[Clinical features and prognostic analysis of checkpoint inhibitor pneumonitis in patients with non-small cell lung cancer]

Objective: To describe the clinical characteristics of patients with non-small cell lung cancer (NSCLC) who developed checkpoint inhibitor pneumonitis (CIP) and to explore potential prognostic factors. Methods: NSCLC patients who were complicated with CIP after immune checkpoint inhibitors (ICIs) therapy in our institute were enrolled in this study from 1 July 2018 to 30 November 2022. Clinical data of NSCLC-CIP patients were collected, including clinical and radiological features and their outcomes. Results: Among the 70 enrolled NSCLC-CIP patients, there were 57 males (81%) and 13 females (19%). The mean age at the diagnosis of CIP was (65.2±6.3) years. There were 46 smokers (66%), 26 patients (37%) with emphysema, 19 patients (27%) with previous interstitial lung disease, and 26 patients (37%) with a history of thoracic radiation. The mean interval from the first application of checkpoint inhibitor to the onset of CIP was (122.7±106.9) days (range: 2-458 days). The main chest CT manifestations were coincided with non-specific interstitial pneumonia (NSIP) pattern and organizing pneumonia (OP) pattern. Most patients had grade 2 (21 cases) or grade 3 (34 cases) CIP. Seventeen patients had been concurrent with other immune-related adverse events such as rash, hepatitis, colitis, and thyroiditis. Half of the enrolled patients (36 patients/51%) had fever, and most patients had elevated C-reactive protein (52 patients/72%) and all patients had elevated erythrocyte sedimentation rate (70 patients/100%). Serum lactate dehydrogenase was elevated in 34 CIP patients. Prednisone≥1 mg·kg-1·d-1 (or equivalent) was the most commonly used initial treatment in CIP patients (50 patients/71.4%). Complications with pulmonary infections (OR=4.44, P=0.03), use of anti-fungal drugs (OR=5.10, P=0.03) or therapeutic dose of sulfamethoxazole (OR=4.86, P=0.04), longer duration of prednisone≥1 mg·kg-1·d-1 (or equivalent) (Z=-2.33, P=0.02) were probable potential risk factors for poor prognosis. Conclusions: Older males with smoking history might be predisposed to develop NSCLC-CIPs after ICIs therapy. NSIP pattern and OP pattern were common chest CT manifestations. Complications with pulmonary infections (especially fungal infection or Pneumocystis jirovecii pneumonia), longer duration, longer duration of high-dose corticosteroids were likely potential risk factors for poor prognosis.

[Clinical analysis of COVID-19 in patients with preexisting interstitial lung abnormalities]

Objective: To describe the clinical characteristics of SARS-CoV-2 infected patients with interstitial lung abnormalities (ILA) during the COVID-19 pandemic. Methods: We respectively enrolled ILA patients who had been regularly followed up in Peking Union Medical College Hospital for more than six months since January 2021. Clinical data of these ILA patients were collected after the outbreak of COVID-19 pandemic (from December 2022 to January 2023), thirty-eight patients with preexisting ILA were enrolled. Among them, there were 34 ILA patients (20 males and 14 females) who were infected with SARS-CoV-2 during this period, with an average age of (64.0±8.8) years old (range: 41-80). There were 12 (35.3%) ILA patients who were suffered from COVID-19(pneumonia group) and others were the non-pneumonia group. The clinical characteristics, including vaccination status, features of COVID-19 and outcomes of the two groups were compared. Results: Regarding the subcategories of ILA, there were 7 cases of subpleural fibrotic ILA, 10 cases of subpleural non-fibrotic ILA, and 17 cases of non-subpleural ILA. Before SARS-CoV-2 infection, the average pulse oxygen saturation at rest was (97.38±0.87)% (range: 96%-99%); average forced vital capacity (FVC) was (97.6±18.1)% predicted (range: 65%-132%); and average diffusion capacity for carbon monoxide (DLCO) was (76.2±16.3)% predicted (range: 53%-108%). Nineteen patients had been vaccinated with 3 doses of SARS-CoV-2 vaccines, and 5 of them developed COVID-19. One patient had received one dose of vaccine and did not develop COVID-19. The other 14 patients had not been vaccinated, and seven of them developed COVID-19. Of the 12 patients with COVID-19, six were diagnosed with severe COVID-19, and the other 6 ILA patients were diagnosed with moderate COVID-19. Among them, 1 patient was complicated by deep vein thrombosis of left lower limb. All 6 patients with severe COVID-19 who were cured after systemic corticosteroids. As for the other six moderate COVID-19 patients, all were cured and/or improved greatly: two were treated with short-term oral corticosteroids, one was prescribed a dose of compound betamethasone, and the other two were not treated with systemic corticosteroids. Conclusion: Patients with ILA were predisposed to develop COVID-19 after infection with SARS-CoV-2, and more than half of them had severe COVID-19.

Exosomes Derived from Astragaloside IV-pretreated Endothelial Progenitor Cells (AS-IV-Exos) Alleviated Endothelial Oxidative Stress and Dysfunction Via the miR-210/ Nox2/ROS Pathway

BACKGROUND

Chronic hyperglycemia in diabetes induces oxidative stress, leading to damage to the vascular system. In this study, we aimed to evaluate the effects and mechanisms of AS-IV-Exos in alleviating endothelial oxidative stress and dysfunction caused by high glucose (HG).

METHODS

Histopathological changes were observed using HE staining, and CD31 expression was assessed through immunohistochemistry (IHC). Cell proliferation was evaluated through CCK8 and EDU assays. The levels of ROS, SOD, and GSH-Px in the skin tissues of each group were measured using ELISA. Cell adhesion, migration, and tube formation abilities were assessed using adhesion, Transwell, and tube formation experiments. ROS levels in HUVEC cells were measured using flow cytometry. The levels of miR-210 and Nox2 were determined through quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The expression of Nox2, SOD, GSH-Px, CD63, and CD81 was confirmed using WB.

RESULTS

The level of miR-210 was reduced in diabetes-induced skin damage, while the levels of Nox2 and ROS increased. Treatment with AS-IV increased the level of miR-210 in EPC-Exos. Compared to Exos, AS-IV-Exos significantly reduced the proliferation rate, adhesion number, migration speed, and tube-forming ability of HGdamaged HUVEC cells. AS-IV-Exos also significantly decreased the levels of SOD and GSH-Px in HG-treated HUVEC cells and reduced the levels of Nox2 and GSH-Px. However, ROS levels and Nox2 could reverse this effect.

CONCLUSION

AS-IV-Exos effectively alleviated endothelial oxidative stress and dysfunction induced by HG through the miR-210/Nox2/ROS pathway.

Effect and Mechanism of Sodium Butyrate on Neuronal Recovery and Prognosis in Diabetic Stroke

Ischemic stroke is a cerebrovascular lesion caused by local ischemia and hypoxia. Diabetes mellitus (DM) is a chronic inflammatory disease that disturbs immune homeostasis and predisposes patients to ischemic stroke. The mechanism by which DM exacerbates stroke remains unclear, although it may involve disturbances in immune homeostasis. Regulatory T cells (Tregs) play a regulatory role in many diseases, but the mechanism of Tregs in diabetes complicated by stroke remains unclear. Sodium butyrate is a short-chain fatty acid that increases Treg levels. This study examined the role of sodium butyrate in the prognosis of neurological function in diabetic stroke and the mechanism by which Tregs are amplified in the bilateral cerebral hemispheres. We evaluated the brain infarct volume, observed 48-h neuronal injury and 28-day behavioral changes, and calculated the 28-day survival rate in mice. We also measured Treg levels in peripheral blood and brain tissue, recorded changes in the blood‒brain barrier and water channel proteins and neurotrophic changes in mice, measured cytokine levels and peripheral B-cell distribution in bilateral hemispheres and peripheral blood, and examined the polarization of microglia and the distribution of peripheral T-cell subpopulations in bilateral hemispheres. Diabetes significantly exacerbated the poor prognosis and neurological deficits in mice with stroke, and sodium butyrate significantly improved infarct volume, prognosis, and neurological function and showed different mechanisms in brain tissue and peripheral blood. The potential regulatory mechanism in brain tissue involved modulating Tregs/TGF-β/microglia to suppress neuroinflammation, while that in peripheral blood involved improving the systemic inflammatory response through Tregs/TGF-β/T cells.

