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1.
Cell ; 184(10): 2649-2664.e18, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33848463

RESUMO

Receptor tyrosine kinase (RTK)-mediated activation of downstream effector pathways such as the RAS GTPase/MAP kinase (MAPK) signaling cascade is thought to occur exclusively from lipid membrane compartments in mammalian cells. Here, we uncover a membraneless, protein granule-based subcellular structure that can organize RTK/RAS/MAPK signaling in cancer. Chimeric (fusion) oncoproteins involving certain RTKs including ALK and RET undergo de novo higher-order assembly into membraneless cytoplasmic protein granules that actively signal. These pathogenic biomolecular condensates locally concentrate the RAS activating complex GRB2/SOS1 and activate RAS in a lipid membrane-independent manner. RTK protein granule formation is critical for oncogenic RAS/MAPK signaling output in these cells. We identify a set of protein granule components and establish structural rules that define the formation of membraneless protein granules by RTK oncoproteins. Our findings reveal membraneless, higher-order cytoplasmic protein assembly as a distinct subcellular platform for organizing oncogenic RTK and RAS signaling.


Assuntos
Condensados Biomoleculares/metabolismo , Grânulos Citoplasmáticos/metabolismo , Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Proteínas ras/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Ativação Enzimática , Proteína Adaptadora GRB2/genética , Proteína Adaptadora GRB2/metabolismo , Células HEK293 , Humanos , Proteína SOS1/metabolismo , Transdução de Sinais
2.
Nature ; 619(7969): 317-322, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37438590

RESUMO

Plastic debris is thought to be widespread in freshwater ecosystems globally1. However, a lack of comprehensive and comparable data makes rigorous assessment of its distribution challenging2,3. Here we present a standardized cross-national survey that assesses the abundance and type of plastic debris (>250 µm) in freshwater ecosystems. We sample surface waters of 38 lakes and reservoirs, distributed across gradients of geographical position and limnological attributes, with the aim to identify factors associated with an increased observation of plastics. We find plastic debris in all studied lakes and reservoirs, suggesting that these ecosystems play a key role in the plastic-pollution cycle. Our results indicate that two types of lakes are particularly vulnerable to plastic contamination: lakes and reservoirs in densely populated and urbanized areas and large lakes and reservoirs with elevated deposition areas, long water-retention times and high levels of anthropogenic influence. Plastic concentrations vary widely among lakes; in the most polluted, concentrations reach or even exceed those reported in the subtropical oceanic gyres, marine areas collecting large amounts of debris4. Our findings highlight the importance of including lakes and reservoirs when addressing plastic pollution, in the context of pollution management and for the continued provision of lake ecosystem services.


Assuntos
Lagos , Plásticos , Poluição da Água , Abastecimento de Água , Ecossistema , Lagos/química , Plásticos/análise , Plásticos/classificação , Poluição da Água/análise , Poluição da Água/estatística & dados numéricos , Inquéritos e Questionários , Urbanização , Atividades Humanas
3.
Proc Natl Acad Sci U S A ; 121(19): e2321024121, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38683984

RESUMO

Reconstructing the absolute chronology of Jerusalem during the time it served as the Judahite Kingdom's capital is challenging due to its dense, still inhabited urban nature and the plateau shape of the radiocarbon calibration curve during part of this period. We present 103 radiocarbon dates from reliable archaeological contexts in five excavation areas of Iron Age Jerusalem, which tie between archaeology and biblical history. We exploit Jerusalem's rich past, including textual evidence and vast archaeological remains, to overcome difficult problems in radiocarbon dating, including establishing a detailed chronology within the long-calibrated ranges of the Hallstatt Plateau and recognizing short-lived regional offsets in atmospheric 14C concentrations. The key to resolving these problems is to apply stringent field methodologies using microarchaeological methods, leading to densely radiocarbon-dated stratigraphic sequences. Using these sequences, we identify regional offsets in atmospheric 14C concentrations c. 720 BC, and in the historically secure stratigraphic horizon of the Babylonian destruction in 586 BC. The latter is verified by 100 single-ring measurements between 624 to 572 BC. This application of intense 14C dating sheds light on the reconstruction of Jerusalem in the Iron Age. It provides evidence for settlement in the 12th to 10th centuries BC and that westward expansion had already begun by the 9th century BC, with extensive architectural projects undertaken throughout the city in this period. This was followed by significant damage and rejuvenation of the city subsequent to the mid-eight century BC earthquake, after which the city was heavily fortified and continued to flourish until the Babylonian destruction.

