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1.
medRxiv ; 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39252921

RESUMEN

long: The introduction of artemisinin combination therapies (ACTs) has significantly reduced the burden of Plasmodium falciparum malaria, yet the emergence of artemisinin partial resistance (ART-R) as well as partner drug resistance threatens these gains. Recent confirmations of prevalent de novo ART-R mutations in Africa, in particular in Rwanda, Uganda and Ethiopia, underscore the urgency of addressing this issue in Africa. Our objective is to characterise this evolving resistance landscape in Africa and understand the speed with which ART-R will continue to spread. We produce estimates of both ART-R and partner drug resistance by bringing together WHO, WWARN and MalariaGen Pf7k data on antimalarial resistance in combination with a literature review. We integrate these estimates within a mathematical modelling approach, aincorporating to estimate parameters known to impact the selection of ART-R for each malaria-endemic country and explore scenarios of ART-R spread and establishment. We identify 16 malaria-endemic countries in Africa to prioritise for surveillance and future deployment of alternative antimalarial strategies, based on ART-R reaching greater than 10% prevalence by 2040 under current malaria burden and effective-treatment coverage. If resistance continues to spread at current rates with no change in drug policy, we predict that partner drug resistance will emerge and the mean percentage of treatment failure across Africa will reach 30.74% by 2060 (parameter uncertainty range: 24.98% - 34.54%). This translates to an alarming number of treatment failures, with 52,980,600 absolute cases of treatment failure predicted in 2060 in Africa (parameter uncertainty range: 26,374,200 - 93,672,400) based on current effective treatment coverage. Our results provide a refined and updated prediction model for the emergence of ART-R to help guide antimalarial policy and prioritise future surveillance efforts and innovation in Africa. These results put into stark context the speed with which antimalarial resistance may spread in Africa if left unchecked, confirming the need for swift and decisive action in formulating antimalarial treatment policies focused on furthering malaria control and containing antimalarial resistance in Africa. short: The rise of artemisinin partial resistance (ART-R) and increasing partner drug tolerance by Plasmodium falciparum malaria in Africa threatens to undo malaria control efforts. Recent confirmations of de novo ART-R markers in Rwanda, Uganda, and Ethiopia highlight the urgent need to address this threat in Africa, where the vast majority of cases and deaths occur. This study characterises the resistance landscape and predicts the spread of antimalarial resistance across Africa. We estimate and map the current levels of resistance markers related to artesmisinin and its partner drugs using WHO, WWARN, and MalariaGen Pf7k data. We combine these estimates with current malaria transmission and treatment data and use an established individual-based model of malaria resistance to simulate future resistance spread. We identify 16 African countries at highest risk of ART-R for prioritisation of enhanced surveillance and alternative antimalarial strategies. We project that, without policy changes, ART-R will exceed 10% in these regions by 2040. By 2060, if resistance spreads unchecked, we predict mean treatment failure rates will reach 30.74% (parameter uncertainty range: 24.98% - 34.54%) across Africa. This alarming spread of resistance is predicted to cause 52.98 million treatment failures (uncertainty range: 26.37 million - 93.67 million) in 2060. The impact of antimalarial resistance in Africa, if left unchecked, would hugely damage efforts to reduce malaria burden. Our results underscore the critical need for swift policy action to contain resistance and guide future surveillance and intervention efforts.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39262335

