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1.
Front Public Health ; 12: 1383884, 2024.
Article in English | MEDLINE | ID: mdl-38903579

ABSTRACT

Objective: This study aims to explore the relationship between sleep patterns and depressive symptoms among adolescents, examining variations in depressive symptoms across different sleep qualities, durations, and habits. Method: A cross-sectional survey was conducted, gathering data from 8,775 Chinese adolescents on their demographics, lifestyle habits, sleep quality and duration, and depressive symptoms. The association between sleep parameters and depressive symptoms was analyzed using multivariate logistic regression. Findings: The findings reveal a significant correlation between sleep quality/duration and depressive symptoms. Specifically, adolescents with poor sleep quality had higher depressive scores (mean score = 14.62, standard deviation = 5.71), significantly exceeding those with better sleep quality (mean score = 11.54, standard deviation = 4.69). Adolescents with shorter sleep duration also showed significantly higher depressive scores than those with moderate sleep duration. Importantly, adolescents experiencing both poor sleep quality and shorter sleep duration were at a significantly increased risk of depressive symptoms (OR = 4.04, 95% CI: 3.53-4.62, P < 0.001). Further analysis indicated that older age and lower family economic status were independent predictors of a higher risk of adolescent depression (OR = 1.22, 95% CI: 1.08-1.38, P = 0.001), whereas factors such as gender, ethnicity, residence, being an only child, and parental education levels were not statistically significant. Conclusion: Among Chinese adolescents, poor sleep quality and shorter sleep duration are independent predictors of higher depressive symptom scores. Adolescents experiencing both of these conditions simultaneously have a significantly increased risk of depressive symptoms. Furthermore, older age and lower family economic status are also significantly related to an increased risk of depression in adolescents. These findings emphasize the importance of improving sleep quality and optimizing sleep duration for the prevention of adolescent depression. They also suggest the need for a comprehensive approach that addresses the multifaceted factors influencing adolescent mental health, including sleep patterns and socioeconomic disparities.


Subject(s)
Depression , Sleep Quality , Students , Humans , Male , Female , Adolescent , Cross-Sectional Studies , Depression/epidemiology , China/epidemiology , Students/statistics & numerical data , Students/psychology , Surveys and Questionnaires , Sleep/physiology , Time Factors , Child , Risk Factors , Sleep Duration , East Asian People
2.
J Am Chem Soc ; 146(1): 1174-1184, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38153040

ABSTRACT

Controlling multimetallic ensembles at the atomic level is significantly challenging, particularly for high-entropy alloys with more than five elements. Herein, we report an innovative ultrasmall (∼2 nm) PtFeCoNiCuZn high-entropy intermetallic (PFCNCZ-HEI) with a well-ordered structure synthesized by using the space-confined strategy. By exploiting these combined metals, the PFCNCZ-HEI nanoparticles achieve an ultrahigh mass activity of 2.403 A mgPt-1 at 0.90 V vs reversible hydrogen electrode for the oxygen reduction reaction, which is up to 19-fold higher than that of state-of-the-art commercial Pt/C. A proton exchange membrane fuel cell assembled with PFCNCZ-HEI as the cathode (0.03 mgPt cm-2) exhibits a power density of 1.4 W cm-2 and a high mass-normalized rated power of 45 W mgPt-1. Furthermore, theoretical calculations reveal that the outer electrons of the non-noble-metal atoms on the surface of the PFCNCZ-HEI nanoparticle are modulated to show characteristics of multiple active centers. This work offers a promising catalyst design direction for developing highly ordered HEI nanoparticles for electrocatalysis.

3.
Anal Methods ; 15(22): 2736-2744, 2023 Jun 08.
Article in English | MEDLINE | ID: mdl-37232208

ABSTRACT

Bisphenol F (BPF) and its derivatives have a wide range of applications in plastic, coating and other important chemical industries. However, the parallel-consecutive reaction feature makes the synthesis of BPF very complicated and difficult to control. Precise control of the process is the key to a safer and more efficient industrial production. Herein, an in situ monitoring technology of BPF synthesis based on spectroscopy (attenuated total reflection infrared, Raman) was established for the first time. Using quantitative univariate models, the mechanism and reaction kinetics were studied in depth. Moreover, a better process route with a relatively low phenol/formaldehyde ratio was optimized with the in situ monitoring technology established, which could be used for much more sustainable scaled-up production. The present work could lead to application of in situ spectroscopic technologies in chemical and pharmaceutical industries.


