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1.
J Cell Physiol ; 234(7): 12042-12050, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30515824

RESUMO

Adipose-derived mesenchymal stem cells (ADMSCs) are easily accessible and are attractive mesenchymal stem cells for use in regenerative medicine; however their application is frequently restricted due to various challenges present in the environment they are administered. Therefore ADMSCs are preferably preconditioned with various stimulating factors to overcome the barriers developed in any pathological conditions. Here we used ADMSCs from rat adipose based on the abundance of positive markers and preconditioned the cells with extracts from Alpinate Oxyphyllae Fructus (AOF), a traditional Chinese herb used for antiaging, associated various health benefits. The preconditioned stem cells were tested for their potential to drive H9c2 from doxorubicin (Dox)-induced aging. The AOF-treated stem cells enriched stemness in ADMSCs with respect to their stem cells' positive marker, and enhanced their longevity mechanism and elevated the stem cell homing-associated C-X-C chemokine receptor type 7 (CXCR7). The AOF preconditioned stem cells, when cocultured with H9c2 cells, showed effective protection to Dox-induced senescence and stem cell homing to damaged H9c2 cells. The presence of AOF provided greater protective effects in the Dox environment. In addition, AOF-pretreated ADMSCs showed enhanced migration than those treated with AOF in Dox environment. Therefore, our results show that administration of AOF preconditioned stem cells is potentially an effective strategy in the management of aging-associated cardiac disorders.


Assuntos
Envelhecimento/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tecido Adiposo/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Doxorrubicina/farmacologia , Coração/efeitos dos fármacos , Ratos , Transdução de Sinais/efeitos dos fármacos
2.
Biotechnol Appl Biochem ; 62(5): 591-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25385323

RESUMO

Octamer-binding transcription factor 4 (Oct-4), an important gene regulating stem cell pluripotency, is well-known for its ability to reprogram somatic cells in vitro, either alone or in concert with other factors. The aim of this study was to assess the effect of ectopic expression of Oct human amniotic fluid stem cells. We developed a novel method for isolation of putative human amniotic fluid-derived multipotent stem cells. These cells showing mesenchymal stem cell phenotypes (human amniotic fluid-derived mesenchymal stem cells, hAFMSCs) were transfected with a plasmid carrying genes for Oct-4 and the green fluorescent protein (GFP). The stably transfected cells, hAFMSCs-Oct4/GFP, were selected by using G418 and found to express the GFP reporter gene under the control of Oct-4 promoter. We found that hAFMSCs developed by our method possess very high self-renewal ability (about 78 cumulative population doublings) and multilineage differentiation potency. Significantly, the hAFMSCs-Oct4/GFP cells showed enhanced expression of the three major pluripotency genes Oct-4, Nanog, and Sox-2, and increased colony-forming ability and growth rate compared with the parental hAFMSCs. We demonstrated that the ectopic expression of Oct-4 gene in hAFMSCs with high self-renewal ability could upregulate Nanog and Sox-2 gene expression and enhance cell growth rate and colony-forming efficiency. Therefore, the ectopic expression of Oct-4 could be a strategy to develop pluripotency in hAFMSCs for clinical applications.


Assuntos
Líquido Amniótico/citologia , Expressão Ectópica do Gene , Proteínas de Homeodomínio/genética , Células-Tronco Mesenquimais/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fatores de Transcrição SOXB1/genética , Regulação para Cima/genética , Biomarcadores/metabolismo , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Feminino , Humanos , Células-Tronco Mesenquimais/citologia , Proteína Homeobox Nanog , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Gravidez
3.
Anticancer Res ; 44(4): 1683-1693, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38537959

