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.
Humans ; Computer Simulation ; Models, Biological ; Biomechanical Phenomena ; Finite Element Analysis ; Forensic Medicine

Aim To evaluate the effect of ZST93 on the proliferation in human chronic myeloid leukemia(CML)cells(K562)and explore the possible mechanism.Methods MTT assay, cell growth curve and inverted microscope were used to investigate the effect of ZST93 on proliferation of K562 cells.Cell transfection and Western blot were performed to detect the autophagy, while PI staining, Annexin V-FITC/PI and flow cytometry were conducted to determine cell apoptosis and its anticancer mechanism.Results ZST93 could significantly inhibit the proliferation of K562(IC50=2.59 μmol·L-1)and induce cell cycle arrest at G1-phase in a dose- and time-dependent manner.Also, through leading to accumulation of GFP-LC3, transition into LC3- II from LC3- 1 , and decrease of p62 expression, ZST93 induced autophagy initiation and autophagic flux.Furthermore, ZST93 induced extrinsic apoptotic pathway by activating caspase-8, and further promoted the cleavage of apoptosis related proteins including caspase-9, caspase-3 and PAR P.Moreover, Z-DEYD-FMK, the specific inhibitor of caspase-3 , could dramatically reduce the apoptosis induced by ZST93.Taken together, ZST93 could effec tively inhibit CML cells, arrest eell cycle at G,-phase, induce cell apoptosis anrl initiate autophagy.Conclusions The potential mechanism may he related to the regulation of autophagy intiation/caspase-8/caspase-3 signaling pathway, which provides a new idea and theoretical basis for the treatment of CML.

BACKGROUND: Delivery room resuscitation assists preterm infants, especially extremely preterm infants (EPI) and extremely low birth weight infants (ELBWI), in breathing support, while it potentially exerts a negative impact on the lungs and outcomes of preterm infants. This study aimed to assess delivery room resuscitation and discharge outcomes of EPI and ELBWI in China. METHODS: The clinical data of EPI (gestational age [GA] <28 weeks) and ELBWI (birth weight [BW] <1000 g), admitted within 72 h of birth in 33 neonatal intensive care units from five provinces and cities in North China between 2017 and 2018, were analyzed. The primary outcomes were delivery room resuscitation and risk factors for delivery room intubation (DRI). The secondary outcomes were survival rates, incidence of bronchopulmonary dysplasia (BPD), and risk factors for BPD. RESULTS: A cohort of 952 preterm infants were enrolled. The incidence of DRI, chest compressions, and administration of epinephrine was 55.9% (532/952), 12.5% (119/952), and 7.0% (67/952), respectively. Multivariate analysis revealed that the risk factors for DRI were GA <28 weeks (odds ratio [OR], 3.147; 95% confidence interval [CI], 2.082-4.755), BW <1000 g (OR, 2.240; 95% CI, 1.606-3.125), and antepartum infection (OR, 1.429; 95% CI, 1.044-1.956). The survival rate was 65.9% (627/952) and was dependent on GA. The rate of BPD was 29.3% (181/627). Multivariate analysis showed that the risk factors for BPD were male (OR, 1.603; 95% CI, 1.061-2.424), DRI (OR, 2.094; 95% CI, 1.328-3.303), respiratory distress syndrome exposed to ≥2 doses of pulmonary surfactants (PS; OR, 2.700; 95% CI, 1.679-4.343), and mechanical ventilation ≥7 days (OR, 4.358; 95% CI, 2.777-6.837). However, a larger BW (OR, 0.998; 95% CI, 0.996-0.999), antenatal steroid (OR, 0.577; 95% CI, 0.379-0.880), and PS use in the delivery room (OR, 0.273; 95% CI, 0.160-0.467) were preventive factors for BPD (all P < 0.05). CONCLUSION Improving delivery room resuscitation and management of respiratory complications are imperative during early management of the health of EPI and ELBWI.
Birth Weight ; Bronchopulmonary Dysplasia ; China/epidemiology* ; Delivery Rooms ; Female ; Gestational Age ; Humans ; Infant ; Infant, Extremely Low Birth Weight ; Infant, Extremely Premature ; Infant, Newborn ; Male ; Pregnancy

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.
Biomechanical Phenomena ; Craniocerebral Trauma/etiology* ; Finite Element Analysis ; Head ; Humans ; Skull ; Skull Fractures/etiology*

