Can low-dose intravenous bevacizumab be as effective as high-dose bevacizumab for cerebral radiation necrosis?

Although intravenous bevacizumab (IVBEV) is the most promising treatment for cerebral radiation necrosis (CRN), there is no conclusion on the optimal dosage. Our retrospective study aimed to compare the efficacy and safety of high-dose with low-dose IVBEV in treating CRN associated with radiotherapy for brain metastases (BMs). This paper describes 75 patients who were diagnosed with CRN secondary to radiotherapy for BMs, treated with low-dose or high-dose IVBEV and followed up for a minimum of 6 months. The clinical data collected for this study include changes in brain MRI, clinical symptoms, and corticosteroid usage before, during, and after IVBEV treatment. At the 3-month mark following administration of IVBEV, a comparison of two groups revealed that the median percentage decreases in CRN volume on T2-weighted fluid-attenuated inversion recovery and T1-weighted gadolinium contrast-enhanced image (T1CE), as well as the signal ratio reduction on T1CE, were 65.8% versus 64.8% (p = 0.860), 41.2% versus 51.9% (p = 0.396), and 37.4% versus 35.1% (p = 0.271), respectively. Similarly, at 6 months post-IVBEV, the median percentage reductions of the aforementioned parameters were 59.5% versus 62.0% (p = 0.757), 39.1% versus 31.3% (p = 0.851), and 35.4% versus 28.2% (p = 0.083), respectively. Notably, the incidence of grade ≥3 adverse events was higher in the high-dose group (n = 4, 9.8%) than in the low-dose group (n = 0). Among patients with CRN secondary to radiotherapy for BMs, the administration of high-dose IVBEV did not demonstrate superiority over low-dose IVBEV. Moreover, the use of high-dose IVBEV was associated with a higher incidence of grade ≥3 adverse events compared with low-dose IVBEV.

Risk-adapted stereotactic body radiotherapy for patients with cervical spinal metastases.

Owing to the complex anatomical structure and biomechanics, the current standard palliative treatments for cervical spinal metastases are associated with a high risk of recurrence and complications. Stereotactic body radiotherapy (SBRT) can provide radical dose to tumors while protecting normal organs to the maximum extent. However, the efficacy and safety of SBRT for cervical spinal metastases is not well characterized. Data from 71 patients with cervical spine metastases who were treated with SBRT using CyberKnife between 2006 and 2021 were obtained from our prospectively maintained database. Primary endpoint was pain response at 12 weeks following SBRT completion; secondary endpoints included local control (LC), overall survival (OS), and adverse events. Standard-risk patients were planned to receive 30 Gy (range 21-36) with median fractions of 3 (range 1-3) and high-risk patients 35 Gy (range 24-50) with median fractions of 5 (range 4-5) according to the spinal cord and esophagus dose constraints. The median follow-up time was 17.07 months (range 3.1-118.9). After 12 weeks of SBRT completion, 54 (98.2%) of 55 patients with baseline pain achieved pain response and 46 (83.6%) achieved complete pain response. LC rates were 93.1% and 90% at 1 year and 2 year, respectively. The 1-year and 2-year OS rates were 66.2% and 37.4%, respectively. Eight patients experienced grades 1-4 adverse events (six vertebral compression fracture [VCF], five of them had VCF before SBRT; and two hemiparesis). No grade 5 adverse events were observed. Therefore, risk-adapted SBRT for cervical spine metastases achieved high pain control and LC rates with acceptable adverse events.

Multi-locus genetic analyses of Quasipaa from throughout its distribution.

