[Genetic screening in early diagnosis of neonatal WAS gene-related disorders]

Objective: To explore the clinical value of genetic screening for early identification of WAS gene-related disorders in newborns. Methods: This was a retrospective study. Neonatal Genome Project from Children's Hospital of Fudan University collected 5 800 high-risk newborns in the neonatal intensive care unit to study the patients' genetic causes using high-throughput sequencing from January 2016 to December 2017. Eleven newborns (all were boys) with pathogenic or likely pathogenic variants in WAS gene were enrolled. Data of clinical characteristics,gene variants and genotype-phenotype correlation were collected and summarized. Results: Eleven patients included 5 cases with Wiskott-Aldrich syndrome (WAS) and 6 cases with X-linked thrombocytopenia (XLT).Two patients with WAS developed clinical manifestations in the early neonatal period,and 3 patients in 5-8 weeks after birth. Three neonates with XLT were hospitalized for other diseases in the first place.Their platelet count was found to be reduced after admission to hospital, and diagnosis was made after genetic testing. Eleven pathogenic or likely pathogenic variants in WAS gene were identified. Among them, 7 were first reported in this study, including 2 frame shift variants c.138delG and c.388_390del, 4 splicing variants c.1453+1G>A,c.734+1G>C,c.135G>A and c.1453+3G>C, and 1 missense variant c.1118C>T. The other 4 reported variants were c.777+1G>A,c.107_108delTT, c.436delC and c.1509_*3delAGTG. Conclusions: The clinical features of WAS gene-related disorders in neonatal period lack specificity. Genetic screening in newborns plays an important role in the early diagnosis of diseases and provides providing evidence for the early intervention.

A sensitive electrochemical aptasensor for Mucin 1 detection based on catalytic hairpin assembly coupled with PtPdNPs peroxidase-like activity

In this work, an ultrasensitive aptasensor for the detection of Mucin 1 (MUC1) was presented based on the target-induced catalytic hairpin assembly combined with excellent mimic peroxidase performance of PtPd bimetallic nanoparticles (PtPdNPs). Traditionally, the cyclic reuse of target protein was achieved by protein conversion with enzyme cleavage or polymerization, which is costly and complex. However, in this work, it can be performed by simple strand displacement. In addition, PtPdNPs, a mimic peroxidase, was used a probe to catalyze the oxidation of tetramethylbenzidine (TMB) by H₂O₂, leading to the electrochemical signal amplification. With this ingenious design, the prepared aptasensor for MUC1 detection showed a favorable linear response from 100 fg mL^-1 to 1 ng mL^-1 and a relatively low detection limit of 16 fg mL^-1. The proposed biosensor possessed acceptable stability, selectivity and reproducibility for MUC1 assay. Additionally, the fabricated aptasensor has been successfully applied to detect MUC1 in serum samples with satisfactory results. This new strategy supplied one efficient approach to improve signal amplification, which also open an avenue for sensitivity enhancement in targets detection.

Aptamer based electrochemical assay for protein kinase activity by coupling hybridization chain reaction

The present work reported a simple, lable-free and sensitive electrochemical method for the detection of protein kinase A (PKA) activity. This method was based on the specific recognition of aptamer and the aptamer-induced hybridization chain reaction (HCR) amplification strategy. The aptasensor was constructed by immobilizing capture probe on a gold electrode via an Au-S bond. When adenosine triphosphate (ATP) aptamer was introduced, its one terminus hybridized with capture probe and the other hybridized with the complementary region of an auxiliary probe, which other region triggered HCR between two hairpin DNA (H1 and H2) to form a long DNA concatamer. At last a large number of electroactive methyle blue (MB) molecules were assembled on the dsDNA concatamer, which generated a significantly amplified electrochemical signal. In the presence of ATP, the HCR would not be performed because the aptamer specifically bond to ATP and the electrochemical response would decrease. However, when ATP and PKA coexisted, the electrochemical response would recovery because that ATP had been translated into ADP by PKA. So the activity of PKA could be effectively monitored according to the change of electrochemical signal. Based on the HCR amplification strategy, the aptasensor showed a wide linear range (4 - 4 ×10⁵ U L^-1) and a low detection limit (1.5 U L^-1) for the detection of PKA. Furthermore, the method was applied to study the inhibitory effect of H-89 on PKA activity. The developed aptasensor was also used to the analysis of drug-induced PKA activity in cell lysates, indicating the potential application of the developed method in the fields of clinical diagnostics and discovery of new targeted drugs.