Subject(s)
Phenol , Phenols , Kinetics , Spectrum Analysis
4.
Synth Syst Biotechnol ; 7(4): 1133-1141, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36092272

ABSTRACT

Astaxanthin is a high value carotenoid with a broad range of commercial applications due to its superior antioxidant properties. In this study, ß-carotene-producing Yarrowia lipolytica XK17 constructed in the lab was employed for astaxanthin biosynthesis. The catalytic effects of ß-carotene ketolase CrtW and ß-carotene hydroxylase CrtZ from various species were investigated. The PspCrtW from Paracoccus sp. and HpCrtZ# from Haematococcus pluvialis were confirmed to be the best combination in converting ß-carotene. Several key bottlenecks in biomass and astaxanthin biosynthesis were effectively eliminated by optimizing the expression of the above enzymes and restoring uracil/leucine biosynthesis. In addition, the effects of astaxanthin biosynthesis on cell metabolism were investigated by integrated analysis of pathway modification and transcriptome information. After further optimization, strain DN30 was able to synthesize up to 730.3 mg/L astaxanthin in laboratory 5-L fermenter. This study provides a good metabolic strategy and a sustainable development platform for high-value carotenoid production.

5.
Sensors (Basel) ; 22(4)2022 Feb 16.
Article in English | MEDLINE | ID: mdl-35214425

ABSTRACT

Unmanned aircraft systems are expected to provide both increasingly varied functionalities and outstanding application performances, utilizing the available resources. In this paper, we explore the recent advances and challenges at the intersection of real-time computing and control and show how rethinking sampling strategies can improve performance and resource utilization. We showcase a novel design framework, cyber-physical co-regulation, which can efficiently link together computational and physical characteristics of the system, increasing robust performance and avoiding pitfalls of event-triggered sampling strategies. A comparison experiment of different sampling and control strategies was conducted and analyzed. We demonstrate that co-regulation has resource savings similar to event-triggered sampling, but maintains the robustness of traditional fixed-periodic sampling forming a compelling alternative to traditional vehicle control design.

6.
Toxins (Basel) ; 12(11)2020 11 23.
Article in English | MEDLINE | ID: mdl-33238397

ABSTRACT

Since 1970s, aplysiatoxins (ATXs), a class of biologically active dermatoxins, were identified from the marine mollusk Stylocheilus longicauda, whilst further research indicated that ATXs were originally metabolized by cyanobacteria. So far, there have been 45 aplysiatoxin derivatives discovered from marine cyanobacteria with various geographies. Recently, we isolated two neo-debromoaplysiatoxins, neo-debromoaplysiatoxin G (1) and neo-debromoaplysiatoxin H (2) from the cyanobacterium Lyngbya sp. collected from the South China Sea. The freeze-dried cyanobacterium was extracted with liquid-liquid extraction of organic solvents, and then was subjected to multiple chromatographies to yield neo-debromoaplysiatoxin G (1) (3.6 mg) and neo-debromoaplysiatoxin H (2) (4.3 mg). They were elucidated with spectroscopic methods. Moreover, the brine shrimp toxicity of the aplysiatoxin derivatives representing differential structural classifications indicated that the debromoaplysiatoxin was the most toxic compound (half inhibitory concentration (IC50) value = 0.34 ± 0.036 µM). While neo-aplysiatoxins (neo-ATXs) did not exhibit apparent brine shrimp toxicity, but showed potent blocking action against potassium channel Kv1.5, likewise, compounds 1 and 2 with IC50 values of 1.79 ± 0.22 µM and 1.46 ± 0.14 µM, respectively. Therefore, much of the current knowledge suggests the ATXs with different structure modifications may modulate multiple cellular signaling processes in animal systems leading to the harmful effects on public health.


Subject(s)
Lyngbya Toxins/chemistry , Lyngbya Toxins/toxicity , Lyngbya , Potassium Channel Blockers/chemistry , Potassium Channel Blockers/toxicity , Animals , Artemia/drug effects , CHO Cells , Cricetulus , Kv1.5 Potassium Channel/antagonists & inhibitors , Kv1.5 Potassium Channel/genetics , Kv1.5 Potassium Channel/physiology
7.
Biotechnol Lett ; 42(6): 945-956, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32090297

ABSTRACT

OBJECTIVE: Carotenoids, as potent antioxidant compounds, have gained extensive attention, especially in human health. In this study, the combination of CRISPR/Cas9 integration strategy and fermenter cultivation was utilized to obtain efficient ß-carotene-producing Yarrowia lipolytica cell factories for potential industrial application. RESULTS: The introduction of the genes of Mucor circinelloides, encoding phytoene dehydrogenase (carB) and bifunctional phytoene synthase/lycopene cyclase (carRP), contributed to the heterologous production of ß-carotene in Y. lipolytica XK2. Furthermore, ß-carotene production was efficiently enhanced by increasing the copy numbers of the carB and carRP genes and overexpressing of GGS1, ERG13, and HMG, the genes related to the mevalonate (MVA) pathway. Thus, the optimized strain overexpressed a total of eight genes, including three copies of carRP, two copies of carB, and single copies of GGS1, HMG, and ERG13. As a consequence, strain Y. lipolytica XK19 accumulated approximately 408 mg/L ß-carotene in shake flask cultures, a twenty-four-fold increase compared to the parental strain Y. lipolytica XK2. CONCLUSIONS: 4.5 g/L ß-carotene was obtained in a 5-L fermenter through a combination of genetic engineering and culture optimization, suggesting a great capacity and flexibility of Y. lipolytica in the production of carotenoids.


