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1.
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
2.
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
3.
Neuron ; 111(18): 2831-2846.e10, 2023 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-37453419

RESUMO

Intermittent fasting (IF) is a diet with salutary effects on cognitive aging, Alzheimer's disease (AD), and stroke. IF restricts a number of nutrient components, including glucose. 2-deoxyglucose (2-DG), a glucose analog, can be used to mimic glucose restriction. 2-DG induced transcription of the pro-plasticity factor, Bdnf, in the brain without ketosis. Accordingly, 2-DG enhanced memory in an AD model (5xFAD) and functional recovery in an ischemic stroke model. 2-DG increased Bdnf transcription via reduced N-linked glycosylation, consequent ER stress, and activity of ATF4 at an enhancer of the Bdnf gene, as well as other regulatory regions of plasticity/regeneration (e.g., Creb5, Cdc42bpa, Ppp3cc, and Atf3) genes. These findings demonstrate an unrecognized role for N-linked glycosylation as an adaptive sensor to reduced glucose availability. They further demonstrate that ER stress induced by 2-DG can, in the absence of ketosis, lead to the transcription of genes involved in plasticity and cognitive resilience as well as proteostasis.


Assuntos
Doença de Alzheimer , Cetose , Acidente Vascular Cerebral , Humanos , Desoxiglucose/farmacologia , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Glucose/metabolismo , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo
4.
J Mech Behav Biomed Mater ; 142: 105851, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37068434

RESUMO

Titanium alloys have gained popularity as a bioimplant material due to their biocompatibility, low modulus of elasticity, and increased strength. However, other issues, such as corrosion resistance, and infections can reduce the implant's lifespan. This paper aims to fabricate a new Ti-30Nb-3Ag at% alloy with enhanced in vitro corrosion and antibacterial properties by mechanical alloying (MA) followed by powder consolidation. XRD, SEM/EDX, and Vickers microhardness analyses were used to examine the phases compositions, microstructure, and microhardness, respectively. The in vitro corrosion performance of Ti-30Nb-3Ag alloy was inspected in a simulated body medium and artificial saliva. The alloy's antibacterial properties were evaluated in the gram-positive and negative bacterial medium. The results showed that after MA for 60 h, nanocrystalline ß-Ti (BCC) and α-Ti (HCP) solid solutions were formed with crystallite sizes of 7.44 and 3.47 nm, respectively. The sintered sample exhibited densifications of 97%, with a microstructure composed of ß-Ti, α-Ti, and a minor quantity of ultrafine Ti2Ag phase. The microhardness result showed that Ti-30Nb-3Ag alloy possesses HV 491.5. Ti-30Nb-3Ag alloy has a potent antibacterial capability of 85.75% and 88.81% relative to Ti-6Al-4V alloy and CP-Ti, respectively. In vitro corrosion results revealed that the Ti-30Nb-3Ag alloy exhibited the widespread passive area in the investigated anodic regions and presented the highest impedance values in comparison with the commercial alloys, confirming its improved corrosion resistance performance in both studied mediums. Ti-30Nb-3Ag alloy possibly be a competitive bioimplant material for orthopedic and dental uses owing to its enhanced biocorrosion and antibacterial properties compared to commercial Ti-6Al-4V alloy and CP-Ti.


Assuntos
Ligas , Titânio , Titânio/farmacologia , Titânio/química , Corrosão , Ligas/farmacologia , Ligas/química , Antibacterianos/farmacologia , Antibacterianos/química , Propriedades de Superfície , Teste de Materiais
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.
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
7.
Comput Math Methods Med ; 2022: 4380901, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36277002

RESUMO

The classification of the brain tumor image is playing a vital role in the medical image domain, and it directly assists the clinicians to understand the severity and to take an appropriate solution. The magnetic resonance imaging tool is used to analyze the brain tissues and to examine the different portion of brain circumstance. We propose the convolutional neural network database learning along with neighboring network limitation (CDBLNL) technique for brain tumor image classification in medical image processing domain. The proposed system architecture is constructed with multilayer-based metadata learning, and they have integrated with CNN layer to deliver the accurate information. The metadata-based vector encoding is used, and the type of coding estimation for extra dimension is known as sparse. In order to maintain the supervised data in terms of geometric format, the atoms of neighboring limitation are built based on a well-structured k-neighbored network. The resultant of the proposed system is considerably strong and subjective for classification. The proposed system used two different datasets, such as BRATS and REMBRANDT, and the proposed brain MRI classification technique outcome is more efficient than the other existing techniques.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Glioma/diagnóstico por imagem , Glioma/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia
8.
Bioinorg Chem Appl ; 2022: 4513208, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35903518

