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1.
Nature ; 615(7952): 436-442, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36922608

RESUMO

The globally important carbon sink of intact, old-growth tropical humid forests is declining because of climate change, deforestation and degradation from fire and logging1-3. Recovering tropical secondary and degraded forests now cover about 10% of the tropical forest area4, but how much carbon they accumulate remains uncertain. Here we quantify the aboveground carbon (AGC) sink of recovering forests across three main continuous tropical humid regions: the Amazon, Borneo and Central Africa5,6. On the basis of satellite data products4,7, our analysis encompasses the heterogeneous spatial and temporal patterns of growth in degraded and secondary forests, influenced by key environmental and anthropogenic drivers. In the first 20 years of recovery, regrowth rates in Borneo were up to 45% and 58% higher than in Central Africa and the Amazon, respectively. This is due to variables such as temperature, water deficit and disturbance regimes. We find that regrowing degraded and secondary forests accumulated 107 Tg C year-1 (90-130 Tg C year-1) between 1984 and 2018, counterbalancing 26% (21-34%) of carbon emissions from humid tropical forest loss during the same period. Protecting old-growth forests is therefore a priority. Furthermore, we estimate that conserving recovering degraded and secondary forests can have a feasible future carbon sink potential of 53 Tg C year-1 (44-62 Tg C year-1) across the main tropical regions studied.


Assuntos
Sequestro de Carbono , Carbono , Conservação dos Recursos Naturais , Florestas , Umidade , Árvores , Clima Tropical , Carbono/metabolismo , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Árvores/metabolismo , Agricultura Florestal/estatística & dados numéricos , Imagens de Satélites , Temperatura , Floresta Úmida , Bornéu , África Central , Brasil
2.
Nature ; 621(7978): 318-323, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37612502

RESUMO

The Amazon forest carbon sink is declining, mainly as a result of land-use and climate change1-4. Here we investigate how changes in law enforcement of environmental protection policies may have affected the Amazonian carbon balance between 2010 and 2018 compared with 2019 and 2020, based on atmospheric CO2 vertical profiles5,6, deforestation7 and fire data8, as well as infraction notices related to illegal deforestation9. We estimate that Amazonia carbon emissions increased from a mean of 0.24 ± 0.08 PgC year-1 in 2010-2018 to 0.44 ± 0.10 PgC year-1 in 2019 and 0.52 ± 0.10 PgC year-1 in 2020 (± uncertainty). The observed increases in deforestation were 82% and 77% (94% accuracy) and burned area were 14% and 42% in 2019 and 2020 compared with the 2010-2018 mean, respectively. We find that the numbers of notifications of infractions against flora decreased by 30% and 54% and fines paid by 74% and 89% in 2019 and 2020, respectively. Carbon losses during 2019-2020 were comparable with those of the record warm El Niño (2015-2016) without an extreme drought event. Statistical tests show that the observed differences between the 2010-2018 mean and 2019-2020 are unlikely to have arisen by chance. The changes in the carbon budget of Amazonia during 2019-2020 were mainly because of western Amazonia becoming a carbon source. Our results indicate that a decline in law enforcement led to increases in deforestation, biomass burning and forest degradation, which increased carbon emissions and enhanced drying and warming of the Amazon forests.


Assuntos
Dióxido de Carbono , Sequestro de Carbono , Conservação dos Recursos Naturais , Política Ambiental , Aplicação da Lei , Floresta Úmida , Biomassa , Brasil , Dióxido de Carbono/análise , Dióxido de Carbono/metabolismo , Política Ambiental/legislação & jurisprudência , Atmosfera/química , Incêndios Florestais/estatística & dados numéricos , Conservação dos Recursos Naturais/estatística & dados numéricos , El Niño Oscilação Sul , Secas/estatística & dados numéricos
3.
Nature ; 608(7923): 558-562, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35948632

