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1.
J Virol ; 94(8)2020 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-32024773

RESUMEN

Optimization of immunogen is crucial for induction of effective T-cell responses in the development of a human immunodeficiency virus (HIV) vaccine. Conventional T-cell-based vaccines have been designed to induce virus-specific CD4+ T as well as CD8+ T cells. However, it has been indicated that induction of HIV-specific CD4+ T cells, preferential targets for HIV infection, by vaccination may be detrimental and accelerate viral replication after HIV exposure. In the present study, we present a novel immunogen to selectively induce CD8+ T cells but not CD4+ T cells targeting viral antigens. The immunogen, CaV11, was constructed by tandem connection of overlapping 11-mer peptides spanning simian immunodeficiency virus (SIV) Gag capsid (CA) and Vif. Prime-boost immunization with DNA and Sendai virus (SeV) vectors expressing CaV11 efficiently induced Gag/Vif-specific CD8+ T-cell responses with inefficient Gag/Vif-specific CD4+ T-cell induction in rhesus macaques (n = 6). None of the macaques exhibited the enhancement of acute viral replication after an intravenous high-dose SIV challenge, which was observed in those immunized with DNA and SeV expressing the whole Gag protein in our previous study. Set point viral control postinfection was associated with SeV-specific CD4+ T-cell responses postimmunization, suggesting contribution of SeV-specific helper responses to effective Gag/Vif-specific CD8+ T-cell induction by vaccination. This immunogen design could be a promising method for selective induction of effective anti-HIV CD8+ T-cell responses.IMPORTANCE Induction of effective CD8+ T-cell responses is an important HIV vaccine strategy. Several promising vaccine delivery tools have been developed, and immunogen optimization is now crucial for effective T-cell induction. Conventional immunogens have been designed to induce virus-specific CD4+ T cells as well as CD8+ T cells, but induction of virus-specific CD4+ T cells that are preferential targets for HIV infection could enhance acute HIV proliferation. Here, we designed a novel immunogen to induce HIV-specific CD8+ T cells without HIV-specific CD4+ T-cell induction but with non-HIV antigen-specific CD4+ T-cell help. Our analysis in a macaque AIDS model showed that our immunogen can efficiently elicit effective CD8+ T but not CD4+ T cells targeting viral antigens, resulting in no enhancement of acute viral replication after virus exposure. This immunogen design, also applicable for other currently developed immunogens, could be a promising method for selective induction of effective anti-HIV CD8+ T-cell responses.


Asunto(s)
Antígenos Virales/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/inmunología , Vacunas contra el SIDA/inmunología , Secuencia de Aminoácidos , Animales , Modelos Animales de Enfermedad , Inmunización , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Virus de la Inmunodeficiencia de los Simios/inmunología , Vacunación , Carga Viral , Replicación Viral , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/inmunología , Productos del Gen vif del Virus de la Inmunodeficiencia Humana/inmunología
2.
Brain ; 143(6): 1811-1825, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32436573

RESUMEN

The polyglutamine (polyQ) diseases are a group of inherited neurodegenerative diseases that include Huntington's disease, various spinocerebellar ataxias, spinal and bulbar muscular atrophy, and dentatorubral pallidoluysian atrophy. They are caused by the abnormal expansion of a CAG repeat coding for the polyQ stretch in the causative gene of each disease. The expanded polyQ stretches trigger abnormal ß-sheet conformational transition and oligomerization followed by aggregation of the polyQ proteins in the affected neurons, leading to neuronal toxicity and neurodegeneration. Disease-modifying therapies that attenuate both symptoms and molecular pathogenesis of polyQ diseases remain an unmet clinical need. Here we identified arginine, a chemical chaperone that facilitates proper protein folding, as a novel compound that targets the upstream processes of polyQ protein aggregation by stabilizing the polyQ protein conformation. We first screened representative chemical chaperones using an in vitro polyQ aggregation assay, and identified arginine as a potent polyQ aggregation inhibitor. Our in vitro and cellular assays revealed that arginine exerts its anti-aggregation property by inhibiting the toxic ß-sheet conformational transition and oligomerization of polyQ proteins before the formation of insoluble aggregates. Arginine exhibited therapeutic effects on neurological symptoms and protein aggregation pathology in Caenorhabditis elegans, Drosophila, and two different mouse models of polyQ diseases. Arginine was also effective in a polyQ mouse model when administered after symptom onset. As arginine has been safely used for urea cycle defects and for mitochondrial myopathy, encephalopathy, lactic acid and stroke syndrome patients, and efficiently crosses the blood-brain barrier, a drug-repositioning approach for arginine would enable prompt clinical application as a promising disease-modifier drug for the polyQ diseases.


