Molecular epidemiology analysis of fowl adenovirus detected from apparently healthy birds in eastern China.

BACKGROUND: Fowl adenovirus is of major concern to the poultry industry worldwidely. In order to monitor the prevalent status of Fowl adenovirus in China, a total of 1920 clinical samples from apparently healthy birds in the 25 sites of poultry flocks, Slaughterhouse and living bird markets from 8 provinces in eastern China were collected and detected by PCR, sequencing, and phylogenetic analysis. RESULTS: The epidemiological survey showed that Fowl adenoviruses were detected in living bird markets, and circulating in a variety of fowl species, including chickens, ducks, goose and pigeons. Among the 1920 clinical samples, 166 samples (8.65%) were positive in the fowl adenovirus PCR detection. In this study, totally all the 12 serotypes (serotypes of 1, 2, 3, 4, 5, 6, 7, 8A, 8B, 9, 10 and 11) fowl adenoviruses were detected, the most prevalent serotype was serotype 1. Phylogenetic analysis indicated that 166 FAdVs of 12 serotypes were divided into 5 fowl adenovirus species (Fowl aviadenovirus A, B, C, D, E). CONCLUSIONS: In the epidemiological survey, 8.65% of the clinical samples from apparently healthy birds were positive in the fowl adenovirus PCR detection. Totally all the 12 serotypes fowl adenoviruses were detected in a variety of fowl species, which provided abundant resources for the research of fowl adenoviruses in China. The newly prevalent FAdV serotypes provides valuable information for the development of an effective control strategy for FAdV infections in fowls.

Research on Medical Security System Based on Zero Trust.

With the rapid development of Internet of Things technology, cloud computing, and big data, the combination of medical systems and information technology has become increasingly close. However, the emergence of intelligent medical systems has brought a series of network security threats and hidden dangers, including data leakage and remote attacks, which can directly threaten patients' lives. To ensure the security of medical information systems and expand the application of zero trust in the medical field, we combined the medical system with the zero-trust security system to propose a zero-trust medical security system. In addition, in its dynamic access control module, based on the RBAC model and the calculation of user behavior risk value and trust, an access control model based on subject behavior evaluation under zero-trust conditions (ABEAC) was designed to improve the security of medical equipment and data. Finally, the feasibility of the system is verified through a simulation experiment.

An Infusion Containers Detection Method Based on YOLOv4 with Enhanced Image Feature Fusion.

The detection of infusion containers is highly conducive to reducing the workload of medical staff. However, when applied in complex environments, the current detection solutions cannot satisfy the high demands for clinical requirements. In this paper, we address this problem by proposing a novel method for the detection of infusion containers that is based on the conventional method, You Only Look Once version 4 (YOLOv4). First, the coordinate attention module is added after the backbone to improve the perception of direction and location information by the network. Then, we build the cross stage partial-spatial pyramid pooling (CSP-SPP) module to replace the spatial pyramid pooling (SPP) module, which allows the input information features to be reused. In addition, the adaptively spatial feature fusion (ASFF) module is added after the original feature fusion module, path aggregation network (PANet), to facilitate the fusion of feature maps at different scales for more complete feature information. Finally, EIoU is used as a loss function to solve the anchor frame aspect ratio problem, and this improvement allows for more stable and accurate information of the anchor aspect when calculating losses. The experimental results demonstrate the advantages of our method in terms of recall, timeliness, and mean average precision (mAP).

First Report of Target Spot Caused by Rhizoctonia solani AG-6 in Tobacco in China.

