Objective To explore the effect of the interrupted abdominal aorta compression after cardiopulmonary resuscitation (IAAC-CPR)on cardiopulmonary cerebral resuscitation in a rabbit model of cardiac arrest (CA). Methods According to the random number table,10 New Zealand rabbits of both genders were equally divided into the chest compression-cardiopulmonary resuscitation (CC-CPR) group or IAAC-CPR group ,with 5 rabbits in each group. CA model was reproduced by injection of iced-potassium chloride into the jugular vein and obstruction of trachea to produce asphyxia. CA was maintained for 3 minutes before cardiopulmonary resuscitation (CPR). CC-CPR was performed with assisted ventilation+chest compression,while IAAC-CPR was performed by the way of assisted ventilation + chest compressions + compressions on abdominal aorta. The hemodynamics and cerebral cortex blood flow were observed during resuscitation. Time of return of spontaneous circulation (ROSC),24-hour survival rates,and scores of neurological function,and situation of abdominal organs were recorded. Results At 30, 60,90 and 120 seconds after CPR,the cerebral blood flow (CBF,PU value)and mean arterial pressure(MAP, mmHg,1 mmHg=0.133 kPa)of IAAC-CPR group were significantly higher than those of CC-CPR group(CBF 30 seconds:16.1±6.0 vs. 7.8±2.2,60 seconds:91.6±11.8 vs. 57.3±23.2,90 seconds:259.9±74.9 vs. 163.6± 50.3,120 seconds:301.5 ±60.5 vs. 208.4 ±23.8;MAP 30 seconds:46.4 ±9.4 vs. 31.4 ±8.7,60 seconds:55.8 ± 13.8 vs. 34.0±11.5,90 seconds:61.2±11.5 vs. 38.2±10.1,120 seconds:63.6±11.8 vs. 40.2±10.2,all P<0.05). Compared with CC-CPR group,in IAAC - CPR group,the time necessary for ROSC was obviously shortened (seconds:182.0 ±59.0 vs. 312.6 ±86.6,t=2.787,P=0.024),24-hour nerve function score was significantly lowered(2.4±1.7 vs. 4.6±0.6,t=2.974,P=0.023). The successful recovery rate(80.0%vs. 60.0%,χ2=0.000, P =1.000)and 24-hour survival rate (80.0% vs. 40.0%,χ2=0.417,P =0.519)were significantly increased,but without statistical significance. No liver damage was found at 24 hours after ROSC. Conclusion In the early recovery of CA in rabbit,IAAC-CPR can result in better cerebral blood flow perfusion as compared with CC-CPR,and it significantly reduced damage to the nervous system function without producing abdominal organ damage.

Lycophytes and seed plants constitute the typical vascular plants. Lycophytes have been thought to have no paleo-polyploidization although the event is known to be critical for the fast expansion of seed plants. Here, genomic analyses including the homologous gene dot plot analysis detected multiple paleo-polyploidization events, with one occurring approximately 13-15 million years ago (MYA) and another about 125-142 MYA, during the evolution of the genome of Selaginella moellendorffii, a model lycophyte. In addition, comparative analysis of reconstructed ancestral genomes of lycophytes and angiosperms suggested that lycophytes were affected by more paleo-polyploidization events than seed plants. Results from the present genomic analyses indicate that paleo-polyploidization has contributed to the successful establishment of both lineages-lycophytes and seed plants-of vascular plants.
Evolution, Molecular ; Genome, Plant ; Genomics ; Phylogeny ; Polyploidy ; Selaginellaceae/genetics*