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1.
Proc Natl Acad Sci U S A ; 118(51)2021 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-34911754

RESUMO

Autoantigen discovery is a critical challenge for the understanding and diagnosis of autoimmune diseases. While autoantibody markers in current clinical use have been identified through studies focused on individual disorders, we postulated that a reverse approach starting with a putative autoantigen to explore multiple disorders might hold promise. We here targeted the epidermal protein transglutaminase 1 (TGM1) as a member of a protein family prone to autoimmune attack. By screening sera from patients with various acquired skin disorders, we identified seropositive subjects with the blistering mucocutaneous disease paraneoplastic pemphigus. Validation in further subjects confirmed TGM1 autoantibodies as a 55% sensitive and 100% specific marker for paraneoplastic pemphigus. This gene-centric approach leverages the wealth of data available for human genes and may prove generally applicable for biomarker discovery in autoimmune diseases.


Assuntos
Autoantígenos/sangue , Síndromes Paraneoplásicas/imunologia , Pênfigo/imunologia , Transglutaminases/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Paraneoplásicas/sangue , Pênfigo/sangue , Adulto Jovem
2.
Aesthet Surg J ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874166

RESUMO

BACKGROUND: Hyaluronic acid dermal fillers are used for multiple indications including wrinkle correction and restoration of volume/fullness. OBJECTIVES: To compare the efficacy and safety of two hyaluronic acid products for correcting moderate to severe nasolabial folds. METHODS: A prospective randomized double-blind split-face study. Subjects' left and right NLF were randomized for treatment with DKL23 and Juvéderm Volift. Follow-up was conducted at 1, 3, 6, and 9 months. The changes from baseline in wrinkle severity rating scale (WSRS) and Global Aesthetics Improvement Scale (GAIS) were evaluated. Post-treatment adverse events (AEs) were recorded. RESULTS: Forty-eight women (median age, 57.0 years) with skin type I-VI were enrolled. Both treatments showed statistically significant improvement (p<0.0001) in NLFs according to WSRS score from baseline to each of the timepoints assessed. The improvement in NLFs was maintained until the end of the study (9 months). Furthermore, the change from baseline to each of the timepoints assessed was similar between DKL23 and Juvéderm Volift. Investigator- and subject-rated GAIS showed similar rates of improvement (indicated by the sum of responses of improved, much or very much improved) between the 2 products. AEs reported in the study were in line with prior and expected experience after injection of hyaluronic acid dermal fillers. The types of AEs, their rates, intensity and duration were comparable between the 2 products. CONCLUSIONS: DKL23 improved NLF severity from baseline and up to 9 months with comparable improvement to that shown by Juvéderm Volift. Treatment was safe and well tolerated.

3.
Angiogenesis ; 24(3): 597-611, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33629198

RESUMO

Antibiotic-induced microbial imbalance, or dysbiosis, has systemic and long-lasting effects on the host and response to cancer therapies. However, the effects on tumor endothelial cells are largely unknown. Therefore, the goal of the current study was to generate matched B16-F10 melanoma associated endothelial cell lines isolated from mice with and without antibiotic-induced dysbiosis. After validating endothelial cell markers on a genomic and proteomic level, functional angiogenesis assays (i.e., migration and tube formation) also confirmed their vasculature origin. Subsequently, we found that tumor endothelial cells derived from dysbiotic mice (TEC-Dys) were more sensitive to ionizing radiotherapy in the range of clinically-relevant hypofractionated doses, as compared to tumor endothelial cells derived from orthobiotic mice (TEC-Ortho). In order to identify tumor vasculature-associated drug targets during dysbiosis, we used tandem mass tag mass spectroscopy and focused on the statistically significant cellular membrane proteins overexpressed in TEC-Dys. By these criteria c-Met was the most differentially expressed protein, which was validated histologically by comparing tumors with or without dysbiosis. Moreover, in vitro, c-Met inhibitors Foretinib, Crizotinib and Cabozantinib were significantly more effective against TEC-Dys than TEC-Ortho. In vivo, Foretinib inhibited tumor growth to a greater extent during dysbiosis as compared to orthobiotic conditions. Thus, we surmise that tumor response in dysbiotic patients may be greatly improved by targeting dysbiosis-induced pathways, such as c-Met, distinct from the many targets suppressed due to dysbiosis.


