Short tandem repeats (STRs) have been widely used in forensic sciences such as stain analysis and paternity testing. Although most of STR typing could give the reliable and clear results, some unusual typing have been observed in forensic practice. The anomalous typing could result from a lot of causes, including DNA genetic variation, poor quality or quantity of DNA template, different typing system or method, nonspecific reaction in PCR or anomalous electrophoresis migration. The unusual results may disturb the right interpretation of STR typing.
DNA Fingerprinting/methods* ; Forensic Medicine/methods* ; Gene Frequency ; Genotype ; Humans ; Polymerase Chain Reaction/methods* ; Polymorphism, Genetic ; Tandem Repeat Sequences/genetics*

OBJECTIVETo establish a rat model of low calcium diet related hyperoxaluria and explore its features.

METHODSBy means of randomized blocks design, totally 24 SD male rats were divided into low calcium diet group, medium calcium diet group, and high calcium diet group. Each group was sequentially fed on different calcium diets for 3 days. The urinary volume within 24 hours was recorded, the consistency of urinary oxalate by high-efficiency liquid chromatography, and the consistency of urine creatinine by automatic biochemical analyzer. The consistency was corrected to the output of urinary oxalate of rats in 24 hours, and the results were evaluated by repeated measurement of variance analysis and multivariate analysis of variance.

RESULTSThe output of urinary oxalate of rats in 24 hours varied with time (F=7.893, P0.05). The output of urinary oxalate of rats in 24 hours varied with group division (F=3.565, P<0.05). The output of urinary oxalate in 24 hours in three groups on the third day was significantly higher than that on the first day (P<0.05).

CONCLUSIONBy controlling the calcium intake, we successfully established the model of low calcium diet related hyperoxaluria in rat.

Animals ; Calcium Carbonate ; administration & dosage ; Diet ; Disease Models, Animal ; Hyperoxaluria ; etiology ; urine ; Male ; Rats ; Rats, Sprague-Dawley

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Ascites ; pathology ; Biopsy ; Biopsy, Fine-Needle ; Child ; Cytodiagnosis ; methods ; Diagnosis, Differential ; Female ; Humans ; Leukemia-Lymphoma, Adult T-Cell ; pathology ; Lymphoma, B-Cell ; pathology ; Lymphoma, Large B-Cell, Diffuse ; pathology ; Lymphoma, T-Cell ; pathology ; Male ; Middle Aged ; Pleural Effusion ; pathology ; Young Adult

BACKGROUNDAdjacent segment degeneration could seriously affect the long-term prognosis of lumbar fusion. Dynamic fixation such as the interspinous fixation, which is characterized by retaining the motion function of the spinal segment, has obtained satisfactory short-term effects in the clinical setting. But there are few reports about the biomechanical experiments on whether dynamic fixation could prevent adjacent segment degeneration.

METHODSThe surgical segments of all 23 patients were L4/5. Thirteen patients with disc herniation of L4/5 underwent Wallis implantation surgery, and 10 patients with spinal stenosis of L4/5 underwent posterior lumbar interbody fusion (PLIF). L3-S1 segmental stiffness and displacement were measured by a spine stiffness gauge (SSG) device during surgery when the vertebral plate was exposed or during spinal decompression or internal fixation. Five fresh, frozen cadavers were used in the self control experiment, which was carried out in four steps: exposure of the vertebral plate, decompression of the spinal canal, implantation of a Wallis fixing device, and PLIF of L4/5 after removing the Wallis fixing device. Then, L3-S1 segment stiffness was measured by an SSG device.

RESULTSThe experiments showed that the average stiffness of the L4/5 segment was (37.1 ± 8.9) N/mm after exposure of the vertebral plate, while after spinal decompression, the average stiffness fell to (26.2 ± 7.1) N/mm, decreasing by 25.8% (P < 0.05). For the adjacent segments L3/4 and L5/S1, their stiffness showed no significant difference between the L4/5 segment decompression and the exposure of the vertebral plate (P > 0.05). After Wallis implantation of L4/5, the stiffness of the cephalic adjacent segment L3/4 was (45.8 ± 10.7) N/mm, which was 20.5% more than that after the exposure of the vertebral plate (P < 0.05); after L4/5 PLIF surgery, the stiffness of L3/4 was (35.3 ± 10.7) N/mm and was decreased by 12.4% more than that after the exposure of the vertebral plate (P < 0.05). The stiffness of the cephalic adjacent segment L3/4 after fixation in the Wallis group was significantly higher than that of the PLIF group (P < 0.05). Cadaver experiments showed that the stiffness of the cephalic adjacent segment in the Wallis group was significantly higher than that of the PLIF group after L4/5 segment fixation (P < 0.05); the stiffness of the L5/S1 segment showed no significant difference between PLIF surgery and Wallis implantation (P > 0.05).

