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Ultrathin flexible organic solar cells (OSCs) have garnered widespread attention in wearable electronic devices for their lightweight and excellent conformability. Silver nanowires (AgNWs) are one of the most widely used bottom electrodes because of their high conductivity and transmittance. However, the high roughness of AgNWs on the flexible substrate exerts adverse effects on device performance. To address this critical issue, a bilayer electron‐transport‐materials (ETMs) strategy consisting of an indium‐doped zinc oxide (IZO) and a pristine ZnO is developed. The IZO is utilized as the first layer of ETM, which can effectively fill voids in AgNWs to form a high‐conductive composite electrode. The ZnO is used as the second layer of ETM, facilitating charge extraction. The ultrathin flexible OSCs prepared based on the gradient bilayer ETMs can achieve a power conversion efficiency (PCE) of 16.1%, associated with improved mechanical stability, showing a PCE retention of 93% after 10 000 bending cycles (R = 1 mm) and 82% under 1000 compression (30%)‐release cycling test. To the best of knowledge, it's one of the highest efficiency for ultrathin (less than 10 μm) flexible OSCs based on the solution‐processed electrodes. This work will provide a new avenue for fabricating high‐performance and mechanically robust ultraflexible ITO‐free OSCs. [ABSTRACT FROM AUTHOR]

Macrophages are the major tumor-infiltrating leukocytes, and tumor-associated macrophages (TAM) play a critical role in cancer-related inflammation since they show alternative polarization to M1 (tumor-inhibited macrophages) or M2 (tumor-promoted macrophages) phenotype. Brassica rapa L. (B. rapa) has been clinically proven to have anti-tumor and immunity-enhancing activity, and the polysaccharides of B. rapa (BRP) have been reported to have an immunoregulatory effect on macrophages. In this study, we focus on macrophage polarization to investigate the mechanism of anti-tumor response of BRP in vivo and in vitro. We found that BRP improved the expression of M1 markers, including iNOS, COX-2, HLA-DR, CD11b and M1-related cytokines. The expression of M2 markers Arg-1, CD206 and CD163 induced by IL-4 were inhibited by BRP treatment, resulting in the inhibition of tumor growth both in vivo and in co-culture experiments in vitro. The activation of STAT signaling pathway were significantly regulated by BRP, which are important signals in TAM polarization. Overall, the results indicated that BRP has anti-tumor effect through mediating macrophage polarization. [ABSTRACT FROM AUTHOR]

Oxidation of a thiophene‐hexapyrrane hybrid S‐P6 afforded a stable conjugated open‐chain thiaheptapyrrolic helix 1 with the terminal thiophene and confused pyrrole units lying at a long distance that is adverse for further cyclization. Chelation of 1 with copper(II) ion afforded 1‐Cu, which exhibits more distant terminal units. Interestingly, further oxidation of 1 triggered an intramolecular C−N fusion reaction to afford a unique 5,5,5‐tricyclic fused linear thiaheptapyrrin 2, with the two terminals positioned in proximity, which favors the oxidative ring‐closure reaction to give a unique 5,5,5‐tricyclic fused thiaheptaphyrin (1.1.1.1.1.1.0) 3 under air. The inner‐fusion strategy for positioning the reactive sites in proximity to promote oxidative cyclization offers a new approach for constructing large porphyrinoids through conjugated oligopyrrins without the assistance of metal ions. [ABSTRACT FROM AUTHOR]