[Whole-course management strategies for gastroesophageal reflux disease: an evidence mapping study based on clinical practice guidelines]

Gastroesophageal reflux disease (GERD) is one of the most common digestive diseases with high incidence, complicated clinical symptoms, difficulties in standard treatment, and heavy medical burden. At present, some GERD-relevant clinical practice guidelines (CPGs) have been issued by different countries and academic organizations, but some recommendations were inconsistent, which has caused some problems for the current clinical whole-course management of GERD. To summarize the relevant evidence among the CPGs on GERD and formulate the whole- course management strategies, we included GERD-relevant CPGs published or updated after 2010 by searching websites of guidelines, relevant professional societies, and electronic databases. We extracted the recommendations and summarized the evidence from the aspects of symptoms, epidemiology, diagnosis and treatment, which was presented in the form of evidence mapping. We included 24 CPGs, including three in Chinese and 21 in English. The clinical practice management strategies of GERD were formulated based on the evidence from the aspects of clinical symptoms, diagnostic methods, medical treatment, anti-reflux surgery and endoscopic treatment, psychological treatment, and traditional Chinese medicine treatment.

[Retrospective analysis and a cross-sectional questionnaire survey of lung cancer concomitant with interstitial lung disease]

Objective: To describe the clinical characteristics and prognosis of lung cancer concomitant with interstitial lung disease (LC-ILD), and to understand the current status of knowledge of LC-ILD by physicians in the departments related to the treatment of the disease. Methods: We conducted a retrospective analysis of in-hospitalized pathology identified lung cancer (LC) patients who were admitted to our hospital between January 2014 and December 2018. After reviewing their chest CT imagings and pathological reports, 70 patients who were concomitant with interstitial lung disease (ILD) were enrolled in our study. On the other hand, a cross-sectional survey using an online questionnaire was conducted in LC-ILD management doctors who came from 29 provincial hospitals. The perceptions of demographic features, LC characteristics and management, ILD characteristics and management, and the prognosis of LC-ILD were investigated. Results: Among the 70 enrolled LC-ILD cases, there were 52 males, and the mean age was (64.3±7.63) years (ranged from 49 years to 84 years). There were 51 patients who were older than 59 years. The most common pathological pattern of LC was adenocarcinoma. Most of them were diagnosed with LC and ILD simultaneously, and they were usually treated with chemotherapy while unresectable. There were 11 patients (15.7%) with positive EGFR or ALK mutation. Forty-five patients (64.3%) died during the follow-up, and 33 were died from LC progression. There were no significant differences between the surgical group and non-surgical group on age, pathological patterns, EGFR or ALK mutation. However, LC-ILD patients in the surgical group were diagnosed with earlier TNM classification and with better prognosis. A total of 1 014 doctors answered the questionnaire completely. In the feedback, patients aged 60 years and older (785 doctors/77.4%), and male patients (720 doctors/71%) were the predominant LC-ILD patients. Adenocarcinoma (390 doctors/38.5%), adenocarcinoma or squamous-cell cancer (SCC) (182 doctors/17.9%), and SCC (151 doctors/14.9%) were considered as the common pathological patterns of LC-ILD patients. In most doctors' feedback, the EGFR or ALK mutation was not common for LC-ILD: low (646 doctors/63.7%) or hardly (306 doctors/30.5%) positive mutation. The diagnosis of ILD was earlier than LC (506 doctors/49.9%) or there was no identified precedence of LC and ILD diagnosis (208 doctors/20.5%). Most of the doctors (693 doctors/68.3%) agreed that the vital factor for surgery or not was the severity of ILD for LC-ILD patients. There were great divergences on the treatment protocol both for the advanced LC and ILD. The patients with LC-ILD were died mostly from LC progression and ILD exacerbation (542 doctors/53.5%), followed by ILD exacerbation (237 doctors/23.4%) or LC progression (226 doctors/22.3%). Conclusions: The elderly male patients were predisposed to LC-ILD, and adenocarcinoma was the common pathological pattern. The LC-ILD patients with non-advanced LC who were performed with surgery had better prognosis. However, it is recommended to consider whether to perform surgery in combination with the severity of the ILD.

[Host factors and characteristics of hospitalized patients with pneumocystis jirovecii pneumonia]

Objectives: To describe the underlying diseases, microbiologic examination and severity of hospitalized patients with Pneumocystis jirovecii pneumonia (PJP) in a tertiary Chinese hospital. Methods: We conducted a retrospective analysis of 485 identified PJP patients who were admitted to our hospital between January 2013 and December 2021. Results: Among the 485 enrolled PJP cases, there were 237 males and 248 females, aging (53.3±16.2) years (range from 14 y to 88 y). They were divided into 8 subgroups with variable underlying diseases. There were 209 cases with connective tissue diseases(CTD), 27 cases with non-hematologic malignancies, 38 cases with hematologic malignancies, 81 cases with kidney diseases, 33 cases with idiopathic interstitial pneumonia(IIP), 30 cases infected with human immunodeficiency virus (HIV), and 42 cases with miscellaneous underlying diseases. In the CTD group, there was more females than males, while male patients were predominant in both the malignant and the HIV groups. The Pneumocystis was identified in 44.95%(218/485) sputum samples and 92.01%(265/288) bronchoscopic samples. Pneumocystis asci were observed at direct microscopic examination with Grocott's methenamine silver stain in 4.95%(24/485)sputum samples and 9.72%(28/288)bronchoscopic samples. Pneumocystis DNA fragments were identified by PCR analysis in 43.09%(209/485)sputum samples and 90.63%(261/288)bronchoscopic samples. Among the 8 groups, cytomegaviremia and respiratory failure were most common in the HIV-infected PJP group, but the rates of mechanic ventilation, intensive care unit (ICU) admission and death were the lowest. There were less PJP patients in the IIP group (IIP-PJP) who received mechanic ventilation and admitted to ICU than the other groups except HIV-infected PJP group. However, the mortality rate was highest for the IIP-PJP group. Conclusions: CTD was the most common predisposed underlying disease for our enrolled PJP cases. Cytomegaviremia and respiratory failure were common in HIV-infected PJP patients, but the prognosis of HIV-PJP was slightly better than the others. The disease was more severe, rapidly progressive and fatal in the IIP-PJP group.

[Clinical analysis of autoimmune diseases associated with interstitial lung diseases initially presented with idiopathic pulmonary fibrosis]

Objectives: To describe the clinical characteristics of patients with autoimmune diseases associated interstitial lung diseases (AID-ILD) initially presented with idiopathic pulmonary fibrosis (IPF) in a tertiary Chinese hospital. Methods: We conducted a retrospective analysis of 14 patients diagnosed with AID-ILD during the IPF follow-up between January 2016 and December 2021. Among the 14 enrolled AID-ILD cases, there were 13 males and 1 female, (69.71±9.07) years old (range from 55 y to 87 y). Results: Detailed clinical consultation and further laboratory analysis were performed during the follow-up when the IPF patients showed exaggerated dyspnea (7 cases), fever of unknown causes (6 cases), microscopic hematuria (5 cases), arthralgia and swelling (4 cases), arthralgia (2 cases), morning stiffness (2 cases) and renal failure (2 cases). Finally, 6 patients showed positive MPO-ANCA, one patient showed positive PR3-ANCA and 7 patients showed positive anti-CCP. During the IPF periods, 7 patients had received antifibrotic agents and 5 patients had been prescribed with N-acetylcysteine, and 1 patient had received antifibrotic agents after N-acetylcysteine. Among them, no medication was prescribed for one IPF patient. After they were diagnosed with AID-ILD, glucocorticoids and/or immunosuppressants were added for 13 of them. Thirteen of cases improved or stable after these treatments, but one didn't show significant changes. Conclusions: AID-UIP, especially ANCA-UIP, AAV-UIP or RA-UIP should be considered when the IPF patients showed fever of unknown origin, microscopic hematuria and/or arthritis related symptoms. They might benefit from the add-on glucocorticoids and/or immunosuppressants.

[Preventive strategy of economy class syndrome]

Economy class syndrome (ECS) refers to a series of symptoms, such as lower limb swelling, chest pain, dyspnea, and sudden death, that occur during or after a long-distance flight. Its essence is venous thromboembolism. ECS, as a preventable syndrome, is one of the causes of sudden death in long-distance travelers. Medical assistance to the African region is a very important diplomatic matter of China. It often takes medical workers more than 10 hours of long-distance flight to reach the recipient country. Therefore, it is essential to improve the understanding of ECS and corresponding prevention strategies among the long-distance traveling people including medical workers assisting Africa, which could guarantee their health and ensure the smooth implementation of the work of assisting Africa.

