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1.
Vascul Pharmacol ; : 107379, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38762131

RESUMO

Pulmonary hypertension (PH) is a progressive, severe and to date not curable disease of the pulmonary vasculature. Alterations of the insulin-like growth factor 1 (IGF-1) system are known to play a role in vascular pathologies and IGF-binding proteins (IGFBPs) are important regulators of the bioavailability and function of IGFs. In this study, we show that circulating plasma levels of IGFBP-1, IGFBP-2 and IGFBP-3 are increased in idiopathic pulmonary arterial hypertension (IPAH) patients compared to healthy individuals. These binding proteins inhibit the IGF-1 induced IGF-1 receptor (IGF1R) phosphorylation and exhibit diverging effects on the IGF-1 induced signaling pathways in human pulmonary arterial cells (i.e. healthy as well as IPAH-hPASMCs, and healthy hPAECs). Furthermore, IGFBPs are differentially expressed in an experimental mouse model of PH. In hypoxic mouse lungs, IGFBP-1 mRNA expression is decreased whereas the mRNA for IGFBP-2 is increased. In contrast to IGFBP-1, IGFBP-2 shows vaso-constrictive properties in the murine pulmonary vasculature. Our analyses show that IGFBP-1 and IGFBP-2 exhibit diverging effects on IGF-1 signaling and display a unique IGF1R-independent kinase activation pattern in human pulmonary arterial smooth muscle cells (hPASMCs), which represent a major contributor of PAH pathobiology. Furthermore, we could show that IGFBP-2, in contrast to IGFBP-1, induces epidermal growth factor receptor (EGFR) signaling, Stat-3 activation and expression of Stat-3 target genes. Based on our results, we conclude that the IGFBP family, especially IGFBP-1, IGFBP-2 and IGFBP-3, are deregulated in PAH, that they affect IGF signaling and thereby regulate the cellular phenotype in PH.

2.
Micromachines (Basel) ; 15(3)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38542642

RESUMO

The three-point bending test is a valuable method for evaluating the mechanical properties of 3D-printed biomaterials, which can be used in various applications. The use of 3D printing in specimen preparation enables precise control over material composition and microstructure, facilitating the investigation of different printing parameters and advanced materials. The traditional approach to analyzing the mechanical properties of a material using a three-point bending test has the disadvantage that it provides only global information about the material's behavior. This means that it does not provide detailed insight into the local strain distribution within the material. However, the 2D Digital Image Correlation (DIC) method offers additional insight, especially in terms of strain localization. DIC is an optical technique that measures full-field displacements and strains on the surface of a sample. PLA and enhanced PLA-X material were utilized to create three-point bending samples. The aim of this paper was to analyze and compare the influence of aging on the mechanical properties of PLA and enhanced PLA-X materials using three-point bending coupled with the DIC method. The results showed statistically significant differences between the PLA and PLA-X, for both the new and aged materials. The aged PLA samples had the highest average value of maximal force around 68 N, which was an increase of 8.8% compared to the new PLA samples. On the other hand, the aged PLA-X material had an increase of 7.7% in the average maximal force compared to the new PLA-X samples. When comparing the two materials, the PLA samples had higher maximal force values, 6.2% for the new samples, and 7.3% for the aged samples. The DIC results showed that both the new PLA and PLA-X samples endured higher strain values at Points 1 and 2 than the aged ones, except for the aged PLA-X sample at Point 2, where the new sample had higher strain values. However, for the first 5 min of the experiment, both materials exhibited identical behavior, after which point significant differences started to occur for both materials, as well as at Points 1 and 2. A more profound comprehension of the biomechanical characteristics of both PLA and PLA-X material is essential to enhance the knowledge for potential biomedical applications. The DIC method was found to be a powerful tool for analyzing the deformation and failure behavior of samples and for complementing the traditional approach to material testing.

