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Analysis of Down syndrome failed to be diagnosed after prenatal screening: A multicenter study.
To analyze the characters of Down syndrome (DS) who failed to be diagnosed after prenatal screening and hope to be able to improve the programs of prenatal screening and reduce the missed diagnosis of DS. In this multicenter study, we collected the missed cases from 3 prenatal diagnosis centers and analyzed their characters. A total of 126 DS babies failed to be diagnosed after prenatal screening. Their mothers accepted the prenatal screening in second trimester. We collected the mothers' blood and detected the levels of alpha-fetoprotein (AFP) and the free beta subunit of human chorionic gonadotropin (fβhCG) by time-resolved fluoroimmunoassay. The values were also presented as multiples of the median (MoM) and determined the risk of carrying a fetus with DS by Wallace LifeCycle Elipse analysis software. Compared with normal control group, the level of fβhCG and hCG MoM were dramatically increased, while AFP and AFP MoM were decreased. The area under the receiver-operating-characteristic curve of trisomy 21 was 0.8387 for hCG-MoM and AFP-MoM testing. The sensitivity, specificity, positive predictive value, and negative predictive value were 84.6%, 74.8%, 75.4%, and 83.6%, respectively. Meanwhile, the prediction mode was "0.39957 + 1.90897HCG-MOM -3.32713AFP-MOM". It was worthwhile noting that the risk of 65.9% DS missed diagnosis group were higher than 1/1000, 92.9% higher than 1/3000. However, 72.5% cases in normal control group were lower than 1/3000. Only 9.2% mothers would be higher than the value of risk in 1/1000. The prediction mode of hCG MoM and AFP MoM might be able to help us reduce the missed diagnosis. It is also necessary to adjust more reasonable range of noninvasive prenatal testing with further clinical researches
Comparative Analysis of In situ Fibronectin Using ToF-SIMS, SPI-MS, and dropDESI-MS in a Microfluidic Reactor
Fibronectin is an important biomolecule due to its role in cell differentiation, growth, kinesis, and adhesion. Such biological responses are mediated through membrane recognition and signaling; where fibronectin is found. Studying the outer molecular surface of fibronectin allows deeper insight into the microbiological reactions that occur during these processes. In situ mass spectrometry analysis in aqueous solution accurately represents fibronectin’s chemical components, made possible by a vacuum compatible microfluidic reactor, SALVI (System for Analysis at the Liquid Vacuum Interface). SALVI was paired with the analytical tools: time-of-flight secondary ion mass spectrometer (ToF-SIMS), single photon ionization mass spectrometer (SPI-MS) and drop desorption electrospray ionization mass spectrometer (dropDESI-MS). ToF-SIMS employed a bismuth liquid metal ion beam. Positive and negative ion spectral plots were constructed and analyzed. The advanced light source (ALS) SPI-MS), using a synchrotron vacuum ultraviolet (VUV) light, elicited data depending on varying photoionization efficiencies (PIE). PIE plots were examined for the initial detection of photons of a mass to charge ratio (m/z), resulting in the determination of the ionization efficiency (IE) of a corresponding compound. Both ToF-SIMS and SPI-MS are surface tools, with ion beam impact no further than the second monolayer. DropDESI-MS, analyzed under ambient conditions, utilized a capillary connecting the electrode spray to the mass spectrometer. Charged microdroplets were used to introduce samples to the mass analyzer. Central masses (m/z) from all three apparatuses were identified to their most possible compounds or constituents, demonstrating complementary results. Mass identifications were based on literature survey and results from peer reviewed articles. Our results suggest the need for further research of organic compounds, like fibronectin, to understand their surface compositions in aqueous solution
Enhancing the Chemical Mixture Methodology: Incorporating 20 Health Code Numbers
The Chemical Mixture Methodology (CMM) is used by the Department of Energy (DOE), its contractors, and other private and public organizations for emergency response planning. CMM assesses the potential health impacts on individuals that would result from exposure to an airborne mixture of hazardous chemicals. Health Code Numbers (HCNs) are assigned to each chemical based on the human organs targeted by exposure. In the current CMM, only the top 10 HCNs ranked by severity are included in each CMM analysis. This project focuses on assessing what happens when doubling the potential number of HCNs for each chemical that could be used in each CMM analysis. A total of 361 chemicals were used in our testing (the entire CMM database contains over 3000 chemicals). A set of 127 representative mixtures were prepared for our analysis. Three different concentration distributions (called “ideal”, “realistic”, and “same”) were used for each test mixture, providing us with a total of 381 test cases. CMM results were compared for all 381 test cases using both the 10-HCN approach and the 20-HCN approach. Only a slight difference was observed between the 10- and 20-HCN approaches. This slight difference suggests that the top 10-HCNs give good representation of the potential toxic health effects. This also indicates that it is impractical to incorporate the 20-HCN approach in a future version of the CMM. Therefore, effort should be directed to other aspects of the CMM development such as refining the nervous system effects or respiratory irritant effects in the near future