RESUMEN

The underlying pathophysiological mechanisms of exercise-induced laryngeal obstruction (EILO) remain to be fully established. It is hypothesised that high inspiratory flow rates can exert a force on laryngeal airway wall that contributeto its inward collapse causing obstruction. Computational fluid dynamics (CFD) presents an opportunity to explore the distribution of forces in a patient specific upper airway geometry. The current study combined exercise physiological data and CFD simulation to explore differences in airflow and force distribution between an EILO patient and a healthy-matched control. Subjects underwent incremental exercise testing with continuous recording of respiratory airflow and laryngoscopic video, followed by an MRI scan. The respiratory and MRI data were used to generate a subject specific CFD model of upper respiratory airflow. In the EILO patient, the posterior supraglottis experiences an inwardly directed net force, whose magnitude increases nonlinearly with larger flow rates, with slight changes in the direction toward the centre of the airway. The control demonstrated an outwardly directed force at all regions of the wall, with a magnitude that increases linearly with larger flow rates. A comparison is made between the CFD results and endoscopic visualisation of supraglottic collapse, and very good agreement is found. We present the first hybrid physiological / computational approach to investigate the pathophysiological mechanisms of EILO. The method shows great potential and the preliminary findings should be confirmed in larger sample sizes.

3.
bioRxiv ; 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39257734

RESUMEN

Region-specific synapse loss is an early pathological hallmark in Alzheimer's disease (AD). Emerging data in mice and humans highlight microglia, the brain-resident macrophages, as cellular mediators of synapse loss; however, the upstream modulators of microglia-synapse engulfment remain elusive. Here, we report a distinct subset of astrocytes, which are glial cells essential for maintaining synapse homeostasis, appearing in a region-specific manner with age and amyloidosis at onset of synapse loss. These astrocytes are distinguished by their peri-synaptic processes which are 'bulbous' in morphology, contain accumulated p62-immunoreactive bodies, and have reduced territorial domains, resulting in a decrease of astrocyte-synapse coverage. Using integrated in vitro and in vivo approaches, we show that astrocytes upregulate and secrete phagocytic modulator, milk fat globule-EGF factor 8 (MFG-E8), which is sufficient and necessary for promoting microglia-synapse engulfment in their local milieu. Finally, we show that knocking down Mfge8 specifically from astrocytes using a viral CRISPR-saCas9 system prevents microglia-synapse engulfment and ameliorates synapse loss in two independent amyloidosis mouse models of AD. Altogether, our findings highlight astrocyte-microglia crosstalk in determining synapse fate in amyloid models and nominate astrocytic MFGE8 as a potential target to ameliorate synapse loss during the earliest stages of AD.

4.
Anal Bioanal Chem ; 416(22): 4833-4848, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39090266

RESUMEN

The increasing recognition of the health impacts from human exposure to per- and polyfluorinated alkyl substances (PFAS) has surged the need for sophisticated analytical techniques and advanced data analyses, especially for assessing exposure by food of animal origin. Despite the existence of nearly 15,000 PFAS listed in the CompTox chemicals dashboard by the US Environmental Protection Agency, conventional monitoring and suspect screening methods often fall short, covering only a fraction of these substances. This study introduces an innovative automated data processing workflow, named PFlow, for identifying PFAS in environmental samples using direct infusion Fourier transform ion cyclotron resonance mass spectrometry (DI-FT-ICR MS). PFlow's validation on a bream liver sample, representative of low-concentration biota, involves data pre-processing, annotation of PFAS based on their precursor masses, and verification through isotopologues. Notably, PFlow annotated 17 PFAS absent in the comprehensive targeted approach and tentatively identified an additional 53 compounds, thereby demonstrating its efficiency in enhancing PFAS detection coverage. From an initial dataset of 30,332 distinct m/z values, PFlow thoroughly narrowed down the candidates to 84 potential PFAS compounds, utilizing precise mass measurements and chemical logic criteria, underscoring its potential in advancing our understanding of PFAS prevalence and of human exposure.


