The impact of isolation on comorbidity of PTSD symptoms and depression: evidence from PTRP-5-6 in China.

BACKGROUND: The Omicron pandemic struck Shanghai, China, resulting in impairments of both physical and psychological health on those patients who were confirmed and transferred to the Fangcang shelters. The way of isolation led to high risk of posttraumatic stress symptoms (PTSS) and depressive symptoms among the patients in Fangcang shelters. We aim to estimate the prevalence and comorbidity of PTSS and depressive symptoms in patients from China's Fangcang shelters during the epidemic. METHODS: Demographic information questionnaire, the posttraumatic stress disorder checklist for DSM-5 (PCL-5), and Patient Health Questionnaire (PHQ-9) were used in the study. The data were collected online via mobile phones during 10th April to 20th April, 2022, as part of our Psychological Trauma Recover Project-5-6 (PTRP-5-6), a longitudinal study focusing on individuals who have experienced trauma. RESULTS: A total of 336 subjects were included in the analysis. The results revealed (1) the prevalence of depressive symptoms, and PTSS were 30.1% (cut-off = 10) and 6% (cut-off = 33); (2) Multiple logistic regression showed that female (OR = 3.04, p < 0.05), suffering from dyspnea (OR = 5.83, p < 0.05) or gastrointestinal symptoms (OR = 6.38, p < 0.05) were risk factors for PTSS; higher education level (OR = 3.27, p < 0.05) and suffering from dizziness or headache (OR = 2.46, p < 0.05) were risk factors for depressive symptoms; (3)Respectively, 85% of the patients who reported PTSS also experienced depressive symptoms, 16.8% of the patients who reported depressive symptoms presented PTSS. CONCLUSION: In the context of COVID-19, the comorbidity rate of PTSS and depressive symptoms among patients in Fangcang shelters increased with the severity of depressive symptoms.

Evaluating and Enhancing Large Language Models' Performance in Domain-specific Medicine: Explainable LLM with DocOA.

BACKGROUND: Evaluating and Enhancing Large Language Models' Performance in Domain-specific Medicine: Explainable LLM with DocOA. OBJECTIVE: This study focused on evaluating and enhancing the clinical capabilities and explainability of LLMs in specific domains, using osteoarthritis (OA) management as a case study. METHODS: A domain specific benchmark framework was developed, which evaluate LLMs across a spectrum from domain-specific knowledge to clinical applications in real-world clinical scenarios. DocOA, a specialized LLM designed for OA management integrating retrieval-augmented generation (RAG) and instructional prompts, was developed. It can identify the clinical evidence upon which its answers are based through RAG, thereby demonstrating the explainability of those answers. The study compared the performance of GPT-3.5, GPT-4, and a specialized assistant, DocOA, using objective and human evaluations. RESULTS: Results showed that general LLMs like GPT-3.5 and GPT-4 were less effective in the specialized domain of OA management, particularly in providing personalized treatment recommendations. However, DocOA showed significant improvements. CONCLUSIONS: This study introduces a novel benchmark framework which assesses the domain-specific abilities of LLMs in multiple aspects, highlights the limitations of generalized LLMs in clinical contexts, and demonstrates the potential of tailored approaches for developing domain-specific medical LLMs.

Flexible Substrate-Compatible and Efficiency-Improved Quantum-Dot Light-Emitting Diodes with Reduced Annealing Temperature of NiOx Hole-Injecting Layer.

The growing demand for wearable and attachable displays has sparked significant interest in flexible quantum-dot light-emitting diodes (QLEDs). However, the challenges of fabricating and operating QLEDs on flexible substrates persist due to the lack of stable and low-temperature processable charge-injection/-transporting layers with aligned energy levels. In this study, we utilized NiOx nanoparticles that are compatible with flexible substrates as a hole-injection layer (HIL). To enhance the work function of the NiOx HIL, we introduced a self-assembled dipole modifier called 4-(trifluoromethyl)benzoic acid (4-CF3-BA) onto the surface of the NiOx nanoparticles. The incorporation of the dipole molecules through adsorption treatment has significantly changed the wettability and electronic characteristics of NiOx nanoparticles, resulting in the formation of NiO(OH) at the interface and a shift in vacuum level. The alteration of surface electronic states of the NiOx nanoparticles not only improves the carrier balance by reducing the hole injection barrier but also prevents exciton quenching by passivating defects in the film. Consequently, the NiOx-based red QLEDs with interfacial modification demonstrate a maximum current efficiency of 16.1 cd/A and a peak external quantum efficiency of 10.3%. This represents a nearly twofold efficiency enhancement compared to control devices. The mild fabrication requirements and low annealing temperatures suggest potential applications of dipole molecule-modified NiOx nanoparticles in flexible optoelectronic devices.

