Candidate biomarkers in brown adipose tissue for post-mortem diagnosis of fatal hypothermia

Post-mortem diagnosis of fatal hypothermia (FHT) is challenging in forensic practice because traditional morphological and biochemical methods lack specificity. Recent studies have reported that brown adipose tissue (BAT) is activated during cold-induced non-shivering thermogenesis in mammals, but BAT has not been used to diagnose FHT. The aim of this study was to identify novel biomarkers in BAT for FHT based on morphological changes and differential protein expression. Two FHT animal models were created by exposing mice to 4 or -20 °C at 50% humidity. Morphologically, the unilocular lipid droplet content was significantly increased in BAT of FHT model mice compared with that of control mice. Proteomics analysis revealed a total of 283 and 266 differentially expressed proteins (DEPs) between the 4 or -20 °C FHT subgroups and control group, respectively. In addition, 140 proteins were shared between the FHT subgroups. GO and KEGG analyses revealed that the shared DEPs were mainly enriched in pathways associated with metabolism, oxidative phosphorylation, and thermogenesis. Further screening (|log2FC| > 1.6, q-value (FDR) < 0.05) identified GMFB, KDM1A, DDX6, RAB1B, SHMT-1, CLPTM1, and LMF1 as candidate biomarkers of FHT. Subsequent validation experiments were performed in FHT model mice using classic immunohistochemistry and western blotting. RAB1B and GMFB expression was further verified in BAT specimens from human cases of FHT. The results demonstrate that BAT can be used as a target organ for FHT diagnosis employing RAB1B and GMFB as biological markers, thus providing a new strategy for the post-mortem diagnosis of FHT in forensic practice.

Single-cell landscape and clinical outcomes of infiltrating B cells in colorectal cancer

B cells constitute a major component of infiltrating immune cells in colorectal cancer (CRC). However, the characteristics of B cells and their clinical significance remain unclear. In this study, using single-cell RNA sequencing and multicolour immunofluorescence staining experiments, we identified five distinct subtypes of B cells with their marker genes, distribution patterns and functional properties in the CRC tumour microenvironment. Meanwhile, we found a higher proportion of IgG plasma cells in tumour sites than that in adjacent normal mucosal tissues. In addition, the CXCL13-producing CD8⁺ T cells in the tumour tissues could promote the formation of tertiary lymphoid structure (TLS) B cells, and the CCL28-CCR10 axis is pivotal for IgG plasma cell migration from the periphery of TLSs to the tumour stroma. Finally, we identified four distinct colon immune classes (CICs: A-D) and found that CD20⁺ B cells within TLSs were enriched in one immune-inflamed or hot tumour group (CIC D). This B cell-rich group, which was characterized by strong antigen presentation, IgG plasma cells accumulation, microsatellite instability-high (MSI-H) and high tumour mutation burden (TMB-H), as well as immunosuppressive property in particular, might become a potential predictive biomarker for future immunotherapy. Additionally, in an immunotherapy cohort, patients with the enrichment of B cells and TLSs were demonstrated to obtain significant therapeutic advantages. Together, our findings provide the detailed landscape of infiltrating B cells and their potential clinical significance in CRC.

Effects of Postmortem Hemolysis and Ultrafiltration on Creatinine Detection Results

OBJECTIVES

To investigate the interference of postmortem hemolysis on the detection of creatinine and whether ultrafiltration can reduce the interference.

METHODS

A total of 33 non-hemolyzed whole blood samples from the left heart were collected. Hemolyzed samples with 4 hemoglobin mass concentration gradients H1-H4 were artificially prepared. Ultrafiltration was performed on each hemolyzed sample. Creatinine concentrations in non-hemolyzed serum (baseline serum), hemolyzed samples and ultrafiltrate were detected. Bias (B), Pearson correlation and receiver operator characteristic (ROC) of baseline creatinine concentration between before and after ultrafiltration were analyzed.

