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1.
PLoS Pathog ; 16(6): e1008640, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32569299

RESUMEN

Ubiquitylation is a common post translational modification of eukaryotic proteins and in the human malaria parasite, Plasmodium falciparum (Pf) overall ubiquitylation increases in the transition from intracellular schizont to extracellular merozoite stages in the asexual blood stage cycle. Here, we identify specific ubiquitylation sites of protein substrates in three intraerythrocytic parasite stages and extracellular merozoites; a total of 1464 sites in 546 proteins were identified (data available via ProteomeXchange with identifier PXD014998). 469 ubiquitylated proteins were identified in merozoites compared with only 160 in the preceding intracellular schizont stage, suggesting a large increase in protein ubiquitylation associated with merozoite maturation. Following merozoite invasion of erythrocytes, few ubiquitylated proteins were detected in the first intracellular ring stage but as parasites matured through trophozoite to schizont stages the apparent extent of ubiquitylation increased. We identified commonly used ubiquitylation motifs and groups of ubiquitylated proteins in specific areas of cellular function, for example merozoite pellicle proteins involved in erythrocyte invasion, exported proteins, and histones. To investigate the importance of ubiquitylation we screened ubiquitin pathway inhibitors in a parasite growth assay and identified the ubiquitin activating enzyme (UBA1 or E1) inhibitor MLN7243 (TAK-243) to be particularly effective. This small molecule was shown to be a potent inhibitor of recombinant PfUBA1, and a structural homology model of MLN7243 bound to the parasite enzyme highlights avenues for the development of P. falciparum specific inhibitors. We created a genetically modified parasite with a rapamycin-inducible functional deletion of uba1; addition of either MLN7243 or rapamycin to the recombinant parasite line resulted in the same phenotype, with parasite development blocked at the schizont stage. Nuclear division and formation of intracellular structures was interrupted. These results indicate that the intracellular target of MLN7243 is UBA1, and this activity is essential for the final differentiation of schizonts to merozoites.


Asunto(s)
Merozoítos/metabolismo , Plasmodium falciparum/metabolismo , Proteínas Protozoarias/metabolismo , Ubiquitina/metabolismo , Ubiquitinación , Humanos , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Ubiquitina/genética
2.
Reproduction ; 163(5): 251-266, 2022 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-35192508

RESUMEN

Sperm capacitation in mammals is a fundamental requirement to acquire their fertilizing capacity. Little is known about the action mechanism of the molecules that prevent capacitation from occurring prematurely. These molecules are known as decapacitation factors (DFs) and they must be removed from the sperm surface for capacitation to occur successfully. Serine protease inhibitor Kazal type 3 (SPINK3) has been proposed as one of these DFs. Here, we evaluate how this protein binds to mouse sperm and its removal kinetics. We describe that SPINK3 is capable of binding to the membrane of mature epididymal sperm through protein-lipid interactions, specifically to lipid rafts subcellular fraction. Moreover, cholera toxin subunit b (CTB) avoids SPINK3 binding. We observe that SPINK3 is removed from the sperm under in vitro capacitating conditions and by the uterine fluid from estrus females. Our ex vivo studies show the removal kinetics of this protein within the female tract, losing SPINK3 formerly from the apical region of the sperm in the uterus and later from the flagellar region within the oviduct. The presence of acrosome-reacted sperm in the female duct concurs with the absence of SPINK3 over its surface.


Asunto(s)
Inhibidores de Serina Proteinasa , Espermatozoides , Acrosoma , Animales , Femenino , Fertilización , Humanos , Masculino , Mamíferos , Ratones , Capacitación Espermática , Espermatozoides/metabolismo
3.
EMBO Rep ; 21(3): e47832, 2020 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-31951090

RESUMEN

Nicotinamide adenine dinucleotide (NAD) and its phosphorylated form (NADP) are vital for cell function in all organisms and form cofactors to a host of enzymes in catabolic and anabolic processes. NAD(P) transhydrogenases (NTHs) catalyse hydride ion transfer between NAD(H) and NADP(H). Membrane-bound NTH isoforms reside in the cytoplasmic membrane of bacteria, and the inner membrane of mitochondria in metazoans, where they generate NADPH. Here, we show that malaria parasites encode a single membrane-bound NTH that localises to the crystalloid, an organelle required for sporozoite transmission from mosquitos to vertebrates. We demonstrate that NTH has an essential structural role in crystalloid biogenesis, whilst its enzymatic activity is required for sporozoite development. This pinpoints an essential function in sporogony to the activity of a single crystalloid protein. Its additional presence in the apicoplast of sporozoites identifies NTH as a likely supplier of NADPH for this organelle during liver infection. Our findings reveal that Plasmodium species have co-opted NTH to a variety of non-mitochondrial organelles to provide a critical source of NADPH reducing power.


