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BACKGROUND: Advances in pediatric oncology have occurred for some cancers; however, new therapies for sarcoma have been inadequate. Cellular immunotherapy using chimeric antigen receptor (CAR) T cells has shown dramatic benefits in leukemia, lymphoma, and multiple myeloma but has been far less successful in pediatric solid tumors such as rhabdomyosarcoma (RMS) and osteosarcoma (OS). Balancing issues of "on-target, off-tumor toxicity", investigators have identified B7-H3 as a broadly expressed tumor antigen with otherwise restricted expression on normal tissues. We hypothesized that rapid homing via a chemokine receptor and CAR engagement through B7-H3 would enhance CAR T cell efficacy in solid tumors. METHODS: We generated B7-H3 CAR T cells that also express the Interleukin-8 (IL-8) receptor, CXCR2. Cytokine production, flow cytometry, Seahorse assays and RNA sequencing were used to compare the B7-H3 CXCR2 (BC2) CAR T cells with B7-H3 CAR T cells. We developed an IL-8 overexpressing human RMS mouse model to test homing and cytotoxicity in vivo. RESULTS: We demonstrate that IL-8 is expressed by RMS and OS and expression significantly increases after radiation. Overexpression of an IL-8 receptor, CXCR2, on B7-H3 CAR T cells enhances homing into IL-8 expressing tumors, augments T cell metabolism and leads to significant tumor regression. CONCLUSION: These findings warrant further investigation into the use of BC2 CAR T cells as a treatment for patients with RMS, OS and other B7-H3-expressing, IL-8 producing solid tumors.
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Antígenos B7 , Interleucina-8 , Receptores de Antígenos Quiméricos , Humanos , Animais , Camundongos , Antígenos B7/metabolismo , Interleucina-8/metabolismo , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/metabolismo , Imunoterapia Adotiva/métodos , Sarcoma/terapia , Sarcoma/imunologia , Linhagem Celular Tumoral , Criança , Linfócitos T/imunologia , Linfócitos T/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Ocean acidification (OA) is known to influence biological and ecological processes, mainly focusing on its impacts on single species, but little has been documented on how OA may alter plankton community interactions. Here, we conducted a mesocosm experiment with ambient (â¼410 ppmv) and high (1000 ppmv) CO2 concentrations in a subtropical eutrophic region of the East China Sea and examined the community dynamics of microeukaryotes, bacterioplankton and microeukaryote-attached bacteria in the enclosed coastal seawater. The OA treatment with elevated CO2 affected taxa as the phytoplankton bloom stages progressed, with a 72.89% decrease in relative abundance of the protist Cercozoa on day 10 and a 322% increase in relative abundance of Stramenopile dominated by diatoms, accompanied by a 29.54% decrease in relative abundance of attached Alphaproteobacteria on day 28. Our study revealed that protozoans with different prey preferences had differing sensitivity to high CO2, and attached bacteria were more significantly affected by high CO2 compared to bacterioplankton. Our findings indicate that high CO2 changed the co-occurrence network complexity and stability of microeukaryotes more than those of bacteria. Furthermore, high CO2 was found to alter the proportions of potential interactions between phytoplankton and their predators, as well as microeukaryotes and their attached bacteria in the networks. The changes in the relative abundances and interactions of microeukaryotes between their predators in response to high CO2 revealed in our study suggest that high CO2 may have profound impacts on marine food webs.
