Advances in Noble Metal-Decorated Metal Oxide Nanomaterials for Chemiresistive Gas Sensors: Overview.

Highly sensitive gas sensors with remarkably low detection limits are attractive for diverse practical application fields including real-time environmental monitoring, exhaled breath diagnosis, and food freshness analysis. Among various chemiresistive sensing materials, noble metal-decorated semiconducting metal oxides (SMOs) have currently aroused extensive attention by virtue of the unique electronic and catalytic properties of noble metals. This review highlights the research progress on the designs and applications of different noble metal-decorated SMOs with diverse nanostructures (e.g., nanoparticles, nanowires, nanorods, nanosheets, nanoflowers, and microspheres) for high-performance gas sensors with higher response, faster response/recovery speed, lower operating temperature, and ultra-low detection limits. The key topics include Pt, Pd, Au, other noble metals (e.g., Ag, Ru, and Rh.), and bimetals-decorated SMOs containing ZnO, SnO2, WO3, other SMOs (e.g., In2O3, Fe2O3, and CuO), and heterostructured SMOs. In addition to conventional devices, the innovative applications like photo-assisted room temperature gas sensors and mechanically flexible smart wearable devices are also discussed. Moreover, the relevant mechanisms for the sensing performance improvement caused by noble metal decoration, including the electronic sensitization effect and the chemical sensitization effect, have also been summarized in detail. Finally, major challenges and future perspectives towards noble metal-decorated SMOs-based chemiresistive gas sensors are proposed.

Heterostructured α-Fe2 O3 @ZnO@ZIF-8 Core-Shell Nanowires for a Highly Selective MEMS-Based ppb-Level H2 S Gas Sensor System.

Highly selective and sensitive H2 S sensors are in high demand in various fields closely related to human life. However, metal oxide semiconductors (MOSs) suffer from poor selectivity and single MOS@metal organic framework (MOF) core-shell nanocomposites are greatly limited due to the intrinsic low sensitivity of MOF shells. To simultaneously improve both selectivity and sensitivity, heterostructured α-Fe2 O3 @ZnO@ZIF-8 core-shell nanowires (NWs) are meticulously synthesized with the assistance of atomic layer deposition. The ZIF-8 shell with regular pores and special surface functional groups is attractive for excellent selectivity and the heterostructured α-Fe2 O3 @ZnO core with an additional electron depletion layer is promising with enhanced sensitivity compared to a single MOS core. As a result, the heterostructured α-Fe2 O3 @ZnO@ZIF-8 core-shell NWs achieve remarkable H2 S sensing performance with a high response (Rair /Rgas  = 32.2 to 10 ppm H2 S), superior selectivity, fast response/recovery speed (18.0/31.8 s), excellent long-term stability (at least over 3 months), and relatively low limit of detection (down to 200 ppb) at low operating temperature of 200 °C, far beyond α-Fe2 O3 @ZIF-8 or α-Fe2 O3 @ZnO core-shell NWs. Furthermore, a micro-electromechanical system-based H2 S gas sensor system with low power consumption is developed, holding great application potential in smart cities.

Recent Progress on Flexible Room-Temperature Gas Sensors Based on Metal Oxide Semiconductor.

With the rapid development of the Internet of Things, there is a great demand for portable gas sensors. Metal oxide semiconductors (MOS) are one of the most traditional and well-studied gas sensing materials and have been widely used to prepare various commercial gas sensors. However, it is limited by high operating temperature. The current research works are directed towards fabricating high-performance flexible room-temperature (FRT) gas sensors, which are effective in simplifying the structure of MOS-based sensors, reducing power consumption, and expanding the application of portable devices. This article presents the recent research progress of MOS-based FRT gas sensors in terms of sensing mechanism, performance, flexibility characteristics, and applications. This review comprehensively summarizes and discusses five types of MOS-based FRT gas sensors, including pristine MOS, noble metal nanoparticles modified MOS, organic polymers modified MOS, carbon-based materials (carbon nanotubes and graphene derivatives) modified MOS, and two-dimensional transition metal dichalcogenides materials modified MOS. The effect of light-illuminated to improve gas sensing performance is further discussed. Furthermore, the applications and future perspectives of FRT gas sensors are also discussed.