CONCLUSIONSAfter interspinous (Wallis) fixation, the stiffness of the cephalic adjacent segment increased. After PLIF with pedicle screw fixation, the stiffness of the cephalic adjacent segment decreased. An interspinous fixation system (Wallis) has a protective effect for cephalic adjacent segments for the immediate post-operative state.

Adult ; Bone Screws ; Female ; Humans ; Lumbar Vertebrae ; surgery ; Male ; Middle Aged ; Spinal Fusion ; instrumentation ; methods

OBJECTIVE: To understand the forensic practice of DNA profiling from minimal amount of DNA. METHODS: Serial dilutions of DNA were amplified with the PowerPlex 16 System Kit, then the genotyping of short tandem repeat(STR) was performed by ABI 377 DNA automated Sequencer. RESULTS: When the mount of DNA template was less than 250 pg, allelic drop-out apparently occurred at several loci. Other disturbed peaks, such as artefact bands and imbalanced heterozygote, also presented. CONCLUSION The anomalous results may result in incorrect genotyping. Careful and comprehensive considerations are needed to interpret the STR profile of minute DNA.
Alleles ; DNA/genetics* ; Forensic Medicine ; Genotype ; Humans ; Male ; Minisatellite Repeats/genetics* ; Sequence Analysis, DNA ; Tandem Repeat Sequences/genetics*

This article review the advance in interpretation of mixed forensic stains using DNA profiling, including autosome STR profiling, sex profiling determined by PCR, Y-specific STR profiling, mitochondrial DNA profiling and single nucleotide polymorphism profiling. The statistics methods for mixed stain has also been reviewed.
Alleles ; Blood Stains ; Chromosomes, Human, Y/genetics* ; DNA/genetics* ; DNA Fingerprinting/methods* ; Female ; Forensic Medicine/methods* ; Humans ; Male ; Polymerase Chain Reaction ; Tandem Repeat Sequences

OBJECTIVE: To evaluate the diversity of combined paternity index (CPI) of multiple STR loci when different population allele frequencies was used to calculate the paternity index. METHODS: CPI of 13 CODIS (combined DNA index system) loci for 108 trio cases and 108 duo cases selected randomly were calculated by using five Chinese Han population allele frequencies, respectively. RESULTS: The CPI range for trio cases and duo cases were 2077.63-50897711626.46 and 25.12-2998685141, respectively. When different population allele frequencies were applied to the same case, the ratio of maximum CPI and minimum CPI, which was more than 100, for trio cases and duo cases were 20 cases (19.52%) and 13 cases (12.04%), respectively. CONCLUSION The variation of CPI value of the CODIS loci was obvious with different allele frequencies. To prevent the error causing by uncertain allele frequencies, a conservative CPI value should be calculated in paternity testing.
Alleles ; China ; DNA Fingerprinting ; Forensic Medicine ; Gene Frequency ; Genetics, Population ; Humans ; Paternity ; Tandem Repeat Sequences/genetics*

OBJECTIVETo investigate the DNA damage of human lens epithelial cells (LECs) caused by acute exposure to low-power 217 Hz modulated 1.8 GHz microwave radiation and DNA repair.

METHODSCultured LECs were exposed to 217 Hz modulated 1.8 GHz microwave radiation at SAR (specific absorption rate) of 0, 1, 2, 3 and 4 W/kg for 2 hours in an sXc-1800 incubator and irradiate system. The DNA single strand breaks were detected with comet assay in sham-irradiated cells and irradiated cells incubated for varying periods: 0, 30, 60, 120 and 240 min after irradiation. Images of comets were digitized and analyzed using an Imagine-pro plus software, and the indexes used in this study were tail length (TL) and tail moment (TM).

