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1.
ESMO Open ; 8(3): 101570, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37230028

RESUMO

BACKGROUND: The clinical relevance of promoter mutations and single nucleotide polymorphism rs2853669 of telomerase reverse transcriptase (TERT) and telomere length in patients with isocitrate dehydrogenase (IDH) wild-type glioblastoma (GBM) patients remains unclear. Moreover, some studies speculated that TERT promoter status might influence the prognostic role of O6-methylguanine DNA methyltransferase (MGMT) promoter methylation in newly diagnosed GBM. We carried out a large study to investigate their clinical impact and their interaction in newly diagnosed GBM patients. PATIENTS AND METHODS: We included 273 newly diagnosed IDH wild-type GBM patients who started treatment at Veneto Institute of Oncology IOV - IRCCS (Padua, Italy) from December 2016 to January 2020. TERT promoter mutations (-124 C>T and -146 C>T) and SNP rs2853669 (-245 T>C), relative telomere length (RTL) and MGMT methylation status were retrospectively assessed in this prospective cohort of patients. RESULTS: Median overall survival (OS) of 273 newly diagnosed IDH wild-type GBM patients was 15 months. TERT promoter was mutated in 80.2% of patients, and most had the rs2853669 single nucleotide polymorphism as T/T genotype (46.2%). Median RTL was 1.57 (interquartile range 1.13-2.32). MGMT promoter was methylated in 53.4% of cases. At multivariable analysis, RTL and TERT promoter mutations were not associated with OS or progression-free survival (PFS). Notably, patients C carrier of rs2853669 (C/C+C/T genotypes) showed a better PFS compared with those with the T/T genotype (hazard ratio 0.69, P = 0.007). In terms of OS and PFS, all interactions between MGMT, TERT and RTL and between TERT and rs2853669 genotype were not statistically significant. CONCLUSIONS: Our findings suggest the presence of the C variant allele at the rs2853669 of the TERT promoter as an attractive independent prognostic biomarker of disease progression in IDH wild-type GBM patients. RTL and TERT promoter mutational status were not correlated to survival regardless of MGMT methylation status.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Telomerase , Humanos , Prognóstico , Glioblastoma/genética , Isocitrato Desidrogenase/genética , Estudos Retrospectivos , Metilação , Estudos Prospectivos , Neoplasias Encefálicas/diagnóstico , Telômero , Telomerase/genética , Metilases de Modificação do DNA/genética , Proteínas Supressoras de Tumor/genética , Enzimas Reparadoras do DNA/genética
2.
Mol Psychiatry ; 22(8): 1096-1109, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28584287

RESUMO

CACNA1C, encoding the Cav1.2 subunit of L-type Ca2+ channels, has emerged as one of the most prominent and highly replicable susceptibility genes for several neuropsychiatric disorders. Cav1.2 channels play a crucial role in calcium-mediated processes involved in brain development and neuronal function. Within the CACNA1C gene, disease-associated single-nucleotide polymorphisms have been associated with impaired social and cognitive processing and altered prefrontal cortical (PFC) structure and activity. These findings suggest that aberrant Cav1.2 signaling may contribute to neuropsychiatric-related disease symptoms via impaired PFC function. Here, we show that mice harboring loss of cacna1c in excitatory glutamatergic neurons of the forebrain (fbKO) that we have previously reported to exhibit anxiety-like behavior, displayed a social behavioral deficit and impaired learning and memory. Furthermore, focal knockdown of cacna1c in the adult PFC recapitulated the social deficit and elevated anxiety-like behavior, but not the deficits in learning and memory. Electrophysiological and molecular studies in the PFC of cacna1c fbKO mice revealed higher E/I ratio in layer 5 pyramidal neurons and lower general protein synthesis. This was concurrent with reduced activity of mTORC1 and its downstream mRNA translation initiation factors eIF4B and 4EBP1, as well as elevated phosphorylation of eIF2α, an inhibitor of mRNA translation. Remarkably, systemic treatment with ISRIB, a small molecule inhibitor that suppresses the effects of phosphorylated eIF2α on mRNA translation, was sufficient to reverse the social deficit and elevated anxiety-like behavior in adult cacna1c fbKO mice. ISRIB additionally normalized the lower protein synthesis and higher E/I ratio in the PFC. Thus this study identifies a novel Cav1.2 mechanism in neuropsychiatric-related endophenotypes and a potential future therapeutic target to explore.


