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1.
Cell ; 184(25): 6067-6080.e13, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34852238

RESUMEN

The human monoclonal antibody (HmAb) C10 potently cross-neutralizes Zika virus (ZIKV) and dengue virus. Analysis of antibody fragment (Fab) C10 interactions with ZIKV and dengue virus serotype 2 (DENV2) particles by cryoelectron microscopy (cryo-EM) and amide hydrogen/deuterium exchange mass spectrometry (HDXMS) shows that Fab C10 binding decreases overall ZIKV particle dynamics, whereas with DENV2, the same Fab causes increased dynamics. Testing of different Fab C10:DENV2 E protein molar ratios revealed that, at higher Fab ratios, especially at saturated concentrations, the Fab enhanced viral dynamics (detected by HDXMS), and observation under cryo-EM showed increased numbers of distorted particles. Our results suggest that Fab C10 stabilizes ZIKV but that with DENV2 particles, high Fab C10 occupancy promotes E protein dimer conformational changes leading to overall increased particle dynamics and distortion of the viral surface. This is the first instance of a broadly neutralizing antibody eliciting virus-specific increases in whole virus particle dynamics.


Asunto(s)
Anticuerpos Neutralizantes , Virus del Dengue , Dengue , Proteínas del Envoltorio Viral , Infección por el Virus Zika , Virus Zika , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/metabolismo , Anticuerpos Antivirales/inmunología , Reacciones Cruzadas , Dengue/inmunología , Dengue/virología , Virus del Dengue/inmunología , Virus del Dengue/fisiología , Humanos , Unión Proteica , Proteínas del Envoltorio Viral/química , Proteínas del Envoltorio Viral/inmunología , Proteínas del Envoltorio Viral/metabolismo , Virus Zika/inmunología , Virus Zika/fisiología , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/virología
2.
CA Cancer J Clin ; 70(4): 299-312, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32478924

RESUMEN

Glioblastoma is the most common malignant primary brain tumor. Overall, the prognosis for patients with this disease is poor, with a median survival of <2 years. There is a slight predominance in males, and incidence increases with age. The standard approach to therapy in the newly diagnosed setting includes surgery followed by concurrent radiotherapy with temozolomide and further adjuvant temozolomide. Tumor-treating fields, delivering low-intensity alternating electric fields, can also be given concurrently with adjuvant temozolomide. At recurrence, there is no standard of care; however, surgery, radiotherapy, and systemic therapy with chemotherapy or bevacizumab are all potential options, depending on the patient's circumstances. Supportive and palliative care remain important considerations throughout the disease course in the multimodality approach to management. The recently revised classification of glioblastoma based on molecular profiling, notably isocitrate dehydrogenase (IDH) mutation status, is a result of enhanced understanding of the underlying pathogenesis of disease. There is a clear need for better therapeutic options, and there have been substantial efforts exploring immunotherapy and precision oncology approaches. In contrast to other solid tumors, however, biological factors, such as the blood-brain barrier and the unique tumor and immune microenvironment, represent significant challenges in the development of novel therapies. Innovative clinical trial designs with biomarker-enrichment strategies are needed to ultimately improve the outcome of patients with glioblastoma.


Asunto(s)
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Recurrencia Local de Neoplasia/epidemiología , Antineoplásicos/uso terapéutico , Bevacizumab/uso terapéutico , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/cirugía , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Quimioradioterapia Adyuvante/métodos , Glioblastoma/genética , Glioblastoma/mortalidad , Glioblastoma/patología , Humanos , Inmunoterapia/métodos , Incidencia , Isocitrato Deshidrogenasa/genética , Magnetoterapia/métodos , Imagen por Resonancia Magnética , Mutación , Recurrencia Local de Neoplasia/prevención & control , Medicina de Precisión/métodos , Pronóstico , Literatura de Revisión como Asunto , Tasa de Supervivencia , Temozolomida/uso terapéutico , Resultado del Tratamiento , Microambiente Tumoral , Estados Unidos/epidemiología
3.
Proc Natl Acad Sci U S A ; 120(18): e2220545120, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37094124

RESUMEN

The HIV-1 capsid houses the viral genome and interacts extensively with host cell proteins throughout the viral life cycle. It is composed of capsid protein (CA), which assembles into a conical fullerene lattice composed of roughly 200 CA hexamers and 12 CA pentamers. Previous structural analyses of individual CA hexamers and pentamers have provided valuable insight into capsid structure and function, but detailed structural information about these assemblies in the broader context of the capsid lattice is lacking. In this study, we combined cryoelectron tomography and single particle analysis (SPA) cryoelectron microscopy to determine structures of continuous regions of the capsid lattice containing both hexamers and pentamers. We also developed a method of liposome scaffold-based in vitro lattice assembly ("lattice templating") that enabled us to directly study the lattice under a wider range of conditions than has previously been possible. Using this approach, we identified a critical role for inositol hexakisphosphate in pentamer formation and determined the structure of the CA lattice bound to the capsid-targeting antiretroviral drug GS-6207 (lenacapavir). Our work reveals key structural details of the mature HIV-1 CA lattice and establishes the combination of lattice templating and SPA as a robust strategy for studying retroviral capsid structure and capsid interactions with host proteins and antiviral compounds.


