14 research outputs found
Co-translational protein targeting facilitates centrosomal recruitment of PCNT during centrosome maturation in vertebrates.
As microtubule-organizing centers of animal cells, centrosomes guide the formation of the bipolar spindle that segregates chromosomes during mitosis. At mitosis onset, centrosomes maximize microtubule-organizing activity by rapidly expanding the pericentriolar material (PCM). This process is in part driven by the large PCM protein pericentrin (PCNT), as its level increases at the PCM and helps recruit additional PCM components. However, the mechanism underlying the timely centrosomal enrichment of PCNT remains unclear. Here, we show that PCNT is delivered co-translationally to centrosomes during early mitosis by cytoplasmic dynein, as evidenced by centrosomal enrichment of PCNT mRNA, its translation near centrosomes, and requirement of intact polysomes for PCNT mRNA localization. Additionally, the microtubule minus-end regulator, ASPM, is also targeted co-translationally to mitotic spindle poles. Together, these findings suggest that co-translational targeting of cytoplasmic proteins to specific subcellular destinations may be a generalized protein targeting mechanism
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Understanding the Functional Contribution of Pericentrin to Centrosome Assembly in Vertebrates
The centrosome functions as the main microtubule-organizing center in metazoan cells and orchestrates diverse cellular processes critical for development, including cell division, polarization, and migration. Centrosome dysfunction is associated with cancer and microcephaly in human, warranting a mechanistic understanding of its assembly in vertebrates. The centrosome is a membraneless organelle that consists of a pair of centrioles embedded in a proteinaceous network named pericentriolar material (PCM). The PCM is a complex ensemble of proteins enriched with coiled-coil domains (CCs) and low-complexity regions (LCRs). At the onset of mitosis, centrosomes expand the PCM to maximize their microtubule nucleation capacity. This process, termed centrosome maturation, ensures proper mitotic spindle assembly and chromosome segregation in mitosis. However, as the centrosome expands, how PCM proteins are recruited and held together without membrane enclosure remains elusive. This dissertation work primarily focuses on understanding the functional contribution of pericentrin (PCNT), a conserved PCM component, to centrosome assembly in vertebrates. I found that endogenously expressed PCNT condenses into dynamic aliphatic alcohol-sensitive granules around centrosomes during late G2/early mitosis in human cells. These data suggest that full-length PCNT may undergo liquid-liquid phase separation (LLPS) in physiologically relevant conditions during centrosome maturation. Furthermore, the N-terminal and middle segments of PCNT, enriched with conserved CCs and LCRs, undergo concentration-dependent condensation. Formation of PCNT “condensates” exhibits characteristics of LLPS, including a sharp phase transition at a concentration threshold, as well as coalescence, deformability, and rapid fluorescence recovery after photobleaching. Moreover, these PCNT condensates selectively recruit endogenous PCM components and nucleate microtubules in cells. We propose that CCs and LCRs, two prevalent sequence features in the centrosomal proteome, are preserved under evolutionary pressure in part to mediate LLPS, a process that bestows upon the centrosome distinct properties critical for its assembly and functions. Another part of the dissertation centers on developing computational methods for image analysis to study centrosome assembly in a quantitative manner. To accurately detect and quantify centrosome-localized mRNAs and proteins at single cell resolution, I developed a streamlined workflow for performing, acquiring, and analyzing sequential immunofluorescence and single-molecule RNA fluorescence in situ hybridization data via 3D reconstruction in Imaris, followed by quantifications using MATLAB and R. Moreover, to automatically track the dynamics and spatiotemporal distribution of condensates relative to centrosomes, I developed TRACES (Tracking of Active Cellular Structures), a customizable and open-source pipeline capable of detecting, tracking, and quantifying fluorescently labeled cellular structures in up to three spectral channels simultaneously at single-cell resolution. Overall, my studies provide a molecular and biophysical framework, as well as quantitative image analysis methods, for dissecting mechanisms underlying centrosome assembly in vertebrates
“An examination of Mozartian Sources in Stravinsky’s The Rake’s Progress.”
Individual presentations of research in music theory or music history
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Three-dimensional Reconstruction and Quantification of Proteins and mRNAs at the Single-cell Level in Cultured Cells.
