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Africa's potential for scientific research is not yet being realized, for various reasons including a lack of researchers in many fields and insufficient funding. Strengthened research capacity through doctoral training programmes in higher education institutes (HEIs) in Africa, to include collaboration with national, regional and international research institutions, can facilitate self-reliant and sustainable research to support socio-economic development. In 2012, the Royal Society and the UK's Department for International Development (now the Foreign, Commonwealth and Development Office) launched the Africa Capacity Building Initiative (ACBI) Doctoral Training Network which aimed to strengthen research capacity and training across sub-Saharan Africa. The ACBI supported 30 core PhD scholarships, all registered/supervised within African HEIs with advisory support from the UK-based institutes. Our 'Soil geochemistry to inform agriculture and health policies' consortium project, which was part of the ACBI doctoral training programme network, was implemented in Malawi, Zambia and Zimbabwe between 2014 and 2020. The aims of our consortium were to explore linkages between soil geochemistry, agriculture and public health for increased crop productivity, nutrition and safety of food systems and support wider training and research activities in soil science. Highlights from our consortium included: (i) the generation of new scientific evidence on linkages between soils, crops and human nutrition; (ii) securing new projects to translate science into policy and practice; and (iii) maintaining sustainable collaborative learning across the consortium. Our consortium delivered high-quality science outputs and secured new research and doctoral training funding from a variety of sources to ensure the continuation of research and training activities. For example, follow-on Global Challenges Research Funded Translation Award provided a strong evidence base on the prevalence of deficiencies in children under 5 years of age and women of reproductive age in Zimbabwe. This new evidence will contribute towards the design and implementation of a nationally representative micronutrient survey as an integral part of the Zimbabwe Demographic and Health Surveys conducted by the Ministry of Health and Child Care. The award also generated new evidence and a road map for creating quality innovative doctorates through a doctoral training landscape activity led by the Zimbabwe Council for Higher Education. Although our project and the wider ACBI has contributed to increasing the self-reliance and sustainability of research within the region, many challenges remain and ongoing investment is required.
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In the underdoped n-type cuprate Nd2-xCexCuO4, long-range antiferromagnetic order reconstructs the Fermi surface, resulting in a putative antiferromagnetic metal with small Fermi pockets. Using angle-resolved photoemission spectroscopy, we observe an anomalous energy gap, an order of magnitude smaller than the antiferromagnetic gap, in a wide portion of the underdoped regime and smoothly connecting to the superconducting gap at optimal doping. After considering all the known ordering tendencies in tandem with the phase diagram, we hypothesize that the normal-state gap in the underdoped n-type cuprates originates from Cooper pairing. The high temperature scale of the normal-state gap raises the prospect of engineering higher transition temperatures in the n-type cuprates comparable to those of the p-type cuprates.
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Hypertension is among the most important risk factors for cardiovascular disease, chronic kidney disease, and dementia. The artificial intelligence (AI) field is advancing quickly, and there has been little discussion on how AI could be leveraged for improving the diagnosis and management of hypertension. AI technologies, including machine learning tools, could alter the way we diagnose and manage hypertension, with potential impacts for improving individual and population health. The development of successful AI tools in public health and health care systems requires diverse types of expertise with collaborative relationships between clinicians, engineers, and data scientists. Unbiased data sources, management, and analyses remain a foundational challenge. From a diagnostic standpoint, machine learning tools may improve the measurement of blood pressure and be useful in the prediction of incident hypertension. To advance the management of hypertension, machine learning tools may be useful to find personalized treatments for patients using analytics to predict response to antihypertension medications and the risk for hypertension-related complications. However, there are real-world implementation challenges to using AI tools in hypertension. Herein, we summarize key findings from a diverse group of stakeholders who participated in a workshop held by the National Heart, Lung, and Blood Institute in March 2023. Workshop participants presented information on communication gaps between clinical medicine, data science, and engineering in health care; novel approaches to estimating BP, hypertension risk, and BP control; and real-world implementation challenges and issues.