AGDF-Net: Attention-Gated and Direction-Field-Optimized Building Instance Extraction Network.

Building extraction from high-resolution remote sensing images has various applications, such as urban planning and population estimation. However, buildings have intraclass heterogeneity and interclass homogeneity in high-resolution remote sensing images with complex backgrounds, which makes the accurate extraction of building instances challenging and regular building boundaries difficult to maintain. In this paper, an attention-gated and direction-field-optimized building instance extraction network (AGDF-Net) is proposed. Two refinements are presented, including an Attention-Gated Feature Pyramid Network (AG-FPN) and a Direction Field Optimization Module (DFOM), which are used to improve information flow and optimize the mask, respectively. The AG-FPN promotes complementary semantic and detail information by measuring information importance to control the addition of low-level and high-level features. The DFOM predicts the pixel-level direction field of each instance and iteratively corrects the direction field based on the initial segmentation. Experimental results show that the proposed method outperforms the six state-of-the-art instance segmentation methods and three semantic segmentation methods. Specifically, AGDF-Net improves the objective-level metric AP and the pixel-level metric IoU by 1.1%~9.4% and 3.55%~5.06%.

[In Vitro Degradation Behavior of Absorbable Interface Screws].

The composite material PLGA compounded with ß-tricalcium phosphate (ß-TCP) was prepared by melt blending method, and the absorbable interface screw was prepared by injection molding process. Prepare PBS buffer that simulates human body, conduct in vitro degradation experiments on interface screws according to relevant national and industry standards, then test and characterize interface screws at different time points for degradation of intrinsic viscosity, average molecular weight distribution, mass loss, mechanical properties and thermal properties. According to the degradation performance-time curve, determine the time node at which the interface screw loses the mechanical properties. In this paper, the in vitro degradation behavior of interfacial screws prepared from PLGA and ß-TCP composites was studied in detail, providing a reference and basis for the degradation behavior of absorbable products prepared from PLGA and ß-TCP composites.

Characterization of Multiple Alginate Lyases in a Highly Efficient Alginate-Degrading Vibrio Strain and Its Degradation Strategy.

Alginate is an important polysaccharide in the ocean that supports the growth of marine microorganisms. Many widespread Vibrio species possess alginate lyases and can utilize alginate as a carbon source, but the detailed alginate degradation mechanism in Vibrio remains to be further explored. In this study, we obtained a highly efficient alginate-degrading strain, Vibrio pelagius WXL662, with 11 alginate lyases (VpAly-I to -XI) and further elucidated its molecular mechanism of alginate degradation. Three alginate utilization loci (AUL) were identified in different parts of WXL662's genome, comprising six alginate lyases (VpAly-I, -II, -VIII, -IX, -X, and -XI) and other genes related to alginate degradation. Most of the alginate-degrading genes are strongly induced when alginate is provided as the sole carbon source. Ten alginate lyases (VpAly-I to -X) had been purified and characterized, including six from polysaccharide lyase family 7 (PL7), three from PL17, and one from PL6. These recombinant alginate lyases existing in different cellular locations were active at a wide temperature (10 to 50°C) and pH (4.0 to 9.0) range, with different substrate preferences and diverse degradation products, enabling WXL662 to efficiently utilize alginate in a changing marine environment. Importantly, outer membrane vesicles (OMVs) can act as vectors for alginate lyases (VpAly-II, -V, and -VI) in WXL662. Further investigations of public Vibrio genomes revealed that most alginate-degrading vibrios possess one AUL instead of previously reported "scattered" system. These results emphasize the specific alginate degradation strategy in Vibrio pelagius WXL662, which can be used as a model strain to study the ecological importance of effective alginate-degrading vibrios in the ocean. IMPORTANCE Alginate is an important carbon source in the marine environment, and vibrios are major alginate utilizers. Previous studies focused only on the characteristics of individual alginate lyases in vibrios, but few of them discussed the comprehensive alginate-degrading strategy. Here, we depicted the alginate utilization mechanism and its ecological implications of a highly efficient alginate-degrading Vibrio strain, WXL662, which contained 11 alginate lyases with distinct enzymatic characteristics. Importantly, unlike other vibrios with only one alginate utilization locus (AUL) or the previously reported "scattered" system, three AUL were identified in WXL662. Additionally, the involvement of outer membrane vesicles (OMVs) in the secretion of alginate lyases is proposed for the first time.

