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1.
Int J Cancer ; 151(3): 422-434, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35411939

RESUMEN

Abiraterone acetate plus prednisolone (AAP) previously demonstrated improved survival in STAMPEDE, a multiarm, multistage platform trial in men starting long-term hormone therapy for prostate cancer. This long-term analysis in metastatic patients was planned for 3 years after the first results. Standard-of-care (SOC) was androgen deprivation therapy. The comparison randomised patients 1:1 to SOC-alone with or without daily abiraterone acetate 1000 mg + prednisolone 5 mg (SOC + AAP), continued until disease progression. The primary outcome measure was overall survival. Metastatic disease risk group was classified retrospectively using baseline CT and bone scans by central radiological review and pathology reports. Analyses used Cox proportional hazards and flexible parametric models, accounting for baseline stratification factors. One thousand and three patients were contemporaneously randomised (November 2011 to January 2014): median age 67 years; 94% newly-diagnosed; metastatic disease risk group: 48% high, 44% low, 8% unassessable; median PSA 97 ng/mL. At 6.1 years median follow-up, 329 SOC-alone deaths (118 low-risk, 178 high-risk) and 244 SOC + AAP deaths (75 low-risk, 145 high-risk) were reported. Adjusted HR = 0.60 (95% CI: 0.50-0.71; P = 0.31 × 10-9 ) favoured SOC + AAP, with 5-years survival improved from 41% SOC-alone to 60% SOC + AAP. This was similar in low-risk (HR = 0.55; 95% CI: 0.41-0.76) and high-risk (HR = 0.54; 95% CI: 0.43-0.69) patients. Median and current maximum time on SOC + AAP was 2.4 and 8.1 years. Toxicity at 4 years postrandomisation was similar, with 16% patients in each group reporting grade 3 or higher toxicity. A sustained and substantial improvement in overall survival of all metastatic prostate cancer patients was achieved with SOC + abiraterone acetate + prednisolone, irrespective of metastatic disease risk group.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Neoplasias de la Próstata , Acetato de Abiraterona/uso terapéutico , Anciano , Antagonistas de Andrógenos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estudios de Seguimiento , Hormonas , Humanos , Masculino , Prednisolona/uso terapéutico , Prednisona/uso terapéutico , Neoplasias de la Próstata/patología , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Estudios Retrospectivos , Resultado del Tratamiento
2.
Hum Mol Genet ; 27(4): 691-705, 2018 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29300972

RESUMEN

UBTF (upstream binding transcription factor) exists as two isoforms; UBTF1 regulates rRNA transcription by RNA polymerase 1, whereas UBTF2 regulates mRNA transcription by RNA polymerase 2. Herein, we describe 4 patients with very similar patterns of neuroregression due to recurrent de novo mutations in UBTF (GRCh37/hg19, NC_000017.10: g.42290219C > T, NM_014233.3: c.628G > A) resulting in the same amino acid change in both UBTF1 and UBTF2 (p.Glu210Lys [p.E210K]). Disease onset in our cohort was at 2.5 to 3 years and characterized by slow progression of global motor, cognitive and behavioral dysfunction. Notable early features included hypotonia with a floppy gait, high-pitched dysarthria and hyperactivity. Later features included aphasia, dystonia, and spasticity. Speech and ambulatory ability were lost by the early teens. Magnetic resonance imaging showed progressive generalized cerebral atrophy (supratentorial > infratentorial) with involvement of both gray and white matter. Patient fibroblasts showed normal levels of UBTF transcripts, increased expression of pre-rRNA and 18S rRNA, nucleolar abnormalities, markedly increased numbers of DNA breaks, defective cell-cycle progression, and apoptosis. Expression of mutant human UBTF1 in Drosophila neurons was lethal. Although no loss-of-function variants are reported in the Exome Aggregation Consortium (ExAC) database and Ubtf-/- is early embryonic lethal in mice, Ubtf+/- mice displayed only mild motor and behavioral dysfunction in adulthood. Our data underscore the importance of including UBTF E210K in the differential diagnosis of neuroregression and suggest that mainly gain-of-function mechanisms contribute to the pathogenesis of the UBTF E210K neuroregression syndrome.