Highly sensitive and stable MEMS acetone sensors based on well-designed α-Fe2O3/C mesoporous nanorods.

Highly sensitive and stable acetone gas sensors based on MEMS substrate supported carbon nanoparticles decorated mesoporous α-Fe2O3 (C-d-mFe2O3) nanorods (NRs) derived from Fe-MIL-88B-NH2 NRs were first synthesized via a sequential process including a facile hydrothermal reaction and one-step pyrolysis at a moderate temperature in air. The MEMS architecture ensures low power consumption, small size, and high integration of the sensor. The obtained C-d-mFe2O3 NRs exhibit good thermal stability and superior acetone sensing performance with excellent response (Ra/Rg = 5.2 to 2.5 ppm) and selectivity, fast response/recovery speed (10/27 s), and low detection limit of 500 ppb at 225 °C. Furthermore, the acetone sensor exhibits remarkable long-term stability and repeatability even after being stored in air for over 10 months. The enhanced acetone sensing performance could be attributed to the large specific surface area of mesoporous α-Fe2O3 NRs, highly conductive carbon nanoparticles on the surface, and the formation of α-Fe2O3/C heterojunction. Density functional theory (DFT) calculations help to further confirm the superior acetone sensing performance. The competitive performance makes C-d-mFe2O3 NRs gas sensor a great potential for practical application in environmental harmful acetone gas monitoring.

Investigation of stretchable strain sensor based on CNT/AgNW applied in smart wearable devices.

Stretchable strain sensor, an important paradigm of wearable sensor which can be attached onto clothing or even human skin, is widely used in healthcare, human motion monitoring and human-machine interaction. Pattern-available and facile manufacturing process for strain sensor is pursued all the time. A carbon nanotube (CNT)/silver nanowire (AgNW)-based stretchable strain sensor fabricated by a facile process is reported here. The strain sensor exhibits a considerable Gauge factor of 6.7, long-term durability (>1000 stretching cycles), fast response and recovery (420 ms and 600 ms, respectively), hence the sensor can fulfill the measurement of finger movement. Accordingly, a smart glove comprising a sensor array and a flexible printed circuit board is assembled to detect the bending movement of five fingers simultaneously. Moreover, the glove is wireless and basically fully flexible, it can detect the finger bending of wearer and display the responses distinctly on an APP of a smart phone or a host computer. Our strain senor and smart glove will broaden the materials and applications of wearable sensors.

Determination of the Optimal Cutoff Value of Triglyceride That Corresponds to Fasting Levels in Chinese Subjects With Marked Hypertriglyceridemia.

The level of triglyceride (TG) ≥ 2. 3 mmol/L is suggestive of marked hypertriglyceridemia (HTG) and requires treatment with a triglyceride-lowering agent in high-risk and very high-risk patients as recommended by the 2019 ESC/EAS guidelines for the management of dyslipidemia. However, the optimal cutoff value required to diagnose non-fasting HTG that corresponds to the fasting goal level of 2.3 mmol/L in Chinese subjects is unknown. This study enrolled 602 cardiology inpatients. Blood lipid levels, including calculated non-high-density lipoprotein cholesterol (non-HDL-C) and remnant cholesterol (RC), were measured at 0, 2, and 4 h after a daily Chinese breakfast. Of these, 482 inpatients had TG levels of <2.3 mmol/L (CON group) and 120 inpatients had TG levels of ≥2.3 mmol/L (HTG group). Receiver operating characteristic (ROC) curve analysis was used to determine the cutoff values for postprandial HTG that corresponded to a target fasting level of 2.3 mmol/L. Marked hypertriglyceridemia (≥2.3 mmol/L) was found in 120 (19.9%) patients in this study population. The levels of non-fasting TG and RC increased significantly in both groups and reached the peak at 4 h after a daily meal, especially in the HTG group (p < 0.05). The optimal cutoff value of TG at 4 h, which corresponds to fasting TG of ≥2.3 mmol/L, that can be used to predict HTG, was 2.66 mmol/L. According to the new non-fasting cutoff value, the incidence of non-fasting HTG is close to its fasting level. In summary, this is the first study to determine the non-fasting cutoff value that corresponds to a fasting TG of ≥2.3 mmol/L in Chinese patients. Additionally, 2.66 mmol/l at 4 h after a daily meal could be an appropriate cutoff value that can be used to detect non-fasting marked HTG in Chinese subjects.