Assuntos
Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Animais , Ansiedade , Comportamento Animal/efeitos dos fármacos , Cálcio/metabolismo , Canais de Cálcio Tipo L/genética , Modelos Animais de Doenças , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Fatores de Iniciação em Eucariotos/genética , Fatores de Iniciação em Eucariotos/metabolismo , Predisposição Genética para Doença/genética , Hipocampo/metabolismo , Humanos , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Prosencéfalo/metabolismo , Células Piramidais/metabolismo , Comportamento Social
3.
Nutr Metab Cardiovasc Dis ; 27(6): 552-563, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28511903

RESUMO

BACKGROUND AND AIMS: Oxidized LDL (oxLDL) or pro-inflammatory stimuli lead to increased oxidative stress linked to endothelial dysfunction and atherosclerosis. The oxLDL receptor-1 (LOX1) is elevated within atheromas and cholesterol-lowering statins inhibit LOX1 expression. Berberine (BBR), an alkaloid extracted from plants of gender Berberis, has lipid-lowering and anti-inflammatory activity. However, its role in regulating LOX1-mediated signaling is still unknown. The aim of this study was to investigate the effect of BBR on oxLDL- and TNFα-induced endothelial dysfunction in human umbilical vein endothelial cells (HUVECs) and to compare it with that of lovastatin (LOVA). METHODS AND RESULTS: Cytotoxicity was determined by lactate dehydrogenase assay. Antioxidant capacity was measured with chemiluminescent and fluorescent method and intracellular ROS levels through a fluorescent dye. Gene and protein expression levels were assayed by qRT-PCR and western blot, respectively. HUVECs exposure to oxLDL (30 µg/ml) or TNFα (10 ng/ml) for 24 h led to a significant increase in LOX1 expression, effect abrogated by BBR (5 µM) and LOVA (5 µM). BBR but not LOVA treatment abolished the TNFα-induced cytotoxicity and restored the activation of Akt signaling. In spite of a low direct antioxidant capacity, both compounds reduced intracellular ROS levels generated by treatment of TNFα but only BBR inhibited NOX2 expression, MAPK/Erk1/2 signaling and subsequent NF-κB target genes VCAM and ICAM expression, induced by TNFα. CONCLUSIONS: These findings demonstrated for the first time that BBR could prevent the oxLDL and TNFα - induced LOX1 expression and oxidative stress, key events that lead to NOX, MAPK/Erk1/2 and NF-κB activation linked to endothelial dysfunction. CHEMICAL COMPOUNDS STUDIED IN THIS ARTICLE: Berberine (PubChem CID: 2353); Lovastatin (PubChem CID: 53232).


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Berberina/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Lipoproteínas LDL/farmacologia , Lovastatina/farmacologia , Receptores Depuradores Classe E/agonistas , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citoproteção , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Glicoproteínas de Membrana/metabolismo , NADPH Oxidase 2 , NADPH Oxidases/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptores Depuradores Classe E/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia
4.
Int J Immunopathol Pharmacol ; 24(2): 523-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21658329

RESUMO

Keratosis pilaris (KP) is a follicular hyperkeratosis disorder which is frequently detected in the adult population (44%), mostly in female adolescents (80%). It is a genetic autodominant dermatosis with variable penetrance, but no specific gene association has been determined, even though association to the presence of chromosome 18p deletion has been reported in some cases. We report the case of a 51-year-old Caucasian woman affected by keratosis pilaris gradually progressing with age and with a story of multiple abortions. Standard karyotype and CGH array analyses did not reveal any genetic abnormality. Virological analyses detected the presence of HPV 36 DNA inside the dorsum biopsy, leading to hypothesize its involvement in the evolution of the lesion. Clinical history and patient examination led the diagnosis of an idiopathic case of Ulerythema ophryogenes. The analysis of more cases could be useful to verify the involvement of cutaneous HPV in the progression of the clinical manifestation of the KP variants.


