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1.
Mol Biol Rep ; 51(1): 746, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874663

RESUMO

BACKGROUND: Human Amniotic Membrane (hAM) is endowed with several biological activities and might be considered an optimal tool in surgical treatment for different ophthalmic pathologies. We pioneered the surgical use of hAM to treat retinal pathologies such as macular holes, tears, and retinal detachments, and to overcome photoreceptor damage in age-related macular degeneration. Although hAM contributed to improved outcomes, the mechanisms of its effects are not yet fully understood. The characterization and explanation of the effects of hAM would allow the adoption of this new natural product in different retinal pathologies, operative contexts, and hAM formulations. At this end, we studied the properties of a hAM extract (hAME) on the ARPE-19 cells. METHODS AND RESULTS: A non-denaturing sonication-based technique was developed to obtain a suitable hAME. Viability, proliferation, apoptosis, oxidative stress, and epithelial-mesenchymal transition (EMT) were studied in hAME-treated ARPE-19 cells. The hAME was able to increase ARPE-19 cell viability even in the presence of oxidative stress (H2O2, TBHP). Moreover, hAME prevented the expression of EMT features, such as EMT-related proteins, fibrotic foci formation, and migration induced by different cytokines. CONCLUSIONS: Our results demonstrate that the hAME retains most of the properties observed in the whole tissue by others. The hAME, other than providing a manageable research tool, could represent a cost-effective and abundant drug to treat retinal pathologies in the future.


Assuntos
Âmnio , Apoptose , Proliferação de Células , Sobrevivência Celular , Estresse Oxidativo , Epitélio Pigmentado da Retina , Humanos , Âmnio/citologia , Âmnio/efeitos dos fármacos , Linhagem Celular , Epitélio Pigmentado da Retina/efeitos dos fármacos , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/citologia , Sobrevivência Celular/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Extratos de Tecidos/farmacologia
2.
Int J Mol Sci ; 24(19)2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37834001

RESUMO

The extensive use of agricultural pesticides to improve crop quality and yield significantly increased the risk to the public of exposure to small but repeated doses of pesticides over time through various routes, including skin, by increasing the risk of disease outbreaks. Although much work was conducted to reduce the use of pesticides in agriculture, little attention was paid to prevention, which could reduce the toxicity of pesticide exposure by reducing its impact on human health. Extra virgin olive oil (EVOO), a major component of the Mediterranean diet, exerts numerous health-promoting properties, many of which are attributed to oleuropein aglycone (OleA), the deglycosylated form of oleuropein, which is the main polyphenolic component of EVOO. In this work, three pesticides with different physicochemical and biological properties, namely oxadiazon (OXA), imidacloprid (IMID), and glyphosate (GLYPHO), were compared in terms of metabolic activity, mitochondrial function and epigenetic modulation in an in vitro cellular model of human HaCaT keratinocytes to mimic the pathway of dermal exposure. The potential protective effect of OleA against pesticide-induced cellular toxicity was then evaluated in a cell pre-treatment condition. This study showed that sub-lethal doses of OXA and IMID reduced the metabolic activity and mitochondrial functionality of HaCaT cells by inducing oxidative stress and altering intracellular calcium flux and caused epigenetic modification by reducing histone acetylation H3 and H4. GLYPHO, on the other hand, showed no evidence of cellular toxicity at the doses tested. Pretreatment of cells with OleA was able to protect cells from the damaging effects of the pesticides OXA and IMID by maintaining metabolic activity and mitochondrial function at a controlled level and preventing acetylation reduction, particularly of histone H3. In conclusion, the bioactive properties of OleA reported here could be of great pharmaceutical and health interest, as they could be further studied to design new formulations for the prevention of toxicity from exposure to pesticide use.


