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1.
Nature ; 597(7878): 732-737, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34526717

RESUMO

Epidermal growth factor receptor (EGFR) mutations typically occur in exons 18-21 and are established driver mutations in non-small cell lung cancer (NSCLC)1-3. Targeted therapies are approved for patients with 'classical' mutations and a small number of other mutations4-6. However, effective therapies have not been identified for additional EGFR mutations. Furthermore, the frequency and effects of atypical EGFR mutations on drug sensitivity are unknown1,3,7-10. Here we characterize the mutational landscape in 16,715 patients with EGFR-mutant NSCLC, and establish the structure-function relationship of EGFR mutations on drug sensitivity. We found that EGFR mutations can be separated into four distinct subgroups on the basis of sensitivity and structural changes that retrospectively predict patient outcomes following treatment with EGFR inhibitors better than traditional exon-based groups. Together, these data delineate a structure-based approach for defining functional groups of EGFR mutations that can effectively guide treatment and clinical trial choices for patients with EGFR-mutant NSCLC and suggest that a structure-function-based approach may improve the prediction of drug sensitivity to targeted therapies in oncogenes with diverse mutations.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Afatinib/uso terapêutico , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Reposicionamento de Medicamentos , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/genética , Éxons , Feminino , Humanos , Neoplasias Pulmonares/genética , Camundongos , Simulação de Acoplamento Molecular , Mutação , Relação Estrutura-Atividade
2.
Proc Natl Acad Sci U S A ; 120(28): e2220276120, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37406091

RESUMO

Epithelial-to-mesenchymal transition (EMT) underlies immunosuppression, drug resistance, and metastasis in epithelial malignancies. However, the way in which EMT orchestrates disparate biological processes remains unclear. Here, we identify an EMT-activated vesicular trafficking network that coordinates promigratory focal adhesion dynamics with an immunosuppressive secretory program in lung adenocarcinoma (LUAD). The EMT-activating transcription factor ZEB1 drives exocytotic vesicular trafficking by relieving Rab6A, Rab8A, and guanine nucleotide exchange factors from miR-148a-dependent silencing, thereby facilitating MMP14-dependent focal adhesion turnover in LUAD cells and autotaxin-mediated CD8+ T cell exhaustion, indicating that cell-intrinsic and extrinsic processes are linked through a microRNA that coordinates vesicular trafficking networks. Blockade of ZEB1-dependent secretion reactivates antitumor immunity and negates resistance to PD-L1 immune checkpoint blockade, an important clinical problem in LUAD. Thus, EMT activates exocytotic Rabs to drive a secretory program that promotes invasion and immunosuppression in LUAD.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , MicroRNAs , Humanos , Linhagem Celular Tumoral , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Neoplasias Pulmonares/genética , Adenocarcinoma de Pulmão/genética , MicroRNAs/genética , Terapia de Imunossupressão , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Movimento Celular/genética
3.
Brief Bioinform ; 24(4)2023 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-37337757

RESUMO

The T-cell receptor (TCR) repertoire is highly diverse among the population and plays an essential role in initiating multiple immune processes. TCR sequencing (TCR-seq) has been developed to profile the T cell repertoire. Similar to other high-throughput experiments, contamination can happen during several steps of TCR-seq, including sample collection, preparation and sequencing. Such contamination creates artifacts in the data, leading to inaccurate or even biased results. Most existing methods assume 'clean' TCR-seq data as the starting point with no ability to handle data contamination. Here, we develop a novel statistical model to systematically detect and remove contamination in TCR-seq data. We summarize the observed contamination into two sources, pairwise and cross-cohort. For both sources, we provide visualizations and summary statistics to help users assess the severity of the contamination. Incorporating prior information from 14 existing TCR-seq datasets with minimum contamination, we develop a straightforward Bayesian model to statistically identify contaminated samples. We further provide strategies for removing the impacted sequences to allow for downstream analysis, thus avoiding any need to repeat experiments. Our proposed model shows robustness in contamination detection compared with a few off-the-shelf detection methods in simulation studies. We illustrate the use of our proposed method on two TCR-seq datasets generated locally.


