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1.
J Infect Dis ; 228(10): 1400-1409, 2023 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-37161934

RESUMO

BACKGROUND: There is no immunization campaign that currently exist for respiratory syncytial virus (RSV). Seroprevalence studies are critical for assessing epidemiological dynamics before and during an immunization program. A systematic literature review was conducted to summarize the evidence from seroprevalence studies on RSV. METHODS: A systematic search of age-dependent RSV seroprevalence was conducted using the PubMed database and EMBASE. Age-dependent force of infections (FoI) and the decay rate of immunity were estimated. A mixture finite model was used, estimating the age-dependent disease state and the antibody concentrations in susceptible and infected or recovered populations. RESULTS: Twenty-one studies were identified from 15 countries, with studies using enzyme-linked immunosorbent assay being the most represented. Using a catalytic model, the age-dependent force of infection was estimated to be the lowest in infants aged 6 months to 1 year and increased in older age groups. The proportion ever-infected/recovered was estimated to be above 90% by 3 years of age. CONCLUSIONS: The number of seroprevalence studies covering a broad range of ages are limited. The age-dependent FoI indicated that the risk of infection was greatest among those aged >5 years. Additional data using valid assays are required to describe the transmission dynamics of RSV infection.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Lactente , Humanos , Idoso , Pré-Escolar , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Estudos Soroepidemiológicos , Anticorpos Antivirais , Ensaio de Imunoadsorção Enzimática
2.
J Eur Acad Dermatol Venereol ; 33(2): 325-332, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30317671

RESUMO

BACKGROUND: Erythrodermic and generalized pustular psoriasis are rare, difficult to treat forms of psoriasis. In previous reports, we documented 24- and 52-week findings of an open-label, phase 3 trial (UNCOVER-J) of ixekizumab in Japanese patients with erythrodermic or generalized pustular psoriasis; most patients responded to treatment and maintained response through 52 weeks. OBJECTIVE: To assess the long-term (>3 years) efficacy and safety of ixekizumab in Japanese patients with erythrodermic or generalized pustular psoriasis. METHODS: These subgroup analyses were of a partial population of patients from UNCOVER-J (NCT01624233; Sponsored by Eli Lilly and Company), specifically those with erythrodermic psoriasis (N = 8) or generalized pustular psoriasis (N = 5). These patients received 160 mg ixekizumab at Week 0, ixekizumab 80 mg every 2 weeks through Week 12, and ixekizumab 80 mg every 4 weeks thereafter up to Week 244. This regimen is consistent with the regimen approved in Japan for plaque, erythrodermic, and generalized pustular psoriasis and psoriatic arthritis. Efficacy assessments included Global Improvement Score (GIS), Psoriasis Area and Severity Index (PASI), dermal symptoms (for patients with generalized pustular psoriasis), Dermatology Life Quality Index (DLQI) and Itch Numeric Rating Scale (NRS). Safety assessments included treatment-emergent adverse events and adverse events of special interest. RESULTS: Most patients had a GIS of resolved or improved from Week 12 onwards, and all patients had early and sustained improvement in PASI and dermal symptom (generalized pustular psoriasis only) scores. Mean improvements in DLQI and Itch NRS at Week 12 were sustained through Week 244. Ixekizumab was well tolerated over 3 years of treatment in patients with erythrodermic psoriasis or generalized pustular psoriasis, and no new safety concerns were identified. CONCLUSION: These findings suggest that ixekizumab can be an effective long-term treatment option for erythrodermic or generalized pustular psoriasis.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Segurança do Paciente , Psoríase/tratamento farmacológico , Psoríase/patologia , Adulto , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Humanos , Injeções Subcutâneas , Japão , Masculino , Pessoa de Meia-Idade , Psoríase/etnologia , Medição de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
3.
J Eur Acad Dermatol Venereol ; 33(3): 568-576, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30325534

