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1.
Brain Res ; 1834: 148893, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38554797

RESUMO

Parkinson's disease (PD) is characterized by the progressive loss of dopaminergic neurons in the substantia nigra. The dopamine D3 receptor (D3R) plays a significant role in the pathogenesis and treatment of PD. Activation of receptor tyrosine kinases (RTKs) inhibits signaling mediated by G protein-coupled receptor (GPCR). Epidermal growth factor receptors (EGFRs) and dopamine D3 receptors in the brain are directly associated with PD, both in terms of its development and potential treatment. Therefore, we investigated the impact of modulating the EGFR, a member of the RTKs family, and the dopamine D3R, a member of the GPCR family. In the present study, 100 mg/kg of lapatinib (LAP) was administered to rotenone-intoxicated rats for three weeks. Our findings indicate that LAP effectively alleviated motor impairment, improved histopathological abnormalities, and restored dopaminergic neurons in the substantia nigra. This restoration was achieved through the upregulation of dopamine D3R and increase of tyrosine hydroxylase (TH) expression, as well as boosting dopamine levels. Furthermore, LAP inhibited the activity of p-EGFR, GRK2, and SCR. Additionally, LAP exhibited antioxidant properties by inhibiting the 4-hydroxynonenal (4-HNE) and PLCγ/PKCßII pathway, while enhancing the antioxidant defense mechanism by increasing GSH-GPX4 pathway. The current study offers insights into the potential repositioning of LAP as a disease-modifying drug for PD. This could be achieved by modulating the dopaminergic system and curbing oxidative stress.


Assuntos
Neurônios Dopaminérgicos , Receptores ErbB , Lapatinib , Transtornos Parkinsonianos , Receptores de Dopamina D3 , Rotenona , Animais , Masculino , Ratos , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Receptores ErbB/metabolismo , Receptores ErbB/antagonistas & inibidores , Lapatinib/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/induzido quimicamente , Receptores de Dopamina D3/metabolismo , Receptores de Dopamina D3/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
3.
Neuroscience ; 537: 32-46, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38040085

RESUMO

Parkinson's disease (PD) is the second most common neurodegenerative disease, characterized by abnormal α-synuclein misfolding and aggregation, mitochondrial dysfunction, oxidative stress, as well as progressive death of dopaminergic neurons in the substantia nigra. Molecular chaperones play a role in stabilizing proteins and helping them achieve their proper structure. Previous studies have shown that overexpression of heat shock protein 90 (HSP90) can lead to the death of dopaminergic neurons associated with PD. Inhibiting HSP90 is considered a potential treatment approach for neurodegenerative disorders, as it may reduce protein aggregation and related toxicity, as well as suppress various forms of regulated cell death (RCD). This review provides an overview of HSP90 and its role in PD, focusing on its modulation of proteostasis and quality control of LRRK2. The review also explores the effects of HSP90 on different types of RCD, such as apoptosis, chaperone-mediated autophagy (CMA), necroptosis, and ferroptosis. Additionally, it discusses HSP90 inhibitors that have been tested in PD models. We will highlight the under-investigated neuroprotective effects of HSP90 inhibition, including modulation of oxidative stress, mitochondrial dysfunction, PINK/PARKIN, heat shock factor 1 (HSF1), histone deacetylase 6 (HDAC6), and the PHD2-HSP90 complex-mediated mitochondrial stress pathway. By examining previous literature, this review uncovers overlooked neuroprotective mechanisms and emphasizes the need for further research on HSP90 inhibitors as potential therapeutic strategies for PD. Finally, the review discusses the potential limitations and possibilities of using HSP90 inhibitors in PD therapy.


Assuntos
Doenças Mitocondriais , Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas de Choque Térmico HSP90/uso terapêutico , Chaperonas Moleculares/metabolismo
4.
J Exp Orthop ; 10(1): 107, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37878123