Subject(s)
Metabolic Engineering/methods , Yarrowia/genetics , beta Carotene/metabolism , Bioreactors , CRISPR-Cas Systems/genetics , Fermentation , Glucose/metabolism , Yarrowia/metabolism , beta Carotene/analysis
8.
J Biotechnol ; 289: 46-54, 2019 Jan 10.
Article in English | MEDLINE | ID: mdl-30448359

ABSTRACT

Lycopene has been broadly studied in recent decades due to its health benefits including cancer prevention, anti-atherogenic and anti-obesity effects, and modulation of the immune system. To obtain efficient synthesis of lycopene, extensive researches have been conducted in various microbial cells, including Yarrowia lipolytica, to heterologously produce lycopene using various genetic and metabolic engineering methods. In this study, the effects of copy numbers of lycopene synthesis genes, a variety of key central metabolic genes (especially AMP deaminase-encoding gene AMPD), and 5-L fermenter cultivation on lycopene production in Y. lipolytica were investigated and the engineered strains with significantly enhanced lycopene content (46-60 mg/g DCW) were achieved. It is therefore possible to make use of the obtained strains to meet the industrial demand of lycopene production on the basis of further genetic and process optimization.


Subject(s)
AMP Deaminase/metabolism , Fungal Proteins/metabolism , Genes, Fungal , Lycopene/metabolism , Yarrowia/genetics , Yarrowia/metabolism
9.
Metabolites ; 5(4): 794-813, 2015 Dec 21.
Article in English | MEDLINE | ID: mdl-26703753

ABSTRACT

Genome-scale metabolic models embody a significant advantage of systems biology since their applications as metabolic flux simulation models enable predictions for the production of industrially-interesting metabolites. The biotechnological production of lycopene from Yarrowia lipolytica is an emerging scope that has not been fully scrutinized, especially for what concerns cultivation conditions of newly generated engineered strains. In this study, by combining flux balance analysis (FBA) and Plackett-Burman design, we screened chemicals for lycopene production from a metabolically engineered strain of Y. lipolytica. Lycopene concentrations of 126 and 242 mg/L were achieved correspondingly from the FBA-independent and the FBA-assisted designed media in fed-batch cultivation mode. Transcriptional studies revealed upregulations of heterologous genes in media designed according to FBA, thus implying the efficiency of model predictions. Our study will potentially support upgraded lycopene and other terpenoids production from existing or prospect bioengineered strains of Y. lipolytica and/or closely related yeast species.

10.
PLoS One ; 10(6): e0128394, 2015.
Article in English | MEDLINE | ID: mdl-26030143

ABSTRACT

INTRODUCTION: In China, the severity of medical disputes has greatly increased during the past two decades, which has caused various adverse outcomes for health professionals. Previous research on violence in healthcare settings has primarily examined the occurrence of patient-initiated violence and its effects on physicians, but few studies have focused on the impact of the extent of physicians' exposure to violence. This study examined the different frequency levels of specific types of violence and their relationships to physicians' psychological wellbeing, including emotional exhaustion (EE), job satisfaction (JS), and intention to leave (IL). METHODS: Using a stratified random sampling method, the participants were drawn from 123 public hospitals in Shanghai, Hubei Province, and Gansu Province in China, and 1,656 completed questionnaires were collected. Chi-square test, analysis of variance, and mixed linear model were employed in the analysis. RESULTS: The results showed that the rate of exposure to verbal abuse (VA) was the highest (92.75%), followed by threats of assault (TA, 88.10%) and physical assaults (PA, 81.04%). Physicians' reported high-frequency exposure to VA, TA, and PA was 35.14%, 27.72%, and 19.32%, respectively. The results indicated that exposure to violence significantly affected EE, JS, and IL, and the intensity of the harm of high-frequency exposure was several times stronger than that of low-frequency exposure. Interestingly, we found that VA produced a greater adverse impact on physicians' EE and satisfaction with work (JS-1) than did TA or PA. This finding may be attributed to the fact that physicians are more likely to be exposed to a high frequency of VA, and the effect of high-frequency exposure is much stronger. CONCLUSION: The results indicated that decreasing violent incidents and creating a safer work environment for physicians should be a top priority for both government and society.


