Translating mesenchymal stem cell and their exosome research into GMP compliant advanced therapy products: Promises, problems and prospects

Mesenchymal stem cells (MSCs) are one of the few stem cell types used in clinical practice as therapeutic agents for immunomodulation and ischemic tissue repair, due to their unique paracrine capacity, multiple differentiation potential, active components in exosomes, and effective mitochondria donation. At present, MSCs derived from tissues such as bone marrow and umbilical cord are widely applied in preclinical and clinical studies. Nevertheless, there remain challenges to the maintenance of consistently good quality MSCs derived from different donors or tissues, directly impacting their application as advanced therapy products. In this review, we discuss the promises, problems, and prospects associated with translation of MSC research into a pharmaceutical product. We review the hurdles encountered in translation of MSCs and MSC-exosomes from the research bench to an advanced therapy product compliant with good manufacturing practice (GMP). These difficulties include how to set up GMP-compliant protocols, what factors affect raw material selection, cell expansion to product formulation, establishment of quality control (QC) parameters, and quality assurance to comply with GMP standards. To avoid human error and reduce the risk of contamination, an automatic, closed system that allows real-time monitoring of QC should be considered. We also highlight potential advantages of pluripotent stem cells as an alternative source for MSC and exosomes generation and manufacture.

[Contrast-enhanced ultrasound manifestations of IgG4 related autoimmune pancreatitis]

To analyze and summarize the contrast-enhanced ultrasound (CEUS) characteristics in patients with IgG4 related autoimmune pancreatitis (IgG4-AIP). A total of 54 patients (aged 26 to 76 years old) with IgG4-AIP were collected and retrospectively analyzed. The results demonstrated that there is a variety of enhanced performance on CEUS in patients with IgG4-AIP in the early stage, for some them, especially for those with mass-type pancreatitis, their sonographic appearance and the CEUS characteristics are similar when compared with the patients with pancreatic carcinoma, with varying degrees of low enhancement in the arterial phase, venous phase and delayed stage. Therefore, it is not advisable to make a differential diagnosis based on CEUS alone, and comprehensive evaluation is warranted.

Mitochondrial DNA Polymorphism in Zhejiang She Population Based on Next Generation Sequencing

Abstract

Objective To study the genetic polymorphism of whole mitochondrial DNA （mtDNA） genomes in She population in Zhejiang and to explore the maternal genetic structure of the She population. Methods Whole mtDNA genomes of 231 unrelated individuals from She population in Zhejiang Province were sequenced. The number of mutations and population genetics parameters such as, the haplotype diversity （HD）, discrimination power （DP）, and random match probabilities （RMP） were analyzed. The mtDNA haplogroups of Zhejiang She population were classified, and the maternal genetic relationships between She and nine other Chinese populations were estimated. Results In 231 Zhejiang She samples, 8 507 mutations （702 types） were observed and the samples were classified into 94 haplogroups. The HD, DP and RMP values were 0.998 6, 0.994 2 and 0.005 8, respectively. The lowest genetic differentiation degree （F_st=0.006 89） was detected between Zhejiang She population and southern Han population. Principal component analysis （PCA） and median-joining network analysis showed that the genetic distance of Zhejiang She population with Guangxi Yao, Yunnan Dai and Southern Han populations was relatively close, but the population still had some unique genetic characteristics. Conclusion The whole mtDNA genomes are highly polymorphic in Zhejiang She population. The Zhejiang She population contains complex and diverse genetic components and has a relatively close maternal genetic relationship with Guangxi Yao, Yunnan Dai and Southern Han populations. Meanwhile, Zhejiang She population has kept its unique maternal genetic components.

Identification of Cannabis Sativa L. Based on rbcL Sequence

Abstract

Objective To assess the feasibility of the rbcL sequence of chloroplast DNA as a genetic marker to identify Cannabis sativa L. Methods The rbcL sequences in 62 Cannabis sativa L. samples, 10 Humulus lupulus samples and 10 Humulus scandens DNA samples were detected, and 96 rbcL sequences of the Cannabaceae family were downloaded from Genbank. Sequence alignment was performed by MEGA X software, the intraspecific and interspecific Kimura-2-Parameter （K2P） genetic distances were calculated, and the system clustering tree was constructed. Results The rbcL sequence length acquired by sequencing of Cannabis sativa L. and Humulus scandens were 617 bp and 649 bp, respectively, and two haplotypes of Cannabis sativa L. were observed in the samples. The BLAST similarity search results showed that the highest similarity between the sequences acquired by sequencing and Cannabis sativa L. rbcL sequences available from Genbank was 100%. The genetic distance analysis showed that the maximum intraspecific genetic distance （0.004 9） of Cannabis sativa L. was less than the minimum interspecific genetic distance （0.012 9）. The results of median-joining network and system clustering tree analysis showed that Cannabis sativa L. and other members of the Cannabaceae family were located in different branches. Conclusion The rbcL sequence could be used as a DNA barcode for identifying Cannabis sativa L., and combined with comparative analysis of the rbcL sequence and system cluster analysis could be a reliable and effective detection method for Cannabis sativa L. identification in forensic investigation.

