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1.
Cell Rep ; 39(13): 111012, 2022 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-35767962

RESUMEN

Ovarian cancer (OC) is the most lethal gynecological malignancy, with aggressive metastatic disease responsible for the majority of OC-related deaths. In particular, OC tumors preferentially metastasize to and proliferate rapidly in the omentum. Here, we show that metastatic OC cells experience increased oxidative stress in the omental microenvironment. Metabolic reprogramming, including upregulation of the pentose phosphate pathway (PPP), a key cellular redox homeostasis mechanism, allows OC cells to compensate for this challenge. Inhibition of glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the PPP, reduces tumor burden in pre-clinical models of OC, suggesting that this adaptive metabolic dependency is important for OC omental metastasis.


Asunto(s)
Glucosafosfato Deshidrogenasa , Neoplasias Ováricas , Carcinoma Epitelial de Ovario , Femenino , Glucosafosfato Deshidrogenasa/metabolismo , Humanos , Epiplón/metabolismo , Estrés Oxidativo , Vía de Pentosa Fosfato , Microambiente Tumoral
3.
Am J Hum Biol ; 34 Suppl 1: e23690, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34664346

RESUMEN

BACKGROUND: Quality mentorship is crucial for long-term success in academia and overall job satisfaction. Unfortunately, formal mentorship training is lacking, and there is little recourse for failed mentor-mentee relationships. METHODS: We performed a literature review to understand the current state of mentorship research with a focus on: (1) what mentorship is and why it is important for success; (2) establishing mentor-mentee relationships; and (3) the role of diversity, equity, and inclusion. RESULTS: From the literature review, we compiled a number of mentorship recommendations for individuals, departments, institutions, and professional associations. These recommendations focus on building a mentorship network, establishing formalized mentorship training, how to build a productive and mutually beneficial mentor-mentee relationship, and instituting a system of mentorship accountability. CONCLUSION: We hope that by centralizing this information and providing a list of resources and actionable recommendations we inspire and encourage others to make meaningful changes in their approach to mentorship to create a more kind, caring, and equitable environment in which to conduct our work.


Asunto(s)
Tutoría , Mentores , Humanos
4.
Mol Genet Metab ; 133(3): 269-276, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34083142

RESUMEN

INTRODUCTION: Liver Glycogen Storage Disease IX is a rare metabolic disorder of glycogen metabolism caused by deficiency of the phosphorylase kinase enzyme (PhK). Variants in the PHKG2 gene, encoding the liver-specific catalytic γ2 subunit of PhK, are associated with a liver GSD IX subtype known as PHKG2 GSD IX or GSD IX γ2. There is emerging evidence that patients with GSD IX γ2 can develop severe and progressive liver disease, yet research regarding the disease has been minimal to date. Here we characterize the first mouse model of liver GSD IX γ2. METHODS: A Phkg2-/- mouse model was generated via targeted removal of the Phkg2 gene. Knockout (Phkg2-/-, KO) and wild type (Phkg2+/+, WT) mice up to 3 months of age were compared for morphology, Phkg2 transcription, PhK enzyme activity, glycogen content, histology, serum liver markers, and urinary glucose tetrasaccharide Glcα1-6Glcα1-4Glcα1-4Glc (Glc4). RESULTS: When compared to WT controls, KO mice demonstrated significantly decreased liver PhK enzyme activity, increased liver: body weight ratio, and increased glycogen in the liver, with no glycogen accumulation observed in the brain, quadricep, kidney, and heart. KO mice demonstrated elevated liver blood markers as well as elevated urine Glc4, a commonly used biomarker for glycogen storage disease. KO mice demonstrated features of liver structural damage. Hematoxylin & Eosin and Masson's Trichrome stained KO mice liver histology slides revealed characteristic GSD hepatocyte architectural changes and early liver fibrosis, as have been reported in liver GSD patients. DISCUSSION: This study provides the first evidence of a mouse model that recapitulates the liver-specific pathology of patients with GSD IX γ2. The model will provide the first platform for further study of disease progression in GSD IX γ2 as well as for the evaluation of novel therapeutics.


