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1.
J Dent Educ ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741343

RESUMO

AIMS: In the literature, it is still unclear if the decisions for selecting the type of implant crown-retaining system are based on scientific-based research or if the Universities' choices, Implant marketing trends, or finances could have a major influence on the private dentists' decisions. OBJECTIVES: Therefore, this study aimed to evaluate the crown-retaining system (cement- or screw-retained) used in dental schools and private dental practices. METHODS: A 13-item questionnaire was sent to Canadian dental schools (n = 10) and dental offices in London (n = 298), Canada. The questionnaire included demographic questions and questions to reveal the dentists' perspectives on prosthetic implant treatment between the two-retaining systems. Results were analyzed using descriptive statistics and multinomial logistic regression (p = 0.05). RESULTS: Twenty-four private dentists and five dental schools responded to the survey - 62.5% of private practitioners and 60% of universities reported using both systems. A trend was observed in using screw-retained systems by dentists who graduated 5-10 years ago. Straumann, Astra, and Nobel Biocare were the private practices and dental schools' preferred implant systems. The use of platform switching for all cases was selected by 54.2% of the private practitioners and 40% of the dental schools. Resin cement was the private practice's preferred cementation method; the dental schools used glass ionomer and zinc phosphate cement. The multinomial logistic regressions showed no statistical difference between the crown-retaining system chosen and the decision factors. The laboratory technician's recommendations and cost influenced the decision-making process for private dentists. For the universities, perio-restorative outcome, implant position, survival rates, institute preferences, and evidence-based research influenced the crown-retaining system's decision-making process.  CONCLUSION: The Canadian dental schools and private practice reported using both screw- and cement-retaining systems. However, there was a difference in the selection criteria as the universities showed a tendency towards a more research-based approach in their decision, while for the private practices, the technicians' recommendations and cost played a major role in the decision process. It was noted that the implant systems preconized by the Universities were observed to be used in private practices.

2.
bioRxiv ; 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38405820

RESUMO

Background: We identified a novel SCN5A variant, E171Q, in a neonate with very frequent ectopy and reduced ejection fraction which normalized after arrhythmia suppression by flecainide. This clinical picture is consistent with multifocal ectopic Purkinje-related premature contractions (MEPPC). Most previous reports of MEPPC have implicated SCN5A variants such as R222Q that neutralize positive charges in the S4 voltage sensor helix of the channel protein NaV1.5 and generate a gating pore current. Methods and Results: E171 is a highly conserved negatively-charged residue located in the S2 transmembrane helix of NaV1.5 domain I. E171 is a key component of the Gating Charge Transfer Center, a region thought to be critical for normal movement of the S4 voltage sensor helix. We used heterologous expression, CRISPR-edited induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), and molecular dynamics simulations to demonstrate that E171Q generates a gating pore current, which was suppressed by a low concentration of flecainide (IC50 = 0.71±0.07 µM). R222Q shifts voltage dependence of activation and inactivation in a negative direction but we observed positive shifts with E171Q. E171Q iPSC-CMs demonstrated abnormal spontaneous activity and prolonged action potentials. Molecular dynamics simulations revealed that both R222Q and E171Q proteins generate a water-filled permeation pathway that underlies generation of the gating pore current. Conclusion: Previously identified MEPPC-associated variants that create gating pore currents are located in positively-charged residues in the S4 voltage sensor and generate negative shifts in the voltage dependence of activation and inactivation. We demonstrate that neutralizing a negatively charged S2 helix residue in the Gating Charge Transfer Center generates positive shifts but also create a gating pore pathway. These findings implicate the gating pore pathway as the primary functional and structural determinant of MEPPC and widen the spectrum of variants that are associated with gating pore-related disease in voltage-gated ion channels.

