The ACR11 encodes a novel type of chloroplastic ACT domain repeat protein that is coordinately expressed with GLN2 in Arabidopsis

<p>Abstract</p> <p>Background</p> <p>The ACT domain, named after bacterial aspartate kinase, chorismate mutase and TyrA (prephenate dehydrogenase), is a regulatory domain that serves as an amino acid-binding site in feedback-regulated amino acid metabolic enzymes. We have previously identified a novel type of ACT domain-containing protein family, the ACT domain repeat (ACR) protein family, in <it>Arabidopsis</it>. Members of the ACR family, ACR1 to ACR8, contain four copies of the ACT domain that extend throughout the entire polypeptide. Here, we describe the identification of four novel ACT domain-containing proteins, namely ACR9 to ACR12, in <it>Arabidopsis</it>. The ACR9 and ACR10 proteins contain three copies of the ACT domain, whereas the ACR11 and ACR12 proteins have a putative transit peptide followed by two copies of the ACT domain. The functions of these plant ACR proteins are largely unknown.</p> <p>Results</p> <p>The ACR11 and ACR12 proteins are predicted to target to chloroplasts. We used protoplast transient expression assay to demonstrate that the <it>Arabidopsis </it>ACR11- and ACR12-green fluorescent fusion proteins are localized to the chloroplast. Analysis of an <it>ACR11 </it>promoter-β-glucuronidase (GUS) fusion in transgenic <it>Arabidopsis </it>revealed that the GUS activity was mainly detected in mature leaves and sepals. Interestingly, coexpression analysis revealed that the <it>GLN2</it>, which encodes a chloroplastic glutamine synthetase, has the highest mutual rank in the coexpressed gene network connected to <it>ACR11</it>. We used RNA gel blot analysis to confirm that the expression pattern of <it>ACR11 </it>is similar to that of <it>GLN2 </it>in various organs from 6-week-old <it>Arabidopsis</it>. Moreover, the expression of <it>ACR11 </it>and <it>GLN2 </it>is highly co-regulated by sucrose and light/dark treatments in 2-week-old <it>Arabidopsis </it>seedlings.</p> <p>Conclusions</p> <p>This study reports the identification of four novel ACT domain repeat proteins, ACR9 to ACR12, in <it>Arabidopsis</it>. The ACR11 and ACR12 proteins are localized to the chloroplast, and the expression of <it>ACR11 </it>and <it>GLN2 </it>is highly coordinated. These results suggest that the <it>ACR11 </it>and <it>GLN2 </it>genes may belong to the same functional module. The <it>Arabidopsis </it>ACR11 protein may function as a regulatory protein that is related to glutamine metabolism or signaling in the chloroplast.</p

Outcome for self-expandable metal stents in patients with malignant gastroduodenal obstruction: A single center experience

SummaryBackgroundMalignant gastric outlet obstruction causes significant malnutrition and morbidity. The implantation of a metallic stent is an alternative palliative treatment to allow the intake of food in these patients.Patients and MethodsThirty-eight consecutive patients with malignant gastric outlet obstruction who had received an uncovered metallic stent placement in our department from April 2010 to April 2012 were enrolled for analysis. The mean follow-up time was 6.3 months. Food intake, measured by the Gastric Outlet Obstruction Scoring System, complications, duration of stent patency, and survival were evaluated.ResultsThe technical and clinical success rates of the procedure were 100% and 94.7%, respectively. The Gastric Outlet Obstruction Scoring System scores were significantly improved at 1 day, 7 days, and 30 days after the implantation compared with those prior to the procedure (p < 0.001). Aspiration pneumonia developed in two patients (5.2%) after the procedure. One of these patients developed respiratory failure and died 3 days later. Stent dysfunction developed in 11 of 38 patients (28.9%) during the follow-up period; one patient (2.6%) experienced migration of the stent 38 days later due to resolution of the stricture; 10 patients (26.3%) had stent restenosis. The median time of stent patency was 120 days. The presence of peritoneal carcinomatosis when the procedure was carried out was a significantly poor predictive factor of stent patency [hazard ratio (HR) 7.9, p = 0.039]. The median survival of the patients was 156 days. Poor performance status ≥3; HR 2.647, p = 0.012) and nongastric cancer origin (HR 3.466, p = 0.008) were associated with a significantly short survival time.ConclusionMetallic stent placement is an effective and relatively safe treatment for patients with malignant gastric outlet obstruction