Montane frogs of the genus Quasipaa Dubois, 1992 occur from southern China to Southeast Asia (Frost 2021). Analyses of mtDNA (Cytb) and nuDNA data (Rag1, Rag2, Rhod, Tyr) for samples from 93 localities throughout its distribution yield a phylogeny. Clades A and B occur in Southeast Asia, clade C in northern Yangtze River, China, clade D in southwestern China, and clades E and F in southeastern China. Results place Q. yei within monophyletic Quasipaa and identify two new species. Based on nuDNA data, the basal split of clade A and B indicates an Indochinese origin of Quasipaa. The west-east diversification of five species across South China (Q. spinosa, Q. exilispinosa, Q. jiulongensis, Q. shini, Q. boulengeri) corresponds to topographic terrains II and III of China. Divergence of species from southeastern China (Q. shini, Q. jiulongensis, Q. spinosa, Q. exilispinosa) and southwestern China (Q. boulengeri) dates to 15.30-16.56 Ma (million years ago). A principal component analysis (PCA) and t-test involving 19 bioclimatic variables identifies significantly different environmental conditions between the two regions. Species' distribution models (SDM) for Q. spinosa and Q. boulengeri identify the best areas to be eastern and western South China, respectively. Thus, environmental variation appears to have influenced the genetic divergence and distributions of Quasipaa in South China. Mito-nuclear discordance indicates that some individuals of Q. exilispinosa and Q. spinosa hybridized historically.

An integrative phylogenomic approach illuminates the evolutionary history of Old World tree frogs (Anura: Rhacophoridae).

Rhacophoridae are one of the most speciose and ecologically diverse families of amphibians. Resolution of their evolutionary relationships is key to understanding the accumulation of biodiversity, yet previous hypotheses based on Sanger sequencing exhibit much discordance amongst generic relationships. This conflict precludes the making of sound macroevolutionary conclusions. Herein, we conduct the first phylogenomic study using broad-scale sampling and sequences of 352 nuclear DNA loci obtained using anchored hybrid enrichment targeted sequencing. The robust time-calibrated phylogenetic hypothesis clarifies several long-disputed relationships and facilitates the testing of evolutionary hypotheses on spatiotemporal diversification and reproductive modes. The major extant lineages of Rhacophoridae appear to have radiated in mainland Asia, and the spatiotemporal process corresponds with several common accumulations of biodiversity in Asia. Analyses do not detect any case of "Out of Himalaya" in Rhacophoridae. All transitions of reproductive modes appear to have evolved in an ordered, gradual sequence associated with gaining independence of standing water for larval development. The different reproductive modes are phylogenetically conserved and the completion of their transitions appear to have occurred over a period of ~30 Ma, which does not fit a pattern of a rapid burst of diversification. Innovations in reproductive modes associate statistically with the uneven distribution of species-richness between clades, where higher diversification is linked to increased terrestrial modes of reproduction. These results strengthen the hypothesis that breeding innovations drive diversification by providing new opportunities for ecological release and dispersion.

Risk-based, response-adapted therapy for early-stage extranodal nasal-type NK/T-cell lymphoma in the modern chemotherapy era: A China Lymphoma Collaborative Group study.

We aimed to determine the survival benefits of chemotherapy (CT) added to radiotherapy (RT) in different risk groups of patients with early-stage extranodal nasal-type NK/T-cell lymphoma (ENKTCL), and to investigate the risk of postponing RT based on induction CT responses. A total of 1360 patients who received RT with or without new-regimen CT from 20 institutions were retrospectively reviewed. The patients had received RT alone, RT followed by CT (RT + CT), or CT followed by RT (CT + RT). The patients were stratified into different risk groups using the nomogram-revised risk index (NRI). A comparative study was performed using propensity score-matched (PSM) analysis. Adding new-regimen CT to RT (vs RT alone) significantly improved overall survival (OS, 73.2% vs 60.9%, P < .001) and progression-free survival (PFS, 63.5% vs 54.2%, P < .001) for intermediate-risk/high-risk patients, but not for low-risk patients. For intermediate-risk/high-risk patients, RT + CT and CT + RT resulted in non-significantly different OS (77.7% vs 72.4%; P = .290) and PFS (67.1% vs 63.1%; P = .592). For patients with complete response (CR) after induction CT, initiation of RT within or beyond three cycles of CT resulted in similar OS (78.2% vs 81.7%, P = .915) and PFS (68.2% vs 69.9%, P = .519). For patients without CR, early RT resulted in better PFS (63.4% vs 47.6%, P = .019) than late RT. Risk-based, response-adapted therapy involving early RT combined with CT is a viable, effective strategy for intermediate-risk/high-risk early-stage patients with ENKTCL in the modern treatment era.

Risk-adapted stereotactic body radiation therapy for central and ultra-central early-stage inoperable non-small cell lung cancer.

