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1.
Proc Natl Acad Sci U S A ; 120(4): e2204098120, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36656853

RESUMO

The scale and pace of energy infrastructure development required to achieve net-zero greenhouse gas (GHG) emissions are unprecedented, yet our understanding of how to minimize its potential impacts on land and ocean use and natural resources is inadequate. Using high-resolution energy and land-use modeling, we developed spatially explicit scenarios for reaching an economy-wide net-zero GHG target in the western United States by 2050. We found that among net-zero policy cases that vary the rate of transportation and building electrification and use of fossil fuels, nuclear generation, and biomass, the "High Electrification" case, which utilizes electricity generation the most efficiently, had the lowest total land and ocean area requirements (84,000 to 105,000 km2 vs. 88,100 to 158,000 km2 across all other cases). Different levels of land and ocean use protections were applied to determine their effect on siting, environmental and social impacts, and energy costs. Meeting the net-zero target with stronger land and ocean use protections did not significantly alter the share of different energy generation technologies and only increased system costs by 3%, but decreased additional interstate transmission capacity by 20%. Yet, failure to avoid development in areas with high conservation value is likely to result in substantial habitat loss.

2.
Biomacromolecules ; 25(2): 1310-1318, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38265878

RESUMO

Although the formation of peptide assemblies catalyzed by alkaline phosphatase (ALP) has received increasing attention in inhibiting cancer cells, the detailed enzyme kinetics of the dephosphorylation of the corresponding phosphopeptide assemblies have yet to be determined. We recently discovered that assemblies from a phosphopentapeptide can form intracellular nanoribbons that kill induced pluripotent stem cells or osteosarcoma cells, but the kinetics of enzymatic dephosphorylation remain unknown. Thus, we chose to examine the enzyme kinetics of the dephosphorylation of the phosphopentapeptide [NBD-LLLLpY (1)] from concentrations below to above its critical micelle concentration (CMC). Our results show that the phosphopeptide exhibits a CMC of 75 µM in phosphate saline buffer, and the apparent Vmax and Km values of alkaline phosphatase catalyzed dephosphorylation are approximately 0.24 µM/s and 5.67 mM, respectively. Despite dephosphorylation remaining incomplete at 60 min in all the concentrations tested, dephosphorylation of the phosphopeptide at concentrations of 200 µM or above mainly results in nanoribbons, dephosphorylation at concentrations of CMC largely produces nanofibers, and dephosphorylation below the CMC largely generates nanoparticles. Moreover, the formation of nanoribbons correlates with the intranuclear accumulation of the pentapeptide. By providing the first examination of the enzymatic kinetics of phosphopeptide assemblies, this work further supports the notion that the assemblies of phosphopentapeptides can act as a new functional entity for controlling cell fates.


Assuntos
Nanotubos de Carbono , Fosfopeptídeos , Fosfatase Alcalina/metabolismo , Cinética
3.
J Infect Dis ; 228(Suppl 3): S180-S188, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37703347

RESUMO

The estimated prevalence of anti-HCV was 3.1% in Taiwan. Studies have shown iatrogenic behavior was the major transmission route. It is highest in specific populations including patients with end stage renal disease (ESRD), human immunodeficiency virus infection, who inject drug (PWID), and under opioid substitution treatment. Approximately 405,160 patients were seropositive for HCV RNA and in need of treatment. Taiwan government claims to reach WHO's 2030 goal of HCV elimination by 2025 and works hard to resolve several barriers of HCV elimination including political commitment, sustainable financing, minimize reimbursement restrictions, instituted monitoring, and perform micro-elimination of specific populations. The last stage of HCV elimination is to accelerate the universal HCV screening program of populations aged 45-79 years and resolve the unawareness issue of HCV infection. Hopefully, we can achieve the targets of HCV elimination set by WHO and reach the goal earlier in 2025.


