The concept of uncertainty in an isotopic analysis is not uniform in the scientific community worldwide and can compromise the risk of false compliance assessment applied to carbon isotopic analyses in natural gas exploratory evaluation. In this work, we demonstrated a way to calculate one of the main sources of this uncertainty, which is underestimated in most studies focusing on gas analysis: the δC calculation itself is primarily based on the raw analytical data. The carbon isotopic composition of methane, ethane, propane, and CO was measured.
View Article and Find Full Text PDFPhacomatosis pigmentovascularis is a rare syndrome, defined as the simultaneous presence of vascular nevus and melanocytic nevus in the same patient. We report the case of a 53-year-old woman presented with dermal melanosis and extensive vascular nevus, which match the typical manifestations of phakomatosis pigmetovascularis of cesioflammea type, according to Happle's classification. The rare occurrence of this genodermatosis and the clinical exuberance of the skin lesions motivated this case report.
View Article and Find Full Text PDFLucio's phenomenon represents a serious cutaneous necrotizing reaction, which can occur with Lucio's leprosy and also in other forms of lepromatous leprosy. The authors discuss the case of a 63-year-old male patient presenting with ulcers and necrotic cutaneous lesions on the limbs, torso and face, associated with recurring sinusitis, hoarseness and a weight loss of 25 kilos over the last year. Bacilloscopy of intradermal scrapings showed a bacilloscopic index of 5 and the histopathological findings were compatible with the diagnosis of Lucio's phenomenon.
View Article and Find Full Text PDFCutaneous endometriosis is a rare manifestation of endometriosis, representing 0.5% to 1% of all endometriosis cases. It can be divided into primary and secondary, when appearing spontaneously or after a surgical procedure, when it is mostly found on surgical scar tissue.
View Article and Find Full Text PDFAcanthosis nigricans is a common dermatosis and is most often associated with benign conditions, such as insulin resistance. It is rare as a paraneoplastic marker. As such, it is characterized by sudden onset and rapid dissemination of velvety and hyperchromic skin lesions.
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