RESULTS

As the hemoglobin mass concentration increased, B of the hemolyzed samples in the H1-H4 groups gradually increased, the |B| was 2.41(0.82, 8.25)-51.31(41.79, 188.25), reaching a maximum of 589.06%, and there was no statistically significant between the creatinine concentration and the baseline creatinine concentration (P=0.472 7, r=0.129 5). After ultrafiltration of hemolyzed samples, the interference of creatinine concentration in ultrafiltrate was significantly reduced, the |B| was 5.32(2.26, 9.22)-21.74(20.06, 25.58), reaching a maximum of 32.14%, and there was a positive correlation with baseline creatinine concentration (P<0.05, r=0.918 2). In the hemolyzed samples of H3 and H4 groups, there were 7 false-positive samples and 1 false-negative sample; in the ultrafiltrate samples, there were no false-positive sample and 1 false-negative sample. ROC analysis results showed the hemolyzed samples were lack of diagnostic value (P=0.117 5).

CONCLUSIONS

The postmortem hemolysis significantly interferes creatinine detection results of blood samples, ultrafiltration can reduce hemolysis-induced interference in postmortem creatinine detection.

Research Progress of Exosomal microRNA in Cardiovascular Disease and Its Forensic Application Prospects

Exosomal microRNAs (miRNAs) are miRNAs that are mediated by exosomes to achieve cell-to-cell communication, and they are widespread in organisms. In recent years, the key role of the multiple biological functions of exosomal miRNAs in the occurrence and development of cardiovascular diseases has been confirmed by a large number of studies, which has become a hot spot in clinical and basic research. Sudden cardiac death caused by cardiovascular disease is one of the important contents in forensic medical identification. This article introduces the research progress of cardiovascular disease prediction, treatment and prognosis on exosomal miRNA. The prospects of the application in forensic medical identification are discussed.

Application of Postmortem Biochemistry Analysis in Forensic Medicine

In recent years, postmortem biochemistry analysis has gradually been applied to forensic practice, providing objective evidence for health conditions before death, disease pathophysiological processes and forensic diagnosis of postmortem interval and cause of death. It is of great significance to understand the change patterns of postmortem biochemical indicators and their applications in forensic medicine. This article reviews the research progress of postmortem biochemistry and its application in forensic medicine, it summarizes the existing problems of postmortem biochemistry analysis in forensic medicine of China and discusses the application prospect of postmortem biochemistry analysis in forensic medicine. This review is expected to provide references for forensic practitioners.

Melatonin protects against excessive autophagy-induced mitochondrial and ovarian reserve function deficiency though ERK signaling pathway in Chinese hamster ovary (CHO) cells

Excessive autophagy-induced follicular atresia of ovarian granulosa cells might be one of the pathogenesis of Premature Ovarian Insufficiency (POI), and melatonin (MT) exerted many beneficial effects on mitochondria. However, there was little report regarding the beneficial effects of MT on excessive autophagy-induced mitochondrial and ovarian reserve function deficiency, and the mechanisms have not been clearly identified. Autophagy played a protective role in cells survival, however, high level of autophagy could lead to cell death. In this report, firstly, Chinese hamster ovary cell damage model stably expressing EGFP-LC3 was established. Next, we systematically investigated the protective effects of MT on mitochondrial and ovarian reserve function and molecular mechanisms using this cell damage model. Our results revealed that 10^-9 M MT not only protected against the decline of anti-mullerian hormone (AMH) expression induced by excessive autophagy, but also rescued excessive autophagy-induced impairment of mitochondrial expression and mitochondrial membrane potential. Furthermore, MT protected against excessive autophagy-induced decrease of nucleus-encoded proteins including SDHA and mitofilin, and mitochondrial dynamic-related proteins including OPA1, MFN2, and DRP1. MT also decreased mitochondrial oxidative stress, increased antioxidant enzyme superoxide dismutase 2 (SOD2) expression and ameliorated the G2/M cell cycle arrest induced by excessive autophagy. Finally, MT inhibited excessive autophagy-induced activation of extracellular signal regulated kinase (ERK) signaling pathway. In conclusion, our study showed that MT rescued impairment of mitochondrial and ovarian reserve function, and production of mitochondrial ROS and cell cycle arrest induced by excessive autophagy through down-regulated ERK pathway, implying the potential therapeutic drug target for POI.

