Accurate and High-Resolution Particle Mass Measurement Using a Peak Filtering Algorithm.

Charge detection quadrupole ion trap mass spectrometry (CD-QIT MS) is an effective way of achieving the mass analysis of microparticles with ultrahigh mass. However, its mass accuracy and resolution are still poor. To enhance the performance of CD-QIT MS, the resolution Rpeak of each peak in the mass spectra resulting from an individual particle was assessed, and a peak filtering algorithm that can filter out particle adducts and clusters with a lower Rpeak was proposed. By using this strategy, more accurate mass information about the analyzed particles could be obtained, and the mass resolution of CD-QIT MS was improved by nearly 2-fold, which was demonstrated by using the polystyrene (PS) particle size standards and red blood cells (RBCs). Benefiting from these advantages of the peak filtering algorithm, the baseline separation and relative quantification of 3 and 4 µm PS particles were achieved. To prove the application value of this algorithm in a biological system, the mass of yeast cells harvested at different times was measured, and it was found that the mixed unbudded and budded yeast cells, which otherwise would not be differentiable, were distinguished and quantified with the algorithm.

Spinal cord stimulation for postural abnormalities in Parkinson's disease: 1-year prospective pilot study.

BACKGROUND: Postural abnormalities (PA) are common in the advanced stages of Parkinson's disease (PD), but effective therapies are lacking. A few studies suggested that spinal cord stimulation (SCS) could be a potential therapy whereas its effect is still uncertain. We aimed to investigate whether SCS had potential for benefiting PD patients with PA. METHODS: T8-12 SCS was operated on six PD patients with PA and all patients were followed for one year. Evaluations were made before and after SCS. Moreover, three patients were tested separately with SCS on-state and off-state to confirm the efficacy of SCS. RESULTS: Improvements in lateral trunk flexion degree, anterior thoracolumbar flexion degree and motor function were found after SCS. The improvements diminished while SCS was turned off. CONCLUSIONS: Lower thoracic SCS may be effective for improving PA in PD patients, but further studies are needed to confirm this conclusion. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1900024326, Registered on 6th July 2019; https://www.chictr.org.cn/showproj.aspx?proj=40835 .

Risk and aversion coding in human habenula high gamma activity.

Neurons in the primate lateral habenula fire in response to punishments and are inhibited by rewards. Through its modulation of midbrain monoaminergic activity, the habenula is believed to play an important role in adaptive behavioural responses to punishment and underlie depressive symptoms and their alleviation with ketamine. However, its role in value-based decision-making in humans is poorly understood due to limitations with non-invasive imaging methods which measure metabolic, not neural, activity with poor temporal resolution. Here, we overcome these limitations to more closely bridge the gap between species by recording local field potentials directly from the habenula in 12 human patients receiving deep brain stimulation treatment for bipolar disorder (n = 4), chronic pain (n = 3), depression (n = 3) and schizophrenia (n = 2). This allowed us to record neural activity during value-based decision-making tasks involving monetary rewards and losses. High-frequency gamma (60-240 Hz) activity, a proxy for population-level spiking involved in cognitive computations, increased during the receipt of loss and decreased during receipt of reward. Furthermore, habenula high gamma also encoded risk during decision-making, being larger in amplitude for high compared to low risk. For both risk and aversion, differences between conditions peaked approximately between 400 and 750 ms after stimulus onset. The findings not only demonstrate homologies with the primate habenula but also extend its role to human decision-making, showing its temporal dynamics and suggesting revisions to current models. The findings suggest that habenula high gamma could be used to optimize real-time closed-loop deep brain stimulation treatment for mood disturbances and impulsivity in psychiatric disorders.

Adding injury to insult: Unfair treatment at work and occupational injury among hospital patient-care workers.

