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1.
Chemistry ; 30(3): e202302919, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-37864779

RESUMEN

Under microwave (MW) irradiation at 150 °C in toluene and in the presence of nucleophiles (DMAP, triphenylphosphine and tetrahydrothiophene) 1-substituted 1-ethynyl-2-vinyldi- and tetrahydroisoquinolines undergo [3,3]-sigmatropic rearrangement providing pyrrolo[2,1-b][3]benzazepines in good yields. The replacement of toluene with acetonitrile directs the rearrangement towards the formation of 7,11b-dihydro-6H-pyrido[2,1-a]isoquinolines.

2.
Nature ; 557(7705): 375-380, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29743677

RESUMEN

The transcriptional programs that establish neuronal identity evolved to produce the rich diversity of neuronal cell types that arise sequentially during development. Remarkably, transient expression of certain transcription factors can also endow non-neural cells with neuronal properties. The relationship between reprogramming factors and the transcriptional networks that produce neuronal identity and diversity remains largely unknown. Here, from a screen of 598 pairs of transcription factors, we identify 76 pairs of transcription factors that induce mouse fibroblasts to differentiate into cells with neuronal features. By comparing the transcriptomes of these induced neuronal cells (iN cells) with those of endogenous neurons, we define a 'core' cell-autonomous neuronal signature. The iN cells also exhibit diversity; each transcription factor pair produces iN cells with unique transcriptional patterns that can predict their pharmacological responses. By linking distinct transcription factor input 'codes' to defined transcriptional outputs, this study delineates cell-autonomous features of neuronal identity and diversity and expands the reprogramming toolbox to facilitate engineering of induced neurons with desired patterns of gene expression and related functional properties.


Asunto(s)
Reprogramación Celular/genética , Neuronas/citología , Neuronas/metabolismo , Animales , Fibroblastos/citología , Fibroblastos/metabolismo , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Células Madre Pluripotentes Inducidas/citología , Células Madre Pluripotentes Inducidas/metabolismo , Ratones , Neuronas/efectos de los fármacos , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Factores de Transcripción/metabolismo , Transcriptoma/genética
3.
J Bacteriol ; 203(21): e0035921, 2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34424036

RESUMEN

The type 4 secretion system (T4SS) represents a bacterial nanomachine capable of trans-cell wall transportation of proteins and DNA and has attracted intense interest due to its roles in the pathogenesis of infectious diseases. In the current investigation, we uncovered three distinct gene clusters in Clostridioides difficile strain 630 encoding proteins structurally related to components of the VirB4/D4 type 4C secretion system from Streptococcus suis strain 05ZYH33 and located within sequences of conjugative transposons (CTn). Phylogenic analysis revealed that VirB4- and VirD4-like proteins of the CTn4 locus, on the one hand, and those of the CTn2 and CTn5 loci, on the other hand, fit into separate clades, suggesting specific roles of identified secretion system variants in the physiology of C. difficile. Our further study on VirB4- and VirD4-like products encoded by CTn4 revealed that both proteins possess Mg2+-dependent ATPase activity, form oligomers (most likely hexamers) in aqueous solutions, and rely on potassium but not sodium ions for the highest catalytic rate. VirD4 binds nonspecifically to DNA and RNA. The DNA-binding activity of VirD4 strongly decreased with the W241A variant. Mutations in the nucleotide sequences encoding presumable Walker A and Walker B motifs decreased the stability of the oligomers and significantly but not completely attenuated the enzymatic activity of VirB4. In VirD4, substitutions of amino acid residues in the peptides reminiscent of Walker structural motifs neither attenuated the enzymatic activity of the protein nor influenced the oligomerization state of the ATPase. IMPORTANCE C. difficile is a Gram-positive, anaerobic, spore-forming bacterium that causes life-threatening colitis in humans. Major virulence factors of the microorganism include the toxins TcdA, TcdB, and CDT. However, other bacterial products, including a type 4C secretion system, have been hypothesized to contribute to the pathogenesis of the infection and are considered possible virulence factors of C. difficile. In the current paper, we describe the structural organization of putative T4SS machinery in C. difficile and characterize its VirB4- and VirD4-like components. Our studies, in addition to its significance for basic science, can potentially aid the development of antivirulence drugs suitable for the treatment of C. difficile infection.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Proteínas Bacterianas/metabolismo , Clostridioides difficile/metabolismo , Regulación Bacteriana de la Expresión Génica/fisiología , Sistemas de Secreción Tipo IV/metabolismo , Adenosina Trifosfatasas/genética , Proteínas Bacterianas/genética , Clostridioides difficile/genética , Sistemas de Secreción Tipo IV/genética
4.
Ann Bot ; 127(7): 865-873, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-33556168