Assuntos
Hepacivirus , Hepatite C , Humanos , Hepacivirus/genética , Taiwan/epidemiologia , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Políticas , Governo
4.
Nature ; 534(7605): 106-10, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27251285

RESUMO

The wing patterns of butterflies and moths (Lepidoptera) are diverse and striking examples of evolutionary diversification by natural selection. Lepidopteran wing colour patterns are a key innovation, consisting of arrays of coloured scales. We still lack a general understanding of how these patterns are controlled and whether this control shows any commonality across the 160,000 moth and 17,000 butterfly species. Here, we use fine-scale mapping with population genomics and gene expression analyses to identify a gene, cortex, that regulates pattern switches in multiple species across the mimetic radiation in Heliconius butterflies. cortex belongs to a fast-evolving subfamily of the otherwise highly conserved fizzy family of cell-cycle regulators, suggesting that it probably regulates pigmentation patterning by regulating scale cell development. In parallel with findings in the peppered moth (Biston betularia), our results suggest that this mechanism is common within Lepidoptera and that cortex has become a major target for natural selection acting on colour and pattern variation in this group of insects.


Assuntos
Mimetismo Biológico/genética , Borboletas/genética , Genes de Insetos/genética , Pigmentação/genética , Asas de Animais/fisiologia , Animais , Mimetismo Biológico/fisiologia , Borboletas/citologia , Borboletas/fisiologia , Cor , Evolução Molecular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Fenótipo , Pigmentação/fisiologia , Seleção Genética/genética
5.
Am J Transplant ; 21(7): 2522-2531, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33443778

RESUMO

We compared the outcome of COVID-19 in immunosuppressed solid organ transplant (SOT) patients to a transplant naïve population. In total, 10 356 adult hospital admissions for COVID-19 from March 1, 2020 to April 27, 2020 were analyzed. Data were collected on demographics, baseline clinical conditions, medications, immunosuppression, and COVID-19 course. Primary outcome was combined death or mechanical ventilation. We assessed the association between primary outcome and prognostic variables using bivariate and multivariate regression models. We also compared the primary endpoint in SOT patients to an age, gender, and comorbidity-matched control group. Bivariate analysis found transplant status, age, gender, race/ethnicity, body mass index, diabetes, hypertension, cardiovascular disease, COPD, and GFR <60 mL/min/1.73 m2 to be significant predictors of combined death or mechanical ventilation. After multivariate logistic regression analysis, SOT status had a trend toward significance (odds ratio [OR] 1.29; 95% CI 0.99-1.69, p = .06). Compared to an age, gender, and comorbidity-matched control group, SOT patients had a higher combined risk of death or mechanical ventilation (OR 1.34; 95% CI 1.03-1.74, p = .027).


Assuntos
COVID-19 , Transplante de Órgãos , Adulto , Humanos , Terapia de Imunossupressão , SARS-CoV-2 , Transplantados
6.
Ann Surg Oncol ; 28(13): 8318-8328, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34312800

RESUMO

BACKGROUND: Ampullary neuroendocrine tumors (NETs) make up < 1% of all gastroenteropancreatic NETs, and information is limited to case series. This study compares patients with ampullary, duodenal, and pancreatic head NETs. METHODS: The National Cancer Database (2004-2016) was queried for patients with ampullary, duodenal, and pancreatic head NETs. Survival was evaluated using Kaplan-Meier analysis and Cox regression. RESULTS: Overall, 872, 9692, and 6561 patients were identified with ampullary, duodenal, and pancreatic head NETs, respectively. Patients with ampullary NETs had more grade 3 tumors (n = 149, 17%) than patients with duodenal (n = 197, 2%) or pancreatic head (n = 740, 11%) NETs. Patients with ampullary NETs had more positive lymph nodes (n = 297, 34%) than patients with duodenal (n = 950, 10%) or pancreatic head (n = 1513, 23%) NETs. On multivariable analysis for patients with ampullary NETs, age (hazard ratio [HR] 1.03, p < 0.0001), Charlson-Deyo score of 2 (HR 2.3, p = 0.001) or ≥3 (HR 2.9, p = 0.013), grade 2 (HR 1.9, p = 0.007) or grade 3 tumors (HR 4.0, p < 0.0001), and metastatic disease (HR 2.0, p = 0.001) were associated with decreased survival. At 5 years, the overall survival (OS) for patients with ampullary, duodenal, and pancreatic head NETs was 59%, 71%, and 50%, respectively (p < 0.0001), whereas the 5-year OS for patients with ampullary, duodenal, and pancreatic head NETs who underwent surgery was 62%, 78%, and 76%, respectively (p < 0.0001). CONCLUSIONS: Ampullary NETs were more likely to present with high-grade tumors and lymph node metastases. Based on the clinicopathologic and survival data, ampullary NETs have a unique underlying biology compared with duodenal and pancreatic head NETs.


