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1.
Gene Ther ; 18(11): 1063-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21562589

RESUMO

Hepatocyte growth factor (HGF) promotes regeneration of the central nervous system, but its effects on the peripheral nervous system remain unclear. This study was conducted to elucidate the effect of HGF on regeneration of the murine facial nerve after crush injury. To do so, a replication-defective herpes simplex virus vector that incorporated HGF was prepared (HSV-HGF). The main trunk of the facial nerve was compressed by mosquito hemostats, and HSV-HGF, control vector or medium was then applied to the compressed nerve. We found that mice in the HGF group required significantly fewer days for complete recovery from nerve compression. Furthermore, the amplitude of the evoked buccinator muscle compound action potential increased following HSV-HGF application. HGF expression in and around the compressed nerve was demonstrated by enzyme-linked immunoassay and immunohistochemistry. In addition, HSV-HGF introduction around the damaged nerve significantly accelerated recovery of function of the facial nerve. These data suggest a possible role of HGF in promoting facial nerve regeneration after nerve damage. Furthermore, this viral delivery method may be applied clinically for many types of severe facial palsy during facial nerve decompression surgery.


Assuntos
Traumatismos do Nervo Facial/terapia , Terapia Genética/métodos , Fator de Crescimento de Hepatócito/genética , Regeneração Nervosa/efeitos dos fármacos , Simplexvirus/genética , Animais , Nervo Facial/fisiologia , Vetores Genéticos , Camundongos , Síndromes de Compressão Nervosa/terapia , Regeneração Nervosa/genética
2.
Philos Trans R Soc Lond B Biol Sci ; 355(1396): 441-7, 2000 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-10836497

RESUMO

Recent progress in single-molecule detection techniques is remarkable. These techniques have allowed the accurate determination of myosin-head-induced displacements and how mechanical cycles are coupled to ATP hydrolysis, by measuring individual mechanical events and chemical events of actomyosin directly at the single-molecule level. Here we review our recent work in which we have made detailed measurements of myosin step size and mechanochemical coupling, and propose a model of the myosin motor.


Assuntos
Proteínas Motores Moleculares/fisiologia , Contração Muscular/fisiologia , Miosinas/fisiologia , Actinas/química , Actinas/fisiologia , Actomiosina/química , Actomiosina/fisiologia , Animais , Fenômenos Biomecânicos , Modelos Biológicos , Proteínas Motores Moleculares/química , Miosinas/química , Miosinas/metabolismo
3.
Curr Opin Cell Biol ; 12(1): 20-5, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10679365

RESUMO

Progress in imaging techniques and nano-manipulation of single molecules has been remarkable. These techniques have allowed the accurate determination of myosin-head-induced displacements and of how the mechanical cycles of the actomyosin motor are coupled to ATP hydrolysis. This has been achieved by measuring mechanical and chemical events of actomyosin directly at the single molecule level. Recent studies have made detailed measurements of myosin step size and mechanochemical coupling. The results of these studies suggest a new model for the mechanism of motion underlying actomyosin motors, which differs from the currently accepted lever-arm swinging model.


Assuntos
Actomiosina/química , Actomiosina/metabolismo , Proteínas Motores Moleculares/química , Proteínas Motores Moleculares/metabolismo , Animais , Modelos Químicos , Miosinas/química , Miosinas/metabolismo , Conformação Proteica
4.
Surg Endosc ; 13(8): 773-7, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10430682

RESUMO

BACKGROUND: Thanks to various technical innovations and advances in instrumentation, laparoscopic surgical intervention is now possible for certain congenital anomalies in children. To test the applicability of laparoscopic surgery in neonates, we reviewed our personal experience of neonatal laparoscopic surgery, focusing on cardiopulmonary function, surgical procedures, problems with devices, and degree of associated surgical stress. METHODS: We performed 65 laparoscopic procedures in neonates. Their ages ranged from 2 to 30 days old, and their body weights ranged from 1,980 to 4,780 g. All 65 laparoscopic procedures were carried out without mortality or serious morbidity. RESULTS: As complications, we encountered four cases of hypothermia due to rapid insufflation of carbon dioxide (CO(2)). We also found that relative hypercapnea (increase in end-tidal CO(2) as high as 61 mmHg) developed unless hyperventilation and a relatively high peak insufflation pressure were maintained during pneumoperitoneum. No cardiac depression developed at this insufflation pressure. Fluid and electrolyte balance during our cases of newborn laparoscopic surgery, as well as the doses and volumes of fluid and electrolytes administered, were identical to those required for open surgery. Interleukin-6 (IL-6) was measured serially to estimate the degree of associated surgical stress and was found to be significantly lower in neonates who had received laparoscopic procedures than in those who had received open procedures. CONCLUSION: Laparoscopic surgery can be carried out safely even in neonates.


