Metabolic habitat imaging with hemodynamic heterogeneity predicts individual progression-free survival in high-grade glioma

AIM

We design a feasibility study to obtain a set of metabolic-hemodynamic habitats for tackling tumor spatial metabolic patterns with hemodynamic information.

MATERIALS AND METHODS

Preoperative data from 69 high-grade gliomas (HGG) patients with subsequent histologic confirmation of HGG were prospectively collected (January 2016 to March 2020) after concurrent chemoradiotherapy (CCRT). Four vascular habitats were automatically segmented by multiparametric magnetic resonance imaging (MRI). The metabolic information, either at enhancing or edema tumor regions, was obtained by two neuroradiologists. The relative habitat volumes were used for weight estimation procedures for computing the coefficients of a linear regression model using weighted least squares (WLS) for metabolite semiquantifications (i.e. the Cho/NAA ratio and the Cho/Cr ratio) at vascular habitats. Multivariate Cox proportional hazard regression analyses are used to obtain the odds ratio (OR) and develop a nomogram using weighted estimators corresponding to each covariate derived from Cox regression coefficients.

RESULTS

There was a strongly correlation between perfusion indexes and the Cho/Cr ratio (rCBV, r=0.71) or Cho/NAA ratio (rCBV, r=0.66) at high-angiogenic enhancing tumor habitats (HAT) habitat. Compared isocitrate dehydrogenase (IDH) mutation to their wild type, the IDH wild type had significantly decreased Cho/Cr ratio (IDH mutation: Cho/Cr ratio = 2.44 ± 0.33, IDH wildtype: Cho/Cr ratio = 2.66 ± 0.36, p=0.02) and Cho/NAA ratio (IDH mutation: Cho/Cr ratio = 4.59 ± 0.61, IDH wildtype: Cho/Cr ratio = 4.99 ± 0.66, p=0.022) at the HAT. The C-index for the median progression-free survival (PFS) prediction was 0.769 for the Cho/NAA nomogram and 0.747 for the Cho/Cr nomogram through 1000 bootstrapping validation.

CONCLUSIONS

Our findings suggest that spatial metabolism combined with hemodynamic heterogeneity is associated with individual PFS to HGG patients post-CCRT.

V-O Species-Doped Carbon Frameworks Loaded with Ru Nanoparticles as Highly Efficient and CO-Tolerant Catalysts for Alkaline Hydrogen Oxidation

Efficient and CO-tolerant catalysts for alkaline hydrogen oxidation (HOR) are vital to the commercial application of anion exchange membrane fuel cells (AEMFCs). Herein, a robust Ru-based catalyst (Ru/VOC) with ultrasmall Ru nanoparticles supported on carbon frameworks with atomically dispersed V-O species is prepared elaborately. The catalyst exhibits a remarkable mass activity of 3.44 mA μgPGM, which is 31.3 times that of Ru/C and even 4.7 times higher than that of Pt/C. Moreover, the Ru/VOC anode can achieve a peak power density (PPD) of 1.194 W cm-2, much superior to that of Ru/C anode and even better than that of Pt/C anode. In addition, the catalyst also exhibits superior stability and exceptional CO tolerance. Experimental results and density functional theory (DFT) calculations demonstrate that V-O species are ideal OH- adsorption sites, which allow Ru to release more sites for hydrogen adsorption. Furthermore, the electron transfer from Ru nanoparticles to the carbon substrate regulates the electronic structure of Ru, reducing the hydrogen binding energy (HBE) and the CO adsorption energy on Ru, thus boosting the alkaline HOR performance and CO tolerance of the catalyst. This is the first report that oxophilic single atoms distributed on carbon frameworks serve as OH- adsorption sites for efficient hydrogen oxidation, opening up new guidance for the elaborate design of high-activity catalysts for the alkaline HOR.

Octahedral/Tetrahedral Vacancies in Fe3 O4 as K-Storage Sites: A Case of Anti-Spinel Structure Material Serving as High-Performance Anodes for PIBs

Potassium-ion batteries (PIBs) have attracted more and more attention as viable alternatives to lithium-ion batteries (LIBs) due to the deficiency and uneven distribution of lithium resources. However, it is shown that potassium storage in some compounds through reaction or intercalation mechanisms cannot effectively improve the capacity and stability of anodes for PIBs. The unique anti-spinel structure of magnetite (Fe3 O4 ) is densely packed with thirty-two O atoms to form a face-centered cubic (fcc) unit cell with tetrahedral/octahedral vacancies in the O-closed packing structure, which can serve as K+ storage sites according to the density functional theory (DFT) calculation results. In this work, carbon-coated Fe3 O4 @C nanoparticles are prepared as high-performance anodes for PIBs, which exhibit high reversible capacity (638 mAh g-1 at 0.05 A g-1 ) and hyper stable cycling performance at ultrahigh current density (150 mAh g-1 after 9000 cycles at 10 A g-1 ). In situ XRD, ex-situ Fe K-edge XAFS, and DFT calculations confirm the storage of K+ in tetrahedral/octahedral vacancies.