RESUMO

PURPOSE: Current therapies for osteoarthritis (OA) are limited to analgesics and anti-inflammatory drugs. Considering the importance of oxidative stress and inflammatory mediators in OA etiology, we tested the hypothesis that targeting the renin-angiotensin-aldosterone system (RAAS) can improve OA anomalies. Diminazene (DIZE), an activator of angiotensin-converting enzyme 2 and the angiotensin 2 type-1 receptor blocker losartan (LOS) were used for this purpose. METHODS: OA was induced by a single intra-articular injection of monosodium iodoacetate. The effects of exposure to DIZE or LOS for 21 days on OA anomalies in rats' knees were investigated. Evaluation of motor function, nociception, and inflammatory response was done using rotarod, knee bend and knee swelling tests. Markers of knee joint inflammation, and cellular oxidation in addition to the RAAS biomarkers, were assessed in knee tissues, along with radiological and histopathological investigations. RESULTS: Elevations in inflammatory and oxidative markers in knee tissues of OA rats were mostly improved by the two therapeutic drugs. Such effect was also reflected in the rotarod, knee bend and knee swelling tests. Treatment with DIZE has shown a more prominent effect than LOS in controlling OA-associated inflammation and cellular oxidation. Markers of RAAS have also shown better responsiveness to DIZE over LOS. CONCLUSIONS: DIZE has shown a prominent increase in the angiotensin 1-7 amount, highlighting the involvement of the signaling pathway in the immunomodulatory effect. The radiological and histopathology examination came to confirm the outcome of biochemical markers, nominating diminazene aceturate as a possible therapeutic option for OA.

5.
Food Chem Toxicol ; 181: 114069, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37820786

RESUMO

Parkinson's disease (PD) is characterized by motor impairments and progressive dopaminergic neuronal death in the substantia nigra (SN). Recently, the involvement of other regulated cell death (RCD) machineries has been highlighted in PD. Necroptosis is controlled by p-RIPK1, p-RIPK3, and p-MLKL and negatively regulated by caspase-8. Ferroptosis is characterized by iron overload and accumulation of reactive oxygen species. Interestingly, the molecular chaperone complex HSP90/CDC37 has been reported to directly regulate necroptosis, ferroptosis, and some PD-associated proteins. We investigated the potential anti-necroptotic and anti-ferroptotic effects of the anti-cancer drug pazopanib, uncovering the HSP90/CDC37 complex as a master RCD modulator in rotenone-induced Parkinsonism in rats. Oral administration of 15 mg/kg pazopanib to rotenone-intoxicated rats for three weeks improved motor deficits, debilitated histopathological changes, and increased striatal dopaminergic levels. Pazopanib suppressed LRRK2 and c-Abl. Pazopanib displayed an anti-necroptotic effect through inhibition of the p-RIPK1/p-RIPK3/p-MLKL pathway and activation of caspase-8. Moreover, pazopanib inhibited the ferroptotic p-VEGFR2-PKCßII-PLC-γ-ACSL-4 pathway, iron, 4-HNE, and PTGS2 while increasing GPX-4 and GSH levels. Taken together, the current research sheds light on the repositioning of pazopanib targeting HSP90/CDC37 and its multiple RCD mechanisms, which would offer a new perspective for therapeutic strategies in PD.


Assuntos
Ferroptose , Doença de Parkinson , Transtornos Parkinsonianos , Ratos , Animais , Rotenona/toxicidade , Caspase 8/metabolismo , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/tratamento farmacológico , Doença de Parkinson/metabolismo , Dopamina/metabolismo , Chaperonas Moleculares/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo
6.
Inflammopharmacology ; 31(6): 3263-3279, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37725260

RESUMO

The implication of the tissue-localized renin-angiotensin system (RAS) in the pathogenesis of osteoarthritis (OA) has been documented in the last decades. A combination of intraarticular (IA) corticosteroid and hyaluronic acid (HYAL) is approved for pain relief in patients with mild to moderate OA. Combining HYAL with an activator of angiotensin-converting enzyme 2, diminazen aceturate (DIZE), was evaluated in this study for its therapeutic potential. Monosodium iodoacetate was used to induce OA. The effects of daily administration of DIZE versus once-per-week IA injection of HYAL and a combination of both drugs for 21 days on OA deformities in rats' knees were observed. Evaluation of motor activities, pain, and inflammatory response was done using rotarod, knee bend, and knee swelling tests. RAS components, inflammatory biomarkers, and oxidative stress mediators were measured in the knee joint. X-ray radiological examination and histopathological investigations were used to assess joint degeneration and regeneration. Levels of both inflammatory and oxidative markers in knee joint homogenate of OA rats rose, and these increments were mostly improved by the three therapies with a more prominent effect of the drug combination, an effect that was also reflected in the behavioral tests. RAS markers have shown better responsiveness to the combination therapy over both drugs individually, showing a pronounced increase in the angiotensin 1-7 amount. Both radiological and histopathology investigations came to confirm the biochemical results, nominating a combination of HYAL and DIZE as a possible therapeutic option for OA.


