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1.
Nature ; 596(7873): 536-542, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34433947

RESUMO

Tropical forests store 40-50 per cent of terrestrial vegetation carbon1. However, spatial variations in aboveground live tree biomass carbon (AGC) stocks remain poorly understood, in particular in tropical montane forests2. Owing to climatic and soil changes with increasing elevation3, AGC stocks are lower in tropical montane forests compared with lowland forests2. Here we assemble and analyse a dataset of structurally intact old-growth forests (AfriMont) spanning 44 montane sites in 12 African countries. We find that montane sites in the AfriMont plot network have a mean AGC stock of 149.4 megagrams of carbon per hectare (95% confidence interval 137.1-164.2), which is comparable to lowland forests in the African Tropical Rainforest Observation Network4 and about 70 per cent and 32 per cent higher than averages from plot networks in montane2,5,6 and lowland7 forests in the Neotropics, respectively. Notably, our results are two-thirds higher than the Intergovernmental Panel on Climate Change default values for these forests in Africa8. We find that the low stem density and high abundance of large trees of African lowland forests4 is mirrored in the montane forests sampled. This carbon store is endangered: we estimate that 0.8 million hectares of old-growth African montane forest have been lost since 2000. We provide country-specific montane forest AGC stock estimates modelled from our plot network to help to guide forest conservation and reforestation interventions. Our findings highlight the need for conserving these biodiverse9,10 and carbon-rich ecosystems.


Assuntos
Atitude , Sequestro de Carbono , Carbono/análise , Floresta Úmida , Árvores/metabolismo , Clima Tropical , África , Biomassa , Mudança Climática , Conservação dos Recursos Naturais , Conjuntos de Dados como Assunto , Mapeamento Geográfico
3.
Nature ; 585(7826): 551-556, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32908312

RESUMO

Increased efforts are required to prevent further losses to terrestrial biodiversity and the ecosystem services that it  provides1,2. Ambitious targets have been proposed, such as reversing the declining trends in biodiversity3; however, just feeding the growing human population will make this a challenge4. Here we use an ensemble of land-use and biodiversity models to assess whether-and how-humanity can reverse the declines in terrestrial biodiversity caused by habitat conversion, which is a major threat to biodiversity5. We show that immediate efforts, consistent with the broader sustainability agenda but of unprecedented ambition and coordination, could enable the provision of food for the growing human population while reversing the global terrestrial biodiversity trends caused by habitat conversion. If we decide to increase the extent of land under conservation management, restore degraded land and generalize landscape-level conservation planning, biodiversity trends from habitat conversion could become positive by the mid-twenty-first century on average across models (confidence interval, 2042-2061), but this was not the case for all models. Food prices could increase and, on average across models, almost half (confidence interval, 34-50%) of the future biodiversity losses could not be avoided. However, additionally tackling the drivers of land-use change could avoid conflict with affordable food provision and reduces the environmental effects of the food-provision system. Through further sustainable intensification and trade, reduced food waste and more plant-based human diets, more than two thirds of future biodiversity losses are avoided and the biodiversity trends from habitat conversion are reversed by 2050 for almost all of the models. Although limiting further loss will remain challenging in several biodiversity-rich regions, and other threats-such as climate change-must be addressed to truly reverse the declines in biodiversity, our results show that ambitious conservation efforts and food system transformation are central to an effective post-2020 biodiversity strategy.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Política Ambiental/tendências , Atividades Humanas/tendências , Dieta , Dieta Vegetariana/tendências , Abastecimento de Alimentos , Humanos , Desenvolvimento Sustentável/tendências
4.
N Engl J Med ; 387(17): 1557-1568, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36094839

