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1.
J Antibiot (Tokyo) ; 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32157185

RESUMO

Four 10-membered ring resorcylic acid lactones (RALs) including a new compound hispidulactone F (1) and three known analogs hispidulactone B (2), 2 R, 4R-sonnerlactone (3), and 2 R, 4S-sonnerlactone (4) were isolated from the special bioenvironmental desert plant endophytic fungus Chaetosphaeronema hispidulum. The structure of the new compound hispidulactone F (1) was determined by extensive spectra analysis including HR-ESI-MS, NMR (1H, 13C, 1H-1H COSY, HSQC, and HMBC). Hispidulactone F (1) and hispidulactone B (2) were a pair of stereoisomers at C-3, whereas 2 R, 4R-sonnerlactone (3) and 2 R, 4S-sonnerlactone (4) were another pair of stereoisomers at C-4. The stereochemistries of the hydroxyl groups at C-3 in 1 and 2, and at C-4 in 3 and 4 were first determined by modified Mosher's reactions. Thus, the absolute configuration C-3 in hispidulactone B (2) was not right in our previous report, and was rectified to be R. Compounds 1 and 4 were evaluated for their cytotoxic effects on the proliferation of HepG2. The possible biosynthetic pathway of compounds 1-4 was also presented.

2.
Fish Shellfish Immunol ; 100: 137-145, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32151686

RESUMO

Cobalt (Co) is an important component of vitamin B12, but is toxic to aquatic animals at a high level. In this study, the Pacific white shrimp, Litopenaeus vannamei were exposed to three Co concentrations (0, 100, and 1000 µg/L) for 4 weeks. The survival and condition factor in shrimp exposed to the Co treatments were not different from the control, but the shrimp exposed to 100 µg Co/L gained more weight than in other two groups, and the shrimp exposed to 1000 µg Co/L gained less weight than in other groups. The SOD and GSH-PX activities were higher in shrimp exposed to 100 µg Co/L, but lower in the shrimp exposed to 100 µg Co/L compared with the control, respectively. The MDA contents in the hepatopancreas decreased in the 100 µg Co/L, but increased in the 1000 µg Co/L. The serum lysozyme decreased with ambient cobalt, was lower in the shrimp exposed to 1000 µg Co/L than in other two groups. The expression of C-type lectin 3 was down-regulated by Co concentrations. The Toll and immune deficiency in shrimp exposed to 100 µg Co/L was higher than in other two groups. The mucin-1 was lower in the 1000 µg Co/L group than in other two groups, but mucin-2 and mucin-5AC were higher in the 1000 µg Co/L group than in the control. With increasing Co concentration, Shannon and Simpson indexes of the intestinal microbial communities were decreased. The abundance of pathogenic bacteria (Ruegeria and Vibrio) increased in both Co groups. This study indicates that chronic exposure to waterborne cobalt could affect growth, cause oxidative stress, stimulate the immune response, damage intestinal histology, and reshape intestinal microbiota community L. vannamei.

3.
Fish Shellfish Immunol ; 100: 445-455, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32173448

RESUMO

Copper can be accumulated in water through excessive sewage discharge or residual algaecide to generate toxic effect to aquatic animals. In this study, the juvenile of Pacific white shrimp, Litopenaeus vannamei was exposed to 0 (control), 0.05, 0.1, 0.2, 0.5 or 1 mg Cu2+ L-1 for 30 days. Growth, immune function, anti-oxidative status and gut microbiota were evaluated. Weight gain and specific growth rate of L. vannamei were significantly decreased with the increase of ambient Cu2+. Enlarged lumen and ruptured cells were found in the hepatopancreas of shrimp in the 0.5 or 1 mg Cu2+ L-1 treatment. Total hemocyte counts of shrimp in 0.5 or 1 mg Cu2+ L-1 were significantly lower than in the control. The hemocyanin concentration was also significantly increased in 0.2 or 0.5 mg Cu2+ L-1. Lysozyme contents were reduced in shrimp when Cu2+ exceeded 0.2 mg L-1. Meanwhile, activities of superoxide dismutase and glutathione peroxidase were increased in the hepatopancreas and the activity of Na+-K+ ATPase was decreased in the gills with increasing Cu2+. The mRNA expressions of immune deficiency, toll-like receptor and caspase-3 were all significantly higher in the hepatopancreas in 0.05 mg Cu2+ L-1 than in the control. For the diversity of intestinal microbes, Bacteroidetes significantly decreased in 1 mg Cu2+ L-1 at the phylum level. KEGG pathway analysis demonstrates that 1 mg L-1 Cu2+ can significantly alter metabolism, cellular processes and environmental information processing. This study indicates that the concentration of 1 mg L-1 Cu can negatively impact growth, hemolymph immunity, anti-oxidative capacity and gut microbiota composition of L. vannamei.