Asunto(s)
Fluorocarburos , Espectrometría de Masas , Animales , Espectrometría de Masas/métodos , Fluorocarburos/análisis , Flujo de Trabajo , Biota , Automatización , Monitoreo del Ambiente/métodos , Humanos , Hígado/química
5.
J Med Internet Res ; 26: e49655, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39094106

RESUMEN

BACKGROUND: Efforts are underway to capitalize on the computational power of the data collected in electronic medical records (EMRs) to achieve a learning health system (LHS). Artificial intelligence (AI) in health care has promised to improve clinical outcomes, and many researchers are developing AI algorithms on retrospective data sets. Integrating these algorithms with real-time EMR data is rare. There is a poor understanding of the current enablers and barriers to empower this shift from data set-based use to real-time implementation of AI in health systems. Exploring these factors holds promise for uncovering actionable insights toward the successful integration of AI into clinical workflows. OBJECTIVE: The first objective was to conduct a systematic literature review to identify the evidence of enablers and barriers regarding the real-world implementation of AI in hospital settings. The second objective was to map the identified enablers and barriers to a 3-horizon framework to enable the successful digital health transformation of hospitals to achieve an LHS. METHODS: The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were adhered to. PubMed, Scopus, Web of Science, and IEEE Xplore were searched for studies published between January 2010 and January 2022. Articles with case studies and guidelines on the implementation of AI analytics in hospital settings using EMR data were included. We excluded studies conducted in primary and community care settings. Quality assessment of the identified papers was conducted using the Mixed Methods Appraisal Tool and ADAPTE frameworks. We coded evidence from the included studies that related to enablers of and barriers to AI implementation. The findings were mapped to the 3-horizon framework to provide a road map for hospitals to integrate AI analytics. RESULTS: Of the 1247 studies screened, 26 (2.09%) met the inclusion criteria. In total, 65% (17/26) of the studies implemented AI analytics for enhancing the care of hospitalized patients, whereas the remaining 35% (9/26) provided implementation guidelines. Of the final 26 papers, the quality of 21 (81%) was assessed as poor. A total of 28 enablers was identified; 8 (29%) were new in this study. A total of 18 barriers was identified; 5 (28%) were newly found. Most of these newly identified factors were related to information and technology. Actionable recommendations for the implementation of AI toward achieving an LHS were provided by mapping the findings to a 3-horizon framework. CONCLUSIONS: Significant issues exist in implementing AI in health care. Shifting from validating data sets to working with live data is challenging. This review incorporated the identified enablers and barriers into a 3-horizon framework, offering actionable recommendations for implementing AI analytics to achieve an LHS. The findings of this study can assist hospitals in steering their strategic planning toward successful adoption of AI.


Asunto(s)
Inteligencia Artificial , Aprendizaje del Sistema de Salud , Humanos , Registros Electrónicos de Salud , Hospitales
7.
Sci Rep ; 14(1): 17888, 2024 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-39095511

RESUMEN

Globally, catadromous freshwater eels of the genus Anguilla are of conservation concern, including critically endangered European eel (Anguilla anguilla). Pumping stations that move river water to a higher elevation severely impact eels during their seaward spawning migration. Fish-friendly pumps can mitigate fish injury and mortality but here we uniquely rethink a fish-friendly pump as a fish passage solution. In this pluriannual study, the seasonal timing of pump operation was misaligned with the typical silver eel migration period. Eels were almost exclusively nocturnal but night-time pumping represented as little as 5.6% a year. Night-time eel approaches were primarily influenced by pump duration and temperature, but did not align with lunar phase, unlike in unregulated rivers. After reaching the pumping station, eel passage was influenced by weedscreen aperture and increased when the aperture was increased. Passive sensor collision suggested non-pump infrastructure could cause injury and mortality to eels. It is therefore recommended pump operation should align with the timing of silver eel migration, weedscreen and pump entrance efficiencies should be maximised, and non-pump infrastructure must have low fish injury risk. Ultimately, considering the entire structure a fish passage solution will help ensure fish-friendly pumps have high conservation value for anguillid eels globally.


