RESUMEN
High-quality oxygen isotope analysis of composition-variable minerals (e.g., ubiquitous carbonates) using secondary ion mass spectrometry (SIMS) is extremely challenging. The classical off-line procedure, which requires additional electron probe microanalyzer (EPMA) chemical compositions for calibrating instrumental mass fractionation (IMF), is inherently inaccurate and analytically inefficient. In this study, the first accurate and paired SIMS analysis of δ18O and Fe# [molar Fe/(Mg + Fe)] in dolomite is reported. Based on five newly developed dolomite O-isotopic standards with an Fe# range of 0.01-0.35 obtained by SIMS, a novel accurate and rapid online matrix effect calibration method for dolomite O-isotope analysis was developed using concurrent SIMS 18O-16O-56Fe16O-24Mg16O measurements without additional chemical electron probe microanalysis. A logistic equation was proposed as the best-fit curve to represent the δ18O matrix effect based on the 56Fe16O/24Mg16O ratios. For CTD-4 carbonatitic dolomite with variable Fe# but homogeneous oxygen isotopes, the off-line method exhibited highly variable apparent δ18O values in the range of 5.74-10.11. The online method yielded a homogeneous δ18O value of 7.94 ± 0.34 (2SD, n = 40), which is comparable with that of bulk analysis (7.94 ± 0.20; 2SD). Comprehensive analyses validated the online method as the best strategy for performing accurate δ18O analysis of samples with highly heterogeneous compositions. Based on its accuracy, simplicity, and economic feasibility, this method has potential applications in the analysis of composition-complex dolomites, detrital dolomites, and other precious terrestrial and extraterrestrial materials.
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Carbonato de Calcio , Minerales , Carbonato de Calcio/química , Calibración , Magnesio , Isótopos de Oxígeno/químicaRESUMEN
Lignan is the main medicinal component of Eucommia ulmoides, and lignin is involved in the defense of plants against diseases and insect pests.They are synthesized from coniferyl alcohol with the help of dirigent(DIR) and peroxidase(POD), respectively.In this study, transcriptome assembly of stems and leaves of E.ulmoides was performed, yielding 112 578 unigenes.Among them, 70 459 were annotated in seven databases.A total of 59 unigenes encodes 11 key enzymes in the biosynthesis pathways of lignin and lignin, of which 11 encode POD and 8 encode DIR.A total of 13 unigenes encoding transcription factors are involved in phenylpropanoid metabolism. Compared with leaves of E.ulmoides, 7 575 unigenes were more highly expressed in stems, of which 462 were involved in phenylpropanoid biosynthesis.Our results extend the public transcriptome dataset of E.ulmoides, which provide valuable information for the analysis of biosynthesis pathways of lignan and lignin in E.ulmoides and lay a foundation for further study on the functions and regulation mechanism of key enzymes in lignan and lignin biosynthesis pathways.
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Eucommiaceae , Lignanos , Vías Biosintéticas , Eucommiaceae/genética , Lignanos/metabolismo , Lignina/metabolismo , TranscriptomaRESUMEN
CONTEXT: Amblyopia is an ophthalmological developmental disorder that occurs during early childhood due to disrupted binocular vision. It leads to reduced best-corrected visual acuity in one eye (seldom in both eyes) in which the visual acuity of one eye is 2 rows weaker than the other eye on a Snellen vision testing chart. Many studies have reported the outcomes of acupuncture in the treatment of amblyopia. Evidence suggests that acupuncture improves outcomes in children with amblyopia, but these studies are associated with several limitations which may affect the evaluation of the efficacy and reproducibility of studies on acupuncture. One important limitation is the lack of sham acupuncture as a control which has not been used in any clinical trial. The use of nonacupoint acupuncture is suggested as a placebo to improve the quality of evidence and comparability?
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Terapia por Acupuntura , Ambliopía , Ambliopía/terapia , Niño , Preescolar , Humanos , Reproducibilidad de los Resultados , Visión Binocular , Agudeza VisualRESUMEN
Oxygen isotope ratios in mantle-derived magmas that differ from typical mantle values are generally attributed to crustal contamination, deeply subducted crustal material in the mantle source or primordial heterogeneities. Here we provide an alternative view for the origin of light oxygen-isotope signatures in mantle-derived magmas using kimberlites, carbonate-rich magmas that assimilate mantle debris during ascent. Olivine grains in kimberlites are commonly zoned between a mantle-derived core and a magmatic rim, thus constraining the compositions of both mantle wall-rocks and melt phase. Secondary ion mass spectrometry (SIMS) analyses of olivine in worldwide kimberlites show a remarkable correlation between mean oxygen-isotope compositions of cores and rims from mantle-like 18O/16O to lower 'crustal' values. This observation indicates that kimberlites entraining low-18O/16O olivine xenocrysts are modified by assimilation of low-18O/16O sub-continental lithospheric mantle material. Interaction with geochemically-enriched domains of the sub-continental lithospheric mantle can therefore be an important source of apparently 'crustal' signatures in mantle-derived magmas.