[Performance of pulmonary function test in people aged 40 years and above in China, 2019-2020]

Objective: To understand the performance of pulmonary function tests in people aged ≥40 years and its changes in China, and provide evidence for the evaluation of the effect of chronic obstructive pulmonary disease (COPD) prevention and control in China. Methods: The subjects of the survey were from COPD surveillance during 2014-2015 and during 2019-2020, which covered 31 provinces (autonomous regions and municipalities) in China. The survey used multi-stage stratified cluster random sampling method, the trained investigators conducted face-to-face interview to know whether subjects had previous pulmonary function testing or not. Complex sampling weighting was used to estimate the rate of pulmonary function testing in people aged ≥40 years, and the pulmonary function testing rates of the two COPD surveillance periods were compared. Results: A total of 148 427 persons were included in the analysis, including 74 591 persons during 2014-2015 and 73 836 persons during 2019-2020. In 2019-2020, the pulmonary function testing rate in Chinese residents aged ≥40 years was 6.7% (95%CI: 5.2%-8.2%), the rate in men (8.1%, 95%CI: 6.7%-9.6%) was higher than that in women (5.4%, 95%CI: 3.7%- 7.0%), and the rate in urban residents (8.3%, 95%CI: 6.1%-10.5%) was higher than that in rural residents (4.4%, 95%CI: 3.8%-5.1%). The rate of pulmonary function testing increased with the increase of education level. During 2019-2020, the residents with history of chronic respiratory diseases had the highest rate of pulmonary function testing (21.2%, 95%CI: 16.8%-25.7%), followed by the residents with respiratory symptoms (15.1%, 95%CI: 11.8%-18.4%) , the pulmonary function testing rate in those who knew the name of chronic respiratory disease was higher than that in those who did not knew the name of respiratory disease, and the pulmonary function testing rate in former smokers was higher than that in current smokers and non-smokers. Those exposed to occupational dust and/or harmful gases had a higher rate of pulmonary function testing compared with those who were not exposed, and those who used polluted fuels indoors had a lower rate of pulmonary function testing than those who did not use polluted fuels indoors (all P<0.05). Compared with 2014-2015, the pulmonary function testing rate in residents aged ≥40 years in China increased by 1.9 percentage points during 2019-2020, and the rate of pulmonary function testing in groups with different characteristics all increased, and the rates of pulmonary function testing increased by 7.4 percentage points and 7.1 percentage points in residents with respiratory symptoms and in those with history of chronic respiratory diseases (all P<0.05). Conclusions: Compared with 2014-2015, the rate of pulmonary function testing increased in China during 2019-2020 and the increase in residents with history of chronic respiratory diseases and respiratory symptoms was relatively obvious, but the overall pulmonary function testing rate was still at a low level. Effective measures should be taken to further increase the rate of pulmonary function testing.

[The perforator flap of ipsilateral nasolabial sulcus used to repair the defect after the eradication of nasal vestibular squamous cell carcinoma]

Objective: To investigate the feasibility of only surgical resection for nasal vestibular squamous cell carcinoma and the efficacy of perforator flap of ipsilateral nasolabial sulcus in repairing postoperative defects. Methods: The clinical data of 8 cases with squamous cell carcinoma of the nasal vestibule who admitted to Department of Facial Plastic and Reconstructive Surgery, Eye & ENT Hospital, Fudan University were analyzed, including 6 males and 2 females, aged from 38 to 75 years. The tumor of the nasal vestibule was eradicated in time after making definite diagnosis of lesions, then the perforators flap of the ipsilateral nasolabial sulcus was used for repairment, without performing further chemotherapy or radiotherapy after surgery. The tumor recurrence, facial appearance, nostril form, donor area scar, nasal ventilation function, and cutaneous sensation were evaluated after surgery. Descriptive analysis was used in this research. Results: There were 2 cases of stage T1 and 6 cases of stage T2 in 8 cases. After 32 to 45 months of following-up, no recurrence accurred and all the flaps survived well. However, there was about 2 mm necrosis of the transplanted flap in the lateral foot of the alar in one case, which was healed well by carrying out wound care after 10 d. And the dark color flap was occurred in another case, showing the flap's backflow trouble, yet it was improved with addressing timely during 5 d postoperation. Pincusion-like deformity of the transplanted flap occurred in 4 cases (50%), which subsided gradually after 6 months. The morphology of the anterior nostril was altered in 4 cases (50%), but there was no ventilation trouble and no need for addressment in any case. The postoperative facial appearance was rated as excellentor good with hidden scar in the donor site, and the sensation of the transplanted flaps was indistinct from the surrounding tissue after 3 months. Conclusions: Surgical resection of nasal vestibular squamous cell carcinoma with tumor stage T1-2 is a feasible treatment. And it is the one of the best reconstructive methods of the perforator flap of the ipsilateral nasolabial sulcus to repair the deformities after the surgery.