Asunto(s)
Anguilla , Migración Animal , Conservación de los Recursos Naturales , Animales , Migración Animal/fisiología , Anguilla/fisiología , Conservación de los Recursos Naturales/métodos , Ríos , Estaciones del Año , Especies en Peligro de Extinción
8.
Nat Commun ; 15(1): 6518, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39117623

RESUMEN

Amyotrophic lateral sclerosis (ALS) is characterized by degeneration of motor neurons in the central nervous system (CNS). Mutations in the metalloenzyme SOD1 are associated with inherited forms of ALS and cause a toxic gain of function thought to be mediated by dimer destabilization and misfolding. SOD1 binds two Cu and two Zn ions in its homodimeric form. We have applied native ambient mass spectrometry imaging to visualize the spatial distributions of intact metal-bound SOD1G93A complexes in SOD1G93A transgenic mouse spinal cord and brain sections and evaluated them against disease pathology. The molecular specificity of our approach reveals that metal-deficient SOD1G93A species are abundant in CNS structures correlating with ALS pathology whereas fully metalated SOD1G93A species are homogenously distributed. Monomer abundance did not correlate with pathology. We also show that the dimer-destabilizing post-translational modification, glutathionylation, has limited influence on the spatial distribution of SOD1 dimers.


Asunto(s)
Esclerosis Amiotrófica Lateral , Encéfalo , Espectrometría de Masas , Ratones Transgénicos , Médula Espinal , Superóxido Dismutasa-1 , Animales , Superóxido Dismutasa-1/genética , Superóxido Dismutasa-1/metabolismo , Superóxido Dismutasa-1/química , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Ratones , Médula Espinal/metabolismo , Médula Espinal/patología , Espectrometría de Masas/métodos , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Cobre/metabolismo , Zinc/metabolismo , Humanos , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/genética , Superóxido Dismutasa/química , Mutación , Procesamiento Proteico-Postraduccional , Multimerización de Proteína , Modelos Animales de Enfermedad , Masculino
9.
Mil Med ; 189(Supplement_3): 254-261, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160838

RESUMEN

INTRODUCTION: The initial management of penetrating ocular injuries is a major sight-threatening problem for both civilian and military medicine. A novel device (Eye-Aid) temporarily tamponades leakage from such injuries while being easy to remove upon arrival to specialized ophthalmologic care. Eye-Aid consists of a protective eye shield with an adhesive backing that connects to a portable canister containing rapidly deployable thermoresponsive foam. The aim of this study was to compare the use of the novel Eye-Aid device to control in a new live swine ocular injury model. MATERIALS AND METHODS: Bilateral penetrating ocular injuries were created on 14 male Yorkshire swine in a standardized manner using a 16-gauge needle device to puncture the central cornea and cause a full-thickness wound. Researchers randomized eye intervention side, with the contralateral eye used as paired control. Two minutes after the injury, the eye shield components of the Eye-Aid system, which has a sticky pad for attachment to the skin and a luer-lock for foam deployment, were placed bilaterally. Eight minutes after the injury, foam was deployed for the intervention eye according to the device instructions for use. For the control eye, no additional procedures were performed. Six hours post-injury, end A-scan and intraocular pressure (IOP) were measured. Primary study outcome was change in axial length of the globe. Secondary outcomes were as follows: (1) Presence of full anterior chamber collapse, defined as a lack of measurable anterior lens capsule-reflex (ALC-reflex) on A-scan and (2) change in IOP. Outcomes were analyzed as paired intra-animal data, with intervention and control data for each animal. A paired t-test was used to analyze the difference in axial length change and IOP change between treatment groups, whereas a conditional logistic regression was used to analyze dichotomous ALC-reflex outcome and estimate the odds ratio associated with the Eye-Aid device. RESULTS: A significant difference (P < .0001) in mean change in axial length between intervention (-210 µm) and control (-1,202 µm) groups was found. There was a significant difference in ALC-reflex presence, with 79% of eyes having an ALC-reflex in the intervention group, compared to 14% in the control (P = .008). IOP remained higher in the intervention group, with a mean change of -1.5 mmHg for the intervention group compared to -4.0 mmHg in the control (P = .0001). CONCLUSIONS: This study describes the first development of an in vivo large animal ocular injury model that realistically approximates the emergent time course and pathophysiology of patients with full-thickness corneal open globe injuries. It also gives the first description of using thermoreversible hydrogel foam for such injuries. Eye-Aid was found to be significantly better than control for treatment of such injuries, based on measurements of both structure and pressure. Assuming that the absence of an ALC-reflex demonstrates complete anterior chamber collapse, the Eye-Aid group demonstrated a 79% eye "save" rate compared to only 14% in the control group, as described earlier. This results in a Number Needed to Treat of 3 for this finding. Eye-Aid additionally demonstrated several characteristics that would be beneficial in a device targeted for emergent deployment by non-ophthalmologists.