RESUMO

The productivity of rainforests growing on highly weathered tropical soils is expected to be limited by phosphorus availability1. Yet, controlled fertilization experiments have been unable to demonstrate a dominant role for phosphorus in controlling tropical forest net primary productivity. Recent syntheses have demonstrated that responses to nitrogen addition are as large as to phosphorus2, and adaptations to low phosphorus availability appear to enable net primary productivity to be maintained across major soil phosphorus gradients3. Thus, the extent to which phosphorus availability limits tropical forest productivity is highly uncertain. The majority of the Amazonia, however, is characterized by soils that are more depleted in phosphorus than those in which most tropical fertilization experiments have taken place2. Thus, we established a phosphorus, nitrogen and base cation addition experiment in an old growth Amazon rainforest, with a low soil phosphorus content that is representative of approximately 60% of the Amazon basin. Here we show that net primary productivity increased exclusively with phosphorus addition. After 2 years, strong responses were observed in fine root (+29%) and canopy productivity (+19%), but not stem growth. The direct evidence of phosphorus limitation of net primary productivity suggests that phosphorus availability may restrict Amazon forest responses to CO2 fertilization4, with major implications for future carbon sequestration and forest resilience to climate change.


Assuntos
Mudança Climática , Fósforo , Floresta Úmida , Solo , Árvores , Clima Tropical , Aclimatação , Dióxido de Carbono/metabolismo , Dióxido de Carbono/farmacologia , Sequestro de Carbono , Cátions/metabolismo , Cátions/farmacologia , Mudança Climática/estatística & dados numéricos , Modelos Biológicos , Nitrogênio/metabolismo , Nitrogênio/farmacologia , Fósforo/metabolismo , Fósforo/farmacologia , Solo/química , Árvores/efeitos dos fármacos , Árvores/metabolismo , Incerteza
4.
Nature ; 595(7867): 388-393, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34262208

RESUMO

Amazonia hosts the Earth's largest tropical forests and has been shown to be an important carbon sink over recent decades1-3. This carbon sink seems to be in decline, however, as a result of factors such as deforestation and climate change1-3. Here we investigate Amazonia's carbon budget and the main drivers responsible for its change into a carbon source. We performed 590 aircraft vertical profiling measurements of lower-tropospheric concentrations of carbon dioxide and carbon monoxide at four sites in Amazonia from 2010 to 20184. We find that total carbon emissions are greater in eastern Amazonia than in the western part, mostly as a result of spatial differences in carbon-monoxide-derived fire emissions. Southeastern Amazonia, in particular, acts as a net carbon source (total carbon flux minus fire emissions) to the atmosphere. Over the past 40 years, eastern Amazonia has been subjected to more deforestation, warming and moisture stress than the western part, especially during the dry season, with the southeast experiencing the strongest trends5-9. We explore the effect of climate change and deforestation trends on carbon emissions at our study sites, and find that the intensification of the dry season and an increase in deforestation seem to promote ecosystem stress, increase in fire occurrence, and higher carbon emissions in the eastern Amazon. This is in line with recent studies that indicate an increase in tree mortality and a reduction in photosynthesis as a result of climatic changes across Amazonia1,10.


Assuntos
Ciclo do Carbono , Sequestro de Carbono , Mudança Climática/estatística & dados numéricos , Conservação dos Recursos Naturais/estatística & dados numéricos , Florestas , Atmosfera/química , Dióxido de Carbono/análise , Monóxido de Carbono/análise , Atividades Humanas , Fotossíntese , Chuva , Estações do Ano , Temperatura
5.
FASEB J ; 38(17): e23892, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39230563

RESUMO

Mesenchymal stromal stem cells (MSCs) or skeletal stem cells (SSCs) play a major role in tissue repair due to their robust ability to differentiate into osteoblasts, chondrocytes, and adipocytes. Complex cell signaling cascades tightly regulate this differentiation. In osteogenic differentiation, Runt-related transcription factor 2 (RUNX2) and ALP activity are essential. Furthermore, during the latter stages of osteogenic differentiation, mineral formation mediated by the osteoblast occurs with the secretion of a collagenous extracellular matrix and calcium deposition. Activation of nuclear factor erythroid 2-related factor 2 (NRF2), an important transcription factor against oxidative stress, inhibits osteogenic differentiation and mineralization via modulation of RUNX2 function; however, the exact role of NRF2 in osteoblastogenesis remains unclear. Here, we demonstrate that NRF2 activation in human bone marrow-derived stromal cells (HBMSCs) suppressed osteogenic differentiation. NRF2 activation increased the expression of STRO-1 and KITLG (stem cell markers), indicating NRF2 protects HBMSCs stemness against osteogenic differentiation. In contrast, NRF2 activation enhanced mineralization, which is typically linked to osteogenic differentiation. We determined that these divergent results were due in part to the modulation of cellular calcium flux genes by NRF2 activation. The current findings demonstrate a dual role for NRF2 as a HBMSC maintenance factor as well as a central factor in mineralization, with implications therein for elucidation of bone formation and cellular Ca2+ kinetics, dystrophic calcification and, potentially, application in the modulation of bone formation.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais , Fator 2 Relacionado a NF-E2 , Osteoblastos , Osteogênese , Humanos , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/genética , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Osteogênese/fisiologia , Diferenciação Celular/fisiologia , Osteoblastos/metabolismo , Osteoblastos/citologia , Calcificação Fisiológica/fisiologia , Células Cultivadas , Células da Medula Óssea/metabolismo , Células da Medula Óssea/citologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/genética
6.
Arterioscler Thromb Vasc Biol ; 44(5): 1053-1064, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38482694