Asunto(s)
Proteínas de la Cápside , VIH-1 , Proteínas de la Cápside/química , Cápside/metabolismo , VIH-1/metabolismo , Microscopía por Crioelectrón/métodos , Ensamble de Virus
4.
Proc Natl Acad Sci U S A ; 120(16): e2220557120, 2023 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-37040417

RESUMEN

The mature HIV-1 capsid protects the viral genome and interacts with host proteins to travel from the cell periphery into the nucleus. To achieve this, the capsid protein, CA, constructs conical capsids from a lattice of hexamers and pentamers, and engages in and then relinquishes multiple interactions with cellular proteins in an orchestrated fashion. Cellular host factors including Nup153, CPSF6, and Sec24C engage the same pocket within CA hexamers. How CA assembles pentamers and hexamers of different curvatures, how CA oligomerization states or curvature might modulate host-protein interactions, and how binding of multiple cofactors to a single site is coordinated, all remain to be elucidated. Here, using single-particle cryoEM, we have determined the structure of the mature HIV-1 CA pentamer and hexamer from conical CA-IP6 polyhedra to ~3 Å resolution. We also determined structures of hexamers in the context of multiple lattice curvatures and number of pentamer contacts. Comparison of these structures, bound or not to host protein peptides, revealed two structural switches within HIV-1 CA that modulate peptide binding according to CA lattice curvature and whether CA is hexameric or pentameric. These observations suggest that the conical HIV-1 capsid has different host-protein binding properties at different positions on its surface, which may facilitate cell entry and represent an evolutionary advantage of conical morphology.


Asunto(s)
Cápside , VIH-1 , Cápside/metabolismo , Proteínas de la Cápside/química , VIH-1/genética , Unión Proteica , Citoplasma/metabolismo
5.
Cancer ; 130(10): 1758-1765, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38422026

RESUMEN

BACKGROUND: In early-stage non-small cell lung cancer (NSCLC), recurrence is frequently observed. Circulating tumor DNA (ctDNA) has emerged as a noninvasive tool to risk stratify patients for recurrence after curative intent therapy. This study aimed to risk stratify patients with early-stage NSCLC via a personalized, tumor-informed multiplex polymerase chain reaction (mPCR) next-generation sequencing assay. METHODS: This retrospective cohort study included patients with stage I-III NSCLC. Recruited patients received standard-of-care management (surgical resection with or without adjuvant chemotherapy, followed by surveillance). Whole-exome sequencing of NSCLC resected tissue and matched germline DNA was used to design patient-specific mPCR assays (Signatera, Natera, Inc) to track up to 16 single-nucleotide variants in plasma samples. RESULTS: The overall cohort with analyzed plasma samples consisted of 57 patients. Stage distribution was 68% for stage I and 16% each for stages II and III. Presurgery (i.e., at baseline), ctDNA was detected in 15 of 57 patients (26%). ctDNA detection presurgery was significantly associated with shorter recurrence-free survival (RFS; hazard ratio [HR], 3.54; 95% confidence interval [CI], 1.00-12.62; p = .009). In the postsurgery setting, ctDNA was detected in seven patients, of whom 100% experienced radiological recurrence. ctDNA positivity preceded radiological findings by a median lead time of 2.8 months (range, 0-12.9 months). Longitudinally, ctDNA detection at any time point was associated with shorter RFS (HR, 16.1; 95% CI, 1.63-158.9; p < .0001). CONCLUSIONS: ctDNA detection before surgical resection was strongly associated with a high risk of relapse in early-stage NSCLC in a large unique Asian cohort. Prospective studies are needed to assess the clinical utility of ctDNA status in this setting.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , ADN Tumoral Circulante , Secuenciación de Nucleótidos de Alto Rendimiento , Neoplasias Pulmonares , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Neoplasia Residual , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/patología , Masculino , ADN Tumoral Circulante/sangre , ADN Tumoral Circulante/genética , Femenino , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/sangre , Carcinoma de Pulmón de Células no Pequeñas/patología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Neoplasia Residual/genética , Neoplasia Residual/diagnóstico , Detección Precoz del Cáncer/métodos , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/sangre , Adulto , Anciano de 80 o más Años , Reacción en Cadena de la Polimerasa Multiplex/métodos
6.
Proc Natl Acad Sci U S A ; 118(3)2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33397805

