Complex genotype-phenotype correlation of MYH11: new insights from monozygotic twins with highly variable expressivity and outcomes.

BACKGROUND: Thoracic aortic aneurysm/dissection (TAAD) and patent ductus arteriosus (PDA) are serious autosomal-dominant diseases affecting the cardiovascular system. They are mainly caused by variants in the MYH11 gene, which encodes the heavy chain of myosin 11. The aim of this study was to evaluate the genotype-phenotype correlation of MYH11 from a distinctive perspective based on a pair of monozygotic twins. METHODS: The detailed phenotypic characteristics of the monozygotic twins from the early fetal stage to the infancy stage were traced and compared with each other and with those of previously documented cases. Whole-exome and Sanger sequencing techniques were used to identify and validate the candidate variants, facilitating the analysis of the genotype-phenotype correlation of MYH11. RESULTS: The monozygotic twins were premature and presented with PDA, pulmonary hypoplasia, and pulmonary hypertension. The proband developed heart and brain abnormalities during the fetal stage and died at 18 days after birth, whereas his sibling was discharged after being cured and developed normally post follow-up. A novel variant c.766 A > G p. (Ile256Val) in MYH11 (NM_002474.2) was identified in the monozygotic twins and classified as a likely pathogenic variant according to the American College of Medical Genetics/Association for Molecular Pathology guidelines. Reviewing the reported cases (n = 102) showed that the penetrance of MYH11 was 82.35%, and the most common feature was TAAD (41.18%), followed by PDA (22.55%), compound TAAD and PDA (9.80%), and other vascular abnormalities (8.82%). The constituent ratios of null variants among the cases with TAAD (8.60%), PDA (43.8%), or compound TAAD and PDA (28.6%) were significantly different (P = 0.01). Further pairwise comparison of the ratios among these groups showed that there were significant differences between the TAAD and PDA groups (P = 0.006). CONCLUSION: This study expands the mutational spectrum of MYH11 and provides new insights into the genotype-phenotype correlation of MYH11 based on the monozygotic twins with variable clinical features and outcomes, indicating that cryptic modifiers and complex mechanisms beside the genetic variants may be involved in the condition.

[The characteristics and change trends of air pollutants in Lanzhou City from 2014 to 2020].

OBJECTIVE: To study the distribution characteristics of atmospheric pollutants and their correlation with meteorological factors. METHODS: The PM_(2.5), PM_(10), NO_2, SO_2, O_(3-1 h), O_(3-8 h) and CO daily average concentration data from 2014 to 2020 were obtained from Lanzhou Environmental Protection Bureau. The interannual changes of pollutants, monthly changes, seasonal changes and trend of spatial distribution were analysed. Spearman correlation analysis was performed on the relationship among pollutants. RESULTS: The main pollutants exceeding the standard in Lanzhou from 2014 to 2020 were PM_(10), PM_(2.5) and NO_2, average annual concentration of PM_(10), PM_(2.5), NO_2 and CO were decreasing year by year, and O_3 was increasing year by year. The monthly average concentration of PM_(10) was the highest in December, January, March and November were the second highest, and it was higher in February, April and May. The monthly change trends of PM_(2.5), NO_2, SO_2 and CO concentrations were the same, and the monthly change trends of the 1 hour average and daily maximum 8-hour average concentrations of O_3 were the same. The seasonal variation of atmospheric pollutant concentration was obvious, the concentrations of PM_(10), PM_(2.5), SO_2, NO_(2 )and CO were the highest in winter and the lowest in summer. O_3 concentration was the highest in summer and lowest in winter. Average annual concentration of 6 pollutants in different regions had statistically significant differences(H=750.40, 1112.99, 1410.05, 352.04, 360.17, 619.20, 729.52; P<0.001). Among them, the average annual concentration of PM_(10), PM_(2.5), SO_(2 )and O_(3-1 h) in Xigu District were the highest. PM_(10), PM_(2.5), NO_2, SO_2, CO average annual concentration were negatively correlated with temperature and wind speed(r_s=-0.423, -0.561, -0.395, -0.660, -0.569, -0.043, -0.094, -0.130, -0.172, -0.135), the concentration of PM_(10), PM_(2.5), O_3, SO_2 concentration were negatively correlated with humidity(r_s=-0.238, -0.121, -0.110, -0.094), only O_3 was positively correlated with temperature(r_s=0.486). CONCLUSION: The primary pollutants in Lanzhou from 2014 to 2020 were PM_(10), PM_(2.5) and NO_2.O_3 had an obvious upward trend year by year. The 6 pollutants had obvious seasonal changes and regional distribution characteristics. Some pollutants had the same homology, and meteorological factors affected each pollution. The concentration of the substance had an important influence. Relevant air pollution control measures should be formulated based on the main excessive pollutants, the monthly change trend of air pollution and the seasonal pollution characteristics, the same emission sources and geographical distribution characteristics should be considered, and the meteorological factors should be combined.

