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1.
Clin Chem Lab Med ; 58(6): 980-993, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31940282

RESUMO

Prostate cancer accounts for around 15% of male deaths in Western Europe and is the second leading cause of cancer death in men after lung cancer. Mounting evidence suggests that prostate cancer deposits exist within a hypoxic environment and this contributes to radio-resistance thus hampering one of the major therapies for this cancer. Recent reports have shown that nitric oxide (NO) donating non-steroidal anti-inflammatory drugs (NSAIDs) reduced tumour hypoxia as well as maintaining a radio-sensitising/therapeutic effect on prostate cancer cells. The aim of this study was to evaluate the impact of hypoxia on the proteome of the prostate and to establish whether NO-NSAID treatment reverted the protein profiles back to their normoxic status. To this end an established hormone insensitive prostate cancer cell line, PC-3, was cultured under hypoxic and normoxic conditions before and following exposure to NO-NSAID in combination with selected other common prostate cancer treatment types. The extracted proteins were analysed by ion mobility-assisted data independent acquisition mass spectrometry (MS), combined with multivariate statistical analyses, to measure hypoxia-induced alterations in the proteome of these cells. The analyses demonstrated that under hypoxic conditions there were well-defined, significantly regulated/differentially expressed proteins primarily involved with structural and binding processes including, for example, TUBB4A, CIRP and PLOD1. Additionally, the exposure of hypoxic cells to NSAID and NO-NSAID agents, resulted in some of these proteins being differentially expressed; for example, both PCNA and HNRNPA1L were down-regulated, corresponding with disruption in the nucleocytoplasmic shuttling process.


Assuntos
Hipóxia Celular/fisiologia , Neoplasias da Próstata/metabolismo , Proteoma/metabolismo , Cromatografia Líquida , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Espectrometria de Massas , Células PC-3 , Proteoma/análise , Proteoma/genética , Proteômica , Regulação para Cima
2.
Bioorg Med Chem ; 22(2): 756-61, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24387865

RESUMO

A series of analogues of the non-steroidal anti-inflammatory drug (NSAID) sulindac 1 were synthesised tethered to nitric oxide (NO) donating functional groups. Sulindac shows antiproliterative effects against immortal PC3 cell lines. It was previously demonstrated that the effect can be enhanced when tethered to NO releasing groups such as nitrate esters, furoxans and sydnonimines. To explore this approach further, a total of fifty-six sulindac-NO analogues were prepared and they were evaluated as NO-releasing cytotoxic agents against prostate cancer (PCa) cell lines. Compounds 1k and 1n exhibited significant cytotoxic with IC50 values of 6.1±4.1 and 12.1±3.2µM, respectively, coupled with observed nitric oxide release.


Assuntos
Antineoplásicos/farmacologia , Óxido Nítrico/química , Neoplasias da Próstata/tratamento farmacológico , Sulindaco/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Estrutura Molecular , Neoplasias da Próstata/patologia , Relação Estrutura-Atividade , Sulindaco/síntese química , Sulindaco/química
3.
Cureus ; 16(1): e51433, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38298275

RESUMO

Background and objective The hypolipidemic statins have been associated with various side effects, and in some cases, adverse reactions in humans and experimental animals, such as myotoxicity, neurobehavioral toxicity, as well as liver and kidney injuries. The purpose of the present study was to examine the possibility of the induction of oxidative stress in the brain and plasma of mice dosed with single or repetitive doses of three statins (atorvastatin, simvastatin, and rosuvastatin). Methods Male Swiss-origin mice were dosed orally with single doses of each of the three statins at 500 or 1000 mg/kg of body weight. Other groups of mice were dosed orally with repeated daily doses of each of the statins at 200 mg/kg of body weight/day for 14 or 28 consecutive days. These doses of statins were chosen to not produce overt toxicity in mice within the time frame allocated for each experiment. Brain and plasma glutathione (GSH) and malondialdehyde (MDA) levels, as well as liver enzymes activities alanine transaminase (ALT) and aspartate transaminase (AST), were determined using commercial kits. Results Single-dose treatments of the mice with the statins at either 500 or 1000 mg/kg significantly and dose-dependently (p < 0.05) reduced the GSH level in the plasma and the whole brain when compared with respective control values. Atorvastatin was the least effective statin, as only the high dose achieved a significant reduction in brain GSH level in comparison with the respective control value. Repetitive administration of the three statins at 200 mg/kg of body weight/day for 14 or 28 consecutive days significantly and time-dependently reduced plasma and brain GSH levels in comparison with respective control values. The oxidative stress biomarker MDA level significantly increased in the plasma and brain of mice following single or repetitive treatments with the three statins, and the most effective one was rosuvastatin. In association with these changes, activities of the liver enzymes ALT and AST were also increased in the plasma with single and repetitive statin treatments, and the most effective one was rosuvastatin. Conclusion The data suggest an association of high doses of three statins (atorvastatin, simvastatin, and rosuvastatin) with the induction of oxidative stress manifested as GSH reduction and MDA elevation as adverse effects in the brain and plasma of mice, which suffered from the additional burden of liver injury. These effects could be the basis of an in-depth exploration of statin adverse effects in experimental animals and to find an animal model, probably the mice, for the induction of adverse effects of statins that target the brain, as well as to shed light on potential statin intolerance outcomes following single-dose treatments in this species.

