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1.
Rhinology ; 61(1): 47-53, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36306524

RESUMO

BACKGROUND: Empty nose syndrome (ENS) is characterized by paradoxical nasal obstruction that usually occurs after turbinate surgery. Patients with ENS may also experience significant psychiatric symptoms and sleep dysfunction, which negatively affect the quality of life of affected subjects. This study aimed to evaluate sleep impairment and sleepiness in patients with ENS. METHODS: Patients with ENS and control participants were recruited prospectively. The Sino-Nasal Outcome Test-25 (SNOT-25), Empty Nose Syndrome 6-item Questionnaire (ENS6Q), Epworth Sleepiness Scale (EpSS), and modified sleep quality index (MSQI) were used to evaluate the participants before and after nasal surgery. RESULTS: Forty-eight patients with ENS and forty-eight age- and sex-matched control subjects were enrolled. The SNOT-25, ENS6Q, EpSS, and MSQI scores in the ENS group were all significantly higher than those in the control group before and after surgery. After surgery, ENS patients all exhibited significant improvements in SNOT-25, ENS6Q, EpSS, and MSQI scores. Regression analysis revealed that SNOT-25 score was a significant predictor of EpSS and MSQI in preoperative evaluations. ENS patients experiencing daytime sleepiness suffered from significantly more "dryness of nose" and "suffocation" than those not experiencing daytime sleepiness. CONCLUSIONS: Patients with ENS experienced significantly impaired sleep quality and sleepiness. Nasal reconstruction surgery improved the sleep quality of ENS patients. The severity of sleep dysfunction is associated with the severity of ENS symptoms. Recognizing individuals with significant sleep impairment and sleepiness and providing appropriate management are critical issues for ENS patients.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Obstrução Nasal , Doenças Nasais , Humanos , Doenças Nasais/complicações , Doenças Nasais/cirurgia , Doenças Nasais/diagnóstico , Qualidade de Vida , Sonolência , Obstrução Nasal/etiologia , Obstrução Nasal/cirurgia , Obstrução Nasal/psicologia , Síndrome , Nariz
2.
Rhinology ; 60(3): 177-187, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35233583

RESUMO

BACKGROUND: Whether endoscopic surgery for sellar/parasellar disease causes significant deficits in olfactory function remains unclear. We aimed to systematically review the olfactory outcomes in such settings based on the evidence up to date. METHODS: PubMed, EMBASE, and CENTRAL were searched through February 1, 2021. Included studies were limited to endoscopic surgery for sellar/parasellar disease with follow-up olfactory function measured by standardized olfactory testing methods or subjective assessment. The primary outcome was the change in olfactory function after surgery assessed by standardized olfactory testing methods. The secondary outcome was the change in subjective olfactory function. Random-effects model was used in obtaining combine effects. Study quality was assessed using the Newcastleâ€"Ottawa scale. Sensitivity analysis was carried out using the leave-one-out approach, and publication bias was assessed using Egger's test. RESULTS: The results show no significant difference in olfaction assessed by standardized olfactory testing methods at 1-3 months post-surgery (880 patients in 16 studies) or at 6-12 months post-surgery (1320 patients in 16 studies) compared to pre-surgery, whereas a significantly lower subjective olfaction at 3 months was observed. In addition, the lack of significant change in olfaction as assessed by standardized olfactory testing methods was observed regardless of whether patients were treated with or without the nasoseptal flap (NSF) harvesting. Heterogeneity and publication bias were observed, whereas sensitivity analysis showed the meta-analysis results are robust. CONCLUSION: The findings of this updated systematic review and meta-analysis support the conclusion that endoscopic surgery for sellar and parasellar pathology may pose no greater risk of olfactory dysfunction. In addition, the current evidence does not support there is an increased risk of diminished olfaction among patients treated with NSF during surgery.