RESUMO

BACKGROUND: In a pilot study involving patients with cutaneous squamous-cell carcinoma, a high percentage of patients had a pathological complete response with the use of two doses of neoadjuvant cemiplimab before surgery. Data from a phase 2 study are needed to confirm these findings. METHODS: We conducted a phase 2, confirmatory, multicenter, nonrandomized study to evaluate cemiplimab as neoadjuvant therapy in patients with resectable stage II, III, or IV (M0) cutaneous squamous-cell carcinoma. Patients received cemiplimab, administered at a dose of 350 mg every 3 weeks for up to four doses, before undergoing surgery with curative intent. The primary end point was a pathological complete response (the absence of viable tumor cells in the surgical specimen) on independent review at a central laboratory, with a null hypothesis that a pathological complete response would be observed in 25% of patients. Key secondary end points included a pathological major response (the presence of viable tumor cells that constitute ≤10% of the surgical specimen) on independent review, a pathological complete response and a pathological major response on investigator assessment at a local laboratory, an objective response on imaging, and adverse events. RESULTS: A total of 79 patients were enrolled and received neoadjuvant cemiplimab. On independent review, a pathological complete response was observed in 40 patients (51%; 95% confidence interval [CI], 39 to 62) and a pathological major response in 10 patients (13%; 95% CI, 6 to 22). These results were consistent with the pathological responses determined on investigator assessment. An objective response on imaging was observed in 54 patients (68%; 95% CI, 57 to 78). Adverse events of any grade that occurred during the study period, regardless of whether they were attributed to the study treatment, were observed in 69 patients (87%). Grade 3 or higher adverse events that occurred during the study period were observed in 14 patients (18%). CONCLUSIONS: Neoadjuvant therapy with cemiplimab was associated with a pathological complete response in a high percentage of patients with resectable cutaneous squamous-cell carcinoma. (Funded by Regeneron Pharmaceuticals and Sanofi; ClinicalTrials.gov number, NCT04154943.).


Assuntos
Carcinoma de Células Escamosas , Terapia Neoadjuvante , Neoplasias Cutâneas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/patologia , Estadiamento de Neoplasias , Projetos Piloto , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Indução de Remissão , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico
5.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38152979

RESUMO

The identification and characterization of essential genes are central to our understanding of the core biological functions in eukaryotic organisms, and has important implications for the treatment of diseases caused by, for example, cancers and pathogens. Given the major constraints in testing the functions of genes of many organisms in the laboratory, due to the absence of in vitro cultures and/or gene perturbation assays for most metazoan species, there has been a need to develop in silico tools for the accurate prediction or inference of essential genes to underpin systems biological investigations. Major advances in machine learning approaches provide unprecedented opportunities to overcome these limitations and accelerate the discovery of essential genes on a genome-wide scale. Here, we developed and evaluated a large language model- and graph neural network (LLM-GNN)-based approach, called 'Bingo', to predict essential protein-coding genes in the metazoan model organisms Caenorhabditis elegans and Drosophila melanogaster as well as in Mus musculus and Homo sapiens (a HepG2 cell line) by integrating LLM and GNNs with adversarial training. Bingo predicts essential genes under two 'zero-shot' scenarios with transfer learning, showing promise to compensate for a lack of high-quality genomic and proteomic data for non-model organisms. In addition, the attention mechanisms and GNNExplainer were employed to manifest the functional sites and structural domain with most contribution to essentiality. In conclusion, Bingo provides the prospect of being able to accurately infer the essential genes of little- or under-studied organisms of interest, and provides a biological explanation for gene essentiality.


Assuntos
Proteínas de Drosophila , Genes Essenciais , Camundongos , Animais , Proteômica , Drosophila melanogaster/genética , Fluxo de Trabalho , Redes Neurais de Computação , Proteínas/genética , Proteínas dos Microfilamentos/genética , Proteínas de Drosophila/genética
6.
Nat Chem Biol ; 19(7): 911-920, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37188959

RESUMO

The incorporation of the nonstandard amino acid para-nitro-L-phenylalanine (pN-Phe) within proteins has been used for diverse applications, including the termination of immune self-tolerance. However, the requirement for the provision of chemically synthesized pN-Phe to cells limits the contexts where this technology can be harnessed. Here we report the construction of a live bacterial producer of synthetic nitrated proteins by coupling metabolic engineering and genetic code expansion. We achieved the biosynthesis of pN-Phe in Escherichia coli by creating a pathway that features a previously uncharacterized nonheme diiron N-monooxygenase, which resulted in pN-Phe titers of 820 ± 130 µM after optimization. After we identified an orthogonal translation system that exhibited selectivity toward pN-Phe rather than a precursor metabolite, we constructed a single strain that incorporated biosynthesized pN-Phe within a specific site of a reporter protein. Overall, our study has created a foundational technology platform for distributed and autonomous production of nitrated proteins.


