BACKGROUND:BioFlex system as a new pedicle screw fixation of dynamic stabilization device has less been reported concerning its biomechanics.
OBJECTIVE:To study the effect of BioFlex system fixation at different decompression ranges on disc stress at adjacent segments.
METHODS:Eight samples of fresh calf spines were used. Under physiologic axial loads (500, 900, 2 300 N), electronic universal testing machine was used to simulate the lumbar spine at three physiological states (standing, sitting and bending, standing on a portable 20 kg weight and bending). Progressive decompression modeling for each specimen and dividing into five groups:(1) complete status group;(2) complete status+BioFlex group;(3) partial laminectomy+BioFlex group;(4) 1/2 medial facetectomy+BioFlex group;(5) total facetectomy+BioFlex group. Strain gauges were used to record the stress of disc annulus. Electronic universal testing machine was used to record load-displacement curve and calculate stiffness.
RESULTS AND CONCLUSION:(1) The stress of the adjacent segment of the intervertebral disc increased with the expansion of the range of decompression. Compared with the complete status, stress obviously increased after BioFlex fixation, showing significant differences (P<0.05). The stress was significantly increased in the 1/2 medial facetectomy+BioFlex group compared with the partial laminectomy+BioFlex group (P<0.05). However, no significant difference was detected between the partial laminectomy+BioFlex group and complete status+BioFlex group, and between total facetectomy+BioFlex group and 1/2 medial facetectomy+BioFlex group (P>0.05). (2) Axial stiffness reduced with the expansion of the range of decompression. Compared with the complete status, axial stiffness noticeably increased after BioFlex fixation. The difference was not significant among four kinds of reconstruction structures. (3) These findings confirmed that after BioFlex fixation, with the expansion of the range of decompression, the stress of adjacent segments of intervertebral disc gradual y increased, but different ranges of decompression cannot affect the stiffness of reconstruction structure.

Objective To investigate the relevant factors of neonatal ventilator-associated pneumonia(VAP),and to provide a theoretical basis of prevention and treatment.Methods Retrospective analyed the clinical data of 145 critically ill neonates,who were treated with mechanical ventilator from Jan 2006 to Dec 2009 in the Third People′s Hospital of Wenzhou City,NICU.According to whether the neonates were occurred VAP,they were divided into two groups:VAP group(52 cases) and without VAP group(93 cases).Results Fifty-two out of the 145 neonates developed VAP.The incidence of VAP was 35.86%,the main relevent factors were the gestational ages,birth weights,the duration of mechanical ventilation and the times of intubation.There was significant difference between the two groups (P<0.05).The main pathogens were opportunistic bacteria,and mostly were G-bacilli.Conclusion The incidence of VAP has a close conclusion with the gestational ages,the birth weights,the duration of mechanical ventilation and the times of intubation.Regulate the use of breathing machine,strengthen aseptic operation,and select effective antibiotic can control the occurrence and development of VAP.

BACKGROUND:Photoelectric navigation-aided percutaneous pedicle screw placement has been developed extensively,but its accuracy,safety and effectiveness have not yet been confirmed by evidence-based medicine.OBJECTIVE:To compare the curative efficacy of photoelectric navigation-aided percutaneous pedicle screw placement and traditional open posterior pedicle screw fixation for thoracolumbar fractures.METHODS:Sixty patients with thoracolumbar fractures were equivalently randomized to treatment and control groups and then underwent photoelectric navigation-aided percutaneous pedicle screw placement and traditional open posterior pedicle screw fixation,respectively.The perioperative indexes,imaging indexes,function recovery and incidence of complications were compared between two groups.RESULTS AND CONCLUSION:(1) The Visual Analogue Scale scores,intraoperative blood loss,radiant times,and hospitalization time in the treatment group were significantly less than those in the control group (P ＜ 0.05).(2) The operation time did not differ significantly between two groups (P ＞ 0.05).(3) The postoperative sagittal Cobb angle,and percentage of anterior height in the vertebral body in the two groups were significantly improved compared with those before surgery (P ＜ 0.05),but all above imaging indexes showed no significant differences between two groups (P ＞ 0.05).The endplate-screw angle in the treatment group was significantly less than that in the control group (P ＜ 0.05).(5) The excellent and good rate of placement in the treatment group was significantly higher than that in the control group (P ＜ 0.05).(6) These results suggest that compared with the traditional open posterior pedicle screw fixation,the photoelectric navigation-aided percutaneous pedicle screw placement exhibits high placement accuracy,less radiant times,less trauma,less blood loss and rapid functional recovery.