Tuning the p-Orbital Electron Structure of s-Block Metal Ca Enables a High-Performance Electrocatalyst for Oxygen Reduction

Most previous efforts are devoted to developing transition metals as electrocatalysts guided by the d-band center model. The metals of the s-block of the periodic table have so far received little attention in the application of oxygen reduction reactions (ORR). Herein, a carbon catalyst with calcium (Ca) single atom coordinated with N and O is reported, which displays exceptional ORR activities in both acidic condition (E_1/2  = 0.77 V, 0.1 m HClO₄ ) and alkaline condition (E_1/2  = 0.90 V, 0.1 m KOH). The CaN, O/C exhibits remarkable performance in zinc-air battery with a maximum power density of 218 mW cm^-2 , superior to a series of catalysts reported so far. X-ray absorption near-edge structure (XANES) characterization confirms the formation of N- and O-atom-coordinated Ca in the carbon matrix. Density functional theory (DFT) calculations reveal that the high catalytic activity of main-group Ca is ascribed to the fact that its p-orbital electron structure is regulated by N and O coordination so that the highest peak (E_P ) of the projected density of states (PDOS) for the Ca atom is moved close to the Fermi level, thereby facilitating the adsorption of ORR intermediates and electron transfer.

One-Step Construction of V5S8 Nanoparticles Embedded in Amorphous Carbon Nanorods for High-Capacity and Long-Life Potassium Ion Half/Full Batteries

Potassium ion batteries (KIBs) have attracted great attention recently as a promising large-scale energy storage system by virtue of the bountiful K resource and low standard hydrogen potential of K⁺/K. However, their development is hindered by the limited capacity and inferior cycling stability resulting from the large size of K⁺. Here, a unique vanadium sulfide@carbon nanorod is designed and synthesized for high-performance KIBs. Thanks to the hybrid structure, abundant active sites, fast ion diffusion, and capacitive-like electrochemical behavior of the electrode, the anode exhibits a large specific capacity (468 mA h g^-1 after 100 cycles at 0.1 A g^-1), predominant rate performance (205 mA h g^-1 at 5 A g^-1), and impressive cycling stability (171 mA h g^-1 for 4000 cycles at 3 A g^-1). Furthermore, the constructed KIB full cell demonstrates 229 mA h g^-1 at 0.5 A g^-1 and 86% capacity retention over 300 cycles.

Cage-Confinement Pyrolysis Strategy to Synthesize Hollow Carbon Nanocage-Coated Copper Phosphide for Stable and High-Capacity Potassium-Ion Storage

Metal phosphides with a high theoretical capacity and low redox potential have been proposed as promising anodes for potassium-ion batteries (PIBs). A reasonable configuration design and introduction of a hollow structure with adequate internal void spaces are effective strategies to overcome the volume expansion of metal phosphides in potassium-ion batteries. Herein, we report a cage-confinement pyrolysis strategy to obtain hollow nanocage-structured nitrogen/phosphorus dual-doped carbon-coated copper phosphide (Cu3P/CuP2@NPC), which exhibits a high initial charge capacity (409 mA h g-1 at 100 mA g-1) and an outstanding cycle performance (100 mA h g-1 after 5000 cycles at 1000 mA g-1) as an anode material for PIBs. The novel hollow nanocage structure could prevent volume expansion during cycling and reduce the electron/ion diffusion distance. Besides, the nitrogen/phosphorus dual-doped carbon-coated layer could promote electronic conductivity. In situ X-ray diffraction (XRD) measurements are conducted to study the potassiation/depotassiation mechanism of Cu3P/CuP2@NPC and reveal the structure stability during the cycle process, which further proves that the design ideas of the conductive carbon layer and the hollow structure with adequate internal void spaces are successful.

