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1.
Nutr Diabetes ; 6: e197, 2016 Feb 29.
Article de Anglais | MEDLINE | ID: mdl-26926588

RÉSUMÉ

OBJECTIVES: The prevalence of metabolic syndrome is increasing worldwide, especially in Asian populations. Early detection and effective intervention are vital. Plasma free amino acid profile is a potential biomarker for the early detection for lifestyle-related diseases. However, little is known about whether the altered plasma free amino acid profiles in subjects with metabolic syndrome are related to the effectiveness of dietary and exercise interventions. METHODS: Eighty-five Japanese subjects who fulfilled the Japanese diagnostic criteria for metabolic syndrome were enrolled in a 3-month diet and exercise intervention. The plasma free amino acid concentrations and metabolic variables were measured, and the relationships between plasma free amino acid profiles, metabolic variables and the extent of body weight reduction were investigated. Those who lost more than 3% of body weight were compared with those who lost less than 3%. RESULTS: Baseline levels of most amino acids in the subset that went on to lose <3% body weight were markedly lower compared with the counterpart, although both groups showed similar proportional pattern of plasma amino acid profiles. The weight loss induced by the diet and exercise intervention normalized plasma free amino acid profiles. For those with a high degree of weight loss, those changes were also associated with improvement in blood pressure, triglyceride and hemoglobin A1c levels. CONCLUSIONS: These data suggest that among Japanese adults meeting the criteria for metabolic syndrome, baseline plasma free amino acid profiles may differ in ways that predict who will be more vs less beneficially responsive to a standard diet and exercise program. Plasma free amino acid profiles may also be useful as markers for monitoring the risks of developing lifestyle-related diseases and measuring improvement in physiological states.


Sujet(s)
Acides aminés/sang , Syndrome métabolique X/sang , Perte de poids , Asiatiques , Glycémie/métabolisme , Pression sanguine , Indice de masse corporelle , Cholestérol HDL/sang , Analyse de regroupements , Régime amaigrissant , Exercice physique , Femelle , Hémoglobine glyquée/métabolisme , Humains , Insuline/sang , Japon , Mode de vie , Modèles linéaires , Mâle , Adulte d'âge moyen , Analyse multifactorielle , Prévalence , Triglycéride/sang , Tour de taille
2.
J Thromb Haemost ; 9(5): 922-7, 2011 May.
Article de Anglais | MEDLINE | ID: mdl-21294826

RÉSUMÉ

BACKGROUND: This study aimed to evaluate untreated, previous pulmonary thromboembolism (PE) in patients with acute fatal PE. PATIENTS AND METHODS: We studied 64 patients diagnosed as having died from acute PE by medico-legal autopsy. Previous PE was histologically confirmed on the basis of organized thrombi (OT). The distributions of OT were analyzed in five different sizes of pulmonary artery branches in each of 18 pulmonary segmental arteries (90 in total). The frequency of OT in each patient was evaluated by determining the percentage of examined sections containing OT. RESULTS: OT were confirmed in 59 of 64 (92%) patients. The mean frequency of OT per patient was 27% of the 90 branches. Among the segmental arteries, the right posterior basal lobe showed the highest frequency of OT; among the five artery branches examined, the subsegmental branch showed the highest frequency of OT. OT were not detected in arterioles. Patients with recent trauma or surgery and inpatients showed significantly lower frequencies of OT than those without these risk factors. The 26 patients with prolonged pre-existing symptoms lasting more than a day showed a higher frequency of OT than the 12 patients who suffered for less than a day and the 26 without pre-existing symptoms. CONCLUSIONS: Most patients with acute fatal PE have a subclinical history of recurrent PE. The frequency of their untreated PE is suspected to correlate with specific risk factors for venous thromboembolism and their clinical course.