Assuntos
Olea , Praguicidas , Humanos , Piranos/farmacologia , Monoterpenos Ciclopentânicos , Azeite de Oliva , Queratinócitos , Praguicidas/toxicidade , Olea/química
3.
Cell Mol Life Sci ; 77(6): 965-976, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31563996

RESUMO

Crystallins were firstly found as structural proteins of the eye lens. To this family belong proteins, such as ζ-crystallin, expressed ubiquitously, and endowed with enzyme activity. ζ-crystallin is a moonlighting protein endowed with two main different functions: (1) mRNA binding with stabilizing activity; (2) NADPH:quinone oxidoreductase. ζ-crystallin has been clearly demonstrated to stabilize mRNAs encoding proteins involved in renal glutamine catabolism during metabolic acidosis resulting in ammoniagenesis and bicarbonate ion production that concur to compensate such condition. ζ-crystallin binds also mRNAs encoding for antiapoptotic proteins, such as Bcl-2 in leukemia cells. On the other hand, the physiological role of its enzymatic activity is still elusive. Gathering research evidences and data mined from public databases, we provide a framework where all the known ζ-crystallin properties are called into question, making it a hypothetical pivotal player in cancer, allowing cells to hijack or subjugate the acidity response mechanism to increase their ability to resist oxidative stress and apoptosis, while fueling their glutamine addicted metabolism.


Assuntos
Neoplasias/metabolismo , zeta-Cristalinas/metabolismo , Acidose/metabolismo , Amônia/metabolismo , Animais , Apoptose , Glutamina/metabolismo , Humanos , Estresse Oxidativo , Ligação Proteica , RNA Mensageiro/metabolismo
4.
Int J Mol Sci ; 22(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34299320

RESUMO

Chemotherapy is still widely used as a coadjutant in gastric cancer when surgery is not possible or in presence of metastasis. During tumor evolution, gatekeeper mutations provide a selective growth advantage to a subpopulation of cancer cells that become resistant to chemotherapy. When this phenomenon happens, patients experience tumor recurrence and treatment failure. Even if many chemoresistance mechanisms are known, such as expression of ATP-binding cassette (ABC) transporters, aldehyde dehydrogenase (ALDH1) activity and activation of peculiar intracellular signaling pathways, a common and universal marker for chemoresistant cancer cells has not been identified yet. In this study we subjected the gastric cancer cell line AGS to chronic exposure of 5-fluorouracil, cisplatin or paclitaxel, thus selecting cell subpopulations showing resistance to the different drugs. Such cells showed biological changes; among them, we observed that the acquired chemoresistance to 5-fluorouracil induced an endothelial-like phenotype and increased the capacity to form vessel-like structures. We identified the upregulation of thymidine phosphorylase (TYMP), which is one of the most commonly reported mutated genes leading to 5-fluorouracil resistance, as the cause of such enhanced vasculogenic ability.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacologia , Neovascularização Patológica/induzido quimicamente , Neoplasias Gástricas/irrigação sanguínea , Neoplasias Gástricas/tratamento farmacológico , Antineoplásicos/metabolismo , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Fluoruracila/metabolismo , Humanos , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Paclitaxel/farmacologia , Neoplasias Gástricas/patologia , Talidomida/farmacologia , Timidina Fosforilase/genética , Regulação para Cima/efeitos dos fármacos
5.
Cancer Metastasis Rev ; 38(3): 537-548, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31486976

RESUMO

Gastric cancer is an active topic of clinical and basic research due to high morbidity and mortality. To date, gastrectomy and chemotherapy are the only therapeutic options for gastric cancer patients, but drug resistance, either acquired or primary, is the main cause for treatment failure. Differences in development and response to cancer treatments have been observed among ethnically diverse GC patient populations. In spite of major incidence, GC Asian patients have a significantly better prognosis and response to treatments than Caucasian ones due to genetic discordances between the two populations. Gene therapy could be an alternative strategy to overcome such issues and especially CRISPR/Cas9 represents one of the most intriguing gene-editing system. Thus, in this review article, we want to provide an update on the currently used therapies for the treatment of advanced GC. Graphical abstract.


Assuntos
Terapia Genética/métodos , Neoplasias Gástricas/terapia , Terapia Genética/tendências , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Gástricas/genética
6.
Int J Mol Sci ; 21(8)2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32326163

RESUMO

Gastric cancer (GC) is turning out today to be one of the most important welfare issues for both Asian and European countries. Indeed, while the vast majority of the disease burden is located in China and in Pacific and East Asia, GC in European countries still account for about 100,000 deaths per year. With this review article, we aim to focus the attention on one of the most complex cellular pathways involved in GC proliferation, invasion, migration, and metastasis: the MAP kinases. Such large kinases family is to date constantly studied, since their discovery more than 30 years ago, due to the important role that it plays in the regulation of physiological and pathological processes. Interactions with other cellular proteins as well as miRNAs and lncRNAs may modulate their expression influencing the cellular biological features. Here, we summarize the most important and recent studies involving MAPK in GC. At the same time, we need to underly that, differently from cancers arising from other tissues, where MAPK pathways seems to be a gold target for anticancer therapies, GC seems to be unique in any aspect. Our aim is to review the current knowledge in MAPK pathways alterations leading to GC, including H. pylori MAPK-triggering to derail from gastric normal epithelium to GC and to encourage researches involved in MAPK signal transduction, that seems to definitely sustain GC development.