Assuntos
Transtornos do Olfato , Olfato , Humanos , Transtornos do Olfato/etiologia , Resultado do Tratamento , Endoscopia/métodos , Retalhos Cirúrgicos
3.
J Dent Res ; 99(3): 277-284, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31905313

RESUMO

In clinical dentistry practice, supplemental bone surgery or jawbone defect after tooth extraction must be assisted by a bone-filling material. Cobalt-substituted hydroxyapatite (COHA) effectively promotes bone cell growth, reduces the inflammatory response, and is an antibacterial agent. COHA can therefore be used as an alveolar bone-filling material or guided bone regeneration membrane. Meanwhile, COHA can be used in magnetic resonance imaging (MRI) with negative contrast agents and targeting materials without causing metal interference with the image. Hence, COHA has received increasing amounts of attention in recent years. However, the influence of different cobalt precursors on the synthesized COHA is still unknown. Therefore, COHA synthesized from 3 cobalt precursors (cobalt chloride, cobalt nitrate, and cobalt sulfate) was compared in this study. The results show that COHA synthesized by the precursor with the smallest anion radius, cobalt chloride, has a larger particle size (239 nm) and a higher cobalt ion substitution rate (15.6%). When the cobalt ion substitution rate increases, the MRI has a stronger contrast. Bioactivity data indicate that COHAC is more susceptible to degradation and therefore releases more cobalt ions to contribute to the differentiation of bone cells. Based on these studies, COHAC prepared with the cobalt chloride precursor has a higher cobalt ion substitution rate, faster degradation rate, better image contrast, and better bioactivity. It is therefore the preferred choice of bone-filling material for alveolar bone regeneration.


Assuntos
Regeneração Óssea , Osso e Ossos , Cobalto , Durapatita , Imageamento por Ressonância Magnética
4.
Eye (Lond) ; 28(9): 1080-6; quiz 1087, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25104736

RESUMO

PURPOSE: To evaluate the refractive outcomes in children treated after intravitreal injection of bevacizumab (IVB) for retinopathy of prematurity (ROP). METHODS: A retrospective, bi-centre study of 34 patients (64 eyes) was conducted. The patients were divided into three groups, patients received intravitreal IVB (IVB group), patients received combined IVB and laser treatment (IVB + Laser group), or patients received lens-sparing vitrectomy (IVB + LSV group). Cycloplegic refraction and axial length (AXL) were evaluated at 2 years old. RESULTS: The prevalences of myopia and high myopia were 47.5 and 10.0% in the IVB group, respectively, which were lower than those in the IVB + Laser (82.4 and 29.4%) and IVB + LSV (all 100%) groups (P = 0.001 and P < 0.001). The prevalences of emmetropia in the IVB group, IVB + Laser group, and IVB + LSV group were 50, 5.9, and 0% (P = 0.001). The AXL were similar among all groups. CONCLUSIONS: At the 2-year follow-up, severe ROP patients treated with IVB alone were more likely to remain emmetropic and had lower prevalences of myopia and high myopia. The development of high myopia in severe ROP patients could not be explained by AXL changes but may be associated with abnormalities in the anterior segment.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Miopia/epidemiologia , Retinopatia da Prematuridade/tratamento farmacológico , Comprimento Axial do Olho/patologia , Bevacizumab , Pré-Escolar , Terapia Combinada , Emetropia/fisiologia , Feminino , Seguimentos , Idade Gestacional , Humanos , Recém-Nascido de muito Baixo Peso , Injeções Intravítreas , Fotocoagulação a Laser , Masculino , Prevalência , Refração Ocular/fisiologia , Estudos Retrospectivos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia , Vitrectomia
6.
Eur J Neurol ; 19(5): 733-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22182406