To determine the therapeutic efficacy and safety of risk-adapted stereotactic body radiation therapy (SBRT) schedules for patients with early-stage central and ultra-central inoperable non-small cell lung cancer. From 2006 to 2015, 80 inoperable T1-2N0M0 NSCLC patients were treated with two median dose levels: 60 Gy in six fractions (range, 48-60 Gy in 4-8 fractions) prescribed to the 74% isodose line (range, 58%-79%) for central lesions (ie within 2 cm of, but not abutting, the proximal bronchial tree; n = 43), and 56 Gy in seven fractions (range, 48-60 Gy in 5-10 fractions) prescribed to the 74% isodose line (range, 60%-80%) for ultra-central lesions (ie abutting the proximal bronchial tree; n = 37) on consecutive days. Primary endpoint was overall survival (OS); secondary endpoints included progression-free survival (PFS), tumor local control rate (LC), and toxicity. Median OS and PFS were 64.47 and 32.10 months (respectively) for ultra-central patients, and not reached for central patients. Median time to local failure, regional failure, and any distant failures for central versus ultra-central lesions were: 27.37 versus 26.07 months, 20.90 versus 12.53 months, and 20.85 versus 15.53 months, respectively, all P < .05. Multivariate analyses showed that tumor categorization (ultra-central) and planning target volume ≥52.76 mL were poor prognostic factors of OS, PFS, and LC, respectively (all P < .05). There was one grade 5 toxicity; all other toxicities were grade 1-2. Our results showed that ultra-central tumors have a poor OS, PFS, and LC compared with central patients because of the use of risk-adapted SBRT schedules that allow for equal and favorable toxicity profiles.

Large-scale phylogenetic analyses provide insights into unrecognized diversity and historical biogeography of Asian leaf-litter frogs, genus Leptolalax (Anura: Megophryidae).

Southeast Asia and southern China (SEA-SC) harbor a highly diverse and endemic flora and fauna that is under increasing threat. An understanding of the biogeographical history and drivers of this diversity is lacking, especially in some of the most diverse and threatened groups. The Asian leaf-litter frog genus Leptolalax Dubois 1980 is a forest-dependent genus distributed throughout SEA-SC, making it an ideal study group to examine specific biogeographic hypotheses. In addition, the diversity of this genus remains poorly understood, and the phylogenetic relationships among species of Leptolalax and closely related Leptobrachella Smith 1928 remain unclear. Herein, we evaluate species-level diversity based on 48 of the 53 described species from throughout the distribution of Leptolalax. Molecular analyses reveal many undescribed species, mostly in southern China and Indochina. Our well-resolved phylogeny based on multiple nuclear DNA markers shows that Leptolalax is not monophyletic with respect to Leptobrachella and, thus, we assign the former to being a junior synonym of the latter. Similarly, analyses reject monophyly of the two subgenera of Leptolalax. The diversification pattern of the group is complex, involving a high degree of sympatry and prevalence of microendemic species. Northern Sundaland (Borneo) and eastern Indochina (Vietnam) appear to have played pivotal roles as geographical centers of diversification, and paleoclimatic changes and tectonic movements seem to have driven the major divergence of clades. Analyses fail to reject an "upstream" colonization hypothesis, and, thus, the genus appears to have originated in Sundaland and then colonized mainland Asia. Our results reveal that both vicariance and dispersal are responsible for current distribution patterns in the genus.

A novel multilocus phylogenetic estimation reveals unrecognized diversity in Asian horned toads, genus Megophrys sensu lato (Anura: Megophryidae).

