A high-performance room-temperature NH3 gas sensor based on WO3/TiO2 nanocrystals decorated with Pt NPs

In this work, a high-performance room-temperature ammonia (NH3) gas sensor based on Pt-modified WO3-TiO2 nanocrystals was synthesized via a two-step hydrothermal method. The structural properties were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The 10 at% Pt@WO3-TiO2 nanocrystals present the highest NH3 sensing performance at room temperature. Compared with the nanocrystals without Pt modification, the sensitivity of the Pt@WO3-TiO2 sensor is tenfold higher, with the lowest concentration threshold reaching the 75 ppb level. The response is approximately 92.28 to 50 ppm, and response and recovery times are 23 s and 8 s, respectively. The improved sensing was attributed to a synergetic mechanism involving the space charge layer effect and Pt metal sensitization, enhancing the electron transfer efficiency, oxygen vacancy and specific surface area. This study is expected to guide the development of high-performance room-temperature ammonia sensors for clinical breath testing.

Diagnostic performance of 3.0 T unenhanced Dixon water-fat separation coronary MR angiography in patients with low-to-intermediate risk of coronary artery disease

PURPOSE

To evaluate the diagnostic performance of 3.0 T unenhanced compressed-sensing sensitivity encoding (CS-SENSE) Dixon water-fat separation coronary MR angiography (CMRA) in patients with low-to-intermediate risk of coronary artery disease (CAD) and its ability to grade the severity of CAD based on Coronary Artery Disease Reporting and Data System (CAD-RADS).

METHODS

A total of 55 patients who was clinically evaluated as low-to-intermediate risk of CAD were finally included to undergo both 3.0 T CS-SENSE water-fat separation CMRA and coronary computed tomography angiography (CCTA), and 11 of them also underwent X-ray coronary angiography (CAG). The severity of coronary artery disease was graded in patients who had completed both CCTA and CMRA examinations by the use of CAD-RADS reports for the patients with stable chest pain, and the diagnostic consistency between the two approaches was evaluated. Diagnostic performance of CMRA was assessed using the combination of CCTA and CAG as the reference standard for excluding or confirming CAD respectively.

RESULTS

The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy of 3.0 T unenhanced water-fat separation coronary MRA were 90.0%, 95.0%, 81.8%, 97.4% and 94.0% for a patient-based analysis respectively. In comparison with CCTA, 3.0 T Dixon water-fat separation CMRA demonstrated excellent consistency in grading the severity of coronary heart disease according to CAD-RADS (0.77 for kappa value).

CONCLUSION

In the group of low-to-intermediate probability for CAD, 3.0 T unenhanced CS-SENSE Dixon water-fat separation CMRA can present satisfactory diagnostic performance for the exclusion of CAD with high sensitivity and negative predictive value as well as the evaluation of grading the severity of coronary artery disease.

[Clinical application of split liver transplantation: a single center report of 203 cases]

Objective: To investigate the safety and therapeutic effect of split liver transplantation (SLT) in clinical application. Methods: This is a retrospective case-series study. The clinical data of 203 consecutive SLT, 79 living donor liver transplantation (LDLT) and 1 298 whole liver transplantation (WLT) performed at the Third Affiliated Hospital of Sun Yat-sen University from July 2014 to July 2023 were retrospectively analyzed. Two hundred and three SLT liver grafts were obtained from 109 donors. One hundred and twenty-seven grafts were generated by in vitro splitting and 76 grafts were generated by in vivo splitting. There were 90 adult recipients and 113 pediatric recipients. According to time, SLT patients were divided into two groups: the early SLT group (40 cases, from July 2014 to December 2017) and the mature SLT technology group (163 cases, from January 2018 to July 2023). The survival of each group was analyzed and the main factors affecting the survival rate of SLT were analyzed. The Kaplan-Meier method and Log-rank test were used for survival analysis. Results: The cumulative survival rates at 1-, 3-, and 5-year were 74.58%, 71.47%, and 71.47% in the early SLT group, and 88.03%, 87.23%, and 87.23% in the mature SLT group, respectively. Survival rates in the mature SLT group were significantly higher than those in the early SLT group (χ2=5.560,P=0.018). The cumulative survival rates at 1-, 3- and 5-year were 93.41%, 93.41%, 89.95% in the LDLT group and 87.38%, 81.98%, 77.04% in the WLT group, respectively. There was no significant difference among the mature SLT group, the LDLT group and the WLT group (χ2=4.016, P=0.134). Abdominal hemorrhage, infection, primary liver graft nonfunction,and portal vein thrombosis were the main causes of early postoperative death. Conclusion: SLT can achieve results comparable to those of WLT and LDLT in mature technology liver transplant centers, but it needs to go through a certain time learning curve.

A clinical strategy to improve the diagnostic performance of 3T non-contrast coronary MRA and noninvasively evaluate coronary distensibility: combination of diastole and systole imaging

BACKGROUND

The clinical application of coronary MR angiography (MRA) combining diastole and systole imaging has never been described comprehensively in coronary artery disease (CAD) patients. We aimed to design an optimal non-contrast coronary MRA scan protocol combining diastolic and systolic imaging and to (1) evaluate its diagnostic performance for detecting significant coronary stenosis; (2) evaluate the feasibility of this protocol to noninvasively measure the coronary distensibility index (CDI).

METHODS

From June 2021 to May 2022, 33 healthy volunteers and 91 suspected CAD patients scheduled for X-ray coronary angiography (CAG) were prospectively enrolled. 3T non-contrast water-fat coronary MRA was carried out twice at diastole and systole. Significant coronary stenosis was defined as a luminal diameter reduction of ≥ 50% using CAG as the reference and was evaluated as follows: (1) by coronary MRA in diastole alone; (2) by coronary MRA in systole alone; (3) by combined coronary MRA in diastole and systole. According to CAG, the patients were divided into significant CAD patients and non-significant CAD patients. The difference in CDI among participants was evaluated.

RESULTS

Combined coronary MRA was completed in 31 volunteers and 76 patients. The per-patient sensitivity, specificity, and accuracy of combined coronary MRA were 97.5%, 83.3%, and 90.8%, respectively. Compared with single diastolic mode, combined coronary MRA showed equally high sensitivity but improved specificity on a per-patient basis (83.3% vs. 63.9%, adjusted P = 0.013). The CDI tested by coronary MRA decreased incrementally from healthy volunteers to non-significant and significant CAD patients.

CONCLUSION

Compared with single-phase mode, 3 T non-contrast combined coronary MRA significantly improved specificity and may have potential to be a simple noninvasive method to measure CDI.

