Detection of transgene in early developmental stage by GFP monitoring enhances the efficiency of genetic transformation of pepper

In order to establish a reliable and highly efficient method for genetic transformation of pepper, a monitoring system featuring GFP (green fluorescent protein) as a report marker was applied to Agrobacterium-mediated transformation. A callus-induced transformation (CIT) system was used to transform the GFP gene. GFP expression was observed in all tissues of T0, T1 and T2 peppers, constituting the first instance in which the whole pepper plant has exhibited GFP fluorescence. A total of 38 T0 peppers were obtained from 4,200 explants. The transformation rate ranged from 0.47 to 1.83% depending on the genotype, which was higher than that obtained by CIT without the GFP monitoring system. This technique could enhance selection power by monitoring GFP expression at the early stage of callus in vitro. The detection of GFP expression in the callus led to successful identification of the shoot that contained the transgene. Thus, this technique saved lots of time and money for conducting the genetic transformation process of pepper. In addition, a co-transformation technique was applied to the target transgene, CaCS (encoding capsaicinoid synthetase of Capsicum) along with GFP. Paprika varieties were transformed by the CaCS::GFP construct, and GFP expression in callus tissues of paprika was monitored to select the right transformant

Excitability of Aβ sensory neurons is altered in an animal model of peripheral neuropathy

<p>Abstract</p> <p>Background</p> <p>Causes of neuropathic pain following nerve injury remain unclear, limiting the development of mechanism-based therapeutic approaches. Animal models have provided some directions, but little is known about the specific sensory neurons that undergo changes in such a way as to induce and maintain activation of sensory pain pathways. Our previous studies implicated changes in the Aβ, normally non-nociceptive neurons in activating spinal nociceptive neurons in a cuff-induced animal model of neuropathic pain and the present study was directed specifically at determining any change in excitability of these neurons. Thus, the present study aimed at recording intracellularly from Aβ-fiber dorsal root ganglion (DRG) neurons and determining excitability of the peripheral receptive field, of the cell body and of the dorsal roots.</p> <p>Methods</p> <p>A peripheral neuropathy was induced in Sprague Dawley rats by inserting two thin polyethylene cuffs around the right sciatic nerve. All animals were confirmed to exhibit tactile hypersensitivity to von Frey filaments three weeks later, before the acute electrophysiological experiments. Under stable intracellular recording conditions neurons were classified functionally on the basis of their response to natural activation of their peripheral receptive field. In addition, conduction velocity of the dorsal roots, configuration of the action potential and rate of adaptation to stimulation were also criteria for classification. Excitability was measured as the threshold to activation of the peripheral receptive field, the response to intracellular injection of depolarizing current into the soma and the response to electrical stimulation of the dorsal roots.</p> <p>Results</p> <p>In control animals mechanical thresholds of all neurons were within normal ranges. Aβ DRG neurons in neuropathic rats demonstrated a mean mechanical threshold to receptive field stimulation that were significantly lower than in control rats, a prolonged discharge following this stimulation, a decreased activation threshold and a greater response to depolarizing current injection into the soma, as well as a longer refractory interval and delayed response to paired pulse electrical stimulation of the dorsal roots.</p> <p>Conclusions</p> <p>The present study has demonstrated changes in functionally classified Aβ low threshold and high threshold DRG neurons in a nerve intact animal model of peripheral neuropathy that demonstrates nociceptive responses to normally innocuous cutaneous stimuli, much the same as is observed in humans with neuropathic pain. We demonstrate further that the peripheral receptive fields of these neurons are more excitable, as are the somata. However, the dorsal roots exhibit a decrease in excitability. Thus, if these neurons participate in neuropathic pain this differential change in excitability may have implications in the peripheral drive that induces central sensitization, at least in animal models of peripheral neuropathic pain, and Aβ sensory neurons may thus contribute to allodynia and spontaneous pain following peripheral nerve injury in humans.</p

Myc Prevents Apoptosis and Enhances Endoreduplication Induced by Paclitaxel

BACKGROUND: The role of the MYC oncogene in the apoptotic pathways is not fully understood. MYC has been reported to protect cells from apoptosis activation but also to sensitize cells to apoptotic stimuli. We have previously demonstrated that the down-regulation of Myc protein activates apoptosis in melanoma cells and increases the susceptibility of cells to various antitumoral treatments. Beyond the well-known role in the G1-->S transition, MYC is also involved in the G2-M cell cycle phases regulation. METHODOLOGY/PRINCIPAL FINDINGS: In this study we have investigated how MYC could influence cell survival signalling during G2 and M phases. We used the microtubules damaging agent paclitaxel (PTX), to arrest the cells in the M phase, in a p53 mutated melanoma cell line with modulated Myc level and activity. An overexpression of Myc protein is able to increase endoreduplication favoring the survival of cells exposed to antimitotic poisoning. The PTX-induced endoreduplication is associated in Myc overexpressing cells with a reduced expression of MAD2, essential component of the molecular core of the spindle assembly checkpoint (SAC), indicating an impairment of this checkpoint. In addition, for the first time we have localized Myc protein at the spindle poles (centrosomes) during pro-metaphase in different cell lines. CONCLUSIONS: The presence of Myc at the poles during the prometaphase could be necessary for the Myc-mediated attenuation of the SAC and the subsequent induction of endoreduplication. In addition, our data strongly suggest that the use of taxane in antitumor therapeutic strategies should be rationally based on the molecular profile of the individual tumor by specifically analyzing Myc expression levels

Segmental Duplications Arise from Pol32-Dependent Repair of Broken Forks through Two Alternative Replication-Based Mechanisms

