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1.
Circulation ; 148(21): 1680-1690, 2023 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-37746692

RESUMEN

BACKGROUND: Anthracycline-induced cardiotoxicity has a variable incidence, and the development of left ventricular dysfunction is preceded by elevations in cardiac troponin concentrations. Beta-adrenergic receptor blocker and renin-angiotensin system inhibitor therapies have been associated with modest cardioprotective effects in unselected patients receiving anthracycline chemotherapy. METHODS: In a multicenter, prospective, randomized, open-label, blinded end-point trial, patients with breast cancer and non-Hodgkin lymphoma receiving anthracycline chemotherapy underwent serial high-sensitivity cardiac troponin testing and cardiac magnetic resonance imaging before and 6 months after anthracycline treatment. Patients at high risk of cardiotoxicity (cardiac troponin I concentrations in the upper tertile during chemotherapy) were randomized to standard care plus cardioprotection (combination carvedilol and candesartan therapy) or standard care alone. The primary outcome was adjusted change in left ventricular ejection fraction at 6 months. In low-risk nonrandomized patients with cardiac troponin I concentrations in the lower 2 tertiles, we hypothesized the absence of a 6-month change in left ventricular ejection fraction and tested for equivalence of ±2%. RESULTS: Between October 2017 and June 2021, 175 patients (mean age, 53 years; 87% female; 71% with breast cancer) were recruited. Patients randomized to cardioprotection (n=29) or standard care (n=28) had left ventricular ejection fractions of 69.4±7.4% and 69.1±6.1% at baseline and 65.7±6.6% and 64.9±5.9% 6 months after completion of chemotherapy, respectively. After adjustment for age, pretreatment left ventricular ejection fraction, and planned anthracycline dose, the estimated mean difference in 6-month left ventricular ejection fraction between the cardioprotection and standard care groups was -0.37% (95% CI, -3.59% to 2.85%; P=0.82). In low-risk nonrandomized patients, baseline and 6-month left ventricular ejection fractions were 69.3±5.7% and 66.4±6.3%, respectively: estimated mean difference, 2.87% (95% CI, 1.63%-4.10%; P=0.92, not equivalent). CONCLUSIONS: Combination candesartan and carvedilol therapy had no demonstrable cardioprotective effect in patients receiving anthracycline-based chemotherapy with high-risk on-treatment cardiac troponin I concentrations. Low-risk nonrandomized patients had similar declines in left ventricular ejection fraction, bringing into question the utility of routine cardiac troponin monitoring. Furthermore, the modest declines in left ventricular ejection fraction suggest that the value and clinical impact of early cardioprotection therapy need to be better defined in patients receiving high-dose anthracycline. REGISTRATION: URL: https://doi.org; Unique identifier: 10.1186/ISRCTN24439460. URL: https://www.clinicaltrialsregister.eu/ctr-search/search; Unique identifier: 2017-000896-99.


Asunto(s)
Antraciclinas , Neoplasias de la Mama , Humanos , Femenino , Persona de Mediana Edad , Masculino , Antraciclinas/efectos adversos , Troponina I , Volumen Sistólico , Carvedilol/uso terapéutico , Cardiotoxicidad/etiología , Función Ventricular Izquierda , Estudios Prospectivos , Antibióticos Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Antagonistas Adrenérgicos beta/uso terapéutico , Antagonistas Adrenérgicos beta/farmacología
2.
J Gen Intern Med ; 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39020226

RESUMEN

BACKGROUND: The COVID-19 pandemic disproportionately affected people from structurally vulnerable communities. There was a need to improve COVID-19 testing in these communities to reduce viral spread and connect to treatment. OBJECTIVE: We created a partnership between an academic medical center and three community-based organizations (CBOs) to offer low-barrier COVID-19 walk-up testing clinics in Portland, Maine. Our objective was to examine whether the co-created testing clinics reached structurally vulnerable populations. DESIGN: The clinics offered COVID-19 rapid antigen tests three times a week outside CBO sites from January 2022 to May 2023. Clinic staff administered a brief survey on reason for testing and then instructed participants on how to self-swab. While staff processed the test, participants were invited to complete an additional survey about their demographics and testing perceptions. PARTICIPANTS: Adults seeking COVID-19 testing with specific outreach to people who are unhoused, immigrants, and low-income and/or uninsured. MAIN MEASURES: Number of tests conducted and result, reasons for testing, and testing perceptions. KEY RESULTS: Of 246 completed tests, 18 were positive for COVID-19 (7%). Participants sought testing for a variety of reasons, including symptoms (60%), close contact exposure (29%), and/or need for a negative test result to access services or an activity (33%). Overall, people primarily tested due to symptoms with only 7% testing due to close contact exposure alone. The clinics reached vulnerable populations. Among the 130 people completing the participant survey, 39% were unhoused, 22% spoke a language other than English at home, 23% were uninsured, and 46% earned less than $20,000 in 2019. Qualitative field notes captured key elements of clinics that influenced reach, and how this collaboration with CBOs helped build trust with our target populations. CONCLUSIONS: Providing low-barrier walk-up clinics partnering with trusted CBOs was observed to be helpful in reaching structurally vulnerable populations for COVID-19 testing.