Asunto(s)
Arginina/metabolismo , Arginina/farmacología , Péptidos/metabolismo , Animales , Caenorhabditis elegans/metabolismo , Modelos Animales de Enfermedad , Drosophila/metabolismo , Femenino , Trastornos Heredodegenerativos del Sistema Nervioso/genética , Enfermedad de Huntington/genética , Masculino , Ratones , Ratones Endogámicos , Chaperonas Moleculares/genética , Péptidos/genética , Agregación Patológica de Proteínas , Conformación Proteica/efectos de los fármacos , Pliegue de Proteína/efectos de los fármacos , Ataxias Espinocerebelosas/genética
3.
Neural Comput ; 32(8): 1580-1613, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32521217

RESUMEN

We propose a new formulation of multiple-instance learning (MIL), in which a unit of data consists of a set of instances called a bag. The goal is to find a good classifier of bags based on the similarity with a "shapelet" (or pattern), where the similarity of a bag with a shapelet is the maximum similarity of instances in the bag. In previous work, some of the training instances have been chosen as shapelets with no theoretical justification. In our formulation, we use all possible, and thus infinitely many, shapelets, resulting in a richer class of classifiers. We show that the formulation is tractable, that is, it can be reduced through linear programming boosting (LPBoost) to difference of convex (DC) programs of finite (actually polynomial) size. Our theoretical result also gives justification to the heuristics of some previous work. The time complexity of the proposed algorithm highly depends on the size of the set of all instances in the training sample. To apply to the data containing a large number of instances, we also propose a heuristic option of the algorithm without the loss of the theoretical guarantee. Our empirical study demonstrates that our algorithm uniformly works for shapelet learning tasks on time-series classification and various MIL tasks with comparable accuracy to the existing methods. Moreover, we show that the proposed heuristics allow us to achieve the result in reasonable computational time.

4.
Glia ; 66(11): 2366-2384, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30375063

RESUMEN

Excitotoxicity is well known in the neuronal death in the brain and is also linked to neuronal damages in the retina. Recent accumulating evidence show that microglia greatly affect excitotoxicity in the brain, but their roles in retina have received only limited attention. Here, we report that retinal excitotoxicity is mediated by microglia. To this end, we employed three discrete methods, that is, pharmacological inhibition of microglia by minocycline, pharmacological ablation by an antagonist for colony stimulating factor 1 receptor (PLX5622), and genetic ablation of microglia using Iba1-tTA::DTAtetO/tetO mice. Intravitreal injection of NMDA increased the number of apoptotic retinal ganglion cells (RGCs) followed by reduction in the number of RGCs. Although microglia did not respond to NMDA directly, they became reactive earlier than RGC damages. Inhibition or ablation of microglia protected RGCs against NMDA. We found up-regulation of proinflammatory cytokine genes including Il1b, Il6 and Tnfa, among which Tnfa was selectively blocked by minocycline. PLX5622 also suppressed Tnfa expression. Tumor necrosis factor α (TNFα) signals were restricted in microglia at very early followed by spreading into other cell types. TNFα up-regulation in microglia and other cells were significantly attenuated by minocycline and PLX5622, suggesting a central role of microglia for TNFα induction. Both inhibition of TNFα and knockdown of TNF receptor type 1 by siRNA protected RGCs against NMDA. Taken together, our data demonstrate that a phenotypic change of microglia into a neurotoxic one is a critical event for the NMDA-induced degeneration of RGCs, suggesting an importance of non-cell-autonomous mechanism in the retinal neuronal excitotoxicity.


Asunto(s)
Muerte Celular/fisiología , Citocinas/metabolismo , Microglía/fisiología , Células Ganglionares de la Retina/fisiología , Aminopiridinas/farmacología , Animales , Animales Recién Nacidos , Proteínas de Unión al Calcio/genética , Proteínas de Unión al Calcio/metabolismo , Muerte Celular/efectos de los fármacos , Células Cultivadas , Citocinas/genética , Agonistas de Aminoácidos Excitadores/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Microglía/efectos de los fármacos , Microglía/ultraestructura , N-Metilaspartato/farmacología , Degeneración Nerviosa/inducido químicamente , Traumatismos del Nervio Óptico/inducido químicamente , Compuestos Orgánicos/farmacología , Pirroles/farmacología , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/ultraestructura , Transducción de Señal/efectos de los fármacos , Factor de Transcripción Brn-3A/genética , Factor de Transcripción Brn-3A/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
5.
Neural Comput ; 29(5): 1406-1438, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28333592

