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1.
Sensors (Basel) ; 24(19)2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39409213

RESUMO

Metal oxide core-shell fibrous nanostructures are promising gas-sensitive materials for the detection of a wide variety of both reducing and oxidizing gases. In these structures, two dissimilar materials with different work functions are brought into contact to form a coaxial heterojunction. The influence of the shell material on the transportation of the electric charge carriers along these structures is still not very well understood. This is due to homo-, hetero- and metal/semiconductor junctions, which make it difficult to investigate the electric charge transfer using direct current methods. However, in order to improve the gas-sensing properties of these complex structures, it is necessary to first establish a good understanding of the electric charge transfer in ambient air. In this article, we present an impedance spectroscopy study of networked SnO2/Ga2O3 core-shell nanobelts in ambient air. Tin dioxide nanobelts were grown directly on interdigitated gold electrodes, using the thermal sublimation method, via the vapor-liquid-solid (VLS) mechanism. Two forms of a gallium oxide shell of varying thickness were prepared via halide vapor-phase epitaxy (HVPE), and the impedance spectra were measured at 189-768 °C. The bulk resistance of the core-shell nanobelts was found to be reduced due to the formation of an electron accumulation layer in the SnO2 core. At temperatures above 530 °C, the thermal reduction of SnO2 and the associated decrease in its work function caused electrons to flow from the accumulation layer into the Ga2O3 shell, which resulted in an increase in bulk resistance. The junction resistance of said core-shell nanostructures was comparable to that of SnO2 nanobelts, as both structures are likely connected through existing SnO2/SnO2 homojunctions comprising thin amorphous layers.

2.
Biomedicines ; 12(9)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39335497

RESUMO

Coronary artery aneurysm or ectasia (CAAE) is a term that includes both coronary artery ectasia (CAE) and coronary artery aneurysm (CAA), despite distinct phenotypes and definitions. This anomaly can be found in 0.15-5.3% of coronary angiography. CAE is a diffuse dilatation of the coronary artery at least 1.5 times wider than the diameter of the normal coronary artery in a patient with a length of over 20 mm or greater than one-third of the vessel. CAE can be further subdivided into diffuse and focal dilations by the number and the length of the dilated vessels. Histologically, it presents with extensive destruction of musculoelastic elements, marked degradation of collagen and elastic fibers, and disruption of the elastic lamina. Conversely, CAA is a focal lesion manifesting as focal dilatation, which can be fusiform (if the longitudinal diameter is greater than the transverse) or saccular (if the longitudinal diameter is smaller than the transverse). Giant CAA is defined as a 4-fold enlargement of the vessel diameter and is observed in only 0.02% of patients after coronary. An aneurysmal lesion can be either single or multiple. It can be either a congenital or acquired phenomenon. The pathophysiological mechanisms responsible for the formation of CAAE are not well understood. Atherosclerosis is the most common etiology of CAAE in adults, while Kawasaki disease is the most common in children. Other etiological factors include systemic connective tissue diseases, infectious diseases, vasculitis, congenital anomalies, genetic factors, and idiopathic CAA. Invasive assessment of CAAE is based on coronary angiography. Coronary computed tomography (CT) is a noninvasive method that enables accurate evaluation of aneurysm size and location. The most common complications are coronary spasm, local thrombosis, distal embolization, coronary artery rupture, and compression of adjacent structures by giant coronary aneurysms. The approach to each patient with CAAE should depend on the severity of symptoms, anatomical structure, size, and location of the aneurysm. Treatment methods should be carefully considered to avoid possible complications of CAAE. Simultaneously, we should not unnecessarily expose the patient to the risk of intervention or surgical treatment. Patients can be offered conservative or invasive treatment. However, there are still numerous controversies and ambiguities regarding the etiology, prognosis, and treatment of patients with coronary artery aneurysms. This study summarizes the current knowledge about this disease's etiology, pathogenesis, and management.