3.
J Cardiovasc Magn Reson ; 26(2): 101074, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39096971

RESUMEN

BACKGROUND: Dysregulated myocardial calcium handling has been demonstrated in ischemic, non-ischemic and diabetic cardiomyopathy. Manganese-enhanced MRI (MEMRI) provides a unique method to quantify in-vivo myocardial calcium uptake but no studies have so far utilized MEMRI in patients with aortic stenosis (AS). We sought to: 1) determine whether myocardial calcium uptake is perturbed in people with severe AS, and 2) assess change in calcium uptake following aortic valve replacement (AVR). METHODS: In this prospective, pilot, case-control study, adults with severe AS underwent MEMRI before and after AVR. A group of healthy controls were also recruited. The primary outcome was the rate of manganese uptake (Ki) as assessed by Patlak modeling to act as a surrogate of myocardial calcium uptake. Comparison of Ki between groups was adjusted for age, body mass index (BMI) and systolic blood pressure. RESULTS: Twenty-eight controls and ten subjects with severe AS (age 72 [61-75] years, 8 male, 7 symptomatic, valve area 0.81 [0.74-1.0] cm2) were recruited, with seven returning for repeat scans post-AVR. AS patients had higher BMI and blood pressure, and a greater incidence of hyperlipidemia compared to controls. Baseline left ventricular (LV) volumes were similar between the groups, but the AS patients had higher indexed left ventricular mass. Global longitudinal strain and peak early diastolic strain rate were lower in the AS group. There was no significant difference in Ki between patients with severe AS and controls (7.09 [6.33-8.99] vs. 8.15 [7.54-8.78] mL/100g of tissue/min, P=0.815). Following AVR, there was regression in indexed LV mass (68 [51-79] to 49 [47-65] g/m2, P=0.018) and mass-volume ratio (0.94 [0.80-1.13] to 0.74 [0.71-0.82] g/mL, P=0.028) but no change in Ki was seen (7.35 [6.81-8.96] to 7.11 [6.16-8.01] mL/100 g of tissue/min, P=0.499). CONCLUSIONS: Despite clear features of adverse LV remodeling and systolic dysfunction, patients with severe AS demonstrated no alteration in calcium uptake at baseline compared to controls. Moreover, AVR led to reverse LV remodeling but no notable change in calcium uptake was seen. This may suggest that altered myocardial calcium handling does not play a significant pathophysiological role in AS.

4.
Circulation ; 146(24): 1823-1835, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36317524

RESUMEN

BACKGROUND: Takotsubo syndrome is an acute cardiac emergency characterized by transient left ventricular systolic dysfunction typically following a stressful event. Despite its rapidly rising incidence, its pathophysiology remains poorly understood. Takotsubo syndrome may pass unrecognized, especially if timely diagnostic imaging is not performed. Defective myocardial calcium homeostasis is a central cause of contractile dysfunction and has not been explored in takotsubo syndrome. We aimed to investigate myocardial calcium handling using manganese-enhanced magnetic resonance imaging during the acute and recovery phases of takotsubo syndrome. METHODS: Twenty patients with takotsubo syndrome (63±12 years of age; 90% female) and 20 volunteers matched on age, sex, and cardiovascular risk factors (59±11 years of age; 70% female) were recruited from the Edinburgh Heart Centre between March 2020 and October 2021. Patients underwent gadolinium and manganese-enhanced magnetic resonance imaging during index hospitalization with repeat manganese-enhanced magnetic resonance imaging performed after at least 3 months. RESULTS: Compared with matched control volunteers, patients had a reduced left ventricular ejection fraction (51±11 versus 67±8%; P<0.001), increased left ventricular mass (86±11 versus 57±14 g/m2; P<0.001), and, in affected myocardial segments, elevated native T1 (1358±49 versus 1211±28 ms; P<0.001) and T2 (60±7 versus 38±3 ms; P<0.0001) values at their index presentation. During manganese-enhanced imaging, kinetic modeling demonstrated a substantial reduction in myocardial manganese uptake (5.1±0.5 versus 8.2±1.1 mL/[100 g of tissue ·min], respectively; P<0.0001), consistent with markedly abnormal myocardial calcium handling. After recovery, left ejection fraction, left ventricular mass, and T2 values were comparable with those of matched control volunteers. Despite this, native and postmanganese T1 and myocardial manganese uptake remained abnormal compared with matched control volunteers (6.6±0.5 versus 8.2±1.1 mL/[100 g of tissue ·min]; P<0.0001). CONCLUSIONS: In patients with takotsubo syndrome, there is a profound perturbation of myocardial manganese uptake, which is most marked in the acute phase but persists for at least 3 months despite apparent restoration of normal left ventricular ejection fraction and resolution of myocardial edema, suggesting abnormal myocardial calcium handling may be implicated in the pathophysiology of takotsubo syndrome. Manganese-enhanced magnetic resonance imaging has major potential to assist in the diagnosis, characterization, and risk stratification of patients with takotsubo syndrome. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04623788.