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The accessibility of the retina with the use of non-invasive and relatively low-cost ophthalmic imaging techniques and analytics provides a unique opportunity to improve the detection, diagnosis and monitoring of systemic diseases. The National Heart, Lung, and Blood Institute conducted a workshop in October 2022 to examine this concept. On the basis of the discussions at that workshop, this Roadmap describes current knowledge gaps and new research opportunities to evaluate the relationships between the eye (in particular, retinal biomarkers) and the risk of cardiovascular diseases, including coronary artery disease, heart failure, stroke, hypertension and vascular dementia. Identified gaps include the need to simplify and standardize the capture of high-quality images of the eye by non-ophthalmic health workers and to conduct longitudinal studies using multidisciplinary networks of diverse at-risk populations with improved implementation and methods to protect participant and dataset privacy. Other gaps include improving the measurement of structural and functional retinal biomarkers, determining the relationship between microvascular and macrovascular risk factors, improving multimodal imaging 'pipelines', and integrating advanced imaging with 'omics', lifestyle factors, primary care data and radiological reports, by using artificial intelligence technology to improve the identification of individual-level risk. Future research on retinal microvascular disease and retinal biomarkers might additionally provide insights into the temporal development of microvascular disease across other systemic vascular beds.
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AIM: The primary aim of this study was to determine the selenium (Se) and iodine (I) food concentrations and dietary intake of the population living in the Kurdish controlled region of northern Iraq. We also assessed the extent to which iodised salt contributes to dietary iodine intake. METHODOLOGY: Foods and samples of salt and drinking water were analysed, including 300 crops samples from 40 local farms. The results, supplemented by food composition data, were used to assess dietary Se and I intake for 410 volunteers using a semi-quantitative food questionnaire. To directly investigate the nutritional status of individuals, urine samples were also collected from participants. RESULTS: Selenium intake was mainly supplied by protein and cereal sources. Calculated median dietary intake of Se was 62.7⯵g d-1 (mean = 66.3⯵g d-1) with c. 72â¯% of participants meeting or exceeding dietary reference intake recommendations for age. Median dietary intake of I, excluding salt consumption, was 94.6⯵g d-1 (mean 100.2⯵g d-1), increasing to 607.2⯵g d-1 when salt (of which >90â¯% was iodized) was included. Salt intake was estimated to be c.13.5â¯g d-1 (5400â¯mg Na d-1) which greatly exceeds WHO recommended intake (< 2000â¯mg d-1 of Na). Urine iodine concentrations indicated that 98â¯% of school aged children had excessive iodine intake (≥300⯵gâ¯L-1) and 80-90â¯% of all study participants had above average or excessive iodine intake (≥200⯵gâ¯L-1). CONCLUSIONS: Poultry and rice are the main sources of dietary Se to this population but around a third of children receive an inadequate Se intake. Fresh fruit and vegetables are the main sources of dietary I, but consumption of local foods cannot supply adequate I without iodised salt supplementation. Consumption of iodized salt well above recommended amounts is supplying this population with substantial iodine intake. Interventions to reduce salt intake would help to limit excessive iodine intake whilst also reducing cardio-vascular risks from Na consumption.