The propensity of segmental duplications (SDs) to promote genomic instability is of increasing interest since their involvement in numerous human genomic diseases and cancers was revealed. However, the mechanism(s) responsible for their appearance remain mostly speculative. Here, we show that in budding yeast, replication accidents, which are most likely transformed into broken forks, play a causal role in the formation of SDs. The Pol32 subunit of the major replicative polymerase Polδ is required for all SD formation, demonstrating that SDs result from untimely DNA synthesis rather than from unequal crossing-over. Although Pol32 is known to be required for classical (Rad52-dependant) break-induced replication, only half of the SDs can be attributed to this mechanism. The remaining SDs are generated through a Rad52-independent mechanism of template switching between microsatellites or microhomologous sequences. This new mechanism, named microhomology/microsatellite-induced replication (MMIR), differs from all known DNA double-strand break repair pathways, as MMIR-mediated duplications still occur in the combined absence of homologous recombination, microhomology-mediated, and nonhomologous end joining machineries. The interplay between these two replication-based pathways explains important features of higher eukaryotic genomes, such as the strong, but not strict, association between SDs and transposable elements, as well as the frequent formation of oncogenic fusion genes generating protein innovations at SD junctions

Asian-Pacific consensus statement on the management of chronic hepatitis B: a 2008 update

Large amounts of new data on the natural history and treatment of chronic hepatitis B virus (HBV) infection have become available since 2005. These include long-term follow-up studies in large community-based cohorts or asymptomatic subjects with chronic HBV infection, further studies on the role of HBV genotype/naturally occurring HBV mutations, treatment of drug resistance and new therapies. In addition, Pegylated interferon α2a, entecavir and telbivudine have been approved globally. To update HBV management guidelines, relevant new data were reviewed and assessed by experts from the region, and the significance of the reported findings were discussed and debated. The earlier “Asian-Pacific consensus statement on the management of chronic hepatitis B” was revised accordingly. The key terms used in the statement were also defined. The new guidelines include general management, special indications for liver biopsy in patients with persistently normal alanine aminotransferase, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patients receiving immune-suppressive medications or chemotherapy and patients in the setting of liver transplantation, are also included

Evaluation of Collagen Dermal Filler with Lidocaine for the Correction of Nasolabial Folds: A Randomized, Double-Blind, Multicenter Clinical Trial

Chin-Yi Yang,1,2,&ast; Ya-Ching Chang,2,&ast; Hao-Chih Tai,3 Yi-Hua Liao,4 Yu-Huei Huang,2 Rosaline Chung-Yee Hui,2 Yuan-Sung Kuo,3 Shyue-Yih Horng,3 Yi-Shuan Sheen,4 Tim-Mo Chen,5 Yuan-Sheng Tzeng,5 Chih-Hsin Wang,5 Shou-Cheng Teng,5 Chun-Kai Oscar Chang,5 Chang-Yi Chou5 1Department of Dermatology, New Taipei Municipal TuCheng Hospital, New Taipei City, 236, Taiwan; 2Department of Dermatology, Linkou Chang-Gung Memorial Hospital, Taoyuan, 333, Taiwan; 3Department of Surgery, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, 100, Taiwan; 4Department of Dermatology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, 100, Taiwan; 5Division of Plastic Surgery, Tri-Service General Hospital, Taipei, 100, Taiwan&ast;These authors contributed equally to this workCorrespondence: Hao-Chih Tai, Department of Surgery, National Taiwan University Hospital and National Taiwan University College of Medicine, No. 7, Zhongshan S. Road, Zhongzheng Dist, Taipei, 100225, Taiwan, Tel +886 2 2312-3456&num;65062 65520, Email [email protected]; [email protected] Yi-Hua Liao, Department of Dermatology, National Taiwan University Hospital and National Taiwan University College of Medicine, No. 7, Zhongshan S. Road, Zhongzheng Dist, Taipei, 100225, Taiwan, Tel +886 2 2312-3456&num; 265317, Email [email protected]: Porcine-based dermal injectable collagen is effective for nasolabial fold correction. In the present study, a new dermal injectable collagen, incorporating a novel cross-linking technology and premixed with lidocaine, was introduced. The study aimed to determine the efficacy of the new dermal injectable collagen in improving bilateral nasolabial fold wrinkles, and reducing pain during injection.Patients and Methods: This prospective, double-blind, multicenter, parallel-group, randomized trial enrolled participants with moderate-to-severe bilateral nasolabial fold wrinkles from February 2019 to March 2021. Participants were randomly assigned to the test group (new dermal injectable collagen with lidocaine featuring a novel cross-linking technology) or control group (traditionally cross-linked dermal injectable collagen with lidocaine). Participants were monitored for adverse events (AEs), and for pain using the Thermometer Pain Scale (TPS) and a visual analog scale (VAS). Efficacy was measured using the Wrinkle Severity Rating Scale (WSRS) and the Global Aesthetic Improvement Scale (GAIS).Results: On the poor or better sides, the 2 groups exhibited a significant decrease in WSRS scores at 4, 12, 24, and 36 weeks after treatment, compared to baseline WSRS scores (all, p 0.05), indicating that pain reduction was similar in the 2 groups. All AEs were anticipated AEs associated with facial aesthetic injections, and most recovered within 0 to 30 days without sequelae. There were no differences in AEs between the 2 groups (all, p > 0.05).Conclusion: The new dermal injectable collagen with lidocaine exhibited better efficacy for correcting nasolabial fold wrinkles compared to the control group. Both relieved pain and produced only transient and tolerable AEs.Keywords: adverse event, bilateral nasolabial folds, dermal filler, pain, porcine collagen, wrinkle