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1.
Proc Natl Acad Sci U S A ; 119(34): e2211370119, 2022 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-35969740

RESUMEN

Sepsis, defined as organ dysfunction caused by a dysregulated host-response to infection, is characterized by immunosuppression. The vasopressor norepinephrine is widely used to treat low blood pressure in sepsis but exacerbates immunosuppression. An alternative vasopressor is angiotensin-II, a peptide hormone of the renin-angiotensin system (RAS), which displays complex immunomodulatory properties that remain unexplored in severe infection. In a murine cecal ligation and puncture (CLP) model of sepsis, we found alterations in the surface levels of RAS proteins on innate leukocytes in peritoneum and spleen. Angiotensin-II treatment induced biphasic, angiotensin-II type 1 receptor (AT1R)-dependent modulation of the systemic inflammatory response and decreased bacterial counts in both the blood and peritoneal compartments, which did not occur with norepinephrine treatment. The effect of angiotensin-II was preserved when treatment was delivered remote from the primary site of infection. At an independent laboratory, angiotensin-II treatment was compared in LysM-Cre AT1aR-/- (Myeloid-AT1a-) mice, which selectively do not express AT1R on myeloid-derived leukocytes, and littermate controls (Myeloid-AT1a+). Angiotensin-II treatment significantly reduced post-CLP bacteremia in Myeloid-AT1a+ mice but not in Myeloid-AT1a- mice, indicating that the AT1R-dependent effect of angiotensin-II on bacterial clearance was mediated through myeloid-lineage cells. Ex vivo, angiotensin-II increased post-CLP monocyte phagocytosis and ROS production after lipopolysaccharide stimulation. These data identify a mechanism by which angiotensin-II enhances the myeloid innate immune response during severe systemic infection and highlight a potential role for angiotensin-II to augment immune responses in sepsis.


Asunto(s)
Angiotensina II , Bacteriemia/inmunología , Células Mieloides/metabolismo , Sepsis/inmunología , Angiotensina II/metabolismo , Animales , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , Norepinefrina/metabolismo , Receptor de Angiotensina Tipo 1 , Sepsis/metabolismo , Transducción de Señal
2.
Glob Chang Biol ; 30(3): e17245, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38511487

RESUMEN

The seasonal coupling of plant and soil microbial nutrient demands is crucial for efficient ecosystem nutrient cycling and plant production, especially in strongly seasonal alpine ecosystems. Yet, how these seasonal nutrient cycling processes are modified by climate change and what the consequences are for nutrient loss and retention in alpine ecosystems remain unclear. Here, we explored how two pervasive climate change factors, reduced snow cover and shrub expansion, interactively modify the seasonal coupling of plant and soil microbial nitrogen (N) cycling in alpine grasslands, which are warming at double the rate of the global average. We found that the combination of reduced snow cover and shrub expansion disrupted the seasonal coupling of plant and soil N-cycling, with pronounced effects in spring (shortly after snow melt) and autumn (at the onset of plant senescence). In combination, both climate change factors decreased plant organic N-uptake by 70% and 82%, soil microbial biomass N by 19% and 38% and increased soil denitrifier abundances by 253% and 136% in spring and autumn, respectively. Shrub expansion also individually modified the seasonality of soil microbial community composition and stoichiometry towards more N-limited conditions and slower nutrient cycling in spring and autumn. In winter, snow removal markedly reduced the fungal:bacterial biomass ratio, soil N pools and shifted bacterial community composition. Taken together, our findings suggest that interactions between climate change factors can disrupt the temporal coupling of plant and soil microbial N-cycling processes in alpine grasslands. This could diminish the capacity of these globally widespread alpine ecosystems to retain N and support plant productivity under future climate change.


Asunto(s)
Ecosistema , Suelo , Cambio Climático , Estaciones del Año , Microbiología del Suelo , Nutrientes
3.
Theor Popul Biol ; 155: 67-76, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38092137

RESUMEN

Consider the diffusion process defined by the forward equation ut(t,x)=12{xu(t,x)}xx-α{xu(t,x)}x for t,x≥0 and -∞<α<∞, with an initial condition u(0,x)=δ(x-x0). This equation was introduced and solved by Feller to model the growth of a population of independently reproducing individuals. We explore important coalescent processes related to Feller's solution. For any α and x0>0 we calculate the distribution of the random variable An(s;t), defined as the finite number of ancestors at a time s in the past of a sample of size n taken from the infinite population of a Feller diffusion at a time t since its initiation. In a subcritical diffusion we find the distribution of population and sample coalescent trees from time t back, conditional on non-extinction as t→∞. In a supercritical diffusion we construct a coalescent tree which has a single founder and derive the distribution of coalescent times.