Asunto(s)
Modelos Animales de Enfermedad , Lesiones Oculares Penetrantes , Animales , Porcinos , Lesiones Oculares Penetrantes/terapia , Masculino , Presión Intraocular/fisiología
10.
Eur J Cancer ; 210: 114258, 2024 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-39168001

RESUMEN

BACKGROUND: Food biodiversity in human diets has potential co-benefits for both public health and sustainable food systems. However, current evidence on the potential relationship between food biodiversity and cancer risk, and particularly gastrointestinal cancers typically related to diet, remains limited. This study evaluated how dietary species richness (DSR) was associated with gastrointestinal cancer risk in a pan-European population. METHODS: Associations between DSR and subsequent gastrointestinal cancer risk were examined among 450,111 adults enrolled in the European Prospective Investigation into Cancer and Nutrition cohort (EPIC, initiated in 1992), free of cancer at baseline. Usual dietary intakes were assessed at recruitment with country-specific dietary questionnaires. DSR of an individual's yearly diet was calculated based on the absolute number of unique biological species in each food and drink item. Associations between DSR and cancer risk were assessed by multivariable Cox proportional hazards regression models. FINDINGS: During a median follow-up time of 14.1 years (SD=3.9), 10,705 participants were diagnosed with gastrointestinal cancer. Hazard ratios (HRs) and 95 % confidence intervals (CIs) comparing overall gastrointestinal cancer risk in the highest versus lowest quintiles of DSR indicated inverse associations in multivariable-adjusted models [HR (95 % CI): 0.77 (0.69-0.87); P-value < 0·0001] (Table 2). Specifically, inverse associations were observed between DSR and oesophageal squamous cell carcinoma, proximal colon, colorectal, and liver cancer risk (p-trend<0.05 for all cancer types). INTERPRETATION: Greater food biodiversity in the diet may lower the risk of certain gastrointestinal cancers. Further research is needed to replicate these novel findings and to understand potential mechanisms.

11.
Commun Psychol ; 2: 80, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39184223

RESUMEN

Anxiety involves the anticipation of aversive outcomes and can impair neurocognitive processes, such as the ability to recall faces encoded during the anxious state. It is important to precisely delineate and determine the replicability of these effects using causal state anxiety inductions in the general population. This study therefore aimed to replicate prior research on the distinct impacts of threat-of-shock-induced anxiety on the encoding and recognition stage of emotional face processing, in a large asymptomatic sample (n = 92). We successfully replicated previous results demonstrating impaired recognition of faces encoded under threat-of-shock. This was supported by a mega-analysis across three independent studies using the same paradigm (n = 211). Underlying this, a whole-brain fMRI analysis revealed enhanced activation in the posterior cingulate cortex (PCC), alongside previously seen activity in the anterior cingulate cortex (ACC) when combined in a mega-analysis with the fMRI findings we aimed to replicate. We further found replications of hippocampus activation when the retrieval and encoding states were congruent. Our results support the notion that state anxiety disrupts face recognition, potentially due to attentional demands of anxious arousal competing with affective stimuli processing during encoding and suggest that regions of the cingulate cortex play pivotal roles in this.