Assuntos
Sistema de Sinalização das MAP Quinases , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Gástricas/metabolismo , Animais , Biomarcadores , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Suscetibilidade a Doenças , Epigênese Genética , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Helicobacter pylori , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , MicroRNAs/genética , Metástase Neoplásica , Estadiamento de Neoplasias , RNA Longo não Codificante/genética , Neoplasias Gástricas/etiologia , Neoplasias Gástricas/patologia
7.
J Enzyme Inhib Med Chem ; 33(1): 234-240, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29251173

RESUMO

Carbonic anhydrase (CA, EC 4.2.1.1) IX is regarded as a tumour hypoxia marker and CA inhibitors have been proposed as a new class of antitumor agents, with one such agent in Phase II clinical trials. The expression of some CAs, in particular the isoforms CA IX and CA XII, has been correlated with tumour aggressiveness and progression in several cancers. The aim of this study was to evaluate the possibility that CA IX could represent a marker related to clear cell Renal Cell Carcinoma (ccRCC). Bcl-2 and Bax, and the activity of caspase-3, evaluated in tissue biopsies from patients, were congruent with resistance to apoptosis in ccRCCs with respect to healthy controls, respectively. In the same samples, the CA IX and pro-angiogenic factor VEGF expressions revealed that both these hypoxia responsive proteins were strongly increased in ccRCC with respect to controls. CA IX plasma concentration and CA activity were assessed in healthy volunteers and patients with benign kidney tumours and ccRCCs. CA IX expression levels were found strongly increased only in plasma from ccRCC subjects, whereas, CA activity was found similarly increased both in plasma from ccRCC and benign tumour patients, compared to healthy volunteers. These results show that the plasmatic level of CA IX, but not the CA total activity, can be considered a diagnostic marker of ccRCCs. Furthermore, as many reports exist relating CA IX inhibition to a better outcome to anticancer therapy in ccRCC, plasma levels of CA IX could be also predictive for response to therapy.


Assuntos
Biomarcadores Tumorais , Anidrase Carbônica IX/sangue , Carcinoma de Células Renais/sangue , Carcinoma de Células Renais/diagnóstico , Idoso , Western Blotting , Anidrase Carbônica IX/genética , Anidrase Carbônica IX/metabolismo , Carcinoma de Células Renais/enzimologia , Caspase 3/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
9.
J Cell Mol Med ; 19(1): 113-23, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25313007

RESUMO

Gangliosides and the urokinase plasminogen activator receptor (uPAR) tipically partition in specialized membrane microdomains called lipid-rafts. uPAR becomes functionally important in fostering angiogenesis in endothelial progenitor cells (EPCs) upon recruitment in caveolar-lipid rafts. Moreover, cell membrane enrichment with exogenous GM1 ganglioside is pro-angiogenic and opposite to the activity of GM3 ganglioside. On these basis, we first checked the interaction of uPAR with membrane models enriched with GM1 or GM3, relying on the adoption of solid-supported mobile bilayer lipid membranes with raft-like composition formed onto solid hydrophilic surfaces, and evaluated by surface plasmon resonance (SPR) the extent of uPAR recruitment. We estimated the apparent dissociation constants of uPAR-GM1/GM3 complexes. These preliminary observations, indicating that uPAR binds preferentially to GM1-enriched biomimetic membranes, were validated by identifying a pro-angiogenic activity of GM1-enriched EPCs, based on GM1-dependent uPAR recruitment in caveolar rafts. We have observed that addition of GM1 to EPCs culture medium promotes matrigel invasion and capillary morphogenesis, as opposed to the anti-angiogenesis activity of GM3. Moreover, GM1 also stimulates MAPKinases signalling pathways, typically associated with an angiogenesis program. Caveolar-raft isolation and Western blotting of uPAR showed that GM1 promotes caveolar-raft partitioning of uPAR, as opposed to control and GM3-challenged EPCs. By confocal microscopy, we have shown that in EPCs uPAR is present on the surface in at least three compartments, respectively, associated to GM1, GM3 and caveolar rafts. Following GM1 exogenous addition, the GM3 compartment is depleted of uPAR which is recruited within caveolar rafts thereby triggering angiogenesis.


