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1.
China Tropical Medicine ; (12): 310-2023.
Article in Chinese | WPRIM | ID: wpr-979636

ABSTRACT

@#Abstract: Viral shedding of SARS-CoV-2 is a continuous dynamic process, which can be divided into latent stage, initial stage, peak stage and decreasing stage according to the characteristics of viral shedding. After being infected with SARS-CoV-2, the infected person generally stays in the latent period for 1-3 days, which is characterized by continuous negative nucleic acid test results and no infectiousness, and the risk of infection for close contacts is very low. At the initial stage of viral shedding is characterized by a rapid decline in the Ct value of nucleic acid tests in a short time, and clinical symptoms gradually appear. The infectiousness of the infected person gradually increases during this period, and the risk of infection for close contacts also gradually increases, but it is still in the early stage of infection, the possibility of viral shedding is low, and the risk of infection of secondary close contacts is low. The peak of viral shedding is characterized by low Ct value in nucleic acid test and obvious clinical symptoms; during this period, the infected person is the most infectious, and the risk of infection of the contact is the highest, so the scope of close contacts should be expanded appropriately. The decreasing period is characterized by the gradual increase of Ct value of nucleic acid test and the gradual disappearance of clinical symptoms; during this period, the infectiousness of the infected person gradually decreases to disappear. In an outbreak, an infected person in the decreasing phase is more likely to be an early infected person in the transmission chain. If infected individuals in the decreasing phase are found in an area without a SARS-CoV-2 epidemic, it suggests that the local outbreak epidemic has been spreading for some time and may be larger in scale. According to the characteristics of viral shedding, risk personnel can be determined more scientifically and accurately, so as to minimize the risk and reduce the waste of epidemic prevention resources.

2.
Chinese Journal of Internal Medicine ; (12): 688-692, 2023.
Article in Chinese | WPRIM | ID: wpr-985975

ABSTRACT

Objective: To investigate the lifespan of erythrocytes in megaloblastic anemia (MA) patients. Methods: A prospective cohort study analysis. Clinical data from 42 MA patients who were newly diagnosed at the Department of Hematology, Lanzhou University Second Hospital from January 2021 to August 2021 were analyzed, as were control data from 24 healthy volunteers acquired during the same period. The carbon monoxide breath test was used to measure erythrocyte lifespan, and correlations between erythrocyte lifespan and laboratory test indexes before and after treatment were calculated. Statistical analysis included the t-test and Pearson correlation. Results: The mean erythrocyte lifespan in the 42 newly diagnosed MA patients was (49.05±41.60) d, which was significantly shorter than that in the healthy control group [(104.13±42.62) d; t=5.13,P=0.001]. In a vitamin B12-deficient subset of MA patients the mean erythrocyte lifespan was (30.09±15.14) d, and in a folic acid-deficient subgroup it was (72.00±51.44) d, and the difference between these two MA subsets was significant (t=3.73, P=0.001). The mean erythrocyte lifespan after MA treatment was (101.28±33.02) d, which differed significantly from that before MA treatment (t=4.72, P=0.001). In MA patients erythrocyte lifespan was positively correlated with hemoglobin concentration (r=0.373), and negatively correlated with total bilirubin level (r=-0.425), indirect bilirubin level (r=-0.431), and lactate dehydrogenase level (r=-0.504) (all P<0.05). Conclusions: Erythrocyte lifespan was shortened in MA patients, and there was a significant difference between a vitamin B12-deficient group and a folic acid-deficient group. After treatment the erythrocyte lifespan can return to normal. Erythrocyte lifespan is expected to become an informative index for the diagnosis and treatment of MA.


