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1.
Cell ; 177(5): 1262-1279.e25, 2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31056284

RESUMO

Ferroptosis, a non-apoptotic form of programmed cell death, is triggered by oxidative stress in cancer, heat stress in plants, and hemorrhagic stroke. A homeostatic transcriptional response to ferroptotic stimuli is unknown. We show that neurons respond to ferroptotic stimuli by induction of selenoproteins, including antioxidant glutathione peroxidase 4 (GPX4). Pharmacological selenium (Se) augments GPX4 and other genes in this transcriptional program, the selenome, via coordinated activation of the transcription factors TFAP2c and Sp1 to protect neurons. Remarkably, a single dose of Se delivered into the brain drives antioxidant GPX4 expression, protects neurons, and improves behavior in a hemorrhagic stroke model. Altogether, we show that pharmacological Se supplementation effectively inhibits GPX4-dependent ferroptotic death as well as cell death induced by excitotoxicity or ER stress, which are GPX4 independent. Systemic administration of a brain-penetrant selenopeptide activates homeostatic transcription to inhibit cell death and improves function when delivered after hemorrhagic or ischemic stroke.


Assuntos
Isquemia Encefálica , Peptídeos Penetradores de Células/farmacologia , Ferroptose/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hemorragias Intracranianas , Neurônios , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/biossíntese , Selênio/farmacologia , Acidente Vascular Cerebral , Transcrição Gênica/efeitos dos fármacos , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Hemorragias Intracranianas/tratamento farmacológico , Hemorragias Intracranianas/metabolismo , Hemorragias Intracranianas/patologia , Masculino , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Fator de Transcrição Sp1/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia , Fator de Transcrição AP-2/metabolismo
2.
Arch Virol ; 169(7): 137, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38847873

RESUMO

The present study focuses on the pathological and molecular characterization of African swine fever virus (ASFV) associated with an outbreak in wild boars in two national parks in southern India in 2022-2023. Significant mortality was observed among free-ranging wild boars at Bandipur National Park, Karnataka, and Mudumalai National Park, Tamil Nadu. Extensive combing operations were undertaken in both national parks, spanning an area of around 100 km2, originating from the reported epicenter, to estimate the mortality rate. Recovered carcasses were pathologically examined, and ASFV isolates was genetically characterized. Our findings suggested spillover infection of ASFV from nearby domestic pigs, and the virus was equally pathogenic in wild boars and domestic pigs. ASFV intrusion was reported in the Northeastern region of the country, which borders China and Myanmar, whereas the current outbreak is very distantly located, in southern India. Molecular data will help in tracing the spread of the virus in the country.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Surtos de Doenças , Sus scrofa , Animais , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/isolamento & purificação , Índia/epidemiologia , Suínos , Febre Suína Africana/virologia , Febre Suína Africana/epidemiologia , Febre Suína Africana/mortalidade , Sus scrofa/virologia , Surtos de Doenças/veterinária , Filogenia , Animais Selvagens/virologia
3.
BMC Infect Dis ; 24(1): 79, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216882

RESUMO

BACKGROUND: Pneumococcal disease caused by Streptococcus pneumoniae is an important cause of morbidity and mortality across all ages, particularly in younger children and older adults. Here, we describe pneumococcal disease hospitalizations at Ministry of Health (MoH) facilities in Malaysia between 2013 and 2015. METHODS: This was a retrospective databases analysis. Tabular data from the Malaysian Health Data Warehouse (MyHDW) were used to identify microbiologically confirmed, pneumococcal disease hospitalizations and deaths during hospitalization, using hospital-assigned ICD-10 codes (i.e., classified as meningitis, pneumonia, or non-meningitis non-pneumonia). Case counts, mortality counts, and case fatality rates were reported by patient age group and by Malaysian geographic region. RESULTS: A total of 683 pneumococcal disease hospitalizations were identified from the analysis: 53 pneumococcal meningitis hospitalizations (5 deaths and 48 discharges), 413 pneumococcal pneumonia hospitalizations (24 deaths and 389 discharges), and 205 non-meningitis non-pneumonia pneumococcal disease hospitalizations (58 deaths and 147 discharges). Most hospitalizations occurred in children aged < 2 years. Crude mortality was highest among children aged < 2 years (for all three disease categories), among adults aged ≥ 65 years (for pneumococcal pneumonia), or among adults aged 65-85 years (for non-meningitis non-pneumonia pneumococcal disease). The case fatality rate, all ages included, was 5.8% for pneumococcal pneumonia, 9.1% for pneumococcal meningitis, and 28.3% for non-meningitis non-pneumonia pneumococcal disease. CONCLUSIONS: Our study is the first to document pneumococcal disease hospitalizations and deaths during hospitalization in Malaysia. Although this database analysis likely underestimated case counts, and the true disease burden could be even greater, the study demonstrates a substantial burden of pneumococcal disease. Public health measures, including vaccination, would significantly contribute to the prevention of hospitalizations and deaths associated with pneumococcal disease in Malaysia.