Boosting Hydrazine Oxidation Reaction on CoP/Co Mott-Schottky Electrocatalyst through Engineering Active Sites

The hydrazine oxidation reaction (HzOR), as a substitute for the sluggish oxygen evolution reaction (OER), is identified as a promising powerfrugal strategy for hydrogen production through water splitting. However, the HzOR activity of the present electrocatalysts is unsatisfying because the work potential is much higher than the theoretical value. Herein, we design a typical Mott-Schottky electrocatalyst consisting of CoP/Co nanoparticles for the HzOR, which exhibits remarkable HzOR activity with ultralow potentials of -69 and 177 mV at 10 and 100 mA cm^-2, respectively. It stands out in a range of cobalt-based materials and is even comparable to some precious-metal-based materials composed of Pt or Ru. A shown by with structural characterization and density functional theory (DFT) calculations, the interfaces between CoP/Co nanoparticles not only provide the active sites of HzOR but also promote the multistep dehydrogenation reaction of N₂H₄, thus enhancing the HzOR activity.

Energetic Metal-Organic Frameworks Derived Highly Nitrogen-Doped Porous Carbon for Superior Potassium Storage

The carbonaceous materials with low cost and high safety have been considered as promising anodes for potassium-ion batteries (PIBs). However, it is still a challenge to design a carbonaceous material with long cycle life and high rate performance due to the poor K⁺ reaction kinetics. Herein, this article reports a N-doped porous carbon framework (NPCF) with a high nitrogen content of 13.57 at% within high doping level of the pyrrolic N and pyridinic N, which exhibits a high reversible capacity of 327 mA h g^-1 over 100 cycles at a current density of 100 mA g^-1 , excellent rate capability (144 and 105 mA h g^-1 at 10 and 20 A g^-1 , respectively) and great cyclability of 258.9 mA h g^-1 after 2000 cycles at 1 A g^-1 . Such a high rate performance and excellent cycling stability anode material is seldom reported in PIBs. Density functional theory (DFT) calculations reveal that the pyrrolic and pyridinic N-doping are helpful to enhance the K adsorption ability, thereby increasing the specific capacity.

Nutrition, Immigration and Health Determinants Are Linked to Verbal Fluency among Anglophone Adults in the Canadian Longitudinal Study on Aging (CLSA)

OBJECTIVES

Later-life cognitive impairment is an important health issue; however, little is known about the condition among diverse groups such as immigrants. This study aims to examine whether the healthy immigrant effect exists for verbal fluency, an indicator of cognitive functioning, among anglophone middle-aged and older adults in Canada.

METHODS

Using from the baseline data of the Canadian Longitudinal Study on Aging (CLSA), multiple linear regression was employed to compare associations among immigrants (recent and long-term) and Canadian-born residents without dementia for two verbal fluency tests, the Controlled Oral Word Association Test (COWAT) and the Animal Fluency (AF) task. Covariates included socioeconomic, physical health, and dietary intake.

RESULTS

Of 8,574 anglophone participants (85.7% Canada-born, 74.8% aged 45-65 years, 81.8% married, 81.9% with a post-secondary degree), long-term immigrants (settled in Canada >20 years) performed significantly better than Canadian-born residents for the COWAT (42.8 vs 40.9) but not the AF task (22.4 vs 22.4). Results of the multivariable adjusted regression analyses showed that long-term immigrants performed better than Canadian-born peers in both the COWAT (B=1.57, 95% CI: 0.80-2.34) and the AF test (B=0.57, 95% CI: 0.19-0.95), but this advantage was not observed among recent immigrants. Other factors associated with low verbal fluency performance included being single, socioeconomically disadvantaged, having hypertension, excess body fat, and consuming low amounts of pulses/nuts or fruit/vegetables.

CONCLUSIONS

Long-term immigrants had higher verbal fluency test scores than their Canadian-born counterparts. Immigration status, social, health and nutritional factors are important considerations for possible intervention and prevention strategies for cognitive impairment.

The functional difference of eight chitinase genes between male and female of the cotton mealybug, Phenacoccus solenopsis

The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) is a polyphagous insect that attacks tens of plant and causes substantial economic loss. Insect chitinases are required to remove the old cuticle to allow for continued growth and development. Though insect chitinases have been well studied in tens of insects, their functions in mealybug are still not addressed. Here, we sequenced the transcriptomes of adult males and females, from which eight chitinase genes were identified. We then used the method of rapid amplification of cDNA ends to amplify their full length. Phylogenetic analysis indicated that these genes clustered into five subgroups. Among which, group II PsCht2 had the longest transcript and was highly expressed at second instar nymph. PsCht10, PsCht3-3 and PsIDGF were highly expressed in the adult females, whereas PsCht4 and PsCht4-1 were significantly expressed at the male pupa and adult male. Next, we knocked down all eight chitinase genes by feeding the double-stranded RNA. Knockdown of PsCht4 or PsCht4-1 led to the failure of moult and, silencing PsCht5 resulted in pupation defect, while silencing PsCht10 led to small body size, suggesting these genes have essential roles in development and can be used as a potential target for pest control.

