NlATG1 Gene Participates in Regulating Autophagy and Fission of Mitochondria in the Brown Planthopper, Nilaparvata lugens

Autophagy plays multiple roles in regulating various physiological processes in cells. However, we currently lack a systematic analysis of autophagy and the autophagy-related gene 1 ATG1 in the brown planthopper (BPH, Nilaparvata lugens), one of the most destructive of the insect pests of rice. In this study, the full-length cDNA of an autophagy-related gene, NlATG1, was cloned from BPH. Real-time qPCR (RT-qPCR) revealed that this NlATG1 gene was expressed differently across developmental stages, at higher levels in nymphs but lower levels in adults. RNA interference with dsNlATG1 significantly decreased the mRNA level of the target gene to 14.6% at day 4 compared with that of the dsGFP control group. The survival of the dsNlATG1-treated group decreased significantly from day 4 onward, dropping to 48.3% on day 8. Examination using transmission electron microscopy (TEM) showed that epithelial cells of the BPH’s midgut in the dsNlATG1-treated group had less autophagic vacuoles than did the dsGFP control, and knockdown of NlATG1 clearly inhibited the starvation-induced autophagy response in this insect. RNA interference of NlATG1 upregulated the NlFis1 gene involved in mitochondrial fission, leading to reductions in mitochondrial width and area. Furthermore, knockdown of NlATG1 also decreased the ATP content and accumulation of glycogen. Together, these results demonstrate that the NlATG1 gene participates in regulating autophagy and fission of mitochondria in the brown planthopper, making it a potentially promising target for pest control given its key role in autophagy, including maintaining the normal structure and function of mitochondria.

[High-intensity focused ultrasound in the treatment of glaucoma]

In recent years, with the improvement of high-intensity focused ultrasound technology, ultrasound cycloplasty has once again gained clinical recognition, becoming one of the non-invasive procedures for glaucoma treatment. Although high-level evidence is still lacking so far, the existing literature has shown that ultrasound cycloplasty can effectively and safely decreases the intraocular pressure in glaucoma by reducing the formation of aqueous humor and increasing the drainage of aqueous humor through the uveoscleral pathway. This article focuses on the efficacy and safety of ultrasound cycloplasty in the treatment of glaucoma, reviews the existing literature, and summarizes the information on the development of equipment, treatment mechanisms, surgical procedures, effectiveness of intraocular pressure reduction, and post-operative complications, with the purpose to provide reference for clinical research and application. (Chin J Ophthalmol, 2020, 56: 66-70).

Association between Skeletal Muscle Strength and Dysphagia among Chinese Community-Dwelling Elderly Adults

OBJECTIVES

Swallowing disorder is a health burden for the elderly in China. This study aimed to investigate the prevalence of dysphagia and to test the association between skeletal muscle strength and swallowing problems among community-dwelling older adults.

DESIGN

A cross-sectional study.

SETTING

Community-dwelling Chinese elderly in China.

PARTICIPANTS

3361 adults aged 65 years or above were involved, among which 1740 (51.8%) were female, with average age of 72.64 (Standard deviation, SD=6.10) years old.

MEASUREMENTS

Handgrip strength (HGS) was used to evaluate skeletal muscle strength. Dysphagia assessment was performed using the Eating Assessment Tool-10 (EAT-10) and the 30mL water swallow test (WST). Binary logistic regression was used to evaluate the relationship between skeletal muscle strength and dysphagia, and covariates as age, gender, material status, etc. were adjusted.

RESULTS

The prevalence of dysphagia were 5.5% and 12.9%, screened by EAT-10 and 30mL WST respectively. Participants with dysphagia showed lower HGS (21.73 ± 9.20 vs. 25.66 ± 11.32, p<0.001, by EAT-10; 20.26 ± 9.88 vs. 26.22 ± 11.28, p<0.001, by WST). The adjusted model suggested that muscle strength is a protective factor for swallowing disorders (adjusted OR=0.974, 95%CI: 0.950-0.999, by EAT-10; adjusted OR=0.952, 95%CI: 0.933-0.972, by WST). Subgroup analyses of WST found the effects were significant among participants aged in 70-74 years group and ≥75 years group, rather than those aged under 70.

