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Trans-acting small interfering RNAs (tasiRNAs) are 21-nt phased (phased siRNAs) resulting from successive DCL-catalyzed processing from the end of a double-stranded RNA substrate originating from the RDR of an AGO-catalyzed cleaved RNA at a micro RNA target site. Plant tasiRNAs have been synthesized to produce synthetic tasiRNAs (syn-tasiRNAs) targeting viral RNAs that confer viral resistance. In this study, we engineered syn-tasiRNAs to target potato virus Y (PVY) infection by replacing five native siRNAs of TAS1c with 210-bp fragments from the coat protein (CP) region of the PVY genome. The results showed that the transient expression of syn-tasiR-CPpvy2 in Nicotiana benthamiana (N. benthamiana) plants conferred antiviral resistance, supported by the absence of PVY infection symptoms and viral accumulation. This indicated that syn-tasiR-CPpvy2 successfully targeted and silenced the PVY CP gene, effectively inhibiting viral infection. syn-tasiR-CPpvy1 displayed attenuated symptoms and decreased viral accumulation in these plants However, severe symptoms of PVY infection and a similar amount of viral accumulation as the control were observed in plants expressing syn-tasiR-CPpvy3. syn-tasiR-CPpvy/pvx, which targets both PVY and potato virus X (PVX), was engineered using a single precursor. After the transient expression of syn-tasiR-CPpvy/pvx3 and syn-tasiR-CPpvy/pvx5 in N. benthamiana, the plants were resistant to both PVY and PVX. These results suggested that engineered syn-tasiRNAs could not only specifically induce antiviral resistance against one target virus but could also be designed for multi-targeted silencing of different viruses, thereby preventing complex virus infection in plants.

Methyltransferase (MTase) enzymes catalyze the addition of a methyl group to a variety of biological substrates. MTase-like (METTL) proteins are Class I MTases whose enzymatic activities contribute to the epigenetic and epitranscriptomic regulation of multiple cellular processes. N 6 -adenosine methylation (m 6 A) is a common chemical modification of eukaryotic and viral RNA whose abundance is jointly regulated by MTases and METTLs, demethylases, and m 6 A binding proteins. m 6 A affects various cellular processes including RNA degradation, post-transcriptional processing, and antiviral immunity. Here, we used Nicotiana benthamiana and plum pox virus (PPV), an RNA virus of the Potyviridae family, to investigated the roles of MTases in plant-virus interaction. RNA sequencing analysis identified MTase transcripts that are differentially expressed during PPV infection; among these, accumulation of a METTL gene was significantly downregulated. Two N. benthamiana METTL transcripts (NbMETTL1 and NbMETTL2) were cloned and further characterized. Sequence and structural analyses of the two encoded proteins identified a conserved S-adenosyl methionine (SAM) binding domain, showing they are SAM-dependent MTases phylogenetically related to human METTL16 and Arabidopsis thaliana FIONA1. Overexpression of NbMETTL1 and NbMETTL2 caused a decrease of PPV accumulation. In sum, our results indicate that METTL homologues participate in plant antiviral responses.

Potato ( Solanum tuberosum L. ) is an important vegetable crop that plays a pivotal role in the world, especially given its potential to feed the world population and to act as the major staple food in many developing countries. Every year, significant crop loss is caused by viral diseases due to a lack of effective agrochemical treatments, since only transmission by insect vectors can be combated with the use of insecticides, and this has been an important factor hindering potato production. With the rapid development of molecular biology and plant genetic engineering technology, transgenic approaches and non-transgenic techniques (RNA interference and CRISPR-cas9) have been effectively employed to improve potato protection against devastating viruses. Moreover, the availability of viral sequences, potato genome sequences, and host immune mechanisms has remarkably facilitated potato genetic engineering. In this study, we summarize the progress of antiviral strategies applied in potato through engineering either virus-derived or plant-derived genes. These recent molecular insights into engineering approaches provide the necessary framework to develop viral resistance in potato in order to provide durable and broad-spectrum protection against important viral diseases of solanaceous crops.