Assuntos
Disbiose , Células Endoteliais/enzimologia , Melanoma Experimental , Neovascularização Patológica , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met , Animais , Disbiose/enzimologia , Disbiose/microbiologia , Melanoma Experimental/irrigação sanguínea , Melanoma Experimental/enzimologia , Melanoma Experimental/microbiologia , Melanoma Experimental/terapia , Camundongos , Neovascularização Patológica/enzimologia , Neovascularização Patológica/microbiologia , Neovascularização Patológica/terapia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/metabolismo , Radioterapia
4.
Nanotechnology ; 30(27): 275102, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30901766

RESUMO

Carbon-based nanomaterials (CBNs) were previously described as regulators of plant cell division. Here, we demonstrated the ability of multi-walled carbon nanotubes (MWCNT) and graphene to enhance biomass production in callus culture of the medicinal plant Catharanthus roseus cultivated in dark conditions. Furthermore, both tested CBNs were able to stimulate biosynthesis of total produced alkaloids in CBN-exposed callus culture of Catharanthus. In one case, total alkaloids in CBN-exposed Catharanthus were double that of unexposed Catharanthus. Analysis of metabolites by HPLC revealed that production of the pharmaceutically active alkaloids vinblastine and vincristine was dramatically enhanced in callus exposed to MWCNT or graphene in both dark and light conditions of callus cultivation. In vitro assays (MTT, flow cytometry) demonstrated that total alkaloid extracts derived from Catharanthus callus treated with CBNs significantly reduced cell proliferation of breast cancer (MCF-7) and lung cancer (A549) cell lines compared to the application of extracts derived from untreated Catharanthus callus.


Assuntos
Alcaloides/biossíntese , Alcaloides/farmacologia , Catharanthus/química , Catharanthus/crescimento & desenvolvimento , Nanotubos de Carbono/química , Células A549 , Catharanthus/efeitos dos fármacos , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Grafite/farmacologia , Humanos , Células MCF-7 , Necrose , Extratos Vegetais/farmacologia , Vimblastina/farmacologia
5.
J Asthma ; 55(3): 275-283, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28463525

RESUMO

BACKGROUND: Allergic and non-allergic asthma are viewed as separate entities, despite sharing similarities. The aims of this study were to determine differences in symptoms from the upper airways and the skin in allergic and non-allergic asthma. The secondary aims were to identify childhood risk factors and to compare quality of life in the two asthma groups. METHODS: This cohort (age 17-76 years) consisted of 575 subjects with allergic or non-allergic asthma and 219 controls. The participants participated in an interview, spirometry, FeNO, skin prick test, and responded to the Mini Asthma Quality of Life Questionnaire. RESULTS: Self-reported allergic rhinitis was significantly more common in both allergic and non-allergic asthma (82.3 and 40.7%) groups compared with the controls. The prevalence of chronic rhinosinusitis (CRS) was similar in both asthma groups. Eczema was significantly more common in both asthmatic groups (72.3 and 59.8%) than controls (47.0%) (p < 0.001 and p = 0.012). Severe respiratory infection in childhood and parental allergy were risk factors for both allergic and non-allergic asthma groups. Quality of life was significantly lower in non-allergic than allergic asthma groups (p = 0.01). CONCLUSION: Concomitant symptoms from the upper airways and the skin were significantly more common in both allergic and non-allergic asthma. This indicates that non-allergic asthma has a systemic component with similarities to what is found in allergic asthma. There were similarities in the childhood risk factor pattern between the two types of asthma but asthma-related quality of life was lower in the non-allergic asthma group.


Assuntos
Asma/epidemiologia , Eczema/epidemiologia , Exantema/epidemiologia , Adulto , Asma/diagnóstico , Asma/metabolismo , Asma/fisiopatologia , Testes Respiratórios , Eczema/diagnóstico , Eczema/metabolismo , Eczema/fisiopatologia , Exantema/diagnóstico , Exantema/metabolismo , Exantema/fisiopatologia , Feminino , Humanos , Imunoglobulina E/sangue , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Pais , Qualidade de Vida , Testes Cutâneos , Espirometria , Inquéritos e Questionários , Suécia
6.
J Immunol ; 193(5): 2118-26, 2014 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25063864