An Aluminum Microfluidic Chip Fabrication Using a Convenient Micromilling Process for Fluorescent Poly(dl-lactide-co-glycolide) Microparticle Generation

This study presents the development of a robust aluminum-based microfluidic chip fabricated by conventional mechanical micromachining (computer numerical control-based micro-milling process). It applied the aluminum-based microfluidic chip to form poly(lactic-co-glycolic acid) (PLGA) microparticles encapsulating CdSe/ZnS quantum dots (QDs). A cross-flow design and flow-focusing system were employed to control the oil-in-water (o/w) emulsification to ensure the generation of uniformly-sized droplets. The size of the droplets could be tuned by adjusting the flow rates of the water and oil phases. The proposed microfluidic platform is easy to fabricate, set up, organize as well as program, and is valuable for further applications under harsh reaction conditions (high temperature and/or strong organic solvent systems). The proposed method has the advantages of actively controlling the droplet diameter, with a narrow size distribution, good sphericity, as well as being a simple process with a high throughput. In addition to the fluorescent PLGA microparticles in this study, this approach can also be applied to many applications in the pharmaceutical and biomedical area

Detection of coronary lesions in Kawasaki disease by Scaled-YOLOv4 with HarDNet backbone

IntroductionKawasaki disease (KD) may increase the risk of myocardial infarction or sudden death. In children, delayed KD diagnosis and treatment can increase coronary lesions (CLs) incidence by 25% and mortality by approximately 1%. This study focuses on the use of deep learning algorithm-based KD detection from cardiac ultrasound images.MethodsSpecifically, object detection for the identification of coronary artery dilatation and brightness of left and right coronary artery is proposed and different AI algorithms were compared. In infants and young children, a dilated coronary artery is only 1-2 mm in diameter than a normal one, and its ultrasound images demonstrate a large amount of noise background-this can be a considerable challenge for image recognition. This study proposes a framework, named Scaled-YOLOv4-HarDNet, integrating the recent Scaled-YOLOv4 but with the CSPDarkNet backbone replaced by the CSPHarDNet framework.ResultsThe experimental result demonstrated that the mean average precision (mAP) of Scaled-YOLOv4-HarDNet was 72.63%, higher than that of Scaled YOLOv4 and YOLOv5 (70.05% and 69.79% respectively). In addition, it could detect small objects significantly better than Scaled-YOLOv4 and YOLOv5.ConclusionsScaled-YOLOv4-HarDNet may aid physicians in detecting KD and determining the treatment approach. Because relatively few artificial intelligence solutions about images for KD detection have been reported thus far, this paper is expected to make a substantial academic and clinical contribution

MRE11 promotes oral cancer progression through RUNX2/CXCR4/AKT/FOXA2 signaling in a nuclease-independent manner

MRE11, the nuclease component of RAD50/MRE11/NBS1 DNA repair complex which is essential for repair of DNA double-strand-breaks in normal cells, has recently garnered attention as a critical factor in solid tumor development. Herein we report the crucial role of MRE11 in oral cancer progression in a nuclease-independent manner and delineate its key downstream effectors including CXCR4. MRE11 expression in oral cancer samples was positively associated with tumor size, cancer stage and lymph node metastasis, and was predictive of poorer patient survival and radiotherapy resistance. MRE11 promoted cell proliferation/migration/invasion in a nuclease-independent manner but enhanced radioresistance via a nuclease-dependent pathway. The nuclease independent promotion of EMT and metastasis was mediated by RUNX2, CXCR4, AKT, and FOXA2, while CXCR4 neutralizing antibody mitigated these effects in vitro and in vivo. Collectively, MRE11 may serve as a crucial prognostic factor and therapeutic target in oral cancer, displaying dual nuclease dependent and independent roles that permit separate targeting of tumor vulnerabilities in oral cancer treatment