3.
Sensors (Basel) ; 24(17)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39275601

RESUMO

The detection of dimethyl sulphide (DMS) at levels between ppb and ppm is a significant area of research due to the necessity of monitoring the presence of this gas in a variety of environments. These include environmental protection, industrial safety and medical diagnostics. Issues related to certain uncertainties concerning the influence of high humidity on DMS measurements with resistive gas sensors, e.g., in the detection of this marker in exhaled air, of the still unsatisfactory lower detection limit of DMS are the subject of intensive research. This paper presents the results of modifying the composition of the ZnO-based sensor layer to develop a DMS sensor with higher sensitivity and lower detection limit (LOD). Improved performance was achieved by using ZnO in the form of hexagonal nano- and microplates doped with gold nanoparticles (0.75 wt.%) and by using a well-proven sepiolite-based passive filter. The modification of the layer composition with respect to the authors' previous studies contributed to the development of a sensor that is highly sensitive to 1 ppm DMS (S = 11.4) and achieves an LOD of up to 406 ppb, despite the presence of a high water vapour content (90% RH) in the analysed atmosphere.

4.
Int J Cardiol ; 415: 132436, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39153511

RESUMO

INTRODUCTION: Percutaneous coronary intervention (PCI) with drug-eluting stents (DES) in complex coronary artery disease (CAD) has been established as the standard of care, but stent-related events are not uncommon. Sirolimus-Coated Balloon (SCB)-based angioplasty is an emerging technology, although it needs to be thoroughly evaluated compared with DES in the complex PCI setting. This study aimed to investigate the safety and efficacy of SCB-based angioplasty compared with new-generation DES in complex PCI. METHODS: Net adverse cardiovascular events (NACE: all-cause death, target lesion revascularization, non-fatal myocardial infarction, and major bleedings according to BARC classification), as a primary study endpoint was compared between SCB and new-generation DES for complex coronary lesions. RESULTS: Among 1782 patients with complex CAD, 1076 were treated with a sirolimus-coated balloon (EASTBOURNE Registry) and 706 with new-generation DES (COMPLEX Registry). After propensity score matching, a total of 512 patients in both groups were analyzed. NACE occurred more significantly in the DES group during the 1-year follow-up (10.5% vs. 3.9%, p = 0.003), mainly due to a higher risk of bleeding (6.6% vs. 0.4%, p = 0.001). The Cox model adjusted for lesion length showed a significantly lower hazard of NACE (HR: 0.23, CI [0.10, 0.52], p < 0.001) and all-cause mortality (HR: 0.07, CI [0.01, 0.66], p = 0.020) in SCB compared to DES group. CONCLUSIONS: SCB angioplasty has an advantage over DES for the treatment of complex CAD regarding NACE, significantly reducing the incidence of major bleeding without increasing ischemic endpoints. SCB may be an alternative to DES in selected patients with complex coronary lesions.


Assuntos
Angioplastia Coronária com Balão , Doença da Artéria Coronariana , Stents Farmacológicos , Pontuação de Propensão , Sirolimo , Humanos , Sirolimo/administração & dosagem , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Doença da Artéria Coronariana/cirurgia , Doença da Artéria Coronariana/terapia , Doença da Artéria Coronariana/diagnóstico por imagem , Angioplastia Coronária com Balão/métodos , Angioplastia Coronária com Balão/instrumentação , Angioplastia Coronária com Balão/efeitos adversos , Sistema de Registros , Seguimentos , Resultado do Tratamento , Materiais Revestidos Biocompatíveis
7.
Sensors (Basel) ; 24(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38475240