Forensic Application of Next Generation Sequencing Technology in the Typing of Y Chromosome Genetic Markers

Abstract

The paternal inheritance characteristics of Y chromosome have been widely used in the forensic genetics field to detect the genetic markers in the non-recombining block, and used in the studies such as, genetic relationship identification, mixed stain detection, pedigree screen and ethnicity determination. At present, capillary electrophoresis is still the most common detection technology. The commercial detection kits and data analysis and processing system based on this technology are very mature. However, the disadvantages of traditional detection technology have gradually appeared with the rapid growth of bio-information amount, which promotes the renewal of forensic DNA typing technology. In recent years, next generation sequencing （NGS） technology has developed rapidly. This technology has been applied to various fields including forensic genetics and has provided new techniques for the detection of Y chromosome genetic markers. This article describes the current situation and application prospects of the NGS technology in forensic Y chromosome genetic markers detection in order to provide new ideas for future judicial practice.

Progress on Copy Number Variation and Its Application in Forensic Medicine

Abstract

Recently, researches on copy number variation （CNV） have extended to every field, such as etiological exploration and precise treatment of complex diseases, as well as genetic breeding and evolution. The unique genetic characteristics of CNV have made people gradually believe that it could be used as a biological genetic marker to solve related problems. With the development of detection technology, application of CNV in forensic medicine will increase gradually. In this paper, the concept and development of CNV, as well as its application in forensic medicine are summarized, to provide new ideas for the practical application of CNV in the future.

Research Progress on Age Estimation Based on DNA Methylation

Abstract

Age estimation is of great significance in the fields of criminal investigation and forensic identification. It can provide the age information of individuals to judicial departments to facilitate the development of judicial work. In recent years, age estimation methods expanded from the morphological level to the molecular biology level. With the rapid development of epigenetics represented by DNA methylation, and the advancement of DNA methylation detection technology together with the detection platform, many age estimation methods based on DNA methylation biomarkers, or using several biological fluids, such as blood, blood stains, saliva, semen stains, etc. are developed. Currently, researches related to age estimation based on DNA methylation are relatively widely carried out. This paper summarizes the researches on age estimation based on DNA methylation, in order to provide references for related studies and forensic applications.

Evaluation and Countermeasures of the Implementation of Forensic Clinical Identification Standards Based on the Perspective of Accreditation

Abstract

The new Standardization Law, implemented in 2018, has added a standard post-implementation evaluation system, aiming to continuously improve the quality of standards through post-implementation evaluation. Standards in the forensic science field are closely related to accreditation activities. Forensic science standards are not only the criteria on which accreditation activities are carried out, but also one of the key contents of the inspection of forensic science institutions in accreditation activities. Since 2018, the certification and accreditation policies in the forensic science field have also been changed, which has brought impacts on the construction of a standard system based on accreditation.This paper analyzes the standard data from China National Accreditation Center from Conformity Assessment on forensic clinical identification accreditation assessment. It points out that the current coverage of laboratory accreditation activities is limited, the development in different provinces is unbalanced, and there is overlap and crossover in the standards in use. It is emphasized that the construction of the national forensic science standardization technical committee, the improvement of the forensic science standard system, the establishment of the standard implementation evaluation index system, and promotion of the coordination of standards, and the certifications and accreditations should be accelerated, in order to continue to promote the standardization and accreditation activities in the field of forensic science.

Application of Multiple Genetic Markers in Determination of Full and Half Sibling Relationship： A Case Report

Abstract

Objective To investigate the application of the comprehensive use of multiple genetic markers in full and half sibling relationship testing through the identification of a case of suspected sibling relationship. Methods Genomic DNA were extracted from bloodstain samples from 4 subjects （ZHANG-1, ZHANG-2, male; ZHANG-3, ZHANG-4, female）. Autosomal STR loci, X-STR, Y-STR loci and polymorphisms of mtDNA HV-Ⅰ and Ⅱwere genotyped by EX20 STR kit, X19 kit, Data Y24 STR kit, and Sanger sequencing, respectively. Results According to autosomal STR based IBS scoring results, full sibling relationships were indicated among ZHANG-2, ZHANG-3 and ZHANG-4, but those were not indicated between ZHANG-1 and ZHANG-2 or ZHANG-3 or ZHANG-4. According to autosomal STR based FSI and HSI, with ITO method and discriminant function method, full sibling relationships among ZHANG-2, ZHANG-3 and ZHANG-4 were indicated, and half sibling relationships between ZHANG-1 and ZHANG-2 or ZHANG-3 or ZHANG-4 were also indicated. X-STR and mtDNA sequencing results showed that all the 4 samples came from a same maternal line, and Y-STR results showed that ZHANG-1 and ZHANG-2 did not come from a same paternal line, which supported the half sibling relationship between ZHANG-1 and ZHANG-2 or ZHANG-3 or ZHANG-4, verified by parental genotype reconstruction based on autosomal STR genotyping. Conclusion For the identification of sibling relationships, it is effective to have reliable results with the mutual verification and support of multiple genetic markers （autosomal STR, sex chromosomal STR and mtDNA sequence） and calculations （IBS, ITO, discriminant function method and family reconstruction）.

