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1.
Heart Rhythm ; 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38797305

RESUMO

BACKGROUND: Despite the implantable cardioverter defibrillator's (ICD) effectiveness in saving patients with life-threatening ventricular arrhythmias (VAs), the temporal occurrence of VA following ICD implantation is unpredictable. OBJECTIVE: Apply machine learning (ML) to intracardiac electrograms (IEGMs) recorded by ICDs as a unique biomarker for predicting impending VAs. METHODS: The study included 13,516 patients who received BIOTRONIK ICDs and enrolled in the CERTITUDE registry between 01/01/2010 to 12/31/2020. Database extraction included IEGMs from standard quarterly transmissions and VA event episodes. The processed IEGM data were pulled from device transmissions stored in a centralized Home Monitoring Service Center and reformatted into an analyzable format. Long- (baseline or first scheduled remote recording), mid-(scheduled remote recording every 90 days), or short-range predictions (IEGM within 5 seconds before the VA onset) were used to determine whether ML-processed IEGMs predicted impending VA events. Convolutional neural network classifiers using ResNet architecture were employed. RESULTS: Of 13,516 patients (male 72%, age 67.5 ± 11.9 years), 301,647 IEGM recordings were collected; 27,845 episodes of sustained VT/VF were observed in 4,467 patients (33.0%). Neural networks based on CNN using ResNet-like architectures on far-field IEGMs yielded an AUC of 0.83 with a 95% confidence interval of [0.79, 0.87] in the short-term, while the long- and mid-range analyses had minimal predictive value for VA events. CONCLUSION: In this study, applying ML to ICD-acquired IEGMs predicted impending VT/VF events seconds before they occurred, whereas mid- to long-term predictions were not successful. This could have important implications for future device therapies.

2.
Europace ; 26(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38703372

RESUMO

AIMS: To characterize the diagnosis, frequency, and procedural implications of septal venous channel perforation during left bundle branch area pacing (LBBAP). METHODS AND RESULTS: All consecutive patients undergoing LBBAP over an 8-month period were prospectively studied. During lead placement, obligatory septal contrast injection was performed twice, at initiation (implant entry zone) and at completion (fixation zone). An intuitive fluoroscopic schema using orthogonal views (left anterior oblique/right anterior oblique) and familiar landmarks is described. Using this, we resolved zonal distribution (I-VI) of lead position on the ventricular septum and its angulation (post-fixation angle θ). Subjects with and without septal venous channel perforation were compared. Sixty-one patients {male 57.3%, median age [interquartile range (IQR)] 69.5 [62.5-74.5] years} were enrolled. Septal venous channel perforation was observed in eight (13.1%) patients [male 28.5%, median age (IQR) 64 (50-75) years]. They had higher frequency of (i) right-sided implant (25% vs. 1.9%, P = 0.04), (ii) fixation in zone III at the mid-superior septum (75% vs. 28.3%, P = 0.04), (iii) steeper angle of fixation-median θ (IQR) [19 (10-30)° vs. 5 (4-19)°, P = 0.01], and (iv) longer median penetrated-lead length (IQR) [13 (10-14.8) vs. 10 (8.5-12.5) mm, P = 0.03]. Coronary sinus drainage of contrast was noted in five (62.5%) patients. Abnormal impedance drops during implantation (12.5% vs. 5.7%, P = NS) were not significantly different. CONCLUSION: When evaluated systematically, septal venous channel perforation may be encountered commonly after LBBAP. The fiducial reference framework described using fluoroscopic imaging identified salient associated findings. This may be addressed with lead repositioning to a more inferior location and is not associated with adverse consequence acutely or in early follow-up.


