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BACKGROUND The brown planthopper (BPH), Nilaparvata lugens, is the most destructive rice insect pest. To exploit potential target genes for applications in transgenic rice to control this sap‐sucking insect pest, three ferritin genes were functionally characterized in this study. RESULTS: In this study, three ferritin genes, that is, ferritin 1 Heavy Chain (NlFer1), ferritin 2 Light Chain (NlFer2) and soma ferritin (Nlsoma‐Fer), were identified from BPH. Tissue‐specific analyses showed that all three genes were highly expressed in the gut. Although double‐stranded RNA injection‐mediated RNA inference (RNAi) of Nlsoma‐Fer expression resulted in only < 14% mortality in BPH, knockdown of NlFer1 or NlFer2 led to retarded growth and 100% mortality in young nymphs, and downregulation of NlFer1 and NlFer2 in newly emerged female adults caused undeveloped ovaries and severely inhibited oocyte growth, resulting in extremely low fecundity and a zero hatching rate. Knockdown of NlFer1 and NlFer2 caused similar phenotypes in BPH, indicating that they function together, as in many other animals. The results demonstrated that NlFer1 and NlFer2 were essential for BPH development and reproduction. BPHs showed high sensitivity to both dsNlFer1 and dsNlFer2, and injection of only 0.625 ng dsNlFer1 per BPH resulted in 100% mortality. Additionally, the effectiveness of feeding dsNlFer1 and dsNlFer2 to BPH nymphs was further proven. CONCLUSION: NlFer1 and NlFer2 are essential for BPH development and reproduction, and the insect is highly sensitive to their depletion, suggesting that the two gut‐highly‐expressed genes are promising candidates for application in RNAi‐based control of this destructive pest. [ABSTRACT FROM AUTHOR]

Vitellogenin (Vg) is precursor of vitellin. Here, we identified a Vg (NlVg) and two Vg -likes (NlVg -like1 and NlVg -like2) in the brown planthopper, Nilaparvata lugens. Phylogenetic analyses showed that NlVg-like1 and NlVg-like2 are not clustered with the conventional insect Vgs associated with vitellogenesis. Temporo-spatial expression analyses showed that the NlVg and NlVg -like2 transcript levels increased significantly 24 h after emergence and were primarily expressed in female adults. However, NlVg -like1 was expressed during all stages, and in both genders. Tissue-specific analyses showed that all three genes were most highly expressed in the fat body. The injection of double-stranded RNA targeting NlVg showed that NlVg is essential not only for oocyte development but also for nymph development. The knockdown of NlVg -like1 in female adults resulted in failure to hatch or death before eggshell emergence in 18% of offspring embryos, suggesting that NlVg -like1 plays an important role during late embryogenesis. Approximately 65% of eggs laid by females that were treated with double-stranded RNA targeting NlVg -like2 failed to hatch, indicating that NlVg -like2 plays a role in nutrition absorption during oocyte, or embryonic development. Our results illustrate the structural and functional differences among the Vg and Vg -like genes and provide potential targets for RNA-interference-based insect pest management strategies. [ABSTRACT FROM AUTHOR]