Assuntos
Proteínas de Escherichia coli , Nitratos , Nitratos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fenilalanina/química , Proteínas de Escherichia coli/metabolismo , Aminoácidos/metabolismo
7.
Cancer Immunol Immunother ; 73(5): 85, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38554185

RESUMO

TGF-ß1 and TGF-ßR1 play important roles in immune and inflammatory responses. Genetic variants of TGF-ß1 rs1800470 and TGF-ßR1 rs334348 have emerged as potentially prognostic biomarkers for HPV-related head and neck cancer, while their prognostic effect on survival of smoking-related head and neck cancer remains unknown. This study included 1403 patients with smoking-related head and neck cancer, and all these patients were genotyped for TGF-ß1 rs1800470 and TGF-ßR1 rs334348. Both univariate and multivariate analyses were performed to evaluate associations between the two functional genetic variants in microRNA binding sites of TGF-ß1 and TGF-ßR1 and survivals. Patients with TGF-ß1 rs1800470 CT or CC genotype had 30-35% risk reductions for OS, DSS, and DFS compared to patients with TT genotype among overall patients, ever smokers, and patients administered chemoradiation. Furthermore, patients with TGF-ßR1 rs334348 GA or GG genotype had significant 50-60% risk reductions for OS, DSS, and DFS compared to patients with AA genotype among overall patients and patients administered chemoradiation; among ever smokers, the risk reductions even reached 60-70%. The TCGA dataset was used for validation. These findings suggest that TGF-ß1 rs1800470 and TGF-ßR1 rs334348 significantly affect survival outcomes in patients with smoking-related head and neck cancer, especially in the subgroups of ever smokers and patients treated with chemoradiation. These genetic variants may serve as prognostic indicators for patients with smoking-related head and neck cancer and could play a role in advancing the field of personalized chemoradiation, thereby improving patient survival and quality of life.


Assuntos
Neoplasias de Cabeça e Pescoço , MicroRNAs , Humanos , MicroRNAs/genética , Fator de Crescimento Transformador beta1/genética , Qualidade de Vida , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/terapia , Fumar/efeitos adversos
8.
BMC Plant Biol ; 24(1): 717, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39069632

RESUMO

BACKGROUND: Sclerotinia spp. are generalist fungal pathogens, infecting over 700 plant hosts worldwide, including major crops. While host resistance is the most sustainable and cost-effective method for disease management, complete resistance to Sclerotinia diseases is rare. We recently identified soft basal stem as a potential susceptibility factor to Sclerotinia minor infection in lettuce (Lactuca sativa) under greenhouse conditions. RESULTS: Analysis of stem and root cell wall composition in five L. sativa and one L. serriola accessions with varying growth habits and S. minor resistance levels revealed strong association between hemicellulose constituents, lignin polymers, disease phenotypes, and basal stem mechanical strength. Accessions resistant to basal stem degradation consistently exhibited higher levels of syringyl, guaiacyl, and xylose, but lower levels of fucose in stems. These findings suggest that stem cell wall polymers recalcitrant to breakdown by lignocellulolytic enzymes may contribute to stem strength-mediated resistance against S. minor. CONCLUSIONS: The lignin content, particularly guaiacyl and syringyl, along with xylose could potentially serve as biomarkers for identifying more resistant lettuce accessions and breeding lines. Basal stem degradation by S. minor was influenced by localized microenvironment conditions around the stem base of the plants.