RESUMO

Frequency-selective surfaces (FSS) are two-dimensional geometric structures made of conductive materials that selectively transmit or reflect electromagnetic waves. In this paper, flexible FSS made on textile and film substrates is presented and compared to show the effect of the texture associated with the type of substrate on the shielding properties. Three geometries of patterns of squares in the border, inversion of squares in the border, and circles with a border were used, and the patterns were made by the silver paste screen printing technique. Microscopic analysis (SEM and optical) was performed to determine the degree of substrate coverage and the actual geometry of the pattern. The resistance per square of the obtained patterns was about 50 mΩ/□. The shielding properties of FSS were simulated in Comsol Multiphysics 6.2 software and then measured by the antenna method. Selective textile filters were obtained, depending on the pattern used, with one or two modals with a transmission attenuation of about 15 dB. The paper analyzes the effect of the substrate and the screen printing technique used on the shielding properties of the flexible FSS.

10.
J Clin Med ; 12(20)2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37892644

RESUMO

Lymphomas are a group of malignant tumors that originate in the lymphatic system. It is the most common type of blood cancer. It affects the lymph nodes, spleen, bone marrow, blood, and other organs. They can be aggressive or chronic. Hodgkin lymphoma survival rate is 2 in 100,000 people. Young adults aged 20-30 and people over 50 are most often affected. The prognosis of Hodgkin's lymphoma is good, with a survival rate of up to 80 percent. Nevertheless, in 20-30 percent of patients who initially respond to treatment, the disease has a tendency to progress. The positive effect of radiotherapy (RT) on patients' survival rates has been proven in many randomized clinical trials. Although the dose of chest RT has significantly reduced over the years, we still struggle with the long-term complications of post-RT repercussions, mainly because there is no established safe dose of RT affecting the heart. Other complications include earlier onset of coronary artery disease, early and late onset of pericarditis, valve degeneration (predominantly of the left heart), calcification of the aorta and its branches, heart failure, and arrhythmias. One patient can manifest each of the abovementioned complications, as in the present case. That is why choosing the right treatment strategy is crucial.

11.
Pharmaceuticals (Basel) ; 16(9)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37765060

RESUMO

Pulmonary hypertension (PH) is a severe vascular complication of connective tissue diseases (CTD). Patients with CTD may develop PH belonging to diverse groups: (1) pulmonary arterial hypertension (PAH), (2) PH due to left heart disease, (3) secondary PH due to lung disease and/or hypoxia and (4) chronic thromboembolic pulmonary hypertension (CTEPH). PAH most often develops in systemic scleroderma (SSc), mostly in its limited variant. PAH-CTD is a progressive disease characterized by poor prognosis. Therefore, early diagnosis should be established. A specific treatment for PAH-CTD is currently available and recommended: prostacyclin derivative (treprostinil, epoprostenol, iloprost, selexipag), nitric oxide and natriuretic pathway: stimulators of soluble guanylate cyclase (sGC: riociguat) and phosphodiesterase-five inhibitors (PDE5i: sildenafil, tadalafil), endothelin receptor antagonists (ERA: bosentan, macitentan, ambrisentan). Moreover, novel drugs, e.g., sotatercept, have been intensively investigated in clinical trials. We aim to review the literature on recent advances in the treatment strategy and prognosis of patients with PAH-CTD. In this manuscript, we discuss the mechanism of action of PAH-specific drugs and new agents and the latest research conducted on PAH-CTD patients.

12.
J Pers Med ; 13(6)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37373885

RESUMO

Cardiological and oncological patients comprise the majority of patients admitted to the emergency unit with chronic or acute conditions that are the dominant cause of death worldwide. However, electrotherapy and implantable devices (pacemakers and cardioverters) improve the prognosis of cardiological patients. We present the case report of a patient who, in the past, had a pacemaker implanted due to symptomatic sick sinus syndrome (SSS) without removing the two remaining leads. Echocardiography revealed severe tricuspid valve regurgitation. The tricuspid valve septal cusp was in a restricting position due to the two ventricular leads passing through the valve. A few years later, she was diagnosed with breast cancer. We present a 65-year-old female admitted to the department due to right ventricular failure. The patient manifested symptoms of right heart failure, predominated by ascites and lower extremity edema, despite increasing doses of diuretics. The patient underwent a mastectomy two years ago due to breast cancer and was qualified for thorax radiotherapy. A new pacemaker system was implanted in the right subclavian area as the pacemaker generator occupied the radiotherapy field. In the case of right ventricular lead removal and the need for pacing and resynchronization therapy, guidelines allow a coronary sinus for LV pacing to avoid passing the leads through the tricuspid valve. We facilitated this approach in our patient, suggesting that the percentage of ventricular pacing was very low.

