1.Bacterial Succession on Rat Carcasses and Applications for PMI Estimation.
Lin ZHANG ; Juan-juan GUO ; TELET-SIYIT ; Yu-long PENG ; Dan XIE ; Ya-dong GUO ; Jie YAN ; Lagabaiyila ZHA ; Ji-feng CAI
Journal of Forensic Medicine 2016;32(1):1-6
UNLABELLED:
Abstract:
OBJECTIVE:
To investigate the bacterial succession on rat carcasses and to evaluate the use of bacterial succession for postmortem interval (PMI) estimation.
METHODS:
Adult female SD rat remains were placed in carton boxes. The bacterial colonization of circumocular skin, mouth and vagina was collected to be identified using culture-dependent biochemical methods. The changes in community composition were regularly documented.
RESULTS:
The bacterial succession in three habitats showed that Staphylococcus and Neisseria were predominated in early PMI, especially Staphylococcus aureus and Neisseria lactamica in 6 hours after death. Lactobacillus casei developed on the 3-4 days regularly, and kept stable at a certain level in late PMI.
CONCLUSION
The involvement of normal and putrefactive bacteria in three body habitats of rat remains can be used for PMI estimation.
Animals
;
Autopsy
;
Cadaver
;
Death
;
Forensic Medicine/methods*
;
Neisseria lactamica
;
Postmortem Changes
;
Rats
;
Rats, Sprague-Dawley
;
Staphylococcus aureus
;
Time Factors
2.Mathematical models of the teenager's skeletal age evaluation based on CT scan and imaging reconstruction of medial clavicular epiphysis.
Hua WEI ; Telet SIYIT ; Lei WAN ; Chong-liang YING ; Ya-hui WANG
Journal of Forensic Medicine 2013;29(5):340-343
OBJECTIVE:
To explore the correlation between CT volume rendering (VR) statistics and living age and to build the mathematical models for skeletal age evaluation based on the growth rules of medial clavicular epiphysis of teenagers in China.
METHODS:
The thin layer CT scan and VR 3D imaging reconstruction of both sides of sternal ends of clavicles were examined for 684 teenagers aged from 15 to 25 in East and South China. The parameters of sternal end of clavicle including the longest diameter of epiphysis, the longest diameter of metaphysis, their length radio, area of epiphysis, area of metaphysic, their area ratio, and other data were measured and calculated in order to establish mathematical models of skeletal age evaluation. Fifty trained subjects were tested to verify the accuracy of the mathematical models.
RESULTS:
In the same age group, the length ratio and the area ratio had significant difference in genders (P < 0.05). The established mathematical models showed that the growth rules of medial clavicular epiphysis were highly correlated with the living ages. The accuracies of these models were higher than 70.5% +/- 1.0 year) and 82.5% (+/- 1.5 year).
CONCLUSION
The mathematical models have easy operability and high accuracy. It can be used to confirm and sustain the conclusion of atlas method. Meanwhile, it is of great significance to study the other single skeletal age evaluation in the future.
Adolescent
;
Age Determination by Skeleton/methods*
;
China
;
Clavicle/growth & development*
;
Epiphyses/growth & development*
;
Female
;
Forensic Anthropology/methods*
;
Humans
;
Image Interpretation, Computer-Assisted/methods*
;
Male
;
Models, Theoretical
;
Osteogenesis
;
Sensitivity and Specificity
;
Tomography, X-Ray Computed/methods*
;
Young Adult