Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Glycobiology ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39088577

RESUMEN

The prevalent human pathogen, mumps virus (MuV; orthorubulavirus parotitidis) causes various complications and serious sequelae, such as meningitis, encephalitis, deafness, and impaired fertility. Direct-acting antivirals (DAAs) targeting MuV which can prevent mumps and mumps-associated complications and sequelae are yet to be developed. Paramyxoviridae family members, such as MuV, possess viral surface hemagglutinin-neuraminidase (HN) protein with sialidase activity which facilitates efficient viral replication. Therefore, to develop DAAs targeting MuV we synthesized MuV sialidase inhibitors. It is proposed that the viral HN has a single functional site for N-acetylneuraminic acid (Neu5Ac) binding and sialidase activity. Further, the known MuV sialidase inhibitor is an analog of Neu5Ac-2,3-didehydro-2-deoxy-N-acetylneuraminic acid (DANA)-which lacks potency. DANA derivatives with higher MuV sialidase inhibitory potency are lacking. The MuV-HN-Neu5Ac binding site has a hydrophobic cavity adjacent to the C4 position of Neu5Ac. Exploiting this, here, we synthesized DANA derivatives with increasing hydrophobicity at its C4 position and created 3 novel sialidase inhibitors (Compounds 1, 2 and 3) with higher specificity for MuV-HN than DANA; they inhibited MuV replication step to greater extent than DANA. Furthermore, they also inhibited hemagglutination and the MuV infection step. The insight-that these 3 novel DANA derivatives possess linear hydrocarbon groups at the C4-hydroxyl group of DANA-could help develop highly potent sialidase inhibitors with high specificity for MuV sialidase, which may function as direct-acting MuV-specific antivirals.

3.
PLoS One ; 13(7): e0200761, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30001430

RESUMEN

Immunochromatographic kits and RT-PCR are widely used as diagnostic tools for influenza detection in clinical and hygiene fields. Immunochromatographic kits are useful for differential typing of influenza A and influenza B but cannot show if the detected virus strains have acquired drug resistance against neuraminidase inhibitors that target sialidase activity of viral neuraminidase. Although RT-PCR enables determination of drug-resistant mutants, its efficacy is limited to viruses carrying a known substitution in their neuraminidase genome sequence. In the present study, an easy, rapid and sensitive method for detection of drug-resistant influenza viruses regardless of major antigenic changes or genomic mutations was developed. By using the method in combination with virus-concentrated membranes in centrifugal filter units and a sialidase imaging probe, 2-(benzothiazol-2-yl)-4-bromophenyl-N-acetylneuraminic acid (BTP3-Neu5Ac), sialidase activity of influenza neuraminidase was visualized on membranes by the green fluorescence of produced hydrophobic BTP3 under UV irradiation with a handheld UV flashlight. Fluorescence images in the presence or absence of neuraminidase inhibitors clearly discriminated drug-resistant influenza viruses from drug-sensitive ones. The assay can be done within 15 min. The detection sensitivity was shown to be equal to or higher than the sensitivities of commercial immunochromatographic kits. The assay will be a powerful tool for screening and monitoring of emerging drug-resistant influenza viruses and would help clinicians decide effective antiviral treatment strategies when such mutants have become prevalent.


Asunto(s)
Gripe Humana/diagnóstico , Ácido N-Acetilneuramínico/química , Neuraminidasa/química , Orthomyxoviridae/aislamiento & purificación , Animales , Antivirales/farmacología , Bioensayo , Línea Celular , Chlorocebus aethiops , Cromatografía de Afinidad , Perros , Farmacorresistencia Viral/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Fluorescencia , Colorantes Fluorescentes/farmacología , Humanos , Células de Riñón Canino Madin Darby , Imagen Óptica , Orthomyxoviridae/efectos de los fármacos , Oseltamivir/farmacología , Rayos Ultravioleta , Células Vero
4.
Neurobiol Dis ; 118: 142-154, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30026035

