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Gymnosphaera represents a minor lineage within the scaly tree‐fern family Cyatheaceae. Tropical and subtropical mainland Asia is a main distribution area of Gymnosphaera. However, the species diversity of Gymnosphaera is currently incompletely known in mainland Asia due to lacking critical revision. Here we present new findings of species diversity and their relationships to mainland Asian Gymnosphaera based on field surveys, the examination of herbarium collections, and phylogenetic analyses of sequences of multiple chloroplast and nuclear regions. Two new species, G. saxicola from southwestern Yunnan and G. bachmaensis from central Vietnam, are established. Traditionally recognized G. podophylla is revealed to be a complex, from which G. bonii is reinstated as a distinct species. Our phylogenetic analyses identified four clades within Gymnosphaera in mainland Asia: G. denticulata clade, G. gigantea clade, G. podophylla clade, and G. salletii clade. The new species G. saxicola, which is special for its saxicolous habitat, was resolved as sister to G. austroyunnanensis in the G. salletii clade. The newly discovered G. bachmaensis, which is characterized specially by the spathulate frond, was positioned in the G. podophylla clade, being sister to G. bonii. The mountainous region from south‐central Vietnam northwards to western Yunnan is a diverse center of Gymnosphaera and more species of this group are probably to be discovered there. [ABSTRACT FROM AUTHOR]

Background: Treating perihilar cholangiocarcinoma (PHCC) is particularly difficult due to the fact that it is usually in an advanced stage at the time of diagnosis. Irreversible electroporation treatment (IRE) involves the local administration of a high-voltage electric current to target lesions without causing damage to surrounding structures. This study investigated the safety and efficacy of using IRE in conjunction with intraoperative biliary stent placement in cases of unresectable PHCC. Methods: This study enrolled 17 patients with unresectable Bismuth type III/IV PHCC who underwent IRE in conjunction with intraoperative biliary stent placement (laparotomic) in two medical centers in Asia between June 2015 and July 2018. Analysis focused on the perioperative clinical course, the efficacy of biliary decompression, and outcomes (survival). Results: Mean total serum bilirubin levels (mg/dL) on postoperative day (POD) 7, POD30, and POD90 were significantly lower than before IRE (respectively 3.46 vs 4.54, p=0.007; 1.21 vs 4.54, p<0.001; 1.99 vs 4.54, p<0.001). Mean serum carbohydrate antigen 19-9 (CA19-9, U/ml) levels were significantly higher on POD3 than before the operation (518.8 vs 372.4, p=0.001) and significantly lower on POD30 and POD90 (respectively 113.7 vs 372.4, p<0.001; 63.9 vs 372.4, p<0.001). No cases of Clavien-Dindo grade III/IV adverse events or mortality occurred within 90 days post-op. The median progression-free survival was 21.5 months, and the median overall survival was 27.9 months. All individuals who survived for at least one year did so without the need to carry percutaneous biliary drainage (PTBD) tubes. Conclusions: It appears that IRE treatment in conjunction with intraoperative biliary stent placement is a safe and effective approach to treating unresectable PHCC. The decompression of biliary obstruction without the need for PTBD tubes is also expected to improve the quality of life of patients. [ABSTRACT FROM AUTHOR]

Irreversible electroporation (IRE) is a modality that utilizes high electric voltage to cause cell apoptosis. IRE has been used to treat locally advanced pancreatic cancer (LAPC). However, studies of IRE via surgical approaches for LAPC are limited. This study aims to analyse the outcomes and related prognostic factors of IRE for Asian patients with LAPC. From 2012 to 2017, this prospective trial for using IRE through surgical approaches for LAPC was conducted in 11 medical centres in Asia. All related and treatment outcomes were analysed from a prospective database. Seventy-four patients were enrolled. Thirty complications occurred in thirteen (17.6%) patients without mortality. The electrode placement direction (anteroposterior vs. craniocaudal, HR = 14.2, p < 0.01) and gastrointestinal invasion (HR = 15.7, p < 0.01) were significant factors for complications. The progression-free survival (PFS) rate in one year, three years, and five years were 69.1%, 48.7%, and 28.8%, and the overall survival (OS) rate in one year, three years, and five years were 97.2%, 53%, and 31.2%. In univariate analysis, the chemotherapy regimen, local tumour recurrence, axial tumour length, tumour volume, and serum carbohydrate antigen 19-9 levels were all significantly associated with PFS and OS. In multivariate analysis, the chemotherapy regimen was the only significant factor associated with PFS and OS. TS-1 (Tegafur, gimeracil, and oteracil) group has superior survival outcome than gemcitabine group. This study showed that combined induction chemotherapy and surgical IRE for LAPC is safe. For well-selected patients, IRE can achieve encouraging survival outcomes. [ABSTRACT FROM AUTHOR]

Aim Fossil-based biome reconstructions predict that during the Last Glacial Maximum ( LGM), the subtropical zone of East Asia was reduced to a narrow southern belt. In contrast, previous phylogeographical studies of subtropical plant species, many of which are rare, indicated different glacial refugia north of this predicted area. Here, we aim to elucidate the phylogeographical structure and putative refugia of Castanopsis eyrei, a widely distributed tree of subtropical evergreen broad-leaved forests of China. Location Subtropical China. Methods We compiled distribution data and employed climate envelope model projections to predict potential areas at the LGM. Microsatellite data and chloroplast DNA (cp DNA) sequence data were obtained for 31 populations sampled throughout the species' range. Microsatellites were analysed with Bayesian clustering. Relationships among cp DNA haplotypes were depicted in a statistical parsimony network. We analysed patterns of variation within and among populations and clusters and along latitudinal clines. Results Modelling revealed a potential LGM distribution of C. eyrei in a broad but interrupted belt overlapping the southern part of the present range. Nuclear microsatellites revealed two main clusters, suggesting a split between the western and eastern range, and a south-to-north decline in genetic variation. The eastern cluster harboured significantly higher nuclear genetic diversity. Sixteen closely related cp DNA haplotypes were identified. Populations were strongly differentiated at cp DNA markers, but lacked phylogeographical structure. Both data sets revealed higher genetic differentiation in the western cluster than in the eastern cluster. Main conclusions Our results suggest at least two putative refugia during the LGM, further refugia-within-refugia substructure and a post-glacial northwards recolonization. Topographical differences between the mountainous western and the lowland eastern refugia may have affected the patterns of genetic differentiation between the extant populations. Incongruence between nuclear and chloroplast data might be attributed to ancestral polymorphism of cp DNA and chloroplast capture, but does not contradict the hypothesis of multiple refugia. Our results are likely to represent a template for evolutionary history and phylogeography in this region. [ABSTRACT FROM AUTHOR]