Subject(s)
Humans , Longevity , Clinical Relevance , Prospective Studies , Erythrocytes , Anemia, Megaloblastic , Folic Acid , Bilirubin , Vitamins
3.
Neuroscience Bulletin ; (6): 817-831, 2023.
Article in English | WPRIM | ID: wpr-982451

ABSTRACT

Predatory hunting is an important type of innate behavior evolutionarily conserved across the animal kingdom. It is typically composed of a set of sequential actions, including prey search, pursuit, attack, and consumption. This behavior is subject to control by the nervous system. Early studies used toads as a model to probe the neuroethology of hunting, which led to the proposal of a sensory-triggered release mechanism for hunting actions. More recent studies have used genetically-trackable zebrafish and rodents and have made breakthrough discoveries in the neuroethology and neurocircuits underlying this behavior. Here, we review the sophisticated neurocircuitry involved in hunting and summarize the detailed mechanism for the circuitry to encode various aspects of hunting neuroethology, including sensory processing, sensorimotor transformation, motivation, and sequential encoding of hunting actions. We also discuss the overlapping brain circuits for hunting and feeding and point out the limitations of current studies. We propose that hunting is an ideal behavioral paradigm in which to study the neuroethology of motivated behaviors, which may shed new light on epidemic disorders, including binge-eating, obesity, and obsessive-compulsive disorders.


Subject(s)
Animals , Zebrafish , Hunting , Predatory Behavior/physiology , Neurons/physiology , Motivation
4.
Journal of Forensic Medicine ; (6): 7-12, 2023.
Article in English | WPRIM | ID: wpr-984173

ABSTRACT

OBJECTIVES@#To explore the difference in CT values between pulmonary thromboembolism and postmortem clot in postmortem CT pulmonary angiography (CTPA) to further improve the application value of virtual autopsy.@*METHODS@#Postmortem CTPA data with the definite cause of death from 2016 to 2019 were collected and divided into pulmonary thromboembolism group (n=4), postmortem clot group (n=5), and control group (n=5). CT values of pulmonary trunk and left and right pulmonary artery contents in each group were measured and analyzed statistically.@*RESULTS@#The average CT value in the pulmonary thromboembolism group and postmortem clot group were (168.4±53.8) Hu and (282.7±78.0) Hu, respectively, which were lower than those of the control group (1 193.0±82.9) Hu (P<0.05). The average CT value of the postmortem clot group was higher than that of the pulmonary thromboembolism group (P<0.05).@*CONCLUSIONS@#CT value is reliable and feasible as a relatively objective quantitative index to distinguish pulmonary thromboembolism and postmortem clot in postmortem CTPA. At the same time, it can provide a scientific basis to a certain extent for ruling out pulmonary thromboembolism deaths.


Subject(s)
Humans , Autopsy , Thrombosis , Pulmonary Embolism/diagnostic imaging , Tomography, X-Ray Computed , Angiography , Cadaver
5.
Journal of Forensic Medicine ; (6): 471-477, 2023.
Article in English | WPRIM | ID: wpr-1009380

ABSTRACT

The finite element method (FEM) is a mathematical method for obtaining approximate solutions to a wide variety of engineering problems. With the development of computer technology, it is gradually applied to the study of biomechanics of human body. The application of the combination of FEM and biomechanics in exploring the relationship between vascular injury and disease, and pathological mechanisms will be a technological innovation for traditional forensic medicine. This paper reviews the construction and development of human vascular FEM modeling, and its research progress on the vascular biomechanics. This paper also looks to the application prospects of FEM modeling in forensic pathology.


Subject(s)
Humans , Computer Simulation , Models, Biological , Biomechanical Phenomena , Finite Element Analysis , Forensic Medicine
6.
Chinese Journal of Medical Genetics ; (6): 546-547, 2022.
Article in Chinese | WPRIM | ID: wpr-928456

ABSTRACT

OBJECTIVE@#To explore the molecular reasons of weak expression of B antigen on the red cell.@*METHODS@#Serological test for blood group was carried out, including red cell and plasma grouping, and anti-A1 and anti-H testing, and confirming weak A or B antigens by adsorption and elution. Exons 1-7 were sequenced directly, and one of them was cloned and sequenced.@*RESULTS@#All of the 23 samples showed the weak B antigen by serological method. The alleles of the subgroups were identified by DNA sequencing, including 2 Bel subgroup, 4 B3 subgroup, 14 Bw subgroup, 2 CisAB subgroup and a novel allele. The novel allele showed a nucleotide substitution 662G>A in the exon 7, and the sequence was submitted to Blood Group Antigen Gene Mutation Database, and the novel allele was named Bel10.@*CONCLUSION@#Nucleotide substitution in exon results in blood subgroup, which showed that the antigens were weakened, and Bw phenotype was the most frequently subgroup.