RESUMO

BACKGROUND AND PURPOSE: The clinical features of pituitary adenomas were retrospectively analyzed, focusing on the factors that contribute to the development of pituitary hemorrhage. Although many causes of pituitary adenoma hemorrhage have been identified, it is difficult to distinguish which conditions are truly causative. We determined the independent variables that contribute to pituitary hemorrhage in pituitary adenoma. METHODS: Two hundred and eighty-eight consecutive patients diagnosed as pituitary adenoma were enrolled. These patients underwent tumor removal through endoscopic transsphenoidal approach. The subjects were divided into hemorrhagic and non-hemorrhagic groups, based on magnetic resonance images and histological findings. The predisposing factors were reviewed in the medical records for all patients. Univariate and multivariate analyses were performed to assess the relationships between variables of pituitary adenoma hemorrhage. RESULTS: We investigated 81 patients in whom hemorrhage from pituitary adenoma occurred. The incidence of pituitary hemorrhage was 28.1% (81/288). The predisposing factors surveyed for pituitary hemorrhage were significantly associated with macroadenoma, non-functional adenomas, anticoagulation therapy, end-stage renal disease, dopamine agonist treatment, and underlying malignant disease (all P < 0.05). Sex, age, hypertension, diabetes mellitus, and previous radiation therapy were not related to pituitary hemorrhage. CONCLUSIONS: In this pooled cohort, the predisposing factors of pituitary adenoma characteristic for pituitary hemorrhage were macroadenoma and non-functional adenoma. Patients who received dopamine agonist and anticoagulation therapy are implicated as precipitating factors. Underlying end-stage renal disease and malignant disease are also factors that contribute to pituitary adenoma hemorrhage.


Assuntos
Causalidade , Hemorragia/epidemiologia , Neoplasias Hipofisárias/epidemiologia , Adenoma/complicações , Adulto , Fatores Etários , Idoso , Anticoagulantes/uso terapêutico , Dopaminérgicos/uso terapêutico , Endoscopia/métodos , Feminino , Hemorragia/diagnóstico , Hemorragia/tratamento farmacológico , Hemorragia/etiologia , Humanos , Nefropatias/epidemiologia , Modelos Logísticos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Estatísticas não Paramétricas
7.
AJNR Am J Neuroradiol ; 32(8): 1539-44, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21700793

RESUMO

BACKGROUND AND PURPOSE: To improve the resection rate of unexpected residual pituitary tumor under image guidance, iCT provides a less time-consuming and more convenient approach of promising the safety of the trans-sphenoidal surgery. However, iCT was thought to have worse image quality than MR imaging. This study was designed to determine the predictive concordance of iCT with standard postoperative high-strength MR imaging for the detection of residual tumors. MATERIALS AND METHODS: From February to December 2009, 33 patients with pituitary macroadenomas were enrolled in this prospective study. All patients received endoscopic trans-sphenoidal surgery for tumor removal and underwent iCT before the surgery finished. If an accessible tumor remnant was suspected and resectable, the surgery was continued. To assess the accuracy of intraoperative evaluation of tumor resection, the intraoperative findings were compared with MR imaging findings obtained 2 to 3 months after surgery by individually calculating the residual tumor volume. RESULTS: There were no statistically significant differences in the comparison between iCT and postoperative MR imaging findings (P > .05), and the predictive rates were also high (R(2) value >0.9). The GTR rate in the case of the noninvasive and fresh cases was 89% (17/19). The overall GTR rate was 58% (19/33), the second-look rate was 21% (7/33), and only one-fourth of the recurrent cases reached GTR. CONCLUSIONS: The extent of resection in trans-sphenoidal surgery can be reliably assessed by iCT. Compared with postoperative MR imaging findings, the findings in this study provided quantitative evidence that iCT not only holds significant promise for maximizing the extent of tumor resection but also eliminates the unnecessary blind surgical manipulation, thus increasing the safety of the procedure.


Assuntos
Adenoma/diagnóstico , Adenoma/cirurgia , Cuidados Intraoperatórios , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/cirurgia , Cuidados Pós-Operatórios , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Adulto Jovem
8.
Int J Obes (Lond) ; 35(9): 1165-72, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21224828