[Safety and efficacy of yellow zebra guide wire exchange system in the treatment of complete upper digestive stenosis]

To investigate the efficacy and safety of yellow zebra guide wire exchange system in the treatment of complete upper digestive stenosis. To analyze the success rate and adverse events, a retrospective analysis was conducted on patients with complete digestive stenosis in Zhongda Hospital Affiliated to Southeast University from May 2019 to April 2023 and the First Affiliated Hospital of Nanjing Medical University from August 2011 to March 2015. A total of 41 patients were included, including 25 males and 16 females, aged (65±12) years (28-94 years). Among them, 40 patients were successfully inserted with yellow zebra guide wire and underwent endoscopic treatment using the outer tube replacement with hard steel wire, with 97.6% (40/41) effective rate. Eleven patients (27.5%) were accompanied by varying degrees of retrosternal pain, without complications such as bleeding or perforation.

[Characteristics of primary ocular symptoms in children with optic pathway glioma at different ages]

Objective: To investigate the characteristics of initial ocular symptoms in children with optic pathway glioma (OPG) at different age stages. Methods: A retrospective case series study was conducted. Clinical data of 16 children with OPG who were diagnosed and treated in the Department of Ophthalmology, Beijing Children's Hospital, Capital Medical University from April 2017 to July 2021 were collected. The initial ocular symptoms, clinical manifestations of the eyes and nervous system, imaging and histopathological features were analyzed, and the differences in initial ocular symptoms between infants and young children aged≤36 months and older children aged>36 months were compared. Results: Of all 16 children included, 9 were male and 7 were female. The onset age was 15.0 (6.3, 56.5) months, and the diagnosis age was 48.0 (11.3, 78.0) months. There were 11 infants and young children, and 5 older children. Eye symptoms were the initial manifestation in 11 cases, including 8 cases of infants and young children (5 cases presented with irregular nystagmus, 2 cases with strabismus, and 1 case with failure to chase visual target), and 3 cases of older children (2 cases presented with decreased vision and 1 case with optic disc edema). The imaging findings showed that optic chiasm-involved OPG accounted for the highest proportion, with 3 cases in older children and 8 cases in infants and young children. Among the 8 children with optic chiasm-involved OPG who underwent surgical treatment, 5 were diagnosed with pilocytic astrocytoma according to histopathological results. Seven children had useful vision saved after treatment, and 1 child had visual loss accompanied by cognitive impairment due to surgery after 4 years of nystagmus. Conclusion: OPG in children often manifests as initial ocular symptoms, with irregular nystagmus being more common in infants and young children, and vision loss being the main symptom in older children.

Comparison between Dual-Energy CT and Quantitative Susceptibility Mapping in Assessing Brain Iron Deposition in Parkinson Disease

BACKGROUND AND PURPOSE

Both dual-energy CT and quantitative susceptibility mapping can evaluate iron depositions in the brain. The purpose of this study was to compare these 2 techniques in evaluating brain iron depositions in Parkinson disease.

MATERIALS AND METHODS

Forty-one patients with Parkinson disease (Parkinson disease group) and 31 age- and sex-matched healthy controls (healthy control group) were included. All participants underwent brain dual-energy CT and quantitative susceptibility mapping. ROIs were set bilaterally in the globus pallidus, substantia nigra, red nucleus, caudate nucleus, and putamen. CT values and magnetic susceptibility values were obtained in each ROI. Differences in CT values and magnetic susceptibility values between the Parkinson disease and healthy control groups were compared, followed by analysis of receiver operating characteristic curves. Correlations between CT values and magnetic susceptibility values were then evaluated.

RESULTS

The CT values of the bilateral globus pallidus, substantia nigra, and red nucleus were higher in the Parkinson disease group (P < .05). The magnetic susceptibility values of the bilateral globus pallidus and substantia nigra were higher in the Parkinson disease group (P < .05). The CT value of the right globus pallidus in linear fusion images had the highest diagnostic performance (0.912). Magnetic susceptibility values of the bilateral globus pallidus in the Parkinson disease group were positively correlated with CT values at the level of 80 kV(peak), linear fusion images, and SN150 kV(p) (r = 0.466∼0.617; all, P < .05).

CONCLUSIONS

Both dual-energy CT and quantitative susceptibility mapping could assess excessive brain iron depositions in Parkinson disease, and we found a positive correlation between CT values and magnetic susceptibility values in the bilateral globus pallidus.

SnO2 mesoporous nanoparticle-based gas sensor for highly sensitive and low concentration formaldehyde detection

Indoor air quality detection, especially formaldehyde (HCHO) detection, is of great importance in practical application. A key limitation of promoting gas-sensing devices is the lack of sensing materials with high sensing sensitivity and selectivity. In this study, SnO₂ mesoporous nanoparticles are fabricated by a facile hydrothermal route with a subsequent acid etching process. The prepared samples show high response toward HCHO (133.5, 222.8 for 100 ppm and 200 ppm HCHO, respectively) and short response/recovery time (15/22 s at 10 ppm). The excellent HCHO sensing performance benefits from the comprehensive regulation of the depletion region width, surface area and rich porosity, which is effective for the promotion of surface adsorption and catalyst activity. It is expected that the excellent sensing properties are promising for practical HCHO gas detection.

[Analysis of clinical and imaging features of 6 cases of linear scleroderma en coup de sabre with central nervous system involvement in children]

