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1.
Proc Natl Acad Sci U S A ; 118(21)2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33972407

RESUMO

Ocean warming and acidification threaten the future growth of coral reefs. This is because the calcifying coral reef taxa that construct the calcium carbonate frameworks and cement the reef together are highly sensitive to ocean warming and acidification. However, the global-scale effects of ocean warming and acidification on rates of coral reef net carbonate production remain poorly constrained despite a wealth of studies assessing their effects on the calcification of individual organisms. Here, we present global estimates of projected future changes in coral reef net carbonate production under ocean warming and acidification. We apply a meta-analysis of responses of coral reef taxa calcification and bioerosion rates to predicted changes in coral cover driven by climate change to estimate the net carbonate production rates of 183 reefs worldwide by 2050 and 2100. We forecast mean global reef net carbonate production under representative concentration pathways (RCP) 2.6, 4.5, and 8.5 will decline by 76, 149, and 156%, respectively, by 2100. While 63% of reefs are projected to continue to accrete by 2100 under RCP2.6, 94% will be eroding by 2050 under RCP8.5, and no reefs will continue to accrete at rates matching projected sea level rise under RCP4.5 or 8.5 by 2100. Projected reduced coral cover due to bleaching events predominately drives these declines rather than the direct physiological impacts of ocean warming and acidification on calcification or bioerosion. Presently degraded reefs were also more sensitive in our analysis. These findings highlight the low likelihood that the world's coral reefs will maintain their functional roles without near-term stabilization of atmospheric CO2 emissions.


Assuntos
Antozoários/fisiologia , Carbonato de Cálcio/metabolismo , Mudança Climática , Recifes de Corais , Animais , Antozoários/química , Carbonato de Cálcio/química , Humanos , Concentração de Íons de Hidrogênio , Oceanos e Mares , Água do Mar/química
2.
Public Health Nurs ; 40(5): 758-761, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37462182

RESUMO

We report on five SARS-CoV-2 congregate setting outbreaks at U.S. Operation Allies Welcome Safe Havens/military facilities. Outbreak data were collected, and attack rates were calculated for various populations. Even in vaccinated populations, there was rapid spread, illustrating the importance of institutional prevention and mitigation policies in congregate settings.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Surtos de Doenças/prevenção & controle , Instalações de Saúde
3.
Ecol Appl ; 31(2): e02234, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33064870

RESUMO

Reef-building corals, like many long-lived organisms, experience environmental change as a combination of separate but concurrent processes, some of which are gradual yet long-lasting, while others are more acute but short-lived. For corals, some chronic environmental stressors, such as rising temperature and ocean acidification, are thought to induce gradual changes in colonies' vital rates. Meanwhile, other environmental changes, such as the intensification of tropical cyclones, change the disturbance regime that corals experience. Here, we use a physiologically structured population model to explore how chronic environmental stressors that impact the vital rates of individual coral colonies interact with the intensity and magnitude of disturbance to affect coral population dynamics and cover. We find that, when disturbances are relatively benign, intraspecific density dependence driven by space competition partially buffers coral populations against gradual changes in vital rates. However, the impact of chronic stressors is amplified in more highly disturbed environments, because disturbance weakens the buffering effect of space competition. We also show that coral cover is more sensitive to changes in colony growth and mortality than to external recruitment, at least in open populations, and that space competition and size structure mediate the extent and pace of coral population recovery following a large-scale mortality event. Understanding the complex interplay among chronic environmental stressors, mass-mortality events, and population size structure sharpens our ability to manage and to restore coral-reef ecosystems in an increasingly disturbed future.


Assuntos
Antozoários , Animais , Recifes de Corais , Ecossistema , Concentração de Íons de Hidrogênio , Água do Mar
4.
Ecol Appl ; 31(1): e2227, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32918509