A combination of genome-wide association study and selection signature analysis dissects the genetic architecture underlying bone traits in chickens

The bones of chicken play an important role in supporting and protecting the body. The growth and development of bones have a substantial influence on the health and production performance in chickens. However, genetic architecture underlying chicken bone traits is not well understood. The objectives of this study are to dissect the genetic basis of bone traits in chickens and to identify valuable genes and genetic markers for chicken breeding. We performed a combination of genome-wide association study (GWAS) and selection signature analysis (fixation index values and nucleotide diversity ratios) in an F₂ crossbred experimental population with different genetic backgrounds (broiler × layer) to identify candidate genes and significant variants related to femur, shank, keel length, chest width, metatarsal claw weight, metatarsal length, and metatarsal circumference. A total of 545 individuals were genotyped based on the whole genome re-sequencing method (26 F₀ individuals were re-sequenced at 10 × coverage; 519 F₂ individuals were re-sequenced at 3 × coverage). A total of 2 028 112 single-nucleotide polymorphisms (SNPs) remained to carry out analysis after quality control and imputation. The integration of GWAS and selection signature analysis indicated that all significant SNPs responsible for bone traits were mainly localized on chicken chromosomes 1, 4, and 27. Finally, we identified 21 positional candidate genes that might regulate chicken bone growth and development, including LRCH1, RB1, FNDC3A, MLNR, CAB39L, FOXO1, LHFP, TRPC4, POSTN, SMAD9, RBPJ, PPARGC1A, SLIT2, NCAPG, NKX3-2, CPZ, SPOP, NGFR, SOST, ZNF652, and HOXB3. Additionally, an array of uncharacterized genes was identified. The findings provide an in-depth understanding of the genetic architecture of chicken bone traits and offer a molecular basis for applying genomics in practical chicken breeding.

Stability of IgE in Postmortem Plasma and Hemolyzed Samples

Abstract

Objective To investigate the stability of IgE in postmortem plasma and hemolyzed samples under different storage conditions and freezing-thawing. Methods Thirty nine cardiac blood samples were collected from non-frozen corpses with the postmortem interval of less than 48 hours, including 20 plasma samples and 19 hemolyzed samples taken from whole blood. The samples were stored at -20 ℃, 4 ℃ and 25 ℃ for 28 d and at -80 ℃ for 1 year to evaluate the stability of IgE under different storage conditions. Repeated freezing-thawing treatment was conducted for 5 times to explore the stability of IgE in postmortem plasma and hemolyzed samples. IgE concentration in plasma and hemolyzed samples was detected by electroluminescence before and after treatment. Results The degradation rates of IgE in plasma samples under the three storage conditions, -20 ℃, 4 ℃ and 25 ℃ were close. After 28 d, the mean value was about 15%, the degradation speed of IgE in hemolyzed samples was faster than that of plasma under the same condition （P<0.05） and the degradation rate was faster than other two conditions under 25 ℃ （P<0.05）. The differences in the concentration of plasma samples after freezing at -80 ℃ for 1 year and that before freezing had no statistical significance （ P>0.05）, while the concentration of hemolyzed samples was degraded after freezing at -80 ℃ for 1 year （P<0.05）. The differences between the detection results of plasma and hemolyzed samples after repeated freezing-thawing for 5 times and that before freezing-thawing showed no statistical significance （ P>0.05）. Conclusion IgE has good freezing-thawing stability in postmortem plasma and hemolyzed samples. Stability of IgE is better in postmortem plasma samples than hemolyzed samples, thus it is recommended to separate plasma from postmortem blood samples as soon as possible in forensic practice.

Application of Hollow Fiber Ultrafiltration Technology in the Detection of Total IgE of Hemolytic Blood after Death