Sujet(s)
Artère pulmonaire/anatomopathologie , Embolie pulmonaire/complications , Adulte , Sujet âgé , Autopsie , Femelle , Humains , Mâle , Adulte d'âge moyen , Embolie pulmonaire/anatomopathologie , Récidive , Facteurs de risque , Thrombose/anatomopathologie , Thrombose veineuse/anatomopathologie
3.
Acta Neurochir (Wien) ; 149(9): 897-902; discussion 902, 2007.
Article de Anglais | MEDLINE | ID: mdl-17690837

RÉSUMÉ

BACKGROUND: High rates of overall- and event-free survival have been reported in patients with intracranial germinoma treated by radiotherapy. We report the long-term results after treatment initially with chemotherapy, but without radiation. PATIENTS AND METHOD: Five patients with an intracranial germinoma were treated with 2 cycles of etoposide and cisplatin, without radiotherapy. All achieved complete remission; 3 suffered recurrence within 2 years and were again treated with 2 cycles of etoposide and cisplatin followed by radiotherapy. RESULTS: At long-term follow-up, each of the 5 patients was in complete remission without further recurrence. Each patient with a neurohypophyseal germinoma who presented with endocrinopathy had initially recovered endocrinological function. CONCLUSION: In a patient with a germinoma chemotherapy, and restriction of radiation to those with recurrence may allow restoration of hypophyseal function damaged by the intracranial germinoma without compromising long term survivial.


Sujet(s)
Antinéoplasiques d'origine végétale/usage thérapeutique , Antinéoplasiques/usage thérapeutique , Tumeurs du cerveau/traitement médicamenteux , Cisplatine/usage thérapeutique , Étoposide/usage thérapeutique , Germinome/traitement médicamenteux , Adolescent , Affections des ganglions de la base/traitement médicamenteux , Tumeurs du cerveau/diagnostic , Enfant , Maladies endocriniennes/étiologie , Maladies endocriniennes/physiopathologie , Femelle , Germinome/complications , Germinome/diagnostic , Humains , Études longitudinales , Imagerie par résonance magnétique , Mâle , Récidive tumorale locale/traitement médicamenteux , Glande pinéale , Neurohypophyse/physiopathologie , Tumeurs de l'hypophyse/complications , Tumeurs de l'hypophyse/traitement médicamenteux , Récupération fonctionnelle , Induction de rémission , Reprise du traitement
4.
J Med ; 35(1-6): 187-99, 2004.
Article de Anglais | MEDLINE | ID: mdl-18084877

RÉSUMÉ

Mitral valve prolapse (MVP) is closely related to myocardial sympathetic nerve function. This study evaluated the presence of impaired myocardial sympathetic nerve function by Iodine-123-metaiodobenzylguanidine (MIBG) scintigraphy in ten patients with MVP. For comparison, 15 healthy subjects without heart disease were investigated (control group). Single photon emission computed tomography (SPECT) and anterior planar myocardial scintigraphy were performed 15 min (initial images) and 3 hours (delayed images) after injection of MIBG (111 MBq). The location and degrees of reduced tracer uptake were evaluated. Myocardial MIBG uptake was quantified by uptake ratio of the heart (H) to upper mediastinum (M) on the anterior planar images (H/M). Percentage washout of MIBG in nine sectors of all oblique slices along the short-axis was calculated. The washout rates were higher at the inferoposterior and septal segments in patients with anterior leaflet prolapse, and at inferoposterior and lateral segments in patients with posterior leaflet prolapse. The bull's eye map showed increased washout rate in the apical and posteroseptal basal segments. There was no significant difference in the H/M ratio between MVP patients and the control group. These results indicate that MIBG can be used to evaluate localized myocardial sympathetic nerve function in MVP.


Sujet(s)
3-Iodobenzyl-guanidine , Coeur/imagerie diagnostique , Coeur/innervation , Prolapsus de la valve mitrale/imagerie diagnostique , Radiopharmaceutiques , Système nerveux sympathique/physiopathologie , 3-Iodobenzyl-guanidine/administration et posologie , Adulte , Sujet âgé , Femelle , Humains , Mâle , Adulte d'âge moyen , Prolapsus de la valve mitrale/physiopathologie , Radiopharmaceutiques/administration et posologie , Système nerveux sympathique/imagerie diagnostique , Tomographie par émission monophotonique
5.
Lasers Surg Med ; 29(1): 78-81, 2001.
Article de Anglais | MEDLINE | ID: mdl-11500867

