Objective: To investigate the changes of myo cardial contractile function during myocardial stunning in calcium overload rats and the protective effects of tetrandrine. Methods: Forty-six rats were randomized into control, myocardial ischemia, myocardial stunning, low and high dose of tetrandrine groups. Another 10 rats were used to identify the calcium overload. vitamin D3 (0.3 million Unit/kg) and nicotinic acid were adm inistered. After 16 d when calcium overload occured, left anterior descending ar tery was ligated. Twenty minutes of myocardial ischemia followed by 60 min of re perfusion was induced. The contractile function parameters were determined dynam ically. At the end of experiment, myocardial cytosolic ［Ca2+］i was deter mined in various groups. In tetrandrine groups, tetrandrine (62.2 or 93.6 μmol/ kg ) was administered by gastrogavage daily.After 16 d, the rats undergone the e xperiments mentioned above. Results: Sixteen days after vitamin D3 , nicotinic acid were given, ［Ca2+］i increased by 2.6 folds (146.8±10.8 ) vs (368.5±22.6) nmol/L, (P<0.01). Whereas, ［Ca2+］i in tetrand rine groups were (210.8±16.4) and (198.6±15.3) nmol/L, which were significantl y lower than that of calcium overload group. Twenty minutes of myocardial ische mia resulted in the decrease of dp/dtmax and Vmax in all groups with the most si gnificant in stunning and calcium overload groups. The contractile function rest ored gradually after reperfusion. At all time points, dp/dtmax and Vmax in both tetrandrine groups were higher than those in both stunning and calcium overload groups. And effect with higher dose of tetrandrine were more significant than in low dose of tetrandrine. After 60 min of reperfusion, dp/dtmax in stunning, cal cium overload, low and high dose of tetrandrine groups were 49.7%, 51.5%, 71.0% and 83.4% of that in control, respectively， and Vmax were 55.0%, 49.8%, 73.9% and 77.5% of that in control, respectively. Conclusion: T he myocardial contractile function in vitamin D3-induced calcium overload gro up is impaired. On basis of myocardiocyte calcium overload, transient ischemia l eads to myocardial stunning. At the stage of ischemia, the impaired degree of my ocardial contractile function is similar to that in stunning group, suggesting a t this stage the effect of ischemia on myocardial function is greater than that of calcium overload. Tetrandrine chronically improves the myocardial function in Vitamin D3-induced calcium overload rats.

An improved and practical synthesis of racemic 11-demethylcalanolide A [(+/-)-1] was developed. This improved process involved Pechmann reaction on phloroglucinol with ethyl butyrylacetate to give 5,7,-dihydroxy4-n-propylcoumarin (3). Poly phosphoric acid (PPA) catalyzed acylation of compound (3) with crotonic acid, then intramolecular cyclization was achieved simultaneously in one step to afford the key intermediate chromanone (4). A microwave assisted synthetic method preparing chromene (6) using chromenynation of chromanone (4) with 1, 1-diethoxy-methyl-2-butene was conducted. Luche reduction of chromene (6) using NaBH4 with CeCl3 x 7H2O preferably gave (+/-)-1. The overall yield of this four step synthesis of (+/-)-1 was around 32% increasing one fold more than that of the previous method. An in vitro investigation showed that (+/-)-1 exhibited inhibitory activities against both wild-type and drug-resistant HIV-1 in HIV-1 RT and cell culture assay, and significant synergistic effects in combination with AZT, T-20, and indinavir. Its LD50 of acute toxicity in mice by intragastric administration and by intraperitoneal injection were 735.65 mg kg(-1) and 525.10 mg x kg(-1), respectively. The Cmax and AUC(0-infinity) were 0.54 microg x mL(-1) and 1.08 (microg x mL(-1) x h, respectively. The dynamics study of the inhibition of mice sera on HIV-1 RT showed that mice treated with 100 mg x kg(-1 (+/-)-1 once intraperitoneally were similar to that of 5 mg x kg(-1) of known clinical effective anti-HIV-1 drug neverapine. The results suggested that further investigation of the anti-HIV candidate (+/-)-1 was warranted.
Animals ; Anti-HIV Agents ; chemical synthesis ; immunology ; pharmacology ; toxicity ; Drug Synergism ; HIV Reverse Transcriptase ; metabolism ; HIV-1 ; drug effects ; enzymology ; Humans ; Immune Sera ; pharmacology ; Indinavir ; pharmacology ; Lethal Dose 50 ; Male ; Mice ; Pyranocoumarins ; chemical synthesis ; immunology ; pharmacology ; toxicity ; Reverse Transcriptase Inhibitors ; chemical synthesis ; immunology ; pharmacology ; toxicity ; Zidovudine ; pharmacology

