Application of environmental DNA metabarcoding to identify fish community characteristics in subtropical river systems.

Fish are vital in river ecosystems; however, traditional investigations of fish usually cause ecological damage. Extracting DNA from aquatic environments and identifying DNA sequences offer an alternative, noninvasive approach for detecting fish species. In this study, the effects of environmental DNA (eDNA), coupled with PCR and next-generation sequencing, and electrofishing for identifying fish community composition and diversity were compared. In three subtropical rivers of southern China, fish specimens and eDNA in water were collected along the longitudinal (upstream-downstream) gradient of the rivers. Both fish population parameters, including species abundance and biomass, and eDNA OTU richness grouped 38 sampling sites into eight spatial zones with significant differences in local fish community composition. Compared with order-/family-level grouping, genus-/species-level grouping could more accurately reveal the differences between upstream zones I-III, midstream zones IV-V, and downstream zones VI-VIII. From the headwaters to the estuary, two environmental gradients significantly influenced the longitudinal distribution of the fish species, including the first gradient composed of habitat and physical water parameters and the second gradient composed of chemical water parameters. The high regression coefficient of alpha diversity between eDNA and electrofishing methods as well as the accurate identification of dominant, alien, and biomarker species in each spatial zone indicated that eDNA could characterize fish community attributes at a level similar to that of traditional approaches. Overall, our results demonstrated that eDNA metabarcoding can be used as an effective tool for revealing fish composition and diversity, which is important for using the eDNA technique in aquatic field monitoring.

Hydrology and water quality shape macroinvertebrate patterns and facilitate non-native species dispersals in an inter-basin water transfer system.

Understanding biotic assemblage variations resulting from water diversions and other pressures is critical for aquatic ecosystem conservation, but hampered by limited research. Mechanisms driving macroinvertebrate assemblages were determined across five lakes along China's South-to-North Water Diversion Project, an over 900-km water transfer system connecting four river basins. We assessed macroinvertebrate patterns from 59 sites in relation to water quality, climatic, spatial, and hydrologic factors. Macroinvertebrate density, biomass, and species richness increased from upriver to downriver lakes, and were higher during the water transfer period than in the non-water transfer period. Non-native species including Nephtys sp., Paranthura japonica, Potamillacf acuminata, Capitekkidae spp. and Novaculina chinensis, were distributed along the entire study system, some become dominant in upriver lakes. High species turnover occurred in two upriver lakes. Hydrology and water quality are critical factors in shaping these macroinvertebrate patterns. Hydrological disturbance by water transfer boosted macroinvertebrate abundance during the water transfer period while facilitated non-native species dispersals and increased biotic homogenization. This study indicates the need for: 1) an effective ecosystem monitoring system; 2) unified system management standards; 3) external pollution controls; and 4) limiting the dispersal of non-native species.

Climate, hydrology, and human disturbance drive long-term (1988-2018) macrophyte patterns in water diversion lakes.

Macrophytes are affected by many natural and human stressors globally but their long-term responses to these multiple stressors are not often quantified. We employed remote sensing and statistical tools to analyze datasets from both short-term (2017-2018) field investigations to explore seasonal patterns, and long-term (1988-2018) Landsat remote-sensing images to detect annual patterns of macrophyte distributions and study their responses to changes in climate, hydrology, and anthropogenic activities in a chain of water diversion lakes in eastern China. We found: 1) biomass and species richness of macrophytes peaked in summer with dominant species of submerged macrophytes Ceratophyllum demersum, Potamogeton pectinatus, and Potamogeton maackianus and floating macrophytes Trapa bispinosa, and non-native species Cabomba caroliniana spread in midstream Luoma Lake and Nansi Lake in summer, while Potamogeton crispus was dominant in all the lakes in spring; 2) water physicochemical parameters (chloride and water depth), lake characteristics (area and water storage), climate factors (air temperature and precipitation), and anthropogenic activities (commercial fishery and urban development) were significantly correlated to the seasonal distribution of macrophytes; 3) long-term data showed a significantly negative correlation between coverage of floating macrophytes and precipitation where the wettest year of 2003 had the lowest coverage of floating macrophytes; and 4) climate (air temperature) and hydrology (water level) were positively correlated with total macrophyte coverage, but human disturbance indexed by the gross domestic product was negatively driving long-term coverage of macrophytes. Our study has important implications for understanding the long-term succession of macrophytes under both natural and human stressors, and for future environmental management and ecological restoration of freshwater lakes.

