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1.
J Neonatal Perinatal Med ; 11(2): 191-194, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29843264

RESUMO

We present here a late preterm infant with extensive brain lesions resulting from vitamin K deficiency. A female infant was born after 35 weeks of gestation by emergent cesarean section because of non-reassuring fetal status. Her mother had severe eating disorder and recurrent vomiting since early pregnancy. She was immediately intubated and ventilated because she was extremely pale, hypotonic, and non-reactive. Cerebral magnetic resonance imaging immediately after birth showed intraparenchymal hemorrhage in the left frontal lobe and cerebellum, marked cerebral edema, and cerebellar hypoplasia. Coagulation studies of the infant showed hepaplastin test <5%, prolonged PT and APTT, and a marked elevation of protein induced by vitamin K absence or antagonist-II. This case highlighted a potential risk of intracranial bleeding due to maternal vitamin K deficiency and difficulty in its prediction before delivery. Vitamin K supplementation to high risk mothers might be indispensable for preventing severe fetal vitamin K deficiency. Even when coagulation studies in mothers is normal, it is imperative to provide vitamin K supplementation for total protection.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/complicações , Hemorragias Intracranianas/etiologia , Mães , Complicações Hematológicas na Gravidez/sangue , Efeitos Tardios da Exposição Pré-Natal/sangue , Deficiência de Vitamina K/complicações , Vitamina K/uso terapêutico , Adulto , Transtornos da Alimentação e da Ingestão de Alimentos/sangue , Transtornos da Alimentação e da Ingestão de Alimentos/fisiopatologia , Feminino , Humanos , Recém-Nascido , Hemorragias Intracranianas/sangue , Hemorragias Intracranianas/diagnóstico por imagem , Fenômenos Fisiológicos da Nutrição Materna , Gravidez , Complicações Hematológicas na Gravidez/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Resultado do Tratamento , Deficiência de Vitamina K/sangue , Vômito/complicações
2.
Diabetes Obes Metab ; 17 Suppl 1: 47-54, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26332968

RESUMO

Recent advances in methods for making mammalian organs translucent have made possible whole-body fluorescent imaging with single-cell resolution. Because organ-clearing methods can be used to image the heterogeneous nature of cell populations, they are powerful tools to investigate the hierarchical organization of the cellular circadian clock, and how the clock synchronizes a variety of physiological activities. In particular, methods compatible with genetically encoded fluorescent reporters have the potential to detect circadian activity in different brain regions and the circadian-phase distribution across the whole body. In this review, we summarize the current methods and strategy for making organs translucent (removal of lipids, decolourization of haemoglobin and adjusting the refractive index of the specimen). We then discuss possible applications to circadian biology. For example, the coupling of circadian rhythms among different brain regions, brain activity in sleep-wake cycles and the role of migrating cells such as immune cells and cancer cells in chronopharmacology.


Assuntos
Encéfalo/fisiologia , Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Microscopia Intravital/métodos , Neuroimagem/métodos , Imagem Corporal Total/métodos , Animais , Relógios Biológicos/fisiologia , Cronoterapia/métodos , Técnicas Histológicas/métodos , Humanos , Mamíferos/fisiologia , Microscopia de Fluorescência/métodos , Fases do Sono/fisiologia , Vigília/fisiologia
3.
Phytomedicine ; 14(7-8): 546-50, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17084603

RESUMO

Two dihydroflavonol glycosides, engeletin and astilbin, were isolated from an EtOAc extract of the leaves of Stelechocarpus cauliflorus R.E. Fr. (Annonaceae). The inhibitory activity of engeletin against a recombinant human aldose reductase (IC50 value=1.16 microM) was twice that of quercetin as a positive control (2.48 microM), and 23 times greater than that of astilbin (26.7 microM). Engeletin inhibited the enzyme uncompetitively. Astilbin was about as potent as the positive control, quercetin, in its inhibition of advanced glycation end-products formation. These flavonoids displayed therapeutic potential in the prevention and treatment of diabetic complications.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Annonaceae/química , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Extratos Vegetais/farmacologia , Folhas de Planta/química , Flavonóis/química , Flavonóis/farmacologia , Glicosídeos/química , Glicosídeos/farmacologia , Estrutura Molecular , Extratos Vegetais/química
4.
Phytomedicine ; 11(7-8): 652-6, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15636180