Asunto(s)
Malaria/transmisión , NADP Transhidrogenasas , Animales , Mitocondrias/genética , NAD , NADP , NADP Transhidrogenasas/genética
4.
J Cardiothorac Vasc Anesth ; 35(7): 2063-2069, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33750661

RESUMEN

OBJECTIVE: To develop machine learning models that can predict post-transplantation major adverse cardiovascular events (MACE), all-cause mortality, and cardiovascular mortality in patients undergoing liver transplantation (LT). DESIGN: Retrospective cohort study. SETTING: High-volume tertiary care center. PARTICIPANTS: The study comprised 1,459 consecutive patients undergoing LT between January 2008 and December 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: MACE, all-cause mortality, and cardiovascular mortality were modeled using logistic regression, least absolute shrinkage and selection surgery regression, random forests, support vector machine, and gradient-boosted modeling (GBM). All models were built by splitting data into training and testing cohorts, and performance was assessed using five-fold cross-validation based on the area under the receiver operating characteristic curve and Harrell's C statistic. A total of 1,459 patients were included in the final cohort; 1,425 (97.7%) underwent index transplantation, 963 (66.0%) were female, the median age at transplantation was 57 (11-70) years, and the median Model for End-Stage Liver Disease score was 20 (6-40). Across all outcomes, the GBM model XGBoost achieved the highest performance, with an area under the receiver operating curve of 0.71 (95% confidence interval [CI] 0.63-0.79) for MACE, a Harrell's C statistic of 0.64 (95% CI 0.57-0.73) for overall survival, and 0.72 (95% CI 0.59-0.85) for cardiovascular mortality over a mean follow-up of 4.4 years. Examination of Shapley values for the GBM model revealed that on the cohort-wide level, the top influential factors for postoperative MACE were age at transplantation, diabetes, serum creatinine, cirrhosis caused by nonalcoholic steatohepatitis, right ventricular systolic pressure, and left ventricular ejection fraction. CONCLUSION: Machine learning models developed using data from a tertiary care transplantation center achieved good discriminant function in predicting post-LT MACE, all-cause mortality, and cardiovascular mortality. These models can support clinicians in recipient selection and help screen individuals who may be at elevated risk for post-transplantation MACE.


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad Hepática en Estado Terminal , Trasplante de Hígado , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Estudios de Cohortes , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/cirugía , Femenino , Humanos , Trasplante de Hígado/efectos adversos , Aprendizaje Automático , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Volumen Sistólico , Función Ventricular Izquierda
5.
Can J Physiol Pharmacol ; 97(6): 536-543, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30422687

RESUMEN

Increasing reports of successful and safe application of bone marrow derived mesenchymal stem cells (BM-MSCs) for cell therapy are pouring in from numerous studies. However poor survival of transplanted cells in the recipient has impaired the benefits of BM-MSCs based therapies. Therefore cell product preparation procedures pertaining to MSC therapy need to be optimized to improve the survival of transplanted cells. One of the important ex vivo procedures in the preparation of cells for therapy is passaging of BM-MSCs to ensure a suitable number of cells for transplantation, which may affect the turnover of proteins involved in regulation of cell survival and (or) death pathways. In the current study, we investigated the effect of an increase in passage number of BM-MSCs in cell culture on the intracellular protein turnover (protein synthesis, processing, and degradation machinery). We performed proteomic analysis of BM-MSCs at different passages. There was no significant difference observed in the ribosomal, protein processing, and proteasomal pathways related proteins in BM-MSCs with an increase in passage number from P3 to P7. Therefore, expansion of MSCs in the cell culture in clinically relevant passages (Passage 3-7) does not affect the quality of MSCs in terms of intracellular protein synthesis and turnover.


Asunto(s)
Células Madre Mesenquimatosas/citología , Biosíntesis de Proteínas , Proteómica , Animales , Técnicas de Cultivo de Célula , Diferenciación Celular , Retículo Endoplásmico/metabolismo , Masculino , Trasplante de Células Madre Mesenquimatosas , Ratas , Ratas Sprague-Dawley , Ribosomas/metabolismo
6.
Kidney Int ; 93(3): 626-642, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29276101

RESUMEN

A key feature of glomerular diseases such as crescentic glomerulonephritis and focal segmental glomerulosclerosis is the activation, migration and proliferation of parietal epithelial cells. CD44-positive activated parietal epithelial cells have been identified in proliferative cellular lesions in glomerular disease. However, it remains unknown whether CD44-positive parietal epithelial cells contribute to the pathogenesis of scarring glomerular diseases. Here, we evaluated this in experimental crescentic glomerulonephritis and the transgenic anti-Thy1.1 model for collapsing focal segmental glomerulosclerosis in CD44-deficient (cd44-/-) and wild type mice. For both models albuminuria was significantly lower in cd44-/- compared to wild type mice. The number of glomerular Ki67-positive proliferating cells was significantly reduced in cd44-/- compared to wild type mice, which was associated with a reduced number of glomerular lesions in crescentic glomerulonephritis. In collapsing focal segmental glomerulosclerosis, the extracapillary proliferative cellular lesions were smaller in cd44-/- mice, but the number of glomerular lesions was not different compared to wild type mice. For crescentic glomerulonephritis the influx of granulocytes and macrophages into the glomerulus was similar. In vitro, the growth of CD44-deficient murine parietal epithelial cells was reduced compared to wild type parietal epithelial cells, and human parietal epithelial cell migration could be inhibited using antibodies directed against CD44. Thus, CD44-positive proliferating glomerular cells, most likely parietal epithelial cells, are essential in the pathogenesis of scarring glomerular disease.