3.
Egypt Heart J ; 75(1): 63, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37466800

RESUMO

BACKGROUND: Many patients would require repeated ablation procedures owing to recurrent atrial fibrillation with its associated symptoms. Identifying those who are at risk of recurrent AF could assist us to develop preventive strategies and to properly select those who will benefit more from catheter ablation. Our aim is to study the role of preprocedural serum level of certain biomarkers in the prediction of AF recurrence after catheter ablation. RESULTS: The present study included 117 patients: 26 patients with persistent and 91 patients with paroxysmal AF. Blood samples for estimation of serum levels of studied cytokines were obtained prior to the procedure. Pulmonary vein isolation was performed in all patients through point-by point radiofrequency ablation guided by 3D electroanatomical mapping system. Patients were followed for 12 months for AF recurrence. Forty-one (35%) patients developed AF recurrence. Those patients were significantly older, had significantly higher BMI, lower ejection fraction, and wider maximal left atrial diameter (LAD). Serum hs-CRP, IL-6, TNF-α, visfatin, and adiponectin levels were significantly higher compared to those who did not develop AF recurrence. Correlation analysis showed positive correlations between the incidence of RAF and patients' age, BMI, and maximum LAD and elevated cytokine levels and maximal LAD showed significant correlations with the type of AF and elevated serum TNF-α, visfatin, and adiponectin. Statistical analyses defined elevated serum levels of TNF-α, visfatin, and adiponectin as positive predictors for RAF, and automatic linear modeling analysis showed that elevated serum visfatin, TNF-α, and adiponectin can predict RAF by accuracy rates of 50%, 34%, and 16%, respectively. CONCLUSIONS: RAF is most probably an outcome of the interplay between patients' clinical data, obesity, and inflammation. Pre-procedural estimation of serum levels of visfatin and TNF-α might determine patients with probability for RAF.

4.
Int J Mol Sci ; 24(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37298433

RESUMO

Pulmonary fibrosis (PF) is a life-threatening disorder that severely disrupts normal lung architecture and function, resulting in severe respiratory failure and death. It has no definite treatment. Empagliflozin (EMPA), a sodium-glucose cotransporter 2 (SGLT2) inhibitor, has protective potential in PF. However, the mechanisms underlying these effects require further elucidation. Therefore, this study aimed to evaluate the ameliorative effect of EMPA against bleomycin (BLM)-induced PF and the potential mechanisms. Twenty-four male Wister rats were randomly divided into four groups: control, BLM treated, EMPA treated, and EMPA+BLM treated. EMPA significantly improved the histopathological injuries illustrated by both hematoxylin and eosin and Masson's trichrome-stained lung tissue sections, as confirmed by electron microscopic examination. It significantly reduced the lung index, hydroxyproline content, and transforming growth factor ß1 levels in the BLM rat model. It had an anti-inflammatory effect, as evidenced by a decrease in the inflammatory cytokines' tumor necrosis factor alpha and high mobility group box 1, inflammatory cell infiltration into the bronchoalveolar lavage fluid, and the CD68 immunoreaction. Furthermore, EMPA mitigated oxidative stress, DNA fragmentation, ferroptosis, and endoplasmic reticulum stress, as evidenced by the up-regulation of nuclear factor erythroid 2-related factor expression, heme oxygenase-1 activity, glutathione peroxidase 4 levels, and a decrease in C/EBP homologous protein levels. This protective potential could be explained on the basis of autophagy induction via up-regulating lung sestrin2 expression and the LC3 II immunoreaction observed in this study. Our findings indicated that EMPA protected against BLM-induced PF-associated cellular stress by enhancing autophagy and modulating sestrin2/adenosine monophosphate-activated protein kinase/nuclear factor erythroid 2-related factor 2/heme oxygenase 1 signaling.


Assuntos
Ferroptose , Fibrose Pulmonar , Ratos , Masculino , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Bleomicina/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Ratos Wistar , Pulmão/patologia
5.
PLoS One ; 18(5): e0281977, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37159454

RESUMO

BACKGROUND: Brugada (BrS) and early repolarization syndromes (ERS), the so-called J wave syndromes (JWS), are associated with life-threatening ventricular arrhythmias. Pharmacologic approaches to therapy are currently limited. In this study, we examine the effects of ARumenamide-787 (AR-787) to suppress the electrocardiographic and arrhythmic manifestations of JWS and hypothermia. METHODS: We studied the effects of AR-787 on INa and IKr in HEK-293 cells stably expressing the α- and ß1-subunits of the cardiac (NaV1.5) sodium channel and hERG channel, respectively. In addition, we studied its effect on Ito, INa and ICa in dissociated canine ventricular myocytes along with action potentials and ECG from coronary-perfused right (RV) and left (LV) ventricular wedge preparations. The Ito agonist, NS5806 (5-10 µM), ICa blocker, verapamil (2.5 µM), and INa blocker, ajmaline (2.5 µM), were used to mimic the genetic defects associated with JWS and to induce the electrocardiographic and arrhythmic manifestations of JWS (prominent J waves/ST segment elevation, phase 2 reentry and polymorphic VT/VF) in canine ventricular wedge preparations. RESULTS: AR-787 (1, 10 and 50 µM) exerted pleiotropic effects on cardiac ion channels. The predominant effect was inhibition of the transient outward current (Ito) and enhancement of the sodium channel current (INa), with lesser effects to inhibit IKr and augment calcium channel current (ICa). AR-787 diminished the electrocardiographic J wave and prevented and/or suppressed all arrhythmic activity in canine RV and LV experimental models of BrS, ERS and hypothermia. CONCLUSIONS: Our findings point to AR-787 as promising candidate for the pharmacologic treatment of JWS and hypothermia.