RESUMO

Nutrient pollution is altering coastal ecosystems worldwide. On coral reefs, excess nutrients can favor the production of algae at the expense of reef-building corals, yet the role of nutrients in driving community changes such as shifts from coral to macroalgae is not well understood. Here we investigate the potential role of anthropogenic nutrient loading in driving recent coral-to-macroalgae phase shifts on reefs in the lagoons surrounding the Pacific island of Moorea, French Polynesia. We use nitrogen (N) tissue content and stable isotopes (δ15 N) in an abundant macroalga (Turbinaria ornata) together with empirical models of nutrient discharge to describe spatial and temporal patterns of nutrient enrichment in the lagoons. We then employ time series data to test whether recent increases in macroalgae are associated with nutrients. Our results revealed that patterns of N enrichment were linked to several factors, including rainfall, wave-driven circulation, and distance from anthropogenic nutrient sources, especially human sewage. Reefs near large watersheds, where inputs of N from sewage and agriculture are high, have been consistently enriched in N for at least the last decade. In many of these areas, corals have decreased and macroalgae have increased, while reefs with lower levels of N input have maintained high cover of coral and low cover of macroalgae. Importantly, these patchy phase shifts to macroalgae have occurred despite substantial island-wide increases in the density and biomass of herbivorous fishes over the time period. Together, these results indicate that nutrient loading may be an important driver of coral-to-macroalgae phase shifts in the lagoons of Moorea even though the reefs harbor an abundant and diverse herbivore assemblage. These results emphasize the important role that bottom-up factors can play in driving coral-to-macroalgae phase shifts and underscore the critical importance of watershed management for reducing inputs of nutrients and other land-based pollutants to coral reef ecosystems.


Assuntos
Antozoários , Recifes de Corais , Animais , Ecossistema , Peixes , Humanos , Nutrientes
5.
Biol Lett ; 14(7)2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29997188

RESUMO

Ocean acidification (OA) and nutrient enrichment threaten the persistence of near shore ecosystems, yet little is known about their combined effects on marine organisms. Here, we show that a threefold increase in nitrogen concentrations, simulating enrichment due to coastal eutrophication or consumer excretions, offset the direct negative effects of near-future OA on calcification and photophysiology of the reef-building crustose coralline alga, Porolithon onkodes Projected near-future pCO2 levels (approx. 850 µatm) decreased calcification by 30% relative to ambient conditions. Conversely, nitrogen enrichment (nitrate + nitrite and ammonium) increased calcification by 90-130% in ambient and high pCO2 treatments, respectively. pCO2 and nitrogen enrichment interactively affected instantaneous photophysiology, with highest relative electron transport rates under high pCO2 and high nitrogen. Nitrogen enrichment alone increased concentrations of the photosynthetic pigments chlorophyll a, phycocyanin and phycoerythrin by approximately 80-450%, regardless of pCO2 These results demonstrate that nutrient enrichment can mediate direct organismal responses to OA. In natural systems, however, such direct benefits may be counteracted by simultaneous increases in negative indirect effects, such as heightened competition. Experiments exploring the effects of multiple stressors are increasingly becoming important for improving our ability to understand the ramifications of local and global change stressors in near shore ecosystems.


Assuntos
Compostos de Nitrogênio/farmacologia , Rodófitas/fisiologia , Água do Mar/química , Calcificação Fisiológica , Dióxido de Carbono/efeitos adversos , Fotossíntese/fisiologia , Rodófitas/metabolismo , Poluentes Químicos da Água/efeitos adversos
6.
Glob Chang Biol ; 22(3): 1225-34, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26154126

RESUMO

To date, studies of ocean acidification (OA) on coral reefs have focused on organisms rather than communities, and the few community effects that have been addressed have focused on shallow back reef habitats. The effects of OA on outer barrier reefs, which are the most striking of coral reef habitats and are functionally and physically different from back reefs, are unknown. Using 5-m long outdoor flumes to create treatment conditions, we constructed coral reef communities comprised of calcified algae, corals, and reef pavement that were assembled to match the community structure at 17 m depth on the outer barrier reef of Moorea, French Polynesia. Communities were maintained under ambient and 1200 µatm pCO2 for 7 weeks, and net calcification rates were measured at different flow speeds. Community net calcification was significantly affected by OA, especially at night when net calcification was depressed ~78% compared to ambient pCO2 . Flow speed (2-14 cm s(-1) ) enhanced net calcification only at night under elevated pCO2 . Reef pavement also was affected by OA, with dissolution ~86% higher under elevated pCO2 compared to ambient pCO2 . These results suggest that net accretion of outer barrier reef communities will decline under OA conditions predicted within the next 100 years, largely because of increased dissolution of reef pavement. Such extensive dissolution poses a threat to the carbonate foundation of barrier reef communities.