BACKGROUND: Hospital patient-care workers have high occupational injury rates. While physical hazards within hospital work environments are established determinants of injury, social exposures may also contribute. This study examined how reports of unfair treatment at work, a dimension of work-related experiences of discrimination, were associated with injury among hospital-based patient-care workers. METHODS: We used data from the Boston Hospital Workers Health Study, a longitudinal cohort of nurses and nursing assistants at two Boston-area hospitals. In 2018, we conducted a worker survey asking about three types of unfair treatment at work and occupational injuries during the past year. We used mixed-effects logistic regression models to evaluate associations between specific types, total load, and high-frequency exposure of unfair treatment with injury, adjusting for age, gender, race and ethnicity, job title, and unit type. RESULTS: Among 1001 respondents, 21% reported being humiliated in front of others at work, 28% reported being watched more closely than other workers, and 47% reported having to work twice as hard as others for the same treatment. For each type of unfair treatment, we observed a monotonic relationship with occupational injury wherein increasing frequency of exposure was associated with increased odds of injury. We also observed monotonic relationships between total load and high-frequency exposure to unfair treatment and odds of injury. CONCLUSIONS: Work-related unfair treatment is associated with injury among hospital workers. Programs and policies that focus on preventing unfair treatment may lessen injury burden in hospital workers.

Pocket-Size Wireless Nanoelectrospray Ionization Mass Spectrometry for Metabolic Analysis of Salty Biofluids and Single Cells.

Analysis of volume-limited biological samples such as single cells and biofluids not only benefits clinical purposes but also promotes fundamental research in life sciences. Detection of these samples, however, imposes strict requirements on measurement performance because of the minimal volume and concentrated salts of the samples. Herein, we developed a self-cleaning nanoelectrospray ionization device powered by a pocket-size "MasSpec Pointer" (MSP-nanoESI) for metabolic analysis of salty biological samples with limited volume. The self-cleaning effect induced by Maxwell-Wagner electric stress helps with keeping the borosilicate glass capillary tip free from clogging and thus increasing salt tolerance. This device possesses a high sample economy (about 0.1 µL per test) due to its pulsed high voltage supply, sampling method (dipping the nanoESI tip into analyte solution), and contact-free electrospray ionization (ESI) (the electrode does not touch the analyte solution during ESI). High repeatable results could be acquired by the device with a relative standard deviation (RSD) of 1.02% for voltage output and 12.94% for MS signals of caffeine standard. Single MCF-7 cells were metabolically analyzed directly from phosphate buffered saline, and two types of untreated cerebrospinal fluid from hydrocephalus patients were distinguished with 84% accuracy. MSP-nanoESI gets rid of the bulky apparatus and could be held in hand or put into one's pocket for transportation, and it could operate for more than 4 h without recharge. We believe this device will boost scientific research and clinical usage of volume-limited biological samples with high-concentration salts in a low-cost, convenient, and rapid manner.

Globus pallidus internus versus subthalamic nucleus deep brain stimulation for isolated dystonia: A 3-year follow-up.

BACKGROUND AND PURPOSE: Bilateral deep brain stimulation (DBS) surgery targeting the globus pallidus internus (GPi) or the subthalamic nucleus (STN) is widely used in medication-refractory dystonia. However, evidence regarding target selection considering various symptoms remains limited. This study aimed to compare the effectiveness of these two targets in patients with isolated dystonia. METHODS: This retrospective study evaluated 71 consecutive patients (GPi-DBS group, n = 32; STN-DBS group, n = 39) with isolated dystonia. Burke-Fahn-Marsden Dystonia Rating Scale scores and quality of life were evaluated preoperatively and at 1, 6, 12, and 36 months postoperatively. Cognition and mental status were assessed preoperatively and at 36 months postoperatively. RESULTS: Targeting the STN (STN-DBS) yielded effects within 1 month (65% vs. 44%; p = 0.0076) and was superior at 1 year (70% vs. 51%; p = 0.0112) and 3 years (74% vs. 59%; p = 0.0138). For individual symptoms, STN-DBS was preferable for eye involvement (81% vs. 56%; p = 0.0255), whereas targeting the GPi (GPi-DBS) was better for axis symptoms, especially for the trunk (82% vs. 94%; p = 0.015). STN-DBS was also favorable for generalized dystonia at 36-month follow-up (p = 0.04) and required less electrical energy (p < 0.0001). Disability, quality of life, and depression and anxiety measures were also improved. Neither target influenced cognition. CONCLUSIONS: We demonstrated that the GPi and STN are safe and effective targets for isolated dystonia. The STN has the benefits of fast action and low battery consumption, and is superior for ocular dystonia and generalized dystonia, while the GPi is better for trunk involvement. These findings may offer guidance for future DBS target selection for different types of dystonia.

