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2.
Nature ; 480(7377): 348-50, 2011 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-22170681

RESUMEN

Type Ia supernovae are thought to result from a thermonuclear explosion of an accreting white dwarf in a binary system, but little is known of the precise nature of the companion star and the physical properties of the progenitor system. There are two classes of models: double-degenerate (involving two white dwarfs in a close binary system) and single-degenerate models. In the latter, the primary white dwarf accretes material from a secondary companion until conditions are such that carbon ignites, at a mass of 1.38 times the mass of the Sun. The type Ia supernova SN 2011fe was recently detected in a nearby galaxy. Here we report an analysis of archival images of the location of SN 2011fe. The luminosity of the progenitor system (especially the companion star) is 10-100 times fainter than previous limits on other type Ia supernova progenitor systems, allowing us to rule out luminous red giants and almost all helium stars as the mass-donating companion to the exploding white dwarf.

3.
J Transl Med ; 11: 29, 2013 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-23369209

RESUMEN

BACKGROUND: Colorectal carcinomas spread easily to nearby tissues around the colon or rectum, and display strong potential for invasion and metastasis. CSE1L, the chromosome segregation 1-like protein, is implicated in cancer progression and is located in both the cytoplasm and nuclei of tumor cells. We investigated the prognostic significance of cytoplasmic vs. nuclear CSE1L expression in colorectal cancer. METHODS: The invasion- and metastasis-stimulating activities of CSE1L were studied by in vitro invasion and animal experiments. CSE1L expression in colorectal cancer was assayed by immunohistochemistry, with tissue microarray consisting of 128 surgically resected specimens; and scored using a semiquantitative method. The correlations between CSE1L expression and clinicopathological parameters were analyzed. RESULTS: CSE1L overexpression was associated with increased invasiveness and metastasis of cancer cells. Non-neoplastic colorectal glands showed minimal CSE1L staining, whereas most colorectal carcinomas (99.2%, 127/128) were significantly positive for CSE1L staining. Cytoplasmic CSE1L was associated with cancer stage (P=0.003) and depth of tumor penetration (P=0.007). Cytoplasmic CSE1L expression also correlated with lymph node metastasis of the disease in Cox regression analysis CONCLUSIONS: CSE1L regulates the invasiveness and metastasis of cancer cells, and immunohistochemical analysis of cytoplasmic CSE1L in colorectal tumors may provide a useful aid to prognosis.


Asunto(s)
Proteína de Susceptibilidad a Apoptosis Celular/metabolismo , Neoplasias Colorrectales/metabolismo , Citoplasma/metabolismo , Invasividad Neoplásica , Adulto , Anciano , Anciano de 80 o más Años , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/patología , Femenino , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Análisis de Matrices Tisulares
4.
J Am Assoc Lab Anim Sci ; 62(4): 327-335, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37758477

RESUMEN

Hypochlorous acid (HOCl), used as a liquid or a fog, has broad antimicrobial and deodorizing effects. Our facility was the first in Taiwan that was built with a system to supply stabilized, biosafe HOCl solution (50 ppm available chlorine concentration, pH 6) into a new animal barrier facility that housed genetically modified mice. The HOCl system creates an extremely clean environment that allows us to raise mice in static, filter-top cages and to handle them on open tables without the need for biologic safety cabinets (BSC). Our animal facility (AF) sometimes receives mice from outside sources that are infected with pathogens, notably murine norovirus (MNV), Helicobacter spp., and trichomonads. We found that our standard operation procedure (SOP) prevented cross-contamination to other mice, including those in adjacent cages. After the removal of infected mice from a room, the remaining mice remained uninfected, without the need for extensive environmental decontamination. Learning this allowed us to use a test-and-removal method to eliminate pathogens. In addition, infected mouse strains that were not commercially available were rederived by using cross-fostering. After finding unexpected infections, we were able to identify all infected mice by widespread screening. We then removed contaminated cages and performed cross-fostering as needed. This approach was able to successfully eliminate murine norovirus, Helicobacter spp., and trichomonads. Over the 12 y in which we managed this AF, we refined our husbandry methods and our approach to the detection and eradication of pathogens by using HOCl fog and solution, the test-and-removal, and cross-fostering.


Asunto(s)
Infecciones por Caliciviridae , Norovirus , Animales , Ratones , Ácido Hipocloroso , Infecciones por Caliciviridae/prevención & control , Infecciones por Caliciviridae/veterinaria , Vivienda para Animales , Crianza de Animales Domésticos/métodos
5.
J Speech Lang Hear Res ; 64(4): 1176-1188, 2021 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-33789056