The horned toad assemblage, genus Megophrys sensu lato, currently includes three groups previously recognized as the genera Atympanophrys, Xenophrys and Megophrys sensu stricto. The taxonomic status and species composition of the three groups remain controversial due to conflicting phenotypic analyses and insufficient phylogenetic reconstruction; likewise, the position of the monotypic Borneophrys remains uncertain with respect to the horned toads. Further, the diversity of the horned toads remains poorly understood, especially for widespread species. Herein, we evaluate species-level diversity based on 45 of the 57 described species from throughout southern China, Southeast Asia and the Himalayas using Bayesian inference trees and the Generalized Mixed Yule Coalescent (GMYC) approach. We estimate the phylogeny using both mitochondrial and nuclear DNA data. Analyses reveal statistically significant mito-nuclear discordance. All analyses resolve paraphyly for horned toads involving multiple strongly supported clades. These clades correspond with geography. We resurrect the genera Atympanophrys and Xenophrys from the synonymy of Megophrys to eliminate paraphyly of Megophrys s.l. and to account for the morphological, molecular and biogeographic differences among these groups, but we also provide an alternative option. Our study suggests that Borneophrys is junior synonym of Megophrys sensu stricto. We provide an estimation of timeframe for the horned toads. The mitochondrial and nuclear trees indicate the presence of many putative undescribed species. Widespread species, such as Xenophrys major and X. minor, likely have dramatically underestimated diversity. The integration of morphological and molecular evidence can validate this discovery. Montane forest dynamics appear to play a significant role in driving diversification of horned toads.

Risk-adapted therapy for early-stage extranodal nasal-type NK/T-cell lymphoma: analysis from a multicenter study.

The optimal combination and sequence of radiotherapy (RT) and chemotherapy (CT) for extranodal nasal-type natural killer/T-cell lymphoma (NKTCL) are not well-defined. The aim of this study was to create a risk-adapted therapeutic strategy for early-stage NKTCL. A total of 1273 early-stage patients from 10 institutions were reviewed. Patients received CT alone (n = 170), RT alone (n = 253), RT followed by CT (n = 209), or CT followed by RT (n = 641). A comprehensive comparative study was performed using multivariable and propensity score-matched analyses. Early-stage NKTCL was classified as low risk or high risk based on 5 independent prognostic factors (stage, age, performance status, lactate dehydrogenase, primary tumor invasion). RT alone and RT with or without CT were more effective than CT alone (5-year overall survival [OS], 69.6% and 67.7% vs 33.9%, P < .001). For low-risk patients, RT alone achieved a favorable OS (88.8%); incorporation of induction or consolidation CT did not provide additional benefit (86.9% and 86.3%). For high-risk patients, RT followed by CT resulted in superior OS (72.2%) compared with induction CT and RT (58.3%, P = .004) or RT alone (59.6%, P = .017). After adjustment, similar significant differences in OS were still observed between treatment groups. New CT regimens provided limited benefit in early-stage NKTCL. Risk-adapted therapy involving RT alone for low-risk patients and RT consolidated by CT for high-risk patients is a viable, effective strategy for early-stage NKTCL.

Spatiotemporal Diversification of the True Frogs (Genus Rana): A Historical Framework for a Widely Studied Group of Model Organisms.

True frogs of the genus Rana are widely used as model organisms in studies of development, genetics, physiology, ecology, behavior, and evolution. Comparative studies among the more than 100 species of Rana rely on an understanding of the evolutionary history and patterns of diversification of the group. We estimate a well-resolved, time-calibrated phylogeny from sequences of six nuclear and three mitochondrial loci sampled from most species of Rana, and use that phylogeny to clarify the group's diversification and global biogeography. Our analyses consistently support an "Out of Asia" pattern with two independent dispersals of Rana from East Asia to North America via Beringian land bridges. The more species-rich lineage of New World Rana appears to have experienced a rapid radiation following its colonization of the New World, especially with its expansion into montane and tropical areas of Mexico, Central America, and South America. In contrast, Old World Rana exhibit different trajectories of diversification; diversification in the Old World began very slowly and later underwent a distinct increase in speciation rate around 29-18 Ma. Net diversification is associated with environmental changes and especially intensive tectonic movements along the Asian margin from the Oligocene to early Miocene. Our phylogeny further suggests that previous classifications were misled by morphological homoplasy and plesiomorphic color patterns, as well as a reliance primarily on mitochondrial genes. We provide a phylogenetic taxonomy based on analyses of multiple nuclear and mitochondrial gene loci. [Amphibians; biogeography; diversification rate; Holarctic; transcontinental dispersal.

Pericytes: a double-edged sword in cancer therapy.