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Dióxido de Carbono , Eutrofização , Cadeia Alimentar , Água do Mar , Água do Mar/química , Dióxido de Carbono/análise , Fitoplâncton/efeitos dos fármacos , Bactérias , Concentração de Íons de Hidrogênio , Oceanos e Mares , China , Plâncton , Acidificação dos OceanosRESUMO
OBJECTIVE: Little is known about how the COVID-19 pandemic affected cancer screenings among American Indian people residing in California and Oklahoma, 2 states with the largest American Indian populations. We assessed rates and factors associated with cancer screenings among American Indian adults during the pandemic. METHODS: From October 2020 through January 2021, we surveyed 767 American Indian adults residing in California and Oklahoma. We asked participants whether they had planned to obtain screenings for breast cancer, cervical cancer, and colorectal cancer (CRC) from March through December 2020 and whether screening was postponed because of COVID-19. We calculated adjusted odds ratios (AORs) for factors associated with reasons for planned and postponed cancer screening. RESULTS: Among 395 participants eligible for breast cancer screening, 234 (59.2%) planned to obtain the screening, 127 (54.3%) of whom postponed it. Among 517 participants eligible for cervical cancer screening, 357 (69.1%) planned to obtain the screening, 115 (32.2%) of whom postponed it. Among 454 participants eligible for CRC screening, 282 (62.1%) planned to obtain CRC screening, 80 of whom (28.4%) postponed it. In multivariate analyses, women who lived with a child (vs did not) had lower odds of planning to obtain a breast cancer screening (AOR = 0.6; 95% CI, 0.3-1.0). Adherence to social distancing recommendations was associated with planning to have and postponement of cervical cancer screening (AOR = 7.3; 95% CI, 0.9-58.9). Participants who received (vs did not receive) social or financial support had higher odds of planning to have CRC screening (AOR = 2.0; 95% CI, 1.1-3.9). CONCLUSION: The COVID-19 pandemic impeded completion of cancer screenings among American Indian adults. Interventions are needed to increase the intent to receive evidence-based cancer screenings among eligible American Indian adults.
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Background: This study explored the increased quantity and frequency of alcohol use in the American Indian (AI) population during the COVID-19 pandemic.Objectives: The aims of this study were to explore possible associations between covariables and both binge drinking and alcohol consumption during COVID-19.Methods: This cross-sectional survey study analyzed data from a sample of AI individuals (63% female) residing in California (n = 411) and Oklahoma (n = 657) between October 2020-January 2021. Analysis included summary statistics and multivariable logistic regression, including a variety of socio-economic, COVID-19 concern, and tobacco and marijuana use variables.Results: One or more alcohol binge episodes were reported between October 2020-January 2021 in 19.3% of participants and elevated overall alcohol consumption was reported by 21.6% of participants. Higher odds of elevated alcohol consumption occurred in women and those following more social distancing measures. The odds of binge drinking or elevated alcohol consumption in those using both marijuana and tobacco (aOR/ adjusted odds ratio:18.9, 95% CI = 8.5, 42.2, and aOR:3.9, 95% CI = 1.7, 8.6, respectively) were higher compared to those using neither. Similarly, the odds of binge drinking or elevated alcohol consumption in those using tobacco only (aOR:4.7, 95% CI = 2.9, 7.7 and aOR: 2.0, 95% CI = 1.1, 3.5, respectively) were higher compared to those using neither.Conclusions: This study found high rates of alcohol use and bingeing during the COVID-19 pandemic. Offering collaborative, culturally sensitive, and affordable support services are important components of intervention and preparation for future stressful events on local, as well as global levels.
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Consumo de Bebidas Alcoólicas , Consumo Excessivo de Bebidas Alcoólicas , COVID-19 , Humanos , Feminino , COVID-19/epidemiologia , Consumo Excessivo de Bebidas Alcoólicas/epidemiologia , Masculino , Oklahoma/epidemiologia , Estudos Transversais , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , California/epidemiologia , Pessoa de Meia-Idade , Adulto Jovem , Adolescente , Indígenas Norte-Americanos/estatística & dados numéricos , Indígena Americano ou Nativo do Alasca/estatística & dados numéricos , IdosoRESUMO
Blooms of microalgal red tides and macroalgae (e.g., green and golden tides caused by Ulva and Sargassum) have caused widespread problems around China in recent years, but there is uncertainty around what triggers these blooms and how they interact. Here, we use 30 years of monitoring data to help answer these questions, focusing on the four main species of microalgae Prorocentrum donghaiense, Karenia mikimotoi, Noctiluca scintillans, and Skeletonema costatum) associated with red tides in the region. The frequency of red tides increased from 1991 to 2003 and then decreased until 2020, with S. costatum red tides exhibiting the highest rate of decrease. Green tides started to occur around China in 1999 and the frequency of green tides has since been on the increase. Golden tides were first reported to occur around China in 2012. The frequency of macroalgal blooms has a negative linear relationship with the frequency and coverage of red tides around China, and a positive correlation with total nitrogen and phosphorus loads as well as with atmospheric CO2 and sea surface temperature (SST). Increased outbreaks of macroalgal blooms are very likely due to worsening levels of eutrophication, combined with rising CO2 and SST, which contribute to the reduced frequency of red tides. The increasing grazing rate of microzooplankton also results in the decline in areas affected by red tides. This study shows a clear shift of algal blooms from microalgae to macroalgae around China over the past 30 years driven by the combination of eutrophication, climate change, and grazing stress, indicating a fundamental change in coastal systems in the region.