Assuntos
Ácido Hialurônico , Peptidil Dipeptidase A , Humanos , Ratos , Animais , Ácido Hialurônico/farmacologia , Enzima de Conversão de Angiotensina 2 , Roedores , Dor
7.
Eur J Pharmacol ; 954: 175875, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37385578

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by motor deficits induced by dopaminergic neuronal death in the substantia nigra (SN). Finding a successful neuroprotective therapy is still challenging despite improved knowledge of the etiology of PD and a variety of medications intended to reduce symptoms. Lapatinib (LAP), an FDA-approved anti-cancer medication, has been stated to exert its effect through the modulation of oxidative stress. Furthermore, recent studies display the neuroprotective effects of LAP in epilepsy, encephalomyelitis, and Alzheimer's disease in rodent models through the modulation of oxidative stress and ferroptosis. Nevertheless, it is questionable whether LAP exerts neuroprotective effects in PD. In the current study, administration of 100 mg/kg LAP in rotenone-treated rats for 21 days ameliorates motor impairment, debilitated histopathological alterations, and revived dopaminergic neurons by increasing tyrosine hydroxylase (TH) expression in SN, along with increased dopamine level. LAP remarkably restored the antioxidant defense mechanism system, GPX4/GSH/NRF2 axis, inhibiting oxidative markers, including iron, TfR1, PTGS2, and 4-HNE, along with suppression of p-EGFR/c-SRC/PKCßII/PLC-γ/ACSL-4 pathway. Moreover, LAP modulates HSP90/CDC37 chaperone complex, regulating many key pathological markers of PD, including LRRK2, c-ABL, and α-syn. It is concluded that LAP has neuroprotective effects in PD via modulation of many key parameters implicated in PD pathogenesis. Taken together, the current study offers insights into the potential repositioning of LAP as a disease-modifying drug in PD.


Assuntos
Antineoplásicos , Fármacos Neuroprotetores , Doença de Parkinson , Ratos , Animais , Doença de Parkinson/metabolismo , Rotenona/farmacologia , Lapatinib/farmacologia , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/metabolismo , Reposicionamento de Medicamentos , Neurônios Dopaminérgicos , Estresse Oxidativo , Antineoplásicos/uso terapêutico , Modelos Animais de Doenças
8.
Artigo em Inglês | MEDLINE | ID: mdl-36625081

RESUMO

The study area is located between longitude 33° 18' 00" - 33° 21' 00" E and latitude 28° 59' - 29° 01' N and covers approximately 700 km2. Uranium and thorium isotopes were determined by alpha spectrometry. The activity concentrations of 238U, 234U and 235U were ranged between 245.5 ± 8.3-465.2 ± 15.2 Bq.kg-1 with an average 345.5 ± 10.4-452.5 ± 9.3 Bq.kg-1 and 890.5 ± 21.3 Bq.kg-1 with an average 632.3 ± 14.9-11.40 ± 0.5 Bq.kg-1 and 21.50 ± 1.4 Bq.kg-1, respectively. The activity concentration of 232Th, 230Th and 228Th were ranged between 153.1 ± 0.3-318.1 ± 2.9 Bq.kg-1, 149.5 ± 0.7-280.8 ± 2.2 Bq.kg-1 and 36.9 ± 0.1-60.5 ± 0.9 Bq.kg-1. The 230Th/232Th activity ratios in all samples were lower than 20, indicating that these samples have been contaminated by detrital 230Th. Th/U ratio varied between 1.3 and 2.1 with an average 1.8; all values were lower than 3.5, indicated enrichment of uranium. 234U/238U activity ratios that higher than unity indicates that an isotope of uranium has migrated within the rock. From the isotopes of uranium and thorium and their activity ratios, the isochron age for the collected samples was about 58.96 ka.


Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo , Urânio , Tório/análise , Urânio/análise , Egito , Poluentes Radioativos do Solo/análise , Análise Espectral , Monitoramento de Radiação/métodos
9.
Ageing Res Rev ; 85: 101841, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36608709

RESUMO

Parkinson's disease (PD) is the second most prevalent neurodegenerative disorder in the world. Motor impairment seen in PD is associated with dopaminergic neurotoxicity in the striatum, and dopaminergic neuronal death in the substantia nigra pars compacta. Cell death has a significant effect on the development and progression of PD. Extensive research over the last few decades has unveiled new regulated cell death (RCD) mechanisms that are not dependent on apoptosis such as necroptosis, ferroptosis, and others. In this review, we will overview the mechanistic pathways of different types of RCD. Unlike accidental cell death, RCD subroutines can be regulated and the RCD-associated kinases are potential druggable targets. Hence, we will address an overview and analysis of different kinases regulating apoptosis such as receptor-interacting protein kinase 1 (RIPK-1), RIPK3, mixed lineage kinase (MLK), Ataxia telangiectasia muted (ATM), cyclin-dependent kinase (CDK), death-associated protein kinase 1 (DAPK1), Apoptosis-signaling kinase-1 (ASK-1), and Leucine-rich repeat kinase-2 (LRRK2). In addition to the role of RIPK1, RIPK3, and Mixed Lineage Kinase Domain like Pseudokinase (MLKL) in necroptosis. We also overview functions of AMP-kinase (AMPK), protein kinase C (PKC), RIPK3, and ATM in ferroptosis. We will recap the anti-apoptotic, anti-necroptotic, and anti-ferroptotic effects of different kinase inhibitors in different models of PD. Finally, we will discuss future challenges in the repositioning of kinase inhibitors in PD. In conclusion, this review kicks-start targeting RCD from a kinases perspective, opening novel therapeutic disease-modifying therapeutic avenues for PD.


Assuntos
Doenças Neurodegenerativas , Doença de Parkinson , Humanos , Doença de Parkinson/tratamento farmacológico , Proteínas Quinases/metabolismo , Proteínas Quinases/farmacologia , Apoptose , Morte Celular
10.
Clin Exp Med ; 23(1): 131-140, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35066710

RESUMO

It is unclear whether direct-acting antiviral drugs (DAAs) result in the complete eradication of HCV infection or whether some quantities of the virus may persist after achieving a sustained virologic response (SVR). Aim The aim of this work was to study the possibility of the persistence of HCV RNA in peripheral blood mononuclear cells (PBMCs) after achieving SVR following DAA treatment. This study included 100 patients infected with HCV genotype 4, who were candidates for receiving DAAs and who achieved SVR during follow-up, as determined at 12 and/or 24 weeks following the end of treatment. All patients were subjected to demographic, biochemical and hematological assessments. Detection of HCV RNA in the serum and PBMCs and determination of the HCV genotype were performed with real-time PCR. We detected HCV RNA in the PBMCs of 20 out of 100 (20%) patients infected with HCV genotype 4, who achieved SVR. However, the persistent viral load in the PBMCs was very low (range: 400-900 U/mL; mean ± SD: 645.45 ± 153 U/mL). Multiple logistic regression analysis showed that only the higher posttreatment levels of aspartate transaminase (AST) were significantly predictive of HCV RNA persistence in the PBMCs (OR: 1.29; 95% CI: 1.08-1.55). Additionally, according to the Cox proportional hazard model, liver cirrhosis was the only significant risk factor for the persistence of HCV infection in PBMCs (HR: 5.8; 95% CI: 1.3-26.1; P < 0.02). Our results indicated the persistence of HCV RNA in some HCV patients who achieved SVR after treatment with DAAs.


Assuntos
Hepatite C Crônica , Hepatite C , Humanos , Hepacivirus/genética , Antivirais/uso terapêutico , Resposta Viral Sustentada , Leucócitos Mononucleares , Hepatite C Crônica/tratamento farmacológico , RNA Viral/genética , Hepatite C/tratamento farmacológico
11.
Fundam Clin Pharmacol ; 36(5): 869-878, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35384052

