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1.
Mol Cell ; 83(9): 1462-1473.e5, 2023 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-37116493

RESUMO

DNA binding domains (DBDs) of transcription factors (TFs) recognize DNA sequence motifs that are highly abundant in genomes. Within cells, TFs bind a subset of motif-containing sites as directed by either their DBDs or DBD-external (nonDBD) sequences. To define the relative roles of DBDs and nonDBDs in directing binding preferences, we compared the genome-wide binding of 48 (∼30%) budding yeast TFs with their DBD-only, nonDBD-truncated, and nonDBD-only mutants. With a few exceptions, binding locations differed between DBDs and TFs, resulting from the cumulative action of multiple determinants mapped mostly to disordered nonDBD regions. Furthermore, TFs' preferences for promoters of the fuzzy nucleosome architecture were lost in DBD-only mutants, whose binding spread across promoters, implicating nonDBDs' preferences in this hallmark of budding yeast regulatory design. We conclude that DBDs and nonDBDs employ complementary DNA-targeting strategies, whose balance defines TF binding specificity along genomes.


Assuntos
DNA , Fatores de Transcrição , Sítios de Ligação , Fatores de Transcrição/metabolismo , Ligação Proteica , DNA/genética
2.
Mol Cell ; 79(3): 459-471.e4, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32553192

RESUMO

Transcription factors (TFs) that bind common DNA motifs in vitro occupy distinct sets of promoters in vivo, raising the question of how binding specificity is achieved. TFs are enriched with intrinsically disordered regions (IDRs). Such regions commonly form promiscuous interactions, yet their unique properties might also benefit specific binding-site selection. We examine this using Msn2 and Yap1, TFs of distinct families that contain long IDRs outside their DNA-binding domains. We find that these IDRs are both necessary and sufficient for localizing to the majority of target promoters. This IDR-directed binding does not depend on any localized domain but results from a multitude of weak determinants distributed throughout the entire IDR sequence. Furthermore, IDR specificity is conserved between distant orthologs, suggesting direct interaction with multiple promoters. We propose that distribution of sensing determinants along extended IDRs accelerates binding-site detection by rapidly localizing TFs to broad DNA regions surrounding these sites.


Assuntos
Proteínas de Ligação a DNA/genética , Regulação Fúngica da Expressão Gênica , Proteínas Intrinsicamente Desordenadas/genética , Motivos de Nucleotídeos , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Deleção de Sequência , Fatores de Transcrição/genética , Sítios de Ligação , Biologia Computacional/métodos , Sequência Conservada , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Proteínas Intrinsicamente Desordenadas/química , Proteínas Intrinsicamente Desordenadas/metabolismo , Modelos Estatísticos , Regiões Promotoras Genéticas , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
3.
Nucleic Acids Res ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38908024

RESUMO

Intrinsically disordered regions (IDRs) guide transcription factors (TFs) to their genomic binding sites, raising the question of how structure-lacking regions encode for complex binding patterns. We investigated this using the TF Gln3, revealing sets of IDR-embedded determinants that direct Gln3 binding to respective groups of functionally related promoters, and enable tuning binding preferences between environmental conditions, phospho-mimicking mutations, and orthologs. Through targeted mutations, we defined the role of short linear motifs (SLiMs) and co-binding TFs (Hap2) in stabilizing Gln3 at respiration-chain promoters, while providing evidence that Gln3 binding at nitrogen-associated promoters is encoded by the IDR amino-acid composition, independent of SLiMs or co-binding TFs. Therefore, despite their apparent simplicity, TF IDRs can direct and regulate complex genomic binding patterns through a combination of SLiM-mediated and composition-encoded interactions.

