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1.
Front Bioeng Biotechnol ; 11: 1150772, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36970613

RESUMO

Introduction: Glioblastoma (GBM) invasiveness and ability to infiltrate deep into the brain tissue is a major reason for the poor patient prognosis for this type of brain cancer. Behavior of glioblastoma cells, including their motility, and expression of invasion-promoting genes such as matrix metalloprotease-2 (MMP2), are strongly influenced by normal cells found in the brain parenchyma. Cells such as neurons may also be influenced by the tumor, as many glioblastoma patients develop epilepsy. In vitro models of glioblastoma invasiveness are used to supplement animal models in a search for better treatments, and need to combine capability for high-throughput experiments with capturing bidirectional interactions between GBM and brain cells. Methods: In this work, two 3D in vitro models of GBM-cortical interactions were investigated. A matrix-free model was created by co-culturing GBM and cortical spheroids, and a matrix-based model was created by embedding cortical cells and a GBM spheroid in Matrigel. Results: Rapid GBM invasion occurred in the matrix-based model, and was enhanced by the presence of cortical cells. Little invasion occurred in the matrix-free model. In both types of models, presence of GBM cells resulted in a significant increase in paroxysmal neuronal activity. Discussion: Matrix-based model may be better suited for studying GBM invasion in an environment that includes cortical cells, while matrix-free model may be useful in investigation of tumor-associated epilepsy.

2.
Mol Imaging ; 2021: 8874078, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194287

RESUMO

Introduction: Standard neuroimaging protocols for brain tumors have well-known limitations. The clinical use of additional modalities including amino acid PET (aaPET) and advanced MRI (aMRI) techniques (including DWI, PWI, and MRS) is emerging in response to the need for more accurate detection of brain tumors. In this systematic review of the past 2 years of the literature, we discuss the most recent studies that directly compare or combine aaPET and aMRI for brain tumor imaging. Methods: A PubMed search was conducted for human studies incorporating both aaPET and aMRI and published between July 2018 and August 2020. Results: A total of 22 studies were found in the study period. Recent studies of aaPET with DWI showed a superiority of MET, FET, FDOPA, and AMT PET for detecting tumor, predicting recurrence, diagnosing progression, and predicting survival. Combining modalities further improved performance. Comparisons of aaPET with PWI showed mixed results about spatial correlation. However, both modalities were able to detect high-grade tumors, identify tumor recurrence, differentiate recurrence from treatment effects, and predict survival. aaPET performed better on these measures than PWI, but when combined, they had the strongest results. Studies of aaPET with MRS demonstrated that both modalities have diagnostic potential but MET PET and FDOPA PET performed better than MRS. MRS suffered from some data quality issues that limited analysis in two studies, and, in one study that combined modalities, overall performance actually decreased. Four recent studies compared aaPET with emerging MRI approaches (such as CEST imaging, MR fingerprinting, and SISTINA), but the initial results remain inconclusive. Conclusions: aaPET outperformed the aMRI imaging techniques in most recent studies. DWI and PWI added meaningful complementary data, and the combination of aaPET with aMRI yielded the best results in most studies.


Assuntos
Aminoácidos , Neoplasias Encefálicas , Neoplasias Encefálicas/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Tomografia por Emissão de Pósitrons
3.
Int J Mol Sci ; 21(24)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322413

RESUMO

Current standard-of-care treatment for glioblastoma, the most common malignant primary central nervous system (CNS) tumor, consists of surgical resection followed by adjuvant chemotherapy and radiation (Stupp protocol), providing an overall median survival of 15 months. With additional treatment using tumor-treating fields (Optune® therapy, Novocure Ltd., Haifa, Israel), survival can be extended up to 20 months. In spite of significant progress in our understanding of the molecular pathogenesis, the prognosis for patients with malignant gliomas remains poor and additional treatment modalities are critically needed. Curcumin is a bright yellow pigment found in the rhizome of the widely utilized spice, turmeric (Curcuma longa). It has long been used in South Asian traditional medicines and has been demonstrated to have in vitro antioxidant, anti-inflammatory, and antiproliferative effects. Curcumin has been demonstrated to induce multiple cytotoxic effects in tumor cells including cell cycle arrest, apoptosis, autophagy, changes in gene expression, and disruption of molecular signaling. Additionally, curcumin has been shown to potentiate the effect of radiation on cancer cells, while exhibiting a protective effect on normal tissue. Curcumin's positive safety profile and widespread availability make it a promising compound for future clinical trials for high-grade gliomas.


