed that human T helper cells, type 1 (Th1) favor expression of CXCR3, whereas Th2 cells favor CCR4. In this study we investigated whether oral prednisolone modulates the balance of peripheral blood CXCR3+ and CCR4+ T cells. We analyzed the T-cell subsets in 28 patients with stable atopic asthma and 13 normal control subjects before and after 2 wk of treatment with prednisolone, 20 mg/d, or placebo in a randomized, double-blind, parallel group study. The numbers of CXCR3+ and CCR4+ memory T cells were measured with a flow cytometer, and expressed as percentages in CD4+/CD45RO+ memory T cells. In the steroid-treated asthma group, there was a decrease in CCR4+ T cells (from 29.3% to 20.3%, p < 0.0001), and an increase in CXCR3+/ CCR4+ ratio (from 1.86 to 2.89, p = 0.0047), whereas there was no change in CXCR3+ T cells. However, the percentages of CCR4+ cells did not change after steroid therapy in normal control subjects. These results suggest that short-term oral corticosteroid modulates the balances of CXCR3+ and CCR4+ cells in patients with asthma.

Temperature dependency of radiation damage in inorganic materials by 300 keV electrons

Temperature dependency of radiation damage in albite and natrolite was studied quantitatively by measuring the diffraction intensity with imaging plates. Radiation damage was reduced at low temperature in albite but was enhanced in natrolite. A damage process model, in which creation and annihilation of localized defects were considered, was proposed. According to this model, Boltzmann factor in temperature dependency is dominated by a difference between energy for diffusion of the localized defects and energy for breakdown of a crystal framework. When the diffusion energy is larger than breakdown energy, the activation energy in Boltzmann factor seems to be effectively negative.

Effects of carbocysteine on antigen-induced increases in cough sensitivity and bronchial responsiveness in guinea pigs

Carbocysteine is a mucoactive drug and is being used for both acute and chronic infectious airway diseases. Although carbocysteine can repair the damage of epithelial cells caused by exposure to various agents, the effects of this agent on allergic airway diseases such as asthma and eosinophilic bronchitis with an isolated chronic cough, in both of which epithelial damage may be characteristic, is not clear. We investigated the effects of carbocysteine on antigen-induced cough hypersensitivity to inhaled capsaicin at 48 h and bronchial hyperresponsiveness to inhaled methacholine at 72 h after challenge with an aerosolized antigen in actively sensitized guinea pigs. After measuring bronchial responsiveness, we examined neutral endopeptidase (NEP) activity in the tracheal tissue. Carbocysteine (10, 30, or 100 mg/kg) was given intraperitoneally every 12 h for 3 days after antigen challenge. The number of coughs elicited by an aerosol of capsaicin (10(-4) M) was significantly (p < 0.01) decreased in carbocysteine groups (6.13 +/- 0.59 at 10 mg/kg, 4.88 +/- 0.67 at 30 mg/kg, and 4.50 +/- 0.33 at 100 mg/kg during 3 min measurement) compared with the control group (9.75 +/- 0.53). Furthermore, carbocysteine dose dependently repaired the antigen-induced decrease of NEP activity in the tracheal tissue, but it did not influence the bronchial hyperresponsiveness or bronchoalveolar lavage cell component. These findings suggest that carbocysteine promotes the repair of damaged epithelium by allergic reaction and may be useful in allergic airway diseases accompanied by isolated chronic coughing, especially eosinophilic bronchitis without asthma and tracheobronchitis with cough hypersensitivity.

Nanotubes of boron nitride filled with molybdenum clusters

Carbon nanotubes are known to be metallic or semiconducting, depending on their helicity and diameter. However, boron nitride (BN) nanotubes are the only nanotubular product known to date that are predicted to have stable insulating properties that are independent of their atomic structure and morphology. Thus, the BN tube has attracted prime attention as an advanced nanoinsulating shield for all types of encapsulated conducting material, i.e., metal wires, clusters, etc. However, so far there have been no successes in controlled one-dimensional filling of BN nanotubes with conductive material. We report the first experimental results on the synthesis, high-resolution transmission electron microscopy, energy dispersion X-ray analysis, and electron energy loss spectroscopy of BN nanotubes that are filled with Mo clusters over their entire length. This was accomplished by means of two-step thermochemical treatment of chemically vapor-deposited C nanotubes with B2O3, CuO, and MoO3 oxides in a flowing N2 atmosphere. The first examples of BN nanotubes filled with molybdenum clusters are reported and the formation of the first nanocable (approximately 10 nm in length), consisting of a conductive metal core and an insulating BN nanotubular shield is demonstrated.

