During plant-pathogen interactions, plants use intracellular proteins with nucleotide-binding site and Leu-rich repeat (NBS-LRR) domains to detect pathogens. NBS-LRR proteins represent a major class of plant disease resistance genes (-genes). Whereas -genes have been well characterized in angiosperms, little is known about their origin and early diversification. Here, we perform comprehensive evolutionary analyses of-genes in plants and report the identification of -genes in basal-branching streptophytes, including charophytes, liverworts, and mosses. Phylogenetic analyses suggest that plant-genes originated in charophytes and R-proteins diversified into TIR-NBS-LRR proteins and non-TIR-NBS-LRR proteins in charophytes. Moreover, we show that plant R-proteins evolved in a modular fashion through frequent gain or loss of protein domains. Most of the -genes in basal-branching streptophytes underwent adaptive evolution, indicating an ancient involvement of-genes in plant-pathogen interactions. Our findings provide novel insights into the origin and evolution of -genes and the mechanisms underlying colonization of terrestrial environments by plants.

The purpose of our study was to investigate the temporal malignant tumor incidence rates among the 70,000 residents at the relatively isolated Nanao Island in South China Sea. The data on all malignant tumor cases from Nanao Cancer Registry during 1995-2004 were coded, computerized, and analyzed using the software SPSS10.0. The tumor incident cases, crude incident rate, age-standardized incidence rate, their sex distribution and temporal trend were assessed. A total of 1450 new cancer cases (990 males and 460 females) were identified. The annual average age-standardized incidence rate (ASR) of malignant tumors was 208.18/100,000. The age-standardized incidence rate of the ten leading cancers in both sexes combined per 100,000 population were 74.47 for esophageal cancer (EC), 34.81 for cardiac cancer (CC), 25.66 for liver cancer, 26.01 for lung cancer, 18.52 for stomach cancer, 4.45 for nasopharyngeal cancer, 3.91 for breast cancer, 2.53 for colon/rectum cancer, 2.45 for bladder cancer and 1.92 for pancreatic cancer. These ten types of cancers make up to 93% of all cancer cases, with EC and CC being the most prevalent and making up 52% of the total cases. The incidence rates of esophagus, liver, lung, breast, nasopharyngeal, and colon/rectum cancers showed increasing trends during the period from 1995 to 2004 in Nanao Island. Astounding the EC ASR were 72-150/100,000 among male and 26-64/100,000 among female in Nanao Island during 1995-2004. The EC incidence rate in Nanao population is among the highest across the world, which suggests that there are potential genetic and/or environmental factors affecting this particular population.

Although a simple linear progression model for breast cancer has already been proposed, its validity still remains controversial. Especially, the genetic and molecular features of breast cancer at different stages during the development and progression, as well as their relationship, have rarely been studied under the same experimental conditions simultaneously. According to these limitations in this research area, the current study applied comparative genomic hybridization technique to investigate genomic changes in 15 cases of breast atypical ductal hyperplasia (ADH), 15 cases of ductal carcinomas in situ (DCIS), and 15 cases of invasive ductal carcinomas (IDC) and the relationship among the genetic changes. Thirty commonly altered regions that were identified included known (gains of 1q,8q, 17q,20q,Xq and losses of 8p,13q,16q,17p,22q) and several uncharacterized (gains of 2q,5p, 10p,12q,16p,18q, etc. and losses of 11p13-pter,11q,14q,Xp, etc). The overall frequency of copy number losses was higher in IDC than that in DCIS (P = 0.013). ADH showed more frequent gain of 17q than that in IDC (P = 0.007), and IDC exhibited a higher frequency for the loss of 22q than that in ADH (P = 0.018). On one hand, several common genomic changes shared by ADH, DCIS, and IDC make a linear relationship for these three lesions possible. On the other hand, the heterogeneity has also showed clonal diversification and different pathways of breast cancer progression. The regions of chromosomal copy number alterations may bring new insights into the strategy for tumor progression blocking and the discovery of new potential targets for breast cancer treatment.

