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1.
Small ; 20(11): e2306569, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38095443

ABSTRACT

The use of 2D materials to produce hydrogen (H2 ) fuel via photocatalytic water splitting has been intensively studied. However, the simultaneous fulfillment of the three essential requirements-high photon utilization, rapid carrier transfer, and low-barrier redox reactions-for wide-pH-range production of H2 still poses a significant challenge with no additional modulation. By employing the first-principles calculations, it has been observed that the Janus ZnXY2 structures (X = Si/Ge/Sn, Y = S/Se/Te) exhibit significantly enhanced built-in electric fields (0.20-0.36 eV Å-1 ), which address the limitations intrinsically. Compared to conventional Janus membranes, the ductile ZnSnSe2 and ZnSnTe2 monolayers have stronger regulation of electric fields, resulting in improved electron mobility and excitonic nature (Ebinding = 0.50/0.35 eV). Both monolayers exhibit lower energy barriers of hydrogen evolution reaction (HER, 0.98/0.86 eV, pH = 7) and resistance to photocorrosion across pH 0-7. Furthermore, the 1% tensile strain can further boost visible light utilization and intermediate absorption. The optimal AC-type bilayer stacking configuration is conducive to enhancing electric fields for photocatalysis. Overall, Janus ZnXY2 membranes overcome the major challenges faced by conventional 2D photocatalysts via intrinsic polarization and external amelioration, enabling efficient and controllable photocatalysis without the need for doping or heterojunctions.

5.
J Med Virol ; 88(6): 954-60, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26547266

ABSTRACT

Noroviruses (NoVs) are the most common cause of acute gastroenteritis in both sporadic and outbreak cases. Genotyping and recombination analyses were performed in order to help getting more knowledge of the distribution and genetic diversity of NoVs in Suzhou, located in Jiangsu province of China. All stool samples were collected from hospitalized children younger than 5 years old with acute gastroenteritis. For genotyping, the open reading frame (ORF) 1 and ORF2 were partially amplified and sequenced. 26.9% of stool samples were positive for genogroup II NoVs. The most common genotype was GII.4 and its variants included Den Haag-2006b, New Orleans-2009, and Sydney-2012. The Den Haag-2006b variants predominated during 2010-2012. In 2013, it was replaced by the Sydney-2012 variant. The second most common genotype was GII.12/GII.3. NoVs could be detected throughout the year, with GII.4 and GII.12/GII.3 coexisting during the cold months, and GII.4 was the main genotype during the warm months. The highest prevalence of NoV was detected in young children aged <24 months. Patients infected with GII.4 had a higher chance of getting moderate fever than other NoV-positive patients, while those infected with GII.12/GII.3 tended to have a mild degree of fever. NoV is an important pathogen responsible for viral gastroenteritis among children in Suzhou. Analyses of NoV circulating between 2010 and 2013 revealed a change of predominant variant of NoV GII.4 in each epidemic season and intergenotype recombinant strains represented an important part.


Subject(s)
Caliciviridae Infections/epidemiology , Caliciviridae Infections/virology , Gastroenteritis/virology , Norovirus/genetics , Acute Disease , Capsid Proteins/genetics , Child, Preschool , China/epidemiology , Epidemics , Epidemiological Monitoring , Feces/virology , Female , Fever/virology , Genetic Variation , Genotype , Hospitalization , Humans , Infant , Infant, Newborn , Male , Norovirus/classification , Norovirus/pathogenicity , Phylogeny , Prevalence , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction , Seasons , Sequence Analysis, DNA
6.
J Int Med Res ; 52(4): 3000605241239469, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38603615

ABSTRACT

Hepatic portal venous gas is often referred to as the "sign of death" because it signifies a very poor prognosis if appropriate treatments are not promptly administered. The etiologies of hepatic portal venous gas are diverse and include severe complex abdominal infections, mesenteric ischemia, diving, and complications of endoscopic surgery, and the clinical manifestations are inconsistent among individual patients. Thus, whether emergency surgery should be performed remains controversial. In this report, we present three cases of hepatic portal venous gas. The patients initially exhibited symptoms consistent with severe shock of unknown etiology and were treated in the intensive care unit upon admission. We rapidly identified the cause of each individual patient's condition and selected problem-directed intervention measures based on active organ support, antishock support, and anti-infection treatments. Two patients recovered and were discharged without sequelae, whereas one patient died of refractory infection and multiple organ failure. We hope that this report will serve as a valuable reference for decision-making when critical care physicians encounter similar patients.