Spatial and temporal patterns of heavy metals and potential human impacts in Central Yangtze lakes, China.

Lakes in the central Yangtze River basin have experienced increasing levels of human disturbance during the past several decades, yet large-scale environmental patterns in these lakes and their driving factors remain unclear. Herein we examined spatial and temporal patterns of copper (Cu), zinc (Zn), lead (Pb), arsenic (As), and seven other heavy metals from 16 lakes experiencing a gradient of human disturbance. These lakes were divided among six groups: suburban reservoirs (SR), suburban high-aquaculture lakes (SH), suburban low-aquaculture lakes (SL), suburban no-aquaculture lakes (SN), urban aquaculture lakes (UA) and urban no-aquaculture lakes (UN). Spatially, water-column concentrations of Cd, Ni, Co, Mn, Fe, and Al, and sediment concentrations of Ni were significantly lower in SR compared to other lake groups. Except for Al, heavy metal concentrations did not differ between SN and SL lakes in the water-column or sediments. SH lakes exhibited significantly greater concentrations of Cu, Co, Cr, Mn, and Al in the water-column and Zn in sediments compared to SN lakes. UA lakes contained significantly lower concentrations of Zn, Cd, and Al in sediment compared to UN lakes, though no significant differences were detected within water-column samples. Temporally, with all lake groups combined, summer water-column concentrations of Cd, Pb, Co, Mn, and Al were lower compared to spring and autumn. Additionally, summer sediment concentrations of Zn, As, Co, Fe also were lower compared to autumn. Further results indicated that low-density fish stockings without external feed inputs appeared to have little impact on heavy metals in both suburban and urban lakes. However, high-density fish stockings with external feed inputs were associated with increased heavy-metal concentrations across all lakes. Overall, urbanization has great potential to increase sediment heavy-metal ecological risks. These findings are crucial for developing heavy-metal pollution control and management strategies for freshwater lakes.

Longitudinal pattern of resource utilization by aquatic consumers along a disturbed subtropical urban river: Estimating the relative contribution of resources with stable isotope analysis.

The utilization of food resources by aquatic consumers reflects the structure and functioning of river food webs. In lotic water systems, where food availability and predator-prey relationships vary with gradient changes in physical conditions, understanding diet assimilation by local communities is important for ecosystem conservation. In the subtropical Liuxi River, southern China, the relative contribution of basal resources to the diet assimilation of functional feeding groups (FFGs) was determined by stable carbon (13C) and nitrogen (15N) isotope analyses. The output of Bayesian mixing models showed that diatom-dominated periphyton (epilithic biofilm), aquatic C3 plants (submerged hydrophytes), and suspended particulate organic matter (SPOM) associated with terrestrial C3 plants contributed the most to the diet assimilation of FFGs in the upper, middle, and lower reaches, respectively. The relative contribution of consumer diet assimilation was weighted by the biomass (wet weight, g/m2) of each FFG to reflect resource utilization at the assemblage level. From the upper to the lower reaches, the spatial variation in the diet assimilation of fish and invertebrate assemblages could be summarized as a longitudinal decrease in periphyton (from 57%-76% to <3%) and an increase in SPOM (from <7% to 51%-68%) with a notable midstream increase in aquatic C3 plants (23%-48%). These results indicate that instream consumers in the Liuxi River rely more on autochthonous production (e.g., periphyton and submerged hydrophytes) than on terrestrially derived allochthonous matter (e.g., terrestrial plants). The pattern of resource utilization by consumers in the mid-upper Liuxi River is consistent with findings from other open subtropical and neotropical rivers and provides evidence for the riverine productivity model. Our study indicates that protecting inherent producers in rivers (e.g., periphyton and submerged hydrophytes) and restoring their associated habitats (e.g., riffles with cobble substrate) are conducive to aquatic ecosystem management.

A holistic assessment of water quality condition and spatiotemporal patterns in impounded lakes along the eastern route of China's South-to-North water diversion project.