Pericytes, which envelope the vascular endothelium throughout the body, are often targeted to promote vascular normalization and restore normal function of blood vessels in cancer treatment. The goals of pericyte-targeted therapy tend to promote proper vascular normalization of the tumor. Tumor vascular normalization prevents metastasis, increases tumor oxygenation (making radiation more effective in killing tumor cells), optimizes Starling forces to increase delivery of cancer cell-directed therapies (e.g., chemotherapy or targeted agents), increases the efficacy of focal therapies (e.g., surgery or radiation), and increases recognition by the host immune system. We review how approaches in pericyte-targeted therapy aim to reach a balance between pro-angiogenic and anti-angiogenic function (i.e., by targeting platelet-derived growth factor beta receptors, vascular endothelial growth factor receptors and Tie-2) for tumor vascular normalization.

Similar Outcomes of Standard Radiotherapy and Hypofractionated Radiotherapy Following Breast-Conserving Surgery.

BACKGROUND: Adjuvant radiation therapy is commonly administered to breast cancer patients who received breast-conserving surgery. However, lengthy treatment times of standard radiotherapy pose certain challenges. Here, we performed a prospective controlled study comparing standard radiation to hypofractionated radiotherapy in terms of efficacy and outcome. MATERIAL AND METHODS: Eighty breast cancer patients (tumor stage pT1-2N0-1M0) who had undergone breast-conservation surgery were randomly divided into 2 groups (40 patients/group). The experimental group received 43.2 Gy to the whole breast in 18 fractions for 24 days with a concomitant boost (50.4 Gy) to the tumor bed. The control group received 45 Gy to the whole breast in 25 fractions for 44 days with a boost to the tumor bed of 59 Gy. Survival, locoregional recurrence, adverse effects, and aesthetic results were all considered for analysis. RESULTS: The following criteria were included as part of study follow-up: local control, survival, adverse skin reactions, cosmetic outcome, and hematological toxicity. At a median follow-up of 27 months (follow-up rate 100%), there were no statistical differences in any of the categories between the 2 groups. The 2-year survival rate of both groups was 100% without any locoregional recurrence. Although there was some skin toxicity, these instances were not severe and they cleared on their own within 6 weeks. The most common problems encountered by patients were breast fibrosis and altered pigmentation. CONCLUSIONS: A shortened whole-breast hypofractionated irradiation schedule with a concomitant boost is as effective as standard radiation and may be a reasonable alternative following breast conservation surgery.

Experimental study on the regulation of erlotinib-induced radiosensitization with an anti-c-MET monoclonal antibody.

PURPOSE: Erlotinib is a novel therapeutic agent for cancer treatment. This study was performed to investigate the role of c-MET-PI3K-AKT pathway in the regulation of erlotinib-induced radiosensitization. METHODS: A973 lung adenocarcinoma cells treated with 6 Gy of radiation were incubated in the presence of erlotinib. The apoptotic rate after 24 hours, the colony-formating rate after 14 days, and changes in the c-MET expression levels after 14 days of irradiation were examined. Surviving fractions in different treatment groups (blank control, radiation alone, erlotinib alone, anti-c-MET monoclonal antibody alone, combined erlotinib and radiation, and combined erlotinib and radiation with anti-c-MET monoclonal antibody groups) were determined, the survival curves were plotted, and the sensitizer enhancement ratio was calculated using colony formation assays. Expressions of c-MET, p-c-MET, PI3K, AKT, and p-AKT in cells in different treatment groups were examined by Western blot analysis. RESULTS: The apoptotic rate in the combined erlotinib and radiation group was higher than those in single treatment groups; however, the colony-forming rate remained approximately 2.04 ± 1.02%. The expression of c-MET in colony-forming cells in the combined group significantly increased, and the blockade of c-MET activity significantly enhanced the radiosensitizing effect of erlotinib. The expression of c-Met, p-c-MET, PI3K, AKT, and p-AKT among colony-forming cells significantly decreased upon the inhibition of c-MET. CONCLUSIONS: Upregulated activity of the c-MET-PI3K-AKT pathway was found to be important for cell survival under combined the treatment with erlotinib and radiation. The blockade of the c-MET-PI3K-AKT signaling pathway enhanced the radiosensitizing effect of erlotinib.

Dosimetric analysis of brachial plexopathy after stereotactic body radiotherapy: Significance of organ delineation.