4.
J Cell Physiol ; 239(1): 135-151, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37942831

RESUMO

In tandem with the expanding obesity pandemic, the prevalence of metabolic dysfunction associated steatohepatitis (MASH, formerly known as NASH)- driven hepatocellular carcinoma (HCC) is predicted to rise globally, creating a significant need for therapeutic interventions. We previously identified the upregulation of apoptosis antagonizing transcription factor (AATF), which is implicated in facilitating the progression from MASH to HCC. The objective of this study was to examine whether the intervention of curcumin could alleviate AATF-mediated MASH, inhibit tumor growth, and elucidate the underlying mechanism. A preclinical murine model mimicking human MASH-HCC was employed, subjecting mice to either a chow diet normal water (CDNW) or western diet sugar water (WDSW) along with very low dose of carbon tetrachloride (CCl4 - 0.2 µL/g, weekly). Mice receiving curcumin (CUR) alongside WDSW/CCl4 exhibited significant improvements, including reduced liver enzymes, dyslipidemia, steatosis, inflammation, and hepatocellular ballooning. Curcumin treatment also suppressed hepatic expression of inflammatory, fibrogenic, and oncogenic markers. Of note, there was a significant reduction in the expression of AATF upon curcumin treatment in WDSW/CCl4 mice and human HCC cells. In contrast, curcumin upregulated Kruppel-like factor 4 (KLF4) in MASH liver and HCC cells, which is known to downregulate sp1 (specificity protein-1) expression. Thus, curcumin treatment effectively inhibited the progression of MASH to HCC by downregulating the expression of AATF via the KLF4-Sp1 signaling pathway. These preclinical findings establish a novel molecular connection between curcumin and AATF in reducing hepatocarcinogenesis, and provide a strong rationale for the development of curcumin as a viable treatment for MASH-HCC in humans.


Assuntos
Carcinoma Hepatocelular , Curcumina , Fígado Gorduroso , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Apoptose , Proteínas Reguladoras de Apoptose , Carcinoma Hepatocelular/patologia , Curcumina/farmacologia , Curcumina/uso terapêutico , Fígado Gorduroso/patologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Repressoras , Fatores de Transcrição
5.
Lasers Med Sci ; 39(1): 82, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418665

RESUMO

Aim of this study is to assess the clinical efficacy of 445 nm Diode laser as an adjunct to Kirkland flap surgery in management of periodontitis. Type of study is a Split mouth clinical trial in which a total of 13 patients were recruited based on specific inclusion and exclusion criteria. In each participant, random allocation of selected sites into test and control in contralateral quadrants was done. Clinical parameters such as probing depth and clinical attachment loss was measured in control and test sites using occlusal stents. Flap surgery was carried out 6 weeks after phase I therapy and the selected contralateral sites with a probing depth of > 5mm were subjected to surgical therapy. In a test quadrant, 445 nm diode laser with a power of 0.8 W, CW mode, 320 µm fiber, in non-contact mode was used as an adjunct to flap surgery. Primary outcome variable assessed was change in PPD between baseline, pre-operative, 1-, 3- and 6-months post-surgery. Secondary outcomes variables assessed were Clinical attachment loss at baseline, pre-operative, 1, 3 and 6 months, visual analog scale at days 3 and 7 and patient satisfaction index at day 7 post surgery. Surgery for the second site (Test/control) in the contralateral quadrants was performed 1 week after the first surgery. A higher reduction in probing depth and gain in CAL was observed in test site at 1, 3 and 6 months follow up amongst all the included participants. VAS score was lower at the test site as compared to the control sites. PSI scores were similar in both the sites. The adjunctive use of 445nm diode laser to surgical periodontal therapy contributed to improved short term clinical outcomes as assessed at the end of 6 months post- surgery. VAS score indicative of post -surgical discomfort were also lower for the laser treated sites. Hence adjunctive use of laser (445 nm wavelength) can be recommended for achieving more predictable clinical outcomes.


Assuntos
Periodontite Crônica , Humanos , Periodontite Crônica/tratamento farmacológico , Lasers Semicondutores/uso terapêutico , Resultado do Tratamento , Terapia Combinada , Raspagem Dentária
6.
J Neurosci ; 42(39): 7355-7369, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36481742

RESUMO

Interstitial collateral branching of axons is a critical component in the development of functional neural circuits. Axon collateral branches are established through a series of cellular processes initiated by the development of a specialized, focal F-actin network in axons. The formation, maintenance and remodeling of this F-actin patch is critical for the initiation of axonal protrusions that are subsequently consolidated to form a collateral branch. However, the mechanisms regulating F-actin patch dynamics are poorly understood. Fmn2 is a formin family member implicated in multiple neurodevelopmental disorders. We find that Fmn2 regulates the initiation of axon collateral protrusions in chick spinal neurons and in zebrafish motor neurons. Fmn2 localizes to the protrusion-initiating axonal F-actin patches and regulates the lifetime and size of these F-actin networks. The F-actin nucleation activity of Fmn2 is necessary for F-actin patch stability but not for initiating patch formation. We show that Fmn2 insulates the F-actin patches from disassembly by the actin-depolymerizing factor, ADF, and promotes long-lived, larger patches that are competent to initiate axonal protrusions. The regulation of axonal branching can contribute to the neurodevelopmental pathologies associated with Fmn2 and the dynamic antagonism between Fmn2 and ADF may represent a general mechanism of formin-dependent protection of Arp2/3-initiated F-actin networks from disassembly.SIGNIFICANCE STATEMENT Axonal branching is a key process in the development of functional circuits and neural plasticity. Axon collateral branching is initiated by the elaboration of F-actin filaments from discrete axonal F-actin networks. We show that the neurodevelopmental disorder-associated formin, Fmn2, is a critical regulator of axon collateral branching. Fmn2 localizes to the collateral branch-inducing F-actin patches in axons and regulates the stability of these actin networks. The F-actin nucleation activity of Fmn2 protects the patches from ADF-mediated disassembly. Opposing activities of Fmn2 and ADF exert a dynamic regulatory control on axon collateral branch initiation and may underly the neurodevelopmental defects associated with Fmn2.