Tobacco is an annual and solanaceous crop, which is widely produced in China. In July 2020, tobacco target spot was observed on 50% of tobacco plants in a 5-ha commercial field of Bijie (27.32° N, 105.29° E), Guizhou province, China. Typical symptoms firstly appeared on the old leaves as round watery spots. Then the spots became a diameter of 2 to 20 cm, with concentric ring lines and dead spots. Fifteen small pieces (5 × 5 mm) of leaf tissue were cut from the edge of the lesions, surface sterilized and placed on potato dextrose agar (PDA) medium amended with kanamycin (0.1 mg/ml). Isolate J136, one of five isolates with similar morphology, was selected for pathogen identification. The culture of the isolate on PDA was brown and exhibited radial mycelial growth after incubation at 28 oC in darkness for 5 days. Hyphae of the fungus were white at the beginning, turned light brown to brown at the later stages, and finally became thick and separated. Sclerotia were brown and produced on PDA after 25 days of incubation in the dark. These characteristics were similar to the colony characteristics of R. solani. The genomic DNA of Isolate J136 was extracted using the CTAB method. PCR analyses were conducted using the following primers specifically designed for the detection of individual AGs or subgroups of R. solani: AG-1 IA, IB and IC (Kuninaga 2003), AG-2-1, AG-2-2, IIIB, IV and LP (Carling et al. 2002), AG-3 PT (Misawa 2015), AG-4 HG-I and HG-II (Kuninaga 2003), and AGs-5-6 (Arakawa and Inagaki 2014). Among the 12 specific primer pairs, only AG-6-specific primers amplified a fragment of ca. 230 bp product, indicating that the tested strain belonged to R. solani AG-6. The sequence was deposited in GenBank with accession no. MZ379468. Using BLASTN search, the sequence of the gene was aligned with the voucher specimen, R. solani AG-6. A phylogenetic tree was constructed based on these sequences. After wards, Isolate J136 was tested for hyphal anastomosis reaction using the R. solani AG-6 standard strain according to the method described by Ogoshi (1987). The hyphal diameter at the point of anastomosis was reduced, with obvious anastomosis point, and the death of adjacent cells, indicating their anastomosis reactions (Anderson 1982). Thus, based on the morphological and genetic analyses, the fungus was identified as R. solani AG-6. To verify its pathogenicity, six plants (cv. Yunyan87) at the 5-to-6 leaf stage were inoculated with mycelial PDA plugs (5 mm in diameter). Leaves inoculated with PDA-only plugs served as the controls. Treated tobacco plants were maintained at a temperature range of 15 to 25 oC in a greenhouse with 85% relative humidity. After 5 days inoculation, typical symptoms were observed on the inoculated leaves, whereas no symptoms were observed on the control leaves. Koch's postulates were fulfilled by re-isolation of the pathogen from the diseased leaves. R. solani AG-2-2 is the only previously reported group of R. solani, which causes tobacco target spot in the field (Gonzalez et al. 2011). Therefore, to our knowledge, this is the first report of R. solani AG-6 causing target spot of tobacco in the field in China. Since considerable losses caused by the disease have frequently happened in this region, addition of this new group pathogen in the disease pool can be more problematic. Proper disease control strategies are in need to be developed to prevent further losses.

SLC19A1 May Serve as a Potential Biomarker for Diagnosis and Prognosis in Osteosarcoma.