RESUMO

Zebrafish have become a powerful model of mammalian lipoprotein metabolism and lipid cell biology. Most key proteins involved in lipid metabolism, including cholesteryl ester transfer protein, are conserved in zebrafish. Consequently, zebrafish exhibit a human-like lipoprotein profile. Zebrafish with mutations in genes linked to human metabolic diseases often mimic the human phenotype. Zebrafish larvae develop rapidly and externally around the maternally deposited yolk. Recent work revealed that any disturbance of lipoprotein formation leads to the accumulation of cytoplasmic lipid droplets and an opaque yolk, providing a visible phenotype to investigate disturbances of the lipoprotein pathway, already leading to discoveries in MTTP (microsomal triglyceride transfer protein) and ApoB (apolipoprotein B). By 5 days of development, the digestive system is functional, making it possible to study fluorescently labeled lipid uptake in the transparent larvae. These and other approaches enabled the first in vivo description of the STAB (stabilin) receptors, showing lipoprotein uptake in endothelial cells. Various zebrafish models have been developed to mimic human diseases by mutating genes known to influence lipoproteins (eg, ldlra, apoC2). This review aims to discuss the most recent research in the zebrafish ApoB-containing lipoprotein and lipid metabolism field. We also summarize new insights into lipid processing within the yolk cell and how changes in lipid flux alter yolk opacity. This curious new finding, coupled with the development of several techniques, can be deployed to identify new players in lipoprotein research directly relevant to human disease.


Assuntos
Apolipoproteínas B , Modelos Animais de Doenças , Metabolismo dos Lipídeos , Peixe-Zebra , Peixe-Zebra/genética , Animais , Metabolismo dos Lipídeos/genética , Apolipoproteínas B/metabolismo , Apolipoproteínas B/genética , Humanos , Fenótipo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Mutação
7.
Proc Natl Acad Sci U S A ; 119(27): e2202310119, 2022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35759674

RESUMO

Human activities pose a major threat to tropical forest biodiversity and ecosystem services. Although the impacts of deforestation are well studied, multiple land-use and land-cover transitions (LULCTs) occur in tropical landscapes, and we do not know how LULCTs differ in their rates or impacts on key ecosystem components. Here, we quantified the impacts of 18 LULCTs on three ecosystem components (biodiversity, carbon, and soil), based on 18 variables collected from 310 sites in the Brazilian Amazon. Across all LULCTs, biodiversity was the most affected ecosystem component, followed by carbon stocks, but the magnitude of change differed widely among LULCTs and individual variables. Forest clearance for pasture was the most prevalent and high-impact transition, but we also identified other LULCTs with high impact but lower prevalence (e.g., forest to agriculture). Our study demonstrates the importance of considering multiple ecosystem components and LULCTs to understand the consequences of human activities in tropical landscapes.