RESUMO

Great attention was recently given to the importance of RAS in controlling inflammatory bone diseases, following the discovery of its local existence in skeletal tissues. Local RAS was found to be expressed on osteoblastic and osteoclastic cells and to exert its action via angiotensin II (AngII) receptors, including angiotensin II type 1 receptor (AT1 R) and angiotensin II type 2 receptors. Telmisartan (TLM), an AT1 R blocker (ARBs), was investigated in the present study for its therapeutic effect on bone health in osteoporotic rats. d-Galactose, a reducing sugar at a dose of 200 mg/kg/day/i.p., was used to induce osteoporosis in male rats. TLM, at a dose of 5 mg/kg/day, was orally introduced in the osteoporotic rats for four consecutive weeks. Tibia and femur bone densitometry was estimated, bone formation and bone resorption biomarkers serum levels were measured, mineral content in blood was also valued, and finally the extracellular regulated kinase (ERK) expression in bone was determined. TLM considerably improved the deleterious effect of d-galactose on bone mineral density. It blunted serum bone-specific alkaline phosphatase and osteocalcin while elevating serum osteoprotegrin (OPG). On the other hand, TLM turned off the pronounced elevation in serum receptor activator of nuclear factor-κß ligand (RANKL), tartrate-resistant acid phosphatase, and cathepsin K. Furthermore, it significantly hindered the bone expression of ERK which hampered osteoclastogenesis. AT1 R inhibition abolished the rise in serum calcium and phosphorus and normalized serum superoxide dismutase and catalase. These TLM protective effects in d-galactose-treated rats were confirmed by the histopathological examination. The results all together denote the potential therapeutic value of ARBs therapy in osteoporosis.


Assuntos
Osteogênese , Osteoporose , Angiotensina II , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Animais , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Galactose/farmacologia , Masculino , Osteoclastos/metabolismo , Osteoclastos/patologia , Osteoporose/induzido quimicamente , Osteoporose/tratamento farmacológico , Ratos , Telmisartan/farmacologia , Telmisartan/uso terapêutico
12.
Artigo em Inglês | MEDLINE | ID: mdl-35475393

RESUMO

The black shale is considered one of the most important rock units in the lower part of Um Bogma Formation, where it contains the uranium, heavy metals and rare earth elements mineralization. The black shale samples were analyzed radiochemically by using alpha spectrometry technique. Most of uranium in the studied samples is authigenic and the Th/U ratio confirms the deposition of uranium in reducing environment. The activity ratios of the studied black shale samples were characterized by 234U/238U > 1 and 230Th/234U < 1, which showed relatively recent precipitation of uranium from water in reducing conditions. 234U/235U and 238U/235U activity ratio was relatively deviated from equilibrium due to the changes in the oxidation-reduction conditions. The disequilibrium of 228Th/232Th can be due to the co-precipitation of 228Ra and the migration of 228Th from the black shale into the percolating water. So, the water was percolated through the paleochannels and caves instead of the rocks causing uranium mobilization and the fractionation of uranium, forming the oxidation-reduction interface in the periods from <6 × 104 to >3 × 105 year.


Assuntos
Urânio , Minerais , Urânio/análise , Água
13.
Liver Transpl ; 28(9): 1490-1499, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35289076

RESUMO

Living donors are healthy individuals who are exposed to a major surgical procedure during which a major part of their liver is resected. Data on the long-term consequences of living liver donation are scarce. This study examined clinical, laboratory, and long-term health-related quality of life (HRQoL) in 237 living liver donors and 239 matched controls during 48-168 months of postdonation follow-up. We used the 36-item short-form health survey (SF-36), version 1. The scores for the four following subscales were higher in nondonors than in donors: physical functioning (p = 0.009), role limitations due to physical health (p = 0.002), energy/fatigue (p < 0.001), and bodily pain (p < 0.001). The scores on the eight subscales of the SF-36 were higher in donors with living recipients than in donors whose recipients died (p < 0.001). Our results suggest that living donor right hepatectomy is safe and results in a postdonation HRQoL similar to that of nondonors in those donors whose recipients are healthy, whereas donors whose recipients die have a lower HRQoL that is significantly negatively correlated with the time since recipient death and improves over time.


Assuntos
Transplante de Fígado , Doadores Vivos , Seguimentos , Humanos , Fígado , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Qualidade de Vida , Inquéritos e Questionários
14.
Pharmaceuticals (Basel) ; 15(2)2022 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-35215363