4.
Am Heart J ; 262: 20-28, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37015308

RESUMEN

BACKGROUND: Acute kidney injury (AKI), including contrast-induced AKI (CI-AKI), is an important complication of percutaneous coronary intervention (PCI), resulting in short- and long-term adverse clinical outcomes. While prior research has reported an increased cost burden to hospitals from CI-AKI, the incremental cost to payers remains unknown. Understanding this incremental cost may inform decisions and even policy in the future. The objective of this study was to estimate the short- and long-term cost to Medicare of AKI overall, and specifically CI-AKI, in PCI. METHODS: Patients undergoing inpatient PCI between January 2017 and June 2020 were selected from Medicare 100% fee-for-service data. Baseline clinical characteristics, PCI lesion/procedural characteristics, and AKI/CI-AKI during the PCI admission, were identified from diagnosis and procedure codes. Poisson regression, generalized linear modelling, and longitudinal mixed effects modelling, in full and propensity-matched cohorts, were used to compare PCI admission length of stay (LOS) and cost (Medicare paid amount inflated to 2022 US$), as well as total costs during 1-year following PCI, between AKI and non-AKI patients. RESULTS: The study cohort included 509,039 patients, of whom 104,033 (20.4%) were diagnosed with AKI and 9,691 (1.9%) with CI-AKI. In the full cohort, AKI was associated with +4.12 (95% confidence interval = 4.10, 4.15) days index PCI admission LOS, +$11,313 ($11,093, $11,534) index admission costs, and +$14,800 ($14,359, $15,241) total 1-year costs. CI-AKI was associated with +3.03 (2.97, 3.08) days LOS, +$6,566 ($6,148, $6,984) index admission costs, and +$13,381 ($12,118, $14,644) cumulative 1-year costs (all results are adjusted for baseline characteristics). Results from the propensity-matched analyses were similar. CONCLUSIONS: AKI, and specifically CI-AKI, during PCI is associated with significantly longer PCI admission LOS, PCI admission costs, and long-terms costs.


Asunto(s)
Lesión Renal Aguda , Intervención Coronaria Percutánea , Humanos , Anciano , Estados Unidos/epidemiología , Intervención Coronaria Percutánea/métodos , Factores de Riesgo , Medicare , Predicción , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/epidemiología , Medios de Contraste/efectos adversos
5.
J Math Biol ; 86(6): 98, 2023 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-37233854

RESUMEN

Recombination is a fundamental evolutionary force, but it is difficult to quantify because the effect of a recombination event on patterns of variation in a sample of genetic data can be hard to discern. Estimators for the recombination rate, which are usually based on the idea of integrating over the unobserved possible evolutionary histories of a sample, can therefore be noisy. Here we consider a related question: how would an estimator behave if the evolutionary history actually was observed? This would offer an upper bound on the performance of estimators used in practice. In this paper we derive an expression for the maximum likelihood estimator for the recombination rate based on a continuously observed, multi-locus, Wright-Fisher diffusion of haplotype frequencies, complementing existing work for an estimator of selection. We show that, contrary to selection, the estimator has unusual properties because the observed information matrix can explode in finite time whereupon the recombination parameter is learned without error. We also show that the recombination estimator is robust to the presence of selection in the sense that incorporating selection into the model leaves the estimator unchanged. We study the properties of the estimator by simulation and show that its distribution can be quite sensitive to the underlying mutation rates.


Asunto(s)
Evolución Biológica , Recombinación Genética , Haplotipos , Simulación por Computador , Modelos Genéticos
6.
Ecol Lett ; 25(1): 52-64, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34708508

RESUMEN

Climate change is disproportionately impacting mountain ecosystems, leading to large reductions in winter snow cover, earlier spring snowmelt and widespread shrub expansion into alpine grasslands. Yet, the combined effects of shrub expansion and changing snow conditions on abiotic and biotic soil properties remains poorly understood. We used complementary field experiments to show that reduced snow cover and earlier snowmelt have effects on soil microbial communities and functioning that persist into summer. However, ericaceous shrub expansion modulates a number of these impacts and has stronger belowground effects than changing snow conditions. Ericaceous shrub expansion did not alter snow depth or snowmelt timing but did increase the abundance of ericoid mycorrhizal fungi and oligotrophic bacteria, which was linked to decreased soil respiration and nitrogen availability. Our findings suggest that changing winter snow conditions have cross-seasonal impacts on soil properties, but shifts in vegetation can modulate belowground effects of future alpine climate change.