Assuntos
Estimulação Cardíaca Artificial , Humanos , Masculino , Feminino , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso , Estimulação Cardíaca Artificial/métodos , Septo Interventricular/diagnóstico por imagem , Traumatismos Cardíacos/etiologia , Traumatismos Cardíacos/diagnóstico por imagem , Resultado do Tratamento , Fatores de Risco , Fascículo Atrioventricular/fisiopatologia , Septos Cardíacos/diagnóstico por imagem , Meios de Contraste , Fluoroscopia , Bloqueio de Ramo/fisiopatologia , Bloqueio de Ramo/etiologia
3.
J Am Chem Soc ; 146(19): 13377-13390, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38709577

RESUMO

Metal-organic frameworks (MOFs) offer an interesting opportunity for catalysis, particularly for metal-nitrogen-carbon (M-N-C) motifs by providing an organized porous structural pattern and well-defined active sites for the oxygen reduction reaction (ORR), a key need for hydrogen fuel cells and related sustainable energy technologies. In this work, we leverage electrochemical testing with computational models to study the electronic and structural properties in the MOF systems and their relationship to ORR activity and stability based on dual transitional metal centers. The MOFs consist of two M1 metals with amine nodes coordinated to a single M2 metal with a phthalocyanine linker, where M1/M2 = Co, Ni, or Cu. Co-based metal centers, in particular Ni-Co, demonstrate the highest overall activity of all nine tested MOFs. Computationally, we identify the dominance of Co sites, relative higher importance of the M2 site, and the role of layer M1 interactions on the ORR activity. Selectivity measurements indicate that M1 sites of MOFs, particularly Co, exhibit the lowest (<4%), and Ni demonstrates the highest (>46%) two-electron selectivity, in good agreement with computational studies. Direct in situ stability characterization, measuring dissolved metal ions, and calculations, using an alkaline stability metric, confirm that Co is the most stable metal in the MOF, while Cu exhibits notable instability at the M1. Overall, this study reveals how atomistic coupling of electronic and structural properties affects the ORR performance of dual site MOF catalysts and opens new avenues for the tunable design and future development of these systems for practical electrochemical applications.

4.
Eur Heart J Case Rep ; 8(3): ytae106, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38500489

RESUMO

Background: There has been recent growing interest in the use of conduction system pacing (CSP) for both bradycardia and heart failure indications. There remains a paucity of data, however, regarding complications related to the intraventricular septum associated with CSP implant and the management of these events. Case summary: We present a case of a patient with non-ischemic dilated cardiomyopathy presenting for cardiac resynchronization therapy in whom left bundle branch area pacing was complicated with interventricular septal perforation and managed intra-procedurally with repositioning of the lead to provide His bundle pacing (HBP) for QRS correction of underlying left bundle branch block. Post-procedure echocardiography did not show persistent ventricular septal defect. Left ventricular ejection fraction improved from 13% four months before implant to 30% at 32 months post-implant. Corrective HBP pacing thresholds showed a rise at 3-year follow-up. Discussion: Interventricular septal perforation during CSP is a possible complication during lead fixation. Pre-operative septal assessment with imaging can be helpful to provide important septal anatomical features. Septal perforation can be managed appropriately with lead repositioning intra-procedurally and close follow-up.