Chronic lead (Pb) exposure causes cognitive deficits. This study aimed to explore the neuroprotective effect and mechanism of β-asarone, an active component from Chinese Herbs Acorus tatarinowii Schott, to alleviate impairments of spatial memory and synaptogenesis in Pb-exposed rats. Both Sprague-Dawley developmental rat pups and adult rats were used in the study. Developmental rat pups were exposed to Pb throughout the lactation period and β-asarone (10, 40mg kg-1, respectively) was given intraperitoneally from postnatal day 14 to 21. Also, the adult rats were exposed to Pb from embryo stage to 11 weeks old and β-asarone (2.5, 10, 40mg kg-1, respectively) was given from 9 to 11 weeks old. The level of β-asarone in brain tissue was measured by High Performance Liquid Chromatography. The Morris water maze test and Golgi-Cox staining method were used to assess spatial memory ability and synaptogenesis. The protein expression of NR2B subunit of NMDA receptor, Activity-regulated cytoskeleton-associated protein (Arc/Arg3.1) and Wnt family member 7A (Wnt7a) in hippocampus, as well as mRNA expression of Arc/Arg3.1 and Wnt7a, was also explored. We found that β-asarone could pass through the blood brain barrier quickly. And β-asarone effectively attenuated Pb-induced reduction of spine density in hippocampal CA1 and dentate gyrus areas in a dose-dependent manner both in developmental and adult rats, meanwhile the Pb-induced impairments of learning and memory were partially rescued. In addition, β-asarone effectively up-regulated the protein expression of NR2B, Arc and Wnt7a, as well as the mRNA levels of Arc/Arg3.1 and Wnt7a, which had been suppressed by Pb exposure. The results suggest the neuroprotective properties of β-asarone against Pb-induced memory impairments, and the effect is possibly through the regulation of synaptogenesis, which is mediated via Arc/Arg3.1 and Wnt pathway. [ABSTRACT FROM AUTHOR]

Oviducts are the "traffic hubs" of the female reproductive system, serving as the crucial conduits for egg transportation. By performing LC–MS/MS proteomic detection together with transcriptomic analysis, 80 lateral oviduct-secreted proteins were identified, and 5 genes (NlOdsp , NlOdsp1 , NlOdsp2 , NlOdsp3 and NlOdsp 4) specifically expressed in the oviducts of the brown planthopper Nilaparvata lugens, the most destructive rice pest, were authenticated. qRT–PCR analysis revealed that these genes and proteins were mainly/specifically expressed in the female reproductive system in adulthood. RNA interference (RNAi) against the 5 NlOdsp genes significantly affected the survival rates (3.4% - 68.7% of the control) and fecundities of female adults (3.9% - 57.6% of the control) at 8 d post injection (p.i.). In addition, the lack of NlOdsp1 caused decreases in the gel-like brown secretions inside the lateral oviducts, while increased secretions were found in the ds NlOdsp2- treated groups. In addition, NlOdsp3 is a pleiotropic gene involved in both oocyte development and egg movement through the lateral oviducts, similar to the role of NlOdsp in egg transportation. The results deepen our understanding of oviduct-secreted proteins in female insects and provide novel target genes for RNAi-based insect pest control. Oviduct plays a vital role in animal reproductive processes and it serves as the crucial conduit for egg transportation. Though oviduct secretes have been well documented in high animals, the proteomic information of insect oviduct secretes remains poorly understood. The present study revealed 80 oviduct secreted proteins, including 19 unknown proteins, from the rice planthopper, the most destructive rice pest which lay eggs in plant tissues. Five of the 19 proteins were further functionally characterized. The results not only deepen our understanding of the oviduct secreted proteins in insect reproductive biology, but also provide basis for interaction between insects and host plants, and provide novel target genes for RNAi-based insect pest control. [Display omitted] • An integrative landscape of the oviduct-secreted proteome of the brown planthopper is presented. • Five oviduct-secreted proteins were confirmed to be lateral oviduct-specific. • Five oviduct-secreted proteins play important roles in survival, reproduction and egg transportation. [ABSTRACT FROM AUTHOR]