4.
Nature ; 583(7814): 39-42, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612222

RESUMO

The interiors of giant planets remain poorly understood. Even for the planets in the Solar System, difficulties in observation lead to large uncertainties in the properties of planetary cores. Exoplanets that have undergone rare evolutionary processes provide a route to understanding planetary interiors. Planets found in and near the typically barren hot-Neptune 'desert'1,2 (a region in mass-radius space that contains few planets) have proved to be particularly valuable in this regard. These planets include HD149026b3, which is thought to have an unusually massive core, and recent discoveries such as LTT9779b4 and NGTS-4b5, on which photoevaporation has removed a substantial part of their outer atmospheres. Here we report observations of the planet TOI-849b, which has a radius smaller than Neptune's but an anomalously large mass of [Formula: see text] Earth masses and a density of [Formula: see text] grams per cubic centimetre, similar to Earth's. Interior-structure models suggest that any gaseous envelope of pure hydrogen and helium consists of no more than [Formula: see text] per cent of the total planetary mass. The planet could have been a gas giant before undergoing extreme mass loss via thermal self-disruption or giant planet collisions, or it could have avoided substantial gas accretion, perhaps through gap opening or late formation6. Although photoevaporation rates cannot account for the mass loss required to reduce a Jupiter-like gas giant, they can remove a small (a few Earth masses) hydrogen and helium envelope on timescales of several billion years, implying that any remaining atmosphere on TOI-849b is likely to be enriched by water or other volatiles from the planetary interior. We conclude that TOI-849b is the remnant core of a giant planet.

5.
Circulation ; 150(3): 190-202, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39008557

RESUMO

BACKGROUND: The interstage period after discharge from stage 1 palliation carries high morbidity and mortality. The impact of social determinants of health on interstage outcomes is not well characterized. We assessed the relationship between childhood opportunity and acute interstage outcomes. METHODS: Infants discharged home after stage 1 palliation in the National Pediatric Quality Improvement Collaborative Phase II registry (2016-2022) were retrospectively reviewed. Zip code-level Childhood Opportunity Index (COI), a composite metric of 29 indicators across education, health and environment, and socioeconomic domains, was used to classify patients into 5 COI levels. Acute interstage outcomes included death or transplant listing, unplanned readmission, intensive care unit admission, unplanned catheterization, and reoperation. The association between COI level and acute interstage outcomes was assessed using logistic regression with sequential adjustment for potential confounders. RESULTS: The analysis cohort included 1837 patients from 69 centers. Birth weight (P<0.001) and proximity to a surgical center at birth (P=0.02) increased with COI level. Stage 1 length of stay decreased (P=0.001), and exclusive oral feeding rate at discharge increased (P<0.001), with higher COI level. More than 98% of patients in all COI levels were enrolled in home monitoring. Death or transplant listing occurred in 101 (5%) patients with unplanned readmission in 987 (53%), intensive care unit admission in 448 (24%), catheterization in 345 (19%), and reoperation in 83 (5%). There was no difference in the incidence or time to occurrence of any acute interstage outcome among COI levels in unadjusted or adjusted analysis. There was no interaction between race and ethnicity and childhood opportunity in acute interstage outcomes. CONCLUSIONS: Zip code COI level is associated with differences in preoperative risk factors and stage 1 palliation hospitalization characteristics. Acute interstage outcomes, although common across the spectrum of childhood opportunity, are not associated with COI level in an era of highly prevalent home monitoring programs. The role of home monitoring in mitigating disparities during the interstage period merits further investigation.


Assuntos
Melhoria de Qualidade , Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Estudos Retrospectivos , Sistema de Registros , Cuidados Paliativos/normas , Resultado do Tratamento , Estados Unidos/epidemiologia , Determinantes Sociais da Saúde , Readmissão do Paciente , Alta do Paciente
6.
Lancet ; 403(10436): 1563-1573, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38554726

RESUMO

BACKGROUND: Frequent anti-vascular endothelial growth factor A (VEGF-A) injections reduce the risk of rapid and severe vision loss in patients with neovascular age-related macular degeneration (nAMD); however, due to undertreatment, many patients lose vision over time. New treatments that provide sustained suppression of VEGF-A are needed. RGX-314 (currently known as ABBV-RGX-314) is an adeno-associated virus serotype 8 vector that expresses an anti-VEGF-A antigen-binding fragment, which provides potential for continuous VEGF-A suppression after a single subretinal injection. We report results on the safety and efficacy of subretinal injection of RGX-314 in patients with nAMD. METHODS: For this open-label, multiple-cohort, multicentre, phase 1/2a, dose-escalation study conducted at eight sites in the USA, we enrolled participants with nAMD aged 50-89 years who had previously been treated with anti-VEGF injections into five cohorts (with five different doses of RGX-314). To be eligible, participants had to have macular neovascularisation secondary to nAMD with subretinal or intraretinal fluid in the centre subfield, be pseudophakic (after cataract removal), and have a best-corrected visual acuity (BCVA) in the study eye between 20/63 and 20/400 for the first participant in each cohort and between 20/40 and 20/400 for others. Subretinal injection of RGX-314 was done without a pre-bleb by a wet-laboratory-trained vitreoretinal surgeon. Cohort 1 received 3 × 109 genome copies per eye, cohort 2 received 1 × 1010, and cohort 3 received 6 × 1010. Two additional dose cohorts (cohort 4: 1·6 × 1011; cohort 5: 2·5 × 1011) were added. Participants were seen 1 day and 1 week after administration of RGX-314, and then monthly for 2 years (up to week 106). The primary outcome was safety of RGX-314 delivered by subretinal injection up to week 26. This analysis includes all 42 patients enrolled in the study. This study is registered with ClinicalTrials.gov, NCT03066258. FINDINGS: Between May 12, 2017, and May 21, 2019, we screened 110 patients for eligibility and enrolled 68. 42 participants demonstrated the required anatomic response to intravitreal ranibizumab and then received a single RGX-314 injection (dose range 3 × 109 to 2·5 × 1011 genome copies per eye) and were followed up for 2 years. There were 20 serious adverse events in 13 participants, of which one was possibly related to RGX-314: pigmentary changes in the macula with severe vision reduction 12 months after injection of RGX-314 at a dose of 2·5 × 1011 genome copies per eye. Asymptomatic pigmentary changes were seen in the inferior retinal periphery several months after subretinal injection of RGX-314 most commonly at doses of 6 × 1010 genome copies per eye or higher. There were no clinically determined immune responses or inflammation beyond that expected following routine vitrectomy. Doses of 6 × 1010 genome copies or higher resulted in sustained concentrations of RGX-314 protein in aqueous humour and stable or improved BCVA and central retinal thickness with few or no supplemental anti-VEGF-A injections in most participants. INTERPRETATION: Subretinal delivery of RGX-314 was generally well tolerated with no clinically recognised immune responses. RGX-314 gene therapy provides a novel approach for sustained VEGF-A suppression in patients with nAMD that has potential to control exudation, maintain vision, and reduce treatment burden after a single administration. Results from this study informed the pivotal programme to evaluate RGX-314 in patients with nAMD. FUNDING: RegenxBio.


