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1.
J Mater Sci Mater Med ; 34(3): 11, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36917271

RESUMO

The present study aimed to optimize magnetic fluid hyperthermia (MFH) protocols by standardizing MF incubation time, hyperthermic duration, magnetic field, and MFH sessions to achieve a better hyperthermic response for the profuse killing of human breast cancer cell cells MCF7. Magnetic nanoparticles and MF were characterized using XRD, VSM, and DLS. Induction heating was performed for 30 min at field strengths of 12.5 and 13.3 kA/m at a fixed frequency of 330 kHz with varying concentrations and incubation duration on MCF7 cells. Single and multiple sessions hyperthermia protocols were used to kill MCF7 cells and the cytotoxicity effect was analyzed using MTT assay. Single and multiple sessions MFH protocols were established to kill breast cancer cells utilizing 0.2 mg/mL MF at 13.3 kA/m field and 330 kHz frequency and maintaining the hyperthermic temperature of 43-45 °C for 30 min. The single session MFH revealed severe toxicity of MF leading to more than 75% of cell death after 24 h of MF incubation. Multiple sessions hyperthermia resulted in more than 90% killing of MCF7 cells after two consequent 3 h MF incubation with 3 h gap. Each 3 h of MF incubation was followed by 30 min of induction heating. Multiple sessions hyperthermia was effective in killing a larger cell population compared to the single session protocol. The results may help in optimizing protocols for the profuse killing of cancer cells of multiple origins, and aid in deciding futuristic in vivo MFH-based therapeutic strategies against breast cancer. Variation in MCF7 cells' viability due to HT, MF, and MF + HT in multiple sessions.


Assuntos
Neoplasias da Mama , Hipertermia Induzida , Humanos , Feminino , Células MCF-7 , Hipertermia Induzida/métodos , Neoplasias da Mama/terapia , Campos Magnéticos , Zinco
2.
Front Aging Neurosci ; 13: 767493, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867295

RESUMO

Abnormal accumulation of misfolded proteins in the endoplasmic reticulum and their aggregation causes inflammation and endoplasmic reticulum stress. This promotes accumulation of toxic proteins in the body tissues especially brain leading to manifestation of neurodegenerative diseases. The studies suggest that deregulation of proteostasis, particularly aberrant unfolded protein response (UPR) signaling, may be a common morbific process in the development of neurodegeneration. Curcumin, the mixture of low molecular weight polyphenolic compounds from turmeric, Curcuma longa has shown promising response to prevents many diseases including current global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and neurodegenerative disorders. The UPR which correlates positively with neurodegenerative disorders were found affected by curcumin. In this review, we examine the evidence from many model systems illustrating how curcumin interacts with UPR and slows down the development of various neurodegenerative disorders (ND), e.g., Alzheimer's and Parkinson's diseases. The recent global increase in ND patients indicates that researchers and practitioners will need to develop a new pharmacological drug or treatment to manage and cure these neurodegenerative diseases.

3.
Cells ; 10(9)2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34572076

RESUMO

Coronavirus disease 19 (COVID-19) is caused by an enveloped, positive-sense, single-stranded RNA virus, referred to as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which belongs to the realm Riboviria, order Nidovirales, family Coronaviridae, genus Betacoronavirus and the species Severe acute respiratory syndrome-related coronavirus. This viral disease is characterized by a myriad of varying symptoms, such as pyrexia, cough, hemoptysis, dyspnoea, diarrhea, muscle soreness, dysosmia, lymphopenia and dysgeusia amongst others. The virus mainly infects humans, various other mammals, avian species and some other companion livestock. SARS-CoV-2 cellular entry is primarily accomplished by molecular interaction between the virus's spike (S) protein and the host cell surface receptor, angiotensin-converting enzyme 2 (ACE2), although other host cell-associated receptors/factors, such as neuropilin 1 (NRP-1) and neuropilin 2 (NRP-2), C-type lectin receptors (CLRs), as well as proteases such as TMPRSS2 (transmembrane serine protease 2) and furin, might also play a crucial role in infection, tropism, pathogenesis and clinical outcome. Furthermore, several structural and non-structural proteins of the virus themselves are very critical in determining the clinical outcome following infection. Considering such critical role(s) of the abovementioned host cell receptors, associated proteases/factors and virus structural/non-structural proteins (NSPs), it may be quite prudent to therapeutically target them through a multipronged clinical regimen to combat the disease.