4.
Cureus ; 16(5): e60417, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38882963

RESUMO

Background and objective Several blood biochemical parameters are used to biomonitor coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Reduced serum cholinesterase (ChE) has been suggested to be a predictive indicator of the severity and outcome of COVID-19 infection. This study aimed to examine serum ChE activity in hospitalized and terminally ill COVID-19 patients with cytokine storm and evaluate the enzyme for the in vitro ChE-inhibitory activity of the organophosphate dichlorvos. Methods We determined the serum ChE activity, electrometrically, among hospitalized COVID-19-cytokine storm patients and their non-cytokine storm counterparts. Aliquots of serum samples from healthy volunteers, COVID-19-cytokine storm patients, and non-cytokine storm COVID-19 patients were pooled separately. They were incubated in vitro for 10 minutes with dichlorvos at 0.25 or 0.5 µM. Serum samples from the three groups were subjected to ChE inhibition temporally (5-60 minutes) by 0.25 µM dichlorvos to evaluate the kinetics of enzyme inhibition using steady-state kinetics. Results Of the 165 hospitalized patients with COVID-19, 33 (20%) suffered from the cytokine storm. Serum ChE activity of female COVID-19 patients with cytokine storm was significantly lower than that of the non-cytokine storm counterparts. Risk analysis of reduced serum ChE activity (≥20%) among the 33 COVID-19 patients with cytokine storm compared to 111 non-cytokine storm COVID-19 patients revealed that the former were significantly at risk of reduced enzyme activity. In vitro, dichlorvos at 0.25 µM and 0.5 µM significantly inhibited serum ChE activity in all the groups. The COVID-19-cytokine storm group was the least affected. Dichlorvos at 0.25 µM progressively (5-60 minutes) inhibited serum ChE activity. The inhibition kinetic parameters in COVID-19-cytokine storm patients showed a decrease in the half-life of inhibition (14.54%), inhibition rate (51.46%), and total inhibition time (14.55%). Conclusions Reduced serum ChE in COVID-19 patients with cytokine storm could be adopted as a potential additional laboratory examination tool for bedside risk assessment. The in vitro inhibition profile of serum ChE activity by dichlorvos in COVID-19-cytokine storm patients suggests reduced susceptibility of the enzyme to inhibition. The response of COVID-19 patients to ChE-inhibiting medications should be cautiously evaluated with prior in vitro tests.

5.
Cureus ; 16(2): e54403, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38505441

RESUMO

The H1-antihistamine diphenhydramine antagonizes cholinesterase inhibitor poisoning in various animal species. One aspect of acute antidotal actions of diphenhydramine is increasing the median lethal doses (LD50) of toxicants. The objective of this meta-analysis was to assess the antidotal action of diphenhydramine against short-term toxicity (LD50) of cholinesterase inhibitors in experimental animals. The experimental studies selected were according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. They were conducted in laboratory animals (mice, rats, and chicks) to determine acute LD50 values of cholinesterase inhibitors (organophosphates, carbamates, and imidocarb) under the influence of diphenhydramine vs. controls. Twenty-eight records were selected from 12 studies on mice (n= 242), rats (n= 27), and young chicks (n= 128). The forest plot of randomized two-group meta-analysis assessed effect size, subgroup analysis, drapery prediction, heterogeneity, publication bias-funnel plot as well as one-group proportions meta-analysis of percent protection. Diphenhydramine significantly increased the combined effect size (i.e. increased LD50) in intoxicated experimental animals in comparison to controls (-3.71, standard error (SE) 0.36, 95%CI -4.46, -2.97). The drapery plot proposed a wide range of confidence intervals. The I2 index of heterogeneity of the combined effect size was high at 81.03% (Q= 142.3, p < 0.0001). Galbraith regression also indicated data heterogeneity; however, the normal quantile plot indicated no outliers. Subgroup analysis indicated significantly high heterogeneity with organophosphates (I2 = 63.72%) and carbamates (I2 = 76.41%), but low with imidocarb (I2 = 51.48%). The funnel plot and Egger regression test (t= -13.7, p < 0.0001) revealed publication bias. The median of the diphenhydramine protection ratio was 1.655, and the related forest plot of one group proportion meta-analysis revealed a statistically high level of protection (0.594, SE 0.083, 95%CI 0.432, 0.756), with high heterogeneity (I2= 99.86). The risk of bias assessment was unclear, while the total score (16 out of 20) of each study leaned towards the side of the low risk of bias. In conclusion, the meta-analysis of LD50 values indicated that diphenhydramine unequivocally protected experimental animals from the acute toxicity of cholinesterase inhibitors. The drug could be an additional antidote against acute poisoning induced by cholinesterase inhibitors, but a word of caution: it is not to be considered as a replacement for the standard antidote atropine sulfate. Further studies are needed to examine the action of diphenhydramine on adverse chronic effects of cholinesterase inhibitors.

