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1.
Phys Rev Lett ; 132(5): 056101, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38364152

RESUMO

The slow transition from an out-of-equilibrium glass towards a supercooled liquid is a complex relaxation phenomenon. In this Letter, we study the correlation between mechanical relaxation and equilibration kinetics in a Pd_{20}Pt_{20}Cu_{20}Ni_{20}P_{20} high-entropy metallic glass. The evolution of stress relaxation with aging time was obtained with an unprecedented detail, allowing us to pinpoint new interesting features. The long structural relaxation towards equilibrium contains a wide distribution of activation energies, instead of being just associated to the ß relaxation as commonly accepted. The stress relaxation time can be correlated with the equilibration rate and we observe a decrease of microstructural heterogeneity which contrasts with an increase of dynamic heterogeneity. These results significantly enhance our insight of the interplay between relaxation dynamics and thermodynamics in metallic glasses.

2.
J Neurooncol ; 168(2): 299-306, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38630385

RESUMO

PURPOSE: The impact of age on optimal management of glioblastoma remains unclear. A recent combined analysis of two randomised trials, GEINO14-01 and EX-TEM, found no benefit from extending post-radiation temozolomide in newly diagnosed glioblastoma. Here, we explore the impact of age. METHODS: Relevant intergroup statistics were used to identify differences in tumour, treatment and outcome characteristics based on age with elderly patients (EP) defined as age 65 years and over. Survival was estimated using the Kaplan Meier method. RESULTS: Of the combined 205 patients, 57 (28%) were EP. Of these, 95% were ECOG 0-1 and 65% underwent macroscopic resection compared with 97% and 61% of younger patients (YP) respectively. There were numerically less MGMT-methylated (56% vs. 63%, p = 0.4) and IDH-mutated (4% vs. 13%, p = 0.1) tumours in EP vs. YP. Following surgery, EP were more likely to receive short course chemoradiation (17.5% vs. 6%, p = 0.017). At recurrence, EP tended to receive or best supportive care (28.3% vs. 15.4%, p = 0.09) or non-surgical options (96.2% vs. 84.6%, p = 0.06), but were less likely to receive bevacizumab (23.1% vs. 49.5%, p < 0.01). Median PFS was similar at 9.3months in EP and 8.5months in YP, with similar median OS at 20months. CONCLUSION: In this trial population of predominantly fit EP, survival was similar to YP despite a proportion receiving less aggressive therapy at diagnosis and recurrence. Advancing age does not appear to be an adverse prognostic factor for glioblastoma when patients are fit for treatment, and a less aggressive approach in selected patients may not compromise outcomes.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/terapia , Glioblastoma/mortalidade , Idoso , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Temozolomida/uso terapêutico , Adulto , Antineoplásicos Alquilantes/uso terapêutico , Fatores Etários , Terapia Combinada , Resultado do Tratamento , Gerenciamento Clínico
3.
J Neurooncol ; 166(3): 407-415, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38153582

RESUMO

PURPOSE: The optimal duration of post-radiation temozolomide in newly diagnosed glioblastoma remains unclear, with no published phase III randomised trials. Standard-of-care stipulates 6 months. However, in routine care, it is often extended to 12 months, despite lacking robust supporting data. METHODS: GEINO14-01 (Spain) and EX-TEM (Australia) studies enrolled glioblastoma patients without progression at the end of 6 months post-radiation temozolomide. Participants were randomised 1:1 to six additional months of temozolomide or observation. Primary endpoint was 6-month progression free survival from date of randomisation (6mPFS). Secondary endpoints included overall survival (OS) and toxicity. 204 patients were required to detect an improvement in 6mPFS from 50 to 60% (80% power). Neither study recruited sufficient patients. We performed a combined analysis of individual patient data. RESULTS: 205 patients were recruited: 159 in GEINO14-01 (2014-2018) and 46 in EX-TEM (2019-2022). Median follow-up was 20.0 and 14.5 months. Baseline characteristics were balanced. There was no significant improvement in 6mPFS (57.2% vs 64.0%, OR0.75, p = 0.4), nor across any subgroups, including MGMT methylated; PFS (HR0.92, p = 0.59, median 7.8 vs 9.7 months); or OS (HR1.03, p = 0.87, median 20.1 vs 19.4 months). During treatment extension, 64% experienced any grade adverse event, mainly fatigue and gastrointestinal (both 54%). Only a minority required treatment changes: 4.5% dose delay, 7.5% dose reduction, 1.5% temozolomide discontinuation. CONCLUSION: For glioblastoma patients, extending post-radiation temozolomide from 6 to 12 months is well tolerated but does not improve 6mPFS. We could not identify any subset that benefitted from extended treatment. Six months should remain standard-of-care.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Estudos Prospectivos , Dacarbazina/efeitos adversos , Intervalo Livre de Doença , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Antineoplásicos Alquilantes/efeitos adversos
4.
Phys Rev Lett ; 129(17): 175501, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36332263