Diazo-reaction based dual-mode colorimetric-electrochemical sensing of nitrite in pickled food.

Development of an effective and convenient sensor for sensitive detection of nitrites is of great concern since excessive amounts of nitrites can be harmful to both human health and the environment. In this work, Cu-MOF modified exfoliated graphite paper (EGP) was employed as a signal reporter to enable the visual and electrochemical dual-mode sensing of nitrites. Cu-MOFs were in situ synthesized on EGP, which exhibited an excellent oxidase enzyme-like activity to oxidize 3,3',5,5'-tetramethylbenzidine (TMB) into its oxidation product (oxTMB). The multi-layer structure and the superior electrical conductivity of EGP not only facilitated the loading of the Cu-MOF nanozyme for colorimetric sensing but also enabled its use as an underlying backbone to support electroanalysis. Based on the recognition of nitrite through a highly specific diazo reaction between nitrite and oxTMB, the addition of nitrite caused the colorimetric sensing solution to change color from blue to green, which allowed for the colorimetric sensing of nitrite with a limit of detection (LOD) of 8.5 × 10-6 mol L-1. Meanwhile, the Cu-MOF/EGP electrochemical platform was employed for ratiometric detection of nitrite based on the electrochemical oxidation of nitrite and TMB. Compared with the colorimetric mode, the electrochemical mode possessed higher sensitivity with a LOD of 5.4 × 10-7 mol L-1, indicating the high sensitivity and accuracy of the proposed dual-mode sensing strategy. Furthermore, the determination of nitrite in different pickled food samples is demonstrated.

The H3K36me2 methyltransferase NSD1 modulates H3K27ac at active enhancers to safeguard gene expression.

Epigenetics, especially histone marks, functions beyond the DNA sequences to regulate gene expression. Depletion of NSD1, which catalyzes H3K36me2, leads to both up- and down-regulation of gene expression, indicating NSD1 is associated with both active and repressed gene expression. It's known that NSD1 regulates the deposition and expansion of H3K27me3, a repressive mark for gene expression, to keep active gene transcription. However, how NSD1 functions to repress gene expression is largely unknown. Here, we find that, when NSD1 is knocked out in mouse embryonic stem cells (mESCs), H3K27ac increases correlatively with the decrease of H3K36me2 at active enhancers, which is associated with mesoderm differentiation genes, leading to elevated gene expression. Mechanistically, NSD1 recruits HDAC1, the deacetylase of H3K27ac, to chromatin. Moreover, HDAC1 knockout (KO) recapitulates the increase of H3K27ac at active enhancers as the NSD1 depletion. Together, we propose that NSD1 deposits H3K36me2 and recruits HDAC1 at active enhancers to serve as a 'safeguard', preventing further activation of active enhancer-associated genes.

Utilizing biochar to decorate nanoscale FeS for the highly effective decontamination of Se(IV) from simulated wastewater.

Selenium (Se) as an essential nutrient for human beings at trace concentrations, the allowable concentration for the human is only 40 µg/L. Iron sulfide (FeS) nanoparticles have been applied for excessive of selenium (Se) remediation in surface water and groundwater. In this study, FeS nanoparticles were anchored onto biochar (BC) to reduce agglomeration of FeS and prepared into the composite of FeS-BC by pyrolysis to economically and efficiently remove Se(IV) from simulated wastewater based on the excellent performance of FeS and the low cost of BC. Characterizations presented the uniform anchorage of FeS on the BC surface to prevent agglomeration. The results of batch experiments revealed that the removal of Se(IV) by FeS-BC nanomaterials significantly depended on the pH value, with the maximum removal of ∼174.96 mg/g at pH 3.0. A pseudo-second-order kinetic model well reflected the kinetic removal of Se(IV) in pure Se(IV) solution with different concentration, as well as the coexistence of K+, Ca2+, Cl-, and SO42- ions. The presence of K+ ions significantly inhibited the removal of Se(IV) with the increase of K+ ion concentration compared with the effect of the other three ions. SEM-EDS and XPS analyses indicated that the removal process was achieved through adsorption by surface complexation, and reductive precipitation of Se(IV) into Se0 with the electron donor of Fe(II) and S(-II) ions. The FeS-BC nanomaterial exhibited an excellent application prospect in the remediation of Se(IV).