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Iodo , Estado Nutricional , Selênio , Iodo/urina , Iodo/administração & dosagem , Iodo/análise , Humanos , Selênio/análise , Selênio/urina , Selênio/administração & dosagem , Iraque , Masculino , Feminino , Adulto , Criança , Adolescente , Pessoa de Meia-Idade , Adulto Jovem , Dieta , Cloreto de Sódio na Dieta/análise , Cloreto de Sódio na Dieta/administração & dosagem , Pré-EscolarRESUMO
Immune checkpoint inhibitors are effective first-line therapy for solid cancers. However, low response rate and acquired resistance over time has led to the need for additional therapeutic options. Here, we evaluated synergistic antitumor efficacy of EGFR × MET targeting bispecific antibody, amivantamab with PD-L1 immunotherapy, pembrolizumab in head and neck squamous cell carcinoma (HNSCC) and lung squamous cell carcinoma tumor-bearing humanized patient-derived xenograft (PDX) models. We demonstrated that pembrolizumab or amivantamab alone was ineffective and that combination treatment induced a significant reduction of tumor growth in both models (P < 0.0001 and P < 0.01, respectively). It appeared that combination of amivantamab and pembrolizumab significantly enhanced infiltration of granzyme B-producing CD8 T cells was in the TME of HNSCC PDX (P < 0.01) and enhanced neoantigen-associated central memory CD8 T cells in circulating immune cells. Analysis of single-cell RNA transcriptomics suggested that the tumor cells dramatically upregulated EGFR and MET in response to PD-L1 immunotherapy, potentially creating a metabolic state fit for tumor persistence in the tumor microenvironment (TME) and rendered pembrolizumab ineffective. We demonstrated that EGFRHIGHMETHIGH subcluster displayed an increased expression of genes implicated in production of lactate [SLC16A3 and lactate dehydrogenase A (LDHA)] compared to the EGFRLOWMETLOW cluster. Accumulation of lactate in the TME has been associated with immunosuppression by hindering the infiltration of tumor killing CD8 T and NK cells. This study proved that amivantamab reduced glycolytic markers in the EGFRHIGHMETHIGH subcluster including SLC16A3 and LDHA and highlighted remodeling of the TME by combination treatment, providing rationale for additional therapy of amivantamab with PD-1 immunotherapy. SIGNIFICANCE: Amivantamab in synergy with pembrolizumab effectively eradicated EGFRHIGHMETHIGH tumor subcluster in the tumor microenvironment of head and neck squamous cell carcinoma and overcame resistance against anti-PD-1 immunotherapy.
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Anticorpos Monoclonais Humanizados , Neoplasias Pulmonares , Carcinoma de Células Escamosas de Cabeça e Pescoço , Microambiente Tumoral , Humanos , Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/imunologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Animais , Camundongos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Antígeno B7-H1/metabolismo , Linhagem Celular TumoralRESUMO
Porcine respiratory coronavirus (PRCV) is a member of the species Alphacoronavirus 1 within the genus Alphacoronavirus of the family Coronaviridae. A few studies have been conducted on the prevalence of PRCV since its first identification in 1997, but there have been no recent studies on the prevalence and genetic characterization of the virus in Korea. In this study, the seroprevalence of PRCV was determined in Korean pig farms using a commercially available TGEV/PRCV differential enzyme-linked immunosorbent assay kit. The farm-level seroprevalence of PRCV was determined to be 68.6% (48/70), similar to previous reports in Korea, suggesting that PRCV is still circulating in Korean pig herds nationwide. Among the 20 PRCV-seropositive farms tested in this study, PRCV RNAs were detected in 17 oral fluid samples (28.3%) from nine farms (45.0%), while TGEV RNAs were not detected in any sample. To investigate the genetic characteristics of Korean PRCV strains, genetic and phylogenetic analyses were conducted on PRCV spike gene sequences obtained in this study. The three Korean PRCV strains (KPRCV2401, KPRCV2402, and KPRCV2403) shared 98.5-100% homology with each other and 96.2-96.6% and 91.6-94.5% homology with European and American strains, respectively. A 224-amino acid deletion was found in the S gene of both Korean and European PRCVs but not in that of American PRCVs, suggesting a European origin for Korean PRCVs. Phylogenetic analysis showed that Korean PRCVs are more closely related to European PRCVs than American PRCVs but clustered apart from both, suggesting that Korean PRCV has evolved independently since its emergence in Korean PRCVs. The results of this study will help expand knowledge on the epidemiology and molecular biology of PRCV currently circulating in Korea.