Assuntos
Neoplasias do Ducto Colédoco , Neoplasias Duodenais , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Neoplasias do Ducto Colédoco/cirurgia , Neoplasias Duodenais/cirurgia , Humanos , Tumores Neuroendócrinos/cirurgia , Modelos de Riscos Proporcionais
7.
J Formos Med Assoc ; 120(7): 1444-1451, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33516585

RESUMO

BACKGROUND/PURPOSE: This study aims at investigating the epidemiological profile of chronic hepatitis C (CHC) regarding hepatitis C virus (HCV) genotype in Taiwan. METHODS: A total of 29,087 CHC patients with advanced fibrosis who received direct-acting antivirals (DAAs) therapy under Taiwan's National Health Insurance (NHI) during 2017-2018 were recruited. The HCV genotype distribution and its association with patients' demographic factors including age, gender, and geographical areas were examined. RESULTS: The most common genotypes were 1b (59.5%) and 2 (30.1%) with characteristics of older age (mean ± standard deviation (SD): 66.5 ± 10.7 years and 67.3 ± 10.9 years) and female gender predominant (57.1% and 59.4%), which were associated with iatrogenic infection decades ago. Most of patients with genotype 1a (5.9%) and 6 (3.7%) infection were relatively younger (59.2 ± 12.0 years and 60.0 ± 13.8 years) and male gender predominant (59.1% and 61.1%), except Liujia and Liuying districts in southern Taiwan. The youngest group (53.2 ± 11.8 years) and most male gender predominant (74.3%) was genotype 3 (0.37%). These genotypes with characteristics of being younger and male gender predominant were highly related to injection drug use in recent years. The number of genotype 4 patients were extremely rare (n = 25) and efficacy of genotype-4-specific-DAA was significantly poorer than non-genotype-4-specific DAA (P value = 0.0411). CONCLUSION: The significant differences in demographic characteristics among CHC patients with different HCV genotypes found in this study suggest HCV genotype was highly associated with transmission pattern and may be used as a reference for HCV control.


Assuntos
Hepatite C Crônica , Hepatite C , Idoso , Antivirais/uso terapêutico , Feminino , Fibrose , Genótipo , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Humanos , Cirrose Hepática/epidemiologia , Masculino , Taiwan/epidemiologia
8.
Proc Natl Acad Sci U S A ; 114(15): E3004-E3012, 2017 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-28348209

RESUMO

Recent forecasts suggest that African countries must triple their current electricity generation by 2030. Our multicriteria assessment of wind and solar potential for large regions of Africa shows how economically competitive and low-environmental-impact renewable resources can significantly contribute to meeting this demand. We created the Multicriteria Analysis for Planning Renewable Energy (MapRE) framework to map and characterize solar and wind energy zones in 21 countries in the Southern African Power Pool (SAPP) and the Eastern Africa Power Pool (EAPP) and find that potential is several times greater than demand in many countries. Significant fractions of demand can be quickly served with "no-regrets" options-or zones that are low-cost, low-environmental impact, and highly accessible. Because no-regrets options are spatially heterogeneous, international interconnections are necessary to help achieve low-carbon development for the region as a whole, and interconnections that support the best renewable options may differ from those planned for hydropower expansion. Additionally, interconnections and selecting wind sites to match demand reduce the need for SAPP-wide conventional generation capacity by 9.5% in a high-wind scenario, resulting in a 6-20% cost savings, depending on the avoided conventional technology. Strategic selection of low-impact and accessible zones is more cost effective with interconnections compared with solutions without interconnections. Overall results are robust to multiple load growth scenarios. Together, results show that multicriteria site selection and deliberate planning of interconnections may significantly increase the economic and environmental competitiveness of renewable alternatives relative to conventional generation.