Predicting the onset of freezing of gait in Parkinson's disease.

BACKGROUND: Freezing of gait is a debilitating symptom of Parkinson's disease associated with high risks of falls and poor quality of life. While productive therapy for FoG is still underway, early prediction of FoG could help high-risk PD patients to take preventive measures. In this study, we predicted the onset of FoG in de novo PD patients using a battery of risk factors from patients enrolled in PPMI cohort. METHODS: Baseline characteristics were compared between subjects who developed FoG (68 patients, 37.2%, pre-FoG group) during the five-year follow up and subjects who did not (115 patients, 62.8%, non-FoG group). A multivariate logistic regression model was built based on backward stepwise selection of factors that were associated with FoG onset in the univariate analysis. ROC curves were used to assess sensitivity and specificity of the predictive model. RESULTS: At baseline, age, PIGD score, cognitive functions, autonomic functions, sleep behavior, fatigue and striatal DAT uptake were significantly different in the pre-FoG group relative to the non-FoG group. However, there was no difference in genetic characteristics between the two patient sets. Univariate analysis showed several motor and non-motor factors that correlated with FoG, including PIGD score, MDS-UPDRS part II score, SDMT score, HVLT Immediate/Total Recall, MOCA, Epworth Sleepiness Scale, fatigue, SCOPA-AUT gastrointestinal score, SCOPA-AUT urinary score and CSF biomarker Abeta42. Multivariate logistic analysis stressed that high PIGD score, fatigue, worse SDMT performance and low levels of Abeta42 were independent risk factors for FoG onset in PD patients. CONCLUSIONS: Combining motor and non-motor features including PIGD score, poor cognitive functions and CSF Abeta can identify PD patients with high risk of FoG onset.

Multifunctional Metal-Organic Framework as a Versatile Nanoplatform for Aß Oligomer Imaging and Chemo-Photothermal Treatment in Living Cells.

In view of the close association of ß-amyloid oligomers (AßO) with the clinical development of Alzheimer's disease (AD) symptoms, it is urgent to design a promising sensing and therapeutic strategy that can target AßO for preventing or delaying the onset of AD. Herein, a core-shell nanocomposite CeONP-Res-PCM@ZIF-8/polydopamine (PDA) was synthesized through an in situ encapsulated strategy, in which resveratrol (Res), ceria nanoparticles (CeONPs), and PCM (tetradecanol) were embedded into the ZIF-8/PDA matrix via a water-based mild approach. Using the AßO aptamer, the ability of CeONP-Res-PCM@ZIF-8/PDA/Apt as the fluorescent sensing platform for AßO detection and intracellular imaging was demonstrated. The nanocomposite was high in Res loading (27.5%) and could be activated to release the encapsulated Res upon illumination with NIR through PCM regulation. Moreover, due to the synergetic interactions of PDA, CeONPs, and Res in one system, CeONP-Res-PCM@ZIF-8/PDA/Apt nanocomposites exhibited multifunctional effects on inhibiting Aß aggregation, degrading Aß fibrils, and alleviating Aß-induced oxidative stress and neural apoptosis. These therapeutic effects could be enhanced under NIR irradiation by virtue of the excellent photothermal property of PDA. As far as we know, there is no report of using ZIF-8-based materials for simultaneous sensing and therapeutic applications. This work boosted the development of multifunctional nanoagents for biomedical research studies.

Utility of Deep Brain Stimulation Telemedicine for Patients With Movement Disorders During the COVID-19 Outbreak in China.

OBJECTIVE: To explore the utility of deep brain stimulation (DBS) telemedicine in the management of patients with movement disorders from January 2019 to March 2020, covering the main period of the COVID-19 outbreak in China. MATERIALS AND METHODS: We obtained data from 40 hospitals around China that employed DBS tele-programming for their outpatients with Parkinson's disease or dystonia from January 2019 to March 2020. Data were obtained on the number and nature of patients' DBS health care service requests, reasons for their requests, the number of DBS telemedicine sessions subsequently completed, safety issues, and the patients' satisfaction with the DBS tele-programing parameter adjustments made. RESULTS: There were 909 DBS tele-programming health service requests (from 196 patients) completed during the study period. The results showed: 1) the number of DBS telemedicine sessions requested and the number of patients examined increased during the COVID-19 outbreak in February and March 2020 when compared with the monthly numbers in 2019; 2) the most common reason for the patients' health service requests was poor symptom control; 3) the most common DBS tele-programming adjustment made was voltage change; 4) overall, most (89%) DBS tele-programming adjustment sessions were experienced by the patients as satisfactory; and 5) significant adverse events and unexpected treatment interruptions caused by connection failure or other hardware- or software-related problems did not occur. CONCLUSIONS: DBS telemedicine could have a unique role to play in maintaining the delivery of DBS treatment and medical care to outpatients with movement disorders during the COVID-19 pandemic.