RESUMEN

Nonconvex variants of support vector machines (SVMs) have been developed for various purposes. For example, robust SVMs attain robustness to outliers by using a nonconvex loss function, while extended [Formula: see text]-SVM (E[Formula: see text]-SVM) extends the range of the hyperparameter by introducing a nonconvex constraint. Here, we consider an extended robust support vector machine (ER-SVM), a robust variant of E[Formula: see text]-SVM. ER-SVM combines two types of nonconvexity from robust SVMs and E[Formula: see text]-SVM. Because of the two nonconvexities, the existing algorithm we proposed needs to be divided into two parts depending on whether the hyperparameter value is in the extended range or not. The algorithm also heuristically solves the nonconvex problem in the extended range. In this letter, we propose a new, efficient algorithm for ER-SVM. The algorithm deals with two types of nonconvexity while never entailing more computations than either E[Formula: see text]-SVM or robust SVM, and it finds a critical point of ER-SVM. Furthermore, we show that ER-SVM includes the existing robust SVMs as special cases. Numerical experiments confirm the effectiveness of integrating the two nonconvexities.

6.
Neuro Endocrinol Lett ; 38(3): 163-168, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28759183

RESUMEN

OBJECTIVES: Several studies indicate that cyclosporin A has a protective effect against brain infarction. In this study, we aimed to determine if co-administration of cyclosporin A and ondansetron could reduce damage caused by cerebral ischemia. METHODS: ICR (Charles River Laboratories) mice were subjected to transient focal cerebral ischemia and divided into 4 groups (O, V, C, and Mix). Immediately after reperfusion, each ligand was administered intravenously through the external jugular vein. Group V animals received 0.9% saline alone, group O animals received 0.1 mg/kg ondansetron solution, group C animals received 10 mg/kg cyclosporin A solution, and group Mix received 0.1 mg/kg ondansetron solution and 10 mg/kg cyclosporin A solution. RESULTS: Our results showed that the volume of brain infarction induced by middle cerebral artery occlusion in group Mix was significantly smaller than that seen in group V. Forty-eight hours after ischemia, the neurological scores of rats from group Mix significantly improved when compared to group V. CONCLUSION: Overall, our study showed that a combination of cyclosporin A and ondansetron may be a practical clinical method to treat brain infarction. However, further studies are required to investigate the cerebroprotective mechanism of action, the possible side effects of co-administration of these drugs, and the ability of these ligands to cross the blood brain barrier.


Asunto(s)
Ciclosporina/uso terapéutico , Ataque Isquémico Transitorio/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Ondansetrón/uso terapéutico , Animales , Circulación Cerebrovascular/efectos de los fármacos , Ciclosporina/farmacología , Modelos Animales de Enfermedad , Quimioterapia Combinada , Masculino , Ratones , Ratones Endogámicos ICR , Fármacos Neuroprotectores/farmacología , Ondansetrón/farmacología , Resultado del Tratamiento
7.
Bioinformatics ; 31(15): 2530-6, 2015 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25819671

RESUMEN

BACKGROUND: In high-throughput experimental biology, it is widely acknowledged that while expression levels measured at the levels of transcriptome and the corresponding proteome do not, in general, correlate well, messenger RNA levels are used as convenient proxies for protein levels. Our interest is in developing data-driven computational models that can bridge the gap between these two levels of measurement at which different mechanisms of regulation may act on different molecular species causing any observed lack of correlations. To this end, we build data-driven predictors of protein levels using mRNA levels and known proxies of translation efficiencies as covariates. Previous work showed that in such a setting, outliers with respect to the model are reliable candidates for post-translational regulation. RESULTS: Here, we present and compare two novel formulations of deriving a protein concentration predictor from which outliers may be extracted in a systematic manner. The first approach, outlier rejecting regression, allows explicit specification of a certain fraction of the data as outliers. In a regression setting, this is a non-convex optimization problem which we solve by deriving a difference of convex functions algorithm (DCA). With post-translationally regulated proteins, one expects their concentrations to be affected primarily by disruption of protein stability. Our second algorithm exploits this observation by minimizing an asymmetric loss using quantile regression and extracts outlier proteins whose measured concentrations are lower than what a genome-wide regression would predict. We validate the two approaches on a dataset of yeast transcriptome and proteome. Functional annotation check on detected outliers demonstrate that the methods are able to identify post-translationally regulated genes with high statistical confidence.