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Chronic liver diseases are caused by hepatic viral infection, chemicals, and metabolic stress. The protein Grb2-associated binder 1 (Gab1) binds to various growth factor receptors, and triggers cell differentiation/survival signaling pathways. To identify signaling molecules involved in the progression of liver diseases, we performed reverse-phase protein microarray (RPMA)-based screening of hepatocytes isolated from humanized mice after acute HCV infection. Acute viral infection in humanized liver mice significantly decreased the level of hepatocyte p-Gab1. Moreover, hepatoma cells upon HCV infection decreased Gab1 mRNA at later times of infection (D3 to D5) and p-Gab1 level was inversely related to the production of TGF-ß. In contrast, the level of p-Gab1 was increased in CCL4-induced fibrotic liver. Hepatoma cells showed elevation of p-Gab1, along with an increase in STAT3 and ERK activation, upon treatment with HGF (ligand of HGF receptor/c-Met) and CCL4. In Gab1 knockdown hepatoma cells, cell proliferative signaling activity was reduced but the level of activated caspase-3 was increased. These findings suggest that hepatocyte Gab1 expression may play a role in promoting liver fibrosis progression by triggering ERK activation and inhibiting apoptosis. It implies that the Gab1-mediated signaling pathway would be a promising therapeutic target to treat chronic liver diseases.
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Proteínas Adaptadoras de Transdução de Sinal , Apoptose , Proliferação de Células , Fator de Crescimento de Hepatócito , Hepatócitos , Cirrose Hepática , Proteínas Proto-Oncogênicas c-met , Transdução de Sinais , Animais , Hepatócitos/metabolismo , Hepatócitos/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-met/metabolismo , Fator de Crescimento de Hepatócito/metabolismo , Linhagem Celular Tumoral , Hepatite C/metabolismo , Hepatite C/patologia , Hepatite C/complicaçõesRESUMO
PURPOSE: Tissue-derived tumor mutation burden (TMB) of ≥10 mutations/Mb is a histology-agnostic biomarker for the immune checkpoint inhibitor (ICI) pembrolizumab. However, the dataset in which this was validated lacked colorectal cancers (CRC), and there is limited evidence for immunotherapy benefits in CRC using this threshold. PATIENTS AND METHODS: CO.26 was a randomized phase II study of 180 patients, comparing durvalumab and tremelimumab (D + T, n = 119 patients) versus best supportive care (BSC; n = 61 patients). ctDNA sequencing was available for 168 patients (n = 118 D + T; n = 50), of whom 165 had evaluable plasma TMB (pTMB). Tissue sequencing was available for 108 patients. Optimal thresholds for stratifying patients based on OS were determined using a minimal P value approach. This report includes the final OS analysis. RESULTS: Tissue TMB ≥10 mutations/Mb was not predictive of benefit from D + T compared with BSC in microsatellite stable (MSS) metastatic CRC [HR, 0.71 (95% CI, 0.28-1.80); P = 0.47]. No tissue TMB threshold could identify a high TMB group that benefited from ICI. By contrast, plasma TMB (pTMB) ≥28 mutations/Mb was predictive of benefit from D + T [HR, 0.34 (95% CI, 0.13-0.85); P = 0.022], as was clonal pTMB ≥10.6 mutations/Mb [HR, 0.10 (95% CI, 0.014-0.79); P = 0.029] and subclonal pTMB ≥25.9/Mb [HR, 0.20 (95% CI, 0.061-0.69); P = 0.010]. Higher pTMB was associated with length of time on cytotoxic agents (P = 0.021) and prior anti-EGFR exposure (P = 2.44 × 10-06). CONCLUSIONS: pTMB derived from either clonal or subclonal mutations may identify a group likely to benefit from immunotherapy, although validation is required. Tissue TMB provided no predictive utility for immunotherapy in this trial.
