Unvegetated flats occupy a large area in the intertidal zone. However, compared to vegetated areas, the carbon sequestration of unvegetated tidal flats is rarely quantified, even though these areas ...are highly threatened by human development and climate change. We determined benthic maximum gross primary production (GPPm), net primary production (NPP) and total respiration (TR) during emersion on seven tidal flats along a latitudinal gradient (from 22.48°N to 40.60°N) in winter and summer from 2012 to 2016 to assess the spatial and temporal variability of carbon dioxide flux. In winter, these processes decreased by 89%–104% towards higher latitudes. In summer, however, no clear trend was detected across the latitudinal gradient. Quadratic relationships between GPPm, NPP and TR and sediment temperature can be described along the latitudinal gradient. These curves showed maximum values of GPPm and NPP when the sediment temperatures reached 28.7 and 26.6°C respectively. TR increased almost linearly from 0 to 45°C. The maximum daily NPP across the latitudinal gradient averaged 0.24 ± 0.28 g C m−2 day−1, which was only 10%–20% of the global average of NPP of vegetated coastal habitats. Multiplying with the global area of unvegetated tidal flats, our results suggest that the contribution of NPP on unvegetated tidal flats to the coastal carbon cycle is small (11.04 ± 13.32 Tg C/year). If the land cover of vegetated habitats is continuously degraded to unvegetated tidal flats, the carbon sequestration capacity in the intertidal zone is expected to reduce by at least 13.10 Tg C/year, equivalent to 1% of global carbon emissions from land‐use change.
In winter, benthic production and respiration during emersion on unvegetated tidal flats along the latitudinal gradient decreased by 89%–104% towards higher latitudes. In summer, however, no clear trend was detected across the latitudinal gradient. Quadratic relationships between these processes and sediment temperatures can be described along the latitudinal gradient. The contribution of net primary production (NPP) on unvegetated tidal flats to the coastal carbon cycle is small. If the land cover of vegetated habitats is continuously degraded to unvegetated tidal flats, the NPP in the intertidal zone is expected to reduce by at least 13.10 Tg C/year.
Liver disorders have been recognized as one major health concern. Fucoidan, a sulfated polysaccharide extracted from the brown seaweed Fucus serratus, has previously been reported as an ...anti-inflammatory and antioxidant. However, the discovery and validation of its hepatoprotective properties and elucidation of its mechanisms of action are still unknown. The objective of the current study was to investigate the effect and possible modes of action of a treatment of fucoidan against thioacetamide (TAA)-induced liver injury in male C57BL/6 mice by serum biochemical and histological analyses. The mouse model for liver damage was developed by the administration of TAA thrice a week for six weeks. The mice with TAA-induced liver injury were orally administered fucoidan once a day for 42 days. The treated mice showed significantly higher body weights; food intakes; hepatic antioxidative enzymes (catalase, glutathione peroxidase (GPx), and superoxide dismutase (SOD)); and a lower serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and C-reactive protein (CRP) levels. Additionally, a reduced hepatic IL-6 level and a decreased expression of inflammatory-related genes, such as cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) mRNA was observed. These results demonstrated that fucoidan had a hepatoprotective effect on liver injury through the suppression of the inflammatory responses and acting as an antioxidant. In addition, here, we validated the use of fucoidan against liver disorders with supporting molecular data.
Neutrophils in Psoriasis Chiang, Chih-Chao; Cheng, Wei-Jen; Korinek, Michal ...
Frontiers in immunology,
10/2019, Volume:
10
Journal Article
Peer reviewed
Open access
Neutrophils are the most abundant innate immune cells. The pathogenic roles of neutrophils are related to chronic inflammation and autoimmune diseases. Psoriasis is a chronic systemic inflammatory ...disease affecting ~2-3% of the world population. The abundant presence of neutrophils in the psoriatic skin lesions serves as a typical histopathologic hallmark of psoriasis. Recent reports indicated that oxidative stress, granular components, and neutrophil extracellular traps from psoriatic neutrophils are related to the initial and maintenance phases of psoriasis. This review provides an overview on the recent (up to 2019) advances in understanding the role of neutrophils in the pathophysiology of psoriasis, including the effects of respiratory burst, degranulation, and neutrophil extracellular trap formation on psoriatic immunity and the clinical relationships.
