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1.
Hemasphere ; 8(6): e87, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38873532

RESUMO

Brexucabtagene autoleucel (brexu-cel) is an autologous CD19 CAR T-cell product, approved for relapsed/refractory (r/r) mantle cell lymphoma (MCL). In ZUMA-2, brexu-cel demonstrated impressive responses in patients failing ≥2 lines, including a bruton's tyrosine kinase inhibitor, with an overall and complete response rate of 93% and 67%, respectively. Here, we report our real-world intention-to-treat (ITT) outcomes for brexu-cel in consecutive, prospectively approved patients, from 12 institutions in the United Kingdom between February 2021 and June 2023, with a focus on feasibility, efficacy, and tolerability. Of 119 approved, 104 underwent leukapheresis and 83 received a brexu-cel infusion. Progressive disease (PD) and/or manufacturing (MF) were the most common reasons for failure to reach harvest and/or infusion. For infused patients, best overall and complete response rates were 87% and 81%, respectively. At a median follow-up of 13.3 months, median progression-free survival (PFS) for infused patients was 21 months (10.1-NA) with a 6- and 12-month PFS of 82% (95% confidence interval [CI], 71-89) and 62% (95% CI, 49-73), respectively. ≥Grade 3 cytokine release syndrome and neurotoxicity occurred in 12% and 22%, respectively. On multivariate analysis, inferior PFS was associated with male sex, bulky disease, ECOG PS > 1 and previous MF. Cumulative incidence of non-relapse mortality (NRM) was 6%, 15%, and 25% at 6, 12, and 24 months, respectively, and mostly attributable to infection. Outcomes for infused patients in the UK are comparable to ZUMA-2 and other real-world reports. However, ITT analysis highlights a significant dropout due to PD and/or MF. NRM events warrant further attention.

2.
Gland Surg ; 12(2): 140-151, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36915822

RESUMO

Background: Some studies suggested that the patients included in the Z0011 trial may represent patients with ultrasound-negative axillary nodes and axillary invasion diagnosed by sentinel node (SN) biopsy. Nevertheless, the National Comprehensive Cancer Network (NCCN) guidelines recommend SN mapping if 1 or 2 suspicious lymph nodes are identified on axillary ultrasound (AU). The aim of this preliminary phase of the Multimodal Targeted Axillary Surgery (MUTAS) trial was to establish the accuracy of SN mapping in patients with axillary involvement undergoing upfront surgery. Methods: Between September 2019 and March 2022, we recruited patients with biopsy-proven metastatic axillary nodes and upfront surgery from a single center. We performed SN mapping in these patients before the surgical intervention, which included axillary lymph node dissection. The biopsy-proven metastatic node, SNs and the remaining axillary nodes were excised separately. SN status was considered representative of the status of the remaining axillary nodes. We calculated the sensitivity, specificity, negative predictive value and positive predictive value of the SN, overall and in patients with palpable nodes, in those with non-palpable nodes and an AU leading to diagnosis of axillary involvement, in those with 1 or 2 suspicious nodes on AU, and in patients with a single suspicious node on AU. We evaluated clinical, imaging and pathology features as predictors of the status of the remaining axillary nodes, false-negatives, and false-positives. Results: We included 25 patients in this phase. The false-negative rate of SN mapping was 28% overall, 21.42% for patients with palpable nodes, 36.36% for patients with non-palpable nodes and an AU diagnosis of axillary involvement, 28.75% for those with 1 or 2 suspicious nodes on AU, and 15.38% in patients with a single suspicious node on AU. The negative predictive value was highest in patients with a single suspicious node on AU (75%). The only significant predictive factor was that FN showed a higher Ki67 index score. Conclusions: In this study, SN mapping was not reliable in patients with biopsy-proven metastatic axillary nodes and upfront surgery for any of the subgroups studied. Further research should elucidate the best staging pathways in these patients to avoid premature de-escalation.