Assuntos
Actinas , Peixe-Zebra , Animais , Citoesqueleto de Actina
7.
J Physiol ; 601(22): 4953-4971, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35708653

RESUMO

Extracellular vesicles (EVs) are nanoscopic packages that are heterogeneous and bona fide players in hepatic physiology and pathology as they are involved in intercellular communication. EVs carrying bioactive cargoes rich in lipids, proteins or nucleic acids are implicated in the onset and progression of liver diseases. Liver pathology using liver biopsy has been assessed for several intricate conditions such as viral hepatitis, alcoholic and non-alcoholic fatty liver disease, hepatic malignancies and drug-induced liver injury. The lacunae, however, lie in early diagnosis and timely treatment of the above conditions, underscoring the need for non-invasive, accurate diagnostic tools that could replace the gold standard method of tissue biopsy. In this regard, EVs have emerged as promising candidates that could serve as potential biomarkers. In the last two decades, EVs, owing to their multifaceted charm in bringing out cell-free therapeutic responses and the ability of their cargoes to be applied to novel biomarkers, have drawn the great attention of researchers with the advancement and clinical application of liquid biopsy. In this review, we recapitulate the role of EVs and provide insights into the promising role of these small packages as biomarkers in liver pathology.


Assuntos
Vesículas Extracelulares , Hepatopatia Gordurosa não Alcoólica , Humanos , Biomarcadores/metabolismo , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Comunicação Celular
8.
Int J Mol Sci ; 24(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36834657

RESUMO

The pathophysiology of nonalcoholic steatohepatitis (NASH) is complex, owing to its diverse pathological drivers and, until recently, there were no approved drugs for this disease. Tecomella is a popular herbal medicine used to treat hepatosplenomegaly, hepatitis, and obesity. However, the potential role of Tecomella undulata in NASH has not yet been scientifically investigated. The administration of Tecomella undulata via oral gavage lowered body weight, insulin resistance, alanine transaminase (ALT), aspartate transaminase (AST), triglycerides, and total cholesterol in western diet sugar water (WDSW) fed mice but had no effect on chow diet normal water (CDNW) fed mice. Tecomella undulata improved steatosis, lobular inflammation, and hepatocyte ballooning and resolved NASH in WDSW mice. Furthermore, Tecomella undulata also alleviated the WDSW-induced Endoplasmic Reticulum stress and oxidative stress, enhanced antioxidant status, and thus reduced inflammation in the treated mice. Of note, these effects were comparable to saroglitazar, the approved drug used to treat human NASH and the positive control used in the study. Thus, our findings indicate the potential of Tecomella undulata to ameliorate WDSW-induced steatohepatitis, and these preclinical data provide a strong rationale for assessing Tecomella undulata for the treatment of NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/patologia , Fígado/patologia , Hepatomegalia , Obesidade/patologia , Inflamação/patologia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
9.
Hepatology ; 73(4): 1290-1306, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33131062