RESUMO

BACKGROUND: Long-term management of moderate-to-severe psoriasis is usually discussed in terms of continuous administration; however, there are many situations in clinical practice where treatment may be withdrawn with subsequent retreatment. OBJECTIVE: To assess the clinical course after ixekizumab treatment withdrawal and retreatment, as well as the effectiveness of ixekizumab retreatment, in Japanese patients with plaque psoriasis. METHODS: This single-arm, open-label study (UNCOVER-J; NCT01624233) comprised 78 patients with plaque psoriasis. After ixekizumab treatment (160-mg loading dose, 80 mg every 2 weeks for the first 12 weeks, and then 80 mg every 4 weeks (IXE Q4W) until Week 52), 70 patients achieved a Psoriasis Area Severity Index (PASI)75 response at Week 52. These 70 patients withdrew from ixekizumab treatment from Weeks 52 to 100. Patients who relapsed (PASI ≤50) during the Treatment Withdrawal Period were retreated with IXE Q4W for 192 weeks. RESULTS: At Weeks 52, 76 and 100, PASI75 response rates were 100%, 26% and 7%; PASI90 response rates were 87%, 11% and 3%; and PASI100 response rates were 53%, 0% and 0%. After treatment withdrawal, 87% of patients relapsed; median time to relapse was 143 days. After 12 weeks of retreatment with IXE Q4W, 83% of relapsed patients achieved PASI75, 68% achieved PASI90 and 25% achieved PASI100; improvements were maintained up to 120 weeks of retreatment. Treatment-emergent adverse events and serious adverse events were reported in 56% and 4% of patients during the Treatment Withdrawal Period, and in 88% and 14% of patients during the Retreatment Period. CONCLUSION: In patients withdrawn from ixekizumab after achieving PASI75, approximately half relapsed within 5 months of withdrawal; however, most patients recaptured response within 12 weeks, and response was maintained for up to 120 weeks of retreatment.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Psoríase/tratamento farmacológico , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Fármacos Dermatológicos/efeitos adversos , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Recidiva , Retratamento , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Suspensão de Tratamento
4.
J Dent Res ; 93(5): 525-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24554541

RESUMO

Corrosion of titanium is the major concern when it is used for dental treatment. This study aimed to investigate the mechanism of the microbiologically induced corrosive properties of titanium. An experimental well was made of polymethyl methacrylate with pure titanium at the bottom. Viable or killed cells of Streptococcus mutans were packed into the well, and pH at the bacteria-titanium interface was monitored with and without glucose. Before and after 90-minute incubation, the electrochemical behavior on the titanium surface was measured by means of a potentiostat. The oxygen concentration under bacterial cells was monitored with oxygen-sensitive fluorescent film. The amount of titanium eluted was measured by inductively coupled plasma-mass spectrometry. The corrosion current and passive current under killed cells were low and stable during 90 min, while those under viable cells increased, regardless of the glucose-induced pH fall. The polarization resistance and oxygen concentration under killed cells were high and stable, while those under viable cells decreased. No elution of titanium was detected. Viable bacterial cells may form 'oxygen concentration cells' through metabolism-coupled oxygen consumption and subsequently induce corrosive properties of the titanium surface.


Assuntos
Materiais Dentários/química , Streptococcus mutans/fisiologia , Titânio/química , Corrosão , Eletroquímica , Eletrólise/instrumentação , Glucose/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Viabilidade Microbiana , Oxigênio/análise , Oxigênio/metabolismo , Polimetil Metacrilato/química , Potenciometria , Espectrofotometria Atômica , Streptococcus mutans/metabolismo , Propriedades de Superfície , Fatores de Tempo
5.
Caries Res ; 47(2): 141-9, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23207788

RESUMO

One preventive effect of topical fluoride application is derived from the fact that fluoride can inhibit bacterial acid production. Furthermore, divalent cations such as Ca(2+) and Mg(2+) increase the binding of fluoride to bacterial cells. These findings suggest that exposure of oral bacteria to fluoride in the presence of divalent cations increases fluoride binding to bacterial cells and subsequently enhances fluoride-induced inhibition of bacterial acid production. This study investigated the effects of fluoride exposure (0-20,000 ppm F) in the presence of Ca(2+) or Mg(2+) prior to glucose challenge on pH fall ability by bacterial sugar fermentation, as well as fluoride binding to bacterial cells by exposure to fluoride, and fluoride release from bacterial cells during bacterial sugar fermentation, using caries-related bacteria, Streptococcus mutans and Streptococcus sanguinis. The pH fall by both streptococci was inhibited by exposure to over 250 ppm F in the presence of Ca(2+) (p < 0.01), whereas in the presence of Mg(2+), the pH fall by S. mutans and S. sanguinis was inhibited after exposure to over 250 and 950 ppm F, respectively (p < 0.05). The amounts of fluoride binding to and released from streptococcal cells increased with the concentration of fluoride the cells were exposed to in the presence of Mg(2+), but were high enough even after 250 ppm F exposure in the presence of Ca(2+). The enhanced inhibition of acid production in the presence of divalent cations is probably due to the improved efficiency of fluoride binding to bacterial cells being improved via these divalent cations.