RESUMO

BACKGROUND/AIM: Prostate cancer (PCa) is lethal. Our aim in this retrospective cohort study was to use machine learning-based methodology to predict PCa risk in patients with benign prostate hyperplasia (BPH), identify potential risk factors, and optimize predictive performance. PATIENTS AND METHODS: The dataset was extracted from a clinical information database of patients at a single institute from January 2000 to December 2020. Patients newly diagnosed with BPH and prescribed alpha blockers/5-alpha-reductase inhibitors were enrolled. Patients were excluded if they had a previous diagnosis of any cancer or were diagnosed with PCa within 1 month of enrolment. The study endpoint was PCa diagnosis. The study utilized the extreme gradient boosting (XGB), support vector machine (SVM) and K-nearest neighbors (KNN) machine-learning algorithms for analysis. RESULTS: The dataset used in this study included 5,122 medical records of patients with and without PCa, with 19 patient characteristics. The SVM and XGB models performed better than the KNN model in terms of accuracy and area under curve. Local interpretable model-agnostic explanation and Shapley additive explanations analysis showed that body mass index (BMI) and late prostate-specific antigen (PSA) were important features for the SVM model, while PSA velocity, late PSA, and BMI were important features for the XGB model. Use of 5-alpha-reductase inhibitor was associated with a higher incidence of PCa, with similar survival outcomes compared to non-users. CONCLUSION: Machine learning can enhance personalized PCa risk assessments for patients with BPH but more research is necessary to refine these models and address data biases. Clinicians should use them as supplementary tools alongside traditional screening methods.


Assuntos
Hiperplasia Prostática , Neoplasias da Próstata , Masculino , Humanos , Próstata , Antígeno Prostático Específico , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/complicações , Estudos Retrospectivos , Hiperplasia , Detecção Precoce de Câncer , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/complicações , Algoritmos , Aprendizado de Máquina , Oxirredutases
4.
Nat Methods ; 6(10): 733-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19718031

RESUMO

We developed a method for somatic cell nuclear transfer in zebrafish using laser-ablated metaphase II eggs as recipients, the micropyle for transfer of the nucleus and an egg activation protocol after nuclear reconstruction. We produced clones from cells of both embryonic and adult origins, although the latter did not give rise to live adult clones.


Assuntos
Engenharia Genética/métodos , Células Híbridas/transplante , Peixe-Zebra/anatomia & histologia , Peixe-Zebra/genética , Animais , Técnicas de Transferência Nuclear
5.
Biotechnol Appl Biochem ; 59(3): 262-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23586837

RESUMO

A tumorigenic cell line with estrogen receptor and HER2 expression (ER/HER2⁺), R2N1d, was developed from a human breast epithelial cell type with stem cell characteristics in a growth factor/hormone-deprived cell culture condition. This study was undertaken to test whether tumor growth and other biological effects could be induced by estrogen in this cell line. The results clearly show that estrogen treatment greatly promoted the tumor growth of R2N1d cells in immune-deficient mice. Estrogen treatment of R2N1d cells in vitro was also found to induce other phenotypic changes related to breast carcinogenesis, that is, 1) the induction of epithelial-mesenchymal transition (EMT) shown by molecular and functional marker changes; 2) a significant increase of the CD44(high)/CD24(-/low) stem cell population; 3) the enhancement of cell growth rate and colony-forming ability; and 4) the acquisition of metastatic ability, that is, increased cell migration and invasiveness. From these results, we conclude that 1) estrogen could induce EMT and cancer stem cells and promote tumor growth in ER⁺/HER2⁺ cells known to be derived from human breast epithelial stem cells, and 2) normal stem cells could give rise to cancer stem cells.


Assuntos
Células Epiteliais/citologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Estradiol/farmacologia , Receptor ErbB-2/genética , Receptores de Estrogênio/genética , Células-Tronco/citologia , Animais , Neoplasias da Mama/patologia , Adesão Celular , Linhagem Celular Tumoral , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Nus
6.
Sci Rep ; 12(1): 3814, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264581

RESUMO

We present a new lossy compression algorithm for statistical floating-point data through a representation learning with binary variables. The algorithm finds a set of basis vectors and their binary coefficients that precisely reconstruct the original data. The optimization for the basis vectors is performed classically, while binary coefficients are retrieved through both simulated and quantum annealing for comparison. A bias correction procedure is also presented to estimate and eliminate the error and bias introduced from the inexact reconstruction of the lossy compression for statistical data analyses. The compression algorithm is demonstrated on two different datasets of lattice quantum chromodynamics simulations. The results obtained using simulated annealing show 3-3.5 times better compression performance than the algorithm based on neural-network autoencoder. Calculations using quantum annealing also show promising results, but performance is limited by the integrated control error of the quantum processing unit, which yields large uncertainties in the biases and coupling parameters. Hardware comparison is further studied between the previous generation D-Wave 2000Q and the current D-Wave Advantage system. Our study shows that the Advantage system is more likely to obtain low-energy solutions for the problems than the 2000Q.