13.
J Physiol ; 602(17): 4157-4170, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39097829

RESUMEN

The effect of acute exercise on circulating concentrations of vitamin D metabolites is unclear. To address this knowledge gap, we examined the effect of a bout of treadmill-based exercise versus rest on circulating concentrations of 25(OH)D3, 25(OH)D2, 3-epi-25(OH)D3, 24,25(OH)2D3, 1,25(OH)2D3, and vitamin D2 and D3 in healthy men and women. Thirty-three healthy adults (14 females, 41 (15) years, body mass index 26.2 (3.7) kg/m2, V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ 36.2 (9.2) ml/kg/min; mean (SD)) completed two laboratory visits involving 60 min of moderate-intensity treadmill exercise (60% V ̇ O 2 max ${{\dot{V}}_{{{{\mathrm{O}}}_{\mathrm{2}}}{\mathrm{max}}}}$ ) versus 60 min of seated rest, both in an overnight fasted-state, as part of a randomised crossover design. Venous blood samples were drawn at baseline, immediately (0 h), 1 h and 24 h after the exercise or rest-period. There was a significant time × trial interaction effect for total circulating 25(OH)D (P = 0.0148), 25(OH)D3 (P = 0.0127) and 1,25(OH)2D3 (P = 0.0226). Immediately post-exercise, 25(OH)D, 25(OH)D3 and 1,25(OH)2D3 concentrations were significantly elevated compared to the control resting condition, and 1,25(OH) 2D3 remained significantly elevated 1 h later. Circulating albumin, vitamin D binding protein, calcium and parathyroid hormone were elevated immediately post-exercise. Thus, an acute bout of moderate intensity exercise transiently increases concentrations of circulating 25(OH)D and 1,25(OH)2D3 compared to resting conditions. KEY POINTS: Observational studies suggest that acute exercise might change circulating concentrations of vitamin D metabolites, but this has not been investigated using randomised crossover studies and using robust analytical procedures. In this study, we used a randomised crossover design to examine the effect of a bout of treadmill-based exercise (vs. rest) on circulating concentrations of a wide range of vitamin D metabolites in healthy humans. We show that an acute bout of moderate intensity exercise transiently increases concentrations of circulating 25(OH)D and 1,25(OH)2D3 compared to resting conditions. These findings indicate that regular exercise could lead to transient but regular windows of enhanced vitamin D biological action.


Asunto(s)
Estudios Cruzados , Ejercicio Físico , Vitamina D , Humanos , Masculino , Adulto , Femenino , Ejercicio Físico/fisiología , Vitamina D/sangre , Vitamina D/análogos & derivados , Persona de Mediana Edad , Adulto Joven
14.
J Interpers Violence ; : 8862605241271349, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39169727

RESUMEN

While sexual harm has been studied across a range of contexts, it has not yet been considered within the video game, streaming, and esports community. This study aimed to explore the landscape of sexual harm in this community, specifically, where it has been committed by esports professionals and video game live streamers. Fifty-five victim statements were extracted from online sources (such as Twitter/X and Reddit) and coded into variables relating to offender and victim demographics, offense characteristics, the offense process, and platform(s) used. Descriptive statistics were generated for each variable and Fisher's exact tests were conducted to examine the differences between adult-on-adult and adult-on-child cases. The findings reveal diverse offense outcomes across the sample, ranging from rape to sexual communication with a child. Some offense patterns can be seen in wider sexual offending literature, such as pre-offense alcohol consumption, offending against incapacitated victims (e.g., sleeping), and offending within an established romantic relationship. However, several offense process characteristics unique to the video gaming community were identified. These included offenders using their position of fame within the community to access victims and bypass the need for other coercive behaviors. Online offenses were more common with children and offenders demonstrated a preference for "live" methods, such as voice chat and video calling, rather than instant messaging or sharing images of themselves. This limits the digital evidence left behind and indicates the offenders' greater technological literacy. The study's findings shed light on the sexual harm that exists within this previously unexplored context and highlight areas where esports organizations, live-streaming platforms, and educational providers can do more to safeguard players, fans, and viewers in this community.