RESUMEN

Astrocyte-microglia communication influences the onset and progression of central nervous system (CNS) disorders. In this study, we determined how chronic inflammation by activated astrocytes affected and regulated CNS functions in Sandhoff disease (SD), a CNS lysosomal storage disorder. SD triggers intense CNS inflammation such as microglial activation and astrogliosis. It is caused by mutation of the HEXB gene, which reduces ß-hexosaminidase (Hex) enzymatic activity in lysosomes, leading to accumulation of the substrate GM2 ganglioside in neuronal cells. Hexb-/- mice display a phenotype similar to human patients that suffer from chronic inflammation characterized by activation of astrocytes and microglia. In Hexb-/- mice, tremors and loss of muscle coordination begins at ~12 weeks. Interestingly, we found that reactive astrocytes expressed adenosine A2A receptor in the cerebral cortices of Hexb-/- mice at the later inflammatory phase. In cultured astrocytes, expression of A2A receptor could be induced by astrocyte defined medium, and then the activation of the A2A receptor induced ccl2 expression. In Hexb-/- mice, inhibition of the A2A receptor antagonized by istradefylline decreased the number of activated microglial cells and inflammatory cytokines/chemokines at 13 weeks. Thus, the astrocytic A2A receptor is an important sensor that regulates microglial activation in the late phase of inflammation.


Asunto(s)
Antagonistas del Receptor de Adenosina A2/farmacología , Astrocitos/metabolismo , Modelos Animales de Enfermedad , Microglía/metabolismo , Receptor de Adenosina A2A/metabolismo , Enfermedad de Sandhoff/metabolismo , Antagonistas del Receptor de Adenosina A2/uso terapéutico , Animales , Astrocitos/efectos de los fármacos , Células Cultivadas , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microglía/efectos de los fármacos , Purinas/farmacología , Purinas/uso terapéutico , Enfermedad de Sandhoff/tratamiento farmacológico , Enfermedad de Sandhoff/genética
5.
Soc Neurosci ; 13(5): 553-565, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-28803529

RESUMEN

A dominant theory of humor comprehension suggests that people understand humor by first perceiving some incongruity in an expression and then resolving it. This is called "the incongruity-resolution theory." Experimental studies have investigated the neural basis of humor comprehension, and multiple neural substrates have been proposed; however, the specific substrate for incongruity resolution is still unknown. The reason may be that the resolution phase, despite its importance in humor comprehension, has not been successfully distinguished from the perception phase because both phases occur almost simultaneously. To reveal the substrate, we conducted a functional magnetic resonance study using 51 healthy participants. We used a humor-producing frame of "Given A, I'd say B, because C" so as to focus on the resolution phase independently by suspending humor processing just after the perception phase. This frame allowed us to separate the two phases. Based on our results, incongruity resolution evoked positive emotion and activated the left amygdala, which is known to be related to positive emotion. On the basis of these findings, we argue that the amygdala plays an important role in humor comprehension, considering its functional role in emotional evaluation, particularly the relevance detection for incoming stimuli.


Asunto(s)
Amígdala del Cerebelo/fisiología , Comprensión/fisiología , Emociones/fisiología , Estimulación Luminosa/métodos , Ingenio y Humor como Asunto , Adulto , Amígdala del Cerebelo/diagnóstico por imagen , Femenino , Humanos , Masculino , Proyectos Piloto , Desempeño Psicomotor/fisiología , Ingenio y Humor como Asunto/psicología , Adulto Joven
6.
J Vet Med Sci ; 78(9): 1521-1524, 2016 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-27264611

RESUMEN

Data from 48,187 cats insured between April 2012 and March 2013 were analyzed using logistic regression analysis to determine the association of age, breed and sex with the occurrence of urinary disorders. The overall annual prevalence of urinary disorders was 12.2%. Using crossbreeds as the reference breed, Abyssinian cats had the highest odds of having urinary disorders with a ratio of 1.40 (95% confidence interval: 1.20-1.63), followed by Norwegian Forest Cats and Somalis. Male cats had higher odds of having urinary disorders with a ratio of 1.27 (1.20-1.35) over female cats. Older cats had higher odds of having urinary disorders than young cats.


Asunto(s)
Enfermedades de los Gatos/epidemiología , Japón/epidemiología , Enfermedades Urológicas/veterinaria , Factores de Edad , Animales , Enfermedades de los Gatos/etiología , Gatos , Femenino , Seguro , Masculino , Factores de Riesgo , Factores Sexuales , Especificidad de la Especie , Enfermedades Urológicas/epidemiología , Enfermedades Urológicas/etiología
7.
Neuroimage ; 134: 522-531, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27107469