7.
Dement Geriatr Cogn Disord ; 32(1): 1-10, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21811073

RESUMO

PURPOSE: This study was designed to investigate the specific cerebral blood flow (CBF) pattern in patients with idiopathic normal-pressure hydrocephalus (iNPH) and a predictive value for shunt responsiveness in a multicenter study (Study of Idiopathic Normal-Pressure Hydrocephalus on Neurological Improvement: SINPHONI). METHODS: Eighty-four iNPH patients underwent shunt operations using MRI selection criteria from the SINPHONI and were subjected to CBF single photon emission computed tomography (SPECT). The perfusion patterns on SPECT were classified: anterior-dominant CBF reduction type (A type), posterior-dominant CBF reduction type (P type), and mixed or diffuse CBF reduction type (M type). The predictive value of the CBF pattern for favorable shunt outcome was evaluated. RESULTS: Favorable outcomes were obtained in 76% (64/84) of patients, and shunt responsiveness was achieved in 85% (71/84) of patients. Areas of severely reduced relative CBF were demonstrated around the corpus callosum and in the sylvian fissure area, which included the effects of dilatations of the ventricles and sylvian fissures and relatively increased perfusion in the medial and lateral frontal, parietal, and occipital areas at high convexity. Forty-nine (58%) cases were A type, 25 (30%) cases were M type, and 10 (12%) cases were P type. A, M, and P type cases exhibited 83, 84, and 90% positive predictive values for shunt responsiveness, respectively. Mean modified Rankin scale and Mini-Mental State Examination scores of the A type group were significantly better than those of other groups. CONCLUSION: The iNPH patients showed various patterns of CBF reduction, but there was no significant difference in the predictive value among the three patterns, though CBF reduction patterns may suggest a severe condition of iNPH.


Assuntos
Hidrocefalia de Pressão Normal/diagnóstico por imagem , Hidrocefalia de Pressão Normal/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Anfetaminas , Artéria Cerebral Anterior/fisiopatologia , Mapeamento Encefálico , Circulação Cerebrovascular/fisiologia , Feminino , Humanos , Hidrocefalia de Pressão Normal/cirurgia , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Artéria Cerebral Posterior/fisiopatologia , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos , Tamanho da Amostra , Tomografia Computadorizada de Emissão de Fóton Único , Resultado do Tratamento , Derivação Ventriculoperitoneal
8.
Biol Cell ; 102(3): 159-72, 2010 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-19895368

RESUMO

BACKGROUND INFORMATION: The common phenotypes of cancer and stem cells suggest that cancers arise from stem cells. Oestrogen is one of the few most important determinants of breast cancer, as shown by several lines of convincing evidence. We have previously reported a human breast epithelial cell type (Type 1 HBEC) with stem cell characteristics and ER alpha (oestrogen receptor alpha) expression. A tumorigenic cell line, M13SV1R2, was developed from this cell type after SV40 (simian virus 40) large T-antigen transfection and X-ray irradiation. The cell line, however, was not responsive to oestrogen for cell growth or tumour development. In the present study, we tested the hypothesis that deprivation of growth factors and hormones may change the tumorigenicity and oestrogen response of this cell line. RESULTS: The M13SV1R2 cells lost their tumorigenicity after culturing in a growth factor/hormone-deprived medium for >10 passages (referred to as R2d cells) concomitant with the expression of two tumour suppressor genes, namely those coding for maspin and alpha 6 integrin. However, these cells acquired oestrogen responsiveness in cell growth and tumour development. By immunocytochemistry, Western blotting and flow cytometry analysis, oestrogen treatment of R2d cells was found to induce many important effects related to breast carcinogenesis, namely: (i) the emergence of a subpopulation of cells expressing CD44+/high/CD24-/low breast tumour stem cell markers; (ii) the induction of EMT (epithelial-to-mesenchymal transition); (iii) the acquisition of metastatic ability; and (iv) the expression of COX-2 (cyclo-oxygenase-2) through a CD44-mediated mechanism. CONCLUSION: An oestrogen-responsive cell line with ER alpha and CD44+/CD24-/low expression can be derived from breast epithelial stem cells. The tumorigenicity and oestrogen response of these cells could depend on the cell culture conditions. The findings of this study have implications in regard to the origins of (1) ER alpha-positive breast cancers, (2) CD44+/CD24-/low breast tumour stem cells and (3) the metastatic ability of breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma/metabolismo , Transformação Celular Neoplásica/metabolismo , Células Epiteliais/metabolismo , Receptor alfa de Estrogênio/metabolismo , Células-Tronco Neoplásicas/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Testes de Carcinogenicidade , Carcinoma/genética , Técnicas de Cultura de Células , Desdiferenciação Celular/efeitos dos fármacos , Desdiferenciação Celular/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Meios de Cultura/química , Meios de Cultura/farmacologia , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Estrogênios/deficiência , Estrogênios/farmacologia , Feminino , Genes Supressores de Tumor/efeitos dos fármacos , Humanos , Receptores de Hialuronatos/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/deficiência , Metástase Neoplásica/fisiopatologia , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/efeitos dos fármacos
9.
Sci Rep ; 11(1): 383, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431895

