Determination of phenotypes of salivary amylase in liquid saliva and saliva stains

An isoelectric focusing method is described for typing salivary amylase in liquid saliva and saliva stains. The estimated gene frequencies in a British population, calculated on the basis of three alleles operating at a single locus, were Amy 1, 0.909; Amy 2, 0.065; Amy 3, 0.026. This system may be useful in forensic investigations.     

An aqueous-organic extraction method for the isolation and identification of psilocin from hallucinogenic mushrooms

A simple aqueous extraction method for the isolation and identification of psilocin from Psilocybe cubensis mushrooms is reported. This method employs a dephosphorylation of the phosphate ester to psilocin, which facilitates a greater product yield and simplifies identification. Psilocin extracted by this method is sufficiently concentrated and free of cocontaminants to allow identification by infrared spectroscopy and gas chromatography/mass spectrometry.     

Detection of dermcidin for sweat identification by real-time RT-PCR and ELISA

We evaluated the performance of real-time RT-PCR and ELISA assays for detection of dermcidin (DCD) in sweat and body-fluid stains. DCD, a small antibiotic peptide secreted into human sweat, was detected by real-time RT-PCR in 7-day-old stains containing as small as 10 μL of sweat, and the assay showed high specificity when testing 7-day-old stains containing 30 μL of other body-fluid. ELISA using anti-human dermcidin mouse monoclonal antibody detected DCD sweat diluted up to approximately 10,000-fold and could specifically detect DCD in 10 μL of body-fluid stains. The performance of the two assays was tested during winter on samples that simulated forensic case samples: an undershirt and a sock worn for 20 h, a handkerchief used to wipe the brow several times within 12 h, a cap and a cotton glove worn for 4 h, and a white robe worn at intervals for 2 years. The result showed that the former assay detected DCD in all sites of the undershirt examined (armpit, back, and breast), and the latter gave a relatively high OD value in the armpit among the three sites. For the socks, although the latter assay gave very high OD values in both the center and toe of the foot sole, the former could not detect DCD in both of them. These results indicate that highly damp conditions, such as inside a shoe, might promote the degradation of mRNA in samples such as socks. In the other case samples, sweat was adequately detected by both assays.This study is the first demonstration of the use of real-time RT-PCR to sensitively identify sweat among body-fluid stains, and it confirmed that dermcidin was an excellent marker for sweat identification. In addition, the usefulness of ELISA was also verified. Positive sweat identification using these assays is expected to assist forensic practice.     

Genetic polymorphism of human parotid salivary amylase detected by isoelectric focusing electrophoresis and silver staining

In 332 samples of human parotid saliva collected at random from a Japanese population, the genetic polymorphism of salivary alpha-amylase was detected by isoelectric focusing electrophoresis in a pH range of 5.2-7.2 polyacrylamide gel followed by silver staining. This polymorphism, that was tentatively designated Amy1 S, consisted of extra three isozymes of a normal pattern (Amy1 N) and isoelectric points of these three isozymes were 5.5, 5.8 and 6.1, respectively. The inheritance was controlled by a dominant allele at an autosomal locus. The frequency of the genes determining these phenotypes were studied as follows: Amy1 S = 0.014 +/- 0.004, Amy1 N = 0.986 +/- 0.004.     

An ELISA using avidin-biotin complex for the determination of ABH group from saliva

The ABH group in a trace amount of saliva could be determined by an enzyme-linked immunosorbent assay (ELISA) using an avidin-biotin-peroxidase complex (ABC) technique. In this method ABH blood group substances as a solid phase are adsorbed to wells of a microtiter plate made of polystyrene. The primary antibody corresponding to the blood antigen adheres onto the wells, and reacts with the biotinylated secondary antibody. The previously formed ABC reagent is then added to the above wells, and finally the absorbance produced by the interaction of the peroxidase activity with a chromogenic substance is measured at 492 nm. This method proved to be clearly more sensitive for the detection of ABH blood groups in secretor-saliva than the conventional hemagglutination inhibition test. Also the ABH group of non-secretor-saliva could be easily determined by this method.     