Assuntos
COVID-19 , Interações entre Hospedeiro e Microrganismos , SARS-CoV-2/patogenicidade , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , COVID-19/patologia , COVID-19/virologia , Sistemas de Liberação de Medicamentos , Furina/química , Furina/metabolismo , Humanos , Lectinas Tipo C/química , Lectinas Tipo C/metabolismo , Estrutura Molecular , Neuropilinas/química , Neuropilinas/metabolismo , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , Receptores Virais/química , Receptores Virais/metabolismo , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Resultado do Tratamento , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Internalização do Vírus
4.
Sci Rep ; 10(1): 15249, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943662

RESUMO

Self-regulating temperature-controlled nanoparticles such as Mn-Zn ferrite nanoparticles based magnetic fluid can be a better choice for magnetic fluid hyperthermia because of its controlled regulation of hyperthermia temperature window of 43-45 °C. To test this hypothesis magnetic fluid with said properties was synthesized, and its effect on cervical and breast cancer cell death was studied. We found that the hyperthermia window of 43-45 °C was maintained for one hour at the smallest possible concentration of 0.35 mg/mL without altering the magnetic field applicator parameters. Their hyperthermic effect on HeLa and MCF7 was investigated at the magnetic field of 15.3 kA/m and frequency 330 kHz, which is close to the upper safety limit of 5 * 109 A/m s. We have tested the cytotoxicity of synthesized Mn-Zn ferrite fluid using MTT assay and the results were validated by trypan blue dye exclusion assay that provides the naked eye microscopic view of actual cell death. Since cancer cells tend to resist treatment and show re-growth, we also looked into the effect of multiple sessions hyperthermia using a 24 h window till 72 h using trypan blue assay. The multiple sessions of hyperthermia showed promising results, and it indicated that a minimum of 3 sessions, each of one-hour duration, is required for the complete killing of cancer cells. Moreover, to simulate an in vivo cellular environment, a phantom consisting of magnetic nanoparticles dispersed in 1 and 5% agarose gel was constituted and studied. These results will help to decide the magnetic fluid based hyperthermic therapeutic strategies using temperature-sensitive magnetic fluid.


Assuntos
Neoplasias da Mama/terapia , Hipertermia Induzida/métodos , Nanopartículas Magnéticas de Óxido de Ferro/administração & dosagem , Neoplasias do Colo do Útero/terapia , Neoplasias da Mama/patologia , Morte Celular , Sobrevivência Celular , Meios de Cultura , Feminino , Compostos Férricos/administração & dosagem , Compostos Férricos/química , Células HeLa , Temperatura Alta/uso terapêutico , Humanos , Técnicas In Vitro , Células MCF-7 , Campos Magnéticos , Nanopartículas Magnéticas de Óxido de Ferro/química , Compostos de Manganês/administração & dosagem , Compostos de Manganês/química , Imagens de Fantasmas , Sefarose , Neoplasias do Colo do Útero/patologia , Compostos de Zinco/administração & dosagem , Compostos de Zinco/química
5.
J Neurosci ; 35(39): 13475-86, 2015 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-26424892

