Objective In order to shorten the transparency time of clear,unobstructed brain imaging cocktails and computational analysis(CUBIC),improve the transparency efficiency,and explore the possibility of applying hydrophilic tissue transparency technique,this study was conducted to optimize the perfusion of CUBIC technique and compare it with four hydrophilic tissue clearing method in terms of tissue transparency effect,transparency time,area change,volume change and adeno-associated virus(AAV)fluorescence retention.Methods Brain,liver,spleen and kidney of 6 adult Institute of Cancer Research(ICR)mice were subjected to clearing treatment by SeeDB,FRUIT,ScaleS and CUBIC method,respectively.The area and gray value of the samples were measured by Image J 1.8.0,and the volume before and after transparency was measured by drainage method to compare the transparency effect,time and size deformation of each group.Perfusion optimization of the CUBIC was performed by improving the perfusion rate with the optimal perfusion dose,each group of the experimental sample size was 6.Fluorescence preservation by different techniques was evaluated by injecting AAV in the motor cortex of 16 adult mice and taking the cervical spinal segments for transparency treatment after four weeks,and the fluorescence photographs were measured by Image J 1.8.0 to measure the mean fluorescent intensity.Results The optimal perfusion rate and dose of CUBIC was 15 ml/min and 200 ml respectively.For transparency ability and speed,the perfusion CUBIC had the lowest mean gray value and took the shortest time,while CUBIC consumed the longest time,and SeeDB,FRUIT,and ScaleS did not show good transparency ability.In terms of area and volume changes,several techniques showed different degrees of expansion after transparency of tissues or organs.In terms of fluorescence retention,perfusion CUBIC showed the best retention of green fluorescent protein(GFP)fluorescence signal,followed by CUBIC,ScaleS,FRUIT,and SeeDB.Conclusion Perfusion CUBIC technique shows the best tissue transparency,the shortest transparency time,and the most AAV fluorescence retention compared with other techniques.

Objective:Under the background of "new medical science", to construct a whole-process education path with "education as the driving force - moral cultivation as the core", and to provide a decision-making basis for the reform, innovation, and development of humanistic quality education in medical colleges.Methods:Five-year clinical medical students (freshman to fifth graders) from Qiqihar Medical University were selected as the research objects. The evaluation model and questionnaire of humanistic quality of clinical medical students were constructed by literature analysis. The Questionnaire Star platform was used to investigate and collect data by random sampling of clinical medical undergraduates, and the data results were analyzed by SPSS 26.0 to explore the path of building the whole-process education.Results:The empirical research on the cultivation of humanistic quality of medical students showed that the average humanistic attitude score of medical students was (3.47±0.75) points. From the perspective of gender, the scores of humanistic cognition, attitude, and behavior of male students were 2.81, 3.68, and 3.22 points, respectively, which were all significantly higher than those of female students (2.52, 3.22, and 2.95 points, respectively) ( P<0.05). The data from freshmen to the fifth graders showed that humanistic cognition, attitude, and behavior scores all presented an increasing trend with the grade. Using the "Knowledge, Attitude/Belief, Practice" model, it was found that the cognitive rate of humanistic quality of medical students was relatively ideal, and the awareness rate of medical students in different grades was different. The cross analysis showed that the effect of ideological morality and political literacy education on medical students in medical colleges had a significant cross-relationship with multiple choice questions. Conclusion:The humanistic quality of clinical medical students needs to be improved, and the cultivation of medical humanistic quality should run through the whole process from the first year to the fifth year, so as to improve the comprehensive training of professional ability and promote the all-round development of medical students.