RESUMO

BACKGROUND: Obesity is linked to chronic inflammation in white adipose tissue, which is exacerbated by infiltrating macrophages (MΦs). We recently demonstrated that an extract from grape powder (GPE), which is abundant in quercetin (QUE), reduced inflammation in human MΦs and prevented MΦ-mediated inflammation and insulin resistance in human adipocytes. However, we did not know how QUE individually affected these outcomes. OBJECTIVE AND DESIGN: We examined the extent to which QUE prevents inflammation in human MΦs (that is, differentiated U937 cell line) and cross-talk with human adipocytes (that is, primary cultures of newly differentiated human adipocytes). METHODS AND RESULTS: Treatment of MΦs with QUE attenuated the basal expression of inflammatory genes, such as tumor necrosis factor-α, interleukin (IL)-6, IL-8, IL-1ß and interferon-γ inducible protein-10, and cyclooxygenase-2, a marker of prostaglandin production. QUE also attenuated the abundance of phosphorylated c-Jun N-terminal kinase (JNK) and c-Jun, and IκBα degradation in MΦs. Furthermore, conditioned media (CM) obtained from MΦs treated with QUE decreased the capacity of this CM to inflame adipocytes and cause insulin resistance as evidenced by decreased: (1) inflammatory gene expression, (2) phosphorylation of JNK and c-Jun, (3) serine residue 307 phosphorylation of insulin receptor substrate (IRS)-1, 4) protein tyrosine phosphatase-1B gene expression and 5) suppression of insulin-stimulated glucose uptake. CONCLUSION: Taken together, these data suggest that QUE is one of the bioactive components of GPE that prevents inflammation in MΦs and MΦ-mediated insulin resistance in adipocytes.


Assuntos
Adipócitos/efeitos dos fármacos , Antioxidantes/farmacologia , Mediadores da Inflamação/farmacologia , Inflamação , Resistência à Insulina , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Quercetina/farmacologia , Adipócitos/imunologia , Adulto , Comunicação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados , Feminino , Regulação da Expressão Gênica , Humanos , Inflamação/tratamento farmacológico , Inflamação/imunologia , Resistência à Insulina/imunologia , Interleucinas/imunologia , Macrófagos/imunologia , Pessoa de Meia-Idade , Obesidade/tratamento farmacológico , Obesidade/imunologia , Polifenóis/farmacologia , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Vitis/química
9.
Rhinology ; 48(3): 352-7, 2010 09.
Artigo em Inglês | MEDLINE | ID: mdl-21038029

RESUMO

BACKGROUND: Dysregulation of cysteinyl cathepsins and their inhibitors, cystatins (stefins), were implied in progression of tumorgenesis; nevertheless, their role in sinonasal inverted papilloma (IP) is still unrecognized. METHODS: The differential expression of cathepsins and stefins in IP and normal tissues were revealed by data of human Affymetrix U133A gene chips, real-time polymerase chain reaction (PCR) and immunohistochemistry. RESULTS: Among the cathepsins and stefins family, expression of cathepsin S and stefin A were most differentially expressed (down- and up-regulated, respectively) in IP tissue as compared with normal tissues. Their expression levels were validated by real-time PCR, which showed the expression level of cathepsin S was significantly down-regulated, whereas the expression of stefin A was significantly up-regulated in IP tissue compared to normal sinus mucosa. Using immunohistochemistry, expression of cathepsin S was observed in stromal and epithelial area macrophages of normal sinus mucosa, but no obvious expression of cathepsin S was found in IP tissue. In contrast, over-expression of stefin A was present in nearly all layers of the proliferative squamous cells of IP, but expression of stefin A was only detected in a scattered area of normal sinus mucosa. CONCLUSION: Down-regulation of cathepsin S and up-regulation of its endogenous inhibitor, stefin A, were found in IP tissues as compared with their expression level in normal sinus mucosa tissues. The biological significance of inverse expression of both stefin A and cathepsin S in sinonasal IP need further investigation in the future.


Assuntos
Catepsinas/metabolismo , Cistatina A/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Papiloma Invertido/metabolismo , Neoplasias dos Seios Paranasais/metabolismo , Inibidores de Proteases/metabolismo , Adolescente , Adulto , Idoso , Regulação para Baixo/fisiologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/metabolismo , Recidiva Local de Neoplasia/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
10.
Int J Obes (Lond) ; 34(5): 800-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20101247