RESUMEN

Purpose This study explored the neural marker indexing deficits in discriminating lexical tone changes in Mandarin-speaking children with developmental language disorders (DLDs) using mismatch negativity, an event-related potential component for auditory change detection. Mandarin has four lexical tones characterized by a high-level tone (T1), high-rising tone (T2), low-dipping tone (T3), and high-falling tone (T4), in which the T2/T3 contrast is acoustically less discriminable in developmental groups. Therefore, this study further examined how deficits in children with DLD would vary with tonal contrasts' acoustic saliency. Method Event-related potentials were measured using the multideviant oddball paradigm described by Lee et al. (2012), who used Mandarin syllables [i] in T3 as the standard sound (80%), T1 as the large deviant (10%), and T2 as the small deviant (10%). Twelve children with DLD aged between 4 and 6 years participated in this study, and 12 age-matched children with typical development were selected from the data set of Lee et al. (2012) as the controls. Results The T1/T3 change elicited adultlike mismatch negativity in both the DLD and control groups, while no group difference was revealed. The T2/T3 change elicited a robust positive mismatch response (P-MMR) in children with DLD, while the P-MMR was less significant in the control group. The group comparisons revealed a larger P-MMR in children with DLD than in the control group. Furthermore, children with lower scores in language assessments tend to reveal larger P-MMRs. Conclusions This study demonstrated that deficits in children with DLD in discriminating subtle lexical tone changes reflect greater positivity of P-MMR to T2/T3 change. This implies that MMR to T2/T3 may serve as a neural marker for evaluating language delay in preschoolers.


Asunto(s)
Trastornos del Desarrollo del Lenguaje , Percepción del Habla , Estimulación Acústica , Niño , Preescolar , Electroencefalografía , Potenciales Evocados , Humanos , Sonido
6.
Gen Comp Endocrinol ; 159(1): 16-25, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18713635

RESUMEN

Two full-length cDNA sequences encoding a crustacean hyperglycemic hormone (CHH) precursor were cloned from tissues of the mud crab Scylla olivacea. Sco-CHH (S. olivacea CHH) was cloned from eyestalk ganglia, whereas Sco-CHH-L (S. olivacea CHH-like peptide) was cloned from extra-eyestalk tissues (pericardial organ and thoracic ganglia). Each conceptually translated precursor is expected to be processed into a signal peptide, a CHH precursor-related peptide (CPRP), and a mature CHH or CHH-like peptide. The two precursors are identical in amino acid sequence through the 40th residue of the mature peptide, but different from each other substantially in the C-terminus. Both CHH variants contain the six highly conserved cysteine residues characteristic of the CHH family peptides, and share higher sequence identities with other brachyuran CHH sequences than with those of other taxonomic groups. As determined by reverse transcription-polymerase chain reaction (RT-PCR), the transcripts of Sco-CHH and Sco-CHH-L were present in eyestalk ganglia and several extra-eyestalk tissues (the thoracic ganglia, pericardial organ, brain, circumesophageal connectives, and gut). Sco-CHH was the predominant form in eyestalk ganglia, while Sco-CHH-L was the predominant form in several extra-eyestalk tissues. Neither transcript was expressed in the muscle, hepatopancreas, ovary, testis, heart, or gill. Antisera were raised against synthetic peptides corresponding to a stretch of sequence-specific to the C-terminus of Sco-CHH or Sco-CHH-L. Western blot analyses of tissues expressing Sco-CHH and Sco-CHH-L detected a Sco-CHH immunoreactive protein in the sinus gland, and a Sco-CHH-L immunoreactive protein in the pericardial organ. Immunohistochemical analyses of the eyestalk ganglia localized both Sco-CHH and Sco-CHH-L immunoreactivity to the sinus gland, and only Sco-CHH immunoreactivity to the X-organ somata; analyses of the pericardial organs also localized both Sco-CHH and Sco-CHH-L immunoreactivity to the anterior and posterior bars, as well as to longitudinal trunks joining the two bars. The combined data provided supporting evidence that Sco-CHH and Sco-CHH-L are co-localized in the same tissue.


Asunto(s)
Braquiuros/genética , Perfilación de la Expresión Génica , Proteínas del Tejido Nervioso/genética , Precursores de Proteínas/genética , Secuencia de Aminoácidos , Animales , Proteínas de Artrópodos , Secuencia de Bases , Western Blotting , Braquiuros/metabolismo , Clonación Molecular , ADN Complementario/genética , Electroforesis en Gel de Poliacrilamida , Femenino , Inmunohistoquímica , Hormonas de Invertebrados , Masculino , Datos de Secuencia Molecular , Músculos/metabolismo , Miocardio/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Ovario/metabolismo , Precursores de Proteínas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia , Testículo/metabolismo
7.
Int J Biol Markers ; 27(3): e280-4, 2012 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-22653741

RESUMEN

The chromosome segregation 1-like (CSE1L) protein is highly expressed in most cancers and has been shown to be secreted by tumor cells. We studied the presence of CSE1L in the urine of patients with bladder urothelial carcinomas. The results of our immunohistochemical analysis showed a high expression of CSE1L in bladder cancer specimens, while the normal bladder specimens only showed a very faint staining in some cells. Immunoblotting showed that CSE1L was present in urine of patients with bladder cancer. Urinary CSE1L-positive cases were detected in 95% (57/60) of patients with bladder urothelial carcinomas or the atypical/suspicious cases with urothelial atypia. No CSE1L was detected in urine of healthy controls (p<0.01). Our results suggest that urinary CSE1L deserves further evaluation for the screening of bladder cancer.


Asunto(s)
Biomarcadores de Tumor/orina , Carcinoma de Células Transicionales/orina , Proteína de Susceptibilidad a Apoptosis Celular/orina , Neoplasias de la Vejiga Urinaria/orina , Anciano , Anciano de 80 o más Años , Carcinoma de Células Transicionales/patología , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Neoplasias de la Vejiga Urinaria/patología
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