RESUMO

Lacking the structural information of crystalline solids, the origin of the relaxation dynamics of metallic glasses is unclear. Here, we report the evolution of stress relaxation of high-entropy metallic glasses with distinct ß relaxation behavior. The fraction of liquidlike zones, determined at each temperature by the intensity of stress decay, is shown to be directly related to both the aging process and the spectrum of relaxation modes obtained by mechanical spectroscopy. The results shed light on the intrinsic correlation between the static and dynamic mechanical response in high-entropy and conventional metallic glasses, pointing toward a sluggish diffusion high-entropy effect in the liquid dynamics.

6.
Gynecol Oncol ; 161(2): 516-520, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33618842

RESUMO

OBJECTIVES: Genetic testing (GT) companies have developed patient education videos to supplement or replace pre-test genetic counseling (GC) by certified genetic counselors (CGC). The aim of this study was to assess the quality of these videos compared to the standard of care (SOC). METHODS: Videos from four major GT companies were selected from an internet search identifying pre-test patient education videos. A scoring rubric with 22 questions and 36 total points was devised to assess quality metrics, as described by the National Cancer Institute and National Society of Genetic Counselors. Twenty-two individuals with varying genetics expertise (3 gynecologic oncologists, 3 academic generalists, 4 CGC, a genetics community health worker, 3 cancer care navigators, and 8 medical students) scored each video. Scorers were blinded to others' assessments. RESULTS: Invitae had the highest median score (26/36), followed by Myriad (22/36), Ambry (17.5/36), and Color (15/36). All videos scored highly in explaining DNA basics, cancer development, and hereditary cancer predisposition. All addressed benefits of GT but failed to address potential disadvantages. All scored poorly in explaining medical terms and different GT options. There was variability in addressing patient concerns including cost, privacy, and procedure. CONCLUSIONS: There is significant variation in the content of pre-test patient education videos between GT companies. None of the videos met the SOC for pre-test GC, and none addressed disadvantages of GT, possibly due to a conflict of interest. With improvement in content, accessibility, and use of interactive platforms, these videos may serve as an adjunct to in-person pre-test GC.


Assuntos
Aconselhamento Genético/métodos , Testes Genéticos/métodos , Neoplasias/genética , Educação de Pacientes como Assunto/métodos , Aconselhamento Genético/ética , Aconselhamento Genético/normas , Testes Genéticos/ética , Testes Genéticos/normas , Humanos , Educação de Pacientes como Assunto/normas , Gravação de Videoteipe/ética , Gravação de Videoteipe/normas
8.
Ann Oncol ; 29(10): 2121-2128, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30165419

