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1.
Neuroimage ; 285: 120498, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38135170

RESUMO

Cortical electro-encephalography (EEG) served as the clinical reference for monitoring unconsciousness during general anesthesia. The existing EEG-based monitors classified general anesthesia states as underdosed, adequate, or overdosed, lacking predictive power due to the absence of transition phases among these states. In response to this limitation, we undertook an analysis of the EEG signal during isoflurane-induced general anesthesia in mice. Adopting a data-driven approach, we applied signal processing techniques to track θ- and δ-band dynamics, along with iso-electric suppressions. Combining this approach with machine learning, we successfully developed an automated algorithm. The findings of our study revealed that the dampening of the δ-band occurred several minutes before the onset of significant iso-electric suppression episodes. Furthermore, a distinct γ-frequency oscillation was observed, persisting for several minutes during the recovery phase subsequent to isoflurane-induced overdose. As a result of our research, we generated a map summarizing multiple brain states and their transitions, offering a tool for predicting and preventing overdose during general anesthesia. The transition phases identified, along with the developed algorithm, have the potential to be generalized, enabling clinicians to prevent inadequate anesthesia and, consequently, tailor anesthetic regimens to individual patients.


Assuntos
Isoflurano , Humanos , Camundongos , Animais , Isoflurano/farmacologia , Eletroencefalografia , Anestesia Geral , Inconsciência , Encéfalo
2.
Oncologist ; 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970465

RESUMO

On August 11, 2022, FDA granted accelerated approval to fam-trastuzumab deruxtecan-nxki (DS-8201a, T-DXd, ENHERTU, Daiichi Sankyo) for adult patients with unresectable or metastatic non-small cell lung cancer (NSCLC) whose tumors have activating human epidermal growth factor receptor 2 (HER2) mutations, as detected by an FDA-approved test, and who have received a prior systemic therapy. The approval was based on a prespecified interim analysis of DESTINY-Lung02 (Study U206), a multi-center, randomized, dose-optimization trial in patients with NSCLC harboring activating HER2-mutations. At the approved dose of 5.4 mg/kg given intravenously every 3 weeks, the overall response rate (ORR) was 58% (95% confidence interval [CI]: 43, 71). The median duration of response was 8.7 months (95% CI: 7.1, not estimable). These results were consistent with response rates observed at the 6.4 mg/kg dose level. The most common (≥ 20%) adverse reactions were nausea, constipation, decreased appetite, vomiting, fatigue, and alopecia. The rate of interstitial lung disease (ILD) or pneumonitis was 6% at the 5.4 mg/kg dose level and 14% at the 6.4 mg/kg dose level. In the setting of similar efficacy and reduced toxicity, approval was granted for the 5.4 mg/kg dose level. The applicant conducted a randomized, dose-optimization study with guidance from the FDA Oncology Center of Excellence's Project Optimus. This is the first approval of a targeted therapy for HER2-mutated NSCLC.

3.
Nature ; 517(7536): 571-5, 2015 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-25533953

RESUMO

The plant cell wall is an important factor for determining cell shape, function and response to the environment. Secondary cell walls, such as those found in xylem, are composed of cellulose, hemicelluloses and lignin and account for the bulk of plant biomass. The coordination between transcriptional regulation of synthesis for each polymer is complex and vital to cell function. A regulatory hierarchy of developmental switches has been proposed, although the full complement of regulators remains unknown. Here we present a protein-DNA network between Arabidopsis thaliana transcription factors and secondary cell wall metabolic genes with gene expression regulated by a series of feed-forward loops. This model allowed us to develop and validate new hypotheses about secondary wall gene regulation under abiotic stress. Distinct stresses are able to perturb targeted genes to potentially promote functional adaptation. These interactions will serve as a foundation for understanding the regulation of a complex, integral plant component.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Redes Reguladoras de Genes/genética , Fatores de Transcrição/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , DNA de Plantas/genética , DNA de Plantas/metabolismo , Fatores de Transcrição E2F/metabolismo , Retroalimentação , Regulação da Expressão Gênica no Desenvolvimento/genética , Deficiências de Ferro , Especificidade de Órgãos , Regiões Promotoras Genéticas/genética , Reprodutibilidade dos Testes , Salinidade , Fatores de Tempo , Xilema/genética , Xilema/crescimento & desenvolvimento , Xilema/metabolismo
4.
J Mol Liq ; 340: 117284, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34421159