RESUMO

The mechanisms behind destruction of the adrenal glands in autoimmune Addison's disease remain unclear. Autoantibodies against steroid 21-hydroxylase, an intracellular key enzyme of the adrenal cortex, are found in >90% of patients, but these autoantibodies are not thought to mediate the disease. In this article, we demonstrate highly frequent 21-hydroxylase-specific T cells detectable in 20 patients with Addison's disease. Using overlapping 18-aa peptides spanning the full length of 21-hydroxylase, we identified immunodominant CD8(+) and CD4(+) T cell responses in a large proportion of Addison's patients both ex vivo and after in vitro culture of PBLs ≤20 y after diagnosis. In a large proportion of patients, CD8(+) and CD4(+) 21-hydroxylase-specific T cells were very abundant and detectable in ex vivo assays. HLA class I tetramer-guided isolation of 21-hydroxylase-specific CD8(+) T cells showed their ability to lyse 21-hydroxylase-positive target cells, consistent with a potential mechanism for disease pathogenesis. These data indicate that strong CTL responses to 21-hydroxylase often occur in vivo, and that reactive CTLs have substantial proliferative and cytolytic potential. These results have implications for earlier diagnosis of adrenal failure and ultimately a potential target for therapeutic intervention and induction of immunity against adrenal cortex cancer.


Assuntos
Doença de Addison/imunologia , Linfócitos T CD8-Positivos/imunologia , Proliferação de Células , Imunidade Celular , Peptídeos/imunologia , Esteroide 21-Hidroxilase/imunologia , Doença de Addison/patologia , Adolescente , Neoplasias do Córtex Suprarrenal/imunologia , Neoplasias do Córtex Suprarrenal/patologia , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Humanos , Pessoa de Meia-Idade
7.
Dermatol Surg ; 42(8): 967-76, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27399956

RESUMO

BACKGROUND: Different volumes of 0.9% NaCl may be used to reconstitute abobotulinumtoxinA yielding an injection volume that ranges from 0.05 to 0.1 mL per injection point for treatment of glabellar lines. OBJECTIVE: To evaluate the efficacy, safety, and subject satisfaction of 2 different injection volumes to deliver the same unit dose of abobotulinumtoxinA for treatment of glabellar lines. MATERIALS AND METHODS: This randomized comparative study was conducted using 2 different reconstitution volumes to deliver a fixed unit dose of 10 Speywood units (sU) of abobotulinumtoxinA in either 0.05 mL (labeled volume) or 0.1 mL (twofold volume) per injection point. Evaluations included wrinkle severity, neurophysiological assessment by compound muscle action potential (CMAP), and subject satisfaction. RESULTS: Use of either injection volume of abobotulinumtoxinA resulted in the early onset of effect, high effectiveness, and long duration of effect. The safety profile and injection pain levels were similar in both groups. The twofold injection volume was shown to be noninferior to the labeled injection volume based on CMAP results. CONCLUSION: A twofold increase in injection volume to 0.1 mL per injection point to deliver 10 sU of abobotulinumtoxinA is effective and safe.


Assuntos
Inibidores da Liberação da Acetilcolina/administração & dosagem , Toxinas Botulínicas Tipo A/administração & dosagem , Músculo Esquelético/efeitos dos fármacos , Satisfação do Paciente , Envelhecimento da Pele/efeitos dos fármacos , Inibidores da Liberação da Acetilcolina/efeitos adversos , Potenciais de Ação , Adulto , Toxinas Botulínicas Tipo A/efeitos adversos , Feminino , Testa , Humanos , Pessoa de Meia-Idade , Músculo Esquelético/fisiologia , Dor/etiologia
8.
Planta ; 242(1): 123-35, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25893866

RESUMO

MAIN CONCLUSION: We demonstrate here that the reduction of InsP 3 , the key component of the phosphoinositol pathway, results in changes in ROS-scavenging machinery and, subsequently, increases the tolerance of tomato plants to light stress. Different plant stress signaling pathways share similar elements and, therefore, 'cross-talk' between the various pathways can exist. Links between the phosphoinositol signaling pathway and light signaling were recently found. Tomato plants expressing InsP 5-ptase and exhibiting reduction in the level of inositol 1,4,5-triphosphate (InsP3) demonstrated enhanced tolerance to stress caused by continuous light exposure. To understand the molecular basis of observed stress tolerance in tomato lines with decreased amount of InsP3, we monitored the expression of enzymatic antioxidants as well as important factors in light signaling associated with non-enzymatic antioxidants (secondary metabolites). Here, we demonstrated that InsP 5-ptase transgenic plants accumulate less hydroxide peroxide and maintain higher chlorophyll content during stress caused by continuous light exposure. This observation can be explained by documented activation of multiple enzymatic antioxidants (LeAPX1, SICAT2, LeSOD) at levels of gene expression and enzymatic activities during continuous light exposure. In addition, we noticed the up-regulation of photoreceptors LePHYB and LeCHS1, key enzymes in flavonoid biosynthesis pathway, transcription factors LeHY5, SIMYB12, and early light-inducible protein (LeELIP) genes in transgenic tomato seedlings exposed to blue or red light. Our study confirmed the existence of a correlation between phosphoinositol signaling pathway modification, increased tolerance to stress caused by continuous light exposure, activation of ROS-scavenging enzymes, and up-regulation of molecular activators of non-enzymatic antioxidants in InsP 5-ptase expressing tomato lines.


