In vitro and in vivo antitumor effects of acetylshikonin isolated from Arnebia euchroma (Royle) Johnst (Ruanzicao) cell suspension cultures

<p>Abstract</p> <p>Background</p> <p>Shikonin derivatives have cytotoxic and antitumor effects. This study aims to investigate the antitumor effects of acetylshikonin isolated from a Chinese medicinal herb <it>Arnebia euchroma (Royle) Johnst</it>.</p> <p>Methods</p> <p>The 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to determine the <it>in vitro </it>antitumor effects of acetylshikonin on human lung adenocarcinoma cell line A549, human hepatocellular carcinoma cell line Bel-7402, human breast adenocarcinoma cell line MCF-7 and mouse Lewis lung carcinoma (LLC) cell line. C₅₇BL/6 mice with LLC model were used to study the <it>in vivo </it>antitumor effects of acetylshikonin. The expression of bax, bcl-2 and caspase-3 proteins in LLC tissue was determined with immunohistochemical staining.</p> <p>Results</p> <p>In A549, Bel-7402, MCF-7 and LLC cell lines, acetylshikonin inhibited cell growth in a dose-dependent manner. IC50 (means ± SD) were 5.6 ± 0.86 μg/ml, 6.82 ± 1.5 μg/ml, 3.04 ± 0.44 μg/ml and 2.72 ± 0.38 μg/ml respectively. Acetylshikonin suppressed tumor growth in C57BL/6 mice with LLC. The inhibition rate of acetylshikonin (2 mg/kg) was 42.85%. Immunohistochemical staining revealed that in the acetylshikonin groups the expression of bax and caspase-3 increased, whereas the expression of bcl-2 decreased, suggesting that acetylshikonin induced tumor cell apoptosis through activating the pro-apoptotic bcl-2 family and caspase-3.</p> <p>Conclusion</p> <p>Acetylshikonin isolated from <it>Arnebia euchroma (Royle) Johnst </it>cell suspension cultures exhibits specific <it>in vivo </it>and <it>in vitro </it>antitumor effects.</p

An improve RCB method based on microwave induced thermo acoustic tomography

Thermoacoustic imaging (TAI) is a non-ionizing and non-invasive imaging method, which combines the merits of high ultrasound imaging resolution with high microwave imaging contrast. In TAI, a short non-ionizing microwave pulse irradiates tissues to induce a small temperature rise, which consequently causes thermoelastic expansion to generate TA signals. By using an image reconstruction algorithm, TAI can then recover the microwave absorption distribution inside the tissue and further distinguish abnormal areas from background normal tissues. TAI for breast cancer detection is the main purpose of this study, the basic theory of TAI was introduced at first, especially the RCB reconstruction algorithm for TAI. After that, in this dissertation, two sets of thermoacoustic imaging systems were developed, which named thermoacoustic tomography and ultra-short pulse based high resolution TAI. According to experiments and theoretical studies carried out in this dissertation, the feasibility of thermoacoustic imaging method by Robust Capon Beam-former (RCB) for breast cancer detection before its clinical investigation is fully validated. Due to high imaging performance needs for the early detection of breast cancer. Based on the advantages of TAI, the potential applications of TAI for finger joints and brain diseases diagnosing are explored, which is opening up a new field for TAI

Effects of contusion load on cervical spinal cord:A finite element study

Injury of cervical spine is a common injury of locomotor system usually accompanied by spinal cord injury, however the injury mechanism of contusion load to the spinal cord is not clear. This study aims to investigate its injury mechanism associated with the contusion load, with different extents of spinal cord compression. A finite element model of cervical spinal cord was established and two scenarios of contusion injury loading conditions, i.e. back-to-front and front-to-back loads, were adopted. Four different compression displacements were applied to the middle section of the cervical spinal cord. The distributions of von Mises stress in middle transverse cross section were obtained from the finite element analysis. For the back-to-front loading scenario, the stress concentration was found in the area at and near the central canal and the damage may lead to the central canal syndrome from biomechanical point of view. With the front-to-back load, the maximum von Mises stress located in central canal area of gray matter when subject to 10% compression, whilst it appeared at the anterior horn when the compression increased. For the white matter, the maximum von Mises stress appeared in the area of the anterior funiculus. This leads to complicated symptoms given rise by damage to multiple locations in the cervical spinal cord. The illustrative results demonstrated the need of considering different loading scenarios in understanding the damage mechanisms of the cervical spinal cord, particularly when the loading conditions were given rise by different pathophysiological causes

Inflammatory Links Between High Fat Diets and Diseases

In recent years, chronic overnutrition, such as consumption of a high-fat diet (HFD), has been increasingly viewed as a significant modifiable risk factor for diseases such as diabetes and certain types of cancer. However, the mechanisms by which HFDs exert adverse effects on human health remains poorly understood. Here, this paper will review the recent scientific literature about HFD-induced inflammation and subsequent development of diseases and cancer, with an emphasis on mechanisms involved. Given the expanding global epidemic of excessive HFD intake, understanding the impacts of a HFD on these medical conditions, gaining great insights into possible underlying mechanisms, and developing effective therapeutic strategies are of great importance

Superior Facet Joint Violations during Single Level Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Preliminary Retrospective Clinical Study

Background: Facet joint violation (FV) was reported as variable iatrogenic damage that can be a crucial risk factor leading to the adjacent segment degeneration (ASD). “Blind” screw placement technique in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) contributes to the increasing incidence of FV that can be influenced by several potential factors. Many controversies about these factors and clinical outcomes of different types of FV patients exist, yet they have not been analyzed. Methods 99 cases undergoing single-segment MIS-TLIF from July 2013 to December 2015 were retrospectively analyzed. Computed tomography (CT) was applied to determine the incidence of FV, and then the correlation between FV and relevant factors, including gender, age, body mass index (BMI), top-screw level, and decompression, was analyzed. A total of 53 cases were followed up after one year, 31 cases in noninjury (A group) and 22 patients in FV injury (B group). Results The incidence of FV was 39. 39% (39/99) in the patients and 23.23% (46/198) in the screws. Logistic regression analysis showed that screw at L5 in patients with BMI > 30 kg/m2 was vulnerable to FV (P < 0.05). Moreover, postoperative average intervertebral disc height (AIDH) of fusion segment, visual analog scale (VAS), and Oswestry disability index (ODI) scores improved significantly in group A and B when compared with preoperative data (P < 0.05). Adjacent superior average intervertebral disc height (ASAIDH) presented decrease, but adjacent superior intervertebral disc Cobb angle (ASIDCA) appeared to increase in the two groups at the final follow-up compared with postoperative 3 days (P < 0.05). Low back VAS and ODI scores in group A (31 cases) were lower than those in group B (22 cases) in the final follow-up (P < 0.05). Conclusion MIS-TLIF is an effective treatment for lumbar degenerative disease, but FV occurred at a higher incidence. Facet joints should be protected in MIS-TLIF to avoid FV

Quantum disorder in the two-dimensional pyrochlore Heisenberg antiferromagnet

We present the results of an exact diagonalization study of the spin-1/2 Heisenberg antiferromagnet on a two-dimensional version of the pyrochlore lattice, also known as the square lattice with crossings or the checkerboard lattice. Examining the low energy spectra for systems of up to 24 spins, we find that all clusters studied have non-degenerate ground states with total spin zero, and big energy gaps to states with higher total spin. We also find a large number of non-magnetic excitations at energies within this spin gap. Spin-spin and spin-Peierls correlation functions appear to be short-ranged, and we suggest that the ground state is a spin liquid.Comment: 7 pages, 11 figures, RevTeX minor changes made, Figure 6 correcte