BACKGROUND: Osteosarcoma is the most frequent primary malignant tumor of bone. SLC19A1 has been explored as a novel biomarker in some cancers. In this research, the diagnostic and prognostic value of SLC19A1 expression in osteosarcoma was evaluated by bioinformatics analysis. Data were sourced from the Gene Expression Omnibus (GEO) database. METHODS: Gene expression data and clinical materials of patients with osteosarcoma were collected from GSE42352 and GSE21257 datasets. The mRNA expression of SLC19A1 was compared between osteosarcoma cells and mesenchyme stem cells with the Wilcoxon rank-sum test. Moreover, receiver operating characteristic (ROC) curve analysis was performed to determine the diagnostic merit of SLC19A1 for osteosarcoma. The relationship between SLC19A1 and clinicopathological characteristics was analyzed using logistic regression. Besides, the correlation between SLC19A1 and survival rate was assessed using Kaplan-Meier and Cox regression. The biological functions of SLC19A1 were annotated and evaluated through gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA). RESULTS: SLC19A1 was significantly highly expressed in osteosarcoma cells (p < 0.001). The ROC curve showed an area under the curve of 0.899, which indicated a high diagnostic value. High SLC19A1 expression showed a negative correlation with Huvos grade [odds ratio (OR) = 0.09 for III vs. I, p = 0.014]. Kaplan-Meier survival analysis showed that the overall survival (OS) of the patients with high SLC19A1 expression was significantly poorer than the low SLC19A1 expression group (p = 0.016). The univariate analysis revealed that high SLC19A1 expression was associated with poor OS [p = 0.013, hazard ratio (HR) = 6.74, 95% CI = 1.49 - 30.46]. The multivariate analysis revealed that SLC19A1 expression (p = 0.014, HR = 8.03, 95% CI = 1.52 - 42.51) was independently correlated with OS. GSEA showed that genes in high expression group of SLC19A1 were enriched in KEGG pathways, including "Glyoxylate and dicarboxylate metabolism", "Oxidative phosphorylation", "Aminoacyl tRNA biosynthesis", "Base excision repair", "Pyrimidine metabolism" and "Proteasome". GSVA further suggested their importance in the progression of osteosarcoma. CONCLUSIONS: SLC19A1 may be a potential biomarker for diagnosis and prognosis in osteosarcoma.

[Effect of Denticleless E3 Ubiquitin Protein Ligase on Proliferation and Colone Formation of Multiple Myeloma Cells].

Objective To determine the effect of denticleless E3 ubiquitin protein ligase(DTL)on the proliferation and clone formation of multiple myeloma(MM)cells and investigate the related mechanism. Methods Mononuclear cells were extracted from 34 MM patients.Mononuclear cells harvested from 14 healthy volunteers were used as controls.Quantitative polymerase chain reaction was used to detect the change of DTL at mRNA level.Furthermore,12 MM patients and 2 controls were selected,in whom the change of DTL at protein level was detected by Western blot.Human MM cell line RPMI8226 was divided into control(CON)group and DTL-short hairpin RNA(DTL-shRNA)group,which was infected with the CON and DTL-shRNA virus,respectively,for 48 hours.The infection efficiency was detected by using flow cytometry,the knock-down efficiencies at mRNA and protein levels were detected by quantitative polymerase chain reaction and Western blot,the change of cell counts in the next 0,24,48,72,96 hours were measured with CCK8 assay.The CON and DTL-shRNA cells were cultured in semisolid medium.Ten days later,inverted phase microscopy was used to measure the number of colones that contain more than 50 cells,annexin V/propidium iodide double staining to detect apoptosis,and propidium iodide staning to detect cell cycle.Finally,Western blot was empoyed to detect the phosphorylation of P65 and inhibitory subunit-κBα(IκBα)in nuclear factor-κB(NF-κB)pathway and electrophoretic mobility shift assay(EMSA)to detect the NF-κB transcriptional ability. Results The DTL expression was(1.00±0.12)and(9.36±3.71),respectively in the bone marrow mononuclear cells of healthy volunteers and in the CD138+cells of MM patients(t=3.65,P=0.0024).DTL was also highly expressed in MM CD138+positive cells at protein level.After RPMI8226 was infected by CON and DTL-shRNA virus for 48 hours,green fluorescent protein-positive cells accounted for more than 90%.The relative expression of DTL was(1.00±0.01)and(0.21±0.04)(t=33.19,P<0.0001)at mRNA level and(0.52±0.13)and(0.11±0.02)at protein level(t=5.399,P=0.0057).CCK8 revealed that CON and DTL-shRNA cells proliferated by(1.00±0.03)vs.(1.00±0.02),(2.19±0.28)vs.(1.47±0.13),(3.50±0.14)vs.(2.24±0.19),(5.43±0.41)vs.(3.08±0.14),(7.42±0.17)vs.(4.29±013)after 0,24,48,72,and 96 hours(F=24.58,P=0.001).The number of colone containing more than 50 cells was in 76±4 in CON group and 0 in DTL-shRNA group(P<0.01).The proportion of G1 stage cells was(28.61±8.64)% in CON group and(57.25±10.37)% in DTL-shRNA group(t=3.675,P=0.0213).The proportion of annexin V+in CON and DTL-shRNA groups was(3.21±0.89)% vs.(34.71±18.68)%(t=2.895,P=0.0443).After RPMI8226 was infected with CON or DTL-shRNA virus for 48 hours,the relative expression of phosphorylation P65 was(1.52±0.14)vs.(0.82±0.11)(t=6.81,P=0.0024),the P65 relative expression was(0.25±0.04)vs.(0.24±0.08)(t=0.19,P=0.85),the CON and DTL-shRNA phosphorylation-IκBα relative expression was(0.19±0.03)vs.(0.13±0.02)(t=2.882,P=0.0449),and the IκBα was(0.22±0.05)vs.(1.01±0.06)(t=17.52,P<0.0001).Detection of the transcriptional ability of DTL-shRNA NF-κB by EMSA further confirmed the down-regulation of DTL suppressed the NF-κB transcriptional ability. Conclusions DTL is highly expressed in MM cells,and down-regulation of DTL suppresses the cell proliferation,inhibit the colony formation,and induce cell apoptosis and cell cycle arrest.The effect of DTL on the biological functions of MM cells is related to the change of NF-κB pathway.