9.
Proc Natl Acad Sci U S A ; 112(44): 13579-84, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26483467

RESUMO

Decisions determining the use of land for energy are of exigent concern as land scarcity, the need for ecosystem services, and demands for energy generation have concomitantly increased globally. Utility-scale solar energy (USSE) [i.e., ≥ 1 megawatt (MW)] development requires large quantities of space and land; however, studies quantifying the effect of USSE on land cover change and protected areas are limited. We assessed siting impacts of >160 USSE installations by technology type [photovoltaic (PV) vs. concentrating solar power (CSP)], area (in square kilometers), and capacity (in MW) within the global solar hot spot of the state of California (United States). Additionally, we used the Carnegie Energy and Environmental Compatibility model, a multiple criteria model, to quantify each installation according to environmental and technical compatibility. Last, we evaluated installations according to their proximity to protected areas, including inventoried roadless areas, endangered and threatened species habitat, and federally protected areas. We found the plurality of USSE (6,995 MW) in California is sited in shrublands and scrublands, comprising 375 km(2) of land cover change. Twenty-eight percent of USSE installations are located in croplands and pastures, comprising 155 km(2) of change. Less than 15% of USSE installations are sited in "Compatible" areas. The majority of "Incompatible" USSE power plants are sited far from existing transmission infrastructure, and all USSE installations average at most 7 and 5 km from protected areas, for PV and CSP, respectively. Where energy, food, and conservation goals intersect, environmental compatibility can be achieved when resource opportunities, constraints, and trade-offs are integrated into siting decisions.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Modelos Teóricos , Energia Solar , Animais , California , Espécies em Perigo de Extinção , Geografia , Humanos
10.
J Card Fail ; 22(9): 692-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26721774

RESUMO

BACKGROUND: Procollagen type III N-terminal peptide (PIIINP) is a biomarker of cardiac fibrosis that is associated with heart failure prognosis in whites. Its prognostic significance in African Americans is unknown. We sought to determine whether PIIINP is associated with outcomes in African Americans with heart failure. METHODS AND RESULTS: Blood was collected from 138 African Americans with heart failure for determining PIIINP and genetic ancestry, and patients were followed prospectively for death or hospitalization for heart failure. PIIINP was inversely correlated with West African ancestry (R(2) = 0.061; P = .010). PIIINP > 4.88 ng/mL was associated with all-cause mortality on univariate (hazard ratio [HR] 4.9, 95% confidence interval [CI] 2.2-11.0; P < .001) and multivariate (HR 5.8; 95% CI 1.9-17.3; P = .002) analyses over a median follow-up period of 3 years. We also observed an increased risk for the combined outcome of all-cause mortality or hospitalization for heart failure with PIIINP > 4.88 ng/mL on univariate (HR 2.6, 95% CI 1.6-5.0; P < .001) and multivariate (HR 2.4, 95% CI 1.2-4.7; P = .016) analyses. CONCLUSIONS: High circulating PIIINP is associated with poor outcomes in African Americans with chronic heart failure, suggesting that PIIINP may be useful in identifying African Americans who may benefit from additional therapy to combat fibrosis as a means of improving prognosis.


Assuntos
Negro ou Afro-Americano/genética , Causas de Morte , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/mortalidade , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Doença Aguda , Adulto , Fatores Etários , Idoso , Análise de Variância , Biomarcadores/sangue , Estudos de Coortes , Feminino , Insuficiência Cardíaca/etnologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Estudos Retrospectivos , Medição de Risco , Fatores Sexuais , Análise de Sobrevida
11.
Ecol Appl ; 26(4): 1154-69, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27509755