RESUMO

BACKGROUND AND AIMS: The mechanisms by which the I148M mutant variant of the patatin-like phospholipase domain-containing 3 (PNPLA3I148M ) drives development of nonalcoholic steatohepatitis (NASH) are not known. The aim of this study was to obtain insights on mechanisms underlying PNPLA3I148M -induced acceleration of NASH. APPROACH AND RESULTS: Hepatocyte-specific overexpression of empty vector (luciferase), human wild-type PNPLA3, or PNPLA3I148M was achieved using adeno-associated virus 8 in a diet-induced mouse model of nonalcoholic fatty liver disease followed by chow diet or high-fat Western diet with ad libitum administration of sugar in drinking water (WDSW) for 8 weeks. Under WDSW, PNPLA3I148M overexpression accelerated steatohepatitis with increased steatosis, inflammation ballooning, and fibrosis (P < 0.001 versus other groups for all). Silencing PNPLA3I148M after its initial overexpression abrogated these findings. PNPLA3I148M caused 22:6n3 docosahexanoic acid depletion and increased ceramides under WDSW in addition to increasing triglycerides and diglycerides, especially enriched with unsaturated fatty acids. It also increased oxidative stress and endoplasmic reticulum stress. Increased total ceramides was associated with signature of transducer and activator of transcription 3 (STAT3) activation with downstream activation of multiple immune-inflammatory pathways at a transcriptomic level by network analyses. Silencing PNPLA3I148M reversed STAT3 activation. Conditioned media from HepG2 cells overexpressing PNPLA3I148M increased procollagen mRNA expression in LX2 cells; this was abrogated by hepatocyte STAT3 inhibition. CONCLUSIONS: Under WDSW, PNPLA3I148M overexpression promotes steatosis and NASH by metabolic reprogramming characterized by increased triglycerides and diglycerides, n3 polyunsaturated fatty acid depletion, and increased ceramides with resultant STAT3 phosphorylation and downstream inflammatory pathway activation driving increased stellate cell fibrogenic activity.


Assuntos
Lipase , Cirrose Hepática , Proteínas de Membrana , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica/efeitos adversos , Dieta Ocidental/efeitos adversos , Modelos Animais de Doenças , Progressão da Doença , Expressão Gênica , Células Hep G2 , Células Estreladas do Fígado/metabolismo , Hepatócitos/metabolismo , Humanos , Lipase/genética , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Polimorfismo Genético , Transcriptoma
10.
Allergy ; 77(6): 1873-1884, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35014049

RESUMO

BACKGROUND: Oral immunotherapy (OIT) is frequently discontinued due to adverse events (AEs) and current data suggests that lowering OIT doses can minimize severity and frequency of AEs. However, the minimum daily dose that can enable desensitization and induce immune responses in multi-food OIT (mOIT) is unknown. METHODS: Participants aged 2-25 years with multi-food allergies were pretreated with fixed-dose omalizumab (150 mg, 3 doses, every 4 weeks), and randomized 1:1 to receive mOIT to a total maintenance dose of either 300 or 1200 mg total protein, (total dose includes at least two and up to a max of five allergens) and then transitioned to real-food protein equivalents after 18 weeks of treatment. The primary endpoint was the proportion of subjects with increases in IgG4/IgE ratio of at least 2 allergens by ≥25% from baseline after 18 weeks of therapy. The primary efficacy and safety analyses were done in the intention-to-treat population. RESULTS: Sixty participants were enrolled across two sites. Seventy percent of participants in both arms showed changes in sIgG4/sIgE ratio in at least 2 allergens with no difference between the treatment groups (OR [95% CI] = 1.00 [0.29, 3.49]). Overall, there were no differences in AEs between the 300 and 1200 mg groups (19% vs. 17%, p = .69), respectively. CONCLUSIONS: Our data suggest that plasma marker changes are induced early, even at a total protein dose of 300 mg inclusive of multiple allergens when mOIT is combined with fixed-dose omalizumab. Identification of optimal mOIT dosing with adjunct omalizumab is needed for the long-term success of OIT. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03181009).


Assuntos
Dessensibilização Imunológica , Omalizumab , Administração Oral , Alérgenos , Dessensibilização Imunológica/efeitos adversos , Humanos , Imunoglobulina E , Fatores Imunológicos , Omalizumab/efeitos adversos
11.
BMC Health Serv Res ; 22(1): 1137, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076224