Assuntos
Meningite Pneumocócica , Infecções Pneumocócicas , Pneumonia Pneumocócica , Criança , Humanos , Lactente , Idoso , Pneumonia Pneumocócica/epidemiologia , Pneumonia Pneumocócica/prevenção & controle , Estudos Retrospectivos , Infecções Pneumocócicas/prevenção & controle , Streptococcus pneumoniae , Hospitalização , Atenção à Saúde , Vacinas Pneumocócicas
4.
J Neurosci ; 42(10): 2065-2079, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-34987108

RESUMO

Ferroptosis is a caspase-independent, iron-dependent form of regulated necrosis extant in traumatic brain injury, Huntington disease, and hemorrhagic stroke. It can be activated by cystine deprivation leading to glutathione depletion, the insufficiency of the antioxidant glutathione peroxidase-4, and the hemolysis products hemoglobin and hemin. A cardinal feature of ferroptosis is extracellular signal-regulated kinase (ERK)1/2 activation culminating in its translocation to the nucleus. We have previously confirmed that the mitogen-activated protein (MAP) kinase kinase (MEK) inhibitor U0126 inhibits persistent ERK1/2 phosphorylation and ferroptosis. Here, we show that hemin exposure, a model of secondary injury in brain hemorrhage and ferroptosis, activated ERK1/2 in mouse neurons. Accordingly, MEK inhibitor U0126 protected against hemin-induced ferroptosis. Unexpectedly, U0126 prevented hemin-induced ferroptosis independent of its ability to inhibit ERK1/2 signaling. In contrast to classical ferroptosis in neurons or cancer cells, chemically diverse inhibitors of MEK did not block hemin-induced ferroptosis, nor did the forced expression of the ERK-selective MAP kinase phosphatase (MKP)3. We conclude that hemin or hemoglobin-induced ferroptosis, unlike glutathione depletion, is ERK1/2-independent. Together with recent studies, our findings suggest the existence of a novel subtype of neuronal ferroptosis relevant to bleeding in the brain that is 5-lipoxygenase-dependent, ERK-independent, and transcription-independent. Remarkably, our unbiased phosphoproteome analysis revealed dramatic differences in phosphorylation induced by two ferroptosis subtypes. As U0126 also reduced cell death and improved functional recovery after hemorrhagic stroke in male mice, our analysis also provides a template on which to build a search for U0126's effects in a variant of neuronal ferroptosis.SIGNIFICANCE STATEMENT Ferroptosis is an iron-dependent mechanism of regulated necrosis that has been linked to hemorrhagic stroke. Common features of ferroptotic death induced by diverse stimuli are the depletion of the antioxidant glutathione, production of lipoxygenase-dependent reactive lipids, sensitivity to iron chelation, and persistent activation of extracellular signal-regulated kinase (ERK) signaling. Unlike classical ferroptosis induced in neurons or cancer cells, here we show that ferroptosis induced by hemin is ERK-independent. Paradoxically, the canonical MAP kinase kinase (MEK) inhibitor U0126 blocks brain hemorrhage-induced death. Altogether, these data suggest that a variant of ferroptosis is unleashed in hemorrhagic stroke. We present the first, unbiased phosphoproteomic analysis of ferroptosis as a template on which to understand distinct paths to cell death that meet the definition of ferroptosis.


Assuntos
Ferroptose , Acidente Vascular Cerebral Hemorrágico , Animais , Antioxidantes/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glutationa/metabolismo , Hemina/metabolismo , Hemina/farmacologia , Hemoglobinas/metabolismo , Hemorragias Intracranianas/metabolismo , Ferro/metabolismo , Masculino , Camundongos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Necrose/metabolismo , Neurônios/metabolismo , Fosforilação
5.
Glia ; 71(3): 648-666, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36565279

RESUMO

Hypoxic preconditioning is protective in multiple models of injury and disease, but whether it is beneficial for cells transplanted into sites of spinal cord injury (SCI) is largely unexplored. In this study, we analyzed whether hypoxia-related preconditioning protected Schwann cells (SCs) transplanted into the contused thoracic rat spinal cord. Hypoxic preconditioning was induced in SCs prior to transplantation by exposure to either low oxygen (1% O2 ) or pharmacological agents (deferoxamine or adaptaquin). All preconditioning approaches induced hypoxic adaptations, including increased expression of HIF-1α and its target genes. These adaptations, however, were transient and resolved within 24 h of transplantation. Pharmacological preconditioning attenuated spinal cord oxidative stress and enhanced transplant vascularization, but it did not improve either transplanted cell survival or recovery of sensory or motor function. Together, these experiments show that hypoxia-related preconditioning is ineffective at augmenting either cell survival or the functional outcomes of SC-SCI transplants. They also reveal that the benefits of hypoxia-related adaptations induced by preconditioning for cell transplant therapies are not universal.