Assuntos
Receptores de Antígenos de Linfócitos T , Linfócitos T , Humanos , Teorema de Bayes , Receptores de Antígenos de Linfócitos T/genética , Modelos Estatísticos , Sequenciamento de Nucleotídeos em Larga Escala/métodos
4.
Emerg Infect Dis ; 30(3): 423-431, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38407198

RESUMO

Surveillance for emerging pathogens is critical for developing early warning systems to guide preparedness efforts for future outbreaks of associated disease. To better define the epidemiology and burden of associated respiratory disease and acute flaccid myelitis (AFM), as well as to provide actionable data for public health interventions, we developed a multimodal surveillance program in Colorado, USA, for enterovirus D68 (EV-D68). Timely local, state, and national public health outreach was possible because prospective syndromic surveillance for AFM and asthma-like respiratory illness, prospective clinical laboratory surveillance for EV-D68 among children hospitalized with respiratory illness, and retrospective wastewater surveillance led to early detection of the 2022 outbreak of EV-D68 among Colorado children. The lessons learned from developing the individual layers of this multimodal surveillance program and how they complemented and informed the other layers of surveillance for EV-D68 and AFM could be applied to other emerging pathogens and their associated diseases.


Assuntos
Viroses do Sistema Nervoso Central , Enterovirus Humano D , Mielite , Doenças Neuromusculares , Doenças Respiratórias , Criança , Humanos , Colorado/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos , Águas Residuárias , Vigilância Epidemiológica Baseada em Águas Residuárias
5.
J Reprod Infant Psychol ; : 1-14, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591499

RESUMO

BACKGROUND: The 10-item Birth Satisfaction Scale-Revised (BSS-R) is a quick and easy survey instrument recommended by the International Consortium for Health Outcome Measures as the tool of choice for measuring women's birth satisfaction. AIM: To translate and validate a Vietnamese-language version of the BSS-R. METHOD: A quantitative cross-sectional method was used to gather data post translation and back-translation of a Vietnamese version of the BSS-R (VN-BSS-R). Data collected were psychometrically evaluated using key indices of validity and reliability. PARTICIPANTS: Vietnamese women who were within one month postpartum of birth (N = 383) took part in the study. RESULTS: Findings illustrate that a two-factor model offered excellent psychometric properties. With the two-factor VN-BSS-R, five items loaded onto a subscale 'Positive birth experiences' and the other five onto a second subscale 'Negative birth experiences'. This two-factor model offered a fit to data (root mean square error of approximation [RMSEA] = 0.07, 90% confidence interval [CI] [0.05, 0.09], root square mean residual [RMSE] = 0.04 and comparative fit index [CFI] = 0.97). Mean scores for the exploratory factor analysis [EFA]-derived 'positive' and 'negative' sub-scales were 17.12 (SD 2.34) and 8.40 (SD 4.18) respectively. CONCLUSION: The translated and validated VN-BSS-R is a psychometrically robust tool for measuring birth satisfaction in Vietnamese postpartum women.The VN-BSS-R is available for use to measure experiences and perceptions of intrapartum care received by Vietnamese women.

6.
Emerg Infect Dis ; 29(11): 2315-2324, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37877582

RESUMO

Enterovirus D68 (EV-D68) causes cyclical outbreaks of respiratory disease and acute flaccid myelitis. EV-D68 is primarily transmitted through the respiratory route, but the duration of shedding in the respiratory tract is unknown. We prospectively enrolled 9 hospitalized children with EV-D68 respiratory infection and 16 household contacts to determine EV-D68 RNA shedding dynamics in the upper respiratory tract through serial midturbinate specimen collections and daily symptom diaries. Five (31.3%) household contacts, including 3 adults, were EV-D68-positive. The median duration of EV-D68 RNA shedding in the upper respiratory tract was 12 (range 7-15) days from symptom onset. The most common symptoms were nasal congestion (100%), cough (92.9%), difficulty breathing (78.6%), and wheezing (57.1%). The median illness duration was 20 (range 11-24) days. Understanding the duration of RNA shedding can inform the expected rate and timing of EV-D68 detection in associated acute flaccid myelitis cases and help guide public health measures.


Assuntos
Enterovirus Humano D , Infecções por Enterovirus , Infecções Respiratórias , Criança , Adulto , Humanos , Enterovirus Humano D/genética , Colorado/epidemiologia , Sistema Respiratório , Infecções por Enterovirus/epidemiologia , Surtos de Doenças , RNA , Infecções Respiratórias/epidemiologia
7.
Appl Environ Microbiol ; 89(1): e0180722, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36602332