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Dinoflagellida , Microalgas , Alga Marinha , Mudança Climática , Dióxido de Carbono , Eutrofização , ChinaRESUMO
Human activities simultaneously alter nutrient levels, habitat structure, and levels of parasitism. These activities likely have individual and joint impacts on food webs. Furthermore, there is particular concern that nutrient additions and changes to habitat structure might exacerbate the size of epidemics and impacts on host density. We used a well-studied zooplankton-fungus host-parasite system and experimental whole water column enclosures to factorially manipulate nutrient levels, habitat structure (specifically: mixing), and presence of parasites. Nutrient addition increased infection prevalence, density of infected hosts, and total host density. We hypothesized that nutrients, mixing, and parasitism were linked in multiple ways, including via their combined effects on phytoplankton (resource) abundance, and we used structural equation modeling to disentangle these pathways. In the absence of the parasite, both nutrients and mixing increased abundance of phytoplankton, whereas host density was negatively related to phytoplankton abundance, suggesting a mixture of bottom-up and top-down control of phytoplankton. In the presence of the parasite, nutrients still increased phytoplankton abundance but mixing no longer did, and there was no longer a significant relationship between host density and phytoplankton. This decoupling of host-resource dynamics may have resulted from reduced grazing due to illness-mediated changes in feeding behavior. Overall, our results show that the impact of one human activity (e.g., altered habitat structure) might depend on other human impacts (e.g., parasite introduction). Fortunately, carefully designed experiments and analyses can help tease apart these multifaceted relationships, allowing us to understand how human activities alter food webs, including interactions between hosts and their parasites and resources.
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Ecossistema , Parasitos , Animais , Humanos , Cadeia Alimentar , Fitoplâncton , NutrientesRESUMO
INTRODUCTION: American Indian (AI) people experience a disproportionate tobacco and marijuana burden which may have been exacerbated by the COVID-19 pandemic. Little is known about the tobacco and marijuana habits of American Indian individuals during the COVID-19 pandemic. The objective of this study is to examine tobacco and marijuana use as well as change in use during the COVID-19 pandemic among the American Indian community. METHODS: This cross-sectional study analyzes survey data from a convenience sample of American Indian individuals residing in California and Oklahoma and included adults with and without cancer that resided in both rural and urban areas (n=1068). RESULTS: During October 2020 - January 2021, 36.0% of participants reported current use of tobacco products, 9.9% reported current use of marijuana products, and 23.7% reported increased use of tobacco and/or marijuana in the past 30 days, with no difference between those with cancer and those without cancer. Tobacco use was associated with marital status, age, employment status, COVID-19 exposure, COVID-19 beliefs, and alcohol consumption. Marijuana use was associated with COVID-19 beliefs, alcohol consumption, and income level. Increased tobacco and/or marijuana use was associated with baseline use of those products. Nearly a quarter of participants reported increased use of tobacco and/or marijuana products during the COVID-19 pandemic. CONCLUSIONS: We observed high rates of tobacco use during the COVID-19 pandemic, consistent with other studies. Research is needed to examine whether tobacco and marijuana use will decrease to pre-pandemic levels post-pandemic or if these behaviors will persist post-pandemic. Given these findings, there is a pressing need to increase access to evidence-based tobacco and marijuana treatment services in the AI population post COVID-19 pandemic.
