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Catalases play a crucial role in the metabolism of reactive oxygen species (ROS) by converting H2O2 into molecular oxygen and water. They also contribute to virulence and fungal responses to various stresses. Previously, the MrCat1-deletion mutant (ΔMrCat1) was generated using the split-marker method in Metarhizium rileyi. In this study, the Cat1 gene was identified, and its function was evaluated. Under normal culture conditions, there were no significant differences in colony growth or dimorphic switching between ΔMrCat1 and the wild-type (WT) strains. However, under oxidative stress, the colony growth was inhibited, and the yeast-hyphal transition was suppressed in the ΔMrCat1 strain. Hyperosmotic stress did not differ significantly between the two strains. In the ΔMrCat1 strain, microsclerotia (MS) formation was delayed, resulting in less uniform MS size and a 76% decrease in MS yield compared to the WT strain. Moreover, the ΔMrCat1 strain exhibited diminished virulence. Gene expression analysis revealed up-regulation of ΔMrCat1, MrCat2, MrCat4, and MrAox in the ΔMrCat1 strain. These findings indicate that the MrCat1 gene in M. rileyi is essential for oxidative stress tolerance, MS formation, and virulence.
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To explore the prevalence and source of antibiotic resistant genes ï¼ARGsï¼ and pathogenic antibiotic resistant bacteria ï¼PARBï¼ associated with bioaerosols in wastewater treatment plants ï¼WWTPsï¼, metagenomic sequencing and assembly were applied to elucidate the antibiotic resistome of bioaerosols and wastewater in WWTPs. The results showed that more subtypes of ARGs and a higher abundance of PARB were found in bioaerosols from WWTPs and downwind than those from upwind. Multidrug and macB were respectively the most dominant type and subtype of ARGs in bioaerosols from WWTPs. In total, 37 types of PARB carried at least two or more ARG types and were characterized by multiple drug resistance. At the fine grid, aerated tank, and sludge dewatering room, wastewater was the main source of bioaerosol ARGs and PARB. A total of 32 PARB were easily aerosolized in at least one wastewater treatment unit, such as Pseudomonas aeruginosa and Escherichia coli. This study will provide theoretical support for the risk assessment and health protection of antibiotic resistant pollution associated with bioaerosols from WWTPs.
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Aerossóis , Microbiologia do Ar , Eliminação de Resíduos Líquidos , Águas Residuárias , Águas Residuárias/microbiologia , Aerossóis/análise , Eliminação de Resíduos Líquidos/métodos , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Genes Bacterianos , Escherichia coli/isolamento & purificação , Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Resistência Microbiana a Medicamentos/genética , Antibacterianos , Farmacorresistência Bacteriana/genética , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genéticaRESUMO
Lead-free halide perovskites possess excellent photoelectric properties, making them widely used in the photoelectric fields. Herein, lead-free double perovskite crystals (PCs) doped with manganese (Cs2NaInCl6:Mn2+) are successfully prepared by the more energy-efficient crystallization method. The crystals emit bright orange-red light under the ultraviolet (UV) lamp, showing unique optical properties. They have the highest photoluminescence quantum yield of 42.91%. The white light-emitting diodes (LEDs) are fabricated using these perovskite crystals, which show a color rendering index of 92 and external quantum efficiency (EQE) as high as 16.3%. Furtherly, perovskite-modified fiber paper made of aramid chopped fibers (ACFs) and polyphenylene sulfide (PPS) exhibited fluorescent properties under different conditions. This paper combines fiber composite technology with PPS fiber filter bags, which are widely used in environmental protection, for the first time and demonstrates functional fiber filter bags with fluorescent characteristics. This filter bag provides an idea for the automatic detection of industrial filtration. Meanwhile, after being exposed to industrial waste gas for 60 h, the filter bag can maintain superior fluorescence performance. In this study, lead-free double perovskites are synthesized using an efficient method for preparing high-performance LEDs and high-stability fluorescent fibers. Concurrently, the application of perovskites in environmental protection is expanded.