RESUMO

Metagenomics offers the possibility to screen for versatile biocatalysts. In this study, the microbial community of the Sorghum bicolor rhizosphere was spiked with technical cashew nut shell liquid, and after incubation, the environmental DNA (eDNA) was extracted and subsequently used to build a metagenomic library. We report the biochemical features and crystal structure of a novel esterase from the family IV, EH0, retrieved from an uncultured sphingomonad after a functional screen in tributyrin agar plates. EH0 (optimum temperature [Topt], 50°C; melting temperature [Tm], 55.7°C; optimum pH [pHopt], 9.5) was stable in the presence of 10 to 20% (vol/vol) organic solvents and exhibited hydrolytic activity against p-nitrophenyl esters from acetate to palmitate, preferably butyrate (496 U mg-1), and a large battery of 69 structurally different esters (up to 30.2 U mg-1), including bis(2-hydroxyethyl)-terephthalate (0.16 ± 0.06 U mg-1). This broad substrate specificity contrasts with the fact that EH0 showed a long and narrow catalytic tunnel, whose access appears to be hindered by a tight folding of its cap domain. We propose that this cap domain is a highly flexible structure whose opening is mediated by unique structural elements, one of which is the presence of two contiguous proline residues likely acting as possible hinges, which together allow for the entrance of the substrates. Therefore, this work provides a new role for the cap domain, which until now was thought to be an immobile element that contained hydrophobic patches involved in substrate prerecognition and in turn substrate specificity within family IV esterases. IMPORTANCE A better understanding of structure-function relationships of enzymes allows revelation of key structural motifs or elements. Here, we studied the structural basis of the substrate promiscuity of EH0, a family IV esterase, isolated from a sample of the Sorghum bicolor rhizosphere microbiome exposed to technical cashew nut shell liquid. The analysis of EH0 revealed the potential of the sorghum rhizosphere microbiome as a source of enzymes with interesting properties, such as pH and solvent tolerance and remarkably broad substrate promiscuity. Its structure resembled those of homologous proteins from mesophilic Parvibaculum and Erythrobacter spp. and hyperthermophilic Pyrobaculum and Sulfolobus spp. and had a very narrow, single-entry access tunnel to the active site, with access controlled by a capping domain that includes a number of nonconserved proline residues. These structural markers, distinct from those of other substrate-promiscuous esterases, can help in tuning substrate profiles beyond tunnel and active site engineering.


Assuntos
Microbiota , Sorghum , Esterases/metabolismo , Sorghum/metabolismo , Rizosfera , Ésteres/metabolismo , Especificidade por Substrato , Concentração de Íons de Hidrogênio
8.
J Intensive Care Med ; 38(12): 1151-1157, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37415515

RESUMO

OBJECTIVES: To investigate discordance in oxy-hemoglobin saturation measured both by pulse oximetry (SpO2) and arterial blood gas (ABG, SaO2) among critically ill coronavirus disease 2019 (COVID-19(+)) patients compared to COVID-19(-) patients. METHODS: Paired SpO2 and SaO2 readings were collected retrospectively from consecutive adult admissions to four critical care units in the United States between March and May 2020. The primary outcome was the rate of discordance (|SaO2-SpO2|>4%) in COVID-19(+) versus COVID-19(-) patients. The odds each cohort could have been incorrectly categorized as having a PaO2/FiO2 above or below 150 by their SpO2: Fractional inhaled oxygen ratio (pulse oximetry-derived oxyhemoglobin saturation:fraction of inspired oxygen ratio [SF]) was examined. A multivariate regression analysis assessed confounding by clinical differences between cohorts including pH, body temperature, renal replacement therapy at time of blood draw, and self-identified race. RESULTS: There were 263 patients (173 COVID-19(+)) included. The rate of saturation discordance between SaO2 and SpO2 in COVID-19(+) patients was higher than in COVID-19(-) patients (27.9% vs 16.7%, odds ratio [OR] 1.94, 95% confidence interval [CI]: 1.11 to 2.27). The average difference between SaO2 and SpO2 for COVID-19(+) patients was -1.24% (limits of agreement, -13.6 to 11.1) versus -0.11 [-10.3 to 10.1] for COVID-19(-) patients. COVID-19(+) patients had higher odds (OR: 2.61, 95% CI: 1.14-5.98) of having an SF that misclassified that patient as having a PaO2:FiO2 ratio above or below 150. There was not an association between discordance and the confounders of pH, body temperature, or renal replacement therapy at time of blood draw. After controlling for self-identified race, the association between COVID-19 status and discordance was lost. CONCLUSIONS: Pulse oximetry was discordant with ABG more often in critically ill COVID-19(+) than COVID-19(-) patients. However, these findings appear to be driven by racial differences between cohorts.