Asunto(s)
Modelos Animales de Enfermedad , Enfermedad del Almacenamiento de Glucógeno/fisiopatología , Glucógeno/metabolismo , Hepatopatías/fisiopatología , Hígado/fisiopatología , Ratones , Fosforilasa Quinasa/genética , Animales , Femenino , Enfermedad del Almacenamiento de Glucógeno/genética , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilasa Quinasa/deficiencia
5.
Nat Ecol Evol ; 5(7): 1003-1010, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33972737

RESUMEN

The 2019-20 wildfires in eastern Australia presented a globally important opportunity to evaluate the respective roles of climatic drivers and natural and anthropogenic disturbances in causing high-severity fires. Here, we show the overwhelming dominance of fire weather in causing complete scorch or consumption of forest canopies in natural and plantation forests in three regions across the geographic range of these fires. Sampling 32% (2.35 Mha) of the area burnt we found that >44% of the native forests suffered severe canopy damage. Past logging and wildfire disturbance in natural forests had a very low effect on severe canopy damage, reflecting the limited extent logged in the last 25 years (4.5% in eastern Victoria, 5.3% in southern New South Wales (NSW) and 7.8% in northern NSW). The most important variables determining severe canopy damage were broad spatial factors (mostly topographic) followed by fire weather. Timber plantations affected by fire were concentrated in NSW and 26% were burnt by the fires and >70% of the NSW plantations suffered severe canopy damage showing that this intensive means of wood production is extremely vulnerable to wildfire. The massive geographic scale and severity of these Australian fires is best explained by extrinsic factors: an historically anomalous drought coupled with strong, hot dry westerly winds that caused uninterrupted, and often dangerous, fire weather over the entire fire season.


Asunto(s)
Eucalyptus , Incendios Forestales , Bosques , Nueva Gales del Sur , Victoria
6.
Mol Genet Metab ; 131(3): 299-305, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33317799

RESUMEN

INTRODUCTION: Liver Glycogen Storage Disease Type IX (GSD IX) is one of the most common forms of GSD. It is caused by a deficiency in enzyme phosphorylase kinase (PhK), a complex, hetero-tetrameric enzyme comprised of four subunits - α, ß, γ, and δ - each with tissue specific isoforms encoded by different genes. Until the recent availability of gene panels and exome sequencing, the diagnosis of liver GSD IX did not allow for differentiation of these subtypes. This study presents the first comprehensive literature review for liver GSD IX subtypes - GSD IX α2, ß, and γ2. We aim to better characterize the natural history of liver GSD IX and further investigate if there are subtype-specific differences in clinical presentation. METHODS: A comprehensive literature review was performed with the help of a medical librarian at Duke University Medical Center to gather all published patients of liver GSD IX. Our refined search yielded 74 articles total. Available patient data were compiled into an excel spreadsheet. Data were analyzed via descriptive statistics. The number of patients with specific symptoms were individually summed and reported as a percentage of the total number of patients for which data were available or were averaged and reported as a mean numerical value. Published pathology reports were scored using the International Association of the Study of the Liver Scale. RESULTS: There were a total of 183 GSD IX α2 patients, 17 GSD IX ß patients, and 30 GSD IX γ2 patients. Average age at diagnosis was 4 years for GSD IX α2 patients, 2.34 years for GSD IX ß patients, and 1.81 years for GSD IX γ2 patients. Hepatomegaly was reported in 164/176 (93.2%) of GSD IX α2 patients, 16/17 (94.1%) of GSD IX ß patients, and 30/30 (100%) of GSD IX γ2 patients. Fasting hypoglycemia was reported in 53/121 (43.8%) of GSD IX α2 patients, 8/16 (50%) of GSD IX ß patients, and 18/19 (94.7%) of GSD IX γ2 patients. Liver biopsy pathology reports were available and interpreted for 46 GSD IX α2 patients, 3 GSD IX ß patients, and 24 GSD IX γ2 patients. 22/46 (47.8%) GSD IX α2 patients, 1/3 (33.3%) GSD IX ß patients, and 23/24 (95.8%) GSD IX γ2 patients with available pathology reports documented either some degree of fibrosis or cirrhosis. CONCLUSION: Our comprehensive review demonstrates quantitatively that the clinical presentation of GSD IX γ2 patients is more severe than that of GSD IX α2 or ß patients. However, our study also shows the existence of a severe phenotype in GSD IX α2, evidenced by early onset liver pathology in conjunction with clinical symptoms. There is need for a more robust natural history study to better understand the variability in liver pathophysiology within liver GSD IX; in addition, further study of mutations and gene mapping could bring a better understanding of the relationship between genotype and clinical presentation.