13.
J Clin Med ; 12(11)2023 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-37298033

RESUMO

Although the treatment and prognosis of patients after heart transplantation have significantly improved, late graft dysfunction remains a critical problem. Two main subtypes of late graft dysfunction are currently described: acute allograft rejection and cardiac allograft vasculopathy, and microvascular dysfunction appears to be the first stage of both. Studies revealed that coronary microcirculation dysfunction, assessed by invasive methods in the early post-transplant period, correlates with a higher risk of late graft dysfunction and death during long-term follow-up. The index of microcirculatory resistance, measured early after heart transplantation, might identify the patients at higher risk of acute cellular rejection and major adverse cardiovascular events. It may also allow optimization and enhancement of post-transplantation management. Moreover, cardiac allograft vasculopathy is an independent prognostic factor for transplant rejection and survival rate. The studies showed that the index of microcirculatory resistance correlates with anatomic changes and reflects the deteriorating physiology of the epicardial arteries. In conclusion, invasive assessment of the coronary microcirculation, including the measurement of the microcirculatory resistance index, is a promising approach to predict graft dysfunction, especially the acute allograft rejection subtype, during the first year after heart transplantation. However, further advanced studies are needed to fully grasp the importance of microcirculatory dysfunction in patients after heart transplantation.

15.
J Pers Med ; 13(5)2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-37241008

RESUMO

Transcatheter aortic valve implantation (TAVI) is currently becoming the method of choice in high-risk patients with severe aortic valve stenosis. Post-TAVI complications are more common owing to the increasing use of the method. The majority of TAVI complications derive from concomitant aortic stenosis with moderate/severe aortic insufficiency, paravalvular leak, and atrioventricular block. The contemporary TAVI qualification process includes a thorough echocardiography and angio-CT of the aorta, which is crucial in assessing valve measurements, determining the position of the coronary arteries branching from the aorta, and choosing the optimal valve size. We present the case report of an 81-year-old patient admitted to our hospital because of exacerbation of the clinical condition and development of pulmonary edema a few days after TAVI. Despite the reduction of the initial leak, an echocardiographic examination revealed the remaining severe paravalvular aortic leakage. We performed open-heart cardio-thoracic surgery, explanted the TAVI valve, and implanted the biological prosthesis (Edwards Perimount Magna size 25). Introduction of new interventional treatment approaches and the availability of imaging tools have substantially reduced the incidence of significant paravalvular leak and offered a better prognosis for patients undergoing TAVI.

16.
Int J Mol Sci ; 24(6)2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36982889

RESUMO

MicroRNAs (miRNAs) are currently investigated as crucial regulatory factors which may serve as a potential therapeutic target. Reports on the role of miRNA in patients with coronary artery aneurysmal disease (CAAD) are limited. The present analysis aims to confirm the differences in the expression of previously preselected miRNAs in larger study groups and evaluate their usefulness as potential markers of CAAD. The study cohort included 35 consecutive patients with CAAD (Group 1), and two groups of 35 patients matched Group 1 regarding sex and age from the overall cohort of 250 patients (Group 2 and Group 3). Group 2 included patients with angiographically documented coronary artery disease (CAD), while Group 3 enrolled patients with normal coronary arteries (NCA) assessed during coronary angiography. We applied the RT-qPCR method using the custom plates for the RT-qPCR array. We confirmed that the level of five preselected circulating miRNAs was different in patients with CAAD compared to Group 2 and Group 3. We found that miR-451a and miR-328 significantly improved the CAAD prediction. In conclusion, miR-451a is a significant marker of CAAD compared to patients with CAD. In turn, miR-328-3p is a significant marker of CAAD compared to patients with NCA.