Assuntos
Ascomicetos , Parede Celular , Resistência à Doença , Lactuca , Lignina , Doenças das Plantas , Caules de Planta , Caules de Planta/microbiologia , Caules de Planta/metabolismo , Parede Celular/metabolismo , Lactuca/microbiologia , Lactuca/metabolismo , Ascomicetos/fisiologia , Lignina/metabolismo , Doenças das Plantas/microbiologia , Polissacarídeos/metabolismo , Microambiente Celular , Raízes de Plantas/microbiologia , Raízes de Plantas/metabolismo
9.
Proc Biol Sci ; 291(2020): 20232340, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38593845

RESUMO

Studies of adaptive radiations have played a central role in our understanding of reproductive isolation. Yet the focus has been on human-biased visual and auditory signals, leaving gaps in our knowledge of other modalities. To date, studies on chemical signals in adaptive radiations have focused on systems with multimodal signalling, making it difficult to isolate the role chemicals play in reproductive isolation. In this study we examine the use of chemical signals in the species recognition and adaptive radiation of Hawaiian Tetragnatha spiders by focusing on entire communities of co-occurring species, and conducting behavioural assays in conjunction with chemical analysis of their silks using gas chromatography-mass spectrometry. Male spiders significantly preferred the silk extracts of conspecific mates over those of sympatric heterospecifics. The compounds found in the silk extracts, long chain alkyl methyl ethers, were remarkably species-specific in the combination and quantity. The differences in the profile were greatest between co-occurring species and between closely related sibling species. Lastly, there were significant differences in the chemical profile between two populations of a particular species. These findings provide key insights into the role chemical signals play in the attainment and maintenance of reproductive barriers between closely related co-occurring species.


Assuntos
Aranhas , Animais , Humanos , Masculino , Havaí , Especificidade da Espécie , Isolamento Reprodutivo , Seda
10.
Liver Transpl ; 30(4): 367-375, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37639285

RESUMO

The exception point system for liver allocation in the United States allows for additional waitlist priority for candidates where the Model for End-Stage Liver Disease or Pediatric End-stage Liver Disease does not effectively represent their urgency or need for a transplant. In May 2019, the review process for liver exception cases transitioned from 11 Regional Review Boards (RRBs) to 1 National Liver Review Board (NLRB), intended to increase consistency nationwide, improve efficiency, and balance transplant access for candidates with and without exception scores. This report provides a review of liver exception request and review practices, waitlist outcomes, and transplant activity in the first 2 years after implementation of the NLRB and acuity circle-based distribution in the United States. We compared initial and extension exception request forms submitted from May 13, 2017 to May 13, 2019 (prepolicy or RRB era) to the period from February 4, 2020 to February 3, 2022 (postpolicy or NLRB era). During this time, the NLRB reviewed 10,083 initial exception requests and 12,686 extension requests. Notable postpolicy highlights include (1) an increase in the proportion of initial and extension requests that were automatically approved instead of manually reviewed; (2) a decrease in the overall approval rates of initial exception requests (87.8% for adult HCC, 64.3% for adult other diagnoses, and 71.5% for pediatric); and (3) reduction in the time from exception request submission to adjudication to a median of 3.73 days. The proportions of waitlist registration and deceased donor liver transplants for patients with exception scores decreased, and waitlist outcomes between patients with and without exception scores are now comparable. Implementation of the NLRB improved efficiency, reduced case workloads, and standardized criteria for exception cases, with similar waitlist outcomes between patients with and without exception scores and improved equity in terms of access to liver transplants.


Assuntos
Carcinoma Hepatocelular , Doença Hepática Terminal , Neoplasias Hepáticas , Transplante de Fígado , Obtenção de Tecidos e Órgãos , Adulto , Humanos , Criança , Estados Unidos , Carcinoma Hepatocelular/diagnóstico , Doença Hepática Terminal/cirurgia , Neoplasias Hepáticas/diagnóstico , Transplante de Fígado/efeitos adversos , Seleção de Pacientes , Índice de Gravidade de Doença , Doadores Vivos , Listas de Espera
11.
PLoS Pathog ; 18(2): e1010288, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35167626

