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1.
Arch Dermatol Res ; 314(5): 417-425, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34047823

RESUMO

BACKGROUND: Stromal vascular fraction (SVF), derived enzymatically or mechanically from adipose tissue, contains a heterogenous population of cells and stroma, including multipotent stem cells. The regenerative capacity of SVF may potentially be adapted for a broad range of clinical applications, including the healing of acute cutaneous wounds. OBJECTIVE: To evaluate the available literature on the efficacy and safety of autologous adipose-derived stromal vascular fraction (SVF) for the treatment of acute cutaneous wounds in humans. METHODS: A systematic review of the literature utilizing MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials was performed to identify published clinical trials of autologous adipose-derived SVF or similar ADSC-containing derivatives for patients with acute cutaneous wounds. This was supplemented by searches for ongoing clinical trials through ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform. RESULTS: 872 records were initially retrieved. Application of inclusion and exclusion criteria yielded 10 relevant studies: two completed non-randomized controlled trials and eight ongoing clinical trials. Both completed studies reported a statistically significant benefit in percentage re-epithelialization and time to healing for the SVF treatment arms. Safety information for SVF was not provided. Ongoing clinical trials were assessing outcomes such as safety, patient and observer reported scar appearance, wound healing rate, and wound epithelization. CONCLUSION: In the context of substantial limitations in the quantity and quality of available evidence, the existing literature suggests that SVF may be a useful treatment for acute cutaneous wounds in humans. More clinical trials with improved outcome measures and safety assessment are needed.


Assuntos
Tecido Adiposo , Fração Vascular Estromal , Cicatriz , Humanos , Reepitelização , Cicatrização
2.
Psychol Med ; 46(11): 2435-44, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27305830

RESUMO

BACKGROUND: Relapse is distressingly common after the first episode of psychosis, yet it is poorly understood and difficult to predict. Investigating changes in cognitive function preceding relapse may provide new insights into the underlying mechanism of relapse in psychosis. We hypothesized that relapse in fully remitted first-episode psychosis patients was preceded by working memory deterioration. METHOD: Visual memory and verbal working memory were monitored prospectively in a 1-year randomized controlled trial of remitted first-episode psychosis patients assigned to medication continuation (quetiapine 400 mg/day) or discontinuation (placebo). Relapse (recurrence of positive symptoms of psychosis), visual (Visual Patterns Test) and verbal (Letter-Number span test) working memory and stressful life events were assessed monthly. RESULTS: Remitted first-episode patients (n = 102) participated in the study. Relapsers (n = 53) and non-relapsers (n = 49) had similar baseline demographic and clinical profiles. Logistic regression analyses indicated relapse was associated with visual working memory deterioration 2 months before relapse [odds ratio (OR) 3.07, 95% confidence interval (CI) 1.19-7.92, P = 0.02], more stressful life events 1 month before relapse (OR 2.11, 95% CI 1.20-3.72, P = 0.01) and medication discontinuation (OR 5.52, 95% CI 2.08-14.62, P = 0.001). CONCLUSIONS: Visual working memory deterioration beginning 2 months before relapse in remitted first-episode psychosis patients (not baseline predictor) may reflect early brain dysfunction that heralds a psychotic relapse. The deterioration was found to be unrelated to a worsening of psychotic symptoms preceding relapse. Testable predictors offer insight into the brain processes underlying relapse in psychosis.


Assuntos
Antipsicóticos/farmacologia , Disfunção Cognitiva/fisiopatologia , Progressão da Doença , Memória de Curto Prazo/fisiologia , Transtornos Psicóticos/fisiopatologia , Estresse Psicológico/fisiopatologia , Adulto , Antipsicóticos/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Masculino , Prognóstico , Transtornos Psicóticos/tratamento farmacológico , Fumarato de Quetiapina/administração & dosagem , Fumarato de Quetiapina/farmacologia , Recidiva , Indução de Remissão , Fatores de Tempo , Adulto Jovem
3.
Cell Mol Biol (Noisy-le-grand) ; 62(4): 123-9, 2016 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-27188746

RESUMO

Medulloblastoma is the most common type of malignant brain tumor in children. Despite a relatively high long-term survival rate, complications still represent great burden for the majority of patients receiving traditional therapy. Therefore, the development of new effective treatments and drugs is urgently needed. A cell counting kit-8 (CCK-8) and colony formation assay were used to evaluate medulloblastoma cell proliferation and colony formation, respectively. Cell cycles and apoptosis were assessed by flow cytometry. A western blot was performed to determine the levels of protein expression. Axenograft model of medulloblastoma was established to evaluate the in vivo anticancer effects of icariin. The CCK-8 assay showed that icariin decreased cell viability in a dose- and time-dependent manner. The colony formation assay indicated that icariin potently inhibited the colony formation ability of Daoy and D341 cells. Icariin-induced proliferation inhibition may be due to S-phase arrest in medulloblastoma cells. In addition, icariin induced apoptosis in a dose-dependent manner, as shown by the results of annexin V/propidium iodide (PI) double staining and Hoechst 33342 staining. Icariin progressively inhibited tumor growth and induced apoptosis in a mouse model. Moreover, cell cycle regulators Cyclin A, CDK2, and Cyclin B1, and apoptosis-related proteins caspase-3, caspase-9, poly (ADP-ribose) polymerase (PARP), and Bcl-2 were modulated in response to treatment with icariin in vitro and in vivo. Our results suggest that icariin may exert anticancer effects. Thus, it is a promising drug for medulloblastoma treatment.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias Cerebelares/patologia , Flavonoides/farmacologia , Meduloblastoma/patologia , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fatores de Tempo , Ensaio Tumoral de Célula-Tronco , Ensaios Antitumorais Modelo de Xenoenxerto
4.
J Clin Pharm Ther ; 34(4): 407-14, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19583673