Assuntos
Traumatismos da Medula Espinal , Ratos , Animais , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/metabolismo , Hipóxia , Células de Schwann/metabolismo , Transplante de Células , Sobrevivência Celular
6.
Arch Virol ; 167(9): 1819-1829, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35716265

RESUMO

Infectious laryngotracheitis (ILT) is an acute respiratory disease in chickens that is a serious threat to poultry-producing countries worldwide. In the present study, we isolated and characterized infectious laryngotracheitis (ILTV) virus isolates by sequencing and restriction fragment length polymorphism analysis of PCR-amplified products (PCR-RFLP). A total of 26 ILTV outbreaks were investigated that occurred between 2019 and 2020 in flocks that had not been vaccinated against ILTV. ILTV was isolated by cultivating tracheal samples in embryonated chicken eggs, which showed multiple opaque pock lesions and thickening of the chorioallantoic membrane after 120 hours of infection. The ILTV isolates were identified and characterized by PCR and sequencing a portion of the ICP4 and TK genes. Phylogenetic analysis based on the ICP4 region showed that the sequences clustered with chicken-embryo-origin vaccine-like strains. Sequence analysis of the ICP4 region differentiated chicken-embryo-origin (CEO), tissue-culture-origin (TCO), and field ILTV strains, with significant differences in nucleotide and amino acid sequences. Furthermore, PCR-RFLP analysis of the TK gene showed that the patterns were identical to those obtained with low-virulence and vaccine strains. In conclusion, sequencing of a portion of the ICP4 region of ILTV allowed differentiation of ILTV field, CEO, and TCO vaccine strains. In this study, CEO-vaccine-like strains were found to be the cause of ILTV outbreaks between 2019 and 2020 in Tamil Nadu in southern India.


Assuntos
Infecções por Herpesviridae , Herpesvirus Galináceo 1 , Doenças das Aves Domésticas , Vacinas Virais , Animais , Galinhas , Surtos de Doenças/veterinária , Feminino , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/veterinária , Herpesvirus Galináceo 1/genética , Índia/epidemiologia , Filogenia , Doenças das Aves Domésticas/epidemiologia , Vacinas Virais/genética
7.
Genomics ; 113(6): 4254-4266, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34757126

RESUMO

Foot-and-mouth disease virus (FMDV) causes a severe infection in ruminant animals. Here we present an in-depth transcriptional analysis of soft-palate tissue from cattle experimentally infected with FMDV. The differentially expressed genes from two Indian cattle (Bos indicus) breeds (Malnad Gidda and Hallikar) and Holstein Friesian (HF) crossbred calves, highlighted the activation of metabolic processes, mitochondrial functions and significant enrichment of innate antiviral immune response pathways in the indigenous calves. The results of RT-qPCR based validation of 12 genes was in alignment with the transcriptome data. The indigenous calves showing lesser virus load, elicited early neutralizing antibodies and IFN-γ immune responses. This study revealed that induction of potent innate antiviral response and cell mediated immunity in indigenous cattle, especially Malnad Gidda, significantly restricted FMDV replication during acute infection. These data highlighting the molecular processes associated with host-pathogen interactions, could aid in the conception of novel strategies to prevent and control FMDV infection in cattle.


Assuntos
Doenças dos Bovinos , Vírus da Febre Aftosa , Febre Aftosa , Animais , Antivirais/metabolismo , Bovinos , Doenças dos Bovinos/genética , Febre Aftosa/genética , Febre Aftosa/prevenção & controle , Vírus da Febre Aftosa/genética , Vírus da Febre Aftosa/metabolismo , Imunidade Celular , Imunidade Inata/genética , Carga Viral
8.
Trop Anim Health Prod ; 54(6): 410, 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36456854

RESUMO

From the dairy herds (n = 16) reared in few localities of South India with the history of reproductive inefficiency and incidental abortion, 176 sera samples from Jersey (n = 108) and Holstein Friesian (n = 68) crossbred cows were collected to detect prevalence of bovine neosporosis antibodies induced by Neospora caninum (N. caninum) through competitive enzyme linked immuno-sorbent assay (cELISA). The overall true prevalence was found as 23.5% whereas 7.7, 19.1, 25.7 and 40.5% was observed in cows of less than 1 year, 1 to 3 years, 3 to 6 years and above 6 years of age, respectively, denoting that increase in prevalence of N. caninum antibody correlated directly with the age. Among the cattle with and without abortion, 41.1 and 20.6% of true prevalence was found, respectively. The breed-wise true prevalence was 24.3 and 22.2% in Jersey and Holstein Friesians crossbred cows, respectively, indicating that crossbred cows of both breeds are equally susceptible to neosporosis. The prevalence of N. caninum antibody might be attributed to coexistence of dogs resulting in contamination of feed with dog faeces. The presence of dogs with the cattle herd predisposed the herd 3.59 times more to acquire neosporosis than the herd without dogs. The annual estimated economic loss in an aborted herd of having 11 animals was 0.23 million INR due to loss of both calf and milk yield.