RESUMO

The COVID-19 pandemic has accelerated the study of the potential of multi-target drugs (MTDs). The mixture of homologues called ivermectin (avermectin-B1a + avermectin-B1b) has been shown to be a MTD with potential antiviral activity against SARS-CoV-2 in vitro. However, there are few reports on the effect of each homologue on the flexibility and stiffness of proteins associated with COVID-19, described as ivermectin targets. We observed that each homologue was stably bound to the proteins studied and was able to induce detectable changes with Elastic Network Models (ENM). The perturbations induced by each homologue were characteristic of each compound and, in turn, were represented by a disruption of native intramolecular networks (interactions between residues). The homologues were able to slightly modify the conformation and stability of the connection points between the Cα atoms of the residues that make up the structural network of proteins (nodes), compared to free proteins. Each homologue was able to modified differently the distribution of quasi-rigid regions of the proteins, which could theoretically alter their biological activities. These results could provide a biophysical-computational view of the potential MTD mechanism that has been reported for ivermectin.

5.
Opt Express ; 27(4): 4140-4146, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30876034

RESUMO

We report on multidimensional spectroscopy in the mid-infrared, performed using a calomel-based acousto-optic programmable dispersive filter. Although the associated spectral resolution is currently not as good as what has been previously reported using time-domain interferometers or other pulse-shaping technologies, the extreme compactness of the calomel crystal allows a straightforward implementation in a pre-existing pump-probe setup. Furthermore, the frequency-domain approach allows easy measurement of 2D slices of the multidimensional spectrum associated with a given pump frequency. We demonstrate our method with the measurement of the mid-infrared spectrum of carboxy-hemoglobin in three spectro-temporal dimensions.

6.
Lupus ; 28(2): 249-252, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30616452

RESUMO

Childhood-onset systemic lupus erythematosus (cSLE) is a chronic inflammatory multisystem autoimmune disease that requires multiple differential diagnoses. Munchausen by proxy syndrome (MBPS) is a form of child abuse, where a caregiver intentionally creates a medical history and induces or fabricates signs or disease in a patient. To our knowledge, there is no case report of MBPS mimicking cSLE diagnosis. We reported herein a 9-year-old male patient, with a history of multiple hospitalizations due to seizures with altered levels of consciousness. The mother reported malar rash, photosensitivity, alopecia, arthralgia, arterial hypertension, macroscopic hematuria, seizure and positive antinuclear antibodies. In the other service, he was treated with intravenous methylprednisolone, prednisone and mycophenolate mofetil. At 8 years and 8 months, he was admitted to our tertiary center with history of fever and macroscopic hematuria. Laboratory examinations were normal, including negative for antinuclear antibodies, anti-double stranded DNA, anticardiolipin, anti-Ro/SSA, anti-La/SSB, anti-RNP and anti-Sm antibodies. Multiple urine cultures revealed the presence of Enterococcus faecium, Acinetobacter sp., Stenotrophomonas maltophilia and Serratia marcescens, without any association with pyuria. At 8 years and 9 months, he was readmitted at emergency room with history of severe fever, headache, vomiting, photophobia, phonophobia and dizziness. The physical examination showed agitation, confusion, ataxic gait, slurred speech, horizontal nystagmus, painful facial expressions, tachycardia and weight loss. Brain magnetic resonance angiography and cerebrospinal fluid analysis were normal. During hospitalization, he had an acute episode of epistaxis and otalgia with excoriation in the auditory canal. At that moment, the suspicion of MBPS mimicking cSLE was raised and phenytoin intoxication was confirmed (peak phenytoin concentration was 45.4 mcg/mL, therapeutic range 10-20 mcg/mL). The mother and the patient were immediately separated, and she was replaced by another legal guardian. One week later, the neurological and other signs and symptoms were completely resolved. The child was placed under paternal custody with a court order and moved to another state. After that, the mother reported phenytoin use for her child and was referred to psychiatric follow-up. In conclusion, the first case of MBPS mimicking cSLE, resulting in multiple unnecessary examinations and treatments with delayed diagnosis was reported.


