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1.
J Cell Physiol ; 234(7): 12042-12050, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30515824

RESUMEN

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.


Asunto(s)
Envejecimiento/efectos de los fármacos , Longevidad/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Extractos Vegetales/farmacología , Tejido Adiposo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Doxorrubicina/farmacología , Corazón/efectos de los fármacos , Ratas , Transducción de Señal/efectos de los fármacos
2.
Biotechnol Appl Biochem ; 62(5): 591-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25385323

RESUMEN

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.


Asunto(s)
Líquido Amniótico/citología , Expresión Génica Ectópica , Proteínas de Homeodominio/genética , Células Madre Mesenquimatosas/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/genética , Factores de Transcripción SOXB1/genética , Regulación hacia Arriba/genética , Biomarcadores/metabolismo , Diferenciación Celular , Linaje de la Célula , Proliferación Celular , Femenino , Humanos , Células Madre Mesenquimatosas/citología , Proteína Homeótica Nanog , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Embarazo
3.
Anticancer Res ; 44(4): 1683-1693, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537959

RESUMEN

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.


Asunto(s)
Hiperplasia Prostática , Neoplasias de la Próstata , Masculino , Humanos , Próstata , Antígeno Prostático Específico , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/complicaciones , Estudios Retrospectivos , Hiperplasia , Detección Precoz del Cáncer , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/complicaciones , Algoritmos , Aprendizaje Automático , Oxidorreductasas
4.
Nat Methods ; 6(10): 733-5, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19718031

RESUMEN

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.


Asunto(s)
Ingeniería Genética/métodos , Células Híbridas/trasplante , Pez Cebra/anatomía & histología , Pez Cebra/genética , Animales , Técnicas de Transferencia Nuclear
5.
Biotechnol Appl Biochem ; 59(3): 262-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23586837

RESUMEN

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.


Asunto(s)
Células Epiteliales/citología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Estradiol/farmacología , Receptor ErbB-2/genética , Receptores de Estrógenos/genética , Células Madre/citología , Animales , Neoplasias de la Mama/patología , Adhesión Celular , Línea Celular Tumoral , Femenino , Citometría de Flujo , Humanos , Ratones , Ratones Desnudos
6.
Sci Rep ; 12(1): 3814, 2022 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-35264581

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-21811073

RESUMEN

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.


Asunto(s)
Hidrocéfalo Normotenso/diagnóstico por imagen , Hidrocéfalo Normotenso/fisiopatología , Anciano , Anciano de 80 o más Años , Anfetaminas , Arteria Cerebral Anterior/fisiopatología , Mapeo Encefálico , Circulación Cerebrovascular/fisiología , Femenino , Humanos , Hidrocéfalo Normotenso/cirugía , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Arteria Cerebral Posterior/fisiopatología , Valor Predictivo de las Pruebas , Radiofármacos , Tamaño de la Muestra , Tomografía Computarizada de Emisión de Fotón Único , Resultado del Tratamiento , Derivación Ventriculoperitoneal
8.
Biol Cell ; 102(3): 159-72, 2010 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-19895368

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama/metabolismo , Carcinoma/metabolismo , Transformación Celular Neoplásica/metabolismo , Células Epiteliales/metabolismo , Receptor alfa de Estrógeno/metabolismo , Células Madre Neoplásicas/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/genética , Pruebas de Carcinogenicidad , Carcinoma/genética , Técnicas de Cultivo de Célula , Desdiferenciación Celular/efectos de los fármacos , Desdiferenciación Celular/fisiología , Línea Celular , Línea Celular Tumoral , Transformación Celular Neoplásica/efectos de los fármacos , Transformación Celular Neoplásica/genética , Medios de Cultivo/química , Medios de Cultivo/farmacología , Ciclooxigenasa 2/efectos de los fármacos , Ciclooxigenasa 2/metabolismo , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Receptor alfa de Estrógeno/genética , Estrógenos/deficiencia , Estrógenos/farmacología , Femenino , Genes Supresores de Tumor/efectos de los fármacos , Humanos , Receptores de Hialuranos/metabolismo , Péptidos y Proteínas de Señalización Intercelular/deficiencia , Metástasis de la Neoplasia/fisiopatología , Células Madre Neoplásicas/citología , Células Madre Neoplásicas/efectos de los fármacos
9.
Sci Rep ; 11(1): 383, 2021 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-33431895

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-35350828

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-21044318

RESUMEN

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.


