Identification of five types of forensic body fluids based on stepwise discriminant analysis.

Peripheral blood, menstrual blood, semen, saliva and vaginal secretions are the five most common body fluids found at crime scenes, and the identification of these five body fluids is of great significance to the reconstruction of a crime scene and resolution of the case. However, accurate identification of these five body fluids is still a challenge. To address this problem, a mathematical model for differentiating five types of forensic body fluids based on the differential expression characteristics of multiple miRNAs in five body fluids (peripheral blood, menstrual blood, semen, saliva and vaginal secretions) was developed. A total of 350 forensic body fluids (70 of each type) were collected and tested, and relative expression of 10 miRNAs (miR-451a, miR-205-5p, miR-203-3p, miR-214-3p, miR-144-3p, miR-144-5p, miR-654-5p, miR-888-5p, miR-891a-5p, miR-124a-3p) in all samples was detected by SYBR Green real-time qPCR. Three hundred samples (60 samples of each body fluid) were used as the training set to screen meaningful identification markers by stepwise discriminant analysis, and a discriminant function was established. Fifty samples (10 samples of each body fluid) were used as a validation set to examine the accuracy of the model, and 25 samples (the types of samples were unknown to the experimenter) were used for a blind test. Except for miR-144-3p, the other miRNAs were selected to construct discriminant analysis models. The self-validation accuracy of the model was 99.7 %, cross-validation accuracy was 99.3 %, accuracy of the identification validation set was 100 %, and accuracy of the blind test result was 100 %. This study provides a reliable and accurate identification strategy for five common body fluids (peripheral blood, menstrual blood, semen, saliva, and vaginal secretions) in forensic medicine.

A stepwise strategy to distinguish menstrual blood from peripheral blood by Fisher's discriminant function.

Blood samples are the most common and important biological samples found at crime scenes, and distinguishing peripheral blood and menstrual blood samples is crucial for solving criminal cases. MicroRNAs (miRNAs) are important molecules with strong tissue specificity that can be used in forensic fields to identify the tissue properties of body fluid samples. In this study, the relative expression levels of four different miRNAs (miR-451, miR-205, miR-214 and miR-203) were analysed by real-time PCR, with 200 samples from 5 different body fluids, including two kinds of blood samples (peripheral blood and menstrual blood) and three kinds of non-blood samples (saliva, semen and vaginal secretion). Then, a strategy for identifying menstrual and peripheral blood based on Fisher's discriminant function and the relative expression of multiple miRNAs was established. Two sets of functions were used: Z1 and Z2 were used to distinguish blood samples from non-blood samples, and Y1 and Y2 were used to distinguish peripheral blood from menstrual blood. A 100% accuracy rate was achieved when 50 test samples were used. Ten samples were used to test the sensitivity of the method, and 10 ng or more of total RNA from peripheral blood samples and 10 pg or more of total RNA from menstrual blood samples were sufficient for this method. The results provide a scientific reference to address the difficult forensic problem of distinguishing menstrual blood from peripheral blood.

Long-term postoperative outcomes of bilateral lateral rectus recession vs unilateral recession-resection for intermittent exotropia.

AIM: To discuss the long-term postoperative results of bilateral lateral rectus recession (BLR) and unilateral lateral rectus recession-medial rectus resection (RR) in therapy of intermittent exotropia. METHODS: We retrospectively analyzed 213 cases of intermittent exotropia who underwent surgery between 2008 and 2010. The patients were grouped into BLR group and RR group. Motor outcomes were divided into three groups on the basis of the angle of deviation after surgery: overcorrection (esotropia/phoria >5(Δ)), orthophoria (esotropia/phoria ≤5(Δ) to exotropia/phoria ≤10(Δ)), and undercorrection/recurrence (exotropia/phoria >10(Δ)). Titmus test was used to evaluate stereoacuity, the stereoacuity <800s of arc meaned the patients had stereopsis. Surgical outcome including motor criteria and sensory status were compared at postoperative 6, 12, 24mo and at 36mo examination between groups. RESULTS: At 12, 24mo after surgery, the motor outcomes had no difference (P>0.05) between groups. However, the motor outcomes at 6, 36mo were signally different in each group, indicating the success rate in RR group at 6mo was higher than that in BLR group (83.02% vs 82.24%, P<0.05) but the result was contrary at the 3y examination (60.75% vs 43.40%, P<0.05). No statistical significance were found in the sensory outcomes between the groups at mean of 3.7y follow-up. CONCLUSION: The motor outcomes in RR group were better than in BLR group at 6mo after surgery, while the 3y outcomes were better in BLR group. This may be due to the recurrence rate of the BLR was lower than the RR group's.

KIF21A mutations in two Chinese families with congenital fibrosis of the extraocular muscles (CFEOM).

