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2.
J Thorac Dis ; 16(3): 2070-2081, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38617762

ABSTRACT

Background: Electrical impedance tomography (EIT) is a relatively recent functional imaging technique that is both noninvasive and radiation free. EIT measures the associated voltage when a weak current is applied to the surface of the human body to determine the distribution of electrical resistance within tissues. We performed a bibliometrics-based review to explore the geographic hotspots of current research and future trends developing in the field of EIT for mechanical ventilation. Methods: The Web of Science database was searched from its inception to June 25, 2023. CiteSpace software was used to visualize and analyze the relevant literature and identify the most impactful literature, trends, and hotspots. Results: 363 articles describing EIT use in mechanical ventilation were identified. A fluctuating growth in the number of publications was observed from 1998 to 2023. Germany had the highest number of articles (n=154), followed by Italy (n=53) and China (n=52). A cluster analysis of keyword co-occurrence revealed that "titration", "ventilator-related lung injury", and "oxygenation" were the most actively researched terms associated with the use of EIT in mechanically ventilated patients. Conclusions: Significant progress has been made in EIT research for mechanical ventilation. EIT research is limited to a small number of countries with a present research focus on the prevention and treatment of ventilator-related lung injury, oxygenation status, and prone ventilation. These topics are expected to remain research hotspots in the future.

3.
Micromachines (Basel) ; 15(3)2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38542630

ABSTRACT

In this manuscript, a broadband transmitarray antenna (TA) using a metasurface-based element is presented for millimeter-wave communication applications. The metasurface-based TA element adopts a receiver-transmitter configuration: metasurfaces are applied as the receiver and transmitter, and slot-coupled differentially fed striplines are used as the phase compensation. The designed TA element achieves good transmission performance with a more than 360° transmission phase shift range and less than 1-dB transmission insertion loss within a wide frequency range. To verify the proposed TA, a prototype is fabricated based on the conventional printed circuit board (PCB) process, and a pyramid horn is designed as the source. The measured results show that the proposed TA with the differential feed network presents a 1-dB gain bandwidth of 26.2% from 23.5 to 30.5 GHz and a peak gain of 24.5 dBi. The designed TA is a promising alternative for millimeter-wave communications applications because of its high gain, broad bandwidth, low costs, and convenient integration with other circuits.

5.
BMC Pregnancy Childbirth ; 23(1): 766, 2023 Nov 02.
Article in English | MEDLINE | ID: mdl-37919654

ABSTRACT

BACKGROUND: This study aimed to investigate the effect of the pathological staging of acute histological chorioamnionitis (HCA) on laboratory indicators and to conduct further studies to reassess the threshold values used by clinicians to identify acute HCA in febrile parturients undergoing epidural analgesia. METHODS: A retrospective study of febrile mothers receiving epidural analgesia at Nanjing Maternal and Child Health Care Hospital from January 1, 2018 to December 31, 2018. The participants were grouped by the progression of acute HCA, and the laboratory parameters were compared between groups. The ability of C-reactive protein (CRP), neutrophil-lymphocyte ratio (NLR), monocyte-lymphocyte ratio (MLR), and monocyte-leukocyte ratio (M%), alone or in combination, to identify acute HCA in febrile parturients undergoing epidural analgesia was assessed using logistic regression and ROC curves. RESULTS: The area under the curve (AUC) of the best logistic regression model predicting HCA climbed to 0.706 (CRP + MLR). Maternal CRP, NLR, and MLR significantly and progressively increased with the progression of acute HCA (p < 0.0001). Based on the ROC curves, the following thresholds were selected to define increased laboratory indicators for identifying acute HCA: CRP ≥ 6.90 mg/L, NLR ≥ 11.93, and MLR ≥ 0.57. In addition, the AUC of the best logistic regression model predicting HCA ≥ stage 2 was 0.710, so these inflammatory markers were more precise in predicting HCA ≥ stage 2. CONCLUSION: Increased CRP (≥ 6.90 mg/L), NLR (≥ 11.93), and MLR (≥ 0.57) may help clinicians to identify early potential acute HCA in febrile parturients receiving epidural analgesia and to monitor progression to optimize clinical treatment options. TRIAL REGISTRATION: The study was registered in the Chinese Clinical Trial Registry on November 24, 2021 ( http://www.chictr.org.cn , ChiCTR2100053554).