RESUMEN

The CA (capsid) domain of immature HIV-1 Gag and the adjacent spacer peptide 1 (SP1) play a key role in viral assembly by forming a lattice of CA hexamers, which adapts to viral envelope curvature by incorporating small lattice defects and a large gap at the site of budding. This lattice is stabilized by intrahexameric and interhexameric CA-CA interactions, which are important in regulating viral assembly and maturation. We applied subtomogram averaging and classification to determine the oligomerization state of CA at lattice edges and found that CA forms partial hexamers. These structures reveal the network of interactions formed by CA-SP1 at the lattice edge. We also performed atomistic molecular dynamics simulations of CA-CA interactions stabilizing the immature lattice and partial CA-SP1 helical bundles. Free energy calculations reveal increased propensity for helix-to-coil transitions in partial hexamers compared to complete six-helix bundles. Taken together, these results suggest that the CA dimer is the basic unit of lattice assembly, partial hexamers exist at lattice edges, these are in a helix-coil dynamic equilibrium, and partial helical bundles are more likely to unfold, representing potential sites for HIV-1 maturation initiation.


Asunto(s)
Proteínas de la Cápside/ultraestructura , Infecciones por VIH/genética , VIH-1/genética , Factor de Transcripción Sp1/ultraestructura , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/ultraestructura , Cápside/química , Cápside/ultraestructura , Proteínas de la Cápside/genética , Cristalografía por Rayos X , Infecciones por VIH/virología , Seropositividad para VIH , VIH-1/patogenicidad , VIH-1/ultraestructura , Humanos , Simulación de Dinámica Molecular , Multimerización de Proteína/genética , Proteolisis , Factor de Transcripción Sp1/química , Factor de Transcripción Sp1/genética , Virión/genética , Virión/patogenicidad , Ensamble de Virus/genética , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/química , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética
7.
J Antimicrob Chemother ; 78(2): 373-379, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36480295

RESUMEN

BACKGROUND: Nitrofurantoin has been re-introduced as a first-choice antibiotic to treat uncomplicated acute urinary tract infections in England and Wales. Highly effective against common uropathogens such as Escherichia coli, its use is accompanied by a low incidence (<10%) of antimicrobial resistance. Resistance to nitrofurantoin is predominantly via the acquisition of loss-of-function, step-wise mutations in the nitroreductase genes nfsA and nfsB. OBJECTIVE: To explore the in situ evolution of NitR in E. coli isolates from 17 patients participating in AnTIC, a 12-month open label randomized controlled trial assessing the efficacy of antibiotic prophylaxis in reducing urinary tract infections (UTIs) incidence in clean intermittent self-catheterizing patients. METHODS: The investigation of NitR evolution in E. coli used general microbiology techniques and genetics to model known NitR mutations in NitSE. coli strains. RESULTS: Growth rate analysis identified a 2%-10% slower doubling time for nitrofurantoin resistant strains: NitS: 20.8 ±â€Š0.7 min compared to NitR: 23 ±â€Š0.8 min. Statistically, these data indicated no fitness advantage of evolved strains compared to the sensitive predecessor (P-value = 0.13). Genetic manipulation of E. coli to mimic NitR evolution, supported no fitness advantage (P-value = 0.22). In contrast, data argued that a first-step mutant gained a selective advantage, at sub-MIC (4-8 mg/L) nitrofurantoin concentrations. CONCLUSION: Correlation of these findings to nitrofurantoin pharmacokinetic data suggests that the low incidence of E. coli NitR, within the community, is driven by urine-based nitrofurantoin concentrations that selectively inhibit the growth of E. coli strains carrying the key first-step loss-of-function mutation.


Asunto(s)
Infecciones por Escherichia coli , Infecciones Urinarias , Escherichia coli Uropatógena , Humanos , Nitrofurantoína/farmacología , Nitrofurantoína/uso terapéutico , Escherichia coli Uropatógena/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones Urinarias/microbiología , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Pruebas de Sensibilidad Microbiana
8.
Int J Mol Sci ; 24(4)2023 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-36835536