[Epidemiological investigation and analysis of allergic rhinitis among 6-12 years old children in Zaoyang City of Hubei Province]

Objective:The aim of this study is to investigate the epidemiological characteristics of allergic rhinitis(AR) among 6-12 years old children in Zaoyang.Method:All the children aged from 6 to 12 years old from 2 primary schools in Zaoyang in June 2018 were randomly selected as the research objects.The AR questionnaire was designed, and the epidemiological investigation was carried out. The results were analyzed by SPSS 20.0 software.Result:The prevalence rate of children aged 6-12 in Zaoyang was 13.7%,the prevalence rate of girls was 11.9%,and the prevalence rate of boys was 15.3%. The prevalence rate of boys was higher than that of girls,but the difference was not statistically significant(χ²=3.033,P>0.05).Univariate analysis showed that the factors related to AR were age(t=2.729,P<0.01), family history of allergic diseases (χ²=172.067,P<0.01),exposure to smoking or dust environment (χ²=43.091,P<0.01),exposure to smoking environment during pregnancy (χ²=6.09,P<0.05) and pet feeding history (χ²=9.473,P<0.01).Conclusion:The incidence of allergic rhinitis among 6-12 years old children in Zaoyang is high,age,family history of allergic diseasese,exposure to smoking or dust environment,exposure to smoking environment during pregnancy,and pet feeding history are risk factors for the incidence of allergic rhinitis in children.

[An analysis of relative factors, bacteriological profile and antibiogram of neonatal sepsis]

Objective: This study was designed to identify the relative factors, bacteriological profile and their antibiotic susceptibility pattern of neonatal sepsis. Methods: A retrospective survey was conducted on the clinical information, pathogen identification and antibiotic sensitivity results of 425 newborns with neonatal sepsis admitted to Nanjing Maternity and Child Health Care Hospital from 2010 to 2017. Of the 425 positive blood-cultures, 148 (34.82%) were early-onset neonatal sepsis (EOS) and 277 (65.18%) were late-onset neonatal sepsis (LOS). Clinical information and pathogen identification were compared between EOS and LOS. Antibiotic sensitivity of gram negative organisms (G(-)) and gram positive organisms (G(+)) were also detected. Results: The rates of premature delivery (78.70%, n=218), low birth weights (67.15%, n=186) and cesarean delivery (59.57%, n=165) were significantly increased in LOS (P<0.05) compared with those rates in EOS, which were 41.89% (n=62), 37.84% (n=56) and 46.62% (n=69). Parturients fever (18.24%, n=27) and meconium like amniotic fluid (25.68%, n=38) were significantly increased in EOS (P<0.05) compared with those rates in LOS, which were 7.94% (n=22) and 5.42% (n=15). Among the identified pathogen, the incidence of G(-) and G(+) bacteria were 216 (50.83%) and 201 (47.29%) respectively, and the rest was Candida glabrata (1.88%, n=8). Escherichia coli 68 (16.00%) was the predominant isolate followed by Klebsiella pneumoniae (13.18%, n=56). The detection rate of Hemolytic staphylococcus (10.81%, n=16) was significantly increased in EOS (P<0.001) compared with LOS (1.44%, n=4). However, the incidence of Klebsiella pneumonia (5.88%, n=44) was higher in LOS (P=0.024) compared with EOS (8.11%, n=12). Most of the gram positive isolates exhibited high resistance to penicillin (90.32%-100.00%) and cephalosporin group antibiotics (25.00%-100.00%). Similarly, the majority of the gram negative isolates showed higher resistance to ampicillin (83.33%-100.00%), but susceptible to aminoglycosides (0-11.76%), quinolones (0-17.65%) and β-lactams (0-5.88%). Conclusion: Among the study population, the percent of preterm, low birth weight and cesarean section were higher in LOS while parturients fever and meconium-like amniotic fluid were higher in EOS. The pathogens with the highest detection rate were Escherichia coli and Klebsiella pneumoniae. The results of antibiotic susceptibility test showed that common pathogens had high resistance to commonly used antibacterial drugs.