Subject(s)
Analgesia, Epidural , Chorioamnionitis , Pregnancy , Female , Child , Humans , Retrospective Studies , Chorioamnionitis/diagnosis , Biomarkers , Lymphocytes , Neutrophils , C-Reactive Protein/analysis
6.
PeerJ ; 11: e14907, 2023.
Article in English | MEDLINE | ID: mdl-36846465

ABSTRACT

Introduction: Previous studies have explored factors that influence the occurrence of hypothermia in very low/extremely low birth weight (VLBW/ELBW) infants, but the factors associated with hypothermia in VLBW or ELBW infants remain inadequately evaluated due to limited prospective data and inconsistency in study populations. Therefore, it is necessary to systematically evaluate the risk factors of hypothermia in VLBW/ELBW infants in order to provide a theoretical basis for clinical practice. Methods: PubMed and other databases were used to search for case-control or cohort studies on factors influencing the occurrence of hypothermia in VLBW/ELBW infants. The search time was set from database creation to June 30th, 2022. Literature screening, quality evaluation, and data extraction were performed independently by two investigators according to predefined inclusion and exclusion criteria. Meta-analysis was performed using RevMan 5.3. Results: A total of 10 papers were finally included in this study and 12 factors were established by meta-analysis: body weight (six papers), failure to keep warm in time (three papers), neonatal resuscitation (seven papers), gestational age (three papers), premature rupture of membranes (three papers), maternal combined complications (four papers), cesarean section (six papers), antenatal steroids (four papers), multiple birth (two papers), small for gestational age (two papers), 1 min Apgar score (three papers), and 5 min Apgar score (three papers). Since only one study included race, age (hour), socio-economic status, and spontaneous labor, these factors could not be fitted into RevMan 5.3 for the analysis. Conclusion: Although there were differences in the study design of the included literature, the influencing factors described in each study were relatively similar. The influencing factors identified in this study may contribute to the construction of related intervention strategies for hypothermia in VLBW/ELBW infants.


Subject(s)
Hypothermia , Infant, Extremely Low Birth Weight , Infant, Newborn , Humans , Female , Pregnancy , Prospective Studies , Hypothermia/etiology , Cesarean Section , Resuscitation
7.
Front Microbiol ; 13: 832151, 2022.
Article in English | MEDLINE | ID: mdl-35495651

ABSTRACT

Background: Inulin-type fructans (ITF) have been used as prebiotics to alleviate glucose and lipid metabolism disorders. However, few studies evaluated the microbial mechanism of ITF in improving maternal metabolic status during pregnancy. Methods: C57BL/6J mice were fed a high-fat/sucrose diet (HFD) for 4 weeks before and throughout pregnancy to induce a model of gestational diabetes mellitus (GDM). Body weight, glycolipid metabolic parameters, and fecal short-chain fatty acids (SCFAs) were assessed in the experimental process. The effects of ITF on the fecal microbiota were analyzed by 16S rRNA gene amplicon sequencing. Results: Pregnant HFD-fed mice displayed significant insulin resistance and dyslipidemia. ITF (3.33 g/kg/day) treatment improved glucose and lipid metabolism disorder parameters in HFD-induced GDM mice and alleviated fat accumulation and glucose intolerance. The alpha diversity of the gut microbial community was increased in ITF mice, while the beta diversity returned to the level of normal chow diet (NCD) mice. Interestingly, Verrucomicrobia, Bifidobacterium, and Akkermansia were obviously enriched, while Dubosiella was obviously lessened after inulin treatment. Further analysis indicated that Dubosiella was positively correlated with markers of glycolipid metabolism disorders, whereas the ITF-supplemented diet partially reversed the changes. Conclusion: Our results suggest that the ITF treatment may alleviate glucose and lipid metabolism disorders with the mediation of gut microbiota.