Water quality is one of the key determinants for assessing effectiveness and success of water diversions, but rarely studied at a spatial scale that crosses large river basins. Multiple statistical methods and the water quality index (WQI) were used to assess overall condition and detect spatiotemporal patterns of water quality in a series of impounded lakes along the Eastern Route of China's South-to-North Water Diversion Project. Principal components analysis and analysis of variances identified three groups with distinct water quality characteristics: upstream Gaoyou Lake and Hongze Lake showing relatively higher nutrients, turbidity, and total suspended solids; downstream Dongping lake and Donghu Lake showing higher conductivity, total hardness, and chloride; and Luoma Lake and Nansi Lake intermediate between the two former groups. The WQI indicated overall "Good" water quality with an improving trend from upstream to downstream lakes. The upstream Gaoyou Lake had over 55% of the monitoring sites with "Moderate" water quality in all the seasons. Management should focus on preventing high nitrogen, phosphorus, turbidity, and total suspended solids in upstream lakes, high chloride in downstream lakes, high nitrogen during water diversion seasons, and high phosphorus during non-water diversion seasons. These findings greatly improved our understanding of the spatiotemporal water quality patterns of the impounded lakes, and can be used to develop water quality management strategies. This study exemplifies a methodology for investigating and securing water quality for inter-basin water transfer projects.

Patterns of fish communities and water quality in impounded lakes of China's south-to-north water diversion project.

Understanding the ecological impacts of large-scale hydraulic projects is critical for maintaining ecosystem health while meeting human water needs. It is, however, currently hindered by a lack of direct evidence on ecological impacts associated with this type of project particularly on water quality and fish communities. Here, we characterized patterns and variations of fish communities and water quality in five impounded lakes of the Chinese South-to-North Water Diversion Project (SNWDP), with the aim of better understanding potential ecological impacts of inter-basin water transfers. We found that 1) the impacts of water transfer on water quality in the impounded lakes was generally characterized by hydrological parameters (e.g. total suspended solids, turbidity, transparency, chlorophyll a, dissolved oxygen, conductivity and total hardness) in an upstream-downstream direction; 2) increased hydrological connectivity may have favored biological invasion (e.g. Tridentiger bifasciatus) and promoted a potential biotic homogenization among the impounded lakes; and 3) there was a pattern of decreased fish abundance and biomass from the upstream to downstream lakes with fish communities strongly driven by changing water quality patterns across the impounded lakes. These findings improve our understanding of ecological impacts of large-scale hydraulic projects and provide a significant basis for water agencies with similar water transfer systems to optimize their water transfer management in order to minimize ecological impacts.

Eutrophication and heavy metal pollution patterns in the water suppling lakes of China's south-to-north water diversion project.

This study used non-supervised machine learning self-organizing maps (SOM) in conjunction with traditional multivariate statistical techniques (e.g., hierarchical cluster analysis, principle component analysis, Pearson's correlation analysis) to investigate spatio-temporal patterns of eutrophication and heavy metal pollution in the water supplying lakes (i.e., the Gao-Bao-Shaobo Lake, GBSL) of the eastern route of China's South-to-North Water Diversion Project (SNWDP-ER). A total of 28 water quality parameters were seasonally monitored at 33 sampling sites in the GBSL during 2016 to 2017 (i.e., 132 water samples were collected in four seasons). The results indicated that: 1) spatially, the western and south-western GBSL was relatively more eutrophic and polluted with heavy metals; and 2) temporally, the lakes suffered from high risks of heavy metal contamination in spring, but eutrophication in summer while water quality in winter was the best among the four seasons. Two main potential sources of pollution and transport routes were identified and discussed based on the pollution patterns. These findings contributed considerably to providing in-depth understanding of water pollution patterns, as well as potential pollution sources in the water-supplying region. Such understanding is crucial for developing pollution control and management strategies for this mega inter-basin water transfer project.

[Inhibition effect on Microcystis aeruginosa PCC7806 as well as separation and identification of algicidal substances isolated from Salvinia natans (L.) All].

