High-Efficiency Interdigitated Electrode-Based Droplet Merger for Enabling Error-Free Droplet Microfluidic Systems.

Merging two droplets into a droplet to add and mix two contents is one of the common droplet microfluidic functions with droplet generation and sorting, performing broad ranges of biological and chemical assays in droplets. However, traditional droplet-merging techniques often encounter unsynchronized droplets, causing overmerging or mis-merging, and unwanted merging outside of the desired zone. This is more severe when the incoming droplets to be merged are polydisperse in their sizes, often observed in assays that require long-term incubation, elevated-temperature, and/or multiple droplet processing steps. Here, we developed an interdigitated electrode (IDE)-based droplet merger consisting of a droplet autosynchronizing channel and a merging channel. The autosynchronizing channel provides >95% merging efficiency even when 20% polydispersity in the droplet size exists. The highly localized and enhanced dielectrophoretic force generated by the IDEs on the channel bottom allows droplet merging at an extremely low voltage (4.5 V) and only locally at the IDE region. A systematic evaluation of how various design and operation parameters of the IDE merger, such as IDE finger dimensions, dielectric coating layer thickness, droplet size, and droplet flow speed impact the performance was conducted. The optimized device showed consistent performance even when operating for up to 100 h consecutively at high throughput (100 droplets/s). The presented technology has been integrated into a droplet microfluidics workflow to test the lytic activities of bacteriophage on bacterial host cells with 100% merging efficiency. We expect this function to be integrated into droplet microfluidic systems performing broad ranges of high-throughput chemical and biological assays.

Heart rate variability-based prediction of early cardiotoxicity in breast-cancer patients treated with anthracyclines and trastuzumab.

BACKGROUND: Cardiotoxicity is a recognized complication in breast cancer (BC) patients undergoing chemotherapy with anthracyclines with or without trastuzumab. However, the prognostic value of heart rate variability (HRV) indexes for early cardiotoxicity development remains unknown. METHODS: Fifty BC patients underwent TTE assessment before and three months after chemotherapy. HRV indexes were obtained from continuous electrocardiograms in supine position with spontaneous breathing, active standing, and supine position with controlled breathing. The magnitude of change (Δ) between supine-standing and supine-controlled breathing was calculated. Variables were compared using t-test or ANOVA. Cardiotoxicity predictive value was assessed by ROC curve analysis. A p value of < 0.05 was considered significant. RESULTS: TTE revealed reduced left atrial conduit strain in the cardiotoxicity group. Mean heart rate increased during all maneuvers at follow-up, with no differences in HRV indexes between patients with or without cardiotoxicity. However, a lower Δ in supine-controlled breathing of several HRV indexes predicted early cardiotoxicity identified by echocardiography (e.g. SDNN ≤ -8.44 ms: Sensitivity = 75%, Specificity = 69%). CONCLUSIONS: BC patients treated with chemotherapy maintain cardiac autonomic responses to physiological stimuli after 3 months of chemotherapy. However, a lower Δ during active standing and controlled breathing before chemotherapy may predict early cardiotoxicity.

Comorbidities and clinical symptoms can modify myocardial function: a cross-sectional study with PET/CT / Comorbilidades y síntomas clínicos que pueden modificar la función miocárdica: estudio transversal con PET/TC

Abstract Objective: Associating comorbidities and cardiac symptoms that alter myocardial mechanical function could help clinicians to correctly identify at-risk population. Methods: We conducted a functional open population cross-sectional study of patients referred to a positron emission tomography/computed tomography unit in Mexico City for evaluation of myocardial function, perfusion, and coronary circulation. Ischemia was defined as a sum difference score ≥ 2. Association between comorbidities and cardiac symptoms was tested using logistic regression models and trend analysis. We performed an interaction analysis to evaluate the addition of any accompanying symptoms to comorbid conditions on impairment of myocardial function. Results: One thousand two hundred and seventy-three patients were enrolled, 66.1% male, with a mean age of 62.4 (± 12.7) years, 360 (28.7%) with ischemia, 925 (72.7%) with at least one comorbidity, and 676 (53.1%) had at least one associated cardiac symptom. Patients without ischemia, type 2 diabetes, arterial hypertension, and adverse cardiac symptoms were associated with adverse mechanical, perfusion, and coronary flow parameters. We observed a trend of a cumulative number of comorbidities and cardiac symptoms with increased ischemia and decreased coronary flow. Only in decreased left ventricular ejection fraction, we demonstrated an interaction effect between increased comorbidities and adverse symptoms. Conclusion: The high burden of comorbidities and symptoms in our population alters myocardial function regardless of the level of ischemia.