8.
Microb Pathog ; 166: 105555, 2022 May.
Article in English | MEDLINE | ID: mdl-35487480

ABSTRACT

Vulvovaginal candidiasis (VVC), a major gynecological disease with high recurrence rate, increases the risk of abortion, intrauterine infection, premature rupture of membranes, and premature birth in pregnancy. However, the exact pathogenesis of this disease has yet to be elucidated. To facilitate understanding of the pathogenesis of VVC in pregnancy, this study sought to establish an animal model of vaginal infection with Candida albicans in pregnant mice. Female mice were mated with male mice, and female mice were infected with C. albicans at E4.5 (embryonic day 4.5). The weight and abortion rate of pregnant mice at E0.5, E4.5, E8.5, E11.5, and E18.5 were recorded, respectively, as well as the weights of fetus and placenta on E18.5. Fetal weight at E18.5 and the weight growth rate in the experimental mice was lower than those in the control mice, but the placenta weight at E18.5 and the abortion rate in the experimental mice were increased with those of the control mice. Hematoxylin-eosin (H&E) staining, Gomori-Grocott staining and vaginal lavage culturing were conducted to verify that the experimental mice were infected with C. albicans. Differentially expressed gene IL-15 was screened out by polymerase chain reaction (PCR) array between the two groups. Enzyme-linked immunosorbent assay (ELISA) showed that IL-15 expression in plasma of the mice was decreased in the experimental group compared with the control group. RT-qPCR confirmed that IL-15 mRNA expression was increased in placental tissues, while mRNA expression of IL-15R/JAK1-JAK3/PI3K/PDK1/AKT/P70S6K-mTOR was decreased in placental tissues. In conclusion, this study demonstrated that VVC in BALB/c pregnant mice led to a series of adverse pregnancy outcomes that were related to changes in IL-15 and its downstream signaling pathways, which may indicate a potential therapy for VVC during pregnancy in humans.


Subject(s)
Candidiasis, Vulvovaginal , Interleukin-15 , Animals , Candida albicans/genetics , Candidiasis, Vulvovaginal/pathology , Female , Humans , Interleukin-15/genetics , Male , Mice , Mice, Inbred BALB C , Placenta/pathology , Pregnancy , Pregnancy Outcome , RNA, Messenger
9.
Int J Mol Sci ; 23(3)2022 Feb 04.
Article in English | MEDLINE | ID: mdl-35163707

ABSTRACT

Tyrosine kinase inhibitor (TKI) therapy has greatly improved lung cancer survival in patients with epidermal growth factor receptor (EGFR) mutations. However, the development of TKI-acquired resistance is the major problem to be overcome. In this study, we found that miR-196a expression was greatly induced in gefitinib-resistant lung cancer cells. To understand the role and mechanism of miR-196a in TKI resistance, we found that miR-196a-forced expression alone increased cell resistance to gefitinib treatment in vitro and in vivo by inducing cell proliferation and inhibiting cell apoptosis. We identified the transcription factor nuclear factor erythroid 2-related factor 2 (NRF2) bound to the promoter region of miR-196a and induced miR-196a expression at the transcriptional level. NRF2-forced expression also significantly increased expression levels of miR-196a, and was an upstream inducer of miR-196a to mediate gefitinib resistance. We also found that glycolipid transfer protein (GLTP) was a functional direct target of miR-196a, and downregulation of GLTP by miR-196a was responsible for gefitinib resistance. GLTP overexpression alone was sufficient to increase the sensitivity of lung cancer cells to gefitinib treatment. Our studies identified a new role and mechanism of NRF2/miR-196a/GLTP pathway in TKI resistance and lung tumor development, which may be used as a new biomarker (s) for TKI resistance or as a new therapeutic target in the future.


Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Carrier Proteins/genetics , Drug Resistance, Neoplasm , Gefitinib/pharmacology , MicroRNAs/genetics , NF-E2-Related Factor 2/metabolism , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Apoptosis , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/physiopathology , Cell Line, Tumor , Cell Proliferation , Female , Gefitinib/therapeutic use , Gene Expression Regulation, Neoplastic , Humans , Mice , Mice, Nude , MicroRNAs/metabolism , Xenograft Model Antitumor Assays
10.
J Clin Lab Anal ; 36(1): e24050, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34786765

ABSTRACT

BACKGROUND: Maternal intrapartum fever has a serious impact on mother and child. However, the corresponding study seems to be in short. METHODS: The role of inflammatory cells in patients who were diagnosed with intrapartum fever lived in part of Eastern China was evaluated. The obstetrics outcomes, complete blood cell count (CBC) and thereby converted neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio, monocyte to lymphocyte ratio (MLR), and vaginal secretion were compared in different groups. RESULTS: Prepartum values of white blood cell (WBC), red blood cell (RBC), and hemoglobin (Hb) were all a little higher in the febrile group than in the afebrile group, and postpartum WBC in the afebrile group was still higher while postpartum RBC and Hb were inferior to non-fever maternity. Postpartum NLR and MLR were all higher in the fever group but not preferred overtly difference before delivery. Additionally, the comparison of WBC, RBC, Hb, platelets, neutrophils, and monocytes in prepartum and postpartum all showed significant differences. CONCLUSION: The parturition could bring about the value change of CBC and intrapartum fever might aggravate or alleviate this change. Besides, the intrapartum fever might not be caused mainly by infection and the difference between bacteria and fungus could reflect in the CBC.


Subject(s)
Fever , Peripartum Period/physiology , Pregnancy Complications , Adult , Blood Cell Count , China/epidemiology , Cross-Sectional Studies , Female , Fever/epidemiology , Fever/physiopathology , Humans , Infant, Newborn , Parturition , Pregnancy , Pregnancy Complications/epidemiology , Pregnancy Complications/physiopathology , Pregnancy Outcome/epidemiology
11.
Diabetol Metab Syndr ; 13(1): 150, 2021 Dec 24.
Article in English | MEDLINE | ID: mdl-34952629

ABSTRACT

BACKGROUND: Gestational diabetes mellitus (GDM) has significant short and long-term health consequences for both the mother and child. There is limited but suggestive evidence that inulin could improve glucose tolerance during pregnancy. This study assessed the effect of inulin on glucose homeostasis and elucidated the molecular mechanisms underlying the inulin-induced antidiabetic effects during pregnancy. METHOD: Female C57BL/6 mice were randomized to receive either no treatment, high-dose inulin and low-dose inulin for 7 weeks with measurement of biochemical profiles. A real-time2 (RT2) profiler polymerase chain reaction (PCR) array involved in glycolipid metabolism was measured. RESULTS: Inulin treatment facilitated glucose homeostasis in a dose-dependent manner by decreasing fasting blood glucose, advanced glycation end products and total cholesterol, and improving glucose tolerance. Suppressing resistin (RETN) expression was observed in the inulin treatment group and the expression was significantly correlated with fasting blood glucose levels. The ratios of p-IRS to IRS and p-Akt to Akt in liver tissue and the ratio of p-Akt to Akt in adipose tissue as well as the expression level of GLUT4 increased significantly after inulin treatment. CONCLUSIONS: Our findings indicated improvement of glucose and lipid metabolism by inulin was to activate glucose transport through the translocation of GLUT4 which was mediated by insulin signaling pathway repairment due to decreased expression of RETN and enhanced phosphorylation of IRS and Akt in GDM mice.