Subject(s)
Humans , ABO Blood-Group System/genetics , Alleles , Exons , Genotype , Nucleotides , Phenotype
7.
Journal of Southern Medical University ; (12): 123-129, 2022.
Article in Chinese | WPRIM | ID: wpr-936293

ABSTRACT

OBJECTIVE@#To assess the value of DNA methylation level of HYAL2 gene as a molecular marker for differential diagnosis of malignant and benign thyroid tumors.@*METHODS@#DNA methylation of HYAL2 gene in tissue specimens of 190 patients with papillary thyroid cancer (PTC) and 190 age- and gender-matched patients with benign thyroid tumors was examined by mass spectrometry, and the protein expression of HYAL2 was detected immunohistochemically for another 55 pairs of patients. Logistic regression analysis was performed to calculate the odds ratio (OR) and evaluate the correlation of per 10% reduction in DNA methylation with PTC. Receiver operating characteristic (ROC) curve analysis was performed and the area under curve (AUC) was calculated to assess the predictive value of alterations in HYAL2 methylation.@*RESULTS@#Hypomethylation of HYAL2_CpG_3 was significantly correlated with early-stage PTC (OR=1.51, P=0.001), even in stage I cancer (OR=1.42, P=0.007). Age-stratified analysis revealed a significantly stronger correlation between increased HYAL2_CpG_ 3 methylation and early-stage PTC in patients below 50 years than in those older than 50 years (OR: 1.89 vs 1.37, P < 0.05); ROC analysis also showed a larger AUC of 0.787 in younger patients. The results of immunohistochemistry showed that patients with PTC had significantly higher protein expressions of HYAL2 than patients with benign tumors.@*CONCLUSION@#The alterations of DNA methylation level of HYAL2 gene is significantly correlated with early-stage PTC, suggesting the value of DNA methylation level as a potential biomarker for differentiation of malignant from benign thyroid tumors.


Subject(s)
Humans , Middle Aged , Adenoma, Oxyphilic/genetics , Biomarkers, Tumor/metabolism , Cell Adhesion Molecules/metabolism , DNA Methylation , GPI-Linked Proteins/metabolism , Hyaluronoglucosaminidase/metabolism , Immunohistochemistry , Thyroid Cancer, Papillary/pathology , Thyroid Neoplasms/pathology
8.
Journal of Forensic Medicine ; (6): 53-58, 2022.
Article in English | WPRIM | ID: wpr-984095

ABSTRACT

OBJECTIVES@#To explore the application value of virtual autopsy to obtain key evidence information on drowned corpses and its application value of virtual autopsy in the diagnosis of drowning.@*METHODS@#In this study, 7 corpses were selected as the research objects. The image data of corpses were collected by computed tomography (CT) before conventional autopsy. The characteristics of corpses were observed through image reading, combined with virtual measurement indexes, and compared with 15 non-drowned corpses.@*RESULTS@#The postmortem CT of drowning showed the more fluid in respiratory tract than the non-drowning, and ground-glass opacities in the lung. The statistical volume of fluid in the sinus (maxillary sinus and sphenoid sinus) was (10.24±4.70) mL in drowning cases and (2.02±2.45) mL in non-drowning cases. The average CT value of fluid in the sinus, left atrial blood and gastric contents in drowning cases were (15.91±17.20), (52.57±9.24) and (10.33±12.81) HU, respectively, which were lower than those in non-drowning cases (P<0.05).@*CONCLUSIONS@#The comprehensive consideration of multiple characteristic image manifestations and the virtual measurement indexes are helpful to the forensic pathological diagnosis of drowning. Virtual autopsy can be used as an auxiliary method in the forensic diagnosis of drowning.