Evaluating the Efficiency of REPLI-g® Single Cell Kit for Trace DNA Amplification

Abstract

Objective To evaluate the efficiency of REPLI-g® Single Cell Kit for sample DNA amplification, and explore its application value in forensic trace DNA amplification. Methods Three DNA extraction kits were selected to extract DNA from peripheral blood of 10 unrelated individuals. The DNA yield and purity of the three DNA extraction kits were compared. According to the results of comparison, one DNA sample was selected to concentrate and dilute, then used as the initial sample of whole genome amplification （WGA）. REPLI-g® Single Cell Kit was used to amplify the initial sample at the whole genome level. The amplification yield and amplification times were calculated, and the distribution of DNA fragments was detected by agarose gel electrophoresis. Goldeneye® DNA ID System 20A Kit was used to perform the STR typing of the initial sample and DNA samples amplified at the whole genome level to evaluate the performance of REPLI-g® Single Cell Kit in trace DNA amplication in terms of purity and yield as well as the success rate of STR typing. Results After comparison, one DNA sample was selected from QIAsymphony® DNA Investigator® Kit extracts to concentrate and dilute as the initial sample of WGA. After amplifying the whole genome of a series of initial samples by REPLI-g® Single Cell Kit, the lowest average of amplification yield reached 8.77×103 ng, while the average of the corresponding amplification times reached 1.40×106. DNA fragments were large and concentrated. The STR typing success rate of WGA samples became lower with the decrease of initial samples used, but when the amount of samples was lower than 0.5 ng, the STR typing success rate of samples after DNA WGA was higher than that of samples without DNA WGA. Conclusion REPLI-g® Single Cell Kit can increase the yield of template DNA. Especially for trace DNA, the STR typing success rate can be improved to a certain extent.

Research Progress on Discrimination of Monozygotic Twins

Individual identification plays an import role in the practice of forensic medicine, and often provides crucial evidence for the analysis and detection of criminal cases. However, for individual identification in complex situations, such as monozygotic （MZ） twins assumed to be genetically identical, it is impossible to distinguish one from the other by using traditional forensic DNA typing system. Therefore, how to discriminate the MZ twins has become and will continue to be one of the difficult problems in forensic field. This paper summarized the genetic and epigenetic changes recently identified in MZ pairs, which might provide a new insight to forensic discrimination of MZ twins.

Analysis of Forensic Sciences Literature in SCIE from 2008 to 2017

OBJECTIVES

To analyze the literature on forensic sciences indexed in Science Citation Index Expanded （SCIE） in recent 10 years, and to understand the research status, characteristics and trends in the field of forensic sciences.

METHODS

Literature on forensic sciences from 2008 to 2017 in Web of Science （WoS） was retrieved. The documents number and geographical distribution, document types, source titles, organizations, research areas, authors, funding agencies, and the high cited articles were detected. The impact factors （IF） of journals were retrieved in Journal Citation Reports （JCR）. The data were analyzed with descriptive statistics.

RESULTS

From 2008 to 2017, there were 21 001 documents on forensic sciences in SCIE. The main document type was articles, with English as the major language. With regards to research areas, pathology has the largest number of papers worldwide, and genetics and heredity has the largest number of publications in mainland China. Among the 18 journals where the documents was published, Forensic Science International ranks the first on publication count, and Forensic Science International Genetics has the highest IF （5.637） in the JCR 2017. In 2017, the number of papers from mainland China increased by 48.50% compared with 2016, which was higher than the global increase （32.63%） and the top-5 countries in terms of number of publications （the US, Germany, the UK, Australia, Italy）. The average document count per organization is 1.98 worldwide and 1.17 in mainland China, respectively. The publication number per author is 0.53 worldwide and 0.36 in mainland China, respectively. Around 28.17% of the publications were funded, with National Natural Science Foundation of China （NSFC） as the Top 1 funding agency （192 papers）. Among the documents with citations, the most cited publication has been cited for 366 times.

CONCLUSIONS

The yearly numbers of publications on forensic sciences are increasing during recent 10 years. Focusing on the mainland China, there would be more high-quality papers with the steady funding of NSFC.

Research Progress on InDel Genetic Marker in Forensic Science

Genetic markers in forensic DNA typing experienced the variable number of tandem repeats （VNTR） sequences and the short tandem repeats （STR） sequences. With the emerge of sequencing technology, the third generation of genetic markers were found out, which usually have two alleles including single nucleotide polymorphism （SNP） and insertion/deletion （InDel）, also known as biallelic genetic markers. Because of the insertions or deletions of DNA fragments, InDel genetic marker reveals DNA fragment length polymorphism and widely distributes across the whole genome. InDel genetic marker is numerous and has the characteristics of STR and SNP genetic markers, which has been applied in the fields of genetics and anthropology. This review focuses on the research progress of InDel genetic marker in forensic science, aiming to review and summarize the main research findings in recent years and provide clues for future researches.