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Objectives: Assess the percentage of cancer-related appointment delays, cancelations, and the unavailability of medications experienced by American Indian participants during the COVID-19 pandemic. Methods: This cross-sectional survey study was completed between October 2020 and July 2021 by 360 individuals with cancer who lived in California and Oklahoma. Binary and multivariate logistic regression analysis was completed in SAS 9.4. Results: During the initial Covid-19 pandemic, almost one-third (30%) of respondents delayed cancer-related appointments, 42% canceled cancer-related appointments, and one-quarter (24%) were unable to access prescription medications or over-the-counter medications (27%) due to COVID-19. People who underwent testing for COVID-19 were five times more likely to delay a medical appointment [adjusted odds ratio (aOR) = 5.3, 95% CI:2.4, 11.7] and people who followed three or more social distancing measures were more than six times more likely to cancel medical appointments (aOR:6.3, 95% CI:2.9, 13.9). Conclusion: This study identifies delays, cancelations, and medication inaccessibility people identifying as American Indian faced during the coronavirus pandemic. Disparities in healthcare delivery could contribute to increased morbidity and mortality rates of cancer.
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COVID-19 , Neoplasias , Aceitação pelo Paciente de Cuidados de Saúde , Humanos , Indígena Americano ou Nativo do Alasca , COVID-19/epidemiologia , Estudos Transversais , Neoplasias/terapia , PandemiasRESUMO
Transforming growth factor beta (TGFß) activity is linked to metastasis in many cancer types, but whether TGFß activity is necessary for squamous cell carcinoma (SCC) lung metastasis has not been studied. Here we used a lung metastatic SCC model derived from keratin 15 (K15). KrasG12D.Smad4-/- SCC and human SCC specimens to identify metastasis drivers and test therapeutic interventions. We demonstrated that a TGFß receptor (TGFßR) inhibitor reduced lung metastasis in mouse SCC correlating with reduced CD11b+/Ly6G+ myeloid cells positive for inducible nitric oxide synthase (iNOS). Further, TGFß activity and iNOS were higher in primary human oral SCCs with metastasis than SCCs without metastasis. Consistently, either depleting myeloid cells with anti-Gr1 antibody or inhibiting iNOS with L-N6-(1-iminoethyl)-l-lysine (L-NIL) reduced SCC lung metastasis. L-NIL treated tumor-bearing mice exhibited reductions in tumor-infiltrating myeloid cells and in plasma Cxcl5 levels, and attenuated primary tumor growth with increased apoptosis and decreased proliferation. Blocking Cxcl5 with an antagonist of its receptor Cxcr2, SB225002, also reduced SCC lung metastasis.
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Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Camundongos , Animais , Óxido Nítrico Sintase Tipo II , Fator de Crescimento Transformador beta/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/metabolismo , Células Mieloides/metabolismo , Óxido Nítrico/metabolismoRESUMO
Global marine conservation remains fractured by an imbalance in research efforts and policy actions, limiting progression towards sustainability. Rhodolith beds represent a prime example, as they have ecological importance on a global scale, provide a wealth of ecosystem functions and services, including biodiversity provision and potential climate change mitigation, but remain disproportionately understudied, compared to other coastal ecosystems (tropical coral reefs, kelp forests, mangroves, seagrasses). Although rhodolith beds have gained some recognition, as important and sensitive habitats at national/regional levels during the last decade, there is still a notable lack of information and, consequently, specific conservation efforts. We argue that the lack of information about these habitats, and the significant ecosystem services they provide, is hindering the development of effective conservation measures and limiting wider marine conservation success. This is becoming a pressing issue, considering the multiple severe pressures and threats these habitats are exposed to (e.g., pollution, fishing activities, climate change), which may lead to an erosion of their ecological function and ecosystem services. By synthesizing the current knowledge, we provide arguments to highlight the importance and urgency of levelling-up research efforts focused on rhodolith beds, combating rhodolith bed degradation and avoiding the loss of associated biodiversity, thus ensuring the sustainability of future conservation programs.