RESUMO

Urogenital schistosomiasis is caused by the blood fluke Schistosoma haematobium and is one of the most neglected tropical diseases worldwide, afflicting > 100 million people. It is characterised by granulomata, fibrosis and calcification in urogenital tissues, and can lead to increased susceptibility to HIV/AIDS and squamous cell carcinoma of the bladder. To complement available treatment programs and break the transmission of disease, sound knowledge and understanding of the biology and ecology of S. haematobium is required. Hybridisation/introgression events and molecular variation among members of the S. haematobium-group might effect important biological and/or disease traits as well as the morbidity of disease and the effectiveness of control programs including mass drug administration. Here we report the first chromosome-contiguous genome for a well-defined laboratory line of this blood fluke. An exploration of this genome using transcriptomic data for all key developmental stages allowed us to refine gene models (including non-coding elements) and annotations, discover 'new' genes and transcription profiles for these stages, likely linked to development and/or pathogenesis. Molecular variation within S. haematobium among some geographical locations in Africa revealed unique genomic 'signatures' that matched species other than S. haematobium, indicating the occurrence of introgression events. The present reference genome (designated Shae.V3) and the findings from this study solidly underpin future functional genomic and molecular investigations of S. haematobium and accelerate systematic, large-scale population genomics investigations, with a focus on improved and sustained control of urogenital schistosomiasis.


Assuntos
Variação Genética , Genoma de Protozoário , Schistosoma haematobium/genética , Esquistossomose Urinária/parasitologia , Transcriptoma , Animais , Cromossomos/parasitologia , Genes de Protozoários , Genoma , Estudo de Associação Genômica Ampla , Análise de Sequência de DNA
12.
BMC Microbiol ; 24(1): 28, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245715

RESUMO

BACKGROUND: Filarial worms are important vector-borne pathogens of a large range of animal hosts, including humans, and are responsible for numerous debilitating neglected tropical diseases such as, lymphatic filariasis caused by Wuchereria bancrofti and Brugia spp., as well as loiasis caused by Loa loa. Moreover, some emerging or difficult-to-eliminate filarioid pathogens are zoonotic using animals like canines as reservoir hosts, for example Dirofilaria sp. 'hongkongensis'. Diagnosis of filariasis through commonly available methods, like microscopy, can be challenging as microfilaremia may wane below the limit of detection. In contrast, conventional PCR methods are more sensitive and specific but may show limited ability to detect coinfections as well as emerging and/or novel pathogens. Use of deep-sequencing technologies obviate these challenges, providing sensitive detection of entire parasite communities, whilst also being better suited for the characterisation of rare or novel pathogens. Therefore, we developed a novel long-read metabarcoding assay for deep-sequencing the filarial nematode cytochrome c oxidase subunit I gene on Oxford Nanopore Technologies' (ONT) MinION™ sequencer. We assessed the overall performance of our assay using kappa statistics to compare it to commonly used diagnostic methods for filarial worm detection, such as conventional PCR (cPCR) with Sanger sequencing and the microscopy-based modified Knott's test (MKT). RESULTS: We confirmed our metabarcoding assay can characterise filarial parasites from a diverse range of genera, including, Breinlia, Brugia, Cercopithifilaria, Dipetalonema, Dirofilaria, Onchocerca, Setaria, Stephanofilaria and Wuchereria. We demonstrated proof-of-concept for this assay by using blood samples from Sri Lankan dogs, whereby we identified infections with the filarioids Acanthocheilonema reconditum, Brugia sp. Sri Lanka genotype and zoonotic Dirofilaria sp. 'hongkongensis'. When compared to traditionally used diagnostics, such as the MKT and cPCR with Sanger sequencing, we identified an additional filarioid species and over 15% more mono- and coinfections. CONCLUSIONS: Our developed metabarcoding assay may show broad applicability for the metabarcoding and diagnosis of the full spectrum of filarioids from a wide range of animal hosts, including mammals and vectors, whilst the utilisation of ONT' small and portable MinION™ means that such methods could be deployed for field use.


