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1.
Immunol Lett ; 114(1): 46-51, 2007 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-17949824

RESUMO

Increasing evidence supports a propensity towards inflammation in Alzheimer's disease (AD) pathogenesis. In our previous studies we observed high levels of IL-16, IL-18 and TGF-beta1 mRNA expression in monocyte-macrophages of the peripheral blood of AD patients. The aim of this investigation was to determine the plasma levels of IL-12, IL-16, IL-18 and TGF-beta1 in AD patients at different stages of the disease and to correlate the production of these cytokines with the disease progression. The levels of IL-12, IL-16, IL-18 and TGF-beta1 resulted higher in AD-mild patients, were slightly lower in AD-moderate patients, whereas no significant difference was observed between AD-severe patients and non-demented age-matched subjects. The correlation values between cytokine plasma levels were dependent on the disease progression. Our data indicate that plasma levels of these inflammatory molecules follow the degree of AD suggesting a gradual decline of immune responsiveness in AD.


Assuntos
Doença de Alzheimer/imunologia , Interleucinas/sangue , Fator de Crescimento Transformador beta1/sangue , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/fisiopatologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
J Clin Pathol ; 59(2): 211-5, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16443741

RESUMO

AIMS: To determine whether the G(-174)C interleukin 6 (IL-6) polymorphism influences the development of peripheral arterial disease (PAD) in individuals with type 2 diabetes. This was investigated by comparing the distribution of G(-174)C genotypes between patients with type 2 diabetes and PAD (PAD+) and those with type 2 diabetes but without PAD (PAD-). Plasma concentrations of IL-6, fibrinogen, C reactive protein (CRP), and vascular endothelial growth factor (VEGF) were also compared in PAD+ and PAD- patients. METHODS: Blood samples were collected from 146 PAD+ and 144 PAD- patients. SfaNI was used to determine the G(-174)C genotype. Plasma concentrations of IL-6, fibrinogen, CRP, and VEGF were measured by an enzyme linked immunosorbent assay. RESULTS: The GG genotype was more common in PAD+ patients than in PAD- patients. PAD+ patients also had increased mean plasma concentrations of IL-6, fibrinogen, CRP, and VEGF compared with PAD- patients. Mean plasma concentrations of IL-6, fibrinogen, and CRP in both PAD+ and PAD- patients were higher in those with the GG genotype than in those with the GC or CC genotypes. In contrast, mean plasma concentrations of VEGF in PAD+ and PAD- patients were not significantly different between those with different G(-174)C genotypes. CONCLUSIONS: These results support a model in which the GG genotype promotes PAD development among individuals with type 2 diabetes by inducing increased release of IL-6. Higher concentrations of IL-6 among those with the GG genotype is associated with increased plasma concentrations of fibrinogen and CRP.


Assuntos
Diabetes Mellitus Tipo 2/genética , Angiopatias Diabéticas/genética , Interleucina-6/genética , Doenças Vasculares Periféricas/genética , Polimorfismo Genético , Idoso , Proteína C-Reativa/análise , Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/sangue , Feminino , Fibrinogênio/análise , Predisposição Genética para Doença , Genótipo , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/sangue , Fator A de Crescimento do Endotélio Vascular/sangue
3.
Clin Ter ; 157(6): 531-9, 2006.
Artigo em Italiano | MEDLINE | ID: mdl-17228853

RESUMO

A comprehensive bibliographical retrieval of case reports on "airborne contact dermatitis" (ACD) was performed. The present review deals with the first cases published in 1986, 1991, 2001 by Huygens as well as by Dooms-Goossens, and continues with the other pertaining clinical presentations until to day. Solid particles, rather than gases or droplets, are the most frequently reported causes of ACD.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Poluentes Atmosféricos/efeitos adversos , Dermatite de Contato/etiologia , Dermatite Ocupacional/etiologia , Dermatite Alérgica de Contato/etiologia , Humanos , Exposição Ocupacional/efeitos adversos
4.
Diabetes ; 47(1): 32-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9421371