High optoelectronic performance of a local-back-gate ReS2/ReSe2 heterojunction phototransistor with hafnium oxide dielectric.

A high optoelectronic performance ReS2/ReSe2 van der Waals (vdW) heterojunction phototransistor utilizing thin hafnium oxide (HfO2) as a local-back-gate dielectric layer was prepared and studied. The heterojunction-based phototransistor exhibits a superior electrical performance with a large rectification ratio of ∼103. Furthermore, unlike diode-like heterojunction devices, the innovative introduction of a local-back-gate in this phototransistor provides an outstanding gate-tunable capability with an ultra-low off-state current of 433 fA and a high on/off current ratio of over 106. And under optical excitation of a wide spectrum from 400 to 633 nm, an excellent photodetection responsivity at the 104 A W-1 level and the maximum normalized detectivity of 1.8 × 1015 Jones @ 633 nm have been demonstrated. Such high performances are attributed to the band alignment of the type-II heterojunction and the suppression of dark current by the local-back-gate. This work provides a promising reference for two-dimensional (2D) Re-based heterojunction optoelectronic devices.

Comparison of the Reductions in LDL-C and Non-HDL-C Induced by the Red Yeast Rice Extract Xuezhikang Between Fasting and Non-fasting States in Patients With Coronary Heart Disease.

Background: Xuezhikang, an extract of red yeast rice, effectively lowers fasting blood lipid levels. However, the influence of Xuezhikang on the non-fasting levels of low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) has not been explored in Chinese patients with coronary heart disease (CHD). Methods: Fifty CHD patients were enrolled and randomly divided into two groups (n = 25 each) to receive 1,200 mg/d of Xuezhikang or a placebo for 6 weeks as routine therapy. Blood lipids were repeatedly measured before and after 6 weeks of treatment at 0, 2, 4, and 6 h after a standard breakfast containing 800 kcal and 50 g of fat. Results: The serum LDL-C levels significantly decreased, from a fasting level of 3.88 mmol/L to non-fasting levels of 2.99, 2.83, and 3.23 mmol/L at 2, 4, and 6 h, respectively, after breakfast (P < 0.05). The serum non-HDL-C level mildly increased from a fasting level of 4.29 mmol/L to non-fasting levels of 4.32, 4.38, and 4.34 mmol/L at 2, 4, and 6 h post-prandially, respectively, and the difference reached statistical significance only at 4 and 6 h after breakfast (P < 0.05). After 6 weeks of Xuezhikang treatment, the patients had significantly lower fasting and non-fasting serum levels of LDL-C and non-HDL-C (P < 0.05) than at pretreatment. The LDL-C levels were reduced by 27.8, 28.1, 26.2, and 25.3% at 0, 2, 4, and 6 h, respectively, and the non-HDL-C levels were reduced by 27.6, 28.7, 29.0, and 28.0% at 0, 2, 4, and 6 h, respectively, after breakfast. No significant difference was found in the percent reductions in the LDL-C and non-HDL-C levels among the four different time-points. Conclusions: Six weeks of Xuezhikang treatment significantly decreased LDL-C and non-HDL-C levels, with similar percent reductions in fasting and non-fasting states in CHD patients, indicating that the percent change in non-fasting LDL-C or non-HDL-C could replace that in the fasting state for evaluation the efficacy of cholesterol control in CHD patients who are unwilling or unable to fast.

Non-HDL-C Is More Stable Than LDL-C in Assessing the Percent Attainment of Non-fasting Lipid for Coronary Heart Disease Patients.