5.
JAMA Cardiol ; 9(5): 449-456, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38536171

RESUMO

Importance: Current left bundle branch block (LBBB) criteria are based on animal experiments or mathematical models of cardiac tissue conduction and may misclassify patients. Improved criteria would impact referral decisions and device type for cardiac resynchronization therapy. Objective: To develop a simple new criterion for LBBB based on electrophysiological studies of human patients, and then to validate this criterion in an independent population. Design, Setting, and Participants: In this diagnostic study, the derivation cohort was from a single-center, prospective study of patients undergoing electrophysiological study from March 2016 through November 2019. The validation cohort was assembled by retrospectively reviewing medical records for patients from the same center who underwent transcatheter aortic valve replacement (TAVR) from October 2015 through May 2022. Exposures: Patients were classified as having LBBB or intraventricular conduction delay (IVCD) as assessed by intracardiac recording. Main Outcomes and Measures: Sensitivity and specificity of the electrocardiography (ECG) criteria assessed in patients with LBBB or IVCD. Results: A total of 75 patients (median [IQR] age, 63 [53-70.5] years; 21 [28.0%] female) with baseline LBBB on 12-lead ECG underwent intracardiac recording of the left ventricular septum: 48 demonstrated complete conduction block (CCB) and 27 demonstrated intact Purkinje activation (IPA). Analysis of surface ECGs revealed that late notches in the QRS complexes of lateral leads were associated with CCB (40 of 48 patients [83.3%] with CCB vs 13 of 27 patients [48.1%] with IPA had a notch or slur in lead I; P = .003). Receiver operating characteristic curves for all septal and lateral leads were constructed, and lead I displayed the best performance with a time to notch longer than 75 milliseconds. Used in conjunction with the criteria for LBBB from the American College of Cardiology/American Heart Association/Heart Rhythm Society, this criterion had a sensitivity of 71% (95% CI, 56%-83%) and specificity of 74% (95% CI, 54%-89%) in the derivation population, contrasting with a sensitivity of 96% (95% CI, 86%-99%) and specificity of 33% (95% CI, 17%-54%) for the Strauss criteria. In an independent validation cohort of 46 patients (median [IQR] age, 78.5 [70-84] years; 21 [45.7%] female) undergoing TAVR with interval development of new LBBB, the time-to-notch criterion demonstrated a sensitivity of 87% (95% CI, 74%-95%). In the subset of 10 patients with preprocedural IVCD, the criterion correctly distinguished IVCD from LBBB in all cases. Application of the Strauss criteria performed similarly in the validation cohort. Conclusions and Relevance: The findings suggest that time to notch longer than 75 milliseconds in lead I is a simple ECG criterion that, when used in conjunction with standard LBBB criteria, may improve specificity for identifying patients with LBBB from conduction block. This may help inform patient selection for cardiac resynchronization or conduction system pacing.


Assuntos
Bloqueio de Ramo , Eletrocardiografia , Humanos , Bloqueio de Ramo/fisiopatologia , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/terapia , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos
6.
Cureus ; 16(1): e51960, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38333484

RESUMO

Salmonella is an unusual cause of spontaneous bacterial peritonitis (SBP). It is commonly seen in asymptomatic patients with normal or high ascitic fluid protein levels and an immunocompromised state such as AIDS and hematological and solid organ malignancies other than liver. SBP from non-typhoidal Salmonella species should be considered, even in the absence of underlying immunosuppression. Our patient presented with a history of high-grade fever and frequent loose stools with decompensated alcoholic liver cirrhosis. While evaluating the SBP etiology, ascitic fluid turned out positive for the non-typhoidal Salmonella species, which was red, turbid, and hemorrhagic due to portal vein and superior mesenteric vein thrombosis. We thus report an extremely rare case of SBP caused by Salmonella typhimurium in our patient.

7.
Cureus ; 15(8): e44394, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37654905

RESUMO

Introduction This study aims to differentiate the employment of demineralized bone matrix (DMBM; Osseograft, Advanced Biotech Products (P) Ltd, Chennai, India) and platelet-rich fibrin (PRF) alone to a composite graft consisting of both materials in the surgical actions toward the anomalies of the human periodontal furcation imperfection. Methods In a split-mouth study, 30 patients with mandibular molars affected by the furcation were allocated without conscious choice to test (PRF + DMBM, n = 30) or control (PRF, n = 30) categories. At the starting point, three months after surgery, and six months later, the following modifiable factors were evaluated: probing pocket depth (PPD), full-mouth plaque scores, full-mouth gingival scores, radiographic defect depth, relative vertical clinical attachment level (RVCAL), and relative horizontal clinical attachment level (RHCAL). Results Results at three and six months demonstrated substantial differences between baseline values for both treatment methods in clinical and X-ray imaging appraisal. Nonetheless, the PRF/DMBM group manifests statistically significantly soaring changes observed in comparison to the PRF group. Overall, the probing depth (PD) in the test site was significantly lower than that in the control site, showing a reduction of 68% (95% CI=41%, 95%, p<0.001). Conclusion Clinical indications significantly improved with PRF and DMBM combined instead of PRF alone. On radiographs, the test group also showed higher bone fill.