Background: Human infections with zoonotic coronaviruses (CoVs), including severe acute respiratory syndrome (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV, have raised great public health concern globally. Here, we report a novel bat-origin CoV causing severe and fatal pneumonia in humans. Methods: We collected clinical data and bronchoalveolar lavage (BAL) specimens from five patients with severe pneumonia from Jin Yin-tan Hospital, Wuhan, Hubei province, China. Nucleic acids of the BAL were extracted and subjected to next-generation sequencing. Virus isolation was carried out, and maximum-likelihood phylogenetic trees were constructed. Results: Five patients hospitalized from December 18 to December 29, 2019 presented with fever, cough, and dyspnea accompanied by complications of acute respiratory distress syndrome. Chest radiography revealed diffuse opacities and consolidation. One of these patients died. Sequence results revealed the presence of a previously unknown β-CoV strain in all five patients, with 99.8–99.9% nucleotide identities among the isolates. These isolates showed 79.0% nucleotide identity with the sequence of SARS-CoV (GenBank NC_004718) and 51.8% identity with the sequence of MERS-CoV (GenBank NC_019843). The virus is phylogenetically closest to a bat SARS-like CoV (SL-ZC45, GenBank MG772933) with 87.6–87.7% nucleotide identity, but is in a separate clade. Moreover, these viruses have a single intact open reading frame gene 8, as a further indicator of bat-origin CoVs. However, the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV, indicating that these viruses might use the same receptor. Conclusion: A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.

Objective::A multi-organ chip of intestine-liver-breast cancer was constructed based on microfluidic technology and used for pharmacokinetics-pharmacodynamics (PK-PD) study of drugs in vitro. Method::A multi-organ chip comprising a 4-layer polydimethylsiloxane (PDMS) substrate and a 2-layer poly(methyl methacrylate) (PMMA) cover was constructed by microfluidic technology. The connection between cells was investigated by staining the 21-day-grown human colon cancer cell line Caco-2 cell layer and the 3-day-grown human umbilical vein endothelial cell line HUVEC cell layer with CellTracker Red/Green and Hoechst, respectively. The transmission rates of 2 g·L^-1 fluorescein sodium and 33.28 mg·L^-1 propranolol acrossing the cell layer were employed to verify the function of the constructed intestinal module. The metabolic level of the liver module was investigated by comparing the inhibition rate of 125 μmol·L^-1 cyclophosphamide against human breast cancer cell line MCF-7 cells treated with human hepatoma cell line HepG2 cells in a conventional well plate and chip liver module for 48 h. The secretion of albumin by HepG2 cells in the chip was detected to verify the synthesis function of hepatic module. Caco-2 cell layer, HUVEC cell layer, HepG2 cell layer, MCF-7 cell layer and dialysis membrane were assembled on the chip, the culture medium containing 55 mg·L^-1 propranolol was injected into the upper channel of the chip for 4 h, and then changed into the normal culture solution. The mass concentration of propranolol in the lower circulating culture medium at each time point within 72 h was determined, and the drug-time curve was drawn. The culture medium containing 125 μmol·L^-1 cyclophosphamide, 5 μmol·L^-1 paclitaxel, 50 μmol·L^-1 capecitabine was injected into the circulating fluid in the upper layer of the chip, in order to study the inhibition rates of the three anti-tumor drugs on the MCF-7 cell layer on the chip within 72 h, and the results were compared with those of the 96-well plate. Result::The constructed chip performed well. The Caco-2 and HUVEC cell layers were tightly connected. The transmission of fluorescein sodium and propranolol between the cell layers demonstrated that the constructed intestinal module had good absorption and transport function. The inhibition rate of MCF-7 by 125 μmol·L^-1 cyclophosphamide after metabolism of HepG2 cells on the well plate was 22.12%, and the inhibition rate of MCF-7 by the unmetabolized cyclophosphamide was 1.84%. The inhibition rate of MCF-7 increased to 32.13%after injected 125 μmol·L^-1 cyclophosphamide from the upper layer of the chip liver module, and the inhibition rate of MCF-7 after injection from the lower layer of the chip liver module was 7.23%. The mass concentration of propranolol on the chip changed with time, which was basically consistent with that in vivo. The inhibition rate of MCF-7 on the plate with 125 μmol·L^-1 cyclophosphamide was lower than that on the chip, and the inhibition rates of MCF-7 on the plate with 5 μmol·L^-1 paclitaxel and 50 μmol·L^-1 capecitabine were higher than those on the chip. Conclusion::The constructed multi-organ chip of intestine-liver-breast cancer has the absorption and transport function of the intestine and the metabolic function of the liver. The chip can reflect the pharmacokinetic properties of propranolol in vivo, and can be used for pharmacodynamic studies of paclitaxel and capecitabine.