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1.
Anaesth Rep ; 8(2): 135-137, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33210091

RESUMEN

Myotonic dystrophy type 1 is the most common muscular dystrophy in adults. Anaesthetic management should take into consideration the numerous body systems affected, including the musculoskeletal; respiratory; cardiovascular; gastro-intestinal; and central nervous systems. A 42-year-old man with myotonic dystrophy presented for septoplasty and bilateral inferior turbinate reductions. He had severe upper and lower extremity myotonia and weakness, pulmonary impairment with non-obstructive patterns and first-degree atrioventricular block with reduced ejection fraction. He used bilevel positive airway pressure, a cough assist device and was paced 3% of the time with a single-chamber pacemaker. To reduce potential complications associated with opioid use and general anaesthetics, an opioid-free technique was planned using local anaesthetic infiltration and sedation with a dexmedetomidine infusion. The patient maintained spontaneous ventilation and haemodynamic stability, and had an uneventful postoperative course. Dexmedetomidine is a highly selective α2-adrenergic receptor agonist that has the ability to provide sedation, analgesia and anxiolysis with a stable haemodynamic profile. Avoiding both opioids and general anaesthetics in these patients may decrease the risk of peri-operative complications.

2.
Clin Exp Immunol ; 180(3): 509-19, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25652232

RESUMEN

Infants exposed to maternal HIV-1 provide an opportunity to assess correlates of HIV-1-specific interferon (IFN)-γ responses and may be informative in the development of HIV-1 vaccines. HIV-1-infected women with CD4 counts 200-500 cells/mm(3) were randomized to short-course zidovudine/nevirapine (ZDV/NVP) or highly active anti-retroviral therapy (HAART) between 2003 and 2005. Maternal plasma and breastmilk HIV-1 RNA and DNA were quantified during the first 6-12 months postpartum. HIV-1 gag peptide-stimulated enzyme-linked immunospot (ELISPOT) assays were conducted in HIV-1-exposed, uninfected infants (EU), and correlates were determined using regression and generalized estimating equations. Among 47 EU infants, 21 (45%) had ≥1 positive ELISPOT result during follow-up. Infants had a median response magnitude of 177 HIV-1-specific spot-forming units (SFU)/106 peripheral blood mononuclear cells (PBMC) [interquartile range (IQR)=117-287] directed against 2 (IQR = 1-3) gag peptide pools. The prevalence and magnitude of responses did not differ by maternal anti-retroviral (ARV) randomization arm. Maternal plasma HIV-1 RNA levels during pregnancy (P=0.009) and breastmilk HIV-1 DNA levels at 1 month (P=0.02) were associated with a higher magnitude of infant HIV-1-specific ELISPOT responses at 1 month postpartum. During follow-up, concurrent breastmilk HIV-1 RNA and DNA (cell-free virus and cell-associated virus, respectively) each were associated positively with magnitude of infant HIV-1-specific responses (P=0.01). Our data demonstrate the importance of antigenic exposure on the induction of infant HIV-1-specific cellular immune responses in the absence of infection.


Asunto(s)
Infecciones por VIH/inmunología , Infecciones por VIH/virología , VIH-1/inmunología , Leche Humana/virología , Carga Viral , Adulto , Fármacos Anti-VIH/uso terapéutico , Terapia Antirretroviral Altamente Activa , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/metabolismo , Humanos , Inmunidad Celular , Lactante , Recién Nacido , Interferón gamma/sangre , Kenia , Embarazo , Adulto Joven
3.
Mucosal Immunol ; 8(3): 596-606, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25291985

RESUMEN

In contrast to resident constitutive mast cells (CMCs), mucosal MCs (MMCs) appear in the lung and trachea of sensitized mice only following inhalation challenge. We monitored the influx and maturation of MCs by their expression of Kit, FcɛRI, ß7-integrin and side scatter (SSC) by flow cytometry. Influx of MC progenitors (MCps) (FcɛRI(lo), Kit(int), ß7(hi), and SSC(lo)) peaks 1 day after challenges and subsides to baseline by day 7 after challenge. The mature MMCs appear as a distinct population on day 7 and peak at day 14 with higher SSC and FcɛRI expression, but lower ß7 and Kit expression. A distinct transitional population is present between 1 and 7 days after challenge. Maturation occurs more rapidly in the trachea. The resident tracheal CMCs had higher SSC, FcɛRI, and Kit and lower ß7-integrin expression than the MMCs. By histology, the MMCs follow similar kinetics to the flow cytometry-identified mature MMCs and are notably persistent for >42 days. Steroid treatment reduced inflammation and MCp influx but had no effect on established MMCs. Thus, changes in SSC, FcɛRI, and Kit together with the expression of αE/α4:ß7-integrins characterizes the development of induced MMCs from MCps and distinguishes them from resident CMCs in the trachea and large airways.


