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81.
Jonathan Hurtado Dhiraj Acharya Huafang Lai Haiyan Sun Somanath Kallolimath Herta Steinkellner Fengwei Bai Qiang Chen 《Plant biotechnology journal》2020,18(1):266-273
Chikungunya virus (CHIKV) is a mosquito‐transmitted alphavirus, and its infection can cause long‐term debilitating arthritis in humans. Currently, there are no licensed vaccines or therapeutics for human use to combat CHIKV infections. In this study, we explored the feasibility of using an anti‐CHIKV monoclonal antibody (mAb) produced in wild‐type (WT) and glycoengineered (?XFT) Nicotiana benthamiana plants in treating CHIKV infection in a mouse model. CHIKV mAb was efficiently expressed and assembled in plant leaves and enriched to homogeneity by a simple purification scheme. While mAb produced in ?XFT carried a single N‐glycan species at the Fc domain, namely GnGn structures, WT produced mAb exhibited a mixture of N‐glycans including the typical plant GnGnXF3 glycans, accompanied by incompletely processed and oligomannosidic structures. Both WT and ?XFT plant‐produced mAbs demonstrated potent in vitro neutralization activity against CHIKV. Notably, both mAb glycoforms showed in vivo efficacy in a mouse model, with a slight increased efficacy by the ?XFT‐produced mAbs. This is the first report of the efficacy of plant‐produced mAbs against CHIKV, which demonstrates the ability of using plants as an effective platform for production of functionally active CHIKV mAbs and implies optimization of in vivo activity by controlling Fc glycosylation. 相似文献
82.
Jiacheng Hu Shaoya Li Zhaolei Li Huiyuan Li Weibin Song Haiming Zhao Jinsheng Lai Lanqin Xia Dawei Li Yongliang Zhang 《Molecular Plant Pathology》2019,20(10):1463-1474
Plant RNA virus-based guide RNA (gRNA) delivery has substantial advantages compared to that of the conventional constitutive promoter-driven expression due to the rapid and robust amplification of gRNAs during virus replication and movement. To date, virus-induced genome editing tools have not been developed for wheat and maize. In this study, we engineered a barley stripe mosaic virus (BSMV)-based gRNA delivery system for clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9-mediated targeted mutagenesis in wheat and maize. BSMV-based delivery of single gRNAs for targeted mutagenesis was first validated in Nicotiana benthamiana. To extend this work, we transformed wheat and maize with the Cas9 nuclease gene and selected the wheat TaGASR7 and maize ZmTMS5 genes as targets to assess the feasibility and efficiency of BSMV-mediated mutagenesis. Positive targeted mutagenesis of the TaGASR7 and ZmTMS5 genes was achieved for wheat and maize with efficiencies of up to 78% and 48%. Our results provide a useful tool for fast and efficient delivery of gRNAs into economically important crops. 相似文献
83.
Aims
To investigate the interaction effects of diabetes and hypertension on stroke, and also investigate the independent and interaction effects of parental history and environmental factors on diabetes and hypertension in a cross-sectional elderly population.Methods
The Shih-Pai Community Medical Service Program was a community-based, fixed cohort study conducted between June 1999 and November 2002. Socio-demographic and clinical data of subjects aged 65 years and older were collected by well-trained interviewers during home visits. Interaction effects were analyzed using Rothman’s synergy index (SI).Results
In total, 4,124 subjects were included in the study, with 2,284 males and 1,840 females. The synergistic interaction of diabetes and hypertension on stroke was statistically significant in women (SI = 3.16, 95% CI: 1.35–7.39). The synergistic interaction of parental diabetes and being overweight on diabetes was only statistically significant in men, and not in women (SI = 3.30, 95% CI: 1.00–10.83 in men, and SI = 1.15, 95% CI: 0.30–4.39 in women).Conclusions
A synergistic interaction was found for diabetes and hypertension in both sexes when parental history and being overweight were combined. Furthermore, combining diabetes and hypertension in elderly women was significant in terms of the risk of stroke. Strategies to control risk factors in individuals at additional high risk are urgently needed. 相似文献84.