Quantification of Intracellular Proteins in Single Cells Based on Engineered Picoliter Droplets.

Unlike conventional bulk measurements, single-cell protein analysis permits quantification of protein expression in individual cells. This has shed light on the cell-to-cell variation in heterogeneous biological systems, such as solid tumors, brain tissues, and developing embryos. Herein, a microfluidic method is developed to profile protein expression in individual cells by performing single-cell intracellular protein immunoassay in picoliter paired droplets. The high sensitivity of single-cell protein analysis on a chip is achieved by the confined reaction volume of picoliter droplets, efficient kinetic characteristics of the immunoassay through active mixing, and minimum single-cell protein loss by integrated operations. The abundance of an intracellular prostate specific antigen at the single-cell level is measured, and then the platform is applied to identify cell types and investigate heterogeneity within cell populations. Overall, a paired chip for single-cell immunoassay establishes a foundation for parallel, sensitive, and integrated protein quantification at the single-cell level and will find wide applications in the field of single-cell proteomics.

Stigmatization related COVID-19 and PTSD among Chinese graduates.

BACKGROUND: Since COVID-19 broke out worldwide, it had caused extensive public health concerns and psychological distress, including PTSD and stigmatization towards recovered patients and people from high-risk areas. However, the association between PTSD, stigmatization and certain related factors have not been confirmed. METHODS: Through cluster random sampling, 946 Chinese graduates were investigated from 5 universities in Shanghai at three months after China lifted its coronavirus lockdown. PTSD symptoms were evaluated with PCL-5. Demographic and disease-related characteristics including stigmatization, educational attainment and working position were collected to assess their association with PTSD. RESULTS: 12.4% graduates were reported significant PTSD symptoms in PCL-5 screening with a cut-off of 33. Graduates with a Master's degree (P = 0.02) or working position like "looking for a job" and "planning to go abroad" (P = 0.038) showed severer stigmatization related to COVID-19. Stigmatization towards both patients recovering from COVID-19 and people from high-risk areas had significant association with PTSD symptoms. Multivariate linear regression analysis showed that stigmatization can explain 5% of variation of PCL-5 scores after controlling gender, age, educational attainments and working position. CONCLUSION: Graduates who were looking for jobs or preparing to go abroad showed more stigmatization related to COVID-19. There was a positive correlation between stigma against COVID-19 and PTSD symptoms. More attention should be paid to the mental health status of graduates who are preparing to go abroad or looking for jobs.

PTSD Among Shidu Parents in China: The Roles of Personality Types and Social Support.

Background: The psychological problems of Shidu Parents (SDP) under the China's One-Child Policy have been documented. The purpose of this study was to investigate the relationships among personality types, social support, and post-traumatic stress disorder (PTSD) in SDP. Methods: The PTSD Checklist-Civilian Version (PCL-C), The Big Five Personality Traits (NEO), and Social Support Revalued Scale (SSRS) were administered to the sample of 149 SDP who were over 50 years old and had lost their only child more than one year ago. Results: Among SDP, mothers were more likely to develop PTSD than fathers (χ2 = 11.16, p < 0.01). Parents who were extraverted had a lower risk of developing PTSD-related symptoms (χ2 = 8.58, p < 0.01), and the effect of neuroticism was significant (χ2 = 23.73, p < 0.01). The more social support parents utilized, the lower the incidence of PTSD (t = 4.56, p < 0.01). The result of multilevel linear regression showed that sex, neuroticism, and objective social support remained significantly different after combining all personality types and social support systems in the same model. Social support partially mediated the relationship between neuroticism and PTSD. Meanwhile, it was a complete mediator between extraversion and PTSD. Conclusions: Female sex/gender, neuroticism, and introversion were risk factors of developing PTSD, while receiving social support protected SDP from developing PTSD symptoms. Losing an only child is undoubtedly an enormous disaster for the family, which has become a huge, unavoidable social problem that must be addressed in China.