Abstract

Objective To investigate the treatment effect of hollow fiber ultrafiltration technology on hemolytic samples and the differences between IgE concentration and serum concentration before hemolysis in ultrafiltrate. Methods The 33 postmortem blood samples of non-frozen corpses within 72 hours after death were collected, 4 mL blood was taken from each case, among which 1 mL was centrifuged to get serum, and the remaining 3 mL blood was frozen-thawed 3-5 times to cause complete hemolysis. The 2 mL hemolytic samples were processed by hollow fiber ultrafiltration to obtain ultrafiltrate. The hemoglobin concentration in serum, complete hemolytic sample and ultrafiltrate was determined by Van-Zij solution-cyanated methemoglobin assay method, and the total IgE in serum and ultrafiltrate was determined by electrochemical luminescence method. Results The hemoglobin concentration in ultrafiltrate was significantly lower than that in complete hemolytic samples （P<0.05）. There was a good correlation between the total IgE detection values of ultrafiltrate and serum （r=0.984）. The difference between the serum and the value of IgE in ultrafiltrate after correction had no statistical significance, and the differences between the two in positive rates had no statistical significance （P>0.05）. Conclusion Ultrafiltration technology has a good treatment effect on complete hemolytic samples, and the correction value of ultrafiltrate detection is close to the serum level before hemolysis, and therefore, it can be applied to the detection of total IgE of frozen corpse hemolytic samples.

Research Progress and Forensic Identification of Alcoholic Cardiomyopathy

Abstract

With the rapid development of the social economy in China, the incidence of diseases caused by excessive drinking is gradually increasing as well. Alcoholic cardiomyopathy refers to long-term high intake of ethanol, and has typical dilated cardiomyopathy characteristics, such as, hemodynamic changes, symptoms, signs, and morphological features. It is a kind of cardiomyopathy that excludes other causes of dilated cardiomyopathy. Due to the lack of specific pathological changes, the forensic pathological identification of alcoholic cardiomyopathy can only be based on the patient's medical history and by ruling out other causes of cardiomyopathy. This paper reviews the pathogenesis and forensic identification of alcoholic cardiomyopathy in order to provide reference for forensic pathologists and clinicians.

Statistical Analysis of the Heart and Lung Mass in Forensic Anatomical Cases and Its Forensic Significance

Abstract

Objective To investigate the differences of heart mass and lung mass in forensic autopsy cases and to explore their application value in forensic identification. Methods The data from 1 614 autopsy cases accepted by center of Medico-legal Investigation of China Medical University between 2007 to 2016 were collected. The correlation of heart and lung mass with age, height, body weight, and body mass index （BMI）, as well as differences in different causes of death were analyzed by GraphPad Prism 6.0 software. Results The heart mass and lung mass of males were higher than those of females （P<0.05）. The heart mass of males and females was positively correlated with age, height, body weight and body mass index （BMI） （P<0.05）. The heart mass of patients dying from sudden cardiac death （SCD） was significantly higher than those dying from other causes of death. The lung mass of patients dying from drowning and delayed treatment was higher than those dying from other causes of death （P<0.05）. Conclusion In forensic practice, measurement of the heart mass and lung mass has certain significance for differential diagnosis and diagnosis of different causes of death.

Effect of Corpse Cryopreservation on Forensic Pathological Identification

Because cryopreservation can effectively slow down the putrefaction and prolong the preservation time of corpses, it has become the main way of corpse preservation in China. However, it may cause a certain degree of non-specific effects on the corpses and thus interfere with forensic pathological identification. This paper summarizes relevant problems reported in domestic and foreign literature reports and practical identification, and analyzes the effects of cryopreservation on corpses from aspects of anatomical findings, histomorphology, postmortem biochemistry, and postmortem imaging, therefore to provide Chinese forensic workers assistance on problems in their practice of forensic pathology.

Forensic Pathological Identification and Antidiastole of Commotio Cordis

Commotio cordis （CC） is the acute death caused by the cardiac rhythm disorder after a sudden blunt external force to the precordium of a healthy person without previous heart disease. As one type of violent heart damage, CC is rare with relatively small external force and sudden death, therefore causing disputes. This paper reviews the epidemiology, mechanisms and the key points in forensic identification of CC, discusses the identification and antidiastole of CC, myocardial contusion, sudden cardiac death and death from inhibition, and provides assistance to forensic pathologists to identify such causes of death.

[Expression of Brain Natriuretic Peptide in Myocardial Tissue of Sudden Cardiac Death and Non-sudden Cardiac Death]

OBJECTIVES

To study the expression pattern of brain natriuretic peptide （BNP） in myocardial tissue from forensic routine cases and to explore its application value in the forensic determination of sudden cardiac death （SCD）.