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This study extensively analyzed the bacterial information of biofilms and activated sludge in oxic reactors of full-scale moving bed biofilm reactor-integrated fixed-film activated sludge (MBBR-IFAS) systems. The bacterial communities of biofilms and activated sludge differed statistically (R = 0.624, p < 0.01). The denitrifying genera Ignavibacterium, Phaeodactylibacter, Terrimonas, and Arcobacter were more abundant in activated sludge (p < 0.05), while comammox Nitrospira was more abundant in biofilms (p < 0.05), with an average relative abundance of 8.13%. Nitrospira and Nitrosomonas had weak co-occurrence relationships with other genera in the MBBR-IFAS systems. Potential function analysis revealed no differences in pathways at levels 1 and 2 based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) between biofilms and activated sludge. However, in terms of pathways at level 3, biofilms had more potential in 26 pathways, including various organic biodegradation and membrane and signal transportation pathways. In comparison, activated sludge had more potential in only five pathways, including glycan biosynthesis and metabolism. With respect to nitrogen metabolism, biofilms had greater potential for nitrification (ammonia oxidation) (M00528), and complete nitrification (comammox) (M00804) concretely accounted for methane/ammonia monooxygenase (K10944, K10945, and K10946) and hydroxylamine dehydrogenase (K10535). This study provides a theoretical basis for MBBR-IFAS systems from the perspective of microorganisms.
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BACKGROUND: Osteoarthritis is a prevalent degenerative joint condition typically found in individuals who are aged 50 years or older. In this study, the focus is on PIWI-interacting RNA (piRNA), which belongs to a category of small non-coding RNAs. These piRNAs play a role in the regulation of gene expression and the preservation of genomic stability. The main objective of this research is to examine the expression of a specific piRNA called hsa_piR_019949 in individuals with osteoarthritis, to understand its impact on chondrocyte metabolism within this condition. METHODS: We analyzed piRNA expression in osteoarthritis cartilage using the GEO database. To understand the impact of inflammatory factors on piRNA expression in chondrocytes, we conducted RT-qPCR experiments. We also investigated the effect of piRNA hsa_piR_019949 on chondrocyte proliferation using CCK-8 and clone formation assays. Furthermore, we assessed the influence of piRNA hsa_piR_019949 on chondrocyte apoptosis by conducting flow cytometry analysis. Additionally, we examined the differences in cartilage matrix composition through safranine O staining and explored the downstream regulatory mechanisms of piRNA using transcriptome sequencing. Lentiviral transfection of NEAT1 and NLRP3 was performed to regulate the metabolism of chondrocytes. RESULTS: Using RNA sequencing technology, we compared the gene expression profiles of 5 patients with osteoarthritis to 3 normal controls. We found a gene called hsa_piR_019949 that showed differential expression between the two groups. Specifically, hsa_piR_019949 was downregulated in chondrocytes when stimulated by IL-1ß, an inflammatory molecule. In further investigations, we discovered that overexpression of hsa_piR_019949 in vitro led to increased proliferation and synthesis of the extracellular matrix in chondrocytes, which are cells responsible for cartilage formation. Conversely, suppressing hsa_piR_019949 expression resulted in increased apoptosis (cell death) and degradation of the extracellular matrix in chondrocytes. Additionally, we found that the NOD-like receptor signaling pathway is linked to the low expression of hsa_piR_019949 in a specific chondrocyte cell line called C28/I2. Furthermore, we observed that hsa_piR_019949 can inhibit the expression of a long non-coding RNA called NEAT1 in chondrocytes. We hypothesize that NEAT1 may serve as a downstream target gene regulated by hsa_piR_019949, potentially influencing chondrocyte metabolism and function in the context of osteoarthritis. CONCLUSIONS: PiRNA hsa_piR_019949 has shown potential in promoting the proliferation of chondrocytes and facilitating the synthesis of extracellular matrix in individuals with osteoarthritis. This is achieved by inhibiting the expression of a long non-coding RNA called NEAT1. The implication is that by using hsa_piR_019949 mimics, which are synthetic versions of the piRNA, as a therapeutic approach, it may be possible to effectively treat osteoarthritis.