RESUMEN

The advent of tyrosine kinase inhibitors (TKIs) for treating epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) has been a game changer in lung cancer therapy. However, patients often develop resistance to the drugs within a few years. Despite numerous studies that have explored resistance mechanisms, particularly in regards to collateral signal pathway activation, the underlying biology of resistance remains largely unknown. This review focuses on the resistance mechanisms of EGFR-mutated NSCLC from the standpoint of intratumoral heterogeneity, as the biological mechanisms behind resistance are diverse and largely unclear. There exist various subclonal tumor populations in an individual tumor. For lung cancer patients, drug-tolerant persister (DTP) cell populations may have a pivotal role in accelerating the evolution of tumor resistance to treatment through neutral selection. Cancer cells undergo various changes to adapt to the new tumor microenvironment caused by drug exposure. DTP cells may play a crucial role in this adaptation and may be fundamental in mechanisms of resistance. Intratumoral heterogeneity may also be precipitated by DNA gains and losses through chromosomal instability, and the role of extrachromosomal DNA (ecDNA) may play an important role. Significantly, ecDNA can increase oncogene copy number alterations and enhance intratumoral heterogeneity more effectively than chromosomal instability. Additionally, advances in comprehensive genomic profiling have given us insights into various mutations and concurrent genetic alterations other than EGFR mutations, inducing primary resistance in the context of tumor heterogeneity. Understanding the mechanisms of resistance is clinically crucial since these molecular interlayers in cancer-resistance mechanisms may help to devise novel and individualized anticancer therapeutic approaches.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Resistencia a Antineoplásicos/genética , Receptores ErbB/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Microambiente Tumoral , /farmacología
9.
Aust J Rural Health ; 31(5): 878-885, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37350539

RESUMEN

INTRODUCTION: Stroke in Regional Australia may have worse outcomes due to difficulties accessing optimal care. The South Australian Regional Telestroke service aimed to improve telestroke neurologist access, supported by improved ambulance triage. OBJECTIVE: To assess stroke care quality and patient mortality pre- and postimplementation of a vascular neurologist-led Telestroke service. DESIGN: Historically controlled mixed methods cohort study comparing key quality indicators and patient mortality (6 months pre- vs. 18 months postimplementation date [4 June 2018]) at the three major South Australian regional stroke centres. The primary outcome was 13 care quality indicators as a combined composite risk-adjusted score, and the secondary outcome was risk-adjusted mortality at 12-month postadmission. FINDINGS: On an annualised basis, of 189 patients with stroke, more were admitted postintervention to the regional stroke centres than in the control period (158 [annualised rate 105.3, 95% CI 86.2-127.4] vs. 31 [annualised rate 62.0, 95% CI 47.5-79.5]) Baseline patient characteristics were similar in both periods. Post-implementation, median last-known-well time to presentation (3.5 h [IQR 1.6-17] vs. 2.0 [IQR 1-14]; p = 0.46) and door to needle times (121 min [IQR 97-144] vs. 90 [IQR 75-138]; p = 0.65) were not significantly lower but an improvement in the combined composite quality score was observed (0.069 [95% CI 0.004-0.134; p = 0.04]), reflecting individual improvements in some quality indicators. Mortality at 12-month postimplementation was substantially lower postimplementation (prechange 23% vs. postchange 13% [hazard ratio 0.58 (95% CI 0.44-0.76; p < 0.001)]). CONCLUSION: Implementation of a South Australian Regional Telestroke service was associated with improved care metrics and lower mortality.


Asunto(s)
Accidente Cerebrovascular , Telemedicina , Humanos , Fibrinolíticos/uso terapéutico , Terapia Trombolítica , Australia del Sur , Estudios Retrospectivos , Estudios de Cohortes , Telemedicina/métodos , Resultado del Tratamiento , Australia , Accidente Cerebrovascular/terapia , Activador de Tejido Plasminógeno/uso terapéutico
10.
Oncologist ; 27(1): 22-29, 2022 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-34523767

RESUMEN

BACKGROUND: LIBRETTO-001 is an ongoing, global, open-label, phase I/II study of selpercatinib in patients with advanced or metastatic solid tumors. We report interim patient-reported outcomes in patients with RET fusion-positive non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients completed the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (QLQ-C30) version 3.0 at baseline (cycle 1, day 1), approximately every other 28-day cycle until cycle 13, and every 12 weeks thereafter. Data were evaluated through cycle 13 as few patients had reached later time points. A change of ≥10 points from baseline in domain scores was considered clinically meaningful. RESULTS: Among 253 selpercatinib-treated patients, 239 were categorized into subgroups by prior therapy: treatment-naïve (n = 39), one prior line of therapy (n = 64), or two or more prior lines of therapy (n = 136). The QLQ-C30 was completed by >85% of patients at each time point. Most patients overall and in each subgroup maintained or improved in all health-related quality of life (HRQoL) domains during treatment. The percentage of patients who experienced clinically meaningful improvements ranged from 61.1% to 66.7% for global health status, 33.3% to 61.1% for dyspnea, and 46.2% to 63.0% for pain. The 61.1% of patients with improved dyspnea had two or more prior lines of therapy; median time to first improvement was 3.4 months. At the first postbaseline evaluation (cycle 3), 45.9% of all patients reported a ≥10-point reduction in pain. CONCLUSION: In this interim analysis, the majority of patients with RET fusion-positive NSCLC remained stable or improved on all QLQ-C30 subscales at each study visit, demonstrating favorable HRQoL as measured by the QLQ-C30 during treatment with selpercatinib.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Disnea , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Dolor , Medición de Resultados Informados por el Paciente , Proteínas Proto-Oncogénicas c-ret/análisis , Pirazoles , Piridinas , Calidad de Vida
11.
Int J Mol Sci ; 23(16)2022 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-36012123