RESUMO

Ellagic acid (1) and its two derivatives, 4-O-methylellagic acid (2) and 4-(alpha-rhamnopyranosyl)ellagic acid (3) were isolated as inhibitors of aldose reductase (AR) from Myrciaria dubia (H. B. & K.) McVaugh. Compound 2 was the first isolated from the nature. Compound 3 showed the strongest inhibition against human recombinant AR (HRAR) and rat lens AR (RLAR). Inhibitory activity of compound 3 against HRAR (IC50 value = 4.1 x 10(-8) M) was 60 times more than that of quercetin (2.5 x 10(-6) M). The type of inhibition against HRAR was uncompetitive.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Ácido Elágico/análogos & derivados , Myrtaceae/química , Animais , Ácido Elágico/isolamento & purificação , Ácido Elágico/farmacologia , Humanos , Cristalino/enzimologia , Masculino , Estrutura Molecular , Monossacarídeos/isolamento & purificação , Monossacarídeos/farmacologia , Folhas de Planta/química , Ratos , Ratos Wistar , Proteínas Recombinantes
5.
Cell Death Differ ; 10(12): 1336-47, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12934062

RESUMO

Cortical neurons rapidly die in necrosis due to poor glucose uptake in the low-density (LD) culture under serum-free condition without any supplements. The scanning and transmission electron microscopical analyses characterized the necrosis by membrane disruption, mitochondrial swelling and loss of cytoplasmic electron density. High-glucose treatment delayed the neuronal death by suppressing necrosis, but induced apoptosis through increase in Bax levels, cytochrome c release, caspase-3 activation and DNA ladder formation. Although pyruvate as well as high glucose inhibited necrotic cell death and rapid decrease in cellular ATP levels, possibly related to decreased [(3)H]-2-deoxy glucose uptake under the serum-free condition, it did not induce apoptosis. Protein kinase C inhibitors blocked these changes related to the cell death mode switch. Several neurotrophic factors did not affect the necrosis, but potentiated high-glucose-induced survival activity, while inhibiting cytochrome c release. All these results suggest that high-glucose treatment causes neuronal cell death mode switch by inhibiting necrosis, while inducing apoptosis, which is prevented by neurotrophic factors.


Assuntos
Glucose/metabolismo , Neurônios/metabolismo , Proteína Quinase C/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Anexina A5/farmacologia , Apoptose , Western Blotting , Caspase 3 , Caspases/metabolismo , Morte Celular , Membrana Celular/metabolismo , Células Cultivadas , Córtex Cerebral/embriologia , Corantes/farmacologia , Meios de Cultura Livres de Soro/farmacologia , Citocromos c/metabolismo , Citoplasma/metabolismo , Fragmentação do DNA , Ativação Enzimática , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , L-Lactato Desidrogenase/metabolismo , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Microscopia de Contraste de Fase , Mitocôndrias/metabolismo , Necrose , Ratos , Fatores de Tempo , Fosfolipases Tipo C/metabolismo
6.
Cell Death Differ ; 10(7): 782-90, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12815461

RESUMO

Cortical neurons die in necrosis in the low-density (LD) culture, and in apoptosis in the high-density (HD) culture under the serum-free condition without any supplements. The neuronal death in LD culture was delayed by conditioned medium (CM) factors prepared from the HD culture. The CM switched the cell death mode from necrosis to apoptosis, characterized by various cell death markers and transmission electron microscopy. The CM inhibited the rapid decrease in cellular ATP levels and [3H]-2-deoxy glucose ([3H]-2-DG) uptake in the LD culture. Inhibitors of phospholipase C and protein kinase C effectively abolished the CM-induced elevation of survival activity, [3H]-2-DG uptake and ATP levels, and necrosis-apoptosis switch. All these results suggest that CM caused the cell death mode switch from necrosis to apoptosis through phospholipase C- and protein kinase C-mediated mechanisms.


