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find Author "ZHANG Nan" 11 results
  • Effects of Vitamin D Supplement on Blood Pressure: A Systematic Review

    Objective To systematically review the impact of vitamin D supplement on blood pressure, so as to provide a basis for clinical treatment. Methods Such databases as The Cochrane Library (Issue 8, 2011), MEDLINE (1996 to August 2011), EMbase (1974 to August 2011), CBM (1989 to 2011), CNKI (1997 to August 2011) and VIP (1989 to 2011) were searched to collect the randomized controlled trials (RCTs) about the impact of vitamin D supplement on blood pressure. Two reviewers independently screened the literature according to the inclusion criteria, extracted the data and assessed the quality. Then the meta-analysis was performed using RevMan 5.0 software. Results A total of 8 studies involving 907 participants were included. The methodological quality based on the improved Jadad scales displayed that, 7 studies scored 4 to 7 and only 1 study scored less than 4. The results of meta-analysis showed that compared with the placebo groups, vitamin D supplement had no significant difference in both systolic and diastolic blood pressure. Conclusion Based on current research evidences, compared with placebo, vitamin D supplement has no marked impact on either systolic or diastolic blood pressure. Due to the lack of studies, this conclusion still needs to be proved by conducting more well designed, large sample, and multicenter RCTs.

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  • Value of prognostic nutritional index for predicting 28-day death risk in intensive care unit patients after cardiopulmonary resuscitation

    Objective To investigate the relationship between the level of prognostic nutritional index (PNI) and 28-day mortality in patients after cardiopulmonary resuscitation. Methods A total of 955 patients admitted to intensive care unit after cardiopulmonary resuscitation between 2008 and 2019 were selected from the MIMIC-IV database and grouped according to the optimal cut-off value of PNI for retrospective cohort analysis. Primary outcome was defined as 28-day all-cause mortality. After adjusting for confounding factors by propensity score matching, the outcomes between high PNI and low PNI groups were compared. PNI and Sequential Organ Failure Assessment (SOFA) score were incorporated into a Cox proportional risk model to construct a predictive model, and the predictive effect was assessed using the concordance index, the net reclassification index, and the integrated discriminant improvement. Results After propensity score matching, compared with the high PNI group, the low PNI group had lower 28-day survival (P<0.001), higher doses of vasoactive drugs used during intensive care unit stay (P<0.001), higher SOFA score (P<0.001) and higher Logistic Organ Dysfunction System score (P=0.002). The admission PNI and SOFA score had similar predictive effects on 28-day mortality, with the area under the receiver operating characteristic curve of 0.639 and 0.638, respectively. In addition, compared with SOFA score alone, PNI combined with SOFA score improved the predictive performance, with an area under the curve of 0.673, the concordance index increasing from 0.598 to 0.622, and the net reclassification index and the integrated discriminant improvement estimates of 0.144 (P<0.001) and 0.027 (P<0.001), respectively. Conclusions PNI can be used as a new predictor of all-cause death risk within 28 days after cardiopulmonary resuscitation. SOFA score combined with PNI can improve the prediction effect.

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  • Investigation of the glucose dynamics with an approach of refined composite multi-scale entropy analysis

    The study on complexity of glucose fluctuation not only helps us understand the regulation of the glucose homeostasis system but also brings us a new insight of the research methodology on glucose regulation. In the experiments, we analyzed the complexity of the temporal structure of the 72 hours continuous glucose time series from a group of 93 subjects with type Ⅱ diabetes mellitus using the multi-scale entropy method. We adapted the most recently improved refined composite multi-scale entropy (RCMSE) algorithm which could overcome the shortcomings on the 72 hours short time series analysis. We then quantified and compared the complexity of continuous glucose time series between groups with type Ⅱ diabetes mellitus with different mean absolute glycemic excursion (MAGE) and glycated hemoglobin (HbA1c). The results implied that the complexity of glucose time series decreased on lower MAGE group compared to high MAGE group, and the entropy on scale 1 to 6 which corresponded to 5 to 30 min had significant differences between these two groups; the complexity of glucose time series decreased with the increasing HbA1c level but the entropy had no statistical difference among groups at different scales. Therefore, RCMSE provided us with a new prospect to analyze the glucose time series and it was proved that less complexity of glucose dynamics could indicate the impaired gluco-regulation function from the MAGE point of view or HbA1c for patients, and the glucose complexity had the potential to become a new biomarker to reflect the fluctuation of the glucose time series.