The oviduct serves as a delivery tube for mature eggs ovulated from ovaries to egg-laying sites. Oviduct secreted components play important roles in ovulation and fertilization in mammals, however, no oviduct secreted protein has been characterized in an insect to date. Here, we identified a gene highly expressed in the lateral oviduct of the adult females in the brown planthopper (BPH), Nilaparvata lugens , the most destructive rice insect pest. Western blotting and immunofluorescence analyses revealed that the gene encodes a protein that is specifically expressed in the lateral oviduct as a component of the gel-like material secreted by the oviduct epithelial cells into the lumen of the swollen part of the lateral oviducts. The protein was tentatively named N. lugens oviduct secreted protein (Nlodsp). RNA interference (RNAi) against NlOdsp transcripts caused a failure of the lateral oviducts to deliver oocytes to the common oviduct that was, by consequence, plugged by 1–2 oocytes. Moreover, although oocytes in the Nlodsp-deficient ovariole were not released to the oviduct, they continued to develop, finally resulting in the presence of several matured oocytes in an ovariole. These defects evidently declined female fecundity. Together, our results demonstrate that NlOdsp plays an essential role in egg transport through the oviduct during ovulation. This work deepens our understanding of insect reproductive system and provides a potential target gene for RNAi-based insect pest control. [Display omitted] • An oviduct secreted protein (NlOdsp) firstly characterized in an insect. • NlOdsp specifically expressed in the lateral oviduct and secreted into its lumen. • Knockdown of NlOdsp caused a failure of the lateral oviducts to deliver oocytes to the common oviduct. • NlOdsp plays an essential role in egg transport through the oviduct during ovulation. [ABSTRACT FROM AUTHOR]

Background: At present, the infection and prevalence rates of tuberculosis (TB) are still high in worldwide. The Xpert MTB/RIF technology has improved the diagnosis speed of Mycobacterium tuberculosis (MTB) and facilitated the rapid treatment of TB patients., Methods: We searched experimental data derived from Xpert MTB/RIF for detecting MTB in gastric aspirates in PubMed, Embase, Web Of Science, and the Cochrane Library databases between January 2012 to April 2019. A summary receiver operating characteristic curve (SROC curve) was used to analyze the pooled sensitivity, pooled specificity, PLR, NLR, and DOR for determining the accuracy of the test., Results: Our database search resulted in 10 relevant articles. The pooled sensitivity of Xpert MTB/RIF for detecting TB in GA was 86% (95% CI, 83-89%), and I2 = 93.4%. The pooled specificity was 92% (95% CI, 90-93%) and I2 = 97.8%. In addition, the positive LR was 12.12 (95% CI, 5.60-26.21), negative LR was 0.20 (95% CI, 0.11-0.36), and the diagnostic odds ratio (DOR) was 147.04 (95% CI, 37.20-581.19). Using the SROC curve, the AUC was 0.9730 and Q* was 0.9248 (SE = 0.0261). The publication bias was P=0.517 (P>0.05)., Conclusions: The Xpert MTB/RIF for detecting MTB in gastric aspirates was highly accurate. In addition, we observed that the publication bias in the present study was low. Hence, the Xpert MTB/RIF technology is highly accurate and has the advantage of rapid testing for MTB in clinical samples., (© 2020 The Author(s).)

Background: Tuberculous meningitis (TBM) is one of the most serious types of extrapulmonary tuberculosis. However, low sensitivity of culture of cerebrospinal fluid (CSF) increases the difficulty in clinical diagnosis, leading to diagnostic delay, and misdiagnosis. Xpert MTB/RIF assay is a rapid and simple method to detect tuberculosis. However, the efficacy of this technique in diagnosing TBM remains unclear. Therefore, a meta-analysis was conducted to evaluate the diagnostic efficacy of Xpert MTB/RIF for TBM, which may enhance the development of early diagnosis of TBM., Methods: Relevant studies in the PubMed, Embase, and Web of Science databases were retrieved using the keywords 'Xpert MTB/RIF', 'tuberculous meningitis (TBM)'. The pooled sensitivity, pooled specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, summary receiver operator characteristic curve, and area under the curve (AUC) of Xpert MTB/RIF were determined and analyzed., Results: A total of 162 studies were enrolled and only 14 met the criteria for meta-analysis. The overall pooled sensitivity of Xpert MTB/RIF was 63% [95% confidence interval (CI), 59-66%], while the overall pooled specificity was 98.1% (95% CI, 97.5-98.5%). The pooled values of positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 20.91% (12.71-52.82%), 0.40% (0.32-0.50%), and 71.49% (32.64-156.56%), respectively. The AUC was 0.76., Conclusions: Xpert MTB/RIF exhibited high specificity in diagnosing TBM in CSF samples, but its sensitivity was relatively low. It is necessary to combine other high-sensitive detection methods for the early diagnosis of TBM. Moreover, the centrifugation of CSF samples was found to be beneficial in improving the sensitivity., (© 2020 The Author(s).)