Assuntos
Síndrome de Munchausen Causada por Terceiro/diagnóstico , Idade de Início , Criança , Diagnóstico Tardio , Diagnóstico Diferencial , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Masculino , Procedimentos Desnecessários
7.
Org Biomol Chem ; 14(14): 3506-9, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26991839

RESUMO

The interactions between chondroitin sulfate (CS) and a wide number of proteins modulate important biological processes. Here, the binding properties to midkine and pleiotrophin of sulfated, fully protected intermediates, typically obtained in the chemical synthesis of CS oligosaccharides, were tested for the first time. Using a fluorescence polarization competition experiment, we discovered that these synthetic precursors strongly bound these two closely related cytokines involved in cancer and inflammation. The relative binding affinities of these intermediates were significantly higher than those displayed by the corresponding fully deprotected oligosaccharides, indicating that the presence of hydrophobic protecting groups strongly enhanced the binding of CS-like derivatives to midkine. These compounds offer novel opportunities for the development of potent inhibitors/activators of CS-protein interactions with potential therapeutic applications.


Assuntos
Sulfatos de Condroitina/metabolismo , Citocinas/metabolismo , Sítios de Ligação , Polarização de Fluorescência , Interações Hidrofóbicas e Hidrofílicas , Midkina
8.
J Appl Microbiol ; 121(2): 435-44, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27225974

RESUMO

AIMS: The aim of this study was to investigate the potential of aureocin A53, a staphylococcal antimicrobial peptide, for improving food safety. METHODS AND RESULTS: The antimicrobial activity of aureocin A53 against strains of Listeria monocytogenes isolated from food was tested and the bacteriocin proved to be bactericidal and bacteriolytic against the listerial strains. Aureocin A53 was neither toxic to eukaryotic cell lines nor haemolytic against sheep erythrocytes. It also exhibited a remarkable stability during storage at different temperatures and sensitivity to both simulated gastric juice and bile salts. When the antibacterial activity of aureocin A53 (256 AU ml(-1) ) was tested in skimmed milk artificially inoculated with a L. monocytogenes strain (1·0 × 10(4)  CFU ml(-1) ) isolated from food, during storage at 4°C, the bacteriocin reduced the viable counts by 7·7-log10 units up to 7 days of incubation, when compared with the controls not treated with the bacteriocin. CONCLUSIONS: Aureocin A53 exhibited several features considered important for biopreservation and remained fully active in a food matrix. SIGNIFICANCE AND IMPACT OF THE STUDY: Taken together, the results confirmed that aureocin A53 has potential to be used as a food preservative, representing an alternative to the use of nisin in biopreservation of dairy products.


Assuntos
Antibacterianos/farmacologia , Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Leite/microbiologia , Peptídeos/farmacologia , Animais , Peptídeos Catiônicos Antimicrobianos , Conservação de Alimentos/instrumentação , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/isolamento & purificação , Ovinos
9.
J Sports Med Phys Fitness ; 54(2): 225-31, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24509995