RESUMO

Background: We hypothesized that the abundance of PD1 mRNA in tumor samples might explain the differences in overall response rates (ORR) observed following anti-PD1 monotherapy across cancer types. Patients and methods: RNASeqv2 data from 10 078 tumor samples representing 34 different cancer types was analyzed from TCGA. Eighteen immune-related gene signatures and 547 immune-related genes, including PD1, were explored. Correlations between each gene/signature and ORRs reported in the literature following anti-PD1 monotherapy were calculated. To translate the in silico findings to the clinical setting, we analyzed the expression of PD1 mRNA using the nCounter platform in 773 formalin-fixed paraffin embedded (FFPE) tumor samples across 17 cancer types. To test the direct relationship between PD1 mRNA, PDL1 immunohistochemistry (IHC), stromal tumor-infiltrating lymphocytes (sTILs) and ORR, we evaluated an independent FFPE-based dataset of 117 patients with advanced disease treated with anti-PD1 monotherapy. Results: In pan-cancer TCGA, PD1 mRNA expression was found strongly correlated (r > 0.80) with CD8 T-cell genes and signatures and the proportion of PD1 mRNA-high tumors (80th percentile) within a given cancer type was variable (0%-84%). Strikingly, the PD1-high proportions across cancer types were found strongly correlated (r = 0.91) with the ORR following anti-PD1 monotherapy reported in the literature. Lower correlations were found with other immune-related genes/signatures, including PDL1. Using the same population-based cutoff (80th percentile), similar proportions of PD1-high disease in a given cancer type were identified in our in-house 773 tumor dataset as compared with TCGA. Finally, the pre-established PD1 mRNA FFPE-based cutoff was found significantly associated with anti-PD1 response in 117 patients with advanced disease (PD1-high 51.5%, PD1-intermediate 26.6% and PD1-low 15.0%; odds ratio between PD1-high and PD1-intermediate/low = 8.31; P < 0.001). In this same dataset, PDL1 tumor expression by IHC or percentage of sTILs was not found associated with response. Conclusions: Our study provides a clinically applicable assay that links PD1 mRNA abundance, activated CD8 T-cells and anti-PD1 efficacy.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Linfócitos T CD8-Positivos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Neoplasias/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , RNA Mensageiro/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linfócitos T CD8-Positivos/imunologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Linfócitos do Interstício Tumoral/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Neoplasias/imunologia , Neoplasias/patologia , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/genética , RNA Mensageiro/genética , Taxa de Sobrevida
9.
Andrologia ; 49(9)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28543267

RESUMO

One of the cryopreservation methods that best preserves sperm function is vitrification. However, comparative studies have not been performed to evaluate the effect of nonpermeable cryoprotectors on sperm function for prolonged periods of time post-devitrification. These times are necessary, especially in in vitro fertilisation and intrauterine insemination, for gamete interaction and then fertilisation to occur, while maintaining motility to arrive at the fertilisation site. In this study, sucrose (.25 m) and trehalose (.1 and .05 m) were compared in essential parameters like motility and plasma membrane integrity for 12 hr. Post-devitrification sperm motility using .1 m trehalose was 68.9%, higher than that obtained with .05 m trehalose (59.9%, p < .0081) and .25 m sucrose (57.9%, p < .0002). Similar results were obtained at 6 and 12 hr with .1 m trehalose (58.0% and 42.3% respectively) compared to .05 m trehalose (p < .0184 and p < .033) and .25 m sucrose (p < .0001 and p < .0012).There was no difference between .25 m sucrose and .05 m trehalose. Membrane integrity was best preserved at time 0 by .1 m trehalose (p < .05), but there was no significance at 6 and 12 hr compared to sucrose. Our results suggest that for assisted reproduction techniques that require motile spermatozoa for a longer period of time, use of .1 m trehalose is recommended in the sperm vitrification technique.


Assuntos
Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides , Sacarose/farmacologia , Trealose/farmacologia , Vitrificação , Humanos , Masculino
10.
Support Care Cancer ; 24(5): 2129-2137, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26556209

RESUMO

BACKGROUND: The development of reliable alternatives to conventional hospitalization in patients with cancer would have great clinical and economical value. The aim of the present study was to assess the feasibility of a home-based nursing intervention model as a safe alternative for the management of acute medical complications in cancer patients who would otherwise require conventional hospitalization. PATIENTS AND METHODS: From October 2013 to October 2014, we prospectively evaluated the outcomes of consecutive acute medical episodes treated at home under the home-based intervention program named the Bridge Project (BP). Episodes were classified as "avoided hospitalization in outpatients" (AHO) vs. "reduced hospitalization in inpatients" (RHI). The primary end-point was to assess the rate and causes of BP intervention failure (unplanned hospital readmission or death). RESULTS: Two hundred and forty-six consecutive episodes (52 % AHO and 48 % RHI) involving 203 patients (55 % male; mean age 63 years) were enrolled. The main conditions managed at home were non-neutropenic infections (40 %), febrile neutropenia (20 %), and cancer-related complications (28 %). The median duration of the BP intervention was 5 days (range 1-16 days). No deaths were reported at home. Unplanned hospital readmissions occurred in 9 % of episodes (14 % in AHO vs. 4 % in RHI; p = 0.001). Five of the 22 readmitted patients (22.7 % of the BP failures; 2.5 % of the whole series) died during hospitalization. The BP intervention burden was 1353 days, representing a potential saving of 14 % of days of hospitalization during the study period. CONCLUSIONS: The BP is a safe intervention which can potentially avoid or reduce the length of hospitalization in selected cancer patients with acute medical complications. Our findings support further development of innovative home-based clinical approaches to promote potentially avoidable hospitalization in this setting.