Asunto(s)
Cardiomiopatía de Takotsubo , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , Cardiomiopatía de Takotsubo/diagnóstico por imagen , Volumen Sistólico , Función Ventricular Izquierda/fisiología , Manganeso , Calcio , Imagen por Resonancia Magnética , Imagen por Resonancia Cinemagnética/métodos
5.
J Magn Reson Imaging ; 57(4): 1011-1028, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36314991

RESUMEN

Manganese-based contrast media were the first in vivo paramagnetic agents to be used in magnetic resonance imaging (MRI). The uniqueness of manganese lies in its biological function as a calcium channel analog, thus behaving as an intracellular contrast agent. Manganese ions are taken up by voltage-gated calcium channels in viable tissues, such as the liver, pancreas, kidneys, and heart, in response to active calcium-dependent cellular processes. Manganese-enhanced magnetic resonance imaging (MEMRI) has therefore been used as a surrogate marker for cellular calcium handling and interest in its potential clinical applications has recently re-emerged, especially in relation to assessing cellular viability and myocardial function. Calcium homeostasis is central to myocardial contraction and dysfunction of myocardial calcium handling is present in various cardiac pathologies. Recent studies have demonstrated that MEMRI can detect the presence of abnormal myocardial calcium handling in patients with myocardial infarction, providing clear demarcation between the infarcted and viable myocardium. Furthermore, it can provide more subtle assessments of abnormal myocardial calcium handling in patients with cardiomyopathies and being excluded from areas of nonviable cardiomyocytes and severe fibrosis. As such, MEMRI offers exciting potential to improve cardiac diagnoses and provide a noninvasive measure of myocardial function and contractility. This could be an invaluable tool for the assessment of both ischemic and nonischemic cardiomyopathies as well as providing a measure of functional myocardial recovery, an accurate prediction of disease progression and a method of monitoring treatment response. EVIDENCE LEVEL: 5: TECHNICAL EFFICACY: STAGE 5.


Asunto(s)
Cardiomiopatías , Manganeso , Humanos , Calcio , Imagen por Resonancia Magnética/métodos , Medios de Contraste , Miocitos Cardíacos
6.
Diabet Med ; 40(10): e15111, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37035965

RESUMEN

AIMS: To investigate whether manganese-enhanced magnetic resonance imaging can assess functional pancreatic beta-cell mass in people with type 1 diabetes mellitus. METHODS: In a prospective case-control study, 20 people with type 1 diabetes mellitus (10 with low (≥50 pmol/L) and 10 with very low (<50 pmol/L) C-peptide concentrations) and 15 healthy volunteers underwent manganese-enhanced magnetic resonance imaging of the pancreas following an oral glucose load. Scan-rescan reproducibility was performed in 10 participants. RESULTS: Mean pancreatic manganese uptake was 31 ± 6 mL/100 g of tissue/min in healthy volunteers (median 32 [interquartile range 23-36] years, 6 women), falling to 23 ± 4 and 13 ± 5 mL/100 g of tissue/min (p ≤ 0.002 for both) in people with type1 diabetes mellitus (52 [44-61] years, 6 women) and low or very low plasma C-peptide concentrations respectively. Pancreatic manganese uptake correlated strongly with plasma C-peptide concentrations in people with type1 diabetes mellitus (r = 0.73, p < 0.001) but not in healthy volunteers (r = -0.054, p = 0.880). There were no statistically significant correlations between manganese uptake and age, body-mass index, or glycated haemoglobin. There was strong intra-observer (mean difference: 0.31 (limits of agreement -1.42 to 2.05) mL/100 g of tissue/min; intra-class correlation, ICC = 0.99), inter-observer (-1.23 (-5.74 to 3.27) mL/100 g of tissue/min; ICC = 0.85) and scan-rescan (-0.72 (-2.9 to 1.6) mL/100 g of tissue/min; ICC = 0.96) agreement for pancreatic manganese uptake. CONCLUSIONS: Manganese-enhanced magnetic resonance imaging provides a potential reproducible non-invasive measure of functional beta-cell mass in people with type 1 diabetes mellitus. This holds major promise for investigating type 1 diabetes, monitoring disease progression and assessing novel immunomodulatory interventions.