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OBJECTIVE: To study the clinicopathologic characteristics of metaplastic thymoma. METHODS: Resection specimens of 3 cases of metaplastic thymoma were studied by light microscopy, immunohistochemistry and electron microscopy. RESULTS: All the 3 patients were females and aged 33, 58 and 45 years respectively. Histologically, a biphasic growth pattern, consisting of intimate admixture of epithelial cells and spindle cells, was noted. The epithelial cells showed mild cytologic atypia, sometimes nuclear grooves and pseudonuclear cytoplasmic inclusions. These cells were arranged in nests and anastomosing cords. Mitotic figures were rarely seen. On the other hand, the spindle cells were bland-looking, mitotically inactive and arranged in fascicles. Immunohistochemical study showed that the epithelial cells strongly expressed cytokeratin (AE1/AE3) but not vimentin or CD5. The proliferation index, as demonstrated by Ki-67 immunostaining, was about 3% to 5%. In contrast, the spindle cells were diffusely positive for vimentin and epithelial membrane antigen. Staining for CD5 and CD20 was negative. The background lymphocytes were positive for CD3, but not for TdT and CD99. Ultrastructurally, well-formed desmosomes or hemidesmosomes were identified in the epithelial element. They were not detected within the spindle cells. CONCLUSION: Metaplastic thymoma is a rarely encountered indolent or low-grade thymic tumor and may represent a distinct clinicopathologic entity.
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Queratinas/metabolismo , Timoma/patología , Neoplasias del Timo/patología , Adulto , Antígenos CD5/metabolismo , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Mediastino/patología , Microscopía Electrónica , Persona de Mediana Edad , Timoma/metabolismo , Timoma/ultraestructura , Neoplasias del Timo/metabolismo , Neoplasias del Timo/ultraestructura , Vimentina/metabolismoRESUMEN
OBJECTIVE: To explore one of evidence for pathologic diagnosis of early myocardial ischaemia. METHODS: Rats were ligated of the left coronary artery according to a previously documented technique, and heart tissue was sampled at different ischaemia time. The expression of CX43 in myocardial cell was detected by Immunohistochemistry. RESULTS: It is showed that the distribution and amount of CX43 positive staining in each group of the myocardial ischaemia was different from that of the control group. CONCLUSION: The changes of CX43 detected by Immunohistochemical methods may be helpful for the diagnosis of early myocardial ischaemia, but further pathologic investigation and research is necessary.
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Conexina 43/metabolismo , Isquemia Miocárdica/metabolismo , Miocitos Cardíacos/metabolismo , Miometrio/patología , Animales , Modelos Animales de Enfermedad , Femenino , Patologia Forense , Inmunohistoquímica , Masculino , Isquemia Miocárdica/patología , Miometrio/metabolismo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Coloración y Etiquetado , Factores de Tiempo , Distribución TisularRESUMEN
OBJECTIVE: To describe the fine needle aspiration cytology (FNAC) features of various salivary gland lesions and to analyze the respective diagnostic value and pitfalls. METHODS: 113 FNAC specimens of salivary gland lesions were reviewed and correlated with clinical and histopathologic findings. RESULTS: The FNAC diagnostic failure (2); non-neoplastic lesions (12); benign neoplasm (82) and malignant neoplasm (17). Cytologically, the distinction between cellular pleomorphic adenoma, adenoid cystic carcinoma and basal cell adenoma could be difficult due to their overlapping morphologic features. The cytologic patterns of primary lymphoepithelial carcinoma of the parotid were indistinguishable from those of metastatic nasopharyngeal undifferentiated carcinoma. The ultimate distinction relied on clinical correlation. The three inaccurately diagnosed cases of FNAC are, as follows: reactive lymphoid hyperplasia of lymph node mistaken as non-Hodgkin lymphoma, mucoepidermoid carcinoma diagnosed as "scanty atypical cells present" and primary lymphoepithelial carcinoma mistaken as benign lymphoepithelial lesion. On the basis of FNAC, 97.4% (110 /113) were correctly depicted as benign (95/96; 99.0%) or malignant (15/17; 88.2%). Furthermore, 90.3% (102 /113) (specificity = 91.9%; 102/111) were accurately diagnosed, including 91.7% (88/96) benign lesions (specificity = 92.6% ; 88/95) and 82.4% (14/17) malignant tumors (specificity = 87.5%; 14/16). CONCLUSIONS: FNAC is reliable in distinguishing benign and malignant salivary gland lesions. A specific cytologic diagnosis is often possible. On the other hand, due to the pitfalls in cytologic diagnosis of certain salivary gland tumors, tissue biopsy for histologic examination may be necessary.