[Sorafenib regulates vascular endothelial growth factor by runt-related transcription factor-3 to inhibit angiogenesis in hepatocellular carcinoma]

Objective: To investigate the molecular mechanism of sorafenib against hepatocellular carcinoma. Methods: Sorafenib efficacy was screened and verified by the hepatocellular carcinoma patient-derived tumor xenograft (PDX) model. Veterinary B-mode ultrasonography and in vivo confocal laser scanning microscopy were used to observe PDX angiogenesis. Immunohistochemistry was used to observe the expression of proliferation and angiogenesis-related proteins in PDX tissue. Real-time quantitative PCR technology was used to observe the RUNX3 gene in PDX tissues. SPSS 17.0 statistical software was used for statistical analysis. Results: Four cases of PDX were used to screen the efficacy of sorafenib. PDX1 had a significant response to sorafenib, with an inhibition rate of 68.07%. Compared with the control group, sorafenib had significantly inhibited PDX1 relative tumor volume (5.76±2.14 vs. 11.71±2.87, P<0.05). Cell division index (39.50±7.72 vs. 67.10±9.14, P<0.05) and Ki67 expression (288.6±43.40 vs. 531.70±55.60, P<0.05) were significantly decreased. Veterinary B-mode ultrasonography showed evident blood flow signals in PDX1 tumors. In vivo confocal laser scanning microscopy results showed that sorafenib had significantly reduced the total vessel length (1573.00±236.21 vs. 2675.03±162.00, P<0.05) and area (11 145.33±1931.97 vs. 20 105.37±885.93, P<0.05)) of PDX1 tumors. Immunohistochemical results showed that sorafenib had significantly down-regulated the protein expressions of CD34 (27.55±3.76 vs. 45.47±5.57, P<0.05), VEGF (16.33±2.86 vs. 22.77±3.20, P<0.05) and MVD (38.75±6.01 vs. 55.50±8.61, P<0.05). Real-time PCR results showed that sorafenib had significantly up-regulated RUNX3 gene expression (2.14±0.71 vs. 1.00±0.36, P<0.05). However, there was a negative correlation between the expression of RUNX3 gene and the ratio of VEGF-positive cells in sorafenib group (R²=0.509 7). Conclusion: Sorafenib may inhibit the PDX angiogenesis and the growth of hepatocellular carcinoma by regulating the RUNX3-VEGF pathway.

Stellate ganglion block reduces inflammation and improves neurological function in diabetic rats during ischemic stroke

Diabetes mellitus is an independent risk factor for ischemic stroke. Both diabetes mellitus and stroke are linked to systemic inflammation that aggravates patient outcomes. Stellate ganglion block can effectively regulate the inflammatory response. Therefore, it is hypothesized that stellate ganglion block could be a potential therapy for ischemic stroke in diabetic subjects. In this study, we induced diabetes mellitus in rats by feeding them a high-fat diet for 4 successive weeks. The left middle cerebral artery was occluded to establish models of ischemic stroke in diabetic rats. Subsequently, we performed left stellate ganglion block with 1% lidocaine using the percutaneous posterior approach 15 minutes before reperfusion and again 20 and 44 hours after reperfusion. Our results showed that stellate ganglion block did not decrease the blood glucose level in diabetic rats with diabetes mellitus but did reduce the cerebral infarct volume and the cerebral water content. It also improved the recovery of neurological function, increased 28-day survival rate, inhibited Toll like receptor 4/nuclear factor kappa B signaling pathway and reduced inflammatory response in the plasma of rats. However, injection of Toll like receptor 4 agonist lipopolysaccharide 5 minutes before stellate ganglion block inhibited the effect of stellate ganglion block, whereas injection of Toll like receptor 4 inhibitor TAK242 had no such effect. We also found that stellate ganglion block performed at night had no positive effect on diabetic ischemic stroke. These findings suggest that stellate ganglion block is a potential therapy for diabetic ischemic stroke and that it may be mediated through the Toll like receptor 4/nuclear factor kappa B signaling pathway. We also found that the therapeutic effect of stellate ganglion block is affected by circadian rhythm.

Dual Recognition DNA Triangular Prism Nanoprobe: Toward the Relationship between K+ and pH in Lysosomes

Lysosomal acidification is essential for its degradative function, and the flux of H⁺ correlated with that of K⁺ in lysosomes. However, there is little research on their correlation due to the lack of probes that can simultaneously image these two ions. To deeply understand the role of K⁺ in lysosomal acidification, here, we designed and fabricated a nanodevice using a K⁺-aptamer and two pH-triggered nanoswitches incorporated into a DNA triangular prism (DTP) as a dual signal response platform to simultaneously visualize K⁺ and pH in lysosomes by a fluorescence method. This strategy could conveniently integrate two signal recognition modules into one probe, so as to achieve the goal of sensitive detection of two kinds of signals in the same time and space, which is suitable for the detection of various signals with the correlation of concentration. By co-imaging both K⁺ and H⁺ in lysosomes, we found that the efflux of K⁺ was accompanied by a decrease of pH, which is of great value in understanding lysosomal acidification. Moreover, this strategy also has broad prospects as a versatile optical sensing platform for multiplexed analysis of other biomolecules in living cells.

Characterization of HPV subtypes not covered by the nine-valent vaccine in patients with CIN 2-3 and cervical squamous cell carcinoma

BACKGROUND

As the second most common female malignant tumor, cervical cancer is also one of the most preventable and avoidable cancers. The World Health Organization has launched a global plan to accelerate the elimination of cervical cancer. Therefore, in the era of postvaccine, the role of HPV subtypes in cervical precancerous lesions and cervical cancer that are not covered by vaccine should be further discussed. The purpose of this study was to explore the role of HPV subtypes not covered by the nine-valent vaccine in high-grade cervical precancerous lesions and cervical cancer.

MATERIALS AND METHODS

A retrospective analysis was performed on the clinical data of 5220 patients with an HPV infection who were diagnosed and treated in the Department of Gynecology of Shanghai General Hospital between October 2016 and February 2020. In addition, the clinical characteristics of the biopsy results of 470 cases of cervical intraepithelial neoplasia (CIN) 2-3 and 205 cases of cervical squamous cell carcinoma were analyzed.

RESULTS

Among patients with HPV subtype infection not covered by the nine-valent vaccine, univariate analysis showed that compared with patients with CIN 2-3, age ≥ 50, not using condom and TCT reported as ASC-H were risk factors for cervical squamous cell carcinoma (P < 0.05). The detection rates of HPV subtype not covered by the nine-valent vaccine in CIN 2-3 and cervical squamous cell carcinoma patients were 7.23% and 6.34%, respectively.

CONCLUSION

In patients with CIN 2-3 and cervical squamous cell carcinoma, the infection rates of HPV subtype not covered by the nine-valent vaccine were 7.23% and 6.34%, respectively. With the increasing popularity of the vaccine, the infection rates of the corresponding HPV subtype decreased; however, HPV subtype infection not covered by the nine-valent vaccine should not be ignored.

Target-Dependent Gating of Nanopores Integrated with H-Cell: Toward A General Platform for Photoelectrochemical Bioanalysis

Herein we present a proof-of-concept study of target-dependent gating of nanopores for general photoelectrochemical (PEC) bioanalysis in an H-cell. The model system was constructed upon a left chamber containing ascorbic acid (AA), the antibody modified porous anodic alumina (AAO) membrane separator, and a right chamber placed with the three-electrode system. The sandwich immunocomplexation and the associated enzymatic generation of biocatalytic precipitation (BCP) in the AAO nanopores would regulate the diffusion of AA from the left cell to the right cell, leading to a varied photocurrent response of the ZnInS nanoflakes photoelectrode. Exemplified by fatty-acid-banding protein (FABP) as the target, the as-developed protocol achieved good performance in terms of sensitivity, selectivity, reproducibility, as well as efficient reutilization of the working electrode. On the basis of an H-cell, this work features a new protocol of target-dependent gating-based PEC bioanalysis, which can serve as a general PEC analytical platform for various other targets of interest.

Enhanced high temperature ferromagnetism in Bi1-xRxFeO3(R= Dy, Y) compounds

In this work we report experimental evidence for the weak high-temperature ferromagnetism in Bi1-xRxFeO3(R= Dy, Y) compounds by systematic characterizations, excluding the possible side-effects from other iron-based impurities. Remarkable saturated magnetic moment was observed in the Y-substituted samples, Bi1-xYxFeO3, which is larger than the moment obtained in Bi1-xDyxFeO3, the Dy-substituted samples with antiferromagnetic background. The physical origin of the weak ferromagnetic transition is discussed and serious lattice distortions have been identified based on the x-ray diffraction and Raman scattering data, although the rhombohedral structure symmetry remains unchanged upon the substitutions. It is believed that the structural distortion suppressed cycloid spin structure is the main factor for the enhanced magnetization in Bi1-xRxFeO3compounds. Additionally, the Dy3+-Fe3+antiferromagnetic coupling, which strengthens the antiferromagnetic interaction in Bi1-xDyxFeO3compounds, acts as the driving force for the magnetic discrepancy between Bi1-xYxFeO3and Bi1-xDyxFeO3samples.