[Value of base excess in predicting the prognosis of patients with paraquat poisoning]

Objective: To explore prognostic factors of acute paraquat poisoning (APP) , analyze the correlation between base excess (BE) and plasma concentration of paraquat (C-PQ) and discuss BE level in evalua-tion of prognosis of acute paraquat poisoning patients. Methods: We retrospectively selected 84 APP patients who admitted to Emergency Intensive Care Unit (EICU) of our hospital from 2009.9.1 to 2015.8.31.Clinical data from 84 APP patients were analyzed. BE、C-PQ、time of gastric lavagesince ingestion、time of hemoperfusion since ingestion、severity index of paraquat poisoning (SIPP) 、white blood cell (WBC) 、percentage of neutrophils (N%) 、hemoglobin (HB) 、creatinine (Cr) 、alanine aminotransferase (ALT) 、aspartate aminotransferase (AST) 、partial pressure of oxygen (PaO(2)) 、partial pressure of carbon dioxide (PaCO(2)) and other laboratory parameters were measured. A total of 41 patients in non-survivors died during the 30 days after admission and 43 patients in survivors survived during the 30 days. The factors of prognosis in paraquat poisoining and the role of BE in evalu-ating prognosis was analyzed, as well as the correlation between BE and C-PQ. Results: 1.Logistic regression analyses showed BE、C-PQ、ALT、AST、Cr was of prognostic significance[odds ratio (OR) of BE: 0.511, 95%CI 0.267, 0.978; C-PQ:-=0.999, 95%CI 0.999, 1.000; both P<0.05] ; 2.The area under the receiver operating characteristic curve (ROC curve) of BE、C-PQ and prognosis were 0.775、0.927 respectively, BE≤-1.7 mmol/L was the best cut-off value, the sensitivity、specificity for predicting were 82.9%、62.8%, the evaluation value was lower to C-PQ>3 273.935 ng/ml (AUC 0.927, 78.0%、95.3%) ; 3.BE negative correlated with C-PQ[-1.100 (-4.100, -0.200) , -5.900(-8.650, -2.500) , both P<0.05]. (r=-0.4, P<0.01). Conclusion: These results suggest that BE may be useful for the prediction of prognosis in PQ poisoning and BE negative correlated with C-PQ.

A multiple-threshold AR(1) model

We consider the model Zt = φ (0, k)+ φ(1, k)Zt–1 + at (k) whenever rk−1<Zt−1≦rk, 1≦k≦l, with r0 = –∞ and rl =∞. Here {φ (i, k); i = 0, 1; 1≦k≦l} is a sequence of real constants, not necessarily equal, and, for 1≦k≦l, {at(k), t≧1} is a sequence of i.i.d. random variables with mean 0 and with {at(k), t≧1} independent of {at(j), t≧1} for j ≠ k. Necessary and sufficient conditions on the constants {φ (i, k)} are given for the stationarity of the process. Least squares estimators of the model parameters are derived and, under mild regularity conditions, are shown to be strongly consistent and asymptotically normal.

Some comments on spectral representations of non-stationary stochastic processes

The first part of the paper gives a multitude of essentially different representations of a stationary stochastic process. The second part gives a sufficient condition for the sum of two oscillatory processes to be again oscillatory.

Determination of the order of a Markov chain by Akaike's information criterion

Using Akaike's information criterion, we have presented an objective procedure for the determination of the order of an ergodic Markov chain with a finite number of states. The procedure exploits the asymptotic properties of the maximum likelihood ratio statistics and Kullback and Leibler's mean information for the discrimination between two distributions. Numerical illustrations are given, using data from Bartlett (1966), Good and Gover (1967) and some weather records.

MUC13 protects colorectal cancer cells from death by activating the NF-κB pathway and is a potential therapeutic target

MUC13 is a transmembrane mucin glycoprotein that is over produced by many cancers, although its functions are not fully understood. Nuclear factor-κB (NF-κB) is a key transcription factor promoting cancer cell survival, but therapeutically targeting this pathway has proved difficult because NF-κB has pleiotropic functions. Here, we report that MUC13 prevents colorectal cancer cell death by promoting two distinct pathways of NF-kB activation, consequently upregulating BCL-X_L. MUC13 promoted tumor necrosis factor (TNF)-induced NF-κB activation by interacting with TNFR1 and the E3 ligase, cIAP1, to increase ubiquitination of RIPK1. MUC13 also promoted genotoxin-induced NF-κB activation by increasing phosphorylation of ATM and SUMOylation of NF-κB essential modulator. Moreover, elevated expression of cytoplasmic MUC13 and NF-κB correlated with colorectal cancer progression and metastases. Our demonstration that MUC13 enhances NF-κB signaling in response to both TNF and DNA-damaging agents provides a new molecular target for specific inhibition of NF-κB activation. As proof of principle, silencing MUC13 sensitized colorectal cancer cells to killing by cytotoxic drugs and inflammatory signals and abolished chemotherapy-induced enrichment of CD133⁺ CD44⁺ cancer stem cells, slowed xenograft growth in mice, and synergized with 5-fluourouracil to induce tumor regression. Therefore, these data indicate that combining chemotherapy and MUC13 antagonism could improve the treatment of metastatic cancers.