Objective: To summarize the clinical and imaging features of linear scleroderma en coup de saber (LSCS) with central nervous system involvement in children. Methods: The clinical data(clinical manifestations and imaging features) of 6 children diagnosed with LSCS with central nervous system involvement who were admitted to Beijing Children's Hospital Affiliated to Capital Medical University from May 2019 to November 2021 were retrospectively analyzed. Results: The 6 patients were all female, aged 6.8 (3.3, 11.0) years at the time of diagnosis, and aged 3.0 (1.7, 4.1) years at the time of discovery of facial skin lesions. Facial skin lesions appeared before neurological symptoms in 5 cases, and neurological symptoms appeared 2 months before skin lesions in 1 case. All the patients had "sword wound" skin lesions on the forehead with alopecia. Neurological manifestations included epileptic seizures in 6 cases, focal neurological defects in 5 cases, and headaches in 2 cases. The intracranial lesions were all ipsilateral to the skin lesions. The magnetic resonance imaging (MRI) of 6 cases showed abnormal signals mainly involving white matter in 1 hemisphere, and 3 cases showed local encephalomalacia. The scattered low signal was observed in 5 cases on susceptibility weighted imaging. Localized brain parenchyma or leptomeninges enhancement was seen on Gadolinium-enhanced sequences in 5 cases. Scattered foci of calcification on the affected side were seen on cranial CT in 4 cases. Skin biopsy was performed in 2 cases. Part of the lesion of the brain was removed in 1 case, and the pathological findings suggested small vasculitis, which was consistent with skin pathological changes. All patients received symptomatic treatment with antiepileptic drugs. Oral prednisone combined with methotrexate was given in 4 cases, and 1 case was given oral prednisone only. One case was presumed to be in the resting stage of the disease due to significant cerebral atrophy in half of the brain, and only antiepileptic drugs were added. The patients were followed up for 6-36 months. The skin lesions of scleroderma and alopecia did not progress in 5 cases, and hemifacial atrophy was developed in 1 case, which was considered to be combined with Parry-Romberg syndrome. The seizures were controlled in 4 cases. One case had reduced seizure frequency but left hemiplegia. One patient still had intractable epilepsy and paroxysmal headache. Conclusions: LSCS with central nervous system involvement is more common in girls, with seizures and neurological defects as the main manifestations. Intracranial lesions are mostly ipsilateral to the skin lesions. Cerebral microbleeds, calcification, and encephalomalacia foci are common, and the pathological changes in skin and intracranial lesions are consistent with small-vessel vasculitis. Prednisone combined with methotrexate treatment has shown some efficacy, but some children remain with refractory epilepsy and neurological deficit symptoms.

Colonoscopy skills improvement training improves patient comfort during colonoscopy

INTRODUCTION

We aimed to assess the effect of Colonoscopy Skills Improvement (CSI) training on patient comfort and sedation-related complications during colonoscopy.

METHODS

This retrospective cohort study was performed on 19 endoscopists practicing in a Canadian tertiary care center who completed CSI training between October 2014 and May 2016. Data from 50 procedures immediately prior to, immediately after, and eight months following CSI training were included for each endoscopist. The primary outcome variable was intraprocedural comfort, and secondary outcomes included intraprocedural hypotension and hypoxia. Data were extracted from an electronic medical record and analyzed using SPSS version 20.0. Univariate analysis and stepwise multivariable logistic regression were performed to determine if there was an association between patient comfort and CSI training. Predictors of these outcomes including patient age, gender, sedation use and dosing, procedure completion, quality of bowel preparation, endoscopist experience, and specialty were included in the analysis.

RESULTS

2533 colonoscopies were included in the study. The mean dose of sedatives was reduced immediately following CSI training and at 8 months for both Fentanyl (75.4 mcg v. 67.8 mcg v. 65.9 mcg, p < 0.001) and Midazolam (2.57 mg v. 2.27 mg v. 2.19 mg, p < 0.001). The percentage of patients deemed to have a comfortable exam improved following endoscopist participation in CSI training and remained improved at 8 months (55.1% v. 70.2% v. 69.8%, p < 0.001). No significant change in rates of intraprocedural hypoxia or hypotension were noted following CSI training.

CONCLUSION

CSI training is associated with improved patient comfort and reduced sedation requirements during colonoscopy.

MDA5 attenuate autophagy in chicken embryo fibroblasts infected with IBDV

1. The role of melanoma differentiation-associated protein 5 (MDA5) in infectious bursal disease virus (IBDV)-induced autophagy was studied in chicken embryos.2. Chicken embryo fibroblasts (CEF) were used as the research model and small interfering RNA (siRNA), western blot, indirect enzyme-linked immunosorbent assay (ELISA), real-time fluorescence quantitative polymerase chain reaction (PCR) and transmission electron microscopy were used to detect autophagy, IBDV replication, CEF damage, and activation of both MDA5 and its signalling pathway.3. The results showed that CEF infected with IBDV activated the intracellular MDA5 signalling pathway and caused autophagy via inactivation of the AKT/mTOR pathway. While autophagy promotes IBDV proliferation, MDA5 weakens IBDV-induced CEF autophagy thus inhibiting IBDV replication and protecting CEF cells.4. The results indicated that chMDA5 can be activated by IBDV and attenuate CEF autophagy caused by IBDV infection, thereby inhibiting IBDV replication. This study provided a foundation for further exploring the relationship between viruses, autophagy and the pathogenic mechanism of the MDA5 pathway involved in IBDV.

Clinical Application of Non-Contrast-Enhanced Dixon Water-Fat Separation Compressed SENSE Whole-Heart Coronary MR Angiography at 3.0 T With and Without Nitroglycerin

BACKGROUND

3.0 T non-contrast-enhanced nitroglycerin (NTG)-assisted whole-heart coronary magnetic resonance angiography (MRA) employing Dixon water-fat separation and compressed SENSE (CS-SENSE) acceleration is a promising method for diagnosing coronary artery disease (CAD).

PURPOSE

To evaluate the diagnostic performance of this technique for detecting clinically-relevant (≥50% diameter reducing) CAD and to evaluate the difference in NTG-induced coronary vasodilation between patients with and without clinically-relevant CAD.

STUDY TYPE

Prospective.

POPULATION

Sixty-six patients with suspected CAD.

FIELD STRENGTH/SEQUENCE

3.0 T; CSSENSE, Dixon water-fat separation, three-dimensional segmented turbo field gradient-echo sequence for whole-heart coronary MRA.

ASSESSMENT

Overall image quality of coronary MRA was calculated on the basis of all visible coronary segments. The diagnostic performance of coronary MRA for detecting a ≥50% reduction in coronary artery diameter with and without NTG was compared using X-ray coronary angiography (CAG) as the reference. According to CAG, patients were divided into a non-clinically-relevant CAD group and clinically-relevant CAD group, and the difference in NTG-induced vasodilation between the groups was evaluated.

STATISTICAL TESTS

Unpaired/paired Student's t-test, Mann-Whitney U test, paired Wilcoxon signed-rank test, χ² test, McNemar test. A two-tailed P value <0.05 was considered significant.

RESULTS

Overall image quality was increased significantly in the coronary MRA images after NTG. The diagnostic performance of the non-NTG vs. NTG-assisted coronary MRA was as follows on a per-patient basis: sensitivity 94.3% vs. 94.3%, specificity 64.5% vs. 83.9%, positive predictive value 75.0% vs. 86.8%, negative predictive value 90.9% vs. 92.9%, and accuracy 80.3% vs. 89.4%, respectively. NTG-induced vasodilation was significantly lower in the clinically-relevant CAD group than in the non-clinically-relevant CAD group (13.7 ± 8.1% vs. 24.1 ± 16.3%).