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Osteoartrite , RNA Longo não Codificante , Humanos , Condrócitos/metabolismo , RNA de Interação com Piwi , RNA Longo não Codificante/metabolismo , Cartilagem/metabolismo , Apoptose/genética , Osteoartrite/genética , Osteoartrite/metabolismoRESUMO
Antibiotic resistome could be loaded by bioaerosols and escape from wastewater or sludge to atmosphere environments. However, until recently, their profile, mobility, bacterial hosts, and risks in submicron bioaerosols (PM1.0) remain unclear. Here, metagenomic sequencing and assembly were employed to conduct an investigation of antibiotic resistome associated with PM1.0 within and around a full-scale wastewater treatment plant (WWTP). More subtypes of antibiotic resistant genes (ARGs) with higher total abundance were found along the upwind-downwind-WWTP transect. ARGs in WWTP-PM1.0 were mainly mediated by plasmids and transposases were the most prevalent mobile genetic elements (MGEs) co-occurring with ARGs. A contig-based analysis indicated that very small proportions (15.32%-19.74%) of ARGs in WWTP-PM1.0 were flanked by MGEs. Proteobacteria was the most dominant host of ARGs. A total of 28 kinds of potential pathogens, such as Pseudomonas aeruginosa and Escherichia coli, carried multiple ARG types. Compared to upwind, WWTP and corresponding downwind were characterized by higher PM1.0 resistome risk. This study emphasizes the vital role of WWTPs in discharging PM1.0-loaded ARGs and antibiotic resistant pathogens to air, and indicates the need for active safeguard procedures, such as that employees wear masks and work clothes, covering the main emission sites, and collecting and destroying of bioaerosols.
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Antibacterianos , Purificação da Água , Humanos , Antibacterianos/farmacologia , Genes Bacterianos , Bactérias/genética , Águas ResiduáriasRESUMO
The antibiotic-resistant pollution in size-segregated bioaerosols from wastewater treatment plants (WWTPs) is of increasing concern due to its public health risks, but an elaborate review is still lacking. This work overviewed the profile, mobility, pathogenic hosts, source, and risks of antibiotic resistance genes (ARGs) in size-segregated bioaerosols from WWTPs. The dominant ARG type in size-segregated bioaerosols from WWTPs was multidrug resistance genes. Treatment units that equipped with mechanical facilities and aeration devices, such as grilles, grit chambers, biochemical reaction tanks, and sludge treatment units, were the primary sources of bioaerosol antibiotic resistome in WWTPs. Higher enrichment of antibiotic resistome in particulate matter with an aerodynamic diameter of <2.5 µm, was found along the upwind-downwind-WWTPs gradient. Only a small portion of ARGs in inhalable bioaerosols from WWTPs were flanked by mobile genetic elements. The pathogens with multiple drug resistance had been found in size-segregated bioaerosols from WWTPs. Different ARGs or antibiotic resistant bacteria have different aerosolization potential associated with bioaerosols from various treatment processes. The validation of pathogenic antibiotic resistance bacteria, deeper investigation of ARG mobility, emission mechanism of antibiotic resistome, and development of treatment technologies, should be systematically considered in future.
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Antibacterianos , Purificação da Água , Antibacterianos/farmacologia , Águas Residuárias , Resistência Microbiana a Medicamentos/genética , Esgotos/microbiologia , Bactérias , Genes BacterianosRESUMO
Objective: This study aimed to investigate stigmatizing attitudes toward depression, schizophrenia, and general anxiety disorder (GAD) among caregivers of patients with mental disorders in China. Methods: A cross-sectional study was conducted among 607 caregivers in China, using vignettes that described three mental illnesses. Data on the caregivers' attitudes and other people's attitudes toward individuals with mental disorders and their willingness to come in contact with people with mental disorders were collected. Results: In the three vignettes, caregivers agreed that positive outcomes outnumbered negative outcomes. The top two statements endorsing the stigma were "the person could snap out of the problem" and "people with this problem are dangerous." In the section for perceived stigma, caregivers in the GAD vignette agreed that most people believed this problem is not a real medical illness, compared to schizophrenia. The rates of the statement endorsing unpredictability were significantly different in the schizophrenia (57.2%) and depression (45.5%) vignette, in comparison to the GAD (45.6%) vignette. For personal stigma, the caregivers tended to avoid people described in the depression vignette more often than in the GAD vignette. The caregivers were most unwilling to let the person described in the vignettes marry into their family, especially in the schizophrenia vignette. Conclusion: Despite the stigma and desire for social distance associated with schizophrenia, depression, and GAD, caregivers often expect positive outcomes. Actions should be taken to improve caregivers' knowledge about mental health and reduce the stigma.
