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CHIP (Carboxy terminus of Hsc70 Interacting Protein) is an E3 ubiquitin ligase that can induce ubiquitination and degradation of several oncogenic proteins. The expression of CHIP is frequently lower in human breast cancer than in normal breast tissue. However, the expression and role of CHIP in the canine mammary gland tumor (CMGT) remain unclear. We investigated the potential correlation between CHIP expression and mammary gland tumor prognosis in female dogs. CHIP expression was measured in 54 dogs by immunohistochemistry and real-time RT-PCR. CHIP protein expression was significantly correlated with the histopathological diagnosis, outcome of disease and tumor classification. The transcriptional level of CHIP was significantly higher in normal tissues (P=0.001) and benign tumors (P=0.009) than it in malignant tumors. CHIP protein expression was significantly correlated with the transcriptional level of CHIP (P=0.0102). The log-rank test survival curves indicated that patients with low expression of CHIP had shorter overall periods of survival than those with higher CHIP protein expression (P=0.050). Our data suggest that CHIP may play an important role in the formation and development of CMGTs and serve as a valuable prognostic marker and potential target for genetic therapy. [ABSTRACT FROM AUTHOR]

The Yulong porphyry Cu (Au) deposit occurs on the eastern margin of the Tibetan plateau and is one of the largest porphyry Cu (Au) deposits in China, containing more than 6 million tons of Cu metal. Similar to other porplayry Cu deposits in the world, the Yulong porphyry is highly oxidized. Sulfate is the dominant sulfur species in fluid inclusions hosted by magmatic quartz phenocrysts, and no sulfide is observed, indicating an oxygen fugacity above the SSO buffer during magmatic processes. The sulfur species changed from sulfate dominant during magmatic processes to sulfide dominant during the main mineralization processes, with sulfate and sulfide mineral assemblages observed in fluid inclusions in mineralized quartz veinlets and only sulfides in the orebodies, corresponding to a decrease in redox potential from the porphyry to the hydrothermal fluid. Magnetite crystallization was coincident with the onset of major sulfate reduction, indicating that magnetite isolated trivalent iron, reducing sulfate, and consequently leading to the formation of porphyry Cu-Au mineralization. Most porphyry Cu-Au ore deposits are spatially associated with, and genetically related to, oxidized felsic magmas. Our results indicate that sulfate reduction promoted by magnetite crystallization is essential for the final precipitation of Cu-Au-bearing sulfides, i.e., decreasing redox potential of the fluid is the key to, and direct cause of, ore formation in Yulong. Initial high redox potential is a prerequisite for and may be an indirect indicator of most mineralization of this kind, because it enables efficient transportation of Cu-Au. Redox potential fluctuations can be well preserved in zircon, a resistant accessory mineral commonly found in porphyries, which might be developed as a handy and reliable exploration tool for porphyry Cu deposits associated with magnetite. [ABSTRACT FROM AUTHOR]

The Lower Yangtze river belt is one of the most important metallogenic belts ha China. The mechanisms responsible for ore genesis and the formation of related Cretaceous igneous rocks, such as adakite, A-type granitoid, and Nb-enriched basalt, remain controversial. Mesozoic granitoids in the Lower Yangtze river belt were mostly formed in the Early Cretaceous (140-125 Ma), and three granitoid belts--the inner, the south, and the north--have been defined according to petrological and geochemical characteristics. Previously, based mainly on negative εNd and high initial Sr isotope values, the adakitic rocks were generally attributed "to partial melting of thickened or delaminated lower crust, both of which require crustal thickening. Mesozoic crustal thickening, however, is not supported by the development of extensional basins in the region. From the Late Jurassic to Cretaceous, eastern China was closely associated with subduction of the Pacific plate in the south and the Izanagi plate in the north. The midocean ridge (MOR) between these two plates was drifting toward and likely subducting under the Lower Yangtze river belt. A ridge subduction model can therefore explain the distribution of different magmatic rocks and ore deposits in the belt. Partial melting of subducting young, hot oceanic slabs close to the ridge formed adakitic rocks. The negative εNd values of adakitic rocks can be plausibly interpreted by mixing between adakitic magmas and enriched components in the lithospheric mantle, and/or crustal materials through AFC process. A slab window opened during ridge subduction as indicated by A-type granitoids in the center of the inner belt. Nb-enriched basalt found in the belt was likely formed by partial melting of a mantle wedge metasomatized by fluids released from the subducting slab at shallow depth. [ABSTRACT FROM AUTHOR]

The BRCA1 gene plays an important role in the development of human breast cancer, and recent research indicated that genetic variations of BRCA1 are also related to canine mammary tumors (CMTs). Here, using rapid amplification of cDNA ends (RACE), we cloned the 5'- and 3'-UTRs of BRCA1. By direct sequencing of the flanking sequences of the 5'- and 3'-UTRs of BRCA1, three previously unreported single-nucleotide polymorphisms (SNPs) were identified, two (-1228T >C, -1173C >T) in the putative promoter regions and one non-synonymous SNP (63449G >A) in exon 23. Compared with 16 normal samples, the sequences from 34 CMTs suggested that SNP (-1173C >T) was associated with the development of CMTs (odds ratio (OR)=2.57, 95% confidence interval (CI): 1.07-6.15). [ABSTRACT FROM AUTHOR]

Presents osmium-osmium dating results of copper and molybdenum deposits along the middle and lower reaches of the Yangtze River, China. Relationship between mineralization and the emplacement of the ore-associated intrusive rocks; Geologic setting and sample locations; Information on longshusan copper-gold-molybdenum vein deposit.