RESUMO

Advances in understanding the temperature effect on water dynamics in cellular respiration are important for the modeling of integrated energy processes and metabolic rates. For more than half a century, experimental studies have contributed to the understanding of the catalytic role of water in respiration combustion, yet the detailed water dynamics remains elusive. We combine a super-Arrhenius model that links the temperature-dependent exponential growth rate of a population of plant cells to respiration, and an experiment on isotope labeled 18O2 uptake to H218O transport role and to a rate-limiting step of cellular respiration. We use Phosphofructokinase (PFK-1) as a prototype because this enzyme is known to be a pacemaker (a rate-limiting enzyme) in the glycolysis process of respiration. The characterization shows that PFK-1 water matrix dynamics are crucial for examining how respiration (PFK-1 tetramer complex breathing) rates respond to temperature change through a water and nano-channel network created by the enzyme folding surfaces, at both short and long (evolutionary) timescales. We not only reveal the nano-channel water network of PFK-1 tetramer hydration topography but also clarify how temperature drives the underlying respiration rates by mapping the channels of water diffusion with distinct dynamics in space and time. The results show that the PFK-1 assembly tetramer possesses a sustainable capacity in the regulation of the water network toward metabolic rates. The implications and limitations of the reciprocal-activation-reciprocal-temperature relationship for interpreting PFK-1 tetramer mechanisms are briefly discussed.

10.
Surg Neurol Int ; 12: 631, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35350828

RESUMO

Background: Intraventricular tumors can generally result in obstructive hydrocephalus as they grow. Rarely, however, some intraventricular tumors develop superficial siderosis (SS) and trigger hydrocephalus, even though the tumor has hardly grown. Here, we present an illustrative case of SS and nonocclusive hydrocephalus caused by subependymoma of the lateral ventricles. Case Description: A 78-year-old man with an intraventricular tumor diagnosed 7 years ago had been suffering from gait disturbance for 2 years. He also developed cognitive impairment. Intraventricular tumors showed little growth on annual magnetic resonance imaging (MRI). MRI T2-star weighted images (T2*WI) captured small intratumoral hemorrhages from the beginning of the follow-up. Three years before, at the same time as the onset of ventricular enlargement, T2*WI revealed low intensity in the whole tumor and cerebral surface. Subsequent follow-up revealed that this hemosiderin deposition had spread to the brain stem and cerebellar surface, and the ventricles had expanded further. Cerebrospinal fluid (CSF) examination revealed xanthochromia. The tumor was completely removed en bloc. Histopathological findings were consistent with those of subependymoma. Although CSF findings improved, SS and hydrocephalus did not improve. Therefore, the patient underwent a lumboperitoneal shunt for CSF diversion after tumor resection. Conclusion: Some intraventricular tumors cause SS and nonobstructive hydrocephalus due to microbleeding, even in the absence of tumor growth. T2*WI and, if necessary, timely CSF examination can allow identification of presymptomatic SS. This follow-up strategy may provide a favorable course by facilitating early intervention in patients with intraventricular lesions, not just subependymomas.