Assuntos
Antineoplásicos/uso terapêutico , Curcumina/uso terapêutico , Glioblastoma/tratamento farmacológico , Animais , Anti-Inflamatórios/uso terapêutico , Curcuma , Humanos , Extratos Vegetais/uso terapêutico
4.
Lung India ; 36(3): 226-228, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31031343

RESUMO

This is a case report of an unusual cause of bilateral diaphragmatic palsy. A 54-year-old gentleman, presented to us with exertional dyspnea and chest heaviness for the past 6 months which had increased in the last 6 days. Dyspnea increased on lying down. He was diagnosed as pneumonia on the basis of X-ray and chest CT scan, received treatment for the same and responded to the therapy. However, breathlessness and hypercapnia persisted. He had unexplained hypercapnia for which extensive investigations were carried out. Neurological and cardiac assessments were essentially normal. On revisit clinical examination, he was found to have paradoxical diaphragmatic movement with respiration. Ultrasound of chest detected no diaphragmatic movement. Detailed history elicited that patient was fond of neck massage and neck cracking wherein his barber would bend his neck with jerk to either side after a haircut.After considering all possible etiologies; we concluded that it was a case of diaphragm palsy induced by barber neck manipulation, leading to Type-2 respiratory failure. The fact that the vital clues to the diagnosis were elicited by detailed history and thorough examination reinforces that history and clinical examination for doctors shall remain a very important tool for clinical diagnosis.

5.
J Neurosurg ; 128(2): 414-421, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28298023

RESUMO

OBJECTIVE Treatment for glioblastoma (GBM) remains largely unsuccessful, even with aggressive combined treatment via surgery, radiotherapy, and chemotherapy. Tumor treating fields (TTFs) are low-intensity, intermediate-frequency, alternating electric fields that have antiproliferative properties in vitro and in vivo. The authors provide an up-to-date review of the mechanism of action as well as preclinical and clinical data on TTFs. METHODS A systematic review of the literature was performed using the terms "tumor treating fields," "alternating electric fields," "glioblastoma," "Optune," "NovoTTF-100A," and "Novocure." RESULTS Preclinical and clinical data have demonstrated the potential efficacy of TTFs for treatment of GBM, leading to several pilot studies, clinical trials, and, in 2011, FDA approval for its use as salvage therapy for recurrent GBM and, in 2015, approval for newly diagnosed GBM. CONCLUSIONS Current evidence supports the use of TTFs as an efficacious, antimitotic treatment with minimal toxicity in patients with newly diagnosed and recurrent GBM. Additional studies are needed to further optimize patient selection, determine cost-effectiveness, and assess the full impact on quality of life.


Assuntos
Neoplasias Encefálicas/terapia , Terapia por Estimulação Elétrica/métodos , Glioblastoma/terapia , Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Humanos , Resultado do Tratamento
6.
Oxid Med Cell Longev ; 2016: 9324085, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27807473

RESUMO

Brain malignancies currently carry a poor prognosis despite the current multimodal standard of care that includes surgical resection and adjuvant chemotherapy and radiation. As new therapies are desperately needed, naturally occurring chemical compounds have been studied for their potential chemotherapeutic benefits and low toxicity profile. Curcumin, found in the rhizome of turmeric, has extensive therapeutic promise via its antioxidant, anti-inflammatory, and antiproliferative properties. Preclinical in vitro and in vivo data have shown it to be an effective treatment for brain tumors including glioblastoma multiforme. These effects are potentiated by curcumin's ability to induce G2/M cell cycle arrest, activation of apoptotic pathways, induction of autophagy, disruption of molecular signaling, inhibition of invasion, and metastasis and by increasing the efficacy of existing chemotherapeutics. Further, clinical data suggest that it has low toxicity in humans even at large doses. Curcumin is a promising nutraceutical compound that should be evaluated in clinical trials for the treatment of human brain tumors.