RESUMO

Though quinoline anti-infective agents-associated neurotoxicity has been reported in the early 1970s, it only recently received regulatory recognition. In 2019, the European Medicines Agency enforced strict use for quinoline antibiotics. Thus, the current study evaluates the relation between subacute exposure to diiodohydroxyquinoline (DHQ), a commonly misused amebicide, with the development of motor and sensory abnormalities, highlighting age and gender as possible predisposing factors. Eighty rats were randomly assigned to eight groups according to their gender, age, and drug exposure; namely, four control groups received saline (adult male, adult female, young male, and young female), and the other four groups received DHQ. Young and adult rats received DHQ in doses of 176.7 and 247.4 mg/kg/day, respectively. After 4 weeks, rats were tested for sensory abnormality using analgesiometer, hot plate, and hind paw cold allodynia tests, and for motor function using open field and rotarod tests. Herein, the complex behavioral data were analyzed by principal component analysis to reduce the high number of variables to a lower number of representative factors that extracted components related to sensory, motor, and anxiety-like behavior. Behavioral outcomes were reflected in a histopathological examination of the cerebral cortex, striatum, spinal cord, and sciatic nerve, which revealed degenerative changes as well demyelination. Noteworthy, young female rats were more susceptible to DHQ's toxicity than their counterparts. Taken together, these findings confirm previous safety concerns regarding quinoline-associated neurotoxicity and provide an impetus to review risk/benefit balance for their use.

15.
Comput Math Methods Med ; 2022: 8501828, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35186116

RESUMO

Computed tomography (CT) is a common modality for liver diagnosis, treatment, and follow-up process. Providing accurate liver segmentation using CT images is a crucial step towards those tasks. In this paper, we propose a stacked 2-U-Nets model with three different types of skip connections. The proposed connections work to recover the loss of high-level features on the convolutional path of the first U-Net due to the pooling and the loss of low-level features during the upsampling path of the first U-Net. The skip connections concatenate all the features that are generated at the same level from the previous paths to the inputs of the convolutional layers in both paths of the second U-Net in a densely connected manner. We implement two versions of the model with different number of filters at each level of each U-Net by maximising the Dice similarity between the predicted liver region and that of the ground truth. The proposed models were trained with 3Dircadb public dataset that were released for Sliver and 3D liver and tumour segmentation challenges during MICCAI 2007-2008 challenge. The experimental results show that the proposed model outperformed the original U-Net and 2-U-Nets variants, and is comparable to the state-of-the-art mU-Net, DC U-Net, and Cascaded UNET.


Assuntos
Fígado/diagnóstico por imagem , Redes Neurais de Computação , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Biologia Computacional , Humanos , Imageamento Tridimensional/estatística & dados numéricos , Neoplasias Hepáticas/diagnóstico por imagem , Aprendizado de Máquina , Interpretação de Imagem Radiográfica Assistida por Computador/estatística & dados numéricos
16.
Neural Regen Res ; 17(9): 1913-1918, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35142667

RESUMO

Numerous molecular mechanisms are being examined in an attempt to discover disease-modifying drugs to slow down the underlying neurodegeneration in Alzheimer's disease. Recent studies have shown the beneficial effects of epidermal growth factor receptor inhibitors on the enhancement of behavioral and pathological sequelae in Alzheimer's disease. Despite the promising effects of epidermal growth factor receptor inhibitors in Alzheimer's disease, there is no irrefutable neuroprotective evidence in well-established animal models using epidermal growth factor receptor inhibitors due to many un-explored downstream signaling pathways. This caused controversy about the potential involvement of epidermal growth factor receptor inhibitors in any prospective clinical trial. In this review, the mystery beyond the under-investigation of epidermal growth factor receptor in Alzheimer's disease will be discussed. Furthermore, their molecular mechanisms in neurodegeneration will be explained. Also, we will shed light on SARS-COVID-19 induced neurological manifestations mediated by epidermal growth factor modulation. Finally, we will discuss future perspectives and under-examined epidermal growth factor receptor downstream signaling pathways that warrant more exploration. We conclude that epidermal growth factor receptor inhibitors are novel effective therapeutic approaches that require further research in attempts to be repositioned in the delay of Alzheimer's disease progression.

