[Pollution characteristics and health risk assessment of heavy metals in PM(2.5) in Lanzhou]

Objective: To understand the pollution characteristics and assess the pollution health risks of heavy metals in atmospheric PM(2.5) in Lanzhou. Methods: According to the regional characteristics of air pollution and industrial distribution characteristics in Lanzhou, atmospheric PM(2.5) was sampled monthly in Chengguan and Xigu Districts from January, 2015 to December, 2016. Detected the concentration of PM(2.5) and 12 kinds of elements (Sb, Al, As, Be, Cd, Cr, Hg, Pb, Mn, Ni, Se and Tl) by weighing method and inductively coupled plasma mass spectrometry. Enrichment factor and geo-accumulation index were used to describe the pollution characteristics, while health risk assessment was conducted using the recommended United States Environmental Protection Agency (USA EPA) model. The health risks of non-carcinogens were evaluated by non-cancer hazard quotient (HQ), the non-carcinogenic risk was considered to be negligible when HQ<1, HQ>1 meant a health risk. With a single contaminant cancer Risk value to evaluate the health risks of carcinogens, when the Risk value between 10(-6) to10(-4) as an acceptable level. Results: The daily average concentrations of PM(2.5) was 83.0 μg/m(3), 77.0 μg/m(3) in Chengguan and Xigu Districts, respectively, during the sampling periods, and the concentration of PM(2.5) in winter/spring was higher than summer/fall in both districts. The concentration of Al in PM(2.5) was the highest and other elements in descending order: Pb, Mn, As, Sb/Cd, Tl in both districts. Enrichment factor results showed that Al and Mn were mainly affected by natural factors, the rest of five elements were all typical man-made pollution elements and according to geo-accumulation index pollution level of Cd was the strongest in the winter. The results of health risk assessment showed that Mn had the highest non-cancer risks (HQ>1) and affected the health of the children seriously. HQ reached up to 2.44 and 1.79 in Chengguan and Xigu Districts, respectively. Pb, As, Sb, Cd had slight health impact (HQ<1), could be negligible. The cancer risks range of As, Cr were 6.33×10(-6) to 6.46×10(-5) between the acceptable level of risk (10(-6) to 10(-4)), which indicated that As and Cd had potential cancer-risks. Conclusions: The pollution level of atmospheric PM(2.5) and the heavy metals in it was still grim;the non-cancer risks caused by multiple metals on children deserved attention. Although the cancer risks of As and Cd were between the acceptable level of risk, the potential cancer risk still shall not be ignored.

[Preliminary analysis of the effects of individualized sound therapy on chronic subjective tinnitus]

Objective:To explore the effect of individualized multi-compound sound therapy on chronic subjective tinnitus and the relationship between tinnitus frequency," notch " hearing loss and the treatment effect of sound therapy.Method: Seventy-eight cases of chronic subjective tinnitus with the pure tone test threshold (PTA)in normal range (≤25 dB HL)were enrolled in this study. Their hearing threshold were re-evaluated using the precise pure-tone audiogram (P-PTA).Tinnitus was evaluated on pitch and loudness matching, and the effectiveness of tinnitus was measured using Tinnitus Handicap Inventory (THI) before they received the individualized customized multi-compound sound therapy for 3 months. THI were re-evaluated on the 30th day and 90th day after treatment.Result: ①The averaged THI score of these patients before the sound treatment was 24.62±15.65 (n=78). The score dropped significantly to 15.82±13.02 and 13.62 ±10.98 on the 30th day and 90th day after treatment, respectively (P<0.01). ②Patient' s gender, age, and the side of tinnitus has no effect on the sound treatment of tinnitus. ③Of these 78 tinnitus patients, 31 patients who showed "notch " hearing loss and 47 patients without "notch " hearing loss in the P-PTA. The averaged THI score between the patients with and without "notch " showed no statistical difference after the treatment (P>0.05).These data suggested that "notch " hearing loss in P-PTA has no effect on the sound therapy.④Of 31 tinnitus patients with "notch " hearing loss, the tinnitus frequency of 22 cases was at the "notch " hearing loss and that of 9 cases was not at the "notch " hearing loss. Sound treatment showed significant between the former and the latter(P<0.05). After 30 days of treatment, tinnitus frequency of four patients whose tinnitus was not at the notch hearing loss drifted to the "notch " hearing loss frequency. Conclusion: Customized multi-compound sound therapy can reduce the THI score of chronic subjective tinnitus patients.The treatment reduced patient's anxiety and improved their quality of life.Sound treatment showed a better improvement in the patients whose tinnitus frequency was located at their notch hearing loss.