Asunto(s)
Mastocitos/inmunología , Neumonía/inmunología , Hipersensibilidad Respiratoria/inmunología , Células Madre/inmunología , Tráquea/inmunología , Animales , Antiinflamatorios/farmacología , Diferenciación Celular , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Cadenas beta de Integrinas/genética , Cadenas beta de Integrinas/inmunología , Mastocitos/patología , Ratones , Ratones Endogámicos BALB C , Ovalbúmina , Neumonía/inducido químicamente , Neumonía/tratamiento farmacológico , Neumonía/genética , Prednisona/farmacología , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/inmunología , Receptores de IgE/genética , Receptores de IgE/inmunología , Hipersensibilidad Respiratoria/inducido químicamente , Hipersensibilidad Respiratoria/tratamiento farmacológico , Hipersensibilidad Respiratoria/genética , Transducción de Señal , Células Madre/patología , Tráquea/patología
4.
Phys Rev Lett ; 112(17): 176404, 2014 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-24836262

RESUMEN

We employ an exact solution of the simplest model for pump-probe time-resolved photoemission spectroscopy in charge-density-wave systems to show how, in nonequilibrium, the gap in the density of states disappears while the charge density remains modulated, and then the gap reforms after the pulse has passed. This nonequilibrium scenario qualitatively describes the common short-time experimental features in TaS(2) and TbTe(3), indicating a quasiuniversality for nonequilibrium "melting" with qualitative features that can be easily understood within a simple picture.

5.
HIV Med ; 15(7): 385-95, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24580813

RESUMEN

OBJECTIVES: Adherence is critical for maximizing the effectiveness of pre-exposure prophylaxis (PrEP) in preventing HIV infection. Strategies for promoting adherence to HIV treatment, and their potential application to PrEP adherence, have received considerable attention. However, adherence promotion strategies for prevention medications have not been well characterized and may be more applicable to PrEP. We aimed to identify adherence support interventions that have been effective in other prevention fields and could be applied in the HIV prevention context to support pill taking among PrEP users. METHODS: To identify adherence support interventions that could be evaluated and applied in the PrEP context, we conducted a systematic review across the following prevention fields: hypertension, latent tuberculosis infection, hyperlipidaemia, oral contraceptives, osteoporosis, malaria prophylaxis, and post-exposure prophylaxis for HIV infection. We included randomized controlled trials that evaluated the efficacy of interventions to improve adherence to daily oral medications prescribed for primary prevention in healthy individuals or for secondary prevention in asymptomatic individuals. RESULTS: Our searches identified 585 studies, of which 48 studies met the eligibility criteria and were included in the review; nine evaluated multiple strategies, yielding 64 separately tested interventions. Interventions with the strongest evidence for improving adherence included complex, resource-intensive interventions, which combined multiple adherence support approaches, and low-cost, low-intensity interventions that provided education or telephone calls for adherence support. CONCLUSIONS: Our review identified adherence interventions with strong evidence of efficacy across prevention fields and provides recommendations for evaluating these interventions in upcoming PrEP studies.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/prevención & control , Cumplimiento de la Medicación , Prevención Primaria , Promoción de la Salud/métodos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
6.
Mol Biol (Mosk) ; 48(4): 682-6, 2014.
Artículo en Ruso | MEDLINE | ID: mdl-25842852