RESUMO

Species distribution models (SDMs) have been criticized for involving assumptions that ignore or categorize many ecologically relevant factors such as dispersal ability and biotic interactions. Another potential source of model error is the assumption that species are ecologically uniform in their climatic tolerances across their range. Typically, SDMs treat a species as a single entity, although populations of many species differ due to local adaptation or other genetic differentiation. Not taking local adaptation into account may lead to incorrect range prediction and therefore misplaced conservation efforts. A constraint is that we often do not know the degree to which populations are locally adapted. Lacking experimental evidence, we still can evaluate niche differentiation within a species' range to promote better conservation decisions. We explore possible conservation implications of making type I or type II errors in this context. For each of two species, we construct three separate Max-Ent models, one considering the species as a single population and two of disjunct populations. Principal component analyses and response curves indicate different climate characteristics in the current environments of the populations. Model projections into future climates indicate minimal overlap between areas predicted to be climatically suitable by the whole species vs. population-based models. We present a workflow for addressing uncertainty surrounding local adaptation in SDM application and illustrate the value of conducting population-based models to compare with whole-species models. These comparisons might result in more cautious management actions when alternative range outcomes are considered.


Assuntos
Adaptação Fisiológica/fisiologia , Borboletas/fisiologia , Mudança Climática , Conservação dos Recursos Naturais/métodos , Modelos Biológicos , Primula/fisiologia , Animais , Espécies em Perigo de Extinção , Monitoramento Ambiental , Dinâmica Populacional
13.
Environ Sci Technol ; 49(4): 2013-21, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25541644

RESUMO

The land-use implications of deep decarbonization of the electricity sector (e.g., 80% below 1990 emissions) have not been well-characterized quantitatively or spatially. We assessed the operational-phase land-use requirements of different low-carbon scenarios for California in 2050 and found that most scenarios have comparable direct land footprints. While the per MWh footprint of renewable energy (RE) generation is initially higher, that of fossil and nuclear generation increases over time with continued fuel use. We built a spatially explicit model to understand the interactions between resource quality and environmental constraints in a high RE scenario (>70% of total generation). We found that there is sufficient land within California to meet the solar and geothermal targets, but areas with the highest quality wind and solar resources also tend to be those with high conservation value. Development of some land with lower conservation value results in lower average capacity factors, but also provides opportunity for colocation of different generation technologies, which could significantly improve land-use efficiency and reduce permitting, leasing, and transmission infrastructure costs. Basing siting decisions on environmentally-constrained long-term RE build-out requirements produces significantly different results, including better conservation outcomes, than implied by the current piecemeal approach to planning.


Assuntos
Conservação de Recursos Energéticos/economia , Conservação de Recursos Energéticos/métodos , Política Ambiental/economia , Energia Renovável/estatística & dados numéricos , California , Carbono/análise , Conservação dos Recursos Naturais , Eletricidade , Meio Ambiente , Energia Geotérmica , Vento
14.
Mol Ecol ; 23(11): 2686-98, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24766086

RESUMO

Local adaptation of populations could preclude or slow range expansions in response to changing climate, particularly when dispersal is limited. To investigate the differential responses of populations to changing climatic conditions, we exposed poleward peripheral and central populations of two Lepidoptera to reciprocal, common-garden climatic conditions and compared their whole-transcriptome expression. We found evidence of simple population differentiation in both species, and in the species with previously identified population structure and phenotypic local adaptation, we found several hundred genes that responded in a synchronized and localized fashion. These genes were primarily involved in energy metabolism and oxidative stress, and expression levels were most divergent between populations in the same environment in which we previously detected divergence for metabolism. We found no localized genes in the species with less population structure and for which no local adaptation was previously detected. These results challenge the assumption that species are functionally similar across their ranges and poleward peripheral populations are preadapted to warmer conditions. Rather, some taxa deserve population-level consideration when predicting the effects of climate change because they respond in genetically based, distinctive ways to changing conditions.