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Anticorpos Monoclonais Humanizados , Anticorpos Monoclonais , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores Tumorais , Neoplasias Colorretais , Mutação , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Biomarcadores Tumorais/genética , Feminino , Masculino , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Pessoa de Meia-Idade , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Adulto , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/administração & dosagem , Idoso de 80 Anos ou mais , Metástase NeoplásicaRESUMO
Material design is increasingly used to realize desired functional properties, and the perovskite structure family is one of the richest and most diverse: perovskites are employed in many applications due to their structural flexibility and compositional diversity. Hexagonal, layered perovskite structures with chains of face-sharing transition metal oxide octahedra have attracted great interest as quantum materials due to their magnetic and electronic properties. Ba4MMn3O12, a member of the "12R" class of hexagonal, layered perovskites, contains trimers of face-sharing MnO6 octahedra that are linked by a corner-sharing, bridging MO6 octahedron. Here, we investigate cluster magnetism in the Mn3O12 trimers and the role of this bridging octahedron on the magnetic properties of two isostructural 12R materials by systematically changing the M4+ cation from nonmagnetic Ce4+ (f0) to magnetic Pr4+ (f1). We synthesized 12R-Ba4MMn3O12 (M= Ce, Pr) with high phase purity and characterized their low-temperature crystal structures and magnetic properties. Using substantially higher purity samples than previously reported, we confirm the frustrated antiferromagnetic ground state of 12R-Ba4PrMn3O12 below TN ≈ 7.75 K and explore the cluster magnetism of its Mn3O12 trimers. Despite being atomically isostructural with 12R-Ba4CeMn3O12, the f1 electron associated with Pr4+ causes much more complex magnetic properties in 12R-Ba4PrMn3O12. In 12R-Ba4PrMn3O12, we observe a sharp, likely antiferromagnetic transition at T2 ≈ 12.15 K and an additional transition at T1 ≈ 200 K, likely in canted antiferromagnetic order. These results suggest that careful variation of composition within the family of hexagonal, layered perovskites can be used to tune material properties using the complex role of the Pr4+ ion in magnetism.
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BACKGROUND: Despite ongoing improvements to regimens preventing allograft rejection, most cardiac and other organ grafts eventually succumb to chronic vasculopathy, interstitial fibrosis, or endothelial changes, and eventually graft failure. The events leading to chronic rejection are still poorly understood and the gut microbiota is a known driving force in immune dysfunction. We previously showed that gut microbiota dysbiosis profoundly influences the outcome of vascularized cardiac allografts and subsequently identified biomarker species associated with these differential graft outcomes. METHODS: In this study, we further detailed the multifaceted immunomodulatory properties of protolerogenic and proinflammatory bacterial species over time, using our clinically relevant model of allogenic heart transplantation. RESULTS: In addition to tracing longitudinal changes in the recipient gut microbiome over time, we observed that Bifidobacterium pseudolongum induced an early anti-inflammatory phenotype within 7 d, whereas Desulfovibrio desulfuricans resulted in a proinflammatory phenotype, defined by alterations in leukocyte distribution and lymph node (LN) structure. Indeed, in vitro results showed that B pseudolongum and D desulfuricans acted directly on primary innate immune cells. However, by 40 d after treatment, these 2 bacterial strains were associated with mixed effects in their impact on LN architecture and immune cell composition and loss of colonization within gut microbiota, despite protection of allografts from inflammation with B pseudolongum treatment. CONCLUSIONS: These dynamic effects suggest a critical role for early microbiota-triggered immunologic events such as innate immune cell engagement, T-cell differentiation, and LN architectural changes in the subsequent modulation of protolerant versus proinflammatory immune responses in organ transplant recipients.