Objective Clinical effect analysis of low dose dopamine(LDD)and dobutamine (DOB)subsidiary in the treatment of 86 cases of Children serious pneumonia.Methods From July 2011 to July 2013,86 CSP patients who were diagnosed with CSP in People's Hospital of Wenzhou were selected.Patientas were randomly divided into observation group(n=43)and control group(n=43)according to the random number method.Both groups were treated with routine treatment,then observation group on the basis with LDD and DOB subsidiary,then compared efficacy of two groups at 1 week after treatment,as well as the time of symptoms and signs which had improvements,and changes of levels of Interleukin-6(IL-6),Interleukin-8(IL-8), C-reactive protein(CRP)and Tumor necrosis factor-α(TNF-α)before and after treatment. Results The efficacy in observation group was significantly better than that of control group(P<0.05 ).And time of symptoms and signs which had improvement in the observation group was significantly less than control group(P<0.05).After treatment,IL-6,IL-8,CRP and TNF-αlevels were lower than before,but the observation group had a greater degree of reducing(P<0.05).Conclusion Routine treatment combined with LDD and DOB for CSP patients,can significantly improve the therapeutic effect,and relieve the clinical symptoms.

ObjectiveTo compare the therapeutic effects of percutaneous cervical discectomy (PCD group),percutaneous cervical disc nucleoplasty(PCN) and the association of them (PCDN) for the treatment of cervical intervertebral disk displacement and instability of cervical vertebral column.Methods From February 2003 to April 2011,171 consecutive patients with cervical disc herniation have presented at the authors' hospital and were retrospectively studied.The average age of patients was 47.8 years(ranged,21-74).Ninety-seven cases were treated with PCD,50 cases with PCN,and the other 24 cases with PCDN.Clinical result and the stability of cervical vertebral column after operation were evaluated and compared among the 3 groups.ResultsAll cases had been followed up for a median of 4.1 years.There was significant difference in the pre- and post-operation the Japanese Orthopaedic Association(JOA) scoring system on within 3groups (PCD:t=21.85,P＜0.05; PCN:t=14.50,P＜0.05; PCDN:t=8.56,P＜0.05).All cases had been successfully operated.There was no significant difference between groups among the 3 groups in terms of the clinical outcomes(The recovery rate of JOA standard evaluation,F=2.19,P=0.12).According to Odom criteria,the excellent and good rate are as follows:81.35％ in PCD,82.44％ in PCN,83.19％ in PCDN,respectively.There was no significant difference between groups among the 3 groups in terms of the clinical success rate (P＞0.05).There was no instability of cervical vertebral column cases in 3 groups after operation(P＞0.05),and no significant difference was found in terms of cervical vertebral column stability in pre- and post-operation in each group.ConclusionAll the three operations including PCN,PCD and PCDN are safe,minimally invasive spine surgery for the treatment of cervical intervertebral disk displacement; they achieve good clinical outcomes and there are no difference on the stability of cervical vertebral column between preoperation and postoperation.

OBJECTIVETo determine the genetic cause of an infant with multiple congenital anomalies.

METHODSRoutine karyotype analysis and chromosome microarray analysis (CMA) were carried out for the infant and her parents.