Subject(s)
Humans , Autopsy/methods , Cadaver , Drowning/diagnostic imaging , Forensic Pathology/methods , Tomography, X-Ray Computed/methods
9.
Chinese Pharmacological Bulletin ; (12): 1155-1163, 2022.
Article in Chinese | WPRIM | ID: wpr-1014028

ABSTRACT

Aim To observe the effeet of changes in miR-124 expression on the proliferation, apoptosis, migration and invasion of HCC eells and its mecha¬nism.Methods The expression levels of miR-124 and ZEB2 were deteeted in HepG2 eells.CCK8, flow cytometry, Edu and Fran swell were used to deteet the effeets of miR-124 and ZEB2 on eell proliferation, ap¬optosis, migration and invasion.Dual lueiferase and target genes were used to prediet the targeting relation¬ship between miR-124 and ZEB2.The effeet of miR- 124 and ZEB2 on proliferation, apoptosis, migration and invasion-related protein expression was deteeted by Western blot.Results The expression of miR-124 in HepG2 eells was lower than that in normal liver eells L-02, while ZEB2 and miR-124 showed the opposite trend.The results of bioinformaties prediction and dual lueiferase showed that the expression of ZEB2 was neg¬ atively correlated with the expression of miR-124.Overexpression of miR-124 and silencing ZEB2 signifi¬cantly inhibited cell proliferation activity, migration and invasion ability compared with the control group; silencing miR-124 and overexpression of ZEB2 signifi¬cantly promoted cell proliferation activity, migration and invasion ability.Western blot results showed that overexpression of miR-124 and silencing ZEB2 signifi¬cantly promoted Bax expression and inhibited Bcl-2, PCNA, MMP2 and MMP9 expression levels.Silencing miR-124 and overexpression ZEB2 were the opposite.Conclusion miR-124 could negatively regulate the effects of ZEB2 on the proliferation, migration and in¬vasion of HCC cells.

10.
Chinese Journal of Traumatology ; (6): 320-327, 2021.
Article in English | WPRIM | ID: wpr-922349

ABSTRACT

Post-traumatic osteomyelitis (PTO) is a worldwide problem in the field of orthopaedic trauma. So far, there is no ideal treatment or consensus-based gold standard for its management. This paper reviews the representative literature focusing on PTO, mainly from the following four aspects: (1) the pathophysiological mechanism of PTO and the interaction mechanism between bacteria and the body, including fracture stress, different components of internal fixation devices, immune response, occurrence and development mechanisms of inflammation in PTO, as well as the occurrence and development mechanisms of PTO in skeletal system; (2) clinical classification, mainly the etiological classification, histological classification, anatomical classification and the newly proposed new classifications (a brief analysis of their scope and limitations); (3) imaging diagnosis, including non-invasive examination and invasive examination (this paper discusses their advantages and disadvantages respectively, and briefly compares the sensitivity and effectiveness of the current examinations); and (4) strategies, including antibiotic administration, surgical choices and other treatment programs. Based on the above-mentioned four aspects, we try to put forward some noteworthy sections, in order to make the existing opinions more specific.