RESUMO

BACKGROUND: The economic burden of autism is substantial and includes a range of costs, including healthcare, education, productivity losses, informal care and respite care, among others. In India, approximately, 2 million children aged 2-9 years have autism. Given the likely substantial burden of illness and the need to identify effective and cost-effective interventions, this research aimed to produce a comprehensive cost of illness inventory (COII) suitable for children with autism in South Asia (India) to support future research. METHODS: A structured and iterative design process was followed to create the COII, including literature reviews, interviews with caregivers, pilot testing and translation. Across the development of the COII, thirty-two families were involved in the design and piloting of the tool. The COII was forward translated (from English to Hindi) and back translated. Each stage of the process of development of the COII resulted in the further refinement of the tool. RESULTS: Domains covered in the final COII include education, childcare, relocation, healthcare contacts (outpatient, inpatient, medical emergencies, investigations and medication), religious retreats and rituals, specialist equipment, workshops and training, special diet, support and care, certification, occupational adjustments and government rebates/schemes. Administration and completion of the COII determined it to be feasible to complete in 35 minutes by qualified and trained researchers. The final COII is hosted by REDCap Cloud and is a bilingual instrument (Hindi and English). CONCLUSIONS: The COII was developed using experiences gathered from an iterative process in a metropolitan area within the context of one low- and middle-income country (LMIC) setting, India. Compared to COII tools used for children with autism in high-income country settings, additional domains were required, such as complimentary medication (e.g. religious retreats and homeopathy). The COII will allow future research to quantify the cost of illness of autism in India from a broad perspective and will support relevant economic evaluations. Understanding the process of developing the questionnaire will help researchers working in LMICs needing to adapt the current COII or developing similar questionnaires.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/terapia , Criança , Efeitos Psicossociais da Doença , Humanos , Índia , Inquéritos e Questionários
12.
Lasers Med Sci ; 37(1): 103-120, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35029727

RESUMO

The literature on the efficacy of erbium lasers for nonsurgical periodontal therapy is inconsistent. The objective of the umbrella review was to collate the information available in the systematic reviews to provide a comprehensive synthesis of clinical and patient reported outcomes following the use of erbium lasers for non-surgical periodontal therapy. An electronic database search was carried out, and systematic reviews/meta-analyses which assessed the efficacy of erbium lasers as monotherapy or as an adjunct to scaling and root planing were included. The methodological quality and reporting quality of the included studies were assessed. 15 Systematic reviews/meta-analyses were obtained after title, abstract, and full text search. The meta-analyses data revealed a clinical attachment level gain, reduction in probing pocket depth at 1 and 3-month follow-up, and no additional benefit at ≥ 6-month follow-up in the erbium laser group. The evidence gap map revealed lack of clinical outcome data at > 6-month follow-up and dearth in studies assessing patient reported outcome measures and adverse events. Erbium lasers may provide short-term clinical benefits, and further studies with standardized laser parameters evaluating long-term follow-up, patient-reported outcome measures, and adverse events are needed.


Assuntos
Periodontite Crônica , Lasers de Estado Sólido , Raspagem Dentária , Érbio , Humanos , Lasers de Estado Sólido/uso terapêutico , Aplainamento Radicular , Resultado do Tratamento
13.
J Cell Physiol ; 236(5): 3383-3395, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33145763

RESUMO

Apoptosis antagonizing transcription factor (AATF), an interacting partner of RNA polymerase II is a multifunctional protein that is highly conserved in eukaryotes. In addition to the regulation of gene expression as a transcriptional coactivator, AATF is shown to play a dual role in regulating the cell cycle by displacing histone deacetylases 1 (HDAC1) from the retinoblastoma-E2F transcription factor (Rb-E2F) complex and also from the specificity protein 1 (Sp1) transcription factor responsible for p21 expression, thereby ensuring cell proliferation and growth arrest, respectively, at different checkpoints of the cell cycle. Notably, AATF has emerged as one of the most important modulators of various cellular responses such as proliferation, apoptosis, and survival. Studies have demonstrated that AATF protects cells from multiple stress stimuli such as DNA damage, ER stress, hypoxia, or glucose deprivation by inducing cell cycle arrest, autophagy, or apoptosis inhibition. Furthermore, AATF serves as a critical regulator in various cancers and promotes tumorigenesis by protecting cancer cells from apoptosis induction, favoring cell proliferation, or promoting cell survival by autophagy. Recent studies have demonstrated the key role of AATF in ribosome biosynthesis and have also provided insights into the mechanistic role of AATF, offering impressive cytoprotection in myocardial infarction, neurologic diseases, and nephronophthisis. In this review, we will provide a comprehensive overview of the role of AATF and shed light on its emerging roles underlining the potential use of AATF as a novel biomarker and as an effective therapeutic target.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Pontos de Checagem do Ciclo Celular/fisiologia , Proliferação de Células/fisiologia , Fatores de Transcrição/metabolismo , Animais , Humanos , Proteínas Repressoras/genética , Transdução de Sinais/fisiologia
14.
Allergy ; 76(5): 1463-1472, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33020913