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Cuidadores , Transtornos Mentais , Humanos , Estudos Transversais , Estereotipagem , Atitude , ChinaRESUMO
Antibiotic resistome can be carried by the bioaerosols and propagate from wastewater treatment plants (WWTPs) to the atmosphere, but questions remain regarding their mobility, bacterial hosts, source, and resistome risk. Here, fine particulate matter (PM2.5) was collected within and around a large WWTP and analyzed by the metagenomic assembly and binning. PM2.5 was discovered with increasing enrichment of total antibiotic resistance genes (ARGs), potentially mobile ARGs, and antibiotic-resistant bacteria (ARB) along the WWTP-downwind-upwind gradient. Some ARGs were found to be flanked by certain mobile genetic elements and generally mediated by plasmids in WWTP-PM2.5. Totally, 198 metagenome assembled genomes assigning to seven phyla were identified as the ARB, and a contig-based analysis indicated that 32 pathogens were revealed harboring at least two ARGs. Despite disparate aerosolization potentials of ARGs or ARB at different WWTP units, high resistome risks were found, along with the dominant contribution of wastewater for airborne ARGs (44.79-62.82%) and ARB (35.03-40.10%). Among the detected WWTP matrices, the sludge dewatering room was characterized by the highest resistome risk associated with PM2.5. This study underscores the dispersion of ARGs and ARB from WWTPs to the atmosphere and provides a reference for managing risks of antibiotic resistance.
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Genes Bacterianos , Águas Residuárias , Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Bactérias/genética , Atmosfera , Material Particulado , AntibacterianosRESUMO
PURPOSE OF REVIEW: The situation of China drug use has seen dramatic changes in recent years. The aim of this review is to give a perspective of the current situation of drug abuse, the problems associated with it, and the strategy to control it in China. RECENT FINDINGS: The number of registered drug users and newly discovered drug users had declined for 5 consecutive years, Moreover, the scaling down of drug trafficking and drug-related crimes had been seen for recent years. There are four main drug treatment modalities in China. The drug abuse and its related problems in China face new challenges, including the impact of the coronavirus disease 2019 pandemic, the role of compulsory treatment is overemphasized, the voluntary treatment facilities and community treatment cannot meet the requirements of Chinese society, and the coordination among government departments in drug control and treatment in China need to improved. SUMMARY: With years of the joint efforts, the overall drug situation kept improving. The drug abuse and its related problems in China still is a problem, and require effective and immediate interventions.
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COVID-19 , Transtornos Relacionados ao Uso de Substâncias , Humanos , COVID-19/complicações , Transtornos Relacionados ao Uso de Substâncias/terapia , Transtornos Relacionados ao Uso de Substâncias/complicações , China/epidemiologiaRESUMO
It is a great challenge to develop photocatalysts for the degradation of organic pollutants in the aqueous environment, especially those with excellent catalytic performance under visible light conditions. In this work, using graphene oxide (GO) as an electron shuttle agent and carrier, a hybrid of ZIF-8/NH2-MIL-125(Ti) and GO (ZIF-8/NH2-MIL-125(Ti)/GO) was prepared by a simple two-step solvothermal method. The morphology, structure, and combination of the synthesized catalysts were studied. The results showed that graphene oxide and ZIF-8 formed an in situ load on NH2-MIL-125(Ti). The construction of hybrid materials significantly improved the catalytic activity of NH2-MIL-125(Ti) in the visible light range. The degradation activity of the synthesized catalyst was further tested with reactive red dye. The results showed that the catalyst exhibited excellent catalytic removal efficiency for active red, with a degradation rate of 99.8% within 2 h. The prepared hybrid materials have good application prospects in the field of organic pollutant treatment in water.