Clozapine is widely employed in the treatment of schizophrenia. Compared with that of atypical first-generation antipsychotics, atypical second-generation antipsychotics such as clozapine have less ...severe side effects and may positively affect obesity and blood glucose level. However, no systematic study of clozapine’s adverse metabolic effects—such as changes in kidney and liver function, body weight, glucose and triglyceride levels, and retinopathy—was conducted. This research investigated how clozapine affects weight, the bodily distribution of chromium, liver damage, fatty liver scores, glucose homeostasis, renal impairment, and retinopathy in mice fed a high fat diet (HFD). We discovered that obese mice treated with clozapine gained more weight and had greater kidney, liver, and retroperitoneal and epididymal fat pad masses; higher daily food efficiency; higher serum or hepatic triglyceride, aspartate aminotransferase, alanine aminotransferase, blood urea nitrogen, and creatinine levels; and higher hepatic lipid regulation marker expression than did the HFD-fed control mice. Furthermore, the clozapine group mice exhibited insulin resistance, poorer insulin sensitivity, greater glucose intolerance, and less Akt phosphorylation; their GLUT4 expression was lower, they had renal damage, more reactive oxygen species, and IL-1 expression, and, finally, their levels of antioxidative enzymes (superoxide dismutase, glutathione peroxidase, and catalase) were lower. Moreover, clozapine reduced the thickness of retinal cell layers and increased iNOS and NF-κB expression; a net negative chromium balance occurred because more chromium was excreted through urine, and this influenced chromium mobilization, which did not help overcome the hyperglycemia. Our clozapine group had considerably higher fatty liver scores, which was supported by the findings of lowered adiponectin protein levels and increased FASN protein, PNPLA3 protein, FABP4 mRNA, and SREBP1 mRNA levels. We conclude that clozapine can worsen nonalcoholic fatty liver disease, diabetes, and kidney and retinal injury. Therefore, long-term administration of clozapine warrants higher attention.
Hyperbaric oxygen (HBO) improves angiogenesis. The effect of HBO on metastasis‐associated lung adenocarcinoma transcript 1 (MALAT1), a pro‐angiogenic long non‐coding RNA, in cardiac myocyte‐derived ...exosomes and acute myocardial infarction (AMI) is unknown. We aimed to investigate whether MALAT1 is altered in cardiac myocyte‐derived exosomes in response to HBO as well as the molecular regulatory mechanisms of MALAT1 in cardiac myocytes treated with HBO. Cardiac myocytes were cultured, and HBO was applied at 2.5 atmosphere absolute in a hyperbaric chamber. Exosomes were extracted from the culture media. A rat model of AMI generated by the ligation of the left anterior descending artery was used. HBO significantly increased MALAT1 expression in cardiac myocytes and HBO‐induced MALAT1 and exosomes attenuated miR‐92a expression after myocardial infarction. Expression of krüppel‐like factor 2 (KLF2) and CD31 was significantly decreased after infarction and HBO‐induced exosomes significantly reversed the expression. Silencing of MALAT1 using MALAT1‐locked nucleic acid GapmeR significantly attenuated KLF2 and CD31 protein expression after infarction induced by HBO‐induced exosomes. HBO‐induced exosomes also decreased infarct size significantly. HBO‐induced exosomes from cardiac myocytes up‐regulate MALAT1 to suppress miR‐92a expression and counteract the inhibitory effect of miR‐92a on KLF2 and CD31 expression in left ventricular myocardium after myocardial infarction to enhance neovascularization.
Aim
Reef fishes are commonly recognized as sentinels of the ongoing tropicalization in biogeographic transition zones between temperate and tropical areas. Despite the reliance of these marine ...ectotherms on the benthos, the importance of benthic habitat has rarely been considered as a factor constraining fish distribution. Therefore, our study aims at examining the consequences of both temperature and benthic variations on the fish fauna and diagnosing potential sentinels of these environmental changes.
Location
Taiwan, West Pacific.
Taxon
Teleostei (184 species).