4.
New Phytol ; 234(2): 412-421, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35075689

RESUMO

Damage can be signalled by extracellular ATP (eATP) using plasma membrane (PM) receptors to effect cytosolic free calcium ion ([Ca2+ ]cyt ) increase as a second messenger. The downstream PM Ca2+ channels remain enigmatic. Here, the Arabidopsis thaliana Ca2+ channel subunit CYCLIC NUCLEOTIDE-GATED CHANNEL2 (CNGC2) was identified as a critical component linking eATP receptors to downstream [Ca2+ ]cyt signalling in roots. Extracellular ATP-induced changes in single epidermal cell PM voltage and conductance were measured electrophysiologically, changes in root [Ca2+ ]cyt were measured with aequorin, and root transcriptional changes were determined by quantitative real-time PCR. Two cngc2 loss-of-function mutants were used: cngc2-3 and defence not death1 (which expresses cytosolic aequorin). Extracellular ATP-induced transient depolarization of Arabidopsis root elongation zone epidermal PM voltage was Ca2+ dependent, requiring CNGC2 but not CNGC4 (its channel co-subunit in immunity signalling). Activation of PM Ca2+ influx currents also required CNGC2. The eATP-induced [Ca2+ ]cyt increase and transcriptional response in cngc2 roots were significantly impaired. CYCLIC NUCLEOTIDE-GATED CHANNEL2 is required for eATP-induced epidermal Ca2+ influx, causing depolarization leading to [Ca2+ ]cyt increase and damage-related transcriptional response.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Trifosfato de Adenosina/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Cálcio/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/farmacologia , Células Epidérmicas , Epiderme/metabolismo , Nucleotídeos Cíclicos/metabolismo , Nucleotídeos Cíclicos/farmacologia , Transdução de Sinais
5.
Int J Mol Sci ; 21(3)2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32050714

RESUMO

Intracellular acid stress inhibits plant growth by unknown mechanisms and it occurs in acidic soils and as consequence of other stresses. In order to identify mechanisms of acid toxicity, we screened activation-tagging lines of Arabidopsis thaliana for tolerance to intracellular acidification induced by organic acids. A dominant mutant, sbt4.13-1D, was isolated twice and shown to over-express subtilase SBT4.13, a protease secreted into endoplasmic reticulum. Activity measurements and immuno-detection indicate that the mutant contains less plasma membrane H+-ATPase (PMA) than wild type, explaining the small size, electrical depolarization and decreased cytosolic pH of the mutant but not organic acid tolerance. Addition of acetic acid to wild-type plantlets induces production of ROS (Reactive Oxygen Species) measured by dichlorodihydrofluorescein diacetate. Acid-induced ROS production is greatly decreased in sbt4.13-1D and atrboh-D,F mutants. The latter is deficient in two major NADPH oxidases (NOXs) and is tolerant to organic acids. These results suggest that intracellular acidification activates NOXs and the resulting oxidative stress is important for inhibition of growth. The inhibition of acid-activated NOXs in the sbt4.13-1D mutant compensates inhibition of PMA to increase acid tolerance.


Assuntos
Germinação , Estresse Oxidativo , Prótons , Subtilisinas/genética , Arabidopsis , Proteínas de Arabidopsis/genética , Mutação , NADPH Oxidases/genética , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , Subtilisinas/metabolismo
6.
Int J Mol Sci ; 20(15)2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357380

RESUMO

One of the most important adaptations of seagrasses during sea colonization was the capacity to grow at the low micromolar nitrate concentrations present in the sea. In contrast to terrestrial plants that use H+ symporters for high-affinity NO3- uptake, seagrasses such as Zostera marina L. use a Na+-dependent high-affinity nitrate transporter. Interestingly, in the Z. marina genome, only one gene (Zosma70g00300.1; NRT2.1) is annotated to this function. Analysis of this sequence predicts the presence of 12 transmembrane domains, including the MFS domains of the NNP transporter family and the "nitrate signature" that appears in all members of the NNP family. Phylogenetic analysis shows that this sequence is more related to NRT2.5 than to NRT2.1, sharing a common ancestor with both monocot and dicot plants. Heterologous expression of ZosmaNRT2-GFP together with the high-affinity nitrate transporter accessory protein ZosmaNAR2 (Zosma63g00220.1) in Nicotiana benthamiana leaves displayed four-fold higher fluorescence intensity than single expression of ZosmaNRT2-GFP suggesting the stabilization of NRT2 by NAR2. ZosmaNRT2-GFP signal was present on the Hechtian-strands in the plasmolyzed cells, pointing that ZosmaNRT2 is localized on the plasma membrane and that would be stabilized by ZosmaNAR2. Taken together, these results suggest that Zosma70g00300.1 would encode a high-affinity nitrate transporter located at the plasma membrane, equivalent to NRT2.5 transporters. These molecular data, together with our previous electrophysiological results support that ZosmaNRT2 would have evolved to use Na+ as a driving ion, which might be an essential adaptation of seagrasses to colonize marine environments.