3.
PeerJ Comput Sci ; 10: e1795, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38259888

RESUMO

Renewable energy plays an increasingly important role in our future. As fossil fuels become more difficult to extract and effectively process, renewables offer a solution to the ever-increasing energy demands of the world. However, the shift toward renewable energy is not without challenges. While fossil fuels offer a more reliable means of energy storage that can be converted into usable energy, renewables are more dependent on external factors used for generation. Efficient storage of renewables is more difficult often relying on batteries that have a limited number of charge cycles. A robust and efficient system for forecasting power generation from renewable sources can help alleviate some of the difficulties associated with the transition toward renewable energy. Therefore, this study proposes an attention-based recurrent neural network approach for forecasting power generated from renewable sources. To help networks make more accurate forecasts, decomposition techniques utilized applied the time series, and a modified metaheuristic is introduced to optimized hyperparameter values of the utilized networks. This approach has been tested on two real-world renewable energy datasets covering both solar and wind farms. The models generated by the introduced metaheuristics were compared with those produced by other state-of-the-art optimizers in terms of standard regression metrics and statistical analysis. Finally, the best-performing model was interpreted using SHapley Additive exPlanations.

4.
Sensors (Basel) ; 23(24)2023 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-38139724

RESUMO

Monitoring heart electrical activity is an effective way of detecting existing and developing conditions. This is usually performed as a non-invasive test using a network of up to 12 sensors (electrodes) on the chest and limbs to create an electrocardiogram (ECG). By visually observing these readings, experienced professionals can make accurate diagnoses and, if needed, request further testing. However, the training and experience needed to make accurate diagnoses are significant. This work explores the potential of recurrent neural networks for anomaly detection in ECG readings. Furthermore, to attain the best possible performance for these networks, training parameters, and network architectures are optimized using a modified version of the well-established particle swarm optimization algorithm. The performance of the optimized models is compared to models created by other contemporary optimizers, and the results show significant potential for real-world applications. Further analyses are carried out on the best-performing models to determine feature importance.


Assuntos
Algoritmos , Redes Neurais de Computação , Eletrocardiografia/métodos
5.
Emerg Infect Dis ; 29(4): 843-845, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36958036

RESUMO

Thelazia callipaeda is a zoonotic vector-borne nematode that infects and causes eye disease among a wide range of domestic and wild mammals, including humans. We describe an unusual case of reinfection by this nematode in Serbia and call for a focus on preventive measures in endemic areas.


Assuntos
Doenças do Cão , Oftalmopatias , Infecções por Spirurida , Thelazioidea , Animais , Humanos , Cães , Reinfecção , Infecções por Spirurida/epidemiologia , Infecções por Spirurida/prevenção & controle , Infecções por Spirurida/veterinária , Sérvia , Doenças do Cão/epidemiologia , Mamíferos
6.
Medicina (Kaunas) ; 59(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36984490

RESUMO

Background and objectives: In patients with colorectal cancer (CRC), heterogeneous expression of Mismatch repair (MMR) proteins can manifest itself in several different forms and is not such a rare phenomenon. Therefore, it is very important to recognize the nuclear expression of MMR proteins of different MMR status in order to avoid false positive or false negative results. The aim of this study was to determine the frequency and distribution of heterogeneous expression of MMR proteins in patients with stages II and III of the disease as well as its association with clinical, demographic and pathological characteristics of CRC in relation to proficient and deficient expression of MMR proteins. Material and Methods: The study included 104 cases of colorectal cancer obtained from surgical colectomy material in stages II and III of the disease. Results: From a total of 104 patients with colorectal cancer, immunohistochemical analysis of the expression of all four MMR proteins showed that heterogeneous expression of MMR proteins (as well as deficient immunoreactivity of tumor cells) was present in 12 cases, while proficient expression of MMR proteins was detected in 80 tumors. Conclusions: Our study showed that the only independent predictors of the loss of MMR protein expression were younger patient age and right-sided anatomical location of the tumor. The study also established the existence of heterogeneous expression of MMR proteins in a non-negligible percentage of CRCs (11.5%), where heterogeneous nuclear expression of MMR proteins was described in several different forms.