Assuntos
Erros de Diagnóstico/prevenção & controle , Pele/patologia , Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Anormalidades Múltiplas/patologia , Anormalidades Múltiplas/virologia , Aborto Espontâneo/genética , Sequência de Bases , Biópsia , Hibridização Genômica Comparativa , DNA Viral/análise , Doença de Darier , Sobrancelhas/anormalidades , Sobrancelhas/patologia , Sobrancelhas/virologia , Feminino , Humanos , Cariotipagem , Ceratose/diagnóstico , Ceratose/genética , Ceratose/patologia , Ceratose/virologia , Pessoa de Meia-Idade , Dados de Sequência Molecular , Papillomaviridae/genética , Valor Preditivo dos Testes , Pele/virologia , Natimorto/genética
5.
Int J Immunopathol Pharmacol ; 24(1): 217-23, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21496405

RESUMO

The aim of this study is to monitor type I interferon (IFN) activation in the cervical mucosa of Human Papillomavirus (HPV)-infected and uninfected women attending a routine gynaecologic clinic. The expression of three IFN-induced genes (MxA coding for human Mixovirus resistance protein A, ISG15 Interferon Stimulated Gene coding for a 15 kDa ubiquitin-like protein and UBP43 coding for the ISG15 isopeptidase) was determined as the mRNA copy number in cervical cells, normalized to the mRNA ones of the beta-glucuronidase gene. Type-specific HPV-DNA load was concurrently determined in the HPV-positive samples. Out of 127 samples tested, 54 were sufficient for both DNA and RNA extraction. The type-specific HPV-DNA copy numbers in the 34 HPV-positive samples varied widely. No significant association was found between copy numbers of MxA, ISG15, UBP43 and HPV status or viral load. However, despite a marked inter-individual variability, ISG15 expression was significantly higher when low-risk HPV infections were compared with HPV-negative samples, while high-risk HPV infections had very low ISG15 levels. The lack of ISG15 activation in high-risk HPV-infected cervical cells could be due to the lack of p53-mediated induction or to HPV-directed specific inhibition of type I IFN pathways. This study approach might be of value in clarifying the role of type I IFN activation in determining the clearance or persistence of HPV infections.


Assuntos
Colo do Útero/imunologia , Interferon Tipo I/fisiologia , Mucosa/imunologia , Infecções por Papillomavirus/imunologia , Adolescente , Adulto , Colo do Útero/virologia , Citocinas/genética , DNA Viral/análise , Endopeptidases/genética , Feminino , Proteínas de Ligação ao GTP/genética , Regulação da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Mucosa/virologia , Proteínas de Resistência a Myxovirus , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , RNA Mensageiro/análise , Ubiquitina Tiolesterase , Ubiquitinas/genética , Carga Viral
6.
Phys Rev Lett ; 100(15): 152502, 2008 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-18518100

RESUMO

The neutron unbound ground state of (25)O (Z=8, N=17) was observed for the first time in a proton knockout reaction from a (26)F beam. A single resonance was found in the invariant mass spectrum corresponding to a neutron decay energy of 770_+20(-10) keV with a total width of 172(30) keV. The N=16 shell gap was established to be 4.86(13) MeV by the energy difference between the nu1s(1/2) and nu0d(3/2) orbitals. The neutron separation energies for (25)O agree with the calculations of the universal sd shell model interaction. This interaction incorrectly predicts an (26)O ground state that is bound to two-neutron decay by 1 MeV, leading to a discrepancy between the theoretical calculations and experiment as to the particle stability of (26)O. The observed decay width was found to be on the order of a factor of 2 larger than the calculated single-particle width using a Woods-Saxon potential.

7.
J Chromatogr B Biomed Sci Appl ; 759(1): 27-32, 2001 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-11499626

RESUMO

Clenbuterol molecularly imprinted polymers (MIPs) as chromatographic stationary phase for the solid-phase extraction (SPE) of the drug from biological samples have been prepared. Propylene columns filled with 500 mg of clenbuterol MIPs have been tested with respect to their loading capacity, memory effects, selectivity toward related drugs (mabuterol, clenproperol, clenisopenterol, ritodrine) and specificity toward interferences arising from heterogeneous matrices such as animal feeds, bovine urine and liver. Analytes were concentrated on Extrelut 20 columns and the residues resuspended in 70% acetonitrile. Application, washing and elution fractions were collected and analyzed by HPLC-diode array detection. Results indicate this MIP approach in SPE is extremely selective for clenbuterol, mabuterol, clenproperol and clenisopenterol (>95% found in the eluate), with a loading capacity of about 20 microg/100 mg of stationary phase. Ritodrine showed a recovery rate of 51%. The molecular recognition mechanism is so specific to allow clenbuterol detection and identification by conventional detectors at level of interest (ppb) also from complex matrices such as feeds, urine and liver.