Asunto(s)
Mutación Missense/genética , Proteínas del Complejo de Iniciación de Transcripción Pol1/genética , Preescolar , Disartria/genética , Femenino , Ataxia de la Marcha/genética , Humanos , Imagen por Resonancia Magnética , Masculino , Hipotonía Muscular/genética , Linaje , ARN Ribosómico 18S/genética
3.
Neurobiol Dis ; 98: 52-65, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27890709

RESUMEN

Loss-of-function mutations in SGCE, which encodes ε-sarcoglycan (ε-SG), cause myoclonus-dystonia syndrome (OMIM159900, DYT11). A "major" ε-SG protein derived from CCDS5637.1 (NM_003919.2) and a "brain-specific" protein, that includes sequence derived from alternative exon 11b (CCDS47642.1, NM_001099400.1), are reportedly localized in post- and pre-synaptic membrane fractions, respectively. Moreover, deficiency of the "brain-specific" isoform and other isoforms derived from exon 11b may be central to the pathogenesis of DYT11. However, no animal model supports this hypothesis. Gene-trapped ES cells (CMHD-GT_148G1-3, intron 9 of NM_011360) were used to generate a novel Sgce mouse model (C57BL/6J background) with markedly reduced expression of isoforms derived from exons 3' to exon 9 of NM_011360. Among those brain regions analyzed in adult (2month-old) wild-type (WT) mice, cerebellum showed the highest relative expression of isoforms incorporating exon 11b. Homozygotes (SgceGt(148G1)Cmhd/Gt(148G1)Cmhd or SgceGt/Gt) and paternal heterozygotes (Sgcem+/pGt, m-maternal, p-paternal) showed 60 to 70% reductions in expression of total Sgce. Although expression of the major (NM_011360) and brain-specific (NM_001130189) isoforms was markedly reduced, expression of short isoforms was preserved and relatively small amounts of chimeric ε-SG/ß-galactosidase fusion protein was produced by the Sgce gene-trap locus. Immunoaffinity purification followed by mass spectrometry assessments of Sgcem+/pGt mouse brain using pan- or brain-specific ε-SG antibodies revealed significant reductions of ε-SG and other interacting sarcoglycans. Genome-wide gene-expression data using RNA derived from adult Sgcem+/pGt mouse cerebellum showed that the top up-regulated genes were involved in cell cycle, cellular development, cell death and survival, while the top down-regulated genes were associated with protein synthesis, cellular development, and cell death and survival. In comparison to WT littermates, Sgcem+/pGt mice exhibited "tiptoe" gait and stimulus-induced appendicular posturing between Postnatal Days 14 to 16. Abnormalities noted in older Sgcem+/pGt mice included reduced body weight, altered gait dynamics, and reduced open-field activity. Overt spontaneous or stimulus-sensitive myoclonus was not apparent on the C57BL/6J background or mixed C57BL/6J-BALB/c and C57BL/6J-129S2 backgrounds. Our data confirm that mouse Sgce is a maternally imprinted gene and suggests that short Sgce isoforms may compensate, in part, for deficiency of major and brain-specific Sgce isoforms.


Asunto(s)
Encéfalo/metabolismo , Trastornos Distónicos/metabolismo , Sarcoglicanos/metabolismo , Animales , Ansiedad/metabolismo , Modelos Animales de Enfermedad , Conducta Exploratoria/fisiología , Femenino , Marcha/fisiología , Regulación del Desarrollo de la Expresión Génica , Masculino , Ratones de la Cepa 129 , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Actividad Motora/fisiología , Fenotipo , Isoformas de Proteínas/metabolismo
5.
Neurochem Res ; 38(8): 1580-9, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23640177

RESUMEN

Alzheimer's disease (AD) is characterized by the presence of neuropathological lesions containing amyloid plaques (APs) and neurofibrillary tangles (NFTs) associated with neuroinflammation and neuronal degeneration. Hippocampus is one of the earliest and severely damaged areas in AD brain. Glia maturation factor (GMF), a known proinflammatory molecule is up-regulated in AD. Here, we have investigated the expression and distribution of GMF in relation to the distribution of APs and NFTs in the hippocampus of AD brains. Our immunohistochemical results showed GMF is expressed specifically in the vicinity of high density of APs and NFTs in the hippocampus of AD patients. Moreover, reactive astrocytes and activated microglia surrounds the APs and NFTs. We further demonstrate that GMF immunoreactive glial cells were increased at the sites of Tau containing NFTs and APs of hippocampus in AD brains. In conclusion, up-regulated expression of GMF in the hippocampus, and the co-localization of GMF and thioflavin-S stained NFTs and APs suggest that GMF may play important role in the pathogenesis of AD.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Factor de Maduración de la Glia/metabolismo , Hipocampo/metabolismo , Humanos
6.
CNS Neurol Disord Drug Targets ; 22(2): 289-303, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35366786