Assuntos
Adaptação Fisiológica , Inositol 1,4,5-Trifosfato/metabolismo , Estresse Oxidativo , Solanum lycopersicum/genética , Solanum lycopersicum/fisiologia , Adaptação Fisiológica/efeitos da radiação , Antioxidantes/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Peróxido de Hidrogênio/metabolismo , Inositol Polifosfato 5-Fosfatases , Luz , Transdução de Sinal Luminoso/efeitos da radiação , Solanum lycopersicum/enzimologia , Solanum lycopersicum/efeitos da radiação , Modelos Biológicos , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/efeitos da radiação , Monoéster Fosfórico Hidrolases/metabolismo , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
9.
Acta Derm Venereol ; 95(8): 948-51, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25766591

RESUMO

Despite the extensive use of botulinum toxin A (BoNTA) in medical and cosmetic treatments, the potential spreading of BoNTA to surrounding tissues remains unknown. A patient with hemifacial paralysis upon blepharospasm treatment with low dose of BoNTA, prompted us to investigate the spreading effect. A randomised, double-blind study was conducted in which 5 healthy women (33-52 years) were treated with different doses of onabotulinum toxin unilaterally in the corrugator muscle. Parameters of efficacy and diffusion (CMAP; EMG and jitter analysis) in both glabellar and frontalis muscles were assessed at baseline, 2 and 4 weeks following BoNTA injection. CMAP of the treated glabellar muscles was reduced to approximately 40% in all dose groups. Additionally, contralateral CMAP reduction was observed in 3 of 5 subjects. These data confirm regional diffusion of BoNTA in facial muscle application, which raises question on the reliability of split-face models in BoNTA studies.


Assuntos
Inibidores da Liberação da Acetilcolina/farmacocinética , Toxinas Botulínicas Tipo A/farmacocinética , Músculos Faciais/metabolismo , Inibidores da Liberação da Acetilcolina/administração & dosagem , Inibidores da Liberação da Acetilcolina/efeitos adversos , Potenciais de Ação/efeitos dos fármacos , Adulto , Idoso de 80 Anos ou mais , Blefarospasmo/tratamento farmacológico , Toxinas Botulínicas Tipo A/administração & dosagem , Toxinas Botulínicas Tipo A/efeitos adversos , Ensaios Clínicos Controlados como Assunto/métodos , Difusão , Método Duplo-Cego , Eletromiografia , Músculos Faciais/efeitos dos fármacos , Paralisia Facial/induzido quimicamente , Feminino , Testa , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Projetos de Pesquisa
10.
Acta Derm Venereol ; 94(1): 32-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23975053

RESUMO

Despite the extensive use of botulinum toxin type A (BoNT-A) in treatments for glabellar frown lines, the dose-response effect in the glabellar muscles remains unknown. The aim of this randomized, double-blind, placebo-controlled prospective study was to characterize the neurophysiological parameters that correlate with the effect of BoNT-A in the glabellar muscles and its diffusion to surrounding ocular muscles. Sixteen healthy women were recruited and randomized to 3 different dose-groups of onabotulinumtoxin A (Vistabel®) or placebo and followed 24 weeks by neuro-physiological examinations. Efficacy of treatment on corrugator supercilii muscles was measured by compound motor action potential (CMAP) and electromyography (EMG). Photographs were used to score glabellar frown lines. Diffusion of the drug to surrounding muscles was assessed by CMAP of the nasalis muscle, EMG and concentric needle electrode jitter analysis (CNE) of the orbicularis oculi muscle. CMAP reduction correlated well with intramuscular BoNT-A dose. Muscle paralysis, measured by EMG, began from 2 weeks and was not entirely reversed at 24 weeks in individuals who received high dose of onabotulinumtoxin. Limited diffusion of orbicularis oculi was detected with CNE. In conclusion, we developed a novel neurophysiological strategy for effect evaluation of BoNT-A in glabellar muscles. CMAP and EMG correlated with given BoNT-A dose and are more defined effect measures than clinical glabellar photo scales.