4.
Molecules ; 25(5)2020 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-32182779

RESUMO

Three new inositol angelate compounds (1-3) and two new tirucallane-type alkaloids (4 and 5) were isolated from the Amoora dasyclada, and their structures were established mainly by means of combination of 1D and 2D nuclear magnetic resonance and HR-ESI-MS. Based on cytotoxicity testing, compounds 4 and 5 exhibited significant cytotoxic activity against human cancer cell line HepG2 with IC50 value at 8.4 and 13.2 µM. In addition, compounds 4 and 5 also showed remarkable growth inhibitory activity to Artemia salina larvae.

6.
PM R ; 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32030890

RESUMO

BACKGROUND: Pain severity of postpartum pelvic girdle pain (PGP) does not seem closely related to the symphysis gap. OBJECTIVE: To determine the relationship between the pubic symphysis gap and postpartum PGP in women treated with the squeeze-and-clap maneuver. DESIGN: Retrospective study. SETTING: Hospital Clinic PATIENTS: 32 patients with postpartum PGP. METHODS: The patients were grouped by the pubic symphysis gap as: group A (6-11 mm), group B (12-20 mm), and group C (21-30 mm). MAIN OUTCOME MEASUREMENTS: GP severity was measured by visual analogue scale (VAS). The symphysis gap was measured on radiographs. All patients were treated with the squeeze-and-clap maneuver. The VAS scores and the symphysis gaps at the first clinic visit and the second clinic visit 4-8 weeks later were analyzed. RESULTS: There was no significant difference in VAS scores between the three groups at the first clinic visit and the second clinic visit. VAS scores of the three groups were all significantly decreased at the second clinic visit compared with the first clinic visit (all P < .001). The symphysis gap was significantly decreased in group C at the second clinic visit (P = 0.004), but not in group A and group B. CONCLUSION: Pubic symphysis separation was not associated with pain severity of postpartum PGP.

8.
ChemSusChem ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32050057

RESUMO

Dissolution loss is the biggest issue for the organic electrode material, and nowadays the most popular strategy is to synthesize polymer or add much conductive carbon. In this paper, the issue is well addressed by monomolecular organics with relatively longer chain and larger size. Dye composing of quinones and carbazoles is proposed as the cathode material for Li secondary battery. The unique structure of more than three quinones collecting by carbazole bridge bond significantly improves the cycling stability. On the other hand, in addition to the widely-known enolization reaction of the quinone moiety, extra anion-doping capacity is supplied by the carbazole moiety. Owing to the multiple active sites, multi-electrons transfer redox and remarkable capacity enhancement is realized by Vet Yellow 3RT dye material. It shows stable capacity up to 340 mAh g-1 within 300 cycles. XRD, XPS and electrochemical measurement confirm the reactivity of carbonyl group and N-heterocycle toward Li+ and PF6- respectively. The work not only uncovers the new application of dye material, it also provides new avenue to address the dissolution loss and capacity breakthrough of the organics.

9.
Biofactors ; 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32078221

RESUMO

Colorectal cancer (CRC) refers to a deadly carcinoma following potent invasiveness and metastasis in advanced stage. Unfortunately, existing anti-CRC medicine is insufficient for chemotherapy in addition to adverse effects. Consequently, the candidate natural ingredient for treating CRC needs to be further developed. Our previous experiments report that genistein exerts beneficial effects to inhibit CRC cells via an antiproliferative mechanism. Based on the metastatic characteristics of staging CRC, anti-invasive and antimetastatic pharmacological activities using genistein remain uninvestigated. The scientific purpose of this study was to disclose the antimetastatic mechanism by using human and cell culture/nude mice samples, followed by biochemical tests and immunoassays. In human study, these CRC cases resulted in increased transforming growth factor beta-1 (TGF-ß1) levels, long noncoding RNA (lncRNA) TTTY18 expressions, followed with up-regulated Ki-67, serum and glucocorticoid regulated kinase 1 (SGK1), AktSer473 expressions. In a study in vitro, genistein-dosed CRC cells showed suppressed cell viability, promoted cell apoptosis, reduced Ki-67 positive cells, reduced cellular migration, down-regulated expressions of TTTY18, SGK1, AktSer473 , p38 MAPKTyr323 . In a further study in vivo, genistein-dosed tumor-bearing nude mice exhibited visibly reduced body mass, lowered tumorous TGF-ß1 and TTTY18 contents. In addition, intracellular numbers of SGK1, AktSer473 , p38 MAPKTyr323 positive cells were reduced dose-dependently. Collectively, these human and experimentative findings reveal that genistein pharmacologically exerts the potential antimetastatic CRC effects, possibly through a molecular mechanism of inhibiting TTTY18/Akt pathway in CRC cells.

10.
Phys Rev Lett ; 124(6): 063902, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109119

RESUMO

Strong coupling of two-dimensional semiconductor excitons with plasmonic resonators enables control of light-matter interaction at the subwavelength scale. Here we develop such strong coupling in plasmonic nanogap resonators, which allows modification of exciton strength by altering electromagnetic environments in nearby semiconductor monolayers. Using this system, we not only demonstrate a large vacuum Rabi splitting up to 163 meV and splitting features in photoluminescence spectra but also reveal that the effective exciton number contributing to the coupling can be reduced down to the single-digit level (N<10), which is 2 orders lower than that of previous systems, close to single-exciton based strong coupling. In addition, we prove that the strong coupling process is not affected by the large exciton coherence size that was previously believed to be detrimental to the formation of plasmon-exciton interaction. We provide a deeper understanding of strong coupling in two-dimensional semiconductors, paving the way for room-temperature quantum optics applications.

11.
Artigo em Inglês | MEDLINE | ID: mdl-32068196
12.
IUBMB Life ; 2020 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-32107843

RESUMO

Metastasis is responsible for 90% of colorectal cancer (CRC)-related deaths. In the present study, we identified a novel key regulator of CRC metastasis, leucine-rich repeats and immunoglobulin-like domains protein 3 (LRIG3), which was significantly decreased in CRC tissues and cell lines. Downregulation of LRIG3 was attributed to copy number loss and promoter hypermethylation. Low LRIG3 expression was positively correlated with metastatic clinical features and shorter survival time. Functional experiments showed that knockout of LRIG3 markedly enhanced CRC cell migration and invasion ability, whereas reintroduction of LRIG3 exerted the opposite effects. Regarding the mechanism, LRIG3 could facilitate the binding of DUSP6 to ERK1/2, resulting in the dephosphorylation of ERK1/2 and subsequently downregulation of slug, an epithelial-to-mesenchymal transition trigger, thereby constraining CRC cell motility. Importantly, LRIG3 expression was strongly negatively correlated with slug or p-ERK1/2 expression in CRC tissues. Collectively, our data suggest that LRIG3 is a novel suppressor of CRC metastasis, reactivation of LRIG3 may be a promising therapeutic approach for metastatic CRC patients.

13.
QJM ; 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31995198

RESUMO

Dermatomyositis is an idiopathic inflammatory myopathy with prominent and characteristic cutaneous manifestation along with proximal muscle weakness 1. Bohan and Peter defined five diagnostic criteria for dermatomyositis 1. Nasopharyngeal carcinoma with paraneoplastic dermatomyositis is commonly seen in area with higher incidence of nasopharyngeal carcinoma like Asia countries. The association of dermatomyositis and nasopharyngeal carcinoma does not influence the prognosis of malignancy 3. Side effects of radiation therapy may worsen the skin inflammation seen and mimic a relapsed in certain cases.

14.
Nat Nanotechnol ; 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-31988508

RESUMO

It has recently been shown that sulfur, a solid material in its elementary form S8, can stay in a supercooled state as liquid sulfur in an electrochemical cell. We establish that this newly discovered state could have implications for lithium-sulfur batteries. Here, through in situ studies of electrochemical sulfur generation, we show that liquid (supercooled) and solid elementary sulfur possess very different areal capacities over the same charging period. To control the physical state of sulfur, we studied its growth on two-dimensional layered materials. We found that on the basal plane, only liquid sulfur accumulates; by contrast, at the edge sites, liquid sulfur accumulates if the thickness of the two-dimensional material is small, whereas solid sulfur nucleates if the thickness is large (tens of nanometres). Correlating the sulfur states with their respective areal capacities, as well as controlling the growth of sulfur on two-dimensional materials, could provide insights for the design of future lithium-sulfur batteries.