Connexin 26 distribution in gap junctions between melanocytes in the human vestibular dark cell area

We have previously demonstrated the presence of gap junctions between melanocytes in the human vestibular organ and have speculated that melanocytes function in maintaining the homeostasis of the microenvironment of the inner ear. The purpose of the present study was to characterize the expression and ultrastructural localization of connexin (Cx) protein in melanocytes of the human vestibular organs. Surgical material was obtained from patients operated on for vestibular schwannoma and was processed for light microscopy, confocal laser scanning microscopy, conventional TEM, and immuno TEM. The specimens were labeled with anti-Cx26, Cx32, and Cx43 antibodies and examined by light microscopy. Specimens were also labeled with anti-Cx26 antibody and examined by laser microscopy and immuno-TEM methods. The specimens examined in this study were mainly dark cell areas from the human vestibular organ, whose epithelial and subepithelial layers are rich in melanocytes. Light-microscopic immunohistochemical studies showed positive labeling for Cx26 protein between subepithelial melanocytes, and Cx32 was also detected. Use of anti-Cx26 antibody and confocal laser scanning microscopy revealed high levels of Cx26 around the subepithelial melanocytes. Post-embedding immuno-gold transmission electron microscopy showed significant aggregation of gold particles (33.97 +/- 8.01% of total gold particles) around the gap junctions of the subepithelial melanocytes. The results of this study indicated that melanocytes are connected through gap junctions that mainly contain Cx26. This suggested that the melanocytes in the human vestibular organ may play a role in transporting material between the endolymph and perilymph.

Blockade of eosinophil migration and airway hyperresponsiveness by cPLA2-inhibition

We examined the role of a cytosolic phospholipase A2 (cPLA2) in antigen-induced eosinophil infiltration of airways and in airway hyperresponsiveness to methacholine. Inhibition of cPLA2, or blockade of the platelet-activating factor (PAF) receptor, blocked antigen-induced airway hyperresponsiveness and suppressed eosinophil infiltration. Neither cyclooxygenase nor 5-lipoxygenase inhibition had either effect. We show here that, in antigen-sensitized guinea pigs, cPLA2 inhibition prevents both eosinophilic infiltration and subsequent airway hyperresponsiveness after antigen challenge. We also show that this effect is mediated by first-step hydrolysis of membrane phospholipid into lysophospholipid rather than by prostanoid or leukotriene metabolites of arachidonate.

Perilymph fistula--45 case analysis

PURPOSE OF THE STUDY

Though perilymph fistula (PLF) is not a rare disease, preoperative diagnosis still remains to be established. Some new diagnostic methods are challenging, but there is still no established diagnostic method except exploratory tympanotomy that verifies the occurrence of leakage. Early diagnosis of PLF is fully depending on history taking and some clinical examinations. To know the clinical features of PLF is one of the greatest helps to make both earlier and accurate diagnosis. In spite of some innovations in clinical examinations classic diagnostic procedure is thought to be still reliable.

PROCEDURES

We investigated the clinical symptoms, basic tests results and therapeutic results in patients with PLF.

RESULTS

From 1983 to 1998 PLF was identified in 44 patients (45 ears) with exploratory tympanotomies in our hospital. With respect to clinical history the predisposing factors such as blowing the nose, lifting heavy goods, and landing in an airplane were found in almost half of the patients, while the rest of them had no clear inducing factors. Their major symptoms included hearing loss (93%), vertigo and dizziness (91%), tinnitus (76%), and aural fullness (31%). The patients who have a clear predisposing factor tended to make diagnosis easily; on the other hand the rest of the patients who do not have clear etiology had some diagnostic difficulty. Subjective positive fistula signs were observed in 71% of patients. Vestibular symptoms improved in 80% of patients after closure of PLF.

CONCLUSIONS

These results suggest that the variety of clinical manifestation make diagnosis more difficult. At the moment meticulous clinical history taking and close follow-up applying repeating fistula tests are the most important for not only earlier but also accurate diagnosis.

RhoA and rho kinase regulate the epithelial Na+/H+ exchanger NHE3. Role of myosin light chain phosphorylation

The activity of the Na(+)/H(+) exchanger NHE3 isoform, which is found primarily in epithelial cells, is sensitive to the state of actin polymerization. Actin assembly, in turn, is controlled by members of the small GTPase Rho family, namely Rac1, Cdc42, and RhoA. We therefore investigated the possible role of these GTPases in modulating NHE3 activity. Cells stably expressing NHE3 were transiently transfected with inhibitory forms of Rac1, Cdc42, or RhoA and transport activity was assessed using microfluorimetry. NHE3 activity was not adversely affected by either dominant-negative Rac1 or Cdc42. By contrast, the inhibitory form of RhoA greatly depressed NHE3 activity, without noticeably altering its subcellular distribution. NHE3 activity was equally reduced by inhibiting p160 Rho-associated kinase I (ROK), a downstream effector of RhoA, with the selective antagonist Y-27632 and a dominant-negative form of ROK. Furthermore, inhibition of ROK reduced the phosphorylation of myosin light chain. A comparable net dephosphorylation was achieved by the myosin light chain kinase inhibitor ML9, which similarly inhibited NHE3. These data suggest that optimal NHE3 activity requires a functional RhoA-ROK signaling pathway which acts, at least partly, by controlling the phosphorylation of myosin light chain and, ultimately, the organization of the actin cytoskeleton.