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Bifidobacterium , Microbioma Gastrointestinal , Rejeição de Enxerto , Transplante de Coração , Transplante de Coração/efeitos adversos , Microbioma Gastrointestinal/imunologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/microbiologia , Rejeição de Enxerto/prevenção & controle , Animais , Masculino , Fatores de Tempo , Sobrevivência de Enxerto , Disbiose , Camundongos Endogâmicos C57BL , Imunidade Inata , Imunomodulação , Fenótipo , Probióticos/uso terapêutico , Linfonodos/microbiologia , Linfonodos/imunologiaRESUMO
The response of an oxide crystal to the atmosphere can be personified as breathing-a dynamic equilibrium between O2 gas and O2- anions in the solid. We characterize the analogous defect reaction in an iodide double-perovskite semiconductor, Cs2SnI6. Here, I2 gas is released from the crystal at room temperature, forming iodine vacancies. The iodine vacancy defect is a shallow electron donor and is therefore ionized at room temperature; thus, the loss of I2 is accompanied by spontaneous n-type self-doping. Conversely, at high I2 pressures, I2 gas is resorbed by the perovskite, consuming excess electrons as I2 is converted to 2I-. Halide mobility and irreversible halide loss or exchange reactions have been studied extensively in halide perovskites. However, the reversible exchange equilibrium between iodide and iodine [2I-(s) â I2(g) + 2e-] described here has often been overlooked in prior studies, though it is likely general to halide perovskites and operative near room temperature, even in the dark. An analysis of the 2I-(s)/I2(g) equilibrium thermodynamics and related transport kinetics in single crystals of Cs2SnI6 therefore provides insight toward achieving stable composition and electronic properties in the large family of iodide perovskite semiconductors.
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AIM: To evaluate and compare the rates of local recurrence in hepatocellular carcinoma (HCC) patients who undergo selective transarterial radioembolisation (TARE) or transarterial chemoembolisation (TACE) and achieve a complete response (CR) radiologically. MATERIALS AND METHODS: All patients undergoing treatment with TARE or TACE at a single academic institution were reviewed retrospectively. Those who had been treated previously, presented with multifocal disease, had non-selective TARE or TACE, or did not achieve a complete response (CR) radiologically were excluded. RESULTS: In total 110 patients were included (TACE n=60 [54.5%]; TARE n=50 [45.5%]). TARE patients were older (66.4 ± 9.4 versus 61.2 ± 5.6 years, p<0.001) and had larger tumours (4.4 ± 2.2 versus 3 ± 1.4 cm, p=0.002). TACE patients were significantly more likely to suffer a local recurrence (31/60, 51.7% versus 9/50, 18%, p<0.001) and had a significantly shorter time to recurrence (median 8.3 {interquartile range [IQR]}: 12 versus median 17.9 [IQR: 23.5] months, p=0.001). A local time to progression (TTP) Kaplan-Meier curve demonstrated TACE patients had a significantly shorter local TTP (hazard ratio [HR]: 7.2; 95% confidence interval [CI]: 3.64-14.24; p<0.001) and treatment modality (TACE or TARE; HR: 0.05; 95% CI: 0.005-0.5; p=0.01) was found to be associated with local recurrences on multivariate Cox proportional HR analysis. When overall TTP was evaluated, again TACE patients were found to have a significantly shorter TTP (HR: 2.13 [1.28-3.53], p=0.004). CONCLUSION: In HCC patients undergoing selective treatment who achieve a CR radiologically, those treated with TARE may be less likely to suffer recurrence, either local or general, than those treated with TACE.
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Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/etiologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/etiologia , Estudos Retrospectivos , Quimioembolização Terapêutica/efeitos adversos , Modelos de Riscos Proporcionais , Resposta Patológica Completa , Resultado do TratamentoRESUMO
Electrostatic gating has emerged as a powerful technique for tailoring the magnetic properties of two-dimensional (2D) magnets, offering exciting prospects including enhancement of magnetic anisotropy, boosting Curie temperature, and strengthening exchange coupling effects. Here, we focus on electrical control of the ferromagnetic resonance of the quasi-2D Kagome magnet Cu(1,3-bdc). By harnessing an electrostatic field through ionic liquid gating, significant shifts are observed in the ferromagnetic resonance field in both out-of-plane and in-plane measurements. Moreover, the effective magnetization and gyromagnetic ratios display voltage-dependent variations. A closer examination reveals that the voltage-induced changes can modulate magnetocrystalline anisotropy by several hundred gauss, while the impact on orbital magnetization remains relatively subtle. Density functional theory (DFT) calculations reveal varying d-orbital hybridizations at different voltages. This research unveils intricate physics within the Kagome lattice magnet and further underscores the potential of electrostatic manipulation in steering magnetism with promising implications for the development of spintronic devices.