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Biodiversidade , Ecossistema , Recifes de Corais , Poluição Ambiental , Florestas , Conservação dos Recursos NaturaisRESUMO
The healthy herds hypothesis proposes that predators can reduce parasite prevalence and thereby increase the density of their prey. However, evidence for such predator-driven reductions in the prevalence of prey remains mixed. Furthermore, even less evidence supports increases in prey density during epidemics. Here, we used a planktonic predator-prey-parasite system to experimentally test the healthy herds hypothesis. We manipulated density of a predator (the phantom midge, Chaoborus punctipennis) and parasitism (the virulent fungus Metschnikowia bicuspidata) in experimental assemblages. Because we know natural populations of the prey (Daphnia dentifera) vary in susceptibility to both predator and parasite, we stocked experimental populations with nine genotypes spanning a broad range of susceptibility to both enemies. Predation significantly reduced infection prevalence, eliminating infection at the highest predation level. However, lower parasitism did not increase densities of prey; instead, prey density decreased substantially at the highest predation levels (a major density cost of healthy herds predation). This density result was predicted by a model parameterized for this system. The model specifies three conditions for predation to increase prey density during epidemics: (i) predators selectively feed on infected prey, (ii) consumed infected prey release fewer infectious propagules than unconsumed prey, and (iii) sufficiently low infection prevalence. While the system satisfied the first two conditions, prevalence remained too high to see an increase in prey density with predation. Low prey densities caused by high predation drove increases in algal resources of the prey, fueling greater reproduction, indicating that consumer-resource interactions can complicate predator-prey-parasite dynamics. Overall, in our experiment, predation reduced the prevalence of a virulent parasite but, at the highest levels, also reduced prey density. Hence, while healthy herds predation is possible under some conditions, our empirical results make it clear that the manipulation of predators to reduce parasite prevalence may harm prey density.
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Cadeia Alimentar , Comportamento Predatório , Animais , Densidade DemográficaRESUMO
AbstractTheory often predicts that host populations should evolve greater resistance when parasites become abundant. Furthermore, that evolutionary response could ameliorate declines in host populations during epidemics. Here, we argue for an update: when all host genotypes become sufficiently infected, higher parasite abundance can select for lower resistance because its cost exceeds its benefit. We illustrate such a "resistance is futile" outcome with mathematical and empirical approaches. First, we analyzed an eco-evolutionary model of parasites, hosts, and hosts' resources. We determined eco-evolutionary outcomes for prevalence, host density, and resistance (mathematically, "transmission rate") along ecological and trait gradients that alter parasite abundance. With high enough parasite abundance, hosts evolve lower resistance, amplifying infection prevalence and decreasing host density. In support of these results, a higher supply of nutrients drove larger epidemics of survival-reducing fungal parasites in a mesocosm experiment. In two-genotype treatments, zooplankton hosts evolved less resistance under high-nutrient conditions than under low-nutrient conditions. Less resistance, in turn, was associated with higher infection prevalence and lower host density. Finally, in an analysis of naturally occurring epidemics, we found a broad, bimodal distribution of epidemic sizes consistent with the resistance is futile prediction of the eco-evolutionary model. Together, the model and experiment, supplemented by the field pattern, support predictions that drivers of high parasite abundance can lead to the evolution of lower resistance. Hence, under certain conditions, the most fit strategy for individual hosts exacerbates prevalence and depresses host populations.
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Parasitos , Animais , Parasitos/genética , Interações Hospedeiro-Parasita/genética , Prevalência , Densidade Demográfica , GenótipoRESUMO
Ocean acidification can severely affect bivalve molluscs, especially their shell calcification. Assessing the fate of this vulnerable group in a rapidly acidifying ocean is therefore a pressing challenge. Volcanic CO2 seeps are natural analogues of future ocean conditions that offer unique insights into the scope of marine bivalves to cope with acidification. Here, we used a 2-month reciprocal transplantation of the coastal mussel Septifer bilocularis collected from reference and elevated pCO2 habitats to explore how they calcify and grow at CO2 seeps on the Pacific coast of Japan. We found significant decreases in condition index (an indication of tissue energy reserves) and shell growth of mussels living under elevated pCO2 conditions. These negative responses in their physiological performance under acidified conditions were closely associated with changes in their food sources (shown by changes to the soft tissue δ13C and δ15N ratios) and changes in their calcifying fluid carbonate chemistry (based on shell carbonate isotopic and elemental signatures). The reduced shell growth rate during the transplantation experiment was further supported by shell δ13C records along their incremental growth layers, as well as their smaller shell size despite being of comparable ontogenetic ages (5-7 years old, based on shell δ18O records). Taken together, these findings demonstrate how ocean acidification at CO2 seeps affects mussel growth and reveal that lowered shell growth helps them survive stressful conditions.