RESUMO

BACKGROUND: Obesity-associated inflammation is characterized by an increased abundance of macrophages (MPhis) in white adipose tissue (WAT), leading to the production of inflammatory cytokines, chemokines and prostaglandins (PGs) that can cause insulin resistance. Grape powder extract (GPE) is rich in phenolic phytochemicals that possess anti-oxidant and anti-inflammatory properties. OBJECTIVE: We examined the ability of GPE to prevent lipopolysaccharide (LPS)-mediated inflammation in human MPhis and silence the cross-talk between human MPhis and adipocytes. DESIGN: We investigated the effect of GPE pretreatment on LPS-mediated activation of mitogen activated protein kinases (MAPKs), nuclear factor kappa B (NF-kappaB) and activator protein-1 (AP-1), and induction of inflammatory genes in human MPhis (that is, differentiated U937 cells). In addition, we determined the effect of GPE pretreatment of MPhis on inflammation and insulin resistance in primary human adipocytes incubated with LPS-challenged MPhi-conditioned medium (MPhi-CM). METHODS AND RESULTS: Pretreatment of MPhis with GPE attenuated LPS-induction of inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and IL-1beta; chemokines, such as IL-8 and interferon-gamma inducible protein-10 (IP-10); and a marker of PG production, cyclooxygenase-2 (COX-2). Grape powder extract also attenuated LPS activation of MAPKs, NF-kappaB and AP-1 (c-Jun), as evidenced by decreased (1) phosphorylation of c-Jun NH(2)-terminal kinase (JNK) and p38; (2) degradation of IkappaBalpha and activation of an NF-kappaB reporter construct; and (3) phosphorylation of c-Jun and Elk-1. Using LPS-challenged MPhi-CM, GPE pretreatment attenuated MPhi-mediated inflammatory gene expression, activation of an NF-kappaB reporter and suppression of insulin-stimulated glucose uptake in human adipocytes. CONCLUSION: Collectively, these data demonstrate that GPE attenuates LPS-mediated inflammation in MPhis, possibly by decreasing the activation of MAPKs, NF-kappaB and AP-1, and that GPE decreases the capacity of LPS-stimulated MPhis to inflame adipocytes and cause insulin resistance.


Assuntos
Adipócitos/efeitos dos fármacos , Flavonoides/farmacologia , Macrófagos/efeitos dos fármacos , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Vitis/química , Adipócitos/fisiologia , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Humanos , Inflamação/imunologia , Inflamação/prevenção & controle , Resistência à Insulina/imunologia , Lipopolissacarídeos/imunologia , Macrófagos/fisiologia , Polifenóis
11.
Br J Surg ; 93(3): 332-8, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16392107

RESUMO

BACKGROUND: It remains unclear whether interleukin (IL) 6 plays a role in initiating either the inflammatory or antiapoptotic responses in severe acute pancreatitis. This study examined the effect of neutralizing antibody against IL-6 on the induction of pancreatic acinar cell apoptosis and attenuation of the severity of severe acute pancreatitis. METHODS: Experiments were conducted on laboratory mice with severe acute pancreatitis induced by lipopolysaccharide injection following six injections of caerulein at intervals of 6 h. Neutralizing monoclonal anti-IL-6 antibody was administered either 5 min or 2 h after the first caerulein injection. Apoptosis in pancreatic sections was determined by the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick-end labelling method. RESULTS: Administration of caerulein and LPS induced an increase in serum amylase and IL-6 levels, severe acute pancreatitis, pancreatitis-associated lung injury, and phosphorylation of signal transducer and activator of transcription (STAT) 3 in the pancreas. A neutralizing antibody against IL-6 effectively suppressed these responses. Application of IL-6 neutralizing antibody caused the induction of apoptosis in the pancreatic acinar cells of mice with acute pancreatitis. CONCLUSION: Blocking IL-6 suppresses STAT-3 activation in the pancreas and consequently attenuates the severity of severe acute pancreatitis by promotion of pancreatic acinar cell apoptosis.


Assuntos
Apoptose , Interleucina-6/antagonistas & inibidores , Pancreatite/patologia , Amilases/sangue , Animais , Western Blotting , Ceruletídeo/administração & dosagem , Interleucina-6/sangue , Lipopolissacarídeos/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos ICR , Pancreatite/sangue , Fator de Transcrição STAT3/antagonistas & inibidores
12.
Biochem J ; 338 ( Pt 1): 211-9, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-9931318