[Role of maternal drug use and environmental exposure during pregnancy and delivery pattern in allergic infants and toddlers]

Objective: To understand correlation between maternal drug use and environmental exposure during pregnancy and delivery pattern and allergy in infants and toddlers, and provide theoretical bases for the early prevention and intervention of infantile allergies. Methods: Case control study based on cross-sectional investigation was conducted. Thirty-three cities were selected in China. Randomly cluster sampling method was used to select a community in each city as the study sample, the women with infants aged 0-24 months were interviewed in the form of face-to-face questionnaire survey. Infants and toddlers were divided into two groups: case group, including 2 113 children who had allergic symptoms and were diagnosed with allergic disease, and control group, including 6 303 children who never had symptoms of allergic disease. Results: Children whose parents had allergic disease histories were more likely to have allergic disease (OR=3.950) compared with the children whose mother or father had allergic disease histories (OR=2.277). Maternal use of antibiotics (OR=1.396), disinfector exposure (OR=1.386), smoking exposure (OR=1.301) during pregnancy and cesarean delivery (OR=1.255) were risk factors for allergic disease in infants and toddlers, the differences were significant (P<0.05). Conclusion: It is essential to conduct primary prevention of infant allergy during pregnancy, and it is necessary to avoid unnecessary cesarean delivery and irrational antibiotic use, disinfector and smoking exposures during pregnancy.

[Percentile curves on growth among breastfed 1-4 year olds in 8 urban areas]

Objective: To construct the growth percentile curves of weight-, length/height-, head circumference and BMI for 1 to 4 year-olds who had been breastfed in urban areas. Methods: Data was from the longitudinal study on 1 025 breastfed children aged 1 to 4 years, in 8 urban areas during 2008-2012. MLwiN2.25 was selected to construct the multi-level models of weight-for-age,length for-age, head circumference-for-age and BMI-for-age. The models included many growth relevant factors including gender, age, family and social demographic characteristics, perinatal factors, parent biological characteristics, dietary patterns and diseases of childen. Based on these models, predicted values (P(3), P(15), P(50), P(85), P(97)) were estimated to fit the percentiles reference curves. Results: The percentiles reference curves of weight-, length/height, head circumferenceand BMI-for-age for the 1-4 year-olds who had been breastfed in the urban areas were developed. Differences of all the indicators between boys and girls were statistically significant (P<0.001). Weight, length/height, head circumference and BMI were higher in boys than those in girls, with an average differences as 0.56-0.76 kg, 0.89-1.12 cm, 0.64-0.91 cm and 0.31-0.52 kg/m(2). Conclusion: The percentiles reference curves on growth, constructed by the longitudinal observational data and scientific method, were important in reflecting the development of breastfed children in urban areas.

Osteoblast differentiation of rabbit adipose-derived stem cells by polyethylenimine-mediated BMP-2 gene transfection in vitro