Resumen Objetivo: La asociación de comorbilidades y síntomas cardíacos que alteran la función miocárdica podría ayudar a los médicos a identificar correctamente a poblaciones de riesgo. Métodos: Se realizó un estudio transversal en población abierta de pacientes referidos a una unidad de PET/CT en la Ciudad de México para evaluación de la función miocárdica, perfusión y circulación coronaria. La isquemia se definió como una suma de diferencia de puntuación (SDS) ≥ 2. La asociación entre las comorbilidades y los síntomas cardíacos se fundamentó mediante modelos de regresión logística y análisis de tendencias. Realizamos un análisis de interacción para evaluar la adición de cualquier síntoma acompañante a condiciones comórbidas en el deterioro de la función miocárdica. Resultados: Se incluyeron 1.273 pacientes, 66,1% del sexo masculino, con una edad media de 62,4 (± 12.7) años, 360 (28,7%) con isquemia, 925 (72,7%) con al menos una comorbilidad y 676 (53,1%) con al menos una menos un síntoma cardíaco asociado. En pacientes sin isquemia, la diabetes mellitus tipo 2, la hipertensión arterial y los síntomas cardíacos adversos se asociaron con parámetros mecánicos, de perfusión y de flujo coronario adversos. Se observó una tendencia con el número acumulado de comorbilidades y síntomas cardíacos con aumento de la isquemia y disminución del flujo coronario. Solo en la disminución de la FEVI se demostró un efecto de interacción entre el aumento de las comorbilidades y los síntomas adversos. Conclusión: La alta carga de comorbilidades y síntomas en nuestra población altera la función miocárdica independientemente del nivel de isquemia.

Right Ventricular Apical Hypertrophic Cardiomyopathy in Association With Infundibular, Valvular, and Supravalvular Pulmonary Stenosis.

A 31-year-old man was referred to our hospital because of exertional dyspnea and palpitations. Cardiac examination revealed a systolic murmur in the pulmonic area. Owing to the suspicion of pulmonary stenosis, cardiac magnetic resonance was notable for apical hypertrophy of the right ventricle and mixed pulmonary stenosis. (Level of Difficulty: Intermediate.).

Cardiovascular diagnostic methods in patients with diabetes mellitus. A review.

Cardiovascular diseases are the most common cause of mortality in the world. Currently, type 2 diabetes mellitus (T2DM) is one of the main risk factors for major adverse cardiovascular events. T2DM patients have a four-fold higher risk of developing heart failure and 10 to 12 times higher mortality. Echocardiography in all its modalities is the best clinical tool for heart failure diagnosis, since it provides static and dynamic images of the heart that allow to identify structural and functional changes, such as pressure variations, flow changes, left ventricular ejection fraction and myocardial surfaces anatomical remodeling.

Las enfermedades cardiovasculares constituyen la causa más común de mortalidad en el mundo. Actualmente, la diabetes mellitus tipo 2 (DM2) representa uno de los principales factores de riesgo de eventos adversos cardiovasculares mayores. Los pacientes que las padecen tienen un riesgo cuatro veces mayor de desarrollar insuficiencia cardíaca y una mortalidad de 10 a 12 veces mayor. La ecocardiografía en todas sus modalidades es la mejor herramienta clínica para el diagnóstico de la insuficiencia cardíaca, ya que proporciona imágenes estáticas y dinámicas del corazón que permiten identificar cambios estructurales y funcionales, como alteraciones en las presiones, cambios de flujo, fracción de expulsión del ventrículo izquierdo y remodelación anatómica de las superficies miocárdicas.

Spectrum of the anomalous origin of the coronary arteries.

The anomalous origin of the coronary arteries (AOCA) has several patterns. Most are functional and asymptomatic. However, some are associated with persistent chest pain and sudden cardiac death. Multiple imaging techniques are available for the assessment of AOCA. We present a report of 4 cases with AOCA, including the anomalous aortic origin of a coronary artery (AAOCA) of the right coronary artery, AAOCA of the circumflex artery, AAOCA of the left anterior descending artery, and AAOCA of the circumflex artery with retroaortic trajectory, in which the clinical manifestations throughout the cases are discussed, highlighting the similarity among patients despite having different patterns. Multiple imaging techniques are indispensable for assessing AOCA, where transthoracic echocardiogram is the first-line study, and cardiac computed tomography provides detailed cardiac and coronary anatomy.