    Release date:2017-04-01 08:56 Export PDF Favorites Scan
  • Optimization of the pseudorandom input signals used for the forced oscillation technique

    The forced oscillation technique (FOT) is an active pulmonary function measurement technique that was applied to identify the mechanical properties of the respiratory system using external excitation signals. FOT commonly includes single frequency sine, pseudorandom and periodic impulse excitation signals. Aiming at preventing the time-domain amplitude overshoot that might exist in the acquisition of combined multi sinusoidal pseudorandom signals, this paper studied the phase optimization of pseudorandom signals. We tried two methods including the random phase combination and time-frequency domain swapping algorithm to solve this problem, and used the crest factor to estimate the effect of optimization. Furthermore, in order to make the pseudorandom signals met the requirement of the respiratory system identification in 4–40 Hz, we compensated the input signals’ amplitudes at the low frequency band (4–18 Hz) according to the frequency-response curve of the oscillation unit. Resuts showed that time-frequency domain swapping algorithm could effectively optimize the phase combination of pseudorandom signals. Moreover, when the amplitudes at low frequencies were compensated, the expected stimulus signals which met the performance requirements were obtained eventually.

    Release date:2017-10-23 02:15 Export PDF Favorites Scan
  • Open innovation of national infrastructure for translational medicine

    The Chinese government invested National Major Science and Technology Infrastructure for Translational Medicine (NITM) is a research platform with large-scale science facilities designed for opening and sharing. NITM is required to share its research facilities to domestic and international users and to facilitate interdisciplinary cooperation and innovation, it is also required to cooperate with other national major science and technology infrastructures so that these infrastructures can work together to enhance the nation’s international competitiveness in science and technology. This paper proposes to apply the concept of open innovation and designs an innovation model for the management of NITM.

    Release date:2018-12-24 02:03 Export PDF Favorites Scan
  • Efficacy and safety of dapagliflozin combined with hypoglycemic drugs for diabetes mellitus: a meta-analysis

    ObjectivesTo systematically review the efficacy and safety of dapagliflozin combined with hypoglycemic drugs in the treatment of diabetes patients.MethodsPubMed, The Cochrane Library, EMbase, WanFang Data, VIP, CNKI and CBM databases were electronically searched to collect randomized controlled trials (RCTs) on the efficacy and safety of dapagliflozin combined with hypoglycemic drugs in the treatment of diabetes patients from inception to December, 2018. Two reviewers independently screened literature, extracted data, and assessed the risk of bias of included studies. Then, meta-analysis was performed using RevMan 5.3 software and Stata 14.0 software.ResultsA total of 16 RCTs involving 5 388 patients were included. The results of meta-analysis showed that, compared with control group, intervention group provided more reduction in HbAlc (MD=−0.55, 95%CI −0.63 to −0.48, P<0.000 01) and body weight (MD=−2.17, 95%CI −2.46 to −1.88, P<0.000 01). There were no significant differences in hypoglycaemia (RR=1.05, 95%CI 0.93 to 1.18, P=0.44) and hypotension (RR=1.63, 95%CI 0.73 to 3.65, P=0.23). The incidence of urinary tract infection (RR=1.29, 95%CI 1.03 to 1.61, P=0.02) and genital infection (RR=3.89, 95%CI 2.86 to 5.29, P< 0.000 01) in intervention groups were higher than those in the control groups.ConclusionsCurrent evidence shows that dapagliflozin as an add-on drug to conventional antidiabetic drugs can more effectively reduce glycated hemoglobin and body weight in diabetic patients and does not increase the incidence of hypoglycemia and hypotension, however, with an increased risk for development of urinary tract infection and genital infections. Due to limited quality and quantity of the included studies, more high-quality studies are required to verify above conclusions.