Assuntos
Cálcio/farmacologia , Cariostáticos/farmacocinética , Fluoretos/farmacocinética , Magnésio/farmacologia , Streptococcus mutans/metabolismo , Streptococcus sanguis/metabolismo , Ácidos/antagonistas & inibidores , Técnicas Bacteriológicas , Cloreto de Cálcio/farmacologia , Cariostáticos/farmacologia , Cátions Bivalentes/farmacologia , Relação Dose-Resposta a Droga , Fermentação/efeitos dos fármacos , Fluoretos/farmacologia , Glucose/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Eletrodos Seletivos de Íons , Cloreto de Magnésio/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Streptococcus mutans/efeitos dos fármacos , Streptococcus sanguis/efeitos dos fármacos , Fatores de Tempo
6.
J Dent Res ; 90(12): 1446-50, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21933936

RESUMO

Physiochemical assessment of the parasite-biomaterial interface is essential in the development of new biomaterials. The purpose of this study was to develop a method to evaluate pH at the bacteria-dental cement interface and to demonstrate physiochemical interaction at the interface. The experimental apparatus with a well (4.0 mm in diameter and 2.0 mm deep) was made of polymethyl methacrylate with dental cement or polymethyl methacrylate (control) at the bottom. Three representative dental cements (glass-ionomer, zinc phosphate, and zinc oxide-eugenol cements) were used. Each specimen was immersed in 2 mM potassium phosphate buffer for 10 min, 24 hrs, 1 wk, or 4 wks. The well was packed with Streptococcus mutans NCTC 10449, and a miniature pH electrode was placed at the interface between bacterial cells and dental cement. The pH was monitored after the addition of 1% glucose, and the fluoride contained in the cells was quantified. Glass-ionomer cement inhibited the bacteria-induced pH fall significantly compared with polymethyl methacrylate (control) at the interface (10 min, 5.16 ± 0.19 vs. 4.50 ± 0.07; 24 hrs, 5.20 ± 0.07 vs. 4.59 ± 0.11; 1 wk, 5.34 ± 0.14 vs. 4.57 ± 0.11; and 4 wks, 4.95 ± 0.27 vs. 4.40 ± 0.14), probably due to the fluoride released from the cement. This method could be useful for the assessment of pH at the parasite-biomaterial interface.


Assuntos
Infiltração Dentária/prevenção & controle , Restauração Dentária Permanente/métodos , Streptococcus mutans/metabolismo , Eletrodos , Fluoretos/análise , Cimentos de Ionômeros de Vidro , Concentração de Íons de Hidrogênio , Cimento de Óxido de Zinco e Eugenol , Cimento de Fosfato de Zinco
7.
Caries Res ; 44(5): 431-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20814202

RESUMO

Oral Bifidobacteriaceae, Bifidobacterium dentium and Bifidobacterium longum, are known to be isolated together with mutans streptococci and lactobacilli from caries lesions, suggesting that these Bifidobacteriaceae are caries associated and acid resistant. This study aimed to investigate effects of acidification on B. dentium and B. longum, and to compare them with those on Streptococcus mutans, Streptococcus sanguinis and Lactobacillus paracasei. Effects of acidification, growth ability in a complex medium at a pH of 4.0-8.0, cell viability in 2-morpholinoethanesulfonic acid monohydrate (MES)-KOH buffer at pH 4.0, as well as stability of intracellular pH (pH(in)) at an extracellular pH of 3.5-8.0 estimated using a fluorescent dye, 5(6)-carboxyfluorescein diacetate N-succinimidyl ester in MES-KOH, 3-(N-morpholino)propanesulfonic acid-KOH or N,N-bis(2-hydroxyethyl)glycine-KOH buffer, were investigated. B. longum grew as well as Streptococcus strains over a wide pH range, whereas B. dentium grew best in the narrow pH range around neutral. The cell viability of B. dentium decreased significantly after 2 h of acidification at a pH of 4.0, but this was significantly less than that of the Streptococcus and Lactobacillus species, whereas B. longum maintained almost 100% viability. The pH(in) was close to the extracellular pH at pH of 5.5-7.5 in the Bifidobacterium and Streptococcus strains, while at a pH of <5.0, the pH(in) was higher than the extracellular pH in all the strains, but the pH(in) maintenance ability of Bifidobacterium strains was higher than that of the Streptococcus strains. The high survival rate and pH(in) maintenance ability of bifidobacteria comparable to that of S. mutans in the acidic environment may account for why bifidobacteria exist as stable species in acidic caries lesions together with mutans streptococci.