Assuntos
Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sódio/metabolismo , Zosteraceae/genética , Zosteraceae/metabolismo , Sequência de Aminoácidos , Proteínas de Transporte de Ânions/química , Transporte Biológico , Membrana Celular/metabolismo , Transportadores de Nitrato , Filogenia , Proteínas de Plantas/química , Estabilidade Proteica , Transporte Proteico , Relação Estrutura-Atividade , Zosteraceae/classificação
7.
J Exp Bot ; 66(3): 813-25, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25371509

RESUMO

The stress hormone abscisic acid (ABA) induces expression of defence genes in many organs, modulates ion homeostasis and metabolism in guard cells, and inhibits germination and seedling growth. Concerning the latter effect, several mutants of Arabidopsis thaliana with improved capability for H(+) efflux (wat1-1D, overexpression of AKT1 and ost2-1D) are less sensitive to inhibition by ABA than the wild type. This suggested that ABA could inhibit H(+) efflux (H(+)-ATPase) and induce cytosolic acidification as a mechanism of growth inhibition. Measurements to test this hypothesis could not be done in germinating seeds and we used roots as the most convenient system. ABA inhibited the root plasma-membrane H(+)-ATPase measured in vitro (ATP hydrolysis by isolated vesicles) and in vivo (H(+) efflux from seedling roots). This inhibition involved the core ABA signalling elements: PYR/PYL/RCAR ABA receptors, ABA-inhibited protein phosphatases (HAB1), and ABA-activated protein kinases (SnRK2.2 and SnRK2.3). Electrophysiological measurements in root epidermal cells indicated that ABA, acting through the PYR/PYL/RCAR receptors, induced membrane hyperpolarization (due to K(+) efflux through the GORK channel) and cytosolic acidification. This acidification was not observed in the wat1-1D mutant. The mechanism of inhibition of the H(+)-ATPase by ABA and its effects on cytosolic pH and membrane potential in roots were different from those in guard cells. ABA did not affect the in vivo phosphorylation level of the known activating site (penultimate threonine) of H(+)-ATPase in roots, and SnRK2.2 phosphorylated in vitro the C-terminal regulatory domain of H(+)-ATPase while the guard-cell kinase SnRK2.6/OST1 did not.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/genética , Arabidopsis/genética , Arabidopsis/metabolismo , ATPases Translocadoras de Prótons/genética , Proteínas de Arabidopsis/metabolismo , Membrana Celular/metabolismo , Cloretos/metabolismo , Citosol/metabolismo , Íons/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Potássio/metabolismo , ATPases Translocadoras de Prótons/metabolismo
8.
Plant J ; 70(4): 704-16, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22268595

RESUMO

Intracellular pH must be kept close to neutrality to be compatible with cellular functions, but the mechanisms of pH homeostasis and the responses to intracellular acidification are mostly unknown. In the plant Arabidopsis thaliana, we found that intracellular acid stress generated by weak organic acids at normal external pH induces expression of several chaperone genes, including ROF2, which encodes a peptidyl-prolyl cis-trans isomerase of the FK506-binding protein class. Loss of function of ROF2, and especially double mutation of ROF2 and the closely related gene ROF1, results in acid sensitivity. Over-expression of ROF2 confers tolerance to intracellular acidification by increasing proton extrusion from cells. The activation of the plasma membrane proton pump (H(+) -ATPase) is indirect: over-expression of ROF2 activates K(+) uptake, causing depolarization of the plasma membrane, which activates the electrogenic H(+) pump. The depolarization of ROF2 over-expressing plants explains their tolerance to toxic cations such as lithium, norspermidine and hygromycin B, whose uptake is driven by the membrane potential. As ROF2 induction and intracellular acidification are common consequences of many stresses, this mechanism of pH homeostasis may be of general importance for stress tolerance.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Homeostase , Peptidilprolil Isomerase/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Membrana Celular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Espaço Intracelular/química , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Peptidilprolil Isomerase/metabolismo , Plantas Geneticamente Modificadas , Potássio/metabolismo , ATPases Translocadoras de Prótons/metabolismo , Prótons , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rubídio/metabolismo , Transcriptoma
9.
Plant J ; 58(6): 903-13, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19220789