METHODS

The data of 96 autopsy cases accepted by the center of Medico-legal Investigation of China Medical University between December 2008 to May 2014 were collected. There were 62 cases in SCD group cardiac and 34 cases in non-SCD group. The myocardial tissues were taken from left and right ventricular wall, respectively. The expressions of BNP protein and BNP mRNA in myocardial tissue were detected by HE staining, immunohistochemical staining, Western blotting and quantitative real-time reverse transcription-polymerase chain reaction （RT-qPCR）, etc.

RESULTS

The immunohistochemical staining of myocardial tissue showed diffusely positive staining in SCD group, and patchily or diffusely positive staining in non-SCD group with lighter degree. The result of Western blotting showed that the expression of BNP protein elevated in left ventricular wall of SCD group. The result of RT-qPCR showed a positive correlation between the BNP mRNA expressions in bilateral ventricular walls and the heart weight, bilateral lung weight, and N-terminal prohormone of brain natriuretic peptide （NT-proBNP） concentration. There were large differences between the BNP mRNA concentrations in SCD group and non-SCD group, and the former was statistically higher （P<0.05）.

CONCLUSIONS

The expressions of BNP protein and BNP mRNA in myocardial tissue are related to the causes of death. Combined with pathological changes, the expressions of BNP protein and BNP mRNA in myocardial tissue have certainly practical significance for the determination of SCD and the analysis of the death mechanism in the cases related to forensic pathology.

[The Changes of HIF-1α and VEGF-A in Myocardial Tissue of Rats with Arrhythmias]

OBJECTIVES

To observe the expression changes of hypoxia inducible factor-1α（HIF-1α） and vascular endothelial growth factor-A （VEGF-A） in rats with arrhythmias, and to explore the differences of the expression pattern in the two indicators of acute myocardial ischemia caused by arrhythmias and coronary insufficiency.

METHODS

The arrhythmia was induced by CaCl₂, and the expression changes of HIF-1α and VEGF-A were detected by immunohistochemistry, Western blotting and real-time PCR within 6 h after the arrhythmia in rats.

RESULTS

The expression of HIF-1α and VEGF-A showed diffuse in the myocardial tissue of rats died from arrhythmias. Both of them increased in the early arrhythmia, then decreased. Extensive myocardial ischemia happened at the beginning of arrhythmia occurrence and its range didn't expand with time.

CONCLUSIONS

The expressions of HIF-1α and VEGF-A in myocardium of the rats with arrhythmia can provide evidence for the differential diagnosis of acute myocardial ischemia caused by fatal arrhythmia and coronary insufficiency.

[Prognostic factors of patients with T2N0M0 upper tract urothelial carcinoma: a single-center retrospective study of 235 patients]

OBJECTIVE

To evaluate the impacts of the prognostic factors of T2N0M0 upper tract urothelial carcinoma (UTUC) for Chinese patients.

METHODS

A retrospective study was conducted including 235 patients who were diagnosed with T2N0M0 UTUC in our hospital and received radical nephroureterectomy (RNU) or partial ureterectomy during January 2000 and December 2013. The 3 and 5-year cancer-specific survival rates and bladder recurrence-free survival rates of all the patients were valued using Kaplan-Meier method, and the survival curves with statistical significance between the two were compared using the Log-rank test. Variables with significant differences in the univariate analysis were subjected to the multivariate analysis by Cox regression model.

RESULTS

A total of 235 patients were included in this study, including 95 (40.4%) male patients and 140 (59.6%) female patients. The mean age was 66.73±10.49 years.The median follow-up time was 53 (rang: 3-142) months, and during the follow-up, 74 (31.5%) patients died of UTUC after a median of 35 months,and 96 (40.9%) patients developed intravesical recurrence after a median of 19.5 months. The 3 and 5-year cancer-specific survival rates of all the patients were 89.1% and 85.9%, respectively; the bladder recurrence-free survival rates were 85.5% and 80.2%, respectively. The independent prognostic factors of cancer-specific mortality were tumor age elder than 55 years (HR=3.138, 95%CI: 1.348-7.306, P=0.008) and diameter larger than 5 cm (HR=3.320, 95%CI: 1.882-5.857, P<0.001). The independent prognostic factors of bladder recurrence-free survival were ureter tumor (HR=1.757, 95%CI: 1.159-2.664, P=0.008) and lower tumor grade (HR=1.760, 95% CI: 1.151-2.692, P=0.009).