Asunto(s)
Diabetes Mellitus Tipo 1 , Células Secretoras de Insulina , Humanos , Femenino , Péptido C , Manganeso , Reproducibilidad de los Resultados , Estudios de Casos y Controles , Células Secretoras de Insulina/patología
7.
Proc Natl Acad Sci U S A ; 112(26): E3374-83, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-26080397

RESUMEN

Pre-mRNA splicing is a complex regulatory nexus modulated by various trans-factors and their posttranslational modifications to create a dynamic transcriptome through alternative splicing. Signal-induced phosphorylation and dephosphorylation of trans-factors are known to regulate alternative splicing. However, the role of other posttranslational modifications, such as deacetylation/acetylation, methylation, and ubiquitination, that could modulate alternative splicing in either a signal-dependent or -independent manner remain enigmatic. Here, we demonstrate that Scaffold/matrix-associated region-binding protein 1 (SMAR1) negatively regulates alternative splicing through histone deacetylase 6 (HDAC6)-mediated deacetylation of RNA-binding protein Sam68 (Src-associated substrate during mitosis of 68 kDa). SMAR1 is enriched in nuclear splicing speckles and associates with the snRNAs that are involved in splice site recognition. ERK-MAPK pathway that regulates alternative splicing facilitates ERK-1/2-mediated phosphorylation of SMAR1 at threonines 345 and 360 and localizes SMAR1 to the cytoplasm, preventing its interaction with Sam68. We showed that endogenously, SMAR1 through HDAC6 maintains Sam68 in a deacetylated state. However, knockdown or ERK-mediated phosphorylation of SMAR1 releases the inhibitory SMAR1-HDAC6-Sam68 complex, facilitating Sam68 acetylation and alternative splicing. Furthermore, loss of heterozygosity at the Chr.16q24.3 locus in breast cancer cells, wherein the human homolog of SMAR1 (BANP) has been mapped, enhances Sam68 acetylation and CD44 variant exon inclusion. In addition, tail-vein injections in mice with human breast cancer MCF-7 cells depleted for SMAR1 showed increased CD44 variant exon inclusion and concomitant metastatic propensity, confirming the functional role of SMAR1 in regulation of alternative splicing. Thus, our results reveal the complex molecular mechanism underlying SMAR1-mediated signal-dependent and -independent regulation of alternative splicing via Sam68 deacetylation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Empalme Alternativo/fisiología , Proteínas de Ciclo Celular/fisiología , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/fisiología , Histona Desacetilasas/metabolismo , Matriz Nuclear/metabolismo , Proteínas Nucleares/fisiología , Proteínas de Unión al ARN/metabolismo , Acetilación , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Citoplasma/metabolismo , Proteínas de Unión al ADN/genética , Técnicas de Silenciamiento del Gen , Histona Desacetilasa 6 , Humanos , Receptores de Hialuranos/genética , Sistema de Señalización de MAP Quinasas , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Transporte de Proteínas
8.
Pediatr Phys Ther ; 28(4): 490-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27661250

RESUMEN

PURPOSE: Juvenile idiopathic arthritis (JIA) is a cause of disability in childhood. Little research exists concerning physical therapy management, and no evidence exists for orthopedic manual physical therapy (OMPT) for JIA. The purpose of this case report is to describe the use of OMPT in combination with therapeutic exercise in the successful treatment of a child with oligoarticular JIA. KEY POINTS: A 6-year-old girl with oligoarticular JIA presented with elbow pain and stiffness interfering with function. Treatment consisted of OMPT in combination with therapeutic exercise and a home exercise program. CONCLUSIONS: Improvements were demonstrated in elbow range of motion, pain, Childhood Health Assessment Questionnaire, Pediatric Outcomes Data Collection Instrument, and the Patient Specific Functional Scale. RECOMMENDATIONS FOR CLINICAL PRACTICE: Orthopedic manual physical therapy may be considered as a treatment of a child with JIA. RECOMMENDATIONS: We provide evidence that OMPT may be considered as a treatment of a child with JIA.


Asunto(s)
Artralgia/rehabilitación , Artritis Juvenil/rehabilitación , Codo , Terapia por Ejercicio/métodos , Manipulaciones Musculoesqueléticas/métodos , Artritis Juvenil/fisiopatología , Niño , Evaluación de la Discapacidad , Femenino , Estado de Salud , Humanos , Calidad de Vida , Rango del Movimiento Articular
9.
J Biol Chem ; 289(37): 25431-44, 2014 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-25086032

RESUMEN

The evolution of the cancer cell into a metastatic entity is the major cause of death in patients with cancer. It has been acknowledged that aberrant activation of a latent embryonic program, known as the epithelial-mesenchymal transition (EMT), can endow cancer cells with the migratory and invasive capabilities associated with metastatic competence for which E-cadherin switch is a well-established hallmark. Discerning the molecular mechanisms that regulate E-cadherin expression is therefore critical for understanding tumor invasiveness and metastasis. Here we report that SMAR1 overexpression inhibits EMT and decelerates the migratory potential of breast cancer cells by up-regulating E-cadherin in a bidirectional manner. While SMAR1-dependent transcriptional repression of Slug by direct recruitment of SMAR1/HDAC1 complex to the matrix attachment region site present in the Slug promoter restores E-cadherin expression, SMAR1 also hinders E-cadherin-MDM2 interaction thereby reducing ubiquitination and degradation of E-cadherin protein. Consistently, siRNA knockdown of SMAR1 expression in these breast cancer cells results in a coordinative action of Slug-mediated repression of E-cadherin transcription, as well as degradation of E-cadherin protein through MDM2, up-regulating breast cancer cell migration. These results indicate a crucial role for SMAR1 in restraining breast cancer cell migration and suggest the candidature of this scaffold matrix-associated region-binding protein as a tumor suppressor.