[Ribosomal Protein S9 Expression in Multiple Myeloma and Its Effect on Cell Biological Function].

Objective To identify the expression of ribosomal protein S9(RPS9)in multiple myeloma(MM)and explore its effect on the biological characteristics of myeloma cells and the corresponding mechanisms. Methods Bone marrow mononuclear cells were harvested in 10 healthy volunteers(CON group)and bone marrow CD138 +cells from 30 MM patients(CD138+group).Quantitative polymerase chain reaction(qPCR)was performed to detect RPS9 expression at mRNA level.In three cases from CON group and 11 cases from CD138+group,Western blot was performed to detect RPS9 at protein level.GSE19784 dataset was employed to detect the relationships of RPS9 expression with the overall survival rate,nuclear factor-κB(NF-κB),small ubiquitin-like modifier(SUMO),and ubiquitin pathway.After the RPS9 knock-down vector was constructed,flow cytometry was performed to detect the infection efficiency and qPCR and Western blot to detect the knock-down efficiency.RPMI8226 was divided into CON group and RPS9-short hairpin RNA(shRNA)group,in which annexin V allophycocyanin/propidium iodide(PI)double staining was performed to detect the change of apoptosis,CCK8 to detect the proliferation change,and PI staining to detect cell cycle change.After sentrin-specific protease 1(SENP1)overexpression vector was constructed,Western blot was performed to detect the phosphorylation of P65 and inhibitory subunit-κBα(IκBα)from NF-κB pathway in CON,RPS9-shRNA,and RPS9-shRNA-SENP1 cells;in addition,annexin V/PI double staining was also performed to detect the apoptosis in these three cells. Results The relative expression of RPS9 in CON group and CD138+group was(1.00±0.12)and(5.45±0.71),respectively(t=4.291,P=0.0036).Western blot showed RPS9 expression was high in most myeloma CD138+cells.The high expression of RPS9 was associated with both extramedullary invasion and overall survival in GSE19784 dataset.After RPMI8226 was infected with CON or RPS9-shRNA lentivirus for 48 hours,flow cytometry confirmed that the infection efficiencies were above 90% in both groups.qPCR and Western blot confirmed that RPS9 expression was inhibited at both mRNA and protein levels.After RPMI8226 CON and RPS9-shRNA infected with virus for 48 hours,the proportion of annexin V-positive cells in CON and RPS9-shRNA cells was(3.47±0.37)% and(18.60±64.00)%(t=9.015,P=0.0008).The proliferation index significantly differed between CON group and RPS9-shRNA group at 72 hours(t=6.846,P=0.0024).When CON and RPS9-shRNA were infected with virus for 48 hours,the proportion of G2 phase cells was(29.28±3.42)% and(10.43±1.43)%,respectively(t=9.329,P=0.0007).The RPS9 expression was positively correlated with SENP1 in GSE19784 dataset and negatively correlated with IκBα coding gene NFKBIA.Western blot further confirmed that RPS9 knockdown inhibited the expression of SENP1,inhibited the phosphorylation of NF-κB subunit P65 and inhibitor IκBα,and promoted the expression of IκBα.Overexpression of SENP1 not only impeded this effect but also reduced RPS9-induced apoptosis. Conclusions RPS9 is highly expressed in MM CD138+cells and is associated with overall survival and extramedullary infiltration.Inhibition of RPS9 can promote apoptosis,cell cycle arrest,and proliferation of myeloma cells.RPS9 can affect the activation of NF-κB pathway and cell apoptosis through SENP1,suggesting that SENP1 may be a key factor in the biological effect of RPS9.