Asunto(s)
Enfermedad por Anticuerpos Antimembrana Basal Glomerular/inmunología , Células Epiteliales/inmunología , Glomeruloesclerosis Focal y Segmentaria/inmunología , Receptores de Hialuranos/inmunología , Glomérulos Renales/inmunología , Albuminuria/genética , Albuminuria/inmunología , Albuminuria/metabolismo , Animales , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/genética , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/metabolismo , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/patología , Autoanticuerpos/inmunología , Movimiento Celular , Proliferación Celular , Células Cultivadas , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Células Epiteliales/patología , Proteínas de la Matriz Extracelular/metabolismo , Predisposición Genética a la Enfermedad , Glomeruloesclerosis Focal y Segmentaria/genética , Glomeruloesclerosis Focal y Segmentaria/metabolismo , Glomeruloesclerosis Focal y Segmentaria/patología , Granulocitos/inmunología , Granulocitos/metabolismo , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Glomérulos Renales/metabolismo , Glomérulos Renales/patología , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Fenotipo , Transducción de Señal , Antígenos Thy-1/genética , Antígenos Thy-1/inmunología , Antígenos Thy-1/metabolismo
7.
Mol Cell Proteomics ; 15(10): 3243-3255, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27432909

RESUMEN

An essential step in the transmission of the malaria parasite to the Anopheles vector is the transformation of the mature gametocytes into gametes in the mosquito gut, where they egress from the erythrocytes and mate to produce a zygote, which matures into a motile ookinete. Osmiophilic bodies are electron dense secretory organelles of the female gametocytes which discharge their contents during gamete formation, suggestive of a role in gamete egress. Only one protein with no functional annotation, Pfg377, is described to specifically reside in osmiophilic bodies in Plasmodium falciparum Importantly, Pfg377 defective gametocytes lack osmiophilic bodies and fail to infect mosquitoes, as confirmed here with newly produced pfg377 disrupted parasites. The unique feature of Pfg377 defective gametocytes of lacking osmiophilic bodies was here exploited to perform comparative, label free, global and affinity proteomics analyses of mutant and wild type gametocytes to identify components of these organelles. Subcellular localization studies with fluorescent reporter gene fusions and specific antibodies revealed an osmiophilic body localization for four out of five candidate gene products analyzed: the proteases PfSUB2 (subtilisin 2) and PfDPAP2 (Dipeptidyl aminopeptidase 2), the ortholog of the osmiophilic body component of the rodent malaria gametocytes PbGEST and a previously nonannotated 13 kDa protein. These results establish that osmiophilic bodies and their components are dispensable or marginally contribute (PfDPAP2) to gamete egress. Instead, this work reveals a previously unsuspected role of these organelles in P. falciparum development in the mosquito vector.


Asunto(s)
Orgánulos/metabolismo , Plasmodium falciparum/fisiología , Proteómica/métodos , Proteínas Protozoarias/análisis , Animales , Anopheles/parasitología , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/metabolismo , Femenino , Células Germinativas/metabolismo , Mutación , Proteínas Protozoarias/genética , Subtilisinas/metabolismo
8.
Gen Dent ; 66(6): e6-e10, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30444714

RESUMEN

The aim of this study was to evaluate the effect of polyethylene fibers incorporated in a composite resin matrix on the gingival marginal adaptation of Class II slot restorations. Sixty Class II slot cavity preparations were divided into 2 groups. A fiber-reinforced resin (FRR) group received restorations of composite resin mixed with strips of polyethylene fiber, and an unreinforced resin (UR) group was restored with only composite resin. The groups were subdivided on the basis of the adhesive system (etch-and-rinse or self-etch) that was used. Shrinkage stress was evaluated by placing a strain gauge at the buccal surface of the teeth. A scanning electron microscope was used to evaluate marginal adaptation in terms of a continuous margin (CM) at the gingival margin. Statistical analysis included a 2-way analysis of variance with the Holm-Sidak correction for multiple comparisons at a significance level of 0.05. The mean strain value was significantly smaller in the FRR group (185 [SD 37] µm/m) than in the UR group (295 [SD 21] µm/m). The FRR group presented with a mean CM value of 80.2% (SD 4.6%), which was significantly higher than that of the UR group, which had an overall CM value of 64.4% (SD 4.2%). There was no statistically significant difference between the adhesive subgroups with regard to strain or percentage of CM. The results showed that the incorporation of polyethylene fibers in a composite resin matrix can help to improve gingival marginal adaptation in Class II cavities.