CONCLUSION

Dysphagia was significantly associated with skeletal muscle strength among the community-dwelling elderly population. Effective interventions should be taken to manage the decline of muscle strength for the older adults, especially early prevention before 70 years old.

[Gastroenteropancreatic neuroendocrine tumor microenvironment and related therapy]

Neuroendocrine tumor(NET) is a kind of highly heterogeneous and ubiquitous tumor, frequently localized in the gastrointestinal tract and pancreas. Surgery combined with regional ablation, endocrine therapy,chemotherapy and targeted therapy presents a favorable prognosis when treated with G1 or G2 gastroenteropancreatic neuroendocrine tumor(GEP-NET). However, there are only limited therapeutic strategies for metastatic unresectable tumors and poorly differentiated NEC,which are closely related to the special tumor microenvironment of neuroendocrine tumors.Targeting tumor microenvironment therapy is an important method in current systematic therapy, but till now the knowledge of neuroendocrine tumor microenvironment and its related treatment are limited. This article will specifically introduce the characteristics of tumor microenvironment in GEP-NET from the following aspects: the formation of enrichment vascular supply in TME,the role of tumor stroma,immune cells and cancer associacted fibroblast, and immune checkpoint and future trend of immunotherapy.

Multiplicity conversion based on intramolecular triplet-to-singlet energy transfer

The ability to convert between molecular spin states is of utmost importance in materials chemistry. Förster-type energy transfer is based on dipole-dipole interactions and can therefore theoretically be used to convert between molecular spin states. Here, a molecular dyad that is capable of transferring energy from an excited triplet state to an excited singlet state is presented. The rate of conversion between these states was shown to be 36 times faster than the rate of emission from the isolated triplet state. This dyad provides the first solid proof that Förster-type triplet-to-singlet energy transfer is possible, revealing a method to increase the rate of light extraction from excited triplet states.

[Short-term effects of air pollution on lung function of school-age children in Hangzhou]

A total of 1 685 school-age children selected from Hangzhou received lung function testing to evaluate the short-term effects of air pollution on their lung function. The results showed that in every 10 μg/m(3) increase of average concentration of PM(2.5) and PM(10) on the day of the test and the day before the test,peak expiratory flow (PEF) decreased 0.039 (95%CI: 0.012-0.067) L/s and 0.031 (95% CI:0.011-0.051) L/s,respectively. When the average concentration of SO(2) increased 10 μg/m(3) on the day of test and the day prior to the test, PEF and 75% of the forced vital capacity that has not been exhaled (MEF(75)) decreased 0.437 (95%CI: 0.217-0.658) L/s and 0.396 (95%CI: 0.180-0.613) L/s. After being adjusted for NO(2),with every 10 μg/m(3) increase of average concentration of PM(2.5) and PM(10) on the day of the test and the day before the test,PEF and MEF(75) decreased 0.056 (95%CI: 0.028-0.085), 0.053(95%CI: 0.027-0.081) and 0.047 (95%CI: 0.026-0.068) L/s,0.044 (95%CI: 0.023-0.065) L/s on the day before the test, respectively. The results indicate that air pollution have short-term and lag effects on lung function of school-age children in Hangzhou.