CONCLUSION

T2N0M0 UTUC has a better cancer-specific survival. The intravesical recurrence was equivalent to non-muscle invasive UTUC but earlier. The tumor diameter larger than 5 cm and the patient age elder than 55 years were independently associated with cancer-specific mortality; the primary tumor located in ureter and lower tumor grade were more likely to develop intravesical recurrence.

Differential expression of B-type natriuretic peptide between left and right ventricles, with particular regard to sudden cardiac death

The aim of the present study was to investigate the differential expression of B-type natriuretic peptide (BNP) between the left and right ventricle (RV) in sudden cardiac death (SCD). A total of 26 forensic autopsy cases of sudden death (survival time <30 min, postmortem interval <48 h or frozen within 6 h following death) in the present institute were examined. The cases consisted of acute ischemic heart disease (AIHD, n=15) with/without apparent myocardial necrosis as a sign of infarction (acute myocardial infarction, n=6; ischemic heart disease, IHD, n=9), and arrhythmogenic right ventricular cardiomyopathy (ARVC/D, n=5), in addition to traffic accidents and high falls without any pre existing heart disease as control (C, total n=6). BNP was investigated in all cases by the colloidal gold method, hematoxylin-eosin staining, immunohistochemistry (IHC) and the molecular pathological method. The IHC results demonstrated that a positive BNP immunostaining was detected in all groups; however, there was no difference between different causes of death. Pericardial N-terminal (NT)-proBNP concentration was significantly increased in deaths resulting from AIHD and ARVC/D compared with control group. The relative quantification of BNP mRNA demonstrated that relative expression levels of BNP mRNA were significantly increased in the left ventricle (LV) in the AIHD group, and in the RV of the ARVC/D group. The relative quantification difference and ratio of BNP mRNA between LV and RV demonstrated a significantly greater value in the AIHD group compared with control group. BNP mRNA in myocardium and NT-proBNP concentration in pericardial fluid were elevated in SCD patients, and left ventricular dysfunction predominated in AIHD patients, whereas right ventricular dysfunction predominated in ARVC/D patients. The results of the present study suggest the possible use of molecular pathology of BNP for the determination of terminal cardiac function in SCD and analysis of its fatal mechanism in forensic practice.

The Expression of B-Type Natriuretic Peptide After CaCl2-Induced Arrhythmias in Rats

To investigate the patterns of B-type natriuretic peptide (BNP) expression after arrhythmia, BNP was assessed at different time points (0 minute, 10 minutes, 30 minutes, 1 hour, 3 hours, and 6 hours) in CaCl2-induced arrhythmia in rats through various methods such as immunohistochemistry, Western blotting, quantitative real-time polymerase chain reaction, and enzyme-linked immunosorbent assay. Immunohistochemistry results showed that the expression of BNP in the endocardium was higher than that in the epicardium in rats undergoing sustained arrhythmias. The BNP-to-GAPDH (glyceraldehyde-3-phosphate dehydrogenase) ratios determined by Western blotting analysis revealed no change at 0 minute but increased at 10 minutes and reached the first peak (0.48 [0.03]) at 30 minutes. After a brief decline, the second peak was observed at 6 hours (0.54 [0.03]). Similar patterns of BNP messenger RNA expression were also observed by quantitative real-time polymerase chain reaction. The plasma BNP concentrations did not change after initial bouts of cardiac arrhythmias but significantly increased 30 minutes after CaCl2 injections. The results demonstrate that arrhythmia causes an elevation of BNP in the myocardium and blood, and BNP messenger RNA increases in initial arrhythmia while its protein in myocardium and plasma does not; however, both of them were elevated after sustained arrhythmia. Such an elevated BNP expression, which is directly related to the severity and duration of the arrhythmias, may suggest the existence of fatal arrhythmia in sudden cardiac death.