Métodos diagnósticos cardiovasculares en pacientes con diabetes mellitus. Revisión / Cardiovascular diagnostic methods in patients with diabetes mellitus. A review

Resumen Las enfermedades cardiovasculares constituyen la causa más común de mortalidad en el mundo. Actualmente, la diabetes mellitus tipo 2 (DM2) representa uno de los principales factores de riesgo de eventos adversos cardiovasculares mayores. Los pacientes que las padecen tienen un riesgo cuatro veces mayor de desarrollar insuficiencia cardíaca y una mortalidad de 10 a 12 veces mayor. La ecocardiografía en todas sus modalidades es la mejor herramienta clínica para el diagnóstico de la insuficiencia cardíaca, ya que proporciona imágenes estáticas y dinámicas del corazón que permiten identificar cambios estructurales y funcionales, como alteraciones en las presiones, cambios de flujo, fracción de expulsión del ventrículo izquierdo y remodelación anatómica de las superficies miocárdicas.

Abstract Cardiovascular diseases are the most common cause of mortality in the world. Currently, type 2 diabetes mellitus (T2DM) is one of the main risk factors for major adverse cardiovascular events. T2DM patients have a four-fold higher risk of developing heart failure and 10 to 12 times higher mortality. Echocardiography in all its modalities is the best clinical tool for heart failure diagnosis, since it provides static and dynamic images of the heart that allow to identify structural and functional changes, such as pressure variations, flow changes, left ventricular ejection fraction and myocardial surfaces anatomical remodeling.

Assessment of Left Ventricular Myocardial Fibrosis in Adult Patients With Ebstein Anomaly: A Retrospective Cohort Study Based on Cardiac Magnetic Resonance and Histopathological Samples.

BACKGROUND: The association between Ebstein anomaly and myocardial fibrosis, particularly in the left ventricle, has been controversial. We aimed to assess the prevalence of replacement fibrosis with a focus on the left ventricle (LV) using cardiac magnetic resonance (CMR), make a histopathological association between LV fibrosis and CMR findings, and explore whether LV fibrosis is an independent risk factor for cardiovascular disease mortality using a derived risk score. METHODS: We performed a 12-year (2009-2021) retrospective cohort of adult patients with Ebstein anomaly who underwent CMR. The CMR evaluation included a comprehensive assessment of myocardial fibrosis by late gadolinium enhancement (LGE). Four postmortem samples were obtained from our cohort and stained using Masson trichrome to characterize LV fibrosis. We used Cox-regression analysis to identify and derive a prediction score that associated LV fibrosis with cardiovascular disease mortality. RESULTS: We included 57 adults with Ebstein anomaly (52% men; median age, 29.52 [interquartile range, 21.24-39.17] years), of whom 12 died during follow-up. LGE prevalence by CMR was observed in 52.6% in any chamber; LV-LGE in 29.8%. Histopathological findings revealed a mid-wall pattern with predominantly interstitial fibrosis and minimal replacement fibrosis. LV-LGE was associated with increased risk of cardiovascular disease mortality (hazard ratio, 6.02 [95% CI, 1.22-19.91]) attributable to lateral and mid-wall LV segment involvement. Our mortality score achieved an overall good prediction capacity (R2, 0.435; C statistic, 0.93; Dxy, 0.86). CONCLUSIONS: There is a high prevalence of LV fibrosis replacement in adults with Ebstein anomaly, characterized by specific CMR and histological patterns. Furthermore, LV-LGE fibrosis is an independent predictor of cardiovascular disease mortality, which could be integrated into risk assessment in clinical management.

Sphingosine-1-phosphate regulation of luteinising hormone-induced steroidogenesis and proliferation of bovine theca cells in vitro.