Asunto(s)
Ecosistema , Nieve , Cambio Climático , Pradera , Estaciones del Año , Suelo
7.
J Cardiovasc Electrophysiol ; 33(4): 725-730, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35066954

RESUMEN

INTRODUCTION: Transvenous implantable cardioverter-defibrillators (TV-ICD) infection is a serious complication that frequently requires complete device removal for attempted cure, which can be associated with patient morbidity and mortality. The objective of this study is to assess mortality risk associated with TV-ICD infection in a large Medicare population with de novo TV-ICD implants. METHODS: A survival analysis was conducted using 100% fee-for-service Medicare facility-level claims data to identify patients who underwent de novo TV-ICD implantation between 7/2016 and 1/2018. TV-ICD infection within 2 years of implantation was identified using International Classification of Disease, 10th Edition and current procedural terminology codes. Baseline patient risk factors associated with mortality were identified using the Charlson Comorbidity Index categories. Infection was treated as a time-dependent variable in a multivariate Cox proportional hazards model to account for immortal time bias. RESULTS: Among 26,742 Medicare patients with de novo TV-ICD, 518 (1.9%) had a device-related infection. The overall number of decedents was 4721 (17.7%) over 2 years, with 4555 (17%) in the noninfection group and 166 (32%) in the infection group. After adjusting for baseline patient demographic characteristics and various comorbidities, the presence of TV-ICD infection was associated with an increase of 2.4 (95% CI: 2.08-2.85) times in the mortality hazard ratio. CONCLUSION: The rate of TV-ICD infection and associated mortality in a large, real-world Medicare population is noteworthy. The positive association between device-related infection and risk of mortality further highlights the need to reduce infections.


Asunto(s)
Desfibriladores Implantables , Anciano , Desfibriladores Implantables/efectos adversos , Cardioversión Eléctrica , Humanos , Medicare , Infecciones Relacionadas con Prótesis/epidemiología , Infecciones Relacionadas con Prótesis/etiología , Infecciones Relacionadas con Prótesis/mortalidad , Estudios Retrospectivos , Resultado del Tratamiento , Estados Unidos/epidemiología
8.
Circ Res ; 125(12): 1055-1066, 2019 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-31630621

RESUMEN

RATIONALE: The ubiquitin-editing protein A20 in dendritic cells (DCs) suppresses NF-κB (nuclear factor-κB) signaling and constrains DC-mediated T-cell stimulation, but the role of A20 in modulating the hypertensive response requires elucidation. OBJECTIVE: Here, we tested the hypothesis that A20 in CD11c-expressing myeloid cells mitigates Ang II (angiotensin II)-induced hypertension by limiting renal T-cell activation. METHODS AND RESULTS: Mice with heterozygous deletion of A20 in CD11c-expressing myeloid cells (DC ACT[Cd11c-Cre+A20flox/wt]) have spontaneous DC activation but have normal baseline blood pressures. In response to low-dose chronic Ang II infusion, DC ACT mice compared with WT (wild type) controls had an exaggerated hypertensive response and augmented proportions of CD62LloCD44hi effector memory T lymphocytes in the kidney lymph node. After 10 days of Ang II, DC ACT kidneys had increased numbers of memory effector CD8+, but not CD4+ T cells, compared with WTs. Moreover, the expressions of TNF-α (tumor necrosis factor-α) and IFN-γ (interferon-γ) were upregulated in the DC ACT renal CD8+ T cells but not CD4+ T cells. Saline challenge testing revealed enhanced renal fluid retention in the DC ACT mice. DC ACT kidneys showed augmented protein expression of γ-epithelial sodium channel and NHE3 (sodium-hydrogen antiporter 3). DC ACT mice also had greater reductions in renal blood flow following acute injections with Ang II and enhanced oxidant stress in the vasculature as evidenced by higher circulating levels of malondialdehyde compared with WT controls. To directly test whether enhanced T-cell activation in the DC ACT cohort was responsible for their exaggerated hypertensive response, we chronically infused Ang II into lymphocyte-deficient DC ACT Rag1 (recombination activating protein 1)-deficient (Rag1-/-) mice and WT (Cd11c-Cre-A20flox/wt) Rag1-/- controls. The difference in blood pressure elevation accruing from DC activation was abrogated on the Rag1-/- strain. CONCLUSIONS: Following stimulation of the renin-angiotensin system, A20 suppresses DC activation and thereby mitigates T-cell-dependent blood pressure elevation.