RESUMEN

BACKGROUND AND AIMS: Herbaria were recently advertised as reliable sources of information regarding historical changes in plant traits and biotic interactions. To justify the use of herbaria in global change research, we asked whether the characteristics of herbarium specimens have changed during the past centuries and whether these changes were due to shifts in plant collection practices. METHODS: We measured nine characteristics from 515 herbarium specimens of common European trees and large shrubs collected from 1558 to 2016. We asked botanists to rank these specimens by their scientific quality, and asked artists to rank these specimens by their beauty. KEY RESULTS: Eight of 11 assessed characteristics of herbarium specimens changed significantly during the study period. The average number of leaves in plant specimens increased 3-fold, whereas the quality of specimen preparation decreased. Leaf size negatively correlated with leaf number in specimens in both among-species and within-species analyses. The proportion of herbarium sheets containing plant reproductive structures peaked in the 1850s. The scientific value of herbarium specimens increased until the 1700s, but then did not change, whereas their aesthetic value showed no systematic trends. CONCLUSIONS: Our findings strongly support the hypothesis that many characteristics of herbarium specimens have changed systematically and substantially from the 16th to 21st centuries due to changes in plant collection and preservation practices. These changes may both create patterns which could be erroneously attributed to environmental changes and obscure historical trends in plant traits. The utmost care ought to be taken to guard against the possibility of misinterpretation of data obtained from herbarium specimens. We recommend that directional changes in characters of herbarium specimens which occurred during the past 150‒200 years, primarily in specimen size and in the presence of reproductive structures, are accounted for when searching for the effects of past environmental changes on plant traits.


Asunto(s)
Plantas , Árboles , Hojas de la Planta
5.
BMC Cancer ; 16: 105, 2016 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-26879245

RESUMEN

BACKGROUND: c-Met is the receptor tyrosine kinase for hepatocyte growth factor (HGF) encoded by the MET proto-oncogene. Aberrant activation of c-Met resulting from MET amplification and c-Met overexpression is associated with poor clinical outcome in multiple malignancies underscoring the importance of c-Met signaling in cancer progression. Several c-Met inhibitors have advanced to the clinic; however, the development of inhibitory c-Met-directed therapeutic antibodies has been hampered by inherent agonistic activity. METHOD: We generated and tested a bivalent anti-c-Met monoclonal antibody ABT-700 in vitro for binding potency and antagonistic activity and in vivo for antitumor efficacy in human tumor xenografts. Human cancer cell lines and gastric cancer tissue microarrays were examined for MET amplification by fluorescence in situ hybridization (FISH). RESULTS: ABT-700 exhibits a distinctive ability to block both HGF-independent constitutive c-Met signaling and HGF-dependent activation of c-Met. Cancer cells addicted to the constitutively activated c-Met signaling driven by MET amplification undergo apoptosis upon exposure to ABT-700. ABT-700 induces tumor regression and tumor growth delay in preclinical tumor models of gastric and lung cancers harboring amplified MET. ABT-700 in combination with chemotherapeutics also shows additive antitumor effect. Amplification of MET in human cancer tissues can be identified by FISH. CONCLUSIONS: The preclinical attributes of ABT-700 in blocking c-Met signaling, inducing apoptosis and suppressing tumor growth in cancers with amplified MET provide rationale for examining its potential clinical utility for the treatment of cancers harboring MET amplification.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antineoplásicos/farmacología , Proteínas Proto-Oncogénicas c-met/efectos de los fármacos , Proteínas Proto-Oncogénicas c-met/genética , Animales , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales/uso terapéutico , Antineoplásicos/metabolismo , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Amplificación de Genes , Humanos , Masculino , Ratones , Ratones SCID , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/genética , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Unión Proteica , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Ensayos Antitumor por Modelo de Xenoinjerto
6.
J Clin Med Res ; 16(4): 189-195, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38715560