Asunto(s)
Enfermedades Genéticas Ligadas al Cromosoma X/epidemiología , Enfermedad del Almacenamiento de Glucógeno/epidemiología , Fosforilasa Quinasa/genética , Preescolar , Femenino , Enfermedades Genéticas Ligadas al Cromosoma X/diagnóstico , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Enfermedades Genéticas Ligadas al Cromosoma X/metabolismo , Genotipo , Enfermedad del Almacenamiento de Glucógeno/diagnóstico , Enfermedad del Almacenamiento de Glucógeno/genética , Enfermedad del Almacenamiento de Glucógeno/metabolismo , Humanos , Lactante , Hígado/metabolismo , Hígado/patología , Masculino , Mutación/genética , Subunidades de Proteína/genética
7.
Mov Disord ; 35(10): 1868-1873, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32633875

RESUMEN

BACKGROUND: The mutations of KCNMA1 BK-type K+ channel have been identified in patients with various movement disorders. The underlying pathophysiology and corresponding therapeutics are lacking. OBJECTIVES: To report our clinical and biophysical characterizations of a novel de novo KCNMA1 variant, as well as an effective therapy for the patient's dystonia-atonia spells. METHODS: Combination of phenotypic characterization, therapy, and biophysical characterization of the patient and her mutation. RESULTS: The patient had >100 dystonia-atonia spells per day with mild cerebellar atrophy. She also had autism spectrum disorder, intellectual disability, and attention deficit hyperactivity disorder. Whole-exome sequencing identified a heterozygous de novo BK N536H mutation. Our biophysical characterization demonstrates that N536H is a gain-of-function mutation with markedly enhanced voltage-dependent activation. Remarkably, administration of dextroamphetamine completely suppressed the dystonia-atonia spells. CONCLUSIONS: BK N536H is a gain-of-function that causes dystonia and other neurological symptoms. Our stimulant therapy opens a new avenue to mitigate KCNMA1-linked movement disorders. © 2020 International Parkinson and Movement Disorder Society.


Asunto(s)
Trastorno del Espectro Autista , Distonía , Discapacidad Intelectual , Distonía/tratamiento farmacológico , Distonía/genética , Femenino , Mutación con Ganancia de Función , Humanos , Subunidades alfa de los Canales de Potasio de Gran Conductancia Activados por Calcio/genética , Mutación/genética
8.
Br J Nurs ; 28(5): 307-312, 2019 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-30907659

RESUMEN

BACKGROUND:: health professionals' attitudes towards self-harming behaviour are predominantly negative. Research examining educational interventions to change negative attitudes is limited. AIMS:: this study aimed to provide an educational intervention for student nurses to change negative attitudes around self-harm. METHODS:: attitudes around self-harm and mental health in general were assessed through the Self-Harm Antipathy Scale and the Mental Health Attitude Scale. Fifty-five adult nursing students took part in the 45-minute intervention. This included facts and figures, celebrity stories and personal stories regarding self-harm, all intended to increase understanding. FINDINGS:: after the intervention, attitudes measured by the Self-Harm Antipathy Scale had improved significantly. CONCLUSION:: patients who self-harm will without doubt continue to experience negative attitudes from health professionals. This study shows an educational intervention can change attitudes towards those who self-harm.