The aim of this study was to examine the efficiency of polyethylenimine-mediated transfection of the human bone morphogenetic protein-2 (BMP-2) gene into rabbit adipose-derived stem cells (ADSCs), and its effect on osteoblast differentiation. Adipose tissue was isolated from the necks of adult Japanese white rabbits and cultured in vitro to obtain ADSCs. Gene delivery of BMP-2 was mediated by polyethylenimine and stable transformants were selected by G-418. The expression of BMP-2 mRNA was confirmed by reverse transcription-polymerase chain reaction, and of the BMP-2 protein by ELISA. Osteocalcin and collagen type I were detected by western blot and by an alkaline phosphatase kit. Alizarin red S stain was also utilized to examine osteogenesis. The non-transfected group was considered as a control. In this study, we successfully derived ADSCs from rabbit adipose tissue. Through passages 3-6, the expression of CD29 and CD44 gradually increased, whereas the expression of CD34 and CD45 gradually decreased. Both mRNA and protein expression of BMP-2 were confirmed following polyethylenimine-mediated BMP-2 gene delivery. In addition, the expression of alkaline phosphatase, osteocalcin, and collagen type I was found to be upregulated and alizarin red S staining was positive in transfected ADSCs, indicating BMP-2-induced osteogenesis. Therefore, this study determined that polyethylenimine was able to mediate BMP-2 gene delivery and induce osteogenic differentiation of ADSCs.

Electrodeposition of PtNPs on the LBL assembled multilayer films of (PDDA-GS/PEDOT:PSS)n and their electrocatalytic activity toward methanol oxidation

In the present work, PDDA-functionalized graphene sheets (PDDA-GS) were prepared by reduction with hydrazine hydrate in situ in the presence of poly(diallyldimethylammonium chloride) (PDDA).

[Safety and efficacy of Cox-maze Ⅲ procedure for patients with atrial fibrillation associated with rheumatic mitral valve disease]

OBJECTIVE

To evaluate the safety and efficacy of cut-and-sew Cox-Maze (CM) Ⅲ procedure for patients with atrial fibrillation associated with rheumatic mitral valve disease.

METHODS

Patients received mitral valve replacement and CM procedure between January 2007 and July 2015, were 1∶1 matched and assigned to CM Ⅳ group (undergoing surgical ablation) and CM Ⅲ group (undergoing cut-and-sew CM Ⅲ). Safety indices, mortality rate, complications and recovery rate of sinus rhythm were compared between the two groups.

RESULTS

Mean extracorporeal circulation time was (154±22) min in the CM Ⅲ group and (136±21) min in the CM Ⅳ group (P<0.001), and aortic clamp time was (85±9) min in the CM Ⅲ group and (74±12) min in the CM Ⅳ group (P<0.001). One patient (1.18%) in the CM Ⅲ group died of multi-organ failure 4 day after left ventricular rupture being sucessfully repaired, and 2 patients died (2.35%) in the CM Ⅳ group ( 1 due to left ventricular rupture and 1 due to low cardiac output syndrome). There was no significant difference in mortality between the two groups. Temporary pacemaker were applied for 76 cases (89.41%) in the CM Ⅲ and 70 cases (82.35%) in the CM Ⅳ group, without a statistical difference (P=0.186). There were also no statistical difference between the two groups in intraoperative urinary volume, postoperative drainage of fluid volume, hemoglobinuria, ventilator time, ICU time, hospital stay and the incidence of the complications (all P>0.05). Sinus rhythm recovery rate was 62.35 % in the CM Ⅲ group and 57.65 % in the CM Ⅳ group, without a statistical difference (P=0.531) at the operation day, but at discharge a statistical difference was found (97.62% in the CM Ⅲ group vs 81.93% in the CM Ⅳ group, P<0.001). All patients were followed up for three months, and no deaths occurred. Sinus rhythm recovery rate was 96.43 % in the CM Ⅲ group and 86.75% in the CM Ⅳ group, with a statistical difference (P=0.024).

CONCLUSION

The cut-and-sew Cox-Maze Ⅲ procedure is a safe and effective method for patients with atrial fibrillation associated with rheumatic mitral valve disease.

[The effect and safety of tirofiban on acute ST segment elevation myocardial infarction patients receiving no early reperfusion therapy]

OBJECTIVE

To study the efficacy and safety of tirofiban on acute ST segment elevation myocardial infarction (STEMI) in patients who do not receive early reperfusion therapy.