Based On Body Communication Wireless Medical Monitoring System Construction
Abstractthe concept of the body communication is put forward, the rapid development of portable medical equipment, medical monitoring systems are improving. Through analyzing the characteristics of body communication and the restrictions of medical equipment, we proposed the idea of medical monitoring system of wireless, and elaborated the system's principle of work. The construction of this system to further promote the development of medical monitoring system and provide security for the healthy development of body society
Phenol Adsorption on Nitrogen-Enriched Activated Carbon from Wood Fiberboard Waste
Nitrogen-enriched activated carbons were prepared from wood fiberboard waste using 50% potassium hydroxide solution. Activated carbons were obtained with an impregnation ratio (gram chemical agent/gram wood fiberboard waste) of 3 in 850°C activation temperature carbonized for 60 min. Nitrogen content in activated carbon was 1.33% by analysis. Effects of contact time, pH, adsorbent dosage level, and temperature on phenol adsorption capacity of activated carbons were investigated. Adsorption equilibrium was achieved within 100 min at the given phenol concentration of 250 mg/L. When 0.1 g of the carbon absorbent and 100 mL of phenol solution at 250 mg/L were used, maximum adsorption capacity of phenol on activated carbon can reach 207 mg/g. The kinetics of phenol adsorption followed nicely the pseudo-second-order rate expression. In the adsorption isotherm, the Langmuir model fit better than the Freundlich model in phenol adsorption. This study suggests that nitrogen-enriched activated carbon prepared from wood fiberboard waste can be used effectively for removal of phenol compounds from aqueous solutions
Time and spatial distribution of multidrug-resistant tuberculosis among Chinese people, 1981–2006: a systematic review
SummaryObjectivesWe aimed to investigate trends in the prevalence of multidrug-resistant tuberculosis (MDR-TB) among Chinese people from first report to 2006, and to detect the high prevalence regions in order to guide control efforts.Materials and methodsThe CBM, VIP, CNKI, and MEDLINE databases were searched through both keywords and subject headings. The literature was screened, and two investigators assessed the quality and extracted the data. Trends in MDR-TB prevalence in three groups – primary, acquired, and combined MDR-TB – were examined separately, using the Cochran–Armitage trend test. Differences were tested with the Kruskal–Wallis test. High prevalence provinces were explored through comparison of the 95% confidence interval (95% CI) with the national average level.ResultsOverall 169 studies were included, with 165 in Chinese and four in English. One hundred and sixteen studies concerned primary MDR-TB, 103 acquired MDR-TB, and 130 combined MDR-TB, with total positive Mycobacterium tuberculosis (MTB) isolates of 110 076, 25 187, and 150 233, respectively. The prevalences of MDR-TB in the three groups in 2005 were 2.64-, 6.20-, and 3.84-times that of 1985, respectively, all showing an upward trend (p<0.05). The prevalences among the three groups were significantly different (p<0.05), with acquired drug resistance (27.5%, 95% CI 26.9–28.1%) much higher than primary drug resistance (4.3%, 95% CI 4.2–4.4%), and combined resistance (9.9%, 95% CI 9.8–10.1%) in between. The top three prevalence regions for primary, acquired, and combined MDR-TB were distributed in the zone from the northeast to the southwest of China, with Hebei, Tibet, and Shanxi having an extremely high prevalence.ConclusionsThe prevalence of MDR-TB among the Chinese people has shown an upward trend since 1985. It is necessary to continue to monitor this trend in China. Special attention should be paid to provinces distributed in the zone from the northeast to the southwest of China for MDR-TB surveillance, research, and control
Prevalence of insomnia symptoms and their associated factors in patients treated in outpatient clinics of four general hospitals in Guangzhou, China
Background: Data on the prevalence of insomnia symptoms in medical outpatient clinics in China are lacking. This study examined the prevalence of insomnia symptoms and their socio-demographic correlates in patients treated at medical outpatient clinics affiliated with four general hospitals in Guangzhou, a large metropolis in southern China.