RESUMO

Previous studies have shown that anti-gamma-interferon (IFN-gamma) antibody reduces the frequency of autoimmune IDDM in the DP-BB rat. We tested the effects of systemically administered recombinant rat IFN-gamma in both DP-BB and DR-BB rats. Unexpectedly, IFN-gamma markedly reduced the incidence of IDDM as compared with control rats when administered six times per week at a dosage of 280,000 U between ages 30-35 to 105 days or ages 60-64 to 105 days. A lower dosage (28,000 U on alternate days) was also protective when administered to DP-BB rats between birth and age 60 days. However, long-lasting protection against IDDM development over the 1-year study period was achieved only by the highest dosage of IFN-gamma administered from age 30 to 105 days. Ex vivo production of tumor necrosis factor-alpha from splenic lymphoid cells (SLCs) and peritoneal macrophages of the rats treated with IFN-gamma was comparable with that of controls; however, SLCs from the IFN-gamma-treated animals secreted lower amounts of IFN-gamma after stimulation with concanavalin A. IFN-gamma treatment also markedly reduced the frequency of phenotypically activated SLC-expressing class II antigens and interleukin-2 receptor. Finally, in agreement with the observed antidiabetogenic effects, exogenously administered IFN-gamma induced neither insulitis nor IDDM development in DR-BB rats, a subline of DP-BB rats in which autoimmune diabetes rarely occurs spontaneously but can be induced by administration of polyinosinic-polycytidilic acid.


Assuntos
Diabetes Mellitus Experimental/prevenção & controle , Diabetes Mellitus Tipo 1/prevenção & controle , Hipoglicemiantes/farmacologia , Interferon gama/farmacologia , Envelhecimento/fisiologia , Animais , Concanavalina A/farmacologia , Diabetes Mellitus Experimental/epidemiologia , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/fisiopatologia , Relação Dose-Resposta a Droga , Feminino , Antígenos de Histocompatibilidade Classe II/análise , Antígenos de Histocompatibilidade Classe II/metabolismo , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Imunossupressores/farmacologia , Incidência , Injeções Intraperitoneais , Interferon gama/administração & dosagem , Interferon gama/metabolismo , Interferon gama/uso terapêutico , Macrófagos Peritoneais/citologia , Macrófagos Peritoneais/metabolismo , Masculino , Fenótipo , Distribuição Aleatória , Ratos , Ratos Endogâmicos BB , Receptores de Interleucina-2/análise , Receptores de Interleucina-2/metabolismo , Proteínas Recombinantes , Baço/citologia , Baço/metabolismo , Tacrolimo/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
5.
Minerva Gastroenterol Dietol ; 51(2): 165-70, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15990705

RESUMO

AIM: It has been previously suggested that t(14;18) translocation of bcl-2 to the immuno-globulin heavy chain (IgH) locus may contribute to pathogenesis of lymphoproliferative disorders related to hepatitis C virus (HCV) infection, including type II mixed cryoglobulinemia (MC). METHODS: In this study, the presence or absence of t(14;18) translocation was determined in tumor biopsy specimens and peripheral blood mononuclear cells (PBMCs) for 48 NHL patients with chronic HCV infection. RESULTS: In tumor biopsy specimens from 32 HCV-positive NHL patients, bcl-2/IgH translocation was detected in 1 of 13 patients with MC syndrome (7.7%) and 3 of 19 patients without MC syndrome (15.8%). In PBMCs from 23 HCV-positive NHL patients, this translocation was observed in 3 of 6 patients with MC syndrome (50%) and 4 of 17 patients without MC syndrome (23.5%). Interestingly, bcl-2/IgH translocation was found in 2 extranodal marginal zone B-cell lymphoma tissues from HCV-infected patients. CONCLUSIONS: However, additional studies are required to better clarify the relationship between this translocation and extranodal marginal zone B-cell lymphoma development. Although the frequency of bcl-2/IgH translocation in PBMCs from patients with chronic HCV infection is higher than that of other NHL patients, this increased translocation rate remains to be elucidated.