Asunto(s)
Actitud del Personal de Salud , Evaluación Educacional , Estigma Social , Estudiantes de Enfermería/psicología , Suicidio , Humanos
9.
J Environ Manage ; 235: 34-41, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30669091

RESUMEN

Considerable investments are made in managing fire risk to human assets, including a growing use of fire behaviour simulation tools to allocate expenditure. Understanding fire risk requires estimation of the likelihood of ignition, spread of the fire and impact on assets. The ability to estimate and predict risk requires both the development of ignition likelihood models and the evaluation of these models in novel environments. We developed models for natural and anthropogenic ignitions in the south-eastern Australian state of Victoria incorporating variables relating to fire weather, terrain and the built environment. Fire weather conditions had a consistently positive effect on the likelihood of ignition, although they contributed much more to lightning (57%) and power transmission (55%) ignitions than the 7 other modelled causes (8-32%). The built environment played an important role in driving anthropogenic ignitions. Housing density was the most important variable in most models and proximity to roads had a consistently positive effect. In contrast, the best model for lightning ignitions included a positive relationship with primary productivity, as represented by annual rainfall. These patterns are broadly consistent with previous ignition modelling studies. The models developed for Victoria were tested in the neighbouring fire prone states of South Australia and Tasmania. The anthropogenic ignition model performed well in South Australia (AUC = 0.969) and Tasmania (AUC = 0.848), whereas the natural ignition model only performed well in South Australia (AUC = 0.972; Tasmania AUC = 0.612). Model performance may have been impaired by much lower lightning ignition rates in South Australia and Tasmania than in Victoria. This study shows that the spatial likelihood of ignition can be reliably predicted based on readily available meteorological and biophysical data. Furthermore, the strong performance of anthropogenic and natural ignition models in novel environments suggests there are some universal drivers of ignition likelihood across south-eastern Australia.


Asunto(s)
Incendios , Relámpago , Incendios Forestales , Humanos , Australia del Sur , Tasmania , Victoria
10.
Sci Total Environ ; 580: 168-177, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28024746

RESUMEN

To protect recreational water users from waterborne pathogen exposure, it is crucial that waterways are monitored for the presence of harmful bacteria. In NYC, a citizen science campaign is monitoring waterways impacted by inputs of storm water and untreated sewage during periods of rainfall. However, the spatial and temporal scales over which the monitoring program can sample are constrained by cost and time, thus hindering the construction of databases that benefit both scientists and citizens. In this study, we first illustrate the scientific value of a citizen scientist monitoring campaign by using the data collected through the campaign to characterize the seasonal variability of sampled bacterial concentration as well as its response to antecedent rainfall. Second, we examine the efficacy of the HyServe Compact Dry ETC method, a lower cost and time-efficient alternative to the EPA-approved IDEXX Enterolert method for fecal indicator monitoring, through a paired sample comparison of IDEXX and HyServe (total of 424 paired samples). The HyServe and IDEXX methods return the same result for over 80% of the samples with regard to whether a water sample is above or below the EPA's recreational water quality criteria for a single sample of 110 enterococci per 100mL. The HyServe method classified as unsafe 90% of the 119 water samples that were classified as having unsafe enterococci concentrations by the more established IDEXX method. This study seeks to encourage other scientists to engage with citizen scientist communities and to also pursue the development of cost- and time-efficient methodologies to sample environmental variables that are not easily collected or analyzed in an automated manner.

