Prevalence of prolonged grief disorder and its symptoms among bereaved individuals in China:a systematic review and meta-analysis

Background The prevalence of prolonged grief disorder(PGD)and its symptoms among the bereaved population in China vary considerably.Aims This meta-analysis aims to estimate the prevalence of PGD and its symptoms among bereaved individuals in China.Methods We conducted a literature search in major Chinese and English databases from their inception to 4 October 2023,for cross-sectional studies on the prevalence of PGD or its symptoms in bereaved Chinese individuals.The risk of bias of the included studies and certainty of the evidence were assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Studies Reporting Prevalence Data(‘JBI checklist’)and the Grading of Recommendations,Assessment,Development and Evaluations(GRADE),respectively.The‘metaprop’package in R V.4.1.2 was used to synthesise the prevalence.Results A total of 28 studies involving 10994 bereaved individuals were included in the analysis,with JBI checklist scores between 3 and 7.The combined prevalence(95%confidence interval)of PGD and its symptoms was 8.9%(4.2%to 17.6%)and 32.4%(18.2%to 50.8%),respectively.PGD and its symptoms were most prevalent among those who had lost their only child(22.7%)and those bereaved by earthquakes(80.4%),respectively.The GRADE system assigned a very low certainty level to the evidence for the pooled prevalence of PGD and its symptoms.Conclusions The pooled prevalence of PGD and its symptoms indicate a potential high need for grief counselling services among bereaved individuals in China.This need is particularly pronounced in those who have lost their only child and those bereaved due to earthquakes.Further methodologically rigorous studies are needed to provide more accurate prevalence estimates.PROSPERO registration number CRD42023432553.

Single-nucleus transcriptome profiling of prefrontal cortex induced by chronic methamphetamine treatment

Background Methamphetamine(METH)addiction causes a huge burden on society.The prefrontal cortex(PFC),associated with emotion and cognitive behaviours,is also involved in addiction neurocircuitry.Although bulk RNA sequencing has shown METH-induced gene alterations in the mouse PFC,the impact on different cell types remains unknown.Aims To clarify the effects of METH treatment on different cell types of the PFC and the potential pathways involved in METH-related disorders.Methods We performed single-nucleus RNA sequencing(snRNA-seq)to examine the transcriptomes of 20465 nuclei isolated from the PFC of chronic METH-treated and control mice.Main cell types and differentially expressed genes(DEGs)were identified and confirmed by RNA fluorescence in situ hybridization(FISH).Results Six main cell types were identified depending on the single-cell nucleus sequencing;of particular interest were the mature oligodendrocytes in the PFC.The DEGs of mature oligodendrocytes were enriched in the myelin sheath,adenosine triphosphate(ATP)metabolic process,mitochondrial function and components,and so on.The messenger RNA levels of Aldoc and Atp5l(FISH)and the protein level of the mitochondrial membrane pore subunit TOM40(immunofluorescence)decreased in the mature oligodendrocytes.Fast blue staining and transmission electron microscopy image indicated myelin damage,and the myelin thickness decreased in METH brains.Conclusions snRNA-seq reveals altered transcriptomes of different cell types in mouse PFC induced by chronic METH treatment,underscoring potential relationships with psychiatric disorders.

Identification of a functional 339 bp Alu insertion polymorphism in the schizophrenia-associated locus at 10q24.32

Genome-wide association studies(GWAS)have identified multiple single nucleotide polymorphisms(SNPs)or small indels robustly associated with schizophrenia;however,the functional risk variations remain largely unknown.We investigated the 10q24.32 locus and discovered a 339 bp Alu insertion polymorphism(rs71389983)in complete linkage disequilibrium(LD)with the schizophrenia GWAS risk variant rs7914558.The presence of the Alu insertion at rs71389983 strongly repressed transcriptional activities in in vitro luciferase assays.This polymorphism may be a target for future mechanistic research.Our study also underlines the importance and necessity of considering previously underestimated Alu polymorphisms in future genetic studies of schizophrenia.