Dynamic changes in rhythmic and arrhythmic neural signatures in the subthalamic nucleus induced by anaesthesia and tracheal intubation.

BACKGROUND: Subcortical structures, including the basal ganglia, have been proposed to be crucial for arousal, consciousness, and behavioural responsiveness. How the basal ganglia contribute to the loss and recovery of consciousness during anaesthesia has, however, not yet been well characterised. METHODS: Twelve patients with advanced Parkinson's disease, who were undergoing deep brain stimulation (DBS) electrode implantation in the subthalamic nucleus (STN), were included in this study. Local field potentials (LFPs) were recorded from the DBS electrodes and EEG was recorded from the scalp during induction of general anaesthesia (with propofol and sufentanil) and during tracheal intubation. Neural signatures of loss of consciousness and of the expected arousal during intubation were sought in the STN and EEG recordings. RESULTS: Propofol-sufentanil anaesthesia resulted in power increases in delta, theta, and alpha frequencies, and broadband power decreases in higher frequencies in both STN and frontal cortical areas. This was accompanied by increased STN-frontal cortical coherence only in the alpha frequency band (119 [68]%; P=0.0049). We observed temporal activity changes in STN after tracheal intubation, including power increases in high-beta (22-40 Hz) frequency (98 [123]%; P=0.0064) and changes in the power-law exponent in the power spectra at lower frequencies (2-80 Hz), which were not observed in the frontal cortex. During anaesthesia, the dynamic changes in the high-gamma power in STN LFPs correlated with the power-law exponent in the power spectra at lower frequencies (2-80 Hz). CONCLUSIONS: Apart from similar activity changes in both STN and cortex associated with anaesthesia-induced unresponsiveness, we observed specific neuronal activity changes in the STN in response to the anaesthesia and tracheal intubation. We also show that the power-law exponent in the power spectra in the STN was modulated by tracheal intubation in anaesthesia. Our results support the hypothesis that subcortical nuclei may play an important role in the loss and return of responsiveness.

Spinal Cord Stimulation with Surgical Lead Improves Pain and Gait in Parkinson's Disease after a Dislocation of Percutaneous Lead: A Case Report.

Spinal cord stimulation (SCS) is receiving increasing interests for treating pain and gait disorders in patients with Parkinson's disease (PD). In an SCS study, it is hard to apply a double-blind approach, especially at low frequencies, as the stimulation normally induces paresthesia which can be perceived by the patient. We herein demonstrate a case treated with SCS in which a blinding design was accomplished by an accidental dislocation of a stimulation lead. A 73-year-old man with PD was admitted to our hospital because of relapsed low back pain. This was due to the dislocation of a previously implanted SCS lead, which caused a decrease in its effectiveness in alleviating pain (from 81 to 43% measured by King's Parkinson's Disease Pain Scale) and improving gait (from 35 to 28% measured by the timed up and go test). A second SCS surgery using a paddle lead solved this problem, with improvements in pain and gait rebounded to 81 and 45%. In this case, the paresthesia induced by SCS (using either a paddle lead or percutaneous leads) was below the threshold of perception when the patient was sitting and standing, and a dislocation of one previously implanted percutaneous lead did not cause evident changes in his sensation of paresthesia. At last follow-up, the patient's quality of life had improved by 40% as measured by the 8-item Parkinson's Disease questionnaire (PDQ-8). This study could serve partly as a proof that low-frequency SCS is effective in improving pain as well as gait problems in PD patients, which was unlikely a result of a placebo effect.

Long non-coding RNA Linc00320 inhibits glioma cell proliferation through restraining Wnt/ß-catenin signaling.