Gene expression is often regulated by the abundance, localization, and translation of mRNAs in both space and time. Being able to visualize mRNAs and protein products in single cells is critical to understand this regulatory process. The development of single-molecule RNA fluorescence in situ hybridization (smFISH) allows the detection of individual RNA molecules at the single-molecule and single-cell levels. When combined with immunofluorescence (IF), both mRNAs and proteins in individual cells can be analyzed simultaneously. However, a precise and streamlined quantification method for the smFISH and IF combined dataset is scarce, as existing workflows mostly focus on quantifying the smFISH data alone. Here we detail a method for performing sequential IF and smFISH in cultured cells (as described in Sepulveda et al., 2018 ) and the subsequent statistical analysis of the smFISH and IF data via three-dimensional (3D) reconstruction in a semi-automatic image processing workflow. Although our method is based on analyzing centrosomally enriched mRNAs and proteins, the workflow can be readily adapted for performing and analyzing smFISH and IF data in other biological contexts
Medical resource utilization and the associated costs of asthma in China: a 1-year retrospective study
Abstract Background Despite evidence that severe and poorly controlled asthma are associated with more clinical unmet needs and intensive utilization of healthcare resources, limited data is available on severe asthma expenditure in China. The study aimed to assess Medical Resource Utilization (MRU) costs of asthma and explore the cost drivers in order to better understand the economic burden of the Chinese population suffered from asthma. Methods A retrospective analysis was conducted using Chinese sampled national claim database. Patients aged 6 years and above with primary diagnosis of asthma and asthma-related medical visit/hospitalization during 2015 were included. Medication was used as a proxy per the GINA and China guideline to identify asthma severity (i.e. mild, moderate, and severe). multiple linear regression model was conducted to identify MRU costs drivers. Results 7,254 patients diagnosed with asthma were included: 4,529 (62.4%), 2,200 (30.3%), and 525 (7.2%) had mild, moderate, and severe asthma, respectively. On average, each severe patient spent 6,782 Chinese Yuan (CNY) on asthma treatment and had 57.0% hospitalization rate during the year, 3.9- and 4.4-fold of the average of overall population (P < 0.001 for both). The proportion of patients experiencing exacerbation significantly higher in the severe asthma population (66.5%; P < 0.001) compared to mild (30.0%) and moderate (16.8%) groups. In subgroup with 1,660 samples had annual consecutive data, severe patients had annual cost of CNY 8,314 and 52.2% hospitalization rate. 13% of severe patients who had frequent severe exacerbation (≥ 2 events) experienced the highest annual average cost CNY 23,037, P < 0.001) whereas children aged from 6 to 14 with a lower annual cost of CNY 1,094.2, 1,660.2 and 3,020.2 for mild, moderate, and severe patients respectively. The multiple model identified degree of severity, control status, complications, age, and live region as independent drivers of MRU costs. Conclusions Chinese asthma patients bear heavy economic burden. Severe asthma associated with higher MRU (mainly from hospitalization) and costs compared with mild to moderate asthma in China. More efforts should be devoted to the control of the disease severity and complication as the main drivers of asthma cost
A Silk Protein-Based Eutectogel as a Freeze-Resistant and Flexible Electrolyte for Zn-Ion Hybrid Supercapacitors
A eutectogel (ETG) based on immobilizing a zinc salt
deep eutectic
solvent (DES) in a silk protein backbone is prepared by a coagulating
bath method as a solid electrolyte for Zn-ion hybrid supercapacitors
(ZHSCs). The Zn salt DES is composed by ethylene glycol (EG), urea,
choline chloride (ChCl), and zinc chloride (ZnCl2) with
a molar ratio of 6:10:3:3. A strong bonding of the DES liquid to the
silk protein backbone is formed between protein macromolecules and
the DES due to plenty of hydrogen bonds in both materials. The as-prepared
ETG membrane is dense and has no obvious void defects, which possesses
a fracture strength of 7.58 MPa and environmental stability. As a
solid electrolyte, the ETG membrane exhibits a higher Zn2+ transference number of about 0.60 and a high ionic conductivity
(12.31 mS cm–1 at room temperature and 3.63 mS cm–1 at −20 °C). A ZHSC (Zn∥ETG∥C)
with the silk protein-based ETG electrolyte is assembled by Zn and
active carbon as the anode and the cathode, respectively, which delivers
a specific capacitance of 342.8 F g–1 at a current
density of 0.2 A g–1 and maintains excellent cycling
stability with 80% capacitance retention after 20,000 cycles at a
high current rate (5 A g–1) at room temperature.