Assuntos
Apoptose/fisiologia , Neurônios/enzimologia , Proteína Quinase C/metabolismo , Estresse Fisiológico/enzimologia , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Isquemia Encefálica/enzimologia , Isquemia Encefálica/fisiopatologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Córtex Cerebral/enzimologia , Córtex Cerebral/fisiopatologia , Córtex Cerebral/ultraestrutura , Meios de Cultivo Condicionados/farmacologia , Meios de Cultura Livres de Soro/farmacologia , Desoxiglucose/metabolismo , Inibidores Enzimáticos/farmacologia , L-Lactato Desidrogenase/metabolismo , Microscopia Eletrônica , Necrose , Fatores de Crescimento Neural/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Proteína Quinase C/antagonistas & inibidores , Ratos , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia , Estresse Fisiológico/induzido quimicamente , Estresse Fisiológico/fisiopatologia , Fosfolipases Tipo C/antagonistas & inibidores , Fosfolipases Tipo C/metabolismo
7.
Int J Impot Res ; 14(4): 251-5, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12152113

RESUMO

This study was conducted to show the effect of sildenafil on electrostimulation-induced erection in the rat model. Fifteen 12-week-old male Wistar Kyoto rats were used. The intracavernous pressure and arterial blood pressure were simultaneously monitored through electric cavernous nerve stimulation before and after the administration of sildenafil (2 mg/kg). Statistical analysis was performed on maximal intracavernous pressure (MIP), mean arterial blood pressure (MAP), the MIP/MAP and detumescence time. MAP decreased significantly by about 20 mmHg after sildenafil administration. The MIP/MAP increased significantly after sildenafil administration. The effect of sildenafil on the MIP/MAP was marked especially at lower (2-3 Hz) frequencies. The detumescence time significantly increased after sildenafil administration. We have shown that sildenafil is effective for enhancing erection at lower frequencies and prolonging penile erection in rats. After the administration of sildenafil, penile erection would be induced by weak stimuli that will not cause penile erection under normal conditions.


Assuntos
Ereção Peniana/efeitos dos fármacos , Piperazinas/farmacologia , Vasodilatadores/farmacologia , Animais , Pressão Sanguínea , Estimulação Elétrica , Masculino , Modelos Animais , Purinas , Ratos , Ratos Endogâmicos WKY , Citrato de Sildenafila , Sulfonas
8.
Phytomedicine ; 8(5): 377-81, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11695881

RESUMO

Aldose reductase inhibitors were isolated from an extract of the dry fruits of Caesalpinia ferrea Mart. (Leguminosae). Compound 2 was identified as ellagic acid by comparison with a reference sample. The structure of compound 1 was elucidated as 2-(2,3,6-trihydroxy-4-carboxyphenyl) ellagic acid on the basis of spectral evidence, especially 2D-NMR data (HMQC, HMBC and NOESY). These two compounds inhibited aldose reductase in a non-competitive manner.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Caesalpinia , Ácido Elágico/farmacologia , Frutas/química , Extratos Vegetais/farmacologia , Aldeído Redutase/metabolismo , Ácido Elágico/análogos & derivados , Ácido Elágico/química , Espectroscopia de Ressonância Magnética , Padrões de Referência
9.
Chem Pharm Bull (Tokyo) ; 49(10): 1368-71, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11605675

RESUMO

Ursane- and oleanane-type triterpene oligoglycosides, centellasaponins B, C, and D, were isolated from the aerial parts of Centella asiatica (L.) Urban cultivated in Sri Lanka together with madecassoside, asiaticoside, asiaticoside B, and sceffoleoside A. The chemical structures of centellasaponins B, C, and D were determined on the basis of chemical and physicochemical evidence to be madecassic acid 28-O-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside, madasiatic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside, and 3beta,6beta,23-trihydroxyolean-12-en-28-oic acid 28-O-alpha-L-rhamnopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranoside, respectively.


