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1.
Int J Mol Sci ; 24(11)2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37298433

RESUMEN

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.


Asunto(s)
Ferroptosis , Fibrosis Pulmonar , Ratas , Masculino , Animales , Fibrosis Pulmonar/inducido químicamente , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/metabolismo , Bleomicina/toxicidad , Factor 2 Relacionado con NF-E2/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Ratas Wistar , Pulmón/patología
2.
J Physiol ; 600(12): 2835-2851, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35436004

RESUMEN

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.


Asunto(s)
Miotonía , Arritmias Cardíacas , Humanos , Miotonía/metabolismo , Dolor , Sodio/metabolismo , Síndrome
3.
Haemophilia ; 28(3): 472-479, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35316553

RESUMEN

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.


Asunto(s)
Factor Activador de Células B , Factor VIII , Hemofilia A , Hemostáticos , Alelos , Factor Activador de Células B/genética , Niño , Estudios de Cohortes , Factor VIII/antagonistas & inhibidores , Factor VIII/genética , Hemofilia A/tratamiento farmacológico , Hemofilia A/genética , Humanos , Masculino , Polimorfismo de Nucleótido Simple
4.
Int J Mol Sci ; 23(8)2022 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-35456996

RESUMEN

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.


Asunto(s)
Síndrome de Brugada , Canal de Sodio Activado por Voltaje NAV1.5 , Animales , Células CHO , Cricetinae , Cricetulus , Humanos , Espectrometría de Masas , Canal de Sodio Activado por Voltaje NAV1.5/genética , Canal de Sodio Activado por Voltaje NAV1.5/metabolismo
5.
Clin Exp Pharmacol Physiol ; 48(9): 1261-1270, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34042216

RESUMEN

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.


Asunto(s)
Inmunosupresores
6.
Appl Opt ; 60(28): 8851-8857, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34613111

RESUMEN

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.

7.
Toxicol Appl Pharmacol ; 393: 114928, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32092384

RESUMEN

The female gender is protected against immunological complications of endotoxemia. Here we investigated whether gonadal hormone depletion by ovariectomy (OVX) uncovers inflammatory and cardiovascular effects of endotoxemia and whether these effects are reversed by hormone replacement therapies. Changes in inflammatory cytokines, blood pressure (BP), left ventricular (LV) function, and cardiac autonomic activity caused by lipopolysaccharide (LPS) in conscious female rats with different hormonal states were determined. In contrast to no effects in sham-operated females, treatment of OVX rats with LPS (i) decreased BP, (ii) increased spectral low-frequency/high-frequency ratio of HRV, denoting enhanced cardiac sympathetic dominance, (iii) attenuated reflex tachycardic responses to sodium nitroprusside, and (iv) increased systolic contractility (dP/dtmax). The developed hypotension was (i) fully eliminated in estrogen (E2)-pretreated OVX rats, (ii) partially counteracted after selective activation of estrogen receptor-α (PPT) or ß (DPN). All estrogenic compounds abrogated LPS enhancement of cardiac sympathetic drive. However, PPT was more successful than E2 or DPN in compromising LPS depression in baroreflex activity and elevation in dP/dtmax. Molecular studies showed that PPT was most effective in attenuating the upregulated myocardial expressions of NF-κB and iNOS in endotoxic OVX rats. Myocardial expression of the defensive HSP70 was comparably increased by all estrogenic products. Except for improved cardiac spectral activity, none of these functional or molecular entities was affected by medroxyprogesterone acetate (MPA). Overall, our data suggest diverse therapeutic advantages for gonadal hormones in the worsened endotoxic complications in rats with surgical menopause, with probably more favorable role for ERα agonism within this context.


Asunto(s)
Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/etiología , Endotoxemia/complicaciones , Endotoxemia/tratamiento farmacológico , Terapia de Reemplazo de Estrógeno/métodos , Inflamación/tratamiento farmacológico , Inflamación/etiología , Ovariectomía/efectos adversos , Animales , Barorreflejo/efectos de los fármacos , Presión Sanguínea , Citocinas , Endotoxemia/inducido químicamente , Estradiol/uso terapéutico , Receptor alfa de Estrógeno/agonistas , Terapia de Reemplazo de Estrógeno/efectos adversos , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Lipopolisacáridos , Acetato de Medroxiprogesterona/uso terapéutico , Ratas , Ratas Wistar , Moduladores Selectivos de los Receptores de Estrógeno/uso terapéutico , Función Ventricular Izquierda/efectos de los fármacos
8.
Mar Drugs ; 18(5)2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-32380771

RESUMEN

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.