RESUMO

BACKGROUND: Oral food challenges have demonstrated that diagnosis of almond allergy based on extract-sIgE tests displays low specificity. Molecular allergy diagnosis is expected to improve accuracy, but its value in diagnosing almond allergy remains unknown. The aim of this study was to identify relevant almond allergens and examine their ability to improve almond allergy diagnosis. METHODS: IgE-reactive proteins were purified from almond kernels. IgE binding to almond extract and the allergens was analyzed by quantitative ELISA using sera from 18 subjects with a proven almond allergy. The control group consisted of sera from 18 subjects allergic to peanut and/or tree nuts but tolerant to almond. RESULTS: Three IgE-binding proteins were identified: legumin (Pru du 6), alpha-hairpinin (Pru du 8), and mandelonitrile lyase (Pru du 10). Positive IgE (≥0.35 kU/L) to almond extract showed 94% sensitivity but only 33% specificity. IgE to Pru du 6 maintained high sensitivity (83%) and provided superior specificity (78%). Sera from almond-allergic subjects had significantly higher IgE levels to almond extract (P < .0001) and Pru du 6 (P < .0001) than sera from tolerant donors. Sensitization to Pru du 6 was highly specific for almond allergy, while frequencies of sensitization to legumins from peanut, walnut, hazelnut, and cashew were similar in both groups. IgE to Pru du 8 and Pru du 10 was less sensitive (41% and 67%), but showed specificities of 100% and 61%. CONCLUSION: The use of almond allergens markedly increases the diagnostic specificity compared to the extract. Pru du 6 is a potential new molecular marker for almond allergy.


Assuntos
Antígenos de Plantas , Hipersensibilidade Alimentar/diagnóstico , Proteínas de Plantas , Prunus dulcis , Alérgenos , Arachis , Humanos , Imunoglobulina E
15.
Hepatology ; 69(4): 1520-1534, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30394550

RESUMO

Hepatocellular carcinoma (HCC) is increasing as a cause of liver-related mortality largely because of the growing burden of nonalcoholic steatohepatitis (NASH). The mechanisms of HCC development in nonalcoholic fatty liver disease (NAFLD) are incompletely understood. We initially identified apoptosis antagonizing transcription factor (AATF) to be associated with HCC in a mouse model of NASH that develops HCC without the addition of specific carcinogens. AATF, also called che-1, is a transcriptional factor that is highly conserved among eukaryotes. AATF is known to be a central mediator of the cellular responses as it promotes cell proliferation and survival by inducing cell cycle arrest, autophagy, DNA repair, and inhibition of apoptosis. However, the role of AATF in NASH and HCC remains unknown. Here, we provide evidence for AATF as a contributory factor for HCC in NAFLD. AATF overexpression was further verified in human NASH and HCC and multiple human HCC cell lines. Tumor necrosis factor-α (TNFα), known to be increased in NASH, induced AATF expression. Promoter analysis of AATF revealed a sterol regulatory element binding transcription factor 1-c (SREBP-1c) binding site; inhibition of SREBP-1 by using specific inhibitors as well as small interfering RNA decreased TNFα-induced AATF expression. AATF interacted with signal transducer and activator of transcription 3 to increase monocyte chemoattractant protein-1 expression. AATF knockdown decreased cell proliferation, migration, invasion, colony formation, and anchorage-dependent growth in HCC cell lines. Xenograft of QGY-7703 HCC cells with AATF stably knocked down into nonobese diabetic scid gamma mice demonstrated reduced tumorigenesis and metastases. Conclusion: AATF drives NAFLD and hepatocarcinogenesis, offering a potential target for therapeutic intervention.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Proteínas Repressoras/metabolismo , Animais , Carcinoma Hepatocelular/etiologia , Quimiocina CCL2/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas/etiologia , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/complicações , Fator de Transcrição STAT3/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
16.
Mol Cell Biochem ; 471(1-2): 71-80, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32577945

RESUMO

Purification of DPP-IV enzyme from porcine serum, is presented in this study for the first time. The high molecular weight DPP-IV from porcine serum was fractioned using Sephadex G-75 gel filtration followed by DEAE Sephadex anion exchange and Sephadex G-100 gel filtration chromatography columns with a final yield of 11.25%. The SDS-PAGE of the purified sample showed a single band of molecular mass nearing 160 kDa. Distinct single band was observed after PAS staining confirmed it to be a glycoprotein. The purified enzyme showed an optimum pH and temperature of 8 and 37 °C, respectively. The enzyme effectively cleaved fluorogenic substrate Gly-Pro-AMC with Km and Vmax of 4.578 µM and 90.84 nmoles/min, respectively. Purified DPP-IV activity was inhibited by Diprotin A with an IC50 value of 8.473 µM. Among the three plant extracts used to study DPP-IV inhibition, the aqueous hot extract of Terminalia chebula showed the highest inhibition of 87.19%, followed by the aqueous cold extract of Momordica carantia, ( 31.6%) and Azadirachta indica (34.16%) at the concentration of 25 µg.


