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1.
Oral Dis ; 23(7): 973-982, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28419681

RESUMO

OBJECTIVE: Oral fungal infection is generally associated with dysbiosis related to antibiotic use, immunodeficiency, or frailty. However, fungal colonization in a typical population without apparent symptoms and its associated conditions are poorly understood. In this study, oral fungal colonization in community-dwelling and independently living elderly populations was evaluated and factors affecting fungal colonization were analyzed. SUBJECTS AND METHODS: The subjects (410; 181 males and 229 females) were 75-99 years of age; those under prior antibiotic use were excluded. Fungal populations in the saliva were evaluated by PCR-based molecular techniques. Body mass index (BMI), smoking habits, and oral health conditions were examined. RESULTS: Salivary fungal amounts exceeded 104  CFU/ml in 63 (15.4%) of 410 subjects. Candida albicans was most frequently detected (98.4%), followed by Candida glabrata (54.0%), and Candida dubliniensis (38.1%) in those subjects with fungi at 104  CFU/ml or over. Fungi at 104  CFU/ml or over in the presence of C. glabrata or C. dubliniensis was significantly associated with low BMI. CONCLUSIONS: Candida albicans, C. glabrata, and C. dubliniensis dominated the oral mycobiome in Japanese community-dwelling elderly. Lower BMI might signify compromised health status and thus could result in susceptibility to specific candidiasis by C. glabrata and C. dubliniensis.


Assuntos
Candida/isolamento & purificação , Nível de Saúde , Micobioma , Saliva/microbiologia , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Vida Independente , Masculino , Saúde Bucal , Fumar
2.
J Oral Rehabil ; 44(2): 89-95, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27973685

RESUMO

The total number of natural teeth was related to swallowing function among older adults; however, limited information is available regarding the impact of occluding pairs of teeth on swallowing function. This study aimed to examine the association between posterior teeth occlusion and dysphagia risk in older nursing home residents. This cross-sectional study included 238 residents aged ≥60 years from eight nursing homes in Aso City, Japan. Swallowing function was evaluated using the modified water swallowing test (MWST); the primary outcome was dysphagia risk (MWST score ≤3). Posterior teeth occlusion was assessed using number of functional tooth units (FTUs), determined based on number and location of the remaining natural and artificial teeth on implant-supported, fixed or removable prostheses. Univariate and multivariate logistic regression analyses were performed to examine the association between posterior teeth occlusion and dysphagia risk, adjusted for the covariates of number of natural teeth, demographic characteristics, comorbidities, physical function, body mass index and cognitive function. Of the 238 subjects, 44 (18·5%) were determined to be at risk of dysphagia based on the MWST scores. The odds ratio (OR) of dysphagia risk decreased in subjects with higher total FTUs [OR = 0·92, 95% confidence interval (CI) 0·87-0·98]. After adjusting for covariates, this association remained significant (OR = 0·90, 95% CI 0·84-0·97). Loss of posterior teeth occlusion was independently associated with dysphagia risk in older nursing home residents. Maintaining and restoring posterior teeth occlusion may be an effective measure to prevent dysphagia.


Assuntos
Transtornos de Deglutição/fisiopatologia , Comportamento Alimentar/fisiologia , Casas de Saúde , Perda de Dente/fisiopatologia , Idoso de 80 Anos ou mais , Estudos Transversais , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/prevenção & controle , Diagnóstico Precoce , Feminino , Avaliação Geriátrica , Humanos , Japão/epidemiologia , Masculino , Higiene Bucal , Medição de Risco , Perda de Dente/complicações
3.
J Oral Rehabil ; 44(12): 982-987, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28965365