Subject(s)
Humans , Anti-Bacterial Agents/therapeutic use , Fractures, Bone/diagnostic imaging , Osteomyelitis/therapy
11.
Journal of Forensic Medicine ; (6): 344-350, 2021.
Article in English | WPRIM | ID: wpr-985223

ABSTRACT

Objective Based on the theory of biomechanics, the finite element method was used to study the injury characteristics of different parts of brain hit by fist with different force and to predict the risk of craniocerebral injury, in order to provide reference for actual medical protection and forensic identification. Methods The finite element model of fist was constructed by using DICOM data modeling method and related software, and the effective mass and speed of fist were used to represent the kinetic energy of fist, and combined with human finite element model THUMS 4.02, the characteristics of craniocerebral injury caused by frontal and lateral blows were parametrically simulated. Results The probability of direct death from a blow to the head was low, but as fist power increased, so did the risk of craniocerebral injury. The characteristics of craniocerebral injury were also significantly different with the different fist hitting head locations. When the frontal area was attacked, the maximum equivalent stress of skull was 122.40 MPa, while that of brain tissue was 4.31 kPa. When the temporal area was attacked, the maximum equivalent stress of skull was 71.53 MPa, while that of brain tissue was 7.09 kPa. Conclusion The characteristics and risks of skull fracture and brain tissue injury are different when different parts of the brain are hit by fist. When the frontal area is hit, the risk of skull fracture is significantly higher than when the temporal area is hit. The risk of brain tissue injury is the opposite. The position with the highest probability of skull fracture is generally the place where the skull is directly impacted, and with the conduction of stress waves, it will spread to other parts of the skull, while the position with the highest risk of brain tissue injury is not the place where the brain is directly impacted.


Subject(s)
Humans , Biomechanical Phenomena , Craniocerebral Trauma/etiology , Finite Element Analysis , Head , Skull , Skull Fractures/etiology
12.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 225-234, 2020.
Article in Chinese | WPRIM | ID: wpr-872943

ABSTRACT

Pathological scar is a kind of skin fibrotic disease caused by abnormal wound healing, including hypertrophic scar and keloid. Pathological scar may lead to aesthetic flaws, limb dysfunction and local discomfort in patients. Due to the complexity of the wound healing process, the formation of scar is affected by many factors. In addition to traditional surgical, laser, cryostatic and hormone injection methods for the treatment of pathological scar, there are new therapies, such as mesenchymal stem cell therapy, fat transplantation, interferon, and botulinum toxin. They are widely used in clinical practice, but with such problems as high prices and many side effect. Traditional Chinese medicine (TCM) has a long history in treating pathological scar. In recent years, in vivo and in vitro studies have shown that TCM has effect IN reducing inflammation, inhibiting fibroblast proliferation, regulating fibroblast activation and migration, inducing fibroblast apoptosis and autophagy, promoting the degradation of extracellular matrix (ECM) and reducing angiogenesis in general. Besides, TCM has also a certain regulatory role in the signaling pathways, such as transforming growth factor-β1 (TGF-β1)/Smads, phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) and sonic hedgehog (Shh). There are still some contradictions in relevant studies, and specific mechanisms remain to be further improved. This paper summarizes the study content, findings and relevant mechanisms of different TCM based on in vivo and in vitro experiments, analyzes the advantages and disadvantages of TCM in the prevention and treatment of pathological scar, and its prospects in clinical application, so as to provide basis and ideas for future scar studies.

13.
Chinese Journal of Primary Medicine and Pharmacy ; (12): 1158-1162, 2020.
Article in Chinese | WPRIM | ID: wpr-866402

ABSTRACT

Objective:To study the size difference of bilateral axillary vein in adults, and to provide basis for the design of interventional surgical treatment.Methods:From December 2017 to December 2018, 145 inpatients (117 cases of hypertension, 28 cases of heart failure) and 87 healthy volunteers were selected from the Second People's Hospital of Lianyungang as study objects.The size of bilateral axillary vein of each study object was measured and the difference was statistically analyzed.Results:Among the 232 subjects, the dominant hand was the right hand, accounting for 95.7% (222/232). There were no statistically significant differences in the size of left and right axillary veins (all P>0.05). There were no statistically significant differences in the other indicators except age between the two groups (all P>0.05). The diameter of axillary vein was (0.67±0.15)cm in male and (0.53±0.13)cm in female, the difference is statistically significant( P=0.000). In the healthy control group, the dominant, non-dominant and large cross-sectional areas were (0.54±0.17)mm 2, (0.54±0.15)mm 2, (0.60±0.16)mm 2, respectively, which in the hypertension group were (0.55±0.14)mm 2, (0.54±0.14)mm 2, (0.59±0.14)mm 2, respectively, which in the heart failure group were (0.54±0.16)mm 2, (0.56±0.19)mm 2, (0.59±0.1)mm 2, respectively, there were no statistically significant differences among the three groups (all P>0.05). Conclusion:The difference is not obvious in the size of bilateral axillary vein, and there is no correlation between the size of bilateral axillary vein and dominant hand.The size of axillary vein in adults of different genders is different, and the size of axillary vein can be estimated by the gender of subjects, but not by the dominant hand or other data.