Establishing Interfacial Charge-Transfer Transitions on Ferroelectric Perovskites: An Efficient Route for Photoelectrochemical Bioanalysis

This work presents the concept of establishing interfacial charge-transfer transitions (ICTT) on ferroelectric perovskites for efficient photoelectrochemical (PEC) bioanalysis. The model system was exemplified by using representative lead titanate (PbTiO₃) and an enzyme tandem consisting of the isocitrate dehydrogenase (ICDH) and p-hydroxybenzoate hydroxylase (PHBH). The enzymatic generation of protocatechuic acid (PCA) can coordinate onto the surface of the PbTiO₃ and hence form the ICTT that enables direct ligand-to-metal charge transfer from the highest occupied molecular orbital (HOMO) of PCA to the conduction band (CB) of PbTiO₃ under light irradiation. Due to the ferroelectric polarization induced electric field of PbTiO₃ and the surface polarity of PCA modification, enhanced charge separation of the ICTT contributes to the generation of anodic photocurrent and thus underlies a unique route for detecting the enzymatic activity or its substrate. For dehydrogenase detection, this strategy has better performance than some classical methodologies in terms of high sensitivity and improved selectivity. This work not only features ICTT establishment on ferroelectric perovskites for unique bioanalysis but also provides new insights into the utilization of ferroelectric perovskites for advanced PEC bioanalysis.

Ethnic Disparities in Dental Caries among Adolescents in China

Comprehensive research on ethnic disparities in dental caries in China is limited. The aims of this cross-sectional study were to compare the levels of dental caries in adolescents between the Han ethnic group and ethnic minority groups in China and to explore the risk indicators for dental caries within ethnic subgroups. Data from the Fourth National Oral Health Survey in 2015, which covered all 31 province-level administrative divisions in mainland China, were used. The dental caries status in the permanent dentition of adolescents aged 12, 13, 14, and 15 y was measured using the decayed, missing, and filled teeth (DFMT) score, and sociodemographic characteristics and oral health-related behaviors were also collected. A total of 118,601 adolescents were included, with ethnic minority groups accounting for 13.15%. Of the Han and minority groups, the standardized prevalence of dental caries experience was 40.58% and 47.67%, and the mean DMFT scores were 0.97 and 1.28, respectively. According to the multivariate zero-inflated negative binomial regression analysis, the caries status of minorities was more severe than Han adolescents (adjusted prevalence rate ratio [PRR], 1.14; 95% confidence interval [CI], 1.10-1.18). This disparity was greater among adolescents who lived in rural areas, had mid-level economic status, and frequently consumed sugary beverages. After propensity score matchings, Uygur (PRR, 1.44; 95% CI, 1.25-1.67), Tibetan (PRR, 1.39; 95% CI, 1.3-1.48), and Yi (PRR, 1.24; 95% CI, 1.04-1.48) adolescents were significantly more likely to have caries than Han adolescents. Subgroup analyses revealed that gender, age, location of residence, economic status, region, consumption of sweet snacks and sugary beverages, and dental visit pattern were significantly associated with dental caries within ethnic minorities.

[Surgical treatment of total subclavian artery occlusion: a single center experience of 67 cases]

Objective: To examine the outcomes of surgical repair for patients with total subclavian artery occlusion. Methods: A retrospective analysis was performed on 67 patients with subclavian artery occlusion disease admitted at Ward 1 of Aortic and Vascular Surgery Center, Fuwai Hospital from January 2016 to July 2019. The age was, and There were 51 male patients and 16 females with an age of (61.7±8.2) years (range: 37 to 79 years). The t-test, Mann-Whitney U-test, χ(2) test, and Fisher's exact test were used to analyze the factors related to the technique success. The Kaplan-Meier curve was used to calculate the cumulative patency rate and plot the corresponding survival curves, and the Log-rank test was used for comparison. The length from the subclavian artery ostial to the occlusion area was used as a variable to plot the receiver operating characteristic curve, and the optimal cut-off value was determined by the Youden index. Results: Eighteen patients received open surgery. Forty-nine patients with subclavian artery occlusion accepted endovascular repair, of which 38 patients succeeded (31 cases on left side and 3 cases on right side). Fifteen patients failed with endovascular therapy, of which 10 cases received elective surgery and 5 cases received conservative therapy. The success rate of endovascular repair was 69.4%(34/49). Among them, the success rate of left subclavian artery occlusion was 81.6%(31/38), while the right side was 3/11. Patients with the length from the subclavian artery ostial to the occlusion area ≥6 mm were more likely to get success (23/34 vs. 4/15, χ(2)=5.506, P=0.019). In the endo-group, one patient had hemorrhage in the left chest. In the open-group, one patient had lymphatic leakage. Follow-up period ranged from 3 to 46 months with a median of 22 months. The patency of endovascular repair group and the open surgery group was 92.6% and 90.8% at 12-month, while 82.9% and 84.3% at 24-month, respectively. The cumulative patency rates of smoking patients and non-smoking patients after endovascular treatment were 70.2% vs. 100% (P=0.048) at 24-month. No independent prognosis factors were identified through the Cox proportional risk model which significantly affected postoperative patency rates for patients with subclavian artery occlusion. Conclusions: Part of patients with subclavian artery occlusion can be treated by endovascular therapy. The success rate of left subclavian artery occlusions is higher than right sides. The length from the subclavian artery ostial to the occlusion area affected the success rate of repair.

[Construction of apoptosis-stimulating of p53 protein 2 gene knockout mice and its effect on diethylnitrosamine-induced liver cancer]

Objective: To construct apoptosis-stimulating of p53 protein 2 (ASPP2) gene knockout mice using diethylnitrosamine (DEN)-induced liver cancer model to study the biological functions of ASPP2. Methods: The sgRNA oligonucleotides were constructed, and ASPP2 knockout mice were prepared with the CRISPR/Cas9 system. PCR and sequencing methods were used to identify the genotypes of F0 and F1 generations and their progeny. DEN was used to induce ASPP2+/- mice to establish liver cancer model. Results: PCR and sequencing results showed that ASPP2 gene was successfully knocked out in F0 generation mice. The genotype of F1 generation mice was accorded with ASPP2+/- and had obtained stable heredity. The success rate of DEN-induced liver cancer model (7/8 and 3 / 8) of ASPP2 + /-mice obtained by self-hybridization of F1 generation was significantly higher than that of wild-type mice. Conclusion: ASPP2 knockout mice were successfully constructed based on the CRISPR/Cas9 system. The success rate of DEN-induced liver cancer model of ASPP2 knockout mice was significantly higher than that of the wild-type mice.

[Prognostic value of Montreal Cognitive Assessment in heart failure patients]

Objective: To explore the occurrence of cognitive impairment in Chinese heart failure (HF) patients and it's impact on prognosis. Methods: In this prospective observational study, a total of 990 HF patients were enrolled from 24 hospitals in China during December 2012 to November 2014. All patients were administrated with the interview-format Montreal Cognitive Assessment (MoCA), according to which they were divided into MoCA<26 (with cognitive impairment) group and MoCA≥26 (without cognitive impairment) group. Baseline data were collected and a 1-year follow up was carried out. Univariate and multivariate logistic or Cox regression were performed for 1-year outcomes. Results: Cognitive impairment was evidenced in 628 patients (63.4%) and they were more likely to be older, female, and with higher proportion of New York Heart Association(NYHA) class Ⅲ-Ⅳ, chronic obstructive pulmonary disease (COPD), ischemic heart disease, while body mass index (BMI), education level, and medical insurance rate were lower (all P<0.05) as compared to patients in MoCA≥26 group. The rate of percutaneous intervention, device implantation, cardiac surgery and evidence-based medications were significantly lower in MoCA<26 group than in MoCA≥26 group (all P<0.05). During the 1-year follow up, patients in the MoCA<26 group had higher all-cause mortality (10.2%(64/628) vs. 2.2%(8/362), P<0.01), cardiovascular mortality (5.9%(37/628) vs. 0.8%(3/362), P<0.01) and major adverse cardiac and cerebrovascular events (MACCE) (9.6%(60/628) vs. 2.5%(8/362), P<0.01) than patients in the MoCA≥26 group. In univariate regression, MoCA<26 was associated with increased all-cause mortality (HR(95%CI):4.739(2.272-9.885), P<0.01), cardiovascular mortality (HR(95%CI):7.258(2.237-23.548), P=0.001) and MACCE (OR(95%CI):4.143(2.031-8.453), P<0.01). After adjustment by multivariate regression, MoCA<26 was indicated as an independent risk factor for all-cause mortality (HR(95%CI): 6.387(2.533-16.104), P<0.01), cardiovascular mortality (HR(95%CI): 10.848(2.586-45.506), P=0.001) and MACCE (OR(95%CI): 4.081(1.299-12.816), P=0.016), while not for re-hospitalization for HF (OR(95%CI):1.010(0.700-1.457), P=0.957). Conclusions: Cognitive impairment is common in HF patients,and it is an independent prognostic factor for 1-year outcomes. Routine cognitive function assessment and active intervention are thus recommended for HF patients.