Assuntos
Centella/química , Plantas Medicinais/química , Saponinas/análise , Sequência de Carboidratos , Hidrólise , Dados de Sequência Molecular , Ácido Oleanólico/análogos & derivados , Oligossacarídeos/análise , Extratos Vegetais/análise , Espectrometria de Massas de Bombardeamento Rápido de Átomos , Sri Lanka , Triterpenos/análise , Triterpenos/química
10.
Jpn J Cancer Res ; 92(10): 1026-33, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11676852

RESUMO

The modifying effects of three kinds of fat (corn oil, beef tallow or perilla oil, each at 20% in the diet) on F344 rat prostate carcinogenesis induced by 3,2'-dimethyl-4-aminobiphenyl (DMAB) were investigated. Non-invasive carcinomas of the ventral prostate were induced by DMAB alone and invasive carcinomas of the other prostate lobes and seminal vesicles by DMAB and testosterone propionate (TP). Eight groups of F344 rats were initiated with 50 mg / kg body weight of DMAB at 2-week intervals for the first 20 weeks, four also receiving TP, extended until week 60. The animals received basal chow powder diet or one of three high fat diets throughout the experiment (60 weeks). One further group served as a non-carcinogen-treated control maintained on basal chow powder diet. Beef tallow significantly increased the development of ventral prostate carcinomas with DMAB alone (from 15 to 45%, P < 0.05), while perilla oil reduced the incidence of prostatic intraepithelial neoplasia (PIN) in the ventral lobe of rats given DMA + TP (from 70 to 10%, P < 0.01), but not in those given DMAB alone. No other effects of high fats were observed regarding PIN or invasive cancers of the dorsolateral and anterior prostate or seminal vesicles. A satellite experiment demonstrated that all high fat diets for 4 weeks increased the 5-bromo-2-deoxyuridine (BrdU) labeling index of prostate epithelial cells, suggesting that a high fat intake, irrespective of the fatty acid composition, may accelerate cell kinetics in the prostate. Of the three high fat diets, beef tallow was also found to increase intestinal carcinogenesis. Thus, the present data revealed carcinogenesis in the prostate and intestine to be promoted by beef tallow.


Assuntos
Compostos de Aminobifenil/farmacologia , Óleo de Milho/farmacologia , Gorduras na Dieta/farmacologia , Gorduras/farmacologia , Neoplasias Intestinais/induzido quimicamente , Neoplasias da Próstata/induzido quimicamente , Ácido alfa-Linolênico/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Carcinógenos/efeitos adversos , Carcinógenos/farmacologia , Bovinos , Óleo de Milho/efeitos adversos , Gorduras na Dieta/efeitos adversos , Gorduras/efeitos adversos , Incidência , Neoplasias Intestinais/etiologia , Neoplasias Intestinais/patologia , Masculino , Carne , Tamanho do Órgão/efeitos dos fármacos , Óleos de Plantas , Próstata/efeitos dos fármacos , Próstata/patologia , Neoplasias da Próstata/etiologia , Neoplasias da Próstata/patologia , Ratos , Ratos Endogâmicos F344 , Glândulas Seminais/efeitos dos fármacos , Glândulas Seminais/patologia , Ácido alfa-Linolênico/efeitos adversos
11.
Biosci Biotechnol Biochem ; 65(7): 1673-5, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11515557

RESUMO

The anti-inflammatory and anti-allergic activity of perilla leaf extract was investigated. The oral administration of perilla leaf extract to mice inhibited two types of acute inflammatory models, arachidonic acid-induced ear edema and 12-o-tetradecanoylphorbol-13-acetate-induced ear edema. Oral administration of perilla leaf extract also inhibited the contact dermatitis model, oxazolone-induced ear edema, by affecting sensitization.