RESUMO

AIM: Strenuous exercise can enhance plasma levels of pro- and anti-inflammatory cytokines. Increases in plasma tumor necrosis factor-alpha (TNF-α) are followed rapidly by a rise in its natural inhibitors, soluble TNF receptors (sTNFRs). These inhibitors likely prevent an over-response to the cytokine. Aims of the present study were: 1) analyze plasma sTNFR1 at different time-points in response to a strenuous off-road cycling competition; 2) evaluate whether plasma levels of sTNFR1 correlate to increased blood lactate levels on completion of the exercise. METHODS: Eight trained off-road cyclists took part in this study and the data collection occurred during an official off-road race. Blood samples were collected pre-race, immediately post-race, and 1 h, 2 h and 24 h during the recovery period, for plasma sTNFR1 and blood lactate determination. RESULTS: Increase in sTNFR1 plasma levels were observed immediately post-race, 1 h and 2 h post-race (P<0.01), returning to baseline levels at the end of the recovery period (24 h). Significant correlation between plasma levels of sTNFR1 and blood lactate concentration were observed at the end of the race (r=0.925; P<0.001). CONCLUSION: An off-road cycling race stimulated an increase in plasma sTNFR1 and this anti-inflammatory molecule was positively correlated to blood lactate concentration. This result reinforces the view that exercise intensity influences the increase in plasma anti-inflammatory molecules.


Assuntos
Ciclismo/fisiologia , Comportamento Competitivo , Esforço Físico/fisiologia , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Humanos , Lactatos/sangue , Masculino , Volume Plasmático , Inquéritos e Questionários , Adulto Jovem
10.
Front Neurol ; 15: 1349501, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585358

RESUMO

Introduction: Parents of children with neuromuscular diseases experience multiple difficulties in their daily lives that affect their physical and psychological health. The risk factors for these health issues have not been sufficiently investigated. Therefore, the aim of this study was to analyze the potential predictors of overload in these parents, including QoL, somatic symptomatology, life satisfaction, psychological adjustment and certain sociodemographic variables. Methods: A cross-sectional research study was conducted among parents who are caregivers for children with NMD in Spain. A convenience sample of 110 parents who were contacted by associations and hospitals was used. Variables were evaluated using the sociodemographic questionnaire, CarerQol-7D, PHQ-15, Barthel Index, Psychological Adaptation Scale, Zarit Overload Scale and Satisfaction with Life Scale. Results: One of the most relevant findings of the present study is the identification of 3 overload groups (mild to moderate, moderate to severe, and severe overload) based on life satisfaction and somatic symptom scores within the predictive model of the discriminate analysis. Wilk's lambda of the discriminant function was 0.568, χ2 (2, n = 55) = 8.815, p < 0.001. Discussion: This study presents a model that reveals the influence of unemployment, having a child with a severe level of dependency, the presence of somatic symptomatology and life satisfaction on caregiver overload. Likewise, the caregiver's self-esteem could be a protective factor against overload.

11.
Rev Neurol ; 78(11): 295-305, 2024 Jun 01.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-38813787

RESUMO

AIM: To determine post-surgical cognitive risk and associated factors according to lesion location in a sample of patients evaluated for epilepsy surgery with Wada test at the Fundacion Instituto Neurologico de Colombia. MATERIALS AND METHODS: An observational, retrospective, analytical study was completed in patients with drug-resistant temporal lobe epilepsy candidates for epilepsy surgery treated from 2001 to 2021, who completed the Wada test as part of the pre-surgical evaluation. A descriptive analysis of sociodemographic, clinical, imaging and neuropsychological variables was completed; a multivariate logistic regression was performed analyzing factors associated with resection risk in patients with left lesions. RESULTS A total of 369 patients were included, 54.74% of the cases were women, with a median age of seizure onset of 11 years. 92.66% of the cases had lesional epilepsy and 68.56% were secondary to hippocampal sclerosis. Left hemisphere was the most frequently affected (65.68%) being dominant for memory and language in most of the patients with a proportion of 42.82% and 81.3%, respectively. The median functional adequacy was 43.75 (IQR 0-75) and the functional reserve was 75 (IQR 25 -93.75). In 104 patients, the Wada test determined a resection risk. In patients with a left lesion, it was found that functional reserve (PRadjusted 0.99, CI 95% 0.9997-0.9998) and having a right hemispheric dominance for memory (PRadjusted 0.92, CI 95% 0.547-0.999) were protective factors for post-surgical resection risk. CONCLUSION: Wada test is a useful tool for surgical decision-making in patients with drug-resistant temporal lobe epilepsy. When considering cognitive risk, components such as memory dominance and functional reserve should be considered as protective factors for postsurgical cognitive function preservation in patients with left lesions.