Assuntos
Hipotermia , Humanos , Animais , Cães , Células HEK293 , Síndrome , Antiarrítmicos/farmacologia , Antiarrítmicos/uso terapêutico , Arritmias Cardíacas/tratamento farmacológico , Miócitos Cardíacos
6.
J Clin Med ; 12(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36902652

RESUMO

Background: Children with chronic kidney disease (CKD), particularly those who require hemodialysis (HD), are at high risk of hepatitis B virus (HBV) infection. The HBV vaccine non-/hypo-response rate among HD children remains high, and it is critical to investigate the influencing factors and their linkages. The aim of this study was to identify the pattern of HB vaccination response in HD children and to analyze the interference of various clinical and biomedical factors with the immunological response to HB vaccination. Methods: This cross-sectional study included 74 children on maintenance hemodialysis, aged between 3 and 18 years. These children were subjected to complete clinical examination and laboratory investigations. Results: Out of a total of 74 children with HD, 25 (33.8%) were positive for the HCV antibody. Regarding the immunological response to hepatitis B vaccine, 70% were non-/hypo-responders (≤100 IU/mL) and only 30% mounted a high-level response (more than 100 IU/mL). There was a significant relation between non-/hypo-response and sex, dialysis duration, and HCV infection. Being on dialysis for more than 5 years and being HCV Ab-positive were independent variables for non-/hypo-response to HB vaccine. Conclusions: Children with CKD on regular HD have poor seroconversion rates in response to the HBV vaccine, which were influenced by dialysis duration and HCV infection.

7.
Clin Rheumatol ; 41(11): 3391-3399, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35861930

RESUMO

OBJECTIVES: Assessment of serum levels of IL-23 in PsA patients and its correlation with depression, anxiety, and disease activity. METHODS: Eighty psoriatic arthritis (PsA) patients and eighty healthy volunteers matched for age and gender were included in this observational case-control study. All participants suspected to detailed history, clinical assessment, PsA activity using Disease Activity Index for Psoriatic Arthritis (DAPSA) score, the severity and extent of psoriasis was assessed by the Psoriasis Area and Severity Index (PASI), and ultrasonographic assessments of the entheses were examined according to the Madrid Sonographic Enthesitis Index (MASEI). Depression and anxiety were assessed by Hospital Anxiety and Depression Scale (HADS). Serum IL-23 was measured and correlated with disease activity, depression, and anxiety. RESULTS: There was no significant difference between patients and controls regarding demographic data. Thirty-six PsA patients (45%) had anxiety and 28 patients (35%) had depression, while in the control group, 16 persons (20%) had anxiety and 12 (15%) had depression, with significant differences between the 2 groups (p < 0.0001). There were significant differences in HADS anxiety and depression scores between patients and controls with significant positive correlations between HADS depression, anxiety scores and IL-23, DAPSA, PASI, and MASEI scores (p < 0.05). IL-23 was positively correlated with DAPSA, PASI, and HADS scores; we observed that interleukin 23, higher DAPSA, and PASI were independently associated with depression and anxiety. CONCLUSION: Serum interleukin-23 levels were elevated in PsA patients and were found to be correlated with depression, anxiety, and disease activity. Key Points • Psoriatic arthritis is a multidimensional disorder with psychiatric drawbacks. • Interleukin-23 is a proinflammatory cytokines that was correlated with depression and anxiety in PsA patients. • Interleukin-23 was correlated with disease activity in PsA. • Depression and anxiety were positively correlated with disease activity in PsA.