RESUMO

The purpose of this study was to clarify the effect of swallowing disorders on functional decline in community-dwelling older adults receiving home care. This was a 1-year follow-up survey of 176 individuals ≥60 years living at home and receiving homecare services, without total dependence in basic daily living activities, in two mid-sized municipalities in Fukuoka, Japan. Functional decline was measured using the Barthel index (BI), and the primary outcome was total dependence in basic daily living activities (BI ≤ 20 points). Swallowing function was assessed using cervical auscultation, and the primary predictor was swallowing disorders. Logistic regression models were used to assess univariate and multivariate associations between baseline swallowing function and functional decline during follow-up. During follow-up 16 (9.1%), the participants became totally dependent in basic daily living activities. The participants with swallowing disorders had 6.41 times higher odds of total dependence in basic daily living activities compared to participants with normal swallowing function. After adjusting for potential confounders, swallowing disorders were significantly associated with higher odds of total dependence in basic daily living activities (odds ratio = 5.21, 95% confidence interval = 1.33-20.44). Regarding swallowing disorders, the corresponding population attributable fraction (%) of the incidence of total dependence in basic daily living activities was 50.4%. The current findings demonstrated that swallowing disorders were associated with greater risk of functional decline in basic daily living activities among older adults living at home and receiving home nursing care. Maintenance and improvement of swallowing function may prevent late-life functional decline.


Assuntos
Transtornos de Deglutição/epidemiologia , Avaliação Geriátrica , Serviços de Assistência Domiciliar , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Transtornos de Deglutição/fisiopatologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Vida Independente , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
4.
Clin Exp Obstet Gynecol ; 44(1): 143-145, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29714885

RESUMO

The authors report a case of cerebral venous and sinus thrombosis (CVST) in a patient receiving a low-dose estrogen-progestin combination (oral contraceptives, OCs) for uterine adenomyosis. She was switched to gonadotropin-releasing hormone agonist (GnRHa) draw-back therapy, which was successfully administered long-term. CASE: The patient was a 38-year-old nulligravida with a history of smoking. She presented to this hospital with dysmenorrhea and postmenstrual lower abdominal pain. Adenomyosis was diagnosed using ultrasound and magnetic resonance imaging. She was instructed to stop smoking and was administered low-dose OCs. CVST occurred 18 months later. OC therapy was halted, and only antiplatelet therapy was administered. After six months, her chief complaint symptoms intensified, therefore GnRHa draw-back therapy was administered after obtaining informed consent. No uterine enlargement was observed, and the abdominal pain resolved. During 2.5 years of therapy, her bone density levels remained within normal limits. CVST did not recur and no other thromboses were observed.


Assuntos
Adenomiose/tratamento farmacológico , Anticoncepcionais Orais Hormonais/efeitos adversos , Fármacos para a Fertilidade Feminina/uso terapêutico , Leuprolida/uso terapêutico , Trombose dos Seios Intracranianos/induzido quimicamente , Adulto , Feminino , Humanos
5.
Oral Dis ; 21(6): 748-54, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25809116

RESUMO

OBJECTIVES: To assess acetaldehyde (ACH) production by bacteria constituting the oral microbiota and the inhibitory effects of sugar alcohols on ACH production. MATERIALS AND METHODS: The predominant bacterial components of the salivary microbiota of 166 orally healthy subjects were determined by barcoded pyrosequencing analysis of the 16S rRNA gene. Bacterial ACH production from ethanol or glucose was measured using gas chromatography. In addition, inhibition by four sugars and five sugar alcohols of ACH production was assayed. RESULTS: Forty-one species from 16 genera were selected as predominant and prevalent bacteria based on the following criteria: identification in ≥95% of the subjects, ≥1% of mean relative abundance or ≥5% of maximum relative abundance. All Neisseria species tested produced conspicuous amounts of ACH from ethanol, as did Rothia mucilaginosa, Streptococcus mitis and Prevotella histicola exhibited the ability to produce ACH. In addition, xylitol and sorbitol inhibited ACH production by Neisseria mucosa by more than 90%. CONCLUSIONS: The oral microbiota of orally healthy subjects comprises considerable amounts of bacteria possessing the ability to produce ACH, an oral carcinogen. Consumption of sugar alcohols may regulate ACH production by oral microbes.