Assuntos
Antozoários/química , Calcificação Fisiológica , Dióxido de Carbono/química , Recifes de Corais , Água do Mar/química , Animais , Carbonatos/química , Polinésia
7.
Antimicrob Agents Chemother ; 59(12): 7178-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26149988

RESUMO

Clostridium difficile is a leading cause of antibiotic-associated diarrhea and the etiologic agent responsible for C. difficile infection. Toxin A (TcdA) and toxin B (TcdB) are nearly indispensable virulence factors for Clostridium difficile pathogenesis. Given the toxin-centric mechanism by which C. difficile pathogenesis occurs, the selective sequestration with neutralization of TcdA and TcdB by nonantibiotic agents represents a novel mode of action to prevent or treat C. difficile-associated disease. In this preclinical study, we used quantitative enzyme immunoassays to determine the extent by which a novel drug, calcium aluminosilicate uniform particle size nonswelling M-1 (CAS UPSN M-1), is capable of sequestering TcdA and TcdB in vitro. The following major findings were derived from the present study. First, we show that CAS UPSN M-1 efficiently sequestered both TcdA and TcdB to undetectable levels. Second, we show that CAS UPSN M-1's affinity for TcdA is greater than its affinity for TcdB. Last, we show that CAS UPSN M-1 exhibited limited binding affinity for nontarget proteins. Taken together, these results suggest that ingestion of calcium aluminosilicate might protect gastrointestinal tissues from antibiotic- or chemotherapy-induced C. difficile infection by neutralizing the cytotoxic and proinflammatory effects of luminal TcdA and TcdB.


Assuntos
Silicatos de Alumínio/química , Proteínas de Bactérias/química , Toxinas Bacterianas/química , Clostridioides difficile/química , Enterotoxinas/química , Desintoxicação por Sorção/métodos , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Toxinas Bacterianas/biossíntese , Toxinas Bacterianas/genética , Toxinas Bacterianas/isolamento & purificação , Argila , Clostridioides difficile/genética , Clostridioides difficile/patogenicidade , Enterotoxinas/biossíntese , Enterotoxinas/genética , Enterotoxinas/isolamento & purificação , Expressão Gênica , Técnicas Imunoenzimáticas , Tamanho da Partícula , Ligação Proteica , Soluções
8.
J Clin Microbiol ; 53(2): 716-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25428153

RESUMO

Acid-fast bacillus (AFB) spinal osteomyelitis in a patient with AIDS is often presumed to be caused by reactivated Mycobacterium tuberculosis. However, other AFB pathogens can mimic M. tuberculosis and, to ensure appropriate and adequate therapy, should be considered by clinicians. We present a case of aggressive spinal osteomyelitis caused by Mycobacterium heckeshornense in an AIDS patient; a review of the literature is also included.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Tuberculose da Coluna Vertebral/diagnóstico , Tuberculose da Coluna Vertebral/microbiologia , Discite/diagnóstico , Discite/microbiologia , Discite/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Osteomielite/diagnóstico , Osteomielite/microbiologia , Osteomielite/patologia , Radiografia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/patologia , Tuberculose da Coluna Vertebral/patologia
9.
Ecology ; 96(1): 241-51, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26236909

RESUMO

Kelps are conspicuous foundation species in marine ecosystems that alter the composition of understory algal assemblages. While this may be due to changes in the competitive interactions between algal species, how kelp canopies mediate propagule supply and establishment success of understory algae is not well known. In Southern California, USA, Eisenia arborea forms dense kelp canopies in shallow subtidal environments and is associated with an understory dominated by red algal species. In canopy-free areas, however, the algal assemblage is comprised of mostly brown algal species. We used a combination of mensurative and manipulative experiments to test whether Eisenia facilitates the understory assemblage by reducing competition between these different types of algae by changes in biotic interactions and/or recruitment. Our results show Eisenia facilitates a red algal assemblage via inhibition of brown algal settlement into the canopy zone, allowing recruitment to occur by vegetative means rather than establishment of new individuals. In the canopy-free zone, however, high settlement and recruitment rates suggest competitive interactions shape the community there. These results demonstrate that foundation species alter the distribution and abundance of associated organisms by affecting not only interspecific interactions but also propagule supply and recruitment limitation.