RESUMEN

A 67-year-old woman was admitted to the Hematology Department in 2014 with complaints of weakness and a low-grade fever. After conducting various tests, it was confirmed that she had Waldenstrom macroglobulinemia. She underwent several rounds of chemotherapy and maintenance therapy with rituximab, which resulted in a good clinical response. However, in 2019, an abnormal growth in the soft tissues of patient's frontal region was discovered, which was diagnosed as lymphoplasmacytic lymphoma. This later progressed to an intracranial lesion. The patient underwent radiation therapy for both the extramedullary and intracranial growths, which had a positive effect. A year later, she developed a lesion in her lymph nodes and soft tissues of her right leg, which was confirmed to be a recurrence of Waldenstrom disease. She underwent further treatment and is currently in complete remission. This case highlights the rare occurrence of relapse in Waldenstrom disease and the challenges in diagnosing extramedullary lesions. It also demonstrates the success of modern treatment approaches using a combination of therapies.

7.
Biomolecules ; 13(6)2023 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-37371592

RESUMEN

In a previous study, we demonstrated that the Clostridioides difficile VirB4-like ATPase forms oligomers in vitro. In the current investigation, to study the observed phenomenon in more detail, we prepared a library of VirB4-derived peptides (delVirB4s) fused to a carrier maltose-binding protein (MBP). Using gel chromatography and polyacrylamide gel electrophoresis, we found a set of overlapping fragments that contribute most significantly to protein aggregation, which were represented as water-soluble oligomers with molecular masses ranging from ~300 kD to several megadaltons. Membrane filtration experiments, sucrose gradient ultracentrifugation, and dynamic light scattering measurements indicated the size of the soluble complex to be 15-100 nm. It was sufficiently stable to withstand treatment with 1 M urea; however, it dissociated in a 6 M urea solution. As shown by the changes in GFP fluorescence and the circular dichroism spectra, the attachment of the delVirB4 peptide significantly altered the structure of the partner MBP. The immunization of mice with the hybrid consisting of the selected VirB4-derived peptide and MBP, GST, or GFP resulted in increased production of specific antibodies compared to the peptide-free carrier proteins, suggesting significant adjuvant activity of the VirB4 fragment. This feature could be useful for the development of new vaccines, especially in the case of "weak" antigens that are unable to elicit a strong immune response by themselves.


Asunto(s)
Adenosina Trifosfatasas , Clostridioides difficile , Animales , Ratones , Adenosina Trifosfatasas/metabolismo , Clostridioides difficile/metabolismo , Proteínas Portadoras/metabolismo , Péptidos/metabolismo
8.
Stem Cells Dev ; 32(13-14): 387-397, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37166357

RESUMEN

Transplantation of human induced pluripotent stem cell-derived dopaminergic (iPSC-DA) neurons is a promising therapeutic strategy for Parkinson's disease (PD). To assess optimal cell characteristics and reproducibility, we evaluated the efficacy of iPSC-DA neuron precursors from two individuals with sporadic PD by transplantation into a hemiparkinsonian rat model after differentiation for either 18 (d18) or 25 days (d25). We found similar graft size and dopamine (DA) neuron content in both groups, but only the d18 cells resulted in recovery of motor impairments. In contrast, we report that d25 grafts survived equally as well and produced grafts rich in tyrosine hydroxylase-positive neurons, but were incapable of alleviating any motor deficits. We identified the mechanism of action as the extent of neurite outgrowth into the host brain, with d18 grafts supporting significantly more neurite outgrowth than nonfunctional d25 grafts. RNAseq analysis of the cell preparation suggests that graft efficacy may be enhanced by repression of differentiation-associated genes by REST, defining the optimal predifferentiation state for transplantation. This study demonstrates for the first time that DA neuron grafts can survive well in vivo while completely lacking the capacity to induce recovery from motor dysfunction. In contrast to other recent studies, we demonstrate that neurite outgrowth is the key factor determining graft efficacy and our gene expression profiling revealed characteristics of the cells that may predict their efficacy. These data have implication for the generation of DA neuron grafts for clinical application.