Assuntos
Fator A de Crescimento do Endotélio Vascular , Degeneração Macular Exsudativa , Humanos , Inibidores da Angiogênese/uso terapêutico , Terapia Genética/métodos , Ranibizumab , Resultado do Tratamento , Degeneração Macular Exsudativa/tratamento farmacológico
7.
Lancet ; 403(10432): 1153-1163, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38461843

RESUMO

BACKGROUND: A high-dose formulation of intravitreal aflibercept (8 mg) could improve treatment outcomes in diabetic macular oedema (DMO) by requiring fewer injections than the standard comparator, aflibercept 2 mg. We report efficacy and safety results of aflibercept 8 mg versus 2 mg in patients with DMO. METHODS: PHOTON was a randomised, double-masked, non-inferiority, phase 2/3 trial performed at 138 hospitals and specialty retina clinics in seven countries. Eligible patients were adults aged 18 years or older with type 1 or 2 diabetes and centre-involved DMO. Patients were randomly assigned (1:2:1) to intravitreal aflibercept 2 mg every 8 weeks (2q8), aflibercept 8 mg every 12 weeks (8q12), or aflibercept 8 mg every 16 weeks (8q16), following initial monthly dosing. From week 16, dosing intervals for the aflibercept 8 mg groups were shortened if patients met prespecified dose regimen modification criteria denoting disease activity. The primary endpoint was change from baseline in best-corrected visual acuity (BCVA) at week 48 (non-inferiority margin of 4 letters). Efficacy and safety analyses included all randomly assigned patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov (NCT04429503). FINDINGS: Between June 29, 2020, and June 28, 2021, 970 patients were screened for eligibility. After exclusions, 660 patients were enrolled and randomly assigned to receive aflibercept 8q12 (n=329), 8q16 (n=164), or 2q8 (n=167); two patients were randomly assigned in error and did not receive treatment. 658 (99·7%) patients were treated and included in the full analysis set and safety analysis set (8q12 n=328, 8q16 n=163, and 2q8 n=167). Mean patient age was 62·3 years (SD 10·4). 401 (61%) patients were male. 471 (72%) patients were White. Aflibercept 8q12 and 8q16 demonstrated non-inferior BCVA gains to aflibercept 2q8 (BCVA mean change from baseline 8·8 letters [SD 9·0] in the 8q12 group, 7·9 letters [8·4] in the 8q16 group, and 9·2 letters [9·0] in the 2q8 group). The difference in least squares means was -0·57 letters (95% CI -2·26 to 1·13, p value for non-inferiority <0·0001) between 8q12 and 2q8 and -1·44 letters (-3·27 to 0·39, p value for non-inferiority 0·0031) between aflibercept 8q16 and 2q8. Proportions of patients with ocular adverse events in the study eye were similar across groups (8q12 n=104 [32%], 8q16 n=48 [29%], and 2q8 n=46 [28%]). INTERPRETATION: Aflibercept 8 mg demonstrated efficacy and safety with extended dosing intervals and could decrease treatment burden in patients with DMO. FUNDING: Regeneron Pharmaceuticals and Bayer.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Edema Macular , Adulto , Feminino , Humanos , Masculino , Inibidores da Angiogênese , Diabetes Mellitus/tratamento farmacológico , Edema Macular/etiologia , Edema Macular/induzido quimicamente , Receptores de Fatores de Crescimento do Endotélio Vascular/uso terapêutico , Proteínas Recombinantes de Fusão/efeitos adversos , Resultado do Tratamento , Pessoa de Meia-Idade , Idoso
8.
J Pathol ; 262(2): 129-136, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38013631