11.
Mol Cancer ; 9: 288, 2010 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-21044318

RESUMO

BACKGROUND: Cancer cells are believed to arise primarily from stem cells. CD44+/CD24(-) have been identified as markers for human breast cancer stem cells. Although, HER2 is a well known breast cancer oncogene, the mechanisms of action of this gene are not completely understood. Previously, we have derived immortal (M13SV1), weakly tumorigenic (M13SV1R2) and highly tumorigenic (M13SV1R2N1) cell lines from a breast epithelial cell type with stem cell phenotypes after successive SV40 large T-antigen transfection, X-ray irradiation and ectopic expression of HER2/C-erbB2/neu. Recently, we found that M13SV1R2 cells became non-tumorigenic after growing in a growth factor/hormone-deprived medium (R2d cells). RESULTS: In this study, we developed M13SV1R2N1 under the same growth factor/hormone-deprived condition (R2N1d cells). This provides an opportunity to analyze HER2 effect on gene expression associated with tumorigenesis by comparative study of R2d and R2N1d cells with homogeneous genetic background except HER2 expression. The results reveal distinct characters of R2N1d cells that can be ascribed to HER2: 1) development of fast-growing tumors; 2) high frequency of CD44+/CD24(-) cells (~50% for R2N1d vs. ~10% for R2d); 3) enhanced expression of COX-2, HDAC6 mediated, respectively, by MAPK and PI3K/Akt pathways, and many genes associated with inflammation, metastasis, and angiogenesis. Furthermore, HER2 expression can be down regulated in non-adhering R2N1d cells. These cells showed longer latent period and lower rate of tumor development compared with adhering cells. CONCLUSIONS: HER2 may induce breast cancer by increasing the frequency of tumor stem cells and upregulating the expression of COX-2 and HDAC6 that play pivotal roles in tumor progression.


Assuntos
Antígeno CD24/metabolismo , Ciclo-Oxigenase 2/metabolismo , Histona Desacetilases/metabolismo , Receptores de Hialuronatos/metabolismo , Células-Tronco Neoplásicas/metabolismo , Receptor ErbB-2/metabolismo , Animais , Western Blotting , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/genética , Feminino , Citometria de Fluxo , Desacetilase 6 de Histona , Histona Desacetilases/genética , Humanos , Imuno-Histoquímica , Camundongos , Camundongos SCID , Receptor ErbB-2/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
12.
Life Sci ; 257: 118019, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32629002

RESUMO

Parkinson's disease (PD) is a disease of the human nervous system with an onset, in the sixth and seventh decades of the human life. Chiefly perceived as progressive degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNpc) with the ensued loss of dopamine in the striatum and the presence of Lewy bodies, consisting of α-synuclein agglomeration. In which the neuronal bridge between substantia nigra and striatum plays an advent role in the motor system. Dilapidation of these neurons results in dopamine depletion which in-turn makes hay to PD. Eventually, the etiology and pathogenesis of PD were still on a hike of dilemma. Traditional Chinese medicine (TCM), including Chinese herbal remedies, acupuncture, and manipulative therapies, is commonly used as an adjunctive therapy in different diseases, particularly neurological diseases, in Asian countries. Additionally, TCM might improve the prognoses and the quality of life of patients with PD because it induces less adverse drug reactions. The present review describes research on the various neuroprotective components and herbal extracts from herbal medicines in the context of addressing the effects of PD.


Assuntos
Medicina Tradicional Chinesa/métodos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/terapia , Animais , Encéfalo/metabolismo , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Dopamina , Neurônios Dopaminérgicos/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Parte Compacta da Substância Negra/metabolismo , Substância Negra/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo , alfa-Sinucleína/metabolismo
13.
Int J Cancer ; 124(11): 2512-9, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19199359

RESUMO

The introduction of the tumorigenic v-Ha-ras oncogene-transformed rat liver epithelial cells (WBras), which is deficient in gap junctional intercellular communication (GJIC), into F344 rats, induces significant formation of hepatocellular tumors. GJIC plays a major role in maintaining tissue homeostasis. Using this in vivo tumor model system, we used 2-dimensional electrophoresis with isoelectric focusing in the first dimension and SDS-PAGE in the second dimension to globally identify proteins that are uniquely expressed in the livers of WBras-treated rats as compared to the sham control. Immunoblotting was used to identify Ras and Connexin43, which were the positive and negative marker proteins, respectively, of the introduced WBras cells. As predicted, immunoblotting indicated that the whole liver of tumor-bearing animals exhibited a decreased level of Connexin43 and an increased level of Ras. Connexin43 and GJIC were expressed and functional in normal liver, but not in the tumor. In addition to these 2 markers, an additional 4 proteins exhibited decreased levels and 2 proteins exhibited increased levels in the livers of tumor-bearing animals. N-Terminal sequencing analysis was used to identify these proteins, which were glucose-regulated protein 78, 2 isoforms of heat shock protein 60, and the beta-chain of ATP synthase for the down regulated proteins, and beta-Actin with a 46 amino acid deletion from its N-terminus and Vimentin with a 71 amino acid deletion from its N-terminus for the up regulated proteins. These data offer potentially new markers of liver tumorigenicity, particularly, Vimentin. (