Effect of losartan, a type 1 angiotensin II receptor antagonist, on bronchial hyperresponsiveness to methacholine in patients with bronchial asthma

It is unclear whether angiotensin II receptors are involved in bronchial hyperresponsiveness in asthmatic patients. We examined the effect of losartan, a specific angiotensin II type 1 (AT1) receptor antagonist, on bronchial responsiveness to inhaled methacholine in eight patients with stable asthma. Bronchial responsiveness to methacholine, assessed as the concentration of methacholine producing a 20% fall in FEV(1) (PC(20)-FEV(1)) and a 35% fall in standardized partial expiratory flow at 40% of FVC (PC(35)-PEF(40)), was measured on two occasions 2 wk apart. Losartan (50 mg once a day) or a placebo was orally administered for 1 wk before methacholine provocation test in a double-blind, randomized, crossover fashion. Although the PC(20)-FEV(1) values after placebo (2.037 [geometric standard error of the mean, GSEM = 0.210] mg/ml) and losartan (2.098 [GSEM, 0.239] mg/ml) were identical (p = 0.840), the geometric mean PC(35)-PEF(40) values significantly (p = 0.034) increased from 0.258 (GSEM, 0.156) mg/ml with placebo to 0.456 (GSEM, 0.186) mg/ml with losartan. We conclude that AT1 receptors are involved in bronchial hyperresponsiveness in asthmatic patients. This is the first report demonstrating the involvement of AT1 receptors in bronchial asthma.

Type 1 angiotensin II receptor antagonism reduces antigen-induced airway reactions

Although the renin-angiotensin system is activated in patients with asthma during severe acute attacks and angiotensin II has been shown to cause bronchoconstriction in patients with asthma, the role of angiotensin II in patients with asthma is unclear. We investigated the effects of two specific antagonists at type 1 and type 2 angiotensin II receptors, candesartan cilexetil (TCV-116) and PD123319, on antigen-induced airway reactions in guinea pigs. Sixty minutes after intraperitoneal administration of candesartan cilexetil (0.1, 1.0, or 10 mg/kg) or PD123319 (30 mg/kg), animals received an antigen challenge. Airway responsiveness to inhaled methacholine was assessed as the dose of methacholine required to produce a 200% increase in the pressure at the airway opening (PC(200)). Differential cell counts in bronchoalveolar lavage fluids (BALF) were measured 24 h after antigen challenge. Candesartan cilexetil did not inhibit antigen-induced bronchoconstriction in sensitized guinea pigs or alter PC(200) in nonsensitized guinea pigs. Antigen inhalation significantly increased bronchoconstrictor responses to methacholine and increased airway accumulation of eosinophils; both responses showed dose-dependent prevention by candesartan but not by PD123319. These results indicate that endogenous angiotensin II promotes antigen-induced airway hyperresponsiveness and eosinophil accumulation by acting at type 1 receptors.

Effect of aerosolized administration of KF19514, a phosphodiesterase 4 inhibitor, on bronchial hyperresponsiveness and airway inflammation induced by antigen inhalation in guinea-pigs

BACKGROUND

Although phosphodiesterase (PDE) 3 and 4 inhibitors have received much attention for the treatment of bronchial asthma, systemic adverse effects have also been reported.

OBJECTIVE

The purpose of this study was to investigate the effect of inhaled olprinone, a newly developed PDE3 inhibitor, and KF19514, a PDE1 and 4 inhibitor, on antigen-induced airway reactions in guinea-pigs.

METHODS

Fifteen minutes after inhalation of olprinone (0.1 or 1.0 mg/mL) and KF19514 (0.1 or 0.01 mg/mL), animals were given an antigen challenge. Bronchial hyper-responsiveness and bronchoalveolar lavage fluid cell analysis were performed 24 h after the antigen challenge.

RESULTS

Inhalation of olprinone and KF19514 caused a dose-related inhibition of antigen-induced bronchoconstriction. Antigen inhalation significantly increased bronchoconstrictor responses to methacholine, and airway accumulation of neutrophils and eosinophils, 24 h after the antigen challenge. These responses were dose-dependently prevented by KF19514, but not by olprinone.

CONCLUSION

The results indicate that inhaled PDE inhibitors might be useful for treatment of bronchial asthma.

(R)-ACX is a novel sufonylurea compound with potent, quick and short-lasting hypoglycemic activity

We investigated the mechanism of the hypoglycemic effect of (R)-4-(1-acetoxyethyl)-N-(cyclohexylcarbamoyl)benzene-sulfonamide [(R)-acetoxyhexamide; (R)-ACX], a new sulfonylurea compound. (R)-ACX potently stimulated the release of insulin from cultured pancreatic beta-cells (HIT T15 cells), established from hamster islet cells SV40-transformed. When (R)-ACX was orally administered to fasted rats, it decreased the plasma glucose level in a dose-dependent manner. The hypoglycemic effect of (R)-ACX was quick and short lasting, as compared to that of acetohexamide and glibenclamide. The quick and short-lasting hypoglycemic effect of (R)-ACX was thought likely to result from rapid absorption of (R)-ACX and rapid elimination of (R)-ACX and its metabolite, (R)-hydroxyhexamide. Furthermore, (R)-ACX was found to suppress the increase of blood glucose level due to starch loading in fasted mice. (R)-ACX may be useful in the control of postprandial hyperglycemia to patients with non-insulin-dependent diabetic mellitus.

The microstructural analysis of SiC nanorods by high-resolution electron microscopy

Beta-SiC nanorods have been synthesized by the reaction of SiO and carbon nano-capsules. For the synthesis of SiC nanorods, it was examined that the reaction temperature and the ratio of SiO to carbon nanocapsules are important and the most appropriate temperature and ratio are around 1380 degreesC and 5:2, respectively. The synthesized SiC nanorods were characterized by high-resolution electron microscopy. Most of the SiC nanorods are straight and have the diameter of 30-150 nm while the SiC tips of the SiC nanorods have the size 100-400 nm. The SiC nanorods have many stacking faults normal to the [111] direction. Each SiC nanorod has one kind of preferential axis direction, which is either parallel or normal to the [111] direction. Based on the microstructural analysis of the SiC nanorods, a possible growth mechanism of the SiC nanorods is proposed.