唾液酯酶多态性在个体识别中的应用研究

目的 探讨唾液酯酶（ Set）多态性在法医学亲权鉴定和个体识别方面的应用价值。方法 应用聚丙烯酰胺凝胶盘状电泳及固蓝 RR染色方法,调查了 114名中国人 Set的表型分布及基因频率,用χ 2检验进行统计学分析。结果 中国人酯酶表型频率 Set F 22.81％, Set FS 50.88％, Set S 26.31％ ;基因频率为 SetF 0.482 5, SetS 0.517 5;非父排除机率为 0.187 5,个体识别率为 0.619 9。结论 Set有较高的父权排除率和个体识别率,可作为法医学亲权鉴定和个体识别的重要标记系统之一。     

An enzyme-linked immunosorbent assay (ELISA) for human semen identification based on a biotinylated monoclonal antibody to a seminal vesicle-specific antigen

Monoclonal antibody mouse antihuman semen-5 (MHS-5) (immunoglobulin G1 [IgG1]) was biotinylated using N-biotinyl-w-aminocaproic acid-N-hydroxysuccinimide ester. This monoclonal antibody-biotin conjugate recognized low molecular weight peptide bands between 10.5 and 20 kilodaltons on immunoblots of liquefied semen. Immunodominant peptides had molecular weights of 10.5, 11.5, and 13.5 kilodaltons. An enzyme-linked immunosorbent assay (ELISA) developed with the biotinylated-MAb and streptavidin peroxidase demonstrated sensitivity curves with lower limits of 10 ng of seminal fluid protein per microtiter well using 50 ng per well of monoclonal antibody-biotin conjugate. Cross-reactivity studies on a panel of human biological fluids and tissues demonstrated no cross-reactivity or false positives using the monoclonal antibody-biotin conjugate. The sensitivity of the monoclonal antibody-biotin ELISA was compared to ELISA based upon a polyclonal secondary antibody-peroxidase conjugate. These findings indicate that this ELISA assay, based on a biotinylated monoclonal antibody to a seminal vesicle-specific antigen, may be useful for semen identification.     

An enzyme-linked immunosorbent assay (ELISA) for prostate-specific antigen.

A sandwich ELISA for human prostate-specific antigen (PSA) is described. Optimal assay conditions, resulting in a sensitive assay with a low background, are presented. The method uses a hyperimmune antiserum produced in the New Zealand white rabbit, against human semen PSA. The IgG fraction of the antiserum was conjugated with horseradish peroxidase and used in the sandwich ELISA method. The anti-PSA IgG showed no cross reactions with saliva, normal blood, female urine, vaginal fluid, or menstrual blood. On occasions, a blood sample showed a non-specific cross-reaction, which was detected by non-immune rabbit IgG. This reaction could be caused by rheumatoid factors, as indicated by experiments with a series of known IgG and IgM rheumatoid antibodies, although other heterophilic antibodies could not be eliminated. The recovery of PSA added to blood plasma, saliva and vaginal fluid was affected by three factors; (a) protein concentration (dilution) of body fluid; (b) nature of the protein; and (c) amount of PSA added.     

Geometric method for determining the skull-portrait aspect in craniofacial identification of the body

Correspondence of the reference graphic images by the aspect is an important condition of craniofacial personality identification. The authors propose methods of determining the skull-portrait aspect by X and Y axes simultaneously. This allows 2 potentialities of comparing the photograph and the skull picture: 1) positioning the skull in a strictly determined aspect estimated by analysis of coordinates of reference points on the photoportrait and 2) positioning the skull and re-estimation of the photoportrait coordinates into the "zero" aspect (zero turning, inclination, and lateral deviation). Hence, all coordinates of the reference points of examined graphic images in the database can be estimated for the zero position and the same scale, which helps automate the search for analogs.     

Shadow positioning technique: a method for postmortem identification

Radiology is increasingly being used as a means of postmortem identification. We have devised a shadow positioning technique by which a postmortem radiograph of a skeletal part can exactly duplicate an antemortem radiograph, thus, faciliating identification by comparison of the antemortem and postmortem radiographs. The antemortem radiograph can be of any skeletal part and taken in any position.     

A method for group identification of hair infected with Microsporum

A method for identifying the group appurtenance of biological objects from subjects suffering from various diseases is developed. The method can be used in examination of putrefactive objects (blood, secretions, hair, etc.) and in cases when the group appurtenance cannot be identified by other methods.     