Assuntos
Coinfecção , Filariose , Filarioidea , Humanos , Animais , Cães , Filarioidea/genética , Filariose/diagnóstico , Filariose/veterinária , Filariose/parasitologia , Brugia/genética , Wuchereria bancrofti/genética , Mamíferos
13.
Hepatology ; 78(4): 1050-1063, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36089330

RESUMO

BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death. The NF-κB transcription factor family subunit c-Rel is typically protumorigenic; however, it has recently been reported as a tumor suppressor. Here, we investigated the role of c-Rel in HCC. APPROACH AND RESULTS: Histological and transcriptional studies confirmed expression of c-Rel in human patients with HCC, but low c-Rel expression correlated with increased tumor cell proliferation and mutational burden and was associated with advanced disease. In vivo , global ( Rel-/- ) and epithelial specific ( RelAlb ) c-Rel knockout mice develop more tumors, with a higher proliferative rate and increased DNA damage, than wild-type (WT) controls 30 weeks after N-diethylnitrosamine injury. However, tumor burden was comparable when c-Rel was deleted in hepatocytes once tumors were established, suggesting c-Rel signaling is important for preventing HCC initiation after genotoxic injury, rather than for HCC progression. In vitro , Rel-/- hepatocytes were more susceptible to genotoxic injury than WT controls. ATM-CHK2 DNA damage response pathway proteins were suppressed in Rel-/- hepatocytes following genotoxic injury, suggesting that c-Rel is required for effective DNA repair. To determine if c-Rel inhibition sensitizes cancer cells to chemotherapy, by preventing repair of chemotherapy-induced DNA damage, thus increasing tumor cell death, we administered single or combination doxorubicin and IT-603 (c-Rel inhibitor) therapy in an orthotopic HCC model. Indeed, combination therapy was more efficacious than doxorubicin alone. CONCLUSION: Hepatocyte c-Rel signaling limits genotoxic injury and subsequent HCC burden. Inhibiting c-Rel as an adjuvant therapy increased the effectiveness of DNA damaging agents and reduced HCC growth.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Dano ao DNA , Doxorrubicina/farmacologia , Hepatócitos/metabolismo , Neoplasias Hepáticas/metabolismo , Camundongos Knockout , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas c-rel/metabolismo
14.
Blood ; 139(12): 1833-1849, 2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35081253

RESUMO

Niemann-Pick disease type C1 (NP-C1) is a rare lysosomal storage disorder resulting from mutations in an endolysosomal cholesterol transporter, NPC1. Despite typically presenting with pronounced neurological manifestations, NP-C1 also resembles long-term congenital immunodeficiencies that arise from impairment of cytotoxic T lymphocyte (CTL) effector function. CTLs kill their targets through exocytosis of the contents of lysosome-like secretory cytotoxic granules (CGs) that store and ultimately release the essential pore-forming protein perforin and proapoptotic serine proteases, granzymes, into the synapse formed between the CTL and target cell. We discovered that NPC1 deficiency increases CG lipid burden, impairs autophagic flux through stalled trafficking of the transcription factor EB (TFEB), and dramatically reduces CTL cytotoxicity. Using a variety of immunological and cell biological techniques, we found that the cytotoxic defect arises specifically from impaired perforin pore formation. We demonstrated defects of CTL function of varying severity in patients with NP-C1, with the greatest losses of function associated with the most florid and/or earliest disease presentations. Remarkably, perforin function and CTL cytotoxicity were restored in vitro by promoting lipid clearance with therapeutic 2-hydroxypropyl-ß-cyclodextrin; however, restoration of autophagy through TFEB overexpression was ineffective. Overall, our study revealed that NPC1 deficiency has a deleterious impact on CTL (but not natural killer cell) cytotoxicity that, in the long term, may predispose patients with NP-C1 to atypical infections and impaired immune surveillance more generally.


Assuntos
Doença de Niemann-Pick Tipo A , Doença de Niemann-Pick Tipo C , Colesterol/metabolismo , Granzimas , Humanos , Doença de Niemann-Pick Tipo C/metabolismo , Perforina/genética , Linfócitos T Citotóxicos/metabolismo
15.
Diabetes Metab Res Rev ; 40(2): e3769, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38536196