[Preliminary efficacy of penetrating canaloplasty in primary angle-closure glaucoma]

Objective: To evaluate the preliminary efficacy and safety of penetrating canaloplasty for treating primary angle-closure glaucoma (PACG). Methods: It is a prospective interventional case series study. Twenty-two patients (24 eyes) with PACG were treated with penetrating canaloplasty (video attached) at the Eye Hospital of Wenzhou Medical University from June 2015 to August 2018. This modified canaloplasty was performed by making a window at the corneal-scleral bed. Aqueous was redirected to the opening of Schlemm's canal after the canaloplasty with intension sutures. Postoperative follow-up was made at 1 day, 7 days, 1 month, 3 months, and 6 months. Surgical success was defined as intraocular pressure (IOP) ≤ 21 mmHg (1 mmHg=0.133 kPa) with glaucoma medication (quantified success) and without any glaucoma medication (complete success). Main outcome measures included IOP, number of medication, surgical success rate, complications, and filtering bleb status. One-way repeated measure ANOVA and rank sum test were used in statistical analysis. Results: Due to the failure of circumferential catheterization of the canal, 4 eyes converted to trabeculectomy. A total of 19 PACG patients (20 eyes) achieved the successful 360-degree catheterization of the canal, including 11 males and 8 females. The mean age was (54±7) years old (range: 41-65 years old), and the mean angle-closure range was (326.3±46.6) degrees. The mean preoperative IOP was (38.0±11.9) mmHg with the median medication number of 3 (range: 2-5). The mean postoperative IOP was (14.5±11.1), (16.1±6.0), (17.7±5.5), (15.7±5.0), and (15.4±3.7) mmHg at 1 day, 7 days, 1 month, 3 months, and 6 months, respectively. There was significant difference in IOP between postoperative and preoperative (all P<0.01). The median medication number (range) was 0 (0-3), 0 (0-2), 0(0-3), 0(0-2), and 0 (0-2) at the 5 time points, respectively. There was significant difference in medication number between postoperative and preoperative (all P<0.01). The quantified success rate was 95%(19/20), and the complete success rate was 90%(18/20) at 6 months. Postoperative complications were observed in 7 eyes (35%) of 20 PACG eyes, including 3 eyes (15%) with hyphema, 2 eyes (10%) with shallow anterior chamber, 1 eye (5%) with Descemet membrane detachment, and 1 eye (5%) with filtration obstruction at the trabeculum ostium. According to the results of slit lamp and ultrasound biomicroscopy examinations, 70% of the eyes (14/20) had no filtering bleb. Eight eyes (40%) with IOP spike were observed. Conclusion: Preliminary study shows penetrating canaloplasty is safe and effective in the treatment of PACG, but needs a longer follow-up. (Chin J Ophthalmol, 2019, 55: 448-453).

Prognostic significance of preoperative radiotherapy in stage II and III rectal cancer patients: A Strobe-compliant study of SEER 18 registries database (1988-2011)

Preoperative radiation therapy has been regarded as the optional neoadjuvant treatment to decrease local recurrence of rectal cancer in addition to surgery. However, its benefit in survival remained obscure. This study was aimed to measure the efficacy of preoperative radiation therapy for survival in stage II and III rectal cancer patients. Retrospective cohort study used the database of Surveillance, Epidemiology and End Results program of the National Cancer Institute in the United States from 1988 to 2011. A total of 49439 patients diagnosed with primary rectal cancer who underwent surgery were included. Clinicopathological characteristics and rectal cancer-specific survival between surgery alone group and surgery plus preoperative radiation therapy group were compared. Rectal cancer patients in surgery plus preoperative radiation therapy group had significantly better survival than those in surgery alone group (72.70% vs. 66.61%, P < 0.001), as well as stratified by stages (stage II: 77.4% vs. 74.3%, P < 0.001; stage III: 68.3% vs. 58.6%, P < 0.001). However, this beneficial impact was only observed after 2000s (P < 0.001). Multivariate survival analysis revealed that preoperative radiation therapy was an independent predictor for better survival in stage III (hazard ratio, 0.795; 95% CI, 0.753-0.840; P < 0.001), but not in stage II (P = 0.70). Preoperative radiation therapy might bring a better survival in stage II and III rectal cancer patients, but only as an independent predictor for stage III patients. As time progressed, preoperative radiation therapy might yield more profit for stage II and III rectal cancer patients.