Assuntos
Acetaldeído/metabolismo , Bactérias/metabolismo , Microbiota , Saliva/microbiologia , Adulto , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Técnicas Bacteriológicas , Feminino , Frutose/farmacologia , Glucose/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Sacarose/farmacologia , Álcoois Açúcares/farmacologia , Xilose/farmacologia
6.
Int Endod J ; 48(8): 717-28, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25088120

RESUMO

AIM: To characterize the microbial composition of persistent periapical lesions of root filled teeth using a molecular genetics approach. METHODOLOGY: Apical lesion samples were collected from 12 patients (23-80 years old) who visited the Kyushu University Hospital for apicectomy with persistent periapical lesions associated with root filled teeth. DNA was directly extracted from each sample and the microbial composition was comprehensively analysed using clone library analysis of the 16S rRNA gene. Enterococcus faecalis, Candida albicans and specific fimA genotypes of Porphyromonas gingivalis were confirmed using polymerase chain reaction (PCR) analysis with specific primers. RESULTS: Bacteria were detected in all samples, and the dominant findings were P. gingivalis (19.9%), Fusobacterium nucleatum (11.2%) and Propionibacterium acnes (9%). Bacterial diversity was greater in symptomatic lesions than in asymptomatic ones. In addition, the following bacteria or bacterial combinations were characteristic to symptomatic lesions: Prevotella spp., Treponema spp., Peptostreptococcaceae sp. HOT-113, Olsenella uli, Slackia exigua, Selemonas infelix, P. gingivalis with type IV fimA, and a combination of P. gingivalis, F. nucleatum, and Peptostreptococcaceae sp. HOT-113 and predominance of Streptococcus spp. On the other hand, neither Enterococcus faecalis nor C. albicans were detected in any of the samples. CONCLUSION: Whilst a diverse bacterial species were observed in the persistent apical lesions, some characteristic patterns of bacterial community were found in the symptomatic lesions. The diverse variation of community indicates that bacterial combinations as a community may cause persistent inflammation in periapical tissues rather than specific bacterial species.


Assuntos
Cavidade Pulpar/microbiologia , Periodontite Periapical/microbiologia , RNA Ribossômico 16S/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas Bacteriológicas , Candida albicans/isolamento & purificação , Enterococcus faecalis/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Porphyromonas gingivalis/isolamento & purificação , Tratamento do Canal Radicular , Dente não Vital/microbiologia
7.
J Obstet Gynaecol ; 35(2): 155-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25058627

RESUMO

We found that congenital uterine anomalies have a negative impact on reproductive outcome in recurrent-miscarriage couples, being associated with further miscarriage with a normal embryonic karyotype. There has been no study comparing live birth rates between patients with and without surgery. We conducted a prospective study to prove that surgery for a bicornuate or septate uterus might improve the live birth rate. A total of 170 patients with congenital uterine anomalies suffering two or more miscarriages were examined. The live birth rate after ascertainment of anomalies, cumulative live birth rate and infertility rate, were compared between patients with and without surgery. In patients with a septate uterus, the live birth rate (81.3%) at the first pregnancy after ascertainment of anomalies with surgery tended to be higher than that (61.5%) in those without surgery. The infertility rates were similar in both groups, while the cumulative live birth rate (76.1%) tended to be higher than without surgery (60.0%). Surgery showed no benefit in patients with a bicornuate uterus for having a baby, but tended to decrease the preterm birth rate and the low birth weight. The possibility that surgery has benefits for having a baby in patients with a septate uterus suffering recurrent miscarriage could not be excluded.


Assuntos
Aborto Habitual/epidemiologia , Nascido Vivo/epidemiologia , Útero/anormalidades , Útero/cirurgia , Adulto , Feminino , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Infertilidade Feminina/epidemiologia , Gravidez , Nascimento Prematuro/epidemiologia , Estudos Prospectivos , Anormalidades Urogenitais/cirurgia
8.
Clin Radiol ; 69(8): 880-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24837699

RESUMO

Pancreatic cystic lesions are increasingly being detected incidentally because of the increased use of cross-sectional imaging. Squamous-lined cysts of the pancreas (lymphoepithelial cyst, epidermoid cyst, and dermoid cyst) are rare cystic lesions lined with squamous epithelium. Distinguishing squamous-lined cysts from other cystic lesions of the pancreas is important to avoid unnecessary surgery, because squamous-lined cysts of the pancreas have no malignant potential. The purpose of this review is to describe findings on computed tomography and magnetic resonance imaging and the histopathological characteristics of squamous-lined cysts, and to summarize the key points of differential diagnosis for pancreatic cystic lesions.