RESUMO

OBJECTIVE: This manuscript aims to provide a review and synthesis of contemporary advancements in footwear, sensor technology for remote monitoring, and digital health, with a focus on improving offloading and measuring and enhancing adherence to offloading in diabetic foot care. METHODS: A narrative literature review was conducted by sourcing peer-reviewed articles, clinical studies, and technological innovations. This paper includes a review of various strategies, from specifically designed footwear, smart insoles and boots to using digital health interventions, which aim to offload plantar pressure and help prevent and manage wounds more effectively by improving the adherence to such offloading. RESULTS: In-house specially made footwear, sensor technologies remotely measuring pressure and weight-bearing activity, exemplified for example, through applications like smart insoles and SmartBoot, and other digital health technologies, show promise in improving offloading and changing patient behaviour towards improving adherence to offloading and facilitating personalised care. This paper introduces the concept of gamification and emotive visual indicators as novel methods to enhance patient engagement. It further discusses the transformative role of digital health technologies in the modern era. CONCLUSIONS: The integration of technology with footwear and offloading devices offers unparallelled opportunities for improving diabetic foot disease management not only through better offloading but also through improved adherence to offloading. These advancements allow healthcare providers to personalise treatment plans more effectively, thereby promising a major improvement in patient outcomes in diabetic foot ulcer healing and prevention.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Saúde Digital , Gerenciamento Clínico , Pessoal de Saúde , Sapatos
16.
Exp Physiol ; 109(9): 1505-1516, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38970776

RESUMO

Post-exercise hot (HWI) and cold (CWI) water immersion are popular strategies used by athletes in a range of sporting contexts, such as enhancing recovery or adaptation. However, prolonged heating bouts increase neuroendocrine responses that are associated with perceptions of fatigue. Fourteen endurance-trained runners performed three trials consisting of two 45-min runs at 95% lactate threshold on a treadmill separated by 6 h of recovery. Following the first run, participants completed one of HWI (30 min, 40°C), CWI (15 min, 14°C) or control (CON, 30 min rest in ambient conditions) in a randomised order. Perceived effort and recovery were measured using ratings of perceived exertion (RPE) and the Acute Recovery and Stress Scale (ARSS), whilst physiological responses including venous concentrations of a range of neuroendocrine markers, superficial femoral blood flow, heart rate and rectal temperature were measured. Exercise increased neuroendocrine responses of interleukin-6, adrenaline and noradrenaline (all P < 0.001). Additionally, perceptions of overall recovery (P < 0.001), mental performance capacity (P = 0.02), physical performance capability (P = 0.01) and emotional balance (P = 0.03) were reduced prior to the second run. However, there was no effect of condition on these variables (P > 0.05), nor RPE (P = 0.68), despite differences in rectal temperature, superficial femoral blood flow following the first run, and participants' expected recovery prior to the intervention (all P < 0.001). Therefore, athletes may engage in post-exercise hot or cold-water immersion without negatively impacting moderate-intensity training sessions performed later the same day.


Assuntos
Temperatura Baixa , Exercício Físico , Temperatura Alta , Imersão , Percepção , Esforço Físico , Humanos , Masculino , Adulto , Percepção/fisiologia , Exercício Físico/fisiologia , Esforço Físico/fisiologia , Frequência Cardíaca/fisiologia , Sistemas Neurossecretores/fisiologia , Adulto Jovem , Epinefrina/sangue , Norepinefrina/sangue , Água , Feminino , Interleucina-6/sangue
17.
Bioorg Med Chem ; 98: 117540, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38134663

RESUMO

Global challenges with treatment failures and/or widespread resistance in parasitic worms against commercially available anthelmintics lend impetus to the development of new anthelmintics with novel mechanism(s) of action. The free-living nematode Caenorhabditis elegans is an important model organism used for drug discovery, including the screening and structure-activity investigation of new compounds, and target deconvolution. Previously, we conducted a whole-organism phenotypic screen of the 'Pandemic Response Box' (from Medicines for Malaria Venture, MMV) and identified a hit compound, called ABX464, with activity against C. elegans and a related, parasitic nematode, Haemonchus contortus. Here, we tested a series of 44 synthesized analogues to explore the pharmacophore of activity on C. elegans and revealed five compounds whose potency was similar or greater than that of ABX464, but which were not toxic to human hepatoma (HepG2) cells. Subsequently, we employed thermal proteome profiling (TPP), protein structure prediction and an in silico-docking algorithm to predict ABX464-target candidates. Taken together, the findings from this study contribute significantly to the early-stage drug discovery of a new nematocide based on ABX464. Future work is aimed at validating the ABX464-protein interactions identified here, and at assessing ABX464 and associated analogues against a panel of parasitic nematodes, towards developing a new anthelmintic with a mechanism of action that is distinct from any of the compounds currently-available commercially.