OBJECTIVE: To study the inhibition effect of Salvinia natans ( L. ) All. on harmful algae. METHODS: With Microcystis aeruginosa as the subjects, deionized water, ethanol, acetone, ethyl acetate as solvent, four kinds of crude extracts from Salvinia natans (L.) All. were prepared, and their alga-inhibiting actions were verified, respectively. The crude extracts of Salvinia natans (L.) All. with better inhibition effect were selected. The components of algal inhibiting material through macroporous resin purification were obtained, and determined by gas chromatography-mass spectrometry (GC-MS). RESULTS: The algicidal effect as follows: ethyl acetate extract > acetone crude extract > ethanol crude extract > water crude extract. Meanwhile, the inhibitory substances of Salvinia natans (L.) All. may be: diacetone alcohol, methyl isobutenyl ketone, 5-methyl-2-(1-methylethyl)-1-hexanol, pentadecanal, 14-heptadecenal, cumene, butyl acetate, ascorbyl dipalmitate, 1, 2-benzenedicarboxylic acid, mono (2- ethylhexyl) ester, dibutyl phthalate and phthalic acid, butyl undecane ester. CONCLUSION: The algal inhibiting effect research of Salvinia natans (L.) All., as well as its separation and identification of allelochemicals supplys theoretical basis and practical evidence not only for algae control, but also exploitation of algal inhibiting agent.

[Inhibition effect of aquaculture water of Salvinia natans (L.) All. on Microcystis aeruginosa PCC7806].

OBJECTIVE: To study the inhibiting effect of aquaculture water of Salvinia natans (L.) All. on Microcystis aeruginosa and the mechanism. METHODS: Microcystis aeruginosa of 7.5 x 10(5) cells/mL was treated by the culture water of Salvinia natans density of 5%, 10%, 20% and 40%, respectively. The inhibition ratios were calculated, conductivity of algal cells, content of nucleic acid and protein in algae solution, influence of superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were measured. RESULTS: The inhibition rate of 40% treatment group up to 100% on the fourth day. The inhibition rate of 5% treatment group up to 65% on the 7th day. The conductivity of algae cell gone up while the concentration of cultured water was increasing, as well as its content of nucleic acid, protein and MDA. However, the activity of SOD rose at first and then fall down while the concentration of cultured water of Salvinia natans was increasing. CONCLUSION: The aquaculture water of Salvinia natans has a powerful inhibitory effect on Microcystis aeruginosa by changing the structure of algal cells and intracellular enzyme activity, etc.

[Joint actions of Myriophyllum verticillatum L and its rhizospheric microorganisms on Microcystis aeruginosa and the mathematical model analysis].

OBJECTIVE: To study the inhibition effect on blue-green algae of higher aquatic plants with their rhizosphere microorganisms and its mathematical model. METHODS: The inhibitory effects of sterile and containing bacterium Myriophyllum verticillatum L root extracts on Microcystis aeruginosa were studied respectively, and the difference-differential equation of algal growth and partial functional differential equation were established according to the algal inhibiting effect. RESULTS: (1) The sterile and containing bacterium Myriophyllum verticillatum L root extracts showed at some degree inhibitory effects on M. aeruginosa, and containing bacteria root extract had more potent algal inhibiting effect, and very lower half maximal effective concentration (EC50). (2) The established inhibitory mathematical models can effectively predicted and calculated algal densities and EC50 at varying exposure time and different environment. CONCLUSION: The rhizospheric microorganisms can effectively enhanced the inhibiting effect of Myriophyllum verticillatum L on M. aeruginosa.

Increased IL-22 level in allergic rhinitis significantly correlates with clinical severity.