Assuntos
Efeitos Antropogênicos , Biodiversidade , Conservação dos Recursos Naturais , Floresta Úmida , Agricultura , Brasil , Carbono , Humanos
8.
Breast Cancer Res ; 26(1): 126, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198859

RESUMO

BACKGROUND AND OBJECTIVE: Aurora kinase A (AURKA) is reported to be overexpressed in breast cancer. In addition to its role in regulating cell cycle and mitosis, studies have reported AURKA involvements in oncogenic signaling in suppressing BRCA1 and BRCA2. We aimed to characterize AURKA protein and mRNA expression in a breast cancer cohort of the young, investigating its relation to clinico-pathologic features and survival, and exploring age-related AURKA-associated biological processes. METHODS: Aurora kinase A immunohistochemical staining was performed on tissue microarrays of primary tumors from an in-house breast cancer cohort (n = 355) with information on clinico-pathologic data, molecular markers, and long and complete follow-up. A subset of the in-house cohort (n = 127) was studied by the NanoString Breast Cancer 360 expression panel for exploration of mRNA expression. METABRIC cohorts < 50 years at breast cancer diagnosis (n = 368) were investigated for differentially expressed genes and enriched gene sets in AURKA mRNA high tumors stratified by age. Differentially expressed genes and gene sets were investigated using network analyses and g:Profiler. RESULTS: High Aurora kinase A protein expression associated with aggressive clinico-pathologic features, a basal-like subtype, and high risk of recurrence score. These patterns were confirmed using mRNA data. High AURKA gene expression demonstrated independent prognostic value when adjusted for traditional clinico-pathologic features and molecular subtypes. Notably, high AURKA expression significantly associated with reduced disease-specific survival within patients below 50 years, also within the luminal A subtype. Tumors of high AURKA expression showed gene expression patterns reflecting increased DNA damage activation and higher BRCAness score. CONCLUSIONS: Our findings indicate higher AURKA expression in young breast cancer, and associations between high Aurora-A/AURKA and aggressive tumor features, including higher tumor cell proliferation, and shorter survival, in the young. Our findings point to AURKA as a marker for increased DNA damage and DNA repair deficiency and suggest AURKA as a biomarker of clinical relevance in young breast cancer.


Assuntos
Aurora Quinase A , Biomarcadores Tumorais , Neoplasias da Mama , Humanos , Aurora Quinase A/genética , Aurora Quinase A/metabolismo , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/metabolismo , Pessoa de Meia-Idade , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Adulto , Fatores Etários , Prognóstico , Regulação Neoplásica da Expressão Gênica , Perfilação da Expressão Gênica , Estadiamento de Neoplasias
9.
Int J Cancer ; 154(11): 2014-2024, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38319154

RESUMO

Breast cancer in young (<40 years) is associated with a higher frequency of aggressive tumor types and poor prognosis. It remains unclear if there is an underlying age-related biology that contributes to the unfavorable outcome. We aim to investigate the relationship between age and breast cancer biology, with emphasis on proliferation. Clinico-pathologic information, immunohistochemical markers and follow-up data were obtained for all patients aged <50 (Bergen cohort-1; n = 355, not part of a breast screening program) and compared to previously obtained information on patients aged 50 to 69 years (Bergen cohort-2; n = 540), who participated in the Norwegian Breast Cancer Screening Program. Young breast cancer patients presented more aggressive tumor features such as hormone receptor negativity, HER2 positivity, lymph-node metastasis, the HER2-enriched and triple-negative subtypes and shorter survival. Age <40 was significantly associated with higher proliferation (by Ki67). Ki67 showed weaker prognostic value in young patients. We point to aggressive phenotypes and increased tumor cell proliferation in breast cancer of the young. Hence, tumors of young breast cancer patients may present unique biological features, also when accounting for screen/interval differences, that may open for new clinical opportunities, stratifying treatment by age.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/patologia , Antígeno Ki-67 , Receptor ErbB-2/genética , Prognóstico , Proliferação de Células , Receptores de Progesterona , Biomarcadores Tumorais/genética
10.
Am J Transplant ; 24(3): 350-361, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37931753

RESUMO

The XVIth Banff Meeting for Allograft Pathology was held in Banff, Alberta, Canada, from September 19 to 23, 2022, as a joint meeting with the Canadian Society of Transplantation. In addition to a key focus on the impact of microvascular inflammation and biopsy-based transcript analysis on the Banff Classification, further sessions were devoted to other aspects of kidney transplant pathology, in particular T cell-mediated rejection, activity and chronicity indices, digital pathology, xenotransplantation, clinical trials, and surrogate endpoints. Although the output of these sessions has not led to any changes in the classification, the key role of Banff Working Groups in phrasing unanswered questions, and coordinating and disseminating results of investigations addressing these unanswered questions was emphasized. This paper summarizes the key Banff Meeting 2022 sessions not covered in the Banff Kidney Meeting 2022 Report paper and also provides an update on other Banff Working Group activities relevant to kidney allografts.