DATA CONCLUSION

Non-contrast Dixon water-fat separation CS-SENSE coronary MRA at 3.0 T can noninvasively detect clinically-relevant CAD and sublingual NTG improved performance. Combining pre- and post-NTG coronary MRA may provide a simple noninvasive and nonionizing test to evaluate coronary vasodilation function.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY STAGE: 2.

Metabolic syndrome cannot mask the changes of faecal microbiota compositions caused by primary hepatocellular carcinoma

Both hepatocellular carcinoma (HCC) and metabolic syndrome are closely associated with the composition of the gut microbiota (GM). Although it has been proposed that elements of the GM can be used as biomarkers for the early diagnosis of HCC, whether metabolic syndrome results in a misrepresentation of the results of the early diagnosis of HCC using GM remains unclear. We compared the differences in the faecal microbiota of 10 patients with primary HCC, six patients with type 2 diabetes mellitus (T2DM), seven patients with arterial hypertension, six patients with both HCC and T2DM, and 10 patients with both HCC and arterial hypertension, as well as 10 healthy subjects, using high-throughput sequencing of 16S rRNA gene amplicons. Our results revealed a significant difference in the GM between subjects with and without HCC. The 49 bacterial genera out of the 494 detected genera were significantly different between the groups. These results show that changes in the GM can be used to distinguish between subjects with and without HCC, and can resist interference of T2DM and arterial hypertension with the GM. The results of the present study provide an important basis for the clinical auxiliary diagnosis of HCC by detecting the GM.

Utility of Contrast-Enhanced T2 FLAIR for Imaging Brain Metastases Using a Half-dose High-Relaxivity Contrast Agent

BACKGROUND AND PURPOSE

Efficient detection of metastases is important for patient' treatment. This prospective study was to explore the clinical value of contrast-enhanced T2 FLAIR in imaging brain metastases using half-dose gadobenate dimeglumine.

MATERIALS AND METHODS

In vitro signal intensity of various gadolinium concentrations was explored by spin-echo T1-weighted imaging and T2 FLAIR. Then, 46 patients with lung cancer underwent nonenhanced T2 FLAIR before administration of half-dose gadobenate dimeglumine and 3 consecutive contrast-enhanced T2 FLAIR sequences followed by 1 spin-echo T1WI after administration of half-dose gadobenate dimeglumine. After an additional dose of 0.05 mmol/kg, 3D brain volume imaging was performed. All brain metastases were classified as follows: solid-enhancing, ≥ 5 mm (group A); ring-enhancing, ≥ 5 mm (group B); and lesion diameter of <5 mm (group C). The contrast ratio of the lesions on 3 consecutive phases of contrast-enhanced T2 FLAIR was measured, and the percentage increase of contrast-enhanced T2 FLAIR among the 3 groups was compared.

RESULTS

In vitro, the maximal signal intensity was achieved in T2 FLAIR at one-eighth to one-half of the contrast concentration needed for maximal signal intensity in T1WI. In vivo, the mean contrast ratio values of metastases on contrast-enhanced T2 FLAIR for the 3 consecutive phases ranged from 63.64% to 83.05%. The percentage increase (PI) values of contrast-enhanced T2 FLAIR were as follows: PI_A < PI_B (P = .001) and PI_A < PI_C (P < .001). The degree of enhancement of brain metastases on contrast-enhanced T2 FLAIR was lower than on 3D brain volume imaging (P < .001) in group A, and higher than on 3D brain volume imaging (P < .001) in group C.

CONCLUSIONS

Small or ring-enhancing metastases can be better visualized on delayed contrast-enhanced T2 FLAIR using a half-dose high-relaxivity contrast agent.

Effects of astragalus polysaccharide on intestinal inflammatory damage in goslings infected with gosling plague

1. This study explored the effects of Astragalus membranaceus polysaccharide (APS) on intestinal inflammatory damage of goslings infected with parvovirus ('gosling plague').2. A total of 90 healthy goslings were randomly divided into three groups; control, infected or APS treated, respectively. Goslings in the infection and APS treatment groups were inoculated with 0.3 ml allantoic fluid containing goose parvovirus (ELD₅₀ = 1 × 10³/0.3 ml) by intramuscular injection and the control group were injected with saline (0.3 ml) twice a day for 15 days.3. Blood serum and the jejunum were collected at 5, 10 and 15 days after the start of the experiment to detect the activities of SOD and GSH-Px, levels of MDA, sIgA, IL-1β, IL-6 and TNF-α, the mRNA expression of IL-1β, IL-6, LITAF, NF-κB, COX-2 and PGE2, pathological damage in the jejunum and serum IgG, IgM, C3, C4, IFN-γ levels.4. After APS treatment, SOD and GSH-Px activities increased, MDA content decreased; sIgA, IL-1β, IL-6 and TNF-α protein content, and IL-1β, IL-6, LITAF, NF-κB, COX-2 and PGE2 mRNA expression decreased in the jejunal tissue, serum IgG, IgM, C3, C4, IFN-γ significantly increased and pathological damage of jejunum significantly improved.5. In conclusion, APS reduced intestinal inflammatory damage in goslings infected with parvovirus by improving the immune and antioxidant functions of goslings.

Building biobased, degradable, flexible polymer networks from vanillin via thiol–ene “click” photopolymerization

A new biobased allyl ether monomer with acetal groups is synthesized from renewable vanillin for building flexible transparent thiol–ene networks with good degradability under mild acidic conditions.

Role of free-breathing motion-corrected late gadolinium enhancement technique for image quality assessment and LGE quantification

OBJECTIVE

To compare the image quality and late gadolinium enhancement (LGE) quantification between free-breathing motion-corrected and conventional breath-hold LGE method in a variety of cardiovascular diseases.

MATERIALS AND METHODS

149 consecutive patients underwent contrast-enhanced cardiac magnetic resonance examination employing both free-breathing motion-corrected LGE and conventional breath-hold LGE method. Scan time, contrast-to-noise ratio, overall image quality score and LGE mass were measured and analyzed statistically.