Asunto(s)
Neoplasias de la Mama/genética , Cadherinas/biosíntesis , Proteínas de Ciclo Celular/biosíntesis , Proteínas de Unión al ADN/biosíntesis , Transición Epitelial-Mesenquimal/genética , Proteínas Nucleares/biosíntesis , Neoplasias de la Mama/patología , Cadherinas/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Histona Desacetilasa 1/genética , Histona Desacetilasa 1/metabolismo , Humanos , Metástasis de la Neoplasia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteolisis , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Factores de Transcripción de la Familia Snail , Factores de Transcripción/genética
10.
Cell Tissue Res ; 361(2): 605-17, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25681278

RESUMEN

We report embryo-induced alterations occurring in endometrial stromal cells (ESCs) during the embryo-attachment stage in bonnet monkeys (Macaca radiata). Laser micro-dissected ESCs obtained from pregnant and non-pregnant animals were compared for levels of selected proliferation and decidualization-associated factors by analysis with quantitative real-time polymerase chain reaction or immunohistochemistry. Stromal cells exhibited extensive cellular proliferation, as indicated by cellular compaction and significantly higher (P < 0.05) levels of proliferating cell nuclear antigen and of estrogen receptor 1, c-Myc, and Cyclin D1 transcripts in pregnant animals as compared with non-pregnant animals. A significant decrease (P < 0.05) was observed in the transcript levels of stromal interleukin-6 (IL-6) in pregnant animals. Cell proliferation was accompanied by a significant increase (P < 0.001) in the levels of decidualization-associated molecules such as IL-1ß in the luminal and glandular epithelium and of stromal insulin-like growth-factor-binding protein-1 (IGFBP-1) and prostaglandin-endoperoxide synthase-2 (PTGS-2) proteins. In pregnant animals, proliferation was evident throughout the gestational stroma, whereas decidualization was more pronounced in the embryo-attachment zone than in the non-attachment zone. To our knowledge, this is the first report of alterations in the endometrial stroma during the embryo-attachment stage in a non-human primate model.


Asunto(s)
Implantación del Embrión , Endometrio/citología , Macaca radiata/embriología , Células del Estroma/citología , Animales , Proliferación Celular , Ciclina D1/análisis , Ciclina D1/genética , Ciclooxigenasa 2/análisis , Ciclooxigenasa 2/genética , Endometrio/metabolismo , Endometrio/ultraestructura , Receptor alfa de Estrógeno/análisis , Receptor alfa de Estrógeno/genética , Receptor beta de Estrógeno/análisis , Receptor beta de Estrógeno/genética , Femenino , Regulación de la Expresión Génica , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/análisis , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Interleucina-1beta/análisis , Interleucina-1beta/genética , Interleucina-6/análisis , Interleucina-6/genética , Macaca radiata/genética , Embarazo , Proteínas Proto-Oncogénicas c-myc/análisis , Proteínas Proto-Oncogénicas c-myc/genética , Células del Estroma/metabolismo , Transcripción Genética
11.
bioRxiv ; 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38328149

RESUMEN

Distinguishing between nectar and non-nectar odors is challenging for animals due to shared compounds and changing ratios in complex mixtures. Changes in nectar production throughout the day and potentially many times within a forager's lifetime add to the complexity. The honeybee olfactory system, containing less than 1000 principal neurons in the early olfactory relay, the antennal lobe (AL), must learn to associate diverse volatile blends with rewards. Previous studies identified plasticity between AL neurons but its role in odor learning remains poorly understood. We used a computational network model and live imaging of the honeybee's AL to explore the neural mechanisms and functions of plasticity in the early olfactory system. Our findings revealed that when trained with a set of rewarded and unrewarded odors, the AL inhibitory network suppresses shared chemical compounds while enhancing responses to distinct compounds. This results in improved pattern separation and a more concise neural code. Our Calcium imaging data support these predictions. Analysis of a Graph Convolutional Network in machine learning performing an odor categorization task revealed a similar mechanism of contrast enhancement. Our model provides insights into how inhibitory plasticity in the early olfactory network reshapes coding for efficient learning of complex odors. Significance Statement: By combining computational modeling, machine learning, and analysis of calcium imaging data, we demonstrate that associative and non-associative plasticity in the honeybee antennal lobe (AL) - first relay of the insect olfactory system - work together to enhance the contrast between rewarded and unrewarded odors. Training the AL's inhibitory network within specific odor environments enables the suppression of neural responses to common odor components, while amplifying responses to distinctive ones. This study sheds light on the olfactory system's ability to adapt and efficiently learn new odor-reward associations across varying environments, and it proposes innovative, energy-efficient principles applicable to artificial intelligence.