Assuntos
Artrite Psoriásica , Psoríase , Ansiedade , Artrite Psoriásica/complicações , Estudos de Casos e Controles , Depressão , Humanos , Interleucina-23 , Índice de Gravidade de Doença
8.
Br J Pharmacol ; 179(24): 5259-5272, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35906756

RESUMO

BACKGROUND: Sepsis, caused by a dysregulated response to infections, can lead to cardiac arrhythmias. However, the mechanisms underlying sepsis-induced inflammation, and how inflammation provokes cardiac arrhythmias, are not well understood. We hypothesized that cannabidiol (CBD) may ameliorate lipopolysaccharide (LPS)-induced cardiotoxicity, via Toll-like receptors (TLR4) and cardiac sodium channels (NaV 1.5). METHODS AND RESULTS: We incubated human immune cells (THP-1 macrophages) with LPS for 24 h, then extracted the THP-1 incubation media. ELISA assays showed that LPS (1 or 5 µg·ml-1 ), in a concentration-dependent manner, or MPLA (TLR4 agonist, 5 µg·ml-1 ) stimulated the THP-1 cells to release inflammatory cytokines (TNF-α and IL-6). Prior incubation (4 h) with CBD (5 µM) or C34 (TLR4 antagonist: 5 µg·ml-1 ) inhibited LPS and MPLA-induced release of both IL-6 and TNF-α. Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) were subsequently incubated for 24 h in the media extracted from THP-1 cells incubated with LPS, MPLA alone, or in combination with CBD or C34. Voltage-clamp experiments showed a right shift in the voltage dependence of NaV 1.5 activation, steady state fast inactivation (SSFI), increased persistent current and prolonged in silico action potential duration in hiSPC-CMs incubated in the LPS or MPLA-THP-1 media. Co-incubation with CBD or C34 rescued the biophysical dysfunction caused by LPS and MPLA. CONCLUSION: Our results suggest that CBD may protect against sepsis-induced inflammation and subsequent arrhythmias through (i) inhibition of the release of inflammatory cytokines, antioxidant and anti-apoptotic effects and/or (ii) a direct effect on NaV 1.5.


Assuntos
Canabidiol , Sepse , Canais de Sódio , Humanos , Anti-Inflamatórios/farmacologia , Canabidiol/farmacologia , Citocinas/metabolismo , Inflamação , Interleucina-6 , Lipopolissacarídeos/farmacologia , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa
9.
Pediatr Pulmonol ; 57(9): 2147-2153, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35621053

RESUMO

BACKGROUND: Ventilator-associated pneumonia (VAP) is one of the most common causes of nosocomial pneumonia in ventilated neonates. Nevertheless, its diagnosis is challenging due to the nonspecific clinical parameters and the lack of sensitive biomarkers. The main objective of this study was to compare soluble triggering receptors expressed on myeloid cells-1 (sTREM-1) and 25-hydroxy vitamin D as early predictors of neonatal VAP. METHODS: This prospective cohort study included 85 ventilated neonates divided into the VAP group (n = 33) and the non-VAP group (n = 52). sTREM-1 levels in the endotracheal aspirate (ETA) and serum 25-hydroxy vitamin D levels were measured on the third and seventh days following mechanical ventilation. The Ethical and Research Committee approved the study at Tanta University Hospitals, Egypt (with the Approval code: 32751/12/18). RESULTS: The sTREM-1 cutoff value of >0.46 and >0.44 ng/ml at 3 and 7 days had a sensitivity of 93.94% and 96.97%, a specificity of 92.31% and 100%, and an area under the receiver operating characteristic curve (AUC) of 0.963 and 0.993, respectively, to predict the development of neonatal VAP. A serum 25-hydroxy vitamin D cutoff value of ≤17.5 ng/ml at 3 and 7 days had a sensitivity of 90.91% and 81.82%, a specificity of 75% and 78.85%, and area under the curve of 0.877 and 0.939, respectively. CONCLUSION: Both sTREM-1 in ETA and serum 25-hydroxy vitamin D could be used as early predictors of neonatal VAP, but sTREM-1 appears more useful.


Assuntos
Pneumonia Associada à Ventilação Mecânica , Biomarcadores , Calcifediol , Humanos , Recém-Nascido , Glicoproteínas de Membrana , Células Mieloides , Pneumonia Associada à Ventilação Mecânica/diagnóstico , Estudos Prospectivos , Receptores Imunológicos , Receptor Gatilho 1 Expresso em Células Mieloides , Vitamina D
10.
Int J Mol Sci ; 23(8)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35456996