RÉSUMÉ

BACKGROUND AND OBJECTIVE: Treatment of facial angiofibromata (AF) relied largely upon cutaneous resurfacing. While effective, resurfacing affects large areas with attendant risks of dyspigmentation, infection, and scarring. We investigated the pulsed KTP (532 nm) laser energy for its high absorption by melanin and hemoglobin as a photothermal destructive method for treating AF. STUDY DESIGN/MATERIALS AND METHODS: In five patients (Fitzpatrick phototypes II-;VI), AF were treated with the KTP laser (10 ms, 20 J/cm(2), 2 mm beam) using stacked pulses (2-3.3 Hz) or passes. No cooling device was employed. Each pulse evoked puffs of steam and caused progressive flattening of AF. Normal intervening skin was strictly avoided. Patients underwent one to five sessions in which as many as 100 lesions were treated. RESULTS: Individual lesions responded with complete flattening in one or two treatments. While this effect has persisted for 18-;24 months, slow recrudescence is expected. Transient hypopigmentation and hyperpigmentation were localized to treated skin. No scarring, infection, or other adverse events were observed. Patient satisfaction with this method was high due to rapid healing time ( < 10 days), minimal pain, ease of wound care, and efficacy. CONCLUSIONS: "Hot" KTP laser is an effective and safe method of treatment for facial AF. Limiting treatment only to lesional skin allowed rapid healing and very limited adverse effects despite the increased non-specific thermal damage caused by high fluence, long pulse duration, and an absence of superficial tissue cooling.


Sujet(s)
Angiofibrome/chirurgie , Tumeurs de la face/chirurgie , Thérapie laser/méthodes , Angiofibrome/complications , Enfant , Enfant d'âge préscolaire , Tumeurs de la face/complications , Humains , Complexe de la sclérose tubéreuse/complications , Cicatrisation de plaie
6.
Adv Dermatol ; 17: 301-23, 2001.
Article de Anglais | MEDLINE | ID: mdl-11758121

RÉSUMÉ

The ongoing effort to create an optimal method of skin rejuvenation has led to several new treatment options. Microdermabrasion and various nonablative laser resurfacing systems produce minimal skin injury, whereas current RF resurfacing devices may create both ablative or nonablative effects. The less invasive methods do limit the length of an uncomfortable healing time; however, studies appear to indicate that the results are less impressive than those produced by more destructive techniques and may prove only temporary over the time frame of a year. Efficacy and durability of clinical improvement seem to be inversely related to the wounding depth, the length of the healing period, or both. The search continues for the perfect method of skin rejuvenation, which minimizes cost, healing time, adverse effects, and discomfort and maximizes efficacy, response durability, and reproducibility. With advancements in technology, rejuvenation methods slowly approach these elusive goals.


Sujet(s)
Dermabrasion/méthodes , Thérapie laser/méthodes , Rhytidoplastie/méthodes , Électrochirurgie/effets indésirables , Électrochirurgie/méthodes , Humains , Thérapie laser/effets indésirables , , Vieillissement de la peau , Cicatrisation de plaie
7.
Bone ; 27(5): 655-9, 2000 Nov.
Article de Anglais | MEDLINE | ID: mdl-11062352

RÉSUMÉ

We recently found that silver impregnation staining with protargol (silver protein), that is, a modified Bodian method, is useful for histologically identifying the details of bone canaliculi structure, using thin sections of decalcified bone tissues. With this staining method, we conducted the present study to assess the development of bone canaliculi during the process of intramembranous ossification using a fracture-like stimulation model of the rat femur. After making a drill-hole in the cortex of the rat femur, decalcified thin sections were obtained after 3, 5, 7, and 14 days by the standard paraffin-embedding procedure. Silver staining for bone canaliculi was performed using our previously reported technique. The results showed that woven bone covered the fracture surface of the cortex after 5 days, then immature lamellar bone attached to the woven bone after 7 days, and finally the lamellar bone matured and became thick with appositional growth after 14 days. The osteocytes in the woven bone appeared at an early stage of bone repair and developed a few canaliculi that were short and irregularly distributed in the osteoid matrix, while the osteocytes in the lamellar bone at a late stage formed many bone canaliculi that were long and regularly distributed in mature bone matrix. Therefore, we concluded that woven bone osteocytes may be necessary for induction of the lamellar bone osteocytes followed by active appositional growth of the lamellar bone at the early stage of bone repair, and also that both bone tissues could be clearly distinguished from one another based on the pattern of development of bone canaliculi by the osteocytes, as seen with the use of our sensitive staining method.