This study aimed to compare the percentage attainment of fasting and non-fasting LDL-C and non-HDL-C target levels in coronary heart disease (CHD) patients receiving short-term statin therapy. This study enrolled 397 inpatients with CHD. Of these, 197 patients took statins for <1 month (m) or did not take any statin before admission (CHD1 group), while 204 patients took statins for ≥1 m before admission (CHD2 group). Blood lipid levels were measured at 0, 2, and 4 h after a daily breakfast. Non-fasting LDL-C and non-HDL-C levels significantly decreased after a daily meal (P < 0.05). Both fasting and non-fasting LDL-C or non-HDL-C levels were significantly lower in the CHD2 group. The percentage attainment of LDL-C <1.4 mmol/L at 2 and 4 h after a daily breakfast was significantly higher than that during fasting (P < 0.05), but the percent attainment of non-fasting non-HDL-C <2.2 mmol/L was close to its fasting value (P > 0.05). Analysis of c-statistic showed that non-fasting cut-off points for LDL-C and non-HDL-C were 1.19 and 2.11 mmol/L, corresponding to their fasting goal levels of 1.4 and 2.2 mmol/L, respectively. When post-prandial LDL-C and non-HDL-C goal attainments were re-evaluated using non-fasting cut-off points, there were no significant differences in percentage attainment between fasting and non-fasting states. Non-HDL-C is more stable than LDL-C in assessing the percent attainment of non-fasting lipid for coronary heart disease patients. If we want to use LDL-C to assess the percent attainment of post-prandial blood lipids, we may need to determine a lower non-fasting cut-off point.

Postprandial triglyceride-rich lipoproteins-induced premature senescence of adipose-derived mesenchymal stem cells via the SIRT1/p53/Ac-p53/p21 axis through oxidative mechanism.

The accumulation of senescent adipose-derived mesenchymal stem cells (AMSCs) in subcutaneous white adipose tissue (WAT) is the main cause for the deterioration of WAT and the subsequent age-related disorders in obesity. The number of AMSCs staining positively for senescence-associated-ß-galactosidase (SA-ß-Gal) increased significantly after incubation with postprandial triglyceride-rich lipoproteins (TRL), accompanied by an impaired cell proliferation capacity and increased expression of inflammatory factors. Besides, the expression of anti-aging protein, silent mating-type information regulation 2 homolog 1 (SIRT1), was downregulated significantly, while those of acetylated p53 (Ac-p53), total p53, and p21 proteins were upregulated significantly during postprandial TRL-induced premature senescence of AMSCs. Furthermore, the production of intracellular reactive oxygen species (ROS) in the TRL group increased significantly, while pretreatment with the ROS scavenger N-acetyl-L-cysteine effectively attenuated the premature senescence of AMSCs by decreasing ROS production and upregulating SIRT1 level. Thus, postprandial TRL induced premature senescence of AMSCs through the SIRT1/p53/Ac-p53/p21 axis, partly through increased oxidative stress.

Precise preparation of WO3@SnO2 core shell nanosheets for efficient NH3 gas sensing.

Development of high-performance ammonia (NH3) sensor is imperative for monitoring NH3 in the living environment. In this work, to obtain a high performance NH3 gas sensor, structurally well-defined WO3@SnO2 core shell nanosheets with a controllable thickness of SnO2 shell layer have been employed as sensing materials. The prepared core shell nanosheets were used to obtain a miniaturized gas sensor based on micro-electro-mechanical system (MEMS). By tuning the thickness of SnO2 layer via atomic layer deposition, a series of WO3@SnO2 core-shell nanosheets with tunable sensing properties were realized. Particularly, the sensor base on the fabricated WO3@SnO2 nanosheets with 20-nm SnO2 shell layer demonstrated superior gas sensing performance with the highest response (1.55) and selectivity toward 15 ppm NH3 at 200 °C. This remarkable enhancement of NH3 sensing ability could be ascribed to the formation of unique WO3-SnO2 core-shell heterojunction structure. The detailed mechanism was elucidated by the heterojunction-depletion model with the help of specific band alignment.

Fabrication of a Micro-Electromechanical System-Based Acetone Gas Sensor Using CeO2 Nanodot-Decorated WO3 Nanowires.