RESUMO

OBJECTIVE: The study aimed to investigate the clinical impact of pharmacist-physician co-managed programme on the management of hyperlipidaemia. METHODS: The study was a prospective randomized controlled trial. Adult patients were selected if: (i) they were taking one or more lipid-lowering agents with a valid lipid panel before their next follow up; (ii) had a baseline lipid profile within the previous 6 months; (iii) their lipid panel did not reach the targeted low-density lipoprotein-cholesterol (LDL-C) goal based on the National Cholesterol Education Programme Adult Treatment Panel III. Pharmacists interviewed patients in the intervention group for 15-30 min to provide consultation on the drug regimen and lifestyle modifications. A telephone follow-up every 4 weeks and a follow-up interview on the date of the physician visit were scheduled. Patients in the control group received routine conventional care. The primary outcome measurement was the change in lipid panel between baseline and at the end of study. RESULTS: One hundred and eighteen patients were recruited to the study [58 patients in intervention group (mean age 63 +/- 10 years old) and 60 in control group (mean age 61 +/- 12 years old)]. Starting with similar baseline levels, the end of study LDL-C and total cholesterol levels for the intervention and control groups were LDL-C: 2.80 +/- 0.89 mmol/L and total cholesterol 4.75 +/- 1.08 mmol/L vs. LDL-C: 3.24 +/- 0.78 mmol/L and total cholesterol 5.18 +/- 0.93 mmol/L, respectively. The differences were statistically significant (P < 0.0015). CONCLUSION: The study showed that a pharmacist-physician co-managed programme for hyperlipidaemic patient was effective in getting more patients to reach their target lipid levels.


Assuntos
Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/uso terapêutico , Farmacêuticos/organização & administração , Médicos/organização & administração , Idoso , Colesterol/sangue , LDL-Colesterol/sangue , LDL-Colesterol/efeitos dos fármacos , Feminino , Seguimentos , Hong Kong , Humanos , Relações Interprofissionais , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Assistência Farmacêutica/organização & administração , Papel Profissional , Estudos Prospectivos , Método Simples-Cego
5.
J Endocrinol ; 173(3): 493-506, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12065239

RESUMO

A prolactin (PRL)-responsive 3'-end cDNA encoding rat alpha4 phosphoprotein was previously isolated from a rat lymphoma cDNA library. Rat alpha4 is a homologue of yeast Tap42 and is a component of the mammalian target-of-rapamycin (mTOR) signalling pathway that stimulates translation initiation and G1 progression in response to nutrients and growth factors. In the present study, the full-length rat alpha4 cDNA was obtained by 5'-RACE and the 1023 bp open reading frame predicted a 340 amino acid protein of 39.1 kDa. The alpha4 mRNA was expressed in quiescent PRL-dependent Nb2 lymphoma cells deprived of PRL for up to 72 h but expression was downregulated within 4 h of PRL treatment. In contrast, PRL-independent Nb2-Sp cells showed constitutive expression of alpha4 that was not affected by PRL. Western analysis of Nb2 cell lysates or of V5-tagged-alpha4 expressed in COS-1 cells detected a single immunoreactive band of approximately 45 kDa. Enzymatic deglycosylation of affinity-purified 45 kDa alpha4 yielded the predicted 39 kDa protein. Phosphorylation of Nb2 alpha4 was induced by PRL or 2-O-tetradecanoyl-phorbol-13-acetate (TPA) and further enhanced by a combination of PRL and TPA. The Nb2 alpha4 associated with the catalytic subunit of protein phosphatase 2A and localized predominantly in Nb2 nuclear fractions with trace amounts in the cytosol. The immunosuppressant drug rapamycin inhibited proliferation of Nb2 cells in response to PRL or interleukin-2, but had no effect on Nb2-Sp cells. Furthermore, transient overexpression of alpha4 in COS-1 cells inhibited PRL stimulation of the immediate-early gene interferon regulatory factor-1 promoter activity. Therefore, PRL downregulation of alpha4 expression and/or PRL-inducible phosphorylation of alpha4 may be necessary for PRL receptor (PRLr) signalling to the interferon regulatory factor-1 promoter in the Nb2 cells and, furthermore, implicates cross-talk between the mTOR and PRLr signalling cascades during Nb2 cell mitogenesis.