Asunto(s)
Actinobacteria/metabolismo , Antibacterianos/farmacología , Micromonospora/metabolismo , Poríferos/microbiología , Inhibidores de Topoisomerasa II/farmacología , Actinobacteria/aislamiento & purificación , Animales , Antibacterianos/biosíntesis , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Técnicas Bacteriológicas/métodos , Biopelículas/efectos de los fármacos , Girasa de ADN/metabolismo , Pruebas de Enzimas , Fermentación , Metabolómica/métodos , Pruebas de Sensibilidad Microbiana , Micromonospora/aislamiento & purificación , Conformación Molecular , Simulación del Acoplamiento Molecular , Piruvato Quinasa/antagonistas & inhibidores , Piruvato Quinasa/metabolismo , Staphylococcus/efectos de los fármacos , Staphylococcus/enzimología , Relación Estructura-Actividad , Inhibidores de Topoisomerasa II/química , Inhibidores de Topoisomerasa II/aislamiento & purificación , Inhibidores de Topoisomerasa II/metabolismo
9.
Opt Express ; 27(12): 16507-16520, 2019 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-31252875

RESUMEN

Previously, we had proposed a hybrid opto-electronic correlator (HOC), which can achieve the same functionality as that of a holographic optical correlator but without using any holographic medium. Here, we demonstrate experimentally that the HOC is capable of detecting objects in a scale, rotation, and shift invariant manner. First, the polar Mellin transformed (PMT) versions of two images are produced, using a combination of optical and electronic signal processing. The PMT images are then used as the reference and the query inputs for the HOC. The observed correlation signal is used to infer, with high accuracy, the relative scale and angular orientation of the original images. We also discuss practical constraints in reaching a high-speed implementation of such a system. In addition, we describe how these challenges may be overcome for producing an automated version of such a correlator.

10.
J Pharmacol Exp Ther ; 364(2): 170-178, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29133386

RESUMEN

We recently demonstrated a fundamental role for cystathionine-γ lyase (CSE)-derived hydrogen sulfide (H2S) in the cardioprotective effect of the centrally acting drug moxonidine in diabetic rats. Whether a downregulated CSE/H2S system in the rostral ventrolateral medulla (RVLM) underlies neuronal oxidative stress and sympathoexcitation in diabetes has not been investigated. Along with addressing this question, we tested the hypothesis that moxonidine prevents the diabetes-evoked neurochemical effects by restoring CSE/H2S function within its major site of action, the RVLM. Ex vivo studies were performed on RVLM tissues of streptozotocin (55 mg/kg, i.p.) diabetic rats treated daily for 3 weeks with moxonidine (2 or 6 mg/kg; gavage), H2S donor sodium hydrosulfide (NaHS) (3.4 mg/kg, i.p.), CSE inhibitor DL-propargylglycine (DLP) (37.5 mg/kg, i.p.), a combination of DLP with moxonidine, or their vehicle. Moxonidine alleviated RVLM oxidative stress, neuronal injury, and increased tyrosine hydroxylase immunoreactivity (sympathoexcitation) by restoring CSE expression/activity as well as heme oxygenase-1 (HO-1) expression. A pivotal role for H2S in moxonidine-evoked neuroprotection is supported by the following: 1) NaHS replicated the moxonidine-evoked neuroprotection, and the restoration of RVLM HO-1 expression in diabetic rats; and 2) DLP abolished moxonidine-evoked neuroprotection in diabetic rats, and caused RVLM neurotoxicity, reminiscent of a diabetes-evoked neuronal phenotype, in healthy rats. These findings suggest a novel role for RVLM CSE/H2S/HO-1 in moxonidine-evoked neuroprotection and sympathoinhibition, and as a therapeutic target for developing new drugs for alleviating diabetes-evoked RVLM neurotoxicity and cardiovascular anomalies.