RESUMEN

Activation of the sympathetic nervous system is essential for coping with environmental stressors such as fearful stimuli. Recent human imaging studies demonstrated that activity in some cortical regions, such as the anterior cingulate cortex (ACC) and anterior insula cortex (aIC), is related to sympathetic activity. However, little is known about the functional brain connectivity related to sympathetic response to fearful stimuli. The participants were 32 healthy, right-handed volunteers. Functional magnetic resonance imaging (fMRI) was used to examine brain activity when watching horror and control movies. Fingertip temperature was taken during the scanning as a measure of sympathetic response. The movies were watched a second time, and the degree of fear (9-point Likert-type scale) was evaluated every three seconds. The brain activity of the ACC, bilateral aIC, and bilateral anterior prefrontal cortex (aPFC) was correlated with the change rate of fingertip temperature, with or without fearful stimuli. Functional connectivity analysis revealed significantly greater positive functional connectivity between the amygdala and the ACC and between the amygdala and the aIC when watching the horror movie than when watching the control movie. Whole-brain psycho-physiological interaction (PPI) analysis revealed that the functional connectivity between the left amygdala and the ACC was modulated according to the fear rating. Our results indicate that the increased functional connectivity between the left amygdala and the ACC represents a sympathetic response to fearful stimuli.


Asunto(s)
Encéfalo/fisiología , Miedo/fisiología , Sistema Nervioso Simpático , Adulto , Amígdala del Cerebelo/fisiología , Temperatura Corporal , Mapeo Encefálico , Corteza Cerebral/fisiología , Femenino , Giro del Cíngulo/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/fisiología , Corteza Prefrontal/fisiología , Adulto Joven
8.
Asian J Psychiatr ; 17: 89-93, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26310381

RESUMEN

Reactive attachment disorder (RAD) is characterized by markedly disturbed and developmentally inappropriate social relatedness due to parental maltreatment. RAD patients often display a high number of comorbid attention deficit/hyperactivity disorder (ADHD) symptoms, and certain RAD symptoms are difficult to discriminate from ADHD. One of the core characteristics of ADHD is a decrease in neural reward processing due to dopamine dysfunction. The aim of the present study was to determine whether the brain activity involved in reward processing in RAD patients is impaired in comparison with ADHD patients and typically developed controls. Five RAD patients, 17 typically developed (TD) controls and 17 ADHD patients aged 10-16 years performed tasks with high and low monetary reward while undergoing functional magnetic resonance imaging. ADHD patients were tested before and after 3 months treatment with osmotic release oral system-methylphenidate. Before treatment, ADHD patients showed that striatal and thalamus activities only in the tasks with low monetary reward were lower than TD controls. RAD patients showed decrease in activity of the caudate, putamen and thalamus during both the high and low monetary reward conditions in comparison with all the other groups. In RAD patients, the activity of the putamen was associated with the severity of posttraumatic stress and overt dissociation. Reward sensitivity was markedly decreased in children and adolescents with RAD, as evidenced by a diminished neural response during reward perception. This suggests that dopaminergic dysfunction exists in these patients, and may inform future dopaminergic treatment strategies for RAD.


Asunto(s)
Encéfalo , Neuronas Dopaminérgicas , Metilfenidato , Trastorno de Vinculación Reactiva , Recompensa , Conducta Social , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Trastorno por Déficit de Atención con Hiperactividad/metabolismo , Encéfalo/metabolismo , Encéfalo/fisiopatología , Niño , Maltrato a los Niños/psicología , Inhibidores de Captación de Dopamina/administración & dosificación , Inhibidores de Captación de Dopamina/farmacocinética , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Metilfenidato/administración & dosificación , Metilfenidato/farmacocinética , Proyectos Piloto , Trastorno de Vinculación Reactiva/diagnóstico , Trastorno de Vinculación Reactiva/metabolismo , Trastorno de Vinculación Reactiva/fisiopatología , Trastorno de Vinculación Reactiva/psicología , Análisis y Desempeño de Tareas
9.
J Correct Health Care ; 20(2): 154-62, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24659762

RESUMEN

Several inmates from a non-air-conditioned prison were sent to the University of Texas Medical Branch dermatology clinic for unexplained eruptions not responding to various treatments. They were initially diagnosed with Malassezia folliculitis based on clinical examination and histological findings. The patients' cultures from skin scrapings, however, revealed Candida albicans confirmed by growth on Mycosel agar and further by the germ tube production method. Five cases were brought to the clinic, but at least 30 other inmates were reported to have similar cutaneous eruptions. Given that these patients were generally immunocompetent, this is a rare finding. Factors favoring pseudohyphal growth for these patients included use of topical steroids and/or systemic antibiotics and hot and humid climate. All patients' folliculitis resolved with fluconazole and/or antifungal cream with no further complications.