Assuntos
Transplante de Rim , Canadá , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Rim/patologia , Aloenxertos
11.
Am J Transplant ; 24(6): 905-917, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38461883

RESUMO

The Banff Working Group on Liver Allograft Pathology met in September 2022. Participants included hepatologists, surgeons, pathologists, immunologists, and histocompatibility specialists. Presentations and discussions focused on the evaluation of long-term allograft health, including noninvasive and tissue monitoring, immunosuppression optimization, and long-term structural changes. Potential revision of the rejection classification scheme to better accommodate and communicate late T cell-mediated rejection patterns and related structural changes, such as nodular regenerative hyperplasia, were discussed. Improved stratification of long-term maintenance immunosuppression to match the heterogeneity of patient settings will be central to improving long-term patient survival. Such personalized therapeutics are in turn contingent on a better understanding and monitoring of allograft status within a rational decision-making approach, likely to be facilitated in implementation with emerging decision-support tools. Proposed revisions to rejection classification emerging from the meeting include the incorporation of interface hepatitis and fibrosis staging. These will be opened to online testing, modified accordingly, and subject to consensus discussion leading up to the next Banff conference.


Assuntos
Rejeição de Enxerto , Transplante de Fígado , Humanos , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto , Aloenxertos
12.
Ann Oncol ; 35(8): 718-727, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38729566

RESUMO

BACKGROUND: In MONARCH 2, the addition of abemaciclib to fulvestrant significantly improved both progression-free survival (PFS) and overall survival (OS) in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) with disease progression on prior endocrine therapy. In MONARCH 3, the addition of abemaciclib to a nonsteroidal aromatase inhibitor (NSAI) as initial therapy for HR+, HER2- ABC significantly improved PFS. Here, we present the prespecified final OS results for MONARCH 3. PATIENTS AND METHODS: MONARCH 3 is a randomized, double-blind, phase III study of abemaciclib plus NSAI (anastrozole or letrozole) versus placebo plus NSAI in postmenopausal women with HR+, HER2- ABC without prior systemic therapy in the advanced setting. The primary objective was investigator-assessed PFS; OS was a gated secondary endpoint, and chemotherapy-free survival was an exploratory endpoint. RESULTS: A total of 493 women were randomized 2 : 1 to receive abemaciclib plus NSAI (n = 328) or placebo plus NSAI (n = 165). After a median follow-up of 8.1 years, there were 198 OS events (60.4%) in the abemaciclib arm and 116 (70.3%) in the placebo arm (hazard ratio, 0.804; 95% confidence interval 0.637-1.015; P = 0.0664, non-significant). Median OS was 66.8 versus 53.7 months for abemaciclib versus placebo. In the subgroup with visceral disease, there were 113 OS events (65.3%) in the abemaciclib arm and 65 (72.2%) in the placebo arm (hazard ratio, 0.758; 95% confidence interval 0.558-1.030; P = 0.0757, non-significant). Median OS was 63.7 months versus 48.8 months for abemaciclib versus placebo. The previously demonstrated PFS benefit was sustained, and chemotherapy-free survival numerically improved with the addition of abemaciclib. No new safety signals were observed. CONCLUSIONS: Abemaciclib combined with an NSAI resulted in clinically meaningful improvement in median OS (intent-to-treat population: 13.1 months; subgroup with visceral disease: 14.9 months) in patients with HR+ HER2- ABC; however, statistical significance was not reached.


Assuntos
Aminopiridinas , Protocolos de Quimioterapia Combinada Antineoplásica , Inibidores da Aromatase , Benzimidazóis , Neoplasias da Mama , Letrozol , Receptor ErbB-2 , Receptores de Estrogênio , Receptores de Progesterona , Humanos , Feminino , Aminopiridinas/administração & dosagem , Aminopiridinas/uso terapêutico , Benzimidazóis/administração & dosagem , Benzimidazóis/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Receptor ErbB-2/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Método Duplo-Cego , Letrozol/administração & dosagem , Letrozol/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Inibidores da Aromatase/administração & dosagem , Pessoa de Meia-Idade , Idoso , Receptores de Progesterona/metabolismo , Receptores de Estrogênio/metabolismo , Anastrozol/uso terapêutico , Anastrozol/administração & dosagem , Adulto , Idoso de 80 Anos ou mais , Intervalo Livre de Progressão
13.
J Med Virol ; 96(3): e29489, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38402605