The apical Na(+)/H(+) exchanger isoform NHE3 is regulated by the actin cytoskeleton

The epithelial isoform of the Na(+)/H(+) exchanger, NHE3, associates with at least two related regulatory factors called NHERF1/EBP50 and NHERF2/TKA-1/E3KARP. These factors in addition interact with the cytoskeletal protein ezrin, which in turn binds to actin. The possible linkage of NHE3 with the cytoskeleton prompted us to test the effect of actin-modifying agents on NHE3 activity. Cytochalasins B and D and latrunculin B, which interfere with actin polymerization, induced a profound inhibition of NHE3 activity. The effect was isoform-specific inasmuch as the "housekeeping" exchanger NHE1 was virtually unaffected. Cytoskeletal disorganization was associated with a subcellular redistribution of NHE3, which accumulated at sites where actin aggregated, suggesting a physical interaction of exchangers with the cytoskeleton. An interaction was further suggested by the co-sedimentation of a detergent-insoluble fraction of NHE3 with the actin cytoskeleton. Inhibition of transport was not due to diminution in the number of transporters at the plasmalemma. Functional analyses of NHE1/NHE3 chimeras revealed that the cytoplasmic domain of NHE3 conferred sensitivity to cytochalasin B. Progressive carboxyl-terminal and internal deletions of the cytoplasmic region of NHE3 indicated that the region between residues 650 and 684 is critical for this response. This region overlaps with the domain reported to interact with NHERF and also contains a putative ezrin-binding site; hence, it likely plays a role in interactions with the cytoskeleton.

Enzymatic synthesis of (-)- and (+)-acetoxyhexamides and (-)- and (+)-hydroxyhexamides

The enantioselective hydrolysis of (+/-)-4-(1-acetoxyethyl)-N-(cyclohexylcarbamoyl)-benzenesulfona mides 3 with lipase Amano P from Pseudomonas sp. in a water-saturated solvent gave (R)-4-(1-hydroxyethyl)-N-(cyclohexylcarbamoyl)benzenesulfonamide 2 (39%, > 99% ee) and unchanged (S)-3 (50%, 62% ee). On the other hand, enantioselective esterification of (+/-)-2 with lipase Amano P in the presence of vinyl acetate provided (R)-3 (41%, > 99% ee) and unchanged (S)-2 (46%, 78% ee).

Long-term prognosis of profound facial nerve paralysis secondary to acoustic neuroma resection

The long-term prognosis of profound facial nerve paralysis was reviewed in 107 patients who, despite preserved nerve continuity, showed no facial movement after acoustic neuroma resection. Spontaneous recovery occurred in 77 patients. However, there was no apparent recovery in 30 patients. Twenty-two of these patients underwent hypoglossal-facial nerve anastomosis 7-33 months after tumor resection. When spontaneous recovery occurred, the first sign of remission was observed between 3 and 4 months after surgery in nearly half of the patients. Such a sign did not appear after 12 months. The recovery of facial movement deteriorated depending on how long remission onset was delayed. However, the quality of facial movement in patients with such delayed remission was still identical or better than that in those after hypoglossal-facial nerve anastomosis. These results showed that hypoglossal-facial nerve anastomosis should be performed approximately 1 year after tumor resection if no sign of remission has been observed by then.

Endosomal recycling of the Na+/H+ exchanger NHE3 isoform is regulated by the phosphatidylinositol 3-kinase pathway

The NHE3 isoform of the Na+/H+ exchanger localizes to both the plasmalemmal and endosomal compartments in polarized epithelial and transfected Chinese hamster ovary (AP-1) cells. It is unclear how the distribution of NHE3 between these compartments is regulated. In this study, we examined the potential involvement of phosphatidylinositol 3'-kinase (PI3-K) in regulating the activity and distribution of NHE3, as this lipid kinase has been implicated in modulating vesicular traffic in the endosomal recycling pathway. Wortmannin and LY294002, both potent inhibitors of PI3-K, markedly inhibited NHE3-mediated H+ extrusion across the plasma membrane in a concentration- and time-dependent manner. The subcellular distribution of the antiporters was monitored by transfecting epitope-tagged NHE3 into AP-1 cells. In parallel with the inhibition of transport, PI3-K antagonists induced a pronounced loss of NHE3 from the cell surface and its accumulation in an intracellular compartment, as assessed by immunofluorescence microscopy and enzyme-linked immunosorbent assays. Further analysis using cells transfected with antiporters bearing an external epitope tag revealed that the redistribution reflected primarily a decrease in the rate of recycling of intracellular NHE3 to the cell surface. The wortmannin-induced inhibition and redistribution of NHE3 were prevented when cells were incubated at 4 degreesC, consistent with the known temperature dependence of the endocytic process. These observations demonstrate that NHE3 activity is controlled by dynamic endocytic and recycling events that are modulated by PI3-K.

