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Purpose: We aimed to evaluate whether [68 Ga]Ga-FAPI-04 PET/CT could characterize the early stages of cardiac fibrosis in pressure overload heart failure. Methods: Sprague–Dawley rats underwent abdominal aortic constriction (AAC) (n = 12) and sham surgery (n = 10). All rats were scanned with [68 Ga]Ga-FAPI-04 PET/CT at 2, 4, and 8 weeks after surgery. The expression of fibroblast activation protein (FAP) in the myocardium was detected by immunohistochemistry. [68 Ga]Ga-FAPI-04 PET signal and FAP expression were compared between two groups. Results: Compared with the sham group, the AAC group presented with decreased ejection fraction (EF) and fractional shortening (FS) and increased left ventricular internal dimensions in diastole (LVIDd) and systole (LVIDs) at 4 and 8 weeks (all p < 0.01). The AAC group showed higher [68 Ga]Ga-FAPI-04 accumulation in the heart than the sham group at 2, 4, and 8 weeks, and FAPI increased significantly from 2 to 8 weeks (all p < 0.001). Immunohistochemistry confirmed the higher density of the FAP+ area in the AAC group. The intensity of the [68 Ga]Ga-FAPI-04 correlated with the density of the FAP+ area (p < 0.001). The expression of the [68 Ga]Ga-FAPI-04 at 4 weeks correlated with the deterioration of cardiac function at 8 weeks (EF: R = − 0.87; FS: R = − 0.72; LVIDd: R = 0.77; LVIDs: R = 0.79; all p < 0.001). The AAC group also showed an increased [68 Ga]Ga-FAPI-04 signal in the liver, peaking at 4 weeks and then declining. Cardiac and liver PET signals correlated at 4 weeks in the AAC group (R = 0.69, p = 0.0010), suggesting an early fibrotic link between organs. A combination of the [68 Ga]Ga-FAPI-04 intensity in the heart and liver at 4 weeks better predicted the deterioration of cardiac function at 8 weeks. Conclusions: The activated fibroblasts in the heart and liver after pressure overload can be monitored by [68 Ga]Ga-FAPI-04 PET/CT, which reveals an early fibrotic link in cardio-liver interactions and could better predict nonischemic heart failure prognosis. [ABSTRACT FROM AUTHOR]

Two new cycloartane triterpenoid glycosides, soulieoside V (1) and 15-deacetylbeesioside O (2), together with one known compound, beesioside J (3), were isolated from the ethanolic extract of the rhizomes of Actaea vaginata. Their structures were elucidated by spectroscopic methods and by comparison with data reported in the literature. All the compounds were tested for their cytotoxic activities against human cancer cell lines. [ABSTRACT FROM AUTHOR]

The realization of efficient water electrolysis is still blocked by the requirement for a high and stable driving potential above thermodynamic requirements. An Ni-based electrocatalyst, is a promising alternative for noble-metal-free electrocatalysts but tuning its surface electronic structure and exposing more active sites are the critical challenges to improving its intrinsic catalytic activity. Here, we tackle the challenge by tuning surface electronic structures synergistically with interfacial chemistry and crystal facet engineering, successfully designing and synthesizing the carbon-encapsulated Ni (111)/Ni3C (113) heterojunction electrocatalyst, demonstrating superior hydrogen evolution reaction (HER) activities, good stabilities with a small overpotential of −29 mV at 10 mA/cm2, and a low Tafel slope of 59.96 mV/dec in alkaline surroundings, approximating a commercial Pt/C catalyst and outperforming other reported Ni-based catalysts. The heterostructure electrocatalyst operates at 1.55 V and 1.26 V to reach 10 and 1 mA cm−2 in two-electrode measurements for overall alkaline water splitting, corresponding to 79% and 98% electricity-to-fuel conversion efficiency with respect to the lower heating value of hydrogen. [ABSTRACT FROM AUTHOR]

Inactivation of sll0861 in Synechocystis sp. strain PCC 6803 or the homologous gene alr2432 in Anabaena sp. strain PCC 7120 had no effect on the growth of these organisms at a light intensity of 30 [micro]mol photons [m.sup.-2] [s.sup.-1] but reduced their growth at a light intensity of 5 or 10 [micro]mol photons [m.sup.-2] [s.sup.-1]. In Anabaena, inactivation of the gene also significantly reduced the rate of heterocyst differentiation under low-light conditions. The predicted products of sl10861 and alr2432 and homologs of these genes showed similarity to N-acetylmuramic acid 6-phosphate etherase (MurQ), an enzyme involved in peptidoglycan recycling, in Escherichia coli. E. coli murQ and the cyanobacterial homologs could functionally substitute for each other. We hypothesize that murQ in cyanobacteria promotes low-light adaptation through reutilization of peptidoglycan degradation products. doi: 10.1128/JB.01661-09

From the dried vines of Aspidopterys obcordata Hemsl, five new polyoxypregnane glycosides, named obcordatas J–N (1–5), were obtained. Their structures were fully elucidated and characterized by HRESIMS and extensive spectroscopic data. In addition, all of the new compounds were screened for their antinephrolithiasis activity in vitro. The results showed that compounds 1–3 have prominent protective effects on calcium oxalate crystal-induced human kidney 2 (HK-2) cells, with EC50 values ranging from 6.72 to 14.00 μM, which is consistent with the application value of A. obcordata in folk medicine for kidney stones. [ABSTRACT FROM AUTHOR]

Unlike Escherichia coli, the cyanobacterium Synechocystis sp. strain PCC 6803 is insensitive to chill (5[degree]C) in the dark but rapidly losses viability when exposed to chill in the light (100 [micro]mol photons [m.sup.-2] [s.sup.-l]). Preconditioning at a low temperature (15[degree]C) greatly enhances the chili-light tolerance of Synechocystis sp. strain PCC 6803. This phenomenon is called acquired chill-light tolerance (ACLT). Preconditioned wild-type cells maintained a substantially higher level of [alpha]-tocopherol after exposure to chill-light stress. Mutants unable to synthesize [alpha]-tocopherol, such as slr1736, slr1737, sir0089, and sir0090 mutants, almost completely lost ACLT. When exposed to chill without light, these mutants showed no or a slight difference from the wild type. When complemented, the sir0089 mutant regained its ACLT. Copper-regulated expression of sir0090 from [P.sub.petE] controlled the level of [alpha]-tocopherol and ACLT. We conclude that [alpha]-tocopherol is essential for ACLT of Synechocystis sp. strain PCC 6803. The role of [alpha]-tocopherol in ACLT may be based largely on a nonantioxidant activity that is not possessed by other tocopherols or pathway intermediates.