RESUMEN

The aim of the study was to explore the interactions of human papilloma virus 16 (HPV16) E2 protein and Daxx. The location or co-localization of PML and E2 with Daxx in Caski cells was observed by indirect immunofluorescence test. The interaction of E2 and Daxx was analyzed by co-immunoprecipitation, Western-blot and yeast-two hybrid assay. In Caski cells the fluorescence of Daxx or PML was mainly distributed in the cytoplasm or nucleus, respectively, and in the align image their signals did not overlapped. However, when the red signal of HPV16 E2 and the green signal of Daxx in cyto- plasm of Caski cells were merged, the yellow signals appeared. The yeast co-transformed with pGBKT7/Daxx and pGADT7/E2 or pGADT7/E2 TAD can grow onto SD/-Trp-Leu-His and SD/-Trp-Leu-His-Ade plates. So Daxx wasn't co-located with PML but with HPV16 E2 mainly in the cytoplasm of Caski cells. On the base of the results one can propose that HPV16 E2, in particularly its transcription-activity domain (TAD), interacts with Daxx.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Oncogénicas Virales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Western Blotting , Línea Celular , Núcleo Celular/metabolismo , Proteínas Co-Represoras , Citoplasma/metabolismo , Proteínas de Unión al ADN/genética , Humanos , Inmunoprecipitación , Chaperonas Moleculares , Mutación , Proteínas Nucleares/genética , Proteínas Oncogénicas Virales/genética , Proteína de la Leucemia Promielocítica , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Técnicas del Sistema de Dos Híbridos
7.
Plant Dis ; 98(7): 994, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30708915

RESUMEN

Mangosteen (Garcinia mangostana L., Guttiferae) is a tropical fruit renowned for its pleasant taste, rich nutrition, and medicinal value. Little research about mangosteen diseases during storage and transport has been reported. In June of 2012, fruit rots on mangosteens imported from Thailand were observed in Guangzhou, China. In infected fruits, pericarps showed an increased firmness, were discolored to deep pink, and the edible aril became brown and rotten. In order to search for the etiological agent of this rot symptom, infected mangosteens were analyzed. Diseased mangosteen tissues were surface-sterilized with 70% alcohol, then with 0.1% HgCl2, dipped in sterilized water three times, and placed onto potato dextrose agar (PDA) at 26°C. The fungi isolated from tissues of the pericarp and aril were similar in morphology and grew rapidly, covering the plate surface (9 mm diameter) after 2 to 3 days of incubation at 26°C. The morphological characters of 10 single-spore isolates were observed. These isolates showed light yellow to light brown fertile colonies on PDA. On corn meal agar (CMA), conidiophores were erect, arising from wide hyphae; they were composed of a basal stipe ending in a penicillate conidiogenous apparatus with directly subtending sterile stipe extensions ranging from 74.5 to 195.0 µm long. Conidia were unicellular, smooth, oblong to elliptical, 6.3 to 8.5 × 2.5 to 3.0 µm, and accumulated in a mucilaginous mass. Chlamydospores were multicellular, dark brown, regular in shape and thick-walled, and 40.0 to 52.5 µm in diameter. On the basis of these morphological characters, these isolates were identified as Gliocephalotrichum bulbilium (2). To confirm the identity of this fungus, genomic DNA of two isolates was extracted, and fragments of ITS region and ß-tubulin gene were amplified by PCR, sequenced, and compared with sequences of Gliocephalotrichum species available in NCBI GenBank. Both DNA regions (GenBank Accession Nos. KF716166 and KF716168) had sequence similarities of 99% and 97%, respectively, to other G. bulbilium sequences at GenBank. Pathogenicity tests were conducted on three detached fruits for two isolates. Fruits were inoculated using 5-mm mycelial disks with conidia taken from 3-day-old cultures of G. bulbilium isolate Gb1 and Gb10 grown on PDA. Controls were inoculated with PDA disks only. All treated fruits were kept individually in a humid chamber at 26°C. Tests were repeated twice. Three days after inoculation, white mycelial growth for Gb was observed at inoculation sites. Eight days after inoculation, mycelium of Gb nearly covered the fruit, causing fruit rot, and the pericarp became hard and light in color. The control fruit did not rot. G. bulbilium was re-isolated from diseased plant tissue, thus fulfilling Koch's postulates. G. bulbilium has been reported causing postharvest fruit rot of rambutan (Nephelium lappaceum) and guava (Psidium guajava) in some locations (3,4). Moreover, the fungus caused cranberry fruit rot in the United States (1). To our knowledge, this is the first report of G. bulbilium causing postharvest fruit rot of mangosteen in China. It is uncertain whether the fungus infected mangosteen in Thailand and was carried to China due to commercial relationship. References: (1) C. Constantelos et al. Plant Dis. 95:618, 2011. (2) C. Decock et al. Mycologia 98:488, 2006. (3) L. M. Serrato-Diaz et al. Plant Dis. 96:1225, 2012. (4) A. Sivapalan et al. Australas. Plant Pathol. 27:274, 1998.

