The deleterious effects and potential therapeutic strategy of fluorene-9-bisphenol on circadian activity and liver diseases in zebrafish and mice.

Increasing evidence indicates that disturbance of the clock genes, which leads to systemic endocrine perturbation, plays a crucial role in the pathogenesis of metabolic and liver diseases. Fluorene-9-bisphenol (BHPF) is utilized in the manufacturing of plastic materials but its biological effects on liver homeostasis remain unknown. The impacts and involved mechanisms of BHPF on the liver diseases, metabolism, and circadian clock were comprehensively studied by zebrafish and mouse models. The therapeutic effect of melatonin (MT) was also verified. Zebrafish and mouse models with either acute exposure (0.5 and 1 µmol/L, 1-4 days post-fertilization) or chronic oral exposure (0.5 and 50 mg/(kg·2 days), 30 days) were established with various BHPF concentrations. Herein, we identified a crucial role for estrogenic regulation in liver development and circadian locomotor rhythms damaged by BHPF in a zebrafish model. BHPF mice showed chaos in circadian activity through the imbalance of circadian clock component Brain and Muscle Aryl hydrocarbon receptor nuclear translocator-like 1 in the liver and brain. The liver sexual dimorphic alteration along with reduced growth hormone and estrogens played a critical role in damaged glucose metabolism, hepatic inflammation, and fibrosis induced by BHPF. Besides, sleep improvement by exogenous MT alleviated BHPF-related glucose metabolism and liver injury in mice. We proposed the pathogenesis of metabolic and liver disease resulting from BHPF and promising targeted therapy for liver metabolism disorders associated with endocrine perturbation chemicals. These results might play a warning role in the administration of endocrine-disrupting chemicals in everyday life and various industry applications.

Design, synthesis, in vitro and in vivo evaluation and molecular docking study of novel pleuromutilin derivatives as antibacterial agents.

14 novel pleuromutilin derivatives were designed and synthesized as inhibitors against Staphylococcus aureus (S. aureus). The modification was focused on the C22 position of pleuromutilin. We conducted the characterization, in vitro and in vivo biological assessment of the compounds. Compound 18 exhibited the best antibacterial effect against MRSA (MIC = 0.015 µg/mL, MBC = 0.125 µg/mL). Compound 18 was further studied by time-kill kinetic and post-antibiotic effect (PAE) approaches. Besides, most compounds exhibited low cytotoxicity to RAW 264.7 cells. Compound 18 displayed decent bactericidal activity in vivo (-0.51 log10 CFU/mL). Molecular docking study indicated that compound 18 could be located stably at the ribosome (ΔGb = -7.30 kcal/mol). The results revealed that compound 18 might be further developed into a novel antibiotic.

Effects of fluorene-9-bisphenol exposure on anxiety-like and social behavior in mice and protective potential of exogenous melatonin.

Fluorene-9-bisphenol (BHPF) is widely used in the manufacture of plastic products and potentially disrupts several physiological processes, but its biological effects on social behavior remain unknown. In this study, we investigated the effects of BHPF exposure on anxiety-like and social behavior in female mice and the potential mechanisms, thereby proposing a potential therapy strategy. We exposed female Balb/c mice to BHPF by oral gavage at different doses (0.5, 50 mg/kg bw/2-day) for 28 days, which were found BHPF (50 mg/kg) exposure affected motor activity in the open field test (OFT) and elevated cross maze (EPM), resulting in anxiety-like behaviors, as well as abnormal social behavioral deficits in the Social Interaction Test (SIT). Analysis of histopathological staining results showed that BHPF exposure caused damage to hippocampal neurons in the CA1/CA3/DG region and decreased Nissl pyramidal neurons in the CA1/CA3 regions of the hippocampus, as well as a decrease in parvalbumin neuron expression. In addition, BHPF exposure upregulated the expression of excitatory and inhibitory (E/I) vesicle transporter genes (Vglut1, Vglut2, VGAT, GAD67, Gabra) and axon growth gene (Dcc) in the mouse hippocampus. Interestingly, behavioral disturbances and E/I balance could be alleviated by exogenous melatonin (15 mg/kg bw/2-day) therapy. Our findings suggest that exogenous melatonin may be a potential therapy with protective potential for ameliorating or preventing BHPF-induced hippocampal neuronal damage and behavioral disturbances. This study provided new insight into the neurotoxicological effects on organisms exposed to endocrine-disrupting chemicals and aroused our vigilance in current environmental safety about chemical use.

