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1.
Plant Cell ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38701340

RESUMO

Improving photosynthesis, the fundamental process by which plants convert light energy into chemical energy, is a key area of research with great potential for enhancing sustainable agricultural productivity and addressing global food security challenges. This perspective delves into the latest advancements and approaches aimed at optimizing photosynthetic efficiency. Our discussion encompasses the entire process, beginning with light harvesting and its regulation and progressing through the bottleneck of electron transfer. We then delve into the carbon reactions of photosynthesis, focusing on strategies targeting the enzymes of the Calvin-Benson-Bassham (CBB) cycle. Additionally, we explore methods to increase CO2 concentration near the Rubisco, the enzyme responsible for the first step of CBB cycle, drawing inspiration from various photosynthetic organisms, and conclude this section by examining ways to enhance CO2 delivery into leaves. Moving beyond individual processes, we discuss two approaches to identifying key targets for photosynthesis improvement: systems modeling and the study of natural variation. Finally, we revisit some of the strategies mentioned above to provide a holistic view of the improvements, analyzing their impact on nitrogen use efficiency and on canopy photosynthesis.

2.
Ann R Coll Surg Engl ; 106(4): 377-384, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37843132

RESUMO

INTRODUCTION: Inhalation of foreign bodies represents a potentially fatal emergency in both adults and children. Chest x-ray, in isolation, is neither sensitive nor specific. Rigid bronchoscopy represents the gold standard to diagnose and retrieve paediatric foreign bodies. Cases are encountered infrequently, creating anxieties about their management. Little is known about the confidence in, and maintenance of, rigid bronchoscopy skills by ear, nose and throat teams. METHODS: A 15-question survey was completed by 50 practising otolaryngology consultants in England. RESULTS: Results show that almost 40% of otolaryngology consultants covering rigid bronchoscopy have not performed bronchoscopy in more than 5 years. Consultants raised concerns about the anaesthetic support and the speed of equipment assembly. Questions on clinical practice showed disparities in practice in the same scenario. CONCLUSIONS: The authors advocate addressing many of the issues raised by the study with a greater availability of simulation courses and regular scheduled intradepartmental teaching days for all professionals involved. National guidelines on criteria for transfer to tertiary centres would improve the consistency of practice.


Assuntos
Corpos Estranhos , Otolaringologia , Criança , Humanos , Lactente , Broncoscopia/métodos , Consultores , Inquéritos e Questionários , Corpos Estranhos/diagnóstico , Estudos Retrospectivos
3.
Sci Rep ; 13(1): 20989, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-38017027

RESUMO

In Alligator mississippiensis the spinal dura is surrounded by a venous sinus; pressure waves can propagate in the spinal venous blood, and these spinal venous pressures can be transmitted to the spinal cerebrospinal fluid (CSF). This study was designed to explore pressure transfer between the spinal venous blood and the spinal CSF. At rest the cardiac-related CSF pulsations are attenuated and delayed, while the ventilatory-related pulsations are amplified as they move from the spinal venous blood to the spinal CSF. Orthostatic gradients resulted in significant alterations of both cardiac- and ventilatory-related CSF pulsations. Manual lateral oscillations of the alligator's tail created pressure waves in the spinal CSF that propagated, with slight attenuation but no delay, to the cranial CSF. Oscillatory pressure pulsations in the spinal CSF and venous blood had little influence on the underlying ventilatory pulsations, though the same oscillatory pulsations reduced the ventilatory- and increased the cardiac-related pulsations in the cranial CSF. In Alligator the spinal venous anatomy creates a more complex pressure relationship between the venous and CSF systems than has been described in humans.


Assuntos
Pressão do Líquido Cefalorraquidiano , Dura-Máter , Humanos , Pressão Venosa , Líquido Cefalorraquidiano/fisiologia , Pressão Sanguínea/fisiologia
4.
Plant Physiol ; 193(2): 966-979, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37265110

RESUMO

There is a limited understanding of the carbon assimilation capacity of nonfoliar green tissues and its impact on yield and seed quality since most photosynthesis research focuses on leaf photosynthesis. In this study, we investigate the photosynthetic efficiency of soybean (Glycine max) pods and seeds in a field setting and evaluate its effect on mature seed weight and composition. We demonstrate that soybean pod and seed photosynthesis contributes 13% to 14% of the mature seed weight. Carbon assimilation by soybean pod and seed photosynthesis can compensate for 81% of carbon loss through the respiration of the same tissues, and our model predicts that soybean pod and seed photosynthesis contributes up to 9% of the total daily carbon gain of the canopy. Chlorophyll fluorescence (CF) shows that the operating efficiency of photosystem II in immature soybean seeds peaks at the 10 to 100 mg seed weight stage, while that of immature pods peaks at the 75 to 100 mg stage. This study provides quantitative information about the efficiency of soybean pod and seed photosynthesis during tissue development and its impact on yield.