11.
J Am Chem Soc ; 137(51): 16098-108, 2015 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-26600089

RESUMEN

Poly(glycerol monomethacrylate)-poly(2-hydroxypropyl methacrylate) diblock copolymer vesicles can be prepared in the form of concentrated aqueous dispersions via polymerization-induced self-assembly (PISA). In the present study, these syntheses are conducted in the presence of varying amounts of silica nanoparticles of approximately 18 nm diameter. This approach leads to encapsulation of up to hundreds of silica nanoparticles per vesicle. Silica has high electron contrast compared to the copolymer which facilitates TEM analysis, and its thermal stability enables quantification of the loading efficiency via thermogravimetric analysis. Encapsulation efficiencies can be calculated using disk centrifuge photosedimentometry, since the vesicle density increases at higher silica loadings while the mean vesicle diameter remains essentially unchanged. Small angle X-ray scattering (SAXS) is used to confirm silica encapsulation, since a structure factor is observed at q ≈ 0.25 nm(-1). A new two-population model provides satisfactory data fits to the SAXS patterns and allows the mean silica volume fraction within the vesicles to be determined. Finally, the thermoresponsive nature of the diblock copolymer vesicles enables thermally triggered release of the encapsulated silica nanoparticles simply by cooling to 0-10 °C, which induces a morphological transition. These silica-loaded vesicles constitute a useful model system for understanding the encapsulation of globular proteins, enzymes, or antibodies for potential biomedical applications. They may also serve as an active payload for self-healing hydrogels or repair of biological tissue. Finally, we also encapsulate a model globular protein, bovine serum albumin, and calculate its loading efficiency using fluorescence spectroscopy.


Asunto(s)
Nanopartículas , Polímeros/química , Dióxido de Silicio/química , Cristalografía por Rayos X , Microscopía Electrónica de Transmisión , Polimerizacion , Dispersión del Ángulo Pequeño , Termogravimetría
12.
PLoS One ; 9(4): e95053, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24743447

RESUMEN

Dispersal knowledge is essential for conservation management, and demand is growing. But are we accumulating dispersal knowledge at a pace that can meet the demand? To answer this question we tested for changes in dispersal data collection and use over time. Our systematic review of 655 conservation-related publications compared five topics: climate change, habitat restoration, population viability analysis, land planning (systematic conservation planning) and invasive species. We analysed temporal changes in the: (i) questions asked by dispersal-related research; (ii) methods used to study dispersal; (iii) the quality of dispersal data; (iv) extent that dispersal knowledge is lacking, and; (v) likely consequences of limited dispersal knowledge. Research questions have changed little over time; the same problems examined in the 1990s are still being addressed. The most common methods used to study dispersal were occupancy data, expert opinion and modelling, which often provided indirect, low quality information about dispersal. Although use of genetics for estimating dispersal has increased, new ecological and genetic methods for measuring dispersal are not yet widely adopted. Almost half of the papers identified knowledge gaps related to dispersal. Limited dispersal knowledge often made it impossible to discover ecological processes or compromised conservation outcomes. The quality of dispersal data used in climate change research has increased since the 1990s. In comparison, restoration ecology inadequately addresses large-scale process, whilst the gap between knowledge accumulation and growth in applications may be increasing in land planning. To overcome apparent stagnation in collection and use of dispersal knowledge, researchers need to: (i) improve the quality of available data using new approaches; (ii) understand the complementarities of different methods and; (iii) define the value of different kinds of dispersal information for supporting management decisions. Ambitious, multi-disciplinary research programs studying many species are critical for advancing dispersal research.


Asunto(s)
Ecología/métodos , Ecología/tendencias , Investigación Empírica , Animales , Ecología/historia , Historia del Siglo XX , Historia del Siglo XXI , Humanos
13.
Artículo en Inglés | MEDLINE | ID: mdl-26734206