Assuntos
Agonistas Adrenérgicos beta/isolamento & purificação , Ração Animal/análise , Cromatografia Líquida de Alta Pressão/métodos , Clembuterol/isolamento & purificação , Substâncias de Crescimento/isolamento & purificação , Polímeros/química , Animais , Bovinos , Espectrofotometria Ultravioleta
8.
Science ; 287(5460): 2004-6, 2000 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-10720324

RESUMO

The effects of increasing carbon dioxide (CO2) and climate on net carbon storage in terrestrial ecosystems of the conterminous United States for the period 1895-1993 were modeled with new, detailed historical climate information. For the period 1980-1993, results from an ensemble of three models agree within 25%, simulating a land carbon sink from CO2 and climate effects of 0.08 gigaton of carbon per year. The best estimates of the total sink from inventory data are about three times larger, suggesting that processes such as regrowth on abandoned agricultural land or in forests harvested before 1980 have effects as large as or larger than the direct effects of CO2 and climate. The modeled sink varies by about 100% from year to year as a result of climate variability.


Assuntos
Dióxido de Carbono/metabolismo , Carbono/metabolismo , Clima , Ecossistema , Agricultura , Atmosfera , Simulação por Computador , Geografia , Árvores , Estados Unidos
9.
Proc Natl Acad Sci U S A ; 95(5): 2216-21, 1998 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-9482865

RESUMO

Germacrene C was found by GC-MS and NMR analysis to be the most abundant sesquiterpene in the leaf oil of Lycopersicon esculentum cv. VFNT Cherry, with lesser amounts of germacrene A, guaia-6,9-diene, germacrene B, beta-caryophyllene, alpha-humulene, and germacrene D. Soluble enzyme preparations from leaves catalyzed the divalent metal ion-dependent cyclization of [1-3H]farnesyl diphosphate to these same sesquiterpene olefins, as determined by radio-GC. To obtain a germacrene synthase cDNA, a set of degenerate primers was constructed based on conserved amino acid sequences of related terpenoid cyclases. With cDNA prepared from leaf epidermis-enriched mRNA, these primers amplified a 767-bp fragment that was used as a hybridization probe to screen the cDNA library. Thirty-one clones were evaluated for functional expression of terpenoid cyclase activity in Escherichia coli by using labeled geranyl, farnesyl, and geranylgeranyl diphosphates as substrates. Nine cDNA isolates expressed sesquiterpene synthase activity, and GC-MS analysis of the products identified germacrene C with smaller amounts of germacrene A, B, and D. None of the expressed proteins was active with geranylgeranyl diphosphate; however, one truncated protein converted geranyl diphosphate to the monoterpene limonene. The cDNA inserts specify a deduced polypeptide of 548 amino acids (Mr = 64,114), and sequence comparison with other plant sesquiterpene cyclases indicates that germacrene C synthase most closely resembles cotton delta-cadinene synthase (50% identity).


Assuntos
Alquil e Aril Transferases/biossíntese , Carbono-Carbono Liases/biossíntese , Solanum lycopersicum/enzimologia , Alquil e Aril Transferases/química , Alquil e Aril Transferases/isolamento & purificação , Sequência de Aminoácidos , Carbono-Carbono Liases/química , Carbono-Carbono Liases/isolamento & purificação , Clonagem Molecular , Sequência Conservada , Primers do DNA , Escherichia coli , Dados de Sequência Molecular , Óleos de Plantas , Fosfatos de Poli-Isoprenil/metabolismo , Reação em Cadeia da Polimerase , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Sesquiterpenos/química , Sesquiterpenos/metabolismo
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