Alleviative effects of the parthenolide derivative ACT001 on insulin resistance induced by sodium propionate combined with a high-fat diet and its potential mechanisms.

The increasing side effects of traditional medications used to treat type II diabetes have made research into the development of safer and more effective natural medications necessary. ACT001, a derivative of parthenolide, has been shown to have good anti-inflammatory and antitumor effects; however, its role in diabetes is unclear. The short-chain fatty acid propionate is a common food preservative that has been found to cause disturbances in glucose metabolism in mice and humans. This study aimed to investigate whether sodium propionate could aggravate insulin resistance in obese mice and cause diabetes and to study the alleviative effects and potential mechanisms of action of ACT001 on insulin resistance in diabetic mice. Type II diabetic mice were adminietered sodium propionate combined with a high-fat diet (HFD + propionate) by gavage daily for four weeks. Biochemical analysis showed that ACT001 significantly affected blood glucose concentration in diabetic mice, mainly by downregulating the expression of phosphoenolpyruvate carboxykinase 2 and glucose-6-phosphatase. Meanwhile, the level of fatty acid-binding protein 4 in the liver was significantly decreased. ACT001 has a protective effect on the liver and adipose tissue of mice. In addition, the results of the running wheel experiment indicated that ACT001 alleviated the circadian rhythm disorder caused by insulin resistance to a certain extent. This study revealed the potential mechanism by which ACT001 alleviates insulin resistance and provides ideas for developing natural antidiabetic drugs.

Characterization of kidneys in patients with systemic sclerosis by multi-parametric magnetic resonance quantitative imaging.

PURPOSE: To determine the usefulness of multiparametric magnetic resonance (MR) quantitative imaging in characterizing the kidneys in systemic sclerosis (SSc) patients. MATERIAL AND METHODS: Forty-six SSc patients (47.9 ± 12.8 years, 40 females) and 22 age- and sex- matched healthy volunteers (46.1 ± 13.8 years, 20 females) were recruited and underwent renal MR imaging by acquiring blood oxygen level dependent and saturated multi-delay renal arterial spin labeling (SAMURAI) sequences. The T2* value, T1 value, renal blood flow (RBF), arterial bolus arrival time (aBAT), and tissue bolus arrival time (tBAT) of renal cortex were measured and compared among diffuse cutaneous SSc (dcSSc) and limited cutaneous SSc (lcSSc) groups and healthy controls using One-way ANOVA and analyzed by logistic regression. RESULTS: Compared to healthy volunteers, SSc patients with normal estimated glomerular filtration rate (n = 40) had significantly lower T2* value (P = 0.026) in the left renal cortex, longer T1 value (right: P = 0.015; left: P = 0.023), lower RBF (right: P < 0.001; left: P < 0.001), and shorter tBAT (right: P < 0.001; left: P = 0.005) in both right and left renal cortex after adjusting for demographics. The dcSSc patients (n = 23) had significantly lower RBF in both right (226.7 ± 65.2 mL/100 g/min vs. 278.2 ± 73.5 mL/100 g/min, P = 0.022) and left (194.5 ± 71.5 mL/100 g/min vs. 252.7 ± 84.4 mL/100 g/min, P = 0.020) renal cortex compared to the lcSSc patients (n = 23) after adjusting for demographics, but the significance of the difference was attenuated after further adjusting for modified Rodnan skin score and digital ulcers. CONCLUSION: Multi-parametric MR quantitative imaging, particularly multi-delay ASL perfusion imaging, is a useful technique for characterizing the kidneys and classification of SSc patients.

Diffusing capacity of lungs for carbon monoxide associated with subclinical myocardial impairment in systemic sclerosis: A cardiac MR study.