A case report of perineal sparganosis mansoni from an endemic region

Sparganosis mansoni is a parasitic disease caused by the larva of Spirometra mansoni, which occurs worldwide, especially in Asian countries. In recent years, there have been cases of sparganosis reported in Guizhou province in southwest China. In this report, a case of sparganosis mansoni with a painful mass in perineal region is presented. The patient is a 49-year-old Chinese woman, she did not have a history of eating raw frogs or snakes. But she drank unboiled water from rivers and streams. Physical examination showed her vital signs were stable and blood routine examination was also regular. After surgery to remove the mass, a worm was removed from the foreign matter, which measured about 10 cm in length and 2 mm in diameter, that was identified as S. mansoni. One week after the operation, her symptoms changed significantly. To our knowledge, this is the first case of perineal sparganosis mansoni in Guizhou. Surgical removal is effective for the treatment of perineal sparganosis, followed by a course of therapy.

Characterization of transcriptional complexity during pre-implantation development of the yak (Bos grunniens) using RNA-Seq

The objective of this study was to investigate the mechanism that regulates pre-implantation development of the yak (Bos grunniens). We determined the transcriptomes of in vitro-produced yak embryos at two-cell, four-cell, eight-cell stages, and morula and blastocyst using the Illumina RNA-seq for the first time. We obtained 47.36-50.86 million clean reads for each stage, of which, 85.65%-90.02% reads were covered in the reference genome. A total of 17,368 genes were expressed during the two-cell stage to blastocyst of the yak, of which 7,236 genes were co-expressed at all stages, whereas 10,132 genes were stage-specific expression. Transcripts from 9,827 to 14,893 different genes were detected in various developmental stages. When |log₂ ratio| ≥ 1 and q-value <0.05 were set as thresholds for identifying differentially expressed genes (DEGs), we detected a total of 6,922-10,555 DEGs between any two consecutive stages. The GO distributions of these DEGs were classified into three categories: biological processes (23 terms), cellular components (22 terms) and molecular functions (22 terms). Pathway analysis revealed 310 pathways of the DEGs that were operative in early pre-implantation yak development, of which 32 were the significantly enriched pathways. In conclusion, this is the first report to investigate the mechanism that regulates yak embryonic development using high-throughput sequencing, which provides a comprehensive framework of transcriptome landscapes of yak pre-implantation embryos.

[Correlation between Genetic Variants and Polymorphism of Caveolin and Sudden Unexplained Death]

OBJECTIVES

To explore the genetic variation sites of caveolin （CAV） and their correlation with sudden unexplained death （SUD）.

METHODS

The blood samples were collected from SUD group （71 cases）, coronary artery disease （CAD） group （62 cases） and control group （60 cases）, respectively. The genome DNA were extracted and sequencing was performed directly by amplifying gene coding region and exon-intron splicing region of CAV1 and CAV3 using PCR. The type of heritable variation of CVA was confirmed and statistical analysis was performed.

RESULTS

A total of 4 variation sites that maybe significative were identified in SUD group, and two were newfound which were CAV1： c.45C>T （T15T） and CAV1：c.512G>A （R171H）, and two were SNP loci which were CAV1：c.246C>T （rs35242077） and CAV3：c.99C>T （rs1008642） and had significant difference （P<0.05） in allele and genotype frequencies between SUD and control groups. Forementioned variation sites were not found in CAD group.

CONCLUSIONS

The variants of CAV1 and CAV3 may be correlated with a part of SUD group.