Assuntos
Genes bcl-2/genética , Hepatite C Crônica/complicações , Cadeias Pesadas de Imunoglobulinas/genética , Linfoma não Hodgkin/genética , Linfoma não Hodgkin/virologia , Translocação Genética , Adulto , Idoso , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 18 , Feminino , Frequência do Gene , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/genética
6.
Mech Ageing Dev ; 122(10): 1059-72, 2001 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-11389924

RESUMO

Growth factors stimulate astroglial and neuronal proliferation and differentiation in culture. Estrogens markedly influence astroglia, and are key factors participating in neurodegeneration. The aim of the present study was to investigate interactions between estradiol (E2) and epidermal growth factor (EGF) during astroglia development, maturation and differentiation in culture. DNA or RNA labeling in 16 or 40 or 60 days in vitro (DIV) astrocyte cultures treated for 24 or 48 h with EGF and/or E2 was evaluated. A significant increase in DNA labeling in 16 DIV astrocyte cultures treated for 24 h with EGF (5 ng/ml) and E2 (1 nM) was found. EGF (5 or 10 ng/ml) addition in the last 24 h in 48 h E2 (1 or 5 nM)-treated astrocyte cultures at 16 DIV caused a slight, but significant increase in DNA labeling. No differences in RNA labeling were observed in 16 DIV astrocyte cultures treated for 24 or 48 h with EGF (5 or 10 ng/ml) in the presence of E(2) (1 or 5 nM). A significant stimulation in DNA labeling was shown in 40 DIV astrocyte cultures treated for 48 h with E2 (1 or 5 nM) in the presence of EGF (5 or 10 ng/ml) added in the last 24 h. In well differentiated astroglial cell cultures (60 DIV), DNA labeling was remarkably increased after 24 h treatment with 1 nM E2 or 5 ng/ml EGF. Co-addition of 1 nM E2 and 5 ng/ml EGF for 24 h reduced [methyl-(3)H]thymidine incorporation, when data are compared to E2- or EGF-treated cultures. Addition of EGF in the presence of E2 for 48 h or only in the last 24 h caused a significant decrease of [methyl-(3)H]thymidine incorporation in comparison with EGF-treated cultures at 60 DIV or with untreated cultures. Treatment of cultures for 24 h with EGF (5 or 10 ng/ml) alone or in combination with E2 (1 or 5 nM) induced a strong increase of RNA labeling in 60 DIV astrocyte cultures. Addition for 48 h of E2 (1 or 5 nM) or EGF (5 or 10 ng/ml) alone or in association stimulated significantly RNA labeling in astrocyte cultures at 60 DIV. When 60 DIV astrocyte cultures were treated for 48 h with E2 (1 or 5 nM) in the presence of EGF (5 or 10 ng/ml) added only in the last 24 h, a potentiating effect of RNA labeling was observed. The above results suggest that interaction between growth factors and estrogens may contribute to regulate astroglia development, maturation and differentiation.


Assuntos
DNA/biossíntese , Fator de Crescimento Epidérmico/metabolismo , Estradiol/metabolismo , RNA/biossíntese , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Diferenciação Celular , Divisão Celular , Células Cultivadas , Fator de Crescimento Epidérmico/farmacologia , Estradiol/farmacologia , Marcação por Isótopo , Timidina/farmacocinética , Uridina/farmacocinética
7.
Fertil Steril ; 69(1): 37-40, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9457929

RESUMO

OBJECTIVE: To evaluate the expression of alpha6 and beta4 integrin subunits on surface and glandular endometrium throughout the menstrual cycle and during early pregnancy. SETTING: Second Department of Obstetrics and Gynecology, University of Catania, Catania, Italy. PATIENT(S): Thirty-two women. Nineteen of the women regularly menstruated in different phases of the cycle, and 13 were in the sixth to ninth week of gestation and required voluntary abortion. INTERVENTION(S): Endometrial specimens collected during endometrial biopsy, hysterectomy, or voluntary abortion. MAIN OUTCOME MEASURE(S): Immunohistochemical staining for alpha6 and beta4 integrin subunits in endometrial tissues. RESULT(S): Both subunits (poorly expressed in preimplantation days) reached a significant peak on the endometrial surface during the implantation window, which tended to disappear in the postimplantation phase. On glandular endometrium they exhibited an opposite trend, showing high levels in the preimplantation and postimplantation days, whereas their expression decreased during the implantation window. The two subunits tended to disappear in early pregnancy. CONCLUSION(S): alpha6 and beta4 integrin subunits are uniformly distributed and highly expressed on the endometrial surface during the implantation window; they decreased dramatically in the postimplantation phase. These results could suggest involvement of integrin-extracellular matrix components in blastocyst-endometrium interaction during the early stages of implantation.