Methods
We examined how the partitioning of habitats can influence the specialization of fish fauna along a latitudinal gradient. We diagnosed ‘specialist’ and ‘generalist’ fishes in this partitioning. For each specialist, we further evaluated whether its distribution is constrained by temperature, benthic habitat or both factors combined. The change in sea surface temperature over the last three decades was also monitored.
Results
Fish fauna showed the highest specialization when tropical and subtropical partitions of habitat were considered. Fifty‐one tropical specialists, 7 subtropical specialists and 21 possible generalists were identified. Among specialists, 13 species were associated with temperature, 19 with habitat and 26 with both factors. Steady warming occurred across latitudes, but was accentuated in the winter of subtropical habitat.
Main Conclusions
Our results suggested that the distribution of some specialist fishes was constrained only by temperature while the distribution of some others also depended on the availability of benthic habitats. Consequently, under global warming, the distribution of some specialists might shift in a manner that follows the movement of isotherms, while the distribution of others might also be conditioned by the poleward shifts of benthos. A temporal mismatch between the emergence of suitable thermal environments and the arrival of some specialists may exist. Therefore, the tropicalization of high‐latitude areas may be characterized by different waves of colonization.
目的
岩礁魚類常被認為是熱至溫帶這個生物地理過渡帶發生熱帶化時的指標類群。儘管這些魚類對底棲生物存在著依賴性，底棲棲地卻鮮少被當作是限制魚類分佈的重要因子之一。因此，本研究旨在探討溫度及底棲棲地的變化對該區魚類相的影響，並找出能作為對應這些環境變化的潛在指標性魚種。
地點
臺灣，西太平洋。
分類群
真骨魚 (184種)。
方法
沿著過渡帶的緯度梯度，我們檢試了底棲棲地的分群如何影響岩礁魚類群聚的專一性。我們試圖找出對此分群的專化與廣適魚種。針對這些專化魚種，我們進一步地評估其分佈和溫度、底棲棲地、或是兩者同時的關聯性。我們亦監測過去30年間海水表面溫度的變化。
結果
魚類群聚在底棲棲地被分成熱帶與亞熱帶兩群時有最高的專一性。我們一共找出了51種熱帶、7種亞熱帶專化魚類及21種潛在的廣適魚類。在這些專化種中，13種和溫度有關連， 19種和底棲棲地有關聯，而另外的26種則同時和此兩因子有關聯。穩定的暖化現象在各緯度都有出現，且在亞熱帶棲地的冬天尤其明顯。
主要結論
我們的結果顯示某些專化魚種的分佈僅受溫度限制，而另一些專化魚種的分布亦同時取決於底棲棲地的可得性。由此可知，在全球暖化下，某些專化魚種的分佈有可能會隨著等溫線的移動而發生改變，而其他專化魚種的分佈變化則可能同時受到底棲棲地極向移動的制約。適宜溫度環境之出現以及某些專化魚種的到來可能存在著時間上的不同。因此，高緯度地區的熱帶化有可能會出現魚種分批到來的特徵。
In recent years, techniques of using system disturbance data to validate generator models have been widely discussed. Dynamic model validation and calibration is becoming one of the important ...applications to smart grid initiative. As this kind of technique is utilized to validate generator model, procedures of data screening and reprocessing are essential because raw data obtained from measurement is not always satisfactory. Regarding model parameter calibration, system model is usually quite complicated with various parameters interacting with each other. Artificial intelligent tool is the prior option to save the laborious tuning process and enhance the parameter accuracy. This paper presents a guideline to validate and calibrate parameters of generating units using the record data from phasor measurement unit. Associated procedures for signal filtering on the measurement data, key parameters screening, intelligent search of model parameters, and cross check of legitimate parameters will be discussed in detail. Finally, two historical disturbance cases that happened in the Taiwan power (Taipower) system are applied in accordance with the proposed guideline to demonstrate its effectiveness on generator parameter validation and calibration.