Asunto(s)
Cistationina gamma-Liasa/metabolismo , Diabetes Mellitus Experimental/metabolismo , Imidazoles/farmacología , Bulbo Raquídeo/efectos de los fármacos , Bulbo Raquídeo/enzimología , Fármacos Neuroprotectores/farmacología , Sistema Nervioso Simpático/efectos de los fármacos , Animales , Diabetes Mellitus Experimental/enzimología , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Experimental/fisiopatología , Hemo-Oxigenasa 1/metabolismo , Sulfuro de Hidrógeno/metabolismo , Masculino , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos , Sistema Nervioso Simpático/fisiopatología
11.
World J Urol ; 36(11): 1845-1852, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29736609

RESUMEN

PURPOSE: To compare the efficacy of three chemoprophylaxis approaches in prevention of post-transrectal biopsy infectious complications (TBICs). METHODS: Patients were randomly assigned to receive ciprofloxacin 3 days 500 mg B.I.D 3 days starting the night prior to biopsy (standard prophylaxis), augmented prophylaxis using ciprofloxacin and single preprocedure shot of 160 mg gentamicin IM (augmented prophylaxis) and rectal swab culture-based prophylaxis (targeted prophylaxis). Patients were assessed 2 weeks prior to biopsy, at biopsy and 2 weeks after. Primary end point was occurrence of post-TBICs that included simple UTI, febrile UTI or sepsis. Secondary end points were post-biopsy change in the inflammatory markers (TLC, ESR and CRP), unplanned visits, hospitalization and occurrence of fluoroquinolones resistance (FQ-R; bacterial growth on MacConkey agar plate with 10 µg/ml ciprofloxacin) in the fecal carriage of screened men. RESULTS: Between April/2015 and January/2017, standard, augmented and targeted prophylaxes were given to 163, 166 and 167 patients, respectively. Post-TBICs were reported in 43 (26%), 13 (7.8%) and 34 (20.3%) patients following standard, augmented and targeted prophylaxes protocols, respectively (P = 0.000). Post-TBICs included UTI in 23 (4.6%), febrile UTI in 41 (8.2%) and sepsis in 26 (5.2%) patients. Significantly lower number of post-biopsy positive urine culture was depicted in the augmented group (P = 0.000). The number of biopsy cores was statistically different in the three groups (P = 0.004). On multivariate analysis, augmented prophylaxis had independently lower post-TBICs (OR 0.2, 95% CI 0.1-0.4, P = 0.000) when compared with the other two groups regardless of the number of biopsy cores taken (OR 1.07, 95% CI 0.95-1.17, P = 0.229). Post-biopsy hospitalization was needed in four (2%), one (0.6%) and ten (6%) patients following standard, augmented and targeted prophylaxes, respectively (P = 0.014). However, sepsis-related hospitalization was not statistically different. Post-biopsy changes in the inflammatory markers were significantly less in augmented prophylaxis (P < 0.05). FQ-R was depicted in 139 (83.2%) of the screened men. CONCLUSION: Augmented prophylaxis with single-dose gentamicin is an effective and practical approach. Targeted prophylaxis might be reserved for cases with contraindication to gentamicin.


Asunto(s)
Antibacterianos/uso terapéutico , Profilaxis Antibiótica/métodos , Biopsia con Aguja Gruesa/métodos , Ciprofloxacina/uso terapéutico , Gentamicinas/uso terapéutico , Próstata/patología , Sepsis/prevención & control , Infecciones Urinarias/prevención & control , Adenocarcinoma/diagnóstico , Adenocarcinoma/patología , Anciano , Glucemia/metabolismo , Sedimentación Sanguínea , Proteína C-Reactiva/metabolismo , Técnicas de Cultivo , Fiebre/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/patología , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/patología , Prostatitis/diagnóstico , Prostatitis/patología , Recto/microbiología , Sepsis/epidemiología , Cateterismo Urinario/estadística & datos numéricos , Infecciones Urinarias/epidemiología
12.
J Pharmacol Exp Ther ; 361(1): 130-139, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28179472

RESUMEN

Recent findings linked the inhibition in the neuromodulator peptide endothelin-1 (ET-1) level to the high glucose-evoked neurotoxicity. However, definitive neuroprotective role for ET-1 and the major neuronal ET (ET-3) against high glucose-evoked toxicity and the implicated neurochemical responses triggered by their ET-A and ET-B receptors remain unknown. Here, we tested the hypothesis that ET-B activation alleviates high glucose-evoked oxidative stress and cell death. High glucose (100 mM for 48 hours)-evoked cell death was associated with elevation in reactive oxygen species, inhibition of catalase activity, and a paradoxical upregulation of hemeoxygenase-1 expression along with ET-A and ET-B receptors were downregulated and upregulated, respectively. ET-1 or ET-3, in concentrations that had no effect on PC12 cell viability in normal glucose medium, alleviated all high glucose-evoked neurochemical responses, except for the reduction in ET-A receptor expression. Prior (4 hours) incubation with a selective ET-A (BQ123) or ET-B (BQ788) receptor blocker abrogated the neuroprotection conferred by ET-1 or ET-3. However, the ET-B receptor played a greater role because BQ788 abrogated the favorable ET-1- or ET-3-mediated reversal of the ERK1/2 phosphorylation and the inhibition in catalase activity caused by high glucose. These findings suggest that endothelin exerts ET-B receptor-dependent favorable redox and neuroprotective effects against high glucose-evoked oxidative damage and neurotoxicity.