Assuntos
Cavéolas/metabolismo , Células Progenitoras Endoteliais/metabolismo , Gangliosídeo G(M1)/farmacologia , Gangliosídeo G(M3)/farmacologia , Microdomínios da Membrana/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismo , Cavéolas/efeitos dos fármacos , Caveolina 1/metabolismo , Ensaio de Unidades Formadoras de Colônias , Células Progenitoras Endoteliais/efeitos dos fármacos , Humanos , Recém-Nascido , Cinética , Microdomínios da Membrana/efeitos dos fármacos , Fenótipo , Transdução de Sinais
10.
Artigo em Inglês | MEDLINE | ID: mdl-38615071

RESUMO

BACKGROUND: The surgical landscape for Lower Urinary Tract Symptoms (LUTS) and Benign Prostatic Hyperplasia (BPH) has evolved with the introduction of Minimally Invasive Surgical Therapies (MISTs), recognizing the impact of sexual function on patients' well-being, and prioritizing ejaculation-sparing approaches. METHODS: This systematic review explored ejaculation sparing after classic endoscopic procedures and MISTs (iTind, Rezum, Urolift, Aquablation, and TPLA) and a literature search yielded 41 studies. RESULTS: While all procedures demonstrated efficacy in improving LUTS/BPH symptoms (IPSS, QoL, Qmax), a subset of studies evaluated ejaculatory function. Positive outcomes were noted, challenging the historical association of BPH surgeries with ejaculatory dysfunction. Variations in study design, patient cohorts, and limited long-term data present challenges. Notably, the lack of baseline specificity, use of alpha-blockers, and non-specific sexual function assessments underscore potential biases. CONCLUSIONS: Despite limitations, the review tentatively concluded that MISTs, including iTind, Rezum, Urolift, Aquablation, and TPLA, appear comparable in sparing ejaculation. Long-term studies are essential to validate sustainability, and comparative research should assess trade-offs between MISTs and traditional surgeries. Incorporating patient-reported outcomes and quality of life assessments will enhance future investigations, refining MISTs as standard therapeutic options for LUTS/BPH.

11.
Healthcare (Basel) ; 11(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37893879

RESUMO

BACKGROUND: Fall represents one of the highest concerns in the healthcare system, especially in medical rehabilitation settings. However, there is a lack of instruments for the assessment of risk falls in the context of musculoskeletal rehabilitation. METHODS: This retrospective multisite study aimed to assess the sensitivity and specificity of four fall risk assessment tools (the Functional Independence Measure, the Fall Risk Assessment, the Schmid Fall Risk Assessment Tool, and the ePA-AC) in predicting falls in patients admitted to musculoskeletal rehabilitation in Swiss inpatient facilities. RESULTS: The data relative to 6970 individuals (61.5% females) were analyzed and 685 (9.83% of patients) fall events were registered. The area under the curve (AUC) relative to the Functional Independence Measure was 0.689, 0.66 for the Fall Risk Assessment, 0.641 for the Schmid Fall Risk Assessment Tool, and 0.675 for the ePA-AC. Among the four tools, the Functional Independence Measure had an acceptable discriminatory power in distinguishing between significant events (i.e., patients' falls) and non-events (no falls). CONCLUSION: None of the assessed tools showed highly satisfying levels of statistical sensitivity or sensibility. However, the Functional Independence Measure could be used to assess the fall risk assessment in musculoskeletal rehabilitation settings, although with some caution, since this questionnaire was not designed for this diagnostic purpose. We strongly suggest urgently designing a tool for risk assessment that is specific to this population and the rehabilitative setting.