Assuntos
Antialérgicos/farmacologia , Anti-Inflamatórios/farmacologia , Magnoliopsida/química , Extratos Vegetais/farmacologia , Administração Oral , Animais , Antialérgicos/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Ácido Araquidônico/toxicidade , Dermatite de Contato/tratamento farmacológico , Modelos Animais de Doenças , Edema/induzido quimicamente , Edema/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos ICR , Oxazolona/toxicidade , Extratos Vegetais/administração & dosagem , Acetato de Tetradecanoilforbol/toxicidade
12.
Biochim Biophys Acta ; 1526(1): 37-43, 2001 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-11287120

RESUMO

Hybrid glycoprotein and neoproteoglycan probes were prepared by coupling various glycoproteins or polysaccharides to peroxidase or biotinyl bovine serum albumin, respectively. Lectins recognizable by the neoglycoconjugate probes were extracted from 16 cultivable mushrooms. Dot-blot assay revealed five extracts to be reactive with only hybrid glycoprotein probes, but others also reacted with neoproteoglycan probes. According to the reactivity pattern with probe screening, the one lectin from Oudemansiella platyphylla extract (OPL) bound best with asialotransferrin-- and asialoagalactotransferrin--peroxidase probes and was isolated using an asialotransferrin column, but it did not bind with other hybrid glycoprotein or neoproteoglycan probes. OPL, consisting of two polypeptides with high homology in the N-terminal amino acid sequences, exhibited weak hemagglutinating activity. Purified OPL specifically bound the beta-GlcNAc probe among various biotinylated polymeric sugar probes, while it exhibited essentially the same binding specificity toward neoglycoconjugate probes as that of the crude extract, showing a preference for the asialobiantennary complex type of N-linked glycans. These results indicate that the neoglycoconjugate probes are valuable in lectin screening.


Assuntos
Acetilglucosamina/química , Agaricales/química , Lectinas/química , Acetilglucosamina/genética , Sequência de Carboidratos , Cromatografia de Afinidade , Glicoproteínas/genética , Lectinas/classificação , Lectinas/genética , Dados de Sequência Molecular , Extratos Vegetais/química , Proteoglicanas/genética
13.
J Biochem ; 126(3): 530-7, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10467168

RESUMO

An N-acetylglucosamine (GlcNAc)/N-acetylneuraminic acid-specific lectin from the fruiting body of Psathyrella velutina (PVL) is a useful probe for the detection and fractionation of specific carbohydrates. In this study, PVL was found to exhibit multispecificity to acidic polysaccharides and sulfatides. Purified PVL and a counterpart lectin to PVL in the mycelium interact with heparin neoproteoglycans, as detected by both membrane analysis and solid phase assay. The pH-dependencies of the binding to heparin and GlcNAc5-6 differ. The heparin binding of PVL is inhibited best by pectin, polygalacturonic acid, and highly sulfated polysaccharides, but not by GlcNAc, colominic acid, or other glycosaminoglycans. Sandwich affinity chromatography indicated that PVL can simultaneously interact with heparin- and GlcNAc-containing macromolecules. Extensive biotinylation was found to suppress the binding activity to heparin while the GlcNAc binding activity is retained. On the other hand, biotinyl PVL binds to sulfatide and the binding is not inhibited by GlcNAc, N-acetylneuraminic acid, or heparin. These results indicate that PVL is a multi-ligand adhesive lectin that can interact with various glycoconjugates. This multispecificity needs to be recognized when using PVL as a sugar-specific probe to avoid misleading information about the nature of glycoforms.


Assuntos
Acetilglucosamina/metabolismo , Agaricales/metabolismo , Heparina/metabolismo , Lectinas/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Pectinas/metabolismo , Sítios de Ligação , Cromatografia de Afinidade , Dicroísmo Circular , Concentração Osmolar , Ligação Proteica , Sulfoglicoesfingolipídeos/metabolismo
14.
J Ethnopharmacol ; 66(2): 159-65, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10433472

RESUMO

Plant samples derived from ethno-directed and random collections were screened to determine their effect on pre-contracted rat aortic tissue. Of the 31 ethno-directed species, four were found to be potent relaxants of vascular smooth muscle. The vasoactive species were Chamguava gentlei, Alseis yucatanensis, Licaria peckii and Nectandra salicifolia. None of the 32 randomly collected samples produced a relaxation response. These data support the hypothesis that ethno-directed collection is a more efficient means of drug discovery than random plant screens.