Asunto(s)
Células Dendríticas/metabolismo , Hipertensión/metabolismo , Riñón/metabolismo , Células Mieloides/metabolismo , Linfocitos T/metabolismo , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/deficiencia , Animales , Células Cultivadas , Células Dendríticas/inmunología , Hipertensión/inmunología , Hipertensión/prevención & control , Riñón/citología , Riñón/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Células Mieloides/inmunología , Linfocitos T/inmunología , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa/inmunología
9.
Am J Pathol ; 189(5): 981-988, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31000207

RESUMEN

Most forms of chronic kidney disease culminate in renal fibrosis that heralds organ failure. In contrast to the protective effects of globally blocking type 1 angiotensin (AT1) receptors throughout the body, activating AT1 receptors directly on immune cells may serve protective functions. However, the effects of stimulating the T-cell AT1 receptor on the progression of renal fibrosis remain unknown. In this study, mice with T-cell-specific deletion of the dominant murine AT1 receptor isoform Lck-Cre Agtraflox/flox [total knockout (TKO)] and wild-type (WT) controls were subjected to the unilateral ureteral obstruction model of kidney fibrosis. Compared with WT controls, obstructed kidneys from TKO mice at day 14 had increased collagen 1 deposition. CD4+ T cells, CD11b+Ly6Chi myeloid cells, and mRNA levels of Th1 inflammatory cytokines are elevated in obstructed TKO kidneys, suggesting that augmented Th1 responses in the TKO mice may exaggerate renal fibrosis by driving proinflammatory macrophage differentiation. In turn, T-bet deficient (T-bet knockout) mice lacking Th1 responses have attenuated collagen deposition after unilateral ureteral obstruction. We conclude that activating the AT1 receptor on T cells mitigates renal fibrogenesis by inhibiting Th1 differentiation and renal accumulation of profibrotic macrophages.


Asunto(s)
Fibrosis/prevención & control , Inflamación/prevención & control , Enfermedades Renales/prevención & control , Receptor de Angiotensina Tipo 1/fisiología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Animales , Células Cultivadas , Modelos Animales de Enfermedad , Fibrosis/inmunología , Fibrosis/metabolismo , Fibrosis/patología , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/patología , Enfermedades Renales/inmunología , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Masculino , Ratones , Ratones Noqueados , Linfocitos T/patología
10.
J Cardiovasc Electrophysiol ; 31(2): 503-511, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31916328

RESUMEN

BACKGROUND: Cardiac implantable electronic device transvenous (TV) lead reoperations are projected to increase, and robust economic data are needed to assess the resulting financial impact and the cost-effectiveness of prevention and treatment strategies. This study estimates Medicare costs, and describes patterns of complications, in patients who underwent TV lead reoperation. METHODS AND RESULTS: Medicare data (2010-2014) were used to identify patients who underwent TV lead reoperation. Cumulative costs to Medicare, and rates of infection and mechanical complications were calculated from 180 days before, to 180 days after, lead reoperation. Multivariate analysis was used to estimate adjusted costs, and to examine the impact of complications on medical resource use and costs. There were 1691 patients, 63.2% of whom underwent inpatient lead reoperation. Overall, the mean age was 78.2 years, 39.6% were female, and 92.3% were white. The mean cumulative cost was $36 199 (95% confidence interval [CI], $31 864-$40 535) for TV lead repositioning, $27 701 (95% CI, $19 869-$35 534) for repair, and $54 442 (95% CI, $51 651-$57 233) for removal. Underlying infection was associated with increased odds of inpatient reoperation and of lead removal, as well as longer length of stay and higher costs. CONCLUSIONS: The economic consequences of TV lead reoperation are substantial. Strategies aimed at reducing reoperation, particularly lead removal, are likely to result in considerable cost offsets.