Assuntos
Bifidobacterium/crescimento & desenvolvimento , Cárie Dentária/microbiologia , Ácidos , Ácidos Alcanossulfônicos/farmacologia , Técnicas Bacteriológicas , Bifidobacterium/classificação , Bifidobacterium/efeitos dos fármacos , Soluções Tampão , Fenômenos Químicos , Fluoresceínas , Corantes Fluorescentes , Glicina/análogos & derivados , Glicina/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Hidróxidos/farmacologia , Lactobacillus/efeitos dos fármacos , Lactobacillus/crescimento & desenvolvimento , Viabilidade Microbiana/efeitos dos fármacos , Morfolinas/farmacologia , Boca/microbiologia , Compostos de Potássio/farmacologia , Streptococcus/efeitos dos fármacos , Streptococcus/crescimento & desenvolvimento , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/crescimento & desenvolvimento , Fatores de Tempo
8.
Caries Res ; 43(1): 17-24, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19136828

RESUMO

This study evaluated acid production from cooked starch by Streptococcus mutans, Streptococcus sobrinus, Streptococcus sanguinis and Streptococcus mitis, and the effects of alpha-amylase inhibitors (maltotriitol and acarbose) and xylitol on acid production. Streptococcal cell suspensions were anaerobically incubated with various carbohydrates that included cooked potato starch in the presence or absence of alpha-amylase. Subsequently, the fall in pH and the acid production rate at pH 7.0 were measured. In addition, the effects of adding alpha-amylase inhibitors and xylitol to the reaction mixture were evaluated. In the absence of alpha-amylase, both the fall in pH and the acid production rate from cooked starch were small. On the other hand, in the presence of alpha-amylase, the pH fell to 3.9-4.4 and the acid production rate was 0.61-0.92 micromol per optical density unit per min. These values were comparable to those for maltose. When using cooked starch, the fall in pH by S. sanguinis and S. mitis was similar to that by S. mutans and S. sobrinus. For all streptococci, alpha-amylase inhibitors caused a decrease in acid production from cooked starch, although xylitol only decreased acid production by S. mutans and S. sobrinus. These results suggest that cooked starch is potentially acidogenic in the presence of alpha-amylase, which occurs in the oral cavity. In terms of the acidogenic potential of cooked starch, S. sanguinis and S. mitis were comparable to S. mutans and S. sobrinus. Alpha-amylase inhibitors and xylitol might moderate this activity.


Assuntos
Cariogênicos/farmacologia , Cariostáticos/farmacologia , Saliva/enzimologia , Amido/metabolismo , Streptococcus/metabolismo , Álcoois Açúcares/farmacologia , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/farmacologia , Acarbose/farmacologia , Ácidos/metabolismo , Culinária , Carboidratos da Dieta/metabolismo , Inibidores Enzimáticos/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Solanum tuberosum , Streptococcus/efeitos dos fármacos , Xilitol/farmacologia
9.
Oral Microbiol Immunol ; 21(5): 283-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16922926

RESUMO

BACKGROUND/AIMS: This study aimed to investigate the biochemical mechanisms employed by the endodontic pathogen Enterococcus faecalis to confer acid- and alkali-resistance and to compare these with the mechanisms of representative oral streptococci. METHODS: E. faecalis JCM8728, Streptococcus mutans NCTC10449 and Streptococcus sanguinis ATCC10556 were used to assess both acid- and alkali-resistance by examining: (i) growth in complex media; (ii) stability of intracellular pH (pH(in)); (iii) cell durability to leakage of preloaded BCECF (2',7'-bis-(2-carboxyethyl)-5,6-carboxy-fluorescein); and (iv) cell permeability to SYTOX-Green. RESULTS: Growth was initiated by E. faecalis at pH 4.0-11.0, by S. mutans at pH 4.0-9.0 and by S. sanguinis at pH 5.0-9.0. The pH(in) was similar to the extracellular pH in S. mutans and S. sanguinis at pH 5-10, while the pH(in) of E. faecalis was maintained at approximately 7.5-8.5 when extracellular pH was 7.5-10 and was maintained at levels equivalent to the extracellular pH when pH < 7.5. Cell membranes of E. faecalis were resistant to BCECF leakage when extracellular pH was 2.5-12 and to SYTOX-Green permeability at pH 4-10. The cell membrane durability to extracellular pH in E. faecalis was higher than that observed in the Streptococcus strains. CONCLUSION: Compared to S. mutans, E. faecalis was found to be equally resistant to acid and more resistant to alkalis. The results suggest that pH-resistance in E. faecalis is attributed to membrane durability against acid and alkali, in addition to cell membrane-bound proton-transport systems. These characteristics may account for why E. faecalis is frequently isolated from acidic caries lesions and from persistently infected root canals where calcium hydroxide medication is ineffective.