8.
J Nanosci Nanotechnol ; 12(8): 6480-3, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22962769

RESUMEN

In this paper, we use a simple and highly-effective pulsed laser reducing method to fabricate flexible, transparent and conducting graphene film. The pulsed laser reducing process was monitored by digital camera and UV-visible spectroscopy. The obtained reduced graphene oxide (r-GO) was characterized by Raman spectroscopy. Based on this reducing method, the resulting r-GO films possessed a transmittance varied from 29% to 74% and a sheet resistance varied from 2.1 MΩ/[square] to 840 Ω/[square], which was very close to chemically r-GO film.

9.
J Anim Breed Genet ; 129(4): 257-70, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22775258

RESUMEN

Theory hypothesizes that the rate of decline in linkage disequilibrium (LD) as a function of distance between markers, measured by r(2), can be used to estimate effective population size (N(e)) and how it varies over time. The development of high-density genotyping makes feasible the application of this theory and has provided an impetus to improve predictions. This study considers the impact of several developments on the estimation of N(e) using both simulated and equine high-density single-nucleotide polymorphism data, when N(e) is assumed to be constant a priori and when it is not. In all models, estimates of N(e) were highly sensitive to thresholds imposed upon minor allele frequency (MAF) and to a priori assumptions on the expected r(2) for adjacent markers. Where constant N(e) was assumed a priori, then estimates with the lowest mean square error were obtained with MAF thresholds between 0.05 and 0.10, adjustment of r(2) for finite sample size, estimation of a [the limit for r(2) as recombination frequency (c) approaches 0] and relating N(e) to c (1 - c/2). The findings for predicting N(e) from models allowing variable N(e) were much less clear, apart from the desirability of correcting for finite sample size, and the lack of consistency in estimating recent N(e) (<7 generations) where estimates use data with large c. The theoretical conflicts over how estimation should proceed and uncertainty over where predictions might be expected to fit well suggest that the estimation of N(e) when it varies be carried out with extreme caution.


Asunto(s)
Desequilibrio de Ligamiento , Modelos Genéticos , Animales , Frecuencia de los Genes/genética , Marcadores Genéticos/genética , Técnicas de Genotipaje , Caballos/genética , Polimorfismo de Nucleótido Simple/genética , Densidad de Población
10.
Genet Res (Camb) ; 92(2): 157-66, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20515518

RESUMEN

The incorporation of genetic information such as quantitative trait loci (QTL) data into breeding schemes has become feasible as DNA technologies have advanced. Such strategies allow the frequency of desirable QTL to be controlled over a predefined time frame, allowing the allele trajectory for QTL to be manipulated. A continuous approximation to changes in allele frequency was developed to approximate the selection procedure as a continuous rather than a discrete process, and analytical solutions were obtained, which shed light on how allele trajectories behave under different objective functions. Three different objectives were considered: (1) minimizing the total selection intensity, (2) minimizing the sum of squared selection intensities and (3) equalizing the selection intensity applied over time. Simulations and genetic algorithms were performed to test the accuracy and robustness of the continuous approximation. Theory shows firstly that the total selection intensity required for moving an allele from a starting frequency to another frequency point can be predicted independent of its trajectory, and secondly that objectives (2) and (3) are equivalent as the number of selection opportunities (T) becomes large. The prediction of total selection intensity provides a good fit for these two objectives, with the accuracy of prediction improving as T increases. However, for (1) the continuous approximation does not fit due to the existence of a discontinuous solution in which the continuous approximation is applied before the frequency of the selected allele reaches 0.5 followed by rapid fixation.