Assuntos
Anti-Helmínticos , Nematoides , Quinolinas , Animais , Humanos , Caenorhabditis elegans , Anti-Helmínticos/farmacologia , Anti-Helmínticos/química , Relação Estrutura-Atividade
18.
Bioorg Med Chem ; 100: 117618, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38309201

RESUMO

The virally encoded 3C-like protease (3CLpro) is a well-validated drug target for the inhibition of coronaviruses including Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Most inhibitors of 3CLpro are peptidomimetic, with a γ-lactam in place of Gln at the P1 position of the pseudopeptide chain. An effort was pursued to identify a viable alternative to the γ-lactam P1 mimetic which would improve physicochemical properties while retaining affinity for the target. Discovery of a 2-tetrahydrofuran as a suitable P1 replacement that is a potent enzymatic inhibitor of 3CLpro in SARS-CoV-2 virus is described herein.


Assuntos
Antivirais , Inibidores de Protease de Coronavírus , Furanos , Antivirais/química , Antivirais/farmacologia , Lactamas , Peptídeo Hidrolases , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , SARS-CoV-2 , Furanos/química , Inibidores de Protease de Coronavírus/química
19.
Curr Psychiatry Rep ; 26(1): 9-25, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38183600

RESUMO

PURPOSE OF REVIEW: Emotions are prominent in theories and accounts of schizophrenia but are largely understudied compared to cognition. Utilizing the Research Domain Criteria (RDoC) Negative Valence Systems framework, we review the current knowledge of emotions in schizophrenia. Given the pivotal role of threat responses in theories of schizophrenia and the substantial evidence of altered threat responses, we focus on three components of Negative Valence Systems tied to threat responses: responses to acute threat, responses to potential threat, and sustained threat. RECENT FINDINGS: Individuals with schizophrenia show altered responses to neutral stimuli during acute threat, bed nucleus of the stria terminalis connectivity in response to potential threat, and threat responses associated with sustained threat. Our review concludes that Negative Valence Systems are altered in schizophrenia; however, the level and evidence of alterations vary across the types of threat responses. We suggest avenues for future research to further understand and intervene on threat responses in schizophrenia.


Assuntos
Esquizofrenia , Núcleos Septais , Humanos , Medo/fisiologia , Núcleos Septais/fisiologia , Emoções , Cognição
20.
J Hered ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248324

RESUMO

Polyergus kidnapper ants are widely distributed, but relatively uncommon, throughout the Holarctic, spanning an elevational range from sea level to over 3000 m. These species are well known for their obligate social parasitism with various Formica ant species, which they kidnap in dramatic, highly coordinated raids. Kidnapped Formica larvae and pupae become integrated into the Polyergus colony where they develop into adults and perform nearly all of the necessary colony tasks for the benefit of their captors. In California, Polyergus mexicanus is the most widely distributed Polyergus, but recent evidence has identified substantial genetic polymorphism within this species, including genetically divergent lineages associated with the use of different Formica host species. Given its unique behavior and genetic diversity, Polyergus mexicanus plays a critical role in maintaining ecosystem balance by influencing the population dynamics and genetic diversity of its host ant species, Formica, highlighting its conservation value and importance in the context of biodiversity preservation. Here, we present a high-quality genome assembly of P. mexicanus from a sample collected in Plumas County, CA, USA, in the foothills of the central Sierra Nevada. This genome assembly consists of 364 scaffolds spanning 252.31 Mb, with contig N50 of 481,250 kb, scaffold N50 of 10.36 Mb, and BUSCO completeness of 95.4%. We also assembled the genome of the Wolbachia endosymbiont of P. mexicanus - a single, circular contig spanning 1.23 Mb. These genome sequences provide essential resources for future studies of conservation genetics, population genetics, speciation, and behavioral ecology in this charismatic social insect.

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