Preparation of reliable, stable, and highly responsive gas-sensing devices for the detection of acetone has been considered to be a key issue for the development of accurate disease diagnosis systems via exhaled breath. In this paper, novel CeO2 nanodot-decorated WO3 nanowires are successfully synthesized through a sequential hydrothermal and thermolysis process. Such CeO2 nanodot-decorated WO3 nanowires exhibited a remarkable enhancement in acetone-sensing performance based on a miniaturized micro-electromechanical system device, which affords high response (S = 1.30-500 ppb, 1.62-2.5 ppm), low detection limit (500 ppb), and superior selectivity toward acetone. The improved performance of the acetone sensor is likely to be originated from the fast carrier transportation of WO3 nanowires, the formation of WO3-CeO2 heterojunctions, and the existence of large amounts of oxygen vacancies in CeO2. The improved reaction thermodynamics and sensing mechanisms have also been revealed by the specific band alignment and X-ray photoelectron spectroscopy analysis.

A computerized resolution visual acuity test in preschool and school age children.

AIM: To develop a novel approach called the Autoacuity Tester, and to evaluate its validity, especially the sensitivity and specificity for detecting amblyopia. METHODS: Children aged from 3 to 12y (n=552) were enrolled in the study. The validity of the Autoacuity Tester was evaluated by comparing it to the Tumbling E Early Treatment Diabetic Retinopathy Study (ETDRS) acuity chart for school age children, and Lea Symbols and Teller acuity card (TAC) for preschool children. The repeatability was assessed by coefficient of repeatability (COR). The sensitivity and specificity for detecting amblyopia were calculated. RESULTS: The mean difference (95% limits of agreement) between the Autoacuity Tester and the ETDRS tests were -0.03 (-0.24, 0.19) logMAR for the school age group. In preschool children, the mean difference was 0.04 (-0.14, 0.21) logMAR between the Autoacuity Tester and the TAC and 0.00 (-0.17, 0.18) logMAR between the Autoacuity Tester and the Lea Symbols. For the school age group, the COR was 0.20 logMAR for the Autoacuity Tester and 0.18 logMAR for the ETDRS. For the preschool group, the COR was 0.13 logMAR for the Autoacuity Tester and 0.21 logMAR for TAC. The Autoacuity Tester (88%) is more sensitive than TAC (72%) in detecting amblyopia (P=0.04), while had similar specificity (92% vs 90%, P=0.20). CONCLUSION: The Autoacuity Tester provides a reliable alternative for assessing visual acuity, and offers advantage of higher testability and repeatability for preschool children.

Hierarchical highly ordered SnO2 nanobowl branched ZnO nanowires for ultrasensitive and selective hydrogen sulfide gas sensing.

Highly sensitive and selective hydrogen sulfide (H2S) sensors based on hierarchical highly ordered SnO2 nanobowl branched ZnO nanowires (NWs) were synthesized via a sequential process combining hard template processing, atomic-layer deposition, and hydrothermal processing. The hierarchical sensing materials were prepared in situ on microelectromechanical systems, which are expected to achieve high-performance gas sensors with superior sensitivity, long-term stability and repeatability, as well as low power consumption. Specifically, the hierarchical nanobowl SnO2@ZnO NW sensor displayed a high sensitivity of 6.24, a fast response and recovery speed (i.e., 14 s and 39 s, respectively), and an excellent selectivity when detecting 1 ppm H2S at 250 °C, whose rate of resistance change (i.e., 5.24) is 2.6 times higher than that of the pristine SnO2 nanobowl sensor. The improved sensing performance could be attributed to the increased specific surface area, the formation of heterojunctions and homojunctions, as well as the additional reaction between ZnO and H2S, which were confirmed by electrochemical characterization and band alignment analysis. Moreover, the well-structured hierarchical sensors maintained stable performance after a month, suggesting excellent stability and repeatability. In summary, such well-designed hierarchical highly ordered nanobowl SnO2@ZnO NW gas sensors demonstrate favorable potential for enhanced sensitive and selective H2S detection with long-term stability and repeatability.