Genotype I (GI) virus has replaced genotype III (GIII) virus as the dominant Japanese encephalitis virus (JEV) in the epidemic area of Asia. The mechanism underlying the genotype replacement remains ...unclear. Therefore, we focused our current study on investigating the roles of mosquito vector and amplifying host(s) in JEV genotype replacement by comparing the replication ability of GI and GIII viruses. GI and GIII viruses had similar infection rates and replicated to similar viral titers after blood meal feedings in Culex tritaeniorhynchus. However, GI virus yielded a higher viral titer in amplifying host-derived cells, especially at an elevated temperature, and produced an earlier and higher viremia in experimentally inoculated pigs, ducklings, and young chickens. Subsequently we identified the amplification advantage of viral genetic determinants from GI viruses by utilizing chimeric and recombinant JEVs (rJEVs). Compared to the recombinant GIII virus (rGIII virus), we observed that both the recombinant GI virus and the chimeric rJEVs encoding GI virus-derived NS1-3 genes supported higher replication ability in amplifying hosts. The replication advantage of the chimeric rJEVs was lost after introduction of a single substitution from a GIII viral mutation (NS2B-L99V, NS3-S78A, or NS3-D177E). In addition, the gain-of-function assay further elucidated that rGIII virus encoding GI virus NS2B-V99L/NS3-A78S/E177E substitutions re-gained the enhanced replication ability. Thus, we conclude that the replication advantage of GI virus in pigs and poultry is the result of three critical NS2B/NS3 substitutions. This may lead to more efficient transmission of GI virus than GIII virus in the amplifying host-mosquito cycle.
Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) plays a crucial role in the pathophysiological process associated with diabetes-related complications. The effect of high glucose ...levels on macrophage-derived exosomal MALAT1 is unknown. Therefore, we investigated the molecular regulatory mechanisms controlling exosomal MALAT1 in macrophages under high glucose treatment and the therapeutic target of macrophage-derived exosomal MALAT1 using a balloon injury model of vascular disease in diabetic rats. High glucose (25 mM) significantly increased MALAT1 expression in macrophage-derived exosomes. MALAT1 suppressed miR-150-5p expression in macrophage-derived exosomes under high-glucose conditions. Silencing MALAT1 using MALAT1 siRNA significantly reversed miR-150-5p expression induced by macrophage-derived exosomes. Macrophage-derived exosomes under high-glucose treatment significantly increased resistin expression in macrophages. Silencing MALAT1 and overexpression of miR-150-5p significantly decreased resistin expression induced by macrophage-derived exosomes. Overexpression of miR-150-5p significantly decreased resistin luciferase activity induced by macrophage-derived exosomes. Macrophage-derived exosome significantly decreased glucose uptake in macrophages and silencing MALAT1, resistin or overexpression of miR-150-5p significantly reversed glucose uptake. Balloon injury to the carotid artery significantly increased MALAT1 and resistin expression and significantly decreased miR-150-5p expression in arterial tissue. Silencing MALAT1 significantly reversed miR-150-5p expression in arterial tissue after balloon injury. Silencing MALAT1 or overexpression of miR-150-5p significantly reduced resistin expression after balloon injury. In conclusion, high glucose up-regulates MALAT1 to suppress miR-150-5p expression and counteracts the inhibitory effect of miR-150-5p on resistin expression in macrophages to promote vascular disease. Macrophage-derived exosomes containing MALAT1 may serve as a novel cell-free approach for the treatment of vascular disease in diabetes mellitus.
Spinocerebellar ataxia type 3 (SCA3), a hereditary and lethal neurodegenerative disease, is attributed to the abnormal accumulation of undegradable polyglutamine (polyQ), which is encoded by mutated ...ataxin-3 gene (
). The toxic fragments processed from mutant
can induce neuronal death, leading to the muscular incoordination of the human body. Some treatment strategies of SCA3 are preferentially focused on depleting the abnormal aggregates, which led to the discovery of small molecule
-butylidenephthalide (
-BP).
-BP-promoted autophagy protected the loss of Purkinje cell in the cerebellum that regulates the network associated with motor functions. We report that the
-BP treatment may be effective in treating SCA3 disease.
-BP treatment led to the depletion of mutant
with the expanded polyQ chain and the toxic fragments resulting in increased metabolic activity and alleviated atrophy of SCA3 murine cerebellum. Furthermore,
-BP treated animal and HEK-293
cell models could consistently show the depletion of aggregates through mTOR inhibition. With its unique mechanism, the two autophagic inhibitors Bafilomycin A1 and wortmannin could halt the
-BP-induced elimination of aggregates. Collectively,
-BP shows promising results for the treatment of SCA3.
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