Assuntos
Laparoscopia , Testes de Função Cardíaca , Humanos , Recém-Nascido , Interleucina-6/metabolismo , Complicações Intraoperatórias , Laparoscópios , Laparoscopia/efeitos adversos , Complicações Pós-Operatórias , Testes de Função Respiratória , Estresse Fisiológico/imunologia , Equilíbrio Hidroeletrolítico
5.
J Pediatr Surg ; 34(2): 370-2, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10052826

RESUMO

BACKGROUND/PURPOSE: The aim of this study was to evaluate the advantages or disadvantages of laparoscopic pyloromyotomy compared with open transumbilical fold pyloromyotomy. METHODS: Thirty consecutive laparoscopic extramucosal pyloromyotomies (LP) performed from 1994 to 1997 were compared with 30 consecutive open pyloromyotomies (OP) performed during the same period with regard to age at operation, body weight, thickness of hypertrophied pyloric muscle, operating time, time of return to full feeding, frequency of postoperative emesis, surgical complications, and degree of surgical stress reflected by interleukin-6 (IL-6). LP was performed according to conventional techniques, and OP was performed using a transumbilical fold approach. RESULTS: The groups were matched for age at operation, preoperative clinical and physical status, laboratory data, and size of the hypertrophied pylorus assessed by ultrasonography. There was a learning curve with LP; the average operating time required for the first 10 cases was significantly longer than the time required for OP, but later cases took just as long as OP cases. Time taken to full feeding was significantly shorter in the LP group than the OP group (LP, 38 hours v OP, 64 hours). One case was converted from LP to OP because of mucosal perforation. The incidence of postoperative emesis was significantly higher in the OP group than in the LP group (OP, 25% v LP, 3%). The mean length of hospitalization was significantly shorter in LP (P < .01). The intraoperative peak values of IL-6 in LP were significantly lower than those in the OP group (P < .01). CONCLUSIONS: The advantages of LP are improved cosmesis, decreased surgical stress with earlier postoperative recovery, and shorter hospitalization. Because LP uses reusable devices, and the mean period of hospitalization is shorter, average operating costs could be reduced, representing a net saving in total hospital charges.


Assuntos
Laparoscopia/métodos , Estenose Pilórica/cirurgia , Ingestão de Alimentos , Humanos , Hipertrofia/cirurgia , Lactente , Recém-Nascido , Laparoscópios , Complicações Pós-Operatórias , Fatores de Tempo , Resultado do Tratamento
6.
Immunobiology ; 195(2): 160-71, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8877393

RESUMO

Immunosuppression by anti-adhesion molecule antibody of free or vascularized skin allograft rejection was investigated in rats. Lewis (LEW, RT11) rats were used as donors and Fisher (F344, RT11v1) rats as the recipients. When F344 rats were treated intraperitoneally (i.p.) with anti-intercellular adhesion molecule-1 (ICAM-1) mAb (1A29) (3 mg/kg/day) and anti-leukocyte function-associated antigen-1 (LFA-1) mAb (WT.1) (3 mg/kg/day) one day prior to grafting and daily after grafting for nine days, free skin graft survival was prolonged only slightly compared with that in control rats which were injected i.p. with a daily dose of 6 mg/kg of anti-TNP mAbs (H1-6-2) one day prior to grafting and daily after grafting for nine days. (Mean survival time [MST] of the free skin graft was 11.2 +/- 0.6 days in the control group and 13.4 +/- 0.3 days in the 1A29 + WT-1 treated group [p < 0.01], respectively.) On the other hand, the vascularized graft survival was prolonged significantly in anti-ICAM-1/LFA-1 mAbs-treated F344 rats as compared with that in control rats. (The mean vascularized graft survival time was 14.2 +/- 0.7 days in the control group and 21.5 +/- 1.9 days in 1A29 + WT-1 treated group [p < 0.002]). Our results suggest that interaction with ICAM-1 and LFA-1 is more important in the rejection of vascularized skin allografts than that of free skin allografts.