Assuntos
Imageamento por Ressonância Magnética/métodos , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Cisto Pancreático/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Criança , Cisto Dermoide/diagnóstico , Diagnóstico Diferencial , Cisto Epidérmico/diagnóstico , Epitélio/diagnóstico por imagem , Epitélio/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias de Células Escamosas/diagnóstico por imagem , Neoplasias de Células Escamosas/patologia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Adulto Jovem
9.
ESMO Open ; 9(4): 102385, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387111

RESUMO

BACKGROUND: The FUTURE trial (UMIN000029294) demonstrated the safety and efficacy of adding palbociclib after fulvestrant resistance in patients with hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) advanced and metastatic breast cancer (ABC/MBC). In this planned sub-study, cancer panel sequencing of cell-free DNA (cfDNA) was utilized to explore prognostic and predictive biomarkers for further palbociclib treatment following fulvestrant resistance. MATERIALS AND METHODS: Herein, 149 cfDNA samples from 65 patients with fulvestrant-resistant disease were analysed at the time of palbociclib addition after fulvestrant resistance (baseline), on day 15 of cycle 1, and at the end of treatment using the assay for identifying diverse mutations in 34 cancer-related genes. RESULTS: During the course of treatment, mutations in ESR1, PIK3CA, FOXA1, RUNX1, TBX3, and TP53 were the most common genomic alterations observed. Analysis of genomic mutations revealed that before fulvestrant introduction, baseline PIK3CA mutations were marginally lower in metastatic aromatase inhibitor (AI)-treated patients compared to adjuvant AI-treated patients (P = 0.063). Baseline PIK3CA mutations were associated with poorer progression-free survival [hazard ratio: 1.62, P = 0.04]. Comparative analysis between baseline and early-changing gene mutations identified poor prognostic factors including early-changing MAP3K1 mutations (hazard ratio: 4.66, P = 0.04), baseline AR mutations (hazard ratio: 3.53, P = 0.04), and baseline PIK3CA mutations (hazard ratio: 3.41, P = 0.02). Notably, the relationship between ESR1 mutations and mutations in PIK3CA, MAP3K1, and TP53 weakened as treatment progressed. Instead, PIK3CA mutations became correlated with TP53 and FOXA1 mutations. CONCLUSIONS: Cancer panel testing for cfDNA identified prognostic and predictive biomarkers for palbociclib add-on therapy after acquiring fulvestrant resistance in patients with HR+/HER2- ABC/MBC.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama , Resistencia a Medicamentos Antineoplásicos , Fulvestranto , Piperazinas , Piridinas , Humanos , Fulvestranto/uso terapêutico , Fulvestranto/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Piperazinas/uso terapêutico , Piperazinas/farmacologia , Feminino , Piridinas/uso terapêutico , Piridinas/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Prognóstico , Idoso , Adulto , Ácidos Nucleicos Livres , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Mutação
10.
J Reprod Immunol ; 156: 103920, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36863074

RESUMO

Antiphospholipid syndrome (APS) is an established cause of recurrent pregnancy loss (RPL). It is necessary to detect persistently positive antiphospholipid antibodies to diagnose APS. This study aimed to explore risk factors for persistent anticardiolipin (aCL) positivity. Women with a history of RPL or with a history of one or more intrauterine fetal deaths after 10 weeks underwent examinations to determine the causes of RPL, including antiphospholipid antibodies. If aCL-IgG or aCL-IgM antibodies were positive, retests were performed at least 12 weeks apart. Risk factors for persistent aCL antibody positivity were retrospectively investigated. The number and percentage of cases above the 99th percentile were 74/2399 (3.1%) for aCL-IgG, and 81/2399 (3.5%) for aCL-IgM. Of the initially tested cases, 2.3% (56/2399) for aCL-IgG and 2.0% (46/2289) for aCL-IgM were ultimately positive above the 99th percentile in retests. Retest values after 12 weeks were significantly lower than the initial values for both IgG and IgM immunoglobulin classes. Initial aCL antibody titers were significantly higher in the persistent-positive group than in the transient-positive group for both IgG and IgM immunoglobulin classes. The cut-off values for predicting persistent positivity of aCL-IgG antibodies and aCL-IgM antibodies were 15 U/mL (99.1 percentile) and 11 U/mL (99.2 percentile), respectively. The only risk factor for persistently positive aCL antibodies is a high antibody titer during the initial test. When the aCL antibody titer in the initial test exceeds the cut-off value, therapeutic strategies can be defined in subsequent pregnancies without waiting for 12 weeks.