RESUMO

Trastuzumab has demonstrated clinical efficacy in the treatment of HER2-positive serous endometrial cancer (EC), which led to its incorporation into standard-of-care management of this aggressive disease. Acquired resistance remains an important challenge, however, and its underlying mechanisms in EC are unknown. To define the molecular changes that occur in response to anti-HER2 therapy in EC, targeted next-generation sequencing (NGS), HER2 immunohistochemistry (IHC), and fluorescence in situ hybridization (FISH) were performed on pre- and post-treatment tumour samples from 14 patients with EC treated with trastuzumab or trastuzumab emtansine. Recurrent tumours after anti-HER2 therapy acquired additional genetic alterations compared with matched pre-treatment ECs and frequently showed decreased HER2 protein expression by IHC (7/14, 50%). Complete/near-complete absence of HER2 protein expression (score 0/1+) observed post-treatment (4/14, 29%) was associated with retained HER2 gene amplification (n = 3) or copy number neutral status (n = 1). Whole-exome sequencing performed on primary and recurrent tumours from the latter case, which exhibited genetic heterogeneity of HER2 amplification in the primary tumour, revealed selection of an early HER2-non-amplified clone following therapy. Our findings demonstrate that loss of target expression, by selection of HER2-non-amplified clones or, more commonly, by downregulation of expression, may constitute a mechanism of resistance to anti-HER2 therapy in HER2-positive EC. © 2023 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Neoplasias do Endométrio , Receptor ErbB-2 , Feminino , Humanos , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Hibridização in Situ Fluorescente , Recidiva Local de Neoplasia/genética , Trastuzumab/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Amplificação de Genes
9.
J Immunol ; 211(12): 1844-1857, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37909827

RESUMO

Prior studies have defined multiple, but inconsistent, roles for the enigmatic pattern recognition receptor NLRX1 in regulating several cancer-associated biological functions. In this study, we explore the role of NLRX1 in the highly metastatic murine 4T1 mammary tumor model. We describe a functional dichotomy of NLRX1 between two different cellular contexts: expression in healthy host cells versus expression in the 4T1 tumor cells. Using Nlrx1-/- mice engrafted with 4T1 tumors, we demonstrate that NLRX1 functions as a tumor suppressor when expressed in the host cells. Specifically, NLRX1 in healthy host cells attenuates tumor growth and lung metastasis through suppressing characteristics of epithelial-mesenchymal transition and the lung metastatic niche. Conversely, we demonstrate that NLRX1 functions as a tumor promoter when expressed in 4T1 tumor cells using gain- and loss-of-function studies both in vitro and in vivo. Mechanistically, NLRX1 in the tumor cells augments 4T1 aggressiveness and metastasis through regulating epithelial-mesenchymal transition hallmarks, cell death, proliferation, migration, reactive oxygen species levels, and mitochondrial respiration. Collectively, we provide critical insight into NLRX1 function and establish a dichotomous role of NLRX1 in the 4T1 murine mammary carcinoma model that is dictated by cellular context.


Assuntos
Neoplasias Mamárias Animais , Animais , Camundongos , Linhagem Celular Tumoral , Mitocôndrias/metabolismo , Transição Epitelial-Mesenquimal , Metástase Neoplásica , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo
10.
Nature ; 567(7748): 361-365, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30894722

RESUMO

Biological organisms achieve robust high-level behaviours by combining and coordinating stochastic low-level components1-3. By contrast, most current robotic systems comprise either monolithic mechanisms4,5 or modular units with coordinated motions6,7. Such robots require explicit control of individual components to perform specific functions, and the failure of one component typically renders the entire robot inoperable. Here we demonstrate a robotic system whose overall behaviour can be successfully controlled by exploiting statistical mechanics phenomena. We achieve this by incorporating many loosely coupled 'particles', which are incapable of independent locomotion and do not possess individual identity or addressable position. In the proposed system, each particle is permitted to perform only uniform volumetric oscillations that are phase-modulated by a global signal. Despite the stochastic motion of the robot and lack of direct control of its individual components, we demonstrate physical robots composed of up to two dozen particles and simulated robots with up to 100,000 particles capable of robust locomotion, object transport and phototaxis (movement towards a light stimulus). Locomotion is maintained even when 20 per cent of the particles malfunction. These findings indicate that stochastic systems may offer an alternative approach to more complex and exacting robots via large-scale robust amorphous robotic systems that exhibit deterministic behaviour.

11.
Annu Rev Physiol ; 83: 127-151, 2021 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-33228454

RESUMO

GDF15 is a cell activation and stress response cytokine of the glial cell line-derived neurotrophic factor family within the TGF-ß superfamily. It acts through a recently identified orphan member of the GFRα family called GFRAL and signals through the Ret coreceptor. Cell stress and disease lead to elevated GDF15 serum levels, causing anorexia, weight loss, and alterations to metabolism, largely by actions on regions of the hindbrain. These changes restore homeostasis and, in the case of obesity, cause a reduction in adiposity. In some diseases, such as advanced cancer, serum GDF15 levels can rise by as much as 10-100-fold, leading to an anorexia-cachexia syndrome, which is often fatal. This review discusses how GDF15 regulates appetite and metabolism, the role it plays in resistance to obesity, and how this impacts diseases such as diabetes, nonalcoholic fatty liver disease, and anorexia-cachexia syndrome. It also discusses potential therapeutic applications of targeting the GDF15-GFRAL pathway and lastly suggests some potential unifying hypotheses for its biological role.