Assuntos
Dipeptídeos/metabolismo , Dipeptidil Peptidase 4/isolamento & purificação , Ensaios Enzimáticos/métodos , Oligopeptídeos/farmacologia , Animais , Dipeptidil Peptidase 4/sangue , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/farmacologia , Cinética , Peso Molecular , Especificidade por Substrato , Suínos
17.
J ECT ; 36(4): 260-264, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32453186

RESUMO

OBJECTIVE: Cognitive side effects are a common unintended outcome of electroconvulsive therapy (ECT). Routine cognitive assessment is important for monitoring patient outcomes, although it can pose challenges in busy clinical settings. Computerized cognitive testing has advantages that can facilitate routine monitoring. This study explored the construct and criterion validity of computerized cognitive testing compared with standard pen-and-paper tests for monitoring cognition in ECT patients. METHODS: The study included 24 participants with major depression who received an acute course of ECT. Cognition was assessed at pretreatment and at posttreatment with 3 computerized tests from the CogState battery (International Shopping List task, One-Card Learning, and One-Back Task) and 3 conceptually matched pen-and-paper-administered neuropsychological tests. RESULTS: At pretreatment, only performance on the computer-administered test of verbal anterograde memory (International Shopping List task) was significantly correlated with the analogous pen-and-paper measure, whereas the other computerized tests were not. Of the computerized measures, only the International Shopping List task showed significant changes from pretreatment to posttreatment (P < 0.01, Cohen d > 1.0). In contrast, all the pen-and-paper-administered tests showed significant changes from pretreatment to posttreatment (P < 0.01, Cohen d range, 0.8-1.2). Pretreatment to posttreatment cognitive changes on the computerized measures were not correlated with changes on the pen-and-paper-administered tests. CONCLUSION: Construct and criterion validity and tolerability varied between the computerized measures. The results highlighted potentially important issues related to the interpretation and utility of computerized tests in this patient population.


Assuntos
Transtornos Cognitivos/diagnóstico , Transtorno Depressivo Maior/terapia , Diagnóstico por Computador/métodos , Eletroconvulsoterapia/efeitos adversos , Testes Neuropsicológicos , Humanos , Masculino , Pessoa de Meia-Idade
18.
Hepatology ; 67(4): 1284-1302, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29083504

RESUMO

Intestinal dysbiosis is implicated in alcoholic hepatitis (AH). However, changes in the circulating microbiome, its association with the presence and severity of AH, and its functional relevance in AH is unknown. Qualitative and quantitative assessment of changes in the circulating microbiome were performed by sequencing bacterial DNA in subjects with moderate AH (MAH) (n = 18) or severe AH (SAH) (n = 19). These data were compared with heavy drinking controls (HDCs) without obvious liver disease (n = 19) and non-alcohol-consuming controls (NACs, n = 20). The data were related to endotoxin levels and markers of monocyte activation. Linear discriminant analysis effect size (LEfSe) analysis, inferred metagenomics, and predictive functional analysis using PICRUSt were performed. There was a significant increase in 16S copies/ng DNA both in MAH (P < 0.01) and SAH (P < 0.001) subjects. Compared with NACs, the relative abundance of phylum Bacteroidetes was significantly decreased in HDCs, MAH, and SAH (P < 0.001). In contrast, all alcohol-consuming groups had enrichment with Fusobacteria; this was greatest for HDCs and decreased progressively in MAH and SAH. Subjects with SAH had significantly higher endotoxemia (P = 0.01). Compared with alcohol-consuming groups, predictive functional metagenomics indicated an enrichment of bacteria with genes related to methanogenesis and denitrification. Furthermore, both HDCs and SAH showed activation of a type III secretion system that has been linked to gram-negative bacterial virulence. Metagenomics in SAH versus NACs predicted increased isoprenoid synthesis via mevalonate and anthranilate degradation, known modulators of gram-positive bacterial growth and biofilm production, respectively. CONCLUSION: Heavy alcohol consumption appears to be the primary driver of changes in the circulating microbiome associated with a shift in its inferred metabolic functions. (Hepatology 2018;67:1284-1302).