8.
J Am Coll Cardiol ; 82(11): 1096-1105, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37673510

RESUMO

BACKGROUND: Factors determining hemodynamic stability during human ventricular tachycardia (VT) are incompletely understood. OBJECTIVES: The purposes of this study were to characterize sinus rate (SR) responses during monomorphic VT in association with hemodynamic stability and to prospectively assess the effects of vagolytic therapy on VT tolerance. METHODS: This is a retrospective analysis of patients undergoing scar-related VT ablation. Vasovagal responses were evaluated by analyzing sinus cycle length before VT induction and during VT. SR responses were classified into 3 groups: increasing (≥5 beats/min, sympathetic), decreasing (≥5 beats/min, vagal), and unchanged, with the latter 2 categorized as inappropriate SR. In a prospective cohort (n = 30) that exhibited a failure to increase SR, atropine was administered to improve hemodynamic tolerance to VT. RESULTS: In 150 patients, 261 VT episodes were analyzed (29% untolerated, 71% tolerated) with median VT duration 1.6 minutes. A total of 52% of VT episodes were associated with a sympathetic response, 31% had unchanged SR, and 17% of VTs exhibited a vagal response. A significantly higher prevalence of inappropriate SR responses was observed during untolerated VT (sustained VT requiring cardioversion within 150 seconds) compared with tolerated VT (84% vs 34%; P < 0.001). Untolerated VT was significantly different between groups: 9% (sympathetic), 82% (vagal), and 32% (unchanged) (P < 0.001). Atropine administration improved hemodynamic tolerance to VT in 70%. CONCLUSIONS: Nearly one-half of VT episodes are associated with failure to augment SR, indicative of an under-recognized pathophysiological vasovagal response to VT. Inappropriate SR responses were more predictive of hemodynamic instability than VT rate and ejection fraction. Vagolytic therapy may be a novel method to augment blood pressure during VT.


Assuntos
Taquicardia Ventricular , Humanos , Estudos Prospectivos , Estudos Retrospectivos , Taquicardia Ventricular/terapia , Hemodinâmica , Atropina/farmacologia , Ubiquitina-Proteína Ligases
10.
bioRxiv ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37745600

RESUMO

Tumor cells rely on increased glycolytic capacity to promote cell growth and progression. While glycolysis is known to be upregulated in the majority of triple negative (TNBC) or basal-like subtype breast cancers, the mechanism remains unclear. Here, we used integrative genomic analyses to identify a subset of basal-like tumors characterized by increased expression of the oncogenic transcription factor SOX4 and its co-factor the SWI/SNF ATPase SMARCA4. These tumors are defined by unique gene expression programs that correspond with increased tumor proliferation and activation of key metabolic pathways, including glycolysis. Mechanistically, we demonstrate that the SOX4-SMARCA4 complex mediates glycolysis through direct transcriptional regulation of Hexokinase 2 (HK2) and that aberrant HK2 expression and altered glycolytic capacity are required to mediate SOX4-SMARCA4-dependent cell growth. Collectively, we have defined the SOX4-SMARCA4-HK2 signaling axis in basal-like breast tumors and established that this axis promotes metabolic reprogramming which is required to maintain tumor cell growth.