Acute downregulation of miR-199a attenuates sepsis-induced acute lung injury by targeting SIRT1.

MicroRNA-199a (miR-199a) is a novel gene regulator with an important role in inflammation and lung injury. However, its role in the pathogenesis of sepsis-induced acute respiratory distress syndrome (ARDS) is currently unknown. Our study explored the role of miR-199a in sepsis-induced ARDS and its mechanism of action. First, we found that LPS could upregulate miR-199a in alveolar macrophages. Downregulation of miR-199a inhibited the upregulation of inflammatory cytokines in alveolar macrophages and induced the remission of histopathologic changes, the reduction of proinflammatory cytokines, and the upregulation of apoptosis protein expression in an ARDS lung, showing a protective role for miR-199a. We further identified sirtuin 1 (SIRT1) as a direct target of miR-199a in alveolar macrophages, and the expression of SIRT1 was negatively correlated with the level of miR-199a. The protective role of miR-199a downregulation in LPS-stimulated alveolar macrophages and sepsis-induced ARDS could be attenuated by SIRT1 inhibitor. Taken together, these results indicate that downregulation of miR-199a might protect lung tissue against sepsis-induced ARDS by upregulation of SIRT1 through the suppression of excessive inflammatory responses and the inhibition of cellular apoptosis in lung tissue, suggesting its potential therapeutic effects on sepsis-induced ARDS.

MicroRNA-138 Aggravates Inflammatory Responses of Macrophages by Targeting SIRT1 and Regulating the NF-κB and AKT Pathways.

BACKGROUND/AIMS: With increased understanding of sepsis, mortality is decreasing. However, there is still a lack of effective therapeutic strategy. The inflammatory response of macrophages is critical during sepsis. METHODS: Macrophages were stimulated with LPS. Western blotting and qRT-PCR were used to detect inflammatory responses. Then, the inhibitor of microRNA-138 was transfected and Western blotting, qRT-PCR, H&E staining and ELISA were used to verify the role of microRNA-138 in inflammation. Then target gene prediction databases were used to predict the potential target of microRNA-138. Both animal and cell models under LPS challenges were established to verify the regulation of SIRT1 and microRNA-138 during inflammation. RESULTS: The present study showed that microRNA-138 was increased in macrophages stimulated with LPS. Additionally, the NF-κB and AKT pathways were both activated. The pre-treatment of microRNA-138 inhibitor decreased inflammatory factors, downregulated the NF-κB pathway, activated the AKT pathway and protected against organ damage in mice challenged with LPS. SIRT1 was demonstrated as a potential target of microRNA-138In macrophages stimulated with LPS, the inhibition effect of microRNA-138 inhibitor on inflammation was lost by SIRT1 siRNA pre-treatment. In the animal model, the protective effect of microRNA-138 antagomir disappeared in SIRT1 knockout mice. CONCLUSION: We demonstrated that miR-138 participated in the inflammatory process by inhibiting SIRT1 and activating the NF-κB pathway.