A puzzling pregnancy epulis with aggressive bone loss mimicking malignant neoplasm: A case report

Epulis is a benign tumor, rarely involves aggressive alveolar bone resorption. This study reported a rare case of rapid growth of pregnancy epulis with extensive alveolar bone destruction and the management of this case. A 24-year old pregnant woman at 35 weeks and 1 day of gestation presented a large asymptomatic nodular mass with severe teeth loosening at the anterior mandibular region for 4 weeks. Radiographic examination showed extensive alveolar bone resorption around the affected teeth to the apical area. After delivery, the patient received an extended resection under general anesthesia. The final histopathological analysis revealed the diagnosis of epulis. In conclusion, the rapid growth of epulis during pregnancy mimicking malignant neoplasm with aggressive alveolar bone destruction was rare and puzzling. In such cases, the histopathological and immunohistochemical examinations are the only effective method to reach the correct diagnosis and clinician should proceed with high precaution.

[Pancreatic ductal adenocarcinoma immune microenvironment and immunotherapy prospects]

The tumor components of pancreatic ductal adenocarcinoma (PDAC) are composed of immune microenvironment of extracellular matrix, fibroblasts, endothelial cells and immune cells together with a minority of malignant cells. The failure of the therapeutic measures, such as chemotherapy, targeted therapy and immunotherapy, has been linked to the specific immune microenvironment of pancreatic cancer. By analyzing the components of immune microenvironment of pancreatic cancer, the mechanism of various components in pancreatic cancer such as highly immunosuppressive, hypoxic and connective tissue hyperplasia can be clarified. New efforts in single-cell profiling will enable a better understanding of the composition of the microenvironment in primary and metastatic PDAC, as well as an understanding of how the microenvironment may respond to novel therapeutic approaches.

Abstract PD5-03: Characterization of high TIL breast cancers reveals a prognostic and functionally distinct tissue-resident memory subpopulation

Background: Tumor infiltrating lymphocytes (TILs) assessed via light microscopy are prognostic and predictive in the early stage and advanced triple negative and HER2-amplified breast cancer (BC). Higher TILs can also identify patients more likely to benefit from anti-PD-1 therapy. In this study we interrogated T cell subsets that comprise high TILs to determine if distinct subpopulations are key mediators of anti-tumor immunity.

Methods: We characterised TILs with a focus on CD3+ T cells in 129 primary and metastatic BC samples using flow cytometry, bulk RNASeq on flow sorted T cell populations, multiplex immunohistochemistry and microdroplet based single cell 3' mRNA sequencing on the 10X Genomics Chromium platform. Cell type specific gene expression signatures were determined from differential expression between putative T cell subpopulations. These signatures were investigated in clinical cohorts, including trial cohorts treated with pembrolizumab.

Results: High TIL Infiltrates consisted primarily of CD3+ T cells, with both CD8 and CD4 populations. Unsupervised clustering of single cell sequencing identified 9 CD8 and CD4 subpopulations with distinct gene expression profiles. In addition to Tregs and CD8 effector memory (TEM) T cells, we found a CD8+ tissue resident memory (TRM) population expressing greater levels of T-cell checkpoints and cytotoxic markers compared to effector memory cells. In 2 primary tumours and 1 liver metastasis, bulk RNASeq of flow sorted TEM and TRM corroborated the single cell mRNASeq results. T cell receptor profiling (TCR) in the 3 samples found non-overlapping repertoires in the 2 primary tumours, but overlap in one metastatic lesion, suggesting divergent developmental origins in the breast, but the potential for nascent TRM differentiation in a metastatic niche. Clustering of these TCRs suggested differing antigen specificities between TRM and non-TRM CD8 T cells. Using Metabric data, the CD8 TRM gene expression signature was prognostic for disease free survival (DFS) in primary TNBCs (n=329, log-rank p=0.003), and was able to further stratify cases with high and low CD8A expression for DFS (log-rank p = 0.03). The CD8 TRM signature was enriched in baseline tumour samples of responders (n = 9) compared with non-responders (n=36) in 45 patients with metastatic melanoma treated with T cell checkpoint blockade (p &lt; 0.0001). Additional single cell sequencing data with TCR sequencing will be combined with these initial results, and an independent data set of single cell mRNASeq and TCR Seq on CD3+ BC TILs will be used to confirm our findings. Cell type specific signatures will be explored in additional clinical cohorts including KEYNOTE-086, and presented at the meeting.