RESULTS

Free-breathing motion-corrected LGE method had a shorter scan time and higher overall image quality score in comparison with conventional breath-hold LGE method (p < 0.001). Univariate/multivariate logistic regression analysis showed that breath-holding difficulty, high heart rate and arrhythmia could be predictive factors possibly for an inferior image quality score (p < 0.05 for all). The contrast-to-noise ratios of free-breathing motion-corrected LGE images were higher than those of conventional breath-hold LGE images (p < 0.001). In the cases with subepicardial and/or transmural myocardial enhancement, the measured LGE masses were larger on free-breathing motion-corrected LGE images in comparison with those on conventional breath-hold LGE images (p < 0.05).

CONCLUSION

Free-breathing motion-corrected LGE could be a better choice for patients who need contrast-enhanced cardiac MRI and have one or more of the risk factors for an inferior image quality score, including breath-holding difficulty, high heart rate and arrhythmia. However, an overestimation of LGE mass on free-breathing motion-corrected LGE image should be taken into consideration when LGE pattern involves subepicardial and/or transmural myocardium.

High-sensitivity nanoscale chemical imaging with hard x-ray nano-XANES

Resolving chemical species at the nanoscale is of paramount importance to many scientific and technological developments across a broad spectrum of disciplines. Hard x-rays with excellent penetration power and high chemical sensitivity are suitable for speciation of heterogeneous (thick) materials. Here, we report nanoscale chemical speciation by combining scanning nanoprobe and fluorescence-yield x-ray absorption near-edge structure (nano-XANES). First, the resolving power of nano-XANES was demonstrated by mapping Fe(0) and Fe(III) states of a reference sample composed of stainless steel and hematite nanoparticles with 50-nm scanning steps. Nano-XANES was then used to study the trace secondary phases in lithium iron phosphate (LFP) particles. We observed individual Fe-phosphide nanoparticles in pristine LFP, whereas partially (de)lithiated particles showed Fe-phosphide nanonetworks. These findings shed light on the contradictory reports on Fe-phosphide morphology in the literature. Nano-XANES bridges the capability gap of spectromicroscopy methods and provides exciting research opportunities across multiple disciplines.

Gas Sensing Performance and Mechanism of CuO(p)-WO3(n) Composites to H2S Gas

In this work, the compositional optimization in copper oxide/tungsten trioxide (CuO/WO3) composites was systematically studied for hydrogen sulfide (H2S) sensing. The response of CuO/WO3 composites changes from p-type to n-type as the CuO content decreases. Furthermore, the p-type response weakens while the n-type response strengthens as the Cu/W molar ratio decreases from 1:0 to 1:10. The optimal Cu/W molar ratio is 1:10, at which the sensor presents the ultrahigh n-type response of 1.19 × 105 to 20 ppm H2S gas at 40 °C. Once the temperature rises from 40 °C to 250 °C, the CuO/WO3 (1:1) sensor presents the p-n response transformation, and the CuO/WO3 (1:1.5) sensor changes from no response to n-type response, because the increased temperature facilitates the Cu-S bonds break and weakens the p-type CuO contribution to the total response, such that the CuS bond decomposition by a thermal effect was verified by a Raman analysis. In addition, with a decrease in CuO content, the CuO is transformed from partly to completely converting to CuS, causing the resistance of CuO to decrease from increasing and, hence, a weakening mode of p-CuO and n-WO3 to the total response turns to a synergistic mode to it.

Studies on Sensing Properties and Mechanism of CuO Nanoparticles to H2S Gas

In this work, the high crystalline copper oxide (CuO) nanoparticles were fabricated by a hydrothermal method, and their structural properties were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The sensing results show that CuO nanoparticles exhibit enhanced sensitivity and good selectivity for hydrogen sulfide (H2S) gas at a low temperature. There are two working mechanisms involved in the H2S sensing based on CuO nanoparticle sensors. They are the H2S oxidation mechanism and the copper sulphide (CuS) formation mechanism, respectively. The two sensing mechanisms collectively enhance the sensor's response in the H2S sensing process. The Cu-S bonding is stable and cannot break spontaneously at a low temperature. Therefore, the CuS formation inhibits the sensor's recovery process. Such inhibition gradually enhances as the gas concentration increases from 0.2 ppm to 5 ppm, and it becomes weaker as the operating temperature rises from 40 °C to 250 °C. The XPS results confirmed the CuS formation phenomenon, and the micro Raman spectra demonstrated that the formation of CuS bonding and its decomposition can be effectively triggered by a thermal effect. Gas-sensing mechanism analysis supplied abundant cognition for the H2S sensing phenomena based on CuO materials.

Phase dependent encapsulation and release profile of ZIF-based biocomposites

Biocomposites composed of Zeolitic Imidazolate Frameworks (ZIFs) are generating significant interest due to their facile synthesis, and capacity to protect proteins from harsh environments. Here we systematically varied the composition (i.e. relative amounts of ligand (2-methylimidazole), metal precursor (Zn(OAc)2·2H2O), and protein) and post synthetic treatments (i.e. washes with water or water/ethanol) to prepare a series of protein@ZIF biocomposites. These data were used to construct two ternary phase diagrams that showed the synthesis conditions employed gave rise to five different phases including, for the first time, biocomposites based on ZIF-CO3-1. We examined the influence of the different phases on two properties relevant to drug delivery applications: encapsulation efficiency and release profile. The encapsulation efficiencies of bovine serum albumin and insulin were phase dependent and ranged from 75% to 100%. In addition, release profiles showed that 100% protein release varied between 40 and 300 minutes depending on the phase. This study provides a detailed compositional map for the targeted preparation of ZIF-based biocomposites of specific phases and a tool for the straightforward analysis of the crystalline phases of ZIF based materials (web application named "ZIF phase analysis"). These data will facilitate the progress of ZIF bio-composites in the fields of biomedicine and biotechnology.

Sensory Impairment and All-Cause Mortality Among the Oldest-Old: Findings from the Chinese Longitudinal Healthy Longevity Survey (CLHLS)

OBJECTIVES

To investigate the association between sensory impairment and all-cause mortality among the oldest-old (aged 80 and older) in China.

DESIGN

Prospective cohort study.

SETTING

Community-based setting in 22 provinces of China.

PARTICIPANTS

A total of 8788 older adults aged 80 and over at baseline with complete hearing and vision function data were included as the study population.

MEASUREMENTS

Sensory impairment was categorized as no sensory impairment, hearing impairment (HI) only, vision impairment (VI) only and dual sensory impairment (DSI) according to hearing and vision function. Deaths were identified through interviews by close family members. Cox proportion hazards regression models were used to examine the association of sensory impairment with mortality, adjusting for socio-demographic data, life style factors and health status.