Assuntos
Actinas/química , Genes ras , Neoplasias Hepáticas/química , Fígado/química , Vimentina/química , Animais , Comunicação Celular , Linhagem Celular , Conexina 43/análise , Eletroforese em Gel Bidimensional , Junções Comunicantes/fisiologia , Histocitoquímica , Fígado/diagnóstico por imagem , Neoplasias Hepáticas/etiologia , Masculino , Veia Porta , Ratos , Ratos Endogâmicos F344 , Transfecção , Ultrassonografia
14.
J Neurosurg ; 111(3): 610-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19284245

RESUMO

OBJECT: Cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) to acetazolamide were investigated prospectively in 162 patients with a proposed diagnosis of idiopathic normal-pressure hydrocephalus (NPH). The aim of this study was to assess the usefulness of the measurement of CBF and CVR in determining which patients would be likely to benefit from shunt placement. METHODS: The mean CBF of the whole brain was measured according to the Patlak plot method by using technetium-99m hexamethylpropyleneamine oxime. The CVR value was obtained from the response to administration of 500 mg acetazolamide and calculated as the percentage change from the baseline mean CBF value. RESULTS: One hundred forty-six patients (90.1%) responded to shunt placement ("responders"), but 16 patients (9.9%) did not ("nonresponders"). No significant difference in preoperative CBF was observed between responders and nonresponders. Preoperative CVR was significantly impaired (p<0.0025) in responders compared with healthy controls, but not in nonresponders. Responders with the incomplete triad had a significant reduction (p<0.001) in preoperative CVR, but not in preoperative CBF, compared with healthy controls. Responders with the complete triad had significantly lower preoperative CBF and CVR than those with the incomplete triad (p<0.01 and p<0.05, respectively). Postoperative CBF and CVR increased significantly (p<0.025 and p<0.001, respectively) in responders. CONCLUSIONS: Both CBF and CVR decrease with the development of NPH, suggesting that hemodynamic ischemia may be responsible for manifestation of the symptoms. Impaired CVR and reduced CBF with the development of symptoms can be proposed as diagnostic criteria for idiopathic NPH.


Assuntos
Acetazolamida/farmacologia , Circulação Cerebrovascular/efeitos dos fármacos , Hidrocefalia de Pressão Normal/fisiopatologia , Hidrocefalia de Pressão Normal/cirurgia , Acetazolamida/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Derivações do Líquido Cefalorraquidiano , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
15.
Sci Rep ; 9(1): 10258, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311997

RESUMO

Numerous scientific and engineering applications require numerically solving systems of equations. Classically solving a general set of polynomial equations requires iterative solvers, while linear equations may be solved either by direct matrix inversion or iteratively with judicious preconditioning. However, the convergence of iterative algorithms is highly variable and depends, in part, on the condition number. We present a direct method for solving general systems of polynomial equations based on quantum annealing, and we validate this method using a system of second-order polynomial equations solved on a commercially available quantum annealer. We then demonstrate applications for linear regression, and discuss in more detail the scaling behavior for general systems of linear equations with respect to problem size, condition number, and search precision. Finally, we define an iterative annealing process and demonstrate its efficacy in solving a linear system to a tolerance of 10-8.