6.
Exp Neurol ; 378: 114815, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38762093

RESUMO

Effective data management and sharing have become increasingly crucial in biomedical research; however, many laboratory researchers lack the necessary tools and knowledge to address this challenge. This article provides an introductory guide into research data management (RDM), and the importance of FAIR (Findable, Accessible, Interoperable, and Reusable) data-sharing principles for laboratory researchers produced by practicing scientists. We explore the advantages of implementing organized data management strategies and introduce key concepts such as data standards, data documentation, and the distinction between machine and human-readable data formats. Furthermore, we offer practical guidance for creating a data management plan and establishing efficient data workflows within the laboratory setting, suitable for labs of all sizes. This includes an examination of requirements analysis, the development of a data dictionary for routine data elements, the implementation of unique subject identifiers, and the formulation of standard operating procedures (SOPs) for seamless data flow. To aid researchers in implementing these practices, we present a simple organizational system as an illustrative example, which can be tailored to suit individual needs and research requirements. By presenting a user-friendly approach, this guide serves as an introduction to the field of RDM and offers practical tips to help researchers effortlessly meet the common data management and sharing mandates rapidly becoming prevalent in biomedical research.


Assuntos
Pesquisa Biomédica , Gerenciamento de Dados , Disseminação de Informação , Humanos , Pesquisa Biomédica/métodos , Pesquisa Biomédica/normas , Gerenciamento de Dados/métodos , Disseminação de Informação/métodos , Pesquisadores
7.
Cureus ; 15(11): e48834, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38106718

RESUMO

Background and objective Polypharmacy is prevalent in coronavirus disease 2019 (COVID-19) patients with severe disease. However, information on polypharmacy among COVID-19 patients who also suffer from cytokine storm is scarce. In light of this, the purpose of the present study was to assess the incidence of polypharmacy and in silico prediction of potential body proteins targeted by these drugs among hospitalized COVID-19 patients who were identified to have the additional burden of cytokine storm in the city of Duhok, Kurdistan Region, Iraq. Methods This was a cross-sectional observational study conducted from June 2021 to April 2022; the phenomena of major polypharmacy (six to nine medications) and excessive polypharmacy (≥10 medications) were documented among 33 (15 males and 18 females) COVID-19 patients with cytokine storm during their hospital stay (8-45 days) in Duhok, Kurdistan Region, Iraq. The SwissTargetPrediction program was utilized in silico to predict and identify human body proteins that could be potentially targeted by selected medications involved in polypharmacy. Results All patients had tested positive for COVID-19 via PCR testing, and they showed different signs and symptoms of the disease. None of the patients recovered and all of them deceased. All 33 patients received many therapeutic agents that ranged in number from eight to 20/patient during their hospital stay. The mean number of medications was 15 ± 3. We identified 2/33 (6%) patients with major polypharmacy (eight and nine) and 31/33 (94%) with excessive polypharmacy (15.5 ± 2.7). The total number of medications identified in polypharmacy was 37, excluding vitamins, minerals, and intravenous solutions. The frequency of medications administered was as follows: antibiotics (67, 13.7%), mucolytic agents (56, 11.5%), corticosteroids (54, 11%), anticoagulants (48, 9.8%), antiviral agents (41, 8.4%), antihypertensive agents (32, 6.5%), analgesics (28, 5.7%), antifungal drugs (27, 5.5%), antidiabetics (26, 5.3%), and other medications (2-19, 0.41-3.9%). Using the SwissTargetPrediction program, various drugs including antiviral agents involved in polypharmacy were found to target, in silico, body proteins at a prediction percentage that ranged from 6.7% to 40%. Conclusions Major and extensive polypharmacy conditions were identified in hospitalized COVID-19 patients suffering from cytokine storm. The severity of COVID-19 with cytokine storm, comorbidities, and hospitalization were key factors associated with polypharmacy in the patients. The SwissTargetPrediction web server is useful for predicting in silico potential human body protein targets that could possibly be sources of additional information on the adverse/toxic effects of polypharmacy medications administered concurrently. Further research in current medication protocols prescribed for advanced COVID-19 illness with cytokine storm is warranted to gain deeper insights into the topic.