Assuntos
MicroRNA Circulante , Doença da Artéria Coronariana , MicroRNAs , Humanos , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/genética , MicroRNA Circulante/genética , MicroRNAs/genética , Angiografia Coronária , Biomarcadores
17.
J Clin Med ; 12(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36902751

RESUMO

The authors present a new paper examining the disturbances in ocular circulation and electrophysiological changes in the presence of neuro-ophthalmic manifestations in a patient with cerebral autosomal dominant arteriopathy with subcortical infracts and leucoencephalopathy (CADASIL). Symptoms reported by the patient included: transient vision loss (TVL), migraines, diplopia, bilateral peripheral visual field loss and convergence insufficiency. CADASIL was confirmed by the presence of NOTCH3 gene mutation (p.Cys212Gly), the presence of granular osmiophilic material (GOM) in cutaneous vessels in an immunohistochemistry test (IHC) and bilateral focal vasogenic lesions in the white matter of the cerebral hemisphere, with micro-focal infarct in the left external capsule on a magnetic resonance imaging test (MRI). Color Doppler imaging (CDI) confirmed decreased blood flow and increased vascular resistance in the retinal and posterior ciliary arteries, with reduced P50 wave amplitude on a pattern electroretinogram (PERG). An eye fundus examination and fluorescein angiography (FA) revealed the constriction of retinal vessels and a peripheral retinal pigment epithelium (RPE) atrophy with focal drusen. The authors suggest that the cause of TVL may be changes in the hemodynamics of the retinochoroid vessels associated with the narrowing of small vessels and the presence of druses in the retina-which is supported by a decrease in the amplitude of the P50 wave in PERG, changes in OCT correlating simultaneously with changes in MRI imaging and other neurological symptoms.

19.
High Blood Press Cardiovasc Prev ; 30(1): 29-36, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36396904

RESUMO

INTRODUCTION: 2018 ESC/ESH guidelines have recommended 24-h ambulatory blood pressure monitoring to assess hypotensive therapy in many circumstances. Recommended target blood pressure in office blood pressure measurements is between 120/70 and 130/80 mmHg. Such targets for 24-h ambulatory blood pressure monitoring lacks. AIM: We aimed to define target values of blood pressure in 24-h ambulatory blood pressure monitoring in hypertensive patients. METHODS: Office blood pressure measurements and 24-h ambulatory blood pressure monitoring data were collected from 1313 hypertensive patients and sorted following increasing systolic (SBP)/diastolic (DBP) blood pressure in office blood pressure measurements. The corresponding 24-h ambulatory blood pressure monitoring to office blood pressure measurements values were calculated. RESULTS: Values 130/80 mmHg in office blood pressure measurements correspond in 24-h ambulatory blood pressure monitoring: night-time SBP/DBP mean: 113.74/66.95 mmHg; daytime SBP/DBP mean: 135.02/81.78 mmHg and 24-h SBP/DBP mean: 130.24/78.73 mmHg. Values 120/70 mmHg in office blood pressure measurements correspond in 24-h ambulatory blood pressure monitoring: night-time SBP/DBP mean: 109.50/63.43 mmHg; daytime SBP/DBP mean: 131.01/78.47 mmHg and 24-h SBP/DBP mean: 126.36/75.31 mmHg. CONCLUSIONS: The proposed blood pressure target values in 24-h ambulatory blood pressure monitoring complement the therapeutic target indicated in the ESC/ESH recommendations and improves 24-h ambulatory blood pressure monitoring usefulness in clinical practice.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Hipertensão , Humanos , Pressão Sanguínea , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Determinação da Pressão Arterial
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