Assuntos
Aborto Habitual , Síndrome Antifosfolipídica , Gravidez , Humanos , Feminino , Anticorpos Anticardiolipina , Estudos Retrospectivos , beta 2-Glicoproteína I , Síndrome Antifosfolipídica/diagnóstico , Anticorpos Antifosfolipídeos , Aborto Habitual/diagnóstico , Fatores de Risco , Imunoglobulina G , Imunoglobulina M
11.
J Dent Res ; 102(7): 752-758, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37204134

RESUMO

Ectopic enrichment of oral microbes in the gut is a notable alteration in gut microbial balance. These microbes are likely delivered from the oral cavity with saliva and food; however, evidence of oral-gut microbial transmission is insufficient and needs further investigation. In this observational study, we examined 144 pairs of saliva and stool samples collected from community-dwelling adults to verify the oral-gut microbial link and identify the relevant influencing factors on the increased abundance of oral microbes within the gut. The bacterial composition of each sample was determined using PacBio single-molecule long-read sequencing of the full-length 16S ribosomal RNA gene and amplicon sequence variant (ASV) analysis. Although the bacterial compositions of salivary and gut microbiota were distinctly different, at least 1 ASV was shared between salivary and gut microbiota in 72.9% of subjects. Shared ASVs accounted for 0.0% to 63.1% (median 0.14%) of the gut microbiota in each subject and frequently included abundant Streptococcus salivarius and Streptococcus parasanguinis. Their total relative abundance in the gut was significantly higher in older subjects or those with dental plaque accumulation. The gut microbiota with ≥5% of shared ASVs displayed a higher abundance of Streptococcus, Lactobacillus, and Klebsiella and a lower abundance of Faecalibacterium, Blautia, Megamonas, and Parabacteroides. Our study presents evidence for the translocation of oral bacteria to the gut in community-dwelling adults and suggests that aging and dental plaque accumulation contribute to an increased abundance of oral microbes in the gut, which might be relevant to the compositional shift in the gut commensals.


Assuntos
Placa Dentária , Microbioma Gastrointestinal , Microbiota , Adulto , Humanos , Idoso , Placa Dentária/microbiologia , Bactérias/genética , Boca , RNA Ribossômico 16S/genética
12.
Oral Dis ; 18(8): 771-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22642872

RESUMO

OBJECTIVES: To characterize the global composition of oral fungal populations in frail elderly adults and to investigate the relationship with their health status. MATERIALS AND METHODS: We investigated the fungal populations on the tongue dorsum in 291 institutionalized elderly adults by molecular PCR-based techniques using internal transcribed spacer regions of nuclear ribosomal DNA. RESULTS: Quantitative PCR analysis showed that fungi were present on the tongue dorsum of 128 subjects at ≥10(4) CFU per sample, and 35 of them exceeded 10(5) CFU per sample. Length heterogeneity-PCR analysis and nucleotide sequence determinations showed that Candida albicans was most frequently detected in those subjects with fungi at ≥10(4) CFU per sample (105 subjects), followed by Candida dubliniensis (78), Malassezia restricta (57), and Candida tropicalis (45). Statistical analysis revealed that those subjects with ≥10(5) CFU of fungi other than C. albicans per sample had an increased risk of fever (≥7 febrile days per 12 months) compared with subjects with <10(5) CFU per sample, after adjustment for other fever-associated confounding factors. CONCLUSIONS: These data demonstrate that the oral cavity of the elderly is inhabited by a diverse array of fungi not limited to typical Candida species and they suggest that the diversity in distribution is associated with health status.


Assuntos
Idoso Fragilizado , Fungos/classificação , Institucionalização , Língua/microbiologia , Idoso , Idoso de 80 Anos ou mais , Candida albicans/genética , Candida albicans/isolamento & purificação , Candida tropicalis/genética , Candida tropicalis/isolamento & purificação , Contagem de Colônia Microbiana , DNA Fúngico/análise , Transtornos de Deglutição/classificação , Demência/classificação , Dentaduras , Feminino , Febre/microbiologia , Fungos/genética , Humanos , Malassezia/genética , Malassezia/isolamento & purificação , Masculino , Atividade Motora , Saúde Bucal , Reação em Cadeia da Polimerase , Fatores de Risco , Análise de Sequência de DNA
13.
J Exp Med ; 170(1): 291-6, 1989 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-2787381

