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•We have provided HAARTdrug combinations to PLWH for AIDS treatment in Huzhou, China. The free provided drugs included 3TC+EFV+TDF and drugs paid by patients included BIC+FTC+TAF.Free and paid drug combinations similarly increase CD4+ T-cell count and decrease VL.

Although Cu(II) ions bind to the prion protein (PrP), there have been conflicting findings concerning the number and location of binding sites. We have combined diethyl pyrocarbonate (DEPC)-mediated carbethoxylation, protease digestion, and mass spectrometric analysis of apo-PrP and copper-coordinated mouse PrP23–231 to “footprint” histidine-dependent Cu(II) coordination sites within this molecule. At pH 7.4 Cu(II) protected five histidine residues from DEPC modification. No protection was afforded by Ca(II), Mn(II), or Mg(II) ions, and only one or two residues were protected by Zn(II) or Ni(II) ions. Post-source decay mapping of DEPC-modified histidines pinpointed residues 60, 68, 76, and 84 within the four PHGGG/SWGQ octarepeat units and residue 95 within the related sequence GGGTHNQ. Besides defining a copper site within the protease-resistant core of PrP, our findings suggest application of DEPC footprinting methodologies to probe copper occupancy and pathogenesis-associated conformational changes in PrP purified from tissue samples.

While PrPCrearranges in the area of codons 104–113 to form PrPScduring prion infections, the events that initiate sporadic Creutzfeldt-Jakob disease are undefined. As Cu(II) is a putative ligand for PrPCand has been implicated in the pathogenesis of Creutzfeldt-Jakob disease and other neurodegenerative diseases, we investigated the structural effects of binding. Incubation of brain microsomes with Cu(II) generated ∼30-kDa proteinase K-resistant PrP. Cu(II) had little effect on fresh recombinant PrP23-231, but aged protein characterized by conversion of Asn-107 to Asp decreased α-helical content by ∼30%, increased β-sheet content 100%, formed aggregates, and acquired proteinase K resistance in the presence of Cu(II). These transitions took place without need for acid pH, organic solvents, denaturants, or reducing agents. Since conversion of Asn to Asp proceeds by a spontaneous pathway involving deamidation, our data suggest that covalent variants of PrPCarising in this manner may, in concert with Cu(II), generate PrPSc-like species capable of initiating sporadic prion disease.

The Mg2+-dependent serine/threonine protein phosphatases, also known as type 2C phosphatases (PP2C), belong to a gene family distinct from the other serine/threonine phosphatases and tyrosine phosphatases. Here we report the purification to apparent homogeneity of a novel Mg2+-dependent, Ca2+-inhibitable serine/threonine protein phosphatase from bovine brain. It is a type 2C enzyme in view of its Mg2+requirement, resistance to okadaic acid and calyculin A, inability to use phosphorylase aas substrate, and a segment of amino acid sequence typical of all PP2C type phosphatases known to date. However, it differs from the other PP2C enzymes, particularly the mammalian PP2Cα and -β isoforms, in that its molecular weight, 76,000, is considerably larger and that it is inhibited by Ca2+, NaF, and polycations, but not by orthovanadate. The Ca2+inhibition may not be related to its cellular regulation because of Kivalues in the 20-90 μM range, but this property permits distinction of this enzyme from the other phosphatases. Although the precise physiological role of this phosphatase is not yet known, its ability to dephosphorylate a wide variety of phosphoproteins and its broad distribution, as shown by a survey of mouse tissues for its activity, suggest that it may serve an important cellular function.