Asunto(s)
Neuronas Dopaminérgicas , Células Madre Pluripotentes Inducidas , Humanos , Ratas , Animales , Transcriptoma , Reproducibilidad de los Resultados , Diferenciación Celular/fisiología , Proyección Neuronal
9.
ACS Sustain Chem Eng ; 11(36): 13374-13386, 2023 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-37711764

RESUMEN

Permanent magnets are fundamental constituents in key sectors such as energy and transport, but also robotics, automatization, medicine, etc. High-performance magnets are based on rare earth elements (RE), included in the European list of critical raw materials list. The volatility of their market increased the research over the past decade to develop RE-free magnets to fill the large performance/cost gap existing between ferrites and RE-based magnets. The improvement of hard ferrites and Mn-Al-C permanent magnets plays into this important technological role in the near future. The possible substitution advantage was widely discussed in the literature considering both magnetic properties and economic aspects. To evaluate further sustainability aspects, the present paper gives a life cycle assessment quantifying the environmental gain resulting from the production of RE-free magnets based on traditional hexaferrite and Mn-Al-C. The analysis quantified an advantage of both magnets that overcomes the 95% in all the considered impact categories (such as climate change, ozone depletion, human toxicity) compared to RE-based technologies. The benefit also includes the health and safety of working time aspects, proving possible reduction of worker risks by 3-12 times. The results represent the fundamentals for the development of green magnets that are able to significantly contribute to an effective sustainable transition.

10.
Stem Cells Transl Med ; 11(6): 613-629, 2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35556144

RESUMEN

Fragile X Syndrome (FXS), the leading monogenic cause of intellectual disability and autism spectrum disorder, is caused by expansion of a CGG trinucleotide repeat in the 5'-UTR of the Fragile X Mental Retardation-1 (FMR1) gene. Epigenetic silencing of FMR1 results in loss of the Fragile X Mental Retardation Protein (FMRP). Although most studies to date have focused on excitatory neurons, recent evidence suggests that GABAergic inhibitory networks are also affected. To investigate human GABAergic neurogenesis, we established a method to reproducibly derive inhibitory neurons from multiple FXS and control human pluripotent stem cell (hPSC) lines. Electrophysiological analyses suggested that the developing FXS neurons had a delay in the GABA functional switch, a transition in fetal development that converts the GABAA channel's function from depolarization to hyperpolarization, with profound effects on the developing brain. To investigate the cause of this delay, we analyzed 14 400 single-cell transcriptomes from FXS and control cells at 2 stages of GABAergic neurogenesis. While control and FXS cells were similar at the earlier time point, the later-stage FXS cells retained expression of neuroblast proliferation-associated genes and had lower levels of genes associated with action potential regulation, synapses, and mitochondria compared with controls. Our analysis suggests that loss of FMRP prolongs the proliferative stage of progenitors, which may result in more neurons remaining immature during the later stages of neurogenesis. This could have profound implications for homeostatic excitatory-inhibitory circuit development in FXS, and suggests a novel direction for understanding disease mechanisms that may help to guide therapeutic interventions.


Asunto(s)
Trastorno del Espectro Autista , Síndrome del Cromosoma X Frágil , Células Madre Pluripotentes , Epigénesis Genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/metabolismo , Humanos , Neurogénesis , Células Madre Pluripotentes/metabolismo
11.
Front Cardiovasc Med ; 9: 862409, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35770217