Assuntos
Ecossistema , Kelp , California , Rodófitas
10.
Blood ; 122(25): 4129-39, 2013 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-24055823

RESUMO

New treatments are needed for B-cell malignancies persisting after allogeneic hematopoietic stem cell transplantation (alloHSCT). We conducted a clinical trial of allogeneic T cells genetically modified to express a chimeric antigen receptor (CAR) targeting the B-cell antigen CD19. T cells for genetic modification were obtained from each patient's alloHSCT donor. All patients had malignancy that persisted after alloHSCT and standard donor lymphocyte infusions (DLIs). Patients did not receive chemotherapy prior to the CAR T-cell infusions and were not lymphocyte depleted at the time of the infusions. The 10 treated patients received a single infusion of allogeneic anti-CD19-CAR T cells. Three patients had regressions of their malignancies. One patient with chronic lymphocytic leukemia (CLL) obtained an ongoing complete remission after treatment with allogeneic anti-CD19-CAR T cells, another CLL patient had tumor lysis syndrome as his leukemia dramatically regressed, and a patient with mantle cell lymphoma obtained an ongoing partial remission. None of the 10 patients developed graft-versus-host disease (GVHD). Toxicities included transient hypotension and fever. We detected cells containing the anti-CD19-CAR gene in the blood of 8 of 10 patients. These results show for the first time that donor-derived allogeneic anti-CD19-CAR T cells can cause regression of B-cell malignancies resistant to standard DLIs without causing GVHD.


Assuntos
Antígenos CD19 , Transfusão de Linfócitos , Linfoma de Células B/terapia , Receptores de Antígenos de Linfócitos T/biossíntese , Transplante de Células-Tronco , Linfócitos T/metabolismo , Linfócitos T/transplante , Adulto , Idoso , Aloenxertos , Feminino , Humanos , Linfoma de Células B/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes de Fusão/biossíntese , Síndrome de Lise Tumoral/etiologia , Síndrome de Lise Tumoral/terapia
11.
Breast Cancer Res Treat ; 144(3): 569-76, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24562823

RESUMO

The aim of this multicenter, prospective, longitudinal phase IV study was to establish the optimal duration of neoadjuvant letrozole that would allow breast conservation surgery (BCS) in patients with early breast cancer who were initially unsuitable. Primary, invasive, estrogen-receptor- and/or progesterone-receptor-positive breast cancer patients, with large tumors (≥T2 i.e., >20 mm) not initially suitable for BCS, received 2.5 mg letrozole p.o. daily. Patients continued treatment until they became eligible for BCS, progressed, failed to meet criteria for BCS and withdrew for scheduled mastectomy, withdrew for other reasons, or completed 12 months of letrozole treatment without a BCS decision being made. A total of 146 patients were enrolled; seven patients who did not have a valid postbaseline tumor assessment were excluded from the final efficacy analysis. At study closure, 69 % of patients (96 of 139) were eligible for BCS. The median time to achieve a tumor response sufficient to allow BCS with neoadjuvant letrozole was 7.5 months (95 % CI 6.3-8.5 months). Letrozole was well tolerated, and most adverse events were mild-to-moderate (grade 1-2). The results from this trial suggest that extended letrozole therapy in the neoadjuvant setting (7.5 months), as opposed to conventional treatment of 4 months, is optimal to achieve maximum reduction in tumor volume sufficient for BCS.


Assuntos
Antineoplásicos/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Mastectomia Segmentar , Nitrilas/uso terapêutico , Triazóis/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Inibidores da Aromatase/administração & dosagem , Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/mortalidade , Feminino , Humanos , Letrozol , Pessoa de Meia-Idade , Terapia Neoadjuvante , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Nitrilas/administração & dosagem , Nitrilas/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Triazóis/administração & dosagem , Triazóis/efeitos adversos
12.
Blood ; 119(12): 2709-20, 2012 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-22160384