Mechanism for KRIT1 release of ICAP1-mediated suppression of integrin activation.

KRIT1 (Krev/Rap1 Interaction Trapped-1) mutations are observed in ∼40% of autosomal-dominant cerebral cavernous malformations (CCMs), a disease occurring in up to 0.5% of the population. We show that KRIT1 functions as a switch for ß1 integrin activation by antagonizing ICAP1 (Integrin Cytoplasmic Associated Protein-1)-mediated modulation of "inside-out" activation. We present cocrystal structures of KRIT1 with ICAP1 and ICAP1 with integrin ß1 cytoplasmic tail to 2.54 and 3.0 Å resolution (the resolutions at which I/σI = 2 are 2.75 and 3.0 Å, respectively). We find that KRIT1 binds ICAP1 by a bidentate surface, that KRIT1 directly competes with integrin ß1 to bind ICAP1, and that KRIT1 antagonizes ICAP1-modulated integrin activation using this site. We also find that KRIT1 contains an N-terminal Nudix domain, in a region previously designated as unstructured. We therefore provide insights to integrin regulation and CCM-associated KRIT1 function.

Chemical profiling and multicomponents quantitative analysis of Panzerina lanata by ultra-fast liquid chromatography with tandem mass spectrometry.

Panzerina lanata is a Chinese medicine with the bioactivity of detumescence and detoxification. In this study, novel qualitative and quantitative methods were established by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry and ultra-high-performance liquid chromatography-triple quadrupole linear ion trap mass spectrometry, respectively. As a result, 20 compounds were identified or tentatively characterized including flavonoids, organic acids, alkaloids, and lignans, five of which were identified for the first time based on the reference standards. The quantitative approach exhibited good linearity (R2  > 0.995), precision (RSDs < 4.97%), stability (RSDs < 4.77%), and recovery (96.04-104.14%). Afterward, this method was implemented to determine 11 flavonoids in four batches of P. lanata. Among them, seven compounds were quantified for the first time. Narcissin was abundant in each batch of P. lanata (average of 10.890-14.230 mg/g) with the highest quantities. The results provide valuable information for quality evaluation.

Floridean Starch and Floridoside Metabolic Pathways of Neoporphyra haitanensis and Their Regulatory Mechanism under Continuous Darkness.

Floridean starch and floridoside are the main storage carbohydrates of red algae. However, their complete metabolic pathways and the origin, function, and regulatory mechanism of their pathway genes have not been fully elucidated. In this study, we identified their metabolic pathway genes and analyzed the changes in related gene expression and metabolite content in Neoporphyra haitanensis under continuous dark conditions. Our results showed that genes from different sources, including eukaryotic hosts, cyanobacteria, and bacteria, were combined to construct floridean starch and floridoside metabolic pathways in N. haitanensis. Moreover, compared with those in the control, under continuous dark conditions, floridean starch biosynthesis genes and some degradation genes were significantly upregulated with no significant change in floridean starch content, whereas floridoside degradation genes were significantly upregulated with a significant decrease in floridoside content. This implies that floridean starch content is maintained but floridoside is consumed in N. haitanensis under dark conditions. This study elucidates the "floridean starch-floridoside" metabolic network and its gene origins in N. haitanensis for the first time.

The influence of risk perception for COVID-19 pandemic on posttraumatic stress disorder in healthcare workers: A survey from four designated hospitals.