Conclusion: Using single cell profiling of the immune microenvironment in BC we demonstrate that high TIL BCs contain multiple T cell subpopulations with different functional and prognostic significance. Our approach identified a CD8 TRM population with a distinct gene expression profile and strong expression of key immune checkpoints likely representing the presence of true tumor specific immunity. This population may be a key target of immune checkpoint blockade.

Citation Format: Savas P, Virassamy B, Ye C, Salim A, Mintoff CP, Caramia F, Salgado R, Teo ZL, Dushyanthen S, Byrne A, Luen SJ, Fox SB, Speed TP, Mackay LK, Neeson PJ, Loi S. Characterization of high TIL breast cancers reveals a prognostic and functionally distinct tissue-resident memory subpopulation [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD5-03.

Glucocorticoid-induced osteoporosis preventive care in rheumatology patients

Glucocorticoid-induced osteoporosis (GIOP) is common in patients prescribed with long-term glucocorticoids. Guidelines suggest patients receiving moderate-dose glucocorticoid therapy receive GIOP preventive care. Previous studies have shown preventive care rates are not optimal. We look at GIOP preventive care rates in rheumatology patients and predictors of various components of care.

PURPOSE

Glucocorticoid-induced osteoporosis (GIOP) is a common concern in patients prescribed with long-term glucocorticoids. Studies have shown GIOP preventive care is not provided optimally in the general population; however, little is published on GIOP preventive care among patients with rheumatic disease. The objective of this study is to determine the proportion of rheumatology patients who received GIOP preventive care.

METHODS

A population-based retrospective quality assurance study of adults seen at the University of Alberta Rheumatology Clinic was performed using the electronic outpatient medical record. Records of adult patients prescribed with prednisone from January 1st to December 31st, 2016 by a rheumatologist were initially included for review. Those who had been prescribed ≥ 7.5 mg/day for ≥ 3 months were assessed for concurrent GIOP preventive care.

RESULTS

A total of 745 discreet courses of prednisone were prescribed in 433 patients with 113 meeting the above inclusion criteria. Following the prednisone prescription, 79% were taking vitamin D, 86% were taking calcium, and 50% were prescribed with osteoporosis pharmacotherapy. Twenty-five percent of patients had DXA imaging ordered by the rheumatologist within the first 6 months; of these, 86% of patients completed the DXA.

CONCLUSIONS

Overall, our study shows that patients under the care of rheumatologists receive better GIOP preventative care than previously reported care in the general population. However, there is still room for improvement. In particular, men, younger patients, and rural patients seem to be at the most at risk of not receiving optimal GIOP prevention.

Adherence to osteoporosis therapy after an upper extremity fracture: a pre-specified substudy of the C-STOP randomized controlled trial

Despite their proven efficacy for secondary fracture prevention, long-term adherence with oral bisphosphonates is poor.

INTRODUCTION

To compare the effectiveness of two interventions on long-term oral bisphosphonate adherence after an upper extremity fragility fracture.

METHODS

Community-dwelling participants 50 years or older with upper extremity fragility fractures not previously treated with bisphosphonates were randomized to either a multi-faceted patient and physician educational intervention (the active control arm) vs. a nurse-led case manager (the study arm). Primary outcome was adherence (taking > 80% of prescribed doses) with prescribed oral bisphosphonates at 12 months postfracture between groups; secondary outcomes included rates of primary non-adherence and 24-month adherence. We also compared quality of life between adherent and non-adherent patients.