Subject(s)
Portal Vein , Shock , Humans , Portal Vein/diagnostic imaging , Tomography, X-Ray Computed , Multiple Organ Failure/etiology , Intensive Care Units
7.
Nat Commun ; 15(1): 4701, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38830882

ABSTRACT

Immune checkpoint blockade (ICB) therapies function by alleviating immunosuppression on tumor-infiltrating lymphocytes (TILs) but are often insufficient to fully reactivate these dysfunctional TILs. Although interleukin 12 (IL-12) has been used in combination with ICB to improve efficacy, this remains limited by severe toxicity associated with systemic administration of this cytokine. Here, we engineer a fusion protein composed of an anti-PD-1 antibody and a mouse low-affinity IL-12 mutant-2 (αPD1-mIL12mut2). Systemic administration of αPD1-mIL12mut2 displays robust antitumor activities with undetectable toxicity. Mechanistically, αPD1-mIL12mut2 preferentially activates tumor-infiltrating PD-1+CD8+T cells via high-affinity αPD-1 mediated cis-binding of low-affinity IL-12. Additionally, αPD1-mIL12mut2 treatment exerts an abscopal effect to suppress distal tumors, as well as metastasis. Collectively, αPD1-mIL12mut2 treatment induces robust systemic antitumor responses with reduced side effects.


Subject(s)
CD8-Positive T-Lymphocytes , Interleukin-12 , Lymphocytes, Tumor-Infiltrating , Programmed Cell Death 1 Receptor , Animals , Interleukin-12/metabolism , Interleukin-12/immunology , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/drug effects , Programmed Cell Death 1 Receptor/metabolism , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Programmed Cell Death 1 Receptor/immunology , Mice , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/drug effects , Mice, Inbred C57BL , Cell Line, Tumor , Female , Immune Checkpoint Inhibitors/pharmacology , Humans , Recombinant Fusion Proteins/administration & dosage , Recombinant Fusion Proteins/genetics
8.
Yao Xue Xue Bao ; 48(12): 1743-54, 2013 Dec.
Article in Zh | MEDLINE | ID: mdl-24689230

ABSTRACT

Many studies have shown that chronic inflammation occurs in the brain of patients with Alzheimer's disease (AD). It is well known that long-term administration of non-steroidal anti-inflammatory drugs (NSAIDs) can alleviate the cognitive decline of AD patient and elderly. Several inflammatory cytokines produced in the metabolism of arachidonic acid (AA) are closely related to inflammatory diseases. Lipoxygenases (LOXs) and cyclooxygenases (COXs) play a crucial role in the AA network, the products eicosanoids have an important impact on the progression of AD. Although there are many arguments and conflicting evidence, currently LOXs and COXs are still the hot topics in the research on AD pathogenesis and drug development. Here, we review the progress in research on COXs and LOXs, including their actions on CNS and their association with AD, and explore the feasibility of LOXs and COXs as targets for the drugs to prevent and/or treat AD.


Subject(s)
Alzheimer Disease/prevention & control , Anti-Inflammatory Agents, Non-Steroidal , Cyclooxygenase Inhibitors/therapeutic use , Lipoxygenase Inhibitors/therapeutic use , Lipoxygenases/metabolism , Prostaglandin-Endoperoxide Synthases/metabolism , Alzheimer Disease/drug therapy , Alzheimer Disease/enzymology , Amyloid beta-Peptides/metabolism , Animals , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Arachidonic Acid/metabolism , Brain/metabolism , Cyclooxygenase 1/metabolism , Cyclooxygenase 2/metabolism , Humans , Prostaglandin H2/metabolism
9.
Air Qual Atmos Health ; 16(4): 817-839, 2023.
Article in English | MEDLINE | ID: mdl-36819790