Asunto(s)
Desfibriladores Implantables/economía , Remoción de Dispositivos/efectos adversos , Remoción de Dispositivos/economía , Costos de la Atención en Salud , Recursos en Salud/economía , Marcapaso Artificial/economía , Complicaciones Posoperatorias/economía , Complicaciones Posoperatorias/terapia , Anciano , Anciano de 80 o más Años , Remoción de Dispositivos/mortalidad , Femenino , Humanos , Tiempo de Internación/economía , Masculino , Medicare/economía , Complicaciones Posoperatorias/mortalidad , Reoperación/efectos adversos , Reoperación/economía , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos
11.
J Am Soc Nephrol ; 30(10): 1925-1938, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31337692

RESUMEN

BACKGROUND: Polarized macrophage populations can orchestrate both inflammation of the kidney and tissue repair during CKD. Proinflammatory M1 macrophages initiate kidney injury, but mechanisms through which persistent M1-dependent kidney damage culminates in fibrosis require elucidation. Krüppel-like factor 4 (KLF4), a zinc-finger transcription factor that suppresses inflammatory signals, is an essential regulator of macrophage polarization in adipose tissues, but the effect of myeloid KLF4 on CKD progression is unknown. METHODS: We used conditional mutant mice lacking KLF4 or TNFα (KLF4's downstream effector) selectively in myeloid cells to investigate macrophage KLF4's role in modulating CKD progression in two models of CKD that feature robust macrophage accumulation, nephrotoxic serum nephritis, and unilateral ureteral obstruction. RESULTS: In these murine CKD models, KLF4 deficiency in macrophages infiltrating the kidney augmented their M1 polarization and exacerbated glomerular matrix deposition and tubular epithelial damage. During the induced injury in these models, macrophage-specific KLF4 deletion also exacerbated kidney fibrosis, with increased levels of collagen 1 and α-smooth muscle actin in the injured kidney. CD11b+Ly6Chi myeloid cells isolated from injured kidneys expressed higher levels of TNFα mRNA versus wild-type controls. In turn, mice bearing macrophage-specific deletion of TNFα exhibited decreased glomerular and tubular damage and attenuated kidney fibrosis in the models. Moreover, treatment with the TNF receptor-1 inhibitor R-7050 during nephrotoxic serum nephritis reduced damage, fibrosis, and necroptosis in wild-type mice and mice with KLF4-deficient macrophages, and abrogated the differences between the two groups in these parameters. CONCLUSIONS: These data indicate that macrophage KLF4 ameliorates CKD by mitigating TNF-dependent injury and fibrosis.


Asunto(s)
Enfermedades Renales/etiología , Riñón/patología , Factores de Transcripción de Tipo Kruppel/fisiología , Macrófagos/fisiología , Factor de Necrosis Tumoral alfa/fisiología , Animales , Fibrosis/etiología , Factor 4 Similar a Kruppel , Masculino , Ratones , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
12.
J Am Soc Nephrol ; 30(9): 1674-1685, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31315922

RESUMEN

BACKGROUND: Following an acute insult, macrophages regulate renal fibrogenesis through the release of various factors that either encourage the synthesis of extracellular matrix synthesis or the degradation of matrix via endocytosis, proteolysis, or both. However, the roles of infiltrating versus resident myeloid cells in these opposing processes require elucidation. The transcription factor Twist1 controls diverse essential cellular functions through induction of several downstream targets, including matrix metalloproteinases (MMPs). In macrophages, Twist1 can influence patterns of cytokine generation, but the role of macrophage Twist1 in renal fibrogenesis remains undefined. METHODS: To study Twist1 functions in different macrophage subsets during kidney scar formation, we used two conditional mutant mouse models in which Twist1 was selectively ablated either in infiltrating, inflammatory macrophages or in resident tissue macrophages. We assessed fibrosis-related parameters, matrix metallopeptidase 13 (MMP13, or collagen 3, which catalyzes collagen degradation), inflammatory cytokines, and other factors in these Twist1-deficient mice compared with wild-type controls after subjecting the animals to unilateral ureteral obstruction. We also treated wild-type and Twist1-deficient mice with an MMP13 inhibitor after unilateral ureteral obstruction. RESULTS: Twist1 in infiltrating inflammatory macrophages but not in resident macrophages limited kidney fibrosis after ureteral obstruction by driving extracellular matrix degradation. Moreover, deletion of Twist1 in infiltrating macrophages attenuated the expression of MMP13 in CD11b+Ly6Clo myeloid cells. Inhibition of MMP13 abrogated the protection from renal fibrosis afforded by macrophage Twist1. CONCLUSIONS: Twist1 in infiltrating myeloid cells mitigates interstitial matrix accumulation in the injured kidney by promoting MMP13 production, which drives extracellular matrix degradation. These data highlight the complex cell-specific actions of Twist1 in the pathogenesis of kidney fibrosis.