RESUMO

The seeds of the plant Trichosanthes anguina contain a type I ribosome-inactivating protein (RIP), designated trichoanguin, which was purified to apparent homogeneity by the combined use of ion-exchange chromatographies, i.e. first with DE-52 cellulose and then with CM-52 cellulose. The protein was found to be a glycoprotein with a molecular mass of 35 kDa and a pI of 9.1. It strongly inhibits the protein synthesis of rabbit reticulocyte lysate, with an IC50 of 0.08 nM, but only weakly that of HeLa cells, with an IC50 of 6 microM. Trichoanguin cleaves at the A4324 site of rat 28 S rRNA by its N-glycosidase activity. The cDNA of trichoanguin consists of 1039 nt and encodes an open reading frame coding for a polypeptide of 294 amino acid residues. The first 19 residues of this polypeptide encode a signal peptide sequence and the last 30 residues comprise an extension at its C-terminus. There are four potential glycosylation sites, located at Asn-51, Asn-65, Asn-201 and Asn-226. A comparison of the amino acid sequence of trichoanguin with those of RIPs such as trichosanthin, alpha-momorcharin, ricin A-chain and abrin A-chain reveals 55%, 48%, 36% and 34% identity respectively. Molecular homology modelling of trichoanguin indicates that its tertiary structure closely resembles those of trichosanthin and alpha-momorcharin. The large structural similarities might account for their common biological effects such as an abortifacient, an anti-tumour agent and anti-HIV-1 activities. Trichoanguin contains two cysteine residues, Cys-32 and Cys-155, with the former being likely to be located on the protein surface, which is directly amenable for conjugation with antibodies to form immunoconjugates. It is therefore conceivable that trichoanguin might be a better type I RIP than any other so far examined for the preparation of immunotoxins, with a great potential for application as an effective chemotherapeutic agent for the treatment of cancer.


Assuntos
Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Inibidores da Síntese de Proteínas/isolamento & purificação , Ribossomos/metabolismo , Sementes/química , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Células HeLa , Humanos , Modelos Moleculares , Dados de Sequência Molecular , N-Glicosil Hidrolases/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/toxicidade , Inibidores da Síntese de Proteínas/química , Inibidores da Síntese de Proteínas/toxicidade , Proteínas Inativadoras de Ribossomos , Ribossomos/efeitos dos fármacos , Ribossomos/enzimologia , Sementes/genética , Alinhamento de Sequência , Análise de Sequência , Homologia de Sequência de Aminoácidos
13.
Biophys J ; 76(2): 679-90, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9929473

RESUMO

The soluble S-crystallin constitutes the major lens protein in cephalopods. The primary amino acid sequence of S-crystallin shows an overall 41% identity with the digestive gland sigma-class glutathione transferase (GST) of cephalopod. However, the lens S-crystallin fails to bind to the S-hexylglutathione affinity column and shows very little GST activity in the nucleophilic aromatic substitution reaction between GSH and 1-chloro-2,4-dinitrobenzene. When compared with other classes of GST, the S-crystallin has an 11-amino acid residues insertion between the conserved alpha4 and alpha5 helices. Based on the crystal structure of squid sigma-class GST, a tertiary structure model for the octopus lens S-crystallin is constructed. The modeled S-crystallin structure has an overall topology similar to the squid sigma-class GST, albeit with longer alpha4 and alpha5 helical chains, corresponding to the long insertion. This insertion, however, makes the active center region of S-crystallin to be in a more closed conformation than the sigma-class GST. The active center region of S-crystallin is even more shielded and buried after dimerization, which may explain for the failure of S-crystallin to bind to the immobilized-glutathione in affinity chromatography. In the active site region, the electrostatic potential surface calculated from the modeled structure is quite different from that of squid GST. The positively charged environment, which contributes to stabilize the negatively charged Meisenheimer complex, is altered in S-crystallin probably because of mutation of Asn99 in GST to Asp101 in S-crystallin. Furthermore, the important Phe106 in authentic GST is changed to His108 in S-crystallin. Combining the topological differences as revealed by computer graphics and sequence variation at these structurally relevant residues provide strong structural evidences to account for the much decreased GST activity of S-crystallin as compared with the authentic GST of the digestive gland.