Assuntos
Adaptação Fisiológica , Farmacorresistência Bacteriana/fisiologia , Enterococcus faecalis/crescimento & desenvolvimento , Ácidos/farmacologia , Álcalis/farmacologia , Hidróxido de Cálcio/farmacologia , Permeabilidade da Membrana Celular , Doenças da Polpa Dentária/microbiologia , Enterococcus faecalis/efeitos dos fármacos , Fluoresceínas/metabolismo , Corantes Fluorescentes/metabolismo , Concentração de Íons de Hidrogênio , Testes de Sensibilidade Microbiana , Compostos Orgânicos/metabolismo , Bombas de Próton/metabolismo , Irrigantes do Canal Radicular/farmacologia , Streptococcus mutans/crescimento & desenvolvimento , Streptococcus sanguis/crescimento & desenvolvimento
10.
Oral Microbiol Immunol ; 19(6): 390-4, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15491465

RESUMO

The aim of this study was to isolate and identify alkali-resistant bacteria from the dentin of infected root canals. Bacteria from homogenized dentin powder made up from infected root canal walls from human teeth were cultured on buffer-enriched Brain Heart Infusion agar supplemented with 4% sheep blood (BHI-blood agar), adjusted to pH 7.0, 9.0 or 10.0. Incubation took place for 7 days at 37 degrees C in an anaerobic glove box. Bacterial strains selected according to colony and morphology were subcultured in buffer-enriched BHI broth adjusted to pH 9.0, 10.0 or 11.0 to confirm their growth as alkali-resistant bacteria. Polymerase chain reaction amplification using specific primer sets and 16S rDNA sequence analysis was performed for identification of alkali-resistant isolates. In the present study, 37 teeth extracted from 37 patients were used for preparation of the dentin powder samples. Bacteria were detected in 25 samples when standard BHI-blood agars (pH 7.0) were used. Of these, 29 strains from 15 samples were alkali resistant, 25 strains growing at pH 9.0 and 4 at pH 10.0. The alkali-resistant strains included Enterococcus faecium (10 strains) and Enterococcus faecalis (2 strains), Enterobacter cancerogenus (1 strains), Fusobacterium nucleatum (1 strains), Klebsiella ornithinolytica (2 strains), Lactobacillus rhamnosus (2 strains), Streptococcus anginosus (2 strains), Streptococcus constellatus (3 strains), and Streptococcus mitis (2 strains). Three strains were also identified as bacteria of genus Firmicutes or Staphylococcus at the genus level. The present study showed that many bacterial species in infected root canal dentin were alkali-resistant at pH 9.0 and/or pH 10.0, and belonged mainly to the genus Enterococcus.


Assuntos
Álcalis/farmacologia , Bactérias Anaeróbias/efeitos dos fármacos , Cavidade Pulpar/microbiologia , Necrose da Polpa Dentária/microbiologia , Farmacorresistência Bacteriana , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Infecções Bacterianas/microbiologia , Técnicas de Tipagem Bacteriana , Hidróxido de Cálcio/farmacologia , Meios de Cultura/química , DNA Bacteriano/análise , Dentina/microbiologia , Enterococcus faecalis/efeitos dos fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Pessoa de Meia-Idade
11.
Endoscopy ; 36(4): 306-12, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15057679

RESUMO

BACKGROUND AND STUDY AIMS: We undertook this retrospective study to evaluate the frequency and prognosis of endoscopic treatment of laterally spreading tumors (LSTs) in the rectum. The recurrence rate for lesions of the lower rectum was compared with that of the upper rectum. PATIENTS AND METHODS: During the period from July 1989 to June 2002, a total of 1237 rectal tumors were detected. LSTs accounted for 6.9 % (85/1237) of all rectal tumors. A total of 224 tumors of the lower rectum were detected among the 1237 rectal tumors. LSTs accounted for 16.1 % (36/224) of all the lower rectal tumors. From 85 LST lesions, 67 were evaluated for their prognosis after endoscopic mucosal resection (EMR). Patients whose LSTs had been resected were followed up by endoscopy at the following frequencies: once 15 (22.4 %); twice (more than 1 year), 20 (29.9 %); three times (more than 3 years), 21(31.3 %); and four times or more (more than 5 years), 11 (16.4 %). RESULTS: A total of 67 patients with endoscopically treated LSTs were followed up by endoscopy. We observed recurrences in two lesions of the upper rectum (2/38, 5.3 %) and five lesions of the lower rectum (5/29, 17.2 %) (P = 0.2364); all seven lesions were resected piecemeal. LSTs whose horizontal margin reached the pectinate line frequently recurred in the lower rectum, at a rate of 80 % (4/5). However, all patients were completely cured by additional endoscopic resections, the greatest number of treatments being four. CONCLUSION: For early detection of recurrence and successful endoscopic cure, further colonoscopic examination within a few months after the first treatment is necessary.