8.
Cureus ; 15(12): e50979, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38259372

RESUMO

Background and objective Rheumatoid arthritis (RA) is a chronic autoimmune disease causing synovium inflammation and functional impairment. Toxoplasmosis is an intracellular zoonotic parasitic infection and a risk factor in immunosuppressed diseases including RA. The involvement of the cholinergic mechanism is not clear when both diseases exist in combination. This study aimed to examine plasma cholinesterase (ChE) activity in patients suffering from RA with concomitant toxoplasmosis, taking into account the enzyme susceptibility to in vitro inhibitory challenge with the organophosphate dichlorvos in RA patients. Methods This was a case-control study involving 88 RA patients and 61 healthy controls of both genders. The RA patients were allocated into three groups. The first group received no therapy (n=14), the second group received conventional anti-arthritis therapy (n=49), and the third group received conventional + biologic therapy (n=25). Plasma ChE activity was determined by an electrometric method. Plasma samples were screened for Toxoplasma gondii (T. gondii) infection, using ELISA T. gondii antibodies IgG and IgM. In vitro inhibition of plasma ChE activity was assessed by incubating the samples with dichlorvos at 0.25 and 0.5 µM. The time-dependent dichlorvos (0.25 µM)-induced plasma ChE inhibition and its kinetics were determined. Results The RA patients comprised 76 (86.4%) females and 12 males (13.6%), whereas healthy controls included 22 (36.1%) females and 39 (63.9%) males. The rates of toxoplasmosis IgG positivity in controls and RA patients were 26.2% and 39.8%, respectively. Plasma ChE activity in patients with RA was significantly higher than that in the control group, by 16%. Plasma ChE values of RA patients with conventional therapy and conventional + biologic therapy were higher than that of the control group, by 18% and 27%, respectively. Odds and risk ratios of elevated plasma ChE activity (20%) in RA patients with therapy indicated that high plasma ChE activity among RA patients with therapy is a risk factor. The plasma ChE activity of T. gondii IgG-positive RA patients was not significantly different from that of the IgG-negative ones. Dichlorvos at 0.25 and 0.5 µM significantly inhibited in vitro plasma ChE activity in controls and RA patients. The rates of plasma ChE inhibition by dichlorvos were lower in the RA groups with conventional therapy in comparison with those in the control group (77% vs. 91%). Examining the dichlorvos time-dependent ChE inhibition kinetics, RA groups showed increases in the half-life of inhibition by 23.6% to 32.7% and the total inhibition time by 23.5% to 32.5%, together with decreases in the inhibition rate constant by 19% to 24.5%, an indication of reduced inhibition rate of plasma ChE activity compared to that of the control group. Conclusions The autoimmune nature of RA and its chronicity might have contributed to the increase in plasma ChE activity among the patients. This increase in enzyme activity could be a risk factor in RA patients undergoing conventional therapy alone or in combination with biologic therapy; however, the clinical significance of such a condition remains obscure at present. The in vitro inhibition of plasma ChE activity in RA patients suggests reduced susceptibility of the enzyme to ChE inhibition by dichlorvos. Toxoplasmosis was not a risk factor when plasma ChE activity was taken into account among RA patients.

9.
Cureus ; 15(10): e47220, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38022101

RESUMO

Blood butyrylcholinesterase (BChE) activity has been found to decrease during pregnancy and reportedly decrease even more in preeclampsia (PE). The purpose of the present meta-analysis was to answer a specific question of whether BChE activity (in the plasma, serum, or whole blood) is reduced in pregnant women suffering from PE compared to those with normal pregnancy. The meta-analysis included 15 studies with 20 records of BChE activity in 608 women compared to 569 healthy pregnant (control) ones. The studies were subjected to quality assessment using the Newcastle-Ottawa Scale (NOS). Using the Meta-Essentials software program 1.5, the one-group random effects model and forest plot revealed that the percentage of BChE activity in pregnant women with PE was 84.84% of the control value, with a standard error of 4.09 and 95% C.I. of 76.28, 93.41, indicating a significant 15.16% reduction in BChE activity in comparison to healthy pregnancy. No significant heterogeneity was seen in the analyzed data and the funnel plot did show publication bias. Subgroup (mild, severe, and unclassified PE) forest plot analysis revealed that the % BChE activities in PE compared to respective healthy pregnancies were 96.28%, 97.08%, and 76.62%, respectively with no heterogeneity. The median NOS score of the 15 studies included in the meta-analysis was 7, ranging from 5 to 8 (medium to high quality), and the forest plot showed an effect size of 0.735. This meta-analysis shows that BChE activity is reduced in PE compared with normal pregnancy and its value as a biomarker warrants further clinical studies.

10.
Vet World ; 16(1): 118-125, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36855355

RESUMO

Background and Aim: Diphenhydramine is an H1-antihistamine that counteracts the toxic effects of organophosphate and carbamate insecticides that inhibit cholinesterase (ChE) activity. This meta-analysis aimed to investigate the effects of diphenhydramine on ChE inhibition induced by these insecticides in the plasma, erythrocytes, or whole brain of experimental animals. Materials and Methods: A data search was performed on erythrocyte, plasma, and brain ChE inhibition caused by organophosphate and carbamate insecticides in experimental animals (mice, rats, and chicks) treated with the antihistamine diphenhydramine in accordance with preferred reporting items for systematic reviews and meta-analysis, which was done by the two-group random-effects model meta-analysis. The meta-analysis included 18 records extracted from six studies that, appeared from 1996 to 2022. Results: Using the random-effects model, a two-group meta-analysis revealed that the combined effect size (ChE inhibition) was significantly more favorable in the control group than in the diphenhydramine intervention, as shown by a forest plot. The combined effect size (standardized mean difference) was 0.67, with a standard error of 0.3, a lower limit of 0.04, and an upper limit of 1.29 (p = 0.025). The heterogeneity was moderate, as I2 of the combined effect size was 74%, with a significant Cochrane Q-test result (Q = 65, p < 0.0001). Subgroup analysis indicated that, with brain ChE inhibition, the heterogeneity (I2) became 5%, which was lower than ChE inhibition in plasma (84%) and erythrocytes (78%). No publication bias was identified using the funnel plot and Egger's test. Conclusion: This meta-analysis suggests that, in addition to its documented antidotal action against ChE-inhibiting insecticides, diphenhydramine can also reduce the extent of ChE inhibition, especially in the brain, which is the main site of toxicity of these insecticides. There is a need for additional studies to assess such enzyme inhibition in different parts of the brain.

11.
Zootaxa ; 5389(3): 301-330, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38221021

RESUMO

An updated account of the diversity of parrotfishes from the Socotra Archipelago is provided. Fourteen species are positively recorded based on underwater observations, photography and collections, including confirmations of three species which were previously only tentatively recorded: Scarus falcipinnis(Playfair, 1868), Scarus scaber Valenciennes, 1840 and Scarus tricolorBleeker, 1847. The distribution of Scarus zufar Randall & Hoover, 1995, previously known only from coastal waters of southern Oman, Pakistan and Bangladesh, is extended to the Archipelago, with Abd al-Kuri Island representing the westernmost edge of its known range. Visual records of three additional species are yet to be documented. With 1417species the Archipelago approximates the modal richness range of 1518 species for Arabian ecoregions. A species account, accompanied by photographs, provides distinctive characters, distribution details in the Arabian region, and general remarks for each species. The distributional biogeography of the family pertinent to the Socotra Archipelago and the Arabian region is analysed in the context of the Western Indian Ocean. Three main Arabian units are identified: A Red Sea unit spans the combined Red Sea ecoregions and the western Gulf of Aden; a Socotra unit covers south-eastern Arabia including the Archipelago, the eastern Gulf of Aden and southern Oman; and a Gulf unit combines the Arabian/Persian Gulf, the Gulf of Oman, and putatively central Oman. These units form a discrete pan-Arabian cluster within the wider Western Indian Ocean. The Socotra unit resembles more strongly the Gulf unit than the Red Sea unit. Parrotfishes thus contrast overall distributional patterns of reef fishes in Arabia.


Assuntos
Peixes , Perciformes , Animais
12.
Saudi Dent J ; 35(7): 854-860, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38025603

RESUMO

Objective: to investigate the effectiveness of diluted antibiotic hydrogels in endodontic regeneration procedures. Materials and Methods: One conventional treatment (calcium hydroxide) and two experimental treatments containing 1 mg/mL antibiotic in gel (MC-TAP and MC-DAP) were prepared for this study. The effect of these medicaments on the proliferation and differentiation potential of dental pulp stem cells (DPSCs) was examined before their clinical use, using WST and ALP assays. Twenty-two teeth diagnosed with necrotic immature roots were treated with calcium hydroxide, MC-TAP or MC-DAP using the endodontic regeneration protocol as described by the American Association of Endodontists (AAE). Teeth were examined after application of the medicament, at the time of regeneration and after 12-24 months. Results: All treated teeth showed resolution of signs and symptoms shortly after treatment with the different medicaments. However, signs and symptoms returned a few months after initial treatment in clinical cases treated with MC-DAP. All successfully treated teeth examined after 12-24 months were free of signs and symptoms, but vitality was not achieved. Conclusion: Low concentration antibiotic gel containing triple antibiotic paste (MC-TAP) can be successfully used for endodontic regeneration procedures.

13.
Exp Neurol ; 358: 114220, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36064003

RESUMO

Perineuronal nets (PNNs) are a specialized extracellular matrix that have been extensively studied in the brain. Cortical PNNs are implicated in synaptic stabilization, plasticity inhibition, neuroprotection, and ionic buffering. However, the role of spinal PNNs, mainly found around motoneurons, is still unclear. Thus, the goal of this study is to elucidate the role of spinal PNNs on motor function and plasticity in both intact and spinal cord injured mice. We used transgenic mice lacking the cartilage link protein 1 (Crtl1 KO mice), which is implicated in PNN assembly. Crtl1 KO mice showed disorganized PNNs with an altered proportion of their components in both motor cortex and spinal cord. Behavioral and electrophysiological tests revealed motor impairments and hyperexcitability of spinal reflexes in Crtl1 KO compared to WT mice. These functional outcomes were accompanied by an increase in excitatory synapses around spinal motoneurons. Moreover, following spinal lesions of the corticospinal tract, Crtl1 KO mice showed increased contralateral sprouting compared to WT mice. Altogether, the lack of Crtl1 generates aberrant PNNs that alter excitatory synapses and change the physiological properties of motoneurons, overall altering spinal circuits and producing motor impairment. This disorganization generates a permissive scenario for contralateral axons to sprout after injury.


Assuntos
Matriz Extracelular , Córtex Motor , Animais , Matriz Extracelular/metabolismo , Camundongos , Camundongos Transgênicos , Plasticidade Neuronal/fisiologia , Tratos Piramidais , Sinapses
14.
Food Chem ; 347: 129023, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33484959

RESUMO

This study developed a novel surface-enhanced Raman spectroscopy (SERS) method coupled with cellulose nanofiber (CNF)-based SERS wipers that were fabricated on quartz papers coated with a mixture of silver nanoparticle (AgNP) and gold nanostar (AuNS). A "drop-wipe-test" protocol was developed for rapid detection of pesticide residues in vegetables by SERS. Tremendously enhanced Raman scattering signals were obtained from the quartz/CNF/mixture (AgNP + AuNS) substrate, which were much higher than the paper/mixture (AgNP + AuNS) substrate. This method was used to detect ferbam on kale leaves within a few minutes and the detection limit was 50 µg/kg based on the PLS models (R2 = 0.89). The enhancement factor of the SERS substrate was calculated to be ~ 104 with satisfactory reproducibility. Satisfactory SERS performance could be achieved within 1-month storage period. These results demonstrate that this CNF-based SERS/wiper method is a practical approach for rapid detection of chemical contaminants in fresh produce.


Assuntos
Brassica/química , Dimetilditiocarbamato/análise , Nanopartículas Metálicas/química , Nanofibras/química , Análise Espectral Raman/métodos , Celulose/química , Ouro/química , Resíduos de Praguicidas/análise , Reprodutibilidade dos Testes , Prata/química
15.
J Neurophysiol ; 104(6): 2975-84, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20861436

RESUMO

Following spinal cord injury (SCI) neurons caudal to the injury are capable of rhythmic locomotor-related activity that can form the basis for substantial functional recovery of stepping despite the loss of crucial brain stem-derived neuromodulators like serotonin (5-HT). Here we investigated the contribution of constitutive 5-HT(2) receptor activity (activity in the absence of 5-HT) to locomotion after SCI. We used a staggered hemisection injury model in rats to study this because these rats showed a robust recovery of locomotor function and yet a loss of most descending axons. Immunolabeling for 5-HT showed little remaining 5-HT below the injury, and locomotor ability was not correlated with the amount of residual 5-HT. Furthermore, blocking 5-HT(2) receptors with an intrathecal (IT) application of the neutral antagonist SB242084 did not affect locomotion (locomotor score and kinematics were unaffected), further indicating that residual 5-HT below the injury did not contribute to generation of locomotion. As a positive control, we found that the same application of SB242084 completely antagonized the muscle activity induced by exogenous application of the 5-HT(2) receptor agonists alpha-methyl-5-HT (IT). In contrast, blocking constitutive 5-HT(2) receptor activity with the potent inverse agonist SB206553 (IT) severely impaired stepping as assessed with kinematic recordings, eliminating most hindlimb weight support and overall reducing the locomotor score in both hind legs. However, even in the most severely impaired animals, rhythmic sweeping movements of the hindlimb feet were still visible during forelimb locomotion, suggesting that SB206553 did not completely eliminate locomotor drive to the motoneurons or motoneuron excitability. The same application of SB206553 had no affect on stepping in normal rats. Thus while normal rats can compensate for loss of 5-HT(2) receptor activity, after severe spinal cord injury rats require constitutive activity in these 5-HT(2) receptors to produce locomotion.


Assuntos
Transtornos Neurológicos da Marcha/fisiopatologia , Locomoção/fisiologia , Receptores 5-HT2 de Serotonina/fisiologia , Serotonina/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Aminopiridinas/farmacologia , Animais , Cordotomia , Eletromiografia , Feminino , Transtornos Neurológicos da Marcha/tratamento farmacológico , Transtornos Neurológicos da Marcha/etiologia , Membro Posterior/fisiopatologia , Indóis/farmacologia , Injeções Espinhais , Locomoção/efeitos dos fármacos , Hipotonia Muscular/etiologia , Piridinas/farmacologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Serotonina/análogos & derivados , Serotonina/farmacologia , Serotonina/uso terapêutico , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Agonistas do Receptor de Serotonina/uso terapêutico , Traumatismos da Medula Espinal/complicações , Cauda/fisiopatologia
16.
BJU Int ; 105(1): 8-13, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19889065

RESUMO

Research into the hypoxic tumour microenvironment is accelerating and the reversal of hypoxia is increasingly being suggested as a mechanism for improving cancer treatment. Recent studies have suggested that hypoxia is also a feature in prostate cancer and is associated with a poor prognosis. Hypoxia has been shown to cause radio-resistance and hence hamper one of the major treatments for prostate cancer. However, unlike other solid tumours, such as cervical and head-and-neck cancer, there are inconsistencies and unanswered questions about the relevance of hypoxia in prostate cancer. This review outlines the role of low-oxygen conditions in prostate cancer and the areas where further studies are required.


Assuntos
Hipóxia Celular , Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias da Próstata/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proliferação de Células , Sobrevivência Celular , Humanos , Masculino , Neoplasias da Próstata/irrigação sanguínea , Neoplasias da Próstata/terapia
17.
Exp Neurol ; 333: 113410, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32735871

RESUMO

This review is based on a lecture presented at the Craig H. Neilsen Foundation sponsored Spinal Cord Injury Training Program at Ohio State University. We discuss the advantages and challenges of injury models in rodents and theory relation to various behavioral outcome measures. We offer strategies and advice on experimental design, behavioral testing, and on the challenges, one will encounter with animal testing. This review is designed to guide those entering the field of spinal cord injury and/or involved with in vivo animal testing.


Assuntos
Comportamento Animal , Traumatismos da Medula Espinal/psicologia , Animais , Modelos Animais de Doenças , Humanos , Modelos Animais , Recuperação de Função Fisiológica
18.
Nat Commun ; 11(1): 84, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31901081

RESUMO

Areas of a junction between two types of epithelia are known to be cancer-prone in many organ systems. However, mechanisms for preferential malignant transformation at the junction areas remain insufficiently elucidated. Here we report that inactivation of tumor suppressor genes Trp53 and Rb1 in the gastric squamous-columnar junction (SCJ) epithelium results in preferential formation of metastatic poorly differentiated neoplasms, which are similar to human gastroesophageal carcinoma. Unlike transformation-resistant antral cells, SCJ cells contain a highly proliferative pool of immature Lgr5-CD44+ cells, which are prone to transformation in organoid assays, comprise early dysplastic lesions, and constitute up to 30% of all neoplastic cells. CD44 ligand osteopontin (OPN) is preferentially expressed in and promotes organoid formation ability and transformation of the SCJ glandular epithelium. OPN and CD44 overexpression correlate with the worst prognosis of human gastroesophageal carcinoma. Thus, detection and selective targeting of the active OPN-CD44 pathway may have direct clinical relevance.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Junção Esofagogástrica/metabolismo , Receptores de Hialuronatos/metabolismo , Osteopontina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Neoplasias Gástricas/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica , Estudos de Coortes , Junção Esofagogástrica/patologia , Feminino , Humanos , Receptores de Hialuronatos/genética , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Osteopontina/genética , Receptores Acoplados a Proteínas G/genética , Proteína do Retinoblastoma/genética , Proteína do Retinoblastoma/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
19.
Int J Cancer ; 124(1): 223-32, 2009 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18924134