RESUMO

Nav1.5 is the pore forming α-subunit of the cardiac voltage-gated sodium channel that initiates cardiac action potential and regulates the human heartbeat. A normal level of Nav1.5 is crucial to cardiac function and health. Over- or under-expression of Nav1.5 can cause various cardiac diseases ranging from short PR intervals to Brugada syndromes. An assay that can directly quantify the protein amount in biological samples would be a priori to accurately diagnose and treat Nav1.5-associated cardiac diseases. Due to its large size (>200 KD), multipass transmembrane domains (24 transmembrane passes), and heavy modifications, Nav1.5 poses special quantitation challenges. To date, only the relative quantities of this protein have been measured in biological samples. Here, we describe the first targeted and mass spectrometry (MS)-based quantitative assay that can provide the copy numbers of Nav1.5 in cells with a well-defined lower limit of quantification (LLOQ) and precision. Applying the developed assay, we successfully quantified transiently expressed Nav1.5 in as few as 1.5 million Chinese hamster ovary (CHO) cells. The obtained quantity was 3 ± 2 fmol on the column and 3 ± 2 × 104 copies/cell. To our knowledge, this is the first absolute quantity of Nav1.5 measured in a biological sample.


Assuntos
Síndrome de Brugada , Canal de Sódio Disparado por Voltagem NAV1.5 , Animais , Células CHO , Cricetinae , Cricetulus , Humanos , Espectrometria de Massas , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo
11.
J Physiol ; 600(12): 2835-2851, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35436004

RESUMO

Acquired and inherited dysfunction in voltage-gated sodium channels underlies a wide range of diseases. In addition to defects in trafficking and expression, sodium channelopathies are caused by dysfunction in one or several gating properties, for instance activation or inactivation. Disruption of channel inactivation leads to increased late sodium current, which is a common defect in seizure disorders, cardiac arrhythmias skeletal muscle myotonia and pain. An increase in late sodium current leads to repetitive action potentials in neurons and skeletal muscles, and prolonged action potential duration in the heart. In this Topical Review, we compare the effects of late sodium current in brain, heart, skeletal muscle and peripheral nerves.


Assuntos
Miotonia , Arritmias Cardíacas , Humanos , Miotonia/metabolismo , Dor , Sódio/metabolismo , Síndrome
12.
Haemophilia ; 28(3): 472-479, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35316553

RESUMO

INTRODUCTION: Haemophilia A (HA) is an x-linked recessive disease due to deficiency of coagulation factor VIII (FVIII). The development of neutralizing antibodies (inhibitors) against infused FVIII is a major concern. B cell activating factor (BAFF) has been implicated in several autoimmune diseases. AIM: We aimed to evaluate the possible association of BAFF rs9514828 gene polymorphism and the risk of the development of FVIII inhibitor in children with severe HA. METHODS: This cohort study was carried out on 100 newly diagnosed boys with severe HA who were never treated before with FVIII concentrate. Assessment of serum levels of BAFF and BAFF rs9514828 genotyping at first diagnosis was performed and the patients were followed up for the completion of a total of 50 exposure days or the development of inhibitors whichever occurred first. The patients were divided as positive or negative according to the presence or absence of inhibitors. RESULTS: The risk allele for BAFF rs9514828 (T) was significantly more frequent in the inhibitor positive patients than the inhibitor negative patients (P = .003). In addition, CT+TT genotypes were associated with increased risk of FVIII inhibitor development. Receiver operating characteristics (ROC) analysis showed that BAFF levels could predict the development of FVIII inhibitors at a cut-off value of ≥ .92 with a sensitivity of 85.9% and a specificity of 80.2%. CONCLUSION: BAFF rs9514828 gene polymorphism could be independent risk factor and elevated BAFF levels might be useful prognostic marker for the development of FVIII inhibitor in newly diagnosed children with severe HA.


Assuntos
Fator Ativador de Células B , Fator VIII , Hemofilia A , Hemostáticos , Alelos , Fator Ativador de Células B/genética , Criança , Estudos de Coortes , Fator VIII/antagonistas & inibidores , Fator VIII/genética , Hemofilia A/tratamento farmacológico , Hemofilia A/genética , Humanos , Masculino , Polimorfismo de Nucleotídeo Único
13.
Appl Opt ; 60(28): 8851-8857, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34613111

RESUMO

Phenantrenequinone doped poly(methyl-methacrylate) (PQ:PMMA) is a holographic substrate that can be used for angle or wavelength multiplexed Bragg gratings. However, efficient writings can be done only using a high-power, long-coherence volume laser over a limited wavelength range. This constraint makes it difficult to write gratings that would diffract several different read wavelengths into a single direction. We describe the rules for writing such gratings, taking into account the differences in the mean index seen by the write and read wavelengths. We further demonstrate the use of such a transmission hologram for wavelength-division multiplexing in a free-space optical communication system.

