Objective To estimate time of gauze swabs left in abdomen with comparison of the number of foreign body giant cells,theirs nuclei and the proportion of type Ⅰ collagenous fibers to type Ⅲ and argentaffin fibers in different times.Methods F344 rat models dependent 2,8,30,120 days were established by gauze swab fixed in the abdomen,and were studied on gauze swab wrapped by greater omentum,the number of foreign body giant cells and theirs nuclei by HE staining,and the proportion of type Ⅰ collagenous fibers to type Ⅲ and argentaffin fibers by sirius red and silver staining respectively.The results were analyzed by image analysis system.Results The results showed that number of foreign body giant cells,theirs nuclei and the proportion of type Ⅰ collagenous fibers to type Ⅲ and argentaffin fibers increased gradually(P<0.01)followed the time delayed.The Proportion of type Ⅰ collagenous fibers to argentaffin fibersis Power Function of Days of guaze swab left in rat abdomen(r=0.972).Conclusion The number of foreign body giant cells,theirs nuclei and the proportion of type Ⅰ collagenous fibers to type Ⅲ and argentaffin fibers contribute to the estimation of foreign body(eg.gauze swab)left in abdomen.

Objective To investigate the numbers, sizes and types distribution of diatoms in drowned and postmortem immersed rabbits’ lungs. Methods Sixty-two rabbits were randomly divided into drowning group (n=30), postmortem immersion group (n=30) and land death group (n=2), and the diatoms in each lung lobe were analyzed quantitatively and qualitatively by microwave digestion and scanning electron microscopy. Results In the drowning group, the diatoms were detected in each lung lobe with Cyclotella and Melosira in the majority. In the postmortem immersion group, Cyclotella was in the majority. And the diatoms weren’t detected in some lung lobes in postmortem immersion. There were significant dif-ferences in the detection rates of upper lobe of left lung, middle lobe and cardiac lobe of right lung in two groups (P<0.05). Conclusion Based on the microwave digestion and scanning electron microscopy, the numbers, sizes and types distribution of diatoms in drowned and postmortem immersed rabbits ’ lungs can be analyzed and used as references for testing theory.

OBJECTIVETo compare the efficacy of three methods for forensic diatom test, namely strong acid digestion-centrifuge enrichment-light microscopy (SD-CE-LM), microwave digestion-membrane filtration-automated scanning electron microscopy (MD-ME-SEM), and microwave digestion-membrane filtration-light microscopy (MD-MF-LM).

METHODSSixty samples were randomly divided into 3 groups for diatom test using three methods, and the sample preparation time, degree of digestion and recovery rate of diatoms were compared.

RESULTSThe sample preparation time was the shortest with MD-MF-LM and the longest with SD-CE-LM (P<0.05). MD-ME-SEM and MD-MF-LM allowed more thorough tissue digestion than SD-CE-LM. MD-ME-SEM resulted in the highest total recovery rate of diatom, followed by MD-MF-LM and then by SD-CE-LM (P<0.05); the recover rate of different diatom species was the highest with MD-ME-SEM, followed by MD-MF-LM and SD-CE-LM (P<0.05).

CONCLUSIONSD-CE-LM has a low recovery rate of diatoms especially for those with lengths shorter than 40 µm or densities less than 1/5. With a high recovery rate and accuracy in diatom test, MD-ME-SEM is suitable for diagnosis of suspected drowning cases. MD-MF-LM is highly efficient, sensitive and convenient for forensic diatom test.

Centrifugation ; Diatoms ; isolation & purification ; Drowning ; Forensic Sciences ; methods ; Humans ; Microscopy ; Microscopy, Electron, Scanning ; Microwaves ; Specimen Handling

Objective To establish a Real-time quantitative PCR method (qPCR) for the detection of diatom UPA barcoding genes and evaluate its application in the drowning diagnosis. Methods The homologous sequences of diatoms UPA gene was obtained by Blast from GeneBank, based on which the universal primers for diatoms were designed. DNA were extracted from 2 common human symbiotic bacteria (Escherichia coli, Bifidobacterium longum), 3 species of planktonic bacteria, 15 species of planktonic algae, tissue samples (lung, liver and kidney) from human cadavers (28 drowning victims, 1 victims by non-drowning in the water, 3 victims deaths on land) in 32 cases. The specificity, sensitivity and repeatability of the designed primers were tested. The positive rates of diatoms detection in the drowning cases were calculated. The results of the real-time quantitative method were evaluated comparatively by Microwave Digestion-Vacuum Filtration-Automated Scanning Electron Microscopy (MD-VF-Auto SEM) and PCR-Capillary Electrophoresis (PCR-CE). Results The results showed that the primers UPA99 had strong specificity for the diatomaceae (Synedra radians, Navicula sp., Melosira varians, Cyclotella sp. and Nitzschia sp.) DNA. The melting curve of the amplified product was smooth; the peak was narrow; the melting temperature was (87±1)℃. The sensitivity of qPCR method was 1.56×10-5ng/μL with the detection range of 1.56×102ng/mL~1.56×10-5ng/μL, in contrast with the PCR-CE method (1.56×10-3ng/μL). This real-time PCR method showed high repeatability and stability with the coefficient of variation less than 2%. The detection rate of lung, liver and kidney was 89.3%, 71.4% and 64.3% respectively. Conclusion The established qPCR method, based on the universal primers designed for diatom UPA gene, has high specificity, high sensitivity and good repeatability. With a promising prospect for application, qPCR is suitable for drowning diagnosis.

This paper systematically analyzed the understanding of qi from the perspectives of matter， energy， information and relationship reality， introduced the original holistic principle of systematic traditional Chinese medicine （TCM）， and considered the latest research results of qi （three-layer material theory）， trying to optimize the structure framework of the qi theoretical system and exhibit the occurrence and development rules of original qi. It emphasizes the hierarchical order of qi transformation following the original holistic principle， and takes this to guide the clinical understanding of “qi diseases”， helping doctors grasp the basic pathogenesis of the disease， that is abnormal qi movement， and helping them establish the awareness of providing systematic TCM treatment to patients by taking qi regulation as the key. At the same time， it discusses people within the structure of time and space， and points out that the treatment of diseases must comply with the principle of “the harmony of heaven， earth， and human beings”.