RESUMO

The IL-2R is composed of at least two subunits, the p55 (CD25/Tac) and p75 glycoproteins. The p75 IL-2R is expressed preferentially on resting human peripheral blood NK cells, but is not detected on substantial proportions of T and B lymphocytes, monocytes, or granulocytes. Anti-p75 IL-2R mAb substantially inhibits the early events associated with NK cell activation by IL-2, including inhibition of cytotoxic activity and induction of the CD69 early activation antigen. While anti-p55 IL-2R mAb alone failed to substantially inhibit the initial events of IL-2 stimulation, maximal inhibition of IL-2-induced cytotoxicity and proliferation was achieved by combining both anti-p55 IL-2R and anti-p75 IL-2R. Collectively, results from the present studies directly implicate the p75 IL-2R as the structure predominantly responsible for IL-2 activation of NK cells.


Assuntos
Células Matadoras Naturais/imunologia , Ativação Linfocitária , Receptores de Interleucina-2/imunologia , Anticorpos Monoclonais , Complexo Antígeno-Anticorpo/análise , Células Cultivadas , Humanos , Cinética , Receptores de Interleucina-2/biossíntese
14.
J Exp Med ; 171(3): 637-44, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2106566

RESUMO

We have recently established a mAb named TU11 mAb specific for the p75 subunit of human IL-2 receptor (IL-2R). The present study using TU11 mAb demonstrates the IL-2-induced phosphorylation of IL-2Rp75 on tyrosine residues in IL-2-dependent T cells. The tyrosine phosphorylation is mediated by the high affinity IL-2R, correlates with the IL-2-induced cell growth, and rapidly increases during the first 5 min of IL-2 stimulation. Phosphorylation of serine and threonine residues of IL-2Rp75 is also detected, but its IL-2 dependency is not significant during at least the first 5 min. These results suggest some roles of a tyrosine kinase associated with IL-2Rp75 in the IL-2-induced signal-transducing pathway.


Assuntos
Interleucina-2/farmacologia , Receptores de Interleucina-2/metabolismo , Tirosina/metabolismo , Humanos , Fosforilação , Proteínas Tirosina Quinases/fisiologia , Treonina/metabolismo
15.
J Exp Med ; 169(4): 1323-32, 1989 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2784485

RESUMO

A mouse hybridoma cell line, TU27, producing an mAb was established. TU27 mAb reacted with various human and Gibbon ape T cell lines bearing the IL-2R p75 (IL-2Rp75), but not with cell lines expressing only Tac antigen, IL-2Rp55, and numbers of its binding sites on cell surfaces were similar to those of high-affinity IL-2R. Radioimmunoprecipitation with TU27 mAb defined a molecule with a molecular mass of 75 kD on the surface of IL-2Rp75 bearing cells. TU27 mAb completely blocked IL-2 binding to IL-2Rp75 and to the high-affinity IL-2R but not to IL-2Rp55 composing the low-affinity IL-2R. The IL-2-dependent growth of a human T cell line, ILT-Mat, was significantly inhibited by TU27 mAb only at low concentrations of IL-2, and combination of TU27 mAb and H-31 mAb specific for IL-2Rp55 completely inhibited the cell growth even at high concentrations of IL-2. These data strongly suggest that TU27 mAb is specific for the human IL-2Rp75.


Assuntos
Anticorpos Monoclonais/imunologia , Receptores de Interleucina-2/imunologia , Afinidade de Anticorpos , Especificidade de Anticorpos , Reações Antígeno-Anticorpo , Linhagem Celular , Humanos , Técnicas In Vitro , Ativação Linfocitária , Peso Molecular , Testes de Precipitina
16.
J Exp Med ; 170(4): 1445-50, 1989 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-2571670

RESUMO

By using mAb and flow cytometry, a constitutive expression of the p75 IL-2R was revealed in human peripheral blood CD8+ T cells and TCR delta-1+ T cells as well as in CD16+ NK cells. Anti-p75 IL-2R mAb almost completely inhibited the induction of cytolytic activity in these T cells by brief exposure to IL-2, as estimated by anti-TCR/CD3 mAb-targeted cytotoxicity. While anti-p55 IL-2R mAb alone inhibited the response only modestly, maximal inhibition was achieved by combining both anti-p55 and anti-p75 IL-2R mAbs. These results indicate that the p75 IL-2R constitutively expressed on peripheral blood CD8+ T cells and TCR delta-1+ T cells is predominantly responsible for the direct activation of these cells by IL-2.