Li S Sang S Pan MH Lai CS Lo CY Yang CS Ho CT 《Bioorganic & medicinal chemistry letters》2007,17(18):5177-5181
Nobiletin, a major component of polymethoxyflavones in citrus fruits, has a broad spectrum of health beneficial properties including anti-inflammatory and anti-carcinogenic activities. The metabolite identification of nobiletin in mouse urine has concluded that it undergoes mono-demethylation (3'- and 4'-demethylnobiletin) and di-demethylation (3',4'-didemethylnobiletin) metabolic pathway. Biological screening of nobiletin and its metabolites has revealed that the metabolites possess more potent anti-inflammatory activity than their parent compound. Therefore, this letter reports the identification of nobiletin metabolites and their anti-inflammatory activity against LPS-induced NO production and iNOS, COX-2 protein expression in RAW264.7 macrophage. 相似文献
85.
While conducting experiments to investigate antimicrobial peptides of amphibians living in the Yunnan-Guizhou region of southwest China, a new family of antimicrobial peptides was identified from skin secretions of the Yunnan frog, Rana pleuraden. Members of the new peptide family named pleurain-As are composed of 26 amino acids with a unique N-terminal sequence (SIIT) and a disulfide-bridged heptapeptide sequence (CRLYNTC). By BLAST search, pleurain-As had no significant similarity to any known peptides. Native and synthetic peptides showed antimicrobial activities against tested microorganisms including Gram-negative and Gram-positive bacteria and fungi. Twenty different cDNAs encoding pleurain-As were cloned from the skin cDNA library of R. pleuraden. The precursors of pleurain-As are composed of 69 amino acid residues including predicted signal peptides, acidic propieces, and cationic mature antimicrobial peptides. The preproregion of pleurain-A precursor comprises a hydrophobic signal peptide of 22 residues followed by an 18 residue acidic propiece which terminates by a typical prohormone processing signal Lys-Arg. The preproregions of precursors are very similar to other amphibian antimicrobial peptide precursors but the mature pleurain-As are different from other antimicrobial peptide families. The remarkable similarity of preproregions of precursors that give rise to very different antimicrobial peptides in distantly related frog species suggests that the corresponding genes form a multigene family originating from a common ancestor. Furthermore, pleurain-As could exert antimicrobial capability against Helicobacter pylori. This is the first report of naturally occurring peptides with anti-H. pylori activity from Rana amphibians. 相似文献
86.
87.
Yong-Ping?ZhengEmail author Timothy?Tin-Yan?Lee Kelly?Ka-Lee?Lai Benjamin?Hon-Kei?Yip Guang-Quan?Zhou Wei-Wei?Jiang James?Chung-Wai?Cheung Man-Sang?Wong Bobby?King-Wah?Ng Jack?Chun-Yiu?Cheng Tsz-Ping?Lam 《Scoliosis》2016,11(1):13
Background
Radiographic evaluation for patients with scoliosis using Cobb method is the current gold standard, but radiography has radiation hazards. Several groups have recently demonstrated the feasibility of using 3D ultrasound for the evaluation of scoliosis. Ultrasound imaging is radiation-free, comparatively more accessible, and inexpensive. However, a reliable and valid 3D ultrasound system ready for clinical scoliosis assessment has not yet been reported. Scolioscan is a newly developed system targeted for scoliosis assessment in clinics by using coronal images of spine generated by a 3D ultrasound volume projection imaging method. The aim of this study is to test the reliability of spine deformity measurement of Scolioscan and its validity compared to the gold standard Cobb angle measurements from radiography in adolescent idiopathic scoliosis (AIS) patients.Methods
Prospective study divided into two stages: 1) Investigation of intra- and inter- reliability between two operators for acquiring images using Scolioscan and among three raters for measuring spinal curves from those images; 2) Correlation between the Cobb angle obtained from radiography by a medical doctor and the spine curve angle obtained using Scolioscan (Scolioscan angle). The raters for ultrasound images and the doctors for evaluating radiographic images were mutually blinded. The two stages of tests involved 20 (80 % females, total of 26 angles, age of 16.4?±?2.7 years, and Cobb angle of 27.6?±?11.8°) and 49 (69 % female, 73 angles, 15.8?±?2.7 years and 24.8?±?9.7°) AIS patients, respectively. Intra-class correlation coefficients (ICC) and Bland-Altman plots and root-mean-square differences (RMS) were employed to determine correlations, which interpreted based on defined criteria.Results
We demonstrated a very good intra-rater and intra-operator reliability for Scolioscan angle measurement with ICC larger than 0.94 and 0.88, respectively. Very good inter-rater and inter-operator reliability was also demonstrated, with both ICC larger than 0.87. For the thoracic deformity measurement, the RMS were 2.5 and 3.3° in the intra- and inter-operator tests, and 1.5 and 3.6° in the intra- and inter-rater tests, respectively. The RMS differences were 3.1, 3.1, 1.6, 3.7° in the intra- and inter-operator and intra- and inter-rater tests, respectively, for the lumbar angle measurement. Moderate to strong correlations (R2?>?0.72) were observed between the Scolioscan angles and Cobb angles for both the thoracic and lumbar regions. It was noted that the Scolioscan angle slightly underestimated the spinal deformity in comparison with Cobb angle, and an overall regression equation y?=?1.1797x (R2?=?0.76) could be used to translate the Scolioscan angle (x) to Cobb angle (y) for this group of patients. The RMS difference between Scolioscan angle and Cobb angle was 4.7 and 6.2°, with and without the correlation using the overall regression equation.Conclusions
We showed that Scolioscan is reliable for measuring coronal deformity for patients with AIS and appears promising in screening large numbers of patients, for progress monitoring, and evaluation of treatment outcomes. Due to it being radiation-free and relatively low-cost, Scolioscan has potential to be widely implemented and may contribute to reducing radiation dose during serial monitoring.88.