Comparison of remnant cholesterol levels estimated by calculated and measured LDL-C levels in Chinese patients with coronary heart disease.

BACKGROUND: Evidence about whether remnant cholesterol (RC), especially non-fasting RC, is a causal risk factor for coronary heart disease (CHD) in Chinese subjects is rare. Recently, estimated RC level (RCe) was applied in many studies with large population. We aimed to compare fasting and non-fasting RCe calculated by LDL-C level determined by different methods in Chinese subjects, and investigate their contributions to CHD. METHODS: Levels of TC, TG and HDL-C were measured directly in 273 CHD patients (CHD group) and 136 controls (CON group) before and at 4 h after a daily breakfast. LDL-C level was measured directly or calculated by Friedewald equation at TG < 4.5 mmol/L. RC level estimated by calculated or measured LDL-C was termed as RCe1 or RCe2. Contributions of different RC levels to CHD were evaluated by multivariable logistic regression analysis. RESULTS: Both RCe1 and RCe2 increased significantly at 4 h after breakfast (both p < 0.05). RCe1 was significantly higher than RCe2 in fasting or non-fasting state (p < 0.05). RCe1 was closely related to RCe2, especially in the highest quartile of RCe1 (p < 0.05). Non-fasting RCe1 or RCe2 and fasting RCe2 independently predicted CHD after adjustment for traditional risk factors (all p < 0.05). CONCLUSIONS: Although RCe1 was significantly higher than RCe2, non-fasting RCe, no matter RCe1 or RCe2, after a daily breakfast was an independent predictor for CHD risk in Chinese subjects, indicating that the non-fasting state is critical in the development of atherosclerosis.

Systematic Study of the SiOx Film with Different Stoichiometry by Plasma-Enhanced Atomic Layer Deposition and Its Application in SiOx/SiO2 Super-Lattice.

Atomic scale control of the thickness of thin film makes atomic layer deposition highly advantageous in the preparation of high quality super-lattices. However, precisely controlling the film chemical stoichiometry is very challenging. In this study, we deposited SiOx film with different stoichiometry by plasma enhanced atomic layer deposition. After reviewing various deposition parameters like temperature, precursor pulse time, and gas flow, the silicon dioxides of stoichiometric (SiO2) and non-stoichiometric (SiO1.8 and SiO1.6) were successfully fabricated. X-ray photo-electron spectroscopy was first employed to analyze the element content and chemical bonding energy of these films. Then the morphology, structure, composition, and optical characteristics of SiOx film were systematically studied through atomic force microscope, transmission electron microscopy, X-ray reflection, and spectroscopic ellipsometry. The experimental results indicate that both the mass density and refractive index of SiO1.8 and SiO1.6 are less than SiO2 film. The energy band-gap is approved by spectroscopic ellipsometry data and X-ray photo-electron spectroscopy O 1s analysis. The results demonstrate that the energy band-gap decreases as the oxygen concentration decreases in SiOx film. After we obtained the Si-rich silicon oxide film deposition, the SiO1.6/SiO2 super-lattices was fabricated and its photoluminescence (PL) property was characterized by PL spectra. The weak PL intensity gives us greater awareness that more research is needed in order to decrease the x of SiOx film to a larger extent through further optimizing plasma-enhanced atomic layer deposition processes, and hence improve the photoluminescence properties of SiOx/SiO2 super-lattices.

Epigenetic regulation of alternative splicing.

Alternative splicing (AS) serves as an additional regulatory process for gene expression after transcription, and it generates distinct mRNA species, and even noncoding RNAs (ncRNAs), from one primary transcript. Generally, AS can be coupled with transcription and subjected to epigenetic regulation, such as DNA methylation and histone modifications. In addition, ncRNAs, especially long noncoding RNAs (lncRNAs), can be generated from AS and function as splicing factors ("interactors" or "hijackers") in AS. Recently, RNA modifications, such as the RNA N6-methyladenosine (m6A) modification, have been found to regulate AS. In this review, we summarize recent achievements related to the epigenetic regulation of AS.

Differentiation between mycoplasma and viral community-acquired pneumonia in children with lobe or multi foci infiltration: a retrospective case study.

