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Objective To study the effect of an essential α,β-unsaturated aldehyde from cigarette smoke crotonal-dehyde on myocardial contractile function and intracellular Ca2+function in mice. Methods Hearts of from male C57BL/6 mice were digested by Langendorff to islate the cardiomyocytes. The cardiomyocytes of mice were then in-cubated with crotonaldehyde(1,10,25 and 50 μmol/L) for 6 h,and the control group was treated without croton-aldehyde,then they were evaluated including peak shortening(PS),maximal velocity of shortening/relengthening (±dL/dt),time-to-PS(TPS),time-to-90% relengthening(TR90),fura-2 fluorescence intensity(FFI),intracel-lular Ca2+decay and SERCA 45Ca2+uptake and the expression of Na+-Ca2+exchange were evaluated by Western blot analysis. Results Compared with the control group, the higher concentrations of the crotonaldehyde(25 and 50 μmol/L) groups significantly diminished the PS, ±dL/dt,ΔFFI,SERCA activity and Ca2+decay (P<0.05), as well as prolonged the TR90(P<0.05);however the crotonaldehyde with different concentrations had no effect on the expression of Na+-Ca2+exchange in cardiomyocytes. Conclusions Crotonaldehyde may inhibit cardiomyocyte contraction by suppressing SERCA activity and compromising intracellular Ca2+handling.
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Objective To evaluate and compare the primary clinical efficacy in high myopia patients undergoing implantable collamer lens (ICL) implantation or femtosecond laser-LASIK (FS-LASIK).Methods Totally 73 patients with myopia from August 2016 to March 2017 in our hospital were collected and divided into ICL group(35 patients with 69 eyes) who receiving ICL implantation and LASIK group (38 patients with 76 eyes) who underwent FS-LASIK.There was no significant difference in gender composition and age between the two groups (both P ＞ 0.05).In addition,there was no significant difference in contrast sensitivity function (CSF) and glare CSF (GCSF) between the two groups before operation (both P ＞ 0.05).After 6 months of follow-up,the patient's uncorrected visual acuity,best corrected visual acuity and equivalent spherical degree were detected,and efficacy index and safety index were calculated.Meanwhile,CSF and GCSF examination were performed,followed by the observation of the occurrence of complications.Results There was no significant difference in the uncorrected visual acuity and best corrected visual acuity between the two groups before surgery (all P ＞ 0.05).The preoperative spherical equivalent in the ICL group was -4.000 to-12.00 (-8.86 ±3.70)D,and-4.00 to-11.75 (-8.51 ±4.20)D in the LASIK group,with no statistically significant difference (P ＞ 0.05).There was no significant difference in the uncorrected visual acuity,best corrected visual acuity and spherical equivalent between the two groups after surgery (all P ＞ 0.05).The efficacy coefficient and safety index of the ICL group were better than those in the LASIK group after 6 months,and the differences were statistically significant (all P ＜ 0.05).The CSF in the ICL group was at 1.5 c · d-1,3.0 c · d-1,6.0 c · d 1,12.0 c · d-1,and 18.0 c · d-1 after surgery,which was superior to the LASIK group,and the differences were statistically significant (all P ＜ 0.05).The GCSF in the ICL group was at 1.5 c · d-1,3.0 c · d-1,6.0 c · d-1 and 18.0 c · d-1 after surgery,which was superior to the LASIK group,and the differences were statistically significant (all P ＜ 0.05).Four hours after operation,there were 4 patients (7 eyes) with increased intraocular pressure,which were controlled by anterior chamber puncture,but no lens opacity presented.Conclusion Both ICL and FS-LASIK can effectively correct moderateto highmyopia,but ICL is better than FS-LASIK at the effectiveness index,the safety index,CSF and GCSF.
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Objective To simulate the process of lumbar burst fracture by finite element method, and investigate stress distributions on the cancellous bone of lumbar vertebrae under axial compressive loads. Methods The 3D finite element model of normal human thoracolumbar motion segments (T12-L2) was established. Stress at different levels (0.4, 0.6, 0.8, 1.0, 1.2 kN) was applied on the surface of T12 thoracic vertebra to simulate the different axial compressive loads at the occurrence of lumbar burst fracture. The ligature between concave vertexes of the inferior and superior endplates was divided into 7 portions, and the cancellous bone of the L1 vertebra was then divided into 7 layers with each layer separated into 6 statistic zones. The average stress on 18 statistic zones at 3 layers (Layer 1, 4, 7) of the cancellous bone was calculated, respectively. The average stress on 3 layers under the same loads was analyzed by one-way ANOVA, and stress distribution on the cancellous bone of lumbar vertebrae under different loads was also analyzed. ResultsUnder axial loads at 5 different levels, the average stress on Layer 1 and Layer 7 had obvious statistical significance compared with that on Layer 4(P0.05). The stress on the middle layer (Layer 4) was the minimum compared with that on Layer 1 and Layer 7. Conclusions Under axial compressive loads, the stress concentration occurred in the cancellous bone of lumbar vertebrae. The stress at adjacent vertebral endplates (inferior and superior endplates) was larger, while the stress on the middle layer was relatively smaller. The phenomenon that vertebral stress concentrating on inferior and superior endplates was consistent with the biomechanical mechanism of broken endplates caused by lumbar burst fracture, which indicates that the damage to lumbar structure may be related to the stress concentration on lumbar vertebrae.
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Differentiated thyroid cancer is a common endocrine malignancy, and its incidence has increased rapidly in the past 10 years.Although most patients have a good prognosis when treated with traditional methods, it is difficult to achieve satisfactory results for a small part of refractory thyroid cancer. With the understanding of the pathogenesis of thyroid cancer gradually improving to the molecular level, targeting therapy based on mechanisms and molecular targets have become a frontier area in the treatment of refractory thyroid cancer. Up to now,a variety of molecular targets has been found to be closely related to the incidence of thyroid cancer, and their effectiveness and safety has been verified by clinical trials. A number of targeted drugs of refractory thyroid cancer have been found through a method of target-based drug design, and have come into clinical trials or clinical applications. The representative drugs, sorafenib and lenvatinib, were approved for the treatment of refractory differentiated thyroid cancer, which provides a new hope for the treatment of advanced thyroid cancer.