Asunto(s)
Endotelina-1/farmacología , Endotelina-3/farmacología , Glucosa/toxicidad , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Estrés Oxidativo/fisiología , Células PC12 , Ratas
13.
Appl Opt ; 56(10): 2754-2759, 2017 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-28375236

RESUMEN

Optical target recognition using correlators is an important technique for fast verification and identification of images. The hybrid opto-electronic correlator (HOC) recently proposed by us bypasses the need for nonlinear materials such as photorefractive polymer films by using detectors instead, and the phase information is yet conserved by the interference of plane waves with the images. In this paper, we demonstrate experimentally the basic working principle of the HOC architecture using currently available technologies. For matched reference and query images, the output signal shows a sharp peak, indicating a match is found. For an unmatched case, a much lower peak value is observed, indicating no match. We also demonstrate the dependence of the output signal on the phases of the interfering plane waves and describe a technique using an interferometer and a servo for optimizing the output signal. As such, the work reported here paves the way for further development of the HOC for practical applications.

14.
Toxicol Appl Pharmacol ; 289(3): 466-73, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26597895

RESUMEN

We have previously reported that estrogen (E2) exacerbates the depressant effect of chronic nicotine on arterial baroreceptor activity in female rats. Here, we tested the hypothesis that this nicotine effect is modulated by nitric oxide synthase (NOS) and/or heme oxygenase (HO) and their downstream soluble guanylate cyclase (sGC)/phosphatidylinositol 3-kinase (PI3K)/mitogen-activated protein kinases (MAPKs) signaling. We investigated the effects of (i) inhibition or facilitation of NOS or HO on the interaction of nicotine (2mg/kg/day i.p., 2 weeks) with reflex bradycardic responses to phenylephrine in ovariectomized (OVX) rats treated with E2 or vehicle, and (ii) central pharmacologic inhibition of sGC, PI3K, or MAPKs on the interaction. The data showed that the attenuation by nicotine of reflex bradycardia in OVXE2 rats was abolished after treatment with hemin (HO inducer) or l-arginine (NOS substrate). The hemin or l-arginine effect disappeared after inhibition of NOS (Nω-Nitro-l-arginine methyl ester hydrochloride, L-NAME) and HO (zinc protoporphyrin IX, ZnPP), respectively, denoting the interaction between the two enzymatic pathways. E2-receptor blockade (ICI 182,780) reduced baroreflexes in OVXE2 rats but had no effect on baroreflex improvement induced by hemin or l-arginine. Moreover, baroreflex enhancement by hemin was eliminated following intracisternal (i.c.) administration of wortmannin, ODQ, or PD98059 (inhibitors of PI3K, sGC, and extracellular signal-regulated kinases, MAPKERK, respectively). In contrast, the hemin effect was preserved after inhibition of MAPKp38 (SB203580) or MAPKJNK (SP600125). Overall, NOS/HO interruption underlies baroreflex dysfunction caused by nicotine in female rats and the facilitation of NOS/HO-coupled sGC/PI3K/MAPKERK signaling might rectify the nicotine effect.


Asunto(s)
Barorreflejo/efectos de los fármacos , Estrógenos/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Guanilato Ciclasa/metabolismo , Hemo Oxigenasa (Desciclizante)/antagonistas & inhibidores , Nicotina/efectos adversos , Óxido Nítrico Sintasa/antagonistas & inhibidores , Fosfatidilinositol 3-Quinasas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Animales , Arginina/análogos & derivados , Arginina/metabolismo , Inhibidores Enzimáticos/farmacología , Femenino , Hemina/metabolismo , NG-Nitroarginina Metil Éster/metabolismo , Fenilefrina/metabolismo , Ratas , Ratas Wistar , Guanilil Ciclasa Soluble
15.
Jpn J Vet Res ; 63(2): 53-62, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-26164874