OBJECTIVES: To analyse the clinical features, inflammatory markers and radiographs of community-acquired pneumonia (CAP) cases with lobe or multi foci infiltration; with a special focus on factors which allow the differential diagnosis of viral and mycoplasma pneumonia. SETTING: Retrospective chart review of CAP cases in a large university teaching hospital. PARTICIPANTS: 126 paediatric CAP cases, with lobe or multi foci infiltration, presenting between May 2012 and April 2013. Demographic data, clinical presentation on admission or referral, laboratory tests, prior history, and radiography were collected for each case if available. PRIMARY AND SECONDARY OUTCOME MEASURES: We used univariate and multivariate logistic regression to determine the significant factors which allow the differential diagnosis of viral and mycoplasma CAP with lobe or multi foci infiltration. RESULTS: There were 71 (56%) male and 55 (44%) female CAP cases with lobar or multi foci infiltration. 70 pneumonia cases were caused by Mycoplasma pneumoniae and 18 by viruses. Univariate analysis of the mycoplasma and viral causes of the CAP revealed that increased respiratory rate, wheeze, male gender and lymphocyte percentage were the factors associated with the differentiation of mycoplasma and viral aetiologies of pneumonia (p<0.05). A stepwise logistic regression analysis was performed to assess independent factors which allow the differential diagnosis of viral and mycoplasma pneumonia. Increased respiratory rate, wheeze, and lymphocyte percentage were reliable independent factors which allow the differential diagnosis of viral and mycoplasma CAP with lobar or multi foci infiltration. CONCLUSIONS: Whether the CAP with lobar or multi foci infiltration was caused by mycoplasma species or viruses could not be inferred from the radiological patterns. Wheeze, lymphocyte percentage and respiratory rate were independent factors which allowed the differential diagnosis of viral and mycoplasma CAP with lobar or multi foci infiltration.

[Role of Dlx1 natural antisense transcript in mice brain development].

OBJECTIVE: To explore the role of Dlx1as, a natural antisense transcript, in mice brain development. METHODS: Based on the bioinformatic and molecular biological findings, we confirmed whether the Dlx1as has a poly-A tail. The temporal expressions of Dlx1as and Dlx1 mRNA were determined by quantitative real-time PCR and the spatial expressions of Dlx1as and Dlx1 mRNA were compared by using in situ hybridization. RESULTS: Dlx1as had a poly-A signal. Dlx1as's expression was at a high level through a period of time in the embryo development, which was similar with Dlx1 mRNA in temporal but different in spatial. CONCLUSIONS: Dlx1as is highly expressed in a certain period during mice brain development, which spatially supplements the mRNA expression of D1x1. Therefore, it is supposed that Dlx1as influences the mice brain development by regulating Dlx1 mRNA.

[Mechanism of arsenic trioxide-induced apoptosis in hepatic blastoma cells HepG2].

OBJECTIVE: To investigate the mechanism of arsenic trioxide (As(2)O(3)) induced apoptosis in hepatic blastoma cells HepG2 and its effects on cell nuclear matrix related protein promyelocytic leukaemia (PML). METHODS: HepG2 cells were cultured in MEM medium and treated with different concentrations of As(2)O(3) for either 24 h or 96 h. In situ terminal deoxynucleotidyl transferase (TdT) labeling (TUNEL) and DNA ladder were applied to detect apoptosis. Confocal microscopy and western blot were performed to observe the expression of PML. RESULTS: TUNEL positive apoptotic cells and DNA ladder could be detected in As(2)O(3) treated groups. The expression of PML decreased in HepG2 cells with 2 micro mol/L As(2)O(3), and micropunctates characteristic of PML protein in HepG2 cell nuclei almost disappeared after the treatment of 5 micro mol/L As(2)O(3). CONCLUSION: As(2)O(3) induces HepG2 tumor cell apoptosis in a time- and concentration-dependent manner. As(2)O(3) may degradate the PML protein in HepG2 cell nuclei. The decreased expression of PML is closely correlated with apoptosis. Nuclear matrix associated protein PML could be the target of As(2)O(3) therapy.