Assuntos
Anticorpos Monoclonais/farmacologia , Rejeição de Enxerto/prevenção & controle , Imunossupressores/farmacologia , Molécula 1 de Adesão Intercelular/imunologia , Antígeno-1 Associado à Função Linfocitária/imunologia , Transplante de Pele/imunologia , Animais , Endotélio Vascular/imunologia , Sobrevivência de Enxerto/imunologia , Masculino , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Transplante Homólogo
7.
Biosci Biotechnol Biochem ; 59(11): 2018-21, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8541639

RESUMO

Nonenzymatic glycation of bovine serum albumin (BSA) was inhibited in vitro by some extracts of 34 kinds of spices. The methanol extract of thyme (Thymus vulgaris) had the most potent inhibitory activity among them. Chromatographic purification yielded four flavonoids, quercetin (1), eriodictyol (2), 5,6,4'-trihydroxy-7,8,3'-trimethoxyflavone (3), and cirsilineol (4). These known flavonoids suppressed the levels of advanced glycation end products (AGEs) and fructosamines, shown by the measurement of specific fluorescent groups and the reduction of nitroblue tetrazolium (NBT), respectively. The inhibitory activities were compared with those of other structure-related flavonoids and aminoguanidine.


Assuntos
Flavonoides/farmacologia , Glucose/metabolismo , Magnoliopsida/metabolismo , Soroalbumina Bovina/metabolismo , Flavonoides/química , Flavonoides/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Relação Estrutura-Atividade
8.
Carcinogenesis ; 15(11): 2669-72, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7955124

RESUMO

The anticlastogenic effect of 12 structurally different flavonoids was investigated in whole body gamma-ray irradiated mice. Each flavonoid was administered to ICR male mice by a single gastric intubation (5 mumol/kg) 6 h before gamma-ray irradiation (1.5 Gy) and the frequency of micronucleated reticulocytes (MNRETs) in peripheral blood was determined. In order to elucidate the mechanism of the anticlastogenic effect of these flavonoids, their antioxidative activities were examined by the thiobarbituric acid method using methyl linoleate and Fenton's reagent (Fe2+/H2O2). Of the 12 flavonoids, luteolin had the most marked effect on reducing the frequencies of MNRETs and also inhibiting lipid peroxidation. However, quercetin tetramethylether, which has methoxy groups instead of hydroxyl groups at the 3,7,3',4'-positions, and phloretin with an open C-ring showed the least anticlastogenic and antioxidative activity. A good correlation (r = 0.717, P < 0.01) was observed between the anticlastogenic activity and the antioxidative activity of the 12 flavonoids. These results suggest that the radioprotective effect of flavonoids in mice may be attributed to the hydroxyl radical scavenging potency in a direct or an endogenous enzyme mediated manner.


Assuntos
Antimutagênicos/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Protetores contra Radiação/farmacologia , Animais , Raios gama , Masculino , Camundongos , Camundongos Endogâmicos ICR , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos
9.
Biosci Biotechnol Biochem ; 58(8): 1479-85, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7765281

RESUMO

The 7-O-[2-O-(alpha-L-Rhamnopyranosyl)-beta-L-quinovoside] of naringenin and of hesperetin, and their dihydrochalcone (DHC) derivatives were synthesized by the method of Koenigs-Knorr (Ag2CO3 and quinoline). The reaction of TMS ethers of naringenin and of hesperetin with each of the alpha-acetofluoro derivatives of D-glucose, L-rhamnose, 2-O-(alpha-L-rhamnopyranosyl)-L-rhamnose, and 2-O-(alpha-L-rhamnopyranosyl)-D-glucose (neohesperidose), using boron trifluoride etherate as an activator, yielded coupling products which, after deprotection, gave naringenin 4'-O-beta-D-glucoside, naringenin 4'-O-alpha-L-rhamnoside, naringenin 4'-O-[2-O-(alpha-L-rhamnopyranosyl)-alpha-L-rhamnoside], hesperetin 3'-O-[2-O-(alpha-L-rhamnopyranosyl)-alpha-L-rhamnoside], and naringenin 4'-O-beta-neohesperidoside, respectively. Catalytic hydrogenation of these flavanones gave the corresponding DHC derivatives. Hesperetin DHC 4'-O-[2-O-(alpha-L-rhamnopyranosyl-beta-L-quinovoside] was 300 times sweeter than sucrose, while the other compounds were bitter or tasteless.