Assuntos
Ativação Linfocitária , Receptores de Interleucina-2/fisiologia , Linfócitos T/fisiologia , Anticorpos Monoclonais , Reações Antígeno-Anticorpo , Linfócitos T CD4-Positivos/fisiologia , Citotoxicidade Imunológica , Humanos , Técnicas In Vitro , Interleucina-2/farmacologia , Peso Molecular , Receptores de Interleucina-2/ultraestrutura , Linfócitos T/classificação
17.
J Exp Med ; 175(6): 1417-22, 1992 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-1316930

RESUMO

T cell stimulation by the human immunodeficiency virus 1 gp160-derived peptide p18 presented by H-2Dd class I major histocompatibility complex molecules in a cell-free system was found to require proteolytic cleavage. This extracellular processing was mediated by peptidases present in fetal calf serum. In vitro processing of p18 resulted in a distinct reverse phase high performance liquid chromatography profile, from which a biologically active product was isolated and sequenced. This peptide processing can be specifically blocked by the angiotensin-1 converting enzyme (ACE) inhibitor captopril, and can occur by exposing p18 to purified ACE. The ability of naturally occurring extracellular proteases to convert inactive peptides to T cell antigens has important implications for understanding cytotoxic T lymphocyte responses in vivo, and for rational peptide vaccine design.


Assuntos
Produtos do Gene env/metabolismo , Antígenos H-2/imunologia , HIV-1/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Peptidil Dipeptidase A/sangue , Precursores de Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Captopril/farmacologia , Carboxipeptidases/antagonistas & inibidores , Carboxipeptidases/metabolismo , Sistema Livre de Células , Produtos do Gene env/imunologia , Antígenos H-2/genética , Antígenos H-2/isolamento & purificação , Proteína gp160 do Envelope de HIV , Antígeno de Histocompatibilidade H-2D , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/isolamento & purificação , Humanos , Cinética , Células L , Camundongos , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/metabolismo , Precursores de Proteínas/imunologia , Linfócitos T/imunologia , Transfecção , Microglobulina beta-2/metabolismo
18.
J Exp Med ; 189(9): 1383-90, 1999 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-10224278

RESUMO

We molecularly cloned a new Grb2 family member, named Grf40, containing the common SH3-SH2-SH3 motif. Expression of Grf40 is predominant in hematopoietic cells, particularly T cells. Grf40 binds to the SH2 domain-containing leukocyte protein of 76 kD (SLP-76) via its SH3 domain more tightly than Grb2. Incidentally, Grf40 binds to linker for activation of T cells (LAT) possibly via its SH2 domain. Overexpression of wild-type Grf40 in Jurkat cells induced a significant increase of SLP-76-dependent interleukin (IL)-2 promoter and nuclear factor of activated T cell (NF-AT) activation upon T cell receptor (TCR) stimulation, whereas the COOH-terminal SH3-deleted Grf40 mutant lacked any recognizable increase in IL-2 promoter activity. Furthermore, the SH2-deleted Grf40 mutant led to a marked inhibition of these regulatory activities, the effect of which is apparently stronger than that of the SH2-deleted Grb2 mutant. Our data suggest that Grf40 is an adaptor molecule involved in TCR-mediated signaling through a more efficient interaction than Grb2 with SLP-76 and LAT.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte/metabolismo , Proteínas de Membrana , Proteínas Nucleares , Fosfoproteínas/metabolismo , Proteínas/metabolismo , Transdução de Sinais , Linfócitos T/metabolismo , Domínios de Homologia de src , Animais , Sequência de Bases , Sítios de Ligação , Células COS , Linhagem Celular , DNA Complementar , Proteínas de Ligação a DNA/metabolismo , Proteína Adaptadora GRB2 , Células HeLa , Humanos , Interleucina-2/genética , Células Jurkat , Dados de Sequência Molecular , Fatores de Transcrição NFATC , Fosfoproteínas/genética , Proteínas/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Fatores de Transcrição/metabolismo
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