Asunto(s)
Brotes de Enfermedades , Foliculitis/diagnóstico , Prisioneros/estadística & datos numéricos , Prisiones/estadística & datos numéricos , Adulto , Candida albicans/aislamiento & purificación , Candidiasis/diagnóstico , Candidiasis/epidemiología , Candidiasis/microbiología , Dermatomicosis/diagnóstico , Dermatomicosis/epidemiología , Dermatomicosis/microbiología , Diagnóstico Diferencial , Foliculitis/epidemiología , Foliculitis/microbiología , Humanos , Malassezia/aislamiento & purificación , Masculino , Persona de Mediana Edad
11.
Cytotherapy ; 14(7): 791-801, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22494074

RESUMEN

BACKGROUND AIMS: Although bone marrow (BM) stromal cells (SC; BMSC) isolated from adherent cultures of untreated BM are known to contain both committed and uncommitted osteogenic cells, it remains unknown whether BMSC isolated either by hemolysis or Ficoll centrifugation also contain both of these populations. METHODS: Differences in the osteogenic cell populations of rat BMSC isolated from untreated, hemolyzed or Ficoll-treated BM were analyzed by in vivo transplantation, flow cytometry, alkaline phosphatase (ALP) assay, real-time polymerase chain reaction (PCR) and alizarin red staining. RESULTS: Transplantation of non-cultured samples indicated that the Ficolled BMSC contained the lowest number of committed osteogenic cells. Flow cytometric analysis of cultured, non-induced samples showed that the percentage of ALP-positive cells was significantly lower in Ficolled BMSC. Quantitative ALP assays confirmed that the lowest ALP activity was in the Ficolled BMSC. Hemolyzed BMSC also contained lower numbers of committed osteogenic cells than untreated BMSC, but still more than Ficolled BMSC. Interestingly, the Ficolled BMSC showed the greatest levels of osteogenic ability when cultured in osteogenic induction medium. CONCLUSIONS: These findings suggest that, although Ficolled BMSC rarely contain committed osteogenic cells, they are able to show comparable or even greater levels of osteogenic ability after induction, possibly because they contain a greater proportion of uncommitted stem cells. In contrast, induction is optional but recommended for both untreated and hemolyzed BMSC before use, because both these groups contain both committed and uncommitted osteogenic cells. These findings are of significant importance when isolating BMSC for use in bone tissue engineering.


Asunto(s)
Diferenciación Celular , Hemólisis , Células Madre Mesenquimatosas , Osteogénesis/efectos de los fármacos , Fosfatasa Alcalina/análisis , Animales , Médula Ósea/metabolismo , Trasplante de Médula Ósea , Técnicas de Cultivo de Célula , Ficoll/farmacología , Citometría de Flujo , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratas
12.
Dermatol Online J ; 17(9): 1, 2011 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-21971266

RESUMEN

Cadaveric allografts and a large variety of other biologic dressings have been reported as being useful for the postoperative management of Mohs micrographic surgery (MMS) wounds. Although the use of porcine xenografts for the immediate postoperative management of these wounds is known, their use has not been detailed in the dermatology literature. A case series of 15 consecutive Mohs micrographic surgery patients (mean age = 74.9 years, range = 49 to 89 years) with wounds initially managed with porcine xenografts is described. Porcine xenografts were useful in a variety of clinical settings following MMS. These included: (1) wound management when tumor margins were indeterminate pending additional dermatopathology studies and (2) wound management when there are issues such as through and through nasal defects involving the mucosa, large wound depth, exposed cartilage and or bone, or patient medical comorbidities that delay or prevent plans for immediate wound reconstruction. Future controlled studies of biologic dressings are needed to determine which options are best for micrographic surgery wounds. Comparisons should also include the traditional option of second intention healing without biologic dressings.