Formula Derivation for the Probability Distribution of IBS Score in Unrelated Individual Pairs

OBJECTIVES

To derive the probability equation given by STR allele frequencies of identity by state （IBS） score shared by unrelated individual pairs.

METHODS

By comparing the STR genotypes of two unrelated individuals, three mutually exclusive combinations could be obtained： （1） sharing 2 identical alleles, a₂=1, otherwise a₂=0; （2） sharing 1 identical allele, a₁=1, otherwise a₁=0; （3） sharing 0 identical allele, a₀=1, otherwise a₀=0. And the IBS score of the one STR locus in this unrelated individual pair could be given by the formula： ibs=2a₂+a₁. The probability of a₂=1 （p₂）, a₁=1 （p₁） and a₀=1 （p₀） were derived and expressed in powers of the allele frequencies. Subsequently, for a genotyping system including n independent STR loci, the characteristics of binomial distribution of IBS score shared by a pair of unrelated individuals could be given by p₂_l and p₁_l （l=1, 2, …, n）.

RESULTS

All the general equations of p₂, p₁ and p₀ were derived from the basic conceptions of a₂, a₁ and a₀, respectively. Given f_i （i=1, 2, …, m） as the ith allele frequency of a STR locus, the general equations of p₂, p₁ and p₀ could be respectively expressed in powers of f_i： [Formula: see text],[Formula: see text] and [Formula: see text]. The sum of p₂, p₁ and p₀ must be equal to 1. Then, the binomial distribution of IBS score shared by unrelated individual pairs genotyped with n independently STR loci could be written by： IBS~B（2n, π）, and the general probability, π, could be given by the formula： [Formula: see text].

CONCLUSIONS

In the biological full sibling identification, the probability of null hypothesis corresponding to any specific IBS score can be directly calculated by the general equations presented in this study, which is the basement of the evidence explanation.

[Assessment on Application of 24 Y-STR Loci in Forensic Science]

OBJECTIVES

To select a Y-STR marker system with strong haplotype identification ability, appropriate mutation rate and high compatibility and to assess its forensic application.

METHODS

The 24 Y-STR loci were tested by self-built fluorescent multiplex system, and the forensic assessment was conducted by 139 pairs of father-son samples collected in Jinan, Shandong province.

RESULTS

Totally 176 alleles were identified among the 24 Y-STR loci in the sample of 139 unrelated individuals labeled with father, and the gene diversity （GD） distributed between 0.083 7 （DYS645）-0.966 9 （DYS385a/b）. According to the 24 Y-STR loci, 139 different haplotypes were detected from 139 unrelated male individuals labeled with father in Han population of Shandong province and with no shared haplotype observed. The overall haplotype diversity （HD） was 1 and the discrimination capacity （DC） was 1. A total of 5 one-step mutations events were observed among the 24 Y-STR loci in 139 pairs of father-son. The average mutation rate was 0.001 5 [95% CI （0.000 5, 0.003 5）].

CONCLUSIONS

The system of 24 Y-STR loci shows a strong individual recognition ability and low mutation rate in the population in Jinan, Shandong province, and it has good application value in forensic science.

[Forensic Application of SiFaSTR™ 23plex DNA ID System in Han Population of Eastern China]

OBJECTIVES

To investigate the genetic polymorphism of 21 autosomal STR loci and DYS391 locus of SiFaSTR™ 23plex DNA ID system in Han population of eastern China and to evaluate its application value in forensic science.

METHODS

Typing test of 2 000 unrelated individuals was performed using SiFaSTR™ 23plex DNA ID system. The population genetic parameters of STR loci were statistically analysed. A total of 3 198 parentage confirmed cases were detected with that system and the mutation conditions were observed in 21 autosomal STR loci.

RESULTS

All the 21 autosomal STR loci showed no significant departure from Hardy-Weinberg equilibrium （P>0.05）. The Ho ranged from 0.617 5 to 0.927 0. The DP ranged from 0.796 4 to 0.986 9, as well as the PIC distributed from 0.561 1 to 0.912 3. The CDP was 0.999 999 999 999 999. The CPE_duo was 0.999 997 431 701 961, while CPE_trio was 0.999 999 999 654 865. Five alleles were detected in DYS391 locus, with the allele frequency from 0.004 0 to 0.729 0, and GD was 0.418 9. Except D13S317 and D10S1248, seventy-six mutation events were observed at the rest nineteen autosomal STR loci. Among them, seventy-five （98.68%） were one step mutation, and only one （1.32%） was three steps mutation. The mutation rate ranged from 0.246 5×10⁻³ to 2.711 4×10⁻³, and the averaged mutation rate was 0.892 1×10⁻³ （95% CI： 0.70×10⁻³-1.10×10⁻³）. In 33 trio mutation cases, the proportion of the paternal mutation and the maternal mutation was 2.09:1.

CONCLUSIONS

The involved STRs are highly polymorphic in Eastern Han population with acceptable mutation rates by the SiFaSTR™ 23plex DNA ID system, which is suitable for paternity testing and individual identification.