Assuntos
Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Fator 15 de Diferenciação de Crescimento/metabolismo , Doenças Metabólicas/metabolismo , Transdução de Sinais/fisiologia , Animais , Humanos
12.
Prostate ; 84(8): 747-755, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38544345

RESUMO

BACKGROUND: Elevated circulating growth differentiation factor (GDF15/MIC-1), interleukin 4 (IL4), and IL6 levels were associated with resistance to docetaxel in an exploratory cohort of men with metastatic castration-resistant prostate cancer (mCRPC). This study aimed to establish level 2 evidence of cytokine biomarker utility in mCRPC. METHODS: IntVal: Plasma samples at baseline (BL) and Day 21 docetaxel (n = 120). ExtVal: Serum samples at BL and Day 42 of docetaxel (n = 430). IL4, IL6, and GDF15 levels were measured by ELISA. Monocytes and dendritic cells were treated with 10% plasma from men with high or low GDF15 or recombinant GDF15. RESULTS: IntVal: Higher GDF15 levels at BL and Day 21 were associated with shorter overall survival (OS) (BL; p = 0.03 and Day 21; p = 0.004). IL4 and IL6 were not associated with outcomes. ExtVal: Higher GDF15 levels at BL and Day 42 predicted shorter OS (BL; p < 0.0001 and Day 42; p < 0.0001). Plasma from men with high GDF15 caused an increase in CD86 expression on monocytes (p = 0.03), but was not replicated by recombinant GDF15. CONCLUSIONS: Elevated circulating GDF15 is associated with poor prognosis in men with mCRPC receiving docetaxel and may be a marker of changes in the innate immune system in response to docetaxel resistance. These findings provide a strong rationale to consider GDF15 as a biomarker to guide a therapeutic trial of drugs targeting the innate immune system in combination with docetaxel in mCRPC.


Assuntos
Antineoplásicos , Biomarcadores Tumorais , Docetaxel , Fator 15 de Diferenciação de Crescimento , Neoplasias de Próstata Resistentes à Castração , Humanos , Masculino , Fator 15 de Diferenciação de Crescimento/sangue , Docetaxel/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/mortalidade , Biomarcadores Tumorais/sangue , Idoso , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Pessoa de Meia-Idade , Interleucina-4/sangue , Interleucina-6/sangue , Resistencia a Medicamentos Antineoplásicos , Monócitos/patologia , Monócitos/efeitos dos fármacos
13.
J Neuroinflammation ; 21(1): 63, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429643

RESUMO

Next-generation humanised mouse models and single-cell RNA sequencing (scRNAseq) approaches enable in-depth studies into human immune cell biology. Here we used NSG-SGM3 mice engrafted with human umbilical cord haematopoietic stem cells to investigate how human immune cells respond to and/or are changed by traumatic spinal cord injury (SCI). We hypothesised that the use of such mice could help advance our understanding of spinal cord injury-induced immune depression syndrome (SCI-IDS), and also how human leukocytes change as they migrate from the circulation into the lesion site. Our scRNAseq experiments, supplemented by flow cytometry, demonstrate the existence of up to 11 human immune cell (sub-) types and/or states across the blood and injured spinal cord (7 days post-SCI) of humanised NSG-SGM3 mice. Further comparisons of human immune cell transcriptomes between naïve, sham-operated and SCI mice identified a total of 579 differentially expressed genes, 190 of which were 'SCI-specific' (that is, genes regulated only in response to SCI but not sham surgery). Gene ontology analysis showed a prominent downregulation of immune cell function under SCI conditions, including for T cell receptor signalling and antigen presentation, confirming the presence of SCI-IDS and the transcriptional signature of human leukocytes in association with this phenomenon. We also highlight the activating influence of the local spinal cord lesion microenvironment by comparing the transcriptomes of circulating versus infiltrated human immune cells; those isolated from the lesion site were enriched for genes relating to both immune cell activity and function (e.g., oxidative phosphorylation, T cell proliferation and antigen presentation). We lastly applied an integrated bioinformatics approach to determine where immune responses in humanised NSG-SGM3 mice appear congruent to the native responses of human SCI patients, and where they diverge. Collectively, our study provides a valuable resource and methodological framework for the use of these mice in translational research.