A Randomized, Placebo-Controlled, Double-Blind, Prospective Clinical Trial of Botulinum Toxin Type A in Prevention of Hypertrophic Scar Development in Median Sternotomy Wound.

BACKGROUND: Linear hypertrophic scar is a common surgical problem that can be difficult to manage, especially for the median sternotomy scar. Botulinum toxin type A (BTA) is widely used in cosmetic surgery and has been shown to improve scar quality recently. The aim of this study was to evaluate the efficacy of BTA injected in the early postoperative of median sternotomy on preventing scar formation. METHODS: In this prospective randomized controlled trial, 19 consecutive patients who underwent median sternotomy were enrolled. The median sternotomy wound in each patient was divided into the upper half and the lower half. Both halves of the wound were randomized to receive the treatment with either BTA or normal saline. At 6-month follow-up, scars were assessed using the Vancouver Scar Scale, scar widths were measured, and patients were asked to evaluate their overall satisfaction. RESULTS: Seventeen patients with median sternotomy wounds completed the entire study. At 6-month follow-up, the mean Vancouver Scar Scale score for the BTA-treated group was 3.44 ± 1.68 and for the normal saline control group was 6.29 ± 2.39, and there was a statistically significant difference between the two groups (P < 0.05). There were also significant improvements in scar width and patient satisfaction for the BTA-treated halves of the wounds (P < 0.05). CONCLUSIONS: The study demonstrates that early postoperative BTA injection can decrease scar formation and reduce scar width in median sternotomy wounds, and the overall appearance is more satisfactory. LEVEL OF EVIDENCE I: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Epigenetic Suppression of GADs Expression is Involved in Temporal Lobe Epilepsy and Pilocarpine-Induced Mice Epilepsy.

Recent studies have shown that histone acetylation is involved with the regulation of enzyme glutamate decarboxylases (GADs), including GAD67 and GAD65. Here, we investigated the histone acetylation modifications of GADs in the pathogenesis of epilepsy and explored the therapeutic effect of a novel second-generation histone deacetylase inhibitor (HDACi) JNJ-26481585 in epilepsy animals. We revealed the suppression of GADs protein and mRNA level, and histone hypoacetylation in patients with temporal lobe epilepsy and pilocarpine-induced epilepsy mice model. Double-immunofluorescence also indicated that the hypoacetyl-H3 was located in hippocampal GAD67/GAD65 positive neurons in epilepsy mice. JNJ-26481585 significantly reversed the decrease of the GAD67/GAD65 both protein and mRNA levels, and the histone hypoacetylation of GABAergic neurons in epilepsy mice. Meanwhile, single-cell real-time PCR performed in GFP-GAD67/GAD65 transgenic mice demonstrated that JNJ-26481585 induced increase of GAD67/GAD65 mRNA level in GABAergic neurons. Furthermore, JNJ-26481585 significantly alleviated the epileptic seizures in mice model. Together, our findings demonstrate inhibition of GADs gene via histone acetylation plays an important role in the pathgenesis of epilepsy, and suggest JNJ-26481585 as a promising therapeutic strategy for epilepsy.

Stereoselective α-indolylation of enals via an organocatalytic formal cross-coupling with indoles.

We report a novel organocatalytic one-pot cascade bromination-Michael-type Friedel-Crafts alkylation dearomatization-nucleophilic rearrangement aromatization cascade process for the direct α-indolylation of unfunctionalized enals from readily available indoles with good yields and high E selectivity. The simplicity and practicality of its high efficiency for formation of a new C(sp(2))-C(sp(2)) bond constitute the most attractive advantage of this reaction.

Protective effect of quercetin against oxidative stress and brain edema in an experimental rat model of subarachnoid hemorrhage.