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Mytilidae , Água do Mar , Animais , Dióxido de Carbono , Concentração de Íons de Hidrogênio , Acidificação dos Oceanos , Carbonatos , Oceanos e MaresRESUMO
BACKGROUND: Advances in treatment for patients with Diffuse Large B-Cell Lymphoma (DLBCL) have led to improved patient outcomes but the magnitude of these disparities remains understudied with regards to improved survival outcomes. We sought to describe changes in DLBCL survival trends over time and explore potential differential survival patterns by patients' race/ethnicity and age. METHODS: We utilized the Surveillance, Epidemiology, and End Results (SEER) database to identify patients diagnosed with DLBCL from 1980 to 009 and determined 5-year survival outcomes for all patients, categorizing patients by year of diagnosis. We used descriptive statistics and logistic regression, adjusting for stage and year of diagnosis, to describe changes in 5-year survival rates over time by race/ethnicity and age. RESULTS: We identified 43,564 patients with DLBCL eligible for this study. Median age was 67 years (ages: 18-64 = 44.2%, 65-79 = 37.1%, 80 + = 18.7%). Most patients were male (53.4%) and had advanced stage III/IV disease (40.0%). Most patients were White race (81.4%), followed by Asian/Pacific Islander (API) (6.3%), Black (6.3%), Hispanic (5.4%), and American Indian/Alaska Native (AIAN) (0.05%). Overall, the 5-year survival rate improved from 35.1% in 1980 to 52.4% in 2009 across all races and age groups (odds ratio [OR] for 5-year survival with increasing year of diagnosis = 1.05, P < .001). Patients in racial/ethnic minority groups (API: OR = 0.86, P < .0001; Black: OR = 0.57, P < .0001; AIAN: OR = 0.51, P = .008; Hispanic: 0.76, P = 0.291) and older adults (ages 65-79: OR = 0.43, P < .0001; ages 80+: OR = 0.13, P < .0001) had lower 5-year survival rates after adjusting for race, age, stage, and diagnosis year. We found consistent improvement in the odds of 5-year survival for year of diagnosis across all race and ethnicity groups (White: OR = 1.05, P < .001; API: OR = 1.04, P < .001; Black: OR = 1.06, p<.001; AIAN: OR = 1.05, P < .001; Hispanic: OR = 1.05, P < .005) and age groups (ages 18-64: OR = 1.06, P < .001; ages 65-79: OR = 1.04, P < .001; ages 80+: OR = 1.04, P < .001). CONCLUSION: Patients with DLBCL experienced improvements in 5-year survival rates from 1980 to 2009, despite persistently lower survival among patients in racial/ethnic minority groups and older adults.