RESUMO

Several industries have become major contributors to waterbody contamination due to the improper removal of dyes and effluents into water bodies. Due to their carcinogenic properties and low biodegradability, dye degradation is a considerable danger to people, animals, and the oceanic environment. As part of this study, Andrographis paniculata leaf extract was used as a reducing and stabilizing agent to synthesize zinc nanoparticles and degrade dyes such as methyl red and eosin. Zinc oxide nanoparticles (ZnONPs) showed a surface plasmon resonance peak at 430 nm in the UV spectrum. The FTIR result showed a band at 597.93 cm-1 that confirmed the formation of zinc nanoparticles. AFM results revealed spherical ZnONPs. The SEM results predicted an average particle size of 60 nm for crystalline particles. Biologically synthesized zinc nanoparticles exhibited greater antibacterial activity against Pseudomonas spp. and Proteus spp. but lesser activity against Klebsiella spp. and S. aureus. At 1000 µg/ml concentration, ZnONPs had the highest antioxidant activity of 45.34%. An ultraviolet-visible spectrophotometer measured dye degradation progress between 300 and 800 nm. For methyl red, the maximum absorption peak was measured at 415 nm, and for eosin, the maximum peak value was measured between 500 and 515 nm.

10.
Brain Commun ; 4(3): fcac133, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35694149

RESUMO

Converging lines of inquiry have highlighted the importance of the Type I antiviral response not only in defending against viruses but also in preconditioning the brain against ischaemic stroke. Despite this understanding, treatments that foster brain resilience by driving antiviral interferon responses have yet to be developed for human use. Studies from our laboratory showed that tilorone, the first human antiviral immunomodulatory agent to be developed, robustly preconditioned against stroke in mice and rats. Tilorone is a DNA intercalator; therefore, we hypothesized that it stabilizes cytosolic DNA (released from the mitochondria or the nucleus), thereby activating cyclic GMP-AMP synthase, a homeostatic DNA sensor, and its downstream pathway. This pathway involves st imulator of in terferon g enes (STING), tank-binding kinase 1 (TBK1), and i nterferon r egulatory p rotein-3 and culminates in a protective Type I interferon response. We tested this hypothesis by examining the ability of structurally diverse small-molecule agonists of STING to protect against oxygen/glucose deprivation in vitro in mouse cortical cultures and in vivo against transient ischaemia in mice. The STING agonists significantly reduced cell death both in vitro and in vivo but failed to do so in STING knockout mice. As expected, STING agonist-induced protection was associated with the induction of interferon related genes and the effects could be abrogated in vitro by a TBK1 inhibitor. Taken together, these findings in mice identify STING as a therapeutic target for preconditioning the brain against ischaemic stroke in vitro and in vivo. Moreover, they suggest that clinically approved STING agonists such as Ganciclovir or α-Mangostin are candidate drugs that could be tested in humans as a prophylactic treatment to alleviate brain injury associated with ischaemic stroke.

11.
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
12.
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
13.
Chemosphere ; 286(Pt 2): 131823, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34426138

RESUMO

Natural sunlight-driven photocatalytic hydrogen production from wastewater is one of the most desirable techniques that can realize future green energy technology. Herein, we report the synthesis and the characterization of the biomass activated carbon (AC)-decorated cobalt oxide (Co3O4) nanocomposites for solar-stimulated photocatalytic hydrogen production from sulphide wastewater. The Co3O4-AC nanocomposites were ultrasonically synthesized by using hydrothermally-grown spinel Co3O4 nanoflakes and biomass-derived AC nanoflakes. Co3O4-AC showed a nanobundle-like aggregated morphology, and exhibited a large specific surface area (~133 m2/g). Through utilizing Co3O4-AC as a photocatalyst for photocatalytic splitting of sulphide wastewater (0.2 M) under solar irradiance with 730 W/m2, an enhanced H2 production efficiency (~70 mL/h) was achieved owing to the synergic effects from 2-dimentionally configured Co3O4 and AC microstructures; i.e., large surface area of Co3O4 and high electrical conductivity of AC. These findings suggest the nanocomposites of Co3O4-AC to hold great promise for the green approach of photocatalytic wastewater splitting.


Assuntos
Nanocompostos , Águas Residuárias , Catálise , Carvão Vegetal , Luz Solar
14.
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
15.
Elife ; 102021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34596045

RESUMO

Hypoxic adaptation mediated by HIF transcription factors requires mitochondria, which have been implicated in regulating HIF1α stability in hypoxia by distinct models that involve consuming oxygen or alternatively converting oxygen into the second messenger peroxide. Here, we use a ratiometric, peroxide reporter, HyPer to evaluate the role of peroxide in regulating HIF1α stability. We show that antioxidant enzymes are neither homeostatically induced nor are peroxide levels increased in hypoxia. Additionally, forced expression of diverse antioxidant enzymes, all of which diminish peroxide, had disparate effects on HIF1α protein stability. Moreover, decrease in lipid peroxides by glutathione peroxidase-4 or superoxide by mitochondrial SOD, failed to influence HIF1α protein stability. These data show that mitochondrial, cytosolic or lipid ROS were not necessary for HIF1α stability, and favor a model where mitochondria contribute to hypoxic adaptation as oxygen consumers.