Bafilomycin A1 induces apoptosis in the human pancreatic cancer cell line Capan-1

Bafilomycin A1, a specific inhibitor of vacuolar type H(+)-ATPase, can inhibit the growth of a variety of cultured cells in a dose-dependent manner, but its mechanism is unclear. The aim of this study was to examine whether bafilomycin A1 inhibits the growth of Capan-1 human pancreatic cancer cells through apoptosis. The effect of bafilomycin A1 on tumour growth in vitro and in vivo was examined using an MTT assay and an in vivo tumour model. The presence or absence of apoptosis was determined by morphology and DNA analysis of tumour cells. The concentration of bafilomycin A1 for 50 per cent inhibition of cell viability during 72 h by the MTT assay was 5 nm. In DNA analysis, a ladder of fragmented DNA was detected in Capan-1 cells treated with bafilomycin A1 at concentrations greater than 10 nm for 24 h. Nude mice bearing a xenografted Capan-1 cell line tumour received 4 weeks of bafilomycin A1 (1.0 mg/kg per day). This treatment significantly inhibited tumour growth compared with controls after 21 days (P < 0.05). Histopathological examination of tumour cells in the treated group demonstrated signs of apoptosis with chromatin condensation and cell shrinkage. These observations suggest that bafilomycin A1 inhibits the growth of Capan-1 human pancreatic cancer cells through apoptosis.

Identification of sites required for down-regulation of Na+/H+ exchanger NHE3 activity by cAMP-dependent protein kinase. phosphorylation-dependent and -independent mechanisms

We recently identified a region within the cytoplasmic C-terminal tail of the Na+/H+ exchanger NHE3 isoform (residues 579 to 684) which is essential for inhibition of transport activity by cAMP-dependent protein kinase (PKA) (Cabado, A. G., Yu, F. H., Kapus, A., Gergely, L., Grinstein, S., and Orlowski, J. (1996) J. Biol. Chem. 271, 3590-3599). To further define determinants of PKA regulation, six serine residues located in potential recognition sequences for PKA within, or adjacent to, this region (positions 552, 605, 634, 661, 690, and 691) were altered either independently or in various combinations using site-directed mutagenesis. Wild type and mutant NHE3s tagged with the influenza virus hemagglutinin epitope were stably expressed in exchanger-deficient Chinese hamster ovary cells (AP-1) for functional studies. Of the individual mutations examined, only substitutions at Ser605 or Ser634 affected sensitivity to forskolin, an activator of adenylate cyclase, although partial inhibition of NHE3 activity by forskolin remained. By contrast, simultaneous mutation of both these serines completely abolished cAMP-mediated inhibition of NHE3 without greatly affecting basal transport activity. Two-dimensional analysis of tryptic digests of immunoprecipitated NHE3 labeled in vivo with [32P]orthophosphate revealed several phosphopeptides under basal conditions. Phosphorylation was increased approximately 3-fold in one of these peptides following forskolin treatment, and this change was eliminated by mutation of residue Ser605. Thus, phosphorylation of Ser605 is essential for cAMP-mediated inhibition of NHE3. In addition, Ser634 is also required for the effect of cAMP, even though this residue does not become phosphorylated upon activation of PKA.

Elevated chemokine levels in bronchoalveolar lavage fluid of tuberculosis patients

In pulmonary tuberculosis, the proportion of lymphocytes, particularly that of CD4+ T lymphocytes, was increased in bronchoalveolar lavage fluid (BALF), reflecting their protective role against mycobacterial infections. In order to elucidate the mechanisms of lymphocyte accumulation in lungs, we measured the levels of chemokines with potent lymphocyte chemotactic activities, including interleukin-8 (IL-8), monocyte chemoattractant protein-1 (MCP-1), and, regulated on activation, normal T-cell expressed and secreted (RANTES) present in BALF from patients with pulmonary tuberculosis in acute (n = 10) and convalescent phases (n = 6), as well as normal subjects (n = 10). During the acute phase of the disease, the proportions of lymphocytes and neutrophils were increased, as reported in previous studies. The levels of IL-8, MCP-1, and RANTES in the acute phase of pulmonary tuberculosis were also markedly elevated as compared with those of normal subjects. MCP-1 and RANTES, but not IL-8 levels present in BALF, decreased in the convalescent phase. Moreover, the concentration of RANTES correlated significantly with the absolute number of CD4+ cells in BALF. These data suggest that chemotactic cytokines are differentially produced and participate in the host response to Mycobacterium tuberculosis infection.

Surface activity of sputum from acute asthmatic patients

The cause of airway resistance that develops during an asthma attack is not fully understood. Besides bronchospasm and airway edema, a surfactant dysfunction has been suggested as a reason for an increase in airway resistance. This study sought to determine if surface activity of airway fluid is altered in acute asthmatic attacks. Sputa were collected serially from seven patients with acute asthmatic attacks and compared with that of normal subjects (n = 15) and subjects with stable asthma (n = 14). Sputa were analyzed for minimal surface tension (STmin), phospholipids (PL), and total proteins (TP). There were no significant differences in STmin, PL, and TP between sputa from normal subjects and subjects with stable asthma. In the acute phase of the attack, TP, TP/PL ratio, and STmin significantly increased. However, in the recovery phase of the attack, TP/PL ratio and STmin significantly decreased. These data demonstrated that surface properties of airway fluid deteriorated in the early phase of the asthma attack, but were ameliorated in the recovery phase possibly by the surfactant recruitment. The drastic changes in surface activity of sputum suggest that changes in airway surfactant may be partly involved in the pathogenesis of the airway obstruction during asthmatic attack.