In recent years, more and more forensic genetics laboratories have begun to apply massively parallel sequencing (MPS) technology, that is, next-generation sequencing (NGS) technology, to detect common forensic genetic markers, including short tandem repeat (STR), single nucleotide polymorphism (SNP), the control region or whole genome of mitochondrial DNA (mtDNA), as well as messenger RNA (mRNA), etc., for forensic practice, such as individual identification, kinship analysis, ancestry inference and body fluid identification. As the most widely used genetic marker in forensic genetics, STR is currently mainly detected by capillary electrophoresis (CE) platform. Compared with CE platform, MPS technology has the advantages of simultaneous detection of a large number of genetic markers, massively parallel detection of samples, the polymorphism of sequence detected by NGS makes STR have the advantages of higher resolution and system efficiency. However, MPS technology is expensive, there is no uniform standard so far, and there are problems such as how to integrate MPS-STR data with the existing CE-STR database. This review summarizes the current status of the application of MPS technology in the detection of STR genetic markers in forensic genetics, puts forward the main problems that need to be solved urgently, and prospects the application prospect of this technology in forensic genetics.
DNA Fingerprinting/methods* ; Forensic Genetics/methods* ; Genetic Markers ; High-Throughput Nucleotide Sequencing/methods* ; Microsatellite Repeats/genetics* ; Polymorphism, Single Nucleotide ; Sequence Analysis, DNA ; Technology

Postmortem interval （PMI） estimation has always been an important and difficult issue in the field of forensic pathology. In recent years, research progress on the estimation of PMI using RNA specific variation patterns after death has been made by researchers at home and aboard. This paper summarizes the specific application methods of messenger RNA and non-coding RNA for PMI estimation based on the literatures and discusses the existing problems and development trends, in order to provide technical reference for related studies and estimation practice.
Autopsy ; Forensic Pathology ; Humans ; Postmortem Changes ; RNA, Messenger/genetics* ; RNA, Untranslated ; Time Factors

Objective Quantitative analysis and comparison of the expression of ribonucleic acid （RNA） from frozen organs and formaldehyde-fixed and paraffin-embedded （FFPE） tissues. Methods Frozen specimens of human brain, myocardium and liver tissues as well as FFPE samples at different postmortem intervals were collected and mass concentration of RNA was extracted and detected. Reverse transcription-quantitative polymerase chain reaction （RT-qPCR） technology was used to analyze the amplification efficiency and relative expression of each RNA marker. Results The mass concentration and integrity of RNA extracted from FFPE samples were relatively low compared with frozen specimens. The amplification efficiency of RNA markers was related with RNA species and the length of amplification products. Among them, glyceraldehyde-3-phosphate dehydrogenase （GAPDH） and β-actin （ACTB） with relatively long amplification products failed to achieve optimal amplification efficiency, whereas 5S ribosomal RNA （5S rRNA） achieved ideal amplification efficiency and showed quite stable expression across various tissues, therefore it was chosen as internal reference marker. The expression quantity of GAPDH and ACTB in frozen specimens with longer postmortem intervals and in FFPE samples with relatively long amplification products was decreased. The expressions of tissue-specific microRNAs （miRNAs）, GAPDH and ACTB with relatively short amplification products had consistency in the same tissues and FFPE samples. Conclusion Through standardizing the RT-qPCR experiment, selecting the appropriate RNA marker and designing primers of appropriate product length, RNA expression levels of FFPE samples can be accurately quantified.
DNA Primers ; Formaldehyde ; Gene Expression Profiling ; Humans ; MicroRNAs/analysis* ; Myocardium ; Paraffin Embedding ; RNA/analysis* ; Real-Time Polymerase Chain Reaction/standards*