Assuntos
Cristalinas/química , Glutationa Transferase/química , Cristalino/enzimologia , Octopodiformes/metabolismo , Algoritmos , Sequência de Aminoácidos , Animais , Cromatografia de Afinidade , Dimerização , Glutationa/análogos & derivados , Glutationa/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Sefarose/análogos & derivados , Sefarose/metabolismo , Alinhamento de Sequência , Eletricidade Estática
14.
Mol Pharmacol ; 53(6): 1054-61, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9614208

RESUMO

We investigated the mechanisms by which transforming growth factor (TGF)-beta2 inhibited prolactin mRNA expression in GH3 rat pituitary tumor cells. Maximal inhibition was observed with cells exposed to 5 ng/ml TGF-beta2 for 24 hr. Continuous presence of the hormone during the entire period was not necessary because exposure of cells to TGF-beta2 for 20 min was sufficient to trigger the same extent of prolactin mRNA inhibition at 24 hr as with its persistent presence. The action of TGF-beta2 could be abolished by cycloheximide or EGTA, suggesting the requirement of a newly synthesized protein and extracellular Ca2+. The response of prolactin mRNA to TGF-beta2 was inhibited by preincubation of cells with phorbol-12-myristate-13-acetate, which down-regulated protein kinase C (PKC). The activities of both the cytosolic and membrane PKC were significantly reduced at 20 min after TGF-beta2 addition, and inhibition continued to 24 hr, the last time point analyzed. However, the ratio of cytosolic to membrane PKC was not altered by TGF-beta2. Inhibition of PKC did not require the sustained presence of TGF-beta2. In vitro kinase assays of the immunoprecipitated PKC demonstrated that the activities of alpha, epsilon, mu, and zeta isozymes were significantly decreased in the TGF-beta2-treated cells, whereas that of PKClambda was not affected. Western blotting did not reveal any change in PKCepsilon steady state protein levels, suggesting TGF-beta2 inhibits PKC activity through a post-translational mechanism. Our results support that inhibition of PKC activity is an early event mediating TGF-beta2-inhibited prolactin mRNA expression in GH3 cells.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Prolactina/genética , Proteína Quinase C/fisiologia , Fator de Crescimento Transformador beta/farmacologia , Animais , Cálcio/fisiologia , Relação Dose-Resposta a Droga , Isoenzimas/fisiologia , Biossíntese de Proteínas , Proteína Quinase C/antagonistas & inibidores , RNA Mensageiro/análise , Ratos , Fatores de Tempo , Células Tumorais Cultivadas
15.
Am J Hematol ; 58(2): 130-6, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9625581

RESUMO

Primary adrenal lymphoma (PAL) is extremely uncommon. We describe a case of clinically silent non-Hodgkin's B-cell lymphoma of diffuse large cell type with exclusive left adrenal localization. The tumor was discovered by computed tomography (CT) as a 2.5-cm dense mass and diagnosed at autopsy. Literature concerning this unusual neoplasm is reviewed. During the early stage, particularly when the lesion is small, PAL is likely to be missed. This unusual entity should be included in the differential diagnosis of adrenal masses so that early diagnosis may be made and intervention might dramatically affect the clinical outcome.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Linfoma/diagnóstico , Neoplasias das Glândulas Suprarrenais/terapia , Humanos , Linfoma/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Tomografia Computadorizada por Raios X
16.
Plast Reconstr Surg ; 99(1): 122-8, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8982195

RESUMO

Metacarpal hand refers to the hand that has lost its prehensile ability through amputation of all fingers with or without amputation of the thumb. Functional restoration can be achieved by a wide variety of microvascular toe transfer techniques. When deciding which procedure should be used, careful consideration must be given to the level of amputation of the fingers as well as the functional status of the remaining thumb. In this article we propose a classification for the various patterns of the metacarpal hand along with guidelines for selection of the proper toe transfer procedure.


Assuntos
Amputação Traumática/reabilitação , Traumatismos dos Dedos/reabilitação , Polegar/lesões , Dedos do Pé/transplante , Adulto , Traumatismos dos Dedos/classificação , Mãos/fisiologia , Humanos , Masculino , Microcirurgia
17.
Biochem Biophys Res Commun ; 229(1): 65-72, 1996 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-8954084

RESUMO

A new destruxin [destruxin E2 chlorohydrin] was isolated from the culture medium of Metarrhizium anisopliae and its structure was determined by NMR spectroscopy and mass spectrometry. As compared with other destruxins, the new destruxin showed a lower suppressive activity on the production of hepatitis B virus surface antigen in human hepatoma Hep3B cells. NMR study coupled with molecular modeling by computer graphics has revealed that the hydrophobicity nature of the convex surface characteristic of all destruxin molecules plays an important role in their biological activity.