Asunto(s)
Resinas Compuestas/uso terapéutico , Adaptación Marginal Dental , Restauración Dental Permanente/métodos , Polietileno/uso terapéutico , Análisis del Estrés Dental , Humanos
9.
Proc Natl Acad Sci U S A ; 111(32): 11834-9, 2014 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-25071177

RESUMEN

Posttranslational modifications of histone tails in chromatin template can result from environmental experiences such as stress and substance abuse. However, the role of epigenetic modifications as potential predisposing factors in affective behavior is less well established. To address this question, we used our selectively bred lines of high responder (bHR) and low responder (bLR) rats that show profound and stable differences in affective responses, with bLRs being prone to anxiety- and depression-like behavior and bHRs prone to addictive behavior. We first asked whether these phenotypes are associated with basal differences in epigenetic profiles. Our results reveal broad between-group differences in basal levels of trimethylated histone protein H3 at lysine 9 (H3K9me3) in hippocampus (HC), amygdala, and nucleus accumbens. Moreover, levels of association of H3K9me3 at Glucocorticoid Receptor (GR) and Fibroblast growth Factor 2 (FGF2) promoters differ reciprocally between bHRs and bLRs in these regions, consistent with these genes' opposing levels of expression and roles in modulating anxiety behavior. Importantly, this basal epigenetic pattern is modifiable by FGF2, a factor that modulates anxiety behavior. Thus, early-life FGF2, which decreases anxiety, altered the levels of H3K9me3 and its binding at FGF2 and GR promoters of bLRs rendering them more similar to bHRs. Conversely, knockdown of HC FGF2 altered both anxiety behavior and levels of H3K9me3 in bHRs, rendering them more bLR-like. These findings implicate FGF2 as a modifier of epigenetic mechanisms associated with emotional responsiveness, and point to H3K9me3 as a key player in the regulation of affective vulnerability.


Asunto(s)
Afecto/fisiología , Conducta Animal/fisiología , Emociones/fisiología , Epigénesis Genética , Factor 2 de Crecimiento de Fibroblastos/genética , Histonas/química , Histonas/metabolismo , Animales , Ensamble y Desensamble de Cromatina , Metilación de ADN , Factor 2 de Crecimiento de Fibroblastos/deficiencia , Técnicas de Silenciamiento del Gen , Hipocampo/metabolismo , Regiones Promotoras Genéticas , Ratas , Receptores de Glucocorticoides/genética
10.
Blood Cells Mol Dis ; 58: 35-44, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27067487

RESUMEN

The phosphorylation status of red blood cell proteins is strongly altered during the infection by the malaria parasite Plasmodium falciparum. We identify the key phosphorylation events that occur in the erythrocyte membrane and cytoskeleton during infection, by a comparative analysis of global phospho-proteome screens between infected (obtained at schizont stage) and uninfected RBCs. The meta-analysis of reported mass spectrometry studies revealed a novel compendium of 495 phosphorylation sites in 182 human proteins with regulatory roles in red cell morphology and stability, with about 25% of these sites specific to infected cells. A phosphorylation motif analysis detected 7 unique motifs that were largely mapped to kinase consensus sequences of casein kinase II and of protein kinase A/protein kinase C. This analysis highlighted prominent roles for PKA/PKC involving 78 phosphorylation sites. We then compared the phosphorylation status of PKA (PKC) specific sites in adducin, dematin, Band 3 and GLUT-1 in uninfected RBC stimulated or not by cAMP to their phosphorylation status in iRBC. We showed cAMP-induced phosphorylation of adducin S59 by immunoblotting and we were able to demonstrate parasite-induced phosphorylation for adducin S726, Band 3 and GLUT-1, corroborating the protein phosphorylation status in our erythrocyte phosphorylation site compendium.


Asunto(s)
Eritrocitos/parasitología , Malaria Falciparum/metabolismo , Plasmodium falciparum/fisiología , Proteoma/metabolismo , Secuencia de Aminoácidos , AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/análisis , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Citoesqueleto/química , Citoesqueleto/metabolismo , Citoesqueleto/parasitología , Eritrocitos/química , Eritrocitos/metabolismo , Transportador de Glucosa de Tipo 1/análisis , Transportador de Glucosa de Tipo 1/metabolismo , Humanos , Fosforilación , Proteoma/análisis
11.
J Neurosci ; 34(7): 2583-91, 2014 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-24523548