Quercetin has been demonstrated to play an important role in altering the progression of ischemic brain injuries and neurodegenerative diseases by protecting against oxidative stress. The effects of quercetin on brain damage after subarachnoid hemorrhage (SAH), however, have not been investigated. This study was designed to explore the effects of quercetin on oxidative stress and brain edema after experimental SAH using four equal groups (n = 16) of adult male Sprague-Dawley (SD) rats, including a sham group, an SAH + vehicle group, an SAH + quercetin10 group, and an SAH + quercetin50 group. The rat SAH model was induced by injection of 0.3 ml of non-heparinised arterial blood into the prechiasmatic cistern. In the SAH + quercetin10 and SAH + quercetin50 groups, doses of 10 mg/kg and 50 mg/kg quercetin, respectively, were directly administered by intraperitoneal injection at 30 min, 12 h, and 24 h after SAH induction. Cerebral tissue samples were extracted for enzymatic antioxidant determination, lipid peroxidation assay, caspase-3 activity and water content testing 48 h after SAH. Treatment with a high dose (50 mg/kg) of quercetin markedly enhanced the activities of copper/zinc superoxide dismutase (CuZn-SOD) and glutathione peroxidase (GSH-Px), and treatment with this dose significantly reduced the level of malondialdehyde (MDA). Caspase-3 and brain edema was ameliorated and neurobehavioral deficits improved in rats that received the high dose of quercetin. The findings suggest that the early administration of optimal dose of quercetin may ameliorate brain damage and provide neuroprotection in the SAH model, potentially by enhancing the activity of endogenous antioxidant enzymes and inhibiting free radical generation.

Photoredox-Catalyzed Synthesis of C-Benzoselenazolyl/Benzothiazolyl Glycosides from 2-Isocyanoaryl Selenoethers/Thioethers and Glycosyl Bromides.

Molecules containing heteroatoms, such as Se and S, play an indispensable role in the discovery and design of pharmaceuticals, whereas Se has been less studied. Here, we described a photoredox strategy to synthesize C-benzoselenazolyl (Bs) glycosides from 2-isocyanoaryl selenoethers and glycosyl bromides. This reaction was carried out under mild conditions with high efficiency. C-Benzothiazolyl (Bt) glycosides could also be synthesized from 2-isocyanoaryl thioethers using this strategy. This method can access novel seleno/thiosugars, which will benefit Se/S-containing drug discovery.

Improving the mapping accuracy of soil heavy metals through an adaptive multi-fidelity interpolation method.

Soil heavy metal pollution poses a serious threat to environmental safety and human health. Accurately mapping the soil heavy metal distribution is a prerequisite for soil remediation and restoration at contaminated sites. To improve the accuracy of soil heavy metal mapping, this study proposed an error correction-based multi-fidelity technique to adaptively correct the biases of traditional interpolation methods. The inverse distance weighting (IDW) interpolation method was chosen and combined with the proposed technique to form the adaptive multi-fidelity interpolation framework (AMF-IDW). In AMF-IDW, sampled data were first divided into multiple data groups. Then one data group was used to build the low-fidelity interpolation model through IDW, while the other data groups were treated as high-fidelity data and used for adaptively correcting the low-fidelity model. The capability of AMF-IDW to map the soil heavy metal distribution was evaluated in both hypothetical and real-world scenarios. Results showed that AMF-IDW provided more accurate mapping results compared with IDW and the superiority of AMF-IDW became more evident as the number of adaptive corrections increased. Eventually, after using up all data groups, AMF-IDW improved the R2 values for mapping results of different heavy metals by 12.35-24.32%, and decreased the RMSE values by 30.35%-42.86%, indicating a much higher level of mapping accuracy relative to IDW. The proposed adaptive multi-fidelity technique can be equally combined with other interpolation methods and provide promising potential in improving the soil pollution mapping accuracy.

SERS detection of thiram using polyacrylamide hydrogel-enclosed gold nanoparticle aggregates.

