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1.
Neurocrit Care ; 41(2): 665-680, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38724864

RESUMO

BACKGROUND: Sovateltide (IRL-1620), an endothelin B receptor agonist, has previously demonstrated neuroprotective and neuroregenerative effects in animal models of acute ischemic stroke. Recently, clinical trials indicated that it could also be effective in humans with stroke. Here, we systematically investigate whether IRL-1620 may be used for the treatment of ischemia-induced brain injury. METHODS: A systematic review was performed following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. MEDLINE (PubMed) and Scopus databases were searched for eligible studies up to December 2022. The databases ClinicalTrials.gov and Pharmazz Inc. were screened for unpublished or ongoing trials. Only studies in English were evaluated for eligibility. Meta-analysis of the included studies was also conducted. RESULTS: Finally, seven studies were included in the review, all in animal rat models because of scarcity of clinical trials. Six studies, all in middle cerebral artery occlusion (MCAO) models, were selected for meta-analysis. In the two studies assessing mortality, no deaths were reported in the IRL-1620 group 24 h after MCAO, whereas the vehicle group had almost a five times higher mortality risk (risk ratio 5.3, 95% confidence interval 0.7-40.1, I2 = 0%). In all five studies evaluating outcome on day 7 after MCAO, IRL-1620 was associated with statistically significantly lower neurological deficit and improved motor performance compared with the vehicle. Infract volume, differentiation potential of neuronal progenitor cells, and mitochondrial fate also improved with IRL-1620 administration. CONCLUSIONS: According to the above, in animal MCAO models, IRL-1620 enhanced neurogenesis and neuroprotection and improved outcome. Future studies are needed to expand our understanding of its effects in human study participants with acute ischemic stroke as well as in other common causes of cerebral ischemia including cardiac arrest.


Assuntos
Fármacos Neuroprotetores , Animais , Fármacos Neuroprotetores/farmacologia , Isquemia Encefálica/tratamento farmacológico , Endotelinas/farmacologia , Ratos , Infarto da Artéria Cerebral Média/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Fragmentos de Peptídeos
2.
J Clin Med ; 12(20)2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37892791

RESUMO

Neonatal hypoxic-ischemic encephalopathy (HIE) is a condition that results in brain damage in newborns due to insufficient blood and oxygen supply during or after birth. HIE is a major cause of neurological disability and mortality in newborns, with over one million neonatal deaths occurring annually worldwide. The severity of brain injury and the outcome of HIE depend on several factors, including the cause of oxygen deprivation, brain maturity, regional blood flow, and maternal health conditions. HIE is classified into mild, moderate, and severe categories based on the extent of brain damage and resulting neurological issues. The pathophysiology of HIE involves different phases, including the primary phase, latent phase, secondary phase, and tertiary phase. The primary and secondary phases are characterized by episodes of energy and cell metabolism failures, increased cytotoxicity and apoptosis, and activated microglia and inflammation in the brain. A tertiary phase occurs if the brain injury persists, characterized by reduced neural plasticity and neuronal loss. Understanding the cellular and molecular aspects of the different phases of HIE is crucial for developing new interventions and therapeutics. This review aims to discuss the pathophysiology of HIE, therapeutic hypothermia (TH), the only approved therapy for HIE, ongoing developments of adjuvants for TH, and potential future drugs for HIE.

3.
Biochem Genet ; 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37792224

RESUMO

Colon cancer is one of the malignant tumors with high morbidity, lethality, and prevalence across global human health. Molecular biomarkers play key roles in its prognosis. In particular, immune-related lncRNAs (IRL) have attracted enormous interest in diagnosis and treatment, but less is known about their potential functions. We aimed to investigate dysfunctional IRL and construct a risk model for improving the outcomes of patients. Nineteen immune cell types were collected for identifying house-keeping lncRNAs (HKLncRNA). GSE39582 and TCGA-COAD were treated as the discovery and validation datasets, respectively. Four machine learning algorithms (LASSO, Random Forest, Boruta, and Xgboost) and a Gaussian mixture model were utilized to mine the optimal combination of lncRNAs. Univariate and multivariate Cox regression was utilized to construct the risk score model. We distinguished the functional difference in an immune perspective between low- and high-risk cohorts calculated by this scoring system. Finally, we provided a nomogram. By leveraging the microarray, sequencing, and clinical data for immune cells and colon cancer patients, we identified the 221 HKLncRNAs with a low cell type-specificity index. Eighty-seven lncRNAs were up-regulated in the immune compared to cancer cells. Twelve lncRNAs were beneficial in improving performance. A risk score model with three lncRNAs (CYB561D2, LINC00638, and DANCR) was proposed with robust ROC performance on an independent dataset. According to immune-related analysis, the risk score is strongly associated with the tumor immune microenvironment. Our results emphasized IRL has the potential to be a powerful and effective therapy for enhancing the prognostic of colon cancer.