Assuntos
Doenças da Medula Espinal , Traumatismos da Medula Espinal , Camundongos , Humanos , Animais , Traumatismos da Medula Espinal/metabolismo , Leucócitos/patologia , Expressão Gênica , Análise de Sequência de RNA
14.
J Antimicrob Chemother ; 79(5): 1006-1013, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38497988

RESUMO

BACKGROUND: Antimicrobial resistance in Neisseria gonorrhoeae is threatening the gonorrhoea treatment, and optimizations of the current ceftriaxone-treatment regimens are crucial. We evaluated the pharmacodynamics of ceftriaxone single-dose therapy (0.125-1 g) against ceftriaxone-susceptible and ceftriaxone-resistant gonococcal strains, based on EUCAST ceftriaxone-resistance breakpoint (MIC > 0.125 mg/L), in our hollow fibre infection model (HFIM) for gonorrhoea. METHODS: Gonococcal strains examined were WHO F (ceftriaxone-susceptible, MIC < 0.002 mg/L), R (ceftriaxone-resistant, MIC = 0.5 mg/L), Z (ceftriaxone-resistant, MIC = 0.5 mg/L) and X (ceftriaxone-resistant, MIC = 2 mg/L). Dose-range HFIM 7 day experiments simulating ceftriaxone 0.125-1 g single-dose intramuscular regimens were conducted. RESULTS: Ceftriaxone 0.125-1 g single-dose treatments rapidly eradicated WHO F (wild-type ceftriaxone MIC). Ceftriaxone 0.5 and 1 g treatments, based on ceftriaxone human plasma pharmacokinetic parameters, eradicated most ceftriaxone-resistant gonococcal strains (WHO R and Z), but ceftriaxone 0.5 g failed to eradicate WHO X (high-level ceftriaxone resistance). When simulating oropharyngeal gonorrhoea, ceftriaxone 0.5 g failed to eradicate all the ceftriaxone-resistant strains, while ceftriaxone 1 g eradicated WHO R and Z (low-level ceftriaxone resistance) but failed to eradicate WHO X (high-level ceftriaxone resistance). No ceftriaxone-resistant mutants were selected using any ceftriaxone treatments. CONCLUSIONS: Ceftriaxone 1 g single-dose intramuscularly cure most of the anogenital and oropharyngeal gonorrhoea cases caused by the currently internationally spreading ceftriaxone-resistant gonococcal strains, which should be further confirmed clinically. A ceftriaxone 1 g dose (±azithromycin 2 g) should be recommended for first-line empiric gonorrhoea treatment. This will buy countries some time until novel antimicrobials are licensed. Using ceftriaxone 1 g gonorrhoea treatment, the EUCAST ceftriaxone-resistance breakpoint is too low.


Assuntos
Antibacterianos , Ceftriaxona , Gonorreia , Testes de Sensibilidade Microbiana , Neisseria gonorrhoeae , Ceftriaxona/farmacocinética , Ceftriaxona/farmacologia , Ceftriaxona/administração & dosagem , Neisseria gonorrhoeae/efeitos dos fármacos , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Antibacterianos/administração & dosagem , Gonorreia/tratamento farmacológico , Gonorreia/microbiologia , Humanos , Farmacorresistência Bacteriana
15.
Mod Pathol ; 37(2): 100375, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37925055

RESUMO

CDH1 encodes for E-cadherin, and its loss of function is the hallmark of invasive lobular carcinoma (ILC). Albeit vanishingly rare, biallelic CDH1 alterations may be found in nonlobular breast carcinomas (NL-BCs). We sought to determine the clinicopathologic characteristics and repertoire of genetic alterations of NL-BCs harboring CDH1 biallelic genetic alterations. Analysis of 5842 breast cancers (BCs) subjected to clinical tumor-normal sequencing with an FDA-cleared multigene panel was conducted to identify BCs with biallelic CDH1 pathogenic/likely pathogenic somatic mutations lacking lobular features. The genomic profiles of NL-BCs with CDH1 biallelic genetic alterations were compared with those of ILCs and invasive ductal carcinomas (IDCs), matched by clinicopathologic characteristics. Of the 896 CDH1-altered BCs, 889 samples were excluded based on the diagnosis of invasive mixed ductal/lobular carcinoma or ILC or the detection of monoallelic CDH1 alterations. Only 7 of the 5842 (0.11%) BCs harbored biallelic CDH1 alterations and lacked lobular features. Of these, 4/7 (57%) cases were ER-positive/HER2-negative, 1/7 (14%) was ER-positive/HER2-positive, and 2/7 (29%) were ER-negative/HER2-negative. In total, 5/7 (71%) were of Nottingham grade 2, and 2/7 (29%) were of grade 3. The NL-BCs with CDH1 biallelic genetic alterations included a mucinous carcinoma (n = 1), IDCs with focal nested growth (n = 2), IDC with solid papillary (n = 1) or apocrine (n = 2) features, and an IDC of no special type (NST; n = 1). E-cadherin expression, as detected by immunohistochemistry, was absent (3/5) or aberrant (discontinuous membranous/cytoplasmic/granular; 2/5). However, NL-BCs with CDH1 biallelic genetic alterations displayed recurrent genetic alterations, including TP53, PIK3CA (57%, 4/7; each), FGFR1, and NCOR1 (28%, 2/7, each) alterations. Compared with CDH1 wild-type IDC-NSTs, NL-BCs less frequently harbored GATA3 mutations (0% vs 47%, P = .03), but no significant differences were detected when compared with matched ILCs. Therefore, NL-BCs with CDH1 biallelic genetic alterations are vanishingly rare, predominantly comprise IDCs with special histologic features, and have genomic features akin to luminal B ER-positive BCs.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Lobular , Humanos , Feminino , Carcinoma Lobular/patologia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Caderinas/genética , Genômica , Antígenos CD/genética
16.
Brain Behav Immun ; 115: 191-200, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37848096