12.
Materials (Basel) ; 16(6)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36984120

RESUMO

Extrusion and hot compressing molding processes were used to create bio-polyethylene (BioPE) composites reinforced with argan byproducts (shell, pulp, and argan cake) as bio-fillers. The thermal stability of the composites wass analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Dynamical mechanical analysis and rheological testing were used to investigate their mechanical properties. The morphological results showed a good adhesion between the argan and BioPE matrix. More efficient mechanical properties have been distinguished in the case of argan byproduct-based composite. A higher Young's modulus was noted for all the biocomposites compared to pure BioPE. Thermal analysis revealed that the addition of bio-filler to polymer reduced decomposition temperatures. This study provides an ecological alternative for upgrading the valorization of abundant and underutilized Moroccan biomass. Furthermore, the possibility of using argan byproducts in composite manufacturing will help open up new markets for what is currently considered waste.

13.
Cancer Lett ; 571: 216338, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37549770

RESUMO

Gastric cancer (GC) is the fifth most frequent malignancy and the fourth leading cause of worldwide cancer-related death. Despite the usage of multimodal perioperative chemotherapy (pCT), GC progressively gains chemoresistance, thereby, the identification of suitable targets to overcome drug resistance is fundamental. Amongst the potential biomarkers, carbonic anhydrase IX (CAIX) - associated with a poor prognosis of several solid cancers - has gained the most attention. In a cohort of GC patients who received perioperative FLOT (i.e., Leucovorin, 5-Fluouracil, Docetaxel, and Oxaliplatin) or FOLFOX (i.e., Leucovorin, 5-Fluouracil, and Oxaliplatin), non-responder patients showed an increased expression of tumor CAIX compared to responder group. Moreover, GC cell lines induced to be resistant to 5-Fluouracil, Paclitaxel, Cisplatin, or the combination of 5-Fluorouracil, Oxaliplatin, and Docetaxel, overexpressed CAIX compared to the control. Accordingly, CAIX-high-expressing GC cells showed increased therapy resistance compared to low-expressing cells. Notably, SLC0111 significantly improved the therapy response of both wild-type and resistant GC cells. Overall, these data suggest a correlation between CAIX and GC drug resistance highlighting the potential of SLC-0111 in re-sensitizing GC cells to pCT.


Assuntos
Antineoplásicos , Inibidores da Anidrase Carbônica , Neoplasias Gástricas , Humanos , Antígenos de Neoplasias/metabolismo , Antineoplásicos/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Anidrase Carbônica IX/genética , Anidrase Carbônica IX/metabolismo , Linhagem Celular , Docetaxel/farmacologia , Fluoruracila/farmacologia , Leucovorina/farmacologia , Oxaliplatina/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Taxoides/farmacologia , Taxoides/uso terapêutico , Linhagem Celular Tumoral
14.
Materials (Basel) ; 15(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36363169

RESUMO

Fused deposition modelling is a rapidly growing additive manufacturing technology due to its ability to build functional parts with complex geometries. The mechanical properties of a built part depend on several process parameters. The effect of wood content on the properties of 3D printed parts has been studied. Four types of filaments using poly(butylene succinate-co-adipate) (PBSA) with different reinforcement levels of Typha stem powder 0%, 5%, 10%, and 15% by weight were used for 3D printing. The density of the filaments and parts printed in this study increased with the Typha stem powder content. The thermal stability, mechanical performance, and viscoelastic properties of the different biocomposite filaments and 3D printed objects were analysed. The results show an increase in the crystallisation kinetics and a slight decrease in the thermal stability of the biomaterials. Compared to virgin PBSA FDM filaments, the PBSA biocomposite filament filled with Typha stem powder showed an increase in the tensile strength of the parts and specimens from 2.5 MPa to 8 MPa and in the modulus of elasticity from 160 MPa to 375 MPa, respectively, with additions of 5%, 10%, and 15% by mass. The addition of Typha stem fibres generated an increase in the elastic behaviour and relaxation time of the biomaterial structure, visualised by increases in the values of the viscosity components. The surface morphology reveals a decrease in the porosity of the printed samples.

15.
J Int Med Res ; 50(11): 3000605221138843, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36448484

RESUMO

OBJECTIVE: Functional impairments after coronavirus disease 2019 (COVID-19) constitute a major concern in rehabilitative settings; however, evidence assessing the efficacy of rehabilitation programs is lacking. The aim of this study was to verify the clinical characteristics that may represent useful predictors of the short-term effectiveness of multidisciplinary rehabilitation. METHODS: In this real-practice retrospective pre-post intervention cohort study, the short-term effectiveness of a multidisciplinary patient-tailored rehabilitation program was assessed through normalized variations in the Functional Independence Measure in post-acute care patients who had overcome severe COVID-19. Biochemical markers, motor and nutritional characteristics, and the level of comorbidity were evaluated as predictors of functional outcome. Length of stay in the rehabilitation ward was also considered. RESULTS: Following rehabilitation, all participants (n = 53) reported a significant decrease in the level of disability in both motor and cognitive functioning. However, neither motor and nutritional characteristics nor comorbidities played a significant role in predicting the overall positive change registered after rehabilitation. CONCLUSIONS: The results support the existing sparse evidence addressing the importance of an early rehabilitation program for patients who received intensive care and post-acute care due to severe COVID-19.