    Release date:2020-01-14 05:25 Export PDF Favorites Scan
  • Effect and mechanism of glycyrrhizin on glial scar formation after spinal cord injury in rats

    ObjectiveTo explore the effect and potential mechanism of glycyrrhizin (GL) by inhibiting high mobility group box 1 (HMGB1) on glial scar formation after spinal cord injury (SCI) in rats.MethodsSeventy-two female Sprague Dawley rats were randomly divided into sham group (n=12), SCI model group (SCI group, n=36), GL intervention group (SCI+GL group, n=12), and nuclear factor κB (NF-κB) inhibitor [pynolidine dithiocarbamate (PDTC)] intervention group (SCI+PDTC group, n=12). The SCI models of SCI group, SCI+GL group, and SCI+PDTC group were made by modified Allen’s method, the sham group was only exposed the spinal cord without any injury. First of all, Basso-Beattie-Bresnahan (BBB) score of hind limbs and slope test were performed in SCI group at 1, 2, and 3 weeks after operation; Western blot was used to detect the expressions of glial fibrillary acidic protein (GFAP) and HMGB1 proteins. Compared with the sham group, the most significant time point in the SCI group was selected for subsequent experiment, in which the most significant glial scar was formed. Then, behavioral tests (BBB score of hind limbs and slope test), histological observation of spinal cord tissue structure, Western blot detection of HMGB1, GFAP, and NF-κB proteins, and immunohistochemical staining observation of GFAP and chondroitin sulfate proteoglycan (CSPG) were used to explore the effect of GL on the formation of glial scar after SCI and its potential mechanism.ResultsThe BBB score and slope angle of the SCI group increased gradually with time, which were significantly lower than those of the sham group at each time point (P<0.05). Western blot detection showed that the relative expressions of HMGB1 and GFAP proteins in the SCI group at 1, 2, and 3 weeks after operation were significantly higher than those in sham group (P<0.05). The change was most obvious at 3 weeks after SCI, therefore the spinal cord tissue was selected for subsequent experiments at this time point. At 3 weeks after operation, compared with the SCI group, BBB score and slope angle of SCI+GL group significantly increased (P<0.05); the relative expressions of HMGB1, GFAP, and NF-κB proteins detected by Western blot and the expressions of GFAP and CSPG proteins detected by immunohistochemical staining significantly decreased (P<0.05); the disorder of spinal cord tissue by HE staining improved, inflammatory cell infiltration reduced, and glial scar formation decreased. At 3 weeks after operation, the expressions of NF-κB, GFAP, and CSPG proteins of the SCI+PDTC group significantly reduced when compared with the SCI group (P<0.05); and the expression of NF-κB protein significantly decreased and the expressions of GFAP and CSPG proteins significantly increased when compared with the SCI+GL group (P<0.05).ConclusionAfter SCI in rats, the application of GL to inhibit the expression of HMGB1 can reduce the expression of GFAP and CSPG in the injured spinal cord, then reduce the formation of glial scars and promote the recovery of motor function of the hind limbs, and GL may play a role in inhibiting glial scar through HMGB1/NF-κB pathway.

    Release date:2020-11-02 06:24 Export PDF Favorites Scan
  • Differential diagnosis of high altitude pulmonary edema and COVID-19 with computed tomography feature

    To investigate the computed tomography (CT) characteristics and differential diagnosis of high altitude pulmonary edema (HAPE) and COVID-19, CT findings of 52 cases of HAPE confirmed in Medical Station of Sanshili Barracks, PLA 950 Hospital from May 1, 2020 to May 30, 2020 were collected retrospectively. The size, number, location, distribution, density and morphology of the pulmonary lesions of these CT data were analyzed and compared with some already existed COVID-19 CT images which come from two files, “Radiological diagnosis of COVID-19: expert recommendation from the Chinese Society of Radiology (First edition)” and “A rapid advice guideline for the diagnosis and treatment of 2019 novel corona-virus (2019-nCoV) infected pneumonia (standard version)”. The simple or multiple ground-glass opacity (GGO) lesions are located both in the HAPE and COVID-19 at the early stage, but only the thickening of interlobular septa, called “crazy paving pattern” belongs to COVID-19. At the next period, some increased cloudy shadows are located in HAPE, while lesions of COVID-19 are more likely to develop parallel to the direction of the pleura, and some of the lesions show the bronchial inflation. At the most serious stage, both the shadows in HAPE and COVID-19 become white, but the lesions of HAPE in the right lung are more serious than that of left lung. In summary, some cloudy shadows are the feature of HAPE CT image, and “crazy paving pattern” and “pleural parallel sign” belong to the COVID-19 CT, which can be used for differential diagnosis.