RESUMEN

Although reducing psychotic symptoms in schizophrenia has been a major focus of therapeutic interventions for decades, improving cognition is considered a better predictor of functional outcomes. However, the most commonly prescribed antipsychotic drugs (APDs) show only marginal beneficial effects on cognition in patients with schizophrenia. The neural mechanisms underlying cognitive disturbances in schizophrenia remain unknown that making drug development efforts very challenging. Since neurotrophic factors are the primary architects of neurogenesis, synaptic plasticity, learning, and memory, the findings from preclinical and clinical studies that assess changes in neurogenesis and neurotrophic factors and their relationship to cognitive performance in schizophrenia, and how these mechanisms might be impacted by APD treatment, may provide valuable clues in developing therapies to combat cognitive deficit in schizophrenia. Numerous evidence produced over the years suggests a deficit in a wide spectrum of neurotrophic factors in schizophrenia. Since schizophrenia is considered a neurodevelopmental disorder, early intervention with neurotrophic factors may be more effective in ameliorating the cognitive deficits and psychopathological symptoms associated with this pathology. In this context, results from initial clinical trials with neurotrophic factors and their future potential to improve cognition and psychosocial functioning in schizophrenia are discussed.


Asunto(s)
Antipsicóticos , Esquizofrenia , Humanos , Antipsicóticos/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Factores de Crecimiento Nervioso , Cognición
7.
Med Image Comput Comput Assist Interv ; 14228: 249-259, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38515783

RESUMEN

In cochlear implant (CI) procedures, an electrode array is surgically inserted into the cochlea. The electrodes are used to stimulate the auditory nerve and restore hearing sensation for the recipient. If the array folds inside the cochlea during the insertion procedure, it can lead to trauma, damage to the residual hearing, and poor hearing restoration. Intraoperative detection of such a case can allow a surgeon to perform reimplantation. However, this intraoperative detection requires experience and electrophysiological tests sometimes fail to detect an array folding. Due to the low incidence of array folding, we generated a dataset of CT images with folded synthetic electrode arrays with realistic metal artifact. The dataset was used to train a multitask custom 3D-UNet model for array fold detection. We tested the trained model on real post-operative CTs (7 with folded arrays and 200 without). Our model could correctly classify all the fold-over cases while misclassifying only 3 non fold-over cases. Therefore, the model is a promising option for array fold detection.

8.
Int J Biol Macromol ; 242(Pt 2): 124859, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37187418

RESUMEN

Patients with Alzheimer's disease (AD) display both peripheral tissue and brain insulin resistance, the later could be a potential risk factor for cognitive dysfunction. While certain degree of inflammation is required for inducing insulin resistance, underlying mechanism(s) remains unclear. Evidence from diverse research domains suggest that elevated intracellular fatty acids of de novo pathway can induce insulin resistance even without triggering inflammation; however, the effect of saturated fatty acids (SFAs) could be detrimental due the development of proinflammatory cues. In this context, evidence suggest that while lipid/fatty acid accumulation is a characteristic feature of brain pathology in AD, dysregulated de novo lipogenesis could be a potential source for lipid/fatty acid accumulation. Therefore, therapies aimed at regulating de novo lipogenesis could be effective in improving insulin sensitivity and cognitive function in patients with AD.


Asunto(s)
Enfermedad de Alzheimer , Resistencia a la Insulina , Humanos , Resistencia a la Insulina/fisiología , Lipogénesis/fisiología , Hígado , Enfermedad de Alzheimer/metabolismo , Ácidos Grasos/metabolismo , Inflamación/patología
9.
World J Psychiatry ; 12(6): 827-842, 2022 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-35978970