ABSTRACT

With continuous global warming, growing urban population density, and increasing compactness of urban buildings, the "void deck" street canyon design has become increasingly popular in city planning, especially for urban streets located in tropical areas. Nevertheless, research on traffic pollutant dispersion in street canyons with void decks (VDs) is still at its early stage. This study quantitatively evaluates the effects of void deck height and location on the canyon ventilation and pollutant dispersion in asymmetric street canyons with void decks, and the pollutant exposure risk level for pedestrians and street dwellers. Void decks introduce more fresh air, thereby greatly improving the ventilation properties of the asymmetric canyon. The air exchange rate (ACH: 147.9%, 270.9%) and net escape velocity (NEV*: 416.7%, 915.8%) of the step-up and step-down canyons with VDs (3 m high at full scale) at both buildings are higher than those of regular asymmetric canyons. Moreover, the mean dimensionless pollutant concentration (K) on the building wall and pedestrian respiration plane in which VDs are located stands at a low level, because pollutants are removed by the airflow entering or exiting through the void decks. Increased VD height (4.5 m at full scale) enhances the strength of airflow flowing into and out of the canyon, significantly increasing ACH (177.3%, 380.9%) and NEV* (595.2%, 1268.4%) and decreasing the mean K on both pedestrian respiration planes and canyon walls. In particular, the K values on both pedestrian respiration planes and both walls are almost zero for the canyons with VDs at both buildings. Therefore, among the three VD locations, both VDs provide the best living environment for pedestrians and near-road residents. These findings can help to design urban street canyons for mitigating traffic pollution risk and improving ventilation in tropical cities.

10.
Amino Acids ; 43(1): 97-109, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22367578

ABSTRACT

L-carnosine (ß-alanyl-L-histidine; CAR) is synthesized in mammalian skeletal muscle. Although the physiological roles of CAR have not yet been clarified, there is evidence that the release of CAR from skeletal muscle during physical exercise affects autonomic neurotransmission and physiological functions. In particular, CAR affects the activity of sympathetic and parasympathetic nerves innervating the adrenal glands, liver, kidney, pancreas, stomach, and white and brown adipose tissues, thereby causing changes in blood pressure, blood glucose, appetite, lipolysis, and thermogenesis. CAR-mediated changes in neurotransmission and physiological functions were eliminated by histamine H1 or H3 receptor antagonists (diphenhydramine or thioperamide) and bilateral lesions of the hypothalamic suprachiasmatic nucleus (SCN), a master circadian clock. Moreover, a carnosine-degrading enzyme (carnosinase 2) was shown to be localized to histamine neurons in the hypothalamic tuberomammillary nucleus (TMN). Thus, CAR released from skeletal muscle during exercise may be transported into TMN-histamine neurons and hydrolyzed. The resulting L-histidine may subsequently be converted into histamine, which could be responsible for the effects of CAR on neurotransmission and physiological function. Thus, CAR appears to influence hypoglycemic, hypotensive, and lipolytic activity through regulation of autonomic nerves and with the involvement of the SCN and histamine. These findings are reviewed and discussed in the context of other recent reports, including those on carnosine synthetases, carnosinases, and carnosine transport.


Subject(s)
Autonomic Pathways/metabolism , Blood Glucose/metabolism , Blood Pressure , Carnosine/metabolism , Circadian Clocks/physiology , Histamine/metabolism , Lipolysis , Thermogenesis , Animals , Dipeptidases/metabolism , Diphenhydramine/pharmacology , Histamine H1 Antagonists/pharmacology , Histamine H3 Antagonists/pharmacology , Piperidines/pharmacology , Rats , Suprachiasmatic Nucleus/injuries , Suprachiasmatic Nucleus/pathology
11.
J Exp Med ; 219(12)2022 12 05.
Article in English | MEDLINE | ID: mdl-36165896

ABSTRACT

Checkpoint blockade immunotherapy releases the inhibition of tumor-infiltrating lymphocytes (TILs) but weakly induces TIL proliferation. Exogenous IL-15 could further expand TILs and thus synergize with αPD-L1 therapy. However, systemic delivery of IL-15 extensively expands peripheral NK cells, causing severe toxicity. To redirect IL-15 to intratumoral PD-1+CD8+T effector cells instead of NK cells for better tumor control and lower toxicity, we engineered an anti-PD-1 fusion with IL-15-IL-15Rα, whose activity was geographically concealed by immunoglobulin Fc region with an engineered linker (αPD-1-IL-15-R) to bypass systemic NK cells. Systematic administration of αPD-1-IL-15-R elicited extraordinary antitumor efficacy with undetectable toxicity. Mechanistically, cis-delivery of αPD-1-IL-15-R vastly expands tumor-specific CD8+T cells for tumor rejection. Additionally, αPD-1-IL-15-R upregulated PD-1 and IL-15Rß on T cells to create a feedforward activation loop, thus rejuvenating TILs, not only resulting in tumor control in situ, but also suppressing tumor metastasis. Collectively, renavigating IL-15 to tumor-specific PD-1+CD8+T cells, αPD-1-IL-15-R elicits effective systemic antitumor immunity.