11.
Circulation ; 148(18): 1354-1367, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37638389

RESUMO

BACKGROUND: The circuit boundaries for reentrant ventricular tachycardia (VT) have been historically conceptualized within a 2-dimensional (2D) construct, with their fixed or functional nature unresolved. This study aimed to examine the correlation between localized lines of conduction block (LOB) evident during baseline rhythm with lateral isthmus boundaries that 3-dimensionally constrain the VT isthmus as a hyperboloid structure. METHODS: A total of 175 VT activation maps were correlated with isochronal late activation maps during baseline rhythm in 106 patients who underwent catheter ablation for scar-related VT from 3 centers (42% nonischemic cardiomyopathy). An overt LOB was defined by a deceleration zone with split potentials (≥20 ms isoelectric segment) during baseline rhythm. A novel application of pacing within deceleration zone (≥600 ms) was implemented to unmask a concealed LOB not evident during baseline rhythm. LOB identified during baseline rhythm or pacing were correlated with isthmus boundaries during VT. RESULTS: Among 202 deceleration zones analyzed during baseline rhythm, an overt LOB was evident in 47%. When differential pacing was performed in 38 deceleration zones without overt LOB, an underlying concealed LOB was exposed in 84%. In 152 VT activation maps (2D=53, 3-dimensional [3D]=99), 69% of lateral boundaries colocalized with an LOB in 2D activation patterns, and the depth boundary during 3D VT colocalized with an LOB in 79%. In VT circuits with isthmus regions that colocalized with a U-shaped LOB (n=28), the boundary invariably served as both lateral boundaries in 2D and 3D. Overall, 74% of isthmus boundaries were identifiable as fixed LOB during baseline rhythm or differential pacing. CONCLUSIONS: The majority of VT circuit boundaries can be identified as fixed LOB from intrinsic or paced activation during sinus rhythm. Analysis of activation while pacing within the scar substrate is a novel technique that may unmask concealed LOB, previously interpreted to be functional in nature. An LOB from the perspective of a myocardial surface is frequently associated with intramural conduction, supporting the existence of a 3D hyperboloid VT circuit structure. Catheter ablation may be simplified to targeting both sides around an identified LOB during sinus rhythm.


Assuntos
Ablação por Cateter , Taquicardia Ventricular , Humanos , Cicatriz , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/cirurgia , Arritmias Cardíacas , Frequência Cardíaca/fisiologia , Bloqueio Cardíaco
12.
J Am Coll Cardiol ; 82(5): 383-397, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37495274

RESUMO

BACKGROUND: The subcutaneous implantable cardioverter-defibrillator (S-ICD) was developed to avoid complications related to transvenous implantable cardioverter-defibrillator (TV-ICD) leads. Device safety and efficacy were demonstrated previously with atypical clinical patients or limited follow-up. OBJECTIVES: The S-ICD PAS (Subcutaneous Implantable Cardioverter-Defibrillator System Post Approval Study) is a real-world, multicenter, registry of U.S. centers that was designed to assess long-term S-ICD safety and efficacy in a diverse group of patients and implantation centers. METHODS: Patients were enrolled in 86 U.S. centers with standard S-ICD indications and were observed for up to 5 years. Efficacy endpoints were first and final shock efficacy. Safety endpoints were complications directly related to the S-ICD system or implantation procedure. Endpoints were assessed using prespecified performance goals. RESULTS: A total of 1,643 patients were prospectively enrolled, with a median follow-up of 4.2 years. All prespecified safety and efficacy endpoint goals were met. Shock efficacy rates for discrete episodes of ventricular tachycardia or ventricular fibrillation were 98.4%, and they did not differ significantly across follow-up years (P = 0.68). S-ICD-related and electrode-related complication-free rates were 93.4% and 99.3%, respectively. Only 1.6% of patients had their devices replaced by a TV-ICD for a pacing need. Cumulative all-cause mortality was 21.7%. CONCLUSIONS: In the largest prospective study of the S-ICD to date, all study endpoints were met, despite a cohort with more comorbidities than in most previous trials. Complication rates were low and shock efficacy was high. These results demonstrate the 5-year S-ICD safety and efficacy for a large, diverse cohort of S-ICD recipients. (Subcutaneous Implantable Cardioverter-Defibrillator [S-ICD] System Post Approval Study [PAS]; NCT01736618).