RESUMO

Brains of adult monkeys with chronic lesions of dorsal columns of spinal cord at cervical levels undergo large-scale reorganization. Reorganization results in expansion of intact chin inputs, which reactivate neurons in the deafferented hand representation in the primary somatosensory cortex (area 3b), ventroposterior nucleus of the thalamus and cuneate nucleus of the brainstem. A likely contributing mechanism for this large-scale plasticity is sprouting of axons across the hand-face border. Here we determined whether such sprouting takes place in area 3b. We first determined the extent of intrinsic corticocortical connectivity between the hand and the face representations in normal area 3b. Small amounts of neuroanatomical tracers were injected in these representations close to the electrophysiologically determined hand-face border. Locations of the labeled neurons were mapped with respect to the detailed electrophysiological somatotopic maps and histologically determined hand-face border revealed in sections of the flattened cortex stained for myelin. Results show that intracortical projections across the hand-face border are few. In monkeys with chronic unilateral lesions of the dorsal columns and expanded chin representation, connections across the hand-face border were not different compared with normal monkeys. Thalamocortical connections from the hand and face representations in the ventroposterior nucleus to area 3b also remained unaltered after injury. The results show that sprouting of intrinsic connections in area 3b or the thalamocortical inputs does not contribute to large-scale cortical plasticity. Significance statement: Long-term injuries to dorsal spinal cord in adult primates result in large-scale somatotopic reorganization due to which chin inputs expand into the deafferented hand region. Reorganization takes place in multiple cortical areas, and thalamic and medullary nuclei. To what extent this brain reorganization due to dorsal column injuries is related to axonal sprouting is not known. Here we show that reorganization of primary somatosensory area 3b is not accompanied with either an increase in intrinsic cortical connections between the hand and face representations, or any change in thalamocortical inputs to these areas. Axonal sprouting that causes reorganization likely takes place at subthalamic levels.


Assuntos
Face , Mãos/inervação , Córtex Somatossensorial/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Tálamo/fisiopatologia , Vias Aferentes/fisiopatologia , Animais , Doença Crônica , Vias Eferentes/fisiopatologia , Feminino , Lateralidade Funcional , Macaca mulatta , Masculino , Vias Neurais/fisiopatologia , Plasticidade Neuronal , Reconhecimento Psicológico , Vias Visuais/fisiopatologia
6.
J Comp Neurol ; 522(3): 528-45, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23853077

RESUMO

In primates, the motor cortex consists of at least seven different areas, which are involved in movement planning, coordination, initiation, and execution. However, for rats, only the primary motor cortex has been well described. A rostrally located second motor area has been proposed, but its extent, organization, and even definitive existence remain uncertain. Only a rostral forelimb area (RFA) has been definitively described, besides few reports of a rostral hindlimb area. We have previously proposed existence of a second whisker area, which we termed the rostral whisker area (RWA), based on its differential response to intracortical microstimulation compared with the caudal whisker area (CWA) in animals under deep anesthesia (Tandon et al. [2008] Eur J Neurosci 27:228). To establish that RWA is distinct from the caudally contiguous CWA, we determined sources of thalamic inputs to the two proposed whisker areas. Sources of inputs to RFA, caudal forelimb area (CFA), and caudal hindlimb region were determined for comparison. The results show that RWA and CWA can be distinguished based on differences in their thalamic inputs. RWA receives major projections from mediodorsal and ventromedial nuclei, whereas the major projections to CWA are from the ventral anterior, ventrolateral, and posterior nuclei. Moreover, the thalamic nuclei that provide major inputs to RWA are the same as for RFA, and the nuclei projecting to CWA are same as for CFA. The results suggest that rats have a second rostrally located motor area with RWA and RFA as its constituents.


Assuntos
Córtex Motor/fisiologia , Vias Neurais/fisiologia , Tálamo/fisiologia , Vibrissas/inervação , Animais , Contagem de Células , Dextranos/metabolismo , Feminino , Fluoresceínas/metabolismo , Masculino , Córtex Motor/citologia , Neurônios/metabolismo , Estimulação Física , Ratos , Ratos Long-Evans , Rodaminas/metabolismo , Núcleos Talâmicos/citologia , Núcleos Talâmicos/metabolismo
7.
J Comput Neurosci ; 27(1): 55-64, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19137420