Asunto(s)
Biología Computacional/métodos , Proteoma/metabolismo , ARN Mensajero/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Transcriptoma , Algoritmos , Biomarcadores/análisis , Regulación Fúngica de la Expresión Génica , Genoma Fúngico , Saccharomyces cerevisiae/metabolismo
8.
Semin Cancer Biol ; 27: 3-10, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24657637

RESUMEN

Hematologic malignancies are often associated with chromosomal rearrangements that lead to the expression of chimeric fusion proteins. Rearrangements of the genes encoding two nucleoporins, NUP98 and NUP214, have been implicated in the pathogenesis of several types of hematologic malignancies, particularly acute myeloid leukemia. NUP98 rearrangements result in fusion of an N-terminal portion of NUP98 to one of numerous proteins. These rearrangements often follow treatment with topoisomerase II inhibitors and tend to occur in younger patients. They have been shown to induce leukemia in mice and to enhance proliferation and disrupt differentiation in primary human hematopoietic precursors. NUP214 has only a few fusion partners. DEK-NUP214 is the most common NUP214 fusion in AML; it tends to occur in younger patients and is usually associated with FLT3 internal tandem duplications. The leukemogenic activity of NUP214 fusions is less well characterized. Normal nucleoporins, including NUP98 and NUP214, have important functions in nucleocytoplasmic transport, transcription, and mitosis. These functions and their disruptions by oncogenic nucleoporin fusions are discussed.


Asunto(s)
Neoplasias Hematológicas/metabolismo , Proteínas de Complejo Poro Nuclear/metabolismo , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Neoplasias Hematológicas/genética , Humanos , Mitosis , Transcripción Genética
9.
J Virol ; 88(24): 14232-40, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25275131

RESUMEN

UNLABELLED: CD4(+) T-cell responses are crucial for effective antibody and CD8(+) T-cell induction following virus infection. However, virus-specific CD4(+) T cells can be preferential targets for human immunodeficiency virus (HIV) infection. HIV-specific CD4(+) T-cell induction by vaccination may thus result in enhancement of virus replication following infection. In the present study, we show that vaccine-elicited CD4(+) T cells expressing CD107a are relatively resistant to depletion in a macaque AIDS model. Comparison of virus-specific CD107a, macrophage inflammatory protein-1ß, gamma interferon, tumor necrosis factor alpha, and interleukin-2 responses in CD4(+) T cells of vaccinated macaques prechallenge and 1 week postchallenge showed a significant reduction in the CD107a(-) but not the CD107a(+) subset after virus exposure. Those vaccinees that failed to control viremia showed a more marked reduction and exhibited significantly higher viral loads at week 1 than unvaccinated animals. Our results indicate that vaccine-induced CD107a(-) CD4(+) T cells are depleted following virus infection, suggesting a rationale for avoiding virus-specific CD107a(-) CD4(+) T-cell induction in HIV vaccine design. IMPORTANCE: Induction of effective antibody and/or CD8(+) T-cell responses is a principal vaccine strategy against human immunodeficiency virus (HIV) infection. CD4(+) T-cell responses are crucial for effective antibody and CD8(+) T-cell induction. However, virus-specific CD4(+) T cells can be preferential targets for HIV infection. Here, we show that vaccine-induced virus-specific CD107a(-) CD4(+) T cells are largely depleted following infection in a macaque AIDS model. While CD4(+) T-cell responses are important in viral control, our results indicate that virus-specific CD107a(-) CD4(+) T-cell induction by vaccination may not lead to efficient CD4(+) T-cell responses following infection but rather be detrimental and accelerate viral replication in the acute phase. This suggests that HIV vaccine design should avoid virus-specific CD107a(-) CD4(+) T-cell induction. Conversely, this study found that vaccine-induced CD107a(+) CD4(+) T cells are relatively resistant to depletion following virus challenge, implying that induction of these cells may be an alternative approach toward HIV control.