Assuntos
Leite , Reprodução , Feminino , Gravidez , Bovinos , Animais , Cães , Estudos Soroepidemiológicos , Anticorpos , Índia/epidemiologia
9.
Neurobiol Dis ; 147: 105145, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33127469

RESUMO

A major thrust of our laboratory has been to identify how physiological stress is transduced into transcriptional responses that feed back to overcome the inciting stress or its consequences, thereby fostering survival and repair. To this end, we have adopted the use of an in vitro model of ferroptosis, a caspase-independent, but iron-dependent form of cell death (Dixon et al., 2012; Ratan, 2020). In this review, we highlight three distinct epigenetic targets that have evolved from our studies and which have been validated in vivo studies. In the first section, we discuss our studies of broad, pan-selective histone deacetylase (HDAC) inhibitors in ferroptosis and how these studies led to the validation of HDAC inhibitors as candidate therapeutics in a host of disease models. In the second section, we discuss our studies that revealed a role for transglutaminase as an epigenetic modulator of proferroptotic pathways and how these studies set the stage for recent elucidation of monoamines as post-translation modifiers of histone function. In the final section, we discuss our studies of iron-, 2-oxoglutarate-, and oxygen-dependent dioxygenases and the role of one family of these enzymes, the HIF prolyl hydroxylases, in mediating transcriptional events necessary for ferroptosis in vitro and for dysfunction in a host of neurological conditions. Overall, our studies highlight the importance of epigenetic proteins in mediating prodeath and prosurvival responses to ferroptosis. Pharmacological agents that target these epigenetic proteins are showing robust beneficial effects in diverse rodent models of stroke, Parkinson's disease, Huntington's disease, and Alzheimer's disease.


Assuntos
Epigênese Genética/fisiologia , Ferroptose/fisiologia , Histona Desacetilases/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Neurônios/patologia , Transglutaminases/metabolismo , Animais , Humanos , Neurônios/metabolismo
10.
Neurobiol Dis ; 136: 104725, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31911115

RESUMO

Identifying disease-causing pathways and drugs that target them in Parkinson's disease (PD) has remained challenging. We uncovered a PD-relevant pathway in which the stress-regulated heterodimeric transcription complex CHOP/ATF4 induces the neuron prodeath protein Trib3 that in turn depletes the neuronal survival protein Parkin. Here we sought to determine whether the drug adaptaquin, which inhibits ATF4-dependent transcription, could suppress Trib3 induction and neuronal death in cellular and animal models of PD. Neuronal PC12 cells and ventral midbrain dopaminergic neurons were assessed in vitro for survival, transcription factor levels and Trib3 or Parkin expression after exposure to 6-hydroxydopamine or 1-methyl-4-phenylpyridinium with or without adaptaquin co-treatment. 6-hydroxydopamine injection into the medial forebrain bundle was used to examine the effects of systemic adaptaquin on signaling, substantia nigra dopaminergic neuron survival and striatal projections as well as motor behavior. In both culture and animal models, adaptaquin suppressed elevation of ATF4 and/or CHOP and induction of Trib3 in response to 1-methyl-4-phenylpyridinium and/or 6-hydroxydopamine. In culture, adaptaquin preserved Parkin levels, provided neuroprotection and preserved morphology. In the mouse model, adaptaquin treatment enhanced survival of dopaminergic neurons and substantially protected their striatal projections. It also significantly enhanced retention of nigrostriatal function. These findings define a novel pharmacological approach involving the drug adaptaquin, a selective modulator of hypoxic adaptation, for suppressing Parkin loss and neurodegeneration in toxin models of PD. As adaptaquin possesses an oxyquinoline backbone with known safety in humans, these findings provide a firm rationale for advancing it towards clinical evaluation in PD.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Proteínas de Ciclo Celular/biossíntese , Transtornos Parkinsonianos/metabolismo , Transtornos Parkinsonianos/prevenção & controle , Piridinas/farmacologia , Quinolinas/farmacologia , Fator de Transcrição CHOP/metabolismo , Fator 4 Ativador da Transcrição/antagonistas & inibidores , Animais , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Células Cultivadas , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxidopamina/toxicidade , Células PC12 , Transtornos Parkinsonianos/induzido quimicamente , Piridinas/uso terapêutico , Quinolinas/uso terapêutico , Ratos , Fator de Transcrição CHOP/antagonistas & inibidores
11.
Ann Neurol ; 84(6): 854-872, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30294906

RESUMO

OBJECTIVES: N-acetylcysteine (NAC) is a clinically approved thiol-containing redox modulatory compound currently in trials for many neurological and psychiatric disorders. Although generically labeled as an "antioxidant," poor understanding of its site(s) of action is a barrier to its use in neurological practice. Here, we examined the efficacy and mechanism of action of NAC in rodent models of hemorrhagic stroke. METHODS: Hemin was used to model ferroptosis and hemorrhagic stroke in cultured neurons. Striatal infusion of collagenase was used to model intracerebral hemorrhage (ICH) in mice and rats. Chemical biology, targeted lipidomics, arachidonate 5-lipoxygenase (ALOX5) knockout mice, and viral-gene transfer were used to gain insight into the pharmacological targets and mechanism of action of NAC. RESULTS: NAC prevented hemin-induced ferroptosis by neutralizing toxic lipids generated by arachidonate-dependent ALOX5 activity. NAC efficacy required increases in glutathione and is correlated with suppression of reactive lipids by glutathione-dependent enzymes such as glutathione S-transferase. Accordingly, its protective effects were mimicked by chemical or molecular lipid peroxidation inhibitors. NAC delivered postinjury reduced neuronal death and improved functional recovery at least 7 days following ICH in mice and can synergize with clinically approved prostaglandin E2 (PGE2 ). INTERPRETATION: NAC is a promising, protective therapy for ICH, which acted to inhibit toxic arachidonic acid products of nuclear ALOX5 that synergized with exogenously delivered protective PGE2 in vitro and in vivo. The findings provide novel insight into a target for NAC, beyond the generic characterization as an antioxidant, resulting in neuroprotection and offer a feasible combinatorial strategy to optimize efficacy and safety in dosing of NAC for treatment of neurological disorders involving ferroptosis such as ICH. Ann Neurol 2018;84:854-872.