RESUMEN

BACKGROUND: Insulin resistance (IR) and impaired energy expenditure (IEE) are irreparable metabolic comorbidities in schizophrenia. Although mechanism(s) underlying IR and IEE remains unclear, leptin and fatty acid signaling, which has profound influence on insulin secretion/sensitivity, glucose metabolism and energy expenditure, could be disrupted. However, no association of plasma leptin with erythrocyte membrane fatty acids, body mass index (BMI), and psychotic symptoms in the same cohort of untreated patients with first-episode psychosis (FEP) or medicated patients with chronic schizophrenia (CSZ) is presented before. These studies are crucial for deciphering the role of leptin and fatty acids in the development of IR and IEE in schizophrenia. AIM: To determine the association between plasma leptin, erythrocyte membrane fatty acids, particularly, saturated fatty acids (SFAs), BMI and psychotic symptoms in patients with FEP and CSZ. METHODS: In this study, twenty-two drug naive patients with FEP, twenty-one CSZ patients treated with atypical antipsychotic drugs, and fourteen healthy control (CNT) subjects were analyzed. Plasma leptin was measured using sandwich mode enzyme-linked immunosorbent assay. Erythrocyte membrane SFAs were measured using ultrathin capillary gas chromatography. BMI was calculated by using the formula: weight (kg)/height (m2). Psychiatric symptoms were evaluated at baseline using brief psychiatric rating scale (BPRS), and positive and negative syndrome scale (PANSS). The total BPRS scores, positive and negative symptom scores (PANSS-PSS and PANSS-NSS, respectively) were recorded. Pearson correlation coefficient (r) analyses were performed to find the nature and strength of association between plasma leptin, PANSS scores, BMI and SFAs, particularly, palmitic acid (PA). RESULTS: In patients with FEP, plasma leptin not BMI was significantly lower (P = 0.034), whereas, erythrocyte membrane SFAs were significantly higher (P < 0.005) compared to the CNT subjects. Further, plasma leptin showed negative correlation with erythrocyte membrane SFAs-PA (r = -0.4972, P = 0.001), PANSS-PSS (r = -0.4034, P = 0.028), and PANSS-NSS (r = -0.3487, P = 0.048). However, erythrocyte membrane SFAs-PA showed positive correlation with PANSS-PSS (r = 0.5844, P = 0.0034) and PANSS-NSS (r = 0.5380, P = 0.008). In CSZ patients, plasma leptin, BMI, and erythrocyte membrane SFAs, all were significantly higher (P < 0.05) compared to the CNT subjects. Plasma leptin showed positive correlation with BMI (r = 0.312, P = 0.032) but not with PANSS scores or erythrocyte membrane SFAs-PA. However, erythrocyte membrane SFAs-PA showed positive correlation with PANSS-NSS only (r = 0.4729, P = 0.031). Similar changes in the plasma leptin and erythrocyte membrane SFAs have also been reported in individuals at ultra-high risk of developing psychosis; therefore, the above findings suggest that leptin-fatty acid biosynthesis could be disrupted before the onset of psychosis in schizophrenia. CONCLUSION: Disrupted leptin-fatty acid biosynthesis/signaling could be an early manifestation of metabolic comorbidities in schizophrenia. Large-scale studies are warranted to validate the above findings.

10.
Neurosci Biobehav Rev ; 143: 104919, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36270454

RESUMEN

Insulin resistance may precede the onset of psychosis in schizophrenia; however, the underlying mechanism remains unclear. While certain degree of inflammation is required for triggering insulin resistance, fatty acid accumulation is a crucial step in inflammation. And while all fatty acids can induce insulin resistance, effect of saturated fatty acids (SFAs) could be detrimental due to increase in oxidative stress and development of various inflammatory cues. Intriguingly, evidence suggest that while polyunsaturated fatty acids are reduced, SAFs are increased in the membrane phospholipids from patients with first-episode psychosis. This could be a result of enhanced de novo lipogenesis (DNL) because; antipsychotic treatment further deteriorates insulin resistance, increases DNL and SAF levels as evident by increase in obesity. Therefore, therapies targeting DNL or inflammation may reduce insulin resistance in schizophrenia. In this context, adjunctive treatment with certain anti-inflammatory agents, which seem to reduce DNL/SFAs levels, has shown significant improvement in cognitive and psychotic symptoms; however, its effect on insulin resistance in schizophrenia remain to be documented. In this regard, further large-scale clinical trials are warranted.


Asunto(s)
Resistencia a la Insulina , Trastornos Psicóticos , Humanos , Lipogénesis , Hígado/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/metabolismo
11.
Am J Physiol Heart Circ Physiol ; 298(2): H652-8, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19966052

RESUMEN

Inflammatory bowel disease and arthritis are associated with contact activation that results in cleavage of kininogen to form high molecular weight kininogen (HKa) and bradykinin. We have previously demonstrated that HKa can stimulate inflammatory cytokine and chemokine secretion from human monocytes. We now show that HKa can upregulate tissue factor antigen and procoagulant activity on human monocytes as a function of time (1-4 h) and HKa concentration (75-900 nM). The amino acid sequence responsible to block HKa effects is G440-H455. The HKa receptor macrophage-1 (Mac-1; CD11b18) is the binding site as shown by inhibition by a monoclonal antibody to CD11b/18. Chemical inhibitors of JNK, ERK, and p38 signaling pathways block cell signaling, as does an inhibitor to the transcription factor NF-kappaB. A combination of monoclonal antibodies to TNF-alpha and IL-1beta but neither alone inhibited the HKa induction of tissue factor. These results suggest that HKa mimics LPS by triggering a paracrine pathway in monocytes that depends on TNF-alpha and IL-1beta. Antibodies to kininogen or peptidomimetics might be a useful and safe therapy in inflammatory diseases or sepsis involving cytokines.