Assuntos
Antígenos CD/metabolismo , Endométrio/metabolismo , Ciclo Menstrual/metabolismo , Gravidez/metabolismo , Adulto , Desenvolvimento Embrionário/fisiologia , Feminino , Humanos , Imuno-Histoquímica/métodos , Integrina alfa6 , Integrina beta4 , Pessoa de Meia-Idade , Primeiro Trimestre da Gravidez , Coloração e Rotulagem , Distribuição Tecidual
8.
Arch Gerontol Geriatr ; 18(2): 141-7, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-15374307

RESUMO

The proliferative capacity of the immune system is impaired in elderly subjects and the expression of various genes involved in cell cycle progression is reduced in PHA stimulated lymphocytes during the aging process. Macrophages play a fundamental role in the immune system response. It has recently been demonstrated that the process of macrophage activation is accompanied by a rapid, transient rise of ornithine decarboxylase (ODC) mRNA levels. In fact, the ODC gene seems to be involved in macrophage activation and differentiation. The authors demonstrated that the steady-state levels of ODC mRNA and the correlated superoxide anion production are lower in the monocytes of elderly subjects with respect to those in young subjects used as control. These results confirmed the impaired immune function of the elderly.

9.
Arch Gerontol Geriatr ; 22 Suppl 1: 469-71, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-18653079

RESUMO

The serum interleukin-2 (IL-2) concentrations were evaluated in healthy elderly patients, enrolled under the SENIEUR protocol, and healthy adult controls. The aim of the study was to ascertain whether the reduced immune response, described during aging, is linked to deficient production of IL-2 or to its receptorial deficit, or if the reduced serum IL-2 concentrations observed during aging can be used as a biological immunodeficiency marker. The results obtained did not show any significant differences between the study groups, even if mean values were slightly decreased in the elderly group, as compared to the adult one. This finding does not justify the age-dependent deficiency of the immune response, i.e., to explain this condition, one needs another pathogenetic hypothesis. It is suggested that one such hypothesis could be the alteration of IL-2 receptors which undergo major cleavage and minor re-expression in the elderly, causing this way some receptorial changes with consequent reduction of T-helper activation.

10.
Arch Gerontol Geriatr ; 9(2): 163-80, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2589917

RESUMO

This study reports two groups of elderly diabetic patients and normal subjects, with or without hypercholesterolemia and hypertriglyceridemia, who presented a decrease of the T lymphocyte-mediated function, proliferative capacity, phagocytosis, cytotoxicity and surface markers. This fall was more evident in hypercholesterolemic and hypertriglyceridemic subjects. The humoral responses and other parameters studied did not reveal significant variations. The authors also observed that recombinant interleukin-2 (rIL-2) stimulation determined a satisfactory response in healthy and diabetic subjects, while it did not normalize values in patients with altered lipid balance.


Assuntos
Diabetes Mellitus/imunologia , Sistema Imunitário/efeitos dos fármacos , Interleucina-2/farmacologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Hipercolesterolemia/imunologia , Hipertrigliceridemia/imunologia , Sistema Imunitário/fisiopatologia , Proteínas Recombinantes/farmacologia
11.
Arch Gerontol Geriatr ; 11(2): 133-9, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-15374484

RESUMO

The authors analyzed the expression of some genes involved in the control of T lymphocyte proliferation in a group of healthy elderly subjects. They focused their attention on genes involved in the G(0)/G(1) transition (TK, PCNA, H3, IL2-R) and showed decreased expression in the TK, H3 and IL2-R genes. Using flow cytofluorimetry, delayed transition from the G(0)/G(1) to the S stage was observed.