Assuntos
Fármacos Cardiovasculares/farmacologia , Etnobotânica , Plantas Medicinais/química , Animais , Aorta Torácica/efeitos dos fármacos , Fármacos Cardiovasculares/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Relaxamento Muscular/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
15.
Int J Pediatr Otorhinolaryngol ; 51(3): 207-10, 1999 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-10628550

RESUMO

We report the case of a 14-year-old girl with a large vestibular aqueduct (LVA) in whom hyperbaric oxygen (HBO) therapy was effective for the treatment of sensorineural hearing loss. The patient was referred to Nagoya University Hospital for the treatment of hearing loss on 14 September, 1998, because her right hearing level had declined abruptly on 22 August, 1998, and had not changed for 3 weeks since then in spite of steroid and prostaglandin therapy. Her audiogram revealed bilateral profound deafness of more than 110 dB. She had had profound hearing loss on the left side since she was 9 years old. HBO therapy was performed on 22 occasions from 17 September until 19 October, 1998. During the HBO therapy, her right hearing ability returned almost to the level determined prior to the abrupt loss, 60 dB. We therefore recommend HBO therapy for the treatment of sensorineural hearing loss associated with large vestibular aqueduct syndrome if the hearing ability does not recover following conventional treatment.


Assuntos
Perda Auditiva Neurossensorial/terapia , Oxigenoterapia Hiperbárica , Aqueduto Vestibular/anormalidades , Adolescente , Feminino , Perda Auditiva Neurossensorial/etiologia , Humanos , Síndrome
17.
Auris Nasus Larynx ; 25(1): 13-20, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9512789

RESUMO

We examined electrophysiologic and morphologic changes following low pressure barotrauma in 25 guinea pigs. Compound action potentials (CAPs), cochlear microphonics (CMs), and transiently evoked otoacoustic emissions (TEOAEs) were elicited by tone bursts (1, 2, 4 and 8 kHz) or non-linear clicks immediately following barotrauma. CAP threshold elevations were observed in 19 out of 25 cochleas, mainly at lower stimulus frequencies. Furthermore, CM and TEOAE thresholds were significantly increased, while CAP and CM amplitudes demonstrated reductions at all stimulus frequencies and intensities. CAP N1 latencies exhibited slight elongations at all stimulus frequencies and intensities. The regression coefficient between the mean CAP thresholds of four stimulus frequencies and TEOAE thresholds was statistically significant. Scanning electron microscopy (SEM) study of six electrophysiologically abnormal cochleas revealed stereocilia morphology in four, but no changes in two. We hypothesize that low pressure barotrauma can injure inner ear hair cells through an early threshold shift secondary to dislocation of the basement membrane.


Assuntos
Barotrauma/fisiopatologia , Orelha Interna/lesões , Orelha Interna/fisiopatologia , Estimulação Acústica/métodos , Potenciais de Ação/fisiologia , Animais , Cóclea/lesões , Cóclea/fisiopatologia , Cóclea/ultraestrutura , Potenciais Microfônicos da Cóclea/fisiologia , Eletrofisiologia , Cobaias , Microscopia Eletrônica de Varredura , Emissões Otoacústicas Espontâneas/fisiologia
18.
Biosci Biotechnol Biochem ; 61(8): 1292-5, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9301110

RESUMO

The overproduction of tumor necrosis factor-alpha (TNF-alpha) was suppressed by orally administering a perilla leaf extract (PLE). When mice were successively injected with OK-432, severe TNF-alpha was induced in the serum, but this elevated TNF-alpha level was reduced after an oral administration of PLE (400 microliters/mouse). Oral administration of PLE also inhibited TNF-alpha production that was induced by muramyl dipeptide (500 micrograms/mouse) and OK-432 (3 KE/mouse). These characteristics were obtained from all strains of perilla. The inhibitory activity against TNF-alpha production was heat-stable, and the existence of several active molecules was suggested. When PLE was passed through an ultrafilter, the inhibitory activity against TNF-alpha production was collected in those fractions with a mass of 0.5 to 1 kDa and more than 10 kDa. When PLE was solvent-extracted, the strongest activity was recognized with aqueous preparation, although significant activity was also detected in preparations extracted with n-hexane and ethyl acetate. These findings suggest that the daily use of certain functional foods may be useful for controlling the host defense system.