RESUMO

We conducted a clinical trial to assess adoptive transfer of T cells genetically modified to express an anti-CD19 chimeric Ag receptor (CAR). Our clinical protocol consisted of chemotherapy followed by an infusion of anti-CD19-CAR-transduced T cells and a course of IL-2. Six of the 8 patients treated on our protocol obtained remissions of their advanced, progressive B-cell malignancies. Four of the 8 patients treated on the protocol had long-term depletion of normal polyclonal CD19(+) B-lineage cells. Cells containing the anti-CD19 CAR gene were detected in the blood of all patients. Four of the 8 treated patients had prominent elevations in serum levels of the inflammatory cytokines IFNγ and TNF. The severity of acute toxicities experienced by the patients correlated with serum IFNγ and TNF levels. The infused anti-CD19-CAR-transduced T cells were a possible source of these inflammatory cytokines because we demonstrated peripheral blood T cells that produced TNF and IFNγ ex vivo in a CD19-specific manner after anti-CD19-CAR-transduced T-cell infusions. Anti-CD19-CAR-transduced T cells have great promise to improve the treatment of B-cell malignancies because of a potent ability to eradicate CD19(+) cells in vivo; however, reversible cytokine-associated toxicities occurred after CAR-transduced T-cell infusions.


Assuntos
Linfócitos B/imunologia , Citocinas/efeitos adversos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Leucemia Linfocítica Crônica de Células B/terapia , Linfoma de Células B/terapia , Linfócitos T/imunologia , Antígenos CD19/imunologia , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Leucemia Linfocítica Crônica de Células B/imunologia , Linfoma de Células B/imunologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/uso terapêutico , Indução de Remissão , Linfócitos T/transplante , Transdução Genética
13.
Clin Endocrinol (Oxf) ; 81(1): 25-30, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24274335

RESUMO

CONTEXT: In patients with primary aldosteronism (PA), adrenalectomy is potentially curative for those correctly identified as having unilateral excessive aldosterone production. It has been suggested that a recently developed and published clinical prediction score (CPS) may correctly identify some patients as having unilateral disease, without recourse to adrenal venous sampling. OBJECTIVE: We have applied the CPS to a large cohort of PA patients with defined and documented outcomes. We also incorporated a minor modification to the CPS and a radiological grading score (RGS) into our analysis to assess whether its performance could be augmented. RESULTS: A total of 75 patients with a robust diagnosis following bilateral adrenal venous cannulation and/or strictly defined surgical outcome were analysed. Applying the CPS to this group of patients produced a sensitivity of 38·8% and a specificity of 88·5% of correctly identifying unilateral aldosterone production. Using a suggested modification to the CPS, in which different levels of hypokalaemia were given different weightings, the sensitivity rose to 40·8%, with an identical specificity. Using the RGS alone improved sensitivity to 91·7%, but specificity was reduced to 62·5%. CONCLUSION: Applying the recently developed CPS to this cohort of patients, it was not possible to reproduce the 100% specificity reported in the original publication. Using the modified score or incorporating the RGS did not improve its performance. In this cohort, we were unable to show superiority of the CPS over an imaging-based strategy. CPS may have a role in guiding clinical decision-making, especially in those whose adrenal venous sampling (AVS) has been unsuccessful.


Assuntos
Hiperaldosteronismo/diagnóstico , Glândulas Suprarrenais/metabolismo , Glândulas Suprarrenais/patologia , Adulto , Idoso , Aldosterona/sangue , Feminino , Humanos , Hiperaldosteronismo/sangue , Hiperaldosteronismo/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Tomografia Computadorizada por Raios X , Adulto Jovem
14.
Npj Spintron ; 2(1): 14, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38883426

RESUMO

Magnetic random access memory (MRAM) is a leading emergent memory technology that is poised to replace current non-volatile memory technologies such as eFlash. However, controlling and improving distributions of device properties becomes a key enabler of new applications at this stage of technology development. Here, we introduce a non-contact metrology technique deploying scanning NV magnetometry (SNVM) to investigate MRAM performance at the individual bit level. We demonstrate magnetic reversal characterization in individual, <60 nm-sized bits, to extract key magnetic properties, thermal stability, and switching statistics, and thereby gauge bit-to-bit uniformity. We showcase the performance of our method by benchmarking two distinct bit etching processes immediately after pattern formation. In contrast to ensemble averaging methods such as perpendicular magneto-optical Kerr effect, we show that it is possible to identify out of distribution (tail-bits) bits that seem associated to the edges of the array, enabling failure analysis of tail bits. Our findings highlight the potential of nanoscale quantum sensing of MRAM devices for early-stage screening in the processing line, paving the way for future incorporation of this nanoscale characterization tool in the semiconductor industry.