Assuntos
Adenoma/cirurgia , Carcinoma/cirurgia , Colonoscopia/métodos , Mucosa Intestinal/cirurgia , Recidiva Local de Neoplasia , Neoplasias Retais/cirurgia , Adenoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Retais/patologia , Reto/patologia , Reto/cirurgia , Estudos Retrospectivos
12.
Environ Sci Technol ; 35(6): 1276-81, 2001 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-11347944

RESUMO

Decomposition of low concentration dichloromethane in nitrogen-based gas was experimentally investigated by a wire-in-tube pulsed corona reactor. Maximum decomposition was found in pure nitrogen, and the decomposition decreased with the increase of oxygen concentration in the gas. The major product detected by FTIR from the decomposition of dichloromethane without oxygen participation was HCI, while CO, CO2, COCl2, and NOx were the main detected products in the presence of oxygen. Aiming at removing the unwanted byproducts from the decomposition reaction, a combination of corona discharge and gas absorption was devised by coating a thin layer of Ca(OH)2 on the inner wall of the corona reactor. It was demonstrated that this kind of combination was capable of scavenging the products of phosgene and nitrogen oxides from the plasma decomposition of dichloromethane.


Assuntos
Poluentes Atmosféricos/química , Cloreto de Metileno/química , Gases , Nitrogênio/química , Compostos Orgânicos , Oxigênio , Volatilização
13.
Dev Biol ; 230(2): 258-77, 2001 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-11161577

RESUMO

Ca2+ entry during electrical activity plays several critical roles in development. However, the mechanisms that regulate Ca2+ influx during early embryogenesis remain unknown. In ascidians, a primitive chordate, development is rapid and blastomeres of the muscle and neuronal lineages are easily identified, providing a simple model for studying the expression of voltage-dependent Ca2) channels (VDCCs) in cell differentiation. Here we isolate an ascidian cDNA, TuCa1, a homologue of the alpha(1)-subunit of L-type class Ca2+ channels. We unexpectedly found another form of Ca2+ channel cDNA (3-domain-type) potentially encoding a truncated type which lacked the first domain and a part of the second domain. An analysis of genomic sequence suggested that 3-domain-type RNA and the full-length type have alternative transcriptional start sites. The temporal pattern of the amount of 3-domain-type RNA was the reverse of that of the full-length type; the 3-domain type was provided maternally and persisted during early embryogenesis, whereas the full-length type was expressed zygotically in neuronal and muscular lineage cells. Switching of the two forms occurred at a critical stage when VDCC currents appeared in neuronal or muscular blastomeres. To examine the functional roles of the 3-domain type, it was coexpressed with the full-length type in Xenopus oocyte. The 3-domain type did not produce a functional VDCC current, whereas it had a remarkable inhibitory effect on the functional expression of the full-length form. In addition, overexpression of the 3-domain type under the control of the muscle-specific actin promoter in ascidian muscle blastomeres led to a significant decrease in endogenous VDCC currents. These findings raise the possibility that the 3-domain type has some regulatory role in tuning current amplitudes of VDCCs during early development.


Assuntos
Canais de Cálcio/genética , Embrião não Mamífero/fisiologia , Transcrição Gênica , Urocordados/embriologia , Urocordados/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Canais de Cálcio/química , Canais de Cálcio/fisiologia , Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo L/genética , Clonagem Molecular , DNA Complementar , Feminino , Impressão Genômica , Dados de Sequência Molecular , Morfogênese , Músculos/embriologia , Oócitos/fisiologia , Estrutura Secundária de Proteína , Splicing de RNA , RNA Mensageiro/análise , Coelhos , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Xenopus laevis
14.
Nihon Ronen Igakkai Zasshi ; 37(12): 974-8, 2000 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-11201187