Assuntos
Carbono , Glycine max , Fotossíntese , Folhas de Planta , Sementes
5.
Sci Rep ; 13(1): 2868, 2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36806155

RESUMO

To assess if SARS-CoV-2 (COVID-19) systemic disease can be determined by available nucleoprotein assays, we compared the performance of three commercial SARS-CoV-2 nucleoprotein (N) assays in plasma. A total of 272 plasma samples collected in the period November-December 2021 were analyzed by the methods Simoa SARS CoV-2 N Protein Advantage Kit [Quanterix Simoa], Solsten SARS-CoV-2 Antigen enzyme immunosorbent assay (ELISA) [Solsten ELISA], and Elecsys SARS-CoV-2 Antigen electrochemiluminescence immunoassay [Elecsys ECLIA]. Additionally, a dilution series of inactivated virus culture was analyzed by the three assays. The SARS CoV-2 PCR-status was not known for the patients. Linear correlation in the pairwise correlation between assays as well as linearity of dilution series of inactivated virus culture was estimated by Spearman score. Sensitivity and specificity were estimated by pairwise comparison. The three assays showed poor agreement on patient samples with regards to concentration. Performance on virus culture was excellent but with different level of detection (LOD). Positive vs negative results show comparable sensitivity and specificity of Quanterix Simoa and Solsten ELISA, with a higher LOD in Elecsys ECLIA and thus lower sensitivity and high specificity. N by all tested assays can be used as a marker for systemic COVID-19 disease.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , Plasma , Bioensaio , Imunoadsorventes , Nucleoproteínas
6.
J Public Health (Oxf) ; 45(2): e275-e284, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35285902

RESUMO

BACKGROUND: The Early CDT®-Lung antibody blood test plus serial computed tomography scans for test-positives (TPGs) reduces late-stage lung cancer presentation. This study assessed the psychological outcomes of this approach. METHODS: Randomized controlled trial (n = 12 208) comparing psychological outcomes 1-12 months post-recruitment in a subsample (n = 1032) of TPG, test-negative (TNG) and control groups (CG). RESULTS: Compared to TNG, TPG had lower positive affect (difference between means (DBM), 3 months (3m: -1.49 (-2.65, - 0.33)), greater impact of worries (DBM 1m: 0.26 (0.05, 0.47); 3m: 0.28 (0.07, 0.50)), screening distress (DBM 1m: 3.59 (2.28, 4.90); 3m: 2.29 (0.97, 3.61); 6m: 1.94 (0.61, 3.27)), worry about tests (odds ratio (OR) 1m: 5.79 (2.66, 12.63) and more frequent lung cancer worry (OR 1m: 2.52 (1.31, 4.83); 3m: 2.43 (1.26, 4.68); 6m: 2.87 (1.48, 5.60)). Compared to CG, TPG had greater worry about tests (OR 1m: 3.40 (1.69, 6.84)). TNG had lower negative affect (log-transformed DBM 3m: -0.08 (-0.13, -0.02)), higher positive affect (DBM 1m: 1.52 (0.43, 2.61); 3m: 1.43 (0.33, 2.53); 6m: 1.27 (0.17, 2.37)), less impact of worries (DBM 3m: -0.27 (-0.48, -0.07)) and less-frequent lung cancer worry (OR 3m: 0.49 (0.26, 0.92)). CONCLUSIONS: Negative psychological effects in TPG and positive effects in TNG were short-lived and most differences were small.