OBJECTIVES: Examine the significance of contouring the brachial plexus (BP) for toxicity estimation and select metrics for predicting radiation-induced brachial plexopathy (RIBP) after stereotactic body radiotherapy. MATERIALS AND METHODS: Patients with planning target volume (PTV) ≤ 2 cm from the BP were eligible. The BP was contoured primarily according to the RTOG 1106 atlas, while subclavian-axillary veins (SAV) were contoured according to RTOG 0236. Apical PTVs were classified as anterior (PTV-A) or posterior (PTV-B) PTVs. Variables predicting grade 2 or higher RIBP (RIBP2) were selected through least absolute shrinkage and selection operator regression and logistic regression. RESULTS: Among 137 patients with 140 BPs (median follow-up, 32.1 months), 11 experienced RIBP2. For patients with RIBP2, the maximum physical dose to the BP (BP-Dmax) was 46.5 Gy (median; range, 35.7 to 60.7 Gy). Of these patients, 54.5 % (6/11) satisfied the RTOG limits when using SAV delineation; among them, 83.3 % (5/6) had PTV-B. For patients with PTV-B, the maximum physical dose to SAV (SAV-Dmax) was 11.2 Gy (median) lower than BP-Dmax. Maximum and 0.3 cc biologically effective doses to the BP based on the linear-quadratic-linear model (BP-BEDmax LQL and BP-BED0.3cc LQL, α/ß = 3) were selected as predictive variables with thresholds of 118 and 73 Gy, respectively. CONCLUSION: Contouring SAV may significantly underestimate the RIBP2 risk in dosimetry, especially for patients with PTV-B. BP contouring indicated BP-BED0.3cc LQL and BP-BEDmax LQL as potential predictors of RIBP2.

Brachial plexopathy following stereotactic body radiation therapy in apical lung malignancies: A dosimetric pooled analysis of individual patient data.

BACKGROUND AND OBJECTIVES: The aim of this study is to establish dosimetric constraints for the brachial plexus at risk of developing grade ≥ 2 brachial plexopathy in the context of stereotactic body radiation therapy (SBRT). PATIENTS AND METHODS: Individual patient data from 349 patients with 356 apical lung malignancies who underwent SBRT were extracted from 5 articles. The anatomical brachial plexus was delineated following the guidelines provided in the atlases developed by Hall, et al. and Kong, et al.. Patient characteristics, pertinent SBRT dosimetric parameters, and brachial plexopathy grades (according to CTCAE 4.0 or 5.0) were obtained. Normal tissue complication probability (NTCP) models were used to estimate the risk of developing grade ≥ 2 brachial plexopathy through maximum likelihood parameter fitting. RESULTS: The prescription dose/fractionation schedules for SBRT ranged from 27 to 60 Gy in 1 to 8 fractions. During a follow-up period spanning from 6 to 113 months, 22 patients (6.3 %) developed grade ≥2 brachial plexopathy (4.3 % grade 2, 2.0 % grade 3); the median time to symptoms onset after SBRT was 8 months (ranged, 3-54 months). NTCP models estimated a 10 % risk of grade ≥2 brachial plexopathy with an anatomic brachial plexus maximum dose (Dmax) of 20.7 Gy, 34.2 Gy, and 42.7 Gy in one, three, and five fractions, respectively. Similarly, the NTCP model estimates the risks of grade ≥2 brachial plexopathy as 10 % for BED Dmax at 192.3 Gy and EQD2 Dmax at 115.4 Gy with an α/ß ratio of 3, respectively. Symptom persisted after treatment in nearly half of patients diagnosed with grade ≥2 brachial plexopathy (11/22, 50 %). CONCLUSIONS: This study establishes dosimetric constraints ranging from 20.7 to 42.7 Gy across 1-5 fractions, aimed at mitigating the risk of developing grade ≥2 brachial plexopathy following SBRT. These findings provide valuable guidance for future ablative SBRT in apical lung malignancies.

Erratum: Abnormal spindle-like microcephaly-associated protein (ASPM) contributes to the progression of Lung Squamous Cell Carcinoma (LSCC) by regulating CDK4: Erratum.

[This corrects the article DOI: 10.7150/jca.39760.].