A note on one-dimensional chaotic maps under time reversal

We have furnished further examples on the connection between some standard one-dimensional chaotic deterministic models and stochastic time series models via time reversal.

On the use of the deterministic Lyapunov function for the ergodicity of stochastic difference equations

We have shown that within the setting of a difference equation it is possible to link ergodicity with stability via the physical notion of energy in the form of a Lyapunov function.

Prenatal diagnosis of trisomy 21, 18 and 13 by quantitative pyrosequencing of segmental duplications

Chromosomal aberration mostly occurs in chromosomes 21, 18 and 13, with an incidence approximately 1 out of 160 live births in humans, therefore making prenatal diagnosis necessary in clinics. Current methods have drawbacks such as time consuming, high cost, complicated operations and low sensitivity. In this paper, a novel method for rapid and accurate prenatal diagnosis of aneuploidy is proposed based on pyrosequencing, which quantitatively detects the peak height ratio (PHR) of different bases of segmental duplication. A direct polymerase chain reaction (PCR) approach was undertaken, where a small volume of amniotic fluid was used as the starting material without DNA extraction. Single-stranded DNA was prepared from PCR products and subsequently analyzed using pyrosequencing. The PHR between target and reference chromosome of 2.2 for euploid and 3:2 for a trisomy fetus were used as reference. The reference intervals and z scores were calculated for discrimination of aneuploidy. A total of 132 samples were collected, within trisomy 21 (n = 11), trisomy 18 (n = 3), trisomy 13 (n = 2), and unaffected controls (n = 116). A set of six segmental duplications were chosen for analysis. This method had consistent results with karyotyping analysis, a correct diagnosis with 100% sensitivity and 99.9% specificity.

Fluorescence lifetime imaging of optically levitated aerosol: a technique to quantitatively map the viscosity of suspended aerosol particles

A technique to measure the viscosity of stably levitated single micron-sized aerosol particles.

Association of serum homocysteine levels with the severity and calcification of coronary atherosclerotic plaques detected by coronary CT angiography

AIM

In this study, we aim to evaluate the association of risk factors including homocysteine (Hcy) with the severity and burden of coronary atherosclerotic plaques detected by computed tomography angiography (CTA).

METHODS

Six hundred fifty-nine subjects who underwent CTA for the assessment of coronary artery disease (CAD) were studied. All the subjects enrolled had no clinical cardiovascular disease symptoms. Logistic regression showed apart from age, hypertension, smoking, triglyceride, low-density lipoprotein (LDL) cholesterol, and total bilirubin, Hcy was an independently risk factor of the severity of coronary disease. And Hcy was also found an independent predictor for the presence of calcified plaque. When the participants were divided into 4 groups according to serum Hcy quartiles (Q1-Q4 groups), both the percentage of patients with >50% stenosis and the percentage of patients with calcified plaque were higher in Q4 compared to other groups. The OR of Hcy (>15 µmol/L) for >50% stenosis was 2.212 (95% CI=1.119 to 4.375, P=0.022) and the OR for Hcy (>15 µmol/L) for calcification was 1.668 (95% CI=1.030 to 2.699, P=0.037) respectively.

CONCLUSION

Our study shows Hcy is independently associated with both the severity and calcified plaque detected by CTA. Hcy may provide additional information about CAD in the subjects without clinical symptoms.

Proton pump inhibitors are associated with hypersensitivity reactions to drugs in hospitalized patients: a nested case-control in a retrospective cohort study

BACKGROUND

Previous research has shown that gastric acid suppression by antacid drugs can promote allergic reactions to acid-labile food proteins. No data are available about whether antacid drugs can promote drug hypersensitivity reactions. The most potent and longer lasting inhibition of gastric secretion is provided by proton pump inhibitors (PPIs). We hypothesized that gastric acid suppression by proton pump inhibitors could be causative of drug hypersensitivity reactions during hospitalization.