CONTEXT: Sphingosine-1-phosphate (S1P) is synthesised by follicle granulosa cells under the influence of follicle-stimulating hormone and seems to be necessary for the biological effects of this gonadotrophin. AIMS: To determine if luteinising hormone (LH) increases S1P production and if this sphingolipid, either induced by LH or added to culture media, regulates steroidogenesis and cell viability in bovine theca cells. METHODS: We used bovine theca cell cultures treated with: S1P (0, 0.1, 1 and 10µM; Experiment 1), LH (0, 0.02, 0.2 and 2ngmL-1 ; Experiment 2) and LH (0.02ngmL-1 ) plus a sphingosine kinase inhibitor (SKI-178; 0, 5 and 10µM; Experiment 3). KEY RESULTS: Treatment with S1P did not affect (P >0.05) theca cell viability or their ability to produce progesterone and testosterone. LH (0.02ngmL-1 ) increased (P <0.05) S1P production, and stimulated the expression of phosphorylated sphingosine kinase-1 (pSPHK1). However, the inhibition of SPHK1, by a specific SPHK1 inhibitor (SKI-178), reduced (P <0.05) cell viability and progesterone secretion. Additionally, the use of SKI-178 increased theca cell testosterone production (P<0.05). CONCLUSIONS: S1P added to culture media did not affect cell viability or steroid synthesis. However, LH stimulated the production of S1P, by increasing phosphorylation of SPHK1 in theca cells. This intracellular S1P was inhibitory on testosterone production but augmented progesterone and viable cell number. IMPLICATIONS: These results suggest a novel signalling pathway for LH in theca cells and underline the importance of S1P in the regulation of steroid synthesis.

Cardiac computed tomography assessment of congenital aortic diseases: a case series.

Background: Congenital aortic diseases (CAoD) encompass a wide variety of disorders that range from asymptomatic findings to life-threatening conditions. Multiple imaging techniques are available for the assessment of CAoD. Case summary: We present seven case reports of congenital aortic diseases, including obstructions in the aortic arch (coarctation, hypoplasia, and interruption) and vascular rings, in which the clinical manifestations throughout the cases are discussed, highlighting the heterogeneity of the symptoms. Discussion: Multi-imaging techniques are indispensable for the assessment of CAoD, where cardiac computed tomography angiography is the main modality for rapid acquisition of three-dimensional volume-rendered images for optimal surgical planning.

Hidden problems in a case of atrial fibrillation.

Atrial fibrillation (AF) is the most common cardiac arrhythmia. However, the relation between congenital heart defects and the predisposition to AF is not fully understood. A 65-year-old male was admitted into the emergency department due to progressive dyspnea, orthopnea, palpitations, and edema. Transthoracic echocardiogram showed bi-atrial enlargement and dysplasia of the mitral leaflets with severe mitral regurgitation. Also, a membrane was noted in the LA, dividing the chamber into two parts, suggestive of cor triatriatum sinister. Coronary computed tomography angiography demonstrated a soft tissue septum in the left atrium. Multimodal evaluation is of vital importance for a complete approach, since, detected in time, it has an excellent prognosis.

The vascular endothelial growth factor (VEGF) system as a key regulator of ovarian follicle angiogenesis and growth.

The vascular endothelial growth factor-A (VEGFA) system is a complex set of proteins, with multiple isoforms and receptors, including both angiogenic (VEGFxxx, VEGFR2) and antiangiogenic members (VEGFxxxb, VEGFR1 and soluble forms of VEGFR). The members of the VEGF system affect the proliferation, survival, and migration of endothelial and nonendothelial cells and are involved in the regulation of follicular angiogenesis and development. The production of VEGF by secondary follicles stimulates preantral follicular development by directly affecting follicular cells and promoting the acquisition of the follicular vasculature and downstream antrum formation. Additionally, the pattern of expression of the components of the VEGF system may provide a proangiogenic milieu capable of triggering angiogenesis and stimulating follicular cells to promote antral follicle growth, whereas, during atresia, this milieu becomes antiangiogenic and blocks follicular development.

Soil Properties Correlate with Microbial Community Structure in Qatari Arid Soils.