Asunto(s)
Interleucina-1beta/metabolismo , Quininógeno de Alto Peso Molecular/farmacología , Monocitos/metabolismo , Tromboplastina/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Interleucina-1beta/inmunología , Quininógeno de Alto Peso Molecular/metabolismo , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Monocitos/citología , Monocitos/efectos de los fármacos , FN-kappa B/metabolismo , ARN Mensajero/metabolismo , Tromboplastina/genética , Factores de Tiempo , Factor de Necrosis Tumoral alfa/inmunología , Regulación hacia Arriba/fisiología
12.
J Med Imaging (Bellingham) ; 7(3): 031504, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32509912

RESUMEN

Purpose: Cochlear implants (CIs) use an array of electrodes surgically threaded into the cochlea to restore hearing sensation. Techniques for predicting the insertion depth of the array into the cochlea could guide surgeons toward more optimal placement of the array to reduce trauma and preserve the residual hearing. In addition to the electrode array geometry, the base insertion depth (BID) and the cochlear size could impact the overall array insertion depth. Approach: We investigated using these measurements to develop a linear regression model that can make preoperative or intraoperative predictions of the insertion depth of lateral wall CI electrodes. Computed tomography (CT) images of 86 CI recipients were analyzed. Using previously developed automated algorithms, the relative electrode position inside the cochlea was measured from the CT images. Results: A linear regression model is proposed for insertion depth prediction based on cochlea size, array geometry, and BID. The model is able to accurately predict angular insertion depths with a standard deviation of 41 deg and absolute deviation error of 32 deg. Conclusions: Surgeons may use this model for patient-customized selection of electrode array and/or to plan a BID for a given array that minimizes the likelihood of causing trauma to regions of the cochlea where residual hearing exists.

13.
Recent Pat Nanotechnol ; 14(3): 239-249, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32167434

RESUMEN

BACKGROUND: The ability to form biofilm and produce several virulence factors has caused numerous human pathogens to become tremendously resistant towards traditional antibiotic treatments, thus, new alternative strategies are urgently in demand. One of the strategies that have recently been developed involves the application of metallic Nanoparticles (NPs). Up to the present, promising results in terms of antimicrobial and antibiofilm activities have been observed in a wide range of metal NPs. METHODS: The present study has selected three metal oxides such as ZnO, SnO2 and CeO2 NPs to comparatively investigate their antibiofilm and antibacterial properties against two Gram-positive human pathogens, which are Listeria monocytogenes and Staphylococcus aureus. RESULTS: The anti-biofilm activities of ZnO, SnO2 and CeO2 NPs against S. aureus and L. monocytogenes were assayed by crystal violet staining and confirmed by microscopic visualization using SEM. The synthesis of amyloid protein by S. aureus and exopolysaccharide by L. monocytogenes in the presence of ZnO, SnO2 and CeO2 NPs was evaluated by Congo red assay. DISCUSSION: Results have shown that ZnO, SnO2 and CeO2 NPs effectively inhibited biofilm formation of both L. monocytogenes and S. aureus. The microscopic analysis also confirmed the antibiofilm activity of these NPs. It was also found that only ZnO NPs inhibited cell growth as well as the production of amyloid protein in S. aureus. CONCLUSION: Overall, these results indicated that ZnO, SnO2 and CeO2 NPs can be considered as potential agents for treating the infections caused by L. monocytogenes and S. aureus, especially those associated with biofilm formation. Based on the present study, further studies are required to understand their mechanisms at both phenotypic and molecular levels, as well as their in vivo cytotoxicity, thereby enabling the applications of these metal oxide NPs in biomedical fields and food industry.


Asunto(s)
Biopelículas/efectos de los fármacos , Cerio/farmacología , Listeria monocytogenes/fisiología , Nanopartículas del Metal/química , Staphylococcus aureus/fisiología , Compuestos de Estaño/farmacología , Óxido de Zinc/farmacología , Humanos , Listeria monocytogenes/efectos de los fármacos , Listeria monocytogenes/ultraestructura , Nanopartículas del Metal/ultraestructura , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/ultraestructura , Pruebas de Toxicidad
14.
Endocrinology ; 149(1): 367-79, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17901229