[Trend of atmosphreic PM_(2. 5) and their components in two districts of Lanzhou City from 2015 to 2019].

OBJECTIVE: To analyse the variation of the fine particulate matter(PM_(2. 5)) concentration and its chemical composition in two districts of Lanzhou City from 2015 to 2019. METHODS: From January 2015 to December 2019, two sampling points, namely residential district(Chengguan District) and industrial district(Xigu District) were selected in Lanzhou City, to collect PM_(2. 5) samples, and the mass concentrations, metals and metalloid elements, water-soluble ions and polycyclic aromatic hydrocarbons(PAHs) contents were determined. RESULTS: A total of 838 samples were collected in Chengguan District and Xigu District in Lanzhou City during 2015-2019, the average annual mass concentration and the daily average concentration of the PM_(2. 5) were decreasing year by year(P<0. 05). The higher metal content in PM_(2. 5) were Al, Pb, Mn and As during 2015-2019. Sb, Al, As, Cd, Cr, Pb, Mn and Tl element content were higher in 2015 and 2016 than in other years(P<0. 05), the average annual concentration of As were 7. 92 and 8. 63 ng/m~3 respectively, which exceeded the reference concentration limit of the ambient air quality standard. The average annual mass concentration of Cr from 2015 to 2019 was much higher than the annual average reference concentration limit of the ambient air quality standard. From 2015 to 2019, except for 2018, the highest average concentration of PAHs in atmospheric PM_(2. 5) in the two districts of Lanzhou City was Ant, B(b)F and I(cd)P mass concentration were highest in 2015, N(a)P, FI, Ace, Phe, Ant, Flu, Pyr, B(k)F and B(a)P mass concentration were highest in 2017, Acy, Chr and B(ghi)P mass concentration were highest in 2018(P<0. 05). From 2017 to 2018, the average annual content of B(a)P in the two districts of Lanzhou City were 1. 16 and 1. 11 ng/m~3, respectively, which exceeded the annual average concentration limit of the ambient air quality standard. The concentration of Cl~- in PM_(2. 5) in the two districts of Lanzhou City was decreasing year by year, the annual average concentrations of SO~2-_4, NO~-_3 and NH~+_4 from 2017 to 2019 showed a downward trend year by year. SO~2-_4, Cl~- of both districts were the highest in 2015, and NO~-_3, NH~+_4 were the highest in 2017(P<0. 05). CONCLUSION: The air quality of Lanzhou City has been improved obviously, but the pollution problem is still serious.

Rapid and quantitative detection of Shiga toxin1 and Shiga toxin2 based on multiple targets UPT-LF assay.