Sujet(s)
Os et tissu osseux/anatomie et histologie , Consolidation de fracture , Animaux , Rats , Rat Wistar
8.
Dermatol Surg ; 25(10): 819-22, 1999 Oct.
Article de Anglais | MEDLINE | ID: mdl-10594587

RÉSUMÉ

BACKGROUND: Eruptive vellus hair cysts (EVHC) frequently resist a variety of treatment modalities. While pulsed carbon dioxide (CO2) laser has been used effectively for facial EVHC, this laser presents significant risks for hypertrophic scarring when used on truncal sites. Due to absorption of 2940 nm energy by both tissue water and protein, the erbium:yttrium-aluminum-garnet (Er:YAG) laser ablates more cleanly and creates less residual thermal injury in the wound bed. This laser might prove efficacious and safe in treating nonfacial EVHC. OBJECTIVE: To assess treatment efficacy and wound healing after Er:YAG laser ablation of EVHC. METHODS: Two patients with 32 truncal EVHC were treated with pulsed Er:YAG laser using a drilling technique followed by second intention healing. RESULTS: Laser treatment sites healed without permanent dyspigmentation or hypertrophic scarring. No lesion recurrence was observed. CONCLUSION: Er:YAG laser ablation is an effective method for treating EVHC at anatomic sites prone to hypertrophic scar formation.


Sujet(s)
Kyste épidermique/chirurgie , Maladies du système pileux/chirurgie , Abdomen , Adulte , Kyste épidermique/anatomopathologie , Femelle , Maladies du système pileux/anatomopathologie , Humains , Mâle , Thorax
9.
Biosci Biotechnol Biochem ; 63(6): 973-7, 1999 Jun.
Article de Anglais | MEDLINE | ID: mdl-10427682

RÉSUMÉ

(+)-Catechin and (-)-epicatechin are known to be biologically effective antioxidants present in the human diet, particularly in wine and tea. We studied the metabolism of these compounds to elucidate the truly active structures in biological fluids by their oral administration to rats. Without any treatment with beta-glucuronidase and sulfatase, a pair of metabolites were detected at much higher concentrations in the plasma, bile, and urine than the originally ingested compounds. Each major metabolite found in the plasma at the highest concentration was excreted in both the bile and urine, and was purified from urine. Their chemical structures were established to be (+)-catechin 5-O-beta-glucuronide and (-)-epicatechin 5-O-beta-glucuronide by MS and NMR analyses. These glucuronide conjugates exhibited high antioxidative activities as superoxide anion radical scavengers like their parent compounds. It is concluded that (+)-catechin 5-O-beta-glucuronide and (-)-epicatechin 5-O-beta-glucuronide are the biologically active in vivo structures of the ingested polyphenolic antioxidants.


Sujet(s)
Antioxydants/métabolisme , Catéchine/métabolisme , Animaux , Antioxydants/composition chimique , Bile/composition chimique , Catéchine/sang , Catéchine/composition chimique , Flavonoïdes/composition chimique , Piégeurs de radicaux libres/composition chimique , Spectroscopie par résonance magnétique , Mâle , Rats , Rat Wistar , Stéréoisomérie , Superoxydes/composition chimique
10.
11.
J Biochem ; 125(4): 838-45, 1999 Apr.
Article de Anglais | MEDLINE | ID: mdl-10101300