First national record of Microhylahmongorum Hoang, Nguyen, Phan, Pham, Ninh, Wang, Jiang, Ziegler and Nguyen, 2022 (Anura, Microhylidae, Microhyla) in China.

Background: To date, 10 species of the genus Microhyla have been recorded in China, of which six were distributed in Yunnan Province. Microhylahmongorum Hoang, Nguyen, Phan, Pham, Ninh, Wang, Jiang, Ziegler, and Nguyen, 2022 was also speculated to be distributed in Xishuangbana, Yunnan Province, China. However, there is no evidence of documentation of M.hmongorum. New information: We report the first country record of Microhylahmongorum, based on specimens collected from Yunnan border region. Morphologically, the specimen was consistent with the original descriptions of M.hmongorum. Phylogenetically, the sequences of the specimens from China clustered with the sequence of type specimens of M.hmongorum from Vietnam, with uncorrected pairwise distances of 0.9% at the 16S gene fragment analysed. Therefore, we report M.hmongorum as a new record species in China.

DNA barcoding of Chinese snakes reveals hidden diversity and conservation needs.

DNA barcoding has greatly facilitated studies of taxonomy, biodiversity, biological conservation, and ecology. Here, we establish a reliable DNA barcoding library for Chinese snakes, unveiling hidden diversity with implications for taxonomy, and provide a standardized tool for conservation management. Our comprehensive study includes 1638 cytochrome c oxidase subunit I (COI) sequences from Chinese snakes that correspond to 17 families, 65 genera, 228 named species (80.6% of named species) and 36 candidate species. A barcode gap analysis reveals gaps, where all nearest neighbour distances exceed maximum intraspecific distances, in 217 named species and all candidate species. Three species-delimitation methods (ABGD, sGMYC, and sPTP) recover 320 operational taxonomic units (OTUs), of which 192 OTUs correspond to named and candidate species. Twenty-eight other named species share OTUs, such as Azemiops feae and A. kharini, Gloydius halys, G. shedaoensis, and G. intermedius, and Bungarus multicinctus and B. candidus, representing inconsistencies most probably caused by imperfect taxonomy, recent and rapid speciation, weak taxonomic signal, introgressive hybridization, and/or inadequate phylogenetic signal. In contrast, 43 species and candidate species assign to two or more OTUs due to having large intraspecific distances. If most OTUs detected in this study reflect valid species, including the 36 candidate species, then 30% more species would exist than are currently recognized. Several OTU divergences associate with known biogeographic barriers, such as the Taiwan Strait. In addition to facilitating future studies, this reliable and relatively comprehensive reference database will play an important role in the future monitoring, conservation, and management of Chinese snakes.

Comparative multi-locus assessment of modern Asian newts ( Cynops, Paramesotriton, and Pachytriton: Salamandridae) in southern China suggests a shared biogeographic history.

Evolutionary biologists are always interested in deciphering the geographic context of diversification, therefore they introduced the concept of comparative phylogeography, which helps to identify common mechanisms that contribute to shared genetic structures among organisms from the same region. Here, we used multi-locus genetic data along with environmental data to investigate shared phylogeographic patterns among three Asian-endemic newt genera, Cynops, Paramesotriton and Pachytriton, which occurred in montane/submontane streams or ponds in southern China. Our 222 samples from 78 localities covered the entire range of the three genera and represented the largest dataset of this group to date. We reconstructed matrilineal genealogies from two protein-coding, mitochondrial genes, and gene network from two nuclear genes. We also estimated divergence times of major cladogenetic events and used occurrence data to evaluate niche difference and similarity between lineages. Our results revealed a common basal split in all three genera that corresponds to the separation of two geographic terrains of southern China. Those ancient divergence occurred during middle to late Miocene and likely correlate with paleoclimatic fluctuations caused by the uplift of the Qinghai-Xizang (Tibet) Plateau (QTP). Particularly, the strengthening and weakening of Asian summer monsoons during the Miocene may have profoundly impacted southern China and led to repeatedly vicariance in those newts. However, despite differences in realized niches between lineages, there is no evidence for divergence of fundamental niches. Preservation of old newt matriline lineages in mountains of southern China suggests that the region acts as both museums and cradles of speciation. Based on those results, we advocate a multi-pronged protection strategy for newts in the three genera.