RESUMEN

Background: Cardiac AL amyloidosis as a complication of multiple myeloma (MM) is a formidable life-threatening condition. The first-line therapy for both MM and systemic AL amyloidosis is proteasome inhibitors (PIs). Unfortunately, the use of PIs may lead to cardiovascular toxicity development, which requires specific cardio-oncology supervision. Case Report: A 57-year-old woman was admitted to a university hospital with clinical manifestation of progressive chronic heart failure. The patient had hypertension and no history of diabetes mellitus, myocardial infarction (MI), stroke, and arrhythmias. After a series of laboratory and instrumental examination methods, MM complicated by cardiac AL amyloidosis was proved. Upon specific cardio-oncology examination (NT-proBNP 4,274 pg/ml), ECHO showed systolic dysfunction, motion abnormalities in LV basal and middle segments, and a typical depositional myocardium pattern ("luminescence"); cardiac MRI revealed restrictive cardiomyopathy and specific hyperenhancement of the ventricles and atria; 24-h ECG showed QS-pattern in leads V1-V3 and unstable ventricular tachycardia (VT) paroxysms. Cardio-oncology consultation showed baseline cardiovascular risk was very high (≥20%), and cardioprotective therapy [iACE/ARBs, beta-blockers (BB), statins] was administered. The patient underwent VCD (bortezomib; cyclophosphamide; dexamethasone) chemotherapy (CMT) program. By the time of publication, the patient had received four CMT courses with a positive oncohematological and cardiovascular effect. Conclusion: In this clinical case, we described a complication of MM, which was rare according to the severity and manifestation with restrictive cardiomyopathy due to secondary cardiac amyloidosis. The case's features were difficulties in verifying the underlying disease and its own complication, and the complexity of patient management according to modern principles of cardio-oncology.

12.
J Blood Med ; 12: 431-434, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34135652

RESUMEN

Splenic marginal zone lymphoma (SMZL) is a type of non-Hodgkin's lymphoma (NL) that occurs in 2 out of 100 cases and is more common in women aged >60 years. A sluggish, asymptomatic course of the disease does not exclude transformation into a malignant form that occurs in 25% of patients with SMZL. Another equally important sign of an NL is thrombosis that occurs in 3.6% to 17.1% of the cases. In this report, we present a case of emergency splenectomy in a patient owing to difficulties in the diagnosis of SMZL, rapid onset of acute portal vein thrombosis, and the fulminant enlargement of the spleen accompanied by an increased risk of its rupture. Chronic hepatitis B was likely the trigger for transformation of the disease to an aggressive course. Portal vein thrombosis and the aggressive course of SMZL with rapid enlargement of the spleen and threat of its rupture in the background of viral hepatitis B required emergency splenectomy followed by anticoagulant, antiviral, and antitumor therapy.

13.
BMC Cancer ; 10: 432, 2010 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-20712890

RESUMEN

BACKGROUND: Cervical dysplasia and tumorigenesis have been linked with numerous chromosomal aberrations. The goal of this study was to evaluate 35 genomic regions associated with cervical disease and to select those which were found to have the highest frequency of aberration for use as probes in fluorescent in-situ hybridization. METHODS: The frequency of gains and losses using fluorescence in-situ hybridization were assessed in these 35 regions on 30 paraffin-embedded cervical biopsy specimens. Based on this assessment, 6 candidate fluorescently labeled probes (8q24, Xp22, 20q13, 3p14, 3q26, CEP15) were selected for additional testing on a set of 106 cervical biopsy specimens diagnosed as Normal, CIN1, CIN2, CIN3, and SCC. The data were analyzed on the basis of signal mean, % change of signal mean between histological categories, and % positivity. RESULTS: The study revealed that the chromosomal regions with the highest frequency of copy number gains and highest combined sensitivity and specificity in high-grade cervical disease were 8q24 and 3q26. The cytological application of these two probes was then evaluated on 118 ThinPrep samples diagnosed as Normal, ASCUS, LSIL, HSIL and Cancer to determine utility as a tool for less invasive screening. Using gains of either 8q24 or 3q26 as a positivity criterion yielded specificity (Normal +LSIL+ASCUS) of 81.0% and sensitivity (HSIL+Cancer) of 92.3% based on a threshold of 4 positive cells. CONCLUSIONS: The application of a FISH assay comprised of chromosomal probes 8q24 and 3q26 to cervical cytology specimens confirms the positive correlation between increasing dysplasia and copy gains and shows promise as a marker in cervical disease progression.