RESUMEN

The purpose of this study was to enhance our understanding of the mechanisms of neuronal death after focal cerebral ischemia and the neuroprotective effects of tamoxifen (TMX). The phosphorylation state of 31 protein kinases/signaling proteins and superoxide anion (O(2)(-)) production in the contralateral and ipsilateral cortex was measured after permanent middle cerebral artery occlusion (pMCAO) in ovariectomized rats treated with placebo or TMX. The study revealed that pMCAO modulated the phosphorylation of a number of kinases/proteins in the penumbra at 2 h after pMCAO. Of significant interest, phospho-ERK1/2 (pERK1/2) was elevated significantly after pMCAO. TMX attenuated the elevation of pERK1/2, an effect correlated with reduced infarct size. In situ detection of O(2)(-) production showed a significant elevation at 1-2 h after pMCAO in the ischemic cortex with enhanced oxidative damage detected at 24 h. ERK activation may be downstream of free radicals, a suggestion supported by the findings that cells positive for O(2)(-) had high pERK activation and that a superoxide dismutase (SOD) mimetic, tempol, significantly attenuated pERK activation after MCAO. TMX treatment significantly reduced the MCAO-induced elevation of O(2)(-) production, oxidative damage, and proapoptotic caspase-3 activation. Additionally, pMCAO induced a significant reduction in the levels of manganese SOD (MnSOD), which scavenge O(2)(-), an effect largely prevented by TMX treatment, thus providing a potential mechanistic basis for the antioxidant effects of TMX. As a whole, these studies suggest that TMX neuroprotection may be achieved via an antioxidant mechanism that involves enhancement of primarily MnSOD levels, with a corresponding reduction of O(2)(-) production, and downstream kinase and caspase-3 activation.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Fosfotransferasas/metabolismo , Superóxido Dismutasa/metabolismo , Superóxidos/metabolismo , Tamoxifeno/farmacología , Tamoxifeno/uso terapéutico , Animales , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Encéfalo/metabolismo , Isquemia Encefálica/patología , Caspasa 3/metabolismo , Citoprotección/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Femenino , Infarto de la Arteria Cerebral Media/patología , Peroxidación de Lípido/efectos de los fármacos , Mitocondrias/enzimología , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
15.
Neurosignals ; 16(2-3): 140-53, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18253054

RESUMEN

Estrogen has multiple actions in the brain to modulate homeostasis, synaptic plasticity/cognition and neuroprotection. While many of these actions undoubtedly involve mediation via the classical genomic mechanism of regulation of transcription of genes via estrogen nuclear receptors, there has been growing interest in the rapid nongenomic effects of estrogen and the role they may play in the neural actions of estrogen. In this review, we will focus on these rapid nongenomic actions of estrogen in the brain and discuss the potential physiological significance of these actions. The evidence for rapid estrogen regulation of cell signaling pathways, including calcium, ion channel and kinase signaling pathways in the brain will be reviewed, as will evidence derived from plasma-membrane impermeable estrogen-peptide conjugates in the regulation of these cell signaling pathways. Evidence supporting classical and nonclassical estrogen receptor localization to the plasma membrane of neurons will also be reviewed, including the putative new membrane estrogen G-protein-coupled receptor, GPR30. Precisely how membrane estrogen receptors couple to kinase signaling pathways is unclear, but we will discuss the latest findings on estrogen receptor-interacting scaffold proteins, such as MNAR/PELP1, striatin and p130Cas, which are capable of linking estrogen receptors and kinases such as Src and PI3K, to potentially mediate estrogen-induced kinase signaling. Finally, we will review the growing evidence that rapid membrane-mediated effects of estrogen play an important physiological role in the neural actions of estrogen in the brain, including estrogen feedback control and modulation of homeostasis, regulation of synaptic plasticity/cognition, and estrogen-mediated neuroprotection.


Asunto(s)
Encéfalo/fisiología , Estrógenos/fisiología , Receptores de Estrógenos/fisiología , Transducción de Señal/fisiología , Animales , Encéfalo/metabolismo , Humanos , Plasticidad Neuronal/fisiología , Factores de Tiempo
16.
Int J Endocrinol ; 2018: 9516592, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30402099

RESUMEN

Accumulating data from various clinical trial studies suggests that adjuvant therapy with ovarian hormones (estrogens) could be effective in reducing cognitive deficit and psychopathological symptoms in women with psychiatric disorders. However, estrogen therapy poses serious limitations and health issues including feminization in men and increased risks of thromboembolism, hot flashes, breast hyperplasia, and endometrium hyperplasia when used for longer duration in older women (aged ≥ 60 years) or in women who have genetic predispositions. On the other hand, selective estrogen receptor modulators (SERMs), which may (or may not) carry some risks of hot flashes, thromboembolism, breast hyperplasia, and endometrial hyperplasia, are generally devoid of feminization effect. In clinical trial studies, adjuvant therapy with tamoxifen, a triphenylethylene class of SERM, has been found to reduce the frequency of manic episodes in patients with bipolar disorder, whereas addition of raloxifene, a benzothiophene class of SERM, to regular doses of antipsychotic drugs has been found to reduce cognitive deficit and psychological symptoms in men and women with schizophrenia, including women with treatment refractory psychosis. These outcomes together with potent neurocognitive, neuroprotective, and cardiometabolic properties suggest that SERMs could be the potential targets for designing effective and safer therapies for psychiatric disorders.