Objective: To compare the quality of RNA extracted from fresh and formalin-fixed paraffin-embedded (FFPE) brain tissues and to explore the long non-coding RNA (lncRNA) expression level. Methods: FFPE samples stored under various conditions and paired frozen brain tissues were collected and total RNA qualities were then detected. Amplification efficiency (AE) and expression stability of each RNA marker were calculated and analyzed based on real-time quantitative PCR. After selecting reference biomarkers, normalized △ Ct values of candidate makers within different amplicon size were measured to assess the possibility of lncRNA quantification in FFPE tissues. Results: The purity of RNA extracted from FFPE was relatively high, but the RNA integrity was lower than fresh samples. All biomarkers were successfully amplified and amplification efficiencies of long-chain RNA markers were correlated with amplicon sizes, sample treatment and preservation conditions, namely temperature and storage time. 5S, miR-9 and miR-125b achieved optimal AE and showed quite stable expression in all specimens, therefore they were chosen as control markers. Compared with fresh samples, the △ Ct values of only 2 lncRNA (HAR1F and MALAT1-L, whose amplicon size were both higher than 200 bp, respectively) increased in the FFPE samples kept in 4 ℃, while in FFPE tissues kept in room temperature, increments of the △ Ct values were significant for most target genes except for short amplicon markers (<60 bp), which showed consistently stable expression in all brain specimens. Conclusion: RNA integrity is affected by sample treatment and preservation conditions, but lncRNA expression levels in FFPE tissues can be accurately quantificated by using optimal amplicon sizes and considerable reference markers.

Objective: To investigate the association of the abnormal length of human Y chromosome with semen quality and the outcome of assisted reproductive technology (ART). METHODS: Based on the karyotype, we assigned the patients undergoing ART to a normal control, a long Y chromosome (Y>18), and a short Y chromosome group (Y<22). We compared the semen parameters and numbers of embryos and high-quality embryos among the three groups of patients and performed statistical analysis of the obtained data using Chi-square distribution and t-test. RESULTS: Compared with the control, the Y>18 group showed a significantly lower incidence rate of asthenozoospermia (31.03% vs 8.33%, P <0.05) and a larger number of high-quality embryos (5.46 ± 4.54 vs 7.40 ± 5.49, P<0.05). Both the incidence rate of azoospermia and number of total embryos were remarkably lower in the control than in the Y<22 group (1.87% vs 16.47%, P <0.05; 8.60 ± 7.03 vs 10.00 ± 6.58, P<0.05). No statistically significant differences were found in the pregnancy rate between the Y>18 and Y<22 groups (P>0.05). CONCLUSIONS Short Y chromosome may affect spermatogenesis, but the length of Y chromosome does not negatively influence the outcome of ART.
Asthenozoospermia ; genetics ; Azoospermia ; genetics ; Chi-Square Distribution ; Chromosomes, Human, Y ; Female ; Humans ; Karyotype ; Karyotyping ; Male ; Pregnancy ; Pregnancy Rate ; Reproductive Techniques, Assisted ; Semen ; Semen Analysis ; standards ; Sex Chromosome Aberrations ; Spermatogenesis ; Treatment Outcome

OBJECTIVES: To explore the correlation between early postmortem interval （PMI） and eight RNA markers of rat's brain at different temperatures. METHODS: Total 222 SD rats were randomly divided into control group （PMI=0 h） and four experimental groups. And the rats in the experimental groups were sacrificed by cervical dislocation and respectively kept at 5 ℃, 15 ℃, 25 ℃ and 35 ℃ in a controlled environment chamber. The RNA was extracted from brain tissues, which was taken at 9 time points from 1 h to 24 h postmortem. The expression levels of eight markers, β-actin, GAPDH, RPS29, 18S rRNA, 5S rRNA, U6 snRNA, miRNA-9 and miRNA-125b, were detected using real-time fluorescent quantitative PCR, respectively. Proper internal reference was selected by geNorm software. Regression analysis of normalized RNA markers was performed by SPSS software. Mathematical model for PMI estimation was established using R software. Another 6 SD rats with known PMI were used to verify the mathematical model. RESULTS: 5S rRNA, miR-9 and miR-125b were suitable as internal reference markers for their stable expression. Both β-actin and GAPDH had well time-dependent degradation patterns and degraded continually with prolongation of PMI in 24 h postmortem. The mathematical model of the variation of ΔCt values with PMI and temperature was set up by R software and the model could be used for PMI estimation. The average error rates of model validation using β-actin and GAPDH were 14.1% and 22.2%, respectively. CONCLUSIONS The expression levels of β-actin and GAPDH are well correlated with PMI and environmental temperature. The mathematical model established in present study can provide references for estimating early PMI under various temperature conditions.
Actins/metabolism* ; Animals ; Autopsy ; Brain/pathology* ; Genetic Markers ; MicroRNAs ; Models, Theoretical ; Postmortem Changes ; RNA Stability ; RNA, Small Nuclear ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction ; Regression Analysis ; Software ; Temperature ; Time Factors