12.
Front Microbiol ; 12: 651426, 2021.
Article in English | MEDLINE | ID: mdl-33897665

ABSTRACT

Aerobic vaginitis (AV) can occur if normal vaginal microflora are dominated by aerobic bacteria, seriously affects not only female health, but also fetal health while they are pregnant. Besides, pregnant status also aggravates the symptoms and consequences of the infection. Here, we infected pregnant BALB/c mice with Escherichia coli on embryonic day 4.5 (E4.5) (study group), and administered an equivalent volume of phosphate-buffered saline in another cohort of pregnant mice (control group). We recorded the weight of pregnant mice and their fetuses. The maternal and fetal weight of the study group decreased in comparison with that of the control group, whereas the weight of placenta increased in the study group. Then, five genes with significant upregulation and 15 genes with downregulation were screened. Expression of interleukin 4 (IL-4) mRNA in the study group decreased to 18.5%. Enzyme-linked immunosorbent assay results showed IL-4 expression in mouse plasma declined in the study group at E11.5 and E18.5. mRNA expression of chemokine (c-c motif) ligand (CCL)-17, CCL-22, CCL-24, IL-4, Janus Kinase (JAK)-1, signal transducer and activator of transcription (STAT)-6, and GATA-3 showed significant downregulation in placental and uterine tissues. Flow cytometry of primary decidual macrophages (DMs) revealed more M1-like macrophages in the study group. And after addition of IL-4 to DMs, more M1 macrophages polarized to M2 type macrophages. We did not discover bacteria existed in mouse placentas. Our study affords a feasible method for exploring and managing AV during pregnancy.

13.
Mycopathologia ; 186(2): 177-188, 2021 May.
Article in English | MEDLINE | ID: mdl-33587236

ABSTRACT

Vulvovaginal candidiasis (VVC) caused by Candida spp. affects 70-75% of women at least once during their lives. We aim to elucidate the potential mechanism of VVC and investigate the therapeutic effects of long noncoding RNA 9708-1. Female BALB/c mice were randomized to four treatment groups, including the blank control group, VVC control group, vehicle control group and lncRNA 9708-1-overexpressed group. Mice were euthanized on Day 4, Day 7 and Day 14 after treatment. Colony-forming unit (CFU) was measured, and the inflammation was detected by hematoxylin and eosin (H&E). Gene and protein expression levels of lncRNA 9708-1 and FAK were determined by real-time PCR, Western blot and immunohistochemistry. The overexpression of lncRNA 9708-1 significantly decreased the fungal load from Day 4 to 7. H&E staining indicated that the impaired histological profiles were improved in lncRNA 9708-1-overexpressed group. LncRNA 9708-1 led to a significant increase in FAK level of vagina tissue which is expressed mainly in epithelial basal layer. This study suggests that lncRNA 9708-1 played a protective role on murine experimental VVC by upregulating the expression levels of FAK.


Subject(s)
Candidiasis, Vulvovaginal , RNA, Long Noncoding , Animals , Antifungal Agents/therapeutic use , Candida albicans , Candidiasis, Vulvovaginal/drug therapy , Disease Models, Animal , Female , Humans , Mice , Mice, Inbred BALB C , Vagina
14.
Orthop Surg ; 13(2): 458-465, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33491266