Assuntos
Imunossupressores/farmacologia , Fosfoproteínas/genética , RNA Mensageiro/análise , Receptores da Prolactina/metabolismo , Transdução de Sinais , Sirolimo/farmacologia , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Animais , Células COS , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Chaperonas Moleculares , Dados de Sequência Molecular , Fosfoproteínas/análise , Fosforilação , Prolactina/farmacologia , Ratos , Alinhamento de Sequência , Acetato de Tetradecanoilforbol/farmacologia , Células Tumorais Cultivadas
6.
Mol Cell Endocrinol ; 176(1-2): 57-65, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11369443

RESUMO

Leptin was originally believed to be an exclusively adipocyte-derived hormone regulating appetite and energy balance. It has recently become apparent that leptin is actively expressed in a number of other tissues including the CNS and pituitary, as well as brain- and pituitary-derived cell lines. However, the factors controlling leptin expression in cells of neuroectodermal origin are unknown. The mouse leptin gene 5'-flanking DNA contains multiple AP-1 and SRF-1 binding sites as well as a consensus CRE site at -491 to -482 bp. In addition, a number of potential PIT1 and Oct-1 binding sites may contribute to leptin gene transcription in pituitary and brain. We have used leptin promoter-luciferase reporter constructs to examine the regulation of the leptin promoter in 3T3-L1 preadipocytes, C6 glioma cells, and GH3 pituitary cells in response to serum and hormonal stimuli. Cells were transiently transfected with reporter constructs containing either the proximal 500 bp of the leptin promoter (-500-luc) or 6000 bp of the leptin gene 5' flanking region (-6000-luc). Functional analysis indicates that the leptin promoter is constitutively active in all 3 cell lines. Transcriptional activity was significantly higher with a -500 to +9 promoter than with a construct containing -6000 to +9 bp of 5' flanking DNA, indicating the presence of repressor elements which may contribute to the tissue-specific regulation of leptin expression. However, qualitatively similar results were observed with both constructs in response to serum and hormonal manipulation. Leptin promoter activity was significantly stimulated by serum in all cell lines, although to varying extents. In contrast, the response of the leptin promoter to insulin, IGF-1 and dibutyryl cAMP was cell-type specific and dependent on the presence or absence of FBS in the culture medium. Insulin, IGF-1 and dibutyryl cAMP each caused an approximately two-fold stimulation of leptin promoter activity in 3T3-L1 cells under serum-free conditions, but had no significant effect in the presence of 10% FBS. In contrast, dibutyryl cAMP markedly stimulated leptin promoter activity (5-8-fold) in C6 or GH3 cells in the presence or absence of FBS, whereas insulin or IGF-1 had minimal effects. These findings support our previous studies on the regulation of leptin steady state mRNA levels in C6 cells and demonstrate tissue-specific differences in the regulation of leptin gene transcription in adipose vs. neuroectodermal tissues.


Assuntos
Regulação da Expressão Gênica , Leptina/genética , Regiões Promotoras Genéticas/genética , Transcrição Gênica , Células 3T3 , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Sequência de Bases , Diferenciação Celular , Linhagem Celular , AMP Cíclico/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Reporter/genética , Glioma/metabolismo , Insulina/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Dados de Sequência Molecular , Mutação/genética , Hipófise/citologia , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Ratos , Transcrição Gênica/efeitos dos fármacos , Células Tumorais Cultivadas
7.
Mol Endocrinol ; 15(4): 589-99, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11266510

RESUMO

Basic fibroblast growth factor (bFGF; FGF-2) is one of 19 related members of a growth factor family with mitogenic and hormone-regulatory functions. In Xenopus laevis oocytes, a 1.5-kb FGF-2 antisense (GFG) RNA complementary to the third exon and 3'-untranslated region (UTR) of FGF-2 mRNA has been implicated in FGF-2 mRNA editing and stability. The human homolog has been cloned, and we localized this gene by yeast artificial chromosome (YAC), somatic cell, and radiation hybrid panels to the same chromosomal site as FGF-2 (chromosome 4, JO4513 adjacent to D4S430), confirming this as a human endogenous antisense gene. The full-length GFG antisense RNA encodes a 35-kDa protein, which is highly homologous with the MutT family of antimutator nucleosidetriphosphatases (NTPases). We show that human pituitary tumors express FGF-2 and its endogenous antisense partner GFG. While normal pituitary expresses GFG but not FGF-2, pituitary adenomas express FGF-2 and have reduced levels of GFG; aggressive and recurrent adenomas expressed more FGF than GFG mRNA. To examine the effects of this antisense gene in the pituitary, we transfected the pituitary-derived GH4 mammosomatotroph cell line with constructs encoding the full-length human GFG cDNA. Transiently and stably transfected cells expressed the 35-kDa GFG protein that was localized to the cytoplasm. These cells exhibited enhanced PRL expression as documented by transiently transfected PRL-luciferase reporter assay and by endogenous PRL protein. GFG expression in these cells did not alter endogenous FGF-2 expression but increased the proportion of the higher molecular mass 22-kDa form of GH. Moreover, GFG expression inhibited cell proliferation as shown by [(3)H]thymidine incorporation, proliferating cell nuclear antigen (PCNA) nuclear staining, and cell cycle analysis. We conclude that the GFG-encoded protein has divergent hormone-regulatory and antiproliferative actions in the pituitary that are independent of FGF-2 expression. GFG represents a novel mechanism involved in restraining pituitary tumor cell growth while promoting hormonal activity.