Assuntos
Toxinas Botulínicas Tipo A/administração & dosagem , Músculos Faciais/efeitos dos fármacos , Fármacos Neuromusculares/administração & dosagem , Potenciais de Ação , Adulto , Toxinas Botulínicas Tipo A/efeitos adversos , Técnicas Cosméticas , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletromiografia , Músculos Faciais/fisiologia , Feminino , Humanos , Injeções Intramusculares , Pessoa de Meia-Idade , Fenômenos Fisiológicos Oculares/efeitos dos fármacos , Fotografação , Estudos Prospectivos , Envelhecimento da Pele/efeitos dos fármacos
11.
Small ; 9(1): 115-23, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23019062

RESUMO

Multi-walled carbon nanotubes (CNTs) can affect plant phenotype and the composition of soil microbiota. Tomato plants grown in soil supplemented with CNTs produce two times more flowers and fruit compared to plants grown in control soil. The effect of carbon nanotubes on microbial community of CNT-treated soil is determined by denaturing gradient gel electrophoresis and pyrosequencing analysis. Phylogenetic analysis indicates that Proteobacteria and Bacteroidetes are the most dominant groups in the microbial community of soil. The relative abundances of Bacteroidetes and Firmicutes are found to increase, whereas Proteobacteria and Verrucomicorbia decrease with increasing concentration of CNTs. The results of comparing diversity indices and species level phylotypes (OTUs) between samples showed that there is not a significant affect on bacterial diversity.


Assuntos
Nanotubos de Carbono/química , Reguladores de Crescimento de Plantas/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Animais , Eletroforese/métodos , Flores , Frutas , Humanos , Solanum lycopersicum/metabolismo , Nanotecnologia/métodos , Fenótipo , Filogenia , Fenômenos Fisiológicos Vegetais , RNA Ribossômico 16S/química , Análise de Sequência de DNA/métodos , Solo/análise , Microbiologia do Solo , Análise Espectral Raman/métodos
12.
Clin Neurophysiol Pract ; 8: 169-173, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37681120

RESUMO

Aesthetic use of low doses of Botulinum toxin (BoNT) injections into the facial muscles has become a leading non-surgical aesthetic treatment worldwide to reduce facial wrinkles, including glabellar lines, forehead lines, and periorbital wrinkles. Within these aesthetic applications, BoNT injections intend to reduce and prevent wrinkles, and the recommended usage of 2 years is often exceeded, which may result in atrophy of the injected muscles. The long-term effects of BoNT injections in the facial muscles and the evidence of diffusion of BoNT to surrounding muscles are obvious pitfalls and challenges for clinical neurophysiologists in differential diagnosing neuromuscular transmission failures. Also, this is further complicated by the risk of developing side effects upon permanent chemical denervation of facial muscles, with less possibility for reinnervation. This review summarizes the known long-term effects of BoNT over time in different facial muscles and the use of objective electrophysiological measures to evaluate these. A better understanding of the long-term effects of BoNT is essential to avoid misdiagnosing other neuromuscular disorders.

13.
Cureus ; 15(10): e47838, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38021529

RESUMO

BACKGROUND: Post-traumatic elbow stiffness (PTES) may substantially affect the patient's functional range of motion and quality of life. Open elbow release has been extensively studied, but arthroscopic techniques are limited, particularly in differentiating between post-traumatic and non-traumatic stiffness. The purpose of this study is to assess the clinical outcomes after arthroscopic release of PTES regarding the range of motion (ROM), pain, functional assessment, and complications. METHODS: A prospective cohort was conducted on adult patients who underwent arthroscopic arthrolysis for PTES, with 32 patients included in the final analysis. The ROM was measured using the orthopedic goniometer. Grip strength was measured using the Camry digital hand dynamometer (Camry, CA, USA) and compared to their contralateral side. The functional status of the patients was evaluated using the American Shoulder and Elbow Surgeons Score (ASES)andthe Mayo Elbow Performance Index (MEPI). All measurements were done before surgery and at the last follow-up visit. Pre-operative and post-operative changes in MEPI, ASES, and visual analog (VAS) scores were compared with the paired t-test. RESULTS: After surgery, the ROM significantly improved from 74 ± 11 to 110 ± 15 degrees (p<0.001). Additionally, the ASES score and MEPI index both significantly improved from 69 ± 3.4 to 79 ± 6.3 and from 64 ± 5.7 to 82 ± 8, respectively (p<0.001). VAS scores also significantly improved from 1.1 ± 0.87 to 0.31 ± 0.53 at rest (p<0.001). The complication rate was 12%, including three transient ulnar nerve paresthesia and one superficial infection. Post-traumatic elbow release was more offered in distal humerus fractures (53%), followed by proximal ulna fracture/dislocations (25%). CONCLUSION: We believe that arthroscopic arthrolysis is a safe and reliable treatment of PTES, which improves joint visibility and reduces pain. Patients can be counseled regarding the risk of a secondary surgery following distal humerus or proximal ulna fractures, including the expected recovery and complication rate.