TITLE: Evaluación de la memoria y el lenguaje mediante el test de Wada en pacientes candidatos a cirugía de epilepsia.Objetivo. Determinar el riesgo cognitivo posquirúrgico y factores asociados según la localización de la lesión en una muestra de pacientes evaluados para cirugía de epilepsia con el test de Wada en la Fundación Instituto Neurológico de Colombia. Materiales y métodos. Se realizó un estudio observacional, retrospectivo y analítico en pacientes con epilepsia farmacorresistente del lóbulo temporal candidatos a cirugía de epilepsia tratados entre 2001 y 2021, que completaron el test de Wada como parte de la evaluación prequirúrgica. Se realizó un análisis descriptivo de variables sociodemográficas, clínicas, imagenológicas y neuropsicológicas. Se realizó una regresión logística multivariada analizando factores asociados al riesgo de resección en pacientes con lesiones izquierdas. Resultados. Se incluyó a 369 pacientes, el 54,74% de los casos fueron mujeres, con una mediana de edad de inicio de las convulsiones de 11 años. El 92,66% de los casos presentó epilepsia lesional; de éstos, el 68,56% fue secundario a esclerosis hipocampal. El hemisferio izquierdo fue el más frecuentemente afectado (65,68%), y éste fue dominante para la memoria y el lenguaje en la mayoría de los pacientes, con una proporción del 42,82 y el 81,3%, respectivamente. La mediana de adecuación funcional fue de 43,75 (rango intercuartílico: 0-75) y la reserva funcional de 75 (rango intercuartílico: 25-93,75). En 104 pacientes, el test de Wada determinó un riesgo de resección. En pacientes con lesiones izquierdas se encontró que la reserva funcional (razón de prevalencia ajustada: 0,99; intervalo de confianza al 95%: 0,9997-0,9998) y tener dominancia del hemisferio derecho para la memoria (razón de prevalencia ajustada: 0,92; intervalo de confianza al 95%: 0,547-0,999) fueron factores asociados para determinar el riesgo de resección posquirúrgico en el test de Wada. Conclusión. El test de Wada es una herramienta útil para la toma de decisiones quirúrgicas en pacientes con epilepsia del lóbulo temporal farmacorresistente. Componentes como la dominancia de la memoria y la reserva funcional en el test de Wada deben considerarse como factores que se deben tener en cuenta en la predicción de la preservación de la función cognitiva posquirúrgica en pacientes con lesiones izquierdas.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia do Lobo Temporal , Humanos , Feminino , Masculino , Estudos Retrospectivos , Adulto , Medição de Risco , Epilepsia do Lobo Temporal/cirurgia , Epilepsia Resistente a Medicamentos/cirurgia , Testes Neuropsicológicos , Complicações Pós-Operatórias/etiologia , Adulto Jovem , Adolescente , Criança , Idioma
12.
Anal Biochem ; 443(2): 249-51, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24050966

RESUMO

This work presents a rapid and simple freeze centrifugation method to concentrate dilute protein solutions for detection by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) Coomassie blue staining. Moreover, a simple way to assemble a cryoconcentration device is presented, and its use is discussed. Commercial purified protein standard and an enzyme with high fructosyltransferase (FTase) activity, coming from target fractions obtained by chromatographic separation, were used as an example. FTase, coming directly from the chromatographic fractions, was difficult to view through SDS-PAGE analysis; however, it was easily visualized, and its activity was enhanced, after the application of the freeze centrifugation protocol presented here.