Purpose: Safety and efficiency of ambulatory pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) patients is worthy of attention, since patients always have severe systemic diseases. The purpose of this study was to compare the incidence of same-day cancellation of PPV for PDR between outpatients and inpatients and to analyze the causes of cancellations., Patients and Methods: This is a retrospective review of consecutive PPV procedures for PDR from January 2019 to April 2021 at either the ambulatory or the inpatient surgery center in an academic tertiary referral center. Data on patient surgery plan, same-day surgical cancellation and follow-up were recorded. Differences in cancellation rate and reasons for cancellation (e.g. medical factors, patient reasons and administrative problems) between outpatients and inpatients were compared., Results: In total, 1810 consecutive PPV procedures of 1367 patients were identified; 1509 (83.4%) were managed as inpatient surgeries and 301 (16.6%) as outpatient surgeries. The total same-day cancellation rate was 5.2% for all patients. Although outpatients were younger (51 years vs 52 years, P < 0.001), had less proportion of hypertension (60.5% vs 74.0%), coronary artery disease (10.0% vs 18.8%), renal insufficiency (9.3% vs 18.0%) and cerebrovascular diseases (1.0% vs 11.4%) (all P < 0.001), had less proportion of patients with ASA III status (14.9% vs 27.4%, P < 0.001), and had higher proportion of regional anesthesia with MAC (19.9% vs 5.0%, P < 0.001), the cancellation proportion was significantly higher for outpatients than inpatients (12.3% vs 3.8%, P < 0.001). Overall, the most common reason for surgical cancellation was medical factors, occurring more frequently in outpatients than inpatients (91.9% vs 68.4%, P = 0.012)., Conclusion: Same-day cancellation is higher in outpatient pars plana vitrectomy for proliferative diabetic retinopathy. To reduce ambulatory surgery cancellations, it is important to strengthen the monitoring of preoperative systemic comorbidities and adjust medication if necessary., Competing Interests: The authors report no conflicts of interest in this work., (© 2022 Xi et al.)

Proteins of the alkylation B (AlkB) superfamily show RNA demethylase activity removing methyl adducts from N 6 -methyladenosine (m 6 A). m 6 A is a reversible epigenetic mark of RNA that regulates human virus replication but has unclear roles in plant virus infection. We focused on Potyvirus-the largest genus of plant RNA viruses-and report here the identification of AlkB domains within P1 of endive necrotic mosaic virus (ENMV) and an additional virus of a putative novel species within Potyvirus. We show that Nicotiana benthamiana m 6 A levels are reduced by infection of plum pox virus (PPV) and potato virus Y (PVY). The two potyviruses lack AlkB and the results suggest a general involvement of RNA methylation in potyvirus infection and evolution. Methylated RNA immunoprecipitation sequencing of virus-infected samples showed that m 6 A peaks are enriched in plant transcript 3' untranslated regions and in discrete internal and 3' terminal regions of PPV and PVY genomes. Down-regulation of N. benthamiana AlkB homologues of the plant-specific ALKBH9 clade caused a significant decrease in PPV and PVY accumulation. In summary, our study provides evolutionary and experimental evidence that supports the m 6 A implication and the proviral roles of AlkB homologues in Potyvirus infection., (© 2022 The Authors. Molecular Plant Pathology published by British Society for Plant Pathology and John Wiley & Sons Ltd.)

Purpose: Mivacurium, the shortest-acting benzylisoquinoline nondepolarizing neuromuscular blocker used in clinical practice, is suitable for short-term ambulatory operations under general anesthesia. We investigated the neuromuscular blockade effect of different maintenance doses of mivacurium during ambulatory vitreoretinal surgery under general anesthesia and tried to determine the appropriate maintenance dose., Patients and Methods: Ninety-nine patients undergoing general anesthesia for elective ambulatory vitreoretinal surgery were randomly divided into three groups using the random number table method. Patients received three maintenance doses of mivacurium during surgery as follows: 3 μg/(kg·min) in group M1 (n = 33), 6 μg/(kg·min) in group M2 (n = 33), and 9 μg/(kg·min) in group M3 (n = 33). The primary outcome was the time from mivacurium withdrawal to a train-of-four stimulation ratio (TOFr) ≥ 0.9, and the secondary outcomes were the time from mivacurium withdrawal to TOFr ≥ 0.7, extubation time, incidence of TOFr < 0.9 after surgery and neuromuscular block effect., Results: The time from mivacurium withdrawal to TOFr ≥ 0.9 and to TOFr ≥ 0.7 was significantly longer in group M3 than in groups M1 and M2 (25.6±7.2 min vs 16.4±5.9 min and 18.6±5.3 min, P < 0.001; 22.1±6.3 min vs 13.6 ± 5.8 min and 15.5 ± 4.8 min; P < 0.001, respectively). There was a significant difference in the extubation time, the incidence of TOFr < 0.9 during extubation and upon leaving the operating room between group M3 and group M1 (all P < 0.05), but there was no such significant difference between group M2 and group M1 (all P > 0.05). The intraoperative depth of neuromuscular blockade in the three groups was significantly different, with 69.7% shallow block in group M1, 75.8% moderate block in group M2 and 63.6% deep block in group M3 ( P < 0.001). One patient in group M1 experienced slight body movement during the operation., Conclusion: An intraoperative continuous infusion of 6 μg/(kg·min) mivacurium can not only achieve good postoperative recovery but also provide a satisfactory neuromuscular blockade effect during surgery, and this maintenance dose is suitable for neuromuscular blockade during ambulatory vitreoretinal surgery., Competing Interests: The authors report no conflicts of interest in this work., (© 2022 Zhang et al.)