ABSTRACT

OBJECTIVE: To evaluate the patellar morphology of trochlear dysplasia and normal knees in different genders and in different severities of trochlear dysplasia on CT scans. METHODS: A total of 75 patients with trochlear dysplasia (110 knees) treated at the Third Hospital of Hebei Medical University from December 2013 to December 2018 were included in an experimental group, and an age-matched and sex-matched cohort of 46 patients with normal trochlear shape (61 knees) were randomly selected into a control group. The experimental group was divided into a female experimental group (Group FE, 47 patients, 72 knees) and a male experimental group (Group ME, 28 patients, 38 knees); the control group was divided into a female control group (Group FC, 31 knees, 24 female patients) and a male control group (Group MC, 30 knees, 22 male patients). Furthermore, according to the severity of trochlear dysplasia, Group FE was divided into a female low-grade dysplasia group (Group FL, 20 knees) and a female high-grade dysplasia group (Group FH, 52 knees); Group ME was divided into a male low-grade dysplasia group (Group ML, 16 knees) and a male high-grade dysplasia group (Group MH, 22 knees). All participants had undergone CT scans in the supine position; the patellar width and thickness, the lateral patellar facet angle, the Wiberg angle, and the Wiberg index were measured and compared. RESULTS: In trochlear dysplasia knees, the mean patellar width and thickness and the lateral patellar facet angle were significantly smaller; the mean Wiberg index was significantly larger than in normal knees, regardless of gender (P < 0.05); and there was no statistically significant difference in the mean Wiberg angle (P > 0.05). In the female groups, the mean patellar width and thickness and the Wiberg angle were significantly smaller; the mean lateral patellar facet angle was significantly larger than those in the male groups (P < 0.05); and there was no significant difference in the mean Wiberg index (P > 0.05). In the low-grade dysplasia group, the mean Wiberg index was smaller than that in the high-grade dysplasia group (P < 0.05), regardless of gender; however, there was no significant difference in the mean patellar width and thickness, the lateral patellar facet angle, and the Wiberg angle in low-grade and high-grade dysplasia (P > 0.05). CONCLUSION: On CT scans, the patella in trochlear dysplasia had a smaller width, a thinner thickness, a lengthened lateral facet, and a more flattened articular facet. In addition, the patellar articular facet was more prominent in female patients. With the severity of trochlear dysplasia increased, the lateral patellar facet became longer. In addition, the abnormal stress distribution on the patella influenced the patellar morphology in trochlear dysaplasia.


Subject(s)
Bone Diseases, Developmental/diagnostic imaging , Patella/abnormalities , Patella/diagnostic imaging , Patellofemoral Joint/abnormalities , Patellofemoral Joint/diagnostic imaging , Adult , Female , Humans , Male , Sex Factors , Tomography, X-Ray Computed , Young Adult
15.
Front Microbiol ; 12: 816161, 2021.
Article in English | MEDLINE | ID: mdl-35281308

ABSTRACT

Vulvovaginal candidiasis (VVC) is considered the second most common cause of vaginitis after bacterial vaginosis and the most common lower genital tract infection during pregnancy. Candida albicans (C. albicans), an opportunistic pathogen, is the major species causing VVC. Recently, increasing researches have shown that lower reproductive tract infection during pregnancy can lead to various adverse pregnancy outcomes. However, the underlying mechanisms are not fully understood. Hence, we successfully established a mouse model of vaginal C. albicans infection and characterized the adverse pregnancy outcomes. C. albicans infection strikingly increased abortion rate and decreased litter size. Further analysis of placental development demonstrated that placental structure was abnormal, including that the area of spongiotrophoblast (Spo) and labyrinth (Lab) was reduced, and the formation of placental vessel was decreased in Lab zone. Accordingly, the expression of marker genes during placental development was downregulated. Collectively, the above findings revealed that vaginal C. albicans infection during pregnancy can inhibit placental development and ultimately lead to adverse pregnancy outcomes. This study enhances our comprehension of the effect of VVC on pregnancy, and placental dysplasia as a feasible orientation to explore VVC during pregnancy.