RESUMO

Human astrovirus (HAstV) is a nonenveloped RNA virus and has been implicated in acute gastroenteritis among children and elderly. However, there exists a substantial dearth of information on HAstV strains circulating in Nigeria. Viral-like particles were purified from archived 254 stool samples of children with acute flaccid paralysis between January and December 2020 from five states in Nigeria, using the NetoVIR protocol. Extracted viral RNA and DNA were subjected to a reverse transcription step and subsequent random polymerase chain reaction amplification. Library preparation and Illumina sequencing were performed. Using the virome paired-end reads pipeline, raw reads were processed into genomic contigs. Phylogenetic and pairwise identity analysis of the recovered HAstV genomes was performed. Six near-complete genome sequences of HAstV were identified and classified as HAstV4 (n = 1), HAstV5 (n = 1), HAstV8 (n = 1), and MLB-3 (n = 3). The HAstV5 belonged to a yet unclassified sublineage, which we tentatively named HAstV-5d. Phylogenetic analysis of open reading frames 1a, 1b, and 2 suggested recombination events inside the MAstV1 species. Furthermore, phylogenetic analysis implied a geographic linkage between the HAstV5 strain from this study with two strains from Cameroon across all the genomic regions. We report for the first time the circulation of HAstV genotypes 4, 8, and MLB-3 in Nigeria and present data suggestive for the existence of a new sublineage of HAstV5. To further understand the burden, diversity, and evolution of HAstV, increased research interest as well as robust HAstV surveillance in Nigeria is essential.


Assuntos
Infecções por Astroviridae , Mamastrovirus , Criança , Humanos , Idoso , Mamastrovirus/genética , Filogenia , Nigéria/epidemiologia , Infecções por Astroviridae/epidemiologia , Fezes , Genótipo
14.
J Inherit Metab Dis ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591231

RESUMO

Coenzyme A (CoA) is an essential cofactor required for over a hundred metabolic reactions in the human body. This cofactor is synthesized de novo in our cells from vitamin B5, also known as pantothenic acid, a water-soluble vitamin abundantly present in vegetables and animal-based foods. Neurodegenerative disorders, cancer, and infectious diseases have been linked to defects in de novo CoA biosynthesis or reduced levels of this coenzyme. There is now accumulating evidence that CoA limitation is a critical pathomechanism in cardiac dysfunction too. In the current review, we will summarize our current knowledge on CoA and heart failure, with emphasis on two primary cardiomyopathies, phosphopantothenoylcysteine synthetase and phosphopantothenoylcysteine decarboxylase deficiency disorders biochemically characterized by a decreased level of CoA in patients' samples. Hence, we will discuss the potential benefits of CoA restoration in these diseases and, more generally, in heart failure, by vitamin B5 and its derivatives pantethine and 4'-phosphopantetheine.

15.
BMC Psychiatry ; 24(1): 92, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302998

RESUMO

BACKGROUND: Online therapies have been shown to be effective in improving students' mental health. They are cost-effective and therefore have particular advantages in low-income countries like Zambia where mental health resources are limited. This study aimed to explore the perceived impact of the COVID-19 pandemic and the feasibility of implementing an Internet-Based Cognitive Behavioural Therapy (iCBT) intervention ('moodgym') to improve resilience in vulnerable Zambian students. METHODS: The study was a qualitative interview study. Participants identifying as having symptoms of low mood and completing a baseline, online survey (n = 620) had the option to volunteer for a semi-structured interview to explore views about their experience of the pandemic and the acceptability and perceived benefits and limitations of using moodgym. RESULTS: A total of 50 students (n = 24 female, n = 26 male) participated in the study. One theme with 4 sub-themes, captured the severe emotional and social impact of the COVID-19 pandemic. A second, very strong theme, with 5 sub-themes, reflected the considerable negative effects of the pandemic on the students' educational experience. This included the challenges of online learning. The third theme, with three subthemes, captured the benefits and acceptability of moodgym, particularly in terms of understanding the relationship between thoughts and feelings and improving academic performance. The fourth theme described the technical difficulties experienced by students in attempting to use moodgym. CONCLUSION: COVID-19 caused fear and impacted wellbeing in vulnerable students and severely impaired the quality of students' educational experience. The findings suggest that moodgym might be a valuable support to students in a low-income country.