Assuntos
Folhas de Planta/química , Plantas Medicinais/química , Fator de Necrose Tumoral alfa/biossíntese , Animais , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Temperatura Alta , Indicadores e Reagentes , Japão , Masculino , Camundongos , Camundongos Endogâmicos C3H , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/química
19.
Anticancer Res ; 17(3C): 1939-43, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9216648

RESUMO

Arsenic is a human carcinogen. On the other hand, selenium supplementation can inhibit induction of carcinogenesis by chemical carcinogens. The effect of selenium compounds on the cytotoxicity of dimethylarsinic acid (DMA) and on the induction of tetraploidy by DMA were studied using Chinese hamster V79 cells. Two selenium compounds were tested, sodium selenite and trimethylselenonium iodide (TMSeI). Trimethylselenonium is a major excretory product of selenite metabolism. The cytotoxicity of sodium selenite was 1000-fold greater than that of TMSeI. The cytotoxicity of DMA was about the same as that of TMSeI. The mitotic index for DMA administration was increased by these selenium compounds at low concentrations and decreased by them at high concentrations. The tetraploid index for DMA decreased with increasing concentrations of these selenium compounds. Tetraploidy is a form of aneuploidy, and aneuploidy is known to induce carcinogenesis. The finding that selenium inhibited induction of tetraploidy by DMA may yield clues to the role of selenium in the chemoprevention of carcinogenesis by chemical carcinogens.


Assuntos
Aneuploidia , Ácido Cacodílico/toxicidade , Carcinógenos , Índice Mitótico/efeitos dos fármacos , Compostos de Selênio/farmacologia , Selenito de Sódio/farmacologia , Animais , Anticarcinógenos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Humanos
20.
Cancer ; 79(8): 1487-93, 1997 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-9118028

RESUMO

BACKGROUND: The nonpromoting effect of olive oil on colon carcinogenesis has been attributed to its high oleic acid content, whereas a positive association of monounsaturated fat in beef tallow with colon tumors has been reported. The effect of constituents other than fatty acids could not be neglected in these experiments. In order to minimize the effects of minor constituents in the oils, the authors compared conventional safflower oil with oil from a mutant strain of safflower that is rich in oleic acid. METHODS: ICR mice were treated with 1,2-dimethylhydrazine (DMH, 20 mg/kg body weight every week for 12 weeks) and then were fed either a high-fat diet (23.5% by weight), containing safflower oil (HF-LA) or high-oleic safflower oil (HF-OA), or a low-fat diet (5% by weight), containing safflower oil (LF-LA) or high-oleic safflower oil (LF-OA). The test diets were continued until termination of the experiment at 30 weeks after the first administration of DMH. Fatty acid composition of colon phospholipids was determined by gas-liquid chromatography-mass spectrometry. RESULTS: Tumor multiplicity in animals fed the HF-OA diet was indistinguishable from that in animals fed LF-LA or LF-OA. In contrast, animals fed the HF-LA diet had a significantly higher incidence of colon tumors (mostly adenocarcinomas) than the other groups. Fatty acid profiles of colon phospholipids reflected those of the diet. Animals fed a HF-LA diet showed a marked decrease of nervonic acid (C24:1, n-9) in the colon sphingomyelin. CONCLUSIONS: These data indicate that oleic acid does not enhance DMH-induced colon carcinogenesis in mice, even when they are fed a high-fat diet.


Assuntos
Neoplasias do Colo/etiologia , Óleo de Cártamo/efeitos adversos , 1,2-Dimetilidrazina , Animais , Testes de Carcinogenicidade , Carcinógenos , Colo/química , Neoplasias do Colo/induzido quimicamente , Dimetilidrazinas , Ingestão de Alimentos , Feminino , Camundongos , Camundongos Endogâmicos ICR , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/etiologia , Fosfolipídeos/química , Óleo de Cártamo/administração & dosagem , Óleo de Cártamo/química , Aumento de Peso
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