Assuntos
Acetilcisteína/uso terapêutico , Araquidonato 5-Lipoxigenase/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Dinoprostona/metabolismo , Sequestradores de Radicais Livres/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Acetilcisteína/farmacologia , Animais , Araquidonato 5-Lipoxigenase/genética , Proteínas de Transporte de Cátions/genética , Núcleo Celular/metabolismo , Núcleo Celular/patologia , Células Cultivadas , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/complicações , Colagenases/toxicidade , Citoplasma/metabolismo , Modelos Animais de Doenças , Eicosanoides/metabolismo , Feminino , Sequestradores de Radicais Livres/farmacologia , Glutationa/metabolismo , Hemina/toxicidade , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
12.
J Med Syst ; 43(4): 84, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30810822

RESUMO

The brain tumor can be created by uncontrollable increase of abnormal cells in tissue of brain and it has two kinds of tumors: one is benign and another one is malignant tumor. The benign brain tumor does not affect the adjacent normal and healthy tissue but the malignant tumor can affect the neighboring tissues of brain that can lead to the death of person. An early detection of brain tumor can be required to protect the survival of patients. Usually, the brain tumor is detected using MRI scanning method. However, the radiologists are not providing the effective tumor segmentation in MRI image due to the irregular shape of tumors and position of tumor in the brain. Accurate brain tumor segmentation is needed to locate the tumor and it is used to give the correct treatment for a patient and it provides the key to the doctor who must execute the surgery for patient. In this paper, a novel deep learning algorithm (kernel based CNN) with M-SVM is presented to segment the tumor automatically and efficiently. This presented work contains several steps that are preprocessing, feature extraction, image classification and tumor segmentation of brain. The MRI image is smoothed and enhanced by Laplacian of Gaussian filtering method (LoG) with Contrast Limited Adaptive Histrogram Equalization (CLAHE) and feature can be extracted from it based on tumor shape position, shape and surface features in brain. Consequently, the image classification is done using M-SVM depending on the selected features. From MRI image, the tumor is segmented with help of kernel based CNN method.. Experimental results of proposed method can show that this presented technique can executes brain tumor segmentation accurately reaching almost 84% in evaluation with existing algorithms.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Aprendizado Profundo , Detecção Precoce de Câncer , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Neoplasias Encefálicas/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Máquina de Vetores de Suporte , Fatores de Tempo
13.
J Viral Hepat ; 25(6): 718-723, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29316078

RESUMO

The study aimed to determine the prevalence of occult hepatitis B virus infection among HIV-infected persons and to evaluate the use of a pooling strategy to detect occult HBV infection in the setting of HIV infection. Five hundred and two HIV-positive individuals were tested for HBV, occult HBV and hepatitis C and D with serologic and nucleic acid testing (NAT). We also evaluated a pooled NAT strategy for screening occult HBV infection among the HIV-positive individuals. The prevalence of HBV infection among HIV-positive individuals was 32 (6.4%), and occult HBV prevalence was 10%. The pooling HBV NAT had a sensitivity of 66.7% and specificity of 100%, compared to HBV DNA NAT of individual samples. In conclusion, this study found a high prevalence of occult HBV infection among our HIV-infected population. We also demonstrated that pooled HBV NAT is highly specific, moderately sensitive and cost-effective. As conventional HBV viral load assays are expensive in resource-limited settings such as India, pooled HBV DNA NAT might be a good way for detecting occult HBV infection and will reduce HBV-associated complications.