Asunto(s)
Cuello del Útero/patología , Aberraciones Cromosómicas , Cromosomas Humanos Par 3/genética , Cromosomas Humanos Par 8/genética , Variaciones en el Número de Copia de ADN/genética , Displasia del Cuello del Útero/genética , Neoplasias del Cuello Uterino/genética , Progresión de la Enfermedad , Femenino , Humanos , Hibridación Fluorescente in Situ , Pronóstico , Displasia del Cuello del Útero/patología , Neoplasias del Cuello Uterino/patología
14.
Sci Rep ; 10(1): 12298, 2020 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-32704145

RESUMEN

Information regarding plant damage by insects in the past is essential to explore impacts of climate change on herbivory. We asked whether insect herbivory measured from herbarium specimens reflects the levels of herbivory occurring in nature at the time of herbarium sampling. We compared herbivory measurements between herbarium specimens collected by botany students and ecological samples collected simultaneously by the authors by a method that minimized unconscious biases, and asked herbarium curators to select one of two plant specimens, which differed in leaf damage, for their collections. Both collectors and curators generally preferred specimens with lesser leaf damage, but the strength of this preference varied among persons. In addition, the differences in measured leaf damage between ecological samples and herbarium specimens varied among plant species and increased with the increase in field herbivory. Consequently, leaf damage in herbarium specimens did not correlate with the actual level of herbivory. We conclude that studies of herbarium specimens produce biased information on past levels of herbivory, because leaf damage measured from herbarium specimens not only underestimates field herbivory, but it is not proportional to the level of damage occurring in nature due to multiple factors that cannot be controlled in data analysis.


Asunto(s)
Herbivoria , Insectos , Plantas , Animales , Cambio Climático , Ecosistema , Bosques , Hojas de la Planta , Madera
15.
Can J Urol ; 16(4): 4726-32, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19671223

RESUMEN

BACKGROUND: The ability of aggressive tumors to form nonendothelial tumor cell-lined microvascular channels is known as "vasculogenic mimicry" (VM). VM channels are revealed as periodic acid-Schiff (PAS)-positive patterns, and in some tumors their presence predicts clinical outcomes. OBJECTIVE: We aimed to study VM channels in clear cell renal cell carcinoma (cRCC) tumors and explore their prognostic significance and relationship to other suggested prognostic factors such as thymidine phosphorylase (TP) and vascular endothelial growth factor (VEGF) expression. METHODS: We retrospectively studied 45 patients who had undergone radical nephrectomy for clinically confined cRCC (stage T2-T3NOMO) at the Russian Cancer Research Center. The tumor sections were reviewed for disease stage, nuclear grade, perirenal fat invasion, and lymph node involvement, and we performed immunohistochemical staining for VEGF and TP expression, and PAS staining. Disease-free survival probabilities were determined by Kaplan-Meier estimates and prognostic factors were evaluated by univariate analysis. RESULTS: PAS-positive patterns observed in the cRCC tumor included back-to-back closed loops, networks, arcs, and parallel patterns. There was a significant decrease in disease-free survival among patients with PAS-positive networks (p = 0.005), but not among patients with other PAS-positive patterns. TP expression was also a significant predictor of disease-free survival (p = 0.035), but this factor did not correlate with the presence of PAS-positive networks. Notably, in our small sample, the six patients whose tumors were positive for both factors had the highest risk of cancer recurrence. CONCLUSIONS: The presence of PAS-positive networks is an independent and relevant prognostic parameter for disease-free survival in patients with cRCC. Our data suggest that the combination of PAS-positive networks and TP expression may identify patients with the highest risk of cancer recurrence.


Asunto(s)
Carcinoma de Células Renales/metabolismo , Neoplasias Renales/metabolismo , Adulto , Anciano , Carcinoma de Células Renales/química , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Renales/química , Masculino , Persona de Mediana Edad , Reacción del Ácido Peryódico de Schiff , Pronóstico , Estudios Retrospectivos , Timidina Fosforilasa/análisis , Factor A de Crecimiento Endotelial Vascular/análisis
16.
Brain Res ; 1724: 146431, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31491420