Assuntos
Desfibriladores Implantáveis , Taquicardia Ventricular , Humanos , Resultado do Tratamento , Estudos Prospectivos , Arritmias Cardíacas/terapia , Taquicardia Ventricular/terapia , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/prevenção & controle
13.
Cardiol Clin ; 41(3): 379-391, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37321688

RESUMO

Left bundle branch block (LBBB) is not just a simple electrocardiogram alteration. The intricacies of this general terminology go beyond simple conduction block. This review puts together current knowledge on the historical concept of LBBB, clinical significance, and recent insights into the pathophysiology of human LBBB. LBBB is an entity that affects patient diagnosis (primary conduction disease, secondary to underlying pathology or iatrogenic), treatment (cardiac resynchronization therapy or conduction system pacing for heart failure), and prognosis. Recruiting the left bundle branch with conduction system pacing depends on the complex interaction between anatomy, site of pathophysiology, and delivery tools.


Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Humanos , Bloqueio de Ramo/diagnóstico , Bloqueio de Ramo/terapia , Sistema de Condução Cardíaco , Eletrocardiografia , Prognóstico , Resultado do Tratamento , Função Ventricular Esquerda
14.
Heart Rhythm O2 ; 4(3): 215-222, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36993915

RESUMO

Background: Whether racial disparities in outcomes are present after catheter ablation for scar-related ventricular tachycardia (VT) is not known. Objective: The purpose of this study was to examine whether racial differences exist in outcomes for patients undergoing VT ablation. Methods: From March 2016 through April 2021, consecutive patients undergoing catheter ablation for scar-related VT at the University of Chicago were prospectively enrolled. The primary outcome was VT recurrence, with secondary outcome of mortality alone and composite endpoint of left ventricular assist device placement, heart transplant, or mortality. Results: A total of 258 patients were analyzed: 58 (22%) self-identified as Black, and 113 (44%) had ischemic cardiomyopathy. Black patients had significantly higher rates of hypertension (HTN), chronic kidney disease (CKD), and VT storm at presentation. At 7 months, Black patients experienced higher rates of VT recurrence (P = .009). However, after multivariable adjustment, there were no observed differences in VT recurrence (adjusted hazard ratio [aHR] 1.65; 95% confidence interval [CI] 0.91-2.97; P = .10), all-cause mortality (aHR 0.49; 95% CI 0.21-1.17; P = .11), or composite events (aHR 0.76; 95% CI 0.37-1.54; P = .44) between Black and non-Black patients. Conclusion: In this diverse prospective registry of patients undergoing catheter ablation for scar-related VT, Black patients experienced higher rates of VT recurrence compared to non-Black patients. When adjusted for highly prevalent HTN, CKD, and VT storm, Black patients had comparable outcomes as non-Black patients.

15.
J Am Coll Cardiol ; 81(10): 949-961, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36889873

RESUMO

BACKGROUND: Although implantable cardioverter-defibrillator (ICD) therapies are associated with increased morbidity and mortality, the prediction of malignant ventricular arrhythmias has remained elusive. OBJECTIVES: The purpose of this study was to evaluate whether daily remote-monitoring data may predict appropriate ICD therapies for ventricular tachycardia or ventricular fibrillation. METHODS: This was a post hoc analysis of IMPACT (Randomized trial of atrial arrhythmia monitoring to guide anticoagulation in patients with implanted defibrillator and cardiac resynchronization devices), a multicenter, randomized, controlled trial of 2,718 patients evaluating atrial tachyarrhythmias and anticoagulation for patients with heart failure and ICD or cardiac resynchronization therapy with defibrillator devices. All device therapies were adjudicated as either appropriate (to treat ventricular tachycardia or ventricular fibrillation) or inappropriate (all others). Remote monitoring data in the 30 days before device therapy were utilized to develop separate multivariable logistic regression and neural network models to predict appropriate device therapies. RESULTS: A total of 59,807 device transmissions were available for 2,413 patients (age 64 ± 11 years, 26% women, 64% ICD). Appropriate device therapies (141 shocks, 10 antitachycardia pacing) were delivered to 151 patients. Logistic regression identified shock lead impedance and ventricular ectopy as significantly associated with increased risk of appropriate device therapy (sensitivity 39%, specificity 91%, AUC: 0.72). Neural network modeling yielded significantly better (P < 0.01 for comparison) predictive performance (sensitivity 54%, specificity 96%, AUC: 0.90), and also identified patterns of change in atrial lead impedance, mean heart rate, and patient activity as predictors of appropriate therapies. CONCLUSIONS: Daily remote monitoring data may be utilized to predict malignant ventricular arrhythmias in the 30 days before device therapies. Neural networks complement and enhance conventional approaches to risk stratification.