Assuntos
Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Testes Hematológicos
7.
Clin Chim Acta ; 537: 87-95, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36279940

RESUMO

BACKGROUND: The objective of our study was to evaluate a single blood collection tube with a novel antithrombotic formulation to measure both hematological, biochemical, and d-dimer analytes. METHODS: Paired samples of gold standard blood tubes (EDTA, lithium heparin, sodium citrate) and a new antithrombotic formulation blood tube were collected from 187 patients. The new antithrombotic tube is a lithium heparin tube preloaded with a liquid form of prostacyclin analog. The novel tube was tested on seventeen hematological parameters and smears against EDTA, on fourteen biochemical parameters against lithium heparin and on d-dimer against sodium citrate. RESULTS: All correlation coefficients were close to 0.99. The Bland-Altman analyses presented a satisfactory correspondence for all analytes. All the hematological examinations demonstrated comparable results between EDTA and the novel formulation, except for platelet counts analyzed by impedance method, but not by fluorescence. We detected lower mean platelet volume with/without outliers (5.06%)/(5.13%) in the novel formulation and increased mean corpuscular hemoglobin concentration (2.55%). All the biochemistry analytes demonstrated comparable results between lithium heparin and the novel tube. d-dimer showed comparable results between citrated blood and the novel formulation after dilution correction. CONCLUSIONS: We describe a novel antithrombotic formulation tube with the potential to be introduced into clinical laboratories for simultaneous analysis of thirty-two blood analytes.


Assuntos
Heparina , Iloprosta , Humanos , Fibrinolíticos , Lítio , Ácido Edético , Coleta de Amostras Sanguíneas/métodos , Citrato de Sódio
8.
J Appl Lab Med ; 7(3): 711-726, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35134936

RESUMO

BACKGROUND: Throughout the coronavirus disease 2019 (Covid-19) pandemic numerous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody assays have been approved through Emergency Use Authorization and require further evaluation of sensitivity and specificity in clinical laboratory settings prior to implementation. METHODS: We included 1733 samples from 375 PCR-confirmed SARS-CoV-2-positive individuals of the North Zealand Covid-19 Cohort in an 8-month period. We investigated diagnostic sensitivity and specificity against consensus and PCR and interassay agreement over time for 5 SARS-CoV-2 immunoassays [Roche-nucleocapsid (NC)-total, Roche-receptor binding domain (RBD)-total, Siemens-RBD-IgG, Siemens-RBD-total, Thermo Fisher Scientific (TFS)-RBD-IgG] commercially available on automated platforms and 2 ELISA assays (TFS-RBD-total, Wantai-RBD-total). RESULTS: Early interassay discrepancy in up to 49% of samples decreased steadily during the first 18 days. By day 18, all assays had reached a plateau between 82.3% and 90.5% seropositivity compared to PCR. Assays ranked by closest agreement with the consensus model beyond day 18 (sensitivity/specificity against consensus) were as follows: Roche-RBD-total, 99.8%/100.0%; Wantai-RBD-total, 99.8%/99.7%; Roche-NC-total, 97.8%/100.0%; Siemens-RBD-total, 98.0%/98.7%; TFS-RBD-total, 96.9%/99.7%; TFS-RBD-IgG, 91.5%/100.0%; and Siemens-RBD-IgG, 94.6%/89.9%. We found that 7.8% of PCR-positive patients remained seronegative in all assays throughout the study. CONCLUSIONS: All included assays had sensitivities against consensus >90% past day 18. For the current recommended use of antibody assays to detect former, undocumented Covid-19, our data suggest the use of total antibody assays rather than IgG-specific assays due to higher long-term sensitivity. Finally, a nonresponding subpopulation of 7.8% in our cohort with persistent seronegative results raises concern of a possible substantial number of people with continued low protection following natural SARS-CoV-2 infection.


Assuntos
COVID-19 , Anticorpos Antivirais , COVID-19/diagnóstico , Teste Sorológico para COVID-19 , Humanos , Imunoglobulina G , SARS-CoV-2
9.
J Laryngol Otol ; 136(8): 755-759, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35000642