4.
Transfus Apher Sci ; 62(5): 103768, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37599155

RESUMO

INTRODUCTION: The direct antiglobulin test (DAT) identifies immunoglobulin IgG and/or complement onthe red blood cell surface, allowing discrimination between immune and non-immunehemolysis. When the DAT is negative but there is clinical suspicion for immunehemolysis, an enhanced DAT can be sent to an immunohematology referencelaboratory (IRL). METHODOLOGY: This retrospective study assessed the volume of enhanced DATs at a large tertiarycare center and evaluated their impact on patient care. Enhanced DATs were sent on21 adult patients (January 2019 - January 2021) at the University of Pittsburgh MedicalCenter and Allegheny Health Network. Laboratory and clinical data were collected andanalyzed. RESULTS: Four out of 21 patients had positive tests (DAT and other serologic tests) at the localIRL. Enhanced DAT testing yielded positive results in an additional 5 patients butnegative or invalid results for 2 patients. High-dose steroid therapy was started in 12patients prior to receipt of enhanced DAT results. Enhanced DAT testing was sent amedian of 5 days after initiation of steroid therapy. For the patients trialed on steroids,the enhanced DAT results impacted medical decision-making in only 3 patients, and inonly one of those patients was the enhanced DAT positive despite a negative DAT at alocal IRL. In the non-steroid treated patients, enhanced DAT results did not contributeto clinical decision-making. CONCLUSION: Enhanced DATs generally did not impact medical decision-making in adults withhemolytic anemia.


Assuntos
Doença de Alzheimer , Anemia Hemolítica Autoimune , Humanos , Adulto , Estudos Retrospectivos , Teste de Coombs/métodos , Eritrócitos/metabolismo , Esteroides
6.
Mult Scler ; 28(14): 2202-2211, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36000485

RESUMO

BACKGROUND: Iron rims (IRs) surrounding white matter lesions (WMLs) are suggested to predict a more severe disease course. Only small longitudinal cohorts of patients with and without iron rim lesions (IRLs) have been reported so far. OBJECTIVE: To assess whether the presence and number of IRLs in patients with clinically isolated syndrome (CIS) and multiple sclerosis (MS) are associated with long-term disability or progressive disease. METHODS: Ninety-one CIS/MS patients were recruited between 2008 and 2013 and scanned with 7 T magnetic resonance imaging (MRI). Expanded Disability Status Scale (EDSS) was used to calculate Age-related Multiple Sclerosis Severity Score (ARMSS) at the time of scan and at the latest clinical follow-up after 9 years. WMLs were assessed for the presence of IRL using Susceptibility weighted imaging (SWI)-filtered phase images. RESULTS: In all, 132 IRLs were detected in 42 patients (46%); 9% of WMLs had IRs; 54% of the cohort had no rims, 30% had 1-3 rims and 16% had ⩾4. Patients with IRL had a higher EDSS and ARMSS. Presence of IRL was also a predictor of long-term disability, especially in patients with ⩾4 IRLs. IRLs have a greater impact on disability compared to the WML number and volume. CONCLUSION: The presence and number of perilesional IR on MRI hold prognostic value for long-term clinical disability in MS.