12.
Artigo em Inglês | MEDLINE | ID: mdl-10760731

RESUMO

OBJECTIVE: The hyaluronate receptor CD44 is a cell surface protein that is involved in several functions. To elucidate whether CD44 plays a role in periapical lesions, an immunohistochemical technique was used to study its distribution. STUDY DESIGN: Twenty periapical lesions-16 periapical granulomas and 4 radicular cysts-constituted the sample. Formalin-fixed/paraffin-embedded tissue sections were studied by means of immunohistochemistry for the presence of the standard CD44H form and its V3 splicing variant. RESULTS: Immunohistochemical staining for CD44H and CD44V3 was observed on epithelial, endothelial, and connective tissue cells. The cells of the fibrous lining around each granuloma were positive, showing an immune reactive pattern directly correlated with the dimension of the lesion. Epithelial rests of Malassez were strongly positive; the reaction product was also evident in the epithelial lining of the cysts. Blood vessels, mainly observed around the lesion, were immunoreactive for CD44. CONCLUSIONS: Our findings demonstrate that CD44H and its V3 variant are expressed in at least 3 different tissue types of periapical lesions. These glycoproteins may be involved in different steps of periapical lesion pathogenesis and evolution.


Assuntos
Receptores de Hialuronatos/metabolismo , Tecido Periapical/metabolismo , Doença Crônica , Células Epiteliais/metabolismo , Humanos , Imuno-Histoquímica , Granuloma Periapical/metabolismo , Ligamento Periodontal/metabolismo , Cisto Radicular/metabolismo , Coloração e Rotulagem/métodos
13.
Chir Ital ; 31(6): 1297-1313, 1979 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-233422

RESUMO

It is by now an established fact that the status of the immune system stands in some relationship with the onset and evolution of malignancy. To clarify this relationship the authors investigated the immune system of patients with pulmonary carcinoma, with special regard to the functions of the T and B lymphocyte lines. After suitable explanation of their experimental protocol, which involved immunological monitoring and the study of relationships between immunological changes and the extent and histological type of malignancy, and also the effects of any treatments being administered, the authors describe the results obtained in 18 preoperative patients. The study revealed an overall diminution of cell-mediated immune activity: less strongly positive DNCB skin tests, reduced capacity for making E rosettes, reduced blast transformation with PHA. With B lymphocytes the EA rosette test was often depressed, whereas antibody titers were normal or even above normal, and the pokeweed blast test was invariable above normal values. These preliminary results show that at the time of diagnosing malignancy, the greater aggressiveness characteristic of the less differentiated cellular types, or of stages of diffuse malignancy, is associated with overpowering of cell defenses and (within certain limits) enhancement of the humoral response.


Assuntos
Adenocarcinoma Bronquioloalveolar/imunologia , Carcinoma de Células Pequenas/imunologia , Carcinoma de Células Escamosas/imunologia , Neoplasias Pulmonares/imunologia , Antígenos de Neoplasias/análise , Linfócitos B/imunologia , Antígeno Carcinoembrionário/análise , Dinitroclorobenzeno , Humanos , Lectinas/farmacologia , Ativação Linfocitária , Formação de Roseta , Testes Cutâneos , Linfócitos T/imunologia
14.
Acta Otorhinolaryngol Ital ; 14(6): 611-25, 1994.
Artigo em Italiano | MEDLINE | ID: mdl-7740961

RESUMO

Patients with H&N tumours treated with surgery, chemo- and radiotherapy also underwent an immunologic therapy with timopentina to evaluate clinic and immunologic efficacy during a 1-year follow-up. Twenty-five patients were recorded in this study divided at random into two groups. In group A the patients were administered timopentina (50 mg/3 times per week/6 weeks) subcutaneously in 4 o 5 cycles during the year. Group B were not administered timopentina. The immunologic state was assessed through investigation of the following: Evaluation of PBL and their T and B cell subpopulations Phagocytosis and blastigenesis Surface receptor and soluble receptor of IL2 NK activity IL1 production. The immunologic values of the two groups were correlated against a control group of twenty non-neoplastic patients. Our study revealed a better immunologic conditions at the end of follow-up in patients treated with timopentina compared to the other patients.