BACKGROUND: Systemic sclerosis (SSc) is characterised by microvascular and fibrotic lesions, which are located not only in skin but also in lungs and heart. OBJECTIVE: This study aimed to investigate the association between lung function and myocardial T1 values using cardiac MR (CMR) imaging in patients with SSc without cardiovascular symptoms. METHODS: The SSc patients and age- and sex-matched healthy subjects underwent CMR. The cardiac function and native T1 values of myocardium and lung function were measured. Spearman's rank correlations and linear regression analyses were performed to determine the association between lung function and myocardial T1. RESULTS: Forty-five SSc patients (aged 47.7±13.2 years, 40 females) and 23 (aged 46.0±14.4 years, 20 females) healthy subjects were enrolled. SSc patients exhibited considerably higher native T1 values compared with healthy subjects (1305.9±49.8 ms vs 1272.6±37.6 ms, p=0.006). Linear regression analysis revealed that decrease of diffusing capacity of lungs for carbon monoxide (DLCO) in SSc patients was notably associated with myocardial native T1 value before (ß -1.017; 95% CI -1.883 to -0.151; p=0.022) and after adjusting for confounding factors (ß -1.108; 95% CI -2.053 to -0.164; p=0.023). Moderate-to-severe decrease of DLCO was found to be significantly associated with myocardial native T1 value (ß 48.006; 95% CI 17.822 to 78.190; p=0.003) after adjusting for confounding factors. CONCLUSION: DLCO inversely correlates with myocardial native T1 values in SSc patients, particularly moderate-to-severely decreased DLCO, suggesting that DLCO might be a potential indicator for subclinical myocardial impairment in SSc patients.

Functional, physicochemical, and structural properties of the hydrolysates derived from the abalone (Haliotis discus subsp hannai Ino) foot muscle proteins.

This study was conducted to investigate functional, physicochemical, and structural properties of abalone foot muscle proteins (AFPs) and their hydrolysates (HAFPs) obtained using animal protease (HA), papain (HPP), and Protamex® (HP) at different time points. The HA-hydrolysate obtained after 0.5 h of treatment demonstrated the highest solubility at pH 7.0 (84.19%); the HPP-hydrolysate at 4 h exhibited the highest degree of hydrolysis (11.4%); the HPP-hydrolysate at 0.5 h had the highest oil holding capacity (2.62 g/g) and emulsion stability index (39.73 min), and the HP-hydrolysate at 4 h had the highest emulsifying activity index (93.23 m2/g) and foaming stability (91.45%); Regarding the physicochemical properties, the HPP-hydrolysates revealed the largest particle size, higher absolute zeta potential, and superior interfacial activity. Structural characterization demonstrated the enzymolysis-based changes in the composition and the secondary structure of the AFPs. These results provide practical support for the theoretical basis of the use of AFPs as a source of nutritive proteins in the food industry.

Characterization and Assessment of Projection Probability Density Function and Enhanced Sampling in Self-Collimation SPECT.

We have recently reported a self-collimation SPECT (SC-SPECT) design concept that constructs sensitive detectors in a multi-ring interspaced mosaic architecture to simultaneously improve system spatial resolution and sensitivity. In this work, through numerical and Monte-Carlo simulation studies, we investigate this new design concept by analyzing its projection probability density functions (PPDF) and the effects of enhanced sampling, i.e. having rotational and translational object movements during imaging. We first quantitatively characterize PPDFs by their widths and edge slopes. Then we compare the PPDFs of an SC-SPECT and a series of multiple-pinhole SPECT (MPH-SPECT) systems and assess the impact of PPDFs - combined with enhanced sampling - on image contrast recovery coefficient and variance through phantom studies. We show the PPDFs of SC- SPECT have steeper edges and a wider range of width, and these attributes enable SC-SPECT to achieve better performance.

Inhibition of voltage-gated sodium ion channel by corannulene and computational inversion blockage underlying mechanisms.