Assuntos
Doenças Desmielinizantes , Esclerose Múltipla , Humanos , Criança , Esclerose Múltipla/diagnóstico por imagem , Ferro , Estudos Longitudinais , Doenças Desmielinizantes/diagnóstico por imagem , Progressão da Doença
7.
World J Surg Oncol ; 20(1): 164, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35606755

RESUMO

BACKGROUND: Rapid advances in transcriptomic profiles have resulted in recognizing IRLs (immune-related long noncoding RNAs), as modulators of the expression of genes related to immune cells that mediate immune inhibition as well as immune stimulatory, indicating LncRNAs play fundamental roles in immune modulation. Hence, we establish an IRL classifier to precisely predict prognosis and immunotherapeutic efficiency in laryngeal squamous cell carcinoma (LSCC). METHODS: LSCC RNA-seq (RNA sequencing) datasets, somatic mutation data, and corresponding clinicopathologic information were acquired from TCGA (the Cancer Genome Atlas) and Gene Expression Omnibus (GEO) databases. Spearman correlation analysis identified LncRNAs associated with immune-related genes (IRG). Based on Lasso penalized regression and random forest (RF), we constructed an IRL classifier associated with prognosis. GEO database was utilized to validate the IRL classifier. The predictive precision and clinical application of the IRL classifier were assessed and compared to clinicopathologic features. The immune cell infiltration of LSCC was calculated via CIBERSORTx tools and ssGSEA (single-sample gene set enrichment analysis). Then, we systematically correlated the IRL classifier with immunological characteristics from multiple perspectives, such as immune-related cells infiltrating, tumor microenvironment (TME) scoring, microsatellite instability (MSI), tumor mutation burden (TMB), and chemokines. Finally, the TIDE (tumor immune dysfunction and exclusion) algorithm was used to predict response to immunotherapy. RESULTS: Based on machine learning approach, three prognosis-related IRLs (BARX1-DT, KLHL7-DT, and LINC02154) were selected to build an IRL classifier. The IRL classifier could availably classify patients into the low-risk and high-risk groups based on the different endpoints, including recurrence-free survival (RFS) and overall survival (OS). In terms of predictive ability and clinical utility, the IRL classifier was superior to other clinical characteristics. Encouragingly, similar results were observed in the GEO databases. Immune infiltration analysis displayed immune cells that are significantly richer in low-risk group, CD8 T cells and activated NK cells via CIBERSORTx algorithm as well as activated CD8 T cell via ssGSEA. Additionally, compared with the high-risk group, immune score, CD8 T effector was higher in the low-risk group, yet stromal score, score of p53 signaling pathway and TGFher in the Tx algorithm, was lower in the low-risk group. Corresponding results were confirmed in GEO dataset. Finally, TIDE analysis uncovered that the IRL classifier may be effectually predict the clinical response of immunotherapy in LSCC. CONCLUSION: Based on BARX1-DT, KLHL7-DT, and LINC02154, the IRL classifier was established, which can be used to predict the prognosis, immune infiltration status, and immunotherapy response in LSCC patients and might facilitate personalized counseling for immunotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço , RNA Longo não Codificante , Biomarcadores Tumorais/genética , Humanos , Imunoterapia , Prognóstico , RNA Longo não Codificante/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Microambiente Tumoral
8.
Biosci Rep ; 42(5)2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35438133

RESUMO

The primary objective of this study was to construct an immune-related long noncoding RNAs (IRLs) classifier to precisely predict the prognosis and immunotherapy response of patients with thymic epithelial tumors (TET). Based on univariable Cox regression analysis and Lasso regression, six prognosis-related IRLs (AC004466.3, AC138207.2, AC148477.2, AL450270.1, HOXB-AS1 and SNHG8) were selected to build an IRL classifier. Importantly, results of qRT-PCR validated that higher expression levels of AC138207.2, AC148477.2, AL450270.1 and SNHG8 as well as lower expression levels of AC004466.3, and HOXB-AS1 in TETs samples compared with normal controls. The IRL classifier could effectively classify patients into the low-risk and high-risk groups based on the different survival parameters. In terms of predictive ability and clinical utility, the IRL classifier was superior to Masaoka staging system. Additionally, IRL classifier is significantly associated with immune cells infiltration (dendritic cells, activated CD4 memory T cells and tumor-infiltrating lymphocyte (TIL), T cell subsets in particular), immune microenvironment (immune score and immune checkpoint inhibitors) and immunogenicity (TMB) in TETs, which hints that IRL classifier is tightly correlated with immune characteristics and might guide more effective immunotherapy strategies for TETs patients. Encouragingly, according to TIDE algorithm, there were more immunotherapy responders in the low-risk IRL subgroup and the IRL score was robustly negatively linked to the immunotherapeutic response. To sum up, the IRL classifier was established, which can be used to predict the prognosis, immune infiltration status, immunotherapy response in TETs patients, and may facilitate personalized counseling for immunotherapy.