Asunto(s)
Apósitos Biológicos , Carcinoma Basocelular/cirugía , Peca Melanótica de Hutchinson/cirugía , Cirugía de Mohs , Neoplasias Cutáneas/cirugía , Anciano , Anciano de 80 o más Años , Materiales Biocompatibles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , Cicatrización de Heridas
13.
Tissue Eng Part A ; 16(2): 663-73, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19754223

RESUMEN

Although human bone marrow stromal cells (BMSCs) have the ability to form bone when transplanted, the responsible factors for in vivo osteogenic abilities are poorly understood. Here we report conditions that are required for human BMSCs to demonstrate their in vivo osteogenic abilities. BMSCs were obtained from healthy donors and their in vivo osteogenic abilities were analyzed. Transplantation analyses revealed that the passage number and length of osteogenic induction significantly affected ectopic bone formation. Although 2-week induction increased the percentage of success in bone formation compared with the 1-week induction, BMSCs completely lost their in vivo osteogenic ability after passage 4 regardless of the length of osteogenic induction. Despite their in vivo osteogenic ability, no significant difference was observed in alkaline phosphatase activity or gene expression of osteogenic markers between BMSCs at passages 1 and 3. Differences were only observed in in vitro mineralizing abilities. Application of basic fibroblast growth factor helped to maintain the BMSCs in vivo osteogenic ability; basic fibroblast growth factor altered cell growth and expression of HLA-DR. The results strongly suggest that there are several required conditions for human BMSCs to demonstrate their bone-forming capabilities, which should be further investigated and considered when designing a protocol for clinical bone tissue engineering.


Asunto(s)
Células de la Médula Ósea/citología , Técnicas de Cultivo de Célula/métodos , Osteogénesis/fisiología , Adulto , Fosfatasa Alcalina/metabolismo , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/enzimología , Recuento de Células , Proliferación Celular/efectos de los fármacos , Femenino , Factor 2 de Crecimiento de Fibroblastos/farmacología , Humanos , Masculino , Osteogénesis/efectos de los fármacos , Células del Estroma/citología , Células del Estroma/efectos de los fármacos , Células del Estroma/enzimología , Células del Estroma/trasplante , Factores de Tiempo
14.
Biochem Biophys Res Commun ; 382(2): 353-8, 2009 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-19281797

RESUMEN

Current standard techniques for bone tissue engineering utilize ex vivo expanded osteogenic cells. However, ex vivo expansion requires serum, which may hinder clinical applications. Here, we report the feasibility and efficacy of bone tissue engineering with human bone marrow stromal cells (BMSCs) expanded in serum-free conditions. Bone marrow was aspirated from 4 healthy donors and adherent cells were cultured in either serum-free medium (STEMPRO((R)) MSC SFM) or conventional serum-containing medium (alpha-MEM supplemented with 10% serum). Efficacy of expansion was greater in serum-free medium. Phenotypically, serum-free expanded BMSCs were smaller in cell-size and showed expression of CD105(++) and CD146(dim). After osteogenic induction, serum-free expanded BMSCs showed lower alkaline phosphatase activity. However, they showed higher responsiveness to induction. In vivo bone-forming ability was also confirmed. In conclusion, bone tissue engineering with serum-free expanded BMSCs is feasible and as efficient as that obtained with BMSCs expanded in conventional serum-containing medium.


Asunto(s)
Células de la Médula Ósea/fisiología , Huesos/fisiología , Osteogénesis , Ingeniería de Tejidos/métodos , Antígenos CD/análisis , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Huesos/citología , Técnicas de Cultivo de Célula , Tamaño de la Célula , Medio de Cultivo Libre de Suero/farmacología , Endoglina , Humanos , Receptores de Superficie Celular/análisis , Células del Estroma/citología , Células del Estroma/efectos de los fármacos , Células del Estroma/fisiología , Molécula 1 de Adhesión Celular Vascular/análisis
15.
J Am Acad Dermatol ; 60(1): 157-61, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19103370

RESUMEN

The term Richter syndrome (RS) describes the transformation of chronic lymphocytic leukemia into a high-grade lymphoma. RS occurs in 3% to 10% of chronic lymphocytic leukemia cases, and its onset is often characterized by the abrupt development of systemic symptoms (eg, fever in the absence of infection, night sweats, and weight loss), progressive lymphadenopathy, and hepatosplenomegaly. RS frequently arises in the lymph nodes or bone marrow, and rarely presents with extranodal involvement, which includes the gastrointestinal tract, eye, testis, central nervous system, lung, kidney, and skin. We review the literature regarding the clinical course and treatment of RS, present a patient with primary cutaneous RS, and discuss the prognostic implications.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/patología , Linfoma no Hodgkin/patología , Neoplasias Cutáneas/patología , Anciano , Humanos , Masculino , Pronóstico , Síndrome
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA