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Increased temperature and acidification are two important environmental factors affecting algal growth in marine ecosystems with the increase of atmospheric CO2. The dinoflagellate Amphidinium carterae and the diatom Phaeodactylum tricornutum were chosen to study the effect of warming and acidification on their sulfate assimilation and reduction processes by continuous incubation at different temperatures (15, 20 and 25 °C) and pHNBS values (8.10, 7.80 and 7.60). Variations in associated sulfur compounds, namely sulfate, dimethylsulfoniopropionate (DMSP), dimethylsulfide (DMS) and acrylic acid (AA) were observed. The largest sulfate uptake was at 25 °C for A. carterae and at 20 °C for P. tricornutum, however, the optimal growth temperature for both microalgae was 20 °C. The release of DMSP and DMS decreased in A. carterae while they increased in P. tricornutum under the condition of increased temperature. Seawater acidification increased the uptake of sulfate and promoted the growth of the microalgae. Acidification also reduced the release of DMSP, dissolved DMSP (DMSPd), DMS and AA from A. carterae with mean values of 55%, 22%, 9% and 40%, respectively. However, acidification increased the release of DMSP and DMSPd by P. tricornutum with mean values of 44% and 186%, the release of DMS was inhibited (25%) and with no significant difference in the release of AA (2%). Amino acids were found to inhibit the uptake of sulfate by the two microalgae, and the inhibitory effect of cysteine was found to be stronger than that of methionine. The inhibitory effect of amino acids was temperature sensitive and relatively weak at 20 °C. Besides, acidification could enhance the inhibitory effect and was evident in A. carterae. The sulfur metabolism intermediates (cysteine and methionine) have a feedback regulation effect on the sulfate absorption process of algae. [ABSTRACT FROM AUTHOR]

Dimethyl sulfide (DMS) is an important and dominant trace gas that is transferred from the ocean to the atmosphere; however, the production of DMS from marine algae is still rudimentary, with the enzymatic cleavage of dimethylsulfoniopropionate (DMSP) to DMS and acrylic acid (AA), one of the main considered pathways. Dissolved DMSP (DMSPd) was supplied to batch cultures of Prorocentrum minimum at different algal growth stages and the kinetics of overall DMSPd consumption and DMS (AA) production were investigated. The kinetics of overall DMSPd consumption and DMS (AA) production from DMSPd were different during the growth cycle. The cultures displayed Michaelis–Menten-type kinetics for DMS production during the entire growth period, which yielded an apparent half-saturation constant (Km(app)) value of 37.8 ± 12.8 μM and a maximum rate (Vmax) value of 75.6 ± 12.2 nmol min−1 (1010 cells)−1. The production rates of AA had a nearly linear fit over the concentration range of the added DMSPd except during mid-exponential growth phase. A Km(app) value of 1.73 ± 0.75 μM and a Vmax value of 2.36 ± 0.12 μmol min−1 (1010 cells)−1 were observed. The ratio of DMS/AA increased with the concentration of the added DMSPd, which was less than 12% during the entire growth period. The low ratios of DMS/(DMSP + AA), which ranged from 0.01 to 1.83%, demonstrate that degradation of DMSP tends to take a non-DMS-production pathway. The ratios of AA/(DMSP + AA) varied from 9 to 95% during the stationary phase and from 6 to 69% during the senescent phase and declined with substrate concentration when different concentrations of DMSPd were added. The degradation ratios of DMSPd were related to the initial concentrations of DMSPd. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) is a non-traditional regulator of the growth of plants and phytoplankton. Here, the growth of five marine phytoplankton species, Platymonas helgolandica var. tsingtaoensis, Platymonas subcordiformis, Skeletonema costatum, Gymnodinium sp., and Prorocentrum donghaiense, was monitored, and carbonate system parameters in the culture media were determined after adding different concentrations of NO and sodium nitroprusside (SNP, NO donor) solutions. The two dietary algae (P. helgolandica var. tsingtaoensis and P. subcordiformis) and three red tide algae (S. costatum, Gymnodinium sp., and P. donghaiense) showed different responses to the same NO concentration. The red tide algae were more sensitive to exogenous NO than the dietary algae. NO with a concentration of 1.4 × 10−6 mol L−1 had the optimal stimulatory effect on the growth of the microalgae and increased the cell density by 9.8–38.3%. SNP solution with a concentration of 100 μmol L−1 inhibited the growth of the two dietary algae, and the cell density decreased by 38.8–84.3%. The addition of 10 μmol L−1 SNP solution to the three red tide algae decreased the cell density by 95.3–99.9%. Low concentrations of SNP (0.1 μmol L−1 for the two dietary algae and 0.01 μmol L−1 for the red tide algae) slightly promoted the growth of microalgae. High concentrations of NO (100 μmol L−1 SNP) inhibited CO2 assimilation, whereas low concentrations of NO (0.01–1.0 μmol L−1 SNP) promoted CO2 assimilation, indicating that NO participates in the regulation of photosynthesis. [ABSTRACT FROM AUTHOR]

Production of dimethylsulfoniopropionate (DMSP), dimethylsulfide (DMS), and acrylic acid (AA) from 22 marine microalgae representing six phyla were examined at different growth stages. The concentrations of DMSP, DMS, and AA per cell in the media showed significant changes during the whole growth period, and the highest concentrations were found at the stationary growth phase or the senescent phase. Different species had different concentration levels of DMSP, DMS, and AA, among which Pyrrhophyta, Bacillariophyte, and Chrysophyta had relatively large release. The highest concentrations of DMSP, DMS, and AA were 56.70, 0.86, and 44.60 fmol cell−1 in Scrippsiella trochoidea , Prymnesiacee , and Karenia mikimotoi , respectively. The ratios of DMS/DMSP and AA/(DMSP+AA) in the 22 marine microalgae differed dramatically over the growth cycle. The DMS/DMSP ratios were <25%, indicating that only a small fraction of DMSP was converted to DMS by enzymatic cleavage. Moreover, there was a higher ratio of enzymatic degradation of DMSP in the senescent growth stage. The AA/(DMSP+AA) ratio, representing the degradation ratio of DMSP, increased significantly at the beginning of growth period and then decreased. Hence, the changes in these ratios could approximately illustrate the degradation mechanism of DMSP among diverse species at different growth phases. • High DMSP, DMS and AA concentrations were detected in Pyrrophyta and Bacillariophyta. • The maximum concentrations of DMSP and DMS appeared in the stationary growth stage. • The highest release of AA was observed in the early exponential growth period. • The maximum value of DMSP enzymatic degradation appeared in late growth phase. [ABSTRACT FROM AUTHOR]

Sialic acid (SA), as the ultimate epitope of polysaccharides, can act as a cap at the end of polysaccharide chains to prevent their overextension. Sialylation is the enzymatic process of transferring SA residues onto polysaccharides and is catalyzed by a group of enzymes known as sialyltransferases (SiaTs). It is noteworthy that the sialylation level of glycoproteins is significantly altered when digestive cancer occurs. And this alteration exhibits a close correlation with the progression of these cancers. In this review, from the perspective of altered SiaTs expression levels and changed glycoprotein sialylation patterns, we summarize the pathogenesis of gastric cancer (GC), colorectal cancer (CRC), pancreatic ductal adenocarcinoma (PDAC), and hepatocellular carcinoma (HCC). Furthermore, we propose potential early diagnostic biomarkers and prognostic indicators for different digestive cancers. Finally, we summarize the therapeutic value of sialylation in digestive system cancers. [Display omitted] • Sialylation level significantly altered during the oncogenesis of digestive cancers. • Structures of sialylated glycoproteins and interactions between SiaTs are complex. • Altered sialylation levels can be detected in sera, paving the way for diagnosis. • Reducing the burden of SAs weakens the function of sialylation in tumor cells. • The diagnostic and therapeutic value of sialylation need clinical trials to verify. [ABSTRACT FROM AUTHOR]

To examine the sulfate assimilation and reduction process and the regulation of illumination, diatom Phaeodactylum tricornutum and dinoflagellate Amphidinium carterae were selected for continuous simulation incubation under different photon flux densities (PFDs) (54, 108 and 162 μmol photons m−2 s−1), and concentration variations of related sulfur compounds sulfate, dimethylsulfoniopropionate (DMSP), dimethylsulfide (DMS) and acrylic acid (AA) in the culture system were observed. The optimal PFD for the growth of two microalgae was 108 μmol photons m−2 s−1. However, the maximum sulfate absorption occurred at 162 μmol photons m−2 s−1 for P. tricornutum and at 54 μmol photons m−2 s−1 for A. carterae. With the increase of PFD, the release of DMSP by P. tricornutum decreased while A. carterae increased. The largest release amount of DMS was 0.59 ± 0.05 fmol cells−1 for P. tricornutum and 2.61 ± 0.89 fmol cells−1 for A. carterae under their optimum growth light condition. The sulfate uptake of P. tricornutum was inhibited by the addition of amino acids, cysteine had a greater inhibitory effect than methionine, and the absorption process was controlled by light. The intermediate products of sulfur metabolism had an up–control effect on the sulfate uptake process of P. tricornutum. However, the addition of amino acids had no obvious effect on the sulfate absorption of A. carterae. • Illumination regulated sulfate assimilation of P. tricornutum and A. carterae. • 108 μmol photons m−2 s−1 was the optimum light condition for the algal growth. • Related sulfur compounds concentrations varied under different illumination. • Sulfur metabolic intermediates inhibited the sulfate uptake of P. tricornutum. • Sulfur metabolic intermediates had no obvious regulative law on A. carterae. [ABSTRACT FROM AUTHOR]

Telomerase is a promising diagnostic and prognostic biomarker for cancers. Sensitive, simple, and reliable telomerase activity detection is vital for cancer diagnosis. Herein, we developed an ultrasensitive visualized assay for telomerase activity that combined the exponential amplification reaction (EXPAR) and lateral flow assay for easy and quick signal readout, which we termed as a lateral flow readout-EXPAR (LFR-EXPAR) assay. In the LFR-EXPAR assay, telomerase elongation products initiate the exponential amplification reaction, the generated trigger hybridizes with the reporter to form the recognition site of the nicking enzyme, and the nicking enzyme cuts the reporter strand. The degradation of the reporter can be detected with a universal lateral flow dipstick and read out with the naked eye. After conducting a series of proof-of-concept investigations, the LFR-EXPAR assay was found to achieve a sensitivity comparable to that of a TRAP (telomere repeat amplification protocol) assay. The LFR-EXPAR assay can be used to realize ultrasensitive and point-of-care detection of telomerase without requiring specialized instruments, holding great promise for early cancer diagnosis. [ABSTRACT FROM AUTHOR]

By analyzing the sequencing results, we found that PKM2 was significantly enriched in the KEGG pathway associated with muscle development and was screened as a hub gene in the fast-growing group; hence, we speculate that PKM2 may be associated with the growth and development of Bian chickens. Keywords: miRNA-seq; skeletal muscle; Bian chicken; growth and development EN miRNA-seq skeletal muscle Bian chicken growth and development N.PAG N.PAG 15 04/26/22 20220415 NES 220415 1. Apart from research on genes related to Bian chicken growth, there are few studies on miRNA functions in Bian chicken growth. miRNA is a noncoding sequence with a length of approximately 22 nt, which inhibits the expression of target genes by binding to the 3'UTR region of mRNA [[5]]. In order to further explore the key DEMs and predicted target genes, we performed an interaction network analysis of genes enriched in KEGG pathways associated with muscle growth and development. [Extracted from the article]

Early diagnosis is important for improving the outcomes of keratoconus (KC). Stable expression and a closed-loop structure of circular RNAs (circRNAs) make them ideal for the diagnosis and treatment of diseases. However, the expression pattern and potential function of circRNAs in KC is not studied yet. Hence, this study explored the circRNA expression profile of KC corneas through transcriptome sequencing and circRNA expression profile analysis. The diagnostic potential of blood circRNAs for KC was explored by analysing the circRNAs' expression levels of fifty paired blood samples from patients with KC and normal controls. The results showed that 107 significantly upregulated and 145 significantly downregulated circRNAs (|fold change| ≥ 2.0, p -value <0.05) were identified in KC tissues. Eight top differently expressed circRNAs were further validated in more cornea samples. Among them, five circRNAs expressed in peripheral blood, and four circRNAs (circ_0006156, circ_0006117, circ_0000284 and circ_0001801) showed significant downregulation in KC patients' peripheral blood too. The blood circ_0000284 expression levels of early, moderate, and advanced KC patients both were significantly lower than the controls. The blood circ_0006117 expression levels present a positive correlation with corrected distance visual acuity values, and a negative correlation with back elevation values of KC eyes. Notably, the expression levels of these circRNAs distinguished KC patients from their healthy counterparts, with the area under the curve (AUC) of circ_0000284, circ_0001801, and circ_0006117 being 0.7306, 0.6871 and 0.6701, respectively. Further, the AUC value for five circRNAs under the logistic regression model was 0.8203, indicating that they can function as effective biomarkers for the KC diagnostics. In conclusion, the expression of circRNAs showed a relationship with KC, with four significantly differentially expressed circRNAs demonstrating potential as biomarkers for the disease. • The expression profile of circRNAs in the corneas was analysed by RNA-Seq. • A group of significantly regulated circRNAs in keratoconus tissues were identified. • Four significantly differentially expressed circRNAs in blood were identified. • Four circRNAs demonstrating potential as circulating biomarkers for the keratoconus. • Hsa_circ_0000284 has the best diagnostic performance in the diagnosis of keratoconus. [ABSTRACT FROM AUTHOR]

• NOx in wetlands was mainly generated from vegetation-covered sediments. • Denitrifiers dominated NO production, showing sensitivity to environmental gradients. • NO emissions would be underestimated without considering tidal pulses. Intertidal wetland sediments are an important source of atmospheric nitrogen oxides (NO x), but their contribution to the global NO x budget remains unclear. In this work, we conducted year-round and diurnal observations in the intertidal wetland of Jiaozhou Bay to explore their regional source-sink patterns and influence factors on NO x emissions (initially in the form of nitric oxide) and used a dynamic soil reactor to further extend the mechanisms underlying the tidal pulse of nitric oxide (NO) observed in our investigations. The annual fluxes of NO x in the vegetated wetland were significantly higher than those in the wetland without vegetation. Their annual variations could be attributed to changes in temperature and the amount of organic carbon in the sediment, which was derived from vegetated plants and promoted the carbon-nitrogen cycle. Anaerobic denitrifiers had advantages in the intertidal wetland sediment and accounted for the major NO production (63.8 %) but were still limited by nitrite and nitrate concentrations in the sediment. Moreover, the tidal pulse was likely a primary driver of NO x emissions from intertidal wetlands over short periods, which was not considered in previous investigations. The annual NO exchange flux considering the tide pulse contribution (8.93 ± 1.72 × 10–2 kg N ha–1 yr–1) was significantly higher than that of the non-pulse period (4.14 ± 1.13 × 10–2 kg N ha–1 yr–1) in our modeling result for the fluxes over the last decade. Therefore, the current measurement of NO x fluxes underestimated the actual gas emission without considering the tidal pulse. [Display omitted] [ABSTRACT FROM AUTHOR]

Brain-derived neurotrophic factor (BDNF)/tyrosine kinase receptor B (TrkB) pathway is a therapeutic target in cardiac diseases. A BDNF mimetic, 7,8-dihydroxyflavone (7,8-DHF), is emerging as a protective agent in cardiomyocytes; however, its potential role in cardiac fibroblasts (CFs) and fibrosis remains unknown. Thus, we aimed to explore the effects of 7,8-DHF on cardiac fibrosis and the possible mechanisms. Myocardial ischemia (MI) and transforming growth factor-β1 (TGF-β1) were used to establish models of cardiac fibrosis. Hematoxylin & eosin and Masson's trichrome stains were used for histological analysis and determination of collagen content in mouse myocardium. Cell viability kit, EdU (5-ethynyl-2′-deoxyuridine) assay and immunofluorescent stain were employed to examine the effects of 7,8-DHF on the proliferation and collagen production of CFs. The levels of collagen I, α-smooth muscle actin (α-SMA), TGF-β1, Smad2/3, and Akt as well as circadian rhythm-related signals including brain and muscle Arnt-like protein 1 (Bmal1), period 2 (Per2), and cryptochrome 2 (Cry2) were analyzed. Treatment with 7,8-DHF markedly alleviated cardiac fibrosis in MI mice. It inhibited the activity of CFs accompanied by decreasing number of EdU-positive cells and downregulation of collagen I, α-SMA, TGF-β1, and phosphorylation of Smad2/3. 7,8-DHF significantly restored the dysregulation of Bmal1, Per2, and Cry2, but inhibited the overactive Akt. Further, inhibition of Bmal1 by SR9009 effectively attenuated CFs proliferation and collagen production of CFs. In summary, these findings indicate that 7,8-DHF attenuates cardiac fibrosis and regulates circadian rhythmic signals, at least partly, by inhibiting Bmal1/Akt pathway, which may provide new insights into therapeutic cardiac remodeling. [Display omitted] • 7,8-DHF alleviates ischemia-induced cardiac fibrosis. • 7,8-DHF inhibits the proliferation and differentiation of cardiac fibroblasts. • 7,8-DHF restores circadian rhythm and Akt signals in cardiac fibrosis. • Inhibition of Bmal1 by SR9009 inhibits the activity of cardiac fibroblasts. [ABSTRACT FROM AUTHOR]

As the degradation products of dimethylsulfoniopropionate (DMSP), dimethylsulfide (DMS) and acrylic acid (AA) are crucial to the sulfur cycle in the ocean. However, the biogeochemical processes of DMSP, DMS, and AA remain unclear. A monthly investigation was conducted to determine the DMSP, DMS, and AA concentrations and related parameters in the surface water of Jiaozhou Bay, a semi-enclosed bay in the western Yellow Sea, from December 2010 to November 2011. The monthly mean concentrations of DMSP, DMS, and AA were in the ranges of 5.02–27.25 nmol L−1, 0.41–3.14 nmol L−1, and below the detection limit–301.75 nmol L−1, respectively, showing significant seasonal variations with higher concentrations in summer than in autumn. The results were attributed to a combination of biogenic factors, including phytoplankton, zooplankton, and bacteria, as well as environmental factors, such as temperature and nutrients. The DMSP, DMS, and AA concentrations were not significantly correlated with chlorophyll a and bacterial abundance because of the influence of the community structure and anthropogenic activities. DMS was mainly produced by the enzymatic cleavage of DMSP, whereas AA was affected primarily by terrigenous input. The monthly mean sea-to-air fluxes of DMS ranged from 0.74 (in Apr) to 6.55 (in Jan) μmol m−2 d−1 with an average of 2.80 μmol m−2 d−1. • DMSP, DMS, and AA showed significant seasonal variations. • Biogenic sulfur variation was a combination of biogenic and environmental factors. • The monthly mean sea-to-air fluxes of DMS was estimated. [ABSTRACT FROM AUTHOR]