RESUMEN

The management of advanced lung cancer has been transformed with the identification of targetable oncogenic driver alterations. This includes anaplastic lymphoma kinase (ALK) gene rearrangements. ALK tyrosine kinase inhibitors (TKI) are established first-line treatment options in advanced ALK rearranged non-small cell lung cancer (NSCLC), with several next-generation ALK TKIs (alectinib, brigatinib, ensartinib and lorlatinib) demonstrating survival benefit compared with the first-generation ALK TKI crizotinib. Still, despite high objective response rates and durable progression-free survival, drug resistance inevitably ensues, and treatment options beyond ALK TKI are predominantly limited to cytotoxic chemotherapy. Anti-angiogenic therapy targeting the vascular endothelial growth factor (VEGF) signaling pathway has shown efficacy in combination with platinum-doublet chemotherapy in advanced NSCLC without a driver alteration, and with EGFR TKI in advanced EGFR mutated NSCLC. The role for anti-angiogenic therapy in ALK rearranged NSCLC, however, remains to be elucidated. This review will discuss the pre-clinical rationale, clinical trial evidence to date, and future directions to evaluate anti-angiogenic therapy in ALK rearranged NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Quinasa de Linfoma Anaplásico/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Receptores ErbB/genética , Reordenamiento Génico , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas/genética , Factor A de Crecimiento Endotelial Vascular/genética
12.
Mol Psychiatry ; 25(6): 1323-1333, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-30385872

RESUMEN

Major depressive disorder (MDD) is a leading cause of disability worldwide, yet current treatment strategies remain limited in their mechanistic diversity. Recent evidence has highlighted a promising novel pharmaceutical target-the KCNQ-type potassium channel-for the treatment of depressive disorders, which may exert a therapeutic effect via functional changes within the brain reward system, including the ventral striatum. The current study assessed the effects of the KCNQ channel opener ezogabine (also known as retigabine) on reward circuitry and clinical symptoms in patients with MDD. Eighteen medication-free individuals with MDD currently in a major depressive episode were enrolled in an open-label study and received ezogabine up to 900 mg/day orally over the course of 10 weeks. Resting-state functional magnetic resonance imaging data were collected at baseline and posttreatment to examine brain reward circuitry. Reward learning was measured using a computerized probabilistic reward task. After treatment with ezogabine, subjects exhibited a significant reduction of depressive symptoms (Montgomery-Asberg Depression Rating Scale score change: -13.7 ± 9.7, p < 0.001, d = 2.08) and anhedonic symptoms (Snaith-Hamilton Pleasure Scale score change: -6.1 ± 5.3, p < 0.001, d = 1.00), which remained significant even after controlling for overall depression severity. Improvement in depression was associated with decreased functional connectivity between the ventral caudate and clusters within the mid-cingulate cortex and posterior cingulate cortex (n = 14, voxel-wise p < 0.005). In addition, a subgroup of patients tested with a probabilistic reward task (n = 9) showed increased reward learning following treatment. These findings highlight the KCNQ-type potassium channel as a promising target for future drug discovery efforts in mood disorders.


Asunto(s)
Carbamatos/farmacología , Carbamatos/uso terapéutico , Trastorno Depresivo Mayor/tratamiento farmacológico , Activación del Canal Iónico/efectos de los fármacos , Fenilendiaminas/farmacología , Fenilendiaminas/uso terapéutico , Estriado Ventral/efectos de los fármacos , Trastorno Depresivo Mayor/metabolismo , Femenino , Humanos , Canales de Potasio KCNQ/agonistas , Canales de Potasio KCNQ/metabolismo , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recompensa , Estriado Ventral/metabolismo
13.
Proc Natl Acad Sci U S A ; 115(40): E9401-E9410, 2018 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-30217893

RESUMEN

HIV-1 maturation occurs via multiple proteolytic cleavages of the Gag polyprotein, causing rearrangement of the virus particle required for infectivity. Cleavage results in beta-hairpin formation at the N terminus of the CA (capsid) protein and loss of a six-helix bundle formed by the C terminus of CA and the neighboring SP1 peptide. How individual cleavages contribute to changes in protein structure and interactions, and how the mature, conical capsid forms, are poorly understood. Here, we employed cryoelectron tomography to determine morphology and high-resolution CA lattice structures for HIV-1 derivatives in which Gag cleavage sites are mutated. These analyses prompt us to revise current models for the crucial maturation switch. Unlike previously proposed, cleavage on either terminus of CA was sufficient, in principle, for lattice maturation, while complete processing was needed for conical capsid formation. We conclude that destabilization of the six-helix bundle, rather than beta-hairpin formation, represents the main determinant of structural maturation.