RESUMO

OBJECTIVES: To quantify patient eligibility for cochlear implantation following National Institute for Health and Care Excellence 2019 guidelines (TA566) over five years at our institution, and identify factors influencing patients' decisions surrounding cochlear implantation referral. METHODS: A multi-perspective service evaluation was conducted at a district general hospital, comprising cochlear implantation eligible patients. The main outcome measures were: eligibility numbers for 2014-2019, comparing application of TA566 versus 2009 (TA166) guidelines; and patient interview transcripts and questionnaires. RESULTS: There was a 259 per cent average increase in cochlear implantation eligibility from 2014 to 2019. Most patients' thresholds were 80 dB HL or more at 3 kHz and 4 kHz. There are several cochlear implantation barriers, including patient-centred issues (e.g. health-related anxieties, implantation misperceptions) and external barriers (difficulty getting to regional implant centres). Motivating factors for cochlear implantation include improved quality of life and access to local cochlear implantation services. CONCLUSION: The TA566 guidelines have increased cochlear implantation eligibility, putting pressure on cochlear implantation centres and referring hospitals. Current referral systems have external and patient-centred implantation barriers. British cochlear implantation delivery may need rethinking to meet increasing populational demands and improve accessibility for those most vulnerable to these barriers.


Assuntos
Implante Coclear , Implantes Cocleares , Auxiliares de Audição , Percepção da Fala , Adulto , Hospitais Gerais , Humanos , Qualidade de Vida , Encaminhamento e Consulta
10.
Microbiome ; 9(1): 112, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039416

RESUMO

BACKGROUND: The public transit is a built environment with high occupant density across the globe, and identifying factors shaping public transit air microbiomes will help design strategies to minimize the transmission of pathogens. However, the majority of microbiome works dedicated to the public transit air are limited to amplicon sequencing, and our knowledge regarding the functional potentials and the repertoire of resistance genes (i.e. resistome) is limited. Furthermore, current air microbiome investigations on public transit systems are focused on single cities, and a multi-city assessment of the public transit air microbiome will allow a greater understanding of whether and how broad environmental, building, and anthropogenic factors shape the public transit air microbiome in an international scale. Therefore, in this study, the public transit air microbiomes and resistomes of six cities across three continents (Denver, Hong Kong, London, New York City, Oslo, Stockholm) were characterized. RESULTS: City was the sole factor associated with public transit air microbiome differences, with diverse taxa identified as drivers for geography-associated functional potentials, concomitant with geographical differences in species- and strain-level inferred growth profiles. Related bacterial strains differed among cities in genes encoding resistance, transposase, and other functions. Sourcetracking estimated that human skin, soil, and wastewater were major presumptive resistome sources of public transit air, and adjacent public transit surfaces may also be considered presumptive sources. Large proportions of detected resistance genes were co-located with mobile genetic elements including plasmids. Biosynthetic gene clusters and city-unique coding sequences were found in the metagenome-assembled genomes. CONCLUSIONS: Overall, geographical specificity transcends multiple aspects of the public transit air microbiome, and future efforts on a global scale are warranted to increase our understanding of factors shaping the microbiome of this unique built environment.


Assuntos
Microbiota , Bactérias/genética , Geografia , Hong Kong , Humanos , Metagenoma/genética , Microbiota/genética
11.
Anaesthesia ; 76(6): 818-831, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32981051

RESUMO

The aim of this systematic review and meta-analysis was to examine the efficacy, time taken and the safety of neuraxial blockade performed for obstetric patients with the assistance of preprocedural ultrasound, in comparison with the landmark palpation method. The bibliographic databases Central, CINAHL, EMBASE, Global Health, MEDLINE, Scopus and Web of Science were searched from inception to 13 February 2020 for randomised controlled trials that included pregnant women having neuraxial procedures with preprocedural ultrasound as the intervention and conventional landmark palpation as the comparator. For continuous and dichotomous outcomes, respectively, we calculated the mean difference using the inverse-variance method and the risk ratio with the Mantel-Haenszel method. In all, 22 trials with 2462 patients were included. Confirmed by trial sequential analysis, preprocedural ultrasound increased the first-pass success rate by a risk ratio (95%CI) of 1.46 (1.16-1.82), p = 0.001 in 13 trials with 1253 patients. No evidence of a difference was found in the total time taken between preprocedural ultrasound and landmark palpation, with a mean difference (95%CI) of 50.1 (-13.7 to 113.94) s, p = 0.12 in eight trials with 709 patients. The quality of evidence was graded as low and very low, respectively, for these co-primary outcomes. Sub-group analysis underlined the increased benefit of preprocedural ultrasound for those in whom the neuraxial procedure was predicted to be difficult. Complications, including postpartum back pain and headache, were decreased with preprocedural ultrasound. The adoption of preprocedural ultrasound for neuraxial procedures in obstetrics is recommended and, in the opinion of the authors, should be considered as a standard of care, in view of its potential to increase efficacy and reduce complications without significant prolongation of the total time required.