Structural correlates of trait impulsivity in patients with bipolar disorder and healthy controls: a surface-based morphometry study

BACKGROUND

Patients with bipolar disorder (BD) frequently exhibit impulsive behaviors independent of their mood state, and trait impulsivity is increasingly recognized as a crucial BD biomarker. This study aimed to investigate structural correlates of trait impulsivity measured using the Barratt Impulsiveness Scale (BIS) in healthy controls (HCs) and patients with BD.

METHOD

We recruited 59 patients diagnosed with BD I or BD II (35.3 ± 8.5 years) and 56 age- and sex-matched HCs (33.9 ± 7.4 years). Participants underwent structural magnetic resonance imaging and clinical evaluations, and their BIS scores were evaluated. An automated surface-based method (FreeSurfer) was used to measure cortical thickness and generate thickness maps for each participant. Brain-wise regression analysis of the association between cortical thickness and BIS scores was performed separately for BD and HC groups by using a general linear model.

RESULTS

Patients with BD obtained significantly higher BIS scores than HCs. In HCs, higher BIS scores were associated with a thinner cortex in the left inferior, middle and medial frontal cortices. By contrast, in BD patients, higher BIS scores were associated with a thicker cortex in the right insula. Patients with BD showed a thinner cortex than HCs in all these four structures.

CONCLUSIONS

The findings indicate that the left prefrontal cortex plays a cardinal role in trait impulsivity of healthy individuals. Patients with BD have a different structural correlate of trait impulsivity in the right insula. However, the use of various psychotropics in patients with BD may limit our interpretation of BD findings.

[Full Sibling Identification by IBS Scoring Method and Establishment of the Query Table of Its Critical Value]

OBJECTIVES

To establish a query table of IBS critical value and identification power for the detection systems with different numbers of STR loci under different false judgment standards.

METHODS

Samples of 267 pairs of full siblings and 360 pairs of unrelated individuals were collected and 19 autosomal STR loci were genotyped by Goldeneye™ 20A system. The full siblings were determined using IBS scoring method according to the 'Regulation for biological full sibling testing'. The critical values and identification power for the detection systems with different numbers of STR loci under different false judgment standards were calculated by theoretical methods.

RESULTS

According to the formal IBS scoring criteria, the identification power of full siblings and unrelated individuals was 0.764 0 and the rate of false judgment was 0. The results of theoretical calculation were consistent with that of sample observation. The query table of IBS critical value for identification of full sibling detection systems with different numbers of STR loci was successfully established.

CONCLUSIONS

The IBS scoring method defined by the regulation has high detection efficiency and low false judgment rate, which provides a relatively conservative result. The query table of IBS critical value for identification of full sibling detection systems with different numbers of STR loci provides an important reference data for the result judgment of full sibling testing and owns a considerable practical value.

Analysis of the 19 Y-STR and 16 X-STR loci system in the Han population of Shandong province, China

The sex-linked short tandem repeats (STR), Y-STR and X-STR, are important for autosomal STRs in forensic paternity testing. We evaluated the forensic parameters of 19 Y-STRs and 16 X-STRs in the Han population of Shandong province, China. A Goldeneye 20Y kit (DYS391, DYS389I, DYS390, DYS389II, DYS348, DYS456, Y-GATA-H4, DYS447, DYS19, DYS392, DYS393, DYS388, DYS439, DYS635, DYS448, DYS460, DYS458, DYS437, DYS385 a/b) was used to analyze the forensic parameters of 534 unrelated males. A Goldeneye17X system (DXS6795, DXS9902, DXS8378, HPRTB, GATA165B12, DXS7132, DXS7424, DXS6807, DXS6803, GATA172D05, DXS6800, DXS10134, GATA31E08, DXS10159, DXS6789, DXS6810, amelogenin) was used to analyze 97 unrelated males and 214 females. In addition, we used the kits to examine 5 cases with abnormal amelogenin test results, as well as a male child with agenosomia typed by autosomal STR. We found 203 Y-STR haplotypes with allele frequencies ranging from 0.0019 to 0.7959, and GD ranging from 0.3429 to 0.9667. Expect in DXS6803, the allele frequencies of the other 15 X-STR loci showed no differences between females and males. PD_F ranged from 0.5504 to 0.9638, while PD_M ranged from 0.3176 to 0.8377. With the exception of DXS6803 and DXS6810, the allele frequencies of other X-STR loci were in accordance with Hardy-Weinberg equilibrium in females. One amelogenin negative case was characterized as a deletion of Y-DYS458. This paper provided data regarding the genetic polymorphism of Y-STRs and X-STRs in the Han population, and demonstrated the importance of Y-STR and X-STR in forensic autosomal STR analysis.

[Review of Second Generation Sequencing and Its Application in Forensic Genetics]

The rapid development of second generation sequencing （SGS） within the past few years has led to the increasement of data throughput and read length while at the same time brought down substantially the sequencing cost. This made new breakthrough in the area of biology and ushered the forensic genetics into a new era. Based on the history of sequencing application in forensic genetics, this paper reviews the importance of sequencing technologies for genetic marker detection. The application status and potential of SGS in forensic genetics are discussed based on the already explored SGS platforms of Roche, Illumina and Life Technologies. With these platforms, DNA markers （SNP, STR）, RNA markers （mRNA, microRNA） and whole mtDNA can be sequenced. However, development and validation of application kits, maturation of analysis software, connection to the existing databases and the possible ethical issues occurred with big data will be the key factors that determine whether this technology can substitute or supplement PCR-CE, the mature technology, and be widely used for cases detection.