Asunto(s)
VIH-1 , Productos del Gen gag del Virus de la Inmunodeficiencia Humana , Microscopía por Crioelectrón , Células HEK293 , VIH-1/genética , VIH-1/metabolismo , VIH-1/ultraestructura , Humanos , Mutación , Dominios Proteicos , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/metabolismo
14.
Mov Disord ; 35(12): 2250-2260, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32894625

RESUMEN

BACKGROUND: Helicobacter pylori (HP) infection has been associated with worse motor function in Parkinson's disease (PD). OBJECTIVE: We aimed to evaluate the effects of HP eradication on PD symptoms. METHODS: In this parallel-group, double-blind, randomized placebo-controlled, single-center trial, patients with PD with positive HP urea breath test and serology were block randomized (1:1) to receive standard eradication triple therapy or identically appearing placebo capsules for 1 week. Prespecified motor (International Parkinson and Movement Disorder Society Unified PD Rating Scale [MDS-UPDRS], timed tests, and home-based wearable sensor measurements), nonmotor (Leeds Dyspepsia Questionnaire and Montreal Cognitive Assessment), and quality-of-life (Parkinson's Disease Questionnaire-39) outcome measures were assessed at weeks 6, 12, 24, and 52. The primary outcome was the baseline-to-week 12 change in ON medication MDS-UPDRS motor scores. Lactulose-hydrogen breath testing for concomitant small intestinal bacterial overgrowth was performed at baseline and repeated at week 24, together with the urea breath test. RESULTS: A total of 310 patients were screened for eligibility and 80 were randomly assigned, of whom 67 were included in the full-analysis set (32 treatment group patients, 35 placebo patients). HP eradication did not improve MDS-UPDRS motor scores at week 12 (mean difference 2.6 points in favor of placebo, 95% confidence interval: -0.4 to 5.6, P = 0.089). There was no significant improvement in any motor, nonmotor, or quality-of-life outcome at weeks 12 and 52. Both the full-analysis and per-protocol analyses (based on eradication status) supported these conclusions. Small intestinal bacterial overgrowth status did not influence treatment results. CONCLUSIONS: HP eradication does not improve clinical outcomes in PD, suggesting that there is no justification for routine HP screening or eradication with the goal of improving PD symptoms. © 2020 International Parkinson and Movement Disorder Society.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Enfermedad de Parkinson , Método Doble Ciego , Infecciones por Helicobacter/tratamiento farmacológico , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/tratamiento farmacológico , Calidad de Vida , Encuestas y Cuestionarios
15.
Chem Rev ; 118(14): 6766-6843, 2018 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-29969244

RESUMEN

Research pertaining to conductive polymers has gained significant traction in recent years, and their applications range from optoelectronics to material science. For all intents and purposes, conductive polymers can be described as Nobel Prize-winning materials, given that their discoverers were awarded the Nobel Prize in Chemistry in 2000. In this review, we seek to describe the chemical forms and functionalities of the main types of conductive polymers, as well as their synthesis methods. We also present an in-depth analysis of composite conductive polymers that contain various nanomaterials such as graphene, fullerene, carbon nanotubes, and paramagnetic metal ions. Natural polymers such as collagen, chitosan, fibroin, and hydrogel that are structurally modified for them to be conductive are also briefly touched upon. Finally, we expound on the plethora of biomedical applications that harbor the potential to be revolutionized by conductive polymers, with a particular focus on tissue engineering, regenerative medicine, and biosensors.