RESUMEN

The hippocampus is involved in key neuronal circuits that underlie cognition, memory, and anxiety, and it is increasingly recognized as a vulnerable structure that contributes to the pathogenesis of HIV-associated neurocognitive disorder (HAND). However, the mechanisms responsible for hippocampal dysfunction in neuroHIV remain unknown. The present study used HIV transgenic (Tg) rats and patch-clamp electrophysiological techniques to study the effects of the chronic low-level expression of HIV proteins on hippocampal CA1 pyramidal neurons. The dorsal and ventral areas of the hippocampus are involved in different neurocircuits and thus were evaluated separately. We found a significant decrease in the intrinsic excitability of CA1 neurons in the dorsal hippocampus in HIV Tg rats by comparing neuronal spiking induced by current step injections and by dynamic clamp to simulate neuronal spiking activity. The decrease in excitability in the dorsal hippocampus was accompanied by a higher rate of excitatory postsynaptic currents (EPSCs), whereas CA1 pyramidal neurons in the ventral hippocampus in HIV Tg rats had higher EPSC amplitudes. We also observed a reduction of hyperpolarization-activated nonspecific cationic current (Ih) in both the dorsal and ventral hippocampus. Neurotoxic HIV proteins have been shown to increase neuronal excitation. The lower excitability of CA1 pyramidal neurons that was observed herein may represent maladaptive homeostatic plasticity that seeks to stabilize baseline neuronal firing activity but may disrupt neural network function and contribute to HIV-associated neuropsychological disorders, such as HAND and depression.


Asunto(s)
Complejo SIDA Demencia/fisiopatología , Región CA1 Hipocampal/metabolismo , Infecciones por VIH/fisiopatología , Animales , Potenciales Postsinápticos Excitadores/fisiología , Femenino , VIH/patogenicidad , Infecciones por VIH/metabolismo , Hipocampo/metabolismo , Memoria , Neuronas/efectos de los fármacos , Técnicas de Placa-Clamp/métodos , Células Piramidales/fisiología , Ratas , Ratas Transgénicas , Ratas Wistar
17.
Clin Cancer Res ; 25(11): 3259-3265, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30796037

RESUMEN

PURPOSE: Patients with glioblastoma (GBM) have a poor prognosis and are in desperate need of better therapies. As therapeutic decisions are increasingly guided by biomarkers, and EGFR abnormalities are common in GBM, thus representing a potential therapeutic target, we systematically evaluated methods of assessing EGFR amplification by multiple assays. Specifically, we evaluated correlation among fluorescence in situ hybridization (FISH), a standard assay for detecting EGFR amplification, with other methods.Experimental Design: Formalin-fixed, paraffin-embedded tumor samples were used for all assays. EGFR amplification was detected using FISH (N = 206) and whole-exome sequencing (WES, N = 74). EGFR mRNA expression was measured using reverse transcription-polymerase chain reaction (RT-PCR, N = 206) and transcriptome profiling (RNAseq, N = 64). EGFR protein expression was determined by immunohistochemistry (IHC, N = 34). Significant correlations among various methods were determined using Cohen's kappa (κ = 0.61-0.80 defines substantial agreement) or R 2 statistics. RESULTS: EGFR mRNA expression levels by RNA sequencing (RNAseq) and RT-PCR were highly correlated with EGFR amplification assessed by FISH (κ = 0.702). High concordance was also observed when comparing FISH to WES (κ = 0.739). RNA expression was superior to protein expression in delineating EGFR amplification. CONCLUSIONS: Methods for assessing EGFR mRNA expression (RT-PCR, RNAseq) and copy number (WES), but not protein expression (IHC), can be used as surrogates for EGFR amplification (FISH) in GBM. Collectively, our results provide enhanced understanding of available screening options for patients, which may help guide EGFR-targeted therapeutic approaches.


Asunto(s)
Biomarcadores de Tumor , Glioblastoma/etiología , Medicina de Precisión , Ensayos Clínicos Fase I como Asunto , Receptores ErbB/genética , Receptores ErbB/metabolismo , Amplificación de Genes , Perfilación de la Expresión Génica , Pruebas Genéticas , Glioblastoma/diagnóstico , Glioblastoma/metabolismo , Glioblastoma/terapia , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Medicina de Precisión/métodos , Medicina de Precisión/normas , Reacción en Cadena en Tiempo Real de la Polimerasa , Secuenciación del Exoma
18.
Brain Res ; 1233: 203-13, 2008 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-18675258