Asunto(s)
Vacunas contra el SIDA/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/virología , VIH/crecimiento & desarrollo , Subgrupos Linfocitarios/inmunología , Subgrupos Linfocitarios/virología , Proteína 1 de la Membrana Asociada a los Lisosomas/análisis , Vacunas contra el SIDA/administración & dosificación , Animales , Recuento de Linfocito CD4 , Linfocitos T CD4-Positivos/química , Subgrupos Linfocitarios/química , Macaca mulatta
10.
Neural Comput ; 26(11): 2541-69, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25058701

RESUMEN

Financial risk measures have been used recently in machine learning. For example, ν-support vector machine ν-SVM) minimizes the conditional value at risk (CVaR) of margin distribution. The measure is popular in finance because of the subadditivity property, but it is very sensitive to a few outliers in the tail of the distribution. We propose a new classification method, extended robust SVM (ER-SVM), which minimizes an intermediate risk measure between the CVaR and value at risk (VaR) by expecting that the resulting model becomes less sensitive than ν-SVM to outliers. We can regard ER-SVM as an extension of robust SVM, which uses a truncated hinge loss. Numerical experiments imply the ER-SVM's possibility of achieving a better prediction performance with proper parameter setting.


Asunto(s)
Inteligencia Artificial , Modelos Teóricos , Conducta de Reducción del Riesgo , Máquina de Vectores de Soporte , Algoritmos , Administración Financiera , Humanos
11.
Acta Med Okayama ; 68(2): 119-23, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24743787

RESUMEN

Acute megakaryocytic leukemia (AMKL) with t(1;22)(p13;q13) is a distinct category of myeloid leukemia by WHO classification and mainly reported in infants and young children. Accurate diagnosis of this type of AMKL can be difficult, because a subset of patients have a bone marrow (BM) blast percentage of less than 20% due to BM fibrosis. Therefore, it is possible that past studies have underestimated this type of AMKL. We present here the case of a 4-month-old female AMKL patient who was diagnosed by presence of the RBM15-MKL1 (OTT-MAL) fusion transcript by RT-PCR. In addition, we monitored RBM15-MKL1 fusion at several time points as a marker of minimal residual disease (MRD), and found that it was continuously negative after the first induction chemotherapy even by nested RT-PCR. Detection of the RBM15-MKL1 fusion transcript thus seems to be useful for accurate diagnosis of AMKL with t(1;22)(p13;q13). We recommend that the RBM15-MKL1 fusion transcript be analyzed for all suspected AMKL in infants and young children. Furthermore, monitoring of MRD using this fusion transcript would be useful in treatment of AMKL with t(1;22)(p13;q13).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Monitoreo de Drogas/métodos , Leucemia Megacarioblástica Aguda/tratamiento farmacológico , Leucemia Megacarioblástica Aguda/genética , Proteínas de Fusión Oncogénica/genética , Femenino , Humanos , Lactante , Neoplasia Residual/tratamiento farmacológico , Neoplasia Residual/genética , Reacción en Cadena de la Polimerasa/métodos
12.
J Virol ; 86(2): 738-45, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22072784

RESUMEN

Cytotoxic T lymphocyte (CTL) responses play a central role in viral suppression in human immunodeficiency virus (HIV) infections. Prophylactic vaccination resulting in effective CTL responses after viral exposure would contribute to HIV control. It is important to know how CTL memory induction by vaccination affects postexposure CTL responses. We previously showed vaccine-based control of a simian immunodeficiency virus (SIV) challenge in a group of Burmese rhesus macaques sharing a major histocompatibility complex class I haplotype. Gag(206-216) and Gag(241-249) epitope-specific CTL responses were responsible for this control. In the present study, we show the impact of individual epitope-specific CTL induction by prophylactic vaccination on postexposure CTL responses. In the acute phase after SIV challenge, dominant Gag(206-216)-specific CTL responses with delayed, naive-derived Gag(241-249)-specific CTL induction were observed in Gag(206-216) epitope-vaccinated animals with prophylactic induction of single Gag(206-216) epitope-specific CTL memory, and vice versa in Gag(241-249) epitope-vaccinated animals with single Gag(241-249) epitope-specific CTL induction. Animals with Gag(206-216)-specific CTL induction by vaccination selected for a Gag(206-216)-specific CTL escape mutation by week 5 and showed significantly less decline of plasma viral loads from week 3 to week 5 than in Gag(241-249) epitope-vaccinated animals without escape mutations. Our results present evidence indicating significant influence of prophylactic vaccination on postexposure CTL immunodominance and cooperation of vaccine antigen-specific and non-vaccine antigen-specific CTL responses, which affects virus control. These findings provide great insights into antigen design for CTL-inducing AIDS vaccines.