RESUMEN

Interleukin-1ß (IL-1ß) is an inflammatory cytokine that plays a prominent role in stress-induced behavioral changes. In a model of repeated social defeat (RSD), elevated IL-1ß expression in the brain was associated with recruitment of primed macrophages that were necessary for development of anxiety-like behavior. Moreover, microglia activation and anxiety-like behavior associated with RSD did not occur in IL-1 receptor type-1 knock-out (IL-1R1(KO)) mice. Therefore, the objective of this study was to examine the role of IL-1 signaling in RSD-induced macrophage trafficking to the brain and anxiety-like behavior. Initial studies revealed that RSD did not increase circulating myeloid cells in IL-1R1(KO) mice, resulting in limited macrophage trafficking to the brain. In addition, IL-1R1(KO) bone marrow-chimera mice showed that IL-1R1 expression was essential for macrophage trafficking into the brain. To differentiate cellular mediators of stress-induced IL-1 signaling, endothelial-specific IL-1R1 knock-down (eIL-1R1kd) mice were used. Both wild-type (WT) and eIL-1R1kd mice had increased circulating monocytes, recruitment of macrophages to the brain, and altered microglia activation after RSD. Nonetheless, RSD-induced expression of IL-1ß, TNF-α, and IL-6 mRNA in brain CD11b(+) cells was attenuated in eIL-1R1kd mice compared with WT. Moreover, anxiety-like behavior did not develop in eIL-1R1kd mice. Collectively, these findings demonstrated that there was limited RSD-induced priming of myeloid cells in IL-1R1(KO) mice and disrupted propagation of neuroinflammatory signals in the brain of eIL-1R1kd mice. Furthermore, these data showed that transduction of IL-1 signaling by endothelial cells potentiates stress-induced neuroinflammation and promotes anxiety-like behavior.


Asunto(s)
Ansiedad/metabolismo , Quimiotaxis de Leucocito/fisiología , Interleucina-1/metabolismo , Receptores Tipo I de Interleucina-1/metabolismo , Transducción de Señal/fisiología , Estrés Psicológico/metabolismo , Animales , Conducta Animal/fisiología , Encéfalo/metabolismo , Encéfalo/patología , Células Endoteliales/metabolismo , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Tipo I de Interleucina-1/deficiencia
12.
J Hepatol ; 62(2): 325-31, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25152204

RESUMEN

BACKGROUND & AIMS: Portal hypertension is characterized by reduced hepatic eNOS activity. Asymmetric-dimethylarginine (ADMA), an eNOS inhibitor, is elevated in cirrhosis and correlates with the severity of portal hypertension. Dimethylarginine dimethylaminohydrolase-1 (DDAH-1) is the key enzyme metabolizing hepatic ADMA. This study characterized DDAH-1 in cirrhosis, and explored hepatic DDAH-1 reconstitution through farnesoid X receptor (FXR) agonism and DDAH-1 gene therapy. METHODS: DDAH-1 immunohistochemistry was conducted on human cirrhosis and healthy liver tissue. Subsequently, sham-operated or bile-duct-ligated (BDL) cirrhosis rats were treated with the FXR agonist obeticholic acid (OA, 5 mg/kg) or vehicle for 5 days. Further, animals underwent hydrodynamic injection with DDAH-1-expressing plasmid or saline control, which resulted in the following groups: sham+saline, BDL+saline, BDL+DDAH-1-plasmid. Portal pressure (PP) measurements were performed. Plasma ALT was measured by COBAS INTEGRA, DDAH-1 expression by qPCR and Western blot, eNOS activity by radiometric assay. RESULTS: Immunohistochemistry and Western-blotting confirmed hepatic DDAH-1 was restricted to hepatocytes, and expression decreased significantly in cirrhosis. In BDL rats, reduced DDAH-1 expression was associated with elevated hepatic ADMA, reduced eNOS activity and high PP. OA treatment significantly increased DDAH-1 expression, reduced hepatic tissue ADMA, and increased liver NO generation. PP was significantly reduced in BDL+OA vs. BDL+vehicle (8±1 vs. 13.5±0.6 mmHg; p<0.01) with no change in the mean arterial pressure (MAP). Similarly, DDAH-1 hydrodynamic injection significantly increased hepatic DDAH-1 gene and protein expression, and significantly reduced PP in BDL+DDAH-1 vs. BDL+saline (p<0.01). CONCLUSIONS: This study demonstrates DDAH-1 is a specific molecular target for portal pressure reduction, through actions on ADMA-mediated regulation of eNOS activity. Our data support translational studies, targeting DDAH-1 in cirrhosis and portal hypertension.


Asunto(s)
Amidohidrolasas/genética , Regulación de la Expresión Génica , Terapia Genética/métodos , Hipertensión Portal/tratamiento farmacológico , Cirrosis Hepática/genética , Hígado/enzimología , ARN/genética , Amidohidrolasas/biosíntesis , Animales , Biomarcadores/metabolismo , Biopsia , Western Blotting , Células Cultivadas , Modelos Animales de Enfermedad , Humanos , Hipertensión Portal/enzimología , Hipertensión Portal/etiología , Inmunohistoquímica , Hígado/patología , Cirrosis Hepática/complicaciones , Cirrosis Hepática/enzimología , Masculino , Reacción en Cadena de la Polimerasa , Ratas , Ratas Sprague-Dawley
13.
Liver Int ; 35(3): 724-34, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24703488