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Poluentes Ambientais , Grafite , Óxidos , Titânio , Água , Corantes , Eletrônica , LuzRESUMO
All-inorganic metal halide perovskites are widely studied because of their excellent photoelectric properties. However, due to the toxicity of CsPbX3 (X = Cl, Br, I) perovskites, it is difficult to apply them on a large scale. The lead-free nature and air stability make Cs2SnX6 (X = Cl, Br, I) perovskites possible candidates to replace CsPbX3 perovskites. Herein, we report the perovskite crystals (PCs) based on Te(IV)-doped Cs2SnCl6: Cs2Sn1-xTexCl6. Cs2Sn1-xTexCl6 PCs showed yellow emission under a 365 nm ultraviolet lamp. The photoluminescence quantum yield (PLQY) of Cs2Sn0.94Te0.06Cl6 PCs was 57.09%, which was proposed to be from the triplet Te(IV) ion 3P1 â 1S0 self-trapping excitons (STE) recombination. The perovskite crystals can be used to fabricate light-emitting diodes (LEDs). The fiber paper prepared from aramid chopped fibers (ACFs) and polyphenylene sulfide (PPS) fibers showed a bright yellow light under 365 nm ultraviolet light after being post-processed with Cs2Sn1-xTexCl6 PCs solution. The ACFs/PPS compound fiber paper modified with Cs2Sn1-xTexCl6 PCs maintained exceptional optical properties and could be stored in air for more than 4500 h. The fluorescence performance of the modified ACFs/PPS compound fiber paper could be applied to fluorescence anti-counterfeiting. The modification strategy and the applications in this work will provide a good choice for studying the optical performance of perovskites and broaden the application of ACFs/PPS compound fiber paper.
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Esquizofrenia , Humanos , Cognição , Emoções , Reconhecimento Psicológico , Esquizofrenia/complicações , Percepção SocialRESUMO
BACKGROUND: Major depressive disorder (MDD) with comorbid anxiety is very common and is associated with worse clinical outcomes. MDD patients at different ages of onset may have different clinical features and associated factors. The aim of this study was to investigate the prevalence of anxiety and related factors in MDD patients at different ages of onset. METHODS: A total of 1718 first-episode and drug-naïve (FEDN) MDD patients were recruited. The cutoff point for early-adulthood onset (EAO) and mid-adulthood onset (MAO) was the first depressive episode before or after age 45 years. Clinical features (depressive, anxiety and psychiatric symptoms) and some metabolic parameters were collected. RESULTS: There was no significant difference in the prevalence of anxiety between EAO patients (50.7 %) and MAO patients (55.7 %). For EAO patients, regression analysis showed that TSH levels, TgAb levels, and TC levels were significantly associated with anxiety. For MAO patients, regression analysis showed that anxiety was associated with HDL-c levels and impaired glucose metabolism. Furthermore, suicide attempts, psychotic symptoms, and depression severity were correlated with anxiety in both groups. LIMITATIONS: Our cross-sectional study cannot explain the causal relationship between anxiety and related factors in MDD patients at different ages of onset. CONCLUSIONS: This study revealed that the clinical characteristics and factors associated with anxiety in MDD patients differed according to age of onset, and therefore age of onset needs to be considered while treating anxiety.
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Ansiedade , Transtorno Depressivo Maior , Adulto , Humanos , Pessoa de Meia-Idade , Ansiedade/epidemiologia , Estudos Transversais , Transtorno Depressivo Maior/psicologia , População do Leste Asiático , Monoaminoxidase , PrevalênciaRESUMO
Structural colors can be used in fabric coloring due to their bright color and non-fading properties. However, it is still a challenge to construct structural color on high crystallinity, smooth surfaced and yellow colored aramid fabrics. Herein, for the first time, photonic crystals (PCs) with structural color were constructed on aramid fabrics by introducing dopamine to modify aramid fabrics and synthesizing monodisperse high refractive index zinc sulfide nanoparticles (ZnS). The influence of the PC coatings on the structural color, mechanical properties, and thermal stability of the structurally colored aramid fabrics or fibers was further investigated. Moreover, due to the excellent catalytic properties of ZnS and the slow photon effects of PCs, the structurally colored fabrics showed good photocatalytic properties, which will be beneficial in reusing the catalysts, which is crucial to their application in the coloring of fabrics but also facilitates the recycling of waste PC coated aramid fabrics.