Asunto(s)
Matriz Extracelular/metabolismo , Enfermedades Renales/metabolismo , Riñón/metabolismo , Riñón/patología , Macrófagos/metabolismo , Metaloproteinasa 13 de la Matriz/metabolismo , Proteína 1 Relacionada con Twist/metabolismo , Actinas/metabolismo , Animales , Benzofuranos/farmacología , Receptor 1 de Quimiocinas CX3C/metabolismo , Colágeno Tipo I/metabolismo , Modelos Animales de Enfermedad , Fibrosis , Expresión Génica , Hidroxiprolina/metabolismo , Enfermedades Renales/etiología , Enfermedades Renales/patología , Macrófagos Peritoneales/metabolismo , Masculino , Metaloproteinasa 13 de la Matriz/genética , Inhibidores de la Metaloproteinasa de la Matriz/farmacología , Ratones , Morfolinas/farmacología , Células Mieloides/enzimología , Proteína 1 Relacionada con Twist/genética , Obstrucción Ureteral/complicaciones
13.
Nurs Philos ; 21(3): e12301, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32458581

RESUMEN

This article describes how an empirically supported theory of human behaviour, perceptual control theory, can be used to advance nursing practice and improve health outcomes for people who are accessing nursing care. Nursing often takes a pragmatic approach to the delivery of care, with an emphasis on doing what appears to work. This focus on pragmatism can sometimes take precedence over any consideration of the underlying theoretical assumptions that inform decisions to take one particular approach over another or the mechanisms through which nursing interventions have their effects. For nursing to develop as a profession, there needs to be an increased focus on the core principles that underpin the delivery of care. In addition to understanding what works, nurses must develop their understanding of how and why particular approaches work or do not work. Understanding the fundamental principles that underpin nurses' actions will lead to more efficient and effective approaches to the delivery of nursing care. It will also enable nurses to maximize those elements of their practice that are most beneficial for people and minimize other activities that either have little effect or actually lead to worse outcomes. In this article, we will propose that the phenomenon of control is fundamental to human health. Perceptual control theory provides a coherent theoretical framework that enables us to understand the phenomenon of control through a functional model of human behaviour. People are healthy when their neurochemical, physiological, biological, psychological and social states are all controlled satisfactorily. We will explain the implications of understanding health as control throughout the paper. From this perspective, we will argue that the aim of nurses and nursing should be to support people to maintain or recover control over those aspects of their lives that are important and meaningful to them.


Asunto(s)
Proceso de Enfermería/normas , Evaluación de Resultado en la Atención de Salud/métodos , Resultado del Tratamiento , Humanos , Modelos de Enfermería , Evaluación de Resultado en la Atención de Salud/normas
14.
Kidney Int ; 96(6): 1308-1319, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31585741

RESUMEN

Wnt/ß-catenin signaling is essential in the pathogenesis of renal fibrosis. We previously reported inhibition of the Wnt O-acyl transferase porcupine, required for Wnt secretion, dramatically attenuates kidney fibrosis in the murine unilateral ureteral obstruction model. Here, we investigated the tissue-specific contributions of porcupine to renal fibrosis and inflammation in ureteral obstruction using mice with porcupine deletion restricted to the kidney tubular epithelium or infiltrating myeloid cells. Obstruction of the ureter induced the renal mRNA expression of porcupine and downstream targets, ß-catenin, T-cell factor, and lymphoid enhancer factor in wild type mice. Renal tubular specific deficiency of porcupine reduced the expression of collagen I and other fibrosis markers in the obstructed kidney. Moreover, kidneys from obstructed mice with tubule-specific porcupine deficiency had reduced macrophage accumulation with attenuated expression of myeloid cytokine and chemokine mRNA. In co-culture with activated macrophages, renal tubular cells from tubular-specific porcupine knockout mice had blunted induction of fibrosis mediators compared with wild type renal tubular cells. In contrast, macrophages from macrophage-specific porcupine deficient mice in co-culture with wild type renal tubular cells had markedly enhanced expression of pro-fibrotic cytokines compared to wild type macrophages. Consequently, porcupine deletion specifically within macrophages augmented renal scar formation following ureteral obstruction. Thus, our experiments suggest a benefit of interrupting Wnt secretion specifically within the kidney epithelium while preserving Wnt O-acylation in infiltrating myeloid cells during renal fibrogenesis.