    Release date:2021-02-08 06:54 Export PDF Favorites Scan
  • Effectiveness and Performance Evaluation of Medical Rescue during 2 Weeks after Lushan Earthquake

    Objective We evaluated effectiveness and performance of medical rescue after Lushan earthquake during 2 weeks, and enriched Wenchuan lessons to provide useful references for emergency medical rescue (EMR) after similar earthquake worldwide. Methods We collected and analyzed official information, public documents, news release, and relevant information from websites, and then we systematically reviewed and descriptively analyzed all included literature of EMR after earthquake (domestic and foreign). Results Learned from Wenchuan earthquake, EMR for Lushan earthquake were characterized as: a) Assess the situations of quake damage and injuries were scientifically assessed; human resources, funds and materials were reasonably distributed; and the EMR relied mainly on regional rescue power of Sichuan province. b) Patients’ with critical injuries were treated using “Four concentration treatment principles”, which resulted in a new medical record of zero death, 14 days after the earthquake. c) The experience of EMR after Lushan earthquake verified, enriched and improved lessons from Wenchuan, Yushu and Yiliang earthquake, which provided first-hand references of evidence-based decision making for earthquake EMR worldwide.

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  • In vivo study of a novel micro-arc oxidation coated magnesium-zinc-calcium alloy scaffold/autologous bone particles repairing critical size bone defect in rabbit

    ObjectiveTo evaluate the effect of a novel micro-arc oxidation (MAO) coated magnesium-zinc-calcium (Mg-Zn-Ca) alloy scaffold/autologous bone particles to repair critical size bone defect (CSD) in rabbit and explore the novel scaffold in vivo corrosion resistance and biocompatibility.MethodsSeventy-two New Zealand white rabbits were randomly divided into 3 groups (n=24), group A was uncoated Mg-Zn-Ca alloy scaffold group, group B was 10 μm MAO coated Mg-Zn-Ca alloy scaffold group, and group C was control group with only autologous bone graft. The animals were operated to obtain bilateral ulnar CSD (15 mm in length) models. The bone fragment was removed and minced into small particles and were filled into the scaffolds of groups A and B. Then, the scaffolds or autologous bone particles were replanted into the defects. The animals were sacrificed at 2, 4, 8, and 12 weeks after surgery (6 rabbits each group). The local subcutaneous pneumatosis was observed and recorded. The ulna defect healing was evaluated by X-ray image and Van Gieson staining. The X-ray images were assessed and scored by Lane-Sandhu criteria. The percentage of the lost volume of the scaffold (ΔV) and corrosion rate (CR) were calculated by the Micro-CT. The Mg2+ and Ca2+ concentrations were monitored during experiment and the rabbit liver, brain, kidney, and spleen were obtained to process HE staining at 12 weeks after surgery.ResultsThe local subcutaneous pneumatosis in group B was less than that in group A at 2, 4, and 8 weeks after surgery, showing significant differences between 2 groups at 2 and 4 weeks after surgery (P<0.05); and the local subcutaneous pneumatosis was significantly higher in group B than that in group A at 12 weeks after surgery (P<0.05). The X-ray result showed that the score of group C was significantly higher than those of groups A and B at 4 and 8 weeks after surgery (P<0.05), and the score of group B was significantly higher than that of group A at 8 weeks (P<0.05). At 12 weeks after surgery, the scores of groups B and C were significantly higher than that of group A (P<0.05). Meanwhile, the renew bone moulding of group B was better than that in group A at 12 weeks after surgery. Micro-CT showed that ΔV and CR in group B were significantly lower than those in group A (P<0.05). Van Gieson staining showed that group B had better biocompatibility and osteanagenesis than group A. The Mg2+ and Ca2+ concentrations in serum showed no significant difference between groups during experiments (P>0.05). And there was no obvious pathological changes in the liver, brain, kidney, and spleen of the 3 groups with HE staining at 12 weeks.ConclusionThe MAO coated Mg-Zn-Ca alloy scaffold/autologous bone particles could be used to repair CSD effectively. At the same time, 10 μm MAO coating can effectively improve the osteanagenesis, corrosion resistance, and biocompatibility of Mg-Zn-Ca alloy scaffold.

    Release date:2018-03-07 04:35 Export PDF Favorites Scan
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