14.
Journal of Clinical Hepatology ; (12): 2720-2724, 2020.
Article in Chinese | WPRIM | ID: wpr-837642

ABSTRACT

ObjectiveTo investigate the clinical effect and safety of transcatheter arterial chemoembolization (TACE) combined with microwave ablation (MWA) in the treatment of advanced primary liver cancer. MethodsA total of 186 patients with advanced primary liver cancer who were treated in The Fifth Medical Center of Chinese PLA General Hospital from April 2015 to June 2019 were enrolled and divided into study group and control group using a random number table, with 93 patients in each group. Both groups of patients underwent TACE, and the patients in the study group were treated with ultrasound-guided percutaneous MWA. The two groups were compared in terms of clinical outcome and complications. Quantitative real-time PCR was used to measure the serum level of microRNA-202 (miR-202), ELISA was used to measure the serum levels of fragile histidine triad (FHIT) and P16 protein, and the changes in the above three indices at 3 months after treatment were compared. The two-independent-samples t test was used for comparison of continuous data between two groups, and the paired t-test was used for comparison within one group before and after treatment; The chi-square testwas used for comparison of categorical data between groups. ResultsThe study group had a significantly higher objective response rate than the control group (47.32% vs 27.96%, χ2=7.422, P=0.006), and there was no significant difference in disease control rate between the two groups(P>0.05). Both groups had significant increases in the serum levels of miR-202, FHIT, and P16 protein at 3 months after treatment (all P<0.05), and compared with the control group, the study group had significantly higher serum levels of miR-202 (0.84±0.14 vs 0.58±017, t=11.385, P<0.001), FHIT (1126.35±73.05 pg/ml vs 762.87±56.71 pg/ml, t=37.904, P<0.001), and P16 protein (52.86±651 pg/ml vs 39.06±5.37 pg/ml, t=15.770, P<0.001). ConclusionUltrasound-guided MWA in addition to TACE can improve the short-term response of patients with advanced primary liver cancer and increase the serum levels of miR-202, FHIT, and P16 protein, with relatively high safety.

15.
Journal of Experimental Hematology ; (6): 1363-1366, 2020.
Article in Chinese | WPRIM | ID: wpr-827111

ABSTRACT

OBJECTIVE@#To explore the appropriate procedures for preparing extracellular microvesicles (MV) derived from human mesenchymal stem cells (MSC).@*METHODS@#Human MSCs from umbilical cords were cultured in a serum-free medium and maintained in a basal medium for 72 hours after the cell confluence reached to 80%. The supernatants of cultured cells were collected and MVs were enriched. MVs were identified by flow cytometry and electron microscopy. The total protein amount in MVs was used as a parameter for the content of MVs. The supernatants were adjusted to different pH values, and the output of MVs was detected. The supernatants were also collected for enriching the MV and detecting the protein content of MV after the cells were maintained in the basic medium for different time.@*RESULTS@#Flow cytometric analysis showed that the MVs expressed CD9, CD63 and CD81, morphologically presented round under an electron microscope and the diameter of MV was around 100 nm. After enrichment of MV, the protein content of MVs in the supernatants was 416.8±128.1, 255.4±77.9 and 142.8±46.4 μg per 10 MSC,respectively at pH of supernatant 3, 7 and 9 (P<0.05). The protein content of the supernatants per 10 MSC was 173.6±44.5, 262.4±49.6 and 364.2±37.8 μg respectively after starvation culture for 48, 72 and 96 hrs (P<0.05).@*CONCLUSION@#MVs can be readily collected after MSCs were starved for 96 hours, and the pH of the supernatants is adjusted at 3.0.