Assuntos
Neoplasias Epiteliais e Glandulares , RNA Longo não Codificante , Biomarcadores Tumorais/genética , Humanos , Imunoterapia , Neoplasias Epiteliais e Glandulares/diagnóstico , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Epiteliais e Glandulares/terapia , RNA Longo não Codificante/genética , Neoplasias do Timo , Microambiente Tumoral/genética
9.
Int J Mol Sci ; 23(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35328566

RESUMO

Neurological/neurovascular disorders constitute the leading cause of disability and the second leading cause of death globally. Major neurological/neurovascular disorders or diseases include cerebral stroke, Alzheimer's disease, spinal cord injury, neonatal hypoxic-ischemic encephalopathy, and others. Their pathophysiology is considered highly complex and is the main obstacle in developing any drugs for these diseases. In this review, we have described the endothelin system, its involvement in neurovascular disorders, the importance of endothelin B receptors (ETBRs) as a novel potential drug target, and its agonism by IRL-1620 (INN-sovateltide), which we are developing as a drug candidate for treating the above-mentioned neurological disorders/diseases. In addition, we have highlighted the results of our preclinical and clinical studies related to these diseases. The phase I safety and tolerability study of sovateltide has shown it as a safe and tolerable compound at therapeutic dosages. Furthermore, preclinical and clinical phase II studies have demonstrated the efficacy of sovateltide in treating acute ischemic stroke. It is under development as a first-in-class drug. In addition, efficacy studies in Alzheimer's disease (AD), acute spinal cord injury, and neonatal hypoxic-ischemic encephalopathy (HIE) are ongoing. Successful completion of these studies will validate that ETBRs signaling can be an important target in developing drugs to treat neurological/neurovascular diseases.


Assuntos
Doença de Alzheimer , Hipóxia-Isquemia Encefálica , AVC Isquêmico , Traumatismos da Medula Espinal , Doença de Alzheimer/tratamento farmacológico , Humanos , Recém-Nascido , Receptor de Endotelina B
10.
Biochem Biophys Rep ; 29: 101197, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35028438

RESUMO

Lighting conditions may affect the development of retinal degenerative diseases such as macular degeneration. In this study, to determine whether the lighting environment affects the progression of degeneration of retinal ganglion cells (RGCs), we examined glutamate/aspartate transporter (GLAST) heterozygous (GLAST+/-) mice, a mouse model of normal tension glaucoma. GLAST+/- mice were reared under a 12-h light-dark cycle (Light/Dark) or complete darkness (Dark/Dark) condition after birth. The total RGC number in the Dark/Dark group was significantly decreased compared with the Light/Dark group at 3 weeks old, while the number of osteopontin-positive αRGCs were similar in both groups. At 6 and 12 weeks old, the total RGC number were not significantly different in both conditions. In addition, the retinal function examined by multifocal electroretinogram were similar at 12 weeks old. These results suggest that lighting conditions may regulate the progression of RGC degeneration in some types of glaucoma.

11.
Mol Genet Metab Rep ; 27: 100767, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34026550

RESUMO

PURPOSE: Macular structure is poorly evaluated in early-treated phenylketonuria (ETPKU). To evaluate potential changes, we aimed to examine retinas of PKU patients using optical coherence tomography (OCT) with additional OCT angiography (OCTA) and compare the results to healthy controls. METHODS: A total of 100 adults were recruited in this monocentric, case-control study: 50 patients with ETPKU (mean age: 30.66 ± 8.00 years) and 50 healthy controls (mean age: 30.45 ± 7.18 years). Macular thickness, vessel density and flow area of the right eye was assessed with spectral domain OCT angiography SD-OCT(A). Macular microstructural data between the ETPKU and control group was compared. In the ETPKU group, the relationship between visual functional parameters (best corrected visual acuity [VA], spherical equivalent [SE], contrast sensitivity [CS] and near stereoacuity) and microstructural alterations was examined. The dependency of OCT(A) values on serum phenylalanine (Phe) level was analysed. RESULTS: There was significant average parafoveal and perifoveal total retinal layer thinning in ETPKU patients compared to healthy controls (p < 0.016 and p < 0.001, respectively), while the foveal region remained unchanged in the ETPKU group. Whole macular and parafoveal superficial capillary plexus density was significantly decreased in ETPKU compared to controls (p < 0.001). There were no significant differences in the foveal avascular zone, nonflow area, macular superficial and deep capillary plexus between the groups. The temporal parafoveal inner retinal layer thickness was found to negatively correlate with individual Phe levels (r = -0.35, p = 0.042). There was no difference in vascular density and retinal thickness in the subgroup analysis of patients with good therapy adherence compared to patients on a relaxed diet. CONCLUSIONS: Durable elevation in Phe levels are only partially associated with macular retinal structural changes. However, therapy adherence might not influence these ophthalmological complications.