Comparison of Human and Soil Candida tropicalis Isolates with Reduced Susceptibility to Fluconazole

Infections caused by treatment-resistant non-albicans Candida species, such as C. tropicalis, has increased, which is an emerging challenge in the management of fungal infections. Genetically related diploid sequence type (DST) strains of C. tropicalis exhibiting reduced susceptibility to fluconazole circulated widely in Taiwan. To identify the potential source of these wildly distributed DST strains, we investigated the possibility of the presence in soil of such C. tropicalis strains by pulsed field gel electrophoresis (PFGE) and DST typing methods. A total of 56 C. tropicalis isolates were recovered from 26 out of 477 soil samples. Among the 18 isolates with reduced susceptibility to fluconazole, 9 belonged to DST149 and 3 belonged to DST140. Both DSTs have been recovered from our previous studies on clinical isolates from the Taiwan Surveillance of Antimicrobial Resistance of Yeasts (TSARY) program. Furthermore, these isolates were more resistant to agricultural azoles. We have found genetically related C. tropicalis exhibiting reduced susceptibility to fluconazole from the human hosts and environmental samples. Therefore, to prevent patients from acquiring C. tropicalis with reduced susceptibility to azoles, prudent use of azoles in both clinical and agricultural settings is advocated

Effects of Hepatocyte CD14 Upregulation during Cholestasis on Endotoxin Sensitivity

Cholestasis is frequently related to endotoxemia and inflammatory response. Our previous investigation revealed a significant increase in plasma endotoxin and CD14 levels during biliary atresia. We therefore propose that lipopolysacharides (LPS) may stimulate CD14 production in liver cells and promote the removal of endotoxins. The aims of this study are to test the hypothesis that CD14 is upregulated by LPS and investigate the pathophysiological role of CD14 production during cholestasis. Using Western blotting, qRT-PCR, and promoter activity assay, we demonstrated that LPS was associated with a significant increase in CD14 and MD2 protein and mRNA expression and CD14 promoter activity in C9 rat hepatocytes but not in the HSC-T6 hepatic stellate cell line in vitro. To correlate CD14 expression and endotoxin sensitivity, in vivo biliary LPS administration was performed on rats two weeks after they were subjected to bile duct ligation (BDL) or a sham operation. CD14 expression and endotoxin levels were found to significantly increase after LPS administration in BDL rats. These returned to basal levels after 24 h. In contrast, although endotoxin levels were increased in sham-operated rats given LPS, no increase in CD14 expression was observed. However, mortality within 24 h was more frequent in the BDL animals than in the sham-operated group. In conclusion, cholestasis and LPS stimulation were here found to upregulate hepatic CD14 expression, which may have led to increased endotoxin sensitivity and host proinflammatory reactions, causing organ failure and death in BDL rats

Amyloid-Beta (Aβ) D7H Mutation Increases Oligomeric Aβ42 and Alters Properties of Aβ-Zinc/Copper Assemblies

Amyloid precursor protein (APP) mutations associated with familial Alzheimer's disease (AD) usually lead to increases in amyloid β-protein (Aβ) levels or aggregation. Here, we identified a novel APP mutation, located within the Aβ sequence (AβD7H), in a Taiwanese family with early onset AD and explored the pathogenicity of this mutation. Cellular and biochemical analysis reveal that this mutation increased Aβ production, Aβ42/40 ratio and prolonged Aβ42 oligomer state with higher neurotoxicity. Because the D7H mutant Aβ has an additional metal ion-coordinating residue, histidine, we speculate that this mutation may promote susceptibility of Aβ to ion. When co-incubated with Zn2+ or Cu2+, AβD7H aggregated into low molecular weight oligomers. Together, the D7H mutation could contribute to AD pathology through a “double punch” effect on elevating both Aβ production and oligomerization. Although the pathogenic nature of this mutation needs further confirmation, our findings suggest that the Aβ N-terminal region potentially modulates APP processing and Aβ aggregation, and further provides a genetic indication of the importance of Zn2+ and Cu2+ in the etiology of AD