Assuntos
Serviços de Assistência Domiciliar , Neoplasias/complicações , Neoplasias/terapia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/enfermagem , Readmissão do Paciente , Assistência Centrada no Paciente , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento
11.
Phys Rev Lett ; 109(16): 165701, 2012 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-23215091

RESUMO

We use x-ray photon correlation spectroscopy to investigate the structural relaxation process in a metallic glass on the atomic length scale. We report evidence for a dynamical crossover between the supercooled liquid phase and the metastable glassy state, suggesting different origins of the relaxation process across the transition. Furthermore, using different cooling rates, we observe a complex hierarchy of dynamic processes characterized by distinct aging regimes. Strong analogies with the aging dynamics of soft glassy materials, such as gels and concentrated colloidal suspensions, point at stress relaxation as a universal mechanism driving the relaxation dynamics of out-of-equilibrium systems.

12.
J Chem Phys ; 135(10): 101101, 2011 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-21932867

RESUMO

Using high resolution inelastic x-ray scattering we studied the collective dynamics of the Pd(77)Si(16.5)Cu(6.5) metallic glass, focusing on the energy-momentum region where the boson peak appears. The dispersion relation and the width of the acoustic excitations are determined showing how the longitudinal acoustic modes maintain their dispersive character for frequencies well above the boson peak frequencies. Moreover, we prove that close to these frequencies there is a softening of the apparent sound speed indicating a failure of the Debye continuum approximation at the boson peak frequencies and challenging previous results on other metallic glasses.

13.
Clin Transl Oncol ; 23(5): 940-947, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33792841

RESUMO

Recent advances in molecular profiling, have reclassified medulloblastoma, an undifferentiated tumor of the posterior fossa, in at least four diseases, each one with differences in prognosis, epidemiology and sensibility to different treatments. The recommended management of a lesion with radiological characteristics suggestive of MB includes maximum safe resection followed by a post-surgical MR < 48 h, LCR cytology and MR of the neuroaxis. Prognostic factors, such as presence of a residual tumor volume > 1.5 cm2, presence of micro- or macroscopic dissemination, and age > 3 years as well as pathological (presence of anaplastic or large cell features) and molecular findings (group, 4, 3 or p53 SHH mutated subgroup) determine the risk of relapse and should guide adjuvant management. Although there is evidence that both high-risk patients and to a lesser degree, standard-risk patients benefit from adjuvant craneoespinal radiation followed by consolidation chemotherapy, tolerability is a concern in adult patients, leading invariably to dose reductions. Treatment after relapse is to be considered palliative and inclusion on clinical trials, focusing on the molecular alterations that define each subgroup, should be encouraged. Selected patients can benefit from surgical rescue or targeted radiation or high-dose chemotherapy followed by autologous self-transplant. Even in patients that are cured by chemorradiation presence of significant sequelae is common and patients must undergo lifelong follow-up.


Assuntos
Neoplasias Cerebelares/diagnóstico , Neoplasias Cerebelares/terapia , Meduloblastoma/diagnóstico , Meduloblastoma/terapia , Adulto , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Cisplatino/efeitos adversos , Terapia Combinada/métodos , Medicina Baseada em Evidências , Humanos , Oncologia , Meduloblastoma/genética , Meduloblastoma/patologia , Terapia de Alvo Molecular/métodos , Recidiva Local de Neoplasia/terapia , Cuidados Paliativos , Complicações Pós-Operatórias/etiologia , Prognóstico , Radioterapia/efeitos adversos , Retratamento/métodos , Sociedades Médicas , Espanha , Vincristina/efeitos adversos
14.
Rev Neurol ; 73(11): 390-393, 2021 12 01.
Artigo em Espanhol | MEDLINE | ID: mdl-34826332