Retention, a crucial process in pesticide application, is heavily affected by the extremely low surface energy and micro/nanostructure of plant leaves. The inadequate retention like bouncing, splashing, and drifting often give rise to severe soil and groundwater pollution. In this article, we present an unprecedented topology-regulation approach that significantly contributes to this issue. A series of pesticide-loaded “hat”-shaped Janus carriers (HJCs) are synthesized via emulsion interfacial polymerization and characterized by scanning electron microscope, thermogravimetric analyzer, energy-dispersive spectrometer, and Fourier transform infrared spectroscopy. Upon spraying on plant leaves, the pesticide-loaded HJCs can embed with the micropapillae and nanosplinters on leaves driven by the “hanger-hat” topology effect, consequently leading to the enhanced retention evaluated by the deposition and flush resistance experiments. Moreover, the release behavior of pesticide-loaded HJCs is found to match the Ritger-Peppas model and finally achieves sustained release. Additionally, the generality of the HJCs synthetic strategy is also studied and applicable to multiple pesticides. This study not only provides a new strategy for increasing pesticide retention on plant leaves but also opens a promising aspect for the applications of Janus carriers in agriculture.

Background and ObjectiveOesophageal cancer is one of the most common and deadliest cancers worldwide. Our previous population-based study reported a high prevalence of oesophageal cancer in Chaoshan, Guangdong Province, China. Ancestors of the Chaoshan population migrated from the Taihang Mountain region of north-central China, which is another high-incidence area for oesophageal cancer. The purpose of the present study was to obtain evidence of inherited susceptibility to oesophageal cancer in the Chaoshan population, with reference to the Taihang Mountain population, with the eventual goal of molecular identification of the disease genes.MethodsWe conducted familial correlation, commingling, and complex segregation analyses of 224 families from the Chaoshan population and 403 families from the Taihang population using the FPMM program of S.A.G.E. version 5.3.0. A second analysis focused on specific families having large numbers of affected individuals or early onset of the disease.ResultsFor the general population, moderate sib-sib correlation was noticed for esophageal cancer. Additionally, brother-brother correlation was even higher. Commingling analyses indicated that a three-component distribution model best accounts for the variation in age of onset of oesophageal cancer, and that a multifactorial model provides the best fit to the general population data. An autosomal dominant mode and a dominant or recessive major gene with polygenic inheritance were found to be the best models of inherited susceptibility to oesophageal cancer in some large families.ConclusionsThe current results provide evidence for inherited susceptibility to oesophageal cancer in certain high-risk groups in China, and support efforts to identify the susceptibility genes.

Pentacyclic triterpenoids, a class of naturally bioactive products having multiple functional groups, unique chiral centers, rigid skeletons, and good biocompatibility, are ideal building blocks for fabricating versatile supramolecular structures. In this research, the natural pentacyclic triterpenoid glycyrrhetinic acid (GA) was used as a guest molecule for β-cyclodextrin (β-CD) to form a GA/β-CD (1:1) inclusion complex. By means of GA and β-CD pendant groups in N,N'-dimethylacrylamide copolymers, a supramolecular polymer hydrogel can be physically cross-linked by host-guest interactions between GA and β-CD moieties. Moreover, self-healing of this hydrogel was observed and confirmed by step-strain rheological measurements, whereby the maximum storage modulus occurred at a [GA]/[β-CD] molar ratio of 1:1. Additionally, these polymers displayed outstanding biocompatibility. The introduction of a natural pentacyclic triterpenoid into a hydrogel system not only provides a biocompatible guest-host complementary GA/β-CD pair, but also makes this hydrogel an attractive candidate for tissue engineering.

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Injectable low-molecular-weight hydrogels (LMWHs) from biocompatible materials have attracted much attention in biomedical applications because they can adapt any desired sizes and cavity shapes. Searching for simple, biocompatible injectable LMWHs owning inherent antibacterial activity without complicated chemical modification remains an open question to avoid the tedious synthesis/purification process and the easy bacterial infection of hydrogels in a moist environment. In this work, glycyrrhizic acid (GL), a naturally occurring compound, was found to form a stable transparent LMWH at 37 °C in physiological phosphate buffered saline (PBS) with nanoclusters as the microstructures. Moreover, this hydrogel exhibited great injectable and moldable properties. The antibacterial study showed that the growth of Gram-positive Staphylococcus aureus (S. aureus) could be completely inhibited by GL, whereas noneffect on Gram-negative Escherichia coli (E. coli) was observed. In addition, cell viability and hemolysis assay revealed that GL had good biocompatibility and hemocompatibility to mammalian cells because of its natural origin. Our simple biocompatible injectable moldable LMWH with inherent antibacterial ability has potential in the area of biomaterials and 3D bioprinting.