Molybdenum disulfide (MoS2) is an emerging material with some unique physical and electronic properties somewhat comparable to those of graphene. It was prepared with the use of a simple hydrothermal process, and has a layered structure similar to that of graphene. Also, it has a peroxidase-like catalytic activity and is able to catalyze the oxidation of the colorless peroxidase substrate, 3,3',5,5'-tetramethylbenzidine (TMB), in the presence of H2O2 to produce a blue product. This reaction used MoS2 as a useful peroxidase, which involved a colorimetric method for trace analysis of H2O2 in water, e.g. lake waters. This method is uncomplicated, inexpensive and highly sensitive for H2O2 in the 0.125-1.75 μM range (LOD: 0.08 μM). It is also quite stable in the presence of many common inorganic and organic potentially interfering compounds, e.g. metal ions as well as amino acids and sugars.

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Our data indicate a strong association between the 3-pos and renal disease activities, especially proliferative glomerulonephritis. The ability of 3-pos to predict renal flares may lead to major additional benefits in the follow-up of these patients.

A simple chemical oxidation and ultrasound exfoliation method has been developed to synthesize the two-dimensional and ultrathin-layer materials-graphitic carbon nitride nanosheets (g-CN NNs). The prepared ultrathin g-CN NNs display strong fluorescence and stability, including good photostability and excellent antisalt ability. Herein, a new "on-off-on" fluorescent switching sensor is designed. The iron ion (Fe) has an ultrasensitive response to quench the fluorescence of g-CN NNs based on the synergistic effect between inner filter effect and photoinduced electron transfer. The linear limit for Fe was from 0.05 to 30 μmol L with a detection limit of 0.018 μmol L. Meanwhile, the fluorescence of g-CN NNs can recover through the redox reaction between Fe and ascorbic acid (AA). In addition, the linear range for AA was from 0.2 to 112.5 μmol L with a 0.086 μmol L detection limit. The proposed method exhibited rapid response, excellent selectivity, wide detection range, and low detection limit for simultaneous analysis of Fe and AA, and it was applied for the determination of Fe and AA in water sample and human serum with satisfactory results.

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Metabolite-protein interactions (MPIs) play key roles in cancer metabolism. However, our current knowledge about MPIs in cancers remains limited due to the complexity of cancer cells. Herein, the authors construct an integrative MPI network and propose a MPI network based hepatocellular carcinoma (HCC) subtyping and mechanism exploration workflow. Based on the expressions of hub proteins on the MPI network, two prognosis-distinctive HCC subtypes are identified. Meanwhile, multiple interdependent features of the poor prognostic subtype are observed, including hypoxia, DNA hypermethylation of metabolic pathways, fatty acid accumulation, immune pathway up-regulation, and exhausted T-cell infiltration. Notably, the immune pathway up-regulation is probably induced by accumulated unsaturated fatty acids which are predicted to interact with multiple immune regulators like SRC and TGFB1. Moreover, based on tumor microenvironment compositions, the poor prognostic subtype is further divided into two sub-populations showing remarkable differences in metabolism. The subtyping shows a strong consistency across multiple HCC cohorts including early-stage HCC. Overall, the authors redefine robust HCC prognosis subtypes and identify potential MPIs linking metabolism to immune regulations, thus promoting understanding and clinical applications about HCC metabolism heterogeneity.

Nonclassical antifolates, 2,4-diamino-5-substituted-furo[2, 3-d]pyrimidines 3-12 with bridge region variations of C8-S9, C8-N9, and C8-O9 and 1-naphthyl, 2-naphthyl, 2-phenoxyphenyl, 4-phenoxyphenyl, and 2-biphenyl side chains were synthesized as phenyl ring appended analogues of previously reported 2, 4-diamino-5-(anilinomethyl)furo[2,3-d]pyrimidines. The phenyl ring appended analogues were designed to specifically interact with Phe69 of dihydrofolate reductase (DHFR) from Pneumocystis carinii (pc) to afford selective inhibitors of pcDHFR. Additional substituted phenyl side chains which include 2,5-dichloro, 3,4-dichloro, 3,4,5-trichloro, 3-methoxy, and 2,5-dimethoxy analogues 13-17 were also synthesized. The compounds were prepared by nucleophilic displacement of 2,4-diamino-5-(chloromethyl)furo[2,3-d]pyrimidine(2) with the appropriate thiol, amine, or naphthol. Compound 2 was obtained from 2,4-diamino-6-hydroxypyrimidine and 1, 3-dichloroacetone. The compounds were evaluated as inhibitors against DHFR from P. carinii, Toxoplasma gondii, and rat liver. Two analogues, 2,4-diamino-5-[(2'-naphthylthio)methyl]furo[2, 3-d]pyrimidine (5) and 2,4-diamino-5-[(2'-phenylanilino)methyl]furo[2,3-d]pyrimidine (11) showed significant selectivity and potency for pcDHFR compared to trimethoprim. The X-ray crystal structure of 5 with pcDHFR was also carried out, which corroborated the design rationale and indicated a hydrophobic interaction of the naphthalene ring of 5 and Phe69 of pcDHFR which is responsible, in part, for the more than 18-fold selectivity of 5 for pcDHFR as compared with rat liver DHFR.

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