RESUMO

INTRODUCTION: Countries worldwide are having to cope with the COVID-19 pandemic caused by SARS-CoV-2. The burden on their national health systems is currently at unprecedented levels. Telemedicine care was initiated at an early stage in our centre. PATIENTS AND METHODS: We conducted a descriptive and retrospective study to evaluate the usefulness of telemedicine during lockdown in our centre. Patients included in the study had a clinical diagnosis of epilepsy, with two visits via telemedicine, who had been followed up for at least six months during the normal situation prior to the COVID-19 pandemic and two face-to-face consultations during the same period. RESULTS: A total of 115 patients were included. The average age was 29 years, 53% were males, 52.2% had focal epilepsy, 58.3% with a structural causation and 57.4% had difficult-to-treat epilepsy. The mean number of seizures prior to lockdown was 9.73/month and 6.54/month during lockdown. The number of patients who were seizure-free when lockdown ended was higher than that observed in the phase before it began: 54 versus 45 out of 115. CONCLUSIONS: Telemedicine is a very useful strategy for monitoring the course, progress and therapeutic changes in epileptic patients in the short and medium term. The reduction in the seizure frequency can be sustained in the medium term, not only in the short term as corroborated in previous studies. Telemedicine allows access to virtually all patients and closer monitoring.


TITLE: Telemedicina y epilepsia: experiencia asistencial de un centro de referencia nacional durante la pandemia de COVID-19.Introducción. El mundo entero está afrontando la pandemia por COVID-19 causada por el SARS-CoV-2. Los sistemas de salud nacionales están sometidos a niveles de sobrecarga sin precedentes. En nuestro centro se inició de forma temprana la asistencia a través de telemedicina. Pacientes y métodos. Es un estudio descriptivo y retrospectivo para evaluar la utilidad de la telemedicina durante el confinamiento en nuestro centro. Se incluyó a los pacientes con diagnóstico clínico de epilepsia, con dos asistencias a través de telemedicina, que tuvieran seguimiento durante al menos seis meses durante la situación de normalidad previa a la pandemia por COVID-19 y dos consultas presenciales durante ese mismo período. Resultados. Se incluyó a 115 pacientes. La media de edad fue de 29 años, el 53% fueron varones, el 52,2% con epilepsia focal, el 58,3% de etiología estructural y el 57,4% presentaba epilepsia de difícil control. La media de crisis preconfinamiento fue de 9,73/mes y de 6,54/mes durante el confinamiento. El número de pacientes libres de crisis fue mayor al final del confinamiento respecto a la fase preconfinamiento, 54 frente a 45/115. Conclusiones. La telemedicina es una estrategia de mucha utilidad en la monitorización de la evolución, el control evolutivo y los cambios terapéuticos en pacientes epilépticos a corto y medio plazo. La reducción de la frecuencia de crisis puede mantenerse a medio plazo, no sólo a corto plazo como se corroboró en estudios previos. La telemedicina permite acceder a prácticamente la totalidad de los pacientes y realizar un seguimiento más cercano.


Assuntos
COVID-19/epidemiologia , Epilepsia/tratamento farmacológico , Pandemias , Consulta Remota/estatística & dados numéricos , SARS-CoV-2 , Centros de Atenção Terciária/estatística & dados numéricos , Adolescente , Adulto , Idoso , Anticonvulsivantes/uso terapêutico , Criança , Pré-Escolar , Gerenciamento Clínico , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsia Resistente a Medicamentos/epidemiologia , Epilepsias Parciais/tratamento farmacológico , Epilepsias Parciais/epidemiologia , Epilepsia/epidemiologia , Feminino , Guatemala/epidemiologia , Fechamento de Instituições de Saúde , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Aplicativos Móveis , Visita a Consultório Médico/estatística & dados numéricos , Utilização de Procedimentos e Técnicas/estatística & dados numéricos , Consulta Remota/tendências , Estudos Retrospectivos , Convulsões/epidemiologia , Convulsões/prevenção & controle , Telefone , Centros de Atenção Terciária/organização & administração , Resultado do Tratamento , Comunicação por Videoconferência , Adulto Jovem
15.
Evol Ecol ; 34(3): 339-359, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508375

RESUMO

Mutations can occur throughout the virus genome and may be beneficial, neutral or deleterious. We are interested in mutations that yield a C next to a G, producing CpG sites. CpG sites are rare in eukaryotic and viral genomes. For the eukaryotes, it is thought that CpG sites are rare because they are prone to mutation when methylated. In viruses, we know less about why CpG sites are rare. A previous study in HIV suggested that CpG-creating transition mutations are more costly than similar non-CpG-creating mutations. To determine if this is the case in other viruses, we analyzed the allele frequencies of CpG-creating and non-CpG-creating mutations across various strains, subtypes, and genes of viruses using existing data obtained from Genbank, HIV Databases, and Virus Pathogen Resource. Our results suggest that CpG sites are indeed costly for most viruses. By understanding the cost of CpG sites, we can obtain further insights into the evolution and adaptation of viruses.