Assuntos
Fibrilação Atrial , Desfibriladores Implantáveis , Taquicardia Ventricular , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Fibrilação Atrial/terapia , Fibrilação Ventricular/diagnóstico , Fibrilação Ventricular/terapia , Taquicardia Ventricular/diagnóstico , Taquicardia Ventricular/terapia , Taquicardia Ventricular/etiologia , Desfibriladores Implantáveis/efeitos adversos , Anticoagulantes , Resultado do Tratamento
16.
Luminescence ; 38(5): 568-575, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36929687

RESUMO

In the current study, α-Bi2 O3 and ß-Bi2 O3 were synthesised using a one-step, novel, solid-solid combustion technique. The reaction rate was increased with the use of microwaves (molecular heating) compared to direct or indirect heating. A strong relationship was observed between the fuel, polymorphic structure, shape and optical properties of the synthesised Bi2 O3 . Photoluminescence studies reveal that two major visible emissions are observed for all samples. The two emissions are distinct with a broad peak in blue and a narrow peak in green. The intensity of the green characteristic emission depends strongly on the heating method used for synthesis and is more intense for microwave-synthesised samples.


Assuntos
Micro-Ondas
17.
Clin Pharmacol Drug Dev ; 12(2): 202-211, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36065092

RESUMO

ZYIL1 is a nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain-containing 3 (NLRP3) inflammasome inhibitor, which prevents NLRP3-induced apoptosis-associated speck-like protein containing a caspase activation and recruitment domain oligomerization, thus inhibiting NLRP3 inflammasome pathway. We investigated the safety, tolerability, pharmacokinetic, and pharmacodynamic profiles of ZYIL1 after single and multiple doses in healthy subjects. The subjects aged 18-55 years were enrolled in 2 different studies: single and multiple ascending dose. Blood/urine samples were collected at designated time points for pharmacokinetic and pharmacodynamic analysis. In the single-ascending-dose study, 30 subjects were enrolled (6 subjects each in 5 dose groups). One adverse event was reported during the study. ZYIL1 was well absorbed with median time to maximum plasma concentration at 1-1.5 hours. The exposures were dose proportional across the dose ranges. ZYIL1 is excreted as an unchanged form via the renal route. The mean elimination half-life was 6-7 hours. In the multiple-ascending-dose study, 18 subjects were enrolled (6 subjects each in 3 dose groups). Eleven adverse events were reported by 6 subjects during the study. The accumulation index at steady state for area under the plasma concentration-time curve indicated that ZYIL1 has a marginal accumulation upon repeated dosing. Dose-proportional exposure was observed across the dose ranges. All subjects showed >90% interleukin (IL)-1ß inhibition in all dose groups for both studies. Inhibition in IL-1ß and IL-18 was observed throughout the 14 days of treatment in the multiple-dose study. The safety profile, rapid absorption, marginal accumulation, and significant inhibition of IL-1ß and IL-18 level support its development for the management of inflammatory disorders.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Interleucina-18/metabolismo , Área Sob a Curva
18.
Cureus ; 15(12): e51309, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38288229