Assuntos
Neoplasias Colorretais , Humanos , Neoplasias Colorretais/patologia , Estadiamento de Neoplasias , Proteínas Adaptadoras de Transdução de Sinal , Proteína 1 Homóloga a MutL/metabolismo
7.
Cells Tissues Organs ; 212(3): 203-214, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35605590

RESUMO

This study aimed to morphometrically examine the development of glomeruli and tubules in the kidney cortex of human foetuses at different gestational ages (GAs). We also investigated the expression of the proliferation marker Ki-67 and apoptosis-related markers Bcl-2 and Bax during nephrogenesis using immunohistochemistry. Kidney samples from 38 human foetuses of both sexes with GA ranging from 13 to 40 weeks were analysed. The samples were divided into 7 groups based on GA, each corresponding to 1 lunar month. Foetal kidneys showed a spatiotemporal gradient of nephron differentiation with the transient stages of nephron anlage located in the nephrogenic zone and immature nephrons located in the subjacent maturation zone. In the inner cortex, nephrons establish the morphological characteristics of definitive nephrons. The average area, perimeter, and Feret's diameter of the glomeruli formed within the kidney cortex gradually decreased up to a period of 29-32 weeks of gestation and subsequently increased until a period of 37-40 weeks. There was a weak negative correlation with GA. In contrast, the areal density of glomeruli increased up to a period of 21-24 weeks and then gradually decreased until a period of 37-40 weeks, showing a moderate negative correlation with GA. The average area of renal tubules slightly decreased until a period of 21-24 weeks of gestation and then gradually increased until a period of 36-40 weeks, showing a moderate positive correlation with GA. The average areal density of renal tubules increased significantly until a period of 21-24 weeks of gestation, remained relatively constant until a period of 33-36 weeks, and then increased significantly at 36-40 weeks. There was a strong positive correlation with GA. Our results showed that Ki-67 was expressed in numerous cells of the metanephric mesenchyme, pretubular aggregates, renal vesicles, comma-shaped bodies, and early S-shaped bodies. During subsequent development and the spatial expansion of nephrons towards the mature zone, the expression of Ki-67 was markedly reduced. Similarly, Bcl-2 was strongly expressed in induced nephrogenic progenitor cells, pretubular aggregates, renal vesicles, and comma-shaped bodies. As vascularisation and maturation of the nephron proceeded, Bcl-2 staining became less intense and limited to the parietal layer of the Bowman's capsule and renal tubules. Weak Bax expression was observed in individual scattered cells within segments of the nephrons at all developmental stages. In the mature zone, more intense Bax staining was observed in the renal tubules.


Assuntos
Nefropatias , Rim , Masculino , Feminino , Humanos , Proteína X Associada a bcl-2/metabolismo , Antígeno Ki-67/metabolismo , Néfrons , Glomérulos Renais , Nefropatias/metabolismo , Feto , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
8.
Cells ; 11(19)2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36230894

RESUMO

The role of microparticles (MPs) and cold in high altitude pulmonary hypertension (HAPH) remains unexplored. We investigated the impact of long-term cold exposure on the pulmonary circulation in lowlanders and high-altitude natives and the role of MPs. Pulmonary hemodynamics were evaluated using Doppler echocardiography at the end of the colder and warmer seasons. We further examined the miRNA content of MPs isolated from the study participants and studied their effects on human pulmonary artery smooth muscle (hPASMCs) and endothelial cells (hPAECs). Long-term exposure to cold environment was associated with an enhanced pulmonary artery pressure in highlanders. Plasma levels of CD62E-positive and CD68-positive MPs increased in response to cold in lowlanders and HAPH highlanders. The miRNA-210 expression contained in MPs differentially changed in response to cold in lowlanders and highlanders. MPs isolated from lowlanders and highlanders increased proliferation and reduced apoptosis of hPASMCs. Further, MPs isolated from warm-exposed HAPH highlanders and cold-exposed highlanders exerted the most pronounced effects on VEGF expression in hPAECs. We demonstrated that prolonged exposure to cold is associated with elevated pulmonary artery pressures, which are most pronounced in high-altitude residents. Further, the numbers of circulating MPs are differentially increased in lowlanders and HAPH highlanders during the colder season.