Effect of surfactant inhalation on allergic bronchoconstriction in guinea pigs

BACKGROUND

In the small airway, surfactant reduces surface tension, prevents liquid filling of bronchioles, thereby maintaining patency in the small airways. Recent reports demonstrated that surfactant dysfunction develops in experimental asthma in immunized guinea pigs. However, there are few reports concerning surfactant and lung function in an experimental asthma model.

OBJECTIVE

To examine whether inhaled surfactant improves lung mechanics in antigen-induced bronchoconstriction in guinea pigs.

METHOD

We developed a passively immunized guinea pig model for allergic bronchoconstriction induced by antigen inhalation. Using this model, we investigated the effect of inhaled exogenous surfactant, surfactant TA, on the airway opening pressure (Pao) after antigen challenge.

RESULTS

Aerosol antigen challenge produced a gradual and long-lasting increase in Pao. Twenty minutes after antigen challenge, aerosolized surfactant TA, 20 mg/ml, was inhaled for 90 s, and it significantly reduced the Pao by 32.8% in 12 min, while a 10.2% reduction was observed in a control group in the same period. When surfactant TA was administered by 90-s inhalation before antigen challenge, it inhibited the Pao increase in a dose-dependent manner: mean inhibitory rates of Pao were 33.6% in surfactant TA 10 mg/ml and 61.9% in surfactant TA 20 mg/ml, respectively.

CONCLUSION

Inhaled surfactant showed preventive and recovery effects on antigeninduced bronchoconstriction in an immunized guinea pig model.

A specific elevation of RANTES in bronchoalveolar lavage fluids of patients with chronic eosinophilic pneumonia

Chronic eosinophilic pneumonia (CEP) is a rare, idiopathic lung disorder characterized pathologically by massive eosinophil infiltration into lung. In the bronchoalveolar lavage fluid (BALF) of patients with CEP, eosinophil numbers were markedly increased but returned to normal-levels upon the resolution of clinical symptoms, which suggests the crucial role of eosinophils in the pathogenesis of CEP. To clarify the mechanism of eosinophil accumulation in CEP, we determined the BALF levels of RANTES and macrophage inflammatory protein-1 alpha, two chemokines that predominantly exhibit in vitro eosinophil chemotactic activities. RANTES (106.7 +/- 27.2 pg/mg albumin; n = 16) concentrations in BALF from patients with CEP were significantly elevated in comparison with those of normal control subjects (1.4 pg/mg albumin; n = 13), whereas BALF macrophage inflammatory protein-1 alpha levels were not. In addition, eosinophils, lymphocytes, and macrophages in BALF were positively stained with a specific anti-RANTES antibody, which suggests that RANTES was produced locally in the lungs of CEP patients. Moreover, BALF-RANTES levels correlated significantly with the proportion of eosinophils in BALF. Furthermore, nearly half of the eosinophil chemotactic activities in BALF were abrogated by the anti-RANTES antibody in vitro. Collectively, these data suggest that locally produced RANTES is involved in eosinophil accumulation in the pulmonary alveolus and interstitium of patients with CEP.

The role of vacuolar H(+)-ATPase in the control of intragranular pH and exocytosis in eosinophils

The presence of vacuolar H(+)-ATPase (V-ATPase) on exocytotic granules in eosinophils and the role of this enzyme in exocytosis were explored in this study. Antibody against 116-kd subunit of V-ATPase positively stained eosinophil granules in immunofluorescence analysis. When eosinophil lysate was extracted immunomagnetically with the same antibody, the extracted fraction contained a considerable amount of eosinophil peroxidase, a marker of eosinophil-specific granules, which indicates that V-ATPase was present on the membranes of eosinophil exsosomal granules. The pH of the eosinophil granules, measured fluorometrically with acridine orange as a delta pH-sensitive dye, was estimated to be 5.1. The acidity of the eosinophil granules was perturbed by bafilomycin A1, a potent selective inhibitor of V-ATPase, which indicates that the low pH of these granules is maintained by V-ATPase activity. BafilomycinA1 and NH4Cl, both of which raise the intragranular pH to neutral, inhibited the eosinophil peroxidase exocytosis induced by platelet-activating factor. These agents did not, however, affect the changes in cytosolic free calcium concentration [Ca2+]i induced by platelet-activating factor. These observations suggest that bafilomycin A1 inhibited a delta pH-requiring step in eosinophil exocytosis that was preceded by the [Ca2+]i transient in the signal transduction pathway, and, hence, the findings suggest the pivotal role of V-ATPase in maintaining intragranular pH and its function of eosinophil exosomal granules.

Increase of chemokine levels in sputum precedes exacerbation of acute asthma attacks

Basophils and eosinophils can be activated in vitro by several chemokines such as RANTES, monocyte chemotactic and activating factor (MCAF/MCP-1), macrophage inflammatory peptide-1 alpha (MIP-1 alpha), and interleukin-8 (IL-8). To explore the clinical relevance of the in vitro observations, we measured here the concentrations of these chemokines in sputa from asthmatic patients during acute attacks. Before the onset of a late-phase exacerbation, sputum MCAF/MCP-1, MIP-1 alpha, and IL-8 levels transiently but markedly increased from the basal levels in all of the patients with exacerbation, whereas the sputum levels of these chemokines remained unchanged during the course in the patients without a late-phase exacerbation. These results suggest the involvement of these chemokines in the late-phase exacerbation of asthma.