Epidemiology and molecular characterization of Porcine teschovirus in Hunan, China

Porcine teschoviruses (PTVs) have been shown to be widely distributed in pig populations. In this study, 261 faecal and 91 intestinal content samples collected from pigs at 29 farms in Hunan, China, were tested for the presence of PTV by reverse transcription-polymerase chain reaction (RT-PCR). An overall PTV-positivity rate of 19.03% was detected by RT-PCR, and a high PTV infection rate was circulating in asymptomatic fattening and nursery pigs. In total, 40 PTV isolates (PTV-HuNs) were obtained. Alignment of their coding sequences with those of other known PTVs revealed that the genomic sequence of the polyprotein contains 6,606-6,621 nucleotides, encoding a 2,202-2,207-amino acid sequence. Phylogenetic analyses based on the VP1 gene and capsid protein gene exhibited 13 main lineages corresponding to PTV serotypes 1-13, and seven PTV serotypes (PTV 2-6, 9, and 11) were identified in the isolates obtained in our study; this is the first report of PTV 5, 9 and 11 in China. Recombination analysis among the PTV-HuNs indicated that nine recombination events have occurred, including both inter- and intraserotype events. In addition, results demonstrated that only limited positive selection is acting on the global population of PTV isolates, and purifying selection is predominant. In conclusion, this study revealed a high infection rate of PTVs circulating in asymptomatic fattening and nursery pigs. The 40 PTV-HuNs showed high genetic diversity, and genetic analysis of all available PTV sequences revealed that strong purifying selection and recombination play important roles in the genetic diversity and evolution of the virus.

[Research Progress of the Correlation between Caveolin and Unexpected Sudden Cardiac Death]

Due to the negative autopsy and without cardiac structural abnormalities, unexpected sudden cardiac death （USCD） is always a tough issue for forensic pathological expertise. USCD may be associated with parts of fatal arrhythmic diseases. These arrhythmic diseases may be caused by disorders of cardiac ion channels or channel-related proteins. Caveolin can combine with multiple myocardial ion channel proteins through its scaffolding regions and plays an important role in maintaining the depolarization and repolarization of cardiac action potential. When the structure and function of caveolin are affected by gene mutations or abnormal protein expression, the functions of the regulated ion channels are correspondingly impaired, which leads to the occurrence of multiple channelopathies, arrhythmia or even sudden cardiac death. It is important to study the effects of caveolin on the functions of ion channels for exploring the mechanisms of malignant arrhythmia and sudden cardiac death.

[Forensic Application of Objective Assessment on Visual Acuity by ERP]

OBJECTIVES

To explore the composition characteristic of event related potential （ERP） in different visual acuity levels, and to provide theoretical basis for the objective assessment of visual acuity.

METHODS

Monocular stimulus was performed on 16 selected subjects. The subjects were required to look straight at the screen ahead and count the amount of stimuli from different directions. The pictures of optotype stimulus which corresponding to three different visual acuity levels were showed in the center of the screen. The ERP results were recorded separately.

RESULTS

（1） The P₁ amplitudes of match stimuli recorded under the supra-threshold visual acuity level were higher than that of match stimuli recorded under the threshold and sub-threshold visual acuity levels. There was no significant difference between the P₁ amplitudes of match stimuli recorded under the threshold and sub-threshold visual acuity levels. The tendency of conflict stimuli was similar to that of match stimuli under three visual acuity levels. （2） In the 340-500 ms post-stimulus range, P₃₀₀ component was found under supra-threshold and threshold visual acuity levels; no P₃₀₀ component was found in corresponding time window under sub-threshold visual acuity. The differences of P₃₀₀ amplitudes among three visual acuity levels were statistically significant. The amplitudes from high to low were the supra-threshold, threshold and sub-threshold visual acuity levels.

CONCLUSIONS

ERP can be a potential new method for the objective assessment of visual acuity in forensic medicine.

[Effect of Different Attentional Conditions on ERP Detection of Visual Acuity]

OBJECTIVES

To study the effect of different attentional conditions on the event-related potential （ERP） components generated by the visual information stimuli related to visual acuity, and provide a theoretical reference for clinical forensic visual objective evaluation.