BACKGROUND: IL-22 regulates various processes and has been linked to diverse effects. However, the importance of IL-22 in the pathogenesis of allergic rhinitis (AR) remains poorly understood. This study sought to evaluate the levels of IL-22 and IL-17A in AR patients and their association with clinical severity ofN AR. METHODS: Thirty-six AR patients and 22 normal controls were enrolled in this study. The frequencies of IL-22(+), IL-17A(+), and IL-9(+) T helper (Th) cells in peripheral blood of AR patients and normal controls were examined by flow cytometry. Serum levels of IL-22 and IL-17A in AR patients and normal controls were determined by ELISA. The clinical relevance of the percentages of IL-22(+) and IL-17A(+) Th cells as well as serum IL-22 and IL-17A levels were evaluated. RESULTS: The frequencies of IL-22(+) and IL-17A(+) Th cells, but not IL-9(+) Th cells, were significantly increased compared with those in normal controls (p < 0.05). Frequencies of IL-22(+) and IL-17A(+) Th cells in peripheral blood of AR patients significantly correlated with visual analog scale scores of nasal symptoms (nasal congestion and rhinorrhea; p < 0.05). Moreover, the serum levels of IL-22 and IL-17A were significantly increased compared with those in normal controls (p < 0.05) and significantly correlated with the levels of Dermatophagoides pteronyssinus and Dermatophagoides farinae specific IgE in AR patients. CONCLUSION: Our findings suggested that IL-22 as well as IL-17A may play an important role in the regulation of Th2-skewed inflammation in AR patients.

Interleukin-17A promotes MUC5AC expression and goblet cell hyperplasia in nasal polyps via the Act1-mediated pathway.

BACKGROUND: Recent studies demonstrated that nasal polyps (NP) patients in China and other Asian regions possessed distinct Th17-dominant inflammation and enhanced tissue remodeling. However, the mechanism underlying these observations is not fully understood. This study sought to evaluate the association of interleukin (IL)-17A with MUC5AC expression and goblet cell hyperplasia in Chinese NP patients and to characterize the signaling pathway underlying IL-17A-induced MUC5AC expression in vitro. METHOD: We enrolled 25 NP patients and 22 normal controls and examined the expression of IL-17A, MUC5AC and act1 in polyp tissues by immunohistochemical (IHC) staining, quantitative polymerase chain reaction (qPCR) and western blot. Moreover, by using an in vitro culture system of polyp epithelial cells (PECs), IL-17A-induced gene expression was screened in cultured PECs by DNA microarray. The expression of IL-17RA, IL-17RC, act1 and MUC5AC and the activation of the MAPK pathway (ERK, p38 and JNK), were further examined in cultured PECs and NCI-H292 cells by qPCR and western blotting, respectively. RESULTS: We found that increased IL-17A production was significantly correlated with MUC5AC and act1 expression and goblet cell hyperplasia in polyp tissues (p<0.05). IL-17A significantly stimulated the expression of IL-17RA, IL-17RC, act1 and MUC5AC, and the activation of the MAPK pathway in cultured PECs and NCI-H292 cells (p<0.05). In addition, IL-17RA, IL-17RC and act1 siRNA significantly blocked IL-17A-induced MUC5AC production in vitro (p<0.05). CONCLUSION: Our results suggest that IL-17A plays a crucial role in stimulating the production of MUC5AC and goblet cell hyperplasia through the act1-mediated signaling pathway and may suggest a promising strategy for the management of Th17-dominant NP patients.

[Inhibition effects of Houttuynia cordata Thunb. on Microcystis aeruginosa].

OBJECTIVE: To research the inhibitory effect of Houttuynia cordata Thunb. on Microcystis aeruginosa. METHODS: M. aeruginosat were treated respectively by H. cordata leaching solution or H. cordata extracts. H. cordata leaching solution extracted by water and the H. cordata extracts extracted by organic solvent (acetone, ethyl acetate, petroleum ether and ethanol, respectively). The inhibition ratios were calculated according to the M. aeruginosa densities, and the allelochemicals of the extract that had the best inhibitiory effect on M. aeruginosa were identified by GC-MS analysis. RESULTS: It was proved that leaching solution of H. cordata and four crude extracts had good inhibitory effect on M. aeruginosa. The inhibitory effects of the four crude extracts were the fraction extracted by ethyl acetate, the fraction extracted by ethanol, the fraction extracted by acetone and the fraction extracted by petroleum ether form strong to weak in turn. Then, the allelochemicals of the fraction extracted by ethyl acetate were indentified, mainly including acetonyldimethylcarbinol, 2,2-dimethyl-3-hexanone, 6-chlorohexanoic and 4-cyanophenyl ester. CONCLUSION: H. cordata has strong inhibitory effect on water-blooming cyanobacteria and the potential to develop into an ecological M. aeruginosa inhibiting agent.