Asunto(s)
Vacunas contra el SIDAS/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/fisiología , Linfocitos T Citotóxicos/inmunología , Replicación Viral , Animales , Modelos Animales de Enfermedad , Epítopos de Linfocito T/genética , Epítopos de Linfocito T/inmunología , VIH/genética , VIH/inmunología , VIH/fisiología , Infecciones por VIH/inmunología , Infecciones por VIH/prevención & control , Infecciones por VIH/virología , Humanos , Macaca mulatta , Vacunas contra el SIDAS/administración & dosificación , Vacunas contra el SIDAS/genética , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/inmunología , Linfocitos T Citotóxicos/virología , Vacunación , Carga Viral
13.
J Virol ; 86(12): 6481-90, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22491464

RESUMEN

Nonhuman primate AIDS models are essential for the analysis of AIDS pathogenesis and the evaluation of vaccine efficacy. Multiple studies on human immunodeficiency virus and simian immunodeficiency virus (SIV) infection have indicated the association of major histocompatibility complex class I (MHC-I) genotypes with rapid or slow AIDS progression. The accumulation of macaque groups that share not only a single MHC-I allele but also an MHC-I haplotype consisting of multiple polymorphic MHC-I loci would greatly contribute to the progress of AIDS research. Here, we investigated SIVmac239 infections in four groups of Burmese rhesus macaques sharing individual MHC-I haplotypes, referred to as A, E, B, and J. Out of 20 macaques belonging to A(+) (n = 6), E(+) (n = 6), B(+) (n = 4), and J(+) (n = 4) groups, 18 showed persistent viremia. Fifteen of them developed AIDS in 0.5 to 4 years, with the remaining three at 1 or 2 years under observation. A(+) animals, including two controllers, showed slower disease progression, whereas J(+) animals exhibited rapid progression. E(+) and B(+) animals showed intermediate plasma viral loads and survival periods. Gag-specific CD8(+) T-cell responses were efficiently induced in A(+) animals, while Nef-specific CD8(+) T-cell responses were in A(+), E(+), and B(+) animals. Multiple comparisons among these groups revealed significant differences in survival periods, peripheral CD4(+) T-cell decline, and SIV-specific CD4(+) T-cell polyfunctionality in the chronic phase. This study indicates the association of MHC-I haplotypes with AIDS progression and presents an AIDS model facilitating the analysis of virus-host immune interaction.


Asunto(s)
Infecciones por VIH/genética , Infecciones por VIH/patología , Antígenos de Histocompatibilidad Clase I/genética , Síndrome de Inmunodeficiencia Adquirida del Simio/genética , Síndrome de Inmunodeficiencia Adquirida del Simio/patología , Virus de la Inmunodeficiencia de los Simios/fisiología , Alelos , Animales , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/genética , VIH-1/inmunología , Haplotipos , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Macaca mulatta , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/genética , Virus de la Inmunodeficiencia de los Simios/inmunología
14.
Neural Comput ; 25(3): 759-804, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23272917

RESUMEN

A wide variety of machine learning algorithms such as the support vector machine (SVM), minimax probability machine (MPM), and Fisher discriminant analysis (FDA) exist for binary classification. The purpose of this letter is to provide a unified classification model that includes these models through a robust optimization approach. This unified model has several benefits. One is that the extensions and improvements intended for SVMs become applicable to MPM and FDA, and vice versa. For example, we can obtain nonconvex variants of MPM and FDA by mimicking Perez-Cruz, Weston, Hermann, and Schölkopf's (2003) extension from convex ν-SVM to nonconvex Eν-SVM. Another benefit is to provide theoretical results concerning these learning methods at once by dealing with the unified model. We give a statistical interpretation of the unified classification model and prove that the model is a good approximation for the worst-case minimization of an expected loss with respect to the uncertain probability distribution. We also propose a nonconvex optimization algorithm that can be applied to nonconvex variants of existing learning methods and show promising numerical results.


Asunto(s)
Máquina de Vectores de Soporte
15.
Acta Neurochir Suppl ; 118: 307-10, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23564155

RESUMEN

BACKGROUND: Although protein kinase C-γ (PKC-γ) is a target for the effects of volatile anesthetics, the molecular mechanisms of the kinase function remain unclear. We examined the effects of different types of anesthetics on PKC-γ knockout mice, and investigated the dynamics of the kinase in mouse brain. METHODS: We measured the required number of times for loss of righting reflex (rtfLORR) after administration of isoflurane, sevoflurane, and propofol on PKC-γ knockout mice and compared with those of wild-type mice. We also used immunoblotting to investigate the intracellular distribution of PKC-γ and phosphorylated PKC-γ (p-PKC-γ) in brain of wild-type mice anesthetized by these anesthetics. RESULTS: Isoflurane and sevoflurane significantly prolonged the rtfLORRs in PKC-γ knockout mice compared with those in wild-type mice, while no significant difference was observed between knockout and wild-type mice treated with propofol. Examination of the cellular fractions showed that PKC-γ was significantly decreased, whereas p-PKC-γ was significantly increased in the synaptic membrane fraction (P2). There was no significant change in the supernatant fraction (S). In propofol-treated mice, PKC-γ and p-PKC-γ showed no significant changes in P2 or S. CONCLUSION: Our results provide new evidence to support the possibility of the involvement of PKC-γ in the actions of volatile anesthetics.