14.
Plant Mol Biol ; 79(1-2): 191-202, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22466452

RESUMO

DNA methylation in cytosine residues plays an important role in regulating gene expression. Densely methylated transgenes are often silenced. In contrast, several eukaryotic genomes express moderately methylated genes. These methylations are found in the CG context within the coding region (gene body). The role of gene body methylation in gene expression, however, is not clear. The Arabidopsis Phytochrome A epiallele, phyA', carries hypermethylation in several CG sites resident to the coding region. As a result, phyA' is transcriptionally silenced and confers strong mutant phenotype. Mutations in chromatin modification factors and RNAi genes failed to revert the mutant phenotype, suggesting the involvement of a distinct epigenetic mechanism associated with phyA' silencing. Using the forward genetics approach, a suppressor line, termed as suppressor of p hyA' silencing 1 (sps1), was isolated. Genetic and molecular analysis revealed that sps1 mutation reactivates the phyA' locus without altering its methylation density. However, hypomethylation at a specific CG site in exon 1 was consistently associated with the release of phyA' silencing. While gene underlying sps1 mutation is yet to be identified, microarray analysis suggested that its targets are the expressed genes or euchromatic loci in Arabidopsis genome. By identifying the association of phyA' silencing with the methylation of a specific CG site in exon 1, the present work shows that site-specific methylation confers greater effect on transcription than the methylation density within gene-body. Further, as the identified site (exon 1) is not critical for the promoter activity, transcription elongation rather than transcription initiation is likely to be affected by this site-specific CG methylation.


Assuntos
Alelos , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Metilação de DNA/genética , Inativação Gênica , Fases de Leitura Aberta/genética , Fitocromo A/genética , Transcrição Gênica , Southern Blotting , Segregação de Cromossomos/genética , Cruzamentos Genéticos , Epigênese Genética , Éxons/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes Supressores , Loci Gênicos/genética , Mutagênese/genética , Mutação/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Mapeamento Físico do Cromossomo , Sementes/genética
15.
J Exp Bot ; 63(2): 825-35, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21994174

RESUMO

The phosphoinositol pathway is one of the major eukaryotic signalling pathways. The metabolite of the phosphoinositol pathway, inositol- (1,4,5) trisphosphate (InsP(3)), is a regulator of plant responses to a wide variety of stresses, including light, drought, cold, and salinity. It was found that the expression of InsP 5-ptase, the enzyme that hydrolyses InsP(3), also dramatically affects the levels of inositol phosphate metabolites and the secondary metabolites in transgenic tomato plants. Tomato plants expressing InsP 5-ptase exhibited a reduction in the levels of several important inositol phosphates, including InsP(1), InsP(2), InsP(3), and InsP(4). Reduced levels of inositol phosphates accompanied an increase in the accumulation of phenylpropanoids (rutin, chlorogenic acid) and ascorbic acid (vitamin C) in the transgenic fruits of tomato plants. The enhanced accumulation of these metabolites in transgenic tomato plants was in direct correspondence with the observed up-regulation of the genes that express the key enzymes of ascorbic acid metabolism (myo-inositol oxygenase, MIOX; L-galactono-γ-lactone dehydrogenase, GLDH) and phenylpropanoid metabolism (chalcone synthase, CHS1; cinnamoyl-CoA shikimate/quinate transferase, HCT). To understand the molecular links between the activation of different branches of plant metabolism and InsP(3) reduction in tomato fruits, the expression of transcription factors known to be involved in light signalling was analysed by real-time RT-PCR. The expression of LeHY5, SIMYB12, and LeELIP was found to be higher in fruits expressing InsP 5-ptase. These results suggest possible interconnections between phosphoinositol metabolism, light signalling, and secondary metabolism in plants. Our study also revealed the biotechnological potential for the genetic improvement of crop plants by the manipulation of the phosphoinositol pathway.