RESUMO

Extracellular ATP regulates higher plant growth and adaptation. The signalling events may be unique to higher plants, as they lack animal purinoceptor homologues. Although it is known that plant cytosolic free Ca2+ can be elevated by extracellular ATP, the mechanism is unknown. Here, we have studied roots of Arabidopsis thaliana to determine the events that lead to the transcriptional stress response evoked by extracellular ATP. Root cell protoplasts were used to demonstrate that signalling to elevate cytosolic free Ca2+ is determined by ATP perception at the plasma membrane, and not at the cell wall. Imaging revealed that extracellular ATP causes the production of reactive oxygen species in intact roots, with the plasma membrane NADPH oxidase AtRBOHC being the major contributor. This resulted in the stimulation of plasma membrane Ca2+-permeable channels (determined using patch-clamp electrophysiology), which contribute to the elevation of cytosolic free Ca2+. Disruption of this pathway in the AtrbohC mutant impaired the extracellular ATP-induced increase in reactive oxygen species (ROS), the activation of Ca2+ channels, and the transcription of the MAP kinase3 gene that is known to be involved in stress responses. This study shows that higher plants, although bereft of purinoceptor homologues, could have evolved a distinct mechanism to transduce the ATP signal at the plasma membrane.


Assuntos
Trifosfato de Adenosina/metabolismo , Arabidopsis/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio , NADPH Oxidases/metabolismo , Proteínas de Arabidopsis/metabolismo , Cálcio/metabolismo , Membrana Celular/metabolismo , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
10.
J Periodontol ; 79(7): 1297-303, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18597614

RESUMO

BACKGROUND: Wegener's granulomatosis (WG) is a complex disease, characterized by a necrotizing vasculitis that usually involves the upper airways, lungs, and kidneys; occasionally, other organs may also be affected. Because of the severity and rapid progression of the disease, early diagnosis and treatment are critical; this type of vasculitis is potentially fatal if left unchecked. METHODS: A 64-year-old woman presented with a chief complaint of a gingival mass that had appeared 2 months before and had grown rapidly. In the previous months she complained of malaise without weight loss. An intraoral examination revealed the presence of a solitary gingival mass, 2 cm in diameter, affecting the area above the upper central incisors. The lesion displayed a granular, erythematous, speckled surface with petechiae, characteristic of WG. RESULTS: A biopsy of the lesion, a thoracic computed tomography, and the presence of high titers of antineutrophil cytoplasmic antibodies (ANCA) in the blood established the diagnosis of WG. An initial combination therapy of prednisone and cyclophosphamide successfully abated most of the patient's symptoms. CONCLUSIONS: The occurrence of an extremely rare tumor-like form of strawberry gingiva was the primary clinical sign that led to a diagnosis of WG. This case emphasizes the important role of the dentist in the diagnosis of this potentially fatal disease.


Assuntos
Doenças da Gengiva/diagnóstico , Granulomatose com Poliangiite/diagnóstico , Anticorpos Anticitoplasma de Neutrófilos/análise , Biópsia , Diagnóstico Diferencial , Eritema/diagnóstico , Feminino , Neoplasias Gengivais/diagnóstico , Humanos , Pessoa de Meia-Idade , Púrpura/diagnóstico
11.
Autophagy ; 3(4): 366-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17438367

RESUMO

Paraquat (PQ) (1, 1'-dimethyl-4, 4'-bipyridinium dichloride), a widely used herbicide, has been suggested as a potential etiologic factor for the development of Parkinson's disease (PD). In neurons from patients with PD display characteristics of autophagy, a degradative mechanism involved in the recycling and turnover of cytoplasmic constituents from eukaryotic cells. Low concentrations of paraquat have been recently found to induce autophagy in human neuroblastoma cells, and ultimately the neurons succumb to apoptotic death. Whereas caspase inhibition retarded cell death, autophagy inhibition accelerated the apoptotic cell death induced by paraquat. These findings suggest a relationship between autophagy and apoptotic cell death in human neuroblastoma cells treated with paraquat and open a new line of investigation to advance our knowledge regarding the origin of PD.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Herbicidas/toxicidade , Neurônios/efeitos dos fármacos , Paraquat/toxicidade , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Humanos , Modelos Biológicos , Neuroblastoma/patologia
12.
Toxicol Sci ; 97(2): 448-58, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17341480