RESUMO

BACKGROUND: Clinical trials of anti-inflammatories in schizophrenia do not show clear and replicable benefits, possibly because patients were not recruited based on elevated inflammation status. Interleukin 1-beta (IL-1ß) mRNA and protein levels are increased in serum, plasma, cerebrospinal fluid, and brain of some chronically ill patients with schizophrenia, first episode psychosis, and clinical high-risk individuals. Canakinumab, an approved anti-IL-1ß monoclonal antibody, interferes with the bioactivity of IL-1ß and interrupts downstream signaling. However, the extent to which canakinumab reduces peripheral inflammation markers, such as, high sensitivity C-reactive protein (hsCRP) and symptom severity in schizophrenia patients with inflammation is unknown. TRIAL DESIGN: We conducted a randomized, placebo-controlled, double-blind, parallel groups, 8-week trial of canakinumab in chronically ill patients with schizophrenia who had elevated peripheral inflammation. METHODS: Twenty-seven patients with schizophrenia or schizoaffective disorder and elevated peripheral inflammation markers (IL-1ß, IL-6, hsCRP and/or neutrophil to lymphocyte ratio: NLR) were randomized to a one-time, subcutaneous injection of canakinumab (150 mg) or placebo (normal saline) as an adjunctive antipsychotic treatment. Peripheral blood hsCRP, NLR, IL-1ß, IL-6, IL-8 levels were measured at baseline (pre injection) and at 1-, 4- and 8-weeks post injection. Symptom severity was assessed at baseline and 4- and 8-weeks post injection. RESULTS: Canakinumab significantly reduced peripheral hsCRP over time, F(3, 75) = 5.16, p = 0.003. Significant hsCRP reductions relative to baseline were detected only in the canakinumab group at weeks 1, 4 and 8 (p's = 0.0003, 0.000002, and 0.004, respectively). There were no significant hsCRP changes in the placebo group. Positive symptom severity scores were significantly reduced at week 8 (p = 0.02) in the canakinumab group and week 4 (p = 0.02) in the placebo group. The change in CRP between week 8 and baseline (b = 1.9, p = 0.0002) and between week 4 and baseline (b = 6.0, p = 0.001) were highly significant predictors of week 8 change in PANSS Positive Symptom severity scores. There were no significant changes in negative symptoms, general psychopathology or cognition in either group. Canakinumab was well tolerated and only 7 % discontinued. CONCLUSIONS: Canakinumab quickly reduces peripheral hsCRP serum levels in patients with schizophrenia and inflammation; after 8 weeks of canakinumab treatment, the reductions in hsCRP are related to reduced positive symptom severity. Future studies should consider increased doses or longer-term treatment to confirm the potential benefits of adjunctive canakinumab in schizophrenia. Australian and New Zealand Clinical Trials Registry number: ACTRN12615000635561.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/tratamento farmacológico , Proteína C-Reativa/análise , Anticorpos Monoclonais/uso terapêutico , Interleucina-6 , Austrália , Inflamação/tratamento farmacológico , Doença Crônica , Método Duplo-Cego , Resultado do Tratamento
17.
Environ Res ; 252(Pt 3): 119014, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38685296

RESUMO

In 2014, a fire at an open cut coalmine in regional Victoria, Australia burned for 6 weeks. Residents of the nearby town of Morwell were exposed to smoke, which included high levels of fine particulate matter (PM2.5). We investigated whether the long-term effects of PM2.5 on respiratory health were moderated by diet quality. A cross-sectional analysis was conducted of data collected 8.5 years after the mine fire from 282 residents of Morwell and 166 residents from the nearby unexposed town of Sale. Primary outcomes were respiratory symptoms. Exposure was coalmine fire-related PM2.5 and diet quality was assessed as Australian Recommended Food Score (ARFS) derived using the Australian Eating Survey (AES). The moderating effect of diet quality on respiratory outcomes associated with PM2.5 was assessed using logistic regression models, adjusting for potential confounders. Diet quality was poor in this sample, with 60% in the lowest category of overall diet quality. Overall diet quality and fruit and vegetable quality significantly attenuated the association between PM2.5 and prevalence of chronic cough and phlegm. Sauce/condiment intake was associated with a greater effect of PM2.5 on COPD prevalence. No other moderating effects were significant. The moderating effects of overall diet quality and vegetable and fruit intake aligned with a priori hypotheses, suggesting potential protective benefits. While more evidence is needed to confirm these findings, improving diets, especially fruit and vegetable intake, may provide some protection against the effects of smoke exposure from fire events.