Asunto(s)
Anestésicos por Inhalación/administración & dosificación , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Reflejo de Enderezamiento/efectos de los fármacos , Animales , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación/efectos de los fármacos , Fosforilación/genética , Proteína Quinasa C/deficiencia , Reflejo de Enderezamiento/genética , Factores de Tiempo
16.
Masui ; 62(12): 1419-21, 2013 Dec.
Artículo en Japonés | MEDLINE | ID: mdl-24498773

RESUMEN

First and second branchial arch syndrome is a congenital anomaly of craniofacial dysplasia involving organs derived from the second branchial arch. The main characteristics are microtia and mandibular hypoplasia. A 6-year-old boy was scheduled for adenoidectomy and bilateral myringotomy and tube placement. Slow induction was performed with oxygen, nitrous oxide, and sevoflurane. No difficulties were encountered during mask ventilation, and rocuronium was administered intravenously. His epiglottis was not visible during laryngoscopy. Therefore, we used the Airwayscope (AWS). His glottis was visible after application of cricold pressure from the left side. However, we could not closely conform his epiglottis to the mark on the AWS. Therefore, we passed a fiberoptic bronchoscope through a tracheal tube and placed it in the AWS. We attempted to intubate the trachea, but could not guide the bronchoscope to his glottis. We then attempted to pull the tracheal tube to improve the mobility of the bronchoscope. Control of the bronchoscope consequently became easy We successfully guided it to his glottis and performed tracheal intubation. His condition was stable during the procedure. In conclusion, we safely performed tracheal intubation in a patient with first and second branchial arch syndrome using the AWS and a fiberoptic bronchoscope.


Asunto(s)
Región Branquial/anomalías , Oído/anomalías , Enfermedades Genéticas Ligadas al Cromosoma X/cirugía , Pérdida Auditiva/cirugía , Intubación Intratraqueal/instrumentación , Intubación Intratraqueal/métodos , Laringoscopios , Disostosis Mandibulofacial/cirugía , Microcefalia/cirugía , Cuello/anomalías , Adenoidectomía , Anestesia , Región Branquial/cirugía , Broncoscopios , Niño , Oído/cirugía , Humanos , Masculino , Ventilación del Oído Medio , Cuello/cirugía , Fibras Ópticas
17.
PLoS One ; 18(10): e0291305, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37792698

RESUMEN

A substantial body of evidence points to the heritability of dietary preferences. While vegetarianism has been practiced for millennia in various societies, its practitioners remain a small minority of people worldwide, and the role of genetics in choosing a vegetarian diet is not well understood. Dietary choices involve an interplay between the physiologic effects of dietary items, their metabolism, and taste perception, all of which are strongly influenced by genetics. In this study, we used a genome-wide association study (GWAS) to identify loci associated with strict vegetarianism in UK Biobank participants. Comparing 5,324 strict vegetarians to 329,455 controls, we identified one SNP on chromosome 18 that is associated with vegetarianism at the genome-wide significant level (rs72884519, ß = -0.11, P = 4.997 x 10-8), and an additional 201 suggestively significant variants. Four genes are associated with rs72884519: TMEM241, RIOK3, NPC1, and RMC1. Using the Functional Mapping and Annotation (FUMA) platform and the Multi-marker Analysis of GenoMic Annotation (MAGMA) tool, we identified 34 genes with a possible role in vegetarianism, 3 of which are GWAS-significant based on gene-level analysis: RIOK3, RMC1, and NPC1. Several of the genes associated with vegetarianism, including TMEM241, NPC1, and RMC1, have important functions in lipid metabolism and brain function, raising the possibility that differences in lipid metabolism and their effects on the brain may underlie the ability to subsist on a vegetarian diet. These results support a role for genetics in choosing a vegetarian diet and open the door to future studies aimed at further elucidating the physiologic pathways involved in vegetarianism.