Assuntos
COVID-19 , Humanos , Estudos de Coortes , Estudos Retrospectivos , Sobreviventes , Cuidados Críticos
16.
FASEB J ; 24(6): 1852-65, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20103721

RESUMO

The human antiapoptotic bcl-2 gene has been discovered in t(14;18) B-cell leukemias/lymphomas because of its overexpression caused at a transcriptional control level by the bcl-2/IgH fusion gene. We were the first to disclose the post-transcriptional control of bcl-2 expression mediated by interactions of an adenine + uracil (AU)-rich element (ARE) in the 3'-UTR of bcl-2 mRNA with AU-binding proteins (AUBPs). Here, we identify and characterize zeta-crystallin as a new bcl-2 AUBP, whose silencing or overexpression has impact on bcl-2 mRNA stability. An increased Bcl-2 level observed in normal phytohemagglutinin (PHA)-activated T lymphocytes, acute lymphatic leukemia (ALL) T-cell lines, and T cells of patients with leukemia in comparison with normal non-PHA-activated T lymphocytes was concomitant with an increase in zeta-crystallin level. The specific association of zeta-crystallin with the bcl-2 ARE was significantly enhanced in T cells of patients with ALL, which accounts for the higher stability of bcl-2 mRNA and suggests a possible contribution of zeta-crystallin to bcl-2 overexpression occurring in this leukemia.


Assuntos
Regiões 3' não Traduzidas/fisiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/metabolismo , zeta-Cristalinas/metabolismo , Western Blotting , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Feminino , Regulação da Expressão Gênica , Humanos , Imunoprecipitação , Masculino , Pessoa de Meia-Idade , Fito-Hemaglutininas , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Linfócitos T/efeitos dos fármacos , Linfócitos T/patologia , zeta-Cristalinas/antagonistas & inibidores , zeta-Cristalinas/genética
17.
Polymers (Basel) ; 13(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201232

RESUMO

An eco-friendly solution to produce new material for the material extrusion process is to use quarry waste as filler for biopolymer composites. A quarry waste that is still studied little as a filler for polymer composites is pozzolan. In this study, the optimization of the formulations and processing parameters of composites produced with pozzolan and bio-based polyethylene for 3D printing technology was performed. Furthermore, a precision irrigation system in the form of a drip watering cup was designed, printed, and characterized. The results showed that the presence of the pozzolan acted as a reinforcement for the composite material and improved the cohesion between the layers of the 3D printed objects. Furthermore, the optimization of the process conditions made it possible to print pieces of complex geometry and permeable parts for the control of the water flow rates with an order of magnitude in the range from mL/h to mL/day.

18.
Eur J Pharm Biopharm ; 160: 100-124, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33497794

RESUMO

Present study addresses the challenge of incorporating hydrophilic streptomycin sulphate (STRS; log P -6.4) with high dose (1 g/day) into a lipid matrix of SLNs. Cold high-pressure homogenization technique used for SLN preparation achieved 30% drug loading and 51.17 ± 0.95% entrapment efficiency. Polyethylene glycol 600 as a supporting-surfactant assigned small size (218.1 ± 15.46 nm) and mucus-penetrating property. It was conceived to administer STRS-SLNs orally rather than intramuscularly. STRS-SLNs remained stable on incubation for varying times in SGF or SIF. STRS-SLNs were extensively characterised for microscopic (TEM and AFM), thermal (DSC), diffraction (XRD) and spectroscopic (NMR and FTIR) properties and showed zero-order controlled release. Enhanced (60 times) intracellular uptake was observed in THP-1 and Pgp expressing LoVo and DLD-1 cell lines, using fluorescein-SLNs. Presence of SLNs in LoVo cells was also revealed by TEM studies. STRS-SLNs showed 3 times reduction in MIC against Mycobacterium tuberculosis H37RV (256182) in comparison to free STRS. It also showed better activity against both M. bovis BCG and Mycobacterium tuberculosis H37RV (272994) in comparison to free STRS. Cytotoxicity and acute toxicity studies (OECD 425 guidelines) confirmed in vitro and in vivo safety of STRS-SLNs. Single-dose oral pharmacokinetic studies in rat plasma using validated LCMS/MS technique or the microbioassay showed significant oral absorption and bioavailability (160% - 710% increase than free drug).