16.
J Clin Microbiol ; 59(2)2021 01 21.
Article in English | MEDLINE | ID: mdl-33148709

ABSTRACT

Bacterial vaginosis (BV) is caused by the excessive and imbalanced growth of bacteria in vagina, affecting 30 to 50% of women. Gram staining followed by Nugent scoring based on bacterial morphotypes under the microscope is considered the gold standard for BV diagnosis; this method is often labor-intensive and time-consuming, and results vary from person to person. We developed and optimized a convolutional neural network (CNN) model and evaluated its ability to automatically identify and classify three categories of Nugent scores from microscope images. The CNN model was first established with a panel of microscopic images with Nugent scores determined by experts. The model was trained by minimizing the cross-entropy loss function and optimized by using a momentum optimizer. The separate test sets of images collected from three hospitals were evaluated by the CNN model. The CNN model consisted of 25 convolutional layers, 2 pooling layers, and a fully connected layer. The model obtained 82.4% sensitivity and 96.6% specificity with the 5,815 validation images when altered vaginal flora and BV were considered the positive samples, which was better than the rates achieved by top-level technologists and obstetricians in China. The capability of our model for generalization was so strong that it exhibited 75.1% accuracy in three categories of Nugent scores on the independent test set of 1,082 images, which was 6.6% higher than the average of three technologists, who are hold bachelor's degrees in medicine and are qualified to make diagnostic decisions. When three technologists ran one specimen in triplicate, the precision of three categories of Nugent scores was 54.0%. One hundred three samples diagnosed by two technologists on different days showed a repeatability of 90.3%. The CNN model outperformed human health care practitioners in terms of accuracy and stability for three categories of Nugent score diagnosis. The deep learning model may offer translational applications in automating diagnosis of bacterial vaginosis with proper supporting hardware.


Subject(s)
Vaginosis, Bacterial , Bacteria , China , Female , Humans , Neural Networks, Computer , Vagina , Vaginosis, Bacterial/diagnosis
17.
J Environ Sci (China) ; 95: 266-277, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32653189

ABSTRACT

Biogenic volatile organic compounds (BVOCs) in the atmosphere play important roles in the formation of ground-level ozone and secondary organic aerosol (SOA) in global scale and also in regional scale under some condition due to their large amount and relatively higher reactivity. In places with high plant cover in the tropics and in China where air pollution is serious, the effect of BVOCs on ozone and secondary organic aerosols is strong. The present research aims to provide a comprehensive review about the emission rate, emission inventory, research methods, the influencing factors of BVOCs emissions, as well as their impacts on atmospheric environment quality and human health in recent years in Asia based on the summary and analysis of literatures. It is suggested to use field direct measurement method to obtain the emission rate and model method to calculate the emission amount. Several recommendations are given for future investigation and policy development on BVOCs emission.


Subject(s)
Air Pollutants/analysis , Air Pollution , Volatile Organic Compounds/analysis , Asia , China , Humans
18.
J Environ Sci (China) ; 95: 73-81, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32653195

ABSTRACT

Biogenic volatile organic compounds (BVOCs) have significant effects on atmospheric chemistry, ozone formation and secondary organic aerosol formation. Considering few investigations about BOVCs emissions in north China where is facing serious air pollution in recent years, emissions of various BVOCs from 24 dominant forest species in Beijing were measured from June to September in 2018, using a dynamic headspace sampling method. More than one hundred BVOCs in the collected samples were identified by using an automatic thermal desorption-gas chromatography/mass spectrometry, and their emission rates based on leaf biomass were calculated. Isoprene and monoterpenes were verified to be the dominant BVOCs emitted from the tree species, accounting for more than 50% of the total BVOCs. Generally, broad-leaved species displayed high isoprene emission rates, especially the Platanus occidentalis (21.36 µg/(g⋅hr)), Robinia pseudoacacia (11.55 µg/(g⋅hr)), and Lonicera maackii (9.17 µg/(g⋅hr)), while coniferous species emitted high rates of monoterpenes, such as Platycladus orientalis (27.18 µg/(g⋅hr)), Pinus griffithii (23.11 µg/(g⋅hr)), and Pinus armandii (7.42 µg/(g⋅hr)). High emission rates of monoterpenes from the broad-leaved species of Buxus megistophylla (13.07 µg/(g⋅hr)) and Ligustrum vicaryi (5.74 µg/(g⋅hr)), and high isoprene emission rate from the coniferous tree of Taxus cuspidata (5.86 µg/(g⋅hr)) were also observed. The emission rates of sesquiterpenes from each tree were usually 10-100 times smaller than those of isoprene and monoterpenes. Additionally, relatively high emission rates of oxygenated volatile organic compounds and other alkenes than isoprene and monoterpenes were also found for several tree species.