RESULTS

The mean age was 92.3 ± 7.6 years old, and 60.1% of participants were female. Among 8788 participants, 9.8% were recognized as DSI, 9.7% were HI only and 10.4% with VI only. Comparing with participants with no sensory impairment, those with VI only (HR=1.10, 95% CI=1.01-1.20) and DSI (HR=1.21, 95% CI=1.09-1.35) were significantly associated with higher risk of all-cause mortality in the fully adjusted model.

CONCLUSION

Our results demonstrated that VI only and DSI were significantly associated with higher risk of mortality among Chinese older adults aged 80 and over. The finding advocated that it is necessary to identify and manage sensory impairments for the advanced ages to reduce mortality risks.

Ethnic Groups Differences in the Prevalence of Sarcopenia Using the AWGS Criteria

OBJECTIVES

To estimate the prevalence of sarcopenia in different ethnic groups and the association with cultural life styles in west China.

DESIGN

A cross-sectional study.

SETTINGS

The communities in Yunnan, Guizhou, Sichuan, and Xinjiang provinces.

PARTICIPANTS

4500 participants aged 50 years or older in west China were enrolled in this study. Sarcopenia was defined according to the diagnostic algorithm of the Asia Working Group for Sarcopenia (AWGS).

MEASUREMENTS

We measured gait speed, handgrip strength and muscle mass by using bioelectrical impedance analysis (BIA) for all eligible participants. Life-style information were collected by reviewers. Relationships between sarcopenia and ethnic groups were analyzed using univariate and multivariate analyses.

RESULTS

We found 869 (19.31%) adults aged 50 years old or older were sarcopenia. The mean age is 62.4±8.3 years. The main ethnic groups enrolled in this study is Han, Tibetan, Qiang, Yi and Hui. The crude prevalence of sarcopenia is 22.3% in Han, 18.2% in Tibetan, 11.8% in Qiang, 34.7% in Yi and 26.7% in Hui. Compared to Han, after adjusting sex and age, Qiang has a lower prevalence of sarcopenia (odds ratio [OR]: 0.44, 95% CI 0.35-0.55), Yi has a higher prevalence of sarcopenia (OR: 1.78, 95% CI 1.29-2.43). While adding adjusting other potential cofounders, sarcopenia is still less prevalent in Qiang (OR: 0.44, 95% CI 0.34-0.57).

CONCLUSIONS

The crude prevalence of sarcopenia is 22.3% in Han, 18.2% in Tibetan, 11.8% in Qiang, 34.7% in Yi and 26.7% in Hui. Sarcopenia was less prevalent in Qiang compared with Han. Further studies to determine related factors of sarcopenia among different ethnic groups are recommended.

Association Between Number of Teeth, Denture Use and Frailty: Findings from the West China Health and Aging Trend Study

OBJECTIVE

Frailty and poor oral health are both common age-related conditions. However, the association between oral health and frailty has not been explored thoroughly among older Chinese adults. We aimed to investigate the associations between number of teeth, denture use, and frailty among older adults in western China.

DESIGN

Cross-sectional study.

SETTING

Community-based.

PARTICIPANTS

Participants were 4037 community-dwelling individuals aged 60 and older from the West China Health and Aging Trend (WCHAT) study.

MEASUREMENTS

Frailty was assessed using the physical frailty phenotype (PFP) and categorized as non-frail, prefrail and frail. In addition, number of teeth and denture use were examined by calibrated dentists. Multinomial logistic regression models were performed to examine the association between number of teeth, denture use, and frailty.

RESULTS

The overall prevalence of frailty was 6.7% among 4037 participants aged 60 and older in western China. Participants with no more than 20 teeth were associated with higher odds of being prefrail or frail whether wearing dentures or not. Denture using could not help lower the odds of being prefrail or frail for older adults with fewer teeth.

CONCLUSIONS

This study suggested that frailty was associated with having fewer teeth (≤20 teeth) among older Chinese adults. Future research involving targeted interventions addressing number of teeth may help provide information to establish effective strategies for frailty prevention in older adults.

Sarcopenia, Obesity and Sarcopenia Obesity in Comparison: Prevalence, Metabolic Profile, and Key Differences: Results from WCHAT Study

OBJECTIVE

To identify the prevalence, lifestyle factors, chronic disease status, and assessing the metabolic profile, comparing key differences in a cohort of subjects with non-sarcopenia/non-obesity (H), sarcopenia/non-obesity (S), non-sarcopenia/obesity (O) and sarcopenia obesity (SO) in a multi-ethnic population in west China.

DESIGN

A cross-sectional study.

SETTING

The communities in Yunnan, Guizhou, Sichuan, and Xinjiang provinces.

PARTICIPANTS

We included 4,500 participants aged 50 years or older who did bioelectrical impedance in our analysis from West China Health and Aging Trend (WCHAT) study.

MEASUREMENTS

We measured gait speed, handgrip strength and muscle mass by using bioelectrical impedance analysis (BIA) for all participants. We defined sarcopenia using the diagnostic algorithm recommended by the Asian Working Group for Sarcopenia (AWGS). Obesity was defined as the highest sex-specific quintile of the percentage body fat. Different variables like anthropometry measures, life styles, chronic disease and blood test were collected. Analysis of variance and a multinomial logistic regression analysis adjusting for covariates were used to assess the differences of metabolic profiles among different groups.

RESULTS

Of 4500 participants aged 50 years old or older, the proportions of H, O, S, SO were 63.0%, 17.7%, 16.7% and 2.6%, respectively. And the prevalence of S subjects in men was 18.3% and 15.7% in women, while the prevalence of SO was 3.7% in men and 2.0% in women. Data showed that the prevalence of S and SO has an aging increase pattern which was opposite with O. Both S and SO tends to be older, lower educational level, without spouse, smoking, comorbidity of chronic disease, poor nutrition status, depression and cognitive decline compared to H and S seems to be worse than SO. Compared to H, S cohort showed a decrease in Vitamin D, triglyceride, albumin, fasting glucose, insulin, creatinine, ALT, nutrition scores and increase in HDL. SO cohort were observed for an increase in cholesterol, LDL, total protein and decrease in vitamin D. While O cohort showed an increase in triglyceride, cholesterol, LDL, total protein, glucose, insulin, WBC, uric acid, ALT and nutrition scores, but a decrease in HDL and vitamin D level.