RESUMO

Simultaneous recordings of spike trains from multiple single neurons are becoming commonplace. Understanding the interaction patterns among these spike trains remains a key research area. A question of interest is the evaluation of information flow between neurons through the analysis of whether one spike train exerts causal influence on another. For continuous-valued time series data, Granger causality has proven an effective method for this purpose. However, the basis for Granger causality estimation is autoregressive data modeling, which is not directly applicable to spike trains. Various filtering options distort the properties of spike trains as point processes. Here we propose a new nonparametric approach to estimate Granger causality directly from the Fourier transforms of spike train data. We validate the method on synthetic spike trains generated by model networks of neurons with known connectivity patterns and then apply it to neurons simultaneously recorded from the thalamus and the primary somatosensory cortex of a squirrel monkey undergoing tactile stimulation.


Assuntos
Potenciais de Ação/fisiologia , Neurônios/fisiologia , Processamento de Sinais Assistido por Computador , Algoritmos , Animais , Simulação por Computador , Eletrodos Implantados , Análise de Fourier , Modelos Neurológicos , Análise Multivariada , Estimulação Física , Saimiri , Córtex Somatossensorial/fisiologia , Tálamo/fisiologia , Percepção do Tato/fisiologia
8.
Planta Med ; 74(3): 296-301, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18300195

RESUMO

The trade in Phyllanthus material as bulk herb is rampant and mainly involves herbaceous species such as Phyllanthus amarus, P. fraternus, P . debilis and P. urinaria. These species are very important in herbal medicines and have varied activities. In India these species grow sympatrically and there are chances of deliberate or ignorant adulteration of crude drugs, lowering the efficiency of the medication for its intended purpose. Secondly, incorrect identification may also lead to erroneous reports on activities/molecules. To overcome this problem in crude drug (dry leaf powder) and compliment morphological identification in live plant, we have developed SCAR markers for all four species. In each species, we selected one fragment as being monomorphic between accessions but differing in size between species. These species-specific fragments were selected, cloned and sequenced. Based on the sequences, primer pairs were designed and amplification conditions standardized. SCAR markers were isolated from population DNA amplification profiles and validated by sequencing. The species-specific SCAR primers could retrieve the same size and sequence of fragments as in the RAPD profile. These fragments are 1150 bp, 317 bp, 980 bp and 550 bp in size for P. amarus, P. fraternus, P. debilis and P. urinaria, respectively. Additional fragments in P. debilis and P. urinaria indicate different alleles. The retrieval of same size and sequence of species-specific unique SCAR markers from the respective accessions (mixed DNA sample of same accessions) indicates the usefulness to study natural hybridization between the species in addition to adulteration.


Assuntos
Phyllanthus/classificação , Técnicas de Amplificação de Ácido Nucleico , Phyllanthus/genética , Folhas de Planta/classificação , Plantas Medicinais/classificação , Plantas Medicinais/genética
9.
J Comp Neurol ; 501(1): 95-120, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17206603

RESUMO

Connections of representations of the teeth and tongue in primary somatosensory cortex (area 3b) and adjoining cortex were revealed in owl, squirrel, and marmoset monkeys with injections of fluorescent tracers. Injection sites were identified by microelectrode recordings from neurons responsive to touch on the teeth or tongue. Patterns of cortical label were related to myeloarchitecture in sections cut parallel to the surface of flattened cortex, and to coronal sections of the thalamus processed for cytochrome oxidase (CO). Cortical sections revealed a caudorostral series of myelin dense ovals (O1-O4) in area 3b that represent the periodontal receptors of the contralateral teeth, the contralateral tongue, the ipsilateral teeth, and the ipsilateral tongue. The ventroposterior medial subnucleus, VPM, and the ventroposterior medial parvicellular nucleus for taste, VPMpc, were identified in the thalamic sections. Injections placed in the O1 oval representing teeth labeled neurons in VPM, while injections in O2 representing the tongue labeled neurons in both VPMpc and VPM. These injections also labeled adjacent part of areas 3a and 1, and locations in the lateral sulcus and frontal lobe. Callosally, connections of the ovals were most dense with corresponding ovals. Injections in the area 1 representation of the tongue labeled neurons in VPMpc and VPM, and ipsilateral area 3b ovals, area 3a, opercular cortex, and cortex in the lateral sulcus. Contralaterally, labeled neurons were mostly in area 1. The results implicate portions of areas 3b, 3a, and 1 in the processing of tactile information from the teeth and tongue, and possibly taste information from the tongue.