Assuntos
COVID-19 , Terapia Cognitivo-Comportamental , Humanos , Masculino , Feminino , Pandemias , Pesquisa Qualitativa , Estudantes , Internet
16.
Appetite ; 200: 107571, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38925207

RESUMO

The use of mobile applications to assist with food decision making has increased significantly. Although food scanner applications provide nutritional information to consumers in the marketplace, little is known about their effects on users' intentions and behavior. This research investigates whether a mobile food scanner app can influence consumers toward healthier food choices. Four studies tested whether information displayed through a food scanner app (as opposed to no information or front-of-packaging label information) influenced purchase intentions for food products (Studies 1-3) or led consumers to make healthier food choices (Study 4). Application-provided information enhanced hypothetical choice and purchase intentions of healthy products in comparison no information, but it did not influence real behavior when participants made choices in an experimental supermarket. Information provided through a food scanner app was systematically outperformed by front-of-packaging label information.


Assuntos
Comportamento de Escolha , Comportamento do Consumidor , Dieta Saudável , Rotulagem de Alimentos , Preferências Alimentares , Aplicativos Móveis , Humanos , Preferências Alimentares/psicologia , Masculino , Feminino , Adulto , Rotulagem de Alimentos/métodos , Dieta Saudável/psicologia , Dieta Saudável/métodos , Adulto Jovem , Intenção , Adolescente , Pessoa de Meia-Idade , Supermercados
17.
Proc Natl Acad Sci U S A ; 118(7)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33558246

RESUMO

In the Amazon rainforest, land use following deforestation is diverse and dynamic. Mounting evidence indicates that the climatic impacts of forest loss can also vary considerably, depending on specific features of the affected areas. The size of the deforested patches, for instance, was shown to modulate the characteristics of local climatic impacts. Nonetheless, the influence of different types of land use and management strategies on the magnitude of local climatic changes remains uncertain. Here, we evaluated the impacts of large-scale commodity farming and rural settlements on surface temperature, rainfall patterns, and energy fluxes. Our results reveal that changes in land-atmosphere coupling are induced not only by deforestation size but also, by land use type and management patterns inside the deforested areas. We provide evidence that, in comparison with rural settlements, deforestation caused by large-scale commodity agriculture is more likely to reduce convective rainfall and increase land surface temperature. We demonstrate that these differences are mainly caused by a more intensive management of the land, resulting in significantly lower vegetation cover throughout the year, which reduces latent heat flux. Our findings indicate an urgent need for alternative agricultural practices, as well as forest restoration, for maintaining ecosystem processes and mitigating change in the local climates across the Amazon basin.


Assuntos
Agricultura/estatística & dados numéricos , Processos Climáticos , Conservação dos Recursos Naturais/estatística & dados numéricos , Ecossistema
18.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34282005

RESUMO

With humanity facing an unprecedented climate crisis, the conservation of tropical forests has never been so important - their vast terrestrial carbon stocks can be turned into emissions by climatic and human disturbances. However, the duration of these effects is poorly understood, and it is unclear whether impacts are amplified in forests with a history of previous human disturbance. Here, we focus on the Amazonian epicenter of the 2015-16 El Niño, a region that encompasses 1.2% of the Brazilian Amazon. We quantify, at high temporal resolution, the impacts of an extreme El Niño (EN) drought and extensive forest fires on plant mortality and carbon loss in undisturbed and human-modified forests. Mortality remained higher than pre-El Niño levels for 36 mo in EN-drought-affected forests and for 30 mo in EN-fire-affected forests. In EN-fire-affected forests, human disturbance significantly increased plant mortality. Our investigation of the ecological and physiological predictors of tree mortality showed that trees with lower wood density, bark thickness and leaf nitrogen content, as well as those that experienced greater fire intensity, were more vulnerable. Across the region, the 2015-16 El Niño led to the death of an estimated 2.5 ± 0.3 billion stems, resulting in emissions of 495 ± 94 Tg CO2 Three years after the El Niño, plant growth and recruitment had offset only 37% of emissions. Our results show that limiting forest disturbance will not only help maintain carbon stocks, but will also maximize the resistance of Amazonian forests if fires do occur.