Corannulene (Cor), a special carbon material, evidenced strong protein binding capacity which regulating lysozyme crystallization and controlling reactive oxygen species (ROS) generation. Ion channel protein play role in regulating ion channel functions to affect physiological functions. However, the interaction between Cor and ion channel protein have not been studied. In this study, PEG/Cor nanoparticles (PEG/Cor Nps) were prepared by mPEG-DSPE. The PEG/Cor Nps localized in cytoplasm and produced cytotoxicity at high concentration. Whole cell patch clamp examined ion channel functions after incubate PEG/Cor Nps with PC-12 cell. we found that PEG/Cor Nps inhibited voltage-gated Na+ ion channels in a dose- and time-dependent manner but not act on voltage-gated K+ ion channels. The potential mechanisms were revealed by all-atom molecular dynamic (MD) simulations. The results showed that PEG/Cor Nps block the pore of sodium ion channel protein due to dose- and time-dependent accumulation. Besides, the orientation angle (θ) configuration of PEG/Cor Nps will be inverted with the accumulation to generate two blocking mechanisms. Different from other carbon nanomaterials, the blockage mechanism of PEG/Cor Nps provides novel insights into the mechanisms of interaction between carbon nanomaterials and protein.

ESRG is critical to maintain the cell survival and self-renewal/pluripotency of hPSCs by collaborating with MCM2 to suppress p53 pathway.

The mechanisms of self-renewal and pluripotency maintenance of human pluripotent stem cells (hPSCs) have not been fully elucidated, especially for the role of those poorly characterized long noncoding RNAs (lncRNAs). ESRG is a lncRNA highly expressed in hPSCs, and its functional roles are being extensively explored in the field. Here, we identified that the transcription of ESRG can be directly regulated by OCT4, a key self-renewal factor in hPSCs. Knockdown of ESRG induces hPSC differentiation, cell cycle arrest, and apoptosis. ESRG binds to MCM2, a replication-licensing factor, to sustain its steady-state level and nuclear location, safeguarding error-free DNA replication. Further study showed that ESRG knockdown leads to MCM2 abnormalities, resulting in DNA damage and activation of the p53 pathway, ultimately impairs hPSC self-renewal and pluripotency, and induces cell apoptosis. In summary, our study suggests that ESRG, as a novel target of OCT4, plays an essential role in maintaining the cell survival and self-renewal/pluripotency of hPSCs in collaboration with MCM2 to suppress p53 signaling. These findings provide critical insights into the mechanisms underlying the maintenance of self-renewal and pluripotency in hPSCs by lncRNAs.

Novel coronavirus infection and its vaccination-related ocular disease / 国际眼科杂志(Guoji Yanke Zazhi)

The continuous pandemic coronavirus disease 2019(COVID-19)caused by severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)is a serious threat to human life and health because of high infectious pathogenicity, and it also has posed a new challenge to the current medical model. Many literatures have shown that these changes range from the more common ocular surface diseases such as inflammation of the cornea, conjunctiva, and sclera, to the relatively rare paracentral acute middle maculopathy and acute macular neuroretinopathy. For patients with ocular symptoms as the first or accompanying symptoms of SARS-CoV-2 infection, how to identify the correlation between ocular manifestations and SARS-CoV-2 infection is undoubtedly a serious challenge for ophthalmologists. In this review, the ocular pathology caused by both SARS-CoV-2 infection and vaccination was discussed, covering pathological changes in the ocular surface, uvea, retina and macula, and cranial nerves.

Allelopathic Effects of Amomum villosum Lour. Volatiles from Different Organs on Selected Plant Species and Soil Microbiota.

Amomum villosum Lour. is a perennial herb of the Zingiberaceae family, which is widely distributed in Xishuangbanna, Yunnan Province in Southwest China. Large amounts of volatile components contained in this plant enter the surrounding atmosphere and soil through volatilization, foliar leaching, root exudation, and residue decomposition. However, the ecological role of these compounds is currently unclear. The aim of this study was to compare the differences in the composition of volatile oils from stems, leaves, and young fruits of A. villosum, identify chemicals that had allelopathic effects, and explore the effects of the oil on the diversity and composition of soil microbiomes. Volatile oils were obtained by steam distillation and characterized by gas chromatography−mass spectrometry, and then were tested for allelopathic activity using seedlings of Lactuca sativa L. and Lolium perenne L. as test species. The results showed that the oils from stems and leaves were rich in monoterpene hydrocarbons, unlike the oxygenated monoterpenes which dominated oils from young fruits. Leaves > stems > young fruits: this was the order of the allelopathic effects of volatile oils from various A. villosum organs. Among the four main chemical components in the oils, only α-pinene, which is abundant in leaves, had a stronger allelopathic action than the crude oils, implying that it might be a potential allelochemical. Experiments on soil microorganisms indicated that 3.0 mg/mL oil had the greatest effect on the structure of the soil fungal community. It can be concluded that A. villosum is capable of releasing allelochemicals which affect the growth of other plant species and the diversity and community structure of soil microorganisms.