Moreover, the Zn∥ETG∥C device can safely work under
a lower temperature of about −18 °C and damaging situations,
such as folding states and even cutting tests. The interface evolutions
between the Zn anode and the ETG electrolyte are explored, and it
was found that a ZnCO3/Zn(CH2OCO2)2 solid electrolyte interphase is in situ formed on the
Zn anode, which can inhibit the growth of Zn dendrites. This work
provides a new way to fabricate advanced electrolytes for applications
in Zn-ion hybrid supercapacitors
Comparative short-term efficacy and acceptability of a combination of pharmacotherapy and psychotherapy for depressive disorder in children and adolescents:a systematic review and meta-analysis
BACKGROUND: Although the clinical efficacy and safety of combination of pharmacotherapy and psychotherapy in the treatment of depressive disorders in children and adolescents have been studied, the results remain controversial. This meta-analysis aimed to study the short-term efficacy and acceptability of combined therapy for children and adolescents with depressive disorders. METHODS: We conducted a systematic search in multiple databases for randomised controlled trials (RCTs), up to 31 December 2020, that assessed the combination of pharmacotherapy and psychotherapy against other active treatment options (pharmacotherapy, psychotherapy and placebo combined psychotherapy) in children and adolescents ( ≤ 18 years old) with depressive disorder. This study was registered with PROSPERO (CRD42020196701). RESULTS: A total of 14 RCTs involving 1,325 patients were included. For the primary and secondary outcomes, there were no statistically significant differences between the compared interventions in terms of remission (odds ratios [OR] = 1.37; 95% confidence interval [CI]: 0.93 to 2.04), acceptability (OR = 0.99; 95% CI: 0.72 to 1.38), efficacy (standardised mean differences = -0.07; 95% CI: -0.32 to 0.19), and suicidality (OR = 1.17; 95% CI: 0.67 to 2.06). Limited evidence showed that the combination of fluoxetine (OR = 1.90, 95% CI: 1.10 to 3.29) or non-selective serotonin reuptake inhibitors (non-SSRI) (OR = 2.46, 95% CI: 1.06 to 5.72) with cognitive-behavioural therapy (CBT) was superior to other active treatment options. Most included trials were rated as ‘some concerns’ in terms of risk of bias assessment. CONCLUSION: There is no evidence from the limited available data that all combined therapies are superior to other active treatment options for the acute treatment of depressive disorder in children and adolescents. However, it showed that fluoxetine or non-SSRI pharmacotherapies combined with CBT might be superior to other therapies in short-term. Mixed characteristics (e.g. age) and small sample size of non-SSRI combined therapy may influence the generalisability of the results. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12888-022-03760-2
Comparative efficacy and acceptability of psychotherapies for post-traumatic stress disorder in children and adolescents: a systematic review and network meta-analysis
Background: Available evidence on the comparative efficacy and acceptability of psychotherapies for post-traumatic stress disorder (PTSD) in children and adolescents remains uncertain.
Objective: We aimed to compare and rank the different types and formats of psychotherapies for PTSD in children and adolescents.
Methods: We searched eight databases and other international registers up to 31 December 2020. The pairwise meta-analyses and frequentist network meta-analyses estimated pooled standardised mean differences (SMDs) and ORs with random-effects model. Efficacy at post-treatment and follow-up, acceptability, depressive and anxiety symptoms were measured.
Findings: We included 56 randomised controlled trials with 5327 patients comparing 14 different types of psychotherapies and 3 control conditions. For efficacy, cognitive processing therapy (CPT), behavioural therapy (BT), individual trauma-focused cognitive–behavioural therapy (TF-CBT), eye movement desensitisation and reprocessing, and group TF-CBT were significantly superior to all control conditions at post-treatment and follow-up (SMDs between −2.42 and −0.25). Moreover, CPT, BT and individual TF-CBT were more effective than supportive therapy (SMDs between −1.92 and −0.49). Results for depressive and anxiety symptoms were similar to the findings for the primary outcome. Most of the results were rated as ‘moderate’ to ‘very low’ in terms of confidence of evidence.