16.
Stem Cells Dev ; 28(21): 1424-1433, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31495275

RESUMO

Dome formation can occur in cultured tubular epithelial cells originating from various tissues, including the mammary gland and the kidney. The isolation and characterization of normal kidney epithelial stem cells that give rise to dome-forming tubular cells have never been reported. We attempted to isolate and characterize canine kidney epithelial stem cells using a simple cell culture method that we have previously used to isolate other adult human stem cells. Dome-forming kidney epithelial cells were derived from dissociated adult canine kidney tissues that were cultured in a modified keratinocyte serum-free medium supplemented with N-acetyl-l-cysteine, l-ascorbic acid 2-phosphate, nicotinamide, and fetal bovine serum. These cells exhibited high self-renewal capacity in long-term culture (growth for >13 months and 30 cumulative population doublings) and exhibited characteristics of stem cells, including (1) deficiency in gap junctional intercellular communication, (2) anchorage-independent growth, (3) expression of stem cell markers octamer-binding transcription factor 4 and SRY (sex determining region Y)-box 2, (4) expression of cell surface markers CD24 and CD133, and (5) multipotent differentiation into osteoblasts, adipocytes, chondrocytes, and dome-forming tubular cells. Most of these characteristics are shared by the well-known canine renal tubule-derived immortalized Madin-Darby Canine Kidney cell line. Furthermore, the putative canine kidney stem cells developed in this study formed budding tubule-like organoids on Matrigel and required high cell density (>4,000 cells/cm2) for sustained growth and confluency for dome formation. The signal transducer and activator of transcription-3 (STAT3) phosphorylation inhibitor, AG490, inhibited colony-forming efficiency and dome formation, whereas lipopolysaccharide, an activator of STAT3, increased colony-forming efficiency in a dose-dependent manner. These results are consistent with the hypothesis that high cell density induces STAT3 expression, which promotes both stem cell self-renewal and differentiation into tubular cells. Our novel cell culture method should be useful for the future development of normal human kidney stem cells for clinical applications and for studying mechanisms of nephrotoxicity.


Assuntos
Células Epiteliais/citologia , Túbulos Renais/citologia , Células-Tronco Multipotentes/citologia , Fator de Transcrição STAT3/metabolismo , Antígeno AC133/metabolismo , Animais , Antígeno CD24/metabolismo , Linhagem Celular , Terapia Baseada em Transplante de Células e Tecidos/métodos , Cães , Inibidores Enzimáticos/farmacologia , Falência Renal Crônica/terapia , Lipopolissacarídeos , Células Madin Darby de Rim Canino , Fator 3 de Transcrição de Octâmero/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Tirfostinas/farmacologia
17.
Int J Oncol ; 54(2): 655-664, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30483770

RESUMO

The overall goal of the present study was to evaluate the chemotherapeutic and cancer­protective properties of D­erythro­sphingosine (sphingosine) and C2­ceramide using a human breast epithelial cell (HBEC) culture system, which represents multiple­stages of breast carcinogenesis. The HBEC model includes Type I HBECs (normal stem), Type II HBECs (normal differentiated) and transformed cells (immortal/non­tumorigenic cells and tumorigenic cells, which are transformed from the same parental normal stem cells). The results of the present study indicate that sphingosine preferentially inhibits proliferation and causes death of normal stem cells (Type I), tumorigenic cells, and MCF7 breast cancer cells, but not normal differentiated cells (Type II). In contrast to the selective anti­proliferative effects of sphingosine, C2­ceramide inhibits proliferation of normal differentiated cells as well as normal stem cells, tumorigenic cells, and MCF7 cancer cells with similar potency. Both sphingosine and C2­ceramide induce apoptosis in tumorigenic cells. Among the sphingosine stereoisomers (D­erythro, D­threo, L­erythro, and L­threo) and sphinganine that were tested, L­erythro­sphingosine most potently inhibits proliferation of tumorigenic cells. The inhibition of breast tumorigenic/cancer cell proliferation by sphingosine was accompanied by inhibition of telomerase activity. Sphingosine at non­cytotoxic concentrations, but not C2­ceramide, induces differentiation of normal stem cells (Type I), thereby reducing the number of stem cells that are more susceptible to neoplastic transformation. To the best of our knowledge, the present study demonstrates one of the first results that sphingosine can be a potential chemotherapeutic and cancer­protective agent, whereas C2­ceramide is not an ideal chemotherapeutic and cancer­protective agent due to its anti­proliferative effects on Type II HBECs and its inability to induce the differentiation of Type I to Type II HBECs.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Mama/efeitos dos fármacos , Esfingosina/análogos & derivados , Esfingosina/farmacologia , Mama/patologia , Neoplasias da Mama/patologia , Carcinogênese/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Feminino , Humanos , Células MCF-7 , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos
18.
Biotechnol Appl Biochem ; 51(Pt 4): 159-66, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18279148