Assuntos
Centrifugação/instrumentação , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas/isolamento & purificação , Animais , Aspergillus/enzimologia , Desenho de Equipamento , Congelamento , Hexosiltransferases/isolamento & purificação , Cavalos
13.
PLoS Comput Biol ; 8(1): e1002349, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22275858

RESUMO

Intrinsic plasticity (IP) is a ubiquitous activity-dependent process regulating neuronal excitability and a cellular correlate of behavioral learning and neuronal homeostasis. Because IP is induced rapidly and maintained long-term, it likely represents a major determinant of adaptive collective neuronal dynamics. However, assessing the exact impact of IP has remained elusive. Indeed, it is extremely difficult disentangling the complex non-linear interaction between IP effects, by which conductance changes alter neuronal activity, and IP rules, whereby activity modifies conductance via signaling pathways. Moreover, the two major IP effects on firing rate, threshold and gain modulation, remain unknown in their very mechanisms. Here, using extensive simulations and sensitivity analysis of Hodgkin-Huxley models, we show that threshold and gain modulation are accounted for by maximal conductance plasticity of conductance that situate in two separate domains of the parameter space corresponding to sub- and supra-threshold conductance (i.e. activating below or above the spike onset threshold potential). Analyzing equivalent integrate-and-fire models, we provide formal expressions of sensitivities relating to conductance parameters, unraveling unprecedented mechanisms governing IP effects. Our results generalize to the IP of other conductance parameters and allow strong inference for calcium-gated conductance, yielding a general picture that accounts for a large repertoire of experimental observations. The expressions we provide can be combined with IP rules in rate or spiking models, offering a general framework to systematically assess the computational consequences of IP of pharmacologically identified conductance with both fine grain description and mathematical tractability. We provide an example of such IP loop model addressing the important issue of the homeostatic regulation of spontaneous discharge. Because we do not formulate any assumptions on modification rules, the present theory is also relevant to other neural processes involving excitability changes, such as neuromodulation, development, aging and neural disorders.


Assuntos
Modelos Neurológicos , Plasticidade Neuronal/fisiologia , Potenciais de Ação/fisiologia , Animais , Simulação por Computador , Rede Nervosa , Análise de Regressão
14.
J Environ Manage ; 131: 103-9, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24157410

RESUMO

Arsenic (As) in groundwater for domestic use poses a worldwide threat to public health, most notably in rural areas. The aims of this study were: first, determine groundwater composition in a mining area in central Mexico (Huautla); second, assess As exposure through human groundwater consumption and; third, develop and test a household filter to obtain drinking water for these rural communities. From the 17th century through the 1990s, mines in the area produced Ag-galena and sphalerite from volcanic rock. Groundwater flooded the mines when they were abandoned due to low silver prices. Local households now use the water to meet domestic needs. Water from the mines was found to have high As content (0.04-0.26 mg L(-1)) and Fe, Mn, Pb and Cd were also above Mexican drinking water standards and WHO guidelines. All the population in the Huautla community was exposed to the metalloid through water used in food preparation. The best As removal was obtained with a filter using oxidized commercial fiber (HCl 2N as oxidant). Concentrations in the effluent were below Mexican drinking water standards (0.025 mg As L(-1) water) during the 105-day (2520 h) filter operation, with a maximum As removal efficiency of 95.4%. The household filter was simple, low-cost and may be very attractive for As removal in rural areas in developing countries.


Assuntos
Arsênio/química , Ferro/química , Aço Inoxidável/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
15.
J Immunother Cancer ; 11(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36796877

RESUMO

In the era of precision oncology, use of circulating tumor DNA (ctDNA) is emerging as a minimally invasive approach for the diagnosis and management of patients with cancer and as an enrichment tool in clinical trials. In recent years, the US Food and Drug Administration has approved multiple ctDNA-based companion diagnostic assays for the safe and effective use of targeted therapies and ctDNA-based assays are also being developed for use with immuno-oncology-based therapies. For early-stage solid tumor cancers, ctDNA may be particularly important to detect molecular residual disease (MRD) to support early implementation of adjuvant or escalated therapy to prevent development of metastatic disease. Clinical trials are also increasingly using ctDNA MRD for patient selection and stratification, with an ultimate goal of improving trial efficiency through use of an enriched patient population. Standardization and harmonization of ctDNA assays and methodologies, along with further clinical validation of ctDNA as a prognostic and predictive biomarker, are necessary before ctDNA may be considered as an efficacy-response biomarker to support regulatory decision making.