Assuntos
Analgesia Epidural/métodos , Analgesia Obstétrica/métodos , Anestesia Epidural/métodos , Anestesia Obstétrica/métodos , Palpação/métodos , Ultrassonografia/métodos , Espaço Epidural/anatomia & histologia , Feminino , Humanos , Gravidez
12.
Epidemiol Infect ; 148: e299, 2020 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-33261680

RESUMO

Influenza vaccine effectiveness (VE) wanes over the course of a temperate climate winter season but little data are available from tropical countries with year-round influenza virus activity. In Singapore, a retrospective cohort study of adults vaccinated from 2013 to 2017 was conducted. Influenza vaccine failure was defined as hospital admission with polymerase chain reaction-confirmed influenza infection 2-49 weeks after vaccination. Relative VE was calculated by splitting the follow-up period into 8-week episodes (Lexis expansion) and the odds of influenza infection in the first 8-week period after vaccination (weeks 2-9) compared with subsequent 8-week periods using multivariable logistic regression adjusting for patient factors and influenza virus activity. Records of 19 298 influenza vaccinations were analysed with 617 (3.2%) influenza infections. Relative VE was stable for the first 26 weeks post-vaccination, but then declined for all three influenza types/subtypes to 69% at weeks 42-49 (95% confidence interval (CI) 52-92%, P = 0.011). VE declined fastest in older adults, in individuals with chronic pulmonary disease and in those who had been previously vaccinated within the last 2 years. Vaccine failure was significantly associated with a change in recommended vaccine strains between vaccination and observation period (adjusted odds ratio 1.26, 95% CI 1.06-1.50, P = 0.010).


Assuntos
Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Humanos , Vigilância da População , Estudos Retrospectivos , Fatores de Tempo , Clima Tropical , Vacinação
13.
BMC Cancer ; 20(1): 1063, 2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33148223

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype with limited systemic treatment options. RX-5902 is a novel anti-cancer agent that inhibits phosphorylated-p68 and thus attenuates nuclear ß-catenin signaling. The purpose of this study was to evaluate the ability of ß-catenin signaling blockade to enhance the efficacy of anti-CTLA-4 and anti-PD-1 immune checkpoint blockade in immunocompetent, preclinical models of TNBC. METHODS: Treatment with RX-5902, anti-PD-1, anti-CTLA-4 or the combination was investigated in BALB/c mice injected with the 4 T1 TNBC cell line. Humanized BALB/c-Rag2nullIl2rγnullSIRPαNOD (hu-CB-BRGS) mice transplanted with a human immune system were implanted with MDA-MB-231 cells. Mice were randomized into treatment groups according to human hematopoietic chimerism and treated with RX-5902, anti-PD-1 or the combination. At sacrifice, bone marrow, lymph nodes, spleen and tumors were harvested for flow cytometry analysis of human immune cells. RESULTS: The addition of RX-5902 to CTLA-4 or PD-1 inhibitors resulted in decreased tumor growth in the 4 T1 and human immune system and MDA-MB-231 xenograft models. Immunologic analyses demonstrated a significant increase in the number of activated T cells in tumor infiltrating lymphocytes (TILs) with RX-5902 treatment compared to vehicle (p < 0.05). In the RX-5902/nivolumab combination group, there was a significant increase in the percentage of CD4+ T cells in TILs and increased systemic granzyme B production (p < 0.01). CONCLUSIONS: Conclusions: RX-5902 enhanced the efficacy of nivolumab in a humanized, preclinical model of TNBC. Several changes in immunologic profiles were noted in mice treated with RX-5902 and the combination, including an increase in activated TILs and a decrease in human myeloid populations, that are often associated with immunosuppression in a tumor microenvironment. RX-5902 also was shown to potentiate the effects of checkpoint inhibitors of CTLA4 and the PD-1 inhibitor in the 4 T-1 murine TNBC model. These findings indicate that RX-5902 may have important immunomodulatory, as well as anti-tumor activity, in TNBC when combined with a checkpoint inhibitor.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Checkpoint Imunológico/farmacologia , Linfócitos do Interstício Tumoral/imunologia , Piperazinas/farmacologia , Quinoxalinas/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Microambiente Tumoral/imunologia , beta Catenina/antagonistas & inibidores , Animais , Apoptose , Proliferação de Células , Quimioterapia Combinada , Feminino , Humanos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Células Tumorais Cultivadas , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
14.
Public Health ; 185: 338-340, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32726730