Assuntos
Hipertensão Pulmonar , MicroRNAs , Altitude , Doença da Altitude , Células Endoteliais , Humanos , Estações do Ano , Fator A de Crescimento do Endotélio Vascular
9.
JACC Basic Transl Sci ; 7(7): 658-677, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35958691

RESUMO

We sought to unravel pathomechanisms of the transition of maladaptive right ventricular (RV) remodeling to right heart failure (RHF) upon pressure overload. Exposure of C57BL/6J and C57BL/6N mice to pulmonary artery banding disclosed a tight relation of structural remodeling with afterload, but a dissociation from RV systolic function. Reduced release of mitochondrial reactive oxygen species in C57BL/6J mice prevented the development of RHF. In patients with left heart failure, increased oxidative damage in RV sections was associated with severely impaired RV function. In conclusion, reactive oxygen species are involved in the transition of maladaptive RV remodeling to RHF.

10.
Sensors (Basel) ; 22(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35270856

RESUMO

We live in a period when smart devices gather a large amount of data from a variety of sensors and it is often the case that decisions are taken based on them in a more or less autonomous manner. Still, many of the inputs do not prove to be essential in the decision-making process; hence, it is of utmost importance to find the means of eliminating the noise and concentrating on the most influential attributes. In this sense, we put forward a method based on the swarm intelligence paradigm for extracting the most important features from several datasets. The thematic of this paper is a novel implementation of an algorithm from the swarm intelligence branch of the machine learning domain for improving feature selection. The combination of machine learning with the metaheuristic approaches has recently created a new branch of artificial intelligence called learnheuristics. This approach benefits both from the capability of feature selection to find the solutions that most impact on accuracy and performance, as well as the well known characteristic of swarm intelligence algorithms to efficiently comb through a large search space of solutions. The latter is used as a wrapper method in feature selection and the improvements are significant. In this paper, a modified version of the salp swarm algorithm for feature selection is proposed. This solution is verified by 21 datasets with the classification model of K-nearest neighborhoods. Furthermore, the performance of the algorithm is compared to the best algorithms with the same test setup resulting in better number of features and classification accuracy for the proposed solution. Therefore, the proposed method tackles feature selection and demonstrates its success with many benchmark datasets.


Assuntos
Algoritmos , Inteligência Artificial , Aprendizado de Máquina
11.
Circulation ; 145(12): 916-933, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35175782

RESUMO

BACKGROUND: Pulmonary hypertension (PH) is a life-threatening disease, characterized by excessive pulmonary vascular remodeling, leading to elevated pulmonary arterial pressure and right heart hypertrophy. PH can be caused by chronic hypoxia, leading to hyper-proliferation of pulmonary arterial smooth muscle cells (PASMCs) and apoptosis-resistant pulmonary microvascular endothelial cells (PMVECs). On reexposure to normoxia, chronic hypoxia-induced PH in mice is reversible. In this study, the authors aim to identify novel candidate genes involved in pulmonary vascular remodeling specifically in the pulmonary vasculature. METHODS: After microarray analysis, the authors assessed the role of SPARC (secreted protein acidic and rich in cysteine) in PH using lung tissue from idiopathic pulmonary arterial hypertension (IPAH) patients, as well as from chronically hypoxic mice. In vitro studies were conducted in primary human PASMCs and PMVECs. In vivo function of SPARC was proven in chronic hypoxia-induced PH in mice by using an adeno-associated virus-mediated Sparc knockdown approach. RESULTS: C57BL/6J mice were exposed to normoxia, chronic hypoxia, or chronic hypoxia with subsequent reexposure to normoxia for different time points. Microarray analysis of the pulmonary vascular compartment after laser microdissection identified Sparc as one of the genes downregulated at all reoxygenation time points investigated. Intriguingly, SPARC was vice versa upregulated in lungs during development of hypoxia-induced PH in mice as well as in IPAH, although SPARC plasma levels were not elevated in PH. TGF-ß1 (transforming growth factor ß1) or HIF2A (hypoxia-inducible factor 2A) signaling pathways induced SPARC expression in human PASMCs. In loss of function studies, SPARC silencing enhanced apoptosis and reduced proliferation. In gain of function studies, elevated SPARC levels induced PASMCs, but not PMVECs, proliferation. Coculture and conditioned medium experiments revealed that PMVECs-secreted SPARC acts as a paracrine factor triggering PASMCs proliferation. Contrary to the authors' expectations, in vivo congenital Sparc knockout mice were not protected from hypoxia-induced PH, most probably because of counter-regulatory proproliferative signaling. However, adeno-associated virus-mediated Sparc knockdown in adult mice significantly improved hemodynamic and cardiac function in PH mice. CONCLUSIONS: This study provides evidence for the involvement of SPARC in the pathogenesis of human PH and chronic hypoxia-induced PH in mice, most likely by affecting vascular cell function.