Gap maximum of graphene nanoflakes: a first-principles study combined with the Monte Carlo tree search method

The energy gap of graphene nanoflakes is important for their potential application in nano-devices; however, it is still a challenge to perform a systemic search of systems with large gaps due to the presence of numerous candidates.

Expression analysis of bone morphogenetic protein 4 between fat and lean birds in adipose tissue and serum

The objectives of the present study were to characterize the tissue expression of chicken (Gallus gallus) bone morphogenetic protein 4 (BMP4) and compare differences in its expression in abdominal fat tissue and serum between fat and lean birds and to determine a potential relationship between the expression of BMP4 and abdominal fat tissue growth and development. The results showed that chicken BMP4 messenger RNA (mRNA) and protein were expressed in various tissues, and the expression levels of BMP4 transcript and protein were relatively higher in adipose tissues. In addition, the mRNA and protein expression levels of BMP4 in abdominal fat tissue of fat males were lower than those of lean males at 1, 2, 5, and 7 wk of age (P < 0.05). Furthermore, the serum BMP4 content of fat males was lower than that of lean males at 7 wk of age (P < 0.05). BMP4 mRNA expression levels were significantly higher in preadipocytes than those in mature adipocytes (P < 0.05), and the expression level decreased during differentiation in vitro (P < 0.05). These results suggested that chicken BMP4 might affect abdominal fat deposition through differences in its expression level. The results of this study will provide basic molecular information for studying the role of BMP4 in the regulation of adipogenesis in avian species.

Estimating the genetic parameters for liver fat traits in broiler lines divergently selected for abdominal fat

Intensive selection of broilers for improved growth rate is known to exert a negative effect on broiler health, such as an increase in body fat (and its related diseases). Excessive fat deposition in the liver can cause fatty liver hemorrhagic syndrome (FLHS); in addition, traits associated with liver fat have also been associated with FLHS. This study explored the genetic relationships among liver fat-related traits. Data was collected from 462 birds derived from 16th generation Northeast Agricultural University broiler lines divergently selected for abdominal fat content. The body weight at 7 weeks of age (BW7), abdominal fat weight (AFW), abdominal fat percentage, liver fat percentage (LFP), liver weight, and liver percentage were measured. The heritability of these traits and the phenotypic and genetic correlations were estimated, using the restricted maximum likelihood (REML) and Gibbs sampling (GS) methods. The REML and GS methods yielded similar heritability estimates for LFP (0.36 and 0.37, respectively). BW7 showed a high positive genetic correlation with AFW (rA(REML) = 0.74 and rA(GS) = 0.80), and a moderate positive genetic correlation with LFP (rA(REML) = 0.27 and rA(GS) = 0.39). Positive genetic correlations were also observed between AFW and LFP (rA(REML) = 0.35 and rA(GS) = 0.36). These results suggested that selection for growth may increase the AFW and LFP in broilers. LFP is directly related to FLHS; therefore, selection for broiler growth rate may increase the incidence of FLHS.

Enhanced anaerobic digestion of waste activated sludge of low organic content in a novel digester

A novel digester, termed an internal circulation anaerobic digester (ICAD), was developed to intensify sludge digestion. It consists of reaction zone, settling zone, thickening zone, riser and downcomer. Internal circulation in the digester is intensified by backflow biogas. The mesophilic ICAD treating thermal pretreated waste activated sludge with volatile suspended solids (VSS)/suspended solids (SS) of 0.45-0.49 was conducted in this study to reduce and stabilize the low organic content sludge. The results showed that the VSS removal rate and biogas rate reached 46.0% and 0.72 m(3)/kg VSS(fed) at hydraulic retention time (HRT) of 15 days. VSS/SS and soluble chemical oxygen demand (SCOD) of the effluent sludge ranged from 0.39 to 0.41 and 274 mg/L to 473 mg/L, respectively, under various HRTs from 10 to 27 days. The degradation ability of ICAD derived from the improved mass transfer by internal circulation and long solid retention time at short HRT is compared with continuous stirred tank reactor.