Assuntos
COVID-19 , Estado Terminal , Adulto , Humanos , Estudos Retrospectivos , Estado Terminal/terapia , Saturação de Oxigênio , Oximetria , Oxigênio , Hipóxia
9.
Environ Res ; 218: 114927, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36460071

RESUMO

This study aimed to develop an extremely highly porous activated carbon derived from soybean curd residues (SCB-AC) through two-step pyrolyzing coupled with KOH activating process and then apply it for removing paracetamol (PRC) and tetracycline (TCH) from water. The optimal conditions for chemical activation were 800 °C and the ratio of KOH to material (4/1; wt./wt.). SCB-AC adsorbents (before and after adsorption) were characterized by Brunauer-Emmet-Teller (BET) analyser, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy, and Raman spectroscopy. Adsorption kinetics, isotherm, and thermodynamics were concluded under batch experiments. The effects of pH (2-10) and NaCl (0-1 M) on adsorption processes were investigated. Reusable properties of laden SCB-AC were evaluated by studying desorption and cycles of adsorption/desorption. Results indicated that SCB-AC exhibited a large specific surface area (3306 m2/g) and high total pore volume (2.307 cm3/g), with mesoporous volume accounting for 86.9%. Its porosity characteristics (average pore width: 2.725 nm) are very appropriate for adsorbing two pharmaceuticals through pore-filling mechanism. Adsorption processes were less affected by the parameters: pH, NaCl, and water matrixes. The kinetics for adsorbing PRC reached a faster equilibrium than that for TCH. The Langmuir maximum adsorption capacity of SCB-AC (pHeq 7.0 and 25 °C) was 1235 mg/g (for adsorbing TCH) and 646 mg/g (PRC). Pore filling (confirmed by BET analyser) and π-π interaction (confirmed by FTIR and Raman spectroscopy) were dominant adsorption mechanisms. Those mechanisms were physisorption (ΔH° = 13.71 and -21.04 kJ/mol for adsorbing TCH and PRC, respectively). SCB-AC can serve as an outstanding material for removing pharmaceuticals from water.


Assuntos
Acetaminofen , Poluentes Químicos da Água , Adsorção , Cloreto de Sódio , Poluentes Químicos da Água/análise , Tetraciclina , Antibacterianos , Termodinâmica , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Preparações Farmacêuticas , Concentração de Íons de Hidrogênio
10.
Tetrahedron Lett ; 1182023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38505129

RESUMO

Catalytic alkene hydrogenation is a powerful method that has been widely used in the syntheses of valuable products ranging from commodity chemicals to pharmaceuticals. Hydrogenation has also been a key strategy for selectively introducing heavy hydrogen isotopes to small molecules, a key strategy for metabolism studies and even the synthesis of "heavy drugs," where the hydrogen isotope is a key element of the active pharmaceutical ingredient. Traditional hydrogenations with pressurized H2 gas are atom economic but often require complex reaction setups or expensive metal catalysts. Further, use of diatomic hydrogen necessarily limits the ability to incorporate different hydrogen isotopes at each alkene position, with H2, D2, and T2 each resulting in compete labeling of the alkene. In response to these challenges, a recent and growing movement has sought to develop transfer hydrogenation methods using non-H2 hydrogen sources and earth abundant element catalysts to simplify reaction operation. Excitingly, recent developments have delivered transfer hydrogenations that proceed using cooperative hydrogen donor reagents, permitting the controllable incorporation of different hydrogen isotopes at each position of the alkene via reagent control. In this Digest, we disclose recent advances in Earth-abundant metal-catalyzed cooperative transfer hydrogenation of alkenes with various combinations of two distinct transfer hydrogen reagents as non-H2 hydrogen sources.

11.
Proc Natl Acad Sci U S A ; 117(11): 5733-5740, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123103

RESUMO

The field of chemical modification of proteins has been dominated by random modification of lysines or more site-specific labeling of cysteines, each with attendant challenges. Recently, we have developed oxaziridine chemistry for highly selective modification of methionine called redox-activated chemical tagging (ReACT) but have not broadly tested the molecular parameters for efficient and stable protein modification. Here we systematically scanned methionines throughout one of the most popular antibody scaffolds, trastuzumab, used for antibody engineering and drug conjugation. We tested the expression, reactivities, and stabilities of 123 single engineered methionines distributed over the surface of the antibody when reacted with oxaziridine. We found uniformly high expression for these mutants and excellent reaction efficiencies with a panel of oxaziridines. Remarkably, the stability to hydrolysis of the sulfimide varied more than 10-fold depending on temperature and the site of the engineered methionine. Interestingly, the most stable and reactive sites were those that were partially buried, presumably because of their reduced access to water. There was also a 10-fold variation in stability depending on the nature of the oxaziridine, which was determined to be inversely correlated with the electrophilic nature of the sulfimide. Importantly, the stabilities of the best analogs were sufficient to support their use as antibody drug conjugates and potent in a breast cancer mouse xenograft model over a month. These studies provide key parameters for broad application of ReACT for efficient, stable, and site-specific antibody and protein bioconjugation to native or engineered methionines.