Asunto(s)
Dieta Vegetariana , Estudio de Asociación del Genoma Completo , Humanos , Dieta , Dieta Vegana , Encéfalo
18.
Mol Ther Nucleic Acids ; 31: 353-366, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36817728

RESUMEN

The abnormal aggregation of TDP-43 into cytoplasmic inclusions in affected neurons is a pathological hallmark of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Although how TDP-43 forms cytoplasmic aggregates and causes neurodegeneration in patients with ALS/FTD remains unclear, reducing cellular TDP-43 levels is likely to prevent aggregation and to rescue neurons from TDP-43 toxicity. To address this issue, here we developed gapmer-type antisense oligonucleotides (ASOs) against human TDP-43 using 2'-O,4'-C-ethylene nucleic acids (ENAs), which are modified nucleic acids with high stability, and tested the therapeutic potential of lowering TDP-43 levels using ENA-modified ASOs. We demonstrated that intracerebroventricular administration of ENA-modified ASOs into a mouse model of ALS/FTD expressing human TDP-43 results in the efficient reduction of TDP-43 levels in the brain and spinal cord. Surprisingly, a single injection of ENA-modified ASOs into TDP-43 mice led to long-lasting improvement of behavioral abnormalities and the suppression of cytoplasmic TDP-43 aggregation, even after TDP-43 levels had returned to the initial levels. Our results demonstrate that transient reduction of TDP-43 using ENA-modified ASOs leads to sustained therapeutic benefits in vivo, indicating the possibility of a disease-modifying therapy by lowering TDP-43 levels for the treatment of the TDP-43 proteinopathies, including ALS/FTD.

19.
Masui ; 61(8): 855-8, 2012 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-22991811

RESUMEN

Neuromuscular blocking drugs (NMBDs) can predispose patients with myasthenia gravis to postoperative paralysis and respiratory complications. We had a 12-year-old female patient undergoing thoracoscopic thymectomy. She had suffered from MGFA class IIa (mild systemic) myasthenia gravis for 4 months. Anesthesia was induced with 3 mg x kg(-1) of thiopental and 0.2 mg x kg(-1) of rocuronium, which was given incrementally to achieve 100% blockade. Anesthesia was maintained with oxygen, air, 2% sevoflurane and 0.2 microg x kg(-1) x min(-1) of remifentanil. 0.05 mg x kg(-1) of rocuronium was added when the TOF ratio recovered to 20%. Towards the end of the surgery, remifentanil was withdrawn and 4 microg x kg(-1) of fentanyl was given. Intercostal nerve block with 0.2% ropivacaine was performed to relieve postoperative pain. TOF ratio was 32% at the end, when we gave 2 mg x kg(-1) of sugammadex to get 100% reversal of neuromuscular blockade in 120 seconds. There was no residual paralysis and respiratory complications postoperatively.


Asunto(s)
Androstanoles/administración & dosificación , Androstanoles/antagonistas & inhibidores , Anestesia General , Miastenia Gravis/cirugía , Bloqueo Neuromuscular , Fármacos Neuromusculares no Despolarizantes/antagonistas & inhibidores , Atención Perioperativa , Toracoscopía , Timectomía , gamma-Ciclodextrinas/administración & dosificación , gamma-Ciclodextrinas/farmacología , Niño , Femenino , Humanos , Rocuronio , Índice de Severidad de la Enfermedad , Sugammadex
20.
Cureus ; 14(5): e24869, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35547945

RESUMEN

The reported case is of a 68-year-old man who was admitted to the ICU at our tertiary care medical center with severe COVID-19. He was admitted to the ICU due to a worsening respiratory condition during his hospitalization at the same medical center, which included the development of severe acute respiratory distress syndrome (ARDS). Ventilator management was started with alveolar protection in mind. On the ninth day of ventilator management, we judged that it was necessary to introduce extracorporeal membrane oxygenation (ECMO). Although the ninth day of ventilator management is considered relatively late for starting ECMO, there are no absolute contraindications for ECMO at this stage, and improvements in oxygenation can be expected. After introducing ECMO, the patient's oxygenation capacity improved, and ECMO was successfully withdrawn within 16 days. The patient required long-term rehabilitation but was discharged from the hospital to his home without lingering disease complications on the 150th day of illness and subsequently resumed his former work, daily activities, and quality of life. We conclude that, in regard to the introduction of ECMO for ARDS, it is necessary to reach a comprehensive judgment without being bound by any one index (such as the ventilation management period prior to ECMO introduction).

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