Assuntos
Anti-Inflamatórios/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Curcumina/uso terapêutico , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Autofagia/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Ensaios Clínicos como Assunto , Curcumina/química , Curcumina/farmacologia , Portadores de Fármacos/química , Humanos , Invasividade Neoplásica/prevenção & controle
7.
Adv Neurobiol ; 12: 79-94, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27651249

RESUMO

Inflammation of the brain is one of the most highly researched yet mysterious areas in modern day neurology. The process of inflammation is a normal mechanism of wound healing that can result from acute injuries such as traumas or can be caused by genetic/environmental factors. After the initial insult, the immune system defenses, specifically microglial cells, are activated in order to combat the infection or injury. However, prolonged or chronic inflammation is often deleterious due mainly to accumulation of free reactive oxygen species (ROS) and other pro-inflammatory cytokines in the brain FADDIN EN.CITE. Plant-derived natural compounds have the potential to ameliorate the causes and symptoms of neuroinflammation, due to their various anti-oxidant and anti-inflammatory activities, without completely muting the immune defenses. Scutellaria is a perennial plant in the mint family that has been used to treat diseases in Asia and Eastern Europe throughout history. This chapter reviews the active components of various Scutellaria species and their mechanisms of action to prevent chronic neurologic disorders involving neuroinflammation and neurodegeneration.


Assuntos
Doenças do Sistema Nervoso/terapia , Extratos Vegetais/uso terapêutico , Scutellaria/química , Ásia , Europa Oriental , Humanos , Microglia/efeitos dos fármacos , Extratos Vegetais/farmacologia
8.
Cancer Immunol Immunother ; 61(5): 701-11, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22057676

RESUMO

A number of studies have implicated tumor-induced T(reg) cell activity in the sub-optimal response to therapeutic vaccines. Development of neo-adjuvant strategies targeting T(reg) cells is therefore imperative. Scutellaria extracts or constituent flavonoids have shown encouraging efficacy against various tumors, including gliomas, in both pre-clinical and clinical studies. We report here, for the first time, that Scutellaria ocmulgee leaf extract (SocL) and flavonoid wogonin could inhibit TGF-ß1-induced T(reg) activity in malignant gliomas. F344 rats, subcutaneously transplanted with F98 gliomas, were treated with SocL. There was a significant inhibition of intra-tumoral TGF-ß1 and T(reg) cell frequency as well as peripheral blood TGF-ß1 levels in SocL-treated animals compared to the controls. SocL extract and wogonin also inhibited glioma-induced, TGF-ß1-mediated T(reg) activity in vitro. SocL extract and wogonin also inhibited the secretion of IL-10 in T(reg) culture; whereas the level of IL-2 was either unchanged or marginally enhanced. We also observed an inhibition of Smad-3, GSK-3ß and ERK1/2 signaling by SocL and wogonin in T(reg) cells, while phosphorylation of P38 MAPK was considerably enhanced, indicating that SocL or wogonin could inhibit the T cells' response to TGF-ß1 via modulation of both Smad and non-Smad signaling pathways. Overall, this study suggests that Scutellaria can potentially reverse tumor-mediated immune suppression via inhibition of TGF-ß1 secretion as well as via inhibition of T cells' response to TGF-ß1. This may provide an opportunity for developing a novel adjuvant therapeutic strategy for malignant gliomas, combining Scutellaria with immunotherapy and chemo/radio-therapeutic regimen, which could potentially improve the disease outcome.