RÉSUMÉ

Some alpha(1,3)fucosylated oligosaccharides serve as counter receptors to lectin-like adhesion proteins or are expressed with temporal precision during embryogenesis, and alpha(1, 3)fucosyltransferase is a key enzyme in the production of these oligosaccharides. Two alpha(1,3)-fucosyltransferase genes, designated zFT1 and zFT2, were cloned from zebrafish. Sequence comparisons with other genes indicated that zFT1 and zFT2 share about 30% amino acid sequence identity with human alpha(1, 3)fucosyltransferases. Although the alpha(1,3)fucosyltransferases cloned so far can be classified into three types-myeloid, Lewis, and leukocyte-by virtue of their amino acid sequences, phylogenetic analysis indicated that neither zFT1 nor zFT2 belongs to any of these categories. The expression of zFT1 or zFT2 in mammalian cells induces alpha(1,3)fucosyltransferase activity to synthesize the Lewis x structure from pyridylaminated lacto-N-neotetraose; however, lacto-N-tetraose does not serve as a substrate. Reverse transcriptase-polymerase chain reaction analysis revealed that zFT1 is transcribed during a restricted period before hatching, whereas the mRNA for zFT2 was detected only after hatching.


Sujet(s)
Fucosyltransferases/génétique , Danio zébré/génétique , Séquence d'acides aminés , Animaux , Séquence nucléotidique , Cartographie chromosomique , Clonage moléculaire , ADN/génétique , Amorces ADN/génétique , Fucosyltransferases/métabolisme , Régulation de l'expression des gènes au cours du développement , Régulation de l'expression des gènes codant pour des enzymes , Humains , Antigènes CD15/biosynthèse , Données de séquences moléculaires , Phylogenèse , ARN messager/génétique , ARN messager/métabolisme , RT-PCR , Similitude de séquences d'acides aminés , Spécificité d'espèce , Danio zébré/embryologie , Danio zébré/métabolisme
12.
Eur Respir J ; 12(4): 831-6, 1998 Oct.
Article de Anglais | MEDLINE | ID: mdl-9817154

RÉSUMÉ

Inducible nitric oxide (NO) synthase (iNOS)-mediated hyperproduction of NO in airways has been reported in asthmatic patients. However, the role of NO in the pathogenesis of asthma has not yet been fully elucidated. The aim of this study was to examine whether the iNOS-derived NO affects airway microvascular leakage, one of the characteristic features of asthmatic airway inflammation. Guinea-pigs were exposed to lipopolysaccharide (LPS) (1 mg x mL(-1)) by inhalation in order to induce iNOS in the airways, and the histochemical staining of reduced nicotinamide-adenine dinucleotide phosphate (NADPH)-diaphorase activity was determined 5 h after the inhalation to confirm the iNOS induction. Airway microvascular leakage to subthreshold doses of substance P (0.3 microg x kg(-1), i.v.) was also examined in the absence and presence of an iNOS inhibitor (aminoguanidine) in LPS- or saline-exposed (control) animals using Evans blue dye and Monastral blue dye. In the LPS-exposed animals, increased NADPH-diaphorase activity was observed in the airway microvasculature compared with the control animals. Substance P caused significant airway microvascular leakage assessed by Evans blue dye in all airway levels in the LPS-exposed animals but not in the control group. This was also confirmed by Monastral blue dye extravasation. Aminoguanidine abolished this LPS-induced enhancement of plasma leakage to substance P without changing the systemic blood pressure. These results may suggest that inducible nitric oxide synthase-derived nitric oxide is capable of potentiating neurogenic plasma leakage in airways.


Sujet(s)
Syndrome de fuite capillaire/enzymologie , Nitric oxide synthase/métabolisme , Administration par inhalation , Analyse de variance , Animaux , Hyperréactivité bronchique/enzymologie , Hyperréactivité bronchique/anatomopathologie , Tests de provocation bronchique , Syndrome de fuite capillaire/induit chimiquement , Syndrome de fuite capillaire/anatomopathologie , Perméabilité capillaire/effets des médicaments et des substances chimiques , Modèles animaux de maladie humaine , Bleu d'Evans/pharmacologie , Cochons d'Inde , Lipopolysaccharides/administration et posologie , Mâle , Nitric oxide synthase/effets des médicaments et des substances chimiques , Probabilité , Valeurs de référence , Substance P/pharmacocinétique
14.
Eur Respir J ; 12(1): 71-4, 1998 Jul.
Article de Anglais | MEDLINE | ID: mdl-9701417