Assuntos
Inositol 1,4,5-Trifosfato/metabolismo , Fosfatos de Inositol/metabolismo , Transdução de Sinal Luminoso/fisiologia , Monoéster Fosfórico Hidrolases/metabolismo , Solanum lycopersicum/fisiologia , Ácido Ascórbico/metabolismo , Secas , Flavonoides/análise , Flavonoides/metabolismo , Frutas/enzimologia , Frutas/genética , Frutas/fisiologia , Regulação da Expressão Gênica de Plantas/genética , Inositol 1,4,5-Trifosfato/análise , Fosfatos de Inositol/análise , Inositol Polifosfato 5-Fosfatases , Solanum lycopersicum/enzimologia , Solanum lycopersicum/genética , Modelos Biológicos , Monoéster Fosfórico Hidrolases/genética , Plantas Geneticamente Modificadas , Estresse Fisiológico/fisiologia , Regulação para Cima/genética
16.
Proc Natl Acad Sci U S A ; 106(11): 4396-401, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19251657

RESUMO

Patients with autoimmune polyendocrine syndrome type 1 (APS-1) suffer from multiple organ-specific autoimmunity with autoantibodies against target tissue-specific autoantigens. Endocrine and nonendocrine organs such as skin, hair follicles, and liver are targeted by the immune system. Despite sporadic observations of pulmonary symptoms among APS-1 patients, an autoimmune mechanism for pulmonary involvement has not been elucidated. We report here on a subset of APS-1 patients with respiratory symptoms. Eight patients with pulmonary involvement were identified. Severe airway obstruction was found in 4 patients, leading to death in 2. Immunoscreening of a cDNA library using serum samples from a patient with APS-1 and obstructive respiratory symptoms identified a putative potassium channel regulator (KCNRG) as a pulmonary autoantigen. Reactivity to recombinant KCNRG was assessed in 110 APS-1 patients by using immunoprecipitation. Autoantibodies to KCNRG were present in 7 of the 8 patients with respiratory symptoms, but in only 1 of 102 APS-1 patients without respiratory symptoms. Expression of KCNRG messenger RNA and protein was found to be predominantly restricted to the epithelial cells of terminal bronchioles. Autoantibodies to KCNRG, a protein mainly expressed in bronchial epithelium, are strongly associated with pulmonary involvement in APS-1. These findings may facilitate the recognition, diagnosis, characterization, and understanding of the pulmonary manifestations of APS-1.


Assuntos
Autoantígenos/imunologia , Autoimunidade/imunologia , Brônquios/imunologia , Pneumopatias/imunologia , Poliendocrinopatias Autoimunes/complicações , Poliendocrinopatias Autoimunes/imunologia , Canais de Potássio/imunologia , Obstrução das Vias Respiratórias , Autoanticorpos/análise , Bronquíolos/imunologia , Bronquíolos/patologia , Causas de Morte , Células Epiteliais/imunologia , Biblioteca Gênica , Humanos , Imunoprecipitação , Pneumopatias/etiologia , Canais de Potássio/análise , Canais de Potássio/genética , Doença Pulmonar Obstrutiva Crônica/imunologia , RNA Mensageiro/análise , Proteínas Recombinantes/imunologia
17.
N Engl J Med ; 358(10): 1018-28, 2008 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-18322283

RESUMO

BACKGROUND: Autoimmune polyendocrine syndrome type 1 (APS-1) is a multiorgan autoimmune disorder caused by mutations in AIRE, the autoimmune regulator gene. Though recent studies concerning AIRE deficiency have begun to elucidate the molecular pathogenesis of organ-specific autoimmunity in patients with APS-1, the autoantigen responsible for hypoparathyroidism, a hallmark of APS-1 and its most common autoimmune endocrinopathy, has not yet been identified. METHODS: We performed immunoscreening of a human parathyroid complementary DNA library, using serum samples from patients with APS-1 and hypoparathyroidism, to identify patients with reactivity to the NACHT leucine-rich-repeat protein 5 (NALP5). Subsequently, serum samples from 87 patients with APS-1 and 293 controls, including patients with other autoimmune disorders, were used to determine the frequency and specificity of autoantibodies against NALP5. In addition, the expression of NALP5 was investigated in various tissues. RESULTS: NALP5-specific autoantibodies were detected in 49% of the patients with APS-1 and hypoparathyroidism but were absent in all patients with APS-1 but without hypoparathyroidism, in all patients with other autoimmune endocrine disorders, and in all healthy controls. NALP5 was predominantly expressed in the cytoplasm of parathyroid chief cells. CONCLUSIONS: NALP5 appears to be a tissue-specific autoantigen involved in hypoparathyroidism in patients with APS-1. Autoantibodies against NALP5 appear to be highly specific and may be diagnostic for this prominent component of APS-1.