The aim of current study was to investigate risk perception of COVID-19 pandemic, sleep quality and time change of leisure activity and their correlations with posttraumatic stress disorder (PTSD) in healthcare workers (HCWs) from four designated hospitals in China. Medical staffs (n = 317) from three designated hospitals in Guangdong Province and one designated hospital in Guangxi Province were surveyed on their demographic information, sleep quality and time change of leisure activity, risk perception of pandemic and PTSD symptoms (by using PTSD checklist for DSM-5 (PCL-5)). Hierarchical regression and structural equation model (SEM) were used to examine the correlated factors of PTSD. The prevalence of high level of PTSD symptoms (PCL-5 > =33, a probable diagnosis of PTSD) was 10.7%. Regression analysis found that risk perception (dread: ß = 0.142, p < 0.01; familiarity: ß = 0.203, p < 0.01), sleep quality (ß = 0.250, p < 0.001), time change of leisure activity (ß = -0.179, p < 0.01), were independently correlated with PTSD severity, which was further confirmed by SEM. Locations of COVID-19-related hazards were significant different in cognitive map of risk perception between groups with high and low levels of PTSD symptoms. Risk perception of COVID-19 pandemic influenced PTSD symptoms in HCWs. Adequate time for leisure activity and good sleep quality protected some HCWs against PTSD symptoms under the influence of pandemic. More researches were warranted to understand the path from pre-factors of risk perception to its psychological consequences among HCWs.

Military-related posttraumatic stress disorder and mindfulness meditation: A systematic review and meta-analysis.

PURPOSE: Posttraumatic stress disorder (PTSD) is a significant global mental health concern, especially in the military. This study aims to estimate the efficacy of mindfulness meditation in the treatment of military-related PTSD, by synthesizing evidences from randomized controlled trials. METHODS: Five electronic databases (Pubmed, EBSCO Medline, Embase, PsychINFO and Cochrane Library) were searched for randomized controlled trials focusing on the treatment effect of mindfulness meditation on military-related PTSD. The selection of eligible studies was based on identical inclusion and exclusion criteria. Information about study characteristics, participant characteristics, intervention details, PTSD outcomes, as well as potential adverse effects was extracted from the included studies. Risk of bias of all the included studies was critically assessed using the Cochrane Collaboration's tool. R Statistical software was performed for data analysis. RESULTS: A total of 1902 records were initially identified and screened. After duplicates removal and title & abstract review, finally, 19 articles in English language with 1326 participants were included through strict inclusion and exclusion criteria. The results revealed that mindfulness meditation had a significantly larger effect on alleviating military-related PTSD symptoms compared with control conditions, such as treatment as usual, present-centered group therapy and PTSD health education (standardized mean difference (SMD) = -0.33; 95% CI [-0.45, -0.21]; p < 0.0001). Mindfulness interventions with different control conditions (active or non-active control, SMD = -0.33, 95% CI [-0.46, -0.19]; SMD = -0.49, 95% CI [-0.88, -0.10], respectively), formats of delivery (group-based or individual-based, SMD = -0.30, 95% CI [-0.42, -0.17], SMD = -0.49, 95% CI [-0.90, -0.08], respectively) and intervention durations (short-term or standard duration, SMD = -0.27, 95% CI [-0.46, -0.08], SMD = -0.40, 95% CI [-0.58, -0.21], respectively) were equally effective in improving military-related PTSD symptoms. CONCLUSION: Findings from this meta-analysis consolidate the efficacy and feasibility of mindfulness meditation in the treatment of military-related PTSD. Further evidence with higher quality and more rigorous design is needed in the future.

PTSD: Past, present and future implications for China.

There has been a long history since human beings began to realize the existence of post-traumatic symptoms. Posttraumatic stress disorder (PTSD), a diagnostic category adopted in 1980 in the Diagnostic and Statistical Manual of Mental Disorders-Ⅲ, described typical clusters of psychiatric symptoms occurring after traumatic events. Abundant researches have helped deepen the understanding of PTSD in terms of epidemiological features, biological mechanisms, and treatment options. The prevalence of PTSD in general population ranged from 6.4% to 7.8% and was significantly higher among groups who underwent major public traumatic events. There has been a long way in the studies of animal models and genetic characteristics of PTSD. However, the high comorbidity with other stress-related psychiatric disorders and complexity in the pathogenesis of PTSD hindered the effort to find specific biological targets for PTSD. Neuroimage was widely used to elucidate the underlying neurophysiological mechanisms of PTSD. Functional MRI studies have showed that PTSD was linked to medial prefrontal cortex, anterior cingulate cortex and sub-cortical structures like amygdala and hippocampus, and to explore the functional connectivity among these brain areas which might reveal the possible neurobiological mechanism related to PTSD symptoms. For now, cognitive behavior therapy-based psychotherapy, including combination with adjunctive medication, showed evident treatment effects on PTSD. The emergence of more effective PTSD pharmacotherapies awaits novel biomarkers from further fundamental research. Several natural disasters and emergencies have inevitably increased the possibility of suffering from PTSD in the last two decades, making it critical to strengthen PTSD research in China. To boost PTSD study in China, the following suggestions might be helpful: (1) establishing a national psychological trauma recover project, and (2) exploring the mechanisms of PTSD with joint effort and strengthening the indigenized treatment of PTSD.