Assuntos
DNA Viral/isolamento & purificação , Infecções por HIV/complicações , Vírus da Hepatite B/isolamento & purificação , Hepatite B/diagnóstico , Hepatite B/epidemiologia , Técnicas de Diagnóstico Molecular/métodos , Manejo de Espécimes/métodos , Adulto , Feminino , Hepatite C/diagnóstico , Hepatite C/epidemiologia , Hepatite D/diagnóstico , Hepatite D/epidemiologia , Humanos , Índia/epidemiologia , Masculino , Sensibilidade e Especificidade
14.
Stroke ; 48(4): 1033-1043, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28250197

RESUMO

BACKGROUND AND PURPOSE: Intracerebral hemorrhage leads to disability or death with few established treatments. Adverse outcomes after intracerebral hemorrhage result from irreversible damage to neurons resulting from primary and secondary injury. Secondary injury has been attributed to hemoglobin and its oxidized product hemin from lysed red blood cells. The aim of this study was to identify the underlying cell death mechanisms attributable to secondary injury by hemoglobin and hemin to broaden treatment options. METHODS: We investigated cell death mechanisms in cultured neurons exposed to hemoglobin or hemin. Chemical inhibitors implicated in all known cell death pathways were used. Identified cell death mechanisms were confirmed using molecular markers and electron microscopy. RESULTS: Chemical inhibitors of ferroptosis and necroptosis protected against hemoglobin- and hemin-induced toxicity. By contrast, inhibitors of caspase-dependent apoptosis, protein or mRNA synthesis, autophagy, mitophagy, or parthanatos had no effect. Accordingly, molecular markers of ferroptosis and necroptosis were increased after intracerebral hemorrhage in vitro and in vivo. Electron microscopy showed that hemin induced a necrotic phenotype. Necroptosis and ferroptosis inhibitors each abrogated death by >80% and had similar therapeutic windows in vitro. CONCLUSIONS: Experimental intracerebral hemorrhage shares features of ferroptotic and necroptotic cell death, but not caspase-dependent apoptosis or autophagy. We propose that ferroptosis or necroptotic signaling induced by lysed blood is sufficient to reach a threshold of death that leads to neuronal necrosis and that inhibition of either of these pathways can bring cells below that threshold to survival.


Assuntos
Apoptose , Hemorragia Cerebral/metabolismo , Hemina/metabolismo , Hemoglobinas/metabolismo , Necrose/metabolismo , Neurônios/metabolismo , Animais , Células Cultivadas , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
J Neurosci ; 34(43): 14328-37, 2014 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-25339746

RESUMO

Histone deacetylase (HDAC) inhibition improves function and extends survival in rodent models of a host of neurological conditions, including stroke, and neurodegenerative diseases. Our understanding, however, of the contribution of individual HDAC isoforms to neuronal death is limited. In this study, we used selective chemical probes to assess the individual roles of the Class I HDAC isoforms in protecting Mus musculus primary cortical neurons from oxidative death. We demonstrated that the selective HDAC8 inhibitor PCI-34051 is a potent neuroprotective agent; and by taking advantage of both pharmacological and genetic tools, we established that HDAC8 is not critically involved in PCI-34051's mechanism of action. We used BRD3811, an inactive ortholog of PCI-34051, and showed that, despite its inability to inhibit HDAC8, it exhibits robust neuroprotective properties. Furthermore, molecular deletion of HDAC8 proved insufficient to protect neurons from oxidative death, whereas both PCI-34051 and BRD3811 were able to protect neurons derived from HDAC8 knock-out mice. Finally, we designed and synthesized two new, orthogonal negative control compounds, BRD9715 and BRD8461, which lack the hydroxamic acid motif and showed that they stably penetrate cell membranes but are not neuroprotective. These results indicate that the protective effects of these hydroxamic acid-containing small molecules are likely unrelated to direct epigenetic regulation via HDAC inhibition, but rather due to their ability to bind metals. Our results suggest that hydroxamic acid-based HDAC inhibitors may mediate neuroprotection via HDAC-independent mechanisms and affirm the need for careful structure-activity relationship studies when using pharmacological approaches.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Células Cultivadas , Córtex Cerebral/patologia , Feminino , Camundongos , Camundongos Transgênicos , Neurônios/patologia , Gravidez
16.
J Nanobiotechnology ; 13: 40, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26065678

RESUMO

BACKGROUND: Bone loss during trauma, surgeries, and tumor resection often results in critical-sized bone defects that need to be filled with substitutionary materials. Complications associated with conventional grafting techniques have led to the development of bioactive tissue-engineered bone scaffolds. The potential application of hydrogels as three-dimensional (3D) matrices in tissue engineering has gained attention in recent years because of the superior sensitivity, injectability, and minimal invasive properties of hydrogels. Improvements in the bioactivity and mechanical strength of hydrogels can be achieved with the addition of ceramics. Based on the features required for bone regeneration, an injectable thermosensitive hydrogel containing zinc-doped chitosan/nanohydroxyapatite/beta-glycerophosphate (Zn-CS/nHAp/ß-GP) was prepared and characterized, and the effect of nHAp on the hydrogel was examined. METHODS: Hydrogels (Zn-CS/ß-GP, Zn-CS/nHAp/ß-GP) were prepared using the sol-gel method. Characterization was carried out by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) as well as swelling, protein adsorption, and exogenous biomineralization studies. Expression of osteoblast marker genes was determined by real-time reverse transcriptase polymerase chain reaction (RT-PCR) and western blot analyses. In vivo bone formation was studied using a rat bone defect model system. RESULTS: The hydrogels exhibited sol-gel transition at 37°C. The presence of nHAp in the Zn-CS/nHAp/ß-GP hydrogel enhanced swelling, protein adsorption, and exogenous biomineralization. The hydrogel was found to be non-toxic to mesenchymal stem cells. The addition of nHAp to the hydrogel also enhanced osteoblast differentiation under osteogenic conditions in vitro and accelerated bone formation in vivo as seen from the depositions of apatite and collagen. CONCLUSIONS: The synthesized injectable hydrogel (Zn-CS/nHAp/ß-GP) showed its potential toward bone formation at molecular and cellular levels in vitro and in vivo. The current findings demonstrate the importance of adding nHAp to the hydrogel, thereby accelerating potential clinical application toward bone regeneration.