12.
Sci Total Environ ; 743: 140414, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659566

RESUMO

Childhood Pb exposure is associated with a multitude of poor health outcomes. In food-insecure areas, growing fresh produce in backyard gardens or on vacant industrial properties is seen as an option for parents. The question arises, could Pb accumulate in consumable tissues of common produce when grown in metals-rich soils at concentrations that would pose a risk to children. This study investigated factors contributing to the accumulation of Pb in consumable tissues of nine common produce crops grown in metals-rich soils from backyard gardens and a former industrial property. Pb in consumable tissues was directly quantified at concentrations less than 1 µg g-1 via X-ray fluorescence (XRF) using protocols specifically developed for use in plant matrices. The accumulation of Pb in prepared raw consumable tissues in three Pb-rich soils was the greatest in modified taproot crops (mean Pb of 11.8 ± 14.6 µg g-1; turnip, beetroot, radish, carrot), with lesser concentrations in fruits (mean Pb of 2.0 ± 3.0 µg g-1; tomato, pepper), and potatoes (mean Pb of 0.7 ± 1.1 µg g-1). An exposure risk evaluation using the USFDA IRL for Pb indicates that consumption of less than 1 g of certain produce grown in this study, including produce grown in garden soils from residential properties, drastically increases the risk of Pb exposure in children. This study further indicates that the proportion of Pb contributed to the daily body burden in children from food is far greater than previously understood, and in all modeled cases, the contribution of Pb from food on a daily basis far outweighs the contribution of Pb from drinking water. For an average child, after addressing over-riding soil/dust impacts, addressing food quality is critical to minimizing Pb exposure.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Criança , Jardinagem , Humanos , Chumbo , Solo , Verduras
13.
Can J Physiol Pharmacol ; 98(9): 659-666, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32574518

RESUMO

Stimulation of endothelin B receptors by its agonist IRL-1620 (INN, sovateltide) provides neuroprotection and neurological and motor function improvement following cerebral ischemia. We investigated the effect of sovateltide on stem and progenitor cells mediated neural regeneration and its effect on the cerebral tissue repair and restoration of neurological and motor function. Sovateltide (5 µg/kg) was injected intravenously in permanent middle cerebral artery occluded (MCAO) rats at 4, 6, and 8 h at days 0, 3, and 6. Neurological and motor function tests were carried out pre-MCAO and at day 7 post-MCAO. At day 7, significantly reduced expression of neuronal differentiation markers HuC/HuD and NeuroD1 was seen in MCAO + vehicle than sham rats. Sovateltide treatment upregulated HuC/HuD and NeuroD1 compared to MCAO + vehicle and their expression was similar to sham. Expression of stem cell markers Oct 4 and Sox 2 was similar in rats of all of the groups. Significantly reduced infarct volume and DNA damage with recovery of neurological and motor function was observed in sovateltide-treated MCAO rats. These results indicate that sovateltide initiates a regenerative response by promoting differentiation of neuronal progenitors and maintaining stem cells in an equilibrium following cerebral ischemic stroke.