Method: A total of 4399 patients were consecutively invited to participate in the study. Data on insomnia and its socio-demographic correlates were collected with standardized questionnaires.
Results: The prevalence of any type of insomnia symptoms was 22.1% (95% confidence interval (CI): 20.9–23.3%); the prevalence of difficulty initiating sleep was 14.3%, difficulty maintaining sleep was 16.2%, and early morning awakening was 12.4%. Only 17.5% of the patients suffering from insomnia received sleeping pills. Multiple logistic regression analysis revealed that male gender, education level, rural residence, and being unemployed or retired were negatively associated with insomnia symptoms, while lacking health insurance, older age and more severe depressive symptoms were positively associated with insomnia symptoms.
Conclusions: Insomnia symptoms are common in patients attending medical outpatient clinics in Guangzhou. Increasing awareness of sleep hygiene measures, regular screening and psychosocial and pharmacological interventions for insomnia are needed in China.
Trial registration: ChiCTR-INR-16008066. Registered 8 March 2016
Chemical Mixture Methodology (CMM): Using 15 Health Code Numbers
The Chemical Mixture Methodology (CMM) is used for an emergency response and safety planning for chemical mixtures that cause irreversible or serious health effects. There are three major components of the CMM: Health Code Numbers (HCNs), the Hazard Index, and the Protective Action Criteria values. The HCNs are akin to medical diagnostic codes; they categorize the adverse health outcome that could be induced by exposure to an individual hazardous chemical. Currently, 60 HCNs are used in the CMM to characterize potential health effects for over 3,000 chemicals. Chemicals may have one or more HCNs; however, a maximum of 10 HCNs may be listed in the CMM dataset for each chemical. The HCNs for each chemical are ranked based on their seriousness and the impact of the health effect on a person’s ability to take protective action, with the most serious being included in the CMM. Many chemicals in the CMM dataset have 10 HCNs. This study explored how CMM results would vary if an additional five HCNs were allowed, if needed, for each chemical. A total of 361 common chemicals from the CMM dataset were updated to include up to five additional HCNs. To evaluate the 15-HCN approach, we used 127 test mixtures and each mixture was assessed using three different concentration distributions. This provided a total of 381 test cases in our assessment. Comparing results using the 15-HCN approach to those using the 10-HCN approach, showed no substantial difference in CMM results. This suggests that it may not be necessary to include more HCNs in the CMM dataset. The CMM team continues to update the CMM to support its many users in the United States and around the world. For further information on the CMM, visit http://orise.orau.gov/emi/scapa/chem-mixture-methodolgy/default.htm
Using In Situ Liquid Single Photon Ionization Mass Spectrometry (SPI-MS) to Probe Lithium Polysulfide Electrolyte in Motion
The solid-liquid (s-l) interface is the most common interface encountered in electrochemical systems. The s-l interface has wide applications in energy storage, catalysis, and material sciences. In situ studies of chemical reactions taking place on the s-l interfaces can further our understanding of electron transfer and link to real-world device functions under challenging conditions. Direct probing of the solid electrode and liquid electrolyte interface has been realized using a vacuum compatible electrochemical microfluidic reactor, system for analysis at the liquid vacuum interface (SALVI) with time-of-flight secondary ion mass spectrometry (ToF-SIMS). Most recently, the electrochemical version of SALVI was integrated to the synchrotron based single photon ionization mass spectrometry (SPI-MS). SPI-MS has proven to be a versatile technique for analysis of organic species in the solid or gas phase due to its nature of soft ionization. As a practical example, three different lithium polysulfide electrolytes, Li2S4, Li2S6, and Li2S8, were studied under dynamic conditions with various applied voltages. It was found that despite some PDMS interference peaks such as 369 m/z, unique peaks of interest signifying the electron transfer of the LixSy electrolytes can be identified according to the SPI-MS mass spectra. The observation of in situ compositional changes as a result of electrochemical reaction that take place at the s-l interface in a three electrode system allowed us to piece all the fragments together and identify the compound present in the sample at different stages of photoionization energy (PIE) values. Moreover, we demonstrate that liquid SPI-MS technique has been enabled to study dynamic electron transfer of LixSy electrolytes using real-time molecular imaging
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