Assuntos
Imunoterapia , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirurgia , Neoplasias Laríngeas/terapia , Laringe/efeitos dos fármacos , Laringe/efeitos da radiação , Laringe/cirurgia , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/cirurgia , Neoplasias Nasofaríngeas/terapia , Nasofaringe/efeitos dos fármacos , Nasofaringe/efeitos da radiação , Nasofaringe/cirurgia , Neoplasias Orofaríngeas/radioterapia , Neoplasias Orofaríngeas/cirurgia , Neoplasias Orofaríngeas/terapia , Orofaringe/efeitos dos fármacos , Orofaringe/efeitos da radiação , Orofaringe/cirurgia , Timopentina/farmacologia , Timopentina/uso terapêutico , Terapia Combinada , Seguimentos , Humanos , Interleucina-2/biossíntese , Interleucina-2/metabolismo , Células Matadoras Naturais/metabolismo , Ativação Linfocitária , Fagocitose , Linfócitos T
15.
Minerva Stomatol ; 44(5): 205-9, 1995 May.
Artigo em Italiano | MEDLINE | ID: mdl-7476773

RESUMO

Often teeth are the only items which can be used for personal identification in forensic medicine. In the present work we describe a method to extract and amplify DNA from dental elements ranging from 2 weeks to 5 year from the avulsion. PCR (polymerase chain reaction) was used to amplify VNTR sequences; the alleles products were electrophoresed, visualized by traditional methods and compared to the amplified products obtained from the matching blood sample. Our results give a new and powerful investigative tool for personal identification in the field of forensic odontostomatology, since such a procedure can be successfully applied both to recent and to ancient teeth.


Assuntos
DNA/genética , Polimorfismo Genético , Dente/química , Apolipoproteínas B/genética , DNA/análise , DNA/isolamento & purificação , Eletroforese em Gel de Ágar , Eletroforese em Gel de Poliacrilamida , Odontologia Legal , Humanos , Repetições Minissatélites , Reação em Cadeia da Polimerase/métodos
16.
Minerva Stomatol ; 48(11): 495-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10768008

RESUMO

BACKGROUND: Clinical epidemiologic studies carried out in smokers versus non smokers support the concept that tobacco-related factor may affect the periodontal tissues and wound healing. METHODS: In this study, the role of nicotine on the integrin alpha 2 chain immunocytochemical expression, in human gingival fibroblasts (HGF) was investigated in vitro. The kinetic induction of this type of integrin on HGF in response to increasing percentage of nicotine was been characterized. A human gingival fibroblast strain, derived from a healthy individual with non-inflamed gingiva, was used in this study. The cells were then grown on acetylated microscope slides and fixed with cold ethanol, samples were then incubated for 16 to 19 hrs at 4 degrees C to anti-human alpha 2 integrin chain monoclonal antibody. RESULTS: In control cultures and in HGF treated with 0.025 microM nicotine the initial higher expression of alpha 2 chain decreased (grade 1 in both culture) while in HGF treated with 0.075 microM increased (grade 3). After 48 hours HGF exposed to 0.075 microM nicotine, increased further their expression of alpha 2 chain. CONCLUSIONS: The results obtained demonstrate a dose-time dependent nicotine influence on immunocytochemical expression of alpha 2 integrin chain. These data suggest that nicotine may promote a collagene breakdown via an increase of alpha 2 integrin chain expression.


Assuntos
Fibroblastos/efeitos dos fármacos , Gengiva/efeitos dos fármacos , Integrinas/análise , Nicotina/efeitos adversos , Fumar/efeitos adversos , Células Cultivadas , Gengiva/metabolismo , Humanos , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Fatores de Tempo
17.
Leukemia ; 25(7): 1080-94, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21494257