Assuntos
Autoanticorpos/sangue , Autoantígenos/imunologia , Hipoparatireoidismo/diagnóstico , Glândulas Paratireoides/imunologia , Poliendocrinopatias Autoimunes/imunologia , Autoanticorpos/análise , Autoantígenos/genética , Biomarcadores/análise , Biomarcadores/sangue , DNA Complementar/análise , Biblioteca Gênica , Humanos , Hipoparatireoidismo/etiologia , Hipoparatireoidismo/imunologia , Proteínas Mitocondriais , Proteínas Nucleares , Glândulas Paratireoides/química , Poliendocrinopatias Autoimunes/complicações , RNA Mensageiro/análise
19.
Nanotechnology ; 22(29): 295101, 2011 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-21673379

RESUMO

Plant seedlings were exposed to single-walled carbon nanotube-quantum dot conjugates (SWCNT-QD) mixed in the growth medium in order to understand the interactions between these multicomponent nanosystems and plants. A combination of fluorescent and Raman-scattering 2D mapping analysis was used to clearly monitor the presence of the SWCNT-QD conjugates in various parts of the tomato seedlings. We found that the addition of QDs to SWCNTs dramatically changed the biological viability of the tomato plants by significantly accelerating leaf senescence and inhibiting root formation. Although the exposure of SWCNTs only to the plants induced positive effects, the chlorophyll content decreased by 1.5-fold in leaves, and the total weight of the root system decreased four times for the tomato plants exposed to SWCNT-QDs (50 µg ml(-1)) compared to plants grown on regular medium as controls. Our results clearly indicate that the exposure of plants to multicomponent nanomaterials is highly influenced by the presence and bioactivity of each component, individually. Such studies could be the foundation for understanding how complex nanosized systems affect the activity of various biological systems with a major impact on ecotoxicology.


Assuntos
Nanotecnologia/métodos , Nanotubos de Carbono/química , Pontos Quânticos , Solanum lycopersicum/fisiologia , Biomassa , Clorofila/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Nanotubos de Carbono/ultraestrutura , Folhas de Planta/química , Raízes de Plantas/crescimento & desenvolvimento , Plântula/fisiologia , Análise Espectral Raman
20.
Clin Endocrinol (Oxf) ; 73(5): 630-6, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20718774

RESUMO

OBJECTIVE: To assess autoimmune regulator (AIRE) gene mutations, class II HLA haplotypes, and organ- or non-organ-specific autoantibodies in patients with chronic hypoparathyroidism (CH) without associated Addison's disease (AD) or chronic candidiasis (CC). DESIGN, PATIENTS AND MEASUREMENTS: Twenty-four patients who had CH without AD or CC were included in the study. AIRE gene mutations in all 14 exons were studied using PCR in 24 patients, 105 healthy controls and 15 first-degree relatives of CH patients with AIRE mutations. Human leucocyte antigens (HLA) were determined for all 24 patients and 105 healthy controls. Autoantibodies to a range of antigens including NACHT leucine-rich-repeat protein-5 (NALP5) and interferon omega (IFNω) were tested in all 24 patients. RESULTS: AIRE gene mutations were found in 6 of 24 (25%) patients, all females, and this was significantly higher (P < 0·001) compared with AIRE mutations found in healthy controls (2/105). Three patients (12·5%) had homozygous AIRE mutations characteristic of Autoimmune-Poly-Endocrinopathy-Candidiasis-Ectodermal-Dystrophy and all three were also positive for IFNω-autoantibodies. Three patients (12·5%) had heterozygous AIRE mutations; two of these were novel mutations. One of the patients with heterozygous AIRE mutations was positive for both NACHT leucine-rich-repeat protein 5 and IFNω autoantibodies. Heterozygous AIRE mutations were found in 10 of 15 first-degree relatives of CH patients with AIRE mutations, although none was affected by CH. Class II HLA haplotypes were not statistically different in patients with CH compared to healthy controls. CONCLUSIONS: Analysis of AIRE gene mutations together with serum autoantibody profile should be helpful in the assessment of patients with CH, in particular young women with associated autoimmune diseases.


Assuntos
Autoanticorpos/sangue , Hipoparatireoidismo/genética , Interferon Tipo I/imunologia , Poliendocrinopatias Autoimunes/genética , Fatores de Transcrição/genética , Adulto , Idoso , Criança , Pré-Escolar , Doença Crônica , Feminino , Antígenos HLA/sangue , Humanos , Hipoparatireoidismo/imunologia , Masculino , Pessoa de Meia-Idade , Poliendocrinopatias Autoimunes/imunologia , Proteína AIRE
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