Assuntos
Cromossomos Humanos Par 4 , Fatores de Crescimento de Fibroblastos , Hipófise/citologia , Hipófise/fisiologia , Prolactina/biossíntese , Proteínas/genética , Adenoma/genética , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Citoplasma/genética , Citoplasma/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Hormônio do Crescimento/biossíntese , Humanos , Hipófise/efeitos dos fármacos , Neoplasias Hipofisárias/genética , Biossíntese de Proteínas , Ratos , Transfecção
8.
Mol Cell Endocrinol ; 162(1-2): 69-78, 2000 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-10854699

RESUMO

The fibroblast growth factor-2 (FGF-2) gene is bidirectionally transcribed to produce the FGF-2 mRNA and a 1.5 kb antisense (FGF-AS) transcript complementary to the 3' untranslated region of the FGF-2 transcript. The FGF-AS RNA has been postulated to play a role in the post-transcriptional regulation of FGF-2, but this function has not been conclusively demonstrated. We characterized FGF-AS cDNAs from rat brain and C6 glioma cells, and investigated their role in regulation of FGF-2 expression. Three FGF-AS cDNAs were isolated; the full-length FGF-AS mRNA and two alternative splice variants lacking exon 2 or exons 2 and 3 of the FGF-AS sequence. The alternatively spliced FGF-AS RNAs are widely expressed in the CNS, whereas liver predominantly expressed the full-length transcript. The full-length and first splice variant encode 35 and 28 kDa isoforms of GFG, a MutT-related nuclear protein, whereas the second splice variant was not translated. The effect of FGF-AS RNA on FGF-2 expression was evaluated in stable C6 transfectants over-expressing the full-length or alternatively spliced FGF-AS RNA forms. All three constructs suppressed cellular FGF-2 protein (but not FGF-2 mRNA) levels, and this effect correlated directly with the level of FGF-AS RNA. Cellular FGF receptor content was increased and cell proliferation inhibited compared to wild type or vector-transfected cells, indicating disruption of the FGF-2 autocrine pathway by FGF-AS RNA. These findings demonstrate for the first time that the FGF-AS RNA regulates FGF-2 expression in mammalian cells, and suggest that this effect is exerted predominantly at the level of translation.


Assuntos
Sistema Nervoso Central/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , RNA Antissenso/genética , RNA Antissenso/metabolismo , Processamento Alternativo , Animais , Sequência de Bases , Encéfalo/metabolismo , Divisão Celular , Primers do DNA/genética , DNA Complementar/genética , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Dados de Sequência Molecular , Biossíntese de Proteínas , Ratos , Distribuição Tecidual , Células Tumorais Cultivadas
9.
J Clin Endocrinol Metab ; 85(4): 1641-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10770210

RESUMO

Serum autoantibodies against eye muscle antigens are closely linked with thyroid-associated ophthalmopathy (TAO), although their significance is unclear. The two antigens that are most often recognized are eye muscle membrane proteins with molecular masses of 55 and 64 kDa, as determined from immunoblotting with crude human or porcine eye muscle membranes. We cloned a fragment of the 55-kDa protein by screening an eye muscle expression library with affinity-purified anti-55 kDa protein antibody prepared from a TAO patient's serum. A complementary DNA (cDNA) encoding a novel protein, which we have called G2s, was sequenced on both strands, and its size was 411 bp. The open reading frame of G2s corresponded to a 121-amino acid peptide with a size of 1.4 kb. Using the rapid amplification of 5'-cDNA ends technique we were able to clone an additional 0.3 kb of the protein. G2s did not share significant homologies with any other entered protein in computer databases and had one putative transmembrane domain. Using the 1.4 kb cDNA as probe in Northern blotting of a panel of messenger ribonucleic acids prepared from human tissues, the parent protein was shown to correspond to a large molecule of about 5.8 kb with a calculated molecular mass of approximately 220 kDa, consistent with earlier immunoblot studies performed in the absence of reducing agents. G2s was strongly expressed in eye muscle, thyroid, and other skeletal muscle and to a lesser extent in pancreas, liver, lung, and heart muscle, but not in kidney or orbital fibroblasts. We tested sera from patients with Graves' hyperthyroidism with and without ophthalmopathy and from control patients and subjects for antibodies against a G2s fusion protein by immunoblotting and enzyme-linked immunosorbent assay. In immunoblotting, antibodies reactive with G2s were identified in 70% of patients with TAO of less than 3 yr duration, 53% with TAO of more than 3 yr duration, 36% with Graves' hyperthyroidism without evident ophthalmopathy, 17% with Hashimoto's thyroiditis, 3% with type 1 diabetes, 23% with nonimmunological thyroid disorders, and 16% of normal subjects. The prevalences, compared to normal values, were significant for the two groups of patients with TAO, but not for the other groups. Tests were positive in 54% of patients with active TAO, 33% with chronic ophthalmopathy, 36% with Graves' hyperthyroidism, 54% with Hashimoto's thyroiditis, 23% with type 1 diabetes, and in 11% of normal subjects using enzyme-linked immunosorbent assay. The antibodies predicted the development of the ocular myopathy subtype of TAO in six of seven patients and the congestive ophthalmopathy subtype in seven of eight patients, respectively, with Graves' hyperthyroidism studied prospectively during and after antithyroid drug therapy. Antibodies reactive with G2s may be early markers of ophthalmopathy in patients with Graves' hyperthyroidism. Because G2s is expressed in both thyroid and eye muscle, immunoreactivity against a shared epitope in the two tissues may explain the well known link between thyroid autoimmunity and ophthalmopathy.