This is the first detailed characterization of the microbiota and chemistry of different arid habitats from the State of Qatar. Analysis of bacterial 16S rRNA gene sequences showed that in aggregate, the dominant microbial phyla were Actinobacteria (32.3%), Proteobacteria (24.8%), Firmicutes (20.7%), Bacteroidetes (6.3%), and Chloroflexi (3.6%), though individual soils varied widely in the relative abundances of these and other phyla. Alpha diversity measured using feature richness (operational taxonomic units [OTUs]), Shannon's entropy, and Faith's phylogenetic diversity (PD) varied significantly between habitats (P = 0.016, P = 0.016, and P = 0.015, respectively). Sand, clay, and silt were significantly correlated with microbial diversity. Highly significant negative correlations were also seen at the class level between both classes Actinobacteria and Thermoleophilia (phylum Actinobacteria) and total sodium (R = -0.82 and P = 0.001 and R = -0.86, P = 0.000, respectively) and slowly available sodium (R = -0.81 and P = 0.001 and R = -0.8 and P = 0.002, respectively). Additionally, class Actinobacteria also showed significant negative correlation with sodium/calcium ratio (R = -0.81 and P = 0.001). More work is needed to understand if there is a causal relationship between these soil chemical parameters and the relative abundances of these bacteria. IMPORTANCE Soil microbes perform a multitude of essential biological functions, including organic matter decomposition, nutrient cycling, and soil structure preservation. Qatar is one of the most hostile and fragile arid environments on earth and is expected to face a disproportionate impact of climate change in the coming years. Thus, it is critical to establish a baseline understanding of microbial community composition and to assess how soil edaphic factors correlate with microbial community composition in this region. Although some previous studies have quantified culturable microbes in specific Qatari habitats, this approach has serious limitations, as in environmental samples, approximately only 0.5% of cells are culturable. Hence, this method vastly underestimates natural diversity within these habitats. Our study is the first to systematically characterize the chemistry and total microbiota associated with different habitats present in the State of Qatar.

Diagnosis, performance and added value of assessing ventricular dyssynchrony by phase analysis in patients with three-vessel disease: A single-center cross-sectional study in Mexico.

BACKGROUND: Three-vessel disease (3VD) is a cardiovascular disorder that affects the three main coronary arteries. Gated myocardial perfusion SPECT (GMPS) evaluates ventricular function, synchrony, and myocardial perfusion. However, the diagnostic performance of GMPS parameters to assess 3VD has not been fully explored. AIMS: To assess the univariate performance capacity of GMPS parameters, and to evaluate whether phase parameters could provide additional predictive value for the detection of patients with 3VD compared to control subjects. METHODS: We designed paired retrospective samples of GMPS images of patients with 3VD (stenosis > 70% of left anterior descending, right coronary, and circumflex coronary arteries) and without 3VD. A GMPS in rest-stress protocol was performed using 99mTc-Sestamibi and thallium and analyzed with the 3D method. Area under the receiver-operating characteristic curves (AUROC), decision curve analyses and diagnostic test performance were obtained for univariable analyses and stepwise binomial logistic regression for multivariable performance. RESULTS: 474 Patients were included: 237 with 3VD (84% males, mean age 61.7 ± 9.9 years) and 237 with normal GMPS (51% women, mean age 63.8 ± 10.6 years). The highest AUROC for perfusion parameters were recorded for SSS, SRS and TID. For dyssynchrony parameters, both entropy and bandwidth in rest and stress phases displayed the highest AUROC and diagnostic capacity to detect 3VD. A multivariate model with SRS ≥ 4, SDS ≥ 2, TID > 1.19 and sBW ≥ 48° displayed the highest diagnostic capacity (0.923 [95% CI 0.897-0.923]) to detect 3VD. CONCLUSION: Perfusion and dyssynchrony were the parameters which were most able to discriminate patients with 3VD from those who did not have CAD.

Comorbidities and cardiac symptoms can modify myocardial function regardless of ischemia: a cross-sectional study with PET/CT.

Objective: Associating comorbidities and cardiac symptoms that alter myocardial mechanical function could help clinicians to correctly identify at-risk population. Methods: We conducted a functional open population cross-sectional study of patients referred to a positron emission computed tomography/computed tomography unit in Mexico City for evaluation of myocardial function, perfusion, and coronary circulation. Ischemia was defined as a sum difference score (SDS) > 2. Association between comorbidities and cardiac symptoms was tested using logistic regression models and trend analysis. We performed an interaction analysis to evaluate the addition of any accompanying symptoms to comorbid conditions on impairment of myocardial function. Results: One thousand two hundred and seventy-three patients were enrolled, 66.1% male, with a mean age of 62.4 (± 12.7) years, 360 (28.7%) with ischemia, 925 (72.7%) with at least one comorbidity, and 676 (53.1%) had at least one associated cardiac symptom. Patients without ischemia, type 2 diabetes, arterial hypertension, and adverse cardiac symptoms were associated with adverse function, perfusion, and coronary flow parameters. We observed a trend of a cumulative number of comorbidities and cardiac symptoms with increased ischemia and decreased coronary flow. Only in decreased LVEF, we demonstrated an interaction effect between increased comorbidities and adverse symptoms. Conclusions: The high burden of comorbidities and symptoms in our population alter myocardial function regardless of the level of ischemia.