METHODS

A total of 153 STEMI patients without early reperfusion therapy were randomly distributed into tirofiban group (therapeutic group, n=78) and non-tirofiban group (control group, n=75). Coronary angiography was performed on the 5(th) and 10(th) day after treatment, and percutaneous coronary intervention (PCI) was conducted when necessary. The differences of initial patency of the infarct related artery (IRA), bleeding complication and clinic events within 30 days between these two groups were compared.

RESULTS

Tirofiban did not increase the percentage of patients with initial patency of IRA (60.3% vs 64.0%, P=0.63). The percentage of patients with thrombolysis in myocardial infarction (TIMI) 3 after PCI was 100.0% in tirofiban group and 97.1% in the control group (P=0.09). However, application of tirofiban significantly decreased poor myocardial perfusion rate after PCI (1.4% vs 8.8%, P=0.04). No significant differences were observed in major adverse cardiovascular events (MACE) (3.8% vs 2.7%, P=0.68) between therapeutic and control group. The same is true for mild (5/78 vs 4/75 cases, P=0.78) and severe hemorrhage (2/78 vs 1/75 cases, P=0.58), and severe thrombocytopenia (2/78 vs 0/75 cases, P=0.10) between these two groups within 30 days.

CONCLUSIONS

Tirofiban did not increase initial patency in STEMI patients without early reperfusion therapy. However, it can improve myocardial perfusion after PCI.

KCNE1 112G>a polymorphism and atrial fibrillation risk: a meta-analysis

KCNE1, a membrane protein that spans the membrane once is responsible for modulating potassium channel functions and plays an important role in the etiology of arrhythmia. Emerging evidence indicates that a common polymorphism (112G>A; rs1805127 G>A) in the KCNE1 gene contributes to atrial fibrillation (AF) risk; however, these studies showed inconclusive results. In this meta-analysis, we derived a more precise estimation of the association between the KCNE1 112G>A polymorphism and AF risk. The following databases were searched: Web of Science (1945-2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966-2013), EMBASE (1980-2013), CINAHL (1982-2013), and the Chinese Biomedical Database (1982-2013). The crude odds ratios with their 95% confidence intervals were calculated. Nine case-control studies were included, with a total of 1792 AF patients and 1924 healthy controls. The meta-analysis results indicated that the KCNE1 112G variant is associated with an increased risk of AF. Further subgroup analysis based on ethnicity revealed significant associations between the KCNE1 112G variant and an increased risk of AF among both Asians and Caucasians. No publication bias was detected in this meta-analysis. In conclusion, our results indicate that the KCNE1 112G polymorphism may be a risk factor for AF. KCNE1 112G>A may be useful as a biomarker for predicting the development of AF.

Assessment of heavy metals/metalloid (As, Pb, Cd, Ni, Zn, Cr, Cu, Mn) concentrations in edible fish species tissue in the Pearl River Delta (PRD), China

The major aim of this study was to investigate heavy metal content of edible fish in the PRD. Eleven species of fish (consisting of 711 individuals) [catfish (Clarias fuscus), tilapia (Oreochromis mossambicus), grass carp (Ctenopharyngodon idellus), bighead carp (Aristichthys nobilis), mandarin fish (Siniperca kneri), snakehead (Channa asiatiea), black bass (Micropterus salmoides), mangrove snapper (Lutjanus griseus), star snapper (Lutjanu stellatus), snubnose pompano (Trachinotus blochii) and orange-spotted grouper (Epinephelus coioides)] were collected for the analyses of heavy metals. Overall concentrations (mg/kg, ww) in the fish muscles were: As (0.03-1.53), Pb (0.03-8.62), Cd (0.02-0.06), Ni (0.44-9.75), Zn (15.7-29.5), Cr (0.22-0.65), Cu (0.79-2.26), Mn (0.82-6.91). Significant level of Pb were found in tilapia at all locations. It is recommended that heavy metal concentrations in different fish species must be determined on a regular basis in the future so as to reduce human health risks from acute and chronic food intoxication.