Asunto(s)
Polímeros/química , Técnicas Biosensibles , Quitosano/química , Grafito/química , Hidrogeles/química , Nanoestructuras/química , Nanotubos de Carbono/química , Corona de Proteínas , Medicina Regenerativa , Ingeniería de Tejidos
16.
Dermatol Surg ; 46(11): e82-e87, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32068548

RESUMEN

BACKGROUND: Picosecond lasers have become very popular in the treatment of hyperpigmentation. OBJECTIVE: Evaluating the efficacy and safety of picosecond 755-nm laser in treatment of nevi of Ota (NO) and Hori's nevi (HN) in Asians with Fitzpatrick skin Types III/IV. METHODS: A retrospective review of patient records at the National Skin Center, Singapore, from 2015 to 2017. Three independent blinded dermatologists assessed pre-and-post treatment photographs using the physician's global assessment (PGA) score (0-clear, 1-almost clear, 2-mild, 3-moderate, and 4-severe). RESULTS: There were 18 cases of NO and 11 cases of HN. Mean treatment sessions were 2.22 (NO; range 1-6) and 3.82 (HN; range 1-6). In the NO group, mean pre-and-post treatment PGA scores were 3.1 and 1.3, respectively (1.8 point change, p-value 0.0002), and average fluence used was 2.02 J/cm (range: 1.02-2.38). In the HN group, mean pre-and-post treatment PGA scores were 2.6 and 1.1, respectively (1.5 point change, p-value 0.004), and average fluence was 2.08 J/cm (range: 1.98-3.40). Eleven patients (37.9%) experienced postlaser erythema, and 1 (3.4%) patient developed transient postlaser hypopigmentation. No permanent hyper/hypopigmentation was seen. CONCLUSION: The picosecond 755-nm laser is effective in the treatment of dermal pigmentary conditions in Asians with Fitzpatrick skin Types III/IV, with minimal risk of postlaser complications, and compared with the center's past experience with the Q-switched nanosecond 1064-nm laser, results in faster and more effective pigment clearance.


Asunto(s)
Hiperpigmentación/radioterapia , Láseres de Estado Sólido/efectos adversos , Terapia por Luz de Baja Intensidad/métodos , Nevo de Ota/radioterapia , Neoplasias Cutáneas/radioterapia , Adulto , Pueblo Asiatico , Eritema/epidemiología , Eritema/etiología , Femenino , Humanos , Hiperpigmentación/diagnóstico , Hipopigmentación/epidemiología , Hipopigmentación/etiología , Terapia por Luz de Baja Intensidad/efectos adversos , Terapia por Luz de Baja Intensidad/instrumentación , Masculino , Persona de Mediana Edad , Nevo de Ota/diagnóstico , Estudios Retrospectivos , Singapur , Piel/efectos de la radiación , Neoplasias Cutáneas/diagnóstico , Resultado del Tratamiento , Adulto Joven
17.
Int J Mol Sci ; 21(4)2020 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-32093103

RESUMEN

The management of non-small cell lung cancer (NSCLC) has transformed with the discovery of therapeutically tractable oncogenic drivers. In addition to activating driver mutations, gene fusions or rearrangements form a unique sub-class, with anaplastic lymphoma kinase (ALK) and c-ros oncogene 1 (ROS1) targeted agents approved as the standard of care in the first-line setting for advanced disease. There are a number of emerging fusion drivers, however, including neurotrophin kinase (NTRK), rearrangement during transfection (RET), and neuregulin 1 (NRG1) for which there are evolving high-impact systemic treatment options. Brain metastases are highly prevalent in NSCLC patients, with molecularly selected populations such as epidermal growth factor receptor (EGFR) mutant and ALK-rearranged tumors particularly brain tropic. Accordingly, there exists a substantial body of research pertaining to the understanding of brain metastases in such populations. Little is known, however, on the molecular mechanisms of brain metastases in those with other targetable fusion drivers in NSCLC. This review encompasses key areas including the biological underpinnings of brain metastases in fusion-driven lung cancers, the intracranial efficacy of novel systemic therapies, and future directions required to optimize the control and prevention of brain metastases.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/secundario , Neoplasias Pulmonares/genética , Proteínas de Fusión Oncogénica/genética , Quinasa de Linfoma Anaplásico/genética , Quinasa de Linfoma Anaplásico/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica , Barrera Hematoencefálica/efectos de los fármacos , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/terapia , Carcinoma de Pulmón de Células no Pequeñas/terapia , Receptores ErbB/genética , Receptores ErbB/metabolismo , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/terapia , Terapia Molecular Dirigida , Metástasis de la Neoplasia/genética , Neurregulina-1/genética , Neurregulina-1/metabolismo , Proteínas de Fusión Oncogénica/metabolismo , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-ret/genética , Proteínas Proto-Oncogénicas c-ret/metabolismo , Receptor trkA/genética , Receptor trkA/metabolismo
18.
Carbon N Y ; 50(4): 1625-1634, 2019 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-31105316

RESUMEN

Carbon nanotubes (CNTs) have emerged as promising drug delivery systems particularly for cancer therapy, due to their abilities to overcome some of the challenges faced by cancer treatment, namely non-specificity, poor permeability into tumour tissues, and poor stability of anticancer drugs. Encapsulation of anticancer agents inside CNTs provides protection from external deactivating agents. However, the open ends of the CNTs leave the encapsulated drugs exposed to the environment and eventually their uncontrolled release before reaching the desired target. In this study, we report the successful encapsulation of cisplatin, a FDA-approved chemotherapeutic drug, into multi-walled carbon nanotubes and the capping at the ends with functionalised gold nanoparticles to achieve a "carbon nanotube bottle" structure. In this proof-of-concept study, these caps did not prevent the encapsulation of drug in the inner space of CNTs; on the contrary, we achieved higher drug loading inside the nanotubes in comparison with data reported in literature. In addition, we demonstrated that encapsulated cisplatin could be delivered in living cells under physiological conditions to exert its pharmacological action.