Three-dimensional CdS nanosheet-enwrapped carbon fiber framework: Towards split-type CuO-mediated photoelectrochemical immunoassay

This work reports a customized methodology for the fabrication of 3D CdS nanosheet (NS)-enwrapped carbon fiber framework (CFF) and its utilization for sensitive split-type CuO-mediated PEC immunoassay. Specifically, the 3D CdS NS-CFF was fabricated via a solvothermal process, while the sandwich immunocomplexing was allowed in a 96 well plate with CuO nanoparticles (NPs) as the signaling labels. The subsequent release of the Cu²⁺ ions was directed to interact with the CdS NS, generating trapping sites and thus inhibiting its photocurrent generation. In such a protocol, the 3D CdS NS-CFF photoelectrode could not only guarantee its sufficient contact with the Cu²⁺-containing solution but also supply plenty CdS surface for the Cu²⁺ ions. Because of the target-dependent release of the Cu²⁺ ions and its proper coupling with the 3D CdS NS-CFF photoelectrode, a sensitive split-type PEC immunoassay was achieved for the detection of brain natriuretic peptide (BNP). This proposed system exhibited good stability and selectivity, and its applicability for real sample analysis was also demonstrated via comparison with the commercial BNP enzyme-linked immunosorbent assay (ELISA) kit. We expect this work could stimulate more interest in the design and utilization of 3D photoelectrodes for novel PEC bioanalysis.

Cepharanthine, a bisbenzylisoquinoline alkaloid, inhibits lipopolysaccharide-induced microglial activation

Activation of microglial cells in the brain has been considered to be associated with various neurodegenerative diseases (NDD). In this study, cepharanthine, a bisbenzylisoquinoline alkaloid, was found to inhibit lipopolysaccharide (LPS)-induced microglial activation. Cepharanthine suppressed the release of nitric oxide (NO) by LPS-activated primary mouse cortical microglia and/or BV2 microglial cell line. Cepharanthine reduced LPS-induced mRNA expression of inducible NO synthase (iNOS), but it did not display direct NO-scavenging activity up to 100 μM in sodium nitroprusside (SNP) solution. Further studies revealed that cepharanthine suppressed the release of cytokines (TNF-α, IL-1β, and IL-6) by LPS-activated microglial cells. Cepharanthine may have potential in the treatment of neurodegenerative diseases accompanied by microglial activation.

[Features of a modified WHO/UCLA AVLT performance in amnestic mild cognitive impairment and mild Alzheimer's disease]

Objective: To compare the features of a modified WHO/UCLA AVLT performance in the cognitive normal, amnestic mild cognitive impairment (aMCI) and mild Alzheimer's disease (mild AD) patients. Method: A total of 105 cases of cognitivenormal (CN), 48 aMCI and 50 mild AD patients were included between 2016 and 2018. All subjects undertook detailed neuropsychological tests and brain MRI/CT scan. Results: The total score of five learning trials in CN, aMCI and AD groups were 53.9±6.9, 34.6±8.3 and 23.7±6.2, respectively (P<0.001). The score of 20-min delay recallwere 12.5±1.6, 4.3±3.0 and 0.6±1.0, respectively (P<0.001) in three groups. The score of cued recall were 13.0±1.4, 7.0±2.4 and 2.6±2.0, respectively (P<0.001). The score of 20-min delay recall had the largest effect sizes between CN and aMCI groups (Cohen'd=3.8, 95%CI,3.3-4.4), and CN and mild AD groups (Cohen'd=8.1, 95%CI 7.1-9.1). Cued recall had the largest effect size between aMCI and mild AD groups (Cohen'd=2.04, 95%CI 1.5-2.5). The scores of learning total score, 20-min delay recall, cued recall and recognition had the strong relationships with the scores of mini-mental state examination (MMSE) and Montreal cognitive assessment (MoCA) , but obtaining moderate relationships with Boston naming test and trail making test (TMT) and weak relationships with digit span and figure copy. Age and education had no relationship with the main indices of this modified AVLT. Conclusions: The modified WHO/UCLA AVLT is still an age and education fair test to assess memory domain function. Qualitative analysis of AVLT profiles may be useful to differentiate the CN, aMCI and mild AD in Chinese sample.

[Combined detection of KRAS, NRAS, BRAF and PIK3CA mutations in the plasma and tumor tissues of colorectal cancer patients]

Objective: To analyze the concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations detected in plasma and matched tumor tissues in colorectal cancer patients, in order to provide good evidences to support plasma could be a potential surrogate of tumor tissue for gene mutation test. Methods: One hundred and seventy-five cases of colorectal cancer were collected at the First Hospital of Jilin University, from October 2016 to October 2017.There were 101 males and 74 females, their ages ranged from 28 to 85 years,with median age of 59 years. The KRAS, NRAS, BRAF and PIK3CA gene mutations in the plasma and paired tumor specimens of all patients were detected by next generation sequencing. Results: The results of tissue samples test were gold standard. Comparison of the four genes showed that concordance rates between plasma and tissue samples were 81.1%(Kappa=0.543), 99.4%(Kappa=0.886), 99.4% (Kappa=0.886) and 97.7%(Kappa=0.714) respectively for KRAS, NRAS, BRAF and PIK3CA. The plasma detection rates of these genes were related to tumor stage(P=0.001), but not to gender(P=0.468) and age(P=1.000) of patients. Conclusions: The study shows a high concordance of KRAS, NRAS, BRAF and PIK3CA gene mutations in plasma against mutation status in tumor tissue. In colorectal cancer, tumor tissue remains the best specimen for gene detection. However, patients from tumor tissue specimens cannot be obtained, especially those with advanced metastases, plasma can be used instead of tissue to detect the mutation status of KRAS, NRAS, BRAF and PIK3CA to guide targeted therapy.

Sex Recognition of Skulls in Chinese Uygur

Abstract

Objective Logistic regression method was used to establish a multiple regression sex discriminant function to discriminate the complete skull model and the incomplete skull model without frontal bone, occipital bone and mandible of Uygur adults in Turpan, Xinjiang. Methods A total of 117 （60 male and 57 female） three-dimensional skull models were collected by CT. Sixteen cranial measurement indexes were measured and calculated by computer software. The multivariate regression sex discriminant function was established with Logistic regression method and retrospectively tested. Results Among the 16 measurement indexes, except for nose width （x₇） and maximum frontal breadth （x₁₃）, the remaining 14 indexes had statistical significance of differences between male and female （P<0.05）. For the discriminant function of complete skull established by eyebrow arch convexity （x₄）, mastoid width （x₆）, maximum cranial length （x₁₂）, cranial base length （x₁₅）, cranial circumference （x₁₆）, the male and female discrimination accuracy was 90.0% and 94.7%, respectively. For the sex discriminant function of incomplete skull without frontal bone established by mandibular angle width （x₁₀）, mandibular height （x₁₁） and cranial circumference （x₁₆）, the discrimination accuracy of male and female was 85.0% and 84.2%, respectively. For the sex discriminant function of incomplete skull without occipital bone established by the index of eyebrow arch convexity （x₄）, the discrimination accuracy of male and female was 80.0% and 73.7%, respectively. For the sex discriminant function of incomplete skull without mandible established by frontal chord （x₅） and occipital protrusion angle （x₉）, the discrimination accuracy of male and female was 85.0% and 78.9%, respectively. Conclusion The computer software and system developed in our study can achieve sex discrimination of complete skulls and incomplete skulls without frontal bone, occipital bone or mandible.

Wave propagation in tunable lightweight tensegrity metastructure

Lightweight metastructures are designed consisting of prismatic tensegrity building blocks which have excellent strength-to-weight ratio and also enable unique compression-torsion coupling. A theoretical model with a coupled axial-torsional stiffness is first developed to study the band structures of the proposed lightweight metastructures. Then, various unit cell designs are investigated for bandgap generations at desired frequency ranges. Broadband full-wave attenuation is found in the tensegrity metastructure with special opposite-chirality. Furthermore, tunable stiffness in the prismatic tensegrity structure is investigated and 'small-on-large' tunability is achieved in the metastructure by harnessing the geometrically nonlinear deformation through an external control torque. Prestress adjustment is also investigated for fine tuning of the band structure. Finally, frequency response tests on the finite metastructures are preformed to validate their wave attenuation ability as well as their wave propagation tunability. The proposed tensegrity metastructures could be very useful in various engineering applications where lightweight and tunable structures with broadband vibration suspension and wave attenuation ability are in high demand.