Assuntos
Hipertensão Pulmonar , Animais , Proliferação de Células , Células Cultivadas , Células Endoteliais/metabolismo , Hipertensão Pulmonar Primária Familiar/metabolismo , Humanos , Hipertensão Pulmonar/patologia , Hipóxia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miócitos de Músculo Liso/metabolismo , Osteonectina/genética , Artéria Pulmonar , Remodelação Vascular/genética
12.
Int J Mol Sci ; 21(23)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33265921

RESUMO

Although the response of the right ventricle (RV) to the increased afterload is an important determinant of the patient outcome, very little is known about the underlying mechanisms. Mast cells have been implicated in the pathogenesis of left ventricular maladaptive remodeling and failure. However, the role of mast cells in RV remodeling remains unexplored. We subjected mast cell-deficient WBB6F1-KitW/W-v (KitW/KitW-v) mice and their mast cell-sufficient littermate controls (MC+/+) to pulmonary artery banding (PAB). PAB led to RV dilatation, extensive myocardial fibrosis, and RV dysfunction in MC+/+ mice. In PAB KitW/KitW-v mice, RV remodeling was characterized by minimal RV chamber dilatation and preserved RV function. We further administered to C57Bl/6J mice either placebo or cromolyn treatment starting from day 1 or 7 days after PAB surgery to test whether mast cells stabilizing drugs can prevent or reverse maladaptive RV remodeling. Both preventive and therapeutic cromolyn applications significantly attenuated RV dilatation and improved RV function. Our study establishes a previously undescribed role of mast cells in pressure overload-induced adverse RV remodeling. Mast cells may thus represent an interesting target for the development of a new therapeutic approach directed specifically at the heart.


Assuntos
Mastócitos/metabolismo , Mastócitos/patologia , Pressão , Remodelação Ventricular/genética , Animais , Biomarcadores/metabolismo , Cromolina Sódica/administração & dosagem , Cromolina Sódica/farmacologia , Fibrose , Regulação da Expressão Gênica/efeitos dos fármacos , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Hipertrofia , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Masculino , Mastócitos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Remodelação Ventricular/efeitos dos fármacos
13.
Medicina (Kaunas) ; 56(12)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302424

RESUMO

Background and objectives: Deficient mismatch repair (MMR) status is associated with good prognosis but poor therapeutic response to adjuvant chemotherapy in patients with colorectal cancer. However, there are some opposed arguments considering therapeutic outcomes in patients with evidenced MMR deficiency in colorectal cancer. The aim of the study was the investigation of prognostic value and immunohistochemical analysis of the MMR-deficiency tumors. Materials and Methods: The study enrolled 104 patients with resected stage II and III colorectal cancer samples from the period 2018-2019. Results: The tumors with deficient MMR status were significantly associated with age up to 50 years and right-sided localization (p < 0.001). During the follow-up period of 22.43 ± 6.66 months, 21 patients (20.2%) died, whereas 14 patients (13.5%) had relapses. The loss of mutL homologue 1/postmeiotic segregation increased 2 (MLH1/PMS2) expression, compared to proficient MMR tumors, was associated with shorter disease-free survival in patients with lymphovascular invasion (p < 0.05), perineural invasion (p < 0.01), stage III (p < 0.05) and high-grade tumor (p < 0.05). Conclusions: This retrospective pilot study of a single-center cohort of patients with stage II and III colorectal cancer highlights the clinical importance of using immunohistochemistry (IHC) analysis as a guide for diagnostic algorithm in a country with limited resources, but with a high prevalence of colorectal carcinoma in the young patients. MMR-deficiency tumors compared with proficient MMR colorectal cancer was not shown to be a significant predictor of disease-free and overall survival.