The development of sensitive and long-term signal-stable plasmonic substrates is vital to the in-field application of the surface-enhanced Raman spectroscopy (SERS) technique. The colloidal gold nanoparticles (AuNPs) system is commonly used in SERS detection, but it shows less signal stability and reproducibility due to the uncontrollable aggregation of nanoparticles by adding aggregating agents in SERS detection. In this study, we developed a new SERS detection platform based on polyacrylamide hydrogel-enclosed plasmonic gold nanoparticle aggregates (PAH-AuANs). In the system, the formation of PAH can rapidly stabilize the gold nanoparticle aggregates, avoiding the over-aggregation or precipitation of AuNPs. With the PAH concentration in the range of 6-10 % and AuNPs at the concentration of 0.2 nM, the resulting PAH-AuNAs platform exhibited both sensitive SERS activity and excellent SERS signal stability. The relative standard deviation of the 4-MBA probe SERS signal collected from the PAH-AuNAs platform was lower than 3 %. The limit of detection for the pesticide thiram was down to 0.38 µg/L with a handheld Raman spectrometer. Moreover, the procedure for preparing the PAH-AuNAs platform was easy to handle, offering a new strategy for in-field detection of environmental contaminants with a handheld Raman spectrometer in the future.

Experimental demonstration of counterfactual quantum communication.

Quantum effects, besides offering substantial superiority in many tasks over classical methods, are also expected to provide interesting ways to establish secret keys between remote parties. A striking scheme called "counterfactual quantum cryptography" proposed by Noh [Phys. Rev. Lett. 103, 230501 (2009).] allows one to maintain secure key distributions, in which particles carrying secret information are seemingly not being transmitted through quantum channels. We have experimentally demonstrated, for the first time, a faithful implementation for such a scheme with an on-table realization operating at telecom wavelengths. To verify its feasibility for extension over a long distance, we have furthermore reported an illustration on a 1 km fiber. In both cases, high visibilities of more than 98% are achieved through active stabilization of interferometers. Our demonstration is crucial as a direct verification of such a remarkable application, and this procedure can become a key communication module for revealing fundamental physics through counterfactuals.

Astragaloside IV prevents MPP⁺-induced SH-SY5Y cell death via the inhibition of Bax-mediated pathways and ROS production.

Parkinson's disease (PD) is characterized by a progressive degeneration of dopaminergic neurons in the substantia nigra. Oxidative stress and neural degeneration are suggested to be involved in the pathogenesis of PD. Previous studies have revealed that Astragaloside IV (AS-IV) can reduce inflammation and oxidation, making it a potential therapeutic agent for neurodegenerative disease. In this study, we investigated whether AS-IV protect against 1-methyl-4-phenylpyridnium ion (MPP(+))-induced dopaminergic neurotoxicity in SH-SY5Y cells and determined the mechanism of AS-IV neuroprotection. We found that pretreatment with AS-IV significantly reversed the loss of cell viability, nuclear condensation, the generation of intracellular reactive oxygen species (ROS), and the increase in Bax/Bcl-2 ratio and the activity of caspase-3 induced by MPP(+). Our study suggests that the neuroprotective effect of AS-IV is related to mechanisms including ROS production and the inhibition of Bax-mediated pathway. The present study supports the notion that AS-IV may be a promising neuroprotective agent for the treatment of neurodegenerative disorders such as PD.

Chemoselective cyclization of unprotected linear peptides by α-ketoacid-hydroxylamine amide-ligation.

Cyclic peptides are important synthetic targets due to their constrained conformation, enhanced metabolic stability and improved bioavailability, which combine to make them promising lead compounds for drug candidates. They are typically synthesized by a multi-step sequence of carefully orchestrated protecting group manipulations and cyclization of side-chain protected linear precursors. In the present manuscript we disclose an alternative approach to the synthesis of peptide macrocycles by the α-ketoacid-hydroxylamine (KAHA) ligation. This reaction allows readily prepared linear peptides to be cyclized without reagents or side-chain protecting groups and delivers a native backbone amide bond at the ligation site. The precursors are prepared with Fmoc-based solid phase peptide synthesis using reagents that we have previously disclosed. No post-cyclization manipulations or deprotections other than purification are required. This protocol was applied to five different cyclic peptide natural products of varying ring sizes and side chain functionalities.