Recent efforts have revealed that numerous oncogenic lncRNAs have been found play pivotal role in Glioma progression while there is little know about anti-oncogenic lncRNAs in Glioma. In current study, we found a HMGB1 regulated lncRNA, Linc00320, is significantly decreased in Glioma malignant tissues and its low expression predicts poor prognosis. Moreover, we found that the nucleus localized Linc00320 inhibits Glioma cell proliferation both in vitro and in vivo. In addition, we found that Linc00320 binds to ß-catenin and inhibits the activity of Wnt/ß-catenin signaling by disrupting ß-catenin binds to TCF4 in Glioma cells. Taken together, we firstly demonstrated the tumor suppressive lncRNA, Linc00320, is down-regulated in Glioma tissues and inhibits Glioma cell proliferation by restraining Wnt/ß-catenin signaling through segregating ß-catenin and TCF4 and revealed the novel HMGB1/Linc00320/ß-catenin axis in Glioma progression.

Lead fixation in deep brain stimulation: comparison of three lead anchoring devices in China.

BACKGROUND: The accuracy of deep brain stimulation (DBS) depends on precise electrode positioning, which has been pursued for ideal treatment outcomes. As a critical component of DBS, the fixation performance of lead anchoring devices has been widely studied. Possible reasons for lead shift were analyzed in the current study and we further provided effective solutions to reduce potential manual errors. METHODS: Seventy-nine patients who received DBS implantations at the Ruijin Hospital from April to November 2017 were retrospectively reviewed. Intraoperative lead shifts were measured by C-arm fluoroscopy. Lead adjustment counts were recorded and compared among three lead fixation devices: Stimloc™ (Medtronic, Minneapolis, MN, USA), TouchLoc (SceneRay, Suzhou, China), and the traditional lead anchoring device. RESULTS: Mean (± SD) distances of lead shifts were 0.29 ± 2.42 mm in Stimloc devices, 0.43 ± 0.55 mm in TouchLoc devices, and 1.52 ± 1.05 mm in traditional devices (p < 0.0001). Average numbers of adjustments in this series were 0.3 ± 0.5 in Stimloc devices, 0.3 ± 1.3 in TouchLoc devices, and 1.1 ± 1.0 in traditional devices (p = 0.0001). Pairwise comparisons among the three devices (TouchLoc vs. Stimloc: p = 0.273; TouchLoc vs. Traditional: p = 0.0001; Stimloc vs. traditional: p < 0.0001) suggested significant differences, which were mainly attributed to the traditional devices. CONCLUSIONS: Three lead anchoring devices have been compared for their performance in the accuracy of lead fixation, in which the newly designed lead fixation devices have presented its advantages to the traditional one. In addition to the application of the Stimloc and TouchLoc devices, verification by C-arm fluoroscopy should be performed to provide an intuitive view of the depth deviation of electrode position during DBS electrode implantation.

Spinal Cord Stimulation Combined with Anterior Cingulotomy to Manage Refractory Phantom Limb Pain.

BACKGROUND: Phantom limb pain (PLP) is an intractable and debilitating disease without satisfactory treatment options presently available. Central reorganization, peripheral changes, and psychiatric factors contribute to its development; thus, a neuropsychiatry-orientated combined therapy could be promising. OBJECTIVES: We used a combined strategy with the aims of demonstrating its therapeutic outcomes on PLP. METHODS: The patient initially received spinal cord stimulation (SCS) implantation and then anterior cingulotomy (ACING) 2 years later. We administered the Hamilton Depression Scale-24, Hamilton Anxiety Scale, Pain Rating Index, Numerical Pain Rating Scale, and the Short Form (36) Health Survey to assess its outcomes at 5 time points, namely the time before performing SCS implantation, 1 year and 2 years after SCS implantation, and 1 year and 2 years after SCS combined with ACING. RESULTS: Excellent pain relief and significant improvement in depression symptoms were observed in this patient with PLP who underwent SCS combined with ACING. CONCLUSIONS: This report suggests that SCS combined with ACING is efficacious for PLP. However, further studies are warranted.

The regulation of lipid metabolism by a hypothetical P-loop NTPase and its impact on fecundity of the brown planthopper.