The antimicrobial protein short palate, lung, and nasal epithelium clone 1 (SPLUNC1) is differentially modulated in eosinophilic and noneosinophilic chronic rhinosinusitis with nasal polyps.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a highly heterogeneous disease with aberrant host defense responses. However, whether innate immunity is similarly impaired in patients with eosinophilic and those with noneosinophilic CRSwNP remains unclear. OBJECTIVES: We sought to evaluate the expression and possible modulation of short palate, lung, and nasal epithelium clone 1 (SPLUNC1), an innate immune molecule, in the 2 CRSwNP subsets. METHODS: Polyp tissue and uncinate processes were collected from 40 patients with CRSwNP, 27 patients with chronic rhinosinusitis without nasal polyps (CRSsNP), and 22 control subjects. Expression of SPLUNC1; Toll-like receptor (TLR) 2, TLR3, and TLR4; and the proinflammatory cytokines IL-1α, IL-4, IL-13, IL-17A, and IFN-γ was examined in nasal tissues. Additionally, SPLUNC1 expression in response to specific inflammatory stimulation was measured in cultured polyp epithelial cells and A549 cells. RESULTS: Polyp tissues exhibited significantly decreased expression of SPLUNC1 and other innate immune molecules compared with uncinate process tissues from patients with CRSwNP (P < .05), patients with CRSsNP, and healthy control subjects. Moreover, the eosinophilic CRSwNP subset exhibited significantly decreased SPLUNC1 expression and numbers of submucosal glands, as well as significantly increased IL-4 and IL-13 mRNA levels, compared with the noneosinophilic subset (P < .05). Accordingly, SPLUNC1 expression in polyp epithelial cells was significantly inhibited by IL-4 and IL-13 stimulation in vitro but was significantly upregulated after stimulation with TLR agonists and glucocorticoids (P < .05). CONCLUSION: Differential SPLUNC1 suppression between the eosinophilic and noneosinophilic CRSwNP subsets suggests that they possess distinct pathogenic mechanisms. This finding might benefit the design of appropriate therapeutic interventions targeted to each subset.

A hospital-based survey on the prevalence of bronchial asthma in patients with allergic rhinitis in southern China.

BACKGROUND: The prevalence of bronchial asthma (BA) and the underlying risk factors in patients with allergic rhinitis (AR) in China are largely unknown. Thus, this study is designed to assess the BA comorbidity in AR patients in two cities (Guangzhou and Zhuhai) of southern China and to determine the risk factors of BA in these AR patients. METHODS: We performed a cross-sectional, hospital-based survey in two modernized cities in southern China. The BA prevalence was evaluated in 1931 AR patients. Participants were asked to complete a questionnaire containing specific items for AR and BA. A logistic regression analysis was used to assess the risk factors of BA comorbidity in AR patients. RESULTS: The prevalence of concomitant BA in AR patients is 5.33% (103/1931). Most of the participants (98.4%) were sensitized to more than one allergen, and the most common sensitization was to house-dust mites. The strongest risk factor of BA determined by a multiple logistic regression analysis was a duration of AR of >5 years (adjusted odds ratio [OR], 8.67; 95% confidence interval [CI], 3.74-20.06), followed by smoking (adjusted OR, 7.21; 95% CI, 1.86-8.23) and self-medication with antibiotics (adjusted OR, 6.35; 95% CI, 3.43-11.78). CONCLUSION: Our findings suggested the risk factors of concomitant BA in AR patients may be helpful to establish preventive strategies.

Suppression of TIM-1 predicates clinical efficacy of sublingual immunotherapy for allergic rhinitis in children.

OBJECTIVE: To evaluate the clinical efficacy of sublingual immunotherapy (SLIT) with house-dust mite (HDM) extract and to examine the change of biomarkers (TIM-1, IL-5 and IL-10) after 6-month SLIT in children with allergic rhinitis (AR). METHODS: One hundred and sixteen HDM-sensitized children with persistent AR were enrolled to assess the clinical efficacy of SLIT by determining the individual nasal symptom score (INSS) and total nasal symptom scores (TNSS) after 6-month SLIT. Moreover, the mRNA expression of TIM-1, IL-5 and IL-10 in peripheral blood mononuclear cells (PBMCs) was examined in 16 well-controlled and 12 uncontrolled AR patients using quantitative reverse transcription polymerase chain reaction (qRT-PCR). RESULTS: After 6-month SLIT, both TNSS and INSS scores were significantly decreased compared with the baseline value (p < 0.01). The rates for well-controlled, partly controlled and uncontrolled children were 43.1%, 32.8% and 24.1%, respectively. Accordingly, the mRNA levels of TIM-1 and IL-5 decreased significantly and IL-10 mRNA level increased significantly compared with the baseline value in well-controlled children (p < 0.05). CONCLUSION: Our findings suggest SLIT with HDM extract is effective and safe for AR children and TIM-1 may be considered as an indicator for evaluating the clinical efficacy of SLIT.