RESUMO

OBJECTIVES: There is a need to improve efficiency in healthcare delivery without compromising quality of care. One approach is the development and evaluation of behavioural strategies to reduce unnecessary use of common tests. However, there is an absence of evidence on patient attitudes to the use of such approaches in the delivery of care. Our objective was to explore patient acceptability of a nudge-type intervention that aimed to modify blood test requests by hospital doctors. STUDY DESIGN: Single-centre qualitative study. METHODS: The financial costs of common blood tests were presented to hospital doctors on results reports for 1 year at a hospital. Focus group discussions were conducted with recent inpatients at the hospital using a semi-structured question schedule. Discussions were transcribed and analysed using qualitative content analysis to identify and prioritise common themes explaining attitudes to the intervention approach. RESULTS: Three focus groups involving 17 participants were conducted. Patients were generally apprehensive about the provision of blood test cost feedback to doctors. Attitudes were organised around themes representing beliefs about blood tests, the impact on doctors and their autonomy, and beliefs about unnecessary testing. Patients thought that blood tests were important, powerful and inexpensive, and cost information could place doctors under additional pressure. CONCLUSION: The findings identify predominantly positive beliefs about testing and negative attitudes to the use of financial costs in the decision-making of hospital doctors. Public discussion and education about the possible overuse of common tests may allow more resources to be allocated to evidence-based healthcare, by reducing the perception that such strategies to improve healthcare efficiency negatively impact on quality of care.


Assuntos
Atitude Frente a Saúde , Atenção à Saúde/economia , Testes Hematológicos/psicologia , Retroalimentação , Feminino , Grupos Focais , Custos de Cuidados de Saúde , Pessoal de Saúde , Testes Hematológicos/economia , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Médicos , Pesquisa Qualitativa
15.
Int J Mol Sci ; 21(8)2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32295203

RESUMO

(1) Background: RX-3117 (fluorocyclopentenyl-cytosine) is a cytidine analog that inhibits DNA methyltransferase 1 (DNMT1). We investigated the mechanism and potential of RX-3117 as a demethylating agent in several in vitro models. (2) Methods: we used western blotting to measure expression of several proteins known to be down-regulated by DNA methylation: O6-methylguanine-DNA methyltransferase (MGMT) and the tumor-suppressor genes, p16 and E-cadherin. Transport of methotrexate (MTX) mediated by the proton-coupled folate transporter (PCFT) was used as a functional assay. (3) Results: RX-3117 treatment decreased total DNA-cytosine-methylation in A549 non-small cell lung cancer (NSCLC) cells, and induced protein expression of MGMT, p16 and E-cadherin in A549 and SW1573 NSCLC cells. Leukemic CCRF-CEM cells and the MTX-resistant variant (CEM/MTX, with a deficient reduced folate carrier) have a very low expression of PCFT due to promoter hypermethylation. In CEM/MTX cells, pre-treatment with RX-3117 increased PCFT-mediated MTX uptake 8-fold, and in CEM cells 4-fold. With the reference hypomethylating agent 5-aza-2'-deoxycytidine similar values were obtained. RX-3117 also increased PCFT gene expression and PCFT protein. (4) Conclusion: RX-3117 down-regulates DNMT1, leading to hypomethylation of DNA. From the increased protein expression of tumor-suppressor genes and functional activation of PCFT, we concluded that RX-3117 might have induced hypomethylation of the promotor.


Assuntos
Citidina/análogos & derivados , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Transportador de Folato Acoplado a Próton/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Linhagem Celular Tumoral , Citidina/farmacologia , DNA (Citosina-5-)-Metiltransferase 1/genética , Metilação de DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Metotrexato/farmacologia , Transportador de Folato Acoplado a Próton/genética , Proteínas Supressoras de Tumor/genética
16.
Br J Surg ; 107(8): 1013-1022, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32181505