Assuntos
Aclimatação/genética , Mudança Climática , Genética Populacional , Lepidópteros/genética , Animais , Feminino , Expressão Gênica , Lepidópteros/classificação , Dados de Sequência Molecular , América do Norte , Dinâmica Populacional , Especificidade da Espécie , Temperatura , Transcriptoma
15.
Anal Biochem ; 449: 147-54, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24361717

RESUMO

Reagent storage has been a long-standing challenge for diagnostics, especially those designed for low-resource settings and point-of-care applications. In general, the stability of a reagent relies on careful temperature control, often by refrigeration, which is costly and often unavailable in these remote settings. Poor reagent integrity can negatively affect the reproducibility and reliability of an assay. Given the recent interest in paper-based devices designed for quantitative analysis in point-of-care settings, a better understanding of reagent stability on filter paper is critical for proper device use and its longevity. In this article, we present an independent method to examine the stability of reconstituted antibodies that were stored on filter paper using flow cytometry. We validated the method by measuring the activity as measured by the mean fluorescence intensity (MFI) of antibodies stored with known stabilizers. Furthermore, we demonstrated the potential of our method to screen the influence of other paper treatments and storage processes on antibody stability, which may be applicable to the storage of reagents on paper in general.


Assuntos
Anticorpos/química , Fluoresceína/química , Papel , Estabilidade Proteica , Animais , Anticorpos/imunologia , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática , Excipientes/química , Citometria de Fluxo , Humanos , Imunoglobulina G/química , Imunoglobulina G/imunologia , Indicadores e Reagentes , Cadeias beta de Integrinas/análise , Cadeias beta de Integrinas/imunologia , Interleucina-4/análise , Interleucina-4/imunologia , Filtros Microporos , Preservação Biológica
16.
Bioinform Adv ; 4(1): vbae047, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38606185

RESUMO

Motivation: Predicting anticancer treatment response from baseline genomic data is a critical obstacle in personalized medicine. Machine learning methods are commonly used for predicting drug response from gene expression data. In the process of constructing these machine learning models, one of the most significant challenges is identifying appropriate features among a massive number of genes. Results: In this study, we utilize features (genes) extracted using the text-mining of scientific literatures. Using two independent cancer pharmacogenomic datasets, we demonstrate that text-mining-based features outperform traditional feature selection techniques in machine learning tasks. In addition, our analysis reveals that text-mining feature-based machine learning models trained on in vitro data also perform well when predicting the response of in vivo cancer models. Our results demonstrate that text-mining-based feature selection is an easy to implement approach that is suitable for building machine learning models for anticancer drug response prediction. Availability and implementation: https://github.com/merlab/text_features.

17.
Drug Saf ; 47(4): 289-299, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38113017

RESUMO

Health technology assessment (HTA) is a multidisciplinary process that determines the value of health technology at different points in its lifecycle. Safety issues have become more important since regulatory authorities are increasingly adopting flexible standards, processes, and evidentiary requirements for drug approval. In this article, we compared the different role of regulatory authorities and HTA agencies. Additionally, the experience of regulatory-HTA collaboration for assessment and/or decision-making on safety issues in the lifecycle of a health technology is illustrated, including olmesartan (angiotensin II receptor antagonist) and the direct-acting hepatitis C virus (HCV) antiviral agents. Post-licensing data can be derived from various sources such as electronic health records, medical claims, drug and disease registries, post-authorization safety studies (PASS) or post-authorization safety efficacy studies (PAES), periodic benefit-risk assessment reports, as well as HTA reassessment reports, which incorporate utilization information from patients in a real-world setting and provide crucial evidence for various purposes. With the ongoing accumulation of safety and efficacy information during post-regulatory approval, a standardized process for continuous data collection and active reassessment of risk and benefit becomes crucial for managing the lifecycle of health technologies. In order to define evidence requirements clearly, reduce uncertainty, and minimize delays in HTA approval, early engagement and collaboration of HTA agencies in the regulatory review processes have become more common. However, there is currently limited interaction and collaboration between regulatory authorities and HTA agencies. This article aims to identify the challenges faced by regulators and HTA agencies today, emphasizing the significance of conducting regulatory reviews and health technology assessments throughout a technology's lifecycle, underlining the value of utilizing real-world data and evidence, and emphasizing the necessity of enhancing collaboration between regulatory authorities and HTA agencies, all within the overarching context of drug safety.