Assuntos
Ciclo do Carbono , Secas , El Niño Oscilação Sul , Agricultura Florestal/estatística & dados numéricos , Fenômenos Fisiológicos Vegetais , Árvores/crescimento & desenvolvimento , Incêndios Florestais , Brasil , Florestas , Humanos
19.
Scand J Caring Sci ; 38(2): 451-460, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38433372

RESUMO

BACKGROUND: Patients receiving a brain cancer diagnosis may face cognitive decline and a poor prognosis. In addition, they suffer from a high symptom burden in a complex cancer pathway. The aim of this study was to investigate the early hospital experiences of brain tumour patients during the diagnostic and surgical treatment phase. METHODS: A descriptive longitudinal single-case study design was used, and data were analysed via systematic text condensation. RESULTS: The patients' experiences of being diagnosed with and treated for brain cancer were interpreted in terms of the central theme: a fast transition into an unknown journey. This theme consisted of the following subthemes: emotionally overwhelmed, putting life on hold and an unfamiliar dependency. CONCLUSIONS: Patients diagnosed with brain cancer struggle with overwhelming emotions due to this sudden life-threatening diagnosis, their fear of brain surgery and their progressing dependence. Patients did not voice their feelings, fears or needs, so these may easily be overlooked and unmet. A proactive and continuous care approach throughout the diagnostic phase is needed to support these patients.


Assuntos
Neoplasias Encefálicas , Humanos , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/psicologia , Neoplasias Encefálicas/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Longitudinais , Adulto
20.
Trop Anim Health Prod ; 56(4): 152, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722369

RESUMO

Supplementing livestock grazing communal rangelands with leaf-meals from Acacia trees, which are currently considered as problematic invasive alien plants globally, may be a sustainable way of exploiting their desirable nutritional and anthelmintic properties. The current study evaluated worm burdens and growth performance of lambs grazing low-quality communal rangelands supplemented with leaf-meals prepared from the invasive alien plant species; Acacia mearnsii or A. dealbata. Forty, three-month-old ewe lambs weighing an average of 18.9 ± 0.60 kg were randomly allocated to four supplementary diets: (1) rangeland hay only (control), (2) commercial protein supplement plus rangeland hay, (3) A. mearnsii leaf-meal plus rangeland hay and (4) A. dealbata leaf-meal plus rangeland hay. All the supplementary diets were formulated to meet the lambs' minimum maintenance requirements for protein. All the lambs were grazed on communal rangelands daily from 0800 to 1400 after which they were penned to allow them access to their respective supplementary diets until 08:00 the following morning. The respective supplementary diets were offered at the rate of 400 g ewe- 1 day- 1 for 60 days. Lambs fed the commercial protein supplement had the highest dry matter intake followed by those fed the Acacia leaf-meals and the control diet, respectively (P ≤ 0.05). Relative to the other supplementary diets, lambs fed the commercial protein supplement and A. dealbata leaf-meal had higher (P ≤ 0.05) final body weight and average daily gains. Dietary supplementation did not affect lamb faecal worm egg counts over the study period (P > 0.05). There was no association between supplementary diets and lamb FAMACHA© scores (P > 0.05). It was concluded that supplementation of Acacia dealbata versus Acacia mearnsii has the potential to emulate commercial protein in maintaining growth performance of lambs grazing communal rangelands in the dry season.


Assuntos
Acacia , Ração Animal , Dieta , Suplementos Nutricionais , Folhas de Planta , Animais , Ração Animal/análise , Folhas de Planta/química , Suplementos Nutricionais/análise , Feminino , África do Sul , Dieta/veterinária , Carneiro Doméstico/crescimento & desenvolvimento , Carneiro Doméstico/fisiologia , Doenças dos Ovinos/prevenção & controle , Doenças dos Ovinos/parasitologia , Ovinos/crescimento & desenvolvimento , Ovinos/fisiologia , Fezes , Distribuição Aleatória , Contagem de Ovos de Parasitas/veterinária , Fenômenos Fisiológicos da Nutrição Animal
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