Asunto(s)
Alelos , Sitios de Carácter Cuantitativo/genética , Animales , Cruzamiento , Simulación por Computador , Frecuencia de los Genes , Genética de Población
11.
Cell Tissue Res ; 305(3): 389-97, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11572092

RESUMEN

Cultured prostatic epithelial cells have been extensively studied as a model of prostate biology. What is the lineage relationship of the cultured cells to the epithelial cell types in tissue? How different are cultured cells derived from tumor tissue to those derived from benign tissue? Expression of cluster designation (CD) cell surface molecules has been shown to be useful in characterizing cells according to lineage. A CD profile was therefore generated for cultured human prostatic epithelial cells and compared with those previously established for basal and luminal epithelial cells in the prostate. Presence of CD44, CD49b, CD49f, and CD104 and absence of CD57 suggests that cultured cells were derived from basal cells of prostatic tissues. However, expression of certain CD antigens characteristic of luminal epithelial cells was also observed in subpopulations of cultured cells. The pattern of CD antigens in cultured cells reflects a phenotype similar to that of transit-amplifying cells that have been described in the prostate. Several CD antigens were found expressed by both cultured prostatic epithelial and stromal cells, and are probably associated with cell proliferation. The CD profiles of cultured epithelial cell strains derived from normal compared with malignant tissues were notably similar to each other and to that of the prostate cancer cell line PC-3. We conclude that cells in culture retain expression of certain lineage-characteristic CD antigens. Furthermore, CD antigens can define subpopulations of cells with differential gene expression.


Asunto(s)
Antígenos CD/análisis , Antígenos CD/genética , Células Epiteliales/química , Neoplasias de la Próstata , Anciano , Cartilla de ADN , Células Epiteliales/citología , Células Epiteliales/fisiología , Regulación Neoplásica de la Expresión Génica , Humanos , Receptores de Hialuranos/análisis , Receptores de Hialuranos/genética , Integrina alfa2 , Integrina alfa6 , Integrina beta4 , Masculino , Fenotipo , Células del Estroma/química , Células del Estroma/citología , Células del Estroma/fisiología , Células Tumorales Cultivadas
12.
Diagn Mol Pathol ; 10(3): 161-5, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11552718

RESUMEN

The authors report two cases of the rare primary gastric choriocarcinoma. These tumors showed an overwhelming predominance of cytotrophoblast- and syncytiotrophoblast-like tumor cells that were positive for beta-human chorionic gonadotrophin, with small foci of glandular differentiation. Beta-human chorionic gonadotrophin was also detected serologically in one patient. Comparative genomic hybridization study was performed on one specimen. Copy number gains of chromosomes 12, 17, 20, 22, and X, together with losses on 18q, were the major findings. Except for the gain of chromosome 12, which is known to be uncommon in primary gastric adenocarcinoma but frequently associated with choriocarcinoma, the remaining genomic imbalances were among the most common comparative genomic hybridization findings reported in primary gastric adenocarcinoma. Fluorescence in situ hybridization on paraffin sections of both specimens confirmed the presence of polysomy 17 and trisomy 12. These results suggest that primary gastric choriocarcinoma genetically possesses characteristics of both adenocarcinoma and gestational choriocarcinoma. The authors believe this is the first interphase cytogenetics study on this rare tumor, and that the results support the theory that gastric choriocarcinoma arises from alternate differentiation pathways of adenocarcinoma.


Asunto(s)
Adenocarcinoma/genética , Coriocarcinoma/genética , Neoplasias Gástricas/genética , Neoplasias Uterinas/genética , Adenocarcinoma/química , Adenocarcinoma/patología , Anciano , Aneuploidia , Biomarcadores de Tumor/análisis , Coriocarcinoma/química , Coriocarcinoma/secundario , Coriocarcinoma/cirugía , Gonadotropina Coriónica Humana de Subunidad beta/análisis , ADN de Neoplasias/análisis , Resultado Fatal , Femenino , Dosificación de Gen , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/química , Neoplasias Gástricas/patología , Neoplasias Gástricas/cirugía , Neoplasias Uterinas/química , Neoplasias Uterinas/patología
13.
AJNR Am J Neuroradiol ; 22(8): 1597-601, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11559514

RESUMEN

Hyperperfusion syndrome is a well-documented complication of carotid endarterectomy, as well as internal carotid artery angioplasty and stent placement. We report a similar complication after distal intracranial (middle cerebral artery [MCA] M2 segment) angioplasty. To our knowledge, this is the first report of hyperperfusion syndrome after intracranial angioplasty of a distal MCA branch.