Assuntos
Aprovação de Drogas , Avaliação da Tecnologia Biomédica , Humanos , Incerteza , Coleta de Dados , Pacientes
18.
Nat Commun ; 15(1): 1083, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316824

RESUMO

The scale at which low-carbon electricity will need to be deployed to meet economic growth, electrification, and climate goals in Africa is unprecedented, yet the potential land use and freshwater impacts from this massive build-out of energy infrastructure is poorly understood. In this study, we characterize low-impact onshore wind, solar photovoltaics, and hydropower potential in Southern Africa and identify the cost-optimal mix of electricity generation technologies under different sets of socio-environmental land use and freshwater constraints and carbon targets. We find substantial wind and solar potential after applying land use protections, but about 40% of planned or proposed hydropower projects face socio-environmental conflicts. Applying land and freshwater protections results in more wind, solar, and battery capacity and less hydropower capacity compared to scenarios without protections. While a carbon target favors hydropower, the amount of cost-competitively selected hydropower is at most 45% of planned or proposed hydropower capacity in any scenario-and is only 25% under socio-environmental protections. Achieving both carbon targets and socio-environmental protections results in system cost increases of 3-6%. In the absence of land and freshwater protections, environmental and social impacts from new hydropower development could be significant.

19.
ACS Appl Mater Interfaces ; 16(21): 27705-27713, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38748054

RESUMO

Vascular stenting is a common procedure used to treat diseased blood vessels by opening the narrowed vessel lumen and restoring blood flow to ischemic tissues in the heart and other organs. In this work, we report a novel piezoelectric stent featuring a zigzag shape fabricated by fused deposition modeling three-dimensional (3D) printing with a built-in electric field. The piezoelectric composite was made of potassium sodium niobite microparticles and poly(vinylidene fluoride-co-hexafluoropropylene), complementing each other with good piezoelectric performance and mechanical resilience. The in situ poling yielded an appreciable piezoelectricity (d33 ∼ 4.2 pC N-1) of the as-printed stents. In vitro testing revealed that materials are nontoxic to vascular cells and have low thrombotic potential. Under stimulated blood pressure fluctuation, the as-printed piezoelectric stent was able to generate peak-to-peak voltage from 0.07 to 0.15 V corresponding to pressure changes from 20 to 120 Psi, giving a sensitivity of 7.02 × 10-4 V Psi-1. Biocompatible piezoelectric stents bring potential opportunities for the real-time monitoring of blood vessels or enabling therapeutic functions.


Assuntos
Impressão Tridimensional , Stents , Humanos , Eletricidade , Pressão , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Polivinil/química
20.
Nat Med ; 12(7): 793-800, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16799557

RESUMO

Vascular endothelial growth factor (VEGF) exerts crucial functions during pathological angiogenesis and normal physiology. We observed increased hematocrit (60-75%) after high-grade inhibition of VEGF by diverse methods, including adenoviral expression of soluble VEGF receptor (VEGFR) ectodomains, recombinant VEGF Trap protein and the VEGFR2-selective antibody DC101. Increased production of red blood cells (erythrocytosis) occurred in both mouse and primate models, and was associated with near-complete neutralization of VEGF corneal micropocket angiogenesis. High-grade inhibition of VEGF induced hepatic synthesis of erythropoietin (Epo, encoded by Epo) >40-fold through a HIF-1alpha-independent mechanism, in parallel with suppression of renal Epo mRNA. Studies using hepatocyte-specific deletion of the Vegfa gene and hepatocyte-endothelial cell cocultures indicated that blockade of VEGF induced hepatic Epo by interfering with homeostatic VEGFR2-dependent paracrine signaling involving interactions between hepatocytes and endothelial cells. These data indicate that VEGF is a previously unsuspected negative regulator of hepatic Epo synthesis and erythropoiesis and suggest that levels of Epo and erythrocytosis could represent noninvasive surrogate markers for stringent blockade of VEGF in vivo.


Assuntos
Eritropoetina/fisiologia , Fígado/fisiologia , Fator A de Crescimento do Endotélio Vascular/fisiologia , Animais , Hematócrito , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Camundongos Transgênicos , Modelos Animais , Policitemia/fisiopatologia , Receptores de Fatores de Crescimento do Endotélio Vascular/fisiologia , Vasos Retinianos/fisiologia
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