Subject(s)
Air Pollutants/analysis , Volatile Organic Compounds/analysis , Beijing , China , Forests
19.
Mycopathologia ; 185(3): 425-438, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32185617

ABSTRACT

PURPOSES: To investigate the role of 17ß-estrogen in Candida albicans (C. albicans) adhesion on human vaginal epithelial cells in vulvovaginal candidiasis (VVC). METHODS: The vaginal epithelial cell line, VK2/E6E7, was used to study the estrogen-induced molecular events between C. albicans and cells. An adhesion study was performed to evaluate the involvement of the estrogen-dependent focal adhesion kinase (FAK) activation in cell adhesion. The phosphorylation status of FAK and estrogen receptor α (ERα) upon estrogen challenge was assessed by western blotting. Specific inhibitors for ERα were used to validate the involvement of ERα-FAK signaling cascade. RESULTS: A transient activation of ERα and FAK was observed following the stimulation with 1000 nM estrogen for 48 h, as well as the increased average number of C. albicans adhering to each vaginal epithelial cell. Estrogen-induced activation of ERa and FAK was inhibited by the specific inhibitor of ERα, especially when the inhibitor reached a 10 µM concentration and allowed to act for 12 h. Simultaneously, a decrease in the number of adherent C. albicans was observed. However, this inhibitory effect diminished as the concentration of estrogen increased. CONCLUSION: FAK and ERα signaling cascades were involved in the early interaction between the vaginal epithelial cells and C. albicans, which appeared to be linked with the enhanced cell adhesion leading to VVC and promoted by a certain concentration of estrogen.


Subject(s)
Candida albicans/metabolism , Candidiasis, Vulvovaginal/microbiology , Estrogens/physiology , Focal Adhesion Kinase 2/metabolism , Vagina/cytology , Adhesiveness/drug effects , Blotting, Western , Candida albicans/drug effects , Candida albicans/physiology , Candidiasis, Vulvovaginal/pathology , Cell Line , Epithelial Cells/cytology , Epithelial Cells/microbiology , Estrogen Receptor Antagonists/pharmacology , Estrogen Receptor alpha/metabolism , Estrogens/administration & dosage , Female , Fulvestrant/pharmacology , Humans , Phosphorylation , Time Factors , Vagina/microbiology
20.
Sci Total Environ ; 696: 133974, 2019 Dec 15.
Article in English | MEDLINE | ID: mdl-31470317

ABSTRACT

Human exposure to fine particulate matter (PM2.5) in various environment could lead to a number of adverse health effects. Little is known about the toxic mechanism and the further response caused by PM2.5 exposure. In this study, a metabolomics approach using gas chromatography-mass spectrometry (GC-MS) was adopted to evaluate the liver toxicity induced by different gradient concentrations of PM2.5. A multivariate statistical analysis had shown, a total of 12 endogenous metabolites including amino acids and organic acids were identified as potential biomarkers of PM2.5 and most of them were down-regulated. By analyzing the metabolic pathways using the identified biomarkers, the significantly interfered metabolic pathways when mice were exposed to PM2.5 were found as: glycine, serine and threonine metabolism, aminoacyl-tRNA biosynthesis, cysteine and methionine metabolism, alanine, aspartate and glutamate metabolism, methane metabolism, linoleic acid metabolism and valine, and leucine and isoleucine biosynthesis, all of which were closely related to liver metabolism. The findings of this study reveal detailed toxic metabolic effects of PM2.5 in liver tissues, provide ways for assessing the health risk of PM2.5 at molecular level, and further offer insights on the potential mechanism of its toxicity.


Subject(s)
Air Pollutants/toxicity , Metabolome/drug effects , Particulate Matter/toxicity , Animals , Biomarkers , Lipid Metabolism , Liver/metabolism , Metabolic Networks and Pathways , Metabolomics , Mice
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