Assuntos
Aziridinas/análise , Imunoconjugados/química , Metionina/análise , Animais , Antineoplásicos/normas , Linhagem Celular Tumoral , Estabilidade de Medicamentos , Feminino , Humanos , Imunoconjugados/genética , Imunoconjugados/imunologia , Camundongos , Camundongos Nus , Engenharia de Proteínas/métodos , Estabilidade Proteica
12.
J Med Internet Res ; 25: e46216, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37261889

RESUMO

BACKGROUND: The growing public interest and awareness regarding the significance of sleep is driving the demand for sleep monitoring at home. In addition to various commercially available wearable and nearable devices, sound-based sleep staging via deep learning is emerging as a decent alternative for their convenience and potential accuracy. However, sound-based sleep staging has only been studied using in-laboratory sound data. In real-world sleep environments (homes), there is abundant background noise, in contrast to quiet, controlled environments such as laboratories. The use of sound-based sleep staging at homes has not been investigated while it is essential for practical use on a daily basis. Challenges are the lack of and the expected huge expense of acquiring a sufficient size of home data annotated with sleep stages to train a large-scale neural network. OBJECTIVE: This study aims to develop and validate a deep learning method to perform sound-based sleep staging using audio recordings achieved from various uncontrolled home environments. METHODS: To overcome the limitation of lacking home data with known sleep stages, we adopted advanced training techniques and combined home data with hospital data. The training of the model consisted of 3 components: (1) the original supervised learning using 812 pairs of hospital polysomnography (PSG) and audio recordings, and the 2 newly adopted components; (2) transfer learning from hospital to home sounds by adding 829 smartphone audio recordings at home; and (3) consistency training using augmented hospital sound data. Augmented data were created by adding 8255 home noise data to hospital audio recordings. Besides, an independent test set was built by collecting 45 pairs of overnight PSG and smartphone audio recording at homes to examine the performance of the trained model. RESULTS: The accuracy of the model was 76.2% (63.4% for wake, 64.9% for rapid-eye movement [REM], and 83.6% for non-REM) for our test set. The macro F1-score and mean per-class sensitivity were 0.714 and 0.706, respectively. The performance was robust across demographic groups such as age, gender, BMI, or sleep apnea severity (accuracy 73.4%-79.4%). In the ablation study, we evaluated the contribution of each component. While the supervised learning alone achieved accuracy of 69.2% on home sound data, adding consistency training to the supervised learning helped increase the accuracy to a larger degree (+4.3%) than adding transfer learning (+0.1%). The best performance was shown when both transfer learning and consistency training were adopted (+7.0%). CONCLUSIONS: This study shows that sound-based sleep staging is feasible for home use. By adopting 2 advanced techniques (transfer learning and consistency training) the deep learning model robustly predicts sleep stages using sounds recorded at various uncontrolled home environments, without using any special equipment but smartphones only.


Assuntos
Aprendizado Profundo , Smartphone , Humanos , Gravação de Som , Ambiente Domiciliar , Fases do Sono , Sono
13.
Sensors (Basel) ; 23(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36772668

RESUMO

In this study, the short-term creep effect (STCE) on strain transfer from fiber-reinforced polymer (FRP) strips to fiber Bragg grating-optical fiber (FBG-OF) sensors was investigated. Thirty OF sensors attached to FRP strips were investigated through three primary test parameters: bond length (40, 60, 80, 100, 120, and 150 mm); adhesive type (epoxy resin, CN adhesive, and epoxy resin combined with CN adhesive); and bonding method (embedded and external bonding methods). The strain transfer ability of the OF sensors was evaluated based on the strain ratio of the OF sensor to the FRP strip under different sustained stresses of 20, 40, 50, and 60% of the FRP ultimate tensile strength (fu). From the test results, it was found that the debonding phenomenon occurred at the interface between the FBG-OF sensor and the adhesive and was clearly observed after applying a load for three days. It was also found that the CN adhesive showed better strain transfer compared to the other adhesive types. Regarding the OF sensors bonded by epoxy resin, in order to maintain strain transfer ability under a high level of sustained stress (0.6fu), minimum bond lengths of 100 and 120 mm were required for the embedded and external bonding methods, respectively.