A novel method for the identification of saliva by detecting oral streptococci using PCR

We have used DNA amplification methods to detect common oral bacterial strains to test for the presence of saliva in forensic samples. Streptococcus salivarius and Streptococcus mutans were detected in various forms of saliva samples, whereas these streptococci were not detected in semen, urine, vaginal fluid, or on skin surfaces. Therefore, we demonstrated that these streptococci are promising new marker for the forensic identification of saliva. Our data indicated that S. salivarius is more reliable than S. mutans as an indicator of saliva presence, because the detection rates for S. salivarius and S. mutans by this method were 100% and 90%, respectively. Furthermore, S. salivarius was detected in all saliva stain samples, whereas S. mutans was only identified in 60% of the stains. Finally, using this method we were able to successfully detect S. salivarius and S. mutans in mock forensic samples. We therefore suggested that this method is useful for the identification of saliva in forensic science.     

Direct ELISA kits as a sensitive and selective screening method for abstinence control in urine

In 2009 cutoff values of assessment criteria to testify abstinence control in order to estimate driving ability were standardized in Germany. The cutoff values are lower than required in existing guidelines like SAMHSA and there is critical discussion about detection of low concentrations by using immunoassay, especially concerning amphetamines in urine (50 ng/ml). In this study Direct ELISA kits were tested for their applicability to identify the absence of amphetamines, cannabinoids, opiates, cocaine, methadone and benzodiazepines in urine. Results were confirmed by LC/MS or GC/MS analyses. Sensitivity, specificity, predictive values (positive as well as negative) and overall misclassification rates were evaluated by contingency tables and were compared to ROC-analyses. Sensitivity results as well as specificity results were satisfying showing sensitivity values higher than 96% for each analyte. The amphetamine test we used showed sensitivity and specificity of 100% and 88%, respectively, even if amphetamine tests usually react with high cross-reactivity. Our study results include high discrimination at required cutoff values between positives and negatives for each drug group and demonstrate that immunological tests complying with requirements of current decreased urine cutoff values for assessment of driving ability do exist.     

An economised craniofacial identification system

It has been attempted to develop an economised craniofacial identification system, as a special automated version of photo/video superimposition technique, that can deal with common cases of personal identification with the aid of a skull and a nearly front view face photograph of the suspected victim.The proposed method is economic in respect of (i) cost of hardware configuration, (ii) processing time as well as (iii) manual labour involved. Over and above, it has got a capability to take care of ambiguities due to soft tissue thickness during the selection of facial features, which is a part of the procedure.In order to reconstruct a 2-D cranial image, superimposable over the facial one, the new method does not need any reconstruction of a digitised 3-D cranial image. It works simply by a suitable segment-wise processing of a 2-D cranial image with the aid of the symmetry perceiving adaptive neuronet (SPAN), that has recently been introduced in connection with nearly front view facial image recognition. The final comparison of the facial and the superimposable cranial images is as versatile as the same for facial image recognition by SPAN.A practical application of this extended version of SPAN has been demonstrated in the present paper.     

单克隆抗体双位点一步ELISA方法检测MN血型

目的 :对法医学样品中微量液体血、血痕进行MN分型。方法 :利用抗M、抗N及抗血型糖蛋白A单抗 ,采用双位点一步ELISA方法。结果 :此法可检测的最低全血量约0 065μl,血痕约10～50ng。对455份新鲜血液及200份新鲜血痕的标本均正确检出 ;对58例陈旧血痕的检出率为96 6 %。结论 :此法准确率高且简便、快速 ,具有很大的实用价值。     

A new method for collection and identification of gunshot residues from the hands of shooters

This work presents a novel collection method for gunshot residues (GSR) using a sampling procedure based on ethylenediaminetetraacetic acid (EDTA) solution as a complexing agent on moistened swabs. Detection was via a sector-field inductively coupled plasma mass spectrometry (HRICP-MS). The proposed collection and analytical method allowed detection of antimony (Sb), barium (Ba) and lead (Pb) after .38 shot tests. at detection limits of less than 1 microg L(-1) in four different areas of the hands of volunteers. This paper includes a discussion concerning hand areas near the thumb and forefinger as being more suitable for GSR collection as well as a comparison between differences observed using 2% diluted EDTA. 2% nitric acid solution, and simple deionized water as collecting solutions, proving the superior efficiency of EDTA in GSR recoveries.