Assuntos
Antituberculosos/administração & dosagem , Portadores de Fármacos/química , Mycobacterium bovis/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Estreptomicina/administração & dosagem , Administração Oral , Animais , Antituberculosos/química , Antituberculosos/farmacocinética , Antituberculosos/toxicidade , Disponibilidade Biológica , Relação Dose-Resposta a Droga , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipídeos/química , Macrófagos/metabolismo , Masculino , Testes de Sensibilidade Microbiana , Nanopartículas/química , Tamanho da Partícula , Ratos , Solubilidade , Estreptomicina/química , Estreptomicina/farmacocinética , Estreptomicina/toxicidade , Células THP-1 , Testes de Toxicidade Aguda
19.
J Drug Target ; 29(6): 631-650, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33410357

RESUMO

The present study describes a special lipid-polyethylene glycol matrix solid lipid nanoparticles (SLNs; 138 nm; -2.07 mV) for ocular delivery. Success of this matrix to encapsulate (entrapment efficiency - 62.09%) a hydrophilic drug, fluconazole (FCZ-SLNs), with no burst release (67% release in 24 h) usually observed with most water-soluble drugs, is described presently. The system showed 164.64% higher flux than the marketed drops (Zocon®) through porcine cornea. Encapsulation within SLNs and slow release did not compromise efficacy of FCZ-SLNs. Latter showed in vitro and in vivo antifungal effects, including antibiofilm effects comparable to free FCZ solution. Developed system was safe and stable (even to sterilisation by autoclaving); and showed optimal viscosity, refractive index and osmotic pressure. These SLNs could reach up to retina following application as drops. The mechanism of transport via corneal and non-corneal transcellular pathways is described by fluorescent and TEM images of mice eye cross sections. Particles streamed through the vitreous, crossed inner limiting membrane and reached the outer retinal layers.


Assuntos
Antifúngicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Fluconazol/administração & dosagem , Lipossomos , Nanopartículas , Animais , Antifúngicos/farmacocinética , Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Linhagem Celular , Química Farmacêutica/métodos , Córnea/metabolismo , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Feminino , Fluconazol/farmacocinética , Fluconazol/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Polietilenoglicóis/química , Segmento Posterior do Olho/metabolismo , Coelhos , Ratos , Suínos , Distribuição Tecidual
20.
Biochim Biophys Acta ; 1793(7): 1182-90, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19328214

RESUMO

We previously showed that, in the rat hepatoma cell line HTC, TNF brings about a non-caspase-dependent, apoptosis-like process requiring NADPH oxidase activity, an iron-mediated pro-oxidant status, and a functional acidic vacuolar compartment. This process may thus involve mechanisms such as autophagy or relocation of lysosomal enzymes, perhaps secondary to the formation of ceramide by acidic sphingomyelinase. Here we investigated whether ceramide formation contributes to the apoptogenic process. HTC cells were found to be sensitive to exogenous ceramide and significantly protected against TNF by desipramine, an inhibitor of lysosomal acid sphingomyelinase. However, Bcl-2 transfection and Bcl-x(L) upregulation by dexamethasone significantly diminished the apoptogenic effect of ceramide but not that of TNF, suggesting that ceramide is not directly involved in TNF toxicity. Moreover, Bcl-x(L) silencing precluded dexamethasone-induced protection against ceramide and, by itself, induced massive death, demonstrating the strict dependence of HTC cells on Bcl-x(L) for survival also under standard culture conditions.


Assuntos
Carcinoma Hepatocelular/metabolismo , Ceramidas/toxicidade , Neoplasias Hepáticas Experimentais/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/toxicidade , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Neoplasias Hepáticas Experimentais/patologia , Lisossomos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , Ratos , Células Tumorais Cultivadas , Proteína bcl-X/antagonistas & inibidores , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
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