Sensitivity of MUC5AC to topical corticosteroid is negatively associated with interleukin-17A in patients with allergic rhinitis.

BACKGROUND: Although Interleukin (IL)-17A has been suggested to play a role in corticosteroid hyporesponsiveness, whether IL-17A is able to affect the sensitivity of MUC5AC to intranasal corticosteroid treatment in patients with allergic rhinitis (AR) is unclear. METHODS: Twenty patients with moderate to severe AR were enrolled in this study and the expression of MUC5AC, IL-17A, and glucocorticoid receptor beta (GR beta) was detected using immunochemical staining and quantitative reverse transcription polymerase chain reaction (RT-PCR) before and after treatment with fluticasone propionate (FP) nasal spray for 4 weeks, respectively. In addition, the effects of FP on IL-13- and IL-17A-induced MUC5AC and GR beta were also evaluated in the primarily cultured human nasal epithelial cells (HNECs) in vitro. RESULTS: The increased MUC5AC expression was associated with IL-17A levels in AR, and IL-17A was found to affect the inhibition of MUC5AC by corticosteroid treatment. Both IL-13 and IL-17A significantly promoted MUC5AC mRNA expression in HNECs, and FP treatment was able to significantly inhibit MUC5AC mRNA expression in HNECs induced by IL-13 but not for that induced by IL-17A. Also, IL-17A but not IL-13 promoted GR beta mRNA expression in HNECs, which was not affected by administration of corticosteroid. CONCLUSION: Our results suggest that the sensitivity of MUC5AC to topical corticosteroid is negatively associated with IL-17A in AR patients. This might help us to gain more insight into the pathophysiology and the pharmacotherapeutic mechanisms on AR treatment.

Increased neutrophilia in nasal polyps reduces the response to oral corticosteroid therapy.

BACKGROUND: Nasal polyps (NPs) are characterized by eosinophilic inflammation, which is generally considered sensitive to corticosteroid treatment. OBJECTIVES: We evaluated levels of neutrophilia in NPs and investigated whether increased neutrophilia in polyp tissue affected the response to corticosteroid treatment. METHODS: We studied 3 independent cross-sectional groups of patients with NPs. Levels of infiltration by different types of inflammatory cells were determined by using immunohistochemical analyses and compared with those seen in control nasal tissues from subjects without NPs. Levels of inflammatory mediators were measured by using real-time PCR, ELISA, and FlowCytomix analyses. Patients with NPs received oral corticosteroid therapy (30 mg of prednisone once daily for 7 days); clinical parameters of efficacy were associated with NP phenotypes. RESULTS: Among patients with NPs, 76.5% had an eosinophilic phenotype, 46.0% had a neutrophilic phenotype, and 35.8% had a mixed phenotype (indicated by double staining). Overall, patients' symptoms improved after corticosteroid treatment; numbers of eosinophils and levels of their mediators (IL-4 and IL-5), but not numbers of neutrophils or levels of their mediators (IL-8 and interferon-inducible protein 10), were reduced (P< .05). After corticosteroid treatment, patients with the nonneutrophilic phenotype (neutrophil negative) had significantly greater reductions in bilateral polyp size scores, nasal congestion scores, total nasal symptom scores, and nasal resistance than patients with the neutrophilic phenotype (neutrophil positive, P< .05). CONCLUSIONS: There are different phenotypes of NPs based on the type of immune cell infiltrate and cytokines produced (eosinophilic or neutrophilic). Patients with the neutrophilic phenotype have less response to treatment with corticosteroids based on symptom scores.