Assuntos
Autoanticorpos/imunologia , Proteínas do Olho , Doença de Graves/imunologia , Proteínas de Membrana/imunologia , Músculos Oculomotores/química , Glândula Tireoide/química , Adulto , Sequência de Aminoácidos , Autoanticorpos/sangue , Western Blotting , Clonagem Molecular , Diabetes Mellitus Tipo 1/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Proteínas de Membrana/química , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Dados de Sequência Molecular , RNA Mensageiro/análise , Tireoidite Autoimune/imunologia
10.
Mol Cell Endocrinol ; 170(1-2): 233-42, 2000 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-11162906

RESUMO

The fibroblast growth factor-2 (FGF-2) gene is bidirectionally transcribed to produce the FGF-2 mRNA and a 1.5 kb antisense (FGF-AS) transcript complementary to the 3' untranslated region of the FGF-2 transcript. The FGF-AS RNA has been postulated to play a role in the post-transcriptional regulation of FGF-2, but this function has not been conclusively demonstrated. We characterized FGF-AS cDNAs from rat brain and C6 glioma cells, and investigated their role in regulation of FGF-2 expression. Three FGF-AS cDNAs were isolated; the full-length FGF-AS mRNA and two alternative splice variants lacking exon 2 or exons 2 and 3 of the FGF-AS sequence. The alternatively spliced FGF-AS RNAs are widely expressed in the CNS, whereas liver predominantly expressed the full-length transcript. The full-length and first splice variant encode 35 and 28 kDa isoforms of GFG, a MutT-related nuclear protein, whereas the second splice variant was not translated. The effect of FGF-AS RNA on FGF-2 expression was evaluated in stable C6 transfectants over-expressing the full-length or alternatively spliced FGF-AS RNA forms. All three constructs suppressed cellular FGF-2 protein (but not FGF-2 mRNA) levels, and this effect correlated directly with the level of FGF-AS RNA. Cellular FGF receptor content was increased and cell proliferation inhibited compared to wild type or vector-transfected cells, indicating disruption of the FGF-2 autocrine pathway by FGF-AS RNA. These findings demonstrate for the first time that the FGF-AS RNA regulates FGF-2 expression in mammalian cells, and suggest that this effect is exerted predominantly at the level of translation.


Assuntos
Processamento Alternativo , Sistema Nervoso Central/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , RNA Antissenso/genética , RNA Antissenso/metabolismo , Animais , Sequência de Bases , Encéfalo/metabolismo , Divisão Celular , Primers do DNA/genética , DNA Complementar/genética , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Dados de Sequência Molecular , Biossíntese de Proteínas , Ratos , Distribuição Tecidual , Células Tumorais Cultivadas
11.
Crit Rev Clin Lab Sci ; 37(6): 523-49, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11192331

RESUMO

Thyroid-associated ophthalmopathy (TAO) is a progressive eye disorder characterized by immune-mediated inflammation of the extraocular muscles and orbital connective tissue. TAO is linked, in a unique way, with thyroid autoimmunity, in particular Graves' hyperthyroidism. Our working hypothesis for the pathogenesis of TAO is that recognition of a thyrotropin receptor (TSHR)-like protein in the orbital preadipocytes by antibodies may be the initial event leading to homing of lymphocytes into the orbital tissues. In the course of thyroid inflammation, antibodies and T cells reactive against G2s expressed in thyroid membranes cross-react with the protein in the eye muscle fiber, leading to eye muscle damage and dysfunction. Those patients with anti-G2s antibodies develop ocular myopathy. Antibodies against flavoprotein, the 64-kDa protein, which are produced in the context of eye muscle fiber damage and mitochondrial rupture, are sensitive markers of immune-mediated fiber necrosis in patients with ophthalmopathy but do not directly damage the eye muscle. Antibodies against type XIII collagen, which is localized in the plasma membranes of orbital fibroblast, may be a new marker for the congestive ophthalmopathy subtype of TAO. The measurement of antibodies against key eye muscle and orbital connective tissue autoantigens may have a role in the management of active ophthalmopathy and its prediction in patients with Graves' hyperthyroidism.


