Current status and advances in diagnosis and treatment of solid pseudopapillary neoplasm of the pancreas / 中华消化外科杂志

Solid pseudopapillary neoplasm of the pancreas (SPN) is a rare pancreatic tumor with low-grade malignancy. Surgical resection is the preferred therapeutic approach for SPN patients, which has favourable prognosis with extremely low incidence of recurrence and metastasis and 5-year survival rate as 95%. With the improvement of radiological and pathological diagnosis, the detection rate of SPN is increasing. However, its pathogenesis is still unclear. Meanwhile, the diagnostic criteria and treatment strategies of SPN require standardization. Herein, the authors review the current status and advances in SPN based on related literature and clinical experience of the authors′ team on treatment of SPN, in order to deepen the knowledge of SPN, improve the ability for the preoperative diagnosis, promote standardized treatment and maximize benefits of the patients.

Species sensitivity analysis of heavy metals to freshwater organisms.

Acute toxicity data of six heavy metals [Cu, Hg, Cd, Cr(VI), Pb, Zn] to aquatic organisms were collected and screened. Species sensitivity distributions (SSD) curves of vertebrate and invertebrate were constructed by log-logistic model separately. The comprehensive comparisons of the sensitivities of different trophic species to six typical heavy metals were performed. The results indicated invertebrate taxa to each heavy metal exhibited higher sensitivity than vertebrates. However, with respect to the same taxa species, Cu had the most adverse effect on vertebrate, followed by Hg, Cd, Zn and Cr. When datasets from all species were included, Cu and Hg were still more toxic than the others. In particular, the toxicities of Pb to vertebrate and fish were complicated as the SSD curves of Pb intersected with those of other heavy metals, while the SSD curves of Pb constructed by total species no longer crossed with others. The hazardous concentrations for 5 % of the species (HC5) affected were derived to determine the concentration protecting 95 % of species. The HC5 values of the six heavy metals were in the descending order: Zn > Pb > Cr > Cd > Hg > Cu, indicating toxicities in opposite order. Moreover, potential affected fractions were calculated to assess the ecological risks of different heavy metals at certain concentrations of the selected heavy metals. Evaluations of sensitivities of the species at various trophic levels and toxicity analysis of heavy metals are necessary prior to derivation of water quality criteria and the further environmental protection.