RESUMO

To examine the difference in functional brain imaging between mild cognitive impairment (MCI) and normal aging, we measured rCBF on functional brain imaging using 123I-IMP single photon emission computed tomography (IMP-SPECT) in 19 MCI patients who progressed to develop AD on follow-up and 23 probable Alzheimer's disease (AD) patients as well as 15 age-matched normal subjects. Baseline MMSE score was 25.3 (SD 1.2) in the MCI group and 17.5 (SD 3.3) in the AD group. The regions of interest (ROI) in the posterior cingulate gyrus, frontal, temporal and parietal cortices were drawn on the image of IMP-SPECT with reference to an individual MRI image. The rCBF ratio was calculated using ROI value in the cerebellum as a reference. Voxel-based analysis was also preformed using statistical parametric mapping (SPM). The rCBF ratio in the posterior cingulate gyrus was significantly reduced in the MCI group (mean 0.956, SD 0.080) and the AD group (mean 0.833, SD 0.118) compared to that in the normal group (mean 1.083, SD 0.084). In the frontal, temporal and parietal cortices, the rCBF ratio was significantly reduced only in the AD group compared to the normal group. At a fixed specificity of 80%, the diagnostic sensitivity in the discrimination between MCI patients and normal subjects was 80.5% when using rCBF ratio in posterior cingulate gyrus. In the SPM analysis, significant reduction of the rCBF in MCI group was observed only in the posterior cingulate gyrus, compared with normal subject group. Our results suggest that MCI patients presenting with a posterior cingulate hypoperfusion are at higher risk for transition from MCI to clinically recognizable AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Transtornos Cognitivos/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/patologia , Progressão da Doença , Humanos , Iofetamina , Análise por Pareamento , Compostos Radiofarmacêuticos
15.
J Neurosci ; 19(16): 6874-86, 1999 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10436045

RESUMO

Na(+) and K(+) channels are the two key proteins that shape the action potentials in neurons. However, little is known about how the expression of these two channels is coordinated. To address this issue, we cloned a Shab-related K(+) channel gene from ascidian Halocynthia roretzi (TuKv2). In this animal, a blastomere of neuronal lineage isolated from the 8-cell embryo expresses single Na(+) channel and K(+) channel genes after neural induction. Expression of a dominant negative form of TuKv2 eliminated the native delayed rectifier K(+) currents, indicating that the entire delayed rectifier K(+) current of the neuronal blastomere is exclusively encoded by TuKv2. TuKv2 transcripts are expressed more broadly than Na(+) channel transcripts, which are restricted to the neuronal lineages. There is also a temporal mismatch in the expression of TuKv2 transcript and the K(+) current; TuKv2 transcripts are present throughout development, whereas delayed rectifier K(+) currents only appear after the tailbud stage, suggesting that the functional expression of the TuKv2 transcript is suppressed during the early embryonic stages. To test if this suppression occurs by a mechanism specific to the TuKv2 channel protein, an ascidian Shaker-related gene, TuKv1, was misexpressed in neural blastomeres. A TuKv1-encoded current was expressed earlier than the TuKv2 current. Furthermore, the introduction of the TuKv2-expressing plasmid into noninduced cells did not lead to the current expression. These results raise the possibility that the expression of TuKv2 is post-transcriptionally controlled through a mechanism that is dependent on neural induction.


Assuntos
Urocordados/fisiologia , Sequência de Aminoácidos , Animais , Blastômeros/fisiologia , Fase de Clivagem do Zigoto , Embrião não Mamífero/fisiologia , Desenvolvimento Embrionário , Feminino , Dados de Sequência Molecular , Neurônios/fisiologia , Neurônios/ultraestrutura , Oócitos/fisiologia , Canais de Potássio/fisiologia , Processamento de Proteína Pós-Traducional , Homologia de Sequência de Aminoácidos , Canais de Sódio/fisiologia , Especificidade da Espécie , Transcrição Gênica , Urocordados/embriologia , Xenopus
16.
J Physiol ; 515 ( Pt 3): 695-710, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10066898

RESUMO

1. Ascidian blastomeres of muscle lineage express voltage-dependent calcium channels (VDCCs) despite isolation and cleavage arrest. Taking advantage of these large developing cells, developmental changes in functional relations between VDCC currents and intracellular Ca2+ stores were studied. 2. Inactivation of ascidian VDCCs is Ca2+ dependent, as demonstrated by two pieces of evidence: (1) a bell-shaped relationship between prepulse voltage and amplitude during the test pulse in Ca2+, but not in Ba2+, and (2) the decay kinetics of Ca2+ currents (ICa) obtained as the size of tail currents. 3. During replacement in the external solution of Ca2+ with Ba2+, the inward current appeared biphasic: it showed rapid decay followed by recovery and slow decay. This current profile was most evident in the mixed bath solution (2 % Ca2+ and 98 % Ba2+, abbreviated to '2Ca/98Ba'). 4. The biphasic profile of I2Ca/98Ba was significantly attenuated in caffeine and in ryanodine, indicating that Ca2+ release is involved in shaping the current kinetics of VDCCs. After washing out the caffeine, the biphasic pattern was reproducibly restored by depolarizing the membrane in calcium-rich solution, which is expected to refill the internal Ca2+ stores. 5. The inhibitors of endoplasmic reticulum (ER) Ca2+-ATPase (SERCAs) cyclopiazonic acid (CPA) and thapsigargin facilitated elimination of the biphasic profile with repetitive depolarization. 6. At a stage earlier than 36 h after fertilization, the biphasic profile of I2Ca/98Ba was not observed. However, caffeine induced a remarkable decrease in the amplitude of I2Ca/98Ba and this suppression was blocked by microinjection of the Ca2+ chelator BAPTA, showing the presence of caffeine-sensitive Ca2+ stores at this stage. 7. Electron microscopic observation shows that sarcoplasmic membranes (SR) arrange closer to the sarcolemma with maturation, suggesting that the formation of the ultrastructural machinery underlies development of the cross-coupling between VDCCs and Ca2+ stores.