17.
Curr Pharm Biotechnol ; 19(8): 631-643, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30152281

RESUMEN

BACKGROUND: A novel strategy has been adapted to combat the threat caused by biofilm forming-pathogenic bacteria in our environments. It involves the synthesis of antibiofilm compounds biologically (metabolites from animals, microbes and plants) and chemically. As a result of extensive research, a significant number of antimicrobial compounds and biofilm inhibitors have been isolated and characterized from different biological and chemical sources. However, lots of limitations such as poor delivery, water-insolubility, stability, expulsion by efflux pumps, and the development of acquired resistance due to long-term exposure have been associated with these compounds. METHODS: Conjugation or encapsulation of these antibiofilm drugs with different biocompatible, biodegradable, chemically and thermally stable nanomaterials results in enhanced efficiency of biofilm inhibition. RESULTS AND CONCLUSION: This review article evaluates the current impact of antibiofilm drugs including its delivery, efficiency of blocking cell attachment and molecular mechanisms of action that is conjugated or encapsulated with different types of biocompatible nanomaterials. It will lead to a better understanding of the antibiofilm drugs and their role in combating biofilms. It will also open new doors for the application of immobilized antibiofilm drugs.


Asunto(s)
Antibacterianos/administración & dosificación , Biopelículas/efectos de los fármacos , Portadores de Fármacos/administración & dosificación , Nanoestructuras/administración & dosificación , Animales , Antibacterianos/química , Antibacterianos/farmacocinética , Antiinfecciosos/administración & dosificación , Antiinfecciosos/química , Antiinfecciosos/farmacocinética , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Biopelículas/crecimiento & desarrollo , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Humanos , Nanoestructuras/química , Preparaciones Farmacéuticas/administración & dosificación , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/metabolismo , Extractos Vegetales/administración & dosificación , Extractos Vegetales/química , Extractos Vegetales/farmacocinética
18.
Arterioscler Thromb Vasc Biol ; 26(10): 2260-6, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16902163

RESUMEN

OBJECTIVE: Plasma high-molecular-weight kininogen (HK) is cleaved in inflammatory diseases by kallikrein to HKa with release of bradykinin (BK). We postulated a direct link between HKa and cytokine/chemokine release. METHODS AND RESULTS: HKa, but not BK, releases cytokines tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6, and chemokines IL-8 and MCP-1 from isolated human mononuclear cells. At a concentration of 600 nM, glutathione-S-transferase (GST) fusion proteins of kininogen domain 3 (D3), a fragment of domain 3, E7P (aaG255-Q292), HK domain 5 (D5), the D5 recombinant peptides HG (aa K420-D474) and HGK (aa H475-S626) stimulated secretion of IL-1beta from mononuclear cells. Monoclonal antibodies (MAbs) specific for D5 or specific for D3 blocked release of IL-1beta by HKa, supporting the importance of both domains. Antibodies to HK receptors on leukocytes including Mac-1, LFA-1, uPAR, and C1qR inhibited IL-1beta secretion induced by tKa 98%, 89%, 85%, and 62%, respectively. Fractionation of mononuclear cells identified the responsible cell, a blood monocyte. Inhibitors of signaling pathways NFkB, JNK, and p38 but not extracellular signal-regulated kinase (ERK) decreased cytokine release from mononuclear cells. HKa increased the synthesis of IL-1beta as deduced by an increase of IL-1beta mRNA at 1 to 2 hours. CONCLUSIONS: HKa domains 3 and 5 may contribute to the pathogenesis of inflammatory diseases by releasing IL-1beta from human monocytes using intracellular signaling pathways initiated by uPAR, beta2 integrins and gC1qR.


Asunto(s)
Quimiocinas/metabolismo , Citocinas/metabolismo , Quininógeno de Alto Peso Molecular/farmacología , Antígeno de Macrófago-1/metabolismo , Glicoproteínas de Membrana/metabolismo , Monocitos/metabolismo , Receptores de Superficie Celular/metabolismo , Receptores de Complemento/metabolismo , Anticuerpos Monoclonales/farmacología , Antígeno CD11a/inmunología , Humanos , Interleucina-1/antagonistas & inhibidores , Interleucina-1/genética , Interleucina-1/metabolismo , Quininógeno de Alto Peso Molecular/inmunología , Quininógeno de Alto Peso Molecular/metabolismo , Antígeno de Macrófago-1/inmunología , Glicoproteínas de Membrana/inmunología , Proteínas Quinasas Activadas por Mitógenos/fisiología , FN-kappa B/fisiología , Concentración Osmolar , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/farmacología , ARN Mensajero/metabolismo , Receptores de Superficie Celular/inmunología , Receptores de Complemento/inmunología , Receptores del Activador de Plasminógeno Tipo Uroquinasa , Factores de Tiempo
19.
Steroids ; 72(5): 381-405, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17379265