OBJECTIVES: To explore the correlation between the expression levels of several RNA markers in human brain tissue and early postmortem interval （PMI）. METHODS: Twelve individuals with known PMI （range from 4.3 to 22.5 h） were selected and total RNA was extracted from brain tissue. Eight commonly used RNA markers were chosen including β-actin, GAPDH, RPS29, 18S rRNA, 5S rRNA, U6 snRNA, miRNA-9 and miRNA-125b, and the expression levels were detected in brain tissue by real-time fluorescent quantitative PCR. The internal reference markers with stable expression in early PMI were screened using geNorm software and the relationship between its expression level and some relevant factors such as age, gender and cause of death were analyzed. RNA markers normalized by internal reference were inserted into the mathematic model established by previous research for PMI estimation using R software. Model quality was judged by the error rate calculated with estimated PMI. RESULTS: 5S rRNA, miRNA-9 and miRNA-125b showed quite stable expression and their expression levels had no relation with age, gender and cause of death. The error rate of estimated PMI using β-actin was 24.6%, while GAPDH was 41.0%. CONCLUSIONS 5S rRNA, miRNA-9 and miRNA-125b are suitable as internal reference markers of human brain tissue owing to their stable expression in early PMI. The expression level of β-actin correlates well with PMI, which can be used as an additional index for early PMI estimation.
Actins/analysis* ; Autopsy ; Brain/metabolism* ; Humans ; MicroRNAs/analysis* ; Models, Theoretical ; Postmortem Changes ; RNA Stability ; RNA, Ribosomal, 18S/analysis* ; RNA, Ribosomal, 5S/analysis* ; RNA, Small Nuclear/analysis* ; Real-Time Polymerase Chain Reaction ; Software

OBJECTIVE: To observe the changes of relative expression of myocardial various RNAs in rats died of different causes and their relationship with PMI. METHODS: The rat models were established in which the rats were sacrificed by broken neck, asphyxia, and hemorrhagic shock. Total RNAs were extracted from myocardium. The quantitative real time PCR was used to calculate threshold cycle values of RNAs including glyceraldehyde-3-phosphate dehydrogenase (GAPDH), beta-actin, inducible nitric oxide synthase (iNOS), hypoxia-inducible factor-1 (HIF-1), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and U6 small nuclear RNA (U6 snRNA) and to study the changes of the relative expressions of various indexes with PMI. RESULTS: U6 snRNA with stable expression level could be used as appropriate internal control. In the early PMI, the relative expression of GAPDH, HIF-1, iNOS, TNF-alpha, and IL-6 more characteristically increased in groups of asphyxia and hemorrhagic shock than in group of broken neck, but the quantity of beta-actin decreased in all groups. In the late PMI, all the relative expressions significantly declined in correlation with the degradation of RNA. CONCLUSION The characteristic changes of each RNA expression can be used as references to estimate PMI in deaths by different causes.
Actins ; Animals ; Cause of Death ; Cytokines/metabolism* ; Disease Models, Animal ; Enzymes/metabolism* ; Glyceraldehyde-3-Phosphate Dehydrogenases ; Myocardium/metabolism* ; Nitric Oxide Synthase Type II ; RNA/metabolism* ; RNA, Small Nuclear ; Rats ; Shock, Hemorrhagic ; Tumor Necrosis Factor-alpha