Asunto(s)
Antígeno CD24/metabolismo , Ciclooxigenasa 2/metabolismo , Histona Desacetilasas/metabolismo , Receptores de Hialuranos/metabolismo , Células Madre Neoplásicas/metabolismo , Receptor ErbB-2/metabolismo , Animales , Western Blotting , Línea Celular Tumoral , Ciclooxigenasa 2/genética , Femenino , Citometría de Flujo , Histona Desacetilasa 6 , Histona Desacetilasas/genética , Humanos , Inmunohistoquímica , Ratones , Ratones SCID , Receptor ErbB-2/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/genética , Transducción de Señal/fisiología
12.
Life Sci ; 257: 118019, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32629002

RESUMEN

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.


Asunto(s)
Medicina Tradicional China/métodos , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/terapia , Animales , Encéfalo/metabolismo , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Dopamina , Neuronas Dopaminérgicas/efectos de los fármacos , Humanos , Ratones , Ratones Endogámicos C57BL , Fármacos Neuroprotectores/farmacología , Porción Compacta de la Sustancia Negra/metabolismo , Sustancia Negra/efectos de los fármacos , Tirosina 3-Monooxigenasa/metabolismo , alfa-Sinucleína/metabolismo
13.
Int J Cancer ; 124(11): 2512-9, 2009 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-19199359

RESUMEN

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. (


Asunto(s)
Actinas/química , Genes ras , Neoplasias Hepáticas/química , Hígado/química , Vimentina/química , Animales , Comunicación Celular , Línea Celular , Conexina 43/análisis , Electroforesis en Gel Bidimensional , Uniones Comunicantes/fisiología , Histocitoquímica , Hígado/diagnóstico por imagen , Neoplasias Hepáticas/etiología , Masculino , Vena Porta , Ratas , Ratas Endogámicas F344 , Transfección , Ultrasonografía
14.
J Neurosurg ; 111(3): 610-7, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19284245

RESUMEN

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.


Asunto(s)
Acetazolamida/farmacología , Circulación Cerebrovascular/efectos de los fármacos , Hidrocéfalo Normotenso/fisiopatología , Hidrocéfalo Normotenso/cirugía , Acetazolamida/uso terapéutico , Anciano , Anciano de 80 o más Años , Derivaciones del Líquido Cefalorraquídeo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
15.
Sci Rep ; 9(1): 10258, 2019 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-31311997

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-31495275

RESUMEN

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.


Asunto(s)
Células Epiteliales/citología , Túbulos Renales/citología , Células Madre Multipotentes/citología , Factor de Transcripción STAT3/metabolismo , Antígeno AC133/metabolismo , Animales , Antígeno CD24/metabolismo , Línea Celular , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Perros , Inhibidores Enzimáticos/farmacología , Fallo Renal Crónico/terapia , Lipopolisacáridos , Células de Riñón Canino Madin Darby , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Factores de Transcripción SOXB1/metabolismo , Factor de Transcripción STAT3/antagonistas & inhibidores , Tirfostinos/farmacología
17.
Int J Oncol ; 54(2): 655-664, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30483770

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Mama/efectos de los fármacos , Esfingosina/análogos & derivados , Esfingosina/farmacología , Mama/patología , Neoplasias de la Mama/patología , Carcinogénesis/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Femenino , Humanos , Células MCF-7 , Células Madre Neoplásicas/efectos de los fármacos , Células Madre/efectos de los fármacos
18.
Biotechnol Appl Biochem ; 51(Pt 4): 159-66, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18279148

RESUMEN

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.


Asunto(s)
Tejido Adiposo/citología , Técnicas de Cultivo de Célula/métodos , Proliferación Celular , Células Madre Multipotentes/citología , Acetilcisteína/química , Adipocitos/citología , Animales , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Diferenciación Celular , Transdiferenciación Celular , Células Cultivadas , Condrocitos/citología , Medios de Cultivo/química , Femenino , Uniones Comunicantes/metabolismo , Neuronas/citología , Osteoblastos/citología , Porcinos
19.
J Agric Food Chem ; 56(9): 2977-84, 2008 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-18426216

RESUMEN

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.


Asunto(s)
Anticarcinógenos/farmacología , Diferenciación Celular/efectos de los fármacos , Cucumis melo/química , Frutas/química , Propionatos/aislamiento & purificación , Propionatos/farmacología , Anciano , Fosfatasa Alcalina/metabolismo , Línea Celular Tumoral , Neoplasias del Colon/patología , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Espectroscopía de Resonancia Magnética
20.
PLoS One ; 13(1): e0191070, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29351316

RESUMEN

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.


Asunto(s)
Anhedonia/efectos de los fármacos , Encéfalo/efectos de los fármacos , Dexmedetomidina/farmacología , Conducta de Enfermedad/efectos de los fármacos , Inflamación/inducido químicamente , Lipopolisacáridos/toxicidad , Animales , Apoptosis/efectos de los fármacos , Encéfalo/patología , Inflamación/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Microglía/efectos de los fármacos , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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