Assuntos
Chalcona/análogos & derivados , Flavonoides/síntese química , Glicosídeos/síntese química , Edulcorantes/síntese química , Sequência de Carboidratos , Chalcona/síntese química , Chalcona/química , Chalconas , Flavonoides/química , Glicosídeos/química , Dados de Sequência Molecular , Edulcorantes/química , Paladar
10.
Plast Reconstr Surg ; 93(5): 1012-20, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8134458

RESUMO

The distally based superficial sural artery flap, first described as a distally based neuroskin flap by Masquelet et al., is a skin island flap supplied by the vascular axis of the sural nerve. The aim of this paper is to refine the surgical technique in order to establish the reliability of this flap. We treated 20 patients with 21 distally based superficial sural artery flaps, including 2 fascial flaps. All flaps survived. Most flaps showed slight venous congestion. In the largest flap (10 cm wide by 13 cm long), edema lasted 2 months. In the flap whose pedicle was raised without the deep fascia, there was necrosis at the distal tip of the flap. The advantages are the following: The blood supply is reliable, elevation is easy and quick, and major arteries are not sacrificed. This new flap may be useful in selected circumstances.


Assuntos
Traumatismos da Perna/cirurgia , Perna (Membro)/irrigação sanguínea , Retalhos Cirúrgicos/métodos , Acidentes de Trânsito , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Pele/irrigação sanguínea , Traumatismos da Medula Espinal/complicações , Nervo Sural
11.
Biosci Biotechnol Biochem ; 57(12): 2099-103, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7764366

RESUMO

In order to clarify the substrate specificity of the alpha-L-mannosidase activity of naringinase (Sigma), the following disaccharides and phenol glycosides were freshly prepared: methyl 2-O-(alpha-L-mannopyranosyl)-beta-D-glucoside (1), methyl 3-O-(alpha-L-mannopyranosyl)-alpha-D-glucoside (2), methyl 4-O-(alpha-L-mannopyranosyl)-alpha-D-glucoside (3), methyl 5-O-(alpha-L-mannopyranosyl)-beta-D-glucoside (4), methyl 6-O-(alpha-L-mannopyranosyl)-alpha-D-glucoside (5), 6-O-(alpha-L-mannopyranosyl)-D-galactose (6), p-nitrophenyl alpha-L-mannoside (7), and 4-methyl umbelliferone alpha-L-mannoside (8). These compounds, except for 3 and 5 were hydrolyzed with naringinase.


Assuntos
Dissacarídeos/síntese química , Glicosídeo Hidrolases/metabolismo , Glicosídeos/síntese química , Manosídeos/síntese química , Complexos Multienzimáticos/metabolismo , beta-Glucosidase/metabolismo , Sequência de Carboidratos , Dissacarídeos/química , Dissacarídeos/metabolismo , Glicosídeos/química , Glicosídeos/metabolismo , Manosídeos/química , Manosídeos/metabolismo , Dados de Sequência Molecular , Fenóis/metabolismo , Especificidade por Substrato
14.
Biosci Biotechnol Biochem ; 57(1): 107-14, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27316881

RESUMO

To clarify the relationship between the structure and inhibitory action toward ß-D-galactosidase (EC 3.2.1.21) of isoflavones and isoflavone glycosides, a number of polyhydroxyisoflavones, and the α-L-rhamnosides and ß-L-quinovosides of daidzein and genistein were synthesized. Among the polyhydroxyisoflavones, 2',3',4',7-tetrahydroxyisoflavone showed the strongest inhibitory activity (Ki = 26 × 10(-6) M). Among the glycosides, all the L-rhamnosides were strong inhibitors, of which genistein 4',7-di-O-α-L-rhamnoside was the strongest (Ki = 4.44 × 10(-6) M), while all the isoflavone ß-L-quinovosides were considerably weak or possessed no inhibition.