CONCLUSIONS

Among individuals aged 50 years old or older in West China. S, O and SO participants demonstrate distinct differences in the life-styles, chronic disease profile, and metabolic profiles. The prevalence of S and SO has an aging increase pattern contrary to O. Both S and SO tend to be older, lower educational level, without spouse, smoking, comorbidity of chronic disease, poor nutrition status, depression and cognitive decline compared to H and S looks like to be worse than SO. Besides, the S subjects seem to have more metabolic index changes than SO compared to H. While O subjects have some contrary metabolic index to S subjects.

Prevalence and Its Associated Factors of Physical Frailty and Cognitive Impairment: Findings from the West China Health and Aging Trend Study (WCHAT)

OBJECTIVES

Previous literature has reported that physical frailty (PF) closely associated with cognitive impairment (CI). In this study, we aim to describe and evaluate the prevalence and associated factors with different patterns of PF and cognitive impairment.

DESIGN

A cross-sectional study.

SETTING AND PARTICIPANTS

Community-dwelling older adults aged ≥60 from the West China Health and Aging Trend (WCHAT) study were included in this study.

MEASUREMENTS

Participants were assessed the PF and cognitive impairment. PF was assessed using the physical phenotype as defined by Fried's criteria. Cognitive impairment was identified using the Short Portable Mental Status Questionnaire (SPMSQ). According different patterns of PF and cognitive impairment, participants were divided into 4 groups: not-PF and cognitive intact ( "neither" group), not-PF and cognitive impairment ("CI only" group), PF and cognitive intact ("PF only" group), and PF and cognitive impairment ("both" group). Multinomial logistic regression was used to explore the association between medical conditions and different patterns of PF and cognitive impairment after adjusting the demographic characteristics.

RESULTS

Among 4,103 participants (age 67.8 + 5.9 years, female 58.3%), 78.8%, 3.9%, 14.5% and 2.9% were "neither", "PF only", "CI only", and "both", respectively. The prevalence of "PF only", "CI only" and "both" were associated with age, lower education level and single status. In addition, there was substantial ethnicity heterogeneity in the prevalence of different patterns of PF and cognitive impairment. Comparing with "neither", PF and/or cognitive impairment had higher association with depression, ADLs impairment, and malnutrition. Of note, obesity was only significantly associated with "PF only", but not associated with "CI only" or "both".

CONCLUSIONS

We found the substantial demographic and medical conditions disparities in different patterns of PF and cognitive impairment. Further research should focus on the efficient and practical screen to predict the risk of "PF only", "CI only" and "both".

Dynamic Imine Bond-Based Shape Memory Polymers with Permanent Shape Reconfigurability for 4D Printing

Shape memory polymer (SMP)-based 4D printing combines the advantages of SMP and 3D printing to form active materials with delicate structure. Nowadays, studies of SMP-based 4D printing materials mainly focus on cross-linked (meth)acrylate of which the permanent shape cannot be changed for their covalent linkage, limiting the usage of 4D printing materials. In this paper, a novel (meth)acrylate monomer with an aldehyde group (2-(methacryloyloxy)ethyl 4-formylbenzoate, MEFB) and hyperbranched cross-linker (HPASi) are synthesized to build (meth)acrylate systems (IEMSis) with dynamic imine bonds for 4D printing. The flexible chain structure of HPASi significantly enhances the toughness of IEMSis, which is 33-97-fold higher than that of the one without HPASi (IEM). The addition of HPASi also endows IEMSis good shape memory properties, and the shape fixity and shape recovery ratios of them are 97.5-97.6 and 91.4-93.7%, respectively. At the same time, IEMSis can undergo a stress relaxation process by dynamic exchanges of imine bonds under relatively mild conditions without a catalyst to acquire an ability of permanent shape reconfiguration. The shape retention ratio of IEMSi3 is 84.3%. In addition, the 4D-printed structures displayed here indicate that these 4D printing systems have a myriad of potential applications including aerospace structures, soft robotic grippers, smart electron switches, and intelligent packaging, while the reconfigurability shown by IEMSi3 will expand the scope of application fields of 4D printing materials.

SMPDL3b modulates insulin receptor signaling in diabetic kidney disease

Sphingomyelin phosphodiesterase acid-like 3b (SMPDL3b) is a lipid raft enzyme that regulates plasma membrane (PM) fluidity. Here we report that SMPDL3b excess, as observed in podocytes in diabetic kidney disease (DKD), impairs insulin receptor isoform B-dependent pro-survival insulin signaling by interfering with insulin receptor isoforms binding to caveolin-1 in the PM. SMPDL3b excess affects the production of active sphingolipids resulting in decreased ceramide-1-phosphate (C1P) content as observed in human podocytes in vitro and in kidney cortexes of diabetic db/db mice in vivo. Podocyte-specific Smpdl3b deficiency in db/db mice is sufficient to restore kidney cortex C1P content and to protect from DKD. Exogenous administration of C1P restores IR signaling in vitro and prevents established DKD progression in vivo. Taken together, we identify SMPDL3b as a modulator of insulin signaling and demonstrate that supplementation with exogenous C1P may represent a lipid therapeutic strategy to treat diabetic complications such as DKD.

Improving gas sensing performance by oxygen vacancies in sub-stoichiometric WO3-x

Sub-stoichiometric WO3-x has provided an alternative platform to investigate oxygen vacancies in gas sensors based on metal-oxides. We present an experimental study on the influence of sub-stoichiometric WO3-x phase upon gas sensing performance. High-quality WO3-x nanostructures with several x values (WO3, W19O55, W5O14, W18O49) were synthesized and used to fabricate H2S gas sensors. Temperature programmed desorption of oxygen (O2-TPD) shows that oxygen absorption behaviors of the as-prepared WO3-x nanostructures are affected by oxygen vacancies, which played a critical role in the detection of H2S at varying temperature range. We find that oxygen vacancies in sub-stoichiometric WO3-x facilitate the ionosorption process and in turn enhance the performance of the gas sensor.