Assuntos
Encéfalo/efeitos dos fármacos , Endotelinas/administração & dosagem , Infarto da Artéria Cerebral Média/tratamento farmacológico , AVC Isquêmico/tratamento farmacológico , Fragmentos de Peptídeos/administração & dosagem , Células-Tronco/efeitos dos fármacos , Animais , Encéfalo/patologia , Diferenciação Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/patologia , Injeções Intravenosas , AVC Isquêmico/etiologia , AVC Isquêmico/patologia , Masculino , Regeneração Nervosa/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Ratos , Receptor de Endotelina B/agonistas , Receptor de Endotelina B/metabolismo , Células-Tronco/patologia
14.
Regul Toxicol Pharmacol ; 111: 104579, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31945454

RESUMO

FDA developed the interim reference level (IRL) for lead of 3 µg/day in children and 12.5 µg/day in women of childbearing age (WOCBA) to better protect the fetus from lead toxicity. These IRLs correspond to a blood lead level (BLL) of 0.5 µg/dL in both populations. The current investigation was performed to determine if the IRL for WOCBA should apply to the general population of adults. A literature review of epidemiological studies was conducted to determine whether a BLL of 0.5 µg/dL is associated with adverse effects in adults. Some studies reported adverse effects over a wide range of BLLs that included 0.5 µg/dL adding uncertainty to conclusions about effects at 0.5 µg/dL; however, no studies clearly identified this BLL as an adverse effect level. Results also showed that the previously developed PTTDI for adults of 75 µg/day lead may not be health protective, supporting use of a lower reference value for lead toxicity in this population group. Use of the 12.5 µg/day IRL as a benchmark for dietary lead intake is one way FDA will ensure that dietary lead intake in adults is reduced.


Assuntos
Exposição Dietética/efeitos adversos , Exposição Dietética/normas , Chumbo/administração & dosagem , Chumbo/efeitos adversos , Adulto , Poluentes Ambientais , Humanos , Chumbo/sangue
15.
Regul Toxicol Pharmacol ; 110: 104516, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31707132

RESUMO

Reducing lead exposure is a public health priority for the US Food and Drug Administration as well as other federal agencies. The goals of this research were to 1) update the maximum daily dietary intake of lead from food, termed an interim reference level (IRL), for children and for women of childbearing age (WOCBA) and 2) to confirm through a literature review that with the exception of neurodevelopment, which was not evaluated here, no adverse effects of lead consistently occur at the blood lead level (BLL) associated with the IRL. Because no safe level of lead exposure has yet been identified for children's health, the IRLs of 3 µg/day for children and 12.5 µg/day for WOCBA were derived from the Centers for Disease Control and Prevention reference value of 5 µg/dL BLL, the level at which public health actions should be initiated. The literature review showed that no adverse effects of lead consistently occurred at the BLL associated with the IRLs (0.5 µg/dL). The IRLs of 3 µg/day for children and 12.5 µg/day for WOCBA should serve as useful benchmarks in evaluating the potential for adverse effects of dietary lead.


Assuntos
Exposição Dietética/normas , Poluentes Ambientais/normas , Chumbo/normas , Adulto , Criança , Pré-Escolar , Exposição Dietética/prevenção & controle , Poluentes Ambientais/toxicidade , Feminino , Humanos , Lactente , Recém-Nascido , Chumbo/toxicidade , Gravidez , Estados Unidos , United States Food and Drug Administration
16.
Mol Neurobiol ; 55(5): 4297-4310, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28623618

RESUMO

Endothelin-1 (ET-1) has been demonstrated to be a pro-nociceptive as well as an anti-nociceptive agent. However, underlying molecular mechanisms for these pain modulatory actions remain unclear. In the present study, we evaluated the ability of ET-1 to alter the nociceptor excitability using a patch clamp technique in acutely dissociated rat dorsal root ganglion (DRG) neurons. ET-1 produced an increase in threshold current to evoke an action potential (I threshold) and hyperpolarization of resting membrane potential (RMP) indicating decreased excitability of DRG neurons. I threshold increased from 0.25 ± 0.08 to 0.33 ± 0.07 nA and hyperpolarized RMP from -57.51 ± 1.70 to -67.41 ± 2.92 mV by ET-1 (100 nM). The hyperpolarizing effect of ET-1 appears to be orchestrated via modulation of membrane conductances, namely voltage-gated sodium current (I Na) and outward transient potassium current (I KT). ET-1, 30 and 100 nM, decreased the peak I Na by 41.3 ± 6.8 and 74 ± 15.2%, respectively. Additionally, ET-1 (100 nM) significantly potentiated the transient component (I KT) of the potassium currents. ET-1-induced effects were largely attenuated by BQ-788, a selective ETBR blocker. However, a selective ETAR blocker BQ-123 did not alter the effects of ET-1. A selective ETBR agonist, IRL-1620, mimicked the effect of ET-1 on I Na in a concentration-dependent manner (IC50 159.5 ± 92.6 µM). In conclusion, our results demonstrate that ET-1 hyperpolarizes nociceptors by blocking I Na and potentiating I KT through selective activation of ETBR, which may represent one of the underlying mechanisms for reported anti-nociceptive effects of ET-1.