Conclusions: CPT, BT and individual TF-CBT appear to be the best choices of psychotherapy for PTSD in young patients. Other types and different ways of delivering psychological treatment can be alternative options. Clinicians should consider the importance of each outcome and the patients’ preferences in real clinical practice
Comparative short-term efficacy and acceptability of a combination of pharmacotherapy and psychotherapy for depressive disorder in children and adolescents: a systematic review and meta-analysis
Background: Although the clinical efficacy and safety of combination of pharmacotherapy and psychotherapy in the treatment of depressive disorders in children and adolescents have been studied, the results remain controversial. This meta-analysis aimed to study the short-term efficacy and acceptability of combined therapy for children and adolescents with depressive disorders. Methods: We conducted a systematic search in multiple databases for randomised controlled trials (RCTs), up to 31 December 2020, that assessed the combination of pharmacotherapy and psychotherapy against other active treatment options (pharmacotherapy, psychotherapy and placebo combined psychotherapy) in children and adolescents (≤ 18 years old) with depressive disorder. This study was registered with PROSPERO (CRD42020196701). Results: A total of 14 RCTs involving 1,325 patients were included. For the primary and secondary outcomes, there were no statistically significant differences between the compared interventions in terms of remission (odds ratios [OR] = 1.37; 95% confidence interval [CI]: 0.93 to 2.04), acceptability (OR = 0.99; 95% CI: 0.72 to 1.38), efficacy (standardised mean differences = -0.07; 95% CI: -0.32 to 0.19), and suicidality (OR = 1.17; 95% CI: 0.67 to 2.06). Limited evidence showed that the combination of fluoxetine (OR = 1.90, 95% CI: 1.10 to 3.29) or non-selective serotonin reuptake inhibitors (non-SSRI) (OR = 2.46, 95% CI: 1.06 to 5.72) with cognitive-behavioural therapy (CBT) was superior to other active treatment options. Most included trials were rated as ‘some concerns’ in terms of risk of bias assessment. Conclusion: There is no evidence from the limited available data that all combined therapies are superior to other active treatment options for the acute treatment of depressive disorder in children and adolescents. However, it showed that fluoxetine or non-SSRI pharmacotherapies combined with CBT might be superior to other therapies in short-term. Mixed characteristics (e.g. age) and small sample size of non-SSRI combined therapy may influence the generalisability of the results
Comparative efficacy and acceptability of psychotherapies for post-traumatic stress disorder in children and adolescents: a systematic review and network meta-analysis.
BACKGROUND
Available evidence on the comparative efficacy and acceptability of psychotherapies for post-traumatic stress disorder (PTSD) in children and adolescents remains uncertain.
OBJECTIVE
We aimed to compare and rank the different types and formats of psychotherapies for PTSD in children and adolescents.
METHODS
We searched eight databases and other international registers up to 31 December 2020. The pairwise meta-analyses and frequentist network meta-analyses estimated pooled standardised mean differences (SMDs) and ORs with random-effects model. Efficacy at post-treatment and follow-up, acceptability, depressive and anxiety symptoms were measured.
FINDINGS
We included 56 randomised controlled trials with 5327 patients comparing 14 different types of psychotherapies and 3 control conditions. For efficacy, cognitive processing therapy (CPT), behavioural therapy (BT), individual trauma-focused cognitive-behavioural therapy (TF-CBT), eye movement desensitisation and reprocessing, and group TF-CBT were significantly superior to all control conditions at post-treatment and follow-up (SMDs between -2.42 and -0.25). Moreover, CPT, BT and individual TF-CBT were more effective than supportive therapy (SMDs between -1.92 and -0.49). Results for depressive and anxiety symptoms were similar to the findings for the primary outcome. Most of the results were rated as 'moderate' to 'very low' in terms of confidence of evidence.
CONCLUSIONS
CPT, BT and individual TF-CBT appear to be the best choices of psychotherapy for PTSD in young patients. Other types and different ways of delivering psychological treatment can be alternative options. Clinicians should consider the importance of each outcome and the patients' preferences in real clinical practice