Exposure to melamine cyanuric acid in adult mice caused motor activity and skeletal muscle energy metabolism disorder.

Thyroid hormone has a variety of physiological functions and plays an important role in the development of central nervous system, skeletal muscle and lung, as well as body temperature regulation. Skeletal muscle is a key determinant of basal metabolic rate and systemic energy metabolism. It contains Myopsin (SLN) which plays an important role in muscle heat production and energy metabolism. Melamine cyanuric acid (MCA) is an important component of the new flame retardant, but also a chemical interfering substance that can affect the endocrine in the body. It is mainly distributed in nylon and other flame retardant substances. Therefore, in this study, male mice were exposed to MCA at 10, 20 and 30 mg/kg for four weeks. We explored the effects of MCA exposure on skeletal muscle morphology, thermogenic gene expression and motor activity to explore whether MCA exposure could induce skeletal muscle hyperthermia and energy metabolism disorders and its underlying mechanisms. The results showed that the motor activity of male mice exposed to MCA was decreased, the morphology of skeletal muscle tissue was impaired, and the levels of morphological and thermogenic genes in skeletal muscle were destroyed. These findings are intended to provide a preliminary reference for studying the effects of MCA exposure on thermogenesis and energy metabolism in adult mice.

Study of 99mTc absorption on micro-sized ion exchange resins to achieve high activity for SPECT.

In single-photon emission computed tomography (SPECT), a micro-sized 99mTc source is routinely used for performance measurement, geometry calibration, and system matrix generation. Therefore, a micro-sized source is critical in nuclear instrument production and quality control. Standard methods can only produce a point source with a large size and low total activity, as they are limited by the concentration of the 99mTc solution. The absorption of 99mTc on ion exchange resins has been used; however, few studies have quantitatively evaluated the absorption process and optimized the source activity. This paper proposes a procedure for producing a micro-sized 99mTc resin source with a super-high concentration, as well as a method for the fast measurement of the point source time-activity curve (TAC). Experiments on two resin point sources with diameters of 0.681 mm and 0.326 mm were carried out. Two semi-empirical models, including the first kinetic model and the pseudo-second-order rate equation model, were used to fit TACs. The results show the first kinetic model fit better, which suggests an acquisition time of 2-4 h is needed for optimization. The verification experiment demonstrates a resin point source with a diameter of 0.35 mm and total activity of 10.6 mCi (i.e., 59.1 Ci/mL concentration) was produced.

Artificial intelligence-based literature data warehouse for vaccine safety / 中华流行病学杂志

Objective: To establish a sustainable updated literature data warehouse for global vaccine safety assessment, and provide data support for evidence-based vaccine safety assessment. Methods: Semi-automated construction and updating of a literature data warehouse were achieved through the continuous integration of standard operating steps of evidence-based reviews with artificial intelligence technologies. Following the standard procedure of a systematic literature review, the literatures about vaccine safety assessment published before November 29, 2020 were retrieved from 9 databases including OVID, Scopus, Web of Science, Cochrane Library, and ClinicalTrails.org in English and Wanfang, CNKI, VIP, and SinoMed in Chinese. Literatures were screened for two rounds in a semi-automatic manner (by artificial intelligence literature processing system and manual work) according to the inclusion/exclusion criteria. Furthermore, the literatures were classified according to the types of vaccines and adverse events. The updating strategy was established, and the literature data warehouse was updated regularly. Experts were organized to select specific vaccine safety topics and carry out special demonstration studies. Results: More than 0.41 million articles were retrieved. According to the inclusion/exclusion criteria, 23 304 articles were included after two rounds of screening. At present, we have selected and completed three prior topics as demonstration studies, including the systematic review of "DPT (diphtheria, pertussis and tetanus) vaccine and encephalopathy/encephalitis", and the classified management of literatures about allergic purpura and brachial plexus neuritis. Conclusions: The sustainable updated literature data warehouse of vaccine safety can provide high-quality research data for vaccine safety research, including evidence support for immunization related policy-making and adjustment and vaccine safety-related methodological research or clinical tool development; and further demonstration studies can provide references for building a new methodological framework system for timely and efficient completion of the evidence-based assessment of vaccine safety.