15.
Nature ; 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39169180

RESUMEN

For over a century, fasting regimens have improved health, lifespan and tissue regeneration in diverse organisms, including humans1-6. However, how fasting and post-fast refeeding affect adult stem cells and tumour formation has yet to be explored in depth. Here we demonstrate that post-fast refeeding increases intestinal stem cell (ISC) proliferation and tumour formation; post-fast refeeding augments the regenerative capacity of Lgr5+ ISCs, and loss of the tumour suppressor gene Apc in post-fast-refed ISCs leads to a higher tumour incidence in the small intestine and colon than in the fasted or ad libitum-fed states, demonstrating that post-fast refeeding is a distinct state. Mechanistically, we discovered that robust mTORC1 induction in post-fast-refed ISCs increases protein synthesis via polyamine metabolism to drive these changes, as inhibition of mTORC1, polyamine metabolite production or protein synthesis abrogates the regenerative or tumorigenic effects of post-fast refeeding. Given our findings, fast-refeeding cycles must be carefully considered and tested when planning diet-based strategies for regeneration without increasing cancer risk, as post-fast refeeding leads to a burst in stem-cell-driven regeneration and tumorigenicity.

17.
J Appl Clin Med Phys ; : e14455, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39101683

RESUMEN

BACKGROUND: Failure mode and effects analysis (FMEA) is a valuable tool for radiotherapy risk assessment, yet its outputs might be unreliable due to failures not being identified or due to a lack of accurate error rates. PURPOSE: A novel incident reporting system (IRS) linked to an FMEA database was tested and evaluated. The study investigated whether the system was suitable for validating a previously performed analysis and whether it could provide accurate error rates to support the expert occurrence ratings of previously identified failure modes. METHODS: Twenty-three pre-identified failure modes of our external beam radiotherapy process, covering the process steps from patient admission to treatment delivery, were proffered on dedicated FMEA feedback and incident reporting terminals generated by the IRS. The clinical setting involved a computed tomography scanner, dosimetry, and five linacs. Incoming reports were used as basis to identify additional failure modes or confirm initial ones. The Kruskal-Wallis H test was applied to compare the risk priorities of the retrospective and prospective failure modes. Wald's sequential probability ratio test was used to investigate the correctness of the experts' occurrence ratings by means of the number of incoming reports. RESULTS: Over a 15-month period, 304 reports were submitted. There were 0.005 (confidence interval [CI], 0.0014-0.0082) reported incidents per imaging study and 0.0006 (CI, 0.0003-0.0009) reported incidents per treatment fraction. Sixteen additional failure modes could be identified, and their risk priorities did not differ from those of the initial failure modes (p = 0.954). One failure mode occurrence rating could be increased, whereas the other 22 occurrence ratings could not be disproved. CONCLUSIONS: Our approach is suitable for validating FMEAs and deducing additional failure modes on a continual basis. Accurate error rates can only be provided if a sufficient number of reports is available.

18.
Behav Brain Res ; 474: 115192, 2024 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-39127128

RESUMEN

Generalized anxiety disorder is characterized by disruptions in decision-making, including an enhanced aversion to uncertain outcomes (i.e., risk aversion), which is not specific to negative outcomes (i.e., no loss aversion). It is unknown if this uncertainty bias is a trait-like causal factor contributing to anxiety symptoms, or a state-like feature triggered by anxiety symptoms such as worry chains. Here, in-patients with Major Depression Disorder (MDD), with (N = 16) or without (N = 24) Generalized anxiety (GA) symptoms, and healthy controls (N = 23), completed an economic decision-making task before and after worry induction. They were asked to choose between a certain monetary payoff, and an uncertain gamble, allowing for estimation of risk and loss aversion through a computational prospect-theoretic model. There were no significant differences in risk and loss aversion between any of the three groups at baseline. After worry induction, patients with GA symptoms, compared to those without, showed increased risk aversion. This increase was modulated by the severity of anxiety symptoms. These findings suggest that decision-making disruptions in anxiety disorder may be driven by anxiety symptoms such as worry, rather than causing them. This could shape etiological models, motivate standardization of emotional state in research on decision-making in anxiety disorders, support treatment strategies primarily aimed at worry management, and could guide novel interventions focusing on uncertainty exposure across aversive and appetitive domains.