RESUMEN

Depression is one of the most famous psychiatric disorders in humans in all over the countries and considered a complex neurobehavioral trait and difficult to identify causal genes. Tail suspension test (TST) and forced swimming test (FST) are widely used for assessing depression-like behavior and antidepressant activity in mice. A variety of antidepressant agents are known to reduce immobility time in both TST and FST. To identify genetic determinants of immobility duration in both tests, we analyzed 101 F2 mice from an intercross between C57BL/6 and DBA/2 strains. Quantitative trait locus (QTL) mapping using 106 microsatellite markers revealed three loci (two significant and one suggestive) and five suggestive loci controlling immobility time in the TST and FST, respectively. Results of QTL analysis suggest a broad description of the genetic architecture underlying depression, providing underpinnings for identifying novel molecular targets for antidepressants to clear the complex genetic mechanisms of depressive disorders.


Asunto(s)
Prueba de Esfuerzo/psicología , Genotipo , Suspensión Trasera/fisiología , Inmovilización , Natación/psicología , Animales , Conducta Animal , Regulación de la Expresión Génica , Marcadores Genéticos , Inmovilización/fisiología , Inmovilización/psicología , Masculino , Ratones , Estrés Fisiológico
16.
J Dent Educ ; 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38741343

RESUMEN

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.

17.
bioRxiv ; 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38405820

RESUMEN

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.

18.
Arch Gynecol Obstet ; 288(4): 759-67, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23543239

RESUMEN

OBJECTIVES: To review the maternal and fetal outcome of triplet, quadruplet and quintuplet gestations following ART, which were managed at a hospital over 11 years. STUDY DESIGN: Retrospective chart review of 150 triplet, 27 quadruplet, and 6 quintuplet pregnancies between January 2001 and December 2011. 25 women aged 50-56 years with triplet pregnancies, were excluded due to lack of data. No prophylactic interventions were used. RESULTS: 300 triplets, 108 quadruplets, and 30 quintuplets were born. The mean maternal age was 30.2 years (SD 4.2 years). Mean gestational age delivery was 32.2 weeks (SD 4.2 weeks). Maternal complications included preterm labor 114 (86 %), prematurity 115 (87 %), anemia 44 (33 %) gestational diabetes 35 (27 %), preeclampsia 33 (25 %), post partum hemorrhage 13 (10 %). Preterm labor was diagnosed in 84 (84 %) triplets, 32 (97 %) of quadru- and quintuplet pregnancies (P > 0.05). Prematurity and preterm labor were major determinants. Of the 438 fetuses born there were 57 (13 %) still births, 77 (18 %) neonatal deaths. 32 (7 %) were early neonatal deaths, 45 (10 %) late neonatal deaths. The majority died due to extreme low birth weight. 75 (17 %) neonates had low apgar score of <7 at 5 min. 22 (5 %) infants had congenital anomalies. Severe respiratory distress syndrome, perinatal asphyxia, very early preterm delivery and perinatal mortality were higher in quadru- and quintuplets (P < 0.05). CONCLUSION: Preterm labor and preterm prematurity were the commonest complications. Neonatal mortality and morbidity was significantly increased in quadru- and quintuplets. Prophylactic interventions were not used in an attempt to prevent preterm labor.


Asunto(s)
Mortalidad Infantil , Enfermedades del Recién Nacido/etiología , Complicaciones del Embarazo/etiología , Embarazo Múltiple , Técnicas Reproductivas Asistidas/efectos adversos , Mortinato , Adulto , Femenino , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Enfermedades del Recién Nacido/epidemiología , Recien Nacido Prematuro , Enfermedades del Prematuro/diagnóstico , Enfermedades del Prematuro/epidemiología , Enfermedades del Prematuro/etiología , Kuwait/epidemiología , Embarazo , Complicaciones del Embarazo/epidemiología , Diagnóstico Prenatal , Estudios Retrospectivos , Mortinato/epidemiología
19.
Egypt Heart J ; 75(1): 63, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37466800

RESUMEN

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.

20.
PLoS One ; 18(5): e0281977, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37159454

RESUMEN

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.


Asunto(s)
Hipotermia , Humanos , Animales , Perros , Células HEK293 , Síndrome , Antiarrítmicos/farmacología , Antiarrítmicos/uso terapéutico , Arritmias Cardíacas/tratamiento farmacológico , Miocitos Cardíacos
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