Assuntos
Neoplasias Colorretais , Recidiva Local de Neoplasia , Neoplasias Encefálicas , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Humanos , Proteína 1 Homóloga a MutL/genética , Estadiamento de Neoplasias , Síndromes Neoplásicas Hereditárias , Projetos Piloto , Prognóstico , Estudos Retrospectivos
14.
Pulm Circ ; 10(4): 2045894020947283, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33240483

RESUMO

Pulmonary arterial hypertension is a severe respiratory disease characterized by pulmonary artery remodeling. RV dysfunction and dysregulated circulating metabolomics are associated with adverse outcomes in pulmonary arterial hypertension. We investigated effects of tadalafil and macitentan alone or in combination on the RV and plasma metabolomics in SuHx and PAB models. For SuHx model, rats were injected with SU5416 and exposed to hypoxia for three weeks and then were returned to normoxia and treated with either tadalafil (10 mg/kg in chow) or macitentan (10 mg/kg in chow) or their combination (both 10 mg/kg in chow) for two weeks. For PAB model, rats were subjected to either sham or PAB surgery for three weeks and treated with above-mentioned drugs from week 1 to week 3. Following terminal echocardiographic and hemodynamic measurements, tissue samples were collected for metabolomic, histological and gene expression analysis. Both SuHx and PAB rats developed RV remodeling/dysfunction with severe and mild plasma metabolomic alterations, respectively. In SuHx rats, tadalafil and macitentan alone or in combination improved RV remodeling/function with the effects of macitentan and combination therapy being superior to tadalafil. All therapies similarly attenuated SuHx-induced changes in plasma metabolomics. In PAB rats, only macitentan improved RV remodeling/function, while only tadalafil attenuated PAB-induced changes in plasma metabolomics.

15.
Sci Adv ; 6(16): eaba0694, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32426457

RESUMO

Mitochondria play an important role in sensing both acute and chronic hypoxia in the pulmonary vasculature, but their primary oxygen-sensing mechanism and contribution to stabilization of the hypoxia-inducible factor (HIF) remains elusive. Alteration of the mitochondrial electron flux and increased superoxide release from complex III has been proposed as an essential trigger for hypoxic pulmonary vasoconstriction (HPV). We used mice expressing a tunicate alternative oxidase, AOX, which maintains electron flux when respiratory complexes III and/or IV are inhibited. Respiratory restoration by AOX prevented acute HPV and hypoxic responses of pulmonary arterial smooth muscle cells (PASMC), acute hypoxia-induced redox changes of NADH and cytochrome c, and superoxide production. In contrast, AOX did not affect the development of chronic hypoxia-induced pulmonary hypertension and HIF-1α stabilization. These results indicate that distal inhibition of the mitochondrial electron transport chain in PASMC is an essential initial step for acute but not chronic oxygen sensing.

16.
Medicina (Kaunas) ; 56(3)2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32188043

RESUMO

Background and objectives: Pulmonary hypertension (PH) is characterized by the vasoconstriction and abnormally proliferative vascular cells. The available allopathic treatment options for PH are still not able to cure the disease. Alternative medicine is becoming popular and drawing the attention of the general public and scientific communities. The entomogenous fungus Yarsagumba (Cordyceps sinensis) and its biologically active ingredient cordycepin may represent the therapeutic option for this incurable disease, owing to their anti-inflammatory, vasodilatory and anti-oxidative effects. Methods: In this study, we investigated whether Yarsagumba extract and cordycepin possess anti-proliferative and vasorelaxant properties in the context of PH, using 5-bromo-2'-deoxyuridine assay and isolated mice lungs, respectively. Results: Our results revealed that Yarsagumba extract and its bioactive compound cordycepin significantly attenuated the proliferation of human pulmonary artery smooth muscle cells derived from donor and PH subjects. In isolated murine lungs, only Yarsagumba extract, but not cordycepin, resulted in vasodilatation, indicating the probable existence of other bioactive metabolites present in Yarsagumba that may be responsible for this outcome. Conclusion: Future comprehensive in vivo and in vitro research is crucially needed to discover the profound mechanistic insights with regard to this promising therapeutic potency of Yarsagumba extract and to provide further evidence as to whether it can be used as a strategy for the treatment of PH.