Subject(s)
Interleukin-15 , Neoplasms , CD8-Positive T-Lymphocytes , Humans , Immune Checkpoint Inhibitors , Interleukin-15/pharmacology , Lymphocytes, Tumor-Infiltrating
12.
Curr Med Sci ; 42(5): 991-999, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36107305

ABSTRACT

OBJECTIVE: The main pathological feature of immunoglobulin A nephropathy (IgAN), an autoimmune kidney disease, is the deposition of IgA immune complexes, accompanied by mesangial cell proliferation and elevated urine protein. The Guben Tongluo formula (GTF) is a traditional Chinese medicine prescription, which has predominant protective effects on IgAN. However, the therapeutic mechanism of the GTF in IgAN remains elusive. The present study aimed to determine the effects of GTF in treating IgAN via regulating the TLR4/MyD88/NF-κB pathway. METHODS: In the present study, lamina propria B lymphocytes were treated with different concentrations of lipopolysaccharide (LPS) (0, 1, 5, 10 and 20 ng/mL). Flow cytometry was used to define positive CD86+CD19+ cells. CCK-8 assay was used to examine cell proliferation. RNAi was used to induce TLR4 silencing. qRT-PCR and Western blotting were used to determine gene expression. RESULTS: It was found that the LPS dose-dependently increased the content of IgA and galactose-deficient IgA1 (Gd-IgA), the levels of TLR4, Cosmc, MyD88 and phosphorylated (p)-NF-κB, and the ratio of CD86+CD19+ and IgA-producing B cells. However, the TLR4 knockdown reversed the role of LPS. This suggests that TLR4 mediates the effects of LPS on lamina propria B lymphocytes. Furthermore, the GTF could dose-dependently counteract the effects of LPS and TLR4 overexpression on lamina propria B lymphocytes through the TLR4/MyD88/NF-κB pathway. CONCLUSION: Collectively, these results demonstrate that the GTF can regulate the TLR4/MyD88/NF-κB pathway to treat IgAN model lamina propria B lymphocytes stimulated by LPS.


Subject(s)
Glomerulonephritis, IGA , NF-kappa B , Humans , NF-kappa B/metabolism , Lipopolysaccharides/adverse effects , Myeloid Differentiation Factor 88/genetics , Myeloid Differentiation Factor 88/metabolism , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism , Antigen-Antibody Complex/metabolism , Antigen-Antibody Complex/pharmacology , Antigen-Antibody Complex/therapeutic use , Galactose/pharmacology , Galactose/therapeutic use , Signal Transduction , B-Lymphocytes/metabolism , Immunoglobulin A/metabolism , Mucous Membrane/metabolism
13.
Chemosphere ; 286(Pt 1): 131586, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34303907

ABSTRACT

Monitoring of disinfection by-products (DBPs) in water supply system is important to ensure safety of drinking water. Yet it is a laborious job. Developing predictive DBPs models using simple and easy parameters is a promising way. Yet current models could not be well applied into practice because of the improper dataset (e.g. not from real tap water) they used or involving the parameters that are difficult to measure or require expensive instruments. In this study, four simple and easy water quality parameters (temperature, pH, UVA254 and Cl2) were used to predict trihalomethane (THMs) occurrence in tap water. Linear/log linear regression models (LRM) and radial basis function artificial neural network (RBF ANN) were adopted to develop the THMs models. 64 observations from tap water samples were used to develop and test models. Results showed that only one or two parameters entered LRMs, and their prediction ability was very limited (testing datasets: N25 = 46-69%, rp = 0.334-0.459). Different from LRM, the prediction accuracy of RBF ANNs developed with pH, temperature, UVA254 and Cl2 can be improved continuously by tweaking the maximum number of neuron (MN) and Gaussian function spread (S) until it reached best. The optimum RBF ANNs of T-THMs, TCM and BDCM were obtained when setting MN = 20, S = 100, 100.1 and 60, respectively, where the N25 and rp values for testing datasets reached 85-92% and 0.813-0.886, respectively. Accurate predictions of THMs by RBF ANNs with these four simple and easy parameters paved an economic and convenient way for THMs monitoring in real water supply system.