RESULTS

By 12 months, adherence with the initially prescribed bisphosphonate was similar (p = 0.96) in both groups: 38/48 (79.2%) in the educational intervention group vs. 66/83 (79.5%) in the case manager arm. By 24 months, adherence rates were 67% (32/48) in the educational intervention group vs. 53% (43/81) in case managed patients (p = 0.13). Primary non-adherence was 6% (11 patients) in the educational intervention group and 12% (21 patients) in the case managed group (p = 0.07). Prior family history of osteoporosis (aOR 2.1, 95% CI 1.0 to 4.4) and being satisfied with current medical care (aOR 2.3, 95% CI 1.1 to 4.8) were associated with better adherence while lower income (aOR 0.2, 95% CI 0.1 to 0.6, for patients with income < $30,000 per annum) was associated with poorer rates of adherence. There were no differences in health-related quality of life scores at baseline or during follow-up between patients who were adherent and those who were not.

CONCLUSION

While both interventions achieved higher oral bisphosphonate adherence compared to previously reported adherence rates in the general population, primary non-adherence and long-term adherence to bisphosphonates were similar in both arms. Adherence was influenced by family history of osteoporosis, satisfaction with current medical care, and income.

TRIAL REGISTRATION

ClinicalTrials.gov : NCT01401556.

Long-term immunogenicity and immune persistence of live attenuated and inactivated hepatitis a vaccines: a report on additional observations from a phase IV study

Both live attenuated (HA-L) and inactivated (HA-I) hepatitis A vaccine were licensed for routine use in China. Although phase 1, 2 and 3 clinical studies of both vaccines have been completed, further systematic evaluation of their immunogenicity and immunological persistence under phase 4 clinical studies in a wide range of conditions and involving large populations is necessary. A phase IV clinical trial (NCT02601040) was performed in 9000 participants over 18 months of age. Geometric mean concentrations (GMCs) and seroconversion rates (SRs) were compared at five time points during 3 years for 1800 individuals among them. The SRs of HA-L and HA-I were 98.08% (95% CI 95.59%-99.38%) and 99.64% (95% CI 98.93%-100.00%) respectively 28 days after administration of the first dose, and remained at 97.07% (95% CI 94.31%-98.73%) or above and 96.73% (95% CI 94.07%-98.42%) or above respectively during the following 3 years. The GMCs for both the HA-L and HA-I groups showed that both vaccines elicited high anti-HAV titres, considerably more than the threshold of protection needed against HAV infection in humans, and these titres were sustained. Hence, both HA-I and HA-L vaccines could provide an excellent long-term protective effect, and supported the routine use of both vaccines.

[Correlation of transcutaneous oxygen pressure and blood lactate in patients with septic shock]

To analyze the correlation between transcutaneous oxygen pressure (P(tc)O(2)) and blood lactate in patients with septic shock. Fifty-sixpatients with septic shock were prospectively investigated. P(tc)O(2) was monitored continuously for 6 hours, and arterial blood gas was measured at baseline (T0) and 6 hours(T6). Records of P(tc)O(2),were analyzed for the correlation with lactate level and lactate clearance rate. P(tc)O(2) valuesin the high lactate clearance group and the low one were compared.The lowest value of P(tc)O(2) at T6 and duration of P(tc)O(2)<40 mmHg (1 mmHg=0.133 kPa) were both correlated with lactate level and lactate clearance rateat T6.The low predictive value of P(tc)O(2) was 29 mmHg of lactate clearance under 20% with a sensitivity 85.2% and a specificity 65.5%. The low predictive value of P(tc)O(2) in high lactate clearance group was significantly higher than that in low lactate clearance group, while the duration of P(tc)O(2)<40 mmHg was shorter than the latter. During 6 h continuous monitoring, patients with a significant low P(tc)O(2) or prolonged duration of low P(tc)O(2) have relatively high lactate or low lactate clearance after resuscitation.