Asunto(s)
Trastornos de Ansiedad , Ansiedad , Toma de Decisiones , Trastorno Depresivo Mayor , Humanos , Masculino , Femenino , Adulto , Toma de Decisiones/fisiología , Incertidumbre , Trastorno Depresivo Mayor/psicología , Asunción de Riesgos , Persona de Mediana Edad , Adulto Joven
19.
J Alzheimers Dis ; 101(1): 111-131, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39121131

RESUMEN

Background: While Alzheimer's disease (AD) has been extensively studied with a focus on cognitive networks, visual network dysfunction has received less attention despite compelling evidence of its significance in AD patients and mouse models. We recently reported c-Fos and synaptic dysregulation in the primary visual cortex of a pre-amyloid plaque AD-model. Objective: We test whether c-Fos expression and presynaptic density/dynamics differ in cortical and subcortical visual areas in an AD-model. We also examine whether aberrant c-Fos expression is inherited through functional connectivity and shaped by light experience. Methods: c-Fos+ cell density, functional connectivity, and their experience-dependent modulation were assessed for visual and whole-brain networks in both sexes of 4-6-month-old J20 (AD-model) and wildtype (WT) mice. Cortical and subcortical differences in presynaptic vulnerability in the AD-model were compared using ex vivo and in vivo imaging. Results: Visual cortical, but not subcortical, networks show aberrant c-Fos expression and impaired experience-dependent modulation. The average functional connectivity of a brain region in WT mice significantly predicts aberrant c-Fos expression, which correlates with impaired experience-dependent modulation in the AD-model. We observed a subtle yet selective weakening of excitatory visual cortical synapses. The size distribution of cortical boutons in the AD-model is downscaled relative to those in WT mice, suggesting a synaptic scaling-like adaptation of bouton size. Conclusions: Visual network structural and functional disruptions are biased toward cortical regions in pre-plaque J20 mice, and the cellular and synaptic dysregulation in the AD-model represents a maladaptive modification of the baseline physiology seen in WT conditions.


Asunto(s)
Enfermedad de Alzheimer , Modelos Animales de Enfermedad , Ratones Transgénicos , Proteínas Proto-Oncogénicas c-fos , Sinapsis , Animales , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/genética , Sinapsis/patología , Sinapsis/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratones , Masculino , Femenino , Corteza Visual/metabolismo , Corteza Visual/patología , Ratones Endogámicos C57BL
20.
Physiol Rep ; 12(16): e70006, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39175108

RESUMEN

Environmental air pollution presents a considerable risk to global respiratory health. If critical levels are exceeded, inhaled pollutants can lead to the development of respiratory dysfunction and provoke exacerbation in those with pre-existing chronic respiratory disease. Over 90% of the global population currently reside in areas where environmental air pollution is considered excessive-with adverse effects ranging from acute airway irritation to complex immunomodulatory alterations. This narrative review provides an up-to-date perspective concerning the impact of environmental air pollution on respiratory health and function and describes the underpinning mechanisms that contribute to the development and progression of chronic respiratory disease.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Contaminación del Aire/efectos adversos , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/toxicidad , Enfermedades Respiratorias/etiología , Enfermedades Respiratorias/inducido químicamente , Enfermedades Respiratorias/fisiopatología , Animales , Exposición a Riesgos Ambientales/efectos adversos
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