Structures and mechanisms of the Arabidopsis auxin transporter PIN3.

The PIN-FORMED (PIN) protein family of auxin transporters mediates polar auxin transport and has crucial roles in plant growth and development1,2. Here we present cryo-electron microscopy structures of PIN3 from Arabidopsis thaliana in the apo state and in complex with its substrate indole-3-acetic acid and the inhibitor N-1-naphthylphthalamic acid (NPA). A. thaliana PIN3 exists as a homodimer, and its transmembrane helices 1, 2 and 7 in the scaffold domain are involved in dimerization. The dimeric PIN3 forms a large, joint extracellular-facing cavity at the dimer interface while each subunit adopts an inward-facing conformation. The structural and functional analyses, along with computational studies, reveal the structural basis for the recognition of indole-3-acetic acid and NPA and elucidate the molecular mechanism of NPA inhibition on PIN-mediated auxin transport. The PIN3 structures support an elevator-like model for the transport of auxin, whereby the transport domains undergo up-down rigid-body motions and the dimerized scaffold domains remain static.

Prevalence of depression and its association with quality of life in patients after pacemaker implantation during the COVID-19 pandemic: A network analysis.

Background: This study was designed to investigate the prevalence and predictors of depression in patients after pacemaker implantation during the COVID-19 pandemic in addition to identifying specific depressive symptoms associated with quality of life (QOL) using network analysis (NA). Methods: This cross-sectional, observational study was conducted in China between July 1, 2021, and May 17, 2022. Descriptive analysis was used to calculate depression prevalence. Univariate analyses were used to compare differences in demographic and clinical characteristics between depressed and non-depressed patients following pacemaker implantation. Binary logistic regression analysis was used to assess factors independently associated with depression. Network analysis "expected influence," and flow function indexes were used to identify symptoms central to the depression network of the sample and depressive symptoms that were directly associated with QOL, respectively. Network stability was examined using a case-dropping bootstrap procedure. Results: In total, 206 patients implanted with a pacemaker met the study entry criteria and completed the assessment. The overall prevalence of depression (PHQ-9 total score ≥ 5) was 39.92% [95% confidence interval (CI) = 29.37-42.47%]. A binary logistic regression analysis revealed that patients with depression were more likely to report a poor health status (p = 0.031), severe anxiety symptoms (p < 0.001), and fatigue (p < 0.001). In the network model for depression, "Sad mood," "Poor Energy," and "Guilt" were the most influential symptoms. "Fatigue" had the strongest negative association with QOL, followed by "Sad mood" and "Appetite". Conclusion: Depression is common among patients having undergone pacemaker implantation during the COVID-19 pandemic. Anxiety, central symptoms of depression (i.e., "Sad mood", "Poor Energy", and "Guilt") and depressive symptoms linked to QOL (i.e., "Sad mood", "Appetite", and "Fatigue") identified in this study are promising targets for interventions and preventive measures for depression in patients who have undergone pacemaker implants.

The relationship of intent to be COVID-19 vaccinated with depression, anxiety, insomnia, pain and smoking among Chinese patients with a pacemaker.

Background: This study examined the intent to be COVID-19 vaccinated and its correlates among patients with a pacemaker. Methods: This observational study was carried out between July 1, 2021, and May 17, 2022 in Beijing, China. Patients with a pacemaker were consecutively invited by a research physician to participate in the study. Intent to be COVID-19 vaccinated, depression, anxiety, insomnia, pain and smoking were measured with standard scales or questions. Results: Of the 206 participating patients, 72.82% (N = 150; 95% confidence interval [CI]: 66.74%-78.89%) expressed an intention to be COVID-19 vaccinated. Intent to be COVID-19 vaccinated was not significantly associated with severity of depression, anxiety, and insomnia. Multiple logistic regression analysis revealed that patients believing that COVID-19 vaccines provided protection and smokers were more likely to express an intention to receive COVID-19 vaccines. In contrast, older patients and those with higher level of physical pain were less likely to express an intention to be vaccinated against COVID-19. Conclusions: Specific vaccination promotion strategies should be implemented targeting this vulnerable segment of the population.

[Visual detection of H1 subtype and identification of N1, N2 subtype of avian influenza virus by reverse transcription loop-mediated isothermal amplification assay].

In order to visually detect H1, N1 and N2 subtype of avian influenza virus (AIV), three reverse transcription loop-mediated isothermal amplification (RT-LAMP) assays were developed. According to the sequences of AIV gene available in GenBank, three degenerate primer sets specific to HA gene of H1 subtype AIV, NA gene of N1 and N2 subtype AIV were designed, and the reaction conditions were optimized. The results showed that all the assays had no cross-reaction with other subtype AIV and other avian respiratory pathogens, and the detection limit was higher than that of conventional RT-PCR. These assays were performed in water bath within 50 minutes. Without opening tube, the amplification result could be directly determined by inspecting the color change of reaction system as long as these assays were fin-ished. Fourteen specimens of H1N1 subtype and eight specimens of H1N2 subtype of AIV were identified from the 120 clinical samples by RT-LAMP assays developed, which was consistent with that of virus isolation. These results suggested that the three newly developed RT-LAMEP assays were simple, specific and sensitive and had potential for visual detection of H1, N1 and N2 subtype of AIV in field.

Construction and application of a novel genetically engineered Aspergillus oryzae for expressing proteases

Background: We aimed to test the possibility of improving polypeptide production from soybean meal fermentation by engineered Aspergillus oryzae strains. Four different protease genes were cloned and transformed into wild-type A. oryzae, and the engineered A. oryzae strains were then used for soybean meal fermentation. Results: The results showed different degrees of improvement in the protease activity of the four transformants when compared with wild-type A. oryzae. A major improvement in the polypeptide yield was achieved when these strains were used in soybean meal fermentation. The polypeptide conversion rate of one of the four transformants, A. oryzae pep, reached 35.9%, which was approximately twofold higher than that exhibited by wild-type A. oryzae. Amino acid content analysis showed that the essential amino acid content and amino acid composition of the fermentation product significantly improved when engineered A. oryzae strains were used for soybean meal fermentation. Conclusions: These findings suggest that cloning of microbial protease genes with good physicochemical properties and expressing them in an ideal host such as A. oryzae is a novel strategy to enhance the value of soybean meal.