RESUMO

Porcine mesenchymal stem cells have been isolated previously from bone marrow but not from adipose tissue. In the present study a new cell-culture method, using a low-calcium medium supplemented with N-acetyl-L-cysteine and L-ascorbic acid 2-phosphate (the PM2 medium) was developed to grow pASCs (porcine adipose-tissue-derived stem cells). The pASCs developed using the new medium showed a high growth rate and a high proliferation potential, as measured by a cumulative population doubling level (55) that was significantly higher than those reported for ASCs in the literature. These pASCs lacked gap-junctional intercellular communication and were capable of differentiation into three mesodermal lineages (i.e. adipocytes, osteoblasts and chondrocytes) and an ectodermal lineage (i.e. neural cells). Surprisingly, osteogenic ability, but not adipogenesis, was found to increase dramatically with increasing passages. The high proliferative and differentiation potential of these pASCs should facilitate the development of a large-animal model to study the use of ASCs in regenerative and reparative medicine.


Assuntos
Tecido Adiposo/citologia , Técnicas de Cultura de Células/métodos , Proliferação de Células , Células-Tronco Multipotentes/citologia , Acetilcisteína/química , Adipócitos/citologia , Animais , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Diferenciação Celular , Transdiferenciação Celular , Células Cultivadas , Condrócitos/citologia , Meios de Cultura/química , Feminino , Junções Comunicantes/metabolismo , Neurônios/citologia , Osteoblastos/citologia , Suínos
19.
J Agric Food Chem ; 56(9): 2977-84, 2008 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-18426216

RESUMO

The fully ripened fruit of Katsura-uri Japanese pickling melon ( Cucumis melo var. conomon) has rarely been used for food because the midripened fruit is utilized for making pickles, but the fully ripened fruit is no longer valuable for pickles due to the fruit body being too soft. We have considered the utilization of the fully ripened Katsura-uri fruit that may be used for nonpickling products, particularly if the fully ripened fruit demonstrated health benefits such as anticarcinogenic properties. The phytochemical extract from the fully ripened fruit of Katsura-uri Japanese pickling melon was purified via a bioassay-guided fractionation scheme, which was based on the induction of differentiation in a RCM-1 human colon cancer cell line. On the criteria of two differentiation markers (duct formation and alkaline phosphatase activity), the most potent fraction contained a compound identified as 3-methylthiopropionic acid ethyl ester, based on GC retention time, EI-MS, (1)H NMR, and (13)C NMR spectra. Previously, the role of 3-methylthiopropionic acid ethyl ester was considered as an odor producing compound in many fruits, but this study indicates potential medical benefits of this compound.


Assuntos
Anticarcinógenos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Cucumis melo/química , Frutas/química , Propionatos/isolamento & purificação , Propionatos/farmacologia , Idoso , Fosfatase Alcalina/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectroscopia de Ressonância Magnética
20.
PLoS One ; 13(1): e0191070, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29351316

RESUMO

BACKGROUND: Peripheral innate immune response may induce sickness behavior through activating microglia, excessive cytokines production, and neuroinflammation. Dexmedetomidine (Dex) has anti-inflammatory effect. We investigated the effects of Dex on lipopolysaccharide (LPS)-induced neuroinflammation and sickness behavior in mice. MATERIALS AND METHODS: BALB/c mice were intraperitoneally (i.p.) injected with Dex (50 ug/kg) or vehicle. One hour later, the mice were injected (i.p.) with Escherichia coli LPS (0.33 mg/kg) or saline (n = 6 in each group). We analyzed the food and water intake, body weight loss, and sucrose preference of the mice for 24h. We also determined microglia activation and cytokines expression in the brains of the mice. In vitro, we determine cytokines expression in LPS-treated BV-2 microglial cells with or without Dex treatment. RESULTS: In the Dex-pretreated mice, LPS-induced sickness behavior (anorexia, weight loss, and social withdrawal) were attenuated and microglial activation was lower than vehicle control. The mRNA expression of TNF-α, MCP-1, indoleamine 2, 3 dioxygenase (IDO), caspase-3, and iNOS were increased in the brain of LPS-challenged mice, which were reduced by Dex but not vehicle. CONCLUSION: Dexmedetomidine diminished LPS-induced neuroinflammation in the mouse brain and modulated the cytokine-associated changes in sickness behavior.


Assuntos
Anedonia/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Dexmedetomidina/farmacologia , Comportamento de Doença/efeitos dos fármacos , Inflamação/induzido quimicamente , Lipopolissacarídeos/toxicidade , Animais , Apoptose/efeitos dos fármacos , Encéfalo/patologia , Inflamação/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microglia/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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