In recent years, m6A RNA methylation has attracted broad interest and is becoming a hot research topic. It has been demonstrated that there is a strong association between m6A and viral infection in the human system. The life cycles of plant RNA viruses are often coordinated with the mechanisms of their RNA modification. Here, we reviewed recent advances in m6A methylation in plant viruses. It appears that m6A methylation plays a dual role during viral infection in plants. On the one hand, m6A methylation acts as an antiviral immune response induced by virus infection, which inhibits viral replication or translation through the methylation of viral genome RNAs. On the other hand, plant viruses could disrupt the m6A methylation through interacting with the key proteins of the m6A pathway to avoid modification. Those plant viruses containing ALKB domain are discussed as well. Based on this mechanism, we propose that new strategies for plant virus control could be designed with competitive antagonists of m6A-associated proteins.

Solar blind ultraviolet (SBUV) self-powered photodetectors (PDs) have a great number of applications in civil and military exploration. Ga 2 O 3 is a prospective candidate for SBUV detection owing to its reasonable bandgap corresponding to the SBUV waveband. Nevertheless, the previously reported Ga 2 O 3 photovoltaic devices had low photoresponse performance and were still far from the demands of practical application. Herein, we propose an idea of using spiro-MeOTAD (spiro) as the SBUV transparent conductive layer to construct p-i-n PDs (p-spiro/Ga 2 O 3 /n-Si). With the aid of double built-in electric fields, the designed p-i-n PDs could operate without any external power source. Furtherly, the influence of spiro thickness on improving the photoelectric performance of devices is investigated in detail and the optimum device is achieved, translating to a peak responsivity of 192 mA/W upon a weak 254 nm light illumination of 2 μW/cm 2 at zero bias. In addition, the I - t curve of our PD shows binary response characteristics and a four-stage current response behavior under a small forward bias, and also, its underlying working mechanism is analyzed. In sum, this newly developed device presents great potential for booming the high energy-efficient optoelectronic devices in the short run.

Fusarium wilt of potato is one of the most common diseases of potato in China, and is becoming a serious threat in potato production. It has been reported that osthole from Cnidium monnieri ( L. ) Cusson can inhibit plant pathogens. Here, we test the anti-fungal activity of C. monnieri osthole against Fusarium oxysporum in potatoes. The results showed that at a concentration of 5 mg/mL, osthole was able to obviously inhibit mycelial growth of F. oxysporum . We found that osthole caused changes of mycelial morphology, notably hyphal swelling and darkening. Osthole significantly reduced the spore germination of Fusarium by 57.40%. In addition, osthole also inhibited the growth of other pathogens such as Fusarium moniliforme J. Sheld, Thanatephorus cucumeris Donk, and Alternaria alternata (Fr.) Keissl, but not Alternaria solani Jonesetgrout and Valsa mali Miyabe and G. Yamada. Our results suggest that osthole has considerable potential as an agent for the prevention and treatment of potato Fusarium wilt.

Background: Tumor necrosis factor alpha (TNF-alpha) could trigger p38 mitogen-activated protein kinase (MAPK) activation. Conversely phosphorylated p38 (p-p38) could induce the upregulation of TNF-alpha. In this study, we examined the hypothesis that chronic constrictive injury (CCI) of the sciatic nerve could promote spinal cord release of TNF-alpha and produce allodynia via the p38 MAPK pathway., Methods: Sprague-Dawley rats were divided into five groups: 1) naïve control rats, 2) sham surgery rats, 3) CCI surgery rats without treatment, 4) CCI surgery rats with saline (0.9%) treatment, and 5) CCI surgery rats with the p38 MAPK inhibitor SB203580 treatment. In treatment groups, saline or SB203580 (2 microg, twice a day) was given intrathecally starting 1 day before or 1 day or 7 days after CCI. All rats were killed at different times after surgery to examine p38 MAPK activity and TNF-alpha levels in the spinal cord by Western blot analysis or immunohistochemistry. Mechanical allodynia was tested by a series of von Frey hairs 3, 7, and 14 days after surgery., Results: p-p38 MAPK was significantly increased at 3, 7, and 14 days after CCI surgery compared with time-matched shams (P < 0.05). Peripheral nerve injury induced mechanical allodynia and enhanced spinal concentrations of TNF-alpha (P < 0.05). Pretreatment or early treatment with SB203580 inhibited p38 MAPK activity, resulting in reduction of TNF-alpha synthesis and attenuation of mechanical allodynia (P < 0.05)., Conclusion: p38 MAPK activation is one aspect of the signaling cascade that culminates in TNF-alpha synthesis and contributes to mechanical allodynia after peripheral nerve injury.