Assuntos
Potenciais de Ação , Endotelina-1/farmacologia , Gânglios Espinais/citologia , Neurônios/metabolismo , Receptor de Endotelina B/metabolismo , Potenciais de Ação/efeitos dos fármacos , Animais , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Células Cultivadas , Antagonistas do Receptor de Endotelina B/farmacologia , Ativação do Canal Iônico/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Nociceptores/metabolismo , Canais de Potássio/metabolismo , Ratos Sprague-Dawley , Canais de Sódio/metabolismo
17.
Life Sci ; 159: 30-33, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26898124

RESUMO

Biased ligands represent a new strategy for the development of more effective and better tolerated drugs. To date there has been a paucity of research exploring the potential of ligands that exhibit either G protein or ß-arrestin pathway selectivity at the endothelin receptors. Re-analysis of data may allow researchers to determine whether there is existing evidence that the endogenous ET peptides or currently available agonists and antagonists exhibit pathway bias in a particular physiological or disease setting and this is explored in the review. An alternative to molecules that bind at the orthosteric site of the ET receptors are cell penetrating peptides that interact with a segment of an intracellular loop of the receptor to modify signalling behaviour. One such peptide IC2B has been shown to have efficacy in a model of pulmonary arterial hypertension. Finally, understanding the molecular pathways that contribute to disease is critical to determining whether biased ligands will provide clinical benefit. The role of ETA signalling in ovarian cancer has been delineated in some detail and this has led to the suggestion that the development of ETA G protein biased agonists or ß-arrestin biased antagonists should be explored.


Assuntos
Antagonistas dos Receptores de Endotelina/farmacologia , Receptores de Endotelina/agonistas , Animais , Humanos , Peptídeos/farmacologia , Receptores de Endotelina/metabolismo
18.
Neuroscience ; 312: 141-52, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26592721

RESUMO

One common feature of most neurodegenerative diseases, including Alzheimer's disease (AD) and stroke, is the death of neuronal cells. Neuronal cell death is associated with apoptosis, generation of reactive oxygen species and oxidative stress. Neuronal cell death pathways can be reversed by endothelin B receptor agonist, IRL-1620, which was found to enhance neuroprotection by promoting vascular and neuronal growth in a rodent stroke model. Previous studies conducted at our institution indicated that the treatment with IRL-1620 significantly improved neurological and motor function while reducing oxidative stress and overall infarct area. IRL-1620 is a hydrophilic, 15 amino acid peptide and has a molecular weight of 1820Da. In this study, we have encapsulated IRL-1620 in PEGylated liposomes in order to enhance its efficacy. Each batch of liposomes encapsulating IRL-1620 was evaluated for particle size, polydispersity index, and charge (zeta potential) over a period of time to determine their stability. A dose-response bar graph was plotted based on the effect of neuroprotection by free IRL-1620 on differentiated neuronal PC-12 cells. The 1nM concentration was found to have the highest cell viability. The liposomes loaded with IRL-1620 were tested on differentiated neuronal PC-12 cells for their neuroprotective ability against apoptosis caused by removal of nerve growth factor (NGF) against free (non-encapsulated) IRL-1620. The liposomal IRL-1620 was found to proliferate the growth of serum-deprived differentiated PC-12 cells significantly (p<0.0001). In the western blot analysis, the expression of the anti-apoptotic marker, BCL-2 was found to be increased, and that of pro-apoptotic marker, BAX was found to be decreased with liposomal IRL-1620. The effects were found to be independent of the NGF levels. Finally the free IRL-1620 was found to cause neuronal outgrowth equivalent to the 75ng/ml NGF treatment.