Assuntos
Hipóxia Celular , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Peróxidos/metabolismo , Animais , Células HeLa , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Mitocôndrias/metabolismo , Estabilidade Proteica , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
16.
J Mol Graph Model ; 107: 107971, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34217025

RESUMO

We ascertained the structural stability of zipper phosphorene nanosheet (zP-NS) and studied the adsorption behaviour of toxic aldehyde compounds including formaldehyde (FD) and acetaldehyde (AD) on zP-NS based on first-principles calculation. Considerably, zP-NS reveal a semiconducting character with band gap of 1.35 eV. Especially, four distinct favourable adsorption positions including bridge-, hollow-, top- and valley-site of FD and AD vapours on zP-NS were investigated. Furthermore, the calculated binding-energy of prominent adsorption sites are observed to be in the scope of -0.143 eV to -0.411 eV advocating physisorption nature of the interaction of chief aldehydes on zP-NS. The overall outcomes recommend that zP-NS can be persuasively utilised as a chemical sensor for monitoring FD and AD molecules in indoor air environment.


Assuntos
Acetaldeído , Formaldeído , Adsorção , Aldeídos , Gases
17.
Dalton Trans ; 50(23): 8232-8242, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34037018

RESUMO

Organometallic Ru-arene complexes are promising as anticancer agents, but the lack of tumor uptake and poor solubility in the physiological medium impede their development. In order to deal with these challenges, we developed gold nanoparticles coated with Ru(arene)-functionalized PNVP-Py, where PNVP-Py is pyridine end-functionalized poly(N-vinylpyrrolidone). It is demonstrated that these particles exhibit higher anti-proliferative activity than the individual organometallic ruthenium(ii) complex of the type [Ru(η6-p-cymene)(NN)Cl]PF6, where NN is bis(4-methoxyphenylimino)acenaphthene, against colorectal adenocarcinoma cell lines. More specifically, a RuII(η6-p-cymene) complex containing a NN bidentate ligand has been prepared and characterized by spectral studies and X-ray crystallography. To tether the isolated complex onto the surface of the AuNPs, PNVP-Py, which contains a pyridine group at one end to coordinate to the Ru-complex and a suitable functional group at the other end to bind on the surface of the AuNPs, has been prepared and utilized to obtain the macromolecular complex [Ru(η6-p-cymene)(NN)(PNVP-Py)]Cl2. Next, stable Ru(p-cym)(NN)(PNVP-Py)@AuNPs were obtained via a ligand exchange reaction of citrate-stabilized AuNPs with a macromolecular complex by a direct 'grafting to' approach and characterized well. Despite the lower DNA cleavage activity, the nanoconjugate exhibits better cytotoxicity than the individual complex against HT-29 colorectal adenocarcinoma cells on account of its enhanced permeability across the cell membrane. The AO/EB staining assay revealed that the nanoconjugate is able to induce an apoptotic mode of cell death, which was further quantitatively evaluated by Annexin V-FITC/PI double assay. An immunofluorescence assay indicated the higher potency of the nanoconjugate to inhibit cyclin D1 gene expression that is required for cancer cell growth. To the best of our knowledge, this is the first report of the modification of an organometallic Ru(arene) complex into a Ru(arene)metallopolymer-gold nanoconjugate for the development of ruthenium-based nanomedicine for cancer treatment.


Assuntos
Antineoplásicos/farmacologia , Cimenos/farmacologia , Compostos Organometálicos/farmacologia , Pirrolidinonas/farmacologia , Rutênio/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Cimenos/química , Ensaios de Seleção de Medicamentos Antitumorais , Ouro/química , Humanos , Nanopartículas Metálicas/química , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Tamanho da Partícula , Pirrolidinonas/química , Rutênio/química
18.
Stem Cells Int ; 2021: 8818356, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33828592

RESUMO

Mouse embryonic stem cells (mESCs) and mouse epiblast stem cells (mEpiSCs) are the pluripotent stem cells (PSCs), derived from the inner cell mass (ICM) of preimplantation embryos at embryonic day 3.5 (E3.5) and postimplantation embryos at E5.5-E7.5, respectively. Depending on their environment, PSCs can exist in the so-called naïve (ESCs) or primed (EpiSCs) states. Exposure to EpiSC or human ESC (hESC) culture condition can convert mESCs towards an EpiSC-like state. Here, we show that the undifferentiated epiblast state is however not stabilized in a sustained manner when exposing mESCs to hESC or EpiSC culture condition. Rather, prolonged exposure to EpiSC condition promotes a transition to a primitive streak- (PS-) like state via an unbiased epiblast-like intermediate. We show that the Brachyury-positive PS-like state is likely promoted by endogenous WNT signaling, highlighting a possible species difference between mouse epiblast-like stem cells and human Embryonic Stem Cells.