Assuntos
Doença de Graves/patologia , Doença de Graves/terapia , Animais , Doença de Graves/imunologia , Doença de Graves/metabolismo , Humanos
12.
Mol Cell Endocrinol ; 137(2): 187-95, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9605521

RESUMO

The rat Nb2-11C lymphoma cell line expresses high affinity prolactin (PRL) receptors, and requires lactogenic hormones for survival and proliferation. We have applied differential display to identify genes which are differentially induced in Nb2-11C cells following PRL stimulation, or which are constitutively expressed in the PRL-independent Nb2-Sp cells. In the present study we characterized a clone (22c.2) which was expressed in Nb2-Sp cells, and in Nb2-11C cells given PRL for 3 h but not in untreated cells. The 279 bp cDNA had 95% homology with the 3' end of the murine 2.6 kb FGF-inducible gene 14 (FIN14). When clone 22c.2 was used to screen a Nb2-Sp cDNA library to obtain a longer cDNA, a unique 1039 bp clone PNR (Prolactin-responsive/ NonO-Related) was isolated, subcloned and sequenced. The deduced amino acid sequence encoded by the PNR open reading frame had significant homology with a family of RNA- and DNA-binding proteins which include the human polypyrimidine tract-binding protein (PTB)-associated splicing factor (PSF), the murine non-POU-domain-containing octamer-binding protein (NonO) and the human NonO homologue p54nrb. Nb2-11C cells expressed three PNR-related mRNA transcripts of 2.5, 3.0 and > 10 kb. Expression of the 2.5 and 3.0 kb transcripts were increased at least 4-fold within 3 h of PRL treatment. PNR expression was also significantly stimulated within 3 h by addition of FGF-2 to either Nb2-11C or Nb2-Sp cells, although alone FGF-2 was not mitogenic for either cell line. Reverse transcription-polymerase chain reaction (RT-PCR) confirmed the expression of both FGF-2 and FGF receptor mRNA in Nb2 cells. raising the possibility of an autocrine or paracrine function for FGF-2 in lymphoma cells. Furthermore, PRL rapidly stimulated the expression of FGF-2 mRNA in a time- and dose-dependent manner in both Nb2-11C and Nb2-Sp cells. FGF-2 expression was increased within 1 h and was maintained at a high level for at least 10 h following treatment with 2 ng/ml PRL. Western blotting with anti-FGF2 antisera demonstrated PRL stimulation of intracellular accumulation, but not secretion of immunoreactive FGF-2. The observation of PRL-responsive expression of FGF-2 in Nb2 cells suggests a previously unrecognized pathway for PRL action in lymphoid cells.


Assuntos
Fator 2 de Crescimento de Fibroblastos/genética , Proteínas Associadas à Matriz Nuclear , Proteínas Nucleares/genética , Prolactina/farmacologia , Proteínas de Ligação a RNA/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Primers do DNA/genética , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Proteínas de Ligação a DNA , Fator 2 de Crescimento de Fibroblastos/biossíntese , Fator 2 de Crescimento de Fibroblastos/farmacologia , Expressão Gênica/efeitos dos fármacos , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Linfoma/genética , Linfoma/metabolismo , Dados de Sequência Molecular , Fatores de Transcrição de Octâmero , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Ratos , Células Tumorais Cultivadas
13.
Mol Cell Endocrinol ; 133(2): 177-82, 1997 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-9406864

RESUMO

Bidirectional transcription of the basic fibroblast growth factor (FGF-2) gene gives rise to multiple polyadenylated sense mRNAs and a unique 1.5 kb antisense transcript (FGF-AS) which is complementary to the 3'-untranslated region of the FGF-2 mRNA. The rat FGF-AS cDNA encodes a novel 35 kDa nuclear protein (GFG) with homology to the MutT family of antimutator NTPases. Antibodies against the deduced amino acid sequence of GFG detected intense immunoreactivity in the nuclei of adult rat hepatocytes. Subcellular fractionation and Western blotting confirmed the presence of a 35 kDa immunoreactive protein in the nuclear fraction and, to a lesser extent, in the mitochondrial fractions of rat liver homogenates. Recombinant GFG suppressed the spontaneous mutation rate of MutT-deficient E. coli in a complementation assay. In-frame deletion of the 53 amino acids encompassing the MutT domain eliminated this activity, confirming the catalytic function of this region in the FGF antisense gene product. These findings demonstrate for the first time that the FGF-AS transcript encodes a functional nuclear protein with MutT-related enzymatic activity.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Escherichia coli , Fator 2 de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos , Monoéster Fosfórico Hidrolases/genética , Proteínas/genética , Proteínas/metabolismo , RNA Antissenso/genética , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/fisiologia , Núcleo Celular/química , Células Cultivadas , Escherichia coli/genética , Teste de Complementação Genética , Fígado/química , Fígado/citologia , Masculino , Mitocôndrias/química , Dados de Sequência Molecular , Mutagênese , Monoéster Fosfórico Hidrolases/fisiologia , Proteínas/análise , Pirofosfatases , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão
14.
Proc Natl Acad Sci U S A ; 94(10): 4943-7, 1997 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-9144169

RESUMO

An RNA transcribed from the antisense strand of the FGF-2 gene has been implicated in the regulation of FGF-2 mRNA stability in amphibian oocytes. We have now cloned and characterized a novel 1. 1-kb mRNA (fgf-as) from neonatal rat liver. In non-central nervous system (CNS) tissues the fgf-as RNA is abundantly expressed in a developmentally regulated manner. The FGF-AS cDNA contains a consensus polyadenylylation signal and a long open reading frame (ORF) whose deduced amino acid sequence predicts a 35-kDa protein with homology to the MutT family of nucleotide hydrolases. Western blot analysis with antibodies against the deduced peptide sequence demonstrates that the FGF-AS protein is expressed in a broad range of non-CNS tissue in the postnatal period. In the developing brain, the abundance of sense and antisense transcripts are inversely related, suggesting a role for the antisense RNA in posttranscriptional regulation of FGF-2 expression in this tissue. The FGF-AS is complementary to two widely separated regions in the long 3' untranslated region of the FGF-2 mRNA, in the vicinity of the proximal and distal polyadenylylation sites. These findings demonstrate that the FGF-2 and fgf-as RNAs are coordinately transcribed on a tissue-specific and developmentally regulated basis and suggest that interaction of the sense and antisense RNAs may result in posttranscriptional regulation of FGF-2 in some tissues.