Subject(s)
Disinfectants , Drinking Water , Water Pollutants, Chemical , Water Purification , Disinfectants/analysis , Disinfection , Neural Networks, Computer , Trihalomethanes/analysis , Water Pollutants, Chemical/analysis , Water Quality , Water Supply
14.
Nat Cell Biol ; 24(12): 1754-1765, 2022 12.
Article in English | MEDLINE | ID: mdl-36474070

ABSTRACT

Immune checkpoint blockade (ICB)-based immunotherapy depends on functional tumour-infiltrating lymphocytes (TILs), but essential cytokines are less understood. Here we uncover an essential role of endogenous IL-2 for ICB responsiveness and the correlation between insufficient IL-2 signalling and T-cell exhaustion as tumours progress. To determine if exogenous IL-2 in the tumour microenvironment can overcome ICB resistance, we engineered mesenchymal stem cells (MSCs) to successfully deliver IL-2 mutein dimer (SIL2-EMSC) to TILs. While MSCs have been used to suppress inflammation, SIL2-EMSCs elicit anti-tumour immunity and overcome ICB resistance without toxicity. Mechanistically, SIL2-EMSCs activate and expand pre-existing CD8+ TILs, sufficient for tumour control and induction of systemic anti-tumour effects. Furthermore, engineered MSCs create synergy of innate and adaptive immunity. The therapeutic benefits of SIL2-EMSCs were also observed in humanized mouse models. Overall, engineered MSCs rejuvenate CD8+ TILs and thus potentiate ICB and chemotherapy.


Subject(s)
Mesenchymal Stem Cells , Neoplasms , Animals , Mice , CD8-Positive T-Lymphocytes , Interleukin-2/genetics , Interleukin-2/pharmacology , Neoplasms/therapy , Tumor Microenvironment
15.
Skin Res Technol ; 17(1): 75-81, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20923465

ABSTRACT

BACKGROUND/PURPOSE: We observed that olfactory stimulation with scent of grapefruit oil elevated the activities of sympathetic nerves, and increased the plasma glycerol concentration and blood pressure. In contrast, olfactory stimulation with scent of lavender oil had opposite effects in rats. These suggest that changes in autonomic activities cause physiological functions via histaminergic H1 and H3 receptor. Moreover, it has been reported that somatic sensory stimulation affected autonomic neurotransmission. To examine effects of skin application of urea-containing cream on cutaneous arterial sympathetic nerve activity (CASNA), blood flow, and transepidermal water loss (TEWL). METHOD: The activity of CASNA was determined by electrophysiological method, and cutaneous blood flow was determined using laser flowmeter in urethane-anesthetized rats, TEWL was measured using VapoMeter in the back skin of HWY hairless rats. RESULTS: CASNA was markedly and significantly inhibited by skin application of 10% urea-containing cream, whereas cutaneous blood flow was significantly elevated via histaminergic H3-receptor. In conscious hairless rats, TEWL was significantly decreased 24 h after application of 10% urea-containing cream to the back skin. CONCLUSION: These findings suggest that skin application of 10% urea-containing cream increases the cutaneous blood flow and water retaining ability, and that histaminergic H3-receptors may mediate these effects.


Subject(s)
Emollients/pharmacology , Regional Blood Flow/drug effects , Sympathetic Nervous System/drug effects , Urea/pharmacology , Water/metabolism , Administration, Topical , Anesthetics, Intravenous , Animals , Consciousness , Histamine Antagonists/pharmacology , Male , Maleates/pharmacology , Piperidines/pharmacology , Rats , Rats, Hairless , Rats, Wistar , Receptors, Histamine H3/metabolism , Skin/blood supply , Skin/innervation , Skin/metabolism , Sympathetic Nervous System/physiology , Urethane
16.
Cell Res ; 31(11): 1190-1198, 2021 11.
Article in English | MEDLINE | ID: mdl-34376814