Assuntos
Flavanonas/farmacologia , Extratos Vegetais/farmacologia , Scutellaria/química , Linfócitos T Reguladores/efeitos dos fármacos , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Flavanonas/imunologia , Glioma/tratamento farmacológico , Glioma/imunologia , Glioma/metabolismo , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Quinase 3 da Glicogênio Sintase/imunologia , Glicogênio Sintase Quinase 3 beta , Interleucina-10/antagonistas & inibidores , Interleucina-10/imunologia , Interleucina-2/antagonistas & inibidores , Interleucina-2/imunologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Extratos Vegetais/imunologia , Folhas de Planta/química , Ratos , Transdução de Sinais , Proteína Smad3/antagonistas & inibidores , Proteína Smad3/imunologia , Linfócitos T Reguladores/imunologia , Fator de Crescimento Transformador beta1/imunologia , Fator de Crescimento Transformador beta1/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/imunologia
9.
J Neurosurg Spine ; 14(2): 198-208, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21184637

RESUMO

The execution technique of hanging, introduced by the Angle, Saxon, and Jute Germanic tribes during their invasions of the Roman Empire and Britain in the 5th century, has remained largely unchanged over time. The earliest form of a gallows was a tree on which prisoners were hanged. Despite the introduction of several modifications such as a trap door, the main mechanism of death remained asphyxiation. This created the opportunity for attempted revival after the execution, and indeed several well-known cases of survival following judicial hanging have been reported. It was not until the introduction of the standard drop by Dr. Samuel Haughton in 1866, and the so-called long drop by William Marwood in 1872 that hanging became a standard, humane means to achieve instantaneous death. Hangmen, however, fearing knot slippage, started substituting the subaural knot for the traditional submental knot. Subaural knots were not as effective, and cases of decapitation were recorded. Standardization of the long drop was further propagated by John Berry, an executioner who used mathematical calculations to estimate the correct drop length for each individual to be hanged. A British committee on capital sentences, led by Lord Aberdare, studied the execution method, and advocated for the submental knot. However, it was not until Frederic Wood-Jones published his seminal work in 1913 that cervical fractures were identified as the main mechanism of death following hanging in which the long drop and a submental knot were used. Schneider introduced the term "hangman's fracture" in 1965, and reported on the biomechanics and other similarities of the cervical fractures seen following judicial hangings and those caused by motor vehicle accidents.


Assuntos
Asfixia/história , Pena de Morte/história , Vértebras Cervicais/lesões , Medicina nas Artes , Pinturas/história , Fraturas da Coluna Vertebral/história , Fenômenos Biomecânicos , Europa (Continente) , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História Antiga , História Medieval , Humanos , Estados Unidos
10.
Planta Med ; 75(1): 41-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19031366

RESUMO

Scutellaria is a traditional herbal remedy with potential anti-cancer activity. The purpose of this study was to evaluate anticancer mechanisms of thirteen Scutellaria species and analyze their leaf, stem and root extracts for levels of common biologically active flavonoids: apigenin, baicalein, baicalin, chrysin, scutellarein, and wogonin. Malignant glioma, breast carcinoma and prostate cancer cells were used to determine tumor-specific effects of Scutellaria on cell proliferation, apoptosis and cell cycle progression, via the MTT assay and flow cytometry-based apoptosis and cell cycle analysis. The extracts and individual flavonoids inhibited the proliferation of malignant glioma and breast carcinoma cells without affecting primary or non-malignant cells. The flavonoids exhibited different mechanisms of anti-tumor activity as well as positive interactions. The antitumor mechanisms involved induction of apoptosis and cell cycle arrest at G1/G2. Of the extracts tested, leaf extracts of S. angulosa, S. integrifolia, S. ocmulgee and S. scandens were found to have strong anticancer activity. This study provides basis for further mechanistic and translational studies into adjuvant therapy of malignant tumors using Scutellaria leaf tissues.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Scutellaria/química , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Carcinoma/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Glioma/patologia , Humanos , Masculino , Folhas de Planta/química , Raízes de Plantas/química , Caules de Planta/química , Neoplasias da Próstata/patologia , Especificidade da Espécie
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