Asunto(s)
Angioplastia/efectos adversos , Arteriopatías Oclusivas/cirugía , Arterias Cerebrales , Hemorragia Cerebral/etiología , Hiperemia/etiología , Anciano , Anciano de 80 o más Años , Arteriopatías Oclusivas/diagnóstico , Angiografía Cerebral , Constricción Patológica/diagnóstico , Constricción Patológica/cirugía , Resultado Fatal , Femenino , Humanos , Síndrome , Tomografía Computarizada por Rayos X
14.
J Cell Biochem ; 82(2): 326-38, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11527157

RESUMEN

The role of c-Jun NH2-terminal kinase (JNK) signaling cascade in the stress-inducible phosphorylation of heat shock factor 1 (HSF1) was investigated using known agonists and antagonists of JNK. We showed that treatment of HeLa cells with MG132, a proteasome inhibitor and known INK activator, caused the transcriptional activation domain of HSF1 to be targeted and phosphorylated by JNK2 in vivo. Dose-response and time course studies of the effects of heat shock and anisomycin treatment showed a close correlation of the activation of JNK and hyperphosphorylation of HSF1. SB203580 inhibited INK at the 100 microM concentration and significantly reduced the amount of hyperphosphorylated HSF1 upon heat shock or anisomycin treatment. SB203580 and dominant-negative JNK suppress hsp70 promoter-driven reporter gene expression selectively at 45 degrees C but not at 42 degrees C heat stress, suggesting that JNK would be preferentially associated with the protective heat shock response against severe heat stress. The possibility that JNK-mediated phosphorylation of HSF1 may selectively stabilize the HSF1 protein and confers protection to cells under conditions of severe stress is discussed.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica/fisiología , Proteínas Quinasas Activadas por Mitógenos/fisiología , Procesamiento Proteico-Postraduccional , Estrés Fisiológico/enzimología , Activación Transcripcional , Animales , Anisomicina/farmacología , Sitios de Unión , Cisteína Endopeptidasas/metabolismo , Proteínas de Unión al ADN/química , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas HSP70 de Choque Térmico/biosíntesis , Proteínas HSP70 de Choque Térmico/genética , Células HeLa/efectos de los fármacos , Células HeLa/enzimología , Factores de Transcripción del Choque Térmico , Calor , Humanos , Imidazoles/farmacología , Isoenzimas/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos , Leupeptinas/farmacología , Proteína Quinasa 9 Activada por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Complejos Multienzimáticos/antagonistas & inhibidores , Complejos Multienzimáticos/metabolismo , Fosforilación , Regiones Promotoras Genéticas/efectos de los fármacos , Inhibidores de Proteasas/farmacología , Complejo de la Endopetidasa Proteasomal , Estructura Terciaria de Proteína , Piridinas/farmacología , Conejos , Proteínas Recombinantes de Fusión/biosíntesis , Transducción de Señal/efectos de los fármacos , Estrés Fisiológico/genética , Factores de Transcripción , Activación Transcripcional/efectos de los fármacos , Transfección
15.
Phys Rev Lett ; 87(8): 087005, 2001 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-11497975

RESUMEN

Density-functional calculations of the phonon spectrum and electron-phonon coupling in MgB (2) are presented. The E(2g) phonons, which involve in-plane B displacements, couple strongly to the p(x,y) electronic bands. The isotropic electron-phonon coupling constant is calculated to be about 0.8. Allowing for different order parameters in different bands, the superconducting lambda in the clean limit is calculated to be significantly larger. The E(2g) phonons are strongly anharmonic, and the nonlinear contribution to the coupling between the E(2g) modes and the p(x,y) bands is significant.