RESUMEN

BACKGROUND & AIMS: Acute-on-chronic liver failure (ACLF) is characterized by acute deterioration of cirrhosis, systemic inflammation and multi-organ failure. Inflammation is also key to the pathobiology of portal hypertension. This study aims to define the relationship between systemic and hepatic haemodynamics in patients with ACLF. METHODS: Sixty patients with alcoholic cirrhosis were prospectively enrolled - stable cirrhosis (SC, n = 27), acute decompensation without ACLF (AD, n = 14) and ACLF (n = 19) - and managed with standard therapy. Systemic and hepatic haemodynamic studies were performed, and patients were followed up for 3 months. Plasma norepinephrine, cytokine profile, nitrate/nitrite and malondialdehyde levels were measured. RESULTS: Three-month mortality was as follows: SC - none; AD - 14%; ACLF - 47.2% (P < 0.001). Mean arterial pressure was lowest in the ACLF group (P < 0.001). ACLF patients had significantly higher hepatic vein pressure gradient (HVPG), while the hepatic blood flow was markedly reduced with an increase in intrahepatic resistance, which predicted mortality (AUROC: 0.87, P < 0.0001). In ACLF, the severity of intrahepatic resistance correlated with markers of inflammatory response, norepinephrine levels, creatinine levels and severity of encephalopathy. Modelling data showed that the high norepinephrine levels in ACLF may contribute to the right shift of the HVPG-hepatic blood flow relationship and its levels correlated with inflammatory markers and mortality (AUROC: 0.90; P < 0.0001). CONCLUSIONS: The disturbances in systemic and hepatic haemodynamics in alcohol-related ACLF are associated with dysregulated inflammation, multi-organ failure and marked activation of the sympathetic nervous system. These abnormalities predict high mortality rates in alcohol-related ACLF patients.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada/complicaciones , Insuficiencia Hepática Crónica Agudizada/mortalidad , Cirrosis Hepática Alcohólica/complicaciones , Insuficiencia Multiorgánica/complicaciones , Síndrome de Respuesta Inflamatoria Sistémica/complicaciones , Adulto , Anciano , Biomarcadores , Femenino , Hemodinámica , Encefalopatía Hepática/complicaciones , Humanos , Hipertensión Portal/complicaciones , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Insuficiencia Renal/complicaciones
14.
Cardiovasc Drugs Ther ; 29(6): 573-588, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26477661

RESUMEN

Remote Ischemic Preconditioning (RIPC) is a non-invasive cardioprotective intervention that involves brief cycles of limb ischemia and reperfusion. This is typically delivered by inflating and deflating a blood pressure cuff on one or more limb(s) for several cycles, each inflation-deflation being 3-5 min in duration. RIPC has shown potential for protecting the heart and other organs from injury due to lethal ischemia and reperfusion injury, in a variety of clinical settings. The mechanisms underlying RIPC are under intense investigation but are just beginning to be deciphered. Emerging evidence suggests that RIPC has the potential to improve exercise performance, via both local and remote mechanisms. This review discusses the clinical studies that have investigated the role of RIPC in cardioprotection as well as those studying its applicability in improving athletic performance, while examining the potential mechanisms involved.

15.
J Med Genet ; 51(11): 737-47, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25228304

RESUMEN

BACKGROUND: Autism spectrum disorders (ASDs) are common and have a strong genetic basis, yet the cause of ∼70-80% ASDs remains unknown. By clinical cytogenetic testing, we identified a family in which two brothers had ASD, mild intellectual disability and a chromosome 22 pericentric inversion, not detected in either parent, indicating de novo mutation with parental germinal mosaicism. We hypothesised that the rearrangement was causative of their ASD and localised the chromosome 22 breakpoints. METHODS: The rearrangement was characterised using fluorescence in situ hybridisation, Southern blotting, inverse PCR and dideoxy-sequencing. Open reading frames and intron/exon boundaries of the two physically disrupted genes identified, TCF20 and TNRC6B, were sequenced in 342 families (260 multiplex and 82 simplex) ascertained by the International Molecular Genetic Study of Autism Consortium (IMGSAC). RESULTS: IMGSAC family screening identified a de novo missense mutation of TCF20 in a single case and significant association of a different missense mutation of TCF20 with ASD in three further families. Through exome sequencing in another project, we independently identified a de novo frameshifting mutation of TCF20 in a woman with ASD and moderate intellectual disability. We did not identify a significant association of TNRC6B mutations with ASD. CONCLUSIONS: TCF20 encodes a transcriptional coregulator (also termed SPBP) that is structurally and functionally related to RAI1, the critical dosage-sensitive protein implicated in the behavioural phenotypes of the Smith-Magenis and Potocki-Lupski 17p11.2 deletion/duplication syndromes, in which ASD is frequently diagnosed. This study provides the first evidence that mutations in TCF20 are also associated with ASD.