14.
Front Pharmacol ; 12: 668657, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995099

RESUMO

Background: Cardiovascular anomalies are predisposing factors for diabetes-induced morbidity and mortality. Recently, we showed that high glucose induces changes in the biophysical properties of the cardiac voltage-gated sodium channel (Nav1.5) that could be strongly correlated to diabetes-induced arrhythmia. However, the mechanisms underlying hyperglycemia-induced inflammation, and how inflammation provokes cardiac arrhythmia, are not well understood. We hypothesized that inflammation could mediate the high glucose-induced biophyscial changes on Nav1.5 through protein phosphorylation by protein kinases A and C. We also hypothesized that this signaling pathway is, at least partly, involved in the cardiprotective effects of cannabidiol (CBD) and 17ß-estradiol (E2). Methods and Results: To test these ideas, we used Chinese hamster ovarian (CHO) cells transiently co-transfected with cDNA encoding human Nav1.5 α-subunit under control, a cocktail of inflammatory mediators or 100 mM glucose conditions (for 24 h). We used electrophysiological experiments and action potential modeling. Inflammatory mediators, similar to 100 mM glucose, right shifted the voltage dependence of conductance and steady-state fast inactivation and increased persistent current leading to computational prolongation of action potential (hyperexcitability) which could result in long QT3 arrhythmia. We also used human iCell cardiomyocytes derived from inducible pluripotent stem cells (iPSC-CMs) as a physiologically relevant system, and they replicated the effects produced by inflammatory mediators observed in CHO cells. In addition, activators of PK-A or PK-C replicated the inflammation-induced gating changes of Nav1.5. Inhibitors of PK-A or PK-C, CBD or E2 mitigated all the potentially deleterious effects provoked by high glucose/inflammation. Conclusion: These findings suggest that PK-A and PK-C may mediate the anti-inflammatory effects of CBD and E2 against high glucose-induced arrhythmia. CBD, via Nav1.5, may be a cardioprotective therapeutic approach in diabetic postmenopausal population.

15.
Clin Exp Pharmacol Physiol ; 48(9): 1261-1270, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34042216

RESUMO

Evidence suggests that immunosuppressant therapies protect against harmful effects of endotoxaemia. In this study, we tested whether calcineurin-dependent (cyclosporine/tacrolimus) and -independent (sirolimus) immunosuppressants variably influence nephrotoxicity induced by endotoxaemia and whether this interaction is modulated by testosterone. We investigated the effects of immunosuppressants on renal histopathological, biochemical and inflammatory profiles in endotoxic male rats and the role of androgenic state in the interaction. Six-hour treatment of rats with lipopolysaccharide (LPS, 3 mg/kg) increased (i) serum urea/creatinine, (ii) width of proximal/distal tubules, (iii) tubular degeneration and vacuolation, (iv) Western protein expressions of renal toll-like receptor 4, monocyte chemoattractant protein-1, and NADPH oxidase-2, and (v) serum tumour necrosis factor-α and myeloperoxidase. These endotoxic manifestations were intensified and eliminated upon concurrent exposure to cyclosporine and sirolimus, respectively. The cyclosporine actions appear to be a class rather than a drug effect because similar exacerbation of LPS nephrotoxicity was observed in rats treated with tacrolimus, another calcineurin inhibitor (CNI). Moreover, the deteriorated renal outcomes in LPS/tacrolimus-treated rats were reduced after castration or androgen receptor blockade by flutamide. The data suggest opposite effects for calcineurin-dependent (exaggeration) and -independent immunosuppressants (amelioration) on renal defects of endotoxaemia and implicate androgenic pathways in the worsened endotoxic renal profile induced by CNIs.


Assuntos
Imunossupressores
16.
J Gen Physiol ; 153(5)2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33836525

RESUMO

Cannabidiol (CBD) is the primary nonpsychotropic phytocannabinoid found in Cannabis sativa, which has been proposed to be therapeutic against many conditions, including muscle spasms. Among its putative targets are voltage-gated sodium channels (Navs), which have been implicated in many conditions. We investigated the effects of CBD on Nav1.4, the skeletal muscle Nav subtype. We explored direct effects, involving physical block of the Nav pore, as well as indirect effects, involving modulation of membrane elasticity that contributes to Nav inhibition. MD simulations revealed CBD's localization inside the membrane and effects on bilayer properties. Nuclear magnetic resonance (NMR) confirmed these results, showing CBD localizing below membrane headgroups. To determine the functional implications of these findings, we used a gramicidin-based fluorescence assay to show that CBD alters membrane elasticity or thickness, which could alter Nav function through bilayer-mediated regulation. Site-directed mutagenesis in the vicinity of the Nav1.4 pore revealed that removing the local anesthetic binding site with F1586A reduces the block of INa by CBD. Altering the fenestrations in the bilayer-spanning domain with Nav1.4-WWWW blocked CBD access from the membrane into the Nav1.4 pore (as judged by MD). The stabilization of inactivation, however, persisted in WWWW, which we ascribe to CBD-induced changes in membrane elasticity. To investigate the potential therapeutic value of CBD against Nav1.4 channelopathies, we used a pathogenic Nav1.4 variant, P1158S, which causes myotonia and periodic paralysis. CBD reduces excitability in both wild-type and the P1158S variant. Our in vitro and in silico results suggest that CBD may have therapeutic value against Nav1.4 hyperexcitability.


