RESUMO
Chemotherapy drugs are mainly administered via intravenous injection or oral administration in a very a high dosage. If there is a targeted drug vehicle which can be deployed on the tumor, the medical treatment is specific and precise. Binary mixing of biocompatible Pluronic® F127 and Pluronic® L121 was used in this study for a drug carrier of pluronic biomedical hydrogels (PBHs). Based on the same PBH ingredients, the addition of fluorouracil (5-FU) was separated in three ways when it was incorporated with pluronics: F127-L121-(5-FU), F127-(5-FU), and L121-(5-FU). Small angle X-ray scattering experiments were performed to uncover the self-assembled structures of the PBHs. Meanwhile, the expected micelle and lamellar structural changes affected by the distribution of 5-FU were discussed with respect to the corresponding drug release monitoring. PBH-all with the mixing method of F127-L121-(5-FU) has the fastest drug release rate owing to the undulated amphiphilic boundary. In contrast, PBH-2 with the mixing method of L121-(5-FU) has a prolonged drug release rate at 67% for one month of the continuous drug release experiment because the flat lamellar amphiphilic boundary of PBH-2 drags the migration of 5-FU from the hydrophobic core. Therefore, the PBHs developed in the study possess great potential for targeted delivery and successfully served as a microenvironment model to elucidate the diffusion pathway of 5-FU.
RESUMO
Wax gourd (Benincasa hispida) is a popular cucurbitaceous summer crop used for culinary purposes, confectionery, and refreshing drinks in Asia. During a field survey for cucurbit viral diseases at Beidou, Changhua in May 2017, B. hispida plants with symptoms of mosaic, chlorosis and leaf curl were found. Because more than 90% of plants showed leaf curl symptoms, samples were first examined by PCR with degenerate primers for begomoviruses (Forward: 5'-TGTGAAGGNCCDTGTAARGT-3' and Reverse: 5'-GCRTDGGTACADGCCATATA-3'). Sequence analysis of amplicons revealed that all of tested plants were infected by squash leaf curl Philippine virus (SqLCPhV) (Liao et al., 2007). However, electron microscopic examination revealed potyvirus-like particles and pinwheel-like inclusion bodies on some of begomovirus-infected leaves showing mild curling and mosaic symptoms. RT-PCR with potyvirusdegenerate primers (PNIbF1: 5'-GGBAAYAATAGTGGNCAACC-3' and PCPR1: 5'-GGGGAGGTGCCGTTCTCDATRCACC-3') were used to detect the potyvirus. Among 8 samples examined, all were infected by SqLCPhV (100%) and 5 samples were mixed infection of SqLCPhV and a potyvirus (62.5%). The filamentous virus was isolated from field samples by sap inoculating plants of B. hispida to separate from nonmechanically-transmissible SqLCPhV. Inoculated B. hispida plants showed severe mosaic and deformation. Total RNA was extracted from inoculated B. hispida and used for RT-PCR with a degenerate potyvirus primer PNIbF1 (5'- GGBAAYAATAGTGGNCAACC) pairing with oligo-dT. A 1.8-kb DNA fragment containing partial NIb gene, full-length coat protein (CP) gene, and 3'-UTR was amplified, cloned, and sequenced. The CP gene (293 aa) shared 82.1% nucleotide and 81% amino acid sequence identity to that of zucchini tigre mosaic virus (ZTMV) isolate E11045 (KC345608). Two degenerate primers (fZTMV-F: 5'- AGCRTGTGGYAHCC-3' and gourd-R: 5'-TCCCACCAYTTYTCRAAHGT-3') target the flanking region between the middle of P3 and 5' of CIP genes of ZTMV strains were designed and used to detect ZTMV. An expected 0.7 kb fragment could be amplified from 2 of 5 field-collected samples and all 6 mechanically inoculated B. hispida plants. Upon sap inoculation, ZTMV was also able to infect pumpkin (Cucurbita pepo var. pepo), zucchini (C. pepo var. cylindrica), squash (C. moschata), bottle gourd (Lagenaria siceraria) and Cucumis metuliferus, but not bitter gourd (Momordica charantia), cucumber (Cucumis sativus), watermelon (Citrullus lanatus), luffa (Luffa cylindrica), tobacco (including Nicotiana benthamiana, N. tabacum, and N. glutinoa), Chenopdium quinoa and C. amaranticolor. The infection of ZTMV to all mechanically inoculated plants were tested by RT-PCR using the fZTMV-F and gourd-R primers and/or TEM examinations. To the best of our knowledge, this is the first report of ZTMV infecting B. hispida in Taiwan. ZTMV was originally reported as a T strain of papaya ringspot virus (PRSV-T) (Quiot-Doine et al., 1986), and was later reclassified as a distinct species in the genus Potyvirus (Romay et al., 2014).
RESUMO
Southern rice black-streaked dwarf virus (SRBSDV), which causes severe disease symptoms in rice (Oriza sativa L.) has been emerging in the last decade throughout northern Vietnam, southern Japan and southern, central and eastern China. Here we attempt to quantify the prevalence of SRBSDV in the Honghe Hani rice terraces system (HHRTS)-a Chinese 1300-year-old traditional rice production system. We first confirm that genetically diverse rice varieties are still being cultivated in the HHRTS and categorize these varieties into three main genetic clusters, including the modern hybrid varieties group (MH), the Hongyang improved modern variety group (HY) and the traditional indica landraces group (TIL). We also show over a 2-year period that SRBSDV remains prevalent in the HHRTS (20.1% prevalence) and that both the TIL (17.9% prevalence) and the MH varieties (5.1% prevalence) were less affected by SRBSDV than were the HY varieties (30.2% prevalence). Collectively we suggest that SRBSDV isolates are freely moving within the HHRTS and that TIL, HY and MH rice genetic clusters are not being preferentially infected by particular SRBSDV lineages. Given that SRBSDV can cause 30-50% rice yield losses, our study emphasizes both the need to better monitor the disease in the HHRTS, and the need to start considering ways to reduce its burden on rice production.