Effect of thromboxane A2 synthetase inhibitor, OKY-046, on sputum in chronic bronchitis and diffuse panbronchiolitis

The mechanisms of excessive sputum production are only partially understood. We speculated that a selective thromboxane (Tx) A2 synthetase inhibitor, OKY-046, now used in the treatment of asthma in Japan, could decrease excess sputum production in patients with chronic airways disease. To test this hypothesis, we carried out a double-blind, placebo-controlled study of the effects of OKY-046, administered orally at 400 mg.day-1, on the sputum of patients with chronic bronchitis and patients with diffuse panbronchiolitis. Patients treated with OKY-046 showed a significant decrease (22%) in sputum volume after 1 month, and a 39% decrease after 3 months. Although the rheological properties of the sputum and the concentrations of fucose and immunoglobulin (Ig) A in the sputum remained unchanged, significant decreases were observed in the concentrations of total protein, albumin, sialic acid and phospholipid. Since albumin and fucose are chemical markers of plasma exudation and mucus secretion, respectively, whilst sialic acid and phospholipid are derived both from serum and mucus, our results indicate that this TxA2 synthetase inhibitor reduced sputum volume by inhibiting microvascular leakage in the airway. OKY-046 may, therefore, be of value in the treatment of chronic bronchitis and diffuse panbronchiolitis.

Peripheral neuroectodermal tumor presenting pleural effusion

Pleural effusion is a common finding of peripheral neuroectodermal tumor (PNET) of the chest wall (Askin's tumor), but little is known about the characteristics. A case of Askin's tumor with pleural effusion is reported. Repeated cytologies were negative for malignancy, but levels of lactic dehydrogenase (LDH) and neuron-specific enolase (NSE) in the pleural effusion were increased. Surgical biopsy was performed and immunohistochemical study of the tumor revealed the diagnosis.

Inhibitory effect of aerosol administration of a sulfidopeptide leukotriene antagonist on bronchoconstriction induced by antigen inhalation in guinea pigs

The effects of inhalation of the sulfidopeptide leukotriene antagonist AS-35 (9-[(4-Acetyl-3-hydroxy-2-n-propyl-phenoxy)methyl]-3-(1H- tetrazol-5-yl)-4H-pyrido [1,2-a]pyrimidin-4-one, CAS 108427-72-1) on bronchoconstriction induced by aerosol antigen, histamine, and leukotriene C4, D4 (LTC4, D4) were investigated in anesthetized and artificially ventilated guinea pigs. The increase in pressure at the airway opening (P(ao)) was measured as an index representing the grade of bronchial response. The bronchoconstriction induced by aerosol antigen was suppressed dose-dependently by pretreatment with inhaled AS-35 (0.1 mg and 1 mg) through a pressurized meter-dosed inhaler in the passively sensitized animals pretreated with diphenhydramine hydrochloride. But the histamine-induced bronchoconstriction was not altered by the pretreatment with AS-35 inhalation. On the other hand, LTC4- and LTD4-induced bronchoconstriction was inhibited by the pretreatment with aerosol AS-35 in a dose-dependent manner. The deposited dose of inhaled AS-35 in the peripheral airways was 3.5 micrograms and 6.5 micrograms when 0.1 mg and 1 mg of the drug was inhaled, respectively. These results suggest that sulfidopeptide leukotrienes (s-LTs) play an important role in the allergic bronchoconstriction in guinea pigs pretreated with antihistamine, and AS-35 inhalation may be beneficial in the treatment of asthma.

Effect of inhaled procaterol on cough receptor sensitivity to capsaicin in patients with asthma or chronic bronchitis and in normal subjects

BACKGROUND

To evaluate the effect of inhaled beta 2 adrenergic agonists on the sensitivity of airway cough receptors, the effect of inhaled procaterol on cough induced by aerosolised capsaicin, a stimulant of C fibres, was studied in patients with asthma or chronic bronchitis and in normal subjects.

METHOD

Eleven patients with asthma and 10 with chronic bronchitis and 14 normal subjects participated. Increasing concentrations of capsaicin solution were inhaled for 15 seconds by tidal breathing through the mouth at one minute intervals until five or more coughs were elicited, before and 30 minutes after inhalation of 20 micrograms procaterol or placebo (freon gas alone) through a metered dose inhaler. Cough threshold was defined as the lowest concentration of capsaicin that elicited five or more coughs. To evaluate the bronchodilator effect of procaterol and the bronchoconstrictor effect of inhaled capsaicin, forced expiratory volume in one second (FEV1) was measured before and one minute after a capsaicin provocation test. This test was carried out both before and 30 minutes after treatment with procaterol or placebo.

RESULTS

The geometric mean value of cough threshold to capsaicin was significantly increased by procaterol and placebo in both groups of patients but not in the control subjects. The increment in the cough threshold was not significantly different between the treatments with procaterol and placebo in each group. FEV1 was significantly increased by procaterol but not by placebo in all three groups.

CONCLUSIONS

Inhaled procaterol has no effect on airway cough receptor sensitivity to capsaicin. The attenuation of the cough sensitivity seen after inhalation of procaterol in patients with asthma and bronchitis may result from tachyphylaxis to capsaicin.