Heat transfer coefficient of cryotop during freezing

Cryotop is an efficient vitrification method for cryopreservation of oocytes. It has been widely used owing to its simple operation and high freezing rate. Recently, the heat transfer performance of cryotop was studied by numerical simulation in several studies. However, the range of heat transfer coefficient in the simulation is uncertain. In this study, the heat transfer coefficient for cryotop during freezing process was analyzed. The cooling rates of 40 percent ethylene glycol (EG) droplet in cryotop during freezing were measured by ultra-fast measurement system and calculated by numerical simulation at different value of heat transfer coefficient. Compared with the results obtained by two methods, the range of the heat transfer coefficient necessary for the numerical simulation of cryotop was determined, which is between 9000 W/(m(2)·K) and 10000 W/(m (2)·K).

Agents that induce pseudo-allergic reaction

Pseudo-allergic reactions may result from the activation of inflammatory or anaphylactic mechanisms independent of antigen-specific immune responses. Recent statistics show that pseudo-allergic reactions may represent as high as two thirds of all immediate hypersensitivity reactions, implying a great amount of morbidity and numerous health care costs. In this review, we concentrate on agents mediating pseudo-allergic reactions and evaluate accurately the available information on their modes of action. The agents discussed here are divided into three types: (i) Direct mast cell activators, which may activate mast cells in an IgE-independent manner, such as opioid drugs, basic secretagogues and calcium ionophore A23187; (ii) Complement activators, including liposomes, radiocontrast media and Cremophor EL, which may activate the complement system by different pathways: the classical pathway, the mannose-binding lectin pathway or the alternative pathway; (iii) Nonsteroidal anti-inflammatory drugs, which may inhibit the function of cyclooxygenase-1, resulting in the occurrence of adverse reactions. In addition, nonclinical detection methods of pseudo-allergic reactions are also reviewed in order to supply valuable information for clinical diagnosis.

Simultaneous detection of multiple-gas species by correlation spectroscopy using a multimode diode laser

Simultaneous detection of multiple-gas species has for the first time (to our knowledge) been demonstrated by using a multimode diode-laser-based correlation spectroscopy (MDL-COSPEC) scheme. Concentration measurements of a mixture of CO(2) and CO gas were performed by probing overlapping line spectra around 1.57microm using an MDL. Species identification and corresponding quantitive analysis were implemented by correlating the recorded absorption signals of the sample gas mixtures with those of the reference gases of particular interest, attaining accuracies of 2% and 1%, respectively. MDL-COSPEC is a generic technique with potential application for simultaneous detection of multiple gases having resolvable narrow lines.

Hypotensive response in rats and toxicological mechanisms induced by shuanghuanglian, an herbal extract mixture

Shuanghuanglian (SHL), an extract mixture isolated from three medicinal herbs, has been used in China as an injection in traditional Chinese medicine to treat viral or bacterial infection. This study examined the hypotensive response in rats induced by SHL and its possible mechanisms. Mean arterial pressure (MAP) and electrocardiograms (ECGs) were studied after intravenous injection of histamine and SHL. Diphenhydramine, an H1 receptor antagonist, the compound 48/80, a promoter of histamine release, and cromolyn, a histamine release inhibitor, were also used to investigate the potential mechanisms of that response. In addition, the histamine level in plasma was measured after administration of SHL and compound 48/80. Both SHL and histamine led to a MAP reduction immediately but did not affect ECGs when initially administered in a similar manner, though this reduction was partially attenuated by diphenhydramine. Pretreatment blocked the rats' reaction to compound 48/80 but not to SHL. The plasma histamine level in rats was also elevated by SHL. SHL can induce severe hypotension through histamine release upon initial administration. In combination with the direct effects of its histaminelike substances on target tissue, SHL likely has the potential to cause an anaphylactoid reaction.