15.
Biomed Pharmacother ; 124: 109835, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31958764

RESUMO

BACKGROUND: Epidemiologically, the disease incidence of colorectal cancer (CRC) ranks the third among all malignant tumors, and its mortality is the second following lung cancer. If unmanaged, CRC will develop fatal invasiveness and metastasis. However, existing chemotherapy is limitedly effective to treat metastatic CRC. Genistein, a functional phytoestrogen, is found with potent pharmacological activity against cancer cells. Therefore, this study was designed to characterize the clinical signatures of human CRC and to conduct anti-CRC experiments using genistein. METHODS: Briefly, the plasma, tumor, non-tumor samples of CRC patients were harvested for biological experiments, followed by analysis of clinical data. A pharmacological study in vitro of genistein for treating CRC cells was conducted accordingly. RESULTS: In diagnostic data, molecular tumor biomarkers in CRC patients were detected in plasma samples, consistent with pathological and imaging diagnoses of CRC. Notably, carcinomatous expressions of miR-95, serum glucocorticoid kinase 1 (SGK1), B-cell lymphoma-2 (Bcl-2), extracellular regulated protein kinase 1 (Erk1) in human CRC were notably elevated when compared to those in non-tumor controls. In pharmacological experiments using cell culture model, genistein-treated CRC cells resulted in reduced cellular viability, elevated lactate dehydrogenase (LDH) content, increased apoptotic cells and TdT mediated dUTP nick end labeling (TUNEL)-positive cells following a dose-dependent manner. Interestingly, down-regulated expressions of endogenous miR-95, SGK1, Bcl-2, Erk1 were observed after genistein treatments in a dose-dependent way. CONCLUSIONS: Collectively, the current clinical data indicate pathological markers of miR-95, SGK1, Erk1 in human CRC cases, and further experimental findings reveal that anti-CRC pharmacological mechanism using genistein was implicated in suppression of cellular miR-95, SGK1, Erk1 expressions. Together, genistein may be a promising bioactive compound for treating CRC.

16.
Magn Reson Imaging ; 68: 30-35, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31978516

RESUMO

OBJECTIVE: To prospectively evaluate the ability of IVIM-DWI and DCE-MRI in detecting early activity of sacroiliitis in rat model of ankylosing spondylitis by comparing with pathological results. METHODS: 20 wistar male rats were induced by bovine proteoglycan combined with complete/incomplete Freund's adjuvant as model group, and 20 healthy male rats were used as the control group. The parameters of IVIM-DWI and DCE-MRI in synovial regions of SIJ were measured respectively at 7th, 12th, 17th, and 22th weeks after the last induction, and the pathological features of SIJ were taken also, further studying the pathological characteristics of sacroiliac region. Independent sample t-test and one-way ANOVA were used for statistical analysis. The prediction parameters and diagnostic efficiency were compared by ROC curve. RESULTS: There was no significant difference of image parameters between the model and control groups at the 7th, 12th weeks after the last induction, and there were no positive findings in histopathological examination at the same time. At the 17th week after induction, the f and Fenh%, Senh% between the model and the control groups were statistically significant. At the 22th week, there was a statistically significant increase all the values in model group than those in control group (P < 0.05). Histologic examination confirmed inflmmtorycell infiitrtion at the 17th week and pannus forming of synovium on the surface of cartilage at the 22th week in the model groups. The Fenh%, Senh%, Dslow and f had the moderate diagnostic efficiency and the areas under the curve were 0.77, 0.75, 0.77 and 0.82 respectively. The Senh% demonstrated the highest sensitivity (71.4%) and f demonstrated the highest specificity (95.0%). CONCLUSION: IVIM-DWI and DCE-MRI can be used as the sensitive imaging methods to detect and accurate diagnosis the early activity of sacroiliitis in AS.