Effects of occupational mercury exposure on the immune function of workers / 中国职业医学

@#Objective To investigate the effects of mercury on T lymphocytes and serum immune indexes of workers with Methods occupational mercury exposure. A total of 45 workers with occupational mercury exposure were selected as the ， mercury exposure group and 47 workers without occupational mercury exposure were selected as the control group using the judgment sampling method. Cold atomic absorption spectrometry was used to detect the urinary mercury level of the two groups. （ ） +， + +， + + - + Flow cytometry was used to detect the proportion of cluster of differentiation CD 3 CD3CD4 CD3CD8 and CD3CD19 ， - （ - ） - （ - ） cells in peripheral blood and the levels of tumor necrosis factor α TNF α and interleukin 8 IL 8 in serum. The levels of （ ） ， Results immunoglobulin Ig A IgG and IgM in serum were measured by immune nephelometry. The urinary mercury level of （ ： vs ，P ） individuals in the mercury exposed group was higher than that of the control group median 92.7 13.2 μg/g Cr <0.01 . The +， + +， - + proportion of CD3 CD3CD4 CD3CD19 cells in peripheral blood and serum IgG level in the mercury exposed group （ P ）， - - （ P ） decreased all <0.05 and the serum TNF α and IL 8 levels increased all <0.01 compared with the control group. Urinary - + mercury level was negatively correlated with the proportion of CD3CD19 cells in peripheral blood and serum IgG level in the ［ （r） ， ， P ］， study subjects Spearman correlation coefficient S were −0.21 and −0.31 respectively all <0.05 and positively - - （r ， ， P ） ， correlated with serum TNF α and IL 8 levels S were 0.36 and 0.39 respectively all <0.05 . However the urinary mercury （ P ）， +， + +， level was neither correlated with IgA and IgM levels in serum all >0.05 nor with the proportion of CD3 CD3CD4 + + （ P ） Conclusion CD3CD8 cells in peripheral blood all >0.05 . Occupational exposure to mercury can lead to abnormal ， changes in peripheral blood T lymphocyte subsets B lymphocytes and serum immune factors in workers. The mercury load of occupational mercury exposure workers may impact their immune function.

Glyoxalase 1 Confers Susceptibility to Schizophrenia: From Genetic Variants to Phenotypes of Neural Function.

This research aimed to investigate the role of glyoxalase 1 (Glo-1) polymorphisms in the susceptibility of schizophrenia. Using the real-time polymerase chain reaction (PCR) and spectrophotometric assays technology, significant differences in Glo-1 messenger ribonucleic acid (mRNA) expression (P = 3.98 × 10-5) and enzymatic activity (P = 1.40 × 10-6) were found in peripheral blood of first-onset antipsychotic-naïve patients with schizophrenia and controls. The following receiver operating characteristic (ROC) curves analysis showed that Glo-1 could predict the schizophrenia risk (P = 4.75 × 10-6 in mRNA, P = 1.43 × 10-7 in enzymatic activity, respectively). To identify the genetic source of Glo-1 risk in schizophrenia, Glo-1 polymorphisms (rs1781735, rs1130534, rs4746, and rs9470916) were genotyped with SNaPshot technology in 1,069 patients with schizophrenia and 1,023 healthy individuals. Then, the impact of risk polymorphism on the promoter activity, mRNA expression, and enzymatic activity was analyzed. The results revealed significant differences in the distributions of genotype (P = 0.020, false discovery rate (FDR) correction) and allele (P = 0.020, FDR correction) in rs1781735, in which G > T mutation significantly showed reduction in the promoter activity (P = 0.016), mRNA expression, and enzymatic activity (P = 0.001 and P = 0.015, respectively, GG vs. TT, in peripheral blood of patients with schizophrenia) of Glo-1. The expression quantitative trait locus (eQTL) findings were followed up with the resting-state functional magnetic resonance imaging (fMRI) analysis. The TT genotype of rs1781735, associated with lower RNA expression in the brain (P < 0.05), showed decreased neuronal activation in the left middle frontal gyrus in schizophrenia (P < 0.001). In aggregate, this study for the first time demonstrates how the genetic and biochemical basis of Glo-1 polymorphism culminates in the brain function changes associated with increased schizophrenia risk. Thus, establishing a combination of multiple levels of changes ranging from genetic variants, transcription, protein function, and brain function changes is a better predictor of schizophrenia risk.