Assuntos
Fator 2 de Crescimento de Fibroblastos/biossíntese , Fatores de Crescimento de Fibroblastos/biossíntese , RNA Antissenso/biossíntese , RNA Mensageiro/biossíntese , Envelhecimento/metabolismo , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos , Sequência de Bases , Encéfalo/metabolismo , Clonagem Molecular , Sequência Consenso , DNA Complementar/química , DNA Complementar/metabolismo , Embrião de Mamíferos , Embrião não Mamífero , Fator 2 de Crescimento de Fibroblastos/química , Fator 2 de Crescimento de Fibroblastos/isolamento & purificação , Fatores de Crescimento de Fibroblastos/química , Fatores de Crescimento de Fibroblastos/isolamento & purificação , Humanos , Immunoblotting , Rim/metabolismo , Fígado/metabolismo , Dados de Sequência Molecular , Miocárdio/metabolismo , Especificidade de Órgãos , Biossíntese de Proteínas , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Homologia de Sequência de Aminoácidos , Xenopus laevis
15.
Biochem Biophys Res Commun ; 223(1): 19-23, 1996 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-8660369

RESUMO

The basic fibroblast growth factor (FGF-2) gene is transcribed bidirectionally to yield multiple sense (coding) transcripts and a unique 1.5 kb antisense transcript which may regulate sense RNA stability. The antisense RNA also contains a long open reading frame that predicts a hypothetical protein with homology to the prokaryotic MutT antimutator proteins. However, translation of this protein has not previously been demonstrated. We employed antibodies against the conserved MutT-domain of the deduced human FGF-2 antisense protein (GFG) to demonstrate expression of an immunoreactive 24 kDa protein in liver extracts from Xenopus laevis, and two proteins of 28 and 35 kDa in rat liver. In rats, GFG protein expression detected by western blot was tissue-specific and correlated with the level of FGF-2 antisense mRNA expression. These findings demonstrate that, in addition to its possible RNA regulatory function, the FGF-2 antisense transcript is translated into a conserved MutT-related protein.


Assuntos
Proteínas de Escherichia coli , Fator 2 de Crescimento de Fibroblastos/genética , Fatores de Crescimento de Fibroblastos , Fígado/metabolismo , Biossíntese de Proteínas , RNA Antissenso/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/química , Northern Blotting , Western Blotting , Sequência Consenso , Sequência Conservada , Escherichia coli/enzimologia , Fator 2 de Crescimento de Fibroblastos/biossíntese , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta , Monoéster Fosfórico Hidrolases/química , Proteínas/química , Pirofosfatases , Ratos , Ratos Sprague-Dawley , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Xenopus laevis
16.
Mol Cell Endocrinol ; 118(1-2): 113-23, 1996 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-8735597

RESUMO

The basic fibroblast growth factor (bFGF) gene locus is transcribed into a number of mRNA transcripts including an antisense mRNA derived from the opposite DNA strand of the bFGF gene. Expression of this natural antisense RNA has been implicated in regulation of the bFGF sense mRNA expression and turnover. In the present study we examined the developmental pattern of expression of the bFGF antisense transcript in fetal and postnatal rat tissues. Northern hybridization with a strand-specific cRNA probe detected a 1.5-kb polyadenylated antisense RNA in all tissues examined except brain, in which two transcripts were detected as a doublet of approximately 1.3-1.5 kb in size. The level of antisense transcript expression was markedly tissue- and age-dependent. In the developing brain, both sense and antisense transcripts were detected by Northern hybridization, but the pattern of their expression was inversely related. The 6.0-kb bFGF sense transcript increased in an age-dependent manner from days 3-30 of postnatal development while the antisense transcript decreased to nearly undetectable levels over the same period. In embryonic (days 15-19) liver, kidney, heart and intestine bFGF antisense RNA expression was low but increased dramatically at parturition, rising 5-10-fold over fetal levels by 10 days of age, then declined slowly to a new steady-state level in adult tissues. The level of antisense RNA in these tissues was much higher than that of bFGF sense mRNA, which was undetectable by Northern analysis. Sense and antisense trancripts were also detected in midgestational (11.5 days) embryos by RT-PCR. Antisense expression did not increase when embryos were explanted and cultured for 48 h (9.5-11.5 days). The apparent reciprocal relationship between the abundance of sense and antisense bFGF transcripts in developing brain supports the possibility of a regulatory role for the antisense transcript in this tissue. There was no evidence for a reciprocal relationship between sense and antisense expression in the other tissues examined, indicating that the relationship between sense and antisense RNA expression may be tissue-specific.