Shiga toxin-producing Escherichia coli (STEC) infection causes a series of diseases that are highly pathogenic and deadly in humans and animals, seriously endangering public health. Of the pathogenic factors within STEC, the two groups of Shiga toxin (Stx) consisting Stx1 and Stx2 plays a prominent role in the pathogenesis of STEC infection. In this study, we developed single-target up-converting phosphor technology-based lateral flow assay (Stx-UPT-LFA) for the rapid detection of Stx1 and Stx2, respectively, and also developed a dual-target Stx1/2-UPT-LFA based on single-target strips to detect of Stx1 and Stx2 at the meantime within 20 min. We choose the purified Stx1 and Stx2 standard samples, and the optimum monoclonal antibody (namely 8E7-E6, 2F6-F8 for Stx1 and S1D8, S2C4 for Stx2) were selected for use in Stx-UPT-LFA in double-antibody-sandwich mode. The sensitivities of single-target Stx-UPT-LFA for both Stx1 and Stx2 were 1 ng mL-1 with accurate quantitation ranges of 1-1000 ng mL-1 and 1-800 ng mL-1 respectively. No false-negative result was found in the Stx2-UPT-LFA even with a high-test concentration up to 1000 ng mL-1. Meanwhile, both targets detection sensitivities for dual-target Stx1/2-UPT-LFA were 5 ng mL-1, and accurate quantitation ranges were 5-1000 ng mL-1 and 5-800 ng mL-1 for standard Stx1 and Stx2 solutions without cross-interference between two targets. Both techniques showed good linearities, with a linear fitting coefficient of determination(r) of 0.9058-0.9918. Therefore, the UPT-LFA could realize simultaneous detection for multiple targets on a single strip and thus to quickly determine the type of infectious Stxs. In addition, the single-target Stx1-UPT-LFA and Stx2-UPT-LFA showed excellent specificity to six toxins, even at high concentrations of 1000 ng mL-1. In conclusion, the developed Stx-UPT-LFA allows the rapid, quantitative, reliable and simultaneous detection of Stx1 and Stx2 within 20 min, providing an alternative method for clinical diagnosis of STEC infection.

Rapid detection of severe fever with thrombocytopenia syndrome virus (SFTSV) total antibodies by up-converting phosphor technology-based lateral-flow assay.

In this study, an up-converting phosphor technology-based lateral-flow (UPT-LF) assay was developed to detect severe fever with thrombocytopenia syndrome virus (SFTSV) total antibodies rapidly and specifically. SFTSV recombinant N protein (SFTSV-rNP) was coated on analytical membrane for sample capture, up-converting phosphor (UCP) particles were used as the reporter, the luminescence emitted by UCP particles was converted to a measurable signal by a biosensor. The performance of UPT-LF assay was evaluated by testing 302 field serum samples by ELISA (enzyme-linked immunosorbent assay), Western blotting and UPT-LF assay. UPT-LF assay exhibited a lower detection limit than ELISA, and a satisfied level of agreement was exhibited by Kappa statistics (Kappa coefficient = 0.938). Considering Western blotting as the reference for comparison, the sensitivity and specificity of UPT-LF assay could reach 98.31% and 100%. UPT-LF assay showed no specific reaction with hantavirus total serum antibodies, which avoids the misdiagnosis of SFTSV from hantavirus that could cause similar clinical symptoms. UPT-LF assay was able to achieve acceptable results within 15 min and needed only 10 µL sample for each test. As a whole, UPT-LF assay is a candidate method for on-site surveillance of SFTSV total antibodies owing to its excellent sensitivity, specificity, stability, easy operation and for being less time consuming.

Cold stress provokes lung injury in rats co-exposed to fine particulate matter and lipopolysaccharide.