19.
Sci Immunol ; 6(56)2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33891558

RESUMO

Opportunities to interrogate the immune responses in the injured tissue of living patients suffering from acute sterile injuries such as stroke and heart attack are limited. We leveraged a clinical trial of minimally invasive neurosurgery for patients with intracerebral hemorrhage (ICH), a severely disabling subtype of stroke, to investigate the dynamics of inflammation at the site of brain injury over time. Longitudinal transcriptional profiling of CD14+ monocytes/macrophages and neutrophils from hematomas of patients with ICH revealed that the myeloid response to ICH within the hematoma is distinct from that in the blood and occurs in stages conserved across the patient cohort. Initially, hematoma myeloid cells expressed a robust anabolic proinflammatory profile characterized by activation of hypoxia-inducible factors (HIFs) and expression of genes encoding immune factors and glycolysis. Subsequently, inflammatory gene expression decreased over time, whereas anti-inflammatory circuits were maintained and phagocytic and antioxidative pathways up-regulated. During this transition to immune resolution, glycolysis gene expression and levels of the potent proresolution lipid mediator prostaglandin E2 remained elevated in the hematoma, and unexpectedly, these elevations correlated with positive patient outcomes. Ex vivo activation of human macrophages by ICH-associated stimuli highlighted an important role for HIFs in production of both inflammatory and anti-inflammatory factors, including PGE2, which, in turn, augmented VEGF production. Our findings define the time course of myeloid activation in the human brain after ICH, revealing a conserved progression of immune responses from proinflammatory to proresolution states in humans after brain injury and identifying transcriptional programs associated with neurological recovery.


Assuntos
Encéfalo/patologia , Hemorragia Cerebral/complicações , Doenças Neuroinflamatórias/imunologia , Adulto , Idoso , Encéfalo/imunologia , Células Cultivadas , Hemorragia Cerebral/imunologia , Hemorragia Cerebral/patologia , Feminino , Voluntários Saudáveis , Hematoma , Humanos , Estudos Longitudinais , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Doenças Neuroinflamatórias/patologia , Neutrófilos/imunologia , Cultura Primária de Células , RNA-Seq , Transcriptoma/imunologia
20.
PLoS One ; 16(4): e0249591, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33819286

RESUMO

Traumatic spinal cord injury (SCI) is a devastating neurological condition that involves both primary and secondary tissue loss. Various cytotoxic events including hypoxia, hemorrhage and blood lysis, bioenergetic failure, oxidative stress, endoplasmic reticulum (ER) stress, and neuroinflammation contribute to secondary injury. The HIF prolyl hydroxylase domain (PHD/EGLN) family of proteins are iron-dependent, oxygen-sensing enzymes that regulate the stability of hypoxia inducible factor-1α (HIF-1α) and also mediate oxidative stress caused by free iron liberated from the lysis of blood. PHD inhibition improves outcome after experimental intracerebral hemorrhage (ICH) by reducing activating transcription factor 4 (ATF4)-driven neuronal death. As the ATF4-CHOP (CCAAT-enhancer-binding protein homologous protein) pathway plays a role in the pathogenesis of contusive SCI, we examined the effects of PHD inhibition in a mouse model of moderate T9 contusive SCI in which white matter damage is the primary driver of locomotor dysfunction. Pharmacological inhibition of PHDs using adaptaquin (AQ) moderately lowers acute induction of Atf4 and Chop mRNAs and prevents the acute decline of oligodendrocyte (OL) lineage mRNAs, but does not improve long-term recovery of hindlimb locomotion or increase chronic white matter sparing. Conditional genetic ablation of all three PHD isoenzymes in OLs did not affect Atf4, Chop or OL mRNAs expression levels, locomotor recovery, and white matter sparing after SCI. Hence, PHDs may not be suitable targets to improve outcomes in traumatic CNS pathologies that involve acute white matter injury.


Assuntos
Fator 4 Ativador da Transcrição/antagonistas & inibidores , Estresse do Retículo Endoplasmático , Locomoção , Pró-Colágeno-Prolina Dioxigenase/antagonistas & inibidores , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/fisiopatologia , Fator de Transcrição CHOP/antagonistas & inibidores , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Traumatismos da Medula Espinal/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo
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