[Status and analysis of oral disease burden: comparison of the domestic and overseas data]

At present, it has been regarded that oral disease was one of the most prevalent problems for people's general health around the world. Oral disease burden study focuses on the pressure and effect of oral diseases to the whole social economy and people's health. Oral disease burden, as a public health problem, needs to be attached importance in China and foreign countries. By means of retrieving the literature, this review article summarizes the progress of domestic and oversea studies on oral disease burden, analyses the epidemiological burden through the indicators such as the prevalence rate, decayed missing and filled teeth, disability adjusted life years, disability weights, and illustrates the economic burden of oral diseases by using part of the data. Results shows that the oral disease burden is obvious in most countries and regions both in China and foreign countries. The study of oral disease burden in China has not been well developed. Giving priority to dental caries, periodontal disease and tooth loss, the prevalence of oral diseases in China is high. The rate of seeking dental treatments is low and the proportion of self-supporting treatments is high. In general, the epidemiological and economic burden of oral diseases is heavier in China than that in the rest of the world.

[Study on the classification of dominant pathogens related to febrile respiratory syndrome, based on the method of Bayes discriminant analysis]

Objective: To understand the dominant pathogens of febrile respiratory syndrome (FRS) patients in Gansu province and to establish the Bayes discriminant function in order to identify the patients infected with the dominant pathogens. Methods: FRS patients were collected in various sentinel hospitals of Gansu province from 2009 to 2015 and the dominant pathogens were determined by describing the composition of pathogenic profile. Significant clinical variables were selected by stepwise discriminant analysis to establish the Bayes discriminant function. Results: In the detection of pathogens for FRS, both influenza virus and rhinovirus showed higher positive rates than those caused by other viruses (13.79%, 8.63%), that accounting for 54.38%, 13.73% of total viral positive patients. Most frequently detected bacteria would include Streptococcus pneumoniae, and haemophilus influenza (44.41%, 18.07%) that accounting for 66.21% and 24.55% among the bacterial positive patients. The original-validated rate of discriminant function, established by 11 clinical variables, was 73.1%, with the cross-validated rate as 70.6%. Conclusion: Influenza virus, Rhinovirus, Streptococcus pneumoniae and Haemophilus influenzae were the dominant pathogens of FRS in Gansu province. Results from the Bayes discriminant analysis showed both higher accuracy in the classification of dominant pathogens, and applicative value for FRS.

[Effect of febuxostat on epithelial-to-mesenchymal transition of kidney tubules, serum interleukin-6 and transforming growth factor β(1) in hyperuricemic rats]

Objective: To observe the effect of febuxostat on epithelial-to-mesenchymal transition (EMT) of kidney tubules and the levels of serum IL-6 nad transforming growth factor (TGF)β(1) in hyperuricemic rats. Methods: Forty male SD rats were divided into 4 groups: normal control group (NC group), oteracil potassium group (OP group), oteracil potassium with febuxostat group (OF group) and oteracil potassium with benzbromarone group (OB group). Each group had 10 rats and balanced in body weights. To induce hyperuricemia, rats were given oteracil potassium by gastric gavage once a day for eight weeks. Rats in OF group and OB group were given either febuxostat or benbromarone starting with oteracil potassium, and rats in NC group was given saline only. Blood samples were taken before, and at the end of 4 and 8 weeks of the treatments and serum uric acid, creatinine, blood usea nitrogen(BUN), IL-6 and TGFβ(1) contents were measured at each time point. Renal pathological changes were observed via HE and Masson staining, and the expression of α-SMA and E-cadherin were detected by immunohistochemistry. Results: Compared with those in NC group, the levels of serum uric acid, creatinine, BUN, IL-6 and TGFβ(1) in the another three groups were increased significantly (all P<0.01). However, the IL-6 and TGFβ(1) contents in OF group were much lower than those in OP group (P<0.01). HE and Masson staining showed that OF group had less damage and tubulointerstitial fibrosis than OP group and OB group (P<0.01). Moreover, the expression of α-SMA was significantly down-regulated (P<0.01) and that of E-cadherin was significantly up-regulated in OF group compared with those in OP group. Conclusion: Febuxostat treatment significantly inhibited EMT and reduced the levels of IL-6 and TGFβ(1) in hyperuricemia rats.

[Evaluation of estimation of prevalence ratio using bayesian log-binomial regression model]

To evaluate the estimation of prevalence ratio (PR) by using bayesian log-binomial regression model and its application, we estimated the PR of medical care-seeking prevalence to caregivers' recognition of risk signs of diarrhea in their infants by using bayesian log-binomial regression model in Openbugs software. The results showed that caregivers' recognition of infant' s risk signs of diarrhea was associated significantly with a 13% increase of medical care-seeking. Meanwhile, we compared the differences in PR's point estimation and its interval estimation of medical care-seeking prevalence to caregivers' recognition of risk signs of diarrhea and convergence of three models (model 1: not adjusting for the covariates; model 2: adjusting for duration of caregivers' education, model 3: adjusting for distance between village and township and child month-age based on model 2) between bayesian log-binomial regression model and conventional log-binomial regression model. The results showed that all three bayesian log-binomial regression models were convergence and the estimated PRs were 1.130(95%CI: 1.005-1.265), 1.128(95%CI: 1.001-1.264) and 1.132(95%CI: 1.004-1.267), respectively. Conventional log-binomial regression model 1 and model 2 were convergence and their PRs were 1.130(95% CI: 1.055-1.206) and 1.126(95% CI: 1.051-1.203), respectively, but the model 3 was misconvergence, so COPY method was used to estimate PR, which was 1.125 (95%CI: 1.051-1.200). In addition, the point estimation and interval estimation of PRs from three bayesian log-binomial regression models differed slightly from those of PRs from conventional log-binomial regression model, but they had a good consistency in estimating PR. Therefore, bayesian log-binomial regression model can effectively estimate PR with less misconvergence and have more advantages in application compared with conventional log-binomial regression model.

[Ventilator-associated pneumonia among premature infants <34 weeks' gestational age in neonatal intensive care unit in China: a multicenter study]

Objective: To investigate the incidence and pathogen distribution of ventilator-associated pneumonia (VAP) among preterm infants admitted to level Ⅲ neonatal intensive care units (NICU) in China. Method: A prospective study was conducted in 25 level Ⅲ NICU, enrolling all preterm infants <34 weeks gestational age admitted to the participating NICU within the first 7 days of life from May 2015 to April 2016. Chi-square test, t test and Mann-Whitney U test were used for statistical analysis. Result: A total of 7 918 patients were enrolled, within whom 4 623(58.4%) were males. The birth weight was (1 639±415) g and the gestational age was (31.4±2.0) weeks; 4 654(58.8%) infants required non-invasive mechanical ventilation and 2 154(27.2%) required intubation. Of all the mechanically ventilated patients, VAP occurred in 95 patients. The overall VAP rate was 7.0 episodes per 1 000 ventilator days, varying from 0 to 34.4 episodes per 1 000 ventilator days in different centers. The incidence of VAP was 9.6 and 6.0 per 1 000 ventilator days in children's hospitals and maternity-infant hospitals respectively, without significant differences (t=1.002, P=0.327). Gram-negative bacilli (76 strains, 91.6%) were the primary VAP microorganisms, mainly Acinetobacter baumannii (24 strains, 28.9%), Klebsiella pneumonia (23 strains, 27.7%), and Pseudomonas aeruginosa (10 strains, 12.0%). Conclusion: The incidence of VAP in China is similar to that in developed counties, with substantial variability in different NICU settings. More efforts are needed to monitor and evaluate the preventable factors associated with VAP and conduct interventions that could effectively reduce the occurrence of VAP.

Yeast one-hybrid screening the potential regulator of CYP6B6 overexpression of Helicoverpa armigera under 2-tridecanone stress

In insect, the cytochrome P450 plays a pivotal role in detoxification to toxic allelochemicals. Helicoverpa armigera can tolerate and survive in 2-tridecanone treatment owing to the CYP6B6 responsive expression, which is controlled by some regulatory DNA sequences and transcription regulators. Therefore, the 2-tridecanone responsive region and transcription regulators of the CYP6B6 are responsible for detoxification of cotton bollworm. In this study, we used yeast one-hybrid to screen two potential transcription regulators of the CYP6B6 from H. armigera that respond to the plant secondary toxicant 2-tridecanone, which were named Prey1 and Prey2, respectively. According to the NCBI database blast, Prey1 is the homology with FK506 binding protein (FKBP) of Manduca sexta and Bombyx mori that belongs to the FKBP-C superfamily, while Prey2 may be a homology of an unknown protein of Papilio or the fcaL24 protein homology of B. mori. The electrophoretic mobility shift assays revealed that the FKBP of prokaryotic expression could specifically bind to the active region of the CYP6B6 promoter. After the 6th instar larvae of H. armigera reared on 2-tridecanone artificial diet, we found there were similar patterns of CYP6B6 and FKBP expression of the cotton bollworm treated with 10 mg g-1 2-tridecanone for 48 h, which correlation coefficient was the highest (0.923). Thus, the FKBP is identified as a strong candidate for regulation of the CYP6B6 expression, when the cotton bollworm is treated with 2-tridecanone. This may lead us to a better understanding of transcriptional mechanism of CYP6B6 and provide very useful information for the pest control.