Assuntos
Antifúngicos/farmacologia , Materiais Biocompatíveis/farmacologia , Desoxiadenosinas/farmacologia , Hipertensão Pulmonar/tratamento farmacológico , Vasodilatadores/farmacologia , Animais , Antifúngicos/administração & dosagem , Materiais Biocompatíveis/administração & dosagem , Estudos de Casos e Controles , Proliferação de Células/efeitos dos fármacos , Cordyceps/química , Cordyceps/metabolismo , Desoxiadenosinas/administração & dosagem , Humanos , Hipertensão Pulmonar/fisiopatologia , Pulmão/irrigação sanguínea , Pulmão/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Placebos/administração & dosagem , Vasodilatadores/administração & dosagem
17.
Cardiovasc Res ; 116(2): 406-415, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31020333

RESUMO

AIMS: In patients with pulmonary hypertension, right ventricular hypertrophy (RVH) is a detrimental condition that ultimately results in right heart failure and death. The ubiquitin proteasome system has been identified as a major protein degradation system to regulate cardiac remodelling in the left heart. Its role in right heart hypertrophy, however, is still ambiguous. METHODS AND RESULTS: RVH was induced in mice by pulmonary artery banding (PAB). Both, expression and activity of the proteasome was found to be up-regulated in the hypertrophied right ventricle (RV) compared to healthy controls. Catalytic inhibition of the proteasome by the two proteasome inhibitors Bortezomib (BTZ) and ONX-0912 partially improved RVH both in preventive and therapeutic applications. Native gel analysis revealed that specifically the 26S proteasome complexes were activated in experimental RVH. Increased assembly of 26S proteasomes was accompanied by elevated expression of Rpn6, a rate-limiting subunit of 26S proteasome assembly, in hypertrophied cardiomyocytes of the right heart. Intriguingly, patients with RVH also showed increased expression of Rpn6 in hypertrophied cardiomyocytes of the RV as identified by immunohistochemical staining. CONCLUSION: Our data demonstrate that alterations in expression and activity of proteasomal subunits play a critical role in the development of RVH. Moreover, this study provides an improved understanding on the selective activation of the 26S proteasome in RVH that might be driven by the rate-limiting subunit Rpn6. In RVH, Rpn6 therefore represents a more specific target to interfere with proteasome function than the commonly used catalytic proteasome inhibitors.


Assuntos
Ventrículos do Coração/enzimologia , Hipertrofia Ventricular Direita/enzimologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Função Ventricular Direita , Remodelação Ventricular , Animais , Modelos Animais de Doenças , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Direita/patologia , Hipertrofia Ventricular Direita/fisiopatologia , Hipertrofia Ventricular Direita/prevenção & controle , Mediadores da Inflamação/metabolismo , Camundongos , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Inibidores de Proteassoma/farmacologia , Transdução de Sinais , Ubiquitinação , Função Ventricular Direita/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
18.
Pulm Circ ; 9(4): 2045894019881954, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31819797

RESUMO

Pulmonary fibrosis is a progressive disease characterized by disruption of lung architecture and deregulation of the pulmonary function. Prostacyclin, a metabolite of arachidonic acid, is a potential disease mediator since it exerts anti-inflammatory and anti-fibrotic actions. We investigated the effect of treprostinil, a prostacyclin analogue, in bleomycin-induced experimental pulmonary fibrosis. Bleomycin sulfate or saline was administrated intratracheally to mice (n = 9-10/group) at day 0. Orotracheal aspiration of treprostinil or vehicle was administered daily and started 24 h prior to bleomycin challenge. Evaluation of lung pathology was performed in tissue samples and bronchoalveolar lavage fluid collected 7, 14 and 21 days after bleomycin exposure. Lung injury was achieved due to bleomycin exposure at all time points as indicated by impaired lung mechanics, pathologic lung architecture (from day 14), and cellular and protein accumulation in the alveolar space accompanied by a minor decrease in lung tissue VE-cadherin at day 14. Treprostinil preserved lung mechanics, and reduced lung inflammation, fibrosis, and vascular remodeling (day 21); reduced cellularity and protein content of bronchoalveolar lavage fluid were additionally observed with no significant effect on VE-cadherin expression. Bleomycin-induced collagen deposition was attenuated by treprostinil from day 14, while treprostinil involvement in regulating inflammatory processes appears mediated by NF-κB signaling. Overall, prophylactic administration of treprostinil, a stable prostacyclin analogue, maintained lung function, and prevented bleomycin-induced lung injury, and fibrosis, as well as vascular remodeling, a hallmark of pulmonary hypertension. This suggests potential therapeutic efficacy of treprostinil in pulmonary fibrosis and possibly in pulmonary hypertension related to chronic lung diseases.