RESULTSThe difference in DNA-breaks between the exposure and sham exposure groups induced by 1 and 2 W/kg irradiation was not significant at every detect time (P > 0.05). As for the dosage of 3 and 4 W/kg there was difference in both group immediately after irradiation (P < 0.01). At the time of 30 min after irradiation the difference went on at both group (P < 0.01). However, the difference disappeared after one hour's incubation in 3 W/kg group (P > 0.05), and existed in 4 W/kg group.

CONCLUSIONNo or repairable DNA damage was observed after 2 hour irradiation of 1.8 GHz microwave on LECs when SAR < or = 3 W/kg. The DNA damages caused by 4 W/kg irradiation were irreversible.

Cell Phone ; Cells, Cultured ; Comet Assay ; DNA Damage ; radiation effects ; DNA Repair ; Dose-Response Relationship, Radiation ; Epithelial Cells ; radiation effects ; Humans ; Lens, Crystalline ; cytology ; radiation effects ; Microwaves

OBJECTIVETo investigate the possible effect of exposure to GSM 1,800 MHz radiofrequency electromagnetic fields (RF EMF) on epidermal growth factor (EGF) receptor and its possible interference by noise magnetic fields (MF).

METHODSChinese hamster lung fibroblasts (CHL) were exposed to 1,800 MHz RF EMF (modulated by 217 Hz or 50 Hz, or unmodulated), 2 microT noise MF, and RF EMF combined with 2 microT noise MF for 15 min, respectively. The specific absorption rates (SARs) of RF EMF were 0.1, 0.5, 1.0, 2.0 and 4.0 W/kg. Commercial EGF (1 ng/ml) treatment was used as positive control. EGF receptors on the cell membrane were observed under a laser scanning confocal microscope after indirect immunofluorescence staining.

RESULTSEGF receptor clustering was induced after exposure to GSM 1,800 MHz RF EMF modulated by 217 Hz or 50 Hz MF at SARs of 0.5, 1.0, 2.0, 4.0 W/kg for 15 min as induced by 1 ng/ml EGF, but not at SAR of 0.1 W/kg. And no EGF receptor clustering was found in cells after exposure to unmodulated RF EMF or 2 microT noise MF. In addition, superposition of 2 microT noise MF could inhibit the EGF receptor clustering induced by GSM 1,800 MHz RF EMF.

CONCLUSIONEGF receptor clustering in CHL cells can be induced by GSM 1,800 MHz RF EMF at the lowest SAR of 0.5 W/kg and inhibited by noise MF. The modulation of wave may play an important role in the inducement of receptor clustering after RF exposure.

Animals ; Cell Line ; Cell Membrane ; metabolism ; radiation effects ; Cricetinae ; Cricetulus ; Dose-Response Relationship, Radiation ; Electromagnetic Fields ; Fibroblasts ; metabolism ; radiation effects ; Lung ; cytology ; Radio Waves ; Receptor, Epidermal Growth Factor ; metabolism

OBJECTIVETo investigate the relationship among a 50-Hz MF-induced epidermal growth factor receptor (EGFR) clustering, acid sphingomyelinase (A-SMase) and ceramide (CER), and to explore the possible mechanism of receptor clustering.

METHODSHuman amnion (FL) cells were exposed to a 50-Hz sinusoidal magnetic field at 0.4 mT for 15 min with or without imipramine, a specific inhibitor of A-SMase and ceramide pretreatment. EGF treatment served as the positive control and DMSO treatment served as the solvent control. The EGFR was labeled with polyclonal anti-EGFR antibody and the clustering of EGFR was analyzed using immunofluorescence and confocal microscopy. The percentage of cells with EGFR clustering was counted and compared.

RESULTSBoth EGF treatment and 50-Hz MF exposure could induce EGFR clustering. However, the effect could be eliminated by imipramine pretreatment for 4 hours. When FL cells were incubated with ceramide following the imipramine pretreatment for 30 min, EGFR clustering induced by 50-Hz MF exposure could be recovered.

CONCLUSIONEGFR clustering induced by 50-Hz MF depends on A-SMase activity, and ceramide, as the hydrolyzate from A-SMase might participate in the process of EGFR clustering.

Amnion ; cytology ; Cell Line ; Cell Membrane ; metabolism ; radiation effects ; Ceramides ; metabolism ; Epithelial Cells ; metabolism ; radiation effects ; Humans ; Magnetic Fields ; adverse effects ; Receptor, Epidermal Growth Factor ; metabolism ; Sphingomyelin Phosphodiesterase ; metabolism ; physiology