Subject(s)
Patients/psychology , Physicians/psychology , Violence , China , Cross-Sectional Studies , Female , Humans , Male
11.
Chin Med J (Engl) ; 125(14): 2505-10, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22882930

ABSTRACT

BACKGROUND: Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) has been successfully used to treat degenerative diseases of the lumbar spine. There are few reports comparing the complications and clinical outcomes in older patients who have undergone one- or two-level MIS-TLIF with those of younger patients. The aim of this study was to investigate the clinical outcomes of MIS-TLIF in the treatment of degenerative disc disease of lumbar spine of the patients older than 65 years, with an emphasis on perioperative complications compared to the younger patients. METHODS: One hundred and fifty-one consecutive cases of one- or two-level degenerative disc disease of lumbar spine treated with MIS-TLIF were reviewed for the radiological and clinical outcomes. They were divided into elderly group (age ≥ 65 years old) and younger group (age < 65 years old), and were followed for at least 6 months. Radiographs were obtained before and after surgery, 3 months postoperatively, and at the final follow-up to determine the presence of fusion, hardware-related problems. The clinical outcomes were evaluated using the Oswestry Disability Index (ODI) before and after surgery, and at the final follow-up. The visual analogue scale (VAS) score of back and leg pain were evaluated as well. The intra-operative data and peri-operative complications were recorded. RESULTS: The mean age of these patients at operation was (57.7 ± 14.2) years (range 26 - 82 years). Of 151 patients, 62 were 65 years or older. The elderly patients had more comorbidities and more porportion of lumbar canal stenosis. The overall fusion rate was 88.4% at the final follow-up, with no significant difference between younger and elderly patients. The ODI, the VAS of back pain and radicular pain of both young and elderly group were significantly improved after surgery and at the final follow-up, without significant difference between two groups. There were 16 complications with an incidence of 10.6%, including 7 major complications and 9 minor complications. There was no significant difference of the incidence of complications between two groups. The incidence of dura tear was significantly related to bilateral deompression. CONCLUSIONS: The clinical and radiological outcomes of MIS-TLIF in the treatment of one- or two-level degenerative disc diseases of lumbar spine in the elderly patients were satisfactory. Though there are more pre-operative comorbidities, with proper patient selection, the elderly patients are not at increased risk of perioperative complications compared to younger patients. Screw malposition and dura tear, which are the most frequent complications, were more related to the surgical technique and should be avoided.


Subject(s)
Intervertebral Disc Degeneration/surgery , Lumbar Vertebrae/surgery , Spinal Fusion/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Intervertebral Disc Degeneration/diagnostic imaging , Lumbar Vertebrae/diagnostic imaging , Male , Middle Aged , Radiography , Spinal Fusion/adverse effects , Treatment Outcome
12.
Chin Med J (Engl) ; 121(15): 1364-8, 2008 Aug 05.
Article in English | MEDLINE | ID: mdl-18959110

ABSTRACT

BACKGROUND: A simple, safe and effective therapeutic strategy for traumatic instability of the subaxial cervical spine, as well as its prognostic assessment, is still controversial. METHODS: The therapeutic options for 83 patients of traumatic instability of the subaxial cervical spine, whose average age was 35 years, were determined, according to the Allen-Ferguson classification, general health and concomitant traumatic conditions, neurological function, position of compression materials, concomitant traumatic disc herniation/damage, concomitant locked-facet dislocation, the involved numbers and position, and the patients' economic conditions. An anterior, posterior or combination approach was used to decompress and reconstruct the cervical spine. No operations with an anterior-posterior-anterior approach were performed. RESULTS: The average follow-up was three years and nine months. Distraction-flexion and compression-flexion were the most frequent injury subtypes. There were 46, 28 and 9 cases of anterior, posterior and combination operations, respectively. The average score of the Japanese Orthopaedics Association, visual analog scale and American Spinal Cord Injury Association (ASIA) motor index improved from 11.2, 7.8 and 53.5, respectively, before operation, to 15.3, 2.6 and 67.8, respectively, at final follow-up. For incomplete spinal cord injury (SCI), the average ASIA neurological function scale was improved by 1-2 levels. Patients with complete SCI had no neurological recovery, but recovery of nerve root function occurred to different extents. After surgery, radiological parameters improved to different extents. Fusion was achieved in all patients and 12 developed complications. CONCLUSIONS: The best surgical strategy should be determined by the type of subaxial cervical injury, patients' general health, local pathological anatomy and neurological function.


Subject(s)
Cervical Vertebrae/injuries , Cervical Vertebrae/surgery , Joint Instability/surgery , Spinal Diseases/surgery , Adolescent , Adult , Aged , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Retrospective Studies
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