ABSTRACT

IL-15 is a promising cytokine to expand NK and CD8+ T cells for cancer immunotherapy, but its application is limited by dose-limiting, on-target off-tumor toxicity. Here, we have developed a next-generation IL-15 that is activated inside the tumor microenvironment (TME). This pro-IL-15 has the extracellular domain of IL-15Rß fused to the N-terminus of sIL-15-Fc through a tumor-enriched Matrix Metalloproteinase (MMP) cleavable peptide linker to block its activity. Unlike sIL-15-Fc, pro-IL-15 does not activate the peripheral expansion of NK cells and T cells, thus reducing systemic toxicity, but it still preserves efficient anti-tumor abilities. In various mouse tumors, the anti-tumor effect of pro-IL-15 depends on intratumoral CD8+ T cells and IFN-γ. Pro-IL-15 increases the stem-like TCF1+Tim-3-CD8+ T cells within tumor tissue and helps overcome immune checkpoint blockade (ICB) resistance. Moreover, pro-IL-15 synergizes with current tyrosine kinase inhibitor (TKI) targeted-therapy in a poorly inflamed TUBO tumor model, suggesting that pro-IL-15 helps overcome targeted-therapy resistance. Our results demonstrate a next-generation IL-15 cytokine that can stimulate potent anti-tumor activity without severe toxicity.


Subject(s)
Interleukin-15 , Neoplasms , Animals , CD8-Positive T-Lymphocytes , Cytokines , Immunotherapy , Mice , Neoplasms/drug therapy , Tumor Microenvironment
17.
Sci Total Environ ; 772: 145534, 2021 Jun 10.
Article in English | MEDLINE | ID: mdl-33571763

ABSTRACT

Haloketones (HKs) is one class of disinfection by-products (DBPs) which is genetically toxic and mutagenic. Monitoring HKs in drinking water is important for drinking water safety, yet it is a time-consuming and laborious job. Developing predictive models of HKs to estimate their occurrence in drinking water is a good alternative, but to date no study was available for HKs modeling. This study was to explore the feasibility of linear, log linear regression models, back propagation (BP) as well as radial basis function (RBF) artificial neural networks (ANNs) for predicting HKs occurrence (including dichloropropanone, trichloropropanone and total HKs) in real water supply systems. Results showed that the overall prediction ability of RBF and BP ANNs was better than linear/log linear models. Though the BP ANN showed excellent prediction performance in internal validation (N25 = 98-100%, R2 = 0.99-1.00), it could not well predict HKs occurrence in external validation (N25 = 62-69%, R2 = 0.202-0.848). Prediction ability of RBF ANN in external validation (N25 = 85%, R2 = 0.692-0.909) was quite good, which was comparable to that in internal validation (N25 = 74-88%, R2 = 0.799-0.870). These results demonstrated RBF ANN could well recognized the complex nonlinear relationship between HKs occurrence and the related water quality, and paved a new way for HKs prediction and monitoring in practice.


Subject(s)
Neural Networks, Computer , Water , Disinfection
18.
PLoS Negl Trop Dis ; 15(4): e0009319, 2021 04.
Article in English | MEDLINE | ID: mdl-33861752

ABSTRACT

Trichomonas vaginalis is a common protozoan parasite, which causes trichomoniasis associated with severe adverse reproductive outcomes. However, the underlying pathogenesis has not been fully understood. As the first line of defense against invading pathogens, the vaginal epithelial cells are highly responsive to environmental stimuli and contribute to the formation of the optimal luminal fluid microenvironment. The cystic fibrosis transmembrane conductance regulator (CFTR), an anion channel widely distributed at the apical membrane of epithelial cells, plays a crucial role in mediating the secretion of Cl- and HCO3-. In this study, we investigated the effect of T. vaginalis on vaginal epithelial ion transport elicited by prostaglandin E2 (PGE2), a major prostaglandin in the semen. Luminal administration of PGE2 triggered a remarkable and sustained increase of short-circuit current (ISC) in rat vaginal epithelium, which was mainly due to Cl- and HCO3- secretion mediated by the cAMP-activated CFTR. However, T. vaginalis infection significantly abrogated the ISC response evoked by PGE2, indicating impaired transepithelial anion transport via CFTR. Using a primary cell culture system of rat vaginal epithelium and a human vaginal epithelial cell line, we demonstrated that the expression of CFTR was significantly down-regulated after T. vaginalis infection. In addition, defective Cl- transport function of CFTR was observed in T. vaginalis-infected cells by measuring intracellular Cl- signals. Conclusively, T. vaginalis restrained exogenous PGE2-induced anion secretion through down-regulation of CFTR in vaginal epithelium. These results provide novel insights into the intervention of reproductive complications associated with T. vaginalis infection such as infertility and disequilibrium in vaginal fluid microenvironment.