A comparative study on anticoagulant activities of three Chinese herbal medicines from the genus Panax and anticoagulant activities of ginsenosides Rg1 and Rg2

CONTEXT

Chemical compositions of three herbal plants from the family Araliaceae genus Panax [Panax ginseng C. A. Mey, P. quinquefolius L. and P. notoginseng (Burk.) F. H. Chen] are quite similar; however, their medicinal natures vary greatly. The reason for differences has been explained in traditional Chinese medicine theory and partially verified by modern pharmacological investigations, such as antiplatelet aggregation. Aside from platelet aggregation, a variety of plasma coagulation factors are also involved in blood coagulation. The anticoagulation profiles of three herbs have not been investigated.

OBJECTIVE

The current research compared the inhibitory effects of three herbal extracts from Panax spp. and the purified ginsenosides from P. ginseng on blood coagulation.

MATERIALS AND METHODS

Human plasma was mixed with the water extracts (0.05 and 0.1 mg/mL) from roots of P. ginseng, P. quinquefolius and P. notoginseng and ginsenosides Rg1 and Rg2 (0.05 and 0.1 mg/mL), the blood clotting time of activated partial thromboplastin, prothrombin and thrombin were measured by a biochemical analyzer.

RESULTS

The water extracts (0.05 mg/mL) of P. ginseng, P. quinquefolius and P. notoginseng could significantly extend blood clotting time as compared to the control group. Among three herbal medicines, 0.05 mg/mL of water extract from P. ginseng exhibited the strongest anticoagulation effects, followed by P. notoginseng, while P. quinquefolius presented the weakest effects. Both ginsenosides Rg1 and Rg2 could significantly extend blood clotting time in all three tests; ginsenoside Rg2 exhibited relative stronger anticoagulation effects as compared to ginsenoside Rg1.

DISCUSSION AND CONCLUSION

Among three herbs tested, P. ginseng as well as its active component ginsenoside Rg2 shows the strongest anticoagulation activity; current results indicate that P. ginseng and ginsenoside Rg2 have great potential to be an anticoagulation drug.

Genotyping of urinary samples stored with EDTA for forensic applications

Individual identification of urinary samples is necessary when sample switching or handling are suspected during a judicial process. To improve the rate of successful genotyping of urinary samples, we examined the stability of DNA in urinary samples stored for up to 30 days. Urinary samples from 20 healthy individuals (10 males and 10 females) were stored at -80°C with different concentrations of EDTA (0, 10 and 40 mM). Urinary DNA was extracted at days 0, 3, 9, and 30 after collection. The Quantifiler Human DNA Quantification Kit was used for measuring DNA concentration. Twenty STR loci were co-amplified using amelogenin-specific PCR with the Goldeneye 20A Kit. Significant differences in DNA concentration were observed between samples from females and males. In the case of female urinary DNA preservation with 10 and 40 mM EDTA the mean detection rate reached 0.95 after up to 30 days; for the male urinary samples, the mean detection rate of urinary DNA preserved with 40 mM EDTA was significantly higher than with 10 mM. We concluded that 40 mM EDTA is the best concentration for preservation of the DNA in urinary samples.

The fate of Cu, Zn, Pb and Cd during the pyrolysis of sewage sludge at different temperatures

In the present study, a sequential extraction procedure, recommended by the Community Bureau of Reference (BCR), was used for the fractionation of the heavy metals Cu, Zn, Pb and Cd in sewage sludge and its residues produced after pyrolysis at different temperatures from 250 to 700 degrees C. The results show that, in the sludge sample, the sum of the percentages of the reducible and oxidizable fractions for all metals except Cu was very high (65.4% for Cd, 85.7% for Pb, 78.7% for Zn), whereas the sum of the percentages of the oxidizable and residual fractions for Cu was very high (88.8%). The same result could be attained in the residues. Statistical analysis shows that at low temperatures the variation in pyrolysis temperature did not effectively contribute to the distribution of metal speciation in the residues. Meanwhile a modified Toxicity Characteristic Leaching Procedure (TCLP) was employed to determine the leachability of these four metals. The result indicates that the TCLP concentration of Cu, Zn, Pb and Cd dropped sharply after the temperature reached 350 degrees C, 550 degrees C, 500 degrees C and 400 degrees C respectively, which means pyrolysis can enhance the stability of these four metals when the temperature is high enough.

