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1.
Proc Natl Acad Sci U S A ; 121(11): e2313123121, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38437546

RESUMEN

Organized flaking techniques to obtain predetermined stone tools have been traced back to the early Acheulean (also known as mode 2) in Africa and are seen as indicative of the emergence of advanced technical abilities and in-depth planning skills among early humans. Here, we report one of the earliest known examples of prepared core technology in the archaeological record, at the Cenjiawan (CJW) site in the Nihewan basin of China, dated 1.1 Mya. The operational schemes reconstructed from the CJW refit sets, together with shaping patterns observed in the retouched tools, suggest that Nihewan basin toolmakers had the technical abilities of mode 2 hominins, and developed different survival strategies to adapt to local raw materials and environments. This finding predates the previously earliest known prepared core technology from Eurasia by 0.3 My, and the earliest known mode 2 sites in East Asia by a similar amount of time, thus suggesting that hominins with advanced technologies may have migrated into high latitude East Asia as early as 1.1 Mya.


Asunto(s)
Hominidae , Tecnología , Humanos , Animales , Asia Oriental , China , África
2.
J Geriatr Cardiol ; 21(4): 443-457, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38800544

RESUMEN

BACKGROUND: Chronic renal failure (CRF) patients are predisposed to arrhythmias, while the detailed mechanisms are unclear. We hypothesized the chronic inflammatory state of CRF patients may lead to cardiac sympathetic remodeling, increasing the incidence of ventricular arrhythmia (VA) and sudden cardiac death. And explored the role of atorvastatin and etanercept in this process. METHODS: A total of 48 rats were randomly divided into sham operation group (Sham group), CRF group, CRF + atorvastatin group (CRF + statin group), and CRF + etanercept group (CRF + rhTNFR-Fc group). Sympathetic nerve remodeling was assessed by immunofluorescence of growth-associated protein 43 (GAP-43) and tyrosine hydroxylase positive area fraction. Electrophysiological testing was performed to assess the incidence of VA by assessing the ventricular effective refractory period and ventricular fibrillation threshold. The levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta were determined by Western blotting and enzyme-linked immunosorbent assay. RESULTS: Echocardiogram showed that compared with the Sham group, left ventricular end-systolic diameter and ventricular weight/body weight ratio were significantly higher in the CRF group. Hematoxylin-eosin and Masson staining indicated that myocardial fibers were broken, disordered, and fibrotic in the CRF group. Western blotting, enzyme-linked immunosorbent assay, immunofluorescence and electrophysiological examination suggested that compared with the Sham group, GAP-43 and TNF-α proteins were significantly upregulated, GAP-43 and tyrosine hydroxylase positive nerve fiber area was increased, and ventricular fibrillation threshold was significantly decreased in the CRF group. The above effects were inhibited in the CRF + statin group and the CRF + rhTNFR-Fc group. CONCLUSIONS: In CRF rats, TNF-α was upregulated, cardiac sympathetic remodeling was more severe, and the nephrogenic cardiac sympathetic remodeling existed. Atorvastatin and etanercept could downregulate the expression of TNF-α or inhibit its activity, thus inhibited the above effects, and reduced the occurrence of VA and sudden cardiac death.

3.
Int J Biol Macromol ; 213: 394-403, 2022 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-35588979

RESUMEN

A novel polysaccharide (MSP-1) was isolated from the fruiting body of Morchella sextelata and purified using DEAE-52 and Sephadex G-75. The molecular weight of MSP-1 was 1.17 × 104 Da, as detected by HPLC analysis. The monosaccharide composition of MSP-1 was mannose and glucose at a ratio of 1.00: 1.25. Methylation and NMR results revealed that the backbone of MSP-1 was composed of →4)-ß-D-Manp-(1→, →4)-ß-D-Glcp-(1→, →4)-α-D-Glcp-(1→, and →4, 6)-α-D-Glcp-(1→. SEM images of MSP-1 presented a dense network structure with porous characterizations. The immunomodulatory activities of MSP-1 were evaluated using RAW264.7 cells, and the results showed that MSP-1 promoted proliferative and phagocytic activity and increased the production of NO, TNF-α and IL-6. These results indicated that MSP-1 exhibited significant immunomodulatory activities.


Asunto(s)
Ascomicetos , Proteína 1 de Superficie de Merozoito , Animales , Ascomicetos/química , Ratones , Peso Molecular , Monosacáridos/análisis , Polisacáridos/química , Células RAW 264.7
4.
J Nanosci Nanotechnol ; 20(4): 2114-2121, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-31492219

RESUMEN

Organophosphorus pesticides (OPs) are an important class of common pesticides. However, due to the abuse of organophosphorus pesticides, pesticide residue problems have been highlighted. In this study, the colorimetric detection method for OPs residues was established based on the broadspectrum aptamer. Through optimization, isocarbophos and omethoate were analyzed to verify the performance of the colorimetric assay. Under optimal conditions, the method proved effective for detecting an isocarbophos range of 50-1000 ng/mL and an omethoate range of 100-500 ng/mL. The protective effects of broad-spectrum aptamers and the split (28-mer P1+26-mer P2) aptamers on gold nanoparticles (AuNPs) were also comparatively studied. The present results suggested that the colorimetric assay based on broad-spectrum aptamer could be applied for a preliminary screening of different kinds of OPs.

5.
Carbohydr Polym ; 241: 116326, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32507202

RESUMEN

Two polysaccharides, named DOP-1 and DOP-2, with molecular weights of 6.8 kDa and 14.3 kDa, respectively, were isolated and purified from the stems of Dendrobium officinale. Monosaccharide composition, Fourier-transform infrared spectroscopy, methylation, and nuclear magnetic resonance analyses indicated that DOP-1 and DOP-2 may have a backbone consisted of →4)-ß-d-Glcp-(1→, →4)-ß-d-Manp-(1→, →4)-2-O-acetyl-ß-d-Manp-(1→ and →4)-3-O-acetyl-ß-d-Manp-(1→. In vivo assays showed that D. officinale polysaccharides (DOPs) exerted significant hypoglycemic effects accompanying increased serum insulin and glucagon-like peptide-1 (GLP-1) levels in streptozotocin-induced diabetic rats. Further in vitro experiments showed that DOP-induced GLP-1 secretion was inhibited by an intracellular calcium chelator, a Ca2+/calmodulin-dependent protein kinase (CaMK) II inhibitor, a specific calcium-sensing receptor antagonist, and a p38-mitogen-activated protein kinases (MAPK) inhibitor. These results indicated that DOPs may decrease fasting blood sugar levels by stimulating GLP-1 secretion and that intracellular DOP-induced GLP-1 secretion involved the Ca2+/calmodulin/CaMKII and MAPK pathways.


Asunto(s)
Dendrobium/química , Diabetes Mellitus Experimental/tratamiento farmacológico , Péptido 1 Similar al Glucagón , Hipoglucemiantes , Extractos Vegetales , Polisacáridos , Animales , Línea Celular , Péptido 1 Similar al Glucagón/sangre , Péptido 1 Similar al Glucagón/metabolismo , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Secreción de Insulina , Masculino , Ratones , Extractos Vegetales/química , Extractos Vegetales/farmacología , Polisacáridos/química , Polisacáridos/farmacología , Ratas , Ratas Sprague-Dawley
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