In senescent leaves chlorophyll (Chl) catabolites typically accumulate as colorless tetrapyrroles, classified as formyloxobilin‐type (or type‐I) or dioxobilin‐type (type‐II) phyllobilins (PBs). Yellow type‐I Chl catabolites (YCCs) also occur in some senescent leaves, in which they are generated by oxidation of colorless type‐I PBs. A yellow type‐II PB was recently proposed to occur in extracts of fall leaves of grapevine (Vitis vinifera), tentatively identified by its mass and UV/Vis absorption characteristics. Here, the first synthesis of a yellow type‐II Chl catabolite (DYCC) from its presumed natural colorless type‐II precursor is reported. A homogenate of a Spatiphyllum wallisii leaf was used as "green" means of effective and selective oxidation. The synthetic DYCC was fully characterized and identified with the yellow grapevine leaf pigment. As related yellow type‐I PBs do, the DYCC functions as a reversible photoswitch by undergoing selective photo‐induced Z/E isomerization of its C15=C16 bond. A new type of a yellow chlorophyll catabolite, provisionally identified in senescent grapevine leaves, was prepared from its hypothetical natural colorless precursor and characterized as a yellow type‐II phyllobilin. The elementary photochemical behavior of this new bilirubin‐like tetrapyrrole was explored, revealing a reversible photoinduced Z/E isomerization, a common basic feature, apparently, of the yellow chlorophyll catabolites and of other bilin‐type natural products. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) is a refractory malignant tumor with poor prognosis, limited chemotherapeutic efficacy, and only about 5% of 5‐year survival rate. We generated a dual‐targeting ligand‐based lidamycin (DTLL) to investigate its efficacy against pancreatic cancer after preparing its precursor, DTLP. DTLP was shown specifically binding to EGFR and HER2 on cell surface, followed by endocytosis into cytoplasm of pancreatic cancer cells. DTLL significantly promoted apoptosis and cell cycle arrest at G2/M stages and inhibited cell proliferation. Pancreatic tumors of either MIA‐paca‐2 cell line‐derived (CDX) or patient‐derived xenograft (PDX) mouse models were significantly regressed in response to DTLL. It suggested that DTLL might be a highly potent bispecific antibody‐drug conjugate (ADC)‐like agent for pancreatic cancer therapy. LDM is known to function as an antitumor cytotoxic agent by its induction of DNA damage in cancer cells, therefore, DTLL, as its derivative, also showed similar cytotoxicity. However, we found that DTLL might reverse the AKT/mTOR feedback activation induced by LDM at the first time. The results from both in vitro and in vivo experiments suggested that DTLL enhanced DNA damage via EGFR/HER2‐dependent blockage of PI3K/AKT/mTOR and PD‐L1 signaling pathways in cancer cells, leading to the inhibition of cell proliferation and immunosurveillance escape from pancreatic tumor. Our studies on DTLL functional characterization revealed its novel mechanisms on internal enhancement of DNA damage and implied that DTLL might provide a promising targeted therapeutic strategy for pancreatic cancer. DTLP showed bispecific binding activities to EGFR/HER‐2 in vitro and in vivo. DTLL showed potent anti‐pancreatic cancer efficacy in CDX and PDX mouse models of human pancreatic cancer 3. DTLL had an antineoplastic effect by inhibited AKT/mTOR and PD‐1/PD‐L1 signal pathways in human pancreatic cancer. [ABSTRACT FROM AUTHOR]

The tetrapyrrolic chlorophyll catabolites (or phyllobilins, PBs) were analyzed in yellow fall leaves of the grape Chardonnay, a common Vitis vinifera white wine cultivar. The major fractions in leaf extracts of V. vinifera, tentatively assigned to PBs, were isolated and their structures elucidated. The dominant fraction is a dioxobilin‐type non‐fluorescent Chl‐catabolite of a previously observed type. Two less polar fluorescent PBs were characterized as a novel dioxobilin‐type fluorescent Chl‐catabolite with a bicyclo‐1′,6′‐glycosyl architecture, and its new fluorescent formyloxobilin‐type analogue. The discovery of persistent hypermodified fluorescent PBs with the architecture of bicyclo‐[17.3.1]‐PBs (bcPBs), suggests the activity of an unknown enzyme that forges the 20‐membered macroring at the tetrapyrrolic core of a fluorescent PB. bcPBs may play specific physiological roles in grapevine plants and represent endogenous anti‐infective agents, as found similarly for other organic bicyclo‐[n.3.1]‐1′,6′‐glycosyl derivatives. The colors of the fall: Blue fluorescent chlorophyll catabolites with a unique bicyclo‐1′,6′‐glycosyl architecture occur in golden yellow fall leaves of Chardonnay, a common white wine cultivar. This discovery implies unknown enzymes that assemble a 20‐membered macroring at a tetrapyrrole to generate exceptionally structured chlorophyll catabolites. Possibly, these may play specific physiological roles and/or represent anti‐infective agents in the grapevine leaves. [ABSTRACT FROM AUTHOR]