RESUMO

BACKGROUND: Research studies to inform clinical practice and policy in children and young people with appendicitis are hampered by inconsistent selection and reporting of outcomes. The aim of this study was to develop a core outcome set for reporting all studies of uncomplicated acute appendicitis in children and young people. METHODS: Systematic literature reviews, qualitative interviews with parents and patients treated for uncomplicated acute appendicitis, and a Study-Specific Advisory Group informed a long list of outcomes. Outcomes were then prioritized by stakeholders based in the UK (patients, parents, and paediatric and general surgeons) in an online three-round Delphi consensus process, followed by face-to-face consensus meetings. RESULTS: A long list of 40 items was scored by 147 key stakeholders in the first Delphi round, of whom 90 completed the two subsequent Delphi rounds. The final core outcome set comprises 14 outcomes: intra-abdominal abscess, reoperation (including interventional radiology procedure), readmission to hospital, bowel obstruction, wound infection, antibiotic failure, wound complication, negative appendicectomy, recurrent appendicitis, death, patient stress/psychological distress, length of hospital stay, time away from full activity and child's quality of life. CONCLUSION: A core outcome set comprising 14 outcomes across five key domains has been developed for reporting studies in children and young people with uncomplicated acute appendicitis. Further work is required to determine how and when to measure these outcomes.


ANTECEDENTES: Los estudios de investigación que sirvan de base para la práctica clínica y la política en niños y adultos jóvenes con apendicitis se ven obstaculizados por inconsistencias en la selección y descripción de los resultados. El objetivo de este estudio fue desarrollar un conjunto central de resultados para todos los estudios de apendicitis aguda no complicada en niños y adultos jóvenes. MÉTODOS: Para establecer una lista de resultados se efectuaron revisiones sistemáticas de la literatura, entrevistas cualitativas con padres y pacientes tratados por apendicitis aguda no complicada, y consulta con un Grupo de Asesoramiento Específico para el Estudio. Seguidamente, los resultados se priorizaron de acuerdo con los intereses de las partes interesadas (pacientes, padres, y cirujanos pediátricos y generales) en el Reino Unido a través de un proceso de consenso Delphi de tres rondas en Internet, seguido de reuniones personales de consenso. RESULTADOS: Un total de 147 participantes puntuaron una larga lista de 40 ítems en la primera ronda Delphi, de los cuales 90 completaron las dos rondas Delphi subsiguientes. El conjunto final incluye 14 resultados: absceso intra-abdominal, reoperación (incluyendo procedimientos radiológicos intervencionistas), reingreso, obstrucción intestinal, infección de herida, otras complicaciones de la herida, fracaso del tratamiento con antibióticos, apendicectomía blanca, apendicitis recidivante, muerte, estrés del paciente/sufrimiento psicológico, duración de la estancia hospitalaria, tiempo alejado de todas sus actividades y calidad de vida. CONCLUSIÓN: Se ha desarrollado un conjunto central de resultados que incluye 14 resultados en cinco dominios clave para la descripción de estudios en niños y adultos jóvenes con apendicitis aguda no complicada. Se requieren más trabajos para determinar cómo y cuándo conviene medir estos resultados.


Assuntos
Apendicite/terapia , Avaliação de Resultados em Cuidados de Saúde/métodos , Doença Aguda , Adolescente , Apendicectomia , Apendicite/diagnóstico , Criança , Pré-Escolar , Consenso , Técnica Delphi , Humanos , Tempo de Internação , Complicações Pós-Operatórias , Recidiva
18.
Nucleic Acids Res ; 48(1): 130-140, 2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31713617

RESUMO

Charcot-Marie-Tooth 1A (CMT1A) is the most common inherited neuropathy without a known therapy, which is caused by a 1.4 Mb duplication on human chromosome 17, which includes the gene encoding the peripheral myelin protein of 22 kDa (PMP22). Overexpressed PMP22 protein from its gene duplication is thought to cause demyelination and subsequently axonal degeneration in the peripheral nervous system (PNS). Here, we targeted TATA-box of human PMP22 promoter to normalize overexpressed PMP22 level in C22 mice, a mouse model of CMT1A harboring multiple copies of human PMP22. Direct local intraneural delivery of CRISPR/Cas9 designed to target TATA-box of PMP22 before the onset of disease, downregulates gene expression of PMP22 and preserves both myelin and axons. Notably, the same approach was effective in partial rescue of demyelination even after the onset of disease. Collectively, our data present a proof-of-concept that CRISPR/Cas9-mediated targeting of TATA-box can be utilized to treat CMT1A.