Assuntos
Platirrinos/fisiologia , Córtex Somatossensorial/fisiologia , Tálamo/fisiologia , Língua/fisiologia , Dente/fisiologia , Animais , Mapeamento Encefálico , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/fisiologia , Corpo Caloso/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Eletrofisiologia , Feminino , Corantes Fluorescentes , Imuno-Histoquímica , Masculino , Boca/fisiologia , Vias Neurais/fisiologia , Platirrinos/anatomia & histologia , Núcleos Posteriores do Tálamo/citologia , Núcleos Posteriores do Tálamo/metabolismo , Córtex Somatossensorial/anatomia & histologia , Tálamo/enzimologia
10.
Indian Heart J ; 56(2): 123-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15377133

RESUMO

BACKGROUND: Smoking, largely through increased oxidative stress, causes endothelial dysfunction which is an early key event in atherosclerosis. Smoking cessation and antioxidant vitamin therapy are shown to have beneficial role by restoring altered endothelial physiology. The present study was aimed to determine whether Terminalia arjuna, an Indian medicinal plant with potent antioxidant constituents, would improve endothelial dysfunction in smokers. METHODS AND RESULTS: Eighteen healthy male smokers (age 28.16+/-9.45 years) and equal number of age-matched non-smoker controls participated in the study. The baseline brachial artery reactivity studies were performed using high frequency ultrasound according to standard protocol under identical conditions to determine endothelium-dependent, flow-mediated dilation and endothelium-independent nitroglycerine-mediated dilation. The two groups were matched regarding age, body mass index, blood pressure, serum cholesterol, mean resting vessel diameters and post-occlusion flow velocities (all p=NS). While flow-mediated dilation was significantly impaired amongst smokers compared to controls (4.71+/-2.22 v. 11.75+/-5.94%, p <0.005), the nitroglycerine-mediated dilation was similar in the two groups (20.35+/-3.89 v. 19.68+/-3.74%, p=NS). Subsequently the smokers were given Terminalia arjuna (500 mg q8h) or matching placebo randomly in a double blind cross-over design for two weeks each, followed by repetition of brachial artery reactivity studies to determine various parameters including flow-mediated dilation after each period. There was no significant difference as regards vessel diameter and flow velocities between the two therapies. However, the flow-mediated dilation showed significant improvement from baseline values after Terrminalia arjuna therapy but not with placebo (9.31+/-3.74 v. 5.17+/-2.42%, p <0.005). CONCLUSIONS: Smokers have impaired endothelium-dependent but normal endothelium-independent vasodilation as determined by brachial artery reactivity studies. Further, Terrminalia arjuna therapy for two weeks leads to significant regression of this endothelial abnormality amongst smokers.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Endotélio Vascular/efeitos dos fármacos , Fitoterapia/métodos , Terminalia , Tabagismo/tratamento farmacológico , Adolescente , Adulto , Análise de Variância , Determinação da Pressão Arterial , Artéria Braquial/efeitos dos fármacos , Artéria Braquial/fisiologia , Doenças Cardiovasculares/etiologia , Estudos Cross-Over , Método Duplo-Cego , Endotélio Vascular/patologia , Seguimentos , Hemodinâmica/fisiologia , Humanos , Índia , Masculino , Probabilidade , Valores de Referência , Medição de Risco , Estudos de Amostragem , Fumar/efeitos adversos , Tabagismo/complicações , Tabagismo/diagnóstico , Resultado do Tratamento
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