16.
Acta Otolaryngol ; 110(5-6): 399-409, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2284915

RESUMO

The intention of this experiment was to investigate whether anatomical variations of the temporal bone such as low middle fossa dura, anterior position of the sigmoid sinus or small mastoid process, which are often seen at surgery in cholesteatoma patients, are caused by inflammation in early childhood. In 7 pigs, 1.5 ml paraffin liquid were instilled into the left tympanic cavity 2 or 7 days after birth in order to produce inflammation of the middle ear and tubal dysfunction. After six and a half months the length and area of the mastoid process were significantly smaller on the left instilled side than on the right, normal side. In all cases there was remarkable hypocellularity and increased thickness of the cortical bone strongly supporting the environmental theory of pneumatization that inflammation suppresses the pneumatization process and growth of the mastoid process.


Assuntos
Processo Mastoide/crescimento & desenvolvimento , Otite Média com Derrame/fisiopatologia , Animais , Processo Mastoide/anatomia & histologia , Processo Mastoide/patologia , Otite Média com Derrame/patologia , Suínos
18.
Nihon Jibiinkoka Gakkai Kaiho ; 92(6): 893-8, 1989 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-2809861

RESUMO

It is generally believed that a cause and effect relationship exists between chronic middle ear inflammatory conditions and suppressed growth of the pneumatized cellulae. We already demonstrated the normal process of pneumatization and the suppressive process of pneumatization in experimental studies using pigs. In that study, the process of suppression of the pneumatization was caused by the continuous inflammatory changes of the epithelium of the middle ear cavity, and the degree of the suppression of the pneumatization was caused by the degree and duration of the air cavity's inflammatory condition at the growing stage of the mastoid process. We also carried out the histological study of the normal process of pneumatization using 100 sides of human fetuses between 16th and 36th week of pregnancy. In these studies the bone metabolisms which were found in the normal processes of pneumatization in pigs and human fetuses were same, and the normal pneumatization occurred at the growing stage of the mastoid process. This growing period of the mastoid is from 0 to 6 months after birth in pigs, and 0 to 15 years in humans. So in humans, we can infer that the suppression of the growth of the cellulae is closely related to a persistent state of otitic inflammation like an otitis media with effusion in the early stages of growth. From these studies, in children who have otitis media with effusion, it will be possible to realize the previous middle ear pathology by the degree of the suppression of pneumatization on x-ray film.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Processo Mastoide/crescimento & desenvolvimento , Otite Média com Derrame/patologia , Adolescente , Envelhecimento/patologia , Ar , Criança , Pré-Escolar , Humanos , Processo Mastoide/diagnóstico por imagem , Otite Média com Derrame/terapia , Radiografia
20.
Laryngoscope ; 96(4): 430-7, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3959703

RESUMO

The suppression of the temporal bone's pneumatized cavities is commonly observed in chronic middle ear inflammatory disease, but this fact has not been explained in respect to its etiology, i.e., whether the poorly pneumatized cavity induces chronic middle ear infection or middle ear inflammatory condition suppresses the pneumatization of cellulae. We studied the effect of middle ear infection and eustachian tubal dysfunction in the early stage of life upon the development of pneumatization of the mastoid using 13 pigs, whose mastoid is comparable to that of man. We used two methods, the eustachian tube stenosis test and the tympanic membrane paraffin infusion test. The present study indicated that in six pigs infection of the middle ear in the early stage of life suppressed the normal development of pneumatization of the mastoid bone in pigs.


Assuntos
Processo Mastoide/crescimento & desenvolvimento , Otite Média/fisiopatologia , Animais , Tuba Auditiva/crescimento & desenvolvimento , Tuba Auditiva/patologia , Processo Mastoide/patologia , Modelos Biológicos , Otite Média/patologia , Suínos , Membrana Timpânica/crescimento & desenvolvimento , Membrana Timpânica/patologia
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