19.
High Alt Med Biol ; 20(4): 375-382, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31464532

RESUMO

Background/Aims: Long-term high altitude residence leads to a sustained increase in pulmonary vascular resistance and elevation of pulmonary artery pressure due to chronic alveolar hypoxia. However, living at high altitude is also associated with other environmental factors such as cold. There is still little experimental evidence suggesting detrimental effects of low temperatures on the pulmonary vasculature. Therefore, our objective was to investigate acute effects of cold exposure on the pulmonary circulation in Kyrgyz high altitude natives. Methods: Responses of the pulmonary circulation during acute exposure to controlled cold conditions (4°C-6°C) for 60 minutes were measured in highlanders using Doppler echocardiography. Based on the Doppler echocardiography-derived tricuspid regurgitant systolic pressure gradient (TRG), subjects with TRG ≥40 mmHg were allocated into the pulmonary hypertension (PH) group. Participants from the PH group were compared with volunteer control subjects with TRG <40 mmHg. All baseline measurements were evaluated in a warm room during 60 minutes (22°C-28°C). Following baseline echocardiography, the subjects were assigned to either warm or cold exposure for an additional 60 minutes. Results: Acute cold exposure significantly increased TRG both in the control (ΔTRG, 4.93 mmHg) and in the PH (ΔTRG, 8.15 mmHg) group, compared to the respective warm exposure conditions (ΔTRG, -0.14 and -0.05 mmHg). No changes in cardiac output were observed upon cold exposure. Conclusion: Thus, acute exposure to cold leads to elevation of pulmonary artery pressure in high altitude residents.


Assuntos
Aclimatação/fisiologia , Doença da Altitude/fisiopatologia , Temperatura Baixa/efeitos adversos , Exposição Ambiental/efeitos adversos , Circulação Pulmonar/fisiologia , Adulto , Altitude , Ecocardiografia Doppler , Feminino , Humanos , Quirguistão , Masculino , Pessoa de Meia-Idade , Resistência Vascular
20.
Medicina (Kaunas) ; 55(8)2019 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-31405154

RESUMO

The currently used immunohistochemical approach in determining the estrogen receptor (ER) positivity of breast cancers (BCs) is inherently subjective and additionally limited by its semi-quantitative nature. The application of software in the analysis of digitized slide images may overcome some of these limitations. However, the utilization of such an approach requires that the entire staining procedure is standardized. BACKGROUND AND OBJECTIVES: We aimed to establish a procedure for the photometric and morphometric analysis of BC immunohistochemical parameters that can possibly be used for a diagnostic purpose that is in line with the current semi-quantitative scoring system. MATERIALS AND METHODS: Semi-quantitative analysis of ER-stained tissue sections was performed following the Allred scoring system guidelines. The quantitative analysis was performed in ImageJ software after color deconvolution. The quantitative analysis of 66 cases of invasive lobular BC included: Percent of ER-positive cells, average nuclear coloration intensity, and the quantitative ER score. The percent of ER-positive tumor cells was counted using a standard grid overlay, while optical density (0.0-1.0) was measured within each nucleus at the grid points. RESULTS: A statistical analysis revealed a significant positive correlation (r = 0.886, p < 0.001) between the subjective semi-quantitative and quantitative ER scores, with a large effect size (d = 3.8215). We observed strong statistically significant correlations between individual parameters of the total ER score, percentage of ER-positive nuclei, and color intensity, obtained by the two independent methods. CONCLUSIONS: Additionally, besides excluding subjectivity, the up to now unreported cases of 3 + 0, 4 + 0, and 5 + 0 Allred scores were detected only by the application of the proposed quantitative approach.


Assuntos
Neoplasias da Mama/química , Neoplasias da Mama/imunologia , Receptores de Estrogênio/análise , Adulto , Feminino , Humanos , Imuno-Histoquímica/métodos , Pessoa de Meia-Idade , Receptores de Estrogênio/imunologia , Projetos de Pesquisa/tendências
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