Asunto(s)
Aciltransferasas/metabolismo , Proteínas de la Membrana/metabolismo , Nefroesclerosis/metabolismo , Vía de Señalización Wnt , Animales , Quimiocinas/metabolismo , Femenino , Fibrosis , Túbulos Renales/metabolismo , Túbulos Renales/patología , Macrófagos/metabolismo , Masculino , Ratones , Ratones Noqueados , Células Mieloides/metabolismo , Nefroesclerosis/etiología , Obstrucción Ureteral
15.
Glob Chang Biol ; 25(12): 3996-4007, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31386782

RESUMEN

Soil organic matter (SOM) is an indicator of sustainable land management as stated in the global indicator framework of the United Nations Sustainable Development Goals (SDG Indicator 15.3.1). Improved forecasting of future changes in SOM is needed to support the development of more sustainable land management under a changing climate. Current models fail to reproduce historical trends in SOM both within and during transition between ecosystems. More realistic spatio-temporal SOM dynamics require inclusion of the recent paradigm shift from SOM recalcitrance as an 'intrinsic property' to SOM persistence as an 'ecosystem interaction'. We present a soil profile, or pedon-explicit, ecosystem-scale framework for data and models of SOM distribution and dynamics which can better represent land use transitions. Ecosystem-scale drivers are integrated with pedon-scale processes in two zones of influence. In the upper vegetation zone, SOM is affected primarily by plant inputs (above- and belowground), climate, microbial activity and physical aggregation and is prone to destabilization. In the lower mineral matrix zone, SOM inputs from the vegetation zone are controlled primarily by mineral phase and chemical interactions, resulting in more favourable conditions for SOM persistence. Vegetation zone boundary conditions vary spatially at landscape scales (vegetation cover) and temporally at decadal scales (climate). Mineral matrix zone boundary conditions vary spatially at landscape scales (geology, topography) but change only slowly. The thicknesses of the two zones and their transport connectivity are dynamic and affected by plant cover, land use practices, climate and feedbacks from current SOM stock in each layer. Using this framework, we identify several areas where greater knowledge is needed to advance the emerging paradigm of SOM dynamics-improved representation of plant-derived carbon inputs, contributions of soil biota to SOM storage and effect of dynamic soil structure on SOM storage-and how this can be combined with robust and efficient soil monitoring.


Asunto(s)
Ecosistema , Suelo , Carbono , Clima , Plantas
16.
Philos Trans A Math Phys Eng Sci ; 377(2157): 20190033, 2019 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-31522640

RESUMEN

In quantum physics, the term 'contextual' can be used in more than one way. One usage, here called 'Bell contextual' since the idea goes back to Bell, is that if A, B and C are three quantum observables, with A compatible (i.e. commuting) with B and also with C, whereas B and C are incompatible, a measurement of A might yield a different result (indicating that quantum mechanics is contextual) depending upon whether A is measured along with B (the {A, B} context) or with C (the {A, C} context). An analysis of what projective quantum measurements measure shows that quantum theory is Bell non-contextual: the outcome of a particular A measurement when A is measured along with B would have been exactly the same if A had, instead, been measured along with C. A different definition, here called 'globally (non)contextual' refers to whether or not there is (non-contextual) or is not (contextual) a single joint probability distribution that simultaneously assigns probabilities in a consistent manner to the outcomes of measurements of a certain collection of observables, not all of which are compatible. A simple example shows that such a joint probability distribution can exist even in a situation where the measurement probabilities cannot refer to properties of a quantum system, and hence lack physical significance, even though mathematically well defined. It is noted that the quantum sample space, a projective decomposition of the identity, required for interpreting measurements of incompatible properties in different runs of an experiment using different types of apparatus, has a tensor product structure, a fact sometimes overlooked. This article is part of the theme issue 'Contextuality and probability in quantum mechanics and beyond'.

17.
J Math Biol ; 79(6-7): 2315-2342, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31531705

RESUMEN

The transition distribution of a sample taken from a Wright-Fisher diffusion with general small mutation rates is found using a coalescent approach. The approximation is equivalent to having at most one mutation in the coalescent tree of the sample up to the most recent common ancestor with additional mutations occurring on the lineage from the most recent common ancestor to the time origin if complete coalescence occurs before the origin. The sampling distribution leads to an approximation for the transition density in the diffusion with small mutation rates. This new solution has interest because the transition density in a Wright-Fisher diffusion with general mutation rates is not known.