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Objective: To compare the functional and radiological outcome of combine compression interlocking intramedullary nail (InterTan) and proximal femoral nail anti-rotation II (PFNA-II) in the treatment of elderly patients with intertrochanteric fractures. Methods: As a retrospective cohort study, records of 88 patients with intertrochanteric fractures treated in our hospital from January 1st, 2019 to July 31st, 2021 were retrospectively reviewed. According to treatment records, it included 45 patients treated with InterTan (Group-A) and 43 patients treated with PFNA-II (Group-B). The operation safety and functional rehabilitation of the two groups were compared and analyzed. Results: This study included 88 patients with intertrochanteric fractures (mean [SD] age, 68.72 [0.10] years at baseline), of whom 52 (59.09%) were males and 36 (40.91%) were females. Operation time and intraoperative blood loss in Group-B were less than Group-A, while fracture healing time was shorter in Group-A. The fracture separation distance was measured four weeks after the operation. The widening rate of the fracture line in Group-A was lower than Group-B (4.4% vs.18.6%; P<0.05). The incidence of complications in Group-A was lower than Group-B (4.4% vs.18.6%; P<0.05). At three, six and twelve months after the operation, the Harris hip score of the two groups was higher than at discharge (P<0.05), with no significant difference between groups (P>0.05). Conclusions: We found no significant difference in the functional outcome in elderly patients with intertrochanteric fractures treated with InterTan and PFNA-II. Early fracture healing and reduced complication rate however has been noted with InterTan.
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BACKGROUND: Both major depressive disorder (MDD) and impaired fasting glucose (IFG) are associated with metabolic abnormalities and anxiety, but few studies have investigated the relationship between abnormal metabolism and anxiety in first-episode and drug-naïve (FEDN) MDD patients with IFG. This study investigated the psychological status, metabolic properties, the prevalence and influencing factors of anxiety symptoms in the FEDN MDD patients with IFG. METHODS: A total of 1718 FEDN MDD outpatients were recruited. Sociodemographic and suicide data were collected for each participant. The Positive and Negative Syndrome Scale (PANSS), Hamilton Depression Rating Scale (HAMD), and Hamilton Anxiety Rating Scale (HAMA) were used to assess patients' clinical symptoms. Fasting blood glucose, lipids, body mass index (BMI), and thyroid function-related indicators were also measured. RESULTS: FEDN MDD patients with IFG (IFG group) had higher psychotic symptoms, suicide attempts, HAMD score, and HAMA score than FEDN MDD patients without IFG (NIFG group). There were also significant differences in blood lipids, BMI, and thyroid function indicators between the two groups. The prevalence of anxiety symptoms in the IFG group was 20.9 %, which was significantly higher than that in the NIFG group (10.4 %). Furthermore, anxiety symptoms were significantly associated with female, marital status, psychotic symptoms, suicide attempts, and low high-density lipoprotein (HDL-C). CONCLUSION: FEDN MDD patients with anxiety who have IFG are more likely to have problems with thyroid function, lipid metabolism, psychotic symptoms and suicide attempts, especially in female patients. Prevention of these problems should be enhanced when treating such patients.
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Transtorno Depressivo Maior , Humanos , Feminino , Transtorno Depressivo Maior/diagnóstico , Prevalência , Estudos Transversais , Ansiedade/epidemiologia , Lipídeos , Jejum , GlucoseRESUMO
BACKGROUND: Benzodiazepine receptor agonists (BZRAs) are commonly used clinically and data on their hazardous use from large populations of psychiatric patients is limited. AIMS: To assess the current status of hazardous BZRA use and related factors in Chinese out-patient psychiatric settings. METHOD: The study included out-patients with at least one BZRA prescription from five psychiatric settings in east, central and west China in 2018. Demographic and prescription information were extracted from the electronic prescription database. We defined the co-occurrence of overdose and long-term use as hazardous use, and patients whose recorded diagnoses did not meet any indications approved by the Chinese Food and Drug Administration as over-indication users. Additionally, 200 hazardous users were randomly selected for follow-up interview to confirm the actual situation. RESULTS: Among 720 054 out-patients, 164 450 (22.8%) had at least one BZRA prescription; 55.9% of patients were prescribed over-indication and 3% were defined as hazardous users. Multilevel multivariate regression analysis with hospital as a random effect showed that factors associated with hazardous use were older age (18-64 years: ß = 0.018; 95% CI 0.013-0.023; >65 years: ß = 0.015; 95% CI 0.010-0.021), male (ß = 0.005, 95% CI 0.003-0.007), over-indication (ß = 0.013, 95% CI 0.012-0.015), more out-patient visits (ß = 0.006, 95% CI 0.006-0.006) and more visits to different doctors (ß = 0.007, 95% CI 0.007-0.008); 98.5% of hazardous users (197/200) could not be contacted. CONCLUSIONS: BZRAs are commonly used and there is a relatively large proportion of over-indication users among Chinese psychiatric out-patients. However, only a small proportion of hazardous users were detected. The study highlights how to use prescription data to support improvements in clinical practice.