METHODS

With visual acuity optotypes as normal form of visual information stimuli, 15 volunteers as study subjects were supposed to account the visual acuity optotypes under the attentional condition of visual stimuli. Furthermore, the subjects were required to listen to the storytelling carefully under the non-attentional condition of visual stimuli, and after the examination, they needed to answer the story-related questions. All the EEG results of two different attentional conditions from the subjects were recorded by 32 channel ERP system.

RESULTS

Under two attentional conditions, P₁ and P₃₀₀ components were evoked by the visual acuity optotypes on supra-threshold and threshold visual acuity levels, while only P₁ component were evoked by the visual acuity optotypes on sub-threshold levels. In the ERP waveforms evoked by the visual acuity optotypes on supra-threshold, P₁ and P₃₀₀ amplitudes under attentional condition were larger than that under non-attentional condition.

CONCLUSIONS

Attentional conditions can influence the detection of visual acuity. P₃₀₀ component can be used to distinguish the visual acuity levels with supra-threshold and sub-threshold under non-attentional condition.

[Intracranial mixed germ cell tumor]

Objective: To study intracranial mixed germ cell tumor diagnosis and reasonable treatment strategy. Methods: Clinical data of 17 patients with intracranial mixed germ cell tumor in Tsinghua university Yuquan hospital from October 2012 to October 2016 were retrospective analysed, including the characteristics of the general, the serum tumor markers of AFP, β-HCG, and CEA, imaging findings, pathological results, treatment methods and prognosis. Results: There were 10 cases of male, 7 cases of female. The average age was (11.1±5.2) years old. Nine cases were gross total resection of lesions and 8 cases were subtotal resection of lesions. Eight cases (47.1%) were without recurrence and had more than four courses of chemotherapy after surgery, of which, 7 cases belonged to the gross total resection, and 1 case belonged to the subtotal resection. Nine (52.9%) patients relapsed, including 2 cases of the gross total resection and 7 cases of the subtotal resection. Among them, 4 cases were given second operations and 6 cases obtained satisfactory therapeutic effect by chemotherapy combined radiotherapy. There were 12 of 17 patients with pathological types contain teratoma (including mature, immature or malignant teratoma) ingredients, accounting for 70.6%. The average follow-up time was (17.5±12.1) months, 4 cases (23.5%) patients died. Conclusion: The diagnosis of intracranial mixed germ cell tumors needs comprehensive consideration of tumor markers in serum or cerebrospinal fluid, chemotherapy and radiotherapy before operation and pathological results. The gross total resection helps to reduce the chances of tumor recurrence. Rational chemotherapy and radiotherapy is helpful to prognosis.

[Intracranial mixed germ cell tumor]

Objective: To study intracranial mixed germ cell tumor diagnosis and reasonable treatment strategy. Methods: Clinical data of 17 patients with intracranial mixed germ cell tumor in Tsinghua university Yuquan hospital from October 2012 to October 2016 were retrospective analysed, including the characteristics of the general, the serum tumor markers of AFP, β-HCG, and CEA, imaging findings, pathological results, treatment methods and prognosis. Results: There were 10 cases of male, 7 cases of female. The average age was (11.1±5.2) years old. Nine cases were gross total resection of lesions and 8 cases were subtotal resection of lesions. Eight cases (47.1%) were without recurrence and had more than four courses of chemotherapy after surgery, of which, 7 cases belonged to the gross total resection, and 1 case belonged to the subtotal resection. Nine (52.9%) patients relapsed, including 2 cases of the gross total resection and 7 cases of the subtotal resection. Among them, 4 cases were given second operations and 6 cases obtained satisfactory therapeutic effect by chemotherapy combined radiotherapy. There were 12 of 17 patients with pathological types contain teratoma (including mature, immature or malignant teratoma) ingredients, accounting for 70.6%. The average follow-up time was (17.5±12.1) months, 4 cases (23.5%) patients died. Conclusion: The diagnosis of intracranial mixed germ cell tumors needs comprehensive consideration of tumor markers in serum or cerebrospinal fluid, chemotherapy and radiotherapy before operation and pathological results. The gross total resection helps to reduce the chances of tumor recurrence. Rational chemotherapy and radiotherapy is helpful to prognosis.