Design of a stability-detecting device for dental implants

Resonance frequency (RF) analysis technology was used to design a dental implant stability detector. The device uses a miniature-sized electromagnetic triggering rod to elicit vibration in a dental implant. Vibrational signals were recorded via an acoustic receiver. To assess the in vivo performance of the test apparatus, animal models were used. Implants were placed in the left tibia of 12 rabbits using a conventional surgical procedure. Standard 3.2 mm × 8 mm implants were placed in each test tibia with pre-tapping cavities of 3.2 mm and 3.7 mm diameters to simulate either a ‘well-fitting’ or a ‘loosely fitting’ situation. The RF values of the test implants were detected by the newly developed device which was directly mounted on the healing abutments of the implants. The results showed that the RF values of the implants under well-fitting conditions significantly increased (p<0.01) 3 weeks after surgery and reached a plateau at around 6-7 weeks. Meanwhile implants with higher initial RF values had shorter healing times and higher final RF values at the plateau. Based on these findings, it was concluded that the idea of using the current designed device for detecting the degree of bone healing during the osseointegration process seems feasible.

Patient and health system delays in the diagnosis and treatment of tuberculosis in Southern Taiwan

SETTING

Tainan city, Tainan county and 13 townships of Kaohsiung county, Southern Taiwan.

OBJECTIVE

To measure delays in the diagnosis and treatment of sputum-positive tuberculosis (TB) and to determine factors associated with delays in seeking health care (patient delay) and in starting anti-tuberculosis treatment (health system delay).

DESIGN

A population-based patient interview study.

RESULTS

Median patient delay was 7 days (range 0-730). Median health system delay was 23 days (range 0-489), 13 for smear-positive patients and 37 for smear-negative patients (P < 0.005). Median total delay was 44 days (range 0-730). Age <65 years was associated with longer patient delay. Negative smear, absence of haemoptysis, not having a chest radiograph at the first medical consultation and visiting clinics for first consultation were associated with a longer health system delay. Age <65 years, negative smear and cough as the only presenting symptom were associated with longer total delay.

CONCLUSION

Patient delay was substantially shorter than health system delay. To reduce health system delay, clinics need to be involved and the referral mechanism must be strengthened. Physicians should maintain high alert for TB and perform prompt sputum smear examinations.

Methods of developing core collections based on the predicted genotypic value of rice ( Oryza sativa L.)

The selection of an appropriate sampling strategy and a clustering method is important in the construction of core collections based on predicted genotypic values in order to retain the greatest degree of genetic diversity of the initial collection. In this study, methods of developing rice core collections were evaluated based on the predicted genotypic values for 992 rice varieties with 13 quantitative traits. The genotypic values of the traits were predicted by the adjusted unbiased prediction (AUP) method. Based on the predicted genotypic values, Mahalanobis distances were calculated and employed to measure the genetic similarities among the rice varieties. Six hierarchical clustering methods, including the single linkage, median linkage, centroid, unweighted pair-group average, weighted pair-group average and flexible-beta methods, were combined with random, preferred and deviation sampling to develop 18 core collections of rice germplasm. The results show that the deviation sampling strategy in combination with the unweighted pair-group average method of hierarchical clustering retains the greatest degree of genetic diversities of the initial collection. The core collections sampled using predicted genotypic values had more genetic diversity than those based on phenotypic values.

PAH emission from the incineration of three plastic wastes

A batch-type, controlled-air incinerator was used for the treatment of polyvinyl chloride (PVC), high-density polyethylene (HDPE), and polypropylene (PP) plastic wastes. The concentration and composition of 21 individual polycyclic aromatic hydrocarbons (PAHs) in the raw wastes, flue gas (gas and particle phases), and ash were determined. Stack flue-gas samples were collected by a PAH stack-sampling system. Twenty-one individual PAHs were analyzed primarily by a gas chromatograph/mass spectrometer (GC/MS). The CO concentration correlated well with the total PAH (R2 > .89), and thus can be used as a surrogate indicator for PAH emission. Excess amounts of air supply in the incineration of plastic wastes could decrease not only the concentration of the PAHs in the bottom ash but also the emission factor (EF) of the total PAH in the stack flue gas. Of the three plastic wastes, HDPE was found to have the highest mean EF of the total PAHs (462.3 mg/kg waste) from the stack flue gas. Incinerating PVC would result in a higher EF of PAHs (195.4 mg/kg waste) in the bottom ash. When PVC plastic wastes were incinerated, higher-ringed PAHs constituted a larger percentage in the bottom ash as compared to those from PP and HDPE plastics. By judging the output and input (O/I) ratio of the PAHs from the incineration trials of plastic wastes, the PAHs involved in incineration of three plastic wastes were almost entirely destroyed; and a low residual amount between 0.00018 and 0.00032 remained in the emission.

Isolated right atrial tear following blunt chest trauma: report of three cases

Blunt chest trauma causing isolated right atrial tear and cardiac tamponade in three patients is reported. All three patients presented with hypotension, elevated central venous pressure and altered consciousness. Echocardiographic examination demonstrated pericardial effusion in all three cases. All three patients underwent operation with a median sternotomy approach without using cardiopulmonary bypass. At operation, two patients had one tear in the right atrium, the other had two tears in the right atrium. All three patients recovered uneventfully. Early use of echocardiography to detect the presence of hemopericardium and cardiac tamponade in patients with suspected atrial rupture following blunt chest trauma is advocated.

