Objective To investigate the biological effect of 50 Hz sinusoidal electromagnetic fields at 1 mT on the proliferation of the human osteosarcoma cell line MG-63.Methods Osteosarcrma MG-63 cells were divided into control and experimental groups.The control group was incubated without an electromagnetic field; the experimental group was incubated in a 50 Hz,1.0 mT sinusoidal electromagnetic field.On the 2nd,4th and 6th day,their proliferation was determined using a cell counting kit-8(CCK-8)assay.Variations in the cell cycle were detected with flow cytometry(FCM).Semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR)was used to measure cyclin B1 and cyclin D1 mRNA.Results Compared with the control group,proliferation of the experimental group cells was reduced significantly.The percentage of cells at G0-G1 phase increased,and the mRNA expression of cyclin B1 and cyclin D1 was significantly reduced.Conclusions A 50 Hz sinusoidal electromagnetic field at 1.0 mT can inhibit the proliferation of osteosarcoma cell line MG-63 significantly.

Objective To explore in vitro the best time window for using sinusoidal electromagnetic fields to promote the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs).Methods BMSCs were isolated and cultured from 4-week-old Sprague-Dawley rats (male and female,80-120g).The BMSCs (from passage 3) were exposed 0,1,4 or 8h/d for 7d,14,or 28d,respectively,to 15Hz sinusoidal electromagnetic fields with a maximum amplitude of lmT.Those exposed 0h/d served as the control.The relative expressions of runt related gene-2 (RUNX2),bone sialoprotein (BSP) and osteopontin (OPN) were determined using real-time,quantitative reverse transcription-polymerase chain reactions (RT-PCRs).The level of RUNX2 protein was determined by Western blotting after 14d.Alizarin red staining was used to compare calcium distribution in each group.Results Obvious promotion of differentiation to osteoblasts was observed after 7 days of exposure to the15 Hz sinusoidal electromagnetic fields,most obviously manifested by an outstanding increase of the early osteogenic index RUNX2 in those exposed 4h/d.After 14 days of intervention,the 1h/d exposure showed to be most effective,especially in inducing the changes of the late osteogenic index OPN.The trends of changes in RUNX2 protein were similar in all groups.After stimulating 1h/d for 14 and 28days,calcium deposition increased to the greatest extent.Conclusions Exposure to sinusoidal electromagnetic fields induces osteogenic differentiation to osteoblasts in rat BMSCs in vitro.There is an apparent window effect.The best results are observed with more days of exposure and shorter exposure time (1h) every day.

Objective To evaluate CT and MRI for the diagnosis of cranial extradural empyema.Methods The imaging features in 4 patients with cranial extradural empyema were analyzed.Results 2 cases in frontal,1 case in frontalparietal,1 case in posterier cranial fossa,in this series of 4 cranial extradural empyemas was found homogenous enhancement of dural,and thickened meninges surrounding the empyema.In the series of 1 case show bony thickening and thin.Conclusion The CT and MR of cranial extradural empyema can well demonstrate the morphological and pathological evidence of ivolved menings.Therefore,CT and MR is the most diagnostic value in cranial extradural empyema.

OBJECTIVETo investigate the changes in respiratory and circulatory functions in chronic obstructive pulmonary disease (COPD) patients during sequential invasive-noninvasive mechanical ventilation therapy, and evaluate the effects of this new technique.

METHODSTwelve COPD patients with type II respiratory failure due to severe pulmonary infection were ventilated through an endotracheal tube. When the pulmonary infection control window (PIC-Window) occurred, the patients were extubated and were ventilated with a facial mask using pressure support ventilation combined with positive end-expiratory pressure. The parameters of hemodynamics, oxygen dynamics, and esophageal pressure were measured at the PIC-Window during invasive mechanical ventilation, one hour after oxygen therapy via a naso-tube, and three hours after non-invasive mechanical ventilation.

RESULTSThe variation in esophageal pressure was 20.0 +/- 6 cmH(2)O during naso-tube oxygen therapy, and this variation was higher than that during non-invasive mechanical ventilation (10 +/- 6 cmH(2)O, P < 0.01). The changes in respiratory and circulatory parameters were not significantly different between invasive mechanical ventilation and noninvasive mechanical ventilation (P > 0.05).