Assuntos
Quitosana/química , Durapatita/química , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Nanocompostos , Osteogênese/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Glicerofosfatos/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Masculino , Teste de Materiais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Microscopia Eletrônica de Varredura , Nanocompostos/química , Osteoblastos/efeitos dos fármacos , Osteogênese/fisiologia , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Tíbia/efeitos dos fármacos , Difração de Raios X , Zinco/química
17.
Pharm Biol ; 53(2): 174-84, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25289526

RESUMO

CONTEXT: Delonix elata (L.) Gamble (Fabaceae) has been used in the Indian traditional medicine system to treat rheumatism and inflammation. AIM: To assess the anti-inflammatory effect of Delonix elata flowers and to isolate the active principle. MATERIALS AND METHODS: The prompt anti-inflammatory constituent was isolated from Delonix elata flower extracts using bioassay guided fractionation in liposaccharide (LPS) stimulated RAW 264.7 macrophage cell line. The anti-inflammatory activity of extracts/fractions/sub-fractions/compounds (10, 25, and 50 µg/ml) was evaluated by estimating the levels of nitric oxide (NO), TNF-α, and IL-1ß after 24 h of LPS induction (1 µg/ml). The isolated active compound was subjected to NMR, IR, and UV analyses for structure determination. RESULTS: In an attempt to search for anti-inflammatory constituents, the active pure principle was isolated and crystallized as a white compound from Delonix elata flowers methanol extract. This active compound (50 µg/ml) decreased the release of inflammatory mediators levels such as NO (0.263 ± 0.03 µM), TNFα (160.20 ± 17.57 pg/ml), and IL-1ß (285.79 ± 15.16 pg/ml) significantly (p < 0.05); when compared to the levels of NO (0.774 ± 0.08 µM), TNFα (501.71 ± 25.14 pg/ml), and IL-1ß (712.68 ± 52.25 pg/ml) from LPS-stimulated macrophage cells. The active compound was confirmed as hesperidin with NMR, IR, and UV spectroscopy data. This is the first report of this compound from Delonix elata flowers. CONCLUSION: The findings of the study support the traditional use of Delonix elata flowers to treat inflammation.


Assuntos
Anti-Inflamatórios não Esteroides/isolamento & purificação , Fabaceae/química , Hesperidina/isolamento & purificação , Macrófagos/efeitos dos fármacos , Extratos Vegetais/química , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/toxicidade , Bioensaio , Linhagem Celular , Fracionamento Químico , Relação Dose-Resposta a Droga , Flores/química , Hesperidina/farmacologia , Hesperidina/toxicidade , Interleucina-1beta/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
Inflamm Res ; 63(2): 127-38, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24202617

RESUMO

INTRODUCTION: The leaves of Clerodendrum phlomidis L.f. have been used in the Indian traditional system of medicine to treat several inflammatory diseases and arthritis. The aim of the present study was to assess the anti-inflammatory and anti-arthritic activities of the leaves of C. phlomidis and to isolate the active principle by bioactivity guided fractionation. MATERIALS AND METHODS: To find the anti-inflammatory constituents from this plant, fractionations were performed with concurrent bioassays. Carrageenan-induced inflammation and Freund complete adjuvant (FCA)-induced arthritic rat models were used. The anti-inflammatory and anti-arthritic activities of the isolated compound were studied by assessing the histology of the joints, levels of lysosomal enzymes, protein-bound carbohydrates, acute phase protein, etc., in plasma, as well as by estimating the levels and expression of pro-inflammatory cytokines in the joints. RESULTS: Repeated fractionations and bioassays yielded a novel bioactive compound: 3-hydroxy, 2-methoxy-sodium butanoate. Treatment with this compound reduced the paw edema induced by carrageenan and FCA dose dependently. The levels of lysosomal enzymes and protein-bound carbohydrates decreased significantly upon treatment with the compound. The level of plasma acute phase protein was also decreased compared with control animals. Protein levels and mRNA expression of pro-inflammatory cytokines TNF, IL-1 and IL-6 in the joints were decreased significantly in a dose-dependent manner and the histopathological data also added evidence of the anti-arthritic property of the compound. CONCLUSION: The 3-hydroxy,2-methoxy sodium butanoate isolated from plant leaves displays considerable potency in anti-inflammatory action and has a prominent anti-arthritic effect. This is the first report of this natural compound with bioactivity.