[Mechanism of Potentilla discolor in treating UC by regulating mitochondrial autophagy].

To evaluate the therapeutic effect of Potentilla discolor on 2,4,6-trinitrobenzensulfonic acid(TNBS)-induced experimental ulcerative colitis(UC) in rats and to determine its therapeutic mechanism through mitochondrial autophagy, immune cells, and cytokines. A rat model of UC was established by TNBS-ethanol enema. Rats were divided into six groups: control, UC model, sulfasalazine(positive drug), and high-dose, moderate-dose, and low-dose ethanol extract groups. After 14-day continuous administration of the corresponding drugs, the disease activity index(DAI) and hematoxylin and eosin(HE) were evaluated. The morphological structure of mitochondria was observed by using transmission electron microscope(TEM), mitophagy-related mRNA expression was detected by using Real-time quantitative polymerase chain reaction(qRT-PCR), immune cell differentiation in rat serum was detected by using flow cytometry(FCM), and cytokine expression in colon tissues of rats was detected by protein microarray. The results showed that compared with the model group, each dose group of P. discolor could significantly reduce the DAI of UC model rats, and decrease the degree of inflammatory cells infiltration in the colon tissue of UC model rats. Meanwhile the expressions of T cells and Th cells in the serum increased significantly, the expression of Tc cells in the serum decreased significantly. Transmission electron microscope found that there was fusion of mitochondria and lysosomes in the colon tissue of the administration group. The expressions of mitochondrial autophagy related genes NF-κB, p62 and parkin were significantly increased in colon tissues. The results of protein chip showed that compared with the model group, the high dose group of P. discolor could significantly regulate the expression of cytokines. In conclusion, these results suggested that P. discolor improved TNBS-induced acute ulcerative colitis in rats by regulating the mitochondrial autophagy and the inflammatory factor expression.

Risk factors for PTSD of Shidu parents who lost the only child in a rapid aging process: a cross-sectional study.

BACKGROUND: The elderly population is rising globally, especially in China where a large population base causes the largest number of older adults in the world. Notably, Shidu people who are over the age of 60 and have lost their only child have drawn great public attentions as they become more elderly, medically unstable and worse mentally unhealthy. Posttraumatic stress disorder (PTSD) is one of the most common consequences resulted from the loss of the only child. However, few previous studies have examined PTSD in Shidu older aldults, and the risk factors are a relatively understudied area. Our study aims to estimate the prevalence and potential risk factors of PTSD and improve the possibility of early identifying the high-risk Shidu parents with PTSD, and successively provide timely and effective interventions. METHOD: Based on the register of population statistic information provided by the health family planning commission, 149 participants were enrolled randomly. Data was collected by interviews and questionnaires. Socio-demographic and bereavement-related information and physical health outcomes were obtained. PTSD Checklist-Civilian Version was used to screen for bereavement-related PTSD. RESULT: The morbidity of PTSD reached 30.9%, while in the group of age over 60 the morbidity reached 31.6%. Stratified by potential demographic risk factors, SDPs have significant between-group differences of PTSD. Specially, being women, higher income, losing the single child at older age, more serious medical conditions and being Shidu for a shorter period indicated higher severity of PTSD in SDPs. The single child dying at a older age and from accidence were also significant indicators. Regression analysis showed the gender of SDPs, hospital visits, and the cause of child death significantly predicted the severity of PTSD. CONCLUSION: With the accelerate process of aging, especially in China, Shidu older adults become a group deserved more attentions. PTSD is clearly a possible reaction to the loss of the only child. The gender and hospital visits of the Shidu older adults and the causes of their child's death significantly related to the prevalence of PTSD, which could help to improve the possibility of early intervening.