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Carcinoma Mucoepidermoide/patología , Carcinoma de Células Escamosas/patología , Neoplasias de las Glándulas Salivales/patología , Glándulas Salivales/patología , Adenolinfoma/patología , Adenoma/patología , Adenoma Pleomórfico/patología , Adolescente , Adulto , Anciano , Biopsia con Aguja Fina , Carcinoma Adenoide Quístico/patología , Niño , Diagnóstico Diferencial , Errores Diagnósticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Parótida/patología , Estudios Retrospectivos , Neoplasias de la Glándula Submandibular/patologíaRESUMEN
OBJECTIVE: To study the expressions of matrix metalloproteinase 2 (MMP2) and E-cadherin (E-CD) in salivary mucoepidermoid carcinoma, and their relationship with clinical stages, pathological grading, lymph node metastasis and prognosis. METHODS: Surgical specimens of salivary mucoepidermiod carcinoma and normal salivary gland tissue were collected. MMP-2 and E-CD were stained immunohistochemically with streptavidin peroxidase method. RESULTS: The expression of MMP-2 was increased and the expression of E-CD was reduced or negative in salivary mucoepidemoid carcinoma compared with those of the normal salivary gland. Expression of MMP-2 and E-CD was closely correlated with lymph node metastasis of the mucoepidermoid carcinoma. MMP-2 was positively correlated with the prognosis of mucoepidermoid carcinoma, and E-CD was negatively correlated to the prognosis of mucoepidermoid carcinoma. CONCLUSION: The expression of MMP-2 and E-CD is closely correlated with the metastasis and prognosis of salivary mucoepidermoid carcinoma.
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Cadherinas/biosíntesis , Carcinoma Mucoepidermoide/metabolismo , Metaloproteinasa 2 de la Matriz/biosíntesis , Neoplasias de las Glándulas Salivales/metabolismo , Cadherinas/genética , Carcinoma Mucoepidermoide/patología , Humanos , Metaloproteinasa 2 de la Matriz/genética , Invasividad Neoplásica , Metástasis de la Neoplasia , Pronóstico , Neoplasias de las Glándulas Salivales/patologíaRESUMEN
PURPOSE: To investigate the relationship between expression of cell cycle-related protein cyclin D1, p27kip1 and the pathogenesis of bronchioloalveolar carcinoma (BAC) and the value of prediction of prognosis. METHODS: Cyclin D1 and p27kip1 protein were detected by immunohistochemical En Vision method in 43 BACs. RESULTS: The positivity of cyclin D1 in BAC was 65.1% (28/43), which was significantly higher than that in normal pulmonary tissue (0/13), P<0.01. No statistically significant association was found between cyclin D1 expression data and sex, age, tobacco-use history, histologic subtype (mucinous vs nonmucinous), stromal fibrosis, lymph node metastasis, clinical stage or postoperative survival period (P>0.05), while cyclin D1 expression was found to be negatively correlated with tumor size (P<0.05). The positivity of p27kip1 in BACs was 51.2% (22/43), significantly lower than that in normal pulmonary tissue (12/13), P<0.01. p27kip1 expression level was not associated with sex, age, tobacco-use history, tumor size or histologic subtype (P>0.05), but was negatively correlated with stromal fibrosis, lymph node metastasis and clinical stage (P<0.05); and positively associated with postoperative survival period (P<0.01). The survival rate of p27kip1 positive group was significantly higher than that of p27kip1 negative group (P<0.01). No statistically significant correlation was found between cyclin D1 and p27kip1 expression. CONCLUSIONS: Increased cyclin D1 expression and decreased p27kip1 expression are related to the pathogenesis of BAC; decreased p27kip1 expression is associated with metastasis progression; immunodetection of p27kip1 is useful for assessment of prognosis.