In senescent leaves, chlorophyll typically is broken down to colorless and essentially photo-inactive phyllobilanes, which are linear tetrapyrroles classified as "nonfluorescent" chlorophyll catabolites (NCCs) and dioxobilane-type NCCs (DNCCs). In homogenates of senescent leaves of the tropical evergreen Spathiphyllum wallisii, when left at room temperature and extracted with methanol, the major endogenous, naturally formed NCC was regio- and stereoselectively oxidized (in part) to a mixture of its 15-hydroxy and 15-methoxy derivative. In the absence of methanol in the extract, only the 15-OH-NCC was observed. The endogenous oxidation process depended upon molecular oxygen. It was inhibited by carbon monoxide, as well as by keeping the leaf homogenate and extract at low temperatures. The remarkable "oxidative activity" was inactivated by heating the homogenate for 10 min at 70°C. Upon addition of a natural epimeric NCC (epiNCC) to the homogenate of senescent or green Sp. wallisii leaves at room temperature, the exogenous epiNCC was oxidized regio- and stereoselectively to 15-OHepiNCC and 15-OMe-epiNCC. The identical two oxidized epiNCCs were also obtained as products of the oxidation of epiNCC with dicyanodichlorobenzoquinone (DDQ). Water elimination from 15-OH-epiNCC occurred readily and gave a known "yellow" chlorophyll catabolite (YCC). The endogenous oxidation process, described here, may represent the elusive natural path from the colorless NCCs to yellow and pink coloured phyllobilins, which were found in (extracts of) some senescent leaves. [ABSTRACT FROM AUTHOR]

Aim This study investigated the clinical characteristics of internet addiction using a cross-sectional survey and psychiatric interview. Methods A structured questionnaire consisted of demographics, Symptom Checklist 90, Self-Rating Anxiety Scale, Self-Rating Depression Scale, and Young's Internet Addiction Test ( YIAT) was administered to students of two secondary schools in Wuhan, China. Students with a score of 5 or higher on the YIAT were classified as having Internet Addiction Disorder ( IAD). Two psychiatrists interviewed students with IAD to confirm the diagnosis and evaluate their clinical characteristics. Results Of a total of 1076 respondents (mean age 15.4 ± 1.7 years; 54.1% boys), 12.6% ( n = 136) met the YIAT criteria for IAD. Clinical interviews ascertained the Internet addiction of 136 pupils and also identified 20 students (14.7% of IAD group) with comorbid psychiatric disorders. Results from multinomial logistic regression indicated that being male, in grade 7-9, poor relationship between parents and higher self-reported depression scores were significantly associated with the diagnosis of IAD. Conclusion These results advance our understanding of the clinical characteristics of Internet addiction in Chinese secondary school students and may help clinicians, teachers, and other stakeholders better manage this increasingly serious mental condition. [ABSTRACT FROM AUTHOR]

In the title complex, [PdBr(2)(C(13)H(18)N(2))(2)], the Pd(II) atom is situated on an inversion center. The tetra-hydro-pyrimidine group of the N-(2,4,6-trimethyl-phen-yl)-1,4,5,6-tetra-hydro-pyrimidine ligand is twisted from the square (PdN(2)Br(2)) coordination plane with a C-N-Pd-Br torsion angle of 81.8 (4)°; this is different from the angle of 43.47 (14)°, reported in a closely related structure, dichloridobis(1-methyl-1,4,5,6-tetra-hydro-pyrimidine)-palladium(II).