16.
J Biol Chem ; 276(26): 23554-61, 2001 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-11320084

RESUMEN

We describe here an experimental protocol for the resolution, detection, and quantitation of the reduced and oxidized conformers of human heat shock factor 1 (hHSF1) and report on the effects in vitro and in vivo of redox-active agents on the redox status, structure, and function of hHSF1. We showed that diamide, a reagent that promotes disulfide bond formation, caused a loss of immunorecognition of the monomeric hHSF1 protein in a standard Western blot detection procedure. Modification of the Western blot procedure to include dithiothreitol in the equilibration and transfer buffers after gel electrophoresis allowed for the detection of a compact, intramolecularly disulfide cross-linked oxidized hHSF1 (ox-hHSF1) in the diamide-treated sample. The effect of diamide was blocked by pretreatment with N-ethylmaleimide and was reversed by dithiothreitol added to the sample prior to gel electrophoresis. Incubation with nitrosoglutathione at 42 degrees C also promoted the conversion of HSF1 to ox-HSF1; at 25 degrees C, however, nitrosoglutathione was by itself without effect but blocked the formation of ox-hHSF1 in the presence of diamide. The disulfide cross-linked ox-hHSF1 was monomeric and resistant to the in vitro heat-induced trimerization and activation. The possibility that ox-HSF1 may occur in oxidatively stressed cells was evaluated. Treatment of HeLa cells with 2 mm l-buthionine sulfoximine promoted the formation of ox-HSF1 and blocked the heat-induced activation of HSF DNA binding activity. Our result suggests that hHSF1 may have integrated redox chemistry of cysteine sulfhydryl into its functional responses.


Asunto(s)
Proteínas de Unión al ADN/análisis , Proteínas de Unión al ADN/metabolismo , Glutatión/análogos & derivados , Western Blotting/métodos , Butionina Sulfoximina/farmacología , Proteínas de Unión al ADN/química , Diamida/farmacología , Disulfuros/metabolismo , Ditiotreitol/química , Etilmaleimida/farmacología , Glutatión/farmacología , Células HeLa , Factores de Transcripción del Choque Térmico , Calor , Humanos , Óxido Nítrico/metabolismo , Compuestos Nitrosos/farmacología , Oxidación-Reducción , Conformación Proteica , S-Nitrosoglutatión , Reactivos de Sulfhidrilo/farmacología , Factores de Transcripción
17.
Acad Radiol ; 8(2): 137-48, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11227642

RESUMEN

RATIONALE AND OBJECTIVES: The purpose of this retrospective study was to estimate the economic consequences of evaluating suspected vocal cord paralysis with magnetic resonance (MR) imaging and computed tomography (CT). MATERIALS AND METHODS: Reports from MR imaging (n = 30) or CT (n = 19) studies of the neck in 49 patients were retrospectively reviewed for causes of vocal cord paralysis. The patients were divided into high-suspicion (n = 20) and low-suspicion (n = 29) groups, based on the presence or absence of a clinically detectable abnormality other than vocal cord immobility. Clinic and inpatient charts were examined to determine the work-up in all cases. The Medicare Resource-based Relative Value Scale was used to estimate the costs of most procedures. RESULTS: The high-clinical-suspicion group included nine true-positive, four false-positive, seven true-negative, and no false-negative cases. Further work-up was performed in seven true-positive, three false-positive, and one true-negative cases. The total cost of immediate diagnostic work-up in these 20 patients, including MR imaging and/or CT, was $20,737 ($2,304 per true-positive case). The low-suspicion group included two true-positive, nine false-positive, 18 true-negative, and no false-negative cases. Further work-up was performed in both true-positive, four false-positive, and two true-negative cases. The total cost of immediate diagnostic work-up in these 29 patients was $21,698, (mean, $748; $10,849 per true-positive case). CONCLUSION: The average cost of finding space-occupying lesions in patients with vocal cord paralysis is more than 4.5 times higher in patients without suspicious antecedent clinical findings than in those with such a history. The benefits of obtaining negative findings and of detecting a small number of space-occupying lesions should be weighed against the costs of such examinations and of additional work-up for false-positive findings.


Asunto(s)
Imagen por Resonancia Magnética/economía , Tomografía Computarizada por Rayos X/economía , Parálisis de los Pliegues Vocales/diagnóstico , Parálisis de los Pliegues Vocales/economía , Algoritmos , Análisis Costo-Beneficio , Reacciones Falso Positivas , Humanos , Medicare , Valor Predictivo de las Pruebas , Escalas de Valor Relativo , Estudios Retrospectivos , Sensibilidad y Especificidad , Estados Unidos , Parálisis de los Pliegues Vocales/diagnóstico por imagen , Parálisis de los Pliegues Vocales/etiología
19.
Neuroradiology ; 43(11): 918-26, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11760794