RESUMO

Nitric oxide-donating non-steroidal anti-inflammatory drugs are safer than traditional NSAIDs and inhibit the growth of prostate cancer cells with greater potency than NSAIDs. In vivo, prostate cancer deposits are found in a hypoxic environment which induces resistance to chemotherapy. The aim of this study was to assess the effects and mechanism of action of a NO-NSAID called NO-sulindac on the PC-3 prostate cancer cell line under hypoxic conditions. NO-sulindac was found to have pro-apoptotic, cytotoxic, and anti-invasive effect on PC-3 cells under normoxia and hypoxia. NO-sulindac was significantly more cytotoxic than sulindac at all oxygen levels. The sulindac/linker and NO-releasing subunits both contributed to the cytotoxic effects of NO-sulindac. Resistance of PC-3 cells to NO-sulindac was induced as the oxygen concentration declined. Hypoxia-induced chemoresistance was reversed by knocking-down hypoxia-inducible factor-1alpha (HIF-1alpha) mRNA using RNAi. Nuclear HIF-1alpha levels were upregulated at 0.2% oxygen but reduced by treatment with NO-sulindac, as was Akt phosphorylation. NO-sulindac treatment of hypoxic PC-3 cells transfected with a reporter construct, downregulated activation of the hypoxia response element (HRE) promoter. Co-transfection of PC-3 cells with the HRE promoter reporter construct and myr-Akt (constitutively active Akt) plasmids reversed the NO-sulindac induced reduction in HRE activation. Real-time polymerase chain reaction analysis of hypoxic, NO-sulindac treated PC-3 cells showed downregulation of lysyl oxidase and carbonic anhydrase IX mRNA expression. Collectively, these novel findings demonstrate that NO-sulindac directly inhibits the hypoxia response of PC-3 prostate cancer cells by inhibiting HIF-1alpha translation via the Akt signalling pathway. The ability of NO-sulindac to inhibit tumour adaption to hypoxia has considerable relevance to the future management of prostate cancer with the same cellular properties as PC-3.


Assuntos
Regulação Neoplásica da Expressão Gênica , Hipóxia , Neoplasias da Próstata/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sulindaco/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Interferência de RNA , Elementos de Resposta , Transdução de Sinais
20.
Spinal Cord ; 47(10): 727-32, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19255587

RESUMO

STUDY DESIGN: Additional examination. In this study, we report changes in bladder function after a combined treatment that was designed to study axonal regeneration after complete spinal cord injury (SCI) in rats. OBJECTIVES: To report effects on bladder function following the administration of a combined treatment for complete SCI. SETTING: University of Alberta, Faculty of Rehabilitation Medicine, Edmonton, Canada. METHODS: Eight rats received Schwann cells in Matrigel-filled guidance channels, olfactory ensheathing glia and chondroitinase ABC at the lesion site following complete thoracic SCI. Controls (n=7) received Matrigel only. Daily bladder examinations were performed. Analysis of bladder size, wall thickness, actin and collagen type III was performed after 14 weeks. RESULTS: Following SCI, both groups regained bladder voiding after 3 weeks. However, 2 weeks later, incontinence was observed in all untreated rats and two treated rats. Post-mortem examination of bladders revealed enlarged bladder sizes. Thicker bladder walls were found in untreated rats, which were composed of disorganized bundles of smooth muscle fibers surrounded by high amounts of collagen (type III). CONCLUSION: We show that the combined treatment prevents collagen deposition in bladder walls and maintains the rat's ability to void efficiently. Although the mechanism responsible for this improvement is unclear, our study shows that the present combinatory therapy can influence bladder function, thus expanding their utility as a broad reparative approach for SCI.


Assuntos
Condroitinases e Condroitina Liases/farmacologia , Cicatriz/tratamento farmacológico , Regeneração Nervosa/efeitos dos fármacos , Traumatismos da Medula Espinal/terapia , Transplante de Tecidos/métodos , Bexiga Urinaria Neurogênica/terapia , Animais , Condroitina ABC Liase/farmacologia , Condroitina ABC Liase/uso terapêutico , Condroitinases e Condroitina Liases/uso terapêutico , Cicatriz/fisiopatologia , Cicatriz/prevenção & controle , Colágeno/metabolismo , Colágeno/farmacologia , Colágeno/uso terapêutico , Modelos Animais de Doenças , Combinação de Medicamentos , Feminino , Laminina/farmacologia , Laminina/uso terapêutico , Músculo Liso/metabolismo , Músculo Liso/patologia , Regeneração Nervosa/fisiologia , Neuroglia/citologia , Neuroglia/fisiologia , Neuroglia/transplante , Bulbo Olfatório/citologia , Bulbo Olfatório/transplante , Proteoglicanas/farmacologia , Proteoglicanas/uso terapêutico , Ratos , Ratos Endogâmicos F344 , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Células de Schwann/citologia , Células de Schwann/fisiologia , Células de Schwann/transplante , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/fisiopatologia , Resultado do Tratamento , Bexiga Urinária/inervação , Bexiga Urinária/patologia , Bexiga Urinária/fisiopatologia , Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinaria Neurogênica/prevenção & controle
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