Identification of the 2-tridecanone responsive region in the promoter of cytochrome P450 CYP6B6 of the cotton bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae)

Eukaryote transcription is controlled by regulatory DNA sequences and transcription factors, so transcriptional control of gene plays a pivotal role in gene expression. In this study, we identified the region of the CYP6B6 gene promoter of Helicoverpa armigera which responds to the plant secondary toxicant 2-tridecanone. Transient transfection assay results from five of stepwise deletion fragments linked to the luciferase reporter gene revealed that the promoter activity of each CYP6B6 fragment was significantly higher than that of their basal activity after the Sf9 cells were treated with 2-tridecanone. Among all, the fragment spanning -373 to +405 bp of the CYP6B6 promoter showed an obviously 2-tridecanone inducibility (P<0.0001), which might have the 2-tridecanone responsive element based on promoter activity. Electrophoretic mobility shift assays revealed that the nuclear protein extracted from midgut of the 6th instar larva of H. armigera, reared on 10 mg 2-tridecanone per gram artificial diet for 48 h, could specifically bind to the active region from -373 to 21 bp of the CYP6B6 promoter. The combination feature also appeared when using a shorter fragment from -292 to -154 bp of the CYP6B6 promoter. Taken together, we found a 2-tridecanone core responsive region between -292 and -154 bp of the CYP6B6 promoter. This may lead us to a better understanding of transcriptional mechanism of P450 gene and provide very useful information for the pest control.

Characterization and expression analysis of six chitinase genes from the desert beetle Microdera punctipennis in response to low temperature

BACKGROUND

Chitinase is responsible for chitin metabolism in a wide range of organisms. However, current knowledge on insect chitinase and their possible functions in relation to low temperature stress is very limited.

OBJECTIVE

Six chitinase genes from cold treated desert beetle Microdera punctipennis obtained by RNA-seq technology were characterized, and their expression patterns in different tissues and in response to cold were investigated.

METHODS

Multiple sequence alignment was carried out using ClustalW1.81 and Phylogenetic trees were generated by MEGA5. The expression patterns were studied by quantitative real-time PCR.

RESULTS

These genes were belong to three different chitinase groups. Almost all of them were highly expressed in midgut, and some are expressed in fat body or hindgut. Subzero-4 degree C had stronger effect than 4 degree C in inducing chitinase expression.

CONCLUSION

The tissue specific and cold inducible expressions suggest that the chitinases may have diverse functions and play roles in insect cold adaptation.

Micropolar continuum modelling of bi-dimensional tetrachiral lattices

The in-plane behaviour of tetrachiral lattices should be characterized by bi-dimensional orthotropic material owing to the existence of two orthogonal axes of rotational symmetry. Moreover, the constitutive model must also represent the chirality inherent in the lattices. To this end, a bi-dimensional orthotropic chiral micropolar model is developed based on the theory of irreducible orthogonal tensor decomposition. The obtained constitutive tensors display a hierarchy structure depending on the symmetry of the underlying microstructure. Eight additional material constants, in addition to five for the hemitropic case, are introduced to characterize the anisotropy under Z₂ invariance. The developed continuum model is then applied to a tetrachiral lattice, and the material constants of the continuum model are analytically derived by a homogenization process. By comparing with numerical simulations for the discrete lattice, it is found that the proposed continuum model can correctly characterize the static and wave properties of the tetrachiral lattice.

Effects of isobutyrate supplementation on ruminal microflora, rumen enzyme activities and methane emissions in Simmental steers

The objective of this study was to evaluate the effects of isobutyrate supplementation on rumen microflora, enzyme activities and methane emissions in Simmental steers consuming a corn stover-based diet. Eight ruminally cannulated Simmental steers were used in a replicated 4 × 4 Latin square experiment. The treatments were control (without isobutyrate), low isobutyrate (LIB), moderate isobutyrate (MIB) and high isobutyrate (HIB) with 8.4, 16.8 and 25.2 g isobutyrate per steer per day respectively. Isobutyrate was hand-mixed into the concentrate portion. Diet consisted of 60% corn stover and 40% concentrate [dry matter (DM) basis]. Dry matter intake (averaged 9 kg/day) was restricted to a maximum of 90% of ad libitum intake. Population of total bacteria, cellulolytic bacteria and anaerobic fungi were linearly increased, whereas that of protozoa and total methanogens was linearly reduced with increasing isobutyrate supplementation. Real-time PCR quantification of population of Ruminococcus albus, Ruminococcus flavefaciens, Butyrivibrio fibrisolvens and Fibrobacter succinogenes was linearly increased with increasing isobutyrate supplementation. Activities of carboxymethyl cellulase, xylanase and β-glucosidase were linearly increased, whereas that of protease was linearly reduced. Methane production was linearly decreased with increasing isobutyrate supplementation. Effective degradabilities of cellulose and hemicellulose of corn stover were linearly increased, whereas that of crude protein in diet was linearly decreased with increasing isobutyrate supplementation. The present results indicate that isobutyrate supplemented improved microflora, rumen enzyme activities and methane emissions in steers. It was suggested that the isobutyrate stimulated the digestive micro-organisms or enzymes in a dose-dependent manner. In the experimental conditions of this trial, the optimum isobutyrate dose was approximately 16.8 g isobutyrate per steer per day.

[Research on relevance between macroscopic feature individual differences and quality of Gansu cultivated Angelica sinensis]

OBJECTIVE

To analyze the appearance differences of Gansu cultivated Angelica sinensis, and explore the relevance between the appearance differences and quality.

METHODS

The macroscopic feature of 22 batches of Angelica sinensis from different habitats was measured as index. The content of ferulic acid, volatile oil and extract were determined by the method recorded in the Chinese Pharmacopoeia. The data were analyzed by SPSS 15.0 software.

RESULTS

The habitat was positively correlated with the index. Indexes of nine groups had direct correlation with each other. The habitat was significantly correlated with other indexes except the length of the head. The extract and ferulic acid were positively correlated with habitat and index. Extract had significant correlation with macroscopic feature. Ferulic acid only had significant correlation with head length. The volatile oil only had significant correlation with habitat and no significant correlation with index. Root weight and number of lateral roots had obvious difference in different habitat which coefficient of variation was 44.1% and 28.6%, respectively.

CONCLUSION

There are significant individual differences in Angelica sinensis. The chemical composition has a certain correlation with macroscopic feature. Angelica sinensis cultivation needs to consider the choice of habitat.

Enhancing the bioactivity of Poly(lactic-co-glycolic acid) scaffold with a nano-hydroxyapatite coating for the treatment of segmental bone defect in a rabbit model

PURPOSE

Poly(lactic-co-glycolic acid) (PLGA) is excellent as a scaffolding matrix due to feasibility of processing and tunable biodegradability, yet the virgin scaffolds lack osteoconduction and osteoinduction. In this study, nano-hydroxyapatite (nHA) was coated on the interior surfaces of PLGA scaffolds in order to facilitate in vivo bone defect restoration using biomimetic ceramics while keeping the polyester skeleton of the scaffolds.

METHODS

PLGA porous scaffolds were prepared and surface modification was carried out by incubation in modified simulated body fluids. The nHA coated PLGA scaffolds were compared to the virgin PLGA scaffolds both in vitro and in vivo. Viability and proliferation rate of bone marrow stromal cells of rabbits were examined. The constructs of scaffolds and autogenous bone marrow stromal cells were implanted into the segmental bone defect in the rabbit model, and the bone regeneration effects were observed.

RESULTS

In contrast to the relative smooth pore surface of the virgin PLGA scaffold, a biomimetic hierarchical nanostructure was found on the surface of the interior pores of the nHA coated PLGA scaffolds by scanning electron microscopy. Both the viability and proliferation rate of the cells seeded in nHA coated PLGA scaffolds were higher than those in PLGA scaffolds. For bone defect repairing, the radius defects had, after 12 weeks implantation of nHA coated PLGA scaffolds, completely recuperated with significantly better bone formation than in the group of virgin PLGA scaffolds, as shown by X-ray, Micro-computerized tomography and histological examinations.

CONCLUSION

nHA coating on the interior pore surfaces can significantly improve the bioactivity of PLGA porous scaffolds.