17.
Biomark Med ; 14(3): 239-248, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31984757

RESUMO

Aim: To investigate the role of miR-485-5p in colorectal cancer (CRC). Methodology: The level of miR-485-5p in serum and cell lines were measured by quantitative real-time polymerase chain reaction, and analyzed the diagnostic and prognostic value. Additionally, the biological effect of miR-485-5p on CRC cells was also explored in vitro. Results: The receiver operating characteristic (ROC) curves analysis revealed that miR-485-5p was a diagnostic candidate. Kaplan-Meier analyses demonstrated that patients with low serum miR-485-5p had shorter overall survival. In addition, the result of cox regression model indicated that miR-485-5p was not an independent risk factor for progression. Functional study revealed that overexpression of miR-485-5p could inhibit CRC cell proliferation, invasion and facilitates cell apoptosis. Conclusion: Our study revealed that miR-485-5p was a tumor suppressor and it could serve as a potential prognostic biomarker in CRC.

18.
QJM ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31917404

RESUMO

Kayser-Fleischer rings was first describe in year 1934 due to the abnormal accumulation of copper1. They are brownish rings resulting from pigmented granular cooper deposits on the Descemet's membrane. The cooper deposition are more pronounced in the superior and inferior cornea poles best seen from a slit-lamp1-2. Kayser-Fleischer rings are highly suggestive of Wilson's disease but have been reported in other diseases like cholestasis and primary biliary cirrhosis2. Kayser-Fleischer rings can be seen in 95% of cases of Wilson disease with neurological or psychiatry symptoms and about 55-65% of cases with hepatic involvement2-3. Wilson disease is an inborn error of copper metabolism and can manifest with hepatic, neurologic or psychiatric symptoms3.

19.
Fish Shellfish Immunol ; 97: 593-601, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31891810

RESUMO

The T-2 toxin is a trichothecene mycotoxin and is highly toxic to aquatic animals, but little is known on its toxic effect in crustaceans. In the present study, the crab juveniles were fed with diets containing four levels of T-2 toxin: 0 (control), 0.6 (T1), 2.5 (T2) and 5.0 (T3) mg/kg diet for 56 days to evaluate its impact on the juvenile of Chinese mitten crab (Eriocheir sinensis). The crabs fed the T-2 toxin diets had significantly lower weight gain and specific growth rate than those fed the control diet. Moreover, crab survival in T3 group was obviously lower than that in the control. Oxidative stress occurred in all the treatment groups as indicated by higher activities of total superoxide dismutase, glutathione peroxidase, and total antioxidant capacity than those in the control. The total hemocyte count, respiratory burst, phenoloxidase in the hemolymph, and phenoloxidase, acid phosphatase and alkaline phosphatase in the hepatopancreas of crabs fed T-2 toxin were significantly lower than those in the control. The transcriptional expressions of lipopolysaccharide-induced TNF-alpha factor, relish, and the apoptosis genes in the hepatopancreas were induced by dietary T-2 toxin. The genes related to detoxication including cytochrome P450 gene superfamily and glutathione S transferase were induced in low concentration, then decreased in high concentration. Dietary T-2 toxin damaged the hepatopancreas structure, especially as seen in the detached basal membrane of hepatopancreatic tubules. This study indicates that dietary T-2 toxin can reduce growth performance, deteriorate health status and cause hepatopancreas dysfunction in crabs.

20.
J Cell Sci ; 133(4)2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31974116

RESUMO

Elevated replication stress is evident at telomeres of about 10-15% of cancer cells, which maintain their telomeres via a homologous recombination (HR)-based mechanism, referred to as alternative lengthening of telomeres (ALT). How ALT cells resolve replication stress to support their growth remains incompletely characterized. Here, we report that CSB (also known as ERCC6) promotes recruitment of HR repair proteins (MRN, BRCA1, BLM and RPA32) and POLD3 to ALT telomeres, a process that requires the ATPase activity of CSB and is controlled by ATM- and CDK2-dependent phosphorylation. Loss of CSB stimulates telomeric recruitment of MUS81 and SLX4, components of the structure-specific MUS81-EME1-SLX1-SLX4 (MUS-SLX) endonuclease complex, suggesting that CSB restricts MUS-SLX-mediated processing of stalled forks at ALT telomeres. Loss of CSB coupled with depletion of SMARCAL1, a chromatin remodeler implicated in catalyzing regression of stalled forks, synergistically promotes not only telomeric recruitment of MUS81 but also the formation of fragile telomeres, the latter of which is reported to arise from fork stalling. These results altogether suggest that CSB-mediated HR repair and SMARCAL1-mediated fork regression cooperate to prevent stalled forks from being processed into fragile telomeres in ALT cells.

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