Alexander Domnich Donatella Panatto Alessio Signori Piero Luigi Lai Roberto Gasparini Daniela Amicizia 《PloS one》2015,10(5)
BackgroundWeb queries are now widely used for modeling, nowcasting and forecasting influenza-like illness (ILI). However, given that ILI attack rates vary significantly across ages, in terms of both magnitude and timing, little is known about whether the association between ILI morbidity and ILI-related queries is comparable across different age-groups. The present study aimed to investigate features of the association between ILI morbidity and ILI-related query volume from the perspective of age.MethodsSince Google Flu Trends is unavailable in Italy, Google Trends was used to identify entry terms that correlated highly with official ILI surveillance data. All-age and age-class-specific modeling was performed by means of linear models with generalized least-square estimation. Hold-out validation was used to quantify prediction accuracy. For purposes of comparison, predictions generated by exponential smoothing were computed.ResultsFive search terms showed high correlation coefficients of > .6. In comparison with exponential smoothing, the all-age query-based model correctly predicted the peak time and yielded a higher correlation coefficient with observed ILI morbidity (.978 vs. .929). However, query-based prediction of ILI morbidity was associated with a greater error. Age-class-specific query-based models varied significantly in terms of prediction accuracy. In the 0–4 and 25–44-year age-groups, these did well and outperformed exponential smoothing predictions; in the 15–24 and ≥ 65-year age-classes, however, the query-based models were inaccurate and highly overestimated peak height. In all but one age-class, peak timing predicted by the query-based models coincided with observed timing.ConclusionsThe accuracy of web query-based models in predicting ILI morbidity rates could differ among ages. Greater age-specific detail may be useful in flu query-based studies in order to account for age-specific features of the epidemiology of ILI. 相似文献
89.
90.
Duen-Suey Chou George Hsiao Yan-An Lai Yan-Jyu Tsai Joen-Rong Sheu 《Free radical biology & medicine》2009,46(8):1197-1203
In a previous study, we demonstrated that baicalein induces hydroxyl radical formation in human platelets but the mechanisms are unclear. Herein, we show, using an electron spin resonance technique, that baicalein also induces hydroxyl radical formation in B16F10 melanoma cells in a dose-dependent manner. Baicalein produced superoxide anions in the presence of an iron chelator and superoxide dismutase (SOD) inhibitor. We suggest that superoxide anions produced by baicalein were promptly converted to hydroxyl radicals through SOD and the Fenton reaction in B16F10 melanoma cells. According to Western blotting results, the 12-LOX protein was expressed in B16F10 melanoma cells, but baicalein had no effect on 12-LOX expression. Decreases in 12-LOX protein expression and hydroxyl radical signals occurred in a 12-LOX small interfering RNA knockdown protein group compared with the baicalein control. In the MTT assay, we also found that baicalein caused a reduction in cellular viability, which was reversed by the addition of ROS scavengers. On the basis of these data, we conclude that ROS formation catalyzed by 12-LOX is one possible mechanism of growth inhibition by baicalein in B16F10 melanoma cells. 相似文献