Purpose: Although vitamin D inhibits pancreatic cancer proliferation in laboratory models, the association of plasma 25-hydroxyvitamin D [25(OH)D] with patient survival is largely unexplored., Patients and Methods: We analyzed survival among 493 patients from five prospective US cohorts who were diagnosed with pancreatic cancer from 1984 to 2008. We estimated hazard ratios (HRs) for death by plasma level of 25(OH)D (insufficient, < 20 ng/mL; relative insufficiency, 20 to < 30 ng/mL; sufficient ≥ 30 ng/mL) by using Cox proportional hazards regression models adjusted for age, cohort, race and ethnicity, smoking, diagnosis year, stage, and blood collection month. We also evaluated 30 tagging single-nucleotide polymorphisms in the vitamin D receptor gene, requiring P < .002 (0.05 divided by 30 genotyped variants) for statistical significance., Results: Mean prediagnostic plasma level of 25(OH)D was 24.6 ng/mL, and 165 patients (33%) were vitamin D insufficient. Compared with patients with insufficient levels, multivariable-adjusted HRs for death were 0.79 (95% CI, 0.48 to 1.29) for patients with relative insufficiency and 0.66 (95% CI, 0.49 to 0.90) for patients with sufficient levels (P trend = .01). These results were unchanged after further adjustment for body mass index and history of diabetes (P trend = .02). The association was strongest among patients with blood collected within 5 years of diagnosis, with an HR of 0.58 (95% CI, 0.35 to 0.98) comparing patients with sufficient to patients with insufficient 25(OH)D levels. No single-nucleotide polymorphism at the vitamin D receptor gene met our corrected significance threshold of P < .002; rs7299460 was most strongly associated with survival (HR per minor allele, 0.80; 95% CI, 0.68 to 0.95; P = .01)., Conclusion: We observed longer overall survival in patients with pancreatic cancer who had sufficient prediagnostic plasma levels of 25(OH)D., Competing Interests: Authors’ disclosures of potential conflicts of interest are found in the article online at www.jco.org. Author contributions are found at the end of this article., (© 2016 by American Society of Clinical Oncology.)

Objective: To investigate the relationship between serum bilirubin and carotid atherosclerosis in patients with hypertension., Patients and Methods: Carotid artery ultrasonography was performed in 198 patients (104 males, average age of 65.6+/-7.1 years) with hypertension. Serum levels of bilirubin and C-reactive proteins (CRP) were measured at the same time., Results: Carotid atherosclerosis was detected in 133 patients, 87 of them had carotid artery plaque. The prevalence of stroke (20.3%) and myocardial infarction (13.5%) in the atherosclerosis group was higher than in the non-atherosclerosis group (9.2% and 6.2%, respectively, p<0.05). The average total serum bilirubin in the atherosclerosis group was lower than in the non-atherosclerosis group (12.8+/-1.3 vs 16.8+/-1.5 micromol/L, p<0.01), whereas the average serum of CRP was higher (4.1+/-1.1 vs 2.3+/-0.7 mg/L, p<0.01). After adjusting other factors such as age, total cholesterol, diabetes and systolic blood pressure, total serum bilirubin was negatively associated with carotid atherosclerosis in women and men, with odds ratios of 0.49 (95% CI, 0.28 to 0.71; p<0.01) and 0.66 (95% CI, 0.46 to 0.80; p<0.01). Serum CRP was positively correlated to carotid atherosclerosis, with odds ratios of 1.76 (95% CI, 1.36 to 2.04; p<0.01) in women and 1.95 (95% CI, 1.46 to 2.82; p<0.01) in men., Conclusion: Carotid atherosclerosis was associated with a high prevalence of stroke or myocardial infarction in hypertensive patients. Serum bilirubin was negatively associated with carotid atherosclerosis.