Asunto(s)
Trastornos Generalizados del Desarrollo Infantil/genética , Cromosomas Humanos Par 22/genética , Reordenamiento Génico/genética , Mutación/genética , Factores de Transcripción/genética , Niño , Puntos de Rotura del Cromosoma , Humanos , Hibridación Fluorescente in Situ , Lactante , Masculino , Análisis de Secuencia de ADN
16.
Anesth Prog ; 62(4): 135-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26650491

RESUMEN

The present study tested the hypothesis that the amount and severity of preoperative pain will affect the anesthetic efficacy of inferior alveolar nerve block (IANB) in patients with symptomatic irreversible pulpitis. One-hundred seventy-seven adult volunteer subjects, actively experiencing pain in a mandibular molar, participated in this prospective double-blind study carried out at 2 different centers. The patients were classified into 3 groups on the basis of severity of preoperative pain: mild, 1-54 mm on the Heft-Parker visual analog scale (HP VAS); moderate, 55-114 mm; and severe, greater than 114 mm. After IANB with 1.8 mL of 2% lidocaine, endodontic access preparation was initiated. Pain during treatment was recorded using the HP VAS. The primary outcome measure was the ability to undertake pulp access and canal instrumentation with no or mild pain. The success rates were statistically analyzed by multiple logistic regression test. There was a significant difference between the mild and severe preoperative pain group (P = .03). There was a positive correlation between the values of preoperative and intraoperative pain (r = .2 and .4 at 2 centers). The amount of preoperative pain can affect the anesthetic success rates of IANB in patients with symptomatic irreversible pulpitis.


Asunto(s)
Anestesia Dental/métodos , Nervio Mandibular/efectos de los fármacos , Bloqueo Nervioso/métodos , Odontalgia/fisiopatología , Adulto , Anestésicos Locales/administración & dosificación , Método Doble Ciego , Epinefrina/administración & dosificación , Femenino , Humanos , Lidocaína/administración & dosificación , Masculino , Persona de Mediana Edad , Diente Molar/patología , Dimensión del Dolor/métodos , Estudios Prospectivos , Pulpitis/fisiopatología , Pulpitis/terapia , Preparación del Conducto Radicular/métodos , Factores de Tiempo , Resultado del Tratamiento , Vasoconstrictores/administración & dosificación , Adulto Joven
17.
Mol Cell Biochem ; 388(1-2): 95-111, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24281856

RESUMEN

Diabetic nephropathy (DN) is a microvascular complication associated with diabetes causing slow deterioration of kidneys leading to end-stage renal disease. Timely intervention and diagnosis are crucial in order to ameliorate and halt the progression of DN. Current diagnosis of DN consists of urine assays for detection of microalbuminuria, which have inadequate specificity and sensitivity. Hence, there arises a need to discover stage-specific biomarkers which can aid in the early detection of DN and also in identifying the mechanisms underlying pathogenesis of DN. Therefore the present study was undertaken to identify the differentially expressed proteins in the urine and to examine the pattern of proteomic changes occurring in the rat kidneys during the course of progression of streptozotocin-induced model of DN in rats. Two-dimensional gel electrophoresis coupled to MALDI-TOF mass spectrometry was employed to identify the differentially expressed proteins under diabetic conditions. Among the identified proteins Calgranulin A and Calgranulin B appeared in the urinary proteome at the fourth week of induction of diabetes while we recorded a time-dependent decrease in the expression of major urinary protein (alpha 2u globulin) in the urine as well as kidneys of diabetic rats. Parallel monitoring of targeted proteomic changes in the renal proteome revealed an increase in histone H2B phosphorylation at serine14 along with a gradual decrease in Bcl-2 and MMP-13 expression during the course of progression and development of streptozotocin-induced DN.


Asunto(s)
Biomarcadores/orina , Nefropatías Diabéticas/orina , Riñón/patología , Proteoma/análisis , alfa-Globulinas/orina , Animales , Nitrógeno de la Urea Sanguínea , Cadherinas/orina , Calgranulina A/biosíntesis , Calgranulina B/orina , Colágeno/orina , Creatinina/sangre , Diabetes Mellitus Experimental/orina , Electroforesis en Gel Bidimensional , Fibronectinas/orina , Masculino , Metaloproteinasa 13 de la Matriz/orina , Proteínas Serina-Treonina Quinasas/orina , Proteínas Tirosina Quinasas/orina , Ratas , Ratas Sprague-Dawley , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Estreptozocina
18.
Int J Adolesc Med Health ; 26(4): 551-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24572975