Minimization of cobalt nuclide emissions in supercritical water oxidation of spent resin

A rapid and complete destruction of organics in the supercritical water oxidation (SCWO) of the Co-exchanged resin was found experimentally. Due to an extremely low solubility of CoSO4 salt formed and separated effectively in the SCWO process, a minimal release of the nuclide Co would be warranted. In addition, recycling of Co nuclides is also possible by decomposition of the CoSO4 species at elevated temperatures (> 1040 K).

Batch phenol degradation by candida tropicalis and its fusant

Phenol degradation by Candida tropicalis and its fusant, which is produced using protoplast fusion as a selective technique, is evaluated under batch and high concentration conditions. The respirometric data show that oxygen uptake activities of both yeast strains peak at pH 7.0 and 32 degrees C, but the fusant is more active than the control strain. Although the data show that both yeast strains are capable of sustaining discernible degradation in the presence of phenol inhibition, however, the C. tropicalis fusant is capable of attaining better phenol degradation than the control strain and it is less susceptible to phenol inhibition. Under the conditions tested, C. tropicalis is completely inhibited at phenol concentrations >/=3,300 mg/L, whereas for the C. tropicalis fusant complete inhibition is absent until phenol concentrations are >/=4, 000 mg/L. The observed cell yields of both yeast strains are virtually identical and remain fairly constant at approximately 0.5 mg MLVSS/mg C6H5OH (MLVSS: mixed liquor volatile suspended solids). Copyright 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 60: 391-395, 1998.

Acute myocardial infarction following blunt chest trauma

A 32-year-old male riding a motorcycle was involved in an accident resulting in blunt torso trauma. He had fractures of the skull, first right rib, and left femoral bone. Electrocardiogram showed acute anteroseptal myocardial infarction (MI). Subsequent coronary angiogram demonstrated laceration at the proximal portion of the left anterior descending coronary artery. Echocardiogram showed depressed left ventricular function as well as hypokinesis over septal and apical areas. His recovery was smooth.

Isokinetic profile of dorsiflexors and plantar flexors of the ankle--a comparative study of élite versus untrained subjects

A comparative study was made of the isokinetic characteristics of the ankle (plantar-flexion and dorsiflexion) in young men. Six cyclists, seven gymnasts, 10 soccer players and 25 non-athletic young men were tested on the Cybex II+ dynamometer. Peak torque, torque acceleration energy (TAE), total work and average power were measured. Cyclists had slightly higher (5%) mean plantar flexion than the others, but this was not significant. The situation was reversed for dorsiflexion. Moreover, the average dorsiflexion per unit of plantar flexion was significantly higher in the gymnasts than it was in the cyclists for both torque and work. This suggests that at a specific level of plantar flexion, the gymnasts had stronger dorsiflexion compared with the cyclists and that in sports involving jumping and running, increased attention should be given to strengthening the antagonist muscle groups (dorsiflexors) in order to achieve greater agonist-to-antagonist muscle balance thus preventing injury. The non-athletic subjects had substantially lower endurance capability in both flexors as measured by the endurance ratio. This implies that identifiable specialization in particular muscles results from training or participating in specialized sports.

Double primary tumors of the liver

A rare case of double primary tumors of the liver is reported. A 69-year-old male presented with fever and right upper quadrant pain. On admission blood culture grew Salmonella group B. Laboratory data showed leucocytosis, mild elevation of aspartate aminotransferase, alanine aminotransferase and sugar, positive-HBsAg, and normal range CEA and AFP. Abdominal sonography disclosed a well demarcated solid mass and another cystic lesion with a ragged wall in the left lobe of liver. Abdominal CT revealed a mixed density solid mass in the medial segment, and laterally located cystic mass with internal septa. A preoperative diagnosis of double tumors of the left lobe of the liver was made and the patient underwent a left hepatic lobectomy. Hepatocellular carcinoma and cystadenocarcinoma were diagnosed by histopathological examination. The patient has been well without tumor recurrence after one and a half year's follow-up.

Physiological profiles of Hong Kong élite soccer players

Most physiological profiles of élite soccer players originate from Western Europe and North America. Unfortunately, there is a scarcity of descriptive data on the physical characteristics of Asian soccer players. Therefore, the purpose of this study was to evaluate the physiological profiles of élite soccer players in Hong Kong. It was conducted in conjunction with the selection of the Hong Kong team before the 1990 Beijing Asian Games. In all, 24 professional soccer players were selected from a pool of 180 players as subjects for the study. The following means(s.d.) were observed: height 173.4(4.6) cm; weight 67.7(5.0) kg; body fat 7.3(3.0)%; forced vital capacity (FVC) 5.1(0.6) l; maximum oxygen uptake (VO2max) 59.1(4.9) ml kg-1 min-1; anaerobic threshold (AT 80.0(7.2)% of VO2max; alactic power index 13.5(2.4) W kg-1; lactic work index 298(27) J kg-1; peak isokinetic dominant knee extensor and flexor strengths 2.72(0.36) Nm kg-1 and 1.65(0.20) Nm kg-1. On average the physique of Hong Kong soccer players appeared to be smaller and lighter than those found in Europe, which may be one of the key factors that contribute to the lack of success of Hong Kong soccer teams in international competition.