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Etnicidade , Disparidades nos Níveis de Saúde , Linfoma Difuso de Grandes Células B , Grupos Minoritários , Grupos Raciais , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Fatores Etários , Etnicidade/estatística & dados numéricos , Linfoma Difuso de Grandes Células B/etnologia , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/terapia , Grupos Minoritários/estatística & dados numéricos , Fatores Raciais , Grupos Raciais/estatística & dados numéricos , Programa de SEER , Taxa de Sobrevida/tendênciasRESUMO
Long-term environmental change, sudden pulses of extreme perturbation, or a combination of both can trigger regime shifts by changing the processes and feedbacks which determine community assembly, structure, and function, altering the state of ecosystems. Our understanding of the mechanisms that stabilise against regime shifts or lock communities into altered states is limited, yet also critical to anticipating future states, preventing regime shifts, and reversing unwanted state change. Ocean acidification contributes to the restructuring and simplification of algal systems, however the mechanisms through which this occurs and whether additional drivers are involved requires further study. Using monthly surveys over three years at a shallow-water volcanic seep we examined how the composition of algal communities change seasonally and following periods of significant physical disturbance by typhoons at three levels of ocean acidification (equivalent to means of contemporary â¼350 and future â¼500 and 900 µatm pCO2). Sites exposed to acidification were increasingly monopolised by structurally simple, fast-growing turf algae, and were clearly different to structurally complex macrophyte-dominated reference sites. The distinct contemporary and acidified community states were stabilised and maintained at their respective sites by different mechanisms following seasonal typhoon disturbance. Macroalgal-dominated sites were resistant to typhoon damage. In contrast, significant losses of algal biomass represented a near total ecosystem reset by typhoons for the turf-dominated communities at the elevated pCO2 sites (i.e. negligible resistance). A combination of disturbance and subsequent turf recovery maintained the same simplified state between years (elevated CO2 levels promote turf growth following algal removal, inhibiting macroalgal recruitment). Thus, ocean acidification may promote shifts in algal systems towards degraded ecosystem states, and short-term disturbances which reset successional trajectories may 'lock-in' these alternative states of low structural and functional diversity.
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Tempestades Ciclônicas , Ecossistema , Água do Mar/química , Concentração de Íons de Hidrogênio , Acidificação dos OceanosRESUMO
Why do parasites exhibit a wide dynamical range within their hosts? For instance, why does infecting dose either lead to infection or immune clearance? Why do some parasites exhibit boom-bust, oscillatory dynamics? What maintains parasite diversity, that is coinfection v single infection due to exclusion or priority effects? For insights on parasite dose, dynamics and diversity governing within-host infection, we turn to niche models. An omnivory food web model (IGP) blueprints one parasite competing with immune cells for host energy (PIE). Similarly, a competition model (keystone predation, KP) mirrors a new coinfection model (2PIE). We then drew analogies between models using feedback loops. The following three points arise: first, like in IGP, parasites oscillate when longer loops through parasites, immune cells and resource regulate parasite growth. Shorter, self-limitation loops (involving resources and enemies) stabilise those oscillations. Second, IGP can produce priority effects that resemble immune clearance. But, despite comparable loop structure, PIE cannot due to constraints imposed by production of immune cells. Third, despite somewhat different loop structure, KP and 2PIE share apparent and resource competition mechanisms that produce coexistence (coinfection) or priority effects of prey or parasites. Together, this mechanistic niche framework for within-host dynamics offers new perspective to improve individual health.
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Coinfecção , Parasitos , Animais , Humanos , Cadeia Alimentar , Retroalimentação , Comportamento Predatório/fisiologia , Interações Hospedeiro-Parasita/fisiologiaRESUMO
Despite widespread availability of vaccines, COVID-19 is a leading cause of death in the United States (US), and sociodemographic disparities in vaccine uptake remain. Race/ethnicity, partisanship, and perception of peer vaccination status are strong predictors of vaccine uptake, but research is limited among some racial/ethnic groups with small populations. The current study used an online survey to examine the relationship between these factors among a diverse sample of US adults (n = 1,674), with oversampling of racial and ethnic minorities. Respondents provided sociodemographic information and answered questions regarding COVID-19 vaccination status, political affiliation, perception of peers' vaccination status, COVID-19 death exposure, and previous COVID-19 infection. Respondents who identified as Asian American had higher odds of being vaccinated, whereas those who identified as Black/African American or American Indian or Alaska Native (AIAN) had lower odds. Respondents who identified as Independent/Other or Republican had lower vaccination odds. Respondents who perceived anything less than nearly all of their peers were vaccinated had lower vaccination odds. Further, lack of a primary care provider, younger age, and lower educational attainment were associated with lower vaccination odds. Findings may help to determine where additional work is needed to improve vaccine uptake in the US. Results indicate the need for intentional and tailored vaccination programs in Black/African American and AIAN communities; the need to understand how media and political actors develop vaccination messaging and impact vaccine uptake; and the need for additional research on how people estimate, understand, and form decisions around peer vaccination rates.