16.
Neuroscience ; 159(1): 283-95, 2009 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-19141314

RESUMO

Recent demonstrations that positive modulators of AMPA-type glutamate receptors (ampakines) increase neuronal brain-derived neurotrophic factor (BDNF) expression have suggested a novel strategy for treating neurodegenerative diseases. However, reports that AMPA and BDNF receptors are down-regulated by prolonged activation raise concerns about the extent to which activity-induced increases in BDNF levels can be sustained without compromising glutamate receptor function. The present study constitutes an initial test of whether ampakines can cause enduring increases in BDNF content and signaling without affecting AMPA receptor (AMPAR) expression. Prolonged (12-24 h) treatment with the ampakine CX614 reduced AMPAR subunit (glutamate receptor subunit (GluR) 1-3) mRNA and protein levels in cultured rat hippocampal slices whereas treatment with AMPAR antagonists had the opposite effects. The cholinergic agonist carbachol also depressed GluR1-3 mRNA levels, suggesting that AMPAR down-regulation is a global response to extended periods of elevated neuronal activity. Analyses of time courses and thresholds indicated that BDNF expression is influenced by lower doses of, and shorter treatments with, the ampakine than is AMPAR expression. Accordingly, daily 3 h infusions of CX614 chronically elevated BDNF content with no effect on GluR1-3 concentrations. Restorative deconvolution microscopy provided the first evidence that chronic up-regulation of BDNF is accompanied by increased activation of the neurotrophin's TrkB-Fc receptor at spine synapses. These results show that changes in BDNF and AMPAR expression are dissociable and that up-regulation of the former leads to enhanced trophic signaling at excitatory synapses. These findings are encouraging with regard to the feasibility of using ampakines to tonically enhance BDNF-dependent functions in adult brain.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Oxazinas/farmacologia , Receptores de AMPA/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Analgésicos não Narcóticos/farmacologia , Análise de Variância , Animais , Animais Recém-Nascidos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Carbacol/farmacologia , Relação Dose-Resposta a Droga , Hipocampo/citologia , Neurônios/citologia , Subunidades Proteicas/efeitos dos fármacos , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptor trkB/genética , Receptor trkB/metabolismo , Receptores de AMPA/metabolismo , Transdução de Sinais/fisiologia , Estatísticas não Paramétricas , Sinapses/metabolismo , Fatores de Tempo , Técnicas de Cultura de Tecidos , Regulação para Cima/fisiologia
17.
Nat Commun ; 10(1): 3135, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31316061

RESUMO

Sandwich complexes are an indispensable part of organometallic chemistry, which is becoming increasingly important in the field of lanthanide-based single molecule magnets. Herein, a fundamental class of pure sandwich complexes, [(η9-C9H9)Ln(η8-C8H8)] (Ln=Nd, Sm, Dy, Er), is reported. These neutral and sandwiched lanthanide compounds exclusively contain fully π-coordinated coplanar eight and nine membered CH rings. The magnetic properties of these compounds are investigated, leading to the observation of slow relaxation of the magnetization, including open hysteresis loops up to 10 K for the Er(III) analogue. Fast relaxation of the magnetization is likewise observed near zero field, a highly important characteristic for quantum information processing schemes. Our synthetic strategy is straightforward and utilizes the reaction of [(η8-C8H8)LnI(thf)n] complexes with [K(C9H9)]. Although all compounds are fully characterized, structural details of the title compounds can also be deduced by Raman spectroscopy only.