15.
Sci Rep ; 13(1): 20490, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993658

RESUMO

The distribution of the easy-axes in an array of MRAM cells is a vital parameter to understand the switching and characteristics of the devices. By measuring the coercivity as a function of applied-field angle, and remaining close to the perpendicular orientation, a classic Stoner-Wohlfarth approximation has been applied to the resulting variation to determine the standard deviation, [Formula: see text], of a Gaussian distribution of the orientation of the easy-magnetisation directions. In this work we have compared MRAM arrays with nominal cells sizes of 20 nm and 60 nm and a range of free layer thicknesses. We have found that a smaller diameter cell will have a wider switching-field distribution with a standard deviation [Formula: see text]. The MRAM arrays consist of pillars produced by etching a multilayer thin film. This value of [Formula: see text] is dominated by pillar uniformity and edge effects controlling the reversal, reinforcing the need for ever-improving etch processes. This is compared to larger pillars, with distributions as low as [Formula: see text]. Furthermore we found that the distribution broadens from [Formula: see text] to [Formula: see text] with free layer thickness in larger pillars and that thinner films had a more uniform easy-axis orientation. For the 20 nm pillars the non-uniform size distribution of the pillars, with a large and unknown error in the free-layer volume, was highlighted as it was found that the activation volume for the reversal of the free layer 930 nm[Formula: see text] was larger than the nominal physical volume of the free layer. However for the 60 nm pillars, the activation volume was measured to be equal to one fifth of their physical volume. This implies that the smaller pillars effectively reverse as one entity while the larger pillars reverse via an incoherent mechanism of nucleation and propagation.

16.
Med Sci Educ ; 33(2): 611-622, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37261025

RESUMO

Background: Clinical settings represent the site of patient care and clinical training for medical students and residents. Both processes involve social interaction, and humor is a fundamental component of social interaction that remains underexplored in medical education. This study investigated the impact of humor on medical trainees in the context of the clinical learning environment and examined the implications for medical educators. Methods: Following scoping review methodology, the authors systematically searched six databases and Google Scholar in February 2021 and March 2022. Articles were screened and selected according to inclusion/exclusion criteria, and findings from included articles were synthesized using procedures of metasynthesis. Results: Fifteen articles met inclusion criteria. Six themes emerged relating to the functions and effects of humor in clinical training settings: (1) managing emotions; (2) demarcating insider vs outsider status; (3) facilitating camaraderie; (4) ensuring conformity; (5) negotiating power differentials; and (6) fostering discrimination. Conclusions: The use of humor by medical educators plays an integral role in trainees' everyday experiences. Positive humor helps with coping and communication, while negative humor serves as an indirect medium for communicating ridicule and prejudice. Further research drawing on social psychology theories may identify ways to reduce effects of negative humor and promote well-being and diversity in medical education. Supplementary Information: The online version contains supplementary material available at 10.1007/s40670-023-01769-0.

17.
G3 (Bethesda) ; 13(8)2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-36929840

RESUMO

Alzheimer's disease (AD) is an age-related disorder that results in progressive cognitive impairment and memory loss. Deposition of amyloid ß (Aß) peptides in senile plaques is a hallmark of AD. γ-secretase produces Aß peptides, mostly as the soluble Aß40 with fewer insoluble Aß42 peptides. Rare, early-onset AD (EOAD) occurs in individuals under 60 years of age. Most EOAD cases are due to unknown genetic causes, but a subset is due to mutations in the genes encoding the amyloid precursor protein that is processed into Aß peptides or the presenilins (PS1 and PS2) that process APP. PS1 interacts with the epsilon isoform of glial fibrillary acidic protein (GFAPɛ), a protein found in the subventricular zone of the brain. We have found that GFAPɛ interacts with the telomere protection factor RAP1 (TERF2IP). RAP1 can also interact with PS1 alone or with GFAPɛ in vitro. Our data show that the nuclear protein RAP1 has an extratelomeric role in the cytoplasm through its interactions with GFAPɛ and PS1. GFAPɛ coprecipitated with RAP1 from human cell extracts. RAP1, GFAPɛ, and PS1 all colocalized in human SH-SY5Y cells. Using a genetic model of the γ-secretase complex in Saccharomyces cerevisiae, RAP1 increased γ-secretase activity, and this was potentiated by GFAPɛ. Our studies are the first to connect RAP1 with an age-related disorder.