12.
Eur Heart J Cardiovasc Imaging ; 25(10): 1441-1450, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-38860493

RESUMEN

AIMS: Transthoracic echocardiography is recommended in all patients with acute coronary syndrome but is time-consuming and lacks an evidence base. We aimed to assess the feasibility, diagnostic accuracy, and time efficiency of hand-held echocardiography in patients with acute coronary syndrome and describe the impact of echocardiography on clinical management in this setting. METHODS AND RESULTS: Patients with acute coronary syndrome underwent both hand-held and transthoracic echocardiographies with agreement between key imaging parameters assessed using kappa statistics. The immediate clinical impact of hand-held echocardiography in this population was systematically evaluated. Overall, 262 patients (65 ± 12 years, 71% male) participated. Agreement between hand-held and transthoracic echocardiographies was good-to-excellent (kappa 0.60-1.00) with hand-held echocardiography having an overall negative predictive value of 95%. Hand-held echocardiography was performed rapidly (7.7 ± 1.6 min) and completed a median of 5 (interquartile range 3-20) h earlier than transthoracic echocardiography. Systematic hand-held echocardiography in all patients with acute coronary syndrome identified an important cardiac abnormality in 50%, and the clinical management plan was changed by echocardiography in 42%. In 85% of cases, hand-held echocardiography was sufficient for patient decision-making, and transthoracic echocardiography was no longer deemed necessary. CONCLUSION: In patients with acute coronary syndrome, hand-held echocardiography provides comparable results to transthoracic echocardiography, can be more rapidly applied, and gives sufficient imaging information for decision-making in the vast majority of patients. Systematic echocardiography has clinical impact in half of patients, supporting the clinical utility of echocardiography in this population and providing an evidence base for current guidelines.


Asunto(s)
Síndrome Coronario Agudo , Ecocardiografía , Humanos , Síndrome Coronario Agudo/diagnóstico por imagen , Masculino , Femenino , Ecocardiografía/métodos , Anciano , Persona de Mediana Edad , Estudios de Factibilidad , Hospitalización , Estudios de Cohortes
13.
Nat Nanotechnol ; 19(5): 705-714, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38366225

RESUMEN

Graphene oxide nanomaterials are being developed for wide-ranging applications but are associated with potential safety concerns for human health. We conducted a double-blind randomized controlled study to determine how the inhalation of graphene oxide nanosheets affects acute pulmonary and cardiovascular function. Small and ultrasmall graphene oxide nanosheets at a concentration of 200 µg m-3 or filtered air were inhaled for 2 h by 14 young healthy volunteers in repeated visits. Overall, graphene oxide nanosheet exposure was well tolerated with no adverse effects. Heart rate, blood pressure, lung function and inflammatory markers were unaffected irrespective of graphene oxide particle size. Highly enriched blood proteomics analysis revealed very few differential plasma proteins and thrombus formation was mildly increased in an ex vivo model of arterial injury. Overall, acute inhalation of highly purified and thin nanometre-sized graphene oxide nanosheets was not associated with overt detrimental effects in healthy humans. These findings demonstrate the feasibility of carefully controlled human exposures at a clinical setting for risk assessment of graphene oxide, and lay the foundations for investigating the effects of other two-dimensional nanomaterials in humans. Clinicaltrials.gov ref: NCT03659864.


Asunto(s)
Grafito , Nanoestructuras , Humanos , Grafito/química , Masculino , Adulto , Femenino , Nanoestructuras/química , Adulto Joven , Método Doble Ciego , Frecuencia Cardíaca/efectos de los fármacos , Administración por Inhalación , Exposición por Inhalación/efectos adversos , Presión Sanguínea/efectos de los fármacos , Tamaño de la Partícula
14.
Artículo en Inglés | MEDLINE | ID: mdl-39115499

RESUMEN

BACKGROUND: Aortic stenosis (AS) is characterized by calcification and fibrosis. The ability to quantify these processes simultaneously has been limited with previous imaging methods. OBJECTIVES: The purpose of this study was to evaluate the aortic valve fibrocalcific volume by computed tomography (CT) angiography in patients with AS, in particular, to assess its reproducibility, association with histology and disease severity, and ability to predict/track progression. METHODS: In 136 patients with AS, fibrocalcific volume was calculated on CT angiograms at baseline and after 1 year. CT attenuation distributions were analyzed using Gaussian-mixture-modeling to derive thresholds for tissue types enabling the quantification of calcific, noncalcific, and fibrocalcific volumes. Scan-rescan reproducibility was assessed and validation provided against histology and in an external cohort. RESULTS: Fibrocalcific volume measurements took 5.8 ± 1.0 min/scan, demonstrating good correlation with ex vivo valve weight (r = 0.51; P < 0.001) and excellent scan-rescan reproducibility (mean difference -1%, limits of agreement -4.5% to 2.8%). Baseline fibrocalcific volumes correlated with mean gradient on echocardiography in both male and female participants (rho = 0.64 and 0.69, respectively; both P < 0.001) and in the external validation cohort (n = 66, rho = 0.58; P < 0.001). The relationship was driven principally by calcific volume in men and fibrotic volume in women. After 1 year, fibrocalcific volume increased by 17% and correlated with progression in mean gradient (rho = 0.32; P = 0.003). Baseline fibrocalcific volume was the strongest predictor of subsequent mean gradient progression, with a particularly strong association in female patients (rho = 0.75; P < 0.001). CONCLUSIONS: The aortic valve fibrocalcific volume provides an anatomic assessment of AS severity that can track disease progression precisely. It correlates with disease severity and hemodynamic progression in both male and female patients.