Assuntos
DNA Tumoral Circulante , Medicina de Precisão , Estados Unidos , Humanos , Medicina de Precisão/métodos , DNA Tumoral Circulante/genética , Oncologia , Prognóstico , Neoplasia Residual
16.
Cancer Cell ; 41(4): 807-817.e6, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-37037617

RESUMO

Patients with short telomere syndromes (STS) are predisposed to developing cancer, believed to stem from chromosome instability in neoplastic cells. We tested this hypothesis in a large cohort assembled over the last 20 years. We found that the only solid cancers to which patients with STS are predisposed are squamous cell carcinomas of the head and neck, anus, or skin, a spectrum reminiscent of cancers seen in patients with immunodeficiency. Whole-genome sequencing showed no increase in chromosome instability, such as translocations or chromothripsis. Moreover, STS-associated cancers acquired telomere maintenance mechanisms, including telomerase reverse transcriptase (TERT) promoter mutations. A detailed study of the immune status of patients with STS revealed a striking T cell immunodeficiency at the time of cancer diagnosis. A similar immunodeficiency that impaired tumor surveillance was documented in mice with short telomeres. We conclude that STS patients' predisposition to solid cancers is due to T cell exhaustion rather than autonomous defects in the neoplastic cells themselves.


Assuntos
Carcinoma de Células Escamosas , Telomerase , Animais , Camundongos , Telômero/genética , Telômero/metabolismo , Carcinoma de Células Escamosas/genética , Instabilidade Cromossômica , Mutação , Telomerase/genética , Telomerase/metabolismo , Linfócitos T/metabolismo
17.
Behav Neurol ; 2023: 9681740, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36815863

RESUMO

The early introduction of a low phenylalanine (Phe) diet has been demonstrated to be the most successful treatment in subjects with phenylketonuria (PKU), especially for preventing severe cognitive and neurological damages. However, it still concerns that even if treated in the first months of life with supplements and following a diet, they can show slight scores below people without PKU in neuropsychological assignments. We investigated 20 adults with classical PKU aged 19-48 years (mean age 29 years) and 20 heathy controls matched by age, gender, and years of education. Patients and controls were assessed with an extended neuropsychological battery, as well as psychological aspects and quality of life, also the last Phe level result was obtained. Results showed that the most affected cognitive domains are processing speed, executive functioning, memory, and also theory of mind, but very well-preserved verbal fluency, language, and visuospatial functioning. In quality of life, some significant results were seen specially in anxiety of Phe levels, anxiety of Phe levels during pregnancy, guilt if poor adherence to supplements, and if dietary protein restriction not followed. No significant results were obtained for the psychological variables. In conclusion, it has been shown that a combination of a low Phe diet, supplement intake, and keeping Phe levels in a low range seems appropriate to have the most normal and alike cognitive performance to persons without PKU.


Assuntos
Fenilcetonúrias , Qualidade de Vida , Humanos , Adulto , Fenilalanina , Cognição , Fenilcetonúrias/metabolismo , Fenilcetonúrias/psicologia , Função Executiva
18.
Anal Biochem ; 426(1): 4-12, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22475503

RESUMO

One of the recurrent methodological problems in preparative biochemical work is the concentration of dilute protein solutions, including culture supernatants resulting from biotechnological processes. A procedure was developed to concentrate enzymes by a novel cryoconcentration system. This approach includes a new device that facilitates the sample freezing and the subsequent solute elution from the frozen matrix by centrifugation. The optimal centrifugation conditions for this cryoconcentration system were obtained using whey protein solution as a model. The procedure was applied to concentrate dilute solutions of commercial pectinase, measuring the endopolygalacturonase (EPG) activity of this enzyme in the concentrate by a method based on the on-line torque measurement, and of recombinant fructan:fructan 1-fructosyltransferase (1-FFT) protein of Pichia pastoris from a culture in a bioreactor, as an expression system. The optimal centrifugation speed, time, and temperature were 6150 g, 20 min, and 4 °C, respectively. The concentration factors for the dilute protein solutions were 9.2-, 11.2-, and 17.1-fold for 1-FFT, whey, and commercial pectinase, respectively. Recoveries ranged from 87% to 93%. The procedure allowed concentrating proteins efficiently without affecting their enzymatic activity.