RESULTSCMA has detected a 9.3 Mb duplication at 9q34.11-q34.3. G-banding analysis suggested that the infant has a 46,XX,der(1)add(1)(p34.1) karyotype, while her father was 46, XY, t(1,9)(p36.3;q34.1). Fluorescence in situ hybridization (FISH) analysis confirmed that the 9q34 duplication has derived from the balanced translocation carried by the father.

CONCLUSIONA 9.3 Mb duplication was detected within the 9q34 region in an infant featuring multiple congenital anomalies. CMA and FISH have enabled detection of this duplication and facilitated genetic counseling and prevention of birth of further affected offspring.

BACKGROUND:Intertrochanteric fracture of femur often occurs in the elderly,and there will be a large amount of hidden blood loss after surgery.Reducing hidden blood loss can decrease complications and hospital stay. OBJECTIVE:To evaluate the effect of prolonged use of tranexamic acid on hidden blood loss after proximal femoral nail antirotation implantation in senile intertrochanteric fractures. METHODS:From January 2022 to May 2023,62 elderly admitted patients with intertrochanteric fracture of femur were selected from Zigong Fourth People's Hospital.All of them were treated with proximal femoral nail antirotation implantation after closed reduction on the traction bed.According to the use time of tranexamic acid,they were divided into two groups.In the control group(n=38),1 g tranexamic acid was given intravenically 15-30 minutes before incision,and 1 g was added 3 hours later.Based on the control group,the trial group(n=24)was given 1 g tranexamic acid intravenously once for 12 hours on the first day after surgery.Blood routine examinations were performed before surgery,on the day after surgery,and on the first,third and fifth days after surgery.Hemoglobin and hematocrit were counted.The theoretical total blood loss was calculated by Cross equation,and the incidence of complications in the two groups was recorded. RESULTS AND CONCLUSION:(1)Through statistical analysis,there was no significant difference in the amount of dominant blood loss between the two groups(P>0.05).(2)The number of grams of hemoglobin decreased,total blood loss and hidden blood loss in the trial group during perioperative period were lower than those in the control group,and the differences were statistically significant(P<0.05).(3)The hemoglobin values of the trial group on day 3 after surgery,and the hematocrit values on days 1 and 3 after surgery were higher than those of the control group,with statistical significance(P<0.05).(4)The hemoglobin and platelet count showed a downward trend after surgery,and the hemoglobin value was the lowest value on day 3,and the platelet value was the lowest value on day 1 after surgery,and then began to rise in both groups.(5)There was no significant difference in postoperative complications between the two groups(P>0.05).(6)The results show that prolonging use of tranatemic acid can effectively reduce the hidden blood loss in the treatment of femoral intertrochanteric fracture with proximal anti-rotation intramedullary nail,and does not increase the risk of complications.

Acid-base dissociation constant (pK_a) is a key physicochemical parameter in chemical science, especially in organic synthesis and drug discovery. Current methodologies for pK_a prediction still suffer from limited applicability domain and lack of chemical insight. Here we present MF-SuP-pK_a (multi-fidelity modeling with subgraph pooling for pK_a prediction), a novel pK_a prediction model that utilizes subgraph pooling, multi-fidelity learning and data augmentation. In our model, a knowledge-aware subgraph pooling strategy was designed to capture the local and global environments around the ionization sites for micro-pK_a prediction. To overcome the scarcity of accurate pK_a data, low-fidelity data (computational pK_a) was used to fit the high-fidelity data (experimental pK_a) through transfer learning. The final MF-SuP-pK_a model was constructed by pre-training on the augmented ChEMBL data set and fine-tuning on the DataWarrior data set. Extensive evaluation on the DataWarrior data set and three benchmark data sets shows that MF-SuP-pK_a achieves superior performances to the state-of-the-art pK_a prediction models while requires much less high-fidelity training data. Compared with Attentive FP, MF-SuP-pK_a achieves 23.83% and 20.12% improvement in terms of mean absolute error (MAE) on the acidic and basic sets, respectively.