14.
J Environ Manage ; 325(Pt A): 116475, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36272293

RESUMO

Two flaws in concepts were identified and discussed in the paper ("Removal of Pb(II) from contaminated waters using cellulose sulfate/chitosan aerogel: Equilibrium, kinetics, and thermodynamic studies". J. Environ. Manag. 286, 112167; https://doi.org/10.1016/j.jenvman.2021.112167). In the literature, the Radke-Prausnitz model is expressed in different forms, but some of them are incorrect. The first flaw is related to the nonlinear form of the Radke-Prausnitz model. The nonlinear form of this three parameters model is expressed correctly as [Formula: see text] . The units of two parameters are ARP (L/kg) and BRP [(mol/kg)/(mol/L)ß] by considering qe (mol/kg) and Ce (mol/L). The limitation for its exponent is 0≤ ß ≤ 1. This model is developed by two authors (Radke and Prausnitz). The correct paper (DOI: 10.1021/i160044a003) cited as reference of this model is "Radke, C.J., Prausnitz, J.M., 1972. Adsorption of organic solutes from dilute aqueous solution of activated carbon. Ind. Eng. Chem. 11, 445-451". The second is the misconception about the unit of the Langmuir constant (KL; L/mg). The correct unit of KL is litre per milligram of adsorbate (i.e., Pb ions), not litre per milligram of adsorbent (the cellulose sulfate/chitosan aerogel material as reported by Najaflou and co-workers. They proposed a new equation [KL (L/mg) × m/V (mg/L)] to convert the Langmuir constant and then applied it to calculate the thermodynamic parameters of the adsorption process. The m/V is a solid/liquid ratio (g/L or kg/L). However, this conversion and application are mistakes that were thoroughly discussed in this paper. The correction is KEqo=1γAdsorbate×KLLmol×ComolL, with C° (1 mol/L by definition) being the standard state of solute and γAdsorbate (dimensionless) being the activity coefficient of adsorbate in solution. To avoid unexpected mistakes, the present authors suggest that researchers should have a correct citation (citing the original reference instead of using secondary references) and check the consistency of units (i.e., the constants of adsorption models) carefully.


Assuntos
Quitosana , Poluentes Químicos da Água , Humanos , Adsorção , Dinâmica não Linear , Chumbo , Concentração de Íons de Hidrogênio , Cinética , Soluções , Termodinâmica
15.
Br J Cancer ; 127(3): 569-576, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35440668

RESUMO

INTRODUCTION: Small cell lung cancer (SCLC) is an aggressive malignancy with no established biomarkers. Schlafen 11(SLFN11), a DNA/RNA helicase that sensitises cancer cells to DNA-damaging agents, has emerged as a promising predictive biomarker for several drug classes including platinum and PARP inhibitors. Detection of SLFN11 in circulating tumour cells (CTCs) may provide a valuable alternative to tissue sampling. METHODS: SLFN11 expression was evaluated in tumour samples and characterised in circulating tumour cells (CTC) longitudinally to determine its potential role as a biomarker of response. RESULTS: Among 196 SCLC tumours, 51% expressed SLFN11 by IHC. In addition, 20/29 extra-thoracic high-grade neuroendocrine tumours expressed SLFN11 expression. In 64 blood samples from 42 SCLC patients, 83% (53/64) of samples had detectable CTCs, and SLFN11-positive CTCs were detected in 55% (29/53). Patients actively receiving platinum treatment had the lowest number of CTCs and a lower percentage of SLFN11-positive CTCs (p = 0.014). Analysis from patients with longitudinal samples suggest a decrease in CTC number and in SLFN11 expression that correlates with clinical response. CONCLUSIONS: SLFN11 levels can be monitored in CTCs from SCLC patients using non-invasive liquid biopsies. The ability to detect SLFN11 in CTCs from SCLC patients adds a valuable tool for the detection and longitudinal monitoring of this promising biomarker.