Assuntos
Endotelinas/administração & dosagem , Endotelinas/farmacologia , Nanotecnologia/métodos , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/farmacologia , Receptor de Endotelina B/agonistas , Animais , Bioensaio , Sobrevivência Celular , Lipossomos , Células PC12 , Polietilenoglicóis , Ratos
19.
J Clin Diagn Res ; 9(11): LC09-12, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26674711

RESUMO

INTRODUCTION: Multidrug resistant tuberculosis (MDR-TB) is caused by Infection with Mycobacterium tuberculosis which is resistant to both isoniazid (INH) and rifampicin (RIF), with or without any other anti tubercular drug. It is caused by resistant mutant strains due to inadequate treatment and poor compliance. Due to time taking conventional diagnostic methods, drug resistant strains continue to spread. Therefore rapid diagnosis and treatment of MDR-TB strains are prerequisites for the worldwide fight against TB. OBJECTIVE: To determine the prevalence of MDR TB in North Bihar by molecular diagnostic method and to facilitate early diagnosis and treatment. Also, to find out the number of those diagnosed cases who were successfully initiated the treatment in MDR TB Centre of DMCH. MATERIALS AND METHODS: This six month observational study was carried out in IRL Darbhanga, Damien TB research Centre of the Darbhanga Medical College and Hospital, Bihar, India. During the period of February-July 2014, 256 sputum samples were collected from suspected cases of multidrug resistant tuberculosis, from 6 districts of North Bihar around Darbhanga. These samples were subjected to routine microscopy and culture to detect Mycobacterium tuberculosis. Positive cases were subjected to drug sensitivity test by a molecular diagnostic method, Using Genotype MTBDR plus kit. RESULT: Out of 256 sputum samples from suspected cases of MDR TB, 122 cases were microscopy positive for tuberculosis. Among these 122 cases, tuberculosis was confirmed by PCR in 114 cases. Finally with the help of Line Probe Assay (LPA), 39(15%) samples were found to have resistance to both INH and Rifampicin. Male female ratio was 4:1. CONCLUSION: The Prevalence of Multi drug resistant pulmonary tuberculosis in North Bihar is 15%. It needs early diagnosis by molecular diagnostic method and prompt treatment to reduce the spread of MDR TB cases.

20.
Free Radic Biol Med ; 65: 1078-1089, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23999506

RESUMO

The chemotherapeutic isothiocyanate sulforaphane (SFN) was early linked to anticarcinogenic and antiproliferative activities. Soon after, this compound, derived from cruciferous vegetables, became an excellent and useful trial for anti-cancer research in experimental models including growth tumor, metastasis, and angiogenesis. Many subsequent reports showed modifications in mitochondrial signaling, functionality, and integrity induced by SFN. When cytoprotective effects were found in toxic and ischemic insult models, seemingly contradictory behaviors of SFN were discovered: SFN was inducing deleterious changes in cancer cell mitochondria that eventually would carry the cell to death via apoptosis and also was protecting noncancer cell mitochondria against oxidative challenge, which prevented cell death. In both cases, SFN exhibited effects on mitochondrial redox balance and phase II enzyme expression, mitochondrial membrane potential, expression of the family of B cell lymphoma 2 homologs, regulation of proapoptotic proteins released from mitochondria, activation/inactivation of caspases, mitochondrial respiratory complex activities, oxygen consumption and bioenergetics, mitochondrial permeability transition pore opening, and modulation of some kinase pathways. With the ultimate findings related to the induction of mitochondrial biogenesis by SFN, it could be considered that SFN has effects on mitochondrial dynamics that explain some divergent points. In this review, we list the reports involving effects on mitochondrial modulation by SFN in anti-cancer models as well as in cytoprotective models against oxidative damage. We also attempt to integrate the data into a mechanism explaining the various effects of SFN on mitochondrial function in only one concept, taking into account mitochondrial biogenesis and dynamics and making a comparison with the theory of reactive oxygen species threshold of cell death. Our interest is to achieve a complete view of cancer and protective therapies based on SFN that can be extended to other chemotherapeutic compounds with similar characteristics. The work needed to test this hypothesis is quite extensive.


Assuntos
Antioxidantes/farmacologia , Isotiocianatos/farmacologia , Mitocôndrias/fisiologia , Animais , Apoptose , Humanos , Mitocôndrias/efeitos dos fármacos , Renovação Mitocondrial/efeitos dos fármacos , Neoplasias/metabolismo , Estresse Oxidativo , Sulfóxidos
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