RÉSUMÉ

It has recently been shown that immunoglobulin (Ig)E facilitates the cholinergic bronchoconstrictor pathway in human tissue in vitro. However, whether this occurs in humans in vivo has not been clarified. In this study, the bronchodilator responses were examined to inhalation of a submaximal dose of the anticholinergic agent oxitropium bromide (600 microg) in normal and allergic subjects with various levels of total serum IgE. Values of the forced expiratory volume in one second (FEV1) for all subjects were greater than 80% of predicted, but were negatively correlated with serum IgE levels (p<0.01). Oxitropium bromide inhalation induced an increase in FEV1 that was significantly greater in allergic rhinitis patients with high serum IgE (155+/-20 mL (mean+/-SEM), p<0.05) than in healthy subjects (64+/-21 mL) or those with allergic rhinitis but low serum IgE (82+/-21 mL, p<0.05). In contrast, the effects of the inhaled beta2-adrenergic agent orciprenaline sulphate (2.25 mg) were not significantly different among the three groups. In conclusion, higher serum immunoglobulin E levels were correlated with lower values of the forced expiratory volume in one second, and anticholinergic agents, but not beta2-adrenergic agents, caused more pronounced bronchodilation in subjects with high than in those with low immunoglobulin E levels. These data suggest that serum immunoglobulin E may be one of the factors that determine the airway tone, possibly via cholinergic mechanisms.


Sujet(s)
Résistance des voies aériennes/immunologie , Asthme/immunologie , Neurofibres cholinergiques/physiologie , Immunoglobuline E/sang , Parasympatholytiques/administration et posologie , Rhinite spasmodique apériodique/immunologie , Rhinite allergique saisonnière/immunologie , Dérivés de la scopolamine/administration et posologie , Administration par inhalation , Adulte , Résistance des voies aériennes/effets des médicaments et des substances chimiques , Asthme/traitement médicamenteux , Neurofibres cholinergiques/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Femelle , Volume expiratoire maximal par seconde/effets des médicaments et des substances chimiques , Humains , Mâle , Rhinite spasmodique apériodique/traitement médicamenteux , Rhinite allergique saisonnière/traitement médicamenteux , Méthode en simple aveugle
15.
Endocr J ; 45(5): 631-6, 1998 Oct.
Article de Anglais | MEDLINE | ID: mdl-10395243

RÉSUMÉ

There has been accumulating evidence that pituitary adenomas which cause Cushing's disease are located not only in sella turcica but also in various extrasellar and intracranial regions. We describe a case of Cushing's disease caused by a supra- and extrasellar ACTH-producing microadenoma, which originated in the anterior pituitary and extended upward without connecting to the stalk. The pituitary microadenoma was identified and removed by transsphenoidal microsurgery. After the surgery the patient experienced complete remission. This type of pituitary microadenoma is considered to be rare, but in order to accomplish successful surgical treatment, it is necessary to consider that pituitary adenomas which cause Cushing's disease may be located in such an unusual position.


Sujet(s)
Adénomes/complications , Syndrome de Cushing/étiologie , Tumeurs de l'hypophyse/complications , Adénomes/diagnostic , Adénomes/chirurgie , Hormone corticotrope/analyse , Adulte , Syndrome de Cushing/sang , Femelle , Humains , Immunohistochimie , Imagerie par résonance magnétique , Microchirurgie/méthodes , Invasion tumorale , Adénohypophyse , Tumeurs de l'hypophyse/diagnostic , Tumeurs de l'hypophyse/chirurgie , Réintervention
17.
Anticancer Drugs ; 8(7): 666-70, 1997 Aug.
Article de Anglais | MEDLINE | ID: mdl-9311442

RÉSUMÉ

ACR-CH, which consists of aclarubicin (ACR) adsorbed onto activated carbon particles, was developed for locoregional chemotherapy for breast cancer. Thirty patients with breast cancer received an ACR (10 mg) injection intra- and peri-tumorally, either as ACR-CH or as ACR aqueous solution (ACR-AQ) 5 min before the operation for breast cancer. The ACR concentrations were significantly higher in the peritumoral regions and regional lymph nodes, and were also significantly lower in the blood plasma in patients given ACR-CH versus patients given ACR-AQ.