RESUMEN

BACKGROUND: Adolescence is a crucial stage of life. The development and practice of various risk behaviors predisposes the risk of getting injured and consequences in later life. STUDY METHODS: This cross-sectional study was conducted among 381 adolescents (15-19 years) studying in different schools and colleges of Udupi. The Youth Risk Behavior Survey (YRBS), Center for Disease Control (CDC) Questionnaire and the Atlanta Questionnaire and Guidelines was adopted for data collection. Behaviors such as poor obeying traffic rules while driving, violence at school premises, and suicidal thoughts of the participants were explored. Univariate analysis followed by multivariate logistic regression was done to estimate the predictors of violence-related behavior using the Statistical Packages for Social Sciences (SPSS) v. 20. RESULTS: In our study, 27.03% of students (total=381) had knowledge of traffic rules in detail, where 65% drove a motorized vehicle. Nearly 75% of students did not use a helmet or seatbelt while driving and 17% used a mobile phone for either talking or texting while driving. Considering all violence risk behaviors, 33.07% of students had at least and 18% had at least two violence-related risk behaviors. Nearly 21.78% thought of hitting somebody, 16.34% of boys and 9.5% of girls carried sharp objects to school, 18.81% of boys and 10.39% of girls damaged or stole other students' property, 18.37% bullied others in the past month at the school campus, and 11.32% were involved in serious fights. Out of 381 students, 114 (30.32%) were bullied, 10% had been slapped intentionally, and 18% of girls felt unsafe to go out of their home because of threat compared with 15% of boys. In total, 71 (18.93%) students thought of suicide and 22 of them attempted it. Logistic regression showed that boys [odds ratio (OR): 1.72, 95% confidence interval (CI): 1.02-2.93) and students of 16 years of age (OR: 3.02, 95% CI: 1.06-9.02) affected or victimized by violent activities at school (OR: 3.23, 95% CI: 1.76-5.93) and bullied by others (OR: 2.6, 95% CI: 1.55-4.36) were determining factors for violence-related behaviors after adjusting for other variables. CONCLUSION: There is a need to identify students at risk and for intervention addressing the risk factors. Further qualitative studies could provide more insight.


Asunto(s)
Conducta del Adolescente , Asunción de Riesgos , Violencia/estadística & datos numéricos , Heridas y Lesiones/epidemiología , Adolescente , Conducción de Automóvil/psicología , Conducción de Automóvil/estadística & datos numéricos , Estudios Transversales , Femenino , Humanos , India/epidemiología , Masculino , Factores de Riesgo , Factores Socioeconómicos , Trastornos Relacionados con Sustancias/epidemiología , Adulto Joven
19.
Med Chem ; 20(4): 369-384, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38192143

RESUMEN

The worldwide impact of cancer is further compounded by the constraints of current anticancer medications, which frequently exhibit a lack of selectivity, raise safety apprehensions, result in significant adverse reactions, and encounter resistance mechanisms. The current situation highlights the pressing need to develop novel and more precise anticancer agents that prioritize safety and target specificity. Remarkably, more than 85% of drugs with physiological activity contain heterocyclic structures or at least one heteroatom. Nitrogen-containing heterocycles hold a significant position among these compounds, emerging as the most prevalent framework within the realm of heterocyclic chemistry. This article explores the medicinal chemistry behind these molecules, highlighting their potential as game-changing possibilities for anticancer medication development. The analysis highlights the inherent structural variety in nitrogen-containing heterocycles, revealing their potential to be customized for creating personalized anticancer medications. It also emphasizes the importance of computational techniques and studies on the relationships between structure and activity, providing a road map for rational medication design and optimization. Nitrogen- containing heterocycles are a promising new area of study in the fight against cancer, and this review summarises the state of the field so far. By utilizing their inherent characteristics and exploiting cooperative scientific investigations, these heterocyclic substances exhibit potential at the forefront of pioneering therapeutic approaches in combating the multifaceted obstacles posed by cancer.


Asunto(s)
Antineoplásicos , Descubrimiento de Drogas , Compuestos Heterocíclicos , Nitrógeno , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Compuestos Heterocíclicos/síntesis química , Humanos , Nitrógeno/química , Neoplasias/tratamiento farmacológico , Relación Estructura-Actividad , Estructura Molecular , Animales
20.
Med Chem ; 20(5): 487-502, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38279757

RESUMEN

This study aims to provide a thorough analysis of nitrogen-containing heterocycles, focusing on their therapeutic implications for the development of targeted and effective antiviral drugs. To better understand how nitrogen-containing heterocycles can be used to create antiviral drugs, this review adopts a systematic literature review strategy to compile and analyze pertinent research studies. It combines information from various fields to understand better the compounds' mode of action and their therapeutic potential. This review paper summarizes data from multiple sources to highlight the promising potential of heterocycles containing nitrogen as promising possibilities for future antiviral treatments. The capacity to engage selectively and modulate critical pathways bodes well for their use in developing new viral therapies. In conclusion, nitrogen-containing heterocycles are shown to be of utmost importance in the field of medicinal chemistry, as emphasized by the review paper. It emphasizes the central importance of chemical insights and pharmacological potential in developing novel and effective antiviral medicines by bringing them together.


Asunto(s)
Antivirales , Compuestos Heterocíclicos , Nitrógeno , Antivirales/farmacología , Antivirales/química , Compuestos Heterocíclicos/química , Compuestos Heterocíclicos/farmacología , Humanos , Nitrógeno/química , Animales
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