OBJECTIVE

To estimate the risk of developing drug hypersensitivity reactions during the hospitalization of patients treated with proton pump inhibitors, and other associated factors.

METHODS

A nested case-control in a retrospective cohort study of hospitalized patients from September 2008 to December 2010 (70 771 admissions) was conducted using the registry of cases of interconsultations to the Allergy Department (161 confirmed cases of drug hypersensitivity reactions). A total of 318 controls were matched by first drug suspected in the hypersensitivity reaction, time of admission, age, gender and hospitalization wards.

RESULTS

The relative risk of drug hypersensitivity reaction occurrence during hospitalization of patients treated with PPIs compared with those not treated in the period of study was significant (RR: 3.97; 95% CI: 1.97-8.29). After controlling for confounders in the nested case-control cohort, the use of PPIs persists as a predisposing factor (OR: 4.35; 95% CI: 2-9.45). Personal history of drug allergy and a long hospitalization time were other predisposing factors of drug hypersensitivity reactions (DHRs). The hazard that a DHR has occurred during PPI treatment was 3.7% per day. The hazard for immediate or accelerated reactions was 1.706 (P = 0.003) times that of delayed reactions.

CONCLUSION AND CLINICAL RELEVANCE

In hospitalized patients, the use of proton pump inhibitors was associated with a significant increase risk of drug hypersensitivity reactions along with a personal history of drug allergies and long hospitalization time.

Construction of a recombinant plasmid harbouring the glyceraldenyde-3-phosphate dehydrogenase gene of periodic Brugia malayi and observation on DNA immunity

PURPOSE

Controlling and eliminating lymphatic filariasis will require further research of preventative measures and implementation. Parasite is dependent on glycolysis for ATP production. The glycolytic enzyme glyceraldenyde-3-phosphate dehydrogenase (GAPDH) plays an important role in glycolysis and therefore is either a potential target for anti-parasite drug development or a vaccine candidate. Therefore, we tried to investigate the DNA vaccine-elicited immune responses in BALB/c mice.

MATERIALS AND METHODS

We cloned a gene encoding the glyceraldehyde-3-phosphate dehydrogenase (GAPDH) from periodic Brugia malayi into vector pcDNA3.1. Mice were injected at a dosage of 100 μg recombinant plasmid DNA with CpG intramuscular injection and immunized three times at 2-week intervals. pcDNA3.1 and normal saline were used as control. The tissue of muscles at the 4 weeks after the third injection was collected and target genes were detected using RT-PCR. The humoral responses elicited in mice by inoculation with the recombinant plasmid pcDNA3.1-BmGAPDH were detected using a standard ELISA. Two weeks after the third immunization, stimulation index (SI) was measured using the MTT method and the level of secreted IL-4 and INF-g were detected using ELISA.

RESULTS

Specific gene fragment coding GAPDH was amplified and the recombinant plasmid pcDNA3.1-BmGAPDH was constructed. Post-challenge sera from the mice immunized with the DNA vaccine had specific antibody titres of 1:1600 to 1:6400, and the highest titre was observed in the mice that were inoculated by pcDNA3.1-BmGAPDH/CpG at 6 weeks. At 4 weeks after immunization, the spleens of the mice were obviously enlarged. The proliferation of spleen T lymphocytes seen on the MTT assay was higher in the pcDNA3.1-BmGAPDH group than in the control group (P value <0.05). The levels of IL-4 and INF-γ in serums from the immunized mice were significantly higher than that of the control (P value <0.05).

CONCLUSIONS

We conclude that the recombinant eukaryotic plasmid pcDNA3.1-BmGAPDH could elicit humoral and cellular immune responses in mice.

Effects of hydrogen peroxide on human dentin structure

It has been hypothesized that hydrogen peroxide (H(2)O(2)) bleaching may cause destruction of dentin by a mechanism of protein oxidation. However, to our knowledge, there has been no direct chemical evidence to validate this viewpoint. To investigate the effects of H(2)O(2) on the structure of human dentin, we used Fourier transform infrared spectroscopy (FTIR) and attenuated total reflection (ATR) spectroscopy. Human intact dentin specimens were treated either with 30% H(2)O(2) or Hanks' balanced salt solution (HBSS). Significant differences were observed in ATR spectra parameters. Additionally, demineralized dentin specimens were also tested. They were completely dissolved in the H(2)O(2), but remained intact in the 0.1 N HCl and HBSS. The results suggested that H(2)O(2) attacked both the organic and mineral components of dentin. Destruction of the organic components was mainly because of the oxidizing ability of H(2)O(2), while changes in the mineral components were probably due to its acidity.