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Vacinas contra COVID-19 , COVID-19 , Política , Vacinação , Adulto , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19/administração & dosagem , Etnicidade , Estados Unidos , Vacinação/estatística & dados numéricosRESUMO
Plastics are accumulating in the world's oceans, while ocean waters are becoming acidified by increased CO2. We compared metagenome of biofilms on tethered plastic bottles in subtidal waters off Japan naturally enriched in CO2, compared to normal ambient CO2 levels. Extending from an earlier amplicon study of bacteria, we used metagenomics to provide direct insights into changes in the full range of functional genes and the entire taxonomic tree of life in the context of the changing plastisphere. We found changes in the taxonomic community composition of all branches of life. This included a large increase in diatom relative abundance across the treatments but a decrease in diatom diversity. Network complexity among families decreased with acidification, showing overall simplification of biofilm integration. With acidification, there was decreased prevalence of genes associated with cell-cell interactions and antibiotic resistance, decreased detoxification genes, and increased stress tolerance genes. There were few nutrient cycling gene changes, suggesting that the role of plastisphere biofilms in nutrient processes within an acidified ocean may not change greatly. Our results suggest that as ocean CO2 increases, the plastisphere will undergo broad-ranging changes in both functional and taxonomic composition, especially the ecologically important diatom group, with possible wider implications for ocean ecology.
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Diatomáceas , Água do Mar , Humanos , Plásticos , Concentração de Íons de Hidrogênio , Acidificação dos Oceanos , Dióxido de Carbono , Biofilmes , Diatomáceas/genéticaRESUMO
We administered a survey during the fifteen-minute wait time after the COVID-19 vaccine was given (N = 1475) to examine attitudes towards COVID-19 vaccines among adults who were vaccinated in Arkansas between April 22nd and July 6th, 2021. We found 60% of those who had just been vaccinated reported some level of hesitancy, including 10% who reported being "very hesitant." Hesitancy was not evenly distributed across sociodemographic groups (age, sex, race/ethnicity, and education) and was associated with whether a non-English language is spoken in the home, health care coverage, and flu vaccination over the past five years in bivariate analysis. Generalized ordered logistic regression results reveal associations between the log-ordered odds of COVID-19 vaccine hesitancy and age, sex, race/ethnicity, health care coverage, health literacy, and flu vaccination over the past five years. Surprisingly, a prior COVID-19 diagnosis was not significantly associated with COVID-19 vaccine hesitancy. These results can inform health care and communication strategies. Further attention to "hesitant adopters" can provide insights into the process of overcoming vaccine hesitancy that are critical to vaccine uptake.
Assuntos
Vacinas contra COVID-19 , COVID-19 , Adulto , Humanos , COVID-19/prevenção & controle , Comunicação , Correlação de Dados , Escolaridade , VacinaçãoRESUMO
The COVID-19 pandemic has disrupted the health care system, resulting in decreased health care utilization. During the pandemic, some patients chose to postpone clinic visits or avoid them altogether while health care providers concurrently scaled back their services. As a result, health care has shifted to a greater reliance on telehealth and virtual care. This study uses a qualitative descriptive design, focused on providing summaries of participant experiences of health care and telehealth utilization during the COVID-19 pandemic. Three primary themes emerged during analysis: delayed health care, avoidance of care, and experiences of telehealth. Sub-themes of delayed health care included care delays and scheduling difficulties. Participants reported avoidance of health care due to fear of COVID-19 infection, as well as general changes to care-seeking behaviors. Participants also reported positive experiences with telehealth, with some respondents noting limitations of telehealth systems, such as limitations on procedures and patient-centered monitoring of chronic illness. Our findings support studies that have found both health care delays and changes in health care utilization patterns during the pandemic. Most importantly, this study expands the literature concerning links between fear of COVID-19 and altered care-seeking behaviors, which is the first study to do so focusing on these concerns in the participants' own words. Finally, while telehealth is promising in preserving continuity of care during pandemics, long-term integration into the health care system is not without challenges, and this study provides insights into how patients experienced telehealth during COVID-19 in their own words. Data collection, survey design, and research priorities for this study were based on input from ongoing community partnerships.