18.
Kidney Int ; 73(4): 391-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18094682

RESUMO

The recent research findings concerning syndromes of muscle wasting, malnutrition, and inflammation in individuals with chronic kidney disease (CKD) or acute kidney injury (AKI) have led to a need for new terminology. To address this need, the International Society of Renal Nutrition and Metabolism (ISRNM) convened an expert panel to review and develop standard terminologies and definitions related to wasting, cachexia, malnutrition, and inflammation in CKD and AKI. The ISRNM expert panel recommends the term 'protein-energy wasting' for loss of body protein mass and fuel reserves. 'Kidney disease wasting' refers to the occurrence of protein-energy wasting in CKD or AKI regardless of the cause. Cachexia is a severe form of protein-energy wasting that occurs infrequently in kidney disease. Protein-energy wasting is diagnosed if three characteristics are present (low serum levels of albumin, transthyretin, or cholesterol), reduced body mass (low or reduced body or fat mass or weight loss with reduced intake of protein and energy), and reduced muscle mass (muscle wasting or sarcopenia, reduced mid-arm muscle circumference). The kidney disease wasting is divided into two main categories of CKD- and AKI-associated protein-energy wasting. Measures of chronic inflammation or other developing tests can be useful clues for the existence of protein-energy wasting but do not define protein-energy wasting. Clinical staging and potential treatment strategies for protein-energy wasting are to be developed in the future.


Assuntos
Caquexia/classificação , Nefropatias/complicações , Desnutrição/classificação , Síndrome de Emaciação/classificação , Doença Aguda , Caquexia/diagnóstico , Caquexia/etiologia , Doença Crônica , Metabolismo Energético , Humanos , Inflamação/classificação , Inflamação/diagnóstico , Inflamação/etiologia , Desnutrição/diagnóstico , Desnutrição/etiologia , Proteínas/metabolismo , Síndrome , Terminologia como Assunto , Síndrome de Emaciação/diagnóstico , Síndrome de Emaciação/etiologia
19.
Parasitology ; 135(5): 547-53, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18426617

RESUMO

In Colombia, Plasmodium resistance to antimalarials such as chloroquine and antifolates is a serious problem. As a result, the national Colombian health authorities are monitoring the efficacy of alternative drugs and schemes. The study of genetic polymorphisms related with drug resistance is required in the region. In vitro responses to chloroquine, quinine, mefloquine, amodiaquine, desethylamodiaquine, artesunate and dihydroartesunate were carried out by HRP ELISA. SNP analysis in Pfcrt and Pfmdr1 genes was performed by PCR-RFLP in 77 samples from the North West region of Colombia. In vitro resistance to chloroquine was high (74%), followed by mefloquine (30%) and desethylamodiaquine (30%). A positive correlation between the IC(50) of paired drugs was also detected. The allele Pfmdr1 N86 (wild) was present in 100% of the samples and 1246Y (mutant) in 92%. However, their presence did not correlate with in vitro drug resistance. Presence of the mutations K76T and N75E in Pfcrt was confirmed in all samples. Analysis of 4 codons (72, 74, 75 and 76) in pfcrt confirmed the presence of the haplotypes CMET in 91% and SMET in 9% of the samples.


Assuntos
Antimaláricos/farmacologia , Resistência a Medicamentos/genética , Proteínas de Membrana Transportadoras/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Plasmodium falciparum/efeitos dos fármacos , Polimorfismo de Nucleotídeo Único , Proteínas de Protozoários/genética , Amodiaquina/análogos & derivados , Amodiaquina/farmacologia , Animais , Cloroquina/farmacologia , Colômbia/epidemiologia , Humanos , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Mefloquina/farmacologia , Testes de Sensibilidade Parasitária , Plasmodium falciparum/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
20.
Clin Transl Oncol ; 20(1): 16-21, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29058264

RESUMO

The SEOM/GEINO clinical guidelines provide recommendations for radiological, and molecular diagnosis, treatment and follow-up of adult patients with anaplastic gliomas (AG). We followed the 2016 WHO classification which specifies the major diagnostic/prognostic and predictive value of IDH1/IDH2 missense mutations and 1p/19q codeletions in AG. The diagnosis of anaplastic oligoastrocytoma is discouraged. Surgery, radiotherapy and chemotherapy with PCV or TMZ are the first-line standard of care for AG with slight modifications according to molecular variables. A multidisciplinary team is highly recommended in the management of these tumors.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Glioma/diagnóstico , Glioma/terapia , Humanos
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