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Activation and clonal expansion of the Ag-specific adaptive immune response in the draining lymph node is essential to clearing influenza A virus infections. Activation sufficient for virus clearance is dependent on the lymph node's architectural organization that is maintained by stromal cells, chiefly fibroblastic reticular cells. During an analysis of influenza A virus clearance in leptin receptor knockout (DB/DB) mice, we observed that the DB/DB mice have markedly reduced numbers of lymph node fibroblastic reticular cells at the steady state. The reduction in lymph node fibroblastic reticular cells resulted in abnormal lymph node organization and diminished numbers of adaptive immune cells in the lymph nodes under homeostatic conditions. As a consequence, the DB/DB mice were impaired in their ability to generate an effective influenza-specific adaptive immune response, which prevented virus clearance. Using leptin receptor mutant mice with point mutations at distinct signaling sites in the leptin receptor, we were able to link the leptin receptor's signaling domain tyrosine 985, which does not contribute to obesity, to lymph node fibroblastic reticular cell development and function. These results demonstrate a novel role for leptin receptor signaling in regulating lymph node development in a manner that is crucial to the generation of Ag-specific adaptive immune responses.
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Imunidade Adaptativa , Receptores para Leptina , Camundongos , Animais , Receptores para Leptina/genética , Linfonodos , Transdução de Sinais , Camundongos Endogâmicos C57BL , LeptinaRESUMO
Spontaneous tumour regression is a rare but well-documented phenomenon, especially for renal cell carcinomas. We describe the case of a 60-year-old male who presented with chest pain and shortness of breath. He was diagnosed with a large type A aortic dissection and an incidental right renal mass, highly suspicious of a renal cell carcinoma. Following repair of the dissection, subsequent imaging showed that the renal mass had largely resolved. Spontaneous tumour regression is commonly thought to occur through immunological mechanisms. A vascular cause of tumour regression through infarction is postulated in this case. Although angioembolisation is a well-recognised management option in the context of palliative treatment of symptomatic renal tumours, this case suggests an extended role for angioembolisation in the treatment of small renal masses.
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Dissecção Aórtica , Carcinoma de Células Renais , Neoplasias Renais , Masculino , Humanos , Pessoa de Meia-Idade , Rim/irrigação sanguínea , Dissecção Aórtica/diagnóstico por imagem , Carcinoma de Células Renais/diagnóstico por imagem , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Artéria RenalRESUMO
Novel swine orthopneumovirus (SOV) infections have been identified in pigs in the USA and some European countries but not in Asian countries, including South Korea, to date. The current study reports the first SOV infections in four domestic pig farms located in four provinces across South Korea. The detection rate of SOV in oral fluid samples using qRT-PCR was 4.4% (14/389), indicating the presence of the virus in pigs at commercial farms in Korea. Two complete genome sequences and one glycoprotein (G) gene sequence were obtained from SOV-positive samples. The complete genome analysis of KSOV-2201 and KSOV-2202 strains showed 98.2 and 95.4% homologies with a previously reported SOV, and the phylogenetic tree exhibited a high correlation with a previously reported SOV strain from the US and a canine pneumovirus (CPnV) strain from China. Based on the genetic analysis of the viral G gene, the murine pneumonia virus (MPV)-like orthopneumoviruses (MLOVs) were divided into two genogroups (G1 and G2). Seventeen CPnVs and two feline pneumoviruses were grouped into G1, while the Korean SOV strains identified in this study were grouped into G2 along with one SOV and two CPnVs. These results will contribute to expanding our understanding of the geographical distribution and genetic characteristics of the novel SOV in the global pig population.