Topological Reorganization of the Default Mode Network in Severe Male Obstructive Sleep Apnea

Impaired spontaneous regional activity and altered topology of the brain network have been observed in obstructive sleep apnea (OSA). However, the mechanisms of disrupted functional connectivity (FC) and topological reorganization of the default mode network (DMN) in patients with OSA remain largely unknown. We explored whether the FC is altered within the DMN and examined topological changes occur in the DMN in patients with OSA using a graph theory analysis of resting-state functional magnetic resonance imaging data and evaluated the relationship between neuroimaging measures and clinical variables. Resting-state data were obtained from 46 male patients with untreated severe OSA and 46 male good sleepers (GSs). We specifically selected 20 DMN subregions to construct the DMN architecture. The disrupted FC and topological properties of the DMN in patients with OSA were characterized using graph theory. The OSA group showed significantly decreased FC of the anterior-posterior DMN and within the posterior DMN, and also showed increased FC within the DMN. The DMN exhibited small-world topology in both OSA and GS groups. Compared to GSs, patients with OSA showed a decreased clustering coefficient (C_p) and local efficiency, and decreased nodal centralities in the left posterior cingulate cortex and dorsal medial prefrontal cortex, and increased nodal centralities in the ventral medial prefrontal cortex and the right parahippocampal cortex. Finally, the abnormal DMN FC was significantly related to C_p, path length, global efficiency, and Montreal cognitive assessment score. OSA showed disrupted FC within the DMN, which may have contributed to the observed topological reorganization. These findings may provide further evidence of cognitive deficits in patients with OSA.

Reconciling multiple impacts of nitrogen enrichment on soil carbon: plant, microbial and geochemical controls

Impacts of reactive nitrogen (N) inputs on ecosystem carbon (C) dynamics are highly variable, and the underlying mechanisms remain unclear. Here, we proposed a new conceptual framework that integrates plant, microbial and geochemical mechanisms to reconcile diverse and contrasting impacts of N on soil C. This framework was tested using long-term N enrichment and acid addition experiments in a Mongolian steppe grassland. Distinct mechanisms could explain effects of N on particulate and mineral-associated soil C pools, potentially explaining discrepancies among previous N addition studies. While plant production predominated particulate C changes, N-induced soil acidification strongly affected mineral-associated C through decreased microbial growth and pH-sensitive associations between iron and aluminium minerals and C. Our findings suggest that effects of N-induced acidification on microbial respiration and geochemical properties should be included in Earth system models that predict ecosystem C budgets under future N deposition/input scenarios.

Vitellogenin and its receptor play essential roles in the development and reproduction of the brown citrus aphid, Aphis (Toxoptera) citricidus

Vitellogenin (Vg) and its receptor (VgR) play a key role in the reproductive process and development of insects. Aphids are a group of high-fecundity insect species with pseudoplacental viviparity, but the roles of their Vg and VgR genes have not been investigated yet. The brown citrus aphid, Aphis (Toxoptera) citricidus, is a major insect pest of citrus and the main vector of Citrus tristeza closterovirus. In this study, we identified and characterized these two genes, designated as AcVg and AcVgR, from the brown citrus aphid. We found that AcVg has lost the DUF1943 domain that is present in other insect Vgs. Silencing of AcVg and AcVgR led to a delay in the nymph-adult transition, a prolonged prereproductive period, and a shortened reproductive period, which in turn resulted in slower embryonic development and fewer new-born nymphs. Interestingly, silencing of AcVg decreased the transcript level of AcVgR, but silencing of AcVgR resulted in increased transcript levels of AcVg. In addition, silencing of Vg/VgR had similar phenotypes between alate and apterous morphs, suggesting that the functions of these two genes are the same in the two wing morphs of the aphid. Our results demonstrate that Vg and VgR are involved in various aspects of aphid development and reproduction. Further studies on the synthesis of Vg could help to elucidate the reproductive mechanism and provide information that will be useful for developing new pest control strategies.