[Simulation of vegetation indices optimizing under retrieval of vegetation biochemical parameters based on PROSPECT + SAIL model]

This study analyzed the sensitivities of three vegetation biochemical parameters [chlorophyll content (Cab), leaf water content (Cw), and leaf area index (LAI)] to the changes of canopy reflectance, with the effects of each parameter on the wavelength regions of canopy reflectance considered, and selected three vegetation indices as the optimization comparison targets of cost function. Then, the Cab, Cw, and LAI were estimated, based on the particle swarm optimization algorithm and PROSPECT + SAIL model. The results showed that retrieval efficiency with vegetation indices as the optimization comparison targets of cost function was better than that with all spectral reflectance. The correlation coefficients (R2) between the measured and estimated values of Cab, Cw, and LAI were 90.8%, 95.7%, and 99.7%, and the root mean square errors of Cab, Cw, and LAI were 4.73 microg x cm(-2), 0.001 g x cm(-2), and 0.08, respectively. It was suggested that to adopt vegetation indices as the optimization comparison targets of cost function could effectively improve the efficiency and precision of the retrieval of biochemical parameters based on PROSPECT + SAIL model.

Effects of reed straw, zeolite, and superphosphate amendments on ammonia and greenhouse gas emissions from stored duck manure

Stored poultry manure can be a significant source of ammonia (NH) and greenhouse gases (GHGs), including nitrous oxide (NO), methane (CH), and carbon dioxide (CO) emissions. Amendments can be used to modify physiochemical properties of manure, thus having the potential to reduce gas emissions. Here, we lab-tested the single and combined effects of addition of reed straw, zeolite, and superphosphate on gas emissions from stored duck manure. We showed that, over a period of 46 d, cumulative NH emissions were reduced by 61 to 70% with superphosphate additions, whereas cumulative NO emissions were increased by up to 23% compared with the control treatment. Reed straw addition reduced cumulative NH, NO, and CH emissions relative to the control by 12, 27, and 47%, respectively, and zeolite addition reduced cumulative NH and NO emissions by 36 and 20%, respectively. Total GHG emissions (as CO-equivalents) were reduced by up to 27% with the additions of reed straw and/or zeolite. Our results indicate that reed straw or zeolite can be recommended as amendments to reduce GHG emissions from duck manure; however, superphosphate is more effective in reducing NH emissions.

[Estimation of leaf area index by normalized composite vegetation index fusing the spectral feature of canopy water content]

The accurate inversion of leaf area index (LADI) in canopy is very important for guiding crop management and assessing crop yield. Sixty samples belonging to corn in four different areas of Jilin City were scanned by ASD field pro3 and LAI-2000 for optical data and LAI. A new vegetation index, the normalized composite Vegetation index (NCVI), containing the factor of canopy water content, is proposed in the present paper for a better quantitative estimation of LAI than with the remotely sensed normalized difference vegetation index (NDVI), especially in the arid and semi-arid areas. A model was built for inversion of LAI with NCVI, and experience validation. The results showed that there was a good linear correlation between the simulation LAI inversed from NCVI model and the real LAI values. The model breaking the limitations of the traditional empirical models for LAI inversion has a good result for estimating LAI of the dense canopy whose LAI value was greater than 3. In addition, NCVI model was very sensitive to the water environment of soil, and the inversion result in the arid and semi-arid areas was superior to the general area.

[Analysis and modeling of hyperspectral singularity in rice under Cd pollution]

In order to detect the Cd stress levels of rice growing in natural environment fast and accurately, based on wavelet transform technology in the visible light and near-infrared region (NIR), a method of identifying stress levels of rice under Cd pollution was explored. The hyperspectral data, biochemical parameters and heavy metals concentration in folium were collected for the rice growing in natural farmlands. Wavelet transform of hyperspectral reflectance (350-1 300 nm) was performed by using Daubechies 5 mother function and wavelet energy coefficients of spectral reflectance were extracted. In addition, the model between wavelet energy coefficient and Cd content was established. The result showed that the wavelet coefficients of the fifth decomposition level (d5) proved successful for detecting Cd pollution of rice; the singularity range of rice located in the region around 550-810 nm of spectral signal under Cd pollution; and the singularity amplitude was 0.04; The centre of modulus maxima located at 700 nm. Regression model based on third level wavelet energy coefficient can estimate the Cd content of rice accurately with the coefficient of determination (R2) of 0.958, and root mean square error (RMSE) of 0.122. It can be concluded that the singularity analysis technology applying wavelet transform to reflectance has been shown to be very promising in detecting rice under Cd pollution effectively, and wavelet energy coefficients can estimate Cd content of rice, and provide important reference for detecting other metal-induced stress on crop.

[Multi-diagnosis space models of As stress in rice based on hyperspectral indices]

High arsenic content in rice can influence the chlorophyll, water content and structure in their leaves, reduce the rate of photosynthesis and change their spectral features. Multiple models for diagnosing As contamination in rice based on spectral parameters were studied. Sixty samples belonging to mature rice in three different areas were scanned by ASD field pro3 for optical data. Arsenic reference values were obtained by atomic absorption spectrometry. First, correlation analysis was used between 9 hyperspectral indices and As content in rice, and three indices (PSNDa, fWBI, SIPI) were extracted to diagnose As contamination in rice, which were respectively sensitive to chlorophyll, water content and structure of leaves, then took the three indices to form a diagnosis spectral indices space (PSNDa-fWBI, PSNDa-SIPI, fWBI-SIPI) of As stress in rice. Second, principal component analysis and independent component analysis were also applied in these 9 hyperspectral indices, and two principal components (F1, F2) and two independent components(ICA1, ICA2) were extracted. These four components (F1, F2, ICA1, ICA2) were all correlated with As content in rice, and composed another two diagnosis spaces (F1-F2, ICA1-ICA2) for predicting As contamination. And these spaces composed a multiple diagnosis space model which diagnosed As contamination in rice of test area from different level, and showed a good result.

Seasonal changes in antifreeze protein gene transcription and water content of beetle Microdera punctipennis (Coleoptera, Tenebrionidae) from Gurbantonggut desert in Central Asia

Desert beetle Microdera punctipennis (Coleoptera: Tenebriondae) is a special species in Gurbantonggut Desert in Central Asia. To investigate the possible strategy it employs for cold survival, seasonal changes in supercooling point (SCP), body water content, haemolymph osmolality and antifreeze protein gene (Mpafp) expression were measured over 13 months. Our results show SCPs in M. punctipennis adults changed from -8.0°C in summer to -18.7°C in winter. During winter, adults endured modest water loss; total water decreased from 65.4 percent in summer to 55.9% in winter. Mpafp mRNAs level increased by 13.1 fold from summer to early winter, and haemolymph osmolality increased accordingly from 550 mOsm to 1486 mOsm. Correlation coefficient of Mpafp mRNAs level and SCP indicates that Mpafp mRNA explained 65.3 percent of the variation in SCPs. The correlation between Mpafp mRNA level and total water reflected an indirect influence of antifreeze protein on water content via reducing SCP.

[Research on hyperspectral information parameters of chlorophyll content of rice leaf in Cd-polluted soil environment]

The remote sensing pollution mechanism in Cd-polluted soil is discussed depending on the research into the chlorophyll content of Cd-polluted rice leaf in the present paper. The response models of remote sensing information parameters, which reflected chlorophyll content variety of rice canopy with soil Cd pollution degree, were established based on Hyperion satellite data and a great number of ground experiment data. To extract sensitive remote sensing parameters for Cd pollution, multiple discriminant analysis (MDA) was applied to the reflectivity of 447-925 nm in Hyperion data and five remote sensing information parameters, including MCARI, NPCI, RVSI, NDVI and Depth671. Experiments indicated that MCARI is the most sensitive parameter to the chlorophyll content of Cd-polluted rice, whose response coefficient is 0.59. In the extent of 1.0-2.0 mg x kg(-1) of Cd pollution concentration in soil, MCARI curve shows a small decline. In the extent of 2.0-3.0 mg x kg(-1) of Cd pollution concentration in soil, MCARI curve is horizontal. Above 3.0 mg x kg(-1), MCARI shows a significant drop trend and so on. The research results showed that the chlorophyll content is a good indicator for nutrition situation of plant, capacity of photosynthesis and each developmental stage. And the chlorophyll remote sensing parameters in crop have a great significance for monitoring heavy metal pollution This study will help improve the precision and limitation of statistical methods and provide theoretical basis for and technical approach to monitoring soil Cd pollution in large area using hyperspectral remote sensing technology. However, the precision of pollution model needs to be improved.

The effectiveness of weekly iron supplementation regimen in improving the iron status of Chinese children and pregnant women

It is evident that intermittent iron supplementation is better than daily supplementation in two aspects: iron absorption is more efficient and has insignificant side effects in contrast to the daily dose. The significantly higher daily iron loss observed in the daily iron supplemented groups rats also suggests alterations in total body iron metabolism. Based on serum ferritin distribution patterns, intermittent iron supplementation avoids temporary iron overload with daily iron supplemented. We conclude that weekly iron supplementation scheme is safer and easier to administer. This feasible strategy for the control of iron deficient anemia in pregnant women and children would be an effective iron-supplementation program (Baily et al., 1993).