Subject(s)
Humans , Cell-Derived Microparticles , Cells, Cultured , Flow Cytometry , Mesenchymal Stem Cells , Umbilical Cord
16.
Chinese Acupuncture & Moxibustion ; (12): 1299-1303, 2020.
Article in Chinese | WPRIM | ID: wpr-877531

ABSTRACT

OBJECTIVE@#To compare the clinical efficacy between rolling needle pricking-cupping (RNP-C) and traditional pricking-cupping (TP-C) for cervical spondylosis of neck type.@*METHODS@#A total of 96 patients with cervical spondylosis of neck type were randomly divided into an RNP-C group, a TP-C group and an electroacupuncture (EA) group, 32 cases in each group. Each group was treated with EA at Jingbailao (EX-HN 15), Fengchi (GB 20), Dazhui (GV 14), Jianjing (GB 21) and @*RESULTS@#Compared before treatment, the scores of NPQ and VAS in each group were all reduced at 2 and 4 weeks into treatment and follow-up (@*CONCLUSION@#TP-C and RNP-C could both improve the cervical pain symptoms in patients with cervical spondylosis of neck type, and improve the overall function of the cervical spine, and the curative effect is similar.


Subject(s)
Humans , Acupuncture Points , Acupuncture Therapy , Cervical Vertebrae , Cupping Therapy , Spondylosis/therapy , Treatment Outcome
17.
Journal of Forensic Medicine ; (6): 820-827, 2020.
Article in Chinese | WPRIM | ID: wpr-985180

ABSTRACT

Virtual autopsy is a new technique for investigating the morphological changes of cadaveric tissues and organs by medical imaging technology. It has been widely used in the identification of causes of death. Multislice spiral computed tomography (MSCT) has become a routine inspection method in some identification institutions, although it cannot completely replace traditional autopsy, it plays a key auxiliary or substitute role in the identification of certain abnormal causes of death. Plain MSCT scan cannot visualize cadaveric vessels, but can perform cadaveric angiography to determine vascular injury or disease. This technology has entered a rapid development period in recent years, and has made a considerable progress in contrast agent, perfusion methods and imaging methods. This article summarizes several common cadaveric MSCT angiography methods, such as systemic angiography, angiography through cardiopulmonary resuscitation, targeted angiography, and angiography by cardiac puncture, and analyzes and compares the application prospects.


Subject(s)
Humans , Angiography , Autopsy , Coronary Angiography , Heart , Tomography, Spiral Computed
18.
Journal of Forensic Medicine ; (6): 666-671, 2020.
Article in Chinese | WPRIM | ID: wpr-985163

ABSTRACT

Objective To evaluate the influence of factors such as the selection of equipment, focal length and the selection of reconstruction quality in the reconstruction software on the reconstruction results of single camera photogrammetry and provide reference for the forensic application of single camera photogrammetry. Methods The 19 skulls were measured by traditional measurement method and single camera photogrammetry. The differences between the two measurement methods and within the group with same equipment but different focal length were analyzed. One skull and one corpse were selected as the research objects. According to the reconstruction quality selection conditions in the photogrammetric software, the experimental group was divided into five grades. The model reconstructed by optical scanner was defined as reference model, while the model reconstructed by single camera photogrammetry was defined as test model. The test model was aligned with the reference model, 3D deviation analysis was carried out and the mean error and root mean square (RMS) values were calculated. Results The differences between EOS 7D zoom group and traditional measurement, and within the group with same equipment had statistical significance (P<0.05). The mean error value and minimum RMS value of the skull reconstructed by single camera photogrammetry and the three-dimensional model of the corpse existed in the medium quality group, and the trend was basically the same. Conclusion The equipment and focal length has no obvious influence on the results of single camera photogrammetry. Lower reconstruction quality can easily cause distortion, while higher reconstruction quality can easily generate noise, so medium quality is preferred.