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Pneumovirus , Doenças dos Suínos , Camundongos , Suínos , Animais , Gatos , Cães , Sus scrofa , Vírus Sinciciais Respiratórios , Fazendas , Filogenia , Doenças dos Suínos/epidemiologia , República da Coreia/epidemiologiaRESUMO
Increasing the chemical diversity of organic semiconductors is essential to develop efficient electronic devices. In particular, the replacement of carbon-carbon (C-C) bonds with isoelectronic boron-nitrogen (B-N) bonds allows precise modulation of the electronic properties of semiconductors without significant structural changes. Although some researchers have reported the preparation of B2 N2 anthracene derivatives with two B-N bonds, no compounds with continuous multiple BN units have been prepared yet. Herein, we report the synthesis and characterization of a B2 N2 anthracene derivative with a BNBN unit formed by converting the BOBN unit at the zigzag edge. Compared to the all-carbon analogue 2-phenylanthracene, BNBN anthracene exhibits significant variations in the C-C bond length and a larger highest occupied molecular orbital-lowest unoccupied molecular orbital energy gap. The experimentally determined bond lengths and electronic properties of BNBN anthracene are confirmed through theoretical calculations. The BOBN anthracene organic light-emitting diode, used as a blue host, exhibits a low driving voltage. The findings of this study may facilitate the development of larger acenes with multiple BN units and potential applications in organic electronics.
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Immune mediated graft loss still represents a major risk to transplant recipients. Creative approaches to immunosuppression that exploit the recipient's own alloregulatory mechanisms could reduce the need for pharmacologic immunosuppression and potentially induce immune tolerance. In the process of studying recipient derived myeloid derived suppressor cells (MDSCs), we identified key alloregulatory MDSC mechanisms, mediated by isolatable proteins IL-4, IL-34, and IL-10. We sought to purify these proteins and fuse them for subsequent infusion into transplant recipients as a means of inducing an alloregulatory response. In this introductory investigation, we leveraged molecular engineering technology to create a fusion protein (FP) of three cytokine coding sequences of IL-4, IL-34, and IL-10 and demonstrated their expressions by Western Blot analysis. Following purification, we tested whether FP IL-4/IL-34/IL-10 (FP1) can protect heart transplant allografts. Injection of FP1 significantly prolonged allogeneic cardiac graft survival in a dose-dependent fashion and the increase of graft survival time exceeded survival attributable to IL-34 alone. In vitro, MDSCs cells were expanded by FP1 treatment. However, FP1 did not directly inhibit T cell proliferation in vitro. In conclusion, newly developed FP1 improves the graft survival in cardiac transplantation mouse model. Significant additional work to optimize FP1 or include other novel proteins could supplement current treatment options for transplant patients.
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Transplante de Coração , Interleucina-10 , Humanos , Animais , Camundongos , Interleucina-10/genética , Interleucina-4 , Doadores de Tecidos , Aloenxertos , Camundongos Endogâmicos C57BLRESUMO
Although Cu2+ is ubiquitous, the relativistic destabilization of the 5d orbitals makes the isoelectronic Au2+ exceedingly rare, typically stabilized only through Au-Au bonding or by using redox non-innocent ligands. Here we report the perovskite Cs4AuIIAuIII2Cl12, an extended solid with mononuclear Au2+ sites, which is stable to ambient conditions and characterized by single-crystal X-ray diffraction. The 2+ oxidation state of Au was assigned using 197Au Mössbauer spectroscopy, electron paramagnetic resonance, and magnetic susceptibility measurements, with comparison to paramagnetic and diamagnetic analogues with Cu2+ and Pd2+, respectively, as well as to density functional theory calculations. This gold perovskite offers an opportunity to study the optical and electronic transport of the uncommon Au2+/3+ mixed-valence state and the characteristics of the elusive Au2+ ion coordinated to simple ligands. Compared with the perovskite Cs2AuIAuIIICl6, which has been studied since the 1920s, Cs4AuIIAuIII2Cl12 exhibits a 0.7 eV reduction in optical absorption onset and a 103-fold increase in electronic conductivity.