Assuntos
Antivirais/farmacologia , Depsipeptídeos , Antígenos de Superfície da Hepatite B/biossíntese , Fungos Mitospóricos/química , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia , Antivirais/química , Carcinoma Hepatocelular/virologia , Simulação por Computador , Cristalografia por Raios X , Vírus da Hepatite B/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Proteica , Relação Estrutura-Atividade
18.
Plast Reconstr Surg ; 98(1): 146-50, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8657766

RESUMO

Nine cases of hand degloving injuries were treated successfully with arteriovenous shunting technique. Of these nine cases, four were degloved from the wrist level and one from the forearm, three were degloved at the palm and one at the dorsum of the hand. All injuries resulted in distally based skin flaps, which were either superficial to the palmar fascia or within the subcutaneous layer. Lack of active bleeding from the periphery of the avulsed flaps substantiated circulatory compromise before revascularization. Survival of the avulsed flaps was achieved by directing the proximal arterial flow into the venous channel within the avulsed skin flaps. The post-operative care and rehabilitation were straightforward, and functional results were satisfactory.


Assuntos
Derivação Arteriovenosa Cirúrgica/métodos , Traumatismos da Mão/cirurgia , Mãos/irrigação sanguínea , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cirurgia Plástica/métodos
19.
Asian Pac J Allergy Immunol ; 14(1): 1-4, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8980792

RESUMO

Geriatric asthma is characterized by prolonged illness, lower remission rate, poor response to therapy and higher mortality rate. We studied bronchodilator response and methacholine challenge in 25 aged non-smoking asthmatic patients; thirty-two young asthmatic patients were included as control. The elderly patients had poorer baseline pulmonary function and were more responsive to a bronchodilator than the younger patients. The response to bronchoprovocation did not show any difference between the two groups. Our findings suggested that the airways of elderly asthmatics are as sensitive as those of younger patients and should not be under-treated.


Assuntos
Envelhecimento , Asma/tratamento farmacológico , Brônquios/efeitos dos fármacos , Broncodilatadores/uso terapêutico , Cloreto de Metacolina/uso terapêutico , Adulto , Hiper-Reatividade Brônquica , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Capacidade Vital
20.
Biochim Biophys Acta ; 1292(1): 1-8, 1996 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-8547331

RESUMO

Mastoparan-B, a tetradecapeptide isolated from the venom of the hornet Vespa basalis, belongs to the mastoparan analogs of vespid venom with the lysine residues common for all mastoparan family toxins at positions 4, 11 and 12. Here we use 1H-NMR spectroscopy and hybrid distance geometry-simulated annealing calculation to investigate its three-dimensional structure in trifluoroethanol-containing aqueous solution. The calculated structure shows that residues 3-14 adopt an amphiphilic alpha-helical structure in which the residues with hydrophilic side chains (i.e. Lys-4, Ser-5, Ser-8, Lys-11, Lys-12) are located on one side and the residues with hydrophobic side chains (i.e. Leu-3, Ile-6, Trp-9, Ala-10, Val-13, Leu-14) located on the other side of the molecule. The overall structural features a very similar to the conformation of mastoparan-X reconstituted in vesicle [Wakamatsu et al. (1992) Biochemistry 31, 5654-5660] in spite of the substitutions made for eight residues with distinctly different hydrophobicity. These substitutions lead to a larger hydrophobic moment for the alpha-helical segment and further mobilized N-terminal. This study will help reveal the conformational significance of mastoparan toxins with respect to their potency and activity in G protein regulation.


Assuntos
Peptídeos/química , Conformação Proteica , Venenos de Vespas/química , Sequência de Aminoácidos , Animais , Dicroísmo Circular , Proteínas de Ligação ao GTP/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/síntese química , Peptídeos/farmacologia , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Trifluoretanol
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