Sujet(s)
Aclarubicine/administration et posologie , Aclarubicine/pharmacocinétique , Antibiotiques antinéoplasiques/administration et posologie , Antibiotiques antinéoplasiques/pharmacocinétique , Tumeurs du sein/chirurgie , Charbon de bois , Adsorption , Tumeurs du sein/traitement médicamenteux , Tumeurs du sein/anatomopathologie , Vecteurs de médicaments , Femelle , Humains , Noeuds lymphatiques/métabolisme , Métastase lymphatique , Adulte d'âge moyen
18.
Am J Respir Crit Care Med ; 156(1): 217-22, 1997 Jul.
Article de Anglais | MEDLINE | ID: mdl-9230751

RÉSUMÉ

Nitric oxide (NO), a neurotransmitter of inhibitory nonadrenergic noncholinergic (iNANC) nerves in airways, is a radical with a short half-life, and its function may be modified by airway inflammation. To test this hypothesis, we examined whether airway allergic inflammation affects iNANC responses mediated by NO in guinea pigs in vitro. Animals sensitized with ovalbumin (OA) were challenged with 0.03% OA (OA group) or saline (saline group) by inhalation on 3 consecutive days. On the day after the final challenge, iNANC responses elicited by electrical field stimulation (2 to 16 Hz) or relaxation responses to 3-morpholinosydnonimine (SIN-1), 10(-8) to 10(-4) M, were obtained in the tracheal strips precontracted by histamine (3 x 10(-6) M) in the presence of atropine and propranolol (both 10(-6) M). The INANC responses of the OA group were significantly attenuated compared with those of the saline group (p < 0.05), and the inhibitory effect of a NO synthase (NOS) inhibitor, Nm-nitro-L-arginine methyl ester, on the INANC responses was abolished in the OA group. SIN-1-induced tracheal smooth muscle relaxation was also significantly affected by antigen exposure (p < 0.05), the effect of which disappeared in the presence of a NO scavenger, carboxy PTIO (3 x 10(-6) M). The impairment of the INANC responses after antigen exposure was significantly restored by superoxide dismutase (1,000 U/ml), especially at lower frequencies. Histochemical demonstration of NADPH-diaphorase-positive nerves representing neural NOS density was not different between the two groups. These results suggest that allergic airway inflammation impairs neural NO-induced relaxation, presumably by inhibiting the access of neural NO to the airway smooth muscle.


Sujet(s)
Bronches/innervation , Relâchement musculaire/physiologie , Muscles lisses/physiologie , Nitric oxide synthase/antagonistes et inhibiteurs , Monoxyde d'azote/physiologie , Animaux , Bronches/composition chimique , Cochons d'Inde , Techniques in vitro , Inflammation/induit chimiquement , Inflammation/physiopathologie , Mâle , Relâchement musculaire/effets des médicaments et des substances chimiques , Muscles lisses/effets des médicaments et des substances chimiques , NADPH dehydrogenase/analyse , Ovalbumine
19.
Eur Respir J ; 10(1): 13-9, 1997 Jan.
Article de Anglais | MEDLINE | ID: mdl-9032485

RÉSUMÉ

This study examines the role of endogenous nitric oxide (NO) in airway microvascular leakage induced inflammatory mediators, which play an important role in asthmatic airways. Guinea-pigs were anesthetized and mechanically-ventilated with monitoring of arterial blood pressure, and airway microvascular leakage induced by intravenous injection of substance P (SP), leukotriene D4 (LTD4) and histamine was evaluated using Evans blue dye and Monastral blue dye in the presence and absence of the NO synthase inhibitors, L-NG-nitroarginine methyl ester (L-NAME) and L-NG-monomethyl arginine (L-NMMA). The effect of a soluble guanylate cyclase inhibitor, LY83583, on SP-induced dye leakage was also examined. Intravenous injection of SP (1 microgram.kg-1), LTD4 (1 microgram.kg-1) and histamine (100 micrograms.kg-1) significantly increased dye extravasation at all airway levels. Pretreatment with L-NAME (10 mg.kg-1 i.v.) and L-NMMA (100 mg.kg-1 i.v.) significantly inhibited SP-induced extravasation, and L-arginine (100 mg.kg-1 i.v.) reversed L-NAME-induced inhibition. L-NAME (10 mg.kg-1 i.v.) also significantly inhibited LTD4-induced dye extravasation only in central airways, and this inhibitory effect was abolished by a neurokinin-1 (NK1) antagonist, FK888 (10 mg.kg-1 i.v.) pretreatment. Histamine-induced dye extravasation was not affected by L-NAME. LY83583 (2.5 and 7.5 mg.kg-1 i.v.) partially but significantly reduced SP-induced dye leakage. These results suggest that endogenous nitric oxide plays a role in neurokinin-1 receptor-mediated airway microvascular leakage, and presumably involves the guanylate cyclase pathway.