Subject(s)
Forensic Medicine , Imaging, Three-Dimensional , Photogrammetry , Skull/diagnostic imaging , Software
19.
Journal of Forensic Medicine ; (6): 204-209, 2020.
Article in English | WPRIM | ID: wpr-985106

ABSTRACT

Objective To assess the accuracy and reliability of the two 3D measuring methods, structured-light scanning and single-camera photogrammetry in forensic body surface damage and scar measurement. Methods The measuring results of 86 injuries by the ruler method, structured-light scanning and single-camera photogrammetry were compared and evaluated. The area measuring results of 13 simulated scars by the structured-light scanning, single-camera photogrammetry, Photoshop lasso pixel method and PDF reading software were compared and evaluated. The time consumed was recorded. The known specification information of the stickers was used as the standard value to compare the measuring accuracy of the ruler method, structural-light scanning and single-camera photogrammetry, and to calculate the root mean square error (RMSE). The consistency evaluation of intraclass correlation coefficient (ICC) for the repeatability of 3 measuring results obtained by different operators and the same operator. Results The differences in results of the two 3D measuring methods and the ruler method had no statistical significance; the differences between measuring results made by the structured-light scanning, single-camera photogrammetry and PDF reading software and that of the Photoshop lasso pixel method had no statistical significance. The post-processing of the single-camera photogrammetry consumed more time than that of other methods. When the long-distance group (10-40 cm) was measured, the results obtained by the ruler method were shorter than the standard value. The RMSE value results were structured-light scanning < single-camera photogrammetry < ruler method. The ICC value intragroup and intergroup were greater than 0.99. Conclusion Both structured-light scanning and single-camera photogrammetry can be applied in recording and measuring forensic body surface damage. The former has better performance in measurement accuracy and stability, while the latter has better color performance but longer post-processing time.


Subject(s)
Humans , Cicatrix , Imaging, Three-Dimensional , Photogrammetry , Reproducibility of Results , Software
20.
Journal of Forensic Medicine ; (6): 181-186, 2020.
Article in English | WPRIM | ID: wpr-985102

ABSTRACT

Objective To study the mechanism of rib fracture caused by landing on different parts of the trunk using finite element method, and to provide some new techniques and new ideas for the reconstruction of the whole process of falls from height. Methods The finite element method was used to study the rib fracture of human security model THUMS4.0 caused by landing on different parts of the trunk. Then the model was compared with actual cases and the mechanism of rib fracture caused by falls from height was analyzed from a biomechanical point of view. Results There were some differences in the stress and strain distribution as well as the rib fracture sites when different parts touched the ground. Ribs on both sides of the body were fractured when the front of the trunk touched the ground, and the fractures were mainly located in the junction of the ribs and costal cartilage and the midaxillary line area. When the right anterior part of the trunk touched the ground, rib fracture occurred first on the side that touched the ground, and rib fractures were mainly located in the area from the right midaxillary line to the posterior axillary line, and junction of ribs on both sides and costal cartilage. When the back of the trunk touched the ground, the fracture sites were mainly located on the back of the ribs on both sides. When the right posterior part of the trunk touched the ground, multiple rib fractures were likely to occur in the parts that touched the ground. The plastic strains were mainly concentrated at the fracture sites, while the von Mises stresses were not only concentrated at the fracture sites, but also at other sites. Conclusion There are some differences in rib fracture location sites and injury mechanisms when different parts of the trunk touch the ground.


Subject(s)
Humans , Accidental Falls , Biomechanical Phenomena , Finite Element Analysis , Rib Fractures/etiology , Ribs , Torso
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