PURPOSE: Two Chinese families (XT and YT) with congenital fibrosis of the extraocular muscles (CFEOM) were identified. The purpose of this study was to determine if previously described Homo sapiens kinesin family member 21A (KIF21A) mutations were responsible for CFEOM in these two Chinese pedigrees. METHODS: Clinical characterization and genetic studies were performed. Microsatellite genotyping for linkage to the CFEOM1 and CFEOM3 loci was performed. The probands were screened for KIF21A mutations by bidirectional direct sequencing. Once a mutation was detected in the proband, all other participating family members and 100 unrelated control normal individuals were screened for the mutation. RESULTS: All affected individuals in family XT shared the common manifestations of CFEOM1. Family YT had two affected individuals, a mother and a daughter. The daughter had CFEOM1, while her mother never had congential ptosis but did have limited extraocular movements status post strabismus surgery. Haplotype analysis revealed that pedigree XT was linked to the 12q CFEOM1 locus and the affected memberes harbored the second most common missense mutation in KIF21A (2,861G>A, R954Q). Family YT harbored the most common missense de novo mutation in KIF21A (2,860C>T, R954W). Both of these mutations have been previously described. CONCLUSIONS: The observation of these two KIF21A mutations in a Chinese pedigree underscores the homogeneity of these mutations as a cause of CFEOM1 and CFEOM3 across ethnic divisions.

Therapeutic effects of two anastomoses of lacrimal passage on canalicular laceration.

OBJECTIVE: To evaluate the therapeutic effects of two anastomoses (canaliculus-to-lacrimal sac anastomosis and end-to-end anastomosis) on nasolacrimal laceration for over 7 mm from the broken end to the dacryon. METHODS: A total of 71 patients (44 males and 27 females, aged 16-55 years, mean equal to 34.32 years) with fresh canalicular laceration were treated in our hospital from March 2003 to April 2008. Under a microscope, 37 patients were treated with lacrimal sac anastomosis (the treatment group) and 34 with end-to-end anastomosis (the control group), detaining silicone tubes till 3 months later. RESULTS: The cure rate of the treatment group (89.19%) was significantly higher than that of the control group (55.56%). Class I cure rates were 70.27% in the treatment group and 47.06 % in the control group, and the difference between the two groups was significant (P less than 0.05). Postoperative inflammatory reactions had significant influences on the two kinds of anastomosing methods, but no significant difference was found between the two groups (P larger than 0.05). CONCLUSIONS: When the distance from the broken end to the dacryon is over 7 mm, especially when it is necessary to find the paranasal broken end of the lacrimal canaliculus with dacryocystotomy, canaliculus-to-lacrimal sac anastomosis is a better treatment method than end-to-end anastomosis for laceration of lacrimal canaliculus.

[The changes of extracellular matrix molecules in the resected medial rectus muscle of patients with concomitant exotropia].

OBJECTIVE: In order to have a better understanding about the role of the extracellular matrix molecules in the intermittent and constant exotropia, we measured the amounts of fibronectin and proteoglycan in the resected medial rectus muscles of patients with concomitant exotropia. METHODS: Thirty-one exotropic patients (including intermittent exotropia 17 cases and constant exotropia 14 cases) and 21 normal were chosen. In exotropic group, there were 7 cases with positive family history. Tissues of the medial rectus muscles were obtained from patients with concomitant exotropia during resection surgery and the specimen of medial rectus muscle from 21 normal persons was as control. All the tissues were weighted and then pulverized to obtain supernatant for enzyme linked immunosorbent assay (ELISA). The total amounts of fibronectin and proteoglycan were measured. The correlation of fibronectin and proteoglycan with age, gender, positive family history in different groups of exotropia was analyzed. RESULTS: The amount of fibronectin in the resected medial rectus muscle of patients with concomitant exotropia was significantly lower than that of normal individual (P < 0.01), and the difference of proteoglycan amount between patients and the normal control was not significant (P > 0.05). Patients with intermittent exotropia showed significantly higher concentration of fibronectin than those with constant exotropia (P < 0.01), and the amount of proteoglycan had no significant difference between two groups (P > 0.05). The amounts of proteoglycan decreased significantly with the advance of age (r = -0.8712, P < 0.01), while the amounts of fibronectin had no correction with age (r = -0.1718, P > 0.05). Neither gender nor positive family was correlated with the amounts of proteoglycan and fibronectin (P > 0.05). CONCLUSIONS: The change of fibronectin may be related to the concomitant exotropia and the development from intermittent to constant exotropia. An attention should be paid to the roles of fibronectin in the development of strabismus.

[Clinical investigation of the syndrome of congenital fibrosis of extraocular muscles].

OBJECTIVE: To analyze the clinical manifestations of congenital fibrosis of the extraocular muscles (CFEOM) both in their pedigrees and sporadic cases. METHODS: Six families and seven sporadic cases of CFEOM were retrospectively analyzed in the study. The clinical features including genetic characteristics, sex, age of first visit, major complains, subclassifications, features of ptosis and aberrant innervation were evaluated. RESULTS: The six families of CFEOM were autosomal dominant inherited traits and classified to the general fibrosis of the extraocular muscles with the inferior rectus muscles affected most severely. All patients except for 1 had binocular involvement. 2 out of the 29 affected members had ptosis and 7 had no aberrant innervation. The male-to-female ratio of the 7 sporadic cases was 2:5. 3 cases had monocular involvement. Among all the sporadic cases 3 cases were general fibrosis syndrome combined with inferior rectus fibrosis, 1 case was general fibrosis syndrome combined with superior rectus fibrosis, 3 cases were esotropia fixus. 1 patient had monocular ptosis while 4 patients had no ptosis. 5 patient had no aberrant innervation while the other two had. CONCLUSIONS: Clinically, the cases of CFEOM are relatively few but the clinical manifestations are complex. The combination of clinical characteristics and genetic analysis are the basis for the establishment of diagnosis. Further research is needed to understand the pathogenesis of the disease.