RESUMEN

The purpose of our study was to determine the usefulness of echo-planar diffusion-weighted imaging (EPDI) in the evaluation of watershed hypoxic-ischemic brain injury in pediatric patients. Eighteen patients ranging in age from 3 weeks to 12 years were evaluated for evidence of ischemic/infarction changes on conventional MR and EPDI. Included in the study group were five patients with sickle cell disease, four with congenital heart disease, four with hypotensive episodes with various etiologies, three with sepsis, and two with encephalitis or meningitis. Patients were examined 2 h to 6 days after the initial insult, with follow-up studies in four patients at 1 to 62 days after the initial examination. After conventional MR imaging (T1, FSE T2, and FLAIR), diffusion-weighted MR imaging was performed using high-speed, single-shot EP techniques with TR 6000, TE 144, matrix 96 x 128, FOV 23.3 x 31 and five b values of 0, 160, 360, 640, and 1,000 s/mm2. EPDI demonstrated abnormally increased signal in watershed ischemic/infarction zones in all initial cases. Apparent diffusion coefficients (ADC) were obtained in 59 lesions. When compared with radiographically normal (on EPDI) contralateral brain parenchyma, 45 demonstrated a relatively decreased ADC, while eight had normal ( +/- 10%) and six had increased ADC. In four cases, signal abnormalities on EPDI were not seen or exceeded that seen with conventional MR imaging. In the remaining cases, signal abnormalities were obvious on EPDI and more subtle on conventional MR imaging. Follow-up studies demonstrated resolution of abnormal EPDI signal with persistent abnormalities on conventional imaging in some cases, while others revealed an increase in size or number of EPDI signal abnormalities, suggesting ongoing acute ischemic/infarctive changes. EPDI is a rapid, sensitive technique for detecting watershed ischemic/infarction changes in pediatric patients with hypoperfusion episodes, at times before such changes are apparent on conventional MR images and/or are clinically apparent.


Asunto(s)
Encéfalo/patología , Imagen Eco-Planar , Hipoxia-Isquemia Encefálica/patología , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Factores de Tiempo
20.
Diagn Mol Pathol ; 10(4): 223-7, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11763312

RESUMEN

Epstein-Barr virus (EBV) genome can be found in many malignant tumors in China. Previous data of interphase cytogenetics, by comparative genomic hybridization and/or fluorescence in situ hybridization, on nasopharyngeal carcinomas and natural killer cell-type non-Hodgkin lymphomas in Hong Kong have noted gains in chromosome 11. This study compares the frequency of chromosome 11 copy number gains in three different types of EBV-associated tumors in Hong Kong. Using alpha-satellite probes, the authors studied by fluorescence in situ hybridization 31 EBV-positive tumors comprising 10 EBV-positive gastric carcinomas, 8 lung lymphoepithelioma-like carcinomas, and 13 non-Hodgkin lymphomas. Trisomy or polysomy 11 was detected in 10 of 10 (100%) EBV-positive gastric carcinomas, 6 of 8 (75%) lung lymphoepithelioma-like carcinomas, and 4 of 13 (30.8%) non-Hodgkin lymphomas. Compared with the EBV-positive gastric carcinomas, the 10 EBV-negative gastric carcinomas that were also studied showed chromosome 11 copy number gains in 3 of 10 (30%), a significantly lower frequency. The authors conclude that gains in chromosome 11 are common in EBV-associated malignancies in Hong Kong, with the strongest association found in gastric carcinoma. There seems to be differences between EBV-associated tumors of different locations, and between gastric carcinomas with and without EBV.


Asunto(s)
Cromosomas Humanos Par 11 , Infecciones por Virus de Epstein-Barr/genética , Dosificación de Gen , Neoplasias/genética , Adulto , Anciano , Anciano de 80 o más Años , Aneuploidia , Carcinoma/genética , Carcinoma/patología , Carcinoma/virología , ADN de Neoplasias/análisis , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/patología , Femenino , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Hibridación Fluorescente in Situ , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/virología , Linfoma no Hodgkin/genética , Linfoma no Hodgkin/patología , Linfoma no Hodgkin/virología , Masculino , Persona de Mediana Edad , Neoplasias/patología , Neoplasias/virología , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Neoplasias Gástricas/virología
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