Comparison of resting-state spontaneous brain activity between treatment-naive schizophrenia and obsessive-compulsive disorder.

BACKGROUND: Schizophrenia (SZ) and obsessive-compulsive disorder (OCD) share many demographic characteristics and severity of clinical symptoms, genetic risk factors, pathophysiological underpinnings, and brain structure and function. However, the differences in the spontaneous brain activity patterns between the two diseases remain unclear. Here this study aimed to compare the features of intrinsic brain activity in treatment-naive participants with SZ and OCD and to explore the relationship between spontaneous brain activity and the severity of symptoms. METHODS: In this study, 22 treatment-naive participants with SZ, 27 treatment-naive participants with OCD, and sixty healthy controls (HC) underwent a resting-state functional magnetic resonance imaging (fMRI) scan. The amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo) and degree of centrality (DC) were performed to examine the intrinsic brain activity of participants. Additionally, the relationships among spontaneous brain activity, the severity of symptoms, and the duration of illness were explored in SZ and OCD groups. RESULTS: Compared with SZ group and HC group, participants with OCD had significantly higher ALFF in the right angular gyrus and the left middle frontal gyrus/precentral gyrus and significantly lower ALFF in the left superior temporal gyrus/insula/rolandic operculum and the left postcentral gyrus, while there was no significant difference in ALFF between SZ group and HC group. Compared with HC group, lower ALFF in the right supramarginal gyrus/inferior parietal lobule and lower DC in the right lingual gyrus/calcarine fissure and surrounding cortex of the two patient groups, higher ReHo in OCD group and lower ReHo in SZ group in the right angular gyrus/middle occipital gyrus brain region were documented in the present study. DC in SZ group was significantly higher than that in HC group in the right inferior parietal lobule/angular gyrus, while there were no significant DC differences between OCD group and HC group. In addition, ALFF in the left postcentral gyrus were positively correlated with positive subscale score (r = 0.588, P = 0.013) and general psychopathology subscale score (r = 0.488, P = 0.047) respectively on the Positive and Negative Syndrome Scale (PANSS) in SZ group. ALFF in the left superior temporal gyrus/insula/rolandic operculum of participants with OCD were positively correlated with compulsion subscale score (r = 0.463, P = 0.030) on the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS). The longer the illness duration in SZ group, the smaller the ALFF of the left superior temporal gyrus/insula/rolandic operculum (Rho = 0.-492, P = 0.020). The longer the illness duration in OCD group, the higher the ALFF of the right supramarginal gyrus/inferior parietal lobule (Rho = 0.392, P = 0.043) and the left postcentral gyrus (Rho = 0.385, P = 0.048), and the lower the DC of the right inferior parietal lobule/angular gyrus (Rho = - 0.518, P = 0.006). CONCLUSION: SZ and OCD show some similarities in spontaneous brain activity in parietal and occipital lobes, but exhibit different patterns of spontaneous brain activity in frontal, temporal, parietal, occipital, and insula brain regions, which might imply different underlying neurobiological mechanisms in the two diseases. Compared with OCD, SZ implicates more significant abnormalities in the functional connections among brain regions.