RESUMEN

Cell therapy is prospective, modern attempt to ischemic stroke treatment. It has been being widely worked out recently. We suggest mesenchymal stem cells (MSC) as a cell therapy agent in the therapy of this disease. Experiments were carried out in inbred male Wistar-Kyoto rats. Animals were subjected to middle cerebral artery occlusion (MCAO). MSCs were isolated from rat bone marrow, expanded in culture and labelled with vital fluorescent dye PKH-26. Then 5 x 10(6) cells were injected into the tail vein on the day of MCAO and three days later. Control group animals received PBS injection (negative control). Cognitive function restoration was estimated by Morris Water Maze testing during 6 weeks after MCAO. Animals were sacrificed 1, 2, 3, 5 days and 1, 2, 4 and 6 weeks after operation. Intravenous MSC transplantation decreased post-operation mortality and benefited behavioural and neurological recovery. Experimental groups animals revealed changes in aseptic inflammation processes which were completed faster comparing to control group. That effect correlated with accelerated glial scar formation. Reduction of the infarct volumes and such post-stroke after-effects as border zone gliosis and liquor cysts formation accompanied by increased angiogenesis and subventricular zone cells proliferation were shown after cell therapy. The obtained results referred to both cell therapy groups. Thus, MSC injection benefited post-stroke rehabilitation irrespective of transplantation time. However, further investigation should be carried out in order to find out the mechanism of their action.


Asunto(s)
Isquemia Encefálica/terapia , Encéfalo/citología , Aprendizaje por Laberinto/fisiología , Trasplante de Células Madre Mesenquimatosas , Accidente Cerebrovascular/terapia , Animales , Encéfalo/patología , Encéfalo/fisiología , Isquemia Encefálica/etiología , Isquemia Encefálica/patología , Estudios de Seguimiento , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/patología , Masculino , Células Madre Mesenquimatosas/citología , Ratas , Ratas Endogámicas WKY , Recuperación de la Función , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/patología
19.
Materials (Basel) ; 11(8)2018 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-30111700

RESUMEN

The high dielectric constant ferroelectric-polymer nanocomposite was developed for producing the heat-resistant and chemical stable planar layers. According to the composite coatings formation conditions, the following value ranges of dielectric constant and loss factor were received: 30⁻400 for dielectric constant and 0.04⁻0.1 for loss tangent, accordingly. Unlike of composite components, the obtained composite material is characterized by thermo-stability of electrical parameters up to 250 °C. The dielectric frequency spectra of the composite exhibit two clearly visible peaks in contrast to the spectra of the polymer and ferroelectric ceramics. The developed composite material can be used as a built-in film capacitors material in microelectronic devices.

20.
J Mol Diagn ; 9(5): 604-11, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17975027

RESUMEN

The goal of this study was to compare how accumulation of chromosomal aberrations in human papillomavirus (HPV)-infected cells correlates with the severity of cervical dysplastic lesions. We assessed the frequency of genomic alterations for 35 different loci in a pilot biopsy study and selected two loci (3q26 and 8q24) with the highest frequency of copy number gains found in high-grade dysplasia and cancer. These probes were labeled with gold and red fluorophores and combined with HPV biotin-labeled probes for subsequent detection using a tyramide signal amplification system with a green fluorophore. Cells that were both HPV positive and chromosomally abnormal were designated as "double-positive cells." Cervical cytology specimens from 235 patients were used for this blinded study. The average number of double-positive cells increased from two cells in patients with a cytological interpretation of atypical squamous cells of undetermined significance to 22 cells in low-grade squamous intraepithelial lesion and 99 cells in high-grade squamous intraepithelial lesion, reflecting an accumulation of chromosomal abnormality with disease progression. Using a cutoff of four or more double-positive cells as the criterion for the presence of a cervical intraepithelial neoplasia 2 or 3 lesion, we demonstrated that low-grade squamous intraepithelial lesion and high-grade squamous intraepithelial lesion cytology specimens with underlying cervical intraepithelial neoplasia 2/3 histology showed positive test results in more than 80% of cases. Correlation of 3q26 and 8q24 aneusomy with concurrent HPV infection may thus serve as a biomarker of genetic instability in HPV-infected cells.


Asunto(s)
Alphapapillomavirus/fisiología , Cromosomas Humanos/genética , Células Epiteliales/metabolismo , Células Epiteliales/virología , Inestabilidad Genómica , Frotis Vaginal , Aberraciones Cromosómicas , Cromosomas Humanos Par 3 , Cromosomas Humanos Par 8 , Femenino , Dosificación de Gen , Marcadores Genéticos , Humanos
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