RESUMEN

Estrogen is an important hormone signal that regulates multiple tissues and functions in the body. This review focuses on the neurotrophic and neuroprotective actions of estrogen in the brain, with particular emphasis on estrogen actions in the hippocampus, cerebral cortex and striatum. Sex differences in the risk, onset and severity of neurodegenerative disease such as Alzheimer's disease, Parkinson's disease and stroke are well known, and the potential role of estrogen as a neuroprotective factor is discussed in this context. The review assimilates a complex literature that spans research in humans, non-human primates and rodent animal models and attempts to contrast and compare the findings across species where possible. Current controversies regarding the Women's Health Initiative (WHI) study, its ramifications, concerns and the new studies needed to address these concerns are also addressed. Signaling mechanisms underlying estrogen-induced neuroprotection and synaptic plasticity are reviewed, including the important concepts of genomic versus nongenomic mechanisms, types of estrogen receptor involved and their subcellular targeting, and implicated downstream signaling pathways and mediators. Finally, a multicellular mode of estrogen action in the regulation of neuronal survival and neurotrophism is discussed, as are potential future directions for the field.


Asunto(s)
Estrógenos/metabolismo , Genoma Humano , Enfermedades Neurodegenerativas/metabolismo , Plasticidad Neuronal , Fármacos Neuroprotectores/metabolismo , Transducción de Señal , Animales , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Estrógenos/uso terapéutico , Genoma Humano/efectos de los fármacos , Humanos , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedades Neurodegenerativas/genética , Plasticidad Neuronal/efectos de los fármacos , Plasticidad Neuronal/genética , Fármacos Neuroprotectores/uso terapéutico , Primates , Receptores de Estrógenos/genética , Receptores de Estrógenos/metabolismo , Roedores , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Tropismo/efectos de los fármacos , Tropismo/genética
20.
J Am Coll Cardiol ; 46(4): 707-13, 2005 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-16098440

RESUMEN

OBJECTIVES: The purpose of this study was to test the hypothesis that activated monocytes with soluble plasma tissue factor (pTF) activate factors VII and X to generate thrombin. BACKGROUND: Despite heparin, thrombin is progressively generated during cardiac surgery with cardiopulmonary bypass (CPB), produces intravascular fibrin and fibrinolysis, and causes serious thromboembolic and nonsurgical bleeding complications. Thrombin is primarily produced in the surgical wound, but mechanisms are unclear. METHODS: In 13 patients, interactions of mononuclear cells, platelets, pTF, and pTF fractions to activate factors VII and X were evaluated in pre-bypass, perfusate, and pericardial wound blood before and during CPB. RESULTS: Monocytes are activated in wound, but not in pre-bypass or perfusate plasma (monocyte chemotactic protein-1 = 29.5 +/- 2.1 pmoles/l vs. 2.8 +/- 1.2 pmoles/l and 3.3 +/-1.4 pmoles/l, respectively). Wound pTF is substantially elevated compared to other locations (3.64 +/- 0.45 pmoles/l vs. 0.71 +/- 0.65 pmoles/l and 1.31 +/- 1.4 pmoles/l). Supernatant wound pTF contains 81.7% of TF antigen; wound microparticle pTF contains 18.3%. Wound monocytes and all C5a-stimulated monocytes (but not activated platelets) completely convert factor VII to factor VIIa with wound pTF. Activated monocytes more efficiently activate factor X with wound supernatant TF/factor VII(VIIa) complex than with wound microparticle TF/factor VII(fVIIa). The correlation coefficient (r) between wound thrombin generation (F1.2) and wound pTF concentration is 0.944 (p = 0.0004). CONCLUSIONS: During cardiac surgery with CPB, wound monocytes plus wound pTF or wound microparticle-free supernatant pTF preferentially accelerate activation of factor VII and factor X. This system represents a novel mechanism for thrombin generation via the TF coagulation pathway.


Asunto(s)
Coagulación Sanguínea/fisiología , Puente Cardiopulmonar/efectos adversos , Factor VII/biosíntesis , Factor X/biosíntesis , Monocitos/fisiología , Plasma/química , Hemorragia Posoperatoria/fisiopatología , Trombina/biosíntesis , Tromboplastina/análisis , Anciano , Anciano de 80 o más Años , Factores de Coagulación Sanguínea/fisiología , Western Blotting , Factor VII/análisis , Factor X/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , Cicatrización de Heridas
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