Assuntos
Doença de Charcot-Marie-Tooth/terapia , Terapia de Alvo Molecular/métodos , Proteínas da Mielina/genética , Bainha de Mielina/metabolismo , Células de Schwann/metabolismo , TATA Box , Animais , Axônios , Sistemas CRISPR-Cas , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/metabolismo , Doença de Charcot-Marie-Tooth/patologia , Duplicação Cromossômica , Cromossomos Humanos Par 17 , Modelos Animais de Doenças , Edição de Genes/métodos , Humanos , Injeções , Camundongos , Proteínas da Mielina/metabolismo , Bainha de Mielina/patologia , Cultura Primária de Células , Regiões Promotoras Genéticas , Células de Schwann/patologia , Nervo Isquiático/metabolismo , Nervo Isquiático/patologia
19.
J Biomed Opt ; 24(9): 1-11, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31564072

RESUMO

Minimally invasive robotic surgery using fluorescence-guided images with a video laparoscope has been widely used because of its advantages of small incision, fast recovery time, and efficiency. However, the penetration depth limitation of fluorescence is a disadvantage caused by the absorption and scattering in tissues and blood cells. If this limitation can be overcome by additional imaging modalities, the surgical procedure can be quite efficient and precise. High-energy annihilation-gamma photons have a stronger penetration capability than visible and fluorescence photons. To characterize and validate a multimodal annihilation-gamma/near-infrared (NIR)/visible laparoscopic imaging system, an internal detector composed of an annihilation-gamma detector and an optical system was assembled inside a surgical stainless pipe with an outer diameter of 15.8 mm and an external detector with a dimension of 100 × 100 mm2 placed at the opposite side of the internal detector. Integrated images of 511-keV gamma rays, NIR fluorescence, and visible light were obtained simultaneously. The 511-keV gamma image could be clearly seen with the acquisition of 5 s, while NIR and visible images could be presented in real time. This multimodal system has the potential for improving the surgery time and the quality of patient care.


Assuntos
Laparoscopia/métodos , Imagem Multimodal/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Desenho de Equipamento , Verde de Indocianina , Imagens de Fantasmas , Procedimentos Cirúrgicos Robóticos/métodos , Processamento de Sinais Assistido por Computador
20.
Mol Cancer Ther ; 18(11): 1916-1925, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31488700

RESUMO

RX-5902 is a first-in-class anticancer agent targeting phosphorylated-p68 and attenuating nuclear shuttling of ß-catenin. The purpose of this study was to evaluate the efficacy of RX-5902 in preclinical models of triple-negative breast cancer (TNBC) and to explore effects on ß-catenin expression. A panel of 18 TNBC cell lines was exposed to RX-5902, and changes in proliferation, apoptosis, cellular ploidy, and effector protein expression were assessed. Gene expression profiling was used in sensitive and resistant cell lines with pathway analysis to explore pathways associated with sensitivity to RX-5902. The activity of RX-5902 was confirmed in vivo in cell line and patient-derived tumor xenograft (PDX) models. RX-5902 demonstrated potent antiproliferative activity in vitro against TNBC cell lines with an average IC50 of 56 nmol/L in sensitive cell lines. RX-5902 treatment resulted in the induction of apoptosis, G2-M cell-cycle arrest, and aneuploidy in a subset of cell lines. RX-5902 was active in vivo against TNBC PDX models, and treatment resulted in a decrease in nuclear ß-catenin. RX-5902 exhibited dose-proportional pharmacokinetics and plasma and tumor tissue in nude mice. Pathway analysis demonstrated an increase in the epithelial-to-mesenchymal transformation (EMT), TGFß, and Wnt/ß-catenin pathways associated with sensitivity to RX-5902. RX-5902 is active against in vitro and in vivo preclinical models of TNBC. Target engagement was confirmed with decreases in nuclear ß-catenin and MCL-1 observed, confirming the proposed mechanism of action. This study supports the continued investigation of RX-5902 in TNBC and combinations with immunotherapy.


Assuntos
Antineoplásicos/administração & dosagem , Piperazinas/administração & dosagem , Quinoxalinas/administração & dosagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Via de Sinalização Wnt/efeitos dos fármacos , eIF-2 Quinase/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fosforilação , Piperazinas/farmacologia , Quinoxalinas/farmacologia , Neoplasias de Mama Triplo Negativas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
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