Asunto(s)
Flujo Genético , Genética de Población/métodos , Modelos Genéticos , Tasa de Mutación , Frecuencia de los Genes
18.
J Math Biol ; 78(4): 1211-1224, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30426201

RESUMEN

The stationary distribution of a sample taken from a Wright-Fisher diffusion with general small mutation rates is found using a coalescent approach. The approximation is equivalent to having at most one mutation in the coalescent tree to the first order in the rates. The sample probabilities characterize an approximation for the stationary distribution from the Wright-Fisher diffusion. The approach is different from Burden and Tang (Theor Popul Biol 112:22-32, 2016; Theor Popul Biol 113:23-33, 2017) who use a probability flux argument to obtain the same results from a forward diffusion generator equation. The solution has interest because the solution is not known when rates are not small. An analogous solution is found for the configuration of alleles in a general exchangeable binary coalescent tree. In particular an explicit solution is found for a pure birth process tree when individuals reproduce at rate [Formula: see text].


Asunto(s)
Modelos Genéticos , Tasa de Mutación , Alelos , Animales , Biología Computacional , Frecuencia de los Genes , Genética de Población , Cadenas de Markov , Conceptos Matemáticos , Probabilidad
19.
Int J Qual Health Care ; 31(2): 75-88, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29912446

RESUMEN

PURPOSE: Overlooking other conditions during cancer could undermine gains associated with early detection and improved cancer treatment. We conducted a systematic review on the quality of diabetes care in cancer. DATA SOURCES: Systematic searches of Medline and Embase, from 1996 to present, were conducted to identify studies on the quality of diabetes care in patients diagnosed with cancer. STUDY SELECTION: Studies were selected if they met the following criteria: longitudinal or cross-sectional observational study; population consisted of diabetes patients; exposure consisted of cancer of any type and outcomes consisted of diabetes quality of care indicators, including healthcare visits, monitoring and testing, control of biologic parameters, or use of diabetes and other related medications. DATA EXTRACTION: Structured data collection forms were developed to extract information on the study design and four types of quality indicators: physician visits, exams or diabetes education (collectively 'healthcare visits'); monitoring and testing; control of biologic parameters; and medication use and adherence. RESULTS OF DATA SYNTHESIS: There were 15 studies from five countries. There was no consistent evidence that cancer was associated with fewer healthcare visits, lower monitoring and testing of biologic parameters or poorer control of biologic parameters, including glucose. However, the weight of the evidence suggests cancer was associated with lower adherence to diabetes medications and other medications, such as anti-hypertensives and cholesterol-lowering agents. CONCLUSION: Evidence indicates cancer is associated with poorer adherence to diabetes and other medications. Further primary research could clarify cancer's impact on other diabetes quality indicators.


Asunto(s)
Diabetes Mellitus/terapia , Manejo de la Enfermedad , Neoplasias , Calidad de la Atención de Salud/estadística & datos numéricos , Humanos , Hipoglucemiantes/uso terapéutico , Cumplimiento de la Medicación/estadística & datos numéricos
20.
Qual Health Res ; 29(1): 107-123, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30066602

RESUMEN

In this study, we aim to increase our understanding of the self-reported sources of distress among people who have experienced first-episode psychosis. Following a systematic literature search, 33 relevant studies containing first-person accounts of first-episode psychosis were identified, which were synthesized using thematic analysis. Two interrelated superordinate themes were identified: intrapersonal distress and interpersonal distress. Participants reported multiple, diverse, and multifaceted sources of distress across both themes. These were substantially different from those routinely recognized and targeted in clinical practice. This review suggests that practitioners who maintain a stance of genuine curiosity about the potential sources of distress for this population will be perceived as more helpful. The findings also highlight the importance of being service user-led when planning and delivering mental health care. Additional clinical and research implications are discussed.


Asunto(s)
Trastornos Psicóticos/psicología , Investigación Cualitativa , Estrés Psicológico/etiología , Estrés Psicológico/psicología , Actitud del Personal de Salud , Conflicto Psicológico , Estado de Salud , Humanos , Relaciones Interpersonales , Teoría Psicológica , Trauma Psicológico/epidemiología , Trauma Psicológico/psicología , Trastornos Psicóticos/epidemiología , Autoimagen , Estigma Social , Estrés Psicológico/epidemiología
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