RESUMO

The Ras/Raf/mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway is often implicated in sensitivity and resistance to leukemia therapy. Dysregulated signaling through the Ras/Raf/MEK/ERK pathway is often the result of genetic alterations in critical components in this pathway as well as mutations at upstream growth factor receptors. Unrestricted leukemia proliferation and decreased sensitivity to apoptotic-inducing agents and chemoresistance are typically associated with activation of pro-survival pathways. Mutations in this pathway and upstream signaling molecules can alter sensitivity to small molecule inhibitors targeting components of this cascade as well as to inhibitors targeting other key pathways (for example, phosphatidylinositol 3 kinase (PI3K)/phosphatase and tensin homologue deleted on chromosome 10 (PTEN)/Akt/mammalian target of rapamycin (mTOR)) activated in leukemia. Similarly, PI3K mutations can result in resistance to inhibitors targeting the Ras/Raf/MEK/ERK pathway, indicating important interaction points between the pathways (cross-talk). Furthermore, the Ras/Raf/MEK/ERK pathway can be activated by chemotherapeutic drugs commonly used in leukemia therapy. This review discusses the mechanisms by which abnormal expression of the Ras/Raf/MEK/ERK pathway can contribute to drug resistance as well as resistance to targeted leukemia therapy. Controlling the expression of this pathway could improve leukemia therapy and ameliorate human health.


Assuntos
Antineoplásicos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Leucemia/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/fisiologia , Terapia de Alvo Molecular , Proteínas de Neoplasias/fisiologia , Quinases raf/fisiologia , Proteínas ras/fisiologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Modelos Biológicos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/fisiologia , Inibidores de Fosfoinositídeo-3 Quinase , Quinases raf/antagonistas & inibidores , Quinases raf/genética , Proteínas ras/antagonistas & inibidores , Proteínas ras/genética
18.
Leukemia ; 25(7): 1064-79, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21436840

RESUMO

It has become apparent that regulation of protein translation is an important determinant in controlling cell growth and leukemic transformation. The phosphoinositide 3-kinase (PI3K)/phosphatase and tensin homologue deleted on chromosome ten (PTEN)/Akt/mammalian target of rapamycin (mTOR) pathway is often implicated in sensitivity and resistance to therapy. Dysregulated signaling through the PI3K/PTEN/Akt/mTOR pathway is often the result of genetic alterations in critical components in this pathway as well as mutations at upstream growth factor receptors. Furthermore, this pathway is activated by autocrine transformation mechanisms. PTEN is a critical tumor suppressor gene and its dysregulation results in the activation of Akt. PTEN is often mutated, silenced and is often haploinsufficient. The mTOR complex1 (mTORC1) regulates the assembly of the eukaryotic initiation factor4F complex, which is critical for the translation of mRNAs that are important for cell growth, prevention of apoptosis and transformation. These mRNAs have long 5'-untranslated regions that are G+C rich, rendering them difficult to translate. Elevated mTORC1 activity promotes the translation of these mRNAs via the phosphorylation of 4E-BP1. mTORC1 is a target of rapamycin and novel active-site inhibitors that directly target the TOR kinase activity. Although rapamycin and novel rapalogs are usually cytostatic and not cytotoxic for leukemic cells, novel inhibitors that target the kinase activities of PI3K and mTOR may prove more effective for leukemia therapy.


Assuntos
Antineoplásicos/farmacologia , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia/tratamento farmacológico , Terapia de Alvo Molecular , Proteínas de Neoplasias/fisiologia , PTEN Fosfo-Hidrolase/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/fisiologia , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/fisiologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Leucêmica da Expressão Gênica/genética , Humanos , Leucemia/genética , Alvo Mecanístico do Complexo 1 de Rapamicina , MicroRNAs/genética , Complexos Multiproteicos/antagonistas & inibidores , Complexos Multiproteicos/efeitos dos fármacos , Complexos Multiproteicos/fisiologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , PTEN Fosfo-Hidrolase/antagonistas & inibidores , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/genética , Inibidores de Fosfoinositídeo-3 Quinase , Fosforilação/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas/antagonistas & inibidores , Proteínas/efeitos dos fármacos , Proteínas/fisiologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Pseudogenes , RNA Mensageiro/genética , RNA Neoplásico/genética , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/genética , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/efeitos dos fármacos , Fatores de Transcrição/fisiologia
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