Assuntos
Dieta , Material Particulado , Humanos , Material Particulado/análise , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Transversais , Vitória/epidemiologia , Idoso , Adulto , Incêndios , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Exposição Ambiental/efeitos adversos , Minas de Carvão , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/induzido quimicamente
18.
Respirology ; 29(1): 56-62, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37681548

RESUMO

BACKGROUND: In 2014, the Hazelwood coalmine fire shrouded the regional Australian town of Morwell in smoke and ash for 6 weeks. One of the fire's by-products, PM2.5 , is associated with an increased risk of COVID-19 and severe disease. However, it is unclear whether the effect persisted for years after exposure. In this study, we surveyed a cohort established prior to the pandemic to determine whether PM2.5 from the coalmine fire increased long-term vulnerability to COVID-19 and severe disease. METHODS: From August to December 2022, 612 members of the Hazelwood Health Study's adult cohort, established in 2016/17, participated in a follow-up survey that included standardized items to capture COVID-19 cases, as well as questions about hospitalization and vaccinations. Associations were evaluated in crude and adjusted logistic regression models. RESULTS: A total of 268 (44%) participants self-reported or met symptom criteria for having had COVID-19 at least once. All models found a positive association, with odds of COVID-19 increasing by between 4% and 30% for a 10 µg/m3 increase in coalmine fire-related PM2.5 exposure. However, the association was significant in only 2 of the 18 models. There were insufficient hospitalizations to examine severity (n = 7; 1%). CONCLUSION: The findings are inconclusive on the effect of coalmine fire-related PM2.5 exposure on long-term vulnerability to COVID-19. Given the positive association that was robust to modelling variations as well as evidence for a causal mechanism, it would be prudent to treat PM2.5 from fire events as a long-term risk factor until more evidence accumulates.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , COVID-19 , Adulto , Humanos , Material Particulado/efeitos adversos , Material Particulado/análise , Poluentes Atmosféricos/efeitos adversos , Estudos de Coortes , Austrália/epidemiologia , COVID-19/epidemiologia , Fumaça/efeitos adversos , Exposição Ambiental/efeitos adversos , Poluição do Ar/efeitos adversos
19.
Retina ; 44(7): 1165-1170, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38900578

RESUMO

BACKGROUND/PURPOSE: To determine and compare the efficacy of a surgical internal limiting membrane (ILM) flap technique with the traditional ILM peel on long-term visual and anatomical outcomes for large (>400 µm) full-thickness macular holes. METHODS: From October 2016 to July 2022, patients undergoing initial full-thickness macular hole repair with the ILM flap or ILM peel technique were reviewed. Final outcomes were recorded and based on size in microns: 401 to 800, 801 to 1,200, and >1,200. RESULTS: Patients treated with ILM flap (n = 52, 94.2% closure rate) or ILM peel (n = 407, 93.6% closure rate) were followed with a mean follow-up time of 15.0 ± 10.2 and 20.0 ± 13.4 months, respectively. Success rates for ILM flaps and ILM peels were compared for full-thickness macular holes of 401 to 800 (100%, 95.8%, P = 0.39), 801 to 1,200 (95%, 93%, P = 0.74), and >1,200 (86.7%, 86.7%, P = 1.0) µm. Mean best-recorded logarithm of the minimal angle of resolution visual acuity for ILM flaps and ILM peels, respectively, was 1.02 ± 0.46 and 0.87 ± 0.47 preoperatively, with follow-up acuity of 0.48 ± 0.32 (P < 0.03) and 0.39 ± 0.42 (P < 0.01) at Year 3. CONCLUSION: Both techniques provide a similar anatomical closure rate and functional improvement in vision. Comparisons should be cautiously made based on difference in preoperative hole size.


Assuntos
Membrana Basal , Perfurações Retinianas , Retalhos Cirúrgicos , Tomografia de Coerência Óptica , Acuidade Visual , Vitrectomia , Humanos , Perfurações Retinianas/cirurgia , Perfurações Retinianas/fisiopatologia , Feminino , Membrana Basal/cirurgia , Masculino , Acuidade Visual/fisiologia , Vitrectomia/métodos , Estudos Retrospectivos , Idoso , Seguimentos , Pessoa de Meia-Idade , Resultado do Tratamento , Tamponamento Interno/métodos , Fatores de Tempo , Membrana Epirretiniana/cirurgia
20.
Retina ; 44(6): 939-949, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38451179

RESUMO

PURPOSE: To develop professional guidelines for best practices for suprachoroidal space (SCS) injection, an innovative technique for retinal therapeutic delivery, based on current published evidence and clinical experience. METHODS: A panel of expert ophthalmologists reviewed current published evidence and clinical experience during a live working group meeting to define points of consensus and key clinical considerations to inform the development of guidelines for in-office SCS injection. RESULTS: Core consensus guidelines for in-office SCS injection were reached and reported by the expert panel. Current clinical evidence and physician experience supported SCS injection as a safe and effective method for delivering retinal and choroidal therapeutics. The panel established consensus on the rationale for SCS injection, including potential benefits relative to other intraocular delivery methods and current best practices in patient preparation, pre- and peri-injection management, SCS-specific injection techniques, and postinjection management and follow-up. CONCLUSION: These expert panel guidelines may support and promote standardization of SCS injection technique, with the goal of optimizing patient safety and outcomes. Some aspects of the procedure may reasonably be modified based on the clinical setting and physician judgment, as well as additional study.


Assuntos
Corioide , Humanos , Injeções Intraoculares , Doenças Retinianas , Guias de Prática Clínica como Assunto
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