Subject(s)
Anions/metabolism , Chlorides/metabolism , Trichomonas Vaginitis/drug therapy , Vagina/pathology , Animals , Anions/pharmacology , Biological Transport , Cell Line , Cells, Cultured , Chloride-Bicarbonate Antiporters/physiology , Cyclic AMP/metabolism , Cystic Fibrosis Transmembrane Conductance Regulator/metabolism , Dinoprostone/metabolism , Epithelial Cells/drug effects , Epithelium/metabolism , Epithelium/parasitology , Epithelium/pathology , Female , Humans , Rats , Rats, Sprague-Dawley , Trichomonas Vaginitis/parasitology , Trichomonas vaginalis/metabolism , Vagina/metabolism , Vagina/parasitology
19.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 41(1): 148-52, 2010 Jan.
Article in Zh | MEDLINE | ID: mdl-20369492

ABSTRACT

OBJECTIVE: To determine residues of multiple biphenyl ether herbicides simultaneously in water using high performance liquid chromatography (HPLC) with cloud-point extraction. METHODS: The residues of eight biphenyl ether herbicides (including bentazone, fomesafen, acifluorfen, aclonifen, bifenox, fluoroglycofenethy, nitrofen, oxyfluorfen) in water samples were extracted with cloud-point extraction of Triton X-114. The analytes were separated and determined using reverse phase HPLC with ultraviolet detector at 300 nm. Optimized conditions for the pretreatment of water samples and the parameters of chromatographic separation applied. RESULTS: There was a good linear correlation between the concentration and the peak area of the analytes in the range of 0.05-2.00 mg/L (r = 0.9991-0.9998). Except bentazone, the spiked recoveries of the biphenyl ether herbicides in the water samples ranged from 80.1% to 100.9%, with relative standard deviations ranging from 2.70% to 6.40%. The detection limit of the method ranged from 0.10 microg/L to 0.50 microg/L. CONCLUSION: The proposed method is simple, rapid and sensitive, and can meet the requirements of determination of multiple biphenyl ether herbicides simultaneously in natural waters.


Subject(s)
Biphenyl Compounds/analysis , Chromatography, High Pressure Liquid/methods , Herbicides/analysis , Pesticide Residues/analysis , Water Pollutants, Chemical/analysis , Benzamides/analysis , Benzothiadiazines/analysis , Nitrobenzoates/analysis , Sensitivity and Specificity
20.
Neuropeptides ; 43(1): 21-9, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18996592

ABSTRACT

Previous studies have demonstrated that neuropeptide Y (NPY) affects blood pressure (BP) in anesthetized rats. Here, we examined the effects of the third cerebral ventricular (3CV) injection of various doses of NPY on renal sympathetic nerve activity (RSNA) and BP in anesthetized rats. 3CV injection of NPY suppressed RSNA and BP in a dose-dependent manner. Moreover, suppressing effects of NPY on RSNA and BP were eliminated by lateral cerebral ventricular (LCV) preinjection of thioperamide, an antagonist of histaminergic H3-receptor, not diphenhydramine, an antagonist of histaminergic H1-receptor. In addition, 3CV injection of NPY accelerated gastric vagal nerve activity (GVNA) and inhibited brown adipose tissue sympathetic nerve activity (BAT-SNA) of anesthetized rats, and lowered brown adipose tissue temperature (BAT-T) of conscious rats. Thus, these evidences suggest that central NPY affects autonomic nerves containing RSNA, GVNA or BAT-SNA, and BP by mediating central histaminergic H3-receptors.


Subject(s)
Adrenergic Fibers/drug effects , Blood Pressure/drug effects , Heart Rate/drug effects , Neuropeptide Y/pharmacology , Adipose Tissue, Brown/drug effects , Adipose Tissue, Brown/metabolism , Adrenergic Fibers/metabolism , Animals , Blood Pressure/physiology , Diphenhydramine/metabolism , Diphenhydramine/pharmacology , Dose-Response Relationship, Drug , Histamine H1 Antagonists/metabolism , Histamine H1 Antagonists/pharmacology , Histamine H3 Antagonists/metabolism , Histamine H3 Antagonists/pharmacology , Injections, Intraventricular , Male , Neuropeptide Y/metabolism , Piperidines/metabolism , Piperidines/pharmacology , Rats , Rats, Wistar , Telemetry
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