[Analysis of bronchoalveolar lavage fluid in patients before and after bone marrow transplantation]

We analysed BALF cell findings in 9 patients (group A: 5 patients without lung disease after bone marrow transplantation (BMT), group B: 4 patients with lung disease after BMT) before and after BMT. Before BMT, BALF cell findings in group A were almost normal, whereas a relative increase of lymphocytes was seen in group B. Although total cell counts and cell composition in group A changed little after BMT, CD4/CD8 ratios in BALF lymphocytes decreased. In contrast, a relative increase of lymphocytes and neutrophils was seen in group B and there was variation of CD4/CD8 ratios in BALF lymphocytes after BMT. We there studied the BALF lymphocytes of 3 patients in group A and 4 patients in group B after BMT by means of 2-color analysis. Among CD4+ cell populations, CDw 29+ cells were decreased in both groups after BMT. A relative increase of BALF-CD4+ HLA-DR+ cells and CD8+ HLA-DR+ cells was seen in group A, but was not seen in group B. These findings suggest that there is abnormality of local immunity in the lung after BMT.

Thromboxane A2 synthetase inhibitor (OKY-046) improves abnormal mucociliary transport in asthmatic patients

The effect of a thromboxane A2 synthetase inhibitor (OKY-046, 400 mg po/day) on mucociliary transport was investigated in 19 asthmatic patients. The nasal clearance time, as measured by the saccharin test, was prolonged in asthmatics (60.2 +/- 8.4 SE min) compared with normal controls (15.1 +/- 3.4 SE min). Within 4 weeks after OKY-046 administration, the nasal clearance time had improved (27.4 +/- 4.4 SE min, P less than .01) and the amount of sputum had decreased 30% (P less than .01). These results indicate that thromboxane A2 plays an important role in mucociliary transport in patients with asthma.

[Inhibitory effects of rhIL-1 beta pretreatment on bleomycin-induced pneumonitis in mice]

We studied the effects of recombinant human interleukin-1 beta (rhIL-1 beta) pretreatment on bleomycin (BLM)-induced pneumonitis in mice. Lung injury was dose-dependently induced by BLM (50 mg/kg, 100 mg/kg, 150 mg/kg i.v.). The mice were pretreated with IL-1 (1 microgram/mouse i.p.) at 0.5, 6, 12 or 24 hours before the administration of BLM. Wet lung weight, lung weight-to-body weight ratio and bronchoalveolar lavage cell findings were analyzed with respect to time, and lung specimens on day 28 after administration of BLM were histopathologically examined. When mice were pretreated with IL-1 at 0.5 hr or 6 hr before the administration of BLM, changes in all the parameters were significantly suppressed. The results indicate that IL-1 pretreatment protects mice from BLM-induced pneumonitis and its effects are time-dependent.

MR and CT in the evaluation of sarcoid myopathy

Sarcoid myopathy is a relatively rare extrapulmonary complication of sarcoidosis. We evaluated the diagnostic utility of MR at 1.5 T in four patients with sarcoid myopathy of the lower extremities established by biopsy. Two of the patients were of the "atrophic type" and two of the "nodular type." The findings on MR were compared with the findings on CT, gallium scanning, and electromyography. Only MR was positive in all cases. The T2-weighted scans (spin echo 2,000/80) revealed two distinctly different patterns of abnormality (i.e., discrete foci of high signal intensity lesions in the patients with the nodular type of sarcoid myopathy and atrophic muscle of high signal intensity in the patients with the atrophic type). Due to its ability to provide objective findings of the extent and distribution of muscle involvement, MR should prove useful in the detection, diagnosis, and monitoring of sarcoid myopathy.

Activity of pulmonary surfactant after blocking the associated proteins SP-A and SP-B

To investigate the role of the pulmonary surfactant-associated proteins SP-A and SP-B, the respective monoclonal antibody (anti-A or anti-B) was added to porcine pulmonary surfactant at a weight ratio of 1:2, and the mixtures were tested on surfactant-deficient immature newborn rabbits (gestational age 26 days). Under pentobarbital sodium anesthesia and mechanical ventilation with a 25-cmH2O peak insufflation pressure, the tidal volumes of the animals given surfactant alone and of those given surfactant containing anti-A were 27.9 +/- 5.1 and 25.1 +/- 9.6 (SD) ml/kg, respectively, whereas that of those given surfactant with anti-B was 5.8 +/- 3.6 ml/kg (P less than 0.05). The surface adsorption times of surfactant alone and of anti-A-containing surfactant were less than 0.8 s compared with greater than 120 s (P less than 0.01) for anti-B-containing surfactant. The anti-B suppressed the surfactant activity until the weight ratio was decreased to 2:100. The role of SP-A could not be clarified, but it was concluded that SP-B is an essential factor for surfactant activity.

[A case of congenital bronchial atresia with obstructive pneumonia accompanied with partial anomalous pulmonary venous drainage]

A 25-year-old male was admitted with productive cough and an abnormal shadow on chest X-ray film which showed a cylindrical shadow near the left hilum and consolidation in the markedly hyperlucent left upper lung field. The cylindrical shadow appeared to be located in left S1+2 but bronchographic examination showed independence of the branches of B1+2. Furthermore, pulmonary venography by DSA showed that the left upper pulmonary vein entered the left brachiocephalic vein. The patient underwent left partial lobectomy under a diagnosis of congenital bronchial atresia with partial anomalous pulmonary venous drainage. Pathological examination of the resected lung revealed obstructive pneumonia in the over-inflated lung zone, probably induced through collateral airways.