Cold exposure aggravates respiratory diseases, which are also influenced by the exposures to particulate matter and endotoxin in the air. The aim of this study was to investigate the potential interactions among cold stress, fine particulate matter (PM2.5, particles with aerodynamic diameter of 2.5 µm or less) and lipopolysaccharide (LPS, pure chemical form of endotoxin) on rat lung and to explore the related possible mechanisms of the interactions. Wistar rats were randomly grouped to be exposed to, 1) normal saline (0.9% NaCl), 2) PM2.5, 3) LPS, and 4) PM2.5 and LPS (PM2.5 + LPS) through intratracheal instillation under cold stress (0 °C) and normal temperature (20 °C). Lung function, lung tissue histology, inflammatory response and oxidative stress levels were measured to examine the lung injury and to investigate the potential mechanisms. Exposure to PM2.5 or LPS substantially changed pulmonary function [indicated by peak inspiratory flow (PIF) and peak expiratory flow (PEF)], inflammatory cytokine levels [indicated by interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α)] and lung histology, compared to the non-exposed groups. Exposure to PM2.5 + LPS under cold stress induced the most significant changes, including the increases of IL-6, TNF-α and thiobarbituric acid-reactive substances (TBARS), the decreases of PIF and PEF and more severe lung injury, among all exposure scenarios. Glutathione peroxidase activity and, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were found to be suppressed under cold stress, whereas Nrf2 and HO-1 levels were observed to be upregulated by exposure to PM2.5 or LPS under normal temperature. In conclusion, cold stress may aggravate the lung injury in rats induced by simultaneous exposure to PM2.5 and LPS. The progress may involve the suppressing of Nrf2/HO-1 signal pathway.

An up-converting phosphor technology-based lateral flow assay for point-of-collection detection of morphine and methamphetamine in saliva.

Morphine (Mop) and methamphetamine (Met) are highly addictive drugs worldwide. Point-of-collection testing (POCT) for drug-of-abuse screening is important in abuse/rehabilitation clinics and law-enforcement agencies. We established an up-converting phosphor technology-based lateral flow assay (UPT-LFA) as a point-of-collection testing (POCT) method, namely Mop-UPT-LFA and Met-UPT-LFA, for the detection of morphine and methamphetamine without complicated sample pre-treatment, respectively, in saliva. The sensitivities of the Mop-UPT-LFA and the Met-UPT-LFA were 5 and 10 ng mL-1 with accurate quantitation of 5-100 ng mL-1 and 10-250 ng mL-1 for morphine and methamphetamine, respectively, for a detection time of 15 min. In reference to the detection limits of 20 and 25 ng mL-1 for morphine and methamphetamine, respectively, in the Driving Under the Influence of Drugs, Alcohol and Medicines (DRUID) program of the European Union, the percentage test/control (T/C) ratio of the UPT-LFA between 2 and 15 min reached 101% and 86%, and the UPT-LFA produced accurate qualitative results in 2 min for 100 simulated-saliva samples with the exception of a few weakly positive samples. The sample and sample treating buffer were mixed and added to the test strip, and the test was conducted 15 min later. Although we found no significant difference between the UPT-LFA quantitative test and the liquid chromatography tandem mass spectrometry (LC-MS) test, compared with the latter, the UPT-LFA was substantially faster and had higher detection efficiency. The UPT-LFA showed more accurate qualitative results than the LC-MS for 50 simulated-saliva samples. The ease of operation, high sensitivity, and accuracy of the UPT-LFA make it a valid candidate POCT method for drug-of-abuse screening.

Increased NGAL level associated with iron store in chronic kidney disease with anemia.

An iron scarcity often occurs in chronic kidney disease (CKD). Neutrophil gelatinase-associated lipocalin (NGAL), a biomarker of acute kidney injury, is associated with iron metabolism. The present study determined the association between serum NGAL and iron status in chronic kidney disease with anemia. A total of 154 adult CKD patients were divided into anemia and without anemia groups. The anemia groups were further subdivided into two groups based on the presence or absence of iron deficiency, defined as a transferrin saturation (TSAT) < 20%. The NGAL was measured for all the 154 patients, and the possible relationships with iron status were analyzed. 27.7% patients with TSAT < 20% presented lower hemoglobin, serum iron, serum ferritin, and higher NGAL values than those without iron deficiency. NGAL was inversely correlated with hemoglobin, hematocrit, MCV, MCH, serum iron, and TSAT. NGAL adequately diagnosed the status of iron deficiency among CKD patients by ROC analysis. The optimal NGAL cutoff value able to identify iron deficiency was found to be > 244.8 ng/mL, with 73.01% sensitivity and 68.29% specificity. CKD patients with anemia presented altered NGAL values as this protein is involved in the maintenance of iron balance. Thus, NGAL might be proposed as a new tool for assessing the iron deficiency and in the management of iron therapy for CKD patients.