RESUMO

Autophagy is a degradative mechanism involved in the recycling and turnover of cytoplasmic constituents from eukaryotic cells. This phenomenon of autophagy has been observed in neurons from patients with Parkinson's disease (PD), suggesting a functional role for autophagy in neuronal cell death. On the other hand, it has been demonstrated that exposure to pesticides can be a risk factor in the incidence of PD. In this sense, paraquat (PQ) (1,1'-dimethyl-4,4'-bipyridinium dichloride), a widely used herbicide that is structurally similar to the known dopaminergic neurotoxicant MPP(+) (1-methyl-4-phenyl-pyridine), has been suggested as a potential etiologic factor for the development of PD. The current study shows, for the first time, that low concentrations of PQ induce several characteristics of autophagy in human neuroblastoma SH-SY5Y cells. In this way, PQ induced the accumulation of autophagic vacuoles (AVs) in the cytoplasm and the recruitment of a LC3-GFP fusion protein to AVs. Furthermore, the cells treated with PQ showed an increase of the long-lived protein degradation which is blocked in the presence of the autophagy inhibitor 3-methyladenine and regulated by the mammalian target of rapamycin (mTOR) signaling. Finally, the cells succumbed to cell death with hallmarks of apoptosis such as phosphatidylserine exposure, caspase activation, and chromatin condensation. While caspase inhibition retarded cell death, autophagy inhibition accelerated the apoptotic cell death induced by PQ. Altogether, these findings show the relationship between autophagy and apoptotic cell death in human neuroblastoma cells treated with PQ.


Assuntos
Autofagia/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Herbicidas/toxicidade , Neuroblastoma/patologia , Paraquat/toxicidade , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Citometria de Fluxo , Imunofluorescência , Humanos , Indicadores e Reagentes , Microscopia Eletrônica , Proteínas de Neoplasias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transfecção
13.
Hum Exp Toxicol ; 24(9): 475-80, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16235737

RESUMO

Paraquat (PQ) is a known herbicide that causes acute cell injury by undergoing redox cycling. In previous reports, it has been reported that melatonin reduces PQ-induced hepatic toxicity in vivo, but, at the moment, there is no evidence that this effect occurs in this organ in vitro. In the present study we examined the effect of melatonin on PQ-induced oxidative damage in the liver using a hepatocyte suspension as a biological model. Preincubation of hepatocytes with melatonin (0.5, 1 or 2 mM), 30 min prior to PQ (10 mM) addition, prevented in a dose-and time-dependent manner the loss of viability, the leakage of lactate dehydrogenase, depletion of intracellular glutathione and malondialdehyde accumulation induced by the herbicide. Melatonin at the highest dose assayed (2 mM) completely prevented cell damage caused by PQ. These effects of melatonin are similar to those described in studies carried out in vivo. These results confirm that melatonin confers protection against PQ-induced hepatic oxidative stress and show that freshly isolated hepatocyte suspension is an adequate in vitro system for evaluating the cytoprotective effects of melatonin on oxidative injury caused by xenobiotics.


Assuntos
Antioxidantes/farmacologia , Hepatócitos/efeitos dos fármacos , Melatonina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Hepatócitos/metabolismo , Herbicidas , Técnicas In Vitro , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Paraquat , Ratos , Ratos Wistar , Fatores de Tempo
15.
Rev. cuba. oftalmol ; 3(1): 30-4, ene.-abr. 1990. ilus
Artigo em Espanhol | LILACS | ID: lil-91532

RESUMO

Se hace la presentación de 4 pacientes denominadas que padecen la forma benigna de oftalmopatía de Graves Basedow. Se señala su mejoría con la normalización de la función tiroidea y se hace breve revisión del tema


Assuntos
Criança , Adolescente , Humanos , Feminino , Doença de Graves
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