15.
Cureus ; 15(3): e36758, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37123765

RESUMEN

This systematic review summarises the findings in the literature available to show outcomes of high tibial osteotomy (HTO) with bone grafting in smokers. It also studies the trend of complications, outcome measures used and overall outcomes like union, non-union or the need to perform revision surgeries. The aim is to find out if HTO done with bone grafting improves outcomes in smokers. Articles were shortlisted using Population, Intervention, Control, and Outcomes (PICO) search design and quality assessment was completed using Jadad, STROBE (Strengthening the Reporting of Observational studies in Epidemiology), Delphi, and Critical Appraisal Skills Program (CASP) followed by data extraction by two independent authors. There was union in 97.6% of smokers who received HTO with bone grafting. A case of non-union was treated with removal of metalwork and distraction osteogenesis. Three cases of unknown demographics had arthroplasty in the time frame from HTO with bone grafting to follow up. The commonest complication post surgery was metalwork causing soft tissue irritation and lateral proximal tibial cortex fracture. Following this review we can conclude that HTO with bone grafting could be considered as an option to achieve better outcomes in smokers. Bone grafting helps healing across osteotomy sites in smokers whose healing potential is poor. Autogenous Iliac crest bone grafting is ideal due to its osteoinductive and osteoconductive properties, but has the disadvantage of donor site morbidity.

16.
Elife ; 122023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36719272

RESUMEN

Odorants binding to olfactory receptor neurons (ORNs) trigger bursts of action potentials, providing the brain with its only experience of the olfactory environment. Our recordings made in vivo from locust ORNs showed that odor-elicited firing patterns comprise four distinct response motifs, each defined by a reliable temporal profile. Different odorants could elicit different response motifs from a given ORN, a property we term motif switching. Further, each motif undergoes its own form of sensory adaptation when activated by repeated plume-like odor pulses. A computational model constrained by our recordings revealed that organizing responses into multiple motifs provides substantial benefits for classifying odors and processing complex odor plumes: each motif contributes uniquely to encode the plume's composition and structure. Multiple motifs and motif switching further improve odor classification by expanding coding dimensionality. Our model demonstrated that these response features could provide benefits for olfactory navigation, including determining the distance to an odor source.


Asunto(s)
Neuronas Receptoras Olfatorias , Neuronas Receptoras Olfatorias/fisiología , Olfato/fisiología , Odorantes , Potenciales de Acción/fisiología , Encéfalo
17.
Eur Heart J Cardiovasc Imaging ; 24(12): 1583-1592, 2023 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-37463125

RESUMEN

AIMS: Speckle-tracking echocardiography (STE) strain imaging has been a major advancement in myocardial function quantification. We aimed to explore current worldwide clinical application of STE. METHODS AND RESULTS: Access, feasibility, access, and clinical implementation of STE were investigated with a worldwide open-access online survey of the European Association of Cardiovascular Imaging. Participants (429 respondents and 77 countries) from tertiary centres (46%), private clinics, or public hospitals (54%) using different vendors for data acquisition and analysis were represented. Despite almost universal access (98%) to STE, only 39% of the participants performed and reported STE results frequently (>50%). Incomplete training and time constraints were the main reasons for not using STE more regularly. STE was mainly used to assess the LV (99%) and less frequently the right ventricular (57%) and the left atrial (46%) function. Cardiotoxicity (88%) and cardiac amyloidosis (87%) were the most frequent reasons for the clinical use of LV STE. Left atrial STE was used most frequently for the diagnosis of diastolic dysfunction and right ventricular STE for the assessment of right ventricle (RV) function in pulmonary hypertension (51%). Frequency of STE use, adherence to optimal techniques, and clinical appropriateness of STE differed according to training experience and across vendors. Key suggestions outlined by respondents to increase the clinical use of STE included improved reproducibility (48%) and standardization of strain values across vendors (42%). CONCLUSION: Although STE is now readily available, it is underutilized in the majority of centres. Structured training, improved reproducibility, and inter-vendor standardization may increase its uptake.