CONCLUSIONSThe respiratory and circulatory functions of COPD patients remained stable during sequential invasive-noninvasive mechanical ventilation therapy using PIC-Window as a switch point for early extubation. The COPD patients can tolerated the transition from invasive mechanical ventilation to noninvasive mechanical ventilation.

Aged ; Blood Circulation ; physiology ; Female ; Humans ; Male ; Pulmonary Disease, Chronic Obstructive ; physiopathology ; therapy ; Respiration, Artificial ; methods ; Respiratory Physiological Phenomena

Objective　To investigate the effects of continuous tracheal gas insufflation (CTGI) combined with biphasic intermittent positive airway pressure (BIPAP) ventilation on dogs with spontaneous breathing. Methods　Eight canine models with oleic acid induced lung injury and spontaneous breathing were ventilated in a random order by Evita 2 (Drager Inc., Germany) in modes of BIPAP (BIPAP group) and BIPAP with CTGI flow rate of 3, 6 and 9?L/min (T3, T6 and T9 groups), respectively. The setting parameters of BIPAP were fiction of inspired oxygen 60%, inspiratory to expiratory ratio 1∶1, respiratory rate 20 and positive end expiratory pressure 5?cm?H2O. Arterial and mixed venous blood gas, lung mechanics, systemic and pulmonary hemodynamics status were monitored at the same level of PaCO2 obtained by adjusting peak inspiratory pressure of BIPAP. Results　Peak inspiratory pressure in the T6 group (14±4?cm?H2O) and in the T9 group (11±3?cm?H2O) were significantly lower than that of BIPAP (20±5?cm?H2O, P<0.01), but there was no significant difference among the T3, T6 and T9 groups or between the T3 and BIPAP groups. PaO2, mean artery blood pressure, mean pulmonary artery pressure, pulmonary artery wedge pressure, cardiac ouput, oxygen delivery and oxygen consumption all remained unchanged in four different conditions. Conclusions　Using BIPAP combined with CTGI does not cause asynchrony between ventilator and spontaneous breathing, but significantly decreases airway pressure with no influence on hemodynamics and oxygenation. Therefore, BIPAP with CTGI may be a useful support technique, especially in cases where the airway pressure should be limited.

OBJECTIVETo estimate the feasibility and the efficacy of early extubation and sequential non-invasive mechanical ventilation (MV) in chronic obstructive pulmonary disease (COPD) with exacerbated hypercapnic respiratory failure.

METHODSTwenty-two intubated COPD patients with severe hypercapnic respiratory failure due to pulmonary infection (pneumonia or purulent bronchitis) were involved in the study. At the time of pulmonary infection control window (PIC window) appeared, when pulmonary infection had been significantly controlled (resolution of fever and decrease in purulent sputum, radiographic infiltrations, and leukocytosis) after the antibiotic and the comprehensive therapy, the early extubation was conducted and followed by non-invasive MV via facial mask immediately in 11 cases (study group). Other 11 COPD cases with similar clinical characteristics who continuously received invasive MV after PIC window were recruited as control group.

RESULTSAll patients had similar clinical characteristics and gas exchange before treatment, as well as the initiating time and all indices at the time of the PIC window. For study group and control group, the duration of invasive MV was (7.1 +/- 2.9) vs (23.0 +/- 14.0) days, respectively, P < 0.01. The total duration of ventilatory support was (13 +/- 7) vs (23 +/- 14) days, respectively, P < 0.05. The incidence of ventilator associated pneumonia (VAP) were 0/11 vs 6/11, respectively, P < 0.01. The duration of intensive care unit (ICU) stay was (13 +/- 7) vs (26 +/- 14) days, respectively, P < 0.05.

CONCLUSIONSIn COPD patients requiring intubation and MV for pulmonary infection and hypercapnic respiratory failure, early extubation followed by non-invasive MV initiated at the point of PIC window significantly decreases the invasive and total durations of ventilatory support, the risk of VAP, and the duration of ICU stay.

Adult ; Aged ; Female ; Humans ; Hypercapnia ; therapy ; Male ; Middle Aged ; Pulmonary Disease, Chronic Obstructive ; complications ; Respiration, Artificial ; methods ; Respiratory Insufficiency ; therapy