Assuntos
Artrite Experimental/tratamento farmacológico , Butiratos/uso terapêutico , Clerodendrum , Edema/tratamento farmacológico , Fitoterapia , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Artrite Experimental/imunologia , Artrite Experimental/patologia , Butiratos/farmacologia , Carragenina , Citocinas/genética , Citocinas/imunologia , Edema/induzido quimicamente , Edema/imunologia , Edema/patologia , Feminino , Articulações do Pé/imunologia , Articulações do Pé/patologia , Índia , Medicina Tradicional do Leste Asiático , Neutrófilos/imunologia , Peroxidase/imunologia , Extratos Vegetais/química , Folhas de Planta/química , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/imunologia
19.
Inflamm Res ; 63(6): 451-62, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24492951

RESUMO

OBJECTIVE AND DESIGN: Rheumatoid arthritis is a chronic inflammatory and autoimmune disease that leads to aggressive joint cartilage and bone destruction. Swertiamarin is a secoiridoid glycoside found in Enicostema axillare (Lam) A. Raynal, a medicinal plant used in the Indian system of traditional medicine. In the present study, the potential of swertiamarin was evaluated in IL-1ß induced fibroblast-like synoviocytes (FLS). METHODS: The FLS were isolated from Freund's Complete Adjuvant induced arthritic (AA) rats and cultured with IL-1ß. The normal FLS and AA-FLS were cultured and used for subsequent experiment in fibroblastic morphology form. The efficacy of swertiamarin (10-50 µg/ml) was evaluated on mRNA and protein expression levels of inflammatory and osteoclastogenesis mediators. The efficacy was also evaluated on p38 MAPKα levels with time course studies (2, 4, 6, 8 and 12 h). RESULTS: IL-1ß induced cell proliferation (149.46 ± 13.73 %) and NO production (162.03 ± 11.03%) in AA-FLS; treatment with swertiamarin controlled proliferation (82.77 ± 4.22%) and NO production (82.06 ± 3.91% at 50 µg/ml) in a dose-dependent manner. It also significantly (P < 0.05) modulated the expression of apoptotic marker (caspase 3), proinflammation mediators (TNFα, IL-6, PGE2, COX-2, iNOS, MMPs) and osteoclastogenic mediator (RANKL) at both the mRNA and protein levels. Treatment with swertiamarin inhibited the levels of p38 MAPKα in a dose-dependent manner and also significantly (P < 0.05) attenuated the release of the same in time dependent mode. CONCLUSION: These findings suggest that treatment with swertiamarin attenuated IL-1ß induced FLS, and it revealed anti-inflammatory potential by attenuating aggressive FLS.


Assuntos
Anti-Inflamatórios/farmacologia , Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Glucosídeos Iridoides/farmacologia , Pironas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/imunologia , Camundongos Endogâmicos C57BL , Óxido Nítrico/imunologia , Osteoclastos/citologia , Ligante RANK/imunologia , Ratos Sprague-Dawley , Membrana Sinovial/citologia , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia
20.
Dig Dis Sci ; 59(6): 1121-33, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24395383

RESUMO

BACKGROUND AND AIM: Probiotics are live microorganisms that confer a health benefit on the host when administered in adequate amounts. In the present study, the putative probiotic strain was identified from the gut of Drosophila melanogaster and assessed for its protective effect in inflammatory bowel disease. METHODS: Active probiotics were screened from the Drosophila melanogaster gut by the selection criteria of gastric juice tolerance, hydrophobic property, antimicrobial potential, adhesion, and invasion properties. The active probiotics were identified by 16s rDNA sequencing and the effect of these active probiotics was evaluated in a Dextran sulphate sodium (DSS)-induced mice model by estimating inflammatory markers and histopathological changes. RESULTS: Nine Gram-positive and bile salt tolerant bacterial isolates were obtained from the gut samples. The isolates PTH 2, PTH 4, and PTH 7 clearly showed significant activity in antimicrobial potential, hydrophobic (>74%) property, and intestinal juice tolerance. Among these, PTH 7 was selected for further studies due to its significant low-invasion ability and it proved capable of reducing the secretion of proinflammatory cytokines. The 16s rDNA studies revealed that PTH 7 was Myroides pelagicus. Administration of M. pelagicus to the DSS-induced colitic animals significantly suppressed myeloperoxidase, ALP, and malondialdehyde levels, and also lowered levels of proinflammatory cytokine expression. Further, the recovery from the disease by the probiotic treatment was supported by histopathological and macroscopic observation. The treated animals did not show any adverse signs in their physiology or behavior. CONCLUSION: Myroides pelagicus successfully prohibited inflammatory markers and acted as a potent probiotic. Future studies with this stain might prove its efficacy as a drug for the management of colitis.


Assuntos
Colite/terapia , Sulfato de Dextrana/toxicidade , Drosophila melanogaster/microbiologia , Flavobacteriaceae/fisiologia , Trato Gastrointestinal/microbiologia , Probióticos/uso terapêutico , Animais , Peso Corporal , Células CACO-2 , Colite/induzido quimicamente , Colite/patologia , Colo/patologia , Flavobacteriaceae/classificação , Flavobacteriaceae/isolamento & purificação , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Probióticos/isolamento & purificação
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