Sujet(s)
Perméabilité capillaire/effets des médicaments et des substances chimiques , Médiateurs de l'inflammation/pharmacologie , Poumon/vascularisation , Monoxyde d'azote/physiologie , Aminoquinoléines/pharmacologie , Animaux , Arginine/pharmacologie , Asthme/physiopathologie , Agents colorants , Dipeptides/pharmacologie , Antienzymes/pharmacologie , Bleu d'Evans , Extravasation de produits diagnostiques ou thérapeutiques/diagnostic , Extravasation de produits diagnostiques ou thérapeutiques/étiologie , Guanylate cyclase/antagonistes et inhibiteurs , Cochons d'Inde , Histamine/administration et posologie , Histamine/pharmacologie , Indoles/pharmacologie , Injections veineuses , Leucotriène D4/administration et posologie , Leucotriène D4/pharmacologie , Mâle , Microcirculation/effets des médicaments et des substances chimiques , L-NAME/pharmacologie , Antagonistes du récepteur de la neurokinine-1 , Nitric oxide synthase/antagonistes et inhibiteurs , Composés organométalliques , Substance P/administration et posologie , Substance P/pharmacologie , oméga-N-Méthylarginine/pharmacologie
20.
Am J Respir Crit Care Med ; 154(5): 1272-6, 1996 Nov.
Article de Anglais | MEDLINE | ID: mdl-8912735

RÉSUMÉ

Airway cholinergic hyperresponsiveness is frequently observed in asthmatic patients. Recent reports suggest the possible involvement of IgE in hyperresponsiveness, although the exact mechanism is still uncertain. In this study, we examined whether incubation with IgE could facilitate the cholinergic function in human airways. Bronchi were obtained from 20 patients undergoing lung resection. Cholinergic contractile responses were induced by electrical field stimulation (EFS) or exogenous acetylcholine (ACh), and they were assessed by isometric tension measurement. EFS-induced ACh release from cholinergic nerves was also measured by high performance liquid chromatography. Incubation with IgE significantly enhanced EFS-induced bronchial contraction and ACh release as compared with the values of the bronchi incubated with heat inactivated IgE (control) (p < 0.05, respectively), but it did not alter the contractile responses induced by exogenous ACh. Pretreatment with the muscarinic M2-receptor agonist pilocarpine reduced the EFS-induced ACh release in the control tissues (p < 0.05), but not in the tissues incubated with IgE. The M2-receptor antagonist methoctramine significantly enhanced the EFS-induced contraction in control bronchi (p < 0.05), but this augmentation was not observed in the tissues incubated with IgE. These results suggest that IgE itself can enhance cholinergic bronchial contraction via facilitation of ACh release from cholinergic nerves and that this augmentation is related to autoreceptor M2 dysfunction at nerve endings.


Sujet(s)
Acétylcholine/métabolisme , Bronches/effets des médicaments et des substances chimiques , Immunoglobuline E/pharmacologie , Pilocarpine/pharmacologie , Transmission synaptique/effets des médicaments et des substances chimiques , Acétylcholine/pharmacologie , Sujet âgé , Bronches/métabolisme , Bronchoconstriction/effets des médicaments et des substances chimiques , Stimulation électrique , Humains , Techniques in vitro , Adulte d'âge moyen , Parasympathomimétiques/pharmacologie
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