Assuntos
Hexosiltransferases/metabolismo , Poligalacturonase/metabolismo , Centrifugação , Diálise , Congelamento , Hexosiltransferases/genética , Hexosiltransferases/isolamento & purificação , Pichia/metabolismo , Poligalacturonase/isolamento & purificação , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
19.
Heliyon ; 8(4): e09329, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35520622

RESUMO

An analysis of the scientific production of Ecuador is performed by means of the composite indicator computed for Ecuador-based authors as compared to their counterparts of other South American countries. The dataset employed was obtained from the Databricks platform of the ELSEVIER's International Center for Science Research, ICSR. Therefore, this analysis is limited to the metadata of the documents published in journals indexed in SCOPUS. Comparison of the results obtained for two decades: 2001-2010 and 2011-2020 showed that the number of Ecuador-based researchers has significantly increased in different areas of knowledge. Moreover, comparison between the total number of authors that worked in Ecuador at any given year of the 2011-2020 period and the number of authors that are still working in this country up to the date of the data extraction (i.e., June 2021) showed an average of ∼68% of permanency. Analysis of the percentage distribution in terms of range quarters of the composite indicator (i.e., Q4: 0-1.5, Q3: 1.5-3.0, Q2: 3.0-4.5, and Q1: 4.5-6.0) showed that nearly the totality of the Ecuador-based researchers has composite indicators that lay in the Q4 and Q3 ranges for all the scientific fields considered. The latter was observed to be an effect of the scientific impact of South American countries, with larger investments in science and technology in comparison to Ecuador (i.e., Argentina, Brazil, and Chile). Exclusion of this group of countries in the calculation of the composite indicator of Ecuador-based authors resulted in a noticeable increment of scientists with composite indicators within Q2. Finally, our results suggest, in agreement with previous studies, a correlation between the sustained growth of scientific productivity in the decade 2011-2020 with the scientific programs and policies created by the state, where the initiative of scientific culture is shown as a strategy for growth and development.

20.
Comput Biol Med ; 142: 105245, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35077937

RESUMO

Cellular susceptibility to SARS-CoV-2 infection in the respiratory tract has been associated with the ability of the virus to interact with potential receptors on the host membrane. We have modeled viral dynamics by simulating various cellular systems and artificial conditions, including macromolecular crowding, based on experimental and transcriptomic data to infer parameters associated with viral growth and predict cell susceptibility. We have accomplished this based on the type, number and level of expression of the angiotensin-converting enzyme 2 (ACE2), transmembrane serine 2 (TMPRSS2), basigin2 (CD147), FURIN protease, neuropilin 1 (NRP1) or other less studied candidate receptors such as heat shock protein A5 (HSPA5) and angiotensin II receptor type 2 (AGTR2). In parallel, we studied the effect of simulated artificial environments on the accessibility to said proposed receptors. In addition, viral kinetic behavior dependent on the degree of cellular susceptibility was predicted. The latter was observed to be more influenced by the type of proteins and expression level, than by the number of potential proteins associated with the SARS CoV-2 infection. We predict a greater theoretical propensity to susceptibility in cell lines such as NTERA-2, SCLC-21H, HepG2 and Vero6, and a lower theoretical propensity in lines such as CaLu3, RT4, HEK293, A549 and U-251MG. An important relationship was observed between expression levels, protein diffusivity, and thermodynamically favorable interactions between host proteins and the viral spike, suggesting potential sites of early infection other than the lungs. This research is expected to stimulate future quantitative experiments and promote systematic investigation of the effect of crowding presented here.


Assuntos
COVID-19 , Células HEK293 , Humanos , SARS-CoV-2 , Internalização do Vírus
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