Assuntos
Fator 2 de Crescimento de Fibroblastos/genética , Regulação da Expressão Gênica no Desenvolvimento , RNA Antissenso , Glândulas Suprarrenais/embriologia , Glândulas Suprarrenais/metabolismo , Animais , Northern Blotting , Encéfalo/embriologia , Encéfalo/metabolismo , Técnicas de Cultura , Embrião de Mamíferos/metabolismo , Feminino , Trabalho de Parto , Fígado/embriologia , Fígado/metabolismo , Masculino , Poli A/metabolismo , Gravidez , RNA Mensageiro , Ratos , Ratos Sprague-Dawley , Testículo/embriologia , Testículo/metabolismo
17.
Nature ; 378(6552): 92-6, 1995 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-7477299

RESUMO

Adipocyte differentiation involves the transcriptional activation of several genes in triglyceride metabolism, including the adipose P2 (aP2 or 422) gene that encodes the adipocyte lipid-binding protein ALBP. Within the mouse aP2 promoter region, the AE-1 sequence functions as either a positive or a negative element in the regulation of aP2 gene expression. The AE-1 sequence is the binding site for the positive murine (3T3) adipocyte factor C/EBP-alpha, several human preadipocyte factors, and a 3T3 preadipocyte factor(s) that has been implicated as a repressor of aP2 gene expression. Here we report the cloning of new complementary DNAs that encode the 3T3 preadipocyte factor (termed AEBP1) and demonstrate that AEBP1 expression is abolished during adipocyte differentiation. Furthermore, we show that an activity of a carboxypeptidase associated with AEBP1 is important in the transcriptional repression function of AEBP1. Thus AEBP1 might represent a new type of transcription factor that regulates transcription by cleavage of factors involved in transcription.


Assuntos
Adipócitos/metabolismo , Carboxipeptidases/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Repressoras/metabolismo , Células 3T3 , Adipócitos/citologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Ligação ao Cálcio , Carboxipeptidases/genética , Diferenciação Celular , Cloranfenicol O-Acetiltransferase/genética , Clonagem Molecular , DNA Complementar , Escherichia coli , Mutação da Fase de Leitura , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Membrana/genética , Camundongos , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Repressoras/genética , Deleção de Sequência
18.
Arch Biochem Biophys ; 240(2): 613-20, 1985 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-3896147

RESUMO

The antifungal agent, Sinefungin (SF), has been shown to be an inhibitor of transmethylation reactions. We report here the effects of SF on the production and methylation of rRNA in the yeast, Saccharomyces cerevisiae. Under conditions of SF treatment which have been shown to affect the regulation of cell proliferation in this yeast, pulse-chase labeling experiments using [methyl-3H]methionine and [3H]uracil indicated that methyl incorporation into rRNA during a short labeling period was inhibited, and stable 18 S rRNA production was differentially decreased. Other experiments quantitating modified nucleotides in newly produced rRNA showed that stable molecules were methylated. Taken together, these results suggest that SF slows methylation of rRNA, and is associated with differential loss of undermethylated 18 S rRNA species.


Assuntos
Adenosina/análogos & derivados , RNA Ribossômico/biossíntese , Saccharomyces cerevisiae/genética , Adenosina/farmacologia , Divisão Celular/efeitos dos fármacos , Metionina/metabolismo , Metilação , Uracila/metabolismo
19.
J Bacteriol ; 160(3): 1196-8, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6389512

RESUMO

Diploid formation by haploid cells of Saccharomyces cerevisiae was tested during and after treatment with chemical agents which bring about arrest at the cell cycle regulatory step "start." All compounds, except sinefungin, allowed efficient mating. During sinefungin treatment, zygote formation, but not karyogamy, was affected.


Assuntos
Saccharomyces cerevisiae/genética , Cruzamentos Genéticos , Interfase , Saccharomyces cerevisiae/citologia , Especificidade da Espécie
20.
Can J Microbiol ; 28(7): 860-73, 1982 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6293695

RESUMO

Bacteriocin 28, produced by Clostridium perfringens, was characterized by gel filtration and sodium dodecyl sulfate - polyacrylamide gel electrophoresis as a glycoprotein with a molecule weight of approximately 100,000. Density gradient centrifugation suggested a lower weight of 84,000. The bacteriocin bound firmly to phenyl-Sepharose CL-4B gel, indicating hydrophobic properties, and elution from this gel with ethylene glycol clearly separated bacteriocin from the alpha and theta toxins of C. perfringens, the latter of which was also hydrophobic. Bacteriocin 28 was immunogenic, inducing neutralizing and precipitating antibodies, and possessed three isoelectric points: 7.37, 7.05, and 5.4. Amino acid and carbohydrate analysis of the active material showed a composition of 15 amino acids and several carbohydrates. The molecule demonstrated instability with increasing purification, and several approaches to purification are described.


Assuntos
Bacteriocinas/isolamento & purificação , Clostridium perfringens/metabolismo , Bacteriocinas/análise , Carboidratos/análise , Centrifugação com Gradiente de Concentração , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Focalização Isoelétrica , Peso Molecular
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