Assuntos
Canabidiol , Canalopatias , Canal de Sódio Disparado por Voltagem NAV1.4 , Canais de Sódio Disparados por Voltagem , Canabidiol/farmacologia , Elasticidade , Humanos , Músculo Esquelético , Canal de Sódio Disparado por Voltagem NAV1.4/metabolismo
17.
Expert Rev Clin Immunol ; 17(5): 539-544, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33734916

RESUMO

Background: Psoriatic arthritis is a chronic inflammatory condition. It impacts patients both physically and psychologically. Fatigue may be an early symptom of PsA, which impairs quality of life.Objectives: To assess serum IL-17, fatigue, quality of life and function impairment in PsA patients and to correlate them with clinical disease activity.Methods: 80 consecutive PsA patients were included. Fatigue assessed by Functional Assessment of Chronic Illness Therapy-Fatigue. Quality of life assessed by Psoriatic Arthritis Quality of Life. Functional capacity assessed by health assessment questionnaire. Disease activity assessed by Disease Activity in Psoriatic Arthritis. Serum IL-17 measured by ELISA.Results: There was significant difference in FACIT-F, PsAQOL, and HAQ (p<0.001) in different disease activity subgroups. There was statistically significant correlation of disease duration with disease activity, fatigue, reduced function capacity, and quality of life impairment (p≤0.05), while no correlation with the patients' age. There was statistically significant correlation between FACIT-F, PsAQOL, HAQ, and DAPSA scores (p<0.001). Serum IL-17 was significantly correlated with clinical parameters of disease activity, fatigue, function, and quality of life impairment (p≤0.05).Conclusion: Fatigue is a common clinical symptom in psoriatic arthritis patients. It is significantly associated with IL17, quality of life, functional impairment and disease activity.


Assuntos
Artrite Psoriásica , Qualidade de Vida , Artrite Psoriásica/diagnóstico , Fadiga/diagnóstico , Humanos , Interleucina-17 , Índice de Gravidade de Doença , Inquéritos e Questionários
18.
J Blood Med ; 12: 147-156, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33758569

RESUMO

BACKGROUND: CD105 (Endoglin) is a receptor of the transforming growth factor-Beta (TGF- ß) superfamily. It is expressed in angiogenic endothelial cells and is considered a powerful marker of angiogenesis and a potential main player in the pathogenesis of vascular diseases as well as tumor progression. CD105 expression was correlated with poor prognosis in many types of solid malignancies, however, its influence on hematological neoplasms is still an area of interest. PURPOSE: To assess the flow-cytometric expression of CD105 in childhood B-acute lymphoblastic leukemia (B-ALL) and its relation to disease response after the induction chemotherapy. SUBJECTS AND METHODS: Eighty children newly diagnosed with B-ALL were screened for flow-cytometric expression of CD105 at time of diagnosis, then they were followed up to detect their response to induction therapy. RESULTS: CD105 was expressed in 41.2% of B-ALL patients. Higher expression of CD105 was observed in high and very high-risk groups. The multivariate analysis considered CD105 positivity as an independent prognostic marker for response to induction therapy. Values higher than 2.5 Specific fluorescence indices (SFIs) and 35% expression were sensitive predictors to induction failure. CONCLUSION: CD105 can be considered as a potential prognostic marker for the detection of response to induction therapy in childhood B-ALL, and it can serve to optimize treatment decisions.