COPD rat model is more susceptible to cold stress and PM2.5 exposure and the underlying mechanism.

The purpose of this study is to verify the hypothesis that chronic obstructive pulmonary disease (COPD) model rat is more susceptible to cold stress and fine particulate matter (PM2.5) exposure than the healthy rat, and explore the related mechanism. COPD rat model, established with cigarette smoke and lipopolysaccharide intratracheal instillation, were exposed to cold stress (0 °C) and PM2.5 (0, 3.2, 12.8 mg/ml). After that, the levels of superoxide dismutase, inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), monocyte chemotactic protein 1 (MCP-1) and angiotensin Ⅱ (Ang-Ⅱ) in lung were measured, as well as the expression levels of lung 8-hydroxy-2-deoxyguanosine (8-OHdG), nuclear factor kappa B (NF-κB), heme-oxygenase-1 (HO-1) and nuclear factor erythroid-2-related factor 2 (Nrf2). There were significant positive relationships between PM2.5 and lung level of iNOS, TNF-α, MCP-1 and Ang-Ⅱ, lung function and pathologic damage in COPD rats. The HO-1, NF-κB and 8-OHdG were found highly expressed in COPD rat lung, particularly at the higher PM2.5 dose of cold stress groups, while Nrf2 was found declined. Thus, COPD rats may be more susceptible to cold stress and PM2.5 exposure. Cold stress may aggravate PM2.5-induced toxic effects in the lung of COPD rats through increasing Ang-Ⅱ/NF-κB signaling pathway and suppressing Nrf2 signaling pathway.

The probable roles of valsartan in alleviating chronic obstructive pulmonary disease following co-exposure to cold stress and fine particulate matter.

Angiotensin II (ANG II) might play an important role in the co-effects of cold stress and fine particulate matter (PM2.5) on chronic obstructive pulmonary disease (COPD). The purpose of this study is to evaluate the roles of valsartan in alleviating COPD following co-exposure to cold stress and PM2.5. Both the two intervention factors are carried out upon COPD rats with the intervention of valsartan. Blockade of angiotensin receptor by valsartan decreases the levels of malondialdehyde in the normal temperature and tumor necrosis factor-α under cold stress significantly. When treated with valsartan and PM2.5 simultaneously, the expression of 8-hydroxy-2-deoxyguanosine, nuclear factor kappa B and heme oxygenase-1 decrease significantly in the group of cold stress. In conclusion, these results indicate that valsartan might relieve the co-effects of cold stress and PM2.5 on COPD rat lung to some degree.

[Effect of early caffeine treatment on the need for respirator therapy in preterm infants with respiratory distress syndrome].

OBJECTIVE: To study the efficacy of early caffeine treatment in preterm infants with respiratory distress syndrome (RDS). METHODS: A prospective controlled clinical trial was performed. A total of 59 preterm infants with RDS were enrolled and divided into a caffeine group (30 infants) and a control group (29 infants). Caffeine was administered in the caffeine group and control group at the same dosage at 12-24 hours after birth and before extubation respectively. The respirator parameters and the incidence rates of ventilator-associated pneumonia (VAP) and apnea were compared between the two groups. RESULTS: Compared with the control group, the caffeine group had significantly lower peak inspiratory pressure, peak fraction of inspired oxygen, and incidence rate of VAP (p<0.05), as well as significantly shorter intubation time, NCPAP time, and total duration of oxygen supply (p<0.05). In addition, the caffeine group had a significantly longer time to first onset of apnea after extubation (p<0.05) and significantly fewer times of onset of apnea 1-2 days after extubation (p<0.01), as compared with the control group. CONCLUSIONS: Early caffeine treatment can reduce the need for assisted ventilation in preterm infants with RDS, help with early extubation and ventilator weaning, reduce the oxygen time in the late stage, reduce the incidence of VAP, and prevent the development of apnea after extubation.