Assuntos
Blastômeros/fisiologia , Canais de Cálcio Tipo N , Canais de Cálcio/fisiologia , Canal de Liberação de Cálcio do Receptor de Rianodina/fisiologia , Urocordados/fisiologia , Animais , Bário/farmacologia , Cafeína/farmacologia , Cálcio/metabolismo , Canais de Cálcio/efeitos dos fármacos , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Embrião não Mamífero/fisiologia , Modelos Biológicos , Músculo Esquelético/fisiologia , Receptor Cross-Talk , Canal de Liberação de Cálcio do Receptor de Rianodina/efeitos dos fármacos , Urocordados/embriologia
17.
World J Surg ; 21(7): 694-701, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9276699

RESUMO

Colorectal adenomas and early cancers are grossly classified into three groups: protruded, flush or slightly elevated (so-called flat adenomas), and depressed. Protruded lesions and flat adenomas are not invasive until they are rather large, whereas depressed lesions can invade the submucosa even when very small. It is not difficult to detect protruded and flat adenomas, but depressed carcinomas are often overlooked. Keys to the detection of depressed carcinomas are a slight color change, bleeding spots, interruptions of the capillary network pattern, slight deformation of the colonic wall, shape change of the lesion with insufflation and deflation of air, and interruption of the innominate grooves by the lesion. Spraying of indigo carmine dye helps to clarify the lesions. Pit pattern analysis with magnifying colonoscopy is useful for diagnosis of early colorectal cancer. Pit pattern analysis and histologic examination suggest that depressed carcinomas probably have arisen de novo, without going through an adenomatous step. Some adenomas appear at first to have a depression, but such cancer-mimicking adenomas with pseudodepression must be distinguished from depressed carcinomas because they are quite different in nature. Protruded and flat adenomas can usually be removed with polypectomy or hot biopsy techniques. Depressed carcinomas are treated with an endoscopic mucosal resection (EMR) technique; but when they massively invade the submucosa, surgical resection is indicated. Some neoplastic lesions, which we call laterally spreading tumors, extensively and circumferentially spread along the colonic wall, although they are short in height. They tend to have a rather benign nature despite their large size; therefore EMR or a piecemeal EMR method is indicated.


Assuntos
Colonoscopia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/cirurgia , Endoscopia , Adenoma/diagnóstico , Adenoma/patologia , Adenoma/cirurgia , Carcinoma/diagnóstico , Carcinoma/patologia , Carcinoma/cirurgia , Neoplasias Colorretais/patologia , Diagnóstico Diferencial , Humanos , Mucosa Intestinal/patologia , Invasividade Neoplásica
18.
Nihon Rinsho ; 54(5): 1298-306, 1996 May.
Artigo em Japonês | MEDLINE | ID: mdl-8965355

RESUMO

Protruded polyps can usually be treated with conventional polypectomy technique. Slightly elevated lesions without malignant findings are treated with hot biopsy method if they are small enough (less than 5 mm). In order to treat flat or slightly depressed lesions or slightly elevated lesions larger than 5 mm, endoscopic mucosal resection (EMR) technique has been invented. Cancers confined to the mucosa or those only minimally invading the submucosa can be completely removed with this method. However, if histological analysis of the resected specimen shows that the cancer invades the submucosa massively or permeating the vessels, surgical treatment should be added, because otherwise there would be risk of cancer residue or metastasis. When a lesion is suspected to be a submucosal cancer by endoscopic findings and pit pattern analysis from the beginning, then surgical resection is the treatment of choice. Laterally spreading tumors, especially the homogeneous granular type, are good indication for EMR or endoscopic piecemeal mucosal resection (EPMR). It is important to remove the lesion completely confirming that the resection margin is covered with normal pits.


Assuntos
Neoplasias do Colo/cirurgia , Colonoscopia , Endoscopia , Colectomia/métodos , Neoplasias do Colo/patologia , Endoscopia/métodos , Humanos , Mucosa Intestinal/cirurgia
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