RESUMO

Clinical laboratories are essential in healthcare to better diagnose, treat, and track medical diseases. However, handling infectious organisms and possibly infectious materials in these laboratories puts the safety of laboratory workers and the general public at risk. By controlling the distribution of infectious substances and stopping the spread of diseases, biosafety cabinets (BSCs) have become crucial tools in guaranteeing laboratory safety. The prevention of infections is most important in medical and laboratory settings. In clinical laboratories, biological and infectious agents are handled, posing threats to healthcare workers and the general public. To avoid infections, proper training of the BSC is essential. Laboratory employees are instructed in aseptic procedures, proper hand posture, and efficient personal protection when working in the cabinet. These instructions decrease the chance of contaminating the surrounding area. Additionally, user ergonomics are taken into account while designing BSC, reducing operator fatigue, and guaranteeing that staff can execute tasks precisely for extended periods. This review highlights the importance of biosafety cabinets in maintaining a secure laboratory environment and explains their crucial function in infection control.

19.
J Am Chem Soc ; 144(49): 22549-22561, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36453840

RESUMO

Improving electrocatalyst stability is critical for the development of electrocatalytic devices. Herein, we utilize an on-line electrochemical flow cell coupled with an inductively coupled plasma-mass spectrometer (ICP-MS) to characterize the impact of composition and reactant gas on the multielement dissolution of Mn(-Cr)-Sb-O electrocatalysts. Compared to Mn2O3 and Cr2O3 oxides, the antimonate framework stabilizes Mn at OER potentials and Cr at both ORR and OER potentials. Furthermore, dissolution of Mn and Cr from Mn(-Cr) -Sb-O is driven by the ORR reaction rate, with minimal dissolution under N2. We observe preferential dissolution of Cr totaling 13% over 10 min at 0.3, 0.6, and 0.9 V vs RHE, with only 1.5% loss of Mn, indicating an enrichment of Mn at the surface of the particles. Despite this asymmetric dissolution, operando X-ray absorption spectroscopy (XAS) showed no measurable changes in the Mn K-edge at comparable potentials. This could suggest that modification to the Mn oxidation state and/or phase in the surface layer is too small or that the layer is too thin to be measured with the bulk XAS measurement. Lastly, on-line ICP-MS was used to assess the effects of applied potential, scan rate, and current on Mn-Cr-Sb-O during cyclic voltammetry and accelerated stress tests. With this deeper understanding of the interplay between oxygen reduction and dissolution, testing procedures were identified to maximize both activity and stability. This work highlights the use of multimodal in situ characterization techniques in tandem to build a more complete model of stability and develop protocols for optimizing catalyst performance.

20.
Eur J Radiol Open ; 9: 100451, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36345320

RESUMO

Background: We conducted this study to assess the diagnostic test properties of point of care ultrasonography (POCUS) of lung and cardiovascular system in prediction of mortality in COVID-19 patients. Methods: This is a cross-sectional study of 178 Covid-19 patients; POCUS was performed within one hour of admission to the ICU. We estimated sensitivity, specificity, positive predictive value, negative predictive value for prediction of mortality. Results: The mean (SD) age of these patients was 57.3 (12.8) years. The findings were on cardiac ultrasonography were: mild pericardial effusion (45%), chamber dilatation (15%), hypokinesia (11%), and low ejection fraction (8%). In our study, 30 patients (17%) had died. A cut-off score of > to 13 (for lung ultrasound score [LUS]) had high sensitivity for mortality (93.3%, 95% CI: 77.9-99.2%). However, low ejection fraction (92.3%, 95% CI: 86,6-96.1%), and thrombosis in either vein (96.5%, 95% CI: 92.0-98.9%) were specific for mortality. A combination of LUS > =13 or low ejection fraction or thrombosis or spontaneous echo contrast (slow flow) improved sensitivity for mortality to 96.7% (95% CI: 82.8-99.9%). The agreement between LUS of > =13 and CT score of moderate/severe was 85.7% (95% CI: 62.8-100%). The interrater agreement between these two parameters was 0.82 (95% CI: 0.68, 0.97). Conclusions: Multi-organ POCUS is effective in diagnosis, prognosis, and management of COVID-19 patients. Rather than just lung ultrasound, clinicians should use multiorgan POCUS for early identification of severe lung involvement and thrombotic changes; it may help reduce mortality in these patients.

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