Assuntos
DNA Bacteriano/sangue , Hepatite Alcoólica/microbiologia , Hepatopatias Alcoólicas/microbiologia , Metagenômica/métodos , Microbiota/genética , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , DNA Bacteriano/genética , Endotoxinas/sangue , Feminino , Humanos , Fígado/microbiologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Monócitos/patologia
19.
Hepatology ; 67(2): 534-548, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28696585

RESUMO

The histologic spectrum of nonalcoholic fatty liver disease (NAFLD) includes fatty liver (NAFL) and steatohepatitis (NASH), which can progress to cirrhosis in up to 20% of NASH patients. Bile acids (BA) are linked to the pathogenesis and therapy of NASH. We (1) characterized the plasma BA profile in biopsy-proven NAFL and NASH and compared to controls and (2) related the plasma BA profile to liver histologic features, disease activity, and fibrosis. Liquid chromatography/mass spectrometry quantified BAs. Descriptive statistics, paired and multiple group comparisons, and regression analyses were performed. Of 86 patients (24 controls, 25 NAFL, and 37 NASH; mean age 51.8 years and body mass index 31.9 kg/m2 ), 66% were women. Increased total primary BAs and decreased secondary BAs (both P < 0.05) characterized NASH. Total conjugated primary BAs were significantly higher in NASH versus NAFL (P = 0.047) and versus controls (P < 0.0001). NASH had higher conjugated to unconjugated chenodeoxycholate (P = 0.04), cholate (P = 0.0004), and total primary BAs (P < 0.0001). The total cholate to chenodeoxycholate ratio was significantly higher in NAFLD without (P = 0.005) and with (P = 0.02) diabetes. Increased key BAs were associated with higher grades of steatosis (taurocholate), lobular (glycocholate) and portal inflammation (taurolithocholate), and hepatocyte ballooning (taurocholate). Conjugated cholate and taurocholate directly and secondary to primary BA ratio inversely correlated to NAFLD activity score. A higher ratio of total secondary to primary BA decreased (odds ratio, 0.57; P = 0.004) and higher conjugated cholate increased the likelihood of significant fibrosis (F≥2) (P = 0.007). Conclusion: NAFLD is associated with significantly altered circulating BA composition, likely unaffected by type 2 diabetes, and correlated with histological features of NASH; these observations provide the foundation for future hypothesis-driven studies of specific effects of BAs on specific aspects of NASH. (Hepatology 2018;67:534-548).


Assuntos
Ácidos e Sais Biliares/sangue , Hepatopatia Gordurosa não Alcoólica/sangue , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Receptores Citoplasmáticos e Nucleares/fisiologia , Índice de Gravidade de Doença
20.
J Hepatol ; 68(2): 230-237, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29128391

RESUMO

Non-alcoholic fatty liver disease (NAFLD) can manifest as non-alcoholic fatty liver (NAFL) or non-alcoholic steatohepatitis (NASH). NASH is often associated with progressive fibrosis which can lead to cirrhosis and hepatocellular carcinoma (HCC). NASH is increasing as an aetiology for end-stage liver disease as well as HCC. There are currently no approved therapies for NASH. A major barrier to development of therapeutics for NASH is the lack of preclinical models of disease that are appropriately validated to represent the biology and outcomes of human disease. Many in vitro and animal models have been developed. In vitro models do not fully capture the hepatic and extrahepatic milieu of human NASH and large animal models are expensive and logistically difficult to use. Therefore, there is considerable interest in the development and validation of mouse models for NAFLD, including NASH. Several models based on varying genetic or dietary manipulations have been developed. However, the majority do not recreate steatohepatitis, strictly defined as the presence of hepatocellular ballooning with or without Mallory-Denk bodies, accompanied by inflammation in the presence of macrovesicular steatosis. Others lack validation against human disease. Herein, we describe the best practices in development of mouse models of NASH. We further review existing models and the literature supporting their use as a surrogate for human disease. Finally, data on models to evaluate protective genes are discussed. It is hoped that this review will provide guidance for the interpretation of data derived from mouse models and also for the development and validation of newer models.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Hepatopatia Gordurosa não Alcoólica/terapia , Animais , Modelos Animais de Doenças , Progressão da Doença , Humanos
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