Assuntos
Doença de Alzheimer , Neuroblastoma , Proteínas de Saccharomyces cerevisiae , Humanos , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/genética , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Proteína Glial Fibrilar Ácida/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Complexo Shelterina , Proteínas de Ligação a Telômeros/genética , Fatores de Transcrição/genética
19.
Clin Endocrinol (Oxf) ; 76(2): 182-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21895732

RESUMO

CONTEXT: In primary aldosteronism (PA), discriminating unilateral from bilateral disease is crucial because adrenalectomy is frequently curative in the former case but rarely helps in the latter. Various series have reported the utility of postural stimulation testing (PST), cross-sectional imaging and adrenal vein sampling (AVS) in the assessment of PA, but most of these studies were retrospective. OBJECTIVE: To prospectively determine the diagnostic utility of PST, AVS and computed tomography (CT) using a radiological scoring system in the assessment of PA in a tertiary centre, as well as to document the incidence of autonomous cortisol cosecretion. DESIGN AND SETTING: Fifty consecutive patients with PA underwent PST, CT, AVS and a low-dose dexamethasone suppression test with measurement of serum cortisol at 48 h. For patients who underwent surgery, histological confirmation, and a normal postoperative serum aldosterone concentration and plasma renin activity were taken as evidence for unilateral disease. For other patients, results from successful adrenal vein sampling were the diagnostic evidence against which CT and PST were assessed. RESULTS: Postural stimulation testing had a sensitivity and specificity of 44-56% and 71-75%, respectively. CT had an overall sensitivity and specificity of 77% and 80%, respectively, rising to 100% sensitivity and specificity if there was a single, discrete macronodule with an unequivocally normal contralateral gland. Evidence of cosecretion of cortisol occurred in 14% of patients. CONCLUSIONS: Preliminary experience is presented of an objective radiological scoring system for selecting patients with PA for AVS. PST provides little, if any, useful additional information. A significant minority of patients with PA exhibit evidence of cortisol cosecretion, which may have implications for perioperative management.


Assuntos
Glândulas Suprarrenais/diagnóstico por imagem , Hiperaldosteronismo/diagnóstico , Postura , Tomografia Computadorizada por Raios X/métodos , Glândulas Suprarrenais/irrigação sanguínea , Adulto , Idoso , Aldosterona/sangue , Cateterismo , Diagnóstico Diferencial , Feminino , Humanos , Hidrocortisona/sangue , Hiperaldosteronismo/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
20.
J Pathol ; 223(5): 646-58, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21341269

RESUMO

Integrin α9ß1 is a receptor for ECM proteins, including Tenascin-C and the EDA domain of fibronectin, and has been shown to transduce TGFß signalling. This study has examined the expression pattern of α9ß1 in 141 frozen breast carcinoma samples and related expression to prognostic indices, molecular subtype and patient outcome. Effects of α9ß1 on tumour cell migration and invasion were assessed using blocking antibody and gene transduction approaches. Integrin α9ß1 localized to myoepithelial cells in normal ducts and acini, a pattern maintained in DCIS. A subset (17%) of invasive carcinomas exhibited tumour cell expression of α9ß1, which related significantly to the basal-like phenotype, as defined by either CK5/6 or CK14 expression. Tumour expression of α9ß1 showed a significant association with reduced overall patient survival (p < 0.0001; HR 5.94, 95%CI 3.26-10.82) and with reduced distant-metastasis-free survival (p < 0.0001; HR 6.37, CI 3.51-11.58). A series of breast cancer cell lines was screened for α9ß1 with the highly invasive basal-like GI-101 cell line expressing significant levels. Both migration and invasion of this line were reduced significantly in the presence of α9-blocking antibody and following α9-knockdown with siRNA. Conversely, migratory and invasive behaviour of α9-negative MCF7 cells and α9-low MDA MB468 cells was enhanced significantly by over-expression of α9. Thus, α9ß1 acts as a novel marker of the basal-like breast cancer subtype and expression is associated with reduced survival, while its ability to promote breast cancer cell migration and invasion suggests that it contributes to the aggressive clinical behaviour of this tumour subtype.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Integrinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Membrana Celular/metabolismo , Movimento Celular/fisiologia , Proliferação de Células , Feminino , Humanos , Integrinas/fisiologia , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , Proteínas de Neoplasias/fisiologia , Fenótipo , Prognóstico , Análise de Sobrevida , Células Tumorais Cultivadas
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