Asunto(s)
Fibrilación Atrial , Humanos , Reproducibilidad de los Resultados , Ecocardiografía/métodos , Ventrículos Cardíacos/diagnóstico por imagen , Atrios Cardíacos , Función Ventricular Izquierda
18.
Eur Heart J Cardiovasc Imaging ; 24(11): 1444-1449, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37409644

RESUMEN

AIMS: The EACVI Scientific Initiatives Committee and the EACVI women's taskforce conducted a global survey to evaluate the barriers faced by women in cardiovascular imaging (WICVi). METHODS AND RESULTS: In a prospective international survey, we assessed the barriers faced at work by WICVi. Three hundred fourteen participants from 53 countries responded. The majority were married (77%) and had children (68%), but most reported no flexibility in their work schedule during their pregnancy or after their maternity leave. More than half of the women reported experiencing unconscious bias (68%), verbal harassment (59%), conscious bias (51%), anxiety (70%), lack of motivation (60%), imposter syndrome (54%), and burnout (61%) at work. Furthermore, one in five respondents had experienced sexual harassment, although this was rarely reported formally. The majority reported availability of mentorship (73%), which was mostly rated as 'good' or 'very good'. While more than two-thirds of respondents (69%) now reported being well trained and qualified to take on leadership roles in their departments, only one-third had been afforded that opportunity. Despite the issues highlighted by this survey, >80% of the participating WICVi would still choose cardiovascular imaging if they could restart their career. CONCLUSION: The survey has highlighted important issues faced by WICVi. While progress has been made in areas such as mentorship and training, other issues including bullying, bias, and sexual harassment are still widely prevalent requiring urgent action by the global cardiovascular imaging community to collectively address and resolve these challenges.


Asunto(s)
Acoso Sexual , Niño , Humanos , Femenino , Embarazo , Estudios Prospectivos , Encuestas y Cuestionarios
19.
Histochem Cell Biol ; 138(2): 289-304, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22527696

RESUMEN

The present investigation reports embryo-induced modifications in the epithelial cells of the endometrium in a primate species. In vivo, epithelial cell response to the embryonic signals was assessed at the embryo attachment stage in the gestational uterus of bonnet monkeys (Macaca radiata) and in vitro response was investigated by treating human endometrial epithelial cell line (Ishikawa) with human embryo conditioned media (CM). Endometrial epithelial (EE) cells at the embryo attachment stage in bonnet monkeys revealed higher proliferation accompanied by significant up regulation (p < 0.05) in the expression of estrogen receptor (ER)α and down regulation (p < 0.05) in ERß expression. Further gestational EE cells showed higher (p < 0.001) expression of mucin-1, except in the embryo attachment site. Also, observed were significantly higher expression (p < 0.05) and altered cytoplasmic distribution of α(v) and ß(3) integrins, when compared to non-pregnant animals. In pregnant animals, the embryo attachment zone showed differential expression of immunoreactive integrins as compared to the non-attachment zone. This suggested the role of embryo secreted factors in modulation of the epithelial cell profile. In vitro studies partially supported this assumption. Significantly higher proliferation (p < 0.05), as well as increased expression of ERα, integrin ß(3) and mucin-1 (p < 0.05) were observed in Ishikawa cells, on stimulation with CM. Taken together, these results indicated the proliferation and modulation in the expression of estrogen receptors and cell adhesion molecules in the EE cells; at the embryo attachment stage in bonnet monkeys. Further it is likely that embryo secreted factors contribute to some of these modifications in EE cells. This report is the first account of discrete cellular events, which occur in the uterine epithelium, at the embryo attachment stage in a primate species.


Asunto(s)
Embrión de Mamíferos/metabolismo , Endometrio/metabolismo , Células Epiteliales/metabolismo , Animales , Moléculas de Adhesión Celular/metabolismo , Línea Celular , Endometrio/embriología , Femenino , Citometría de Flujo , Humanos , Integrinas/metabolismo , Macaca radiata , Mucina-1/metabolismo
20.
Heart ; 108(16): 1267-1273, 2022 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-35074847

RESUMEN

Air pollution is associated with up to 8.8 million excess deaths worldwide each year and is a major contributor to the global burden of disease. Cardiovascular conditions are the predominant cause for air pollution-related deaths and there is an urgent need to address the silent pandemic of air pollution on cardiovascular health. Air pollution exposure is associated with acute events like acute coronary syndrome and stroke, and with chronic conditions, such as atherosclerosis and heart failure. Several potential mechanisms have been proposed that link particle inhalation to cardiovascular disease including oxidative stress and inflammation, changes in autonomic balance and neuroendocrine regulation and the particle translocation into the circulation itself. This, in turn, can cause endothelial, vasomotor and fibrinolytic dysfunction and increased thrombogenicity and blood pressure which are implicated in the mediation of adverse cardiovascular events. Certain interventions can help mitigate these adverse effects. At an individual level, this includes the use of a facemask and indoor air purification systems. At an environmental level, interventions reducing the generation or release of combustion-derived pollutants are key and include public health policies to facilitate active transport, cleaner sources of energy and reductions in vehicular and fossil fuel emissions. In this review, we summarise the key pathways and mechanisms that draw together how air pollution can lead to adverse cardiovascular effects, as well as explore potential interventions to reduce the burden of air pollution-induced cardiovascular morbidity and mortality.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Enfermedades Cardiovasculares , Sistema Cardiovascular , Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Humanos , Pulmón , Material Particulado/efectos adversos
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