19.
Support Care Cancer ; 27(12): 4771-4777, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30972648

RESUMEN

BACKGROUND: Patient-reported outcomes (PRO) are becoming increasingly recognised as essential to comprehensively collect chemotherapy-induced peripheral neuropathy (CIPN) symptom information. MATERIALS AND METHODS: This study aimed to evaluate the utility and feasibility of CIPN PRO assessment tools in a real-world clinical setting through investigation of the correlation of PRO with NCI-CTCAE assessments particularly in relation to cumulative dose of chemotherapy. Patients receiving oxaliplatin or paclitaxel chemotherapy in Sydney, Australia, completed a questionnaire containing standardised CIPN PRO assessments (EORTC CIPN-20, PRO-CTCAE) via tablet device. PRO assessment scores were correlated with NCI-CTCAE grade determined by nursing assessment and analysed with respect to cumulative dose of chemotherapy. RESULTS: There were 87 patients who completed a total of 145 questionnaires, 68 in patients receiving oxaliplatin and 77 in patients receiving paclitaxel. CIPN PRO scores were associated with NCI-CTCAE grade, for EORTC CIPN-20 (r2 = 0.19, p < 0.01) and PRO-CTCAE (r2 = 0.41, p < 0.01), although individual patient correlation was poor. PRO assessments, however, identified higher grade symptoms, in particular symptoms causing functional impairment, at lower doses of cumulative chemotherapy compared to NCI-CTCAE. CONCLUSION: This study demonstrated that CIPN PRO may provide complementary information to nursing assessed NCI-CTCAE grade, particularly in earlier stages of chemotherapy and can be considered an important component in the comprehensive assessment of neuropathy.


Asunto(s)
Síndromes de Neurotoxicidad/etiología , Oxaliplatino/efectos adversos , Paclitaxel/efectos adversos , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Australia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Síndromes de Neurotoxicidad/diagnóstico , Oxaliplatino/uso terapéutico , Paclitaxel/uso terapéutico , Medición de Resultados Informados por el Paciente , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Encuestas y Cuestionarios
20.
Intern Med J ; 49(6): 734-739, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30411448

RESUMEN

BACKGROUND: Patients with advanced malignancies have historically been considered poor candidates for admission to the intensive care unit (ICU); however, prognosis is continually improving, and requirements for ICU access are increasing. AIM: To understand the characteristics and outcomes of oncology unit patients admitted to an Australian ICU and identify potential prognostic factors. METHODS: A single-centre, retrospective, cohort study conducted at a tertiary public hospital with a quaternary ICU in Sydney, Australia. All patients admitted under the medical oncology team requiring ICU admission between June 2014 and June 2016 were evaluated. Clinical outcomes were determined including mortality, ICU requirements (ventilation, dialysis, vasopressors, infection) and prognostic scores (Acute Physiologic and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) score). RESULTS: There were 96 patients with mean age 61 years, 58% were male and 76% had metastatic disease. Most were receiving palliative treatment (89%), with recent chemotherapy (43%), immunotherapy (10%) and other therapies (5%). Of the 10 patients with recent immunotherapy, three (all with melanoma) required ICU admission due to immunotoxicity; 13% were admitted due to an oncological emergency. Mean APACHE II score was 17 (standard deviation (SD) 5.33), mean SOFA score was 3.99 (SD 2.70), ICU mortality was 5% and hospital mortality was 22%. Using multivariate logistic regression analysis, cancer stage, infection during ICU admission, intracranial mass effect on ICU admission and SOFA score were associated with 30-day mortality. CONCLUSION: Our patient population had good short-term survival outcomes despite most receiving palliative treatment. Cancer patients can achieve positive outcomes after ICU admission, and appropriate selection of patients is crucial.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Neoplasias/mortalidad , Neoplasias/terapia , APACHE , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Australia/epidemiología , Femenino , Mortalidad Hospitalaria , Hospitales Públicos , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Puntuaciones en la Disfunción de Órganos , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Centros de Atención Terciaria , Adulto Joven
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