BACKGROUND: Insect fecundity can be regulated by multiple genes in several important signaling pathways which form an extremely complicated regulatory network. However, there are still many genes that have significant impact on insect fecundity but their action mode are still unknown. METHODS: Quantitative real-time PCR (qRT-PCR), immunofluorescence and western blot were used to study the expression profile of Nl23867 in the brown planthopper, Nilaparvata lugens. RNA interference (RNAi), RNA-seq and isobaric tags for relative and absolute quantification (iTRAQ) were performed to investigate the action mode of Nl23867 in the regulation of fecundity. High performance liquid chromatography (HPLC) analysis was performed to detect the fatty acid contents. RESULTS: We show that knockdown of Nl23867, a gene encoding a hypothetical P-loop NTPase, significantly decreased fecundity of N. lugens. Underdeveloped ovaries, fewer eggs laid and reduction in vitellogenin (Vg) protein expression were observed after RNAi knockdown of Nl23867, and most of the affected genes and pathways are fatty acid metabolism-related. We further determined that Nl23867 directly impacts the palmitic acid biosynthesis by regulating the expression of palmitoyl-protein thioesterase (PPT), subsequently affecting the content of total lipids in N. lugens. CONCLUSIONS: Nl23867 regulates the fecundity of N. lugens by modulating the biosynthetic pathway of palmitic acid and affecting lipid metabolism during vitellogenesis and oocyte development. GENERAL SIGNIFICANCE: The presented study pioneers the exploration into how a function-unknown gene takes part in the regulation of fecundity in an insect, and will contribute to the construction of gene regulatory network for insect fecundity.

Over-expression of tetraspanin 8 in malignant glioma regulates tumor cell progression.

Tumor cell invasion and proliferation remain the overwhelming causes of death for malignant glioma patients. To establish effective therapeutic methods, new targets implied in these processes have to be identified. Tetraspanin 8 (Tspn8) forms complexes with a large variety of trans-membrane and/or cytosolic proteins to regulate several important cellular functions. In the current study, we found that Tspn8 was over-expressed in multiple clinical malignant glioma tissues, and its expression level correlated with the grade of tumors. Tspn8 expression in malignant glioma cells (U251MG and U87MG lines) is important for cell proliferation and migration. siRNA-mediated knockdown of Tspn8 markedly reduced in vitro proliferation and migration of U251MG and U87MG cells. Meanwhile, Tspn8 silencing also increased the sensitivity of temozolomide (TMZ), and significantly increased U251MG or U87MG cell death and apoptosis by TMZ were achieved with Tspn8 knockdown. We observed that Tspn8 formed a complex with activated focal adhesion kinase (FAK) in both human malignant glioma tissues and in above glioma cells. This complexation appeared required for FAK activation, since Tspn8 knockdown inhibited FAK activation in U251MG and U87MG cells. These results provide evidence that Tspn8 contributes to the pathogenesis of glioblastoma probably by promoting proliferation, migration and TMZ-resistance of glioma cells. Therefore, targeting Tspn8 may provide a potential therapeutic intervention for malignant glioma.

Tetraspanin 8-rictor-integrin α3 complex is required for glioma cell migration.

The malignant glioma remains one of the most aggressive human malignancies with extremely poor prognosis. Glioma cell invasion and migration are the main causes of death. In the current study, we studied the expression and the potential functions of tetraspanin 8 (Tspan8) in malignant gliomas. We found that Tspan8 expression level is high in both malignant glioma tissues and in several human glioma cell lines, where it formed a complex integrin α3 and rictor, the latter is a key component of mammalian target of rapamycin (mTOR) complex 2 (mTORC2). Disruption of this complex, through siRNA-mediated knockdown of anyone of these three proteins, inhibited U251MG glioma cell migration in vitro. We further showed that Tspan8-rictor association appeared required for mTORC2 activation. Knockdown of Tspan8 by the targeted siRNAs prevented mTOR-rictor (mTORC2) assembly as well as phosphorylation of AKT (Ser-473) and protein kinase C α (PKCα) in U251MG cells. Together, these results demonstrate that over-expressed Tspan8 in malignant glioma forms a complex with rictor and integrin α3 to mediate mTORC2 activation and glioma cell migration. Therefore, targeting Tspan8-rictor-integrin α3 complex may provide a potential therapeutic intervention for malignant glioma.