RESUMEN

Each year approximately 282,000 inpatient falls are reported to the National Patient Safety Agency (NPSA). A significant number result in death, or moderate to severe injury. (1) Research shows that falls may be reduced by 18 to 31% through multi-factorial assessments and interventions. (4) If a fall cannot be prevented, the patient should receive a prompt and effective response to achieve the best possible recovery and avoidance of further falls. Using 'Plan-Do-Study-Act' learning cycles, our aims were to decrease the inpatient falls rate in an Elderly Care ward by 20% and to improve post-fall care. A baseline audit reviewed incident report forms to establish the number of falls per 1000 patient bed days for one calendar year; the baseline falls rate was 14.70 falls per 1000 bed days between November 2010 and October 2011. A care plan to highlight at-risk patients and allow adaptation of care, a 'walking-stick' incentive poster to encourage nursing staff, and post-fall guidelines, were introduced. Feedback sessions with ward staff and a re-audit were organised subsequent to each intervention. Completion of the care plan was monitored to improve compliance. A re-audit at one year was conducted to assess impact. Feedback was positive regarding the interventions. Monthly monitoring of care plans achieved a compliance rate of 89% and highlighted up to 81% of patients were considered high-risk. The inpatient falls rate, re-audited at one year, was 12.44 falls / 1000 patient bed days, November 2011 to October 2012; a 15.4% reduction. This study demonstrates a 15.4% reduction in falls through use of a multi-factorial assessment and care plan and an incentive poster. As we are yet to obtain our initial goal of 20%, implementation and re-audit is ongoing.

14.
Hum Vaccin ; 5(3): 151-7, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19246990

RESUMEN

The disease burden and public health impact of chronic HCV infection continues to be a major problem globally. Current treatment for chronic HCV infection is not effective in all patients and is frequently associated with unacceptable side effects. Clearly a need exists for improved treatments and one such strategy is the use of therapeutic vaccines. Although still not completely understood, emerging data indicate that the generation of CD4(+) and CD8(+) T cells are important for the clearance of HCV. We have developed a prototype vaccine with the HCV Core protein and ISCOMATRIX adjuvant (HCV Core ISCOMATRIX vaccine). ISCOMATRIX vaccines have been shown to induce CD4(+) and CD8(+) T cell responses to a range of antigens in both animal models and in human studies. Additionally, ISCOMATRIX vaccines have been shown to be safe and generally well tolerated in several clinical trials. Preliminary studies demonstrated that the prototype HCV Core ISCOMATRIX vaccine induced strong CD4(+) and CD8(+) T cell responses in monkeys following immunization. Here we show the results of a Phase I placebo controlled, dose escalation clinical study designed to evaluate the safety, tolerability and immunogenicity of the HCV Core ISCOMATRIX vaccine in healthy individuals. The 30 subjects received three immunizations of HCV Core ISCOMATRIX vaccines or placebo vaccine on days 0, 28 and 56. The HCV Core ISCOMATRIX vaccines contained 5, 20 or 50 microg HCV Core protein with 120 mug ISCOMATRIX adjuvant. The adverse events reported were generally mild to moderate in severity, of short duration and self-limiting. The most common adverse events were injection site reactions such as pain and redness as well as myalgia. Antibody responses were detected in all but one of the participants receiving the HCV Core ISCOMATRIX vaccine and there was no indication of a dose response. CD8(+) T cell responses were only detected in two of the eight participants receiving the highest dose. T cell cytokines were detected in 7 of the 8 participants in the highest dose group. The results of this study support the further evaluation of this prototype HCV Core ISCOMATRIX vaccine in HCV infected subjects.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Colesterol/farmacología , Activación de Linfocitos , Fosfolípidos/farmacología , Saponinas/farmacología , Proteínas del Núcleo Viral/inmunología , Adolescente , Adulto , Animales , Colesterol/efectos adversos , Citocinas/metabolismo , Combinación de Medicamentos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Voluntarios Sanos , Anticuerpos contra la Hepatitis C/sangre , Humanos , Inmunización Secundaria/métodos , Masculino , Persona de Mediana Edad , Fosfolípidos/efectos adversos , Placebos/administración & dosificación , Saponinas/efectos adversos , Enfermedades de la Piel/inducido químicamente , Enfermedades de la Piel/patología , Proteínas del Núcleo Viral/efectos adversos , Adulto Joven
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