Assuntos
Neoplasias Pulmonares , Células Neoplásicas Circulantes , Proteínas Nucleares , Carcinoma de Pequenas Células do Pulmão , Biomarcadores , Biomarcadores Tumorais , Linhagem Celular Tumoral , DNA/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Células Neoplásicas Circulantes/patologia , Proteínas Nucleares/genética , Platina/uso terapêutico , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológico
16.
Oncologist ; 27(12): 1004-e926, 2022 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-36124629

RESUMO

BACKGROUND: PI3K/mTOR inhibition leads to apoptosis of NOTCH1-mutant head and neck squamous cell carcinoma (HNSCC) cells. We tested the efficacy of the PI3K/mTOR inhibitor bimiralisib in patients with NOTCH1-mutant HNSCC. METHODS: Patients with recurrent/metastatic NOTCH1-mutant HNSCC who had progressed during chemotherapy and immunotherapy received bimiralisib until unacceptable toxicity or progression. To assess whether NOTCH1 mutations can be detected in blood, we measured circulating tumor DNA (ctDNA). To assess activated NOTCH1 protein levels, we quantitated cleaved NOTCH1 (cl-NOTCH) by immunohistochemistry. RESULTS: Eight patients were treated, and 6 were evaluable for response. The objective response rate was 17%. For all 8 patients, median progression-free and overall survival was 5 and 7 months, respectively. Bimiralisib was well tolerated, with expected hyperglycemia. Pharmacokinetic values were consistent with published studies. NOTCH1 mutations were detected in 83.3% of ctDNA. Staining for tumor cl-NOTCH1 was negative. The trial closed early due to sponsor insolvency. CONCLUSION: Although the trial was small, outcomes with bimiralisib were better than the historical standard of care; Results will need to be confirmed in a larger trial. The lack of cl-NOTCH1 was consistent with loss-of-function mutations and validated our mutation function algorithm. The ability to detect NOTCH1 mutations in blood will help future studies. (ClinicalTrials.gov Identifier: NCT03740100).


Assuntos
Neoplasias de Cabeça e Pescoço , Fosfatidilinositol 3-Quinase , Humanos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Fosfatidilinositóis , Receptor Notch1/genética
17.
Clin Exp Immunol ; 207(3): 351-359, 2022 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-35553638

RESUMO

We previously showed increased steroid-resistant CD28null CD8+ senescent lymphocyte subsets in the peripheral blood from patients with chronic obstructive pulmonary disease (COPD). These cells expressed decreased levels of the glucocorticoid receptor (GCR), suggesting their contribution to the steroid-resistant property of these cells. COPD is a disease of the small airways (SA). We, therefore, hypothesized that there would be a further increase in these steroid-resistant lymphocytes in the lung, particularly in the SA. We further hypothesized that the pro-inflammatory/cytotoxic potential of these cells could be negated using prednisolone with low-dose cyclosporin A. Blood, bronchoalveolar lavage, large proximal, and small distal airway brushings were collected from 11 patients with COPD and 10 healthy aged-matched controls. The cytotoxic mediator granzyme b, pro-inflammatory cytokines IFNγ/TNFα, and GCR were determined in lymphocytes subsets before and after their exposure to 1µM prednisolone and/or 2.5 ng/mL cyclosporin A. Particularly in the SA, COPD subjects showed an increased percentage of CD28null CD8 T-cells and NKT-like cells, with increased expression of granzyme b, IFNγ and TNFα and a loss of GCR, compared with controls. Significant negative correlations between SA GCR expression and IFNγ/TNFα production by T and NKT-like cells (eg, T-cell IFNγ R = -0.834, P = 0.031) and with FEV1 (R = -0.890) were shown. Cyclosporine A and prednisolone synergistically increased GCR expression and inhibited pro-inflammatory cytokine production by CD28null CD8- T and NKT-like cells. COPD is associated with increased pro-inflammatory CD28null CD8+ T and NKT-like cells in the SA. Treatments that increase GCR in these lymphocyte subsets may improve the efficacy of clinical treatment.


Assuntos
Antígenos CD28 , Doença Pulmonar Obstrutiva Crônica , Idoso , Antígenos CD28/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Ciclosporina/farmacologia , Ciclosporina/uso terapêutico , Granzimas/metabolismo , Humanos , Prednisolona/farmacologia , Prednisolona/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo
18.
Histochem Cell Biol ; 158(5): 485-496, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35849202