[Biochemical indicators of anaphylactic shock and the application in forensic medicine]

Fatal anaphylactic shock is common in forensic practice. However, it is difficult to diagnose for lacking specific pathological and morphologic changes in forensic autopsy. The application of some biochemical indicators is of great significance. This paper reviews the biological characteristics of some biochemical indicators and detection methods. The forensic application, problems and prospects of these indicators are also introduced in details. The stable biochemical indicators, IgE, tryptase and chymase, show great potential and advantages in the identification of fatal anaphylactic shock in forensic medicine.

[Expression of BNP in rat myocardial tissue after acute cardiac dysfunction]

OBJECTIVE

To investigate the expression of brain natriuretic peptide (BNP) in rat myocardial tissue after acute cardiac dysfunction and to explore the role of BNP in diagnosis of cardiac dysfunction in forensic practice.

METHODS

Rat models of acute cardiac dysfunction were established. The expression of BNP protein and BNP mRNA in myocardial tissue after cardiac dysfunction were detected by immunohistochemistry, Western blotting and real-time RT-PCR.

RESULTS

The extent of positive staining of BNP increased over the time course during cardiac dysfunction. The expression of BNP showed mild positive in cardiomyocytes from 1 h to 2 h. From 4 h to 6 h, the expression was moderate positive. From 10 h to 12 h, the BNP showed a strongest positive expression. The expression of BNP presented a significant raise with the increasing time of cardiac dysfunction by Western blotting and real-time RT-PCR. The expression of BNP mRNA increased significantly 1 h after cardiac dysfunction.

CONCLUSION

Investigating the expression of BNP protein and BNP mRNA in myocardial tissue may provide a new approach to evaluate the cardiac function for forensic pathologists.

[Mechanism of methamphetamine intoxication and its medical identification]

Methamphetamine (MA) is a representative drug of amphetamine-type stimulants for central nervous system and has become one of the most dangerous drugs in the world recently. The present article reviews the pharmacological effects, distribution, metabolism, intoxication mechanism, the effects of MA on cardiovascular and central nervous systems of MA, and the current situation of forensic investigation on MA.

Association of Spot14α Gene Polymorphisms with Body Weight in the Chicken

In mammals, thyroid hormone responsive Spot14 (THRSP) is a small acidic protein that responds to thyroid hormone stimulation and, therefore, is thought to play a role in growth. The current study was designed to investigate the associations of Spot14alpha gene polymorphisms on chicken growth and body composition traits. The Northeast Agricultural University Resource Population (NEAURP) was used in the present study. The NEAURP was established by crossing broiler sires, derived from Northeast Agricultural University broiler lines divergently selected for abdominal fat content, with Baier layer dams, a local Chinese breed. The F(1) birds were intercrossed to produce the F(2) population. Body weight and body composition traits were measured in the F(2) population. Polymorphisms of the gene were detected between parental lines by DNA sequencing. Primers were designed according to the chicken Spot14alpha gene (AY568628). The PCR-RFLP and PCR-length polymorphisms methods were then developed to genotype polymorphisms in the NEAURP. The A213C and 9 bp insertion-deletion of the Spot14alpha gene in the F(2) population was found to be associated with BW, which implied that Spot14alpha gene or a tightly linked gene had an important effect on growth in the chicken.

[Role of cardiac renin-angiotensin system in swimming induced physiological myocardial hypertrophy]

To determine the contribution of cardiac renin-angiotensin system (RAS) to the physiological myocardial hypertrophy induced by swimming training and the relationship between locally produced and circulating RAS, both ventricular and plasma angiotensin (Ang) I and II contents, ventricular angiotensin converting enzyme (ACE) and plasma renin activity (PRA) were detected by means of radioimmunoassay and biochemical method. It was shown that after 5 weeks of swimming, the ventricular wet weight to body weight ratio (V/Bwt) and Ang II in both left and right ventricles and ACE activity increased markedly as compared with the controls (P < 0.05). Furthermore, significantly positive correlation was found between the ventricular Ang II and V/Bwt (r = 0.7721, P < 0.001), while the plasma Ang I and II and PRA remained at the control level. No correlation was found between plasma Ang II and V/Bwt. These above findings suggest that cardiac RAS may play an important role in physiological myocardial hypertrophy and to a large extent is in dependent on circulating RAS.