[Treatment experience of cardiac rupture in patients with acute myocardial infarction]

Objective: To analyze the treatment results of cardiac rupture in patients with acute myocardial infarction (AMI) . Method: Clinical data of 6 with cardiac rupture after AMI, who were hospitalized in our hospital from June 2015 to June 2017, were retrospectively analyzed,and the clinical manifestations, methods of treatment and outcomes were investigated. Results: Cardiac function classification was Killip class Ⅱin all patients. There were 3 massive anterior wall myocardial infarction, 2 anterior wall myocardial infarction,and 1 inferior myocardial infarction. There were 4 patients with ventricular septal defect, 1 patient with rupture of papillary muscle,and 1 patient with left ventricular free wall rupture.All patients received continuous infusion of vasoactive medicines and treated with intra-aortic balloon pump(IABP), 2 patients (1 patient accepted operative treatment,and 1 patient received conservative treatment) were treated with extracorporeal membrane oxygenation (ECMO), mechanical ventilation,and continuous renal replacement therapy(CRRT).Three patients received surgical repair,1 case was supported by IABP, 1 case supported by ECMO,CRRT,and IABP,and 1 case did not use IABP or ECMO post operation. All 3 surgically treated patients recovered successfully and were discharged from hospital.Meanwhile, in the other 3 patients treated conservatively, 2 patients died in the hospital and 1 patient was discharged according to own will. Conclusion: On the basis of vasoactive medicines and IABP, surgery repair is a feasible option for cardiac rupture patients secondary to AMI,and ECMO may improve the perioperative state in these patients.

Enhanced gas selectivity induced by surface active oxygen in SnO/SnO2 heterojunction structures at different temperatures

The development of heterojunction structures has been considered as an important step for sensing materials.

[Clinical features and diagnosis of childhood leukoencephalopathy with cerebral calcifications and cysts in four cases]

Objective: To investigate the clinical features and diagnostic bases of childhood leukoencephalopathy with cerebral calcifications and cysts (LCC). Methods: The clinical data involving manifestations and laboratory examinations of 4 children with LCC admitted to Beijing Children's Hospital Affiliated to Capital Medical University from 2012 to 2017 were retrospectively summarized. Each patient had a follow-up visit ranging from 4 months to 5 years and 9 months after initial examination. Results: Patients consisted of 2 males and 2 females, whose age of onset was respectively 2 years and 9 months, 6 years and 2 months, 7 years and 10 months, and 5 years and 1 month. The main clinical symptoms of these cases included headache, dizziness, partial seizure and claudication, and two of these cases had insidious onset. Cerebral calcifications and cysts with leukoencephalopathy were detected by neuroimaging in all patients. In addition, multifocal microhemorrhages and calcifications were observed by magnetic susceptibility-weighted imaging (SWI) series in 3 patients. Brain biopsy performed on 1 case disclosed a neuronal reduction in the cerebral cortex, loosening of focal white matter, multifocal lymphocyte infiltration, fresh hemorrhages, and gliosis, as well as angiomatous changes of blood vessels with hyalinized thicken-wall, stenotic or occlusive lumina and calcification deposits. The compound heterozygous mutations of n.*10G>A and n.82A>G in SNORD118 were identified in 1 case by target-capture next-generation sequencing. Sanger sequencing verified that the variant n.*10G>A was a novel mutation and it was of paternal-origin, while the variant n.82A>G was of maternal-origin, which had already been reported to be pathogenic to LCC. Follow-up study had shown continued partial seizure in 1 case and remissive claudication in another, while the remaining 2 cases had a relatively favorable outcome without obvious neurological symptoms at present time. Conclusions: The clinical manifestations of LCC are nonspecific, and the onset of the disease tends to be insidious. The triad neuroimaging findings of cerebral calcifications, cysts and leukoencephalopathy are essential to the diagnosis of the disease, and the signals of microhemorrhages revealed by SWI series provide another eloquent reference for the diagnosis. As biopsy is invasive and usually unavailable in the early stage, gene assessment, instead of pathological data, should be the gold standard in the diagnosis of LCC.

Absolute CBV for the differentiation of recurrence and radionecrosis of brain metastases after gamma knife radiotherapy: a comparison with relative CBV

AIM

To investigate the efficiency of absolute cerebral blood volume (CBV) in the differentiation of tumour recurrence (TR) and radionecrosis (RN) in brain metastases (BM) and to evaluate the performance of absolute CBV compared to relative CBV (rCBV).

MATERIALS AND METHODS

Between March 2015 and June 2017, 46 patients with BM underwent quantitative dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) because new enhancement had been demonstrated in irradiated lesions after gamma knife radiotherapy. The patients were assigned to either the TR group or RN group on the basis of MR perfusion follow-up or histopathological outcome. Absolute CBV of lesions (CBVlesion) and contralateral normal appearing white matter (CBVNAWM) in both groups were obtained. Mean rCBV were calculated as CBVlesion/CBVNAWM, which was equal to rCBV using traditional DSC-PWI.

RESULTS

CBVlesion of TR alone was significantly higher than the other parameters in both groups (p<0.001, separately). CBVlesion had smaller interobserver difference than CBVNAWM and rCBV (p<0.001, separately). Although CBVlesion significantly correlated with rCBV (r=0.914, p<0.001) and both had a similar specificity (96%) in differential diagnosis, CBVlesion had a higher sensitivity (96.9% versus 90.9%) to predict the treatment outcome. The best cut-off value of CBVlesion was 21.8 ml/100 g.

CONCLUSION

Quantitative DSC-PWI is a powerful method for the assessment of radiosurgically treated brain metastases. Absolute CBV has higher diagnostic efficiency than rCBV, which enables an absolute quantification of the regional CBV and prediction of tumour response. These advantages promote the intra- and inter-patient quantitative image comparison across different institutions.

Association of sarcopenia and fractures in community-dwelling older adults: a systematic review and meta-analysis of cohort studies

To our knowledge, no comprehensive meta-analysis has examined the association between sarcopenia and the risk of fractures. This systematic review and meta-analysis of prospective cohort studies aims to summarize whether sarcopenia is a risk factor for fractures among community-dwelling older adults. We searched four electronic literature databases (Ovid MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, PubMed) for relevant publications from inception to December 2017, using relevant keywords. We conducted a pooled analysis of the association between sarcopenia and the risk of fractures by employing a random-effects model. Subgroup analyses were conducted based on definitions of sarcopenia and gender. In total, nine studies were included in our systematic review and meta-analysis. The prevalence of sarcopenia ranged from 4.3 to 33.1%. The pooled RR of fractures for the sarcopenic versus the nonsarcopenic was 1.34 (95% CI = 1.13-1.58, P = 0.001, I² = 5.5%, P-heterogeneity = 0.391). Subgroup analyses showed that associations between sarcopenia and fractures were significant when using the AWGS definition (combined effect size = 1.78, 95% CI = 1.25-2.54, P = 0.001), and studies in males (combined effect size = 1.39, 95% CI = 1.13-1.71, P = 0.002). In conclusion, we found that compared to nonsarcopenic, the association between sarcopenia and fractures among community-dwelling older people was significant when using the AWGS definition, and only for males. Future studies are needed to establish a possible association between sarcopenia definitions and risk of fractures of different sites.