Biochemical Characterization of a Novel Endo-1,3-ß-Glucanase from the Scallop Chlamys farreri.

Endo-1,3-ß-glucanases derived from marine mollusks have attracted much attention in recent years because of their unique transglycosylation activity. In this study, a novel endo-1,3-ß-glucanase from the scallop Chlamys farreri, named Lcf, was biochemically characterized. Unlike in earlier studies on marine mollusk endo-1,3-ß-glucanases, Lcf was expressed in vitro first. Enzymatic analysis demonstrated that Lcf preferred to hydrolyze laminarihexaose than to hydrolyze laminarin. Furthermore, Lcf was capable of catalyzing transglycosylation reactions with different kinds of glycosyl acceptors. More interestingly, the transglycosylation specificity of Lcf was different from that of other marine mollusk endo-1,3-ß-glucanases, although they share a high sequence identity. This study enhanced our understanding of the diverse enzymatic specificities of marine mollusk endo-1,3-ß-glucanases, which facilitated development of a unique endo-1,3-ß-glucanase tool in the synthesis of novel glycosides.

Two Highly Similar Chitinases from Marine Vibrio Species have Different Enzymatic Properties.

Chitinase, as one of the most important extracellular enzymes in the marine environment, has great ecological and applied values. In this study, two chitinases (Chi1557 and Chi4668) with 97.33% amino acid sequences identity were individually found in Vibrio rotiferianus and Vibrio harveyi. They both were encoding by 561 amino acids, but differed in 15 amino acids and showed different enzymatic properties. The optimal temperature and pH ranges were 45-50 °C and pH 5.0-7.0 for Chi1557, while ~50 °C and pH 3.0-6.0 for Chi4668. K+, Mg2+, and EDTA increased the enzymatic activity of Chi4668 significantly, yet these factors were inhibitory to Chi1557. Moreover, Chi1557 degraded colloidal chitin to produce (GlcNAc)2 and minor GlcNAc, whereas Chi4668 produce (GlcNAc)2 with minor (GlcNAc)3 and (GlcNAc)4. The Kcat/Km of Chi4668 was ~4.7 times higher than that of Chi1557, indicating that Chi4668 had stronger catalytic activity than Chi1557. Furthermore, site-directed mutagenesis was performed on Chi1557 focusing on seven conserved amino acid residues of family GH18 chitinases. Chi1557 was almost completely inactive after Glu154, Gln219, Tyr221, or Trp312 was individually mutated, retained ~50% activity after Tyr37 was mutated, and increased two times activity after Asp152 was mutated, indicating that these six amino acids were key sites for Chi1557.

Developments of prolonged exposure in treatment effect of post-traumatic stress disorder and controlling dropout rate: A meta-analytic review.

Prolonged exposure (PE) has been proved as an efficacious psychological treatment for post-traumatic stress disorder (PTSD). There are mainly two changed formats of PE: the modified PE (mPE) and the PE combined with drug (PE/d). Symptom reduction following these two PE training formats has been reported in the patients with PTSD. However, very little is focusing on the direct comparison of mPE + PE/d and PE. Therefore, this paper aims to compare the mPE + PE/d with PE on the PTSD treatment effect and the dropout rate directly through the meta-analysis. Eighteen studies with total sample size of 1,397 met the final inclusion criteria. The results showed that mPE + PE/d had significantly lower posttreatment PTSD severity than control group (relaxation, wait list, etc.). There was no significant difference between mPE + PE/d and PE on the posttreatment, the follow-up PTSD score, and the posttreatment dropout rate. Compared with PE, lower PTSD symptoms and marginally lower dropout rate following the treatment were observed in the PE/d group. PE/d yielded a significantly larger effect size than mPE when compared with PE on the posttreatment PTSD symptom severity. The significance of the above results would not be changed even if studies causing high heterogeneity were removed. Although PE/d enhanced treatment effect and lowered dropout rate when compared with PE, it was still insufficient to draw the conclusion that formats of adjustments would specifically improve the implementation of PE. Further studies are warranted to develop an easily accomplished and efficacy-guaranteeing PE programme for PTSD patients.