19.
Toxicol Lett ; 335: 28-36, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33091562

RESUMO

Endotoxic manifestations are diminished in female populations due to immune boosting actions of sex steroids. Considering that tobacco constituents including nicotine inhibit estrogen synthesis, we tested the hypothesis that nicotine exposure unveils cardiovascular anomalies of endotoxemia in female rats. Studies were undertaken in conscious female rats treated with i.v. lipopolysaccharide (LPS, 10 mg/kg) in absence and presence of nicotine. In contrast to no effects for LPS when used alone, dose-related decreases in blood pressure (BP) and serum estrogen were noted in endotoxic rats treated consequently with nicotine (25, 50, or 100 µg/kg i.v.). Signs of cardiac autonomic dysfunction appeared in LPS/nicotine-treated rats such as (i) decreased time-domain indices of heart rate variability (HRV), e.g. standard deviation of R-R intervals (SDNN) and root mean square of successive differences in R-R interval durations (rMSSD), and (ii) reduced total power of the frequency spectrum and shifted cardiac sympathovagal balance toward sympathetic dominance. Nicotine reversed the LPS-evoked modest rises in serum TNFα and IL-1ß while had no effect on associated arterial baroreflex dysfunction, inferring no roles for inflammation or baroreflexes in LPS-nicotine interaction. Estrogen or aminoguanidine (iNOS inhibitor), but not pentoxifylline (TNFα inhibitor), abolished LPS/nicotine hypotension. Together, nicotine acts probably via reducing estrogen availability to uncover nitric oxide-dependent hypotension and autonomic dysregulation in endotoxic female rats.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Endotoxemia/induzido quimicamente , Estrogênios/sangue , Frequência Cardíaca/efeitos dos fármacos , Coração/efeitos dos fármacos , Nicotina/toxicidade , Óxido Nítrico/sangue , Animais , Sistema Nervoso Autônomo/efeitos dos fármacos , Barorreflexo/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Endotoxemia/sangue , Endotoxemia/imunologia , Endotoxemia/fisiopatologia , Endotoxinas/toxicidade , Feminino , Coração/inervação , Interleucina-1beta/sangue , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/sangue
20.
Mar Drugs ; 18(5)2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32380771

RESUMO

Liquid chromatography coupled with high resolution mass spectrometry (LC-HRESMS)-assisted metabolomic profiling of two sponge-associated actinomycetes, Micromonospora sp. UR56 and Actinokineospora sp. EG49, revealed that the co-culture of these two actinomycetes induced the accumulation of metabolites that were not traced in their axenic cultures. Dereplication suggested that phenazine-derived compounds were the main induced metabolites. Hence, following large-scale co-fermentation, the major induced metabolites were isolated and structurally characterized as the already known dimethyl phenazine-1,6-dicarboxylate (1), phenazine-1,6-dicarboxylic acid mono methyl ester (phencomycin; 2), phenazine-1-carboxylic acid (tubermycin; 3), N-(2-hydroxyphenyl)-acetamide (9), and p-anisamide (10). Subsequently, the antibacterial, antibiofilm, and cytotoxic properties of these metabolites (1-3, 9, and 10) were determined in vitro. All the tested compounds except 9 showed high to moderate antibacterial and antibiofilm activities, whereas their cytotoxic effects were modest. Testing against Staphylococcus DNA gyrase-B and pyruvate kinase as possible molecular targets together with binding mode studies showed that compounds 1-3 could exert their bacterial inhibitory activities through the inhibition of both enzymes. Moreover, their structural differences, particularly the substitution at C-1 and C-6, played a crucial role in the determination of their inhibitory spectra and potency. In conclusion, the present study highlighted that microbial co-cultivation is an efficient tool for the discovery of new antimicrobial candidates and indicated phenazines as potential lead compounds for further development as antibiotic scaffold.


Assuntos
Actinobacteria/metabolismo , Antibacterianos/farmacologia , Micromonospora/metabolismo , Poríferos/microbiologia , Inibidores da Topoisomerase II/farmacologia , Actinobacteria/isolamento & purificação , Animais , Antibacterianos/biossíntese , Antibacterianos/química , Antibacterianos/isolamento & purificação , Técnicas Bacteriológicas/métodos , Biofilmes/efeitos dos fármacos , DNA Girase/metabolismo , Ensaios Enzimáticos , Fermentação , Metabolômica/métodos , Testes de Sensibilidade Microbiana , Micromonospora/isolamento & purificação , Conformação Molecular , Simulação de Acoplamento Molecular , Piruvato Quinase/antagonistas & inibidores , Piruvato Quinase/metabolismo , Staphylococcus/efeitos dos fármacos , Staphylococcus/enzimologia , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/química , Inibidores da Topoisomerase II/isolamento & purificação , Inibidores da Topoisomerase II/metabolismo
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