RESUMO

Zinc homeostasis is vital to immune and other organ system functions, yet over a quarter of the world's population is zinc deficient. Abnormal zinc transport or storage protein expression has been linked to diseases, such as cancer and chronic obstructive pulmonary disorder. Although recent studies indicate a role for zinc regulation in vascular functions and diseases, detailed knowledge of the mechanisms involved remains unknown. This study aimed to assess protein expression and localization of zinc transporters of the SLC39A/ZIP family (ZIPs) and metallothioneins (MTs) in human subcutaneous microvessels and to relate them to morphological features and expression of function-related molecules in the microvasculature. Microvessels in paraffin biopsies of subcutaneous adipose tissues from 14 patients undergoing hernia reconstruction surgery were analysed for 9 ZIPs and 3 MT proteins by MQCM (multifluorescence quantitative confocal microscopy). Zinc regulation proteins detected in human microvasculature included ZIP1, ZIP2, ZIP8, ZIP10, ZIP12, ZIP14 and MT1-3, which showed differential localization among endothelial and smooth muscle cells. ZIP1, ZIP2, ZIP12 and MT3 showed significantly (p < 0.05) increased immunoreactivities, in association with increased microvascular muscularization, and upregulated ET-1, α-SMA and the active form of p38 MAPK (Thr180/Tyr182 phosphorylated, p38 MAPK-P). These findings support roles of the zinc regulation system in microvascular physiology and diseases.


Assuntos
Proteínas de Transporte de Cátions , Humanos , Proteínas de Transporte de Cátions/metabolismo , Zinco/metabolismo , Metalotioneína/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
19.
Neuromodulation ; 25(7): 970-979, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34096146

RESUMO

OBJECTIVES: Dorsal root ganglion (DRG) stimulation is effective in treating chronic pain. While burst stimulation has been proven to enhance the therapeutic efficacy in spinal cord stimulation, currently only a tonic stimulation waveform is clinically used in DRG stimulation. We hypothesized that burst DRG stimulation might also produce analgesic effect in a preclinical neuropathic pain model. We evaluated both the therapeutic effects of burst DRG stimulation and the possible effects of DRG stimulation upon inflammation within the DRG in a preclinical neuropathic pain model. MATERIALS AND METHODS: Rats received either a painful tibial nerve injury or sham surgery. Analgesic effects of DRG stimulation were evaluated by testing a battery of evoked pain-related behaviors as well as measuring the positive affective state associated with relief of spontaneous pain using conditioned place preference. Histological evidence for neuronal trauma or neuroinflammation was evaluated. RESULTS: All of the waveforms tested (20 Hz-tonic, 20 Hz-burst, and 40 Hz-burst) have similar analgesic effects in sensory tests and conditioned place preference. Long-term DRG stimulation for two weeks does not change DRG expression of markers for nerve injury and neuroinflammation. CONCLUSIONS: DRG stimulation using burst waveform might be also suitable for treating neuropathic pain.


Assuntos
Neuralgia , Traumatismos dos Nervos Periféricos , Analgésicos , Animais , Gânglios Espinais/fisiologia , Neuralgia/metabolismo , Neuralgia/terapia , Traumatismos dos Nervos Periféricos/metabolismo , Ratos , Ratos Sprague-Dawley , Nervo Tibial
20.
Korean J Chem Eng ; : 1-10, 2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35095157

RESUMO

This study developed a new α-Fe2O3 (hematite) nanoparticles-loaded spherical biochar (H-SB) through the direct pyrolysis of glucose-derived spherical hydrochar and FeCl3. The optimal impregnation ratio (hydrochar and FeCl3) was 1/1.25 (wt/wt). H-SB was applied to remove paracetamol (PRC) from water. Results indicated that H-SB exhibited a relatively low surface area (127 m2/g) and total pore volume (0.089 cm3/g). The presence of iron particles in its surface was confirmed by scanning electron microscopy with energy dispersive spectroscopy. The dominant form of iron nanoparticles (α-Fe2O3) in its surface was confirmed by X-ray powder diffraction and Raman spectrum. The crystallite size of α-Fe2O3 in H-SB was 27.4 nm. The saturation magnetization of H-SB was 6.729 cmu/g. The analysis of Fourier-transform infrared spectroscopy demonstrated that the C-O and O-H groups were mainly responsible for loading α-Fe2O3 nanoparticles in its surface. The adsorption study indicated the amount of PRC adsorbed by H-SB slightly decreased within solution pH from 2 to 11. The adsorption reached a fast saturation after 120 min. The Langmuir maximum adsorption capacity of H-SB was 49.9 mg/g at 25 °C and pH 7.0. Ion-dipole interaction and π-π interaction played an important role in adsorption mechanisms, while hydrogen bonding and pore filling were minor. Therefore, H-SB can serve as a promising material for treating PRC-contaminated water streams. ELECTRONIC SUPPLEMENTARY MATERIAL: Supplementary material is available in the online version of this article at 10.1007/s11814-021-1013-z.

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