18.
Molecules ; 26(22)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34834085

RESUMO

Osteoarthritis (OA) is a complex disease characterized by structural, functional, and metabolic deteriorations of the whole joint and periarticular tissues. In the current study, we aimed to investigate the possible effects of tempol on knee OA induced by the chemical chondrotoxic monosodium iodoacetate (MIA) which closely mimics both the pain and structural changes associated with human OA. Rats were administrated oral tempol (100 mg/kg) one week post-MIA injection (3 mg/50 µL saline) at the right knee joints for 21 consecutive days. Tempol improved motor performance and debilitated the MIA-related radiological and histological alterations. Moreover, it subsided the knee joint swelling. Tempol decreased the cartilage degradation-related biomarkers as matrix metalloproteinase-13, bone alkaline phosphatase (bone ALP), and fibulin-3. The superoxide dismutase mimetic effect of tempol was accompanied by decreased NADPH oxidase 4 (NOX4), inflammatory mediators, nuclear factor-kappa B (NF-κB), over-released transforming growth factor-ß1 (TGF-ß1). Tempol decreased the expression of chemokine (C-C motif) ligand 2 (CCL2). On the molecular level, tempol reduced the phosphorylated protein levels of p38 mitogen-activated protein kinase (MAPK), and small mother against decapentaplegic 3 homologs (SMAD3). These findings suggest the promising role of tempol in ameliorating MIA-induced knee OA in rats via collateral suppression of the catabolic signaling cascades including TGF-ß1/SMAD3/NOX4, and NOX4/p38MAPK/NF-κB and therefore modulation of oxidative stress, catabolic inflammatory cascades, chondrocyte metabolic homeostasis.


Assuntos
Óxidos N-Cíclicos/farmacologia , Ácido Iodoacético/efeitos adversos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NADPH Oxidase 4/metabolismo , Osteoartrite do Joelho , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Ácido Iodoacético/farmacologia , Masculino , Osteoartrite do Joelho/induzido quimicamente , Osteoartrite do Joelho/tratamento farmacológico , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Ratos , Ratos Wistar , Marcadores de Spin
19.
Life Sci ; 285: 119983, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34599938

RESUMO

BACKGROUNDS: Modern dietary habits have been associated with Nonalcoholic Steatohepatitis (NASH). Curcumin is a natural herbal found to suppress cellular oxidative states and could be beneficial in NASH. This study investigates the effect of curcumin in an animal model of NASH. MATERIALS AND METHODS: Fifty rats were allocated into five groups. Control, High Fat Diet (HFD), curcumin prophylactic (CP) and therapeutic (CT) groups. HFD regimen was given for 16 weeks. Curcumin was given along with HFD (prophylactic) or after establishment of the model for two weeks (therapeutic). Livers and blood samples were harvested for histological, biochemical, and molecular studies. KEY FINDINGS: Livers from HFD groups showed vascular, inflammatory, cellular degenerative and fibrotic changes. The hepatic damage was reflected by the increased serum liver enzymes. HFD groups showed excessive fibrotic change. Interestingly, curcumin administration as prophylactic or therapeutic significantly preserved and/or restored liver structure. This was evidenced by the normalization of the liver enzymes, preservation and/or reversibility of cellular changes and the decrease of the stage of fibrosis. Nuclear factor E2-related factor 2 gene (Nrf2) expression showed no changes in the HFD groups, however it showed upregulation in curcumin treated groups. Thus, the protective and therapeutic effect of curcumin could be induced through upregulation of the Nrf2 gene. Curcumin has a beneficial prophylactic and therapeutic effect that could hinder the development and/or treat NASH in susceptible livers. SIGNIFICANCE: Curcumin has a beneficial prophylactic and therapeutic effect that could hinder the development and/or treat NASH in susceptible livers.


Assuntos
Curcumina/uso terapêutico , Fígado/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Peso Corporal/efeitos dos fármacos , Colágeno/metabolismo , Curcumina/administração & dosagem , Curcumina/farmacologia , Dieta Hiperlipídica , Fígado/metabolismo , Fígado/ultraestrutura , Masculino , Microscopia Eletrônica , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Ratos , Ratos Sprague-Dawley
20.
Pulm Pharmacol Ther ; 71: 102082, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34601121

RESUMO

COVID-19 pandemic has changed the world dramatically since was first reported in Wuhan city, China [1]. Not only as a respiratory illness that could lead to fatal respiratory failure, but also some evidences suggest that it can propagate as a chronic disease associated with a variety of persistent post COVID-19 pathologies that affect patients' life [2,3]. Pulmonary hypertension (PH) is one of the challenging diseases that may develop as a consequence of SARS-COV-2 infection in some COVID-19 survivors [4,5]. The vasopressor, proliferative, proinflammatory, and prothrombotic actions of endothelin [6] may be encountered in the COVID-19-induced PH pathology. And so, endothelin blockers may have an important role to restrict the development of serious PH outcomes with special precautions considering patients with significant hypoxemia.


Assuntos
COVID-19 , Endotelinas , Hipertensão Pulmonar , COVID-19/complicações , Humanos , Hipertensão Pulmonar/virologia , Pandemias
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