OBJECTIVETo select the optimal pregnancy time window of embryonic pig skin precursor tissue for xenotransplantation and study its ability in wound repair.

METHODSSkin precursor tissues were obtained from pig fetus of fetal age of 35, 42, 56, 70 days, and were minced into microskin and transplanted to dorsal wounds of BALB/c nude mice, then they were covered with residual skin after plastic surgery of patients or adult pig skin (white). The characteristics of growth and development were observed after transplantation. Pathological examination was performed on 6 and 12 post operation weeks respectively to observe the tissue structure and tumorigenicity.

RESULTSSkin precursor tissues from fetal pig survived and developed after transplantation, and the microskin fused. New tissue area from skin precursor tissues with fetal age of 42 days was (47 +/- 6) mm2, which was higher than that of 35 days (18 +/- 8 mm2), 56 days (31 +/- 12 mm2), 70 days (20 +/- 8 mm2, P < 0.05). The skin precursor developed into "intact skin" with hair, sebaceous glands and sweat glands, and melanocytes were also detected in epidermis. The newly-grown skin tissue included epidermal and dermal layer, and obvious dermal papillae. Teratoma was not found after transplantation in skin precursor tissue with fetal age of 56, 70 days.

CONCLUSIONFetal pig skin precursor tissue with fetal age of 56 days can be used to repair wound as xenotransplantation.

Animals ; Fetal Tissue Transplantation ; Fetus ; Gestational Age ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Skin Transplantation ; Swine ; Transplantation, Heterologous ; Wound Healing

ObjectivesBased on the changes of lung lesions in patients with COVID-19 at different stages， a nomogram model describing CT image features was established by radiomics method to explore its efficacy in predicting the progression of the disease. MethodsThis retrospective study enrolled 136 patients with COVID-19 pneumonia who received at least two CTs including three cohorts （training cohort and validation cohort 1 and 2）. Patients in the training cohort were divided into three groups according to time between onset of fever symptoms and the first CT. The clinical manifestations and CT features of each group were analyzed and compared. A nomogram to predict disease progression was constructed according to the CT features of the patients， and its performance was evaluated. ResultsThe training cohort consisted of 41 patients.A nomogram was generated to predict disease progression based on three CT features： irregular strip shadow， air bronchial sign， and the proportion of lesions with irregular shape ≥50%. AUC（95%CI）=0.906（0.817，0.995）.The C index of the training cohort was 0.906， and the C index of the internal verification was 0.892. AUC（95%CI）of the validation cohort 1 （34 cases） =0.889（0.793，0.984）；AUC（95%CI）of the validation cohort 2 （61 cases）=0.876（0.706，1.000）.The calibration curves show that the predicted values of the nomogram are in good agreement with the observed values. ConclusionThe nomogram model based on CT radiomics can predict the outcome of lung lesions in patients with high sensitivity and specificity.According to the changes of CT image characteristics of patients with COVID-19， lung lesions will be improved when the proportion of irregular cable shadow， air bronchogram and irregular lesions is greater than 50%.