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A linear correlation of chemical shifts (δ) of signals in the 13C NMR spectra of the unsubstituted terminal carbon atom of the allyl ligand in [(1-R-η3-C3H4)Pd]NO3 (R = Me, CH2OMe, CO2Me, COMe, CHO) with the substituent constants σ+ and σs- in acetone solutions was found. A considerable deviation from linearity was observed for R = Ph. The 13C nuclear magnetic screening constants were calculated by the DFT method in the GIAO approximation for equilibrium geometries of the cations [(1-R-η3-C3H4)Pd(Me2C=0)2]+ and anions [(1-R-η3-C3H4)PdCl2]s-. In the latter case, the theoretical and experimental δ values are consistent. The influence of the substituent R on the geometric parameters and charges on atoms in the neutral, anionic, and cationic η3-allylpalladium complexes is discussed. [ABSTRACT FROM AUTHOR]

Introduction: Low sexual desire is a frequent sexual problem in women, with only one drug for the condition approved by the Food and Drug Administration., Aim: To evaluate the ability of a novel synthetic peptide, BP101, to facilitate sexual behavior after intranasal administration or infusion into certain brain areas in female rats., Methods: Bilaterally ovariectomized female rats, primed with a suboptimal combination of estradiol benzoate (EB) and progesterone, were used as a model of low sexual motivation. Sexual behavior was tested with stud male rats after acute (experiment 1) or long-term (experiment 2) intranasal administration of BP101 or peptide infusion into the olfactory bulb, medial preoptic area, ventromedial hypothalamic nucleus, or ventral tegmental area (experiment 3)., Main Outcome Measures: Frequency of solicitations (SF), as an indicator of sexual motivation in female rats, and lordosis frequency and ratio, as measurements of female consummatory sexual behavior., Results: Acute intranasal BP101 administration moderately increased SF, with the highest tested dose of 300 μg/kg causing an 80% increase. Female rats receiving BP101 75 or 300 μg/kg daily on days 6 to 16 of the peptide administration displayed twofold higher SF compared with the placebo-treated animals, an increase comparable to optimally hormone-primed female rats. Infusion of BP101 1 and 5 μg per rat into the medial preoptic area, but not into the olfactory bulb, ventromedial hypothalamic nucleus, or ventral tegmental area, increased SF in female rats supplemented with EB 10 or 20 μg. The effect was relatively more pronounced in female rats receiving EB 10 μg (≈300%) compared with EB 20 μg (≈50%) with direct brain infusions., Conclusion: BP101 displays a potent stimulatory effect on sexual motivation in the female rat, and the medial preoptic area seems to be the site of its action. BP101 is effective in female rats receiving different hormone supplementations, making the present data generalizable to pre- and postmenopausal women with hypoactive sexual desire. Andreev-Andrievskiy A, Lomonosov M, Popova A, et al. BP101 Peptide Promotes Female Sexual Receptivity in the Rat. J Sex Med 2017;14:336-346., (Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.)

Fbxo7 is an unusual F-box protein because most of its interacting proteins are not substrates for ubiquitin-mediated degradation. Fbxo7 directly binds p27 and Cdk6, enhances the level of cyclin D-Cdk6 complexes, and its overexpression causes Cdk6-dependent transformation of immortalised fibroblasts. Here, we test the ability of Fbxo7 to transform haematopoietic pro-B (Ba/F3) cells which, unexpectedly, it was unable to do despite high levels of Cdk6. Instead, reduction of Fbxo7 expression increased proliferation, decreased cell size and shortened G1 phase. Analysis of cell cycle regulators showed that cells had decreased levels of p27, and increased levels of S phase cyclins and Cdk2 activity. Also, Fbxo7 protein levels correlated inversely with those of CD43, suggesting direct regulation of its expression and, therefore, of B cell maturation. Alterations to Cdk6 protein levels did not affect the cell cycle, indicating that Cdk6 is neither rate-limiting nor essential in Ba/F3 cells; however, decreased expression of Cdk6 also enhanced levels of CD43, indicating that expression of CD43 is independent of cell cycle regulation. The physiological effect of reduced levels of Fbxo7 was assessed by creating a transgenic mouse with a LacZ insertion into the Fbxo7 locus. Homozygous Fbxo7(LacZ) mice showed significantly increased pro-B cell and pro-erythroblast populations, consistent with Fbxo7 having an anti-proliferative function and/or a role in promoting maturation of precursor cells.

Fbxo7 is an unusual F box protein that augments D-type cyclin complex formation with Cdk6, but not Cdk4 or Cdk2, and its over-expression has been demonstrated to transform immortalised fibroblasts in a Cdk6-dependent manner. Here we present new evidence in vitro and in vivo on the oncogenic potential of this regulatory protein in primary haematopoietic stem and progenitor cells (HSPCs). Increasing Fbxo7 expression in HSPCs suppressed their colony forming ability in vitro, specifically decreasing CD11b (Mac1) expression, and these effects were dependent on an intact p53 pathway. Furthermore, increased Fbxo7 levels enhanced the proliferative capacity of p53 null HSPCs when they were grown in reduced concentrations of stem cell factor. Finally, irradiated mice reconstituted with p53 null, but not wild-type, HSPCs expressing Fbxo7 showed a statistically significant increase in the incidence of T cell lymphoma in vivo. These data argue that Fbxo7 negatively regulates the proliferation and differentiation of HSPCs in a p53-dependent manner, and that in the absence of p53, Fbxo7 expression can promote T cell lymphomagenesis.

F-box proteins are the substrate-recognition components of the Skp1-Cul1-F box protein (SCF) E3 ubiquitin ligases. Here we report a structural relationship between Fbxo7, a component of the SCF(Fbxo7) E3 ligase, and the proteasome inhibitor PI31. SCF(Fbxo7) is known to catalyze the ubiquitination of hepatoma-up-regulated protein (HURP) and the inhibitor of apoptosis (IAP) protein but also functions as an activator of cyclin D-Cdk6 complexes. We identify PI31 as an Fbxo7.Skp1 binding partner and show that this interaction requires an N-terminal domain present in both proteins that we term the FP (Fbxo7/PI31) domain. The crystal structure of the PI31 FP domain reveals a novel alpha/beta-fold. Biophysical and mutational analyses are used to map regions of the PI31 FP domain mediating homodimerization and required for heterodimerization with Fbxo7.Skp1. Equivalent mutations in Fbxo7 ablate interaction with PI31 and also block Fbxo7 homodimerization. Knockdown of Fbxo7 does not affect PI31 levels arguing against PI31 being a substrate for SCF(Fbxo7). We present a model for FP domain-mediated dimerization of SCF(Fbxo7) and PI31.

How dividing mammalian cells overcome blocks to DNA replication by DNA damage, depleted nucleotide pools, or template-bound proteins is unclear. Here, we show that the response to blocked replication requires BRCA2, a suppressor of human breast cancer. By using two-dimensional gel electrophoresis, we demonstrate that Y-shaped DNA junctions at stalled replication forks disappear during genome-wide replication arrest in BRCA2-deficient cells, accompanied by double-strand DNA breakage. But activation of the replication checkpoint kinase Chk2 is unaffected, defining an unexpected function for BRCA2 in stabilizing DNA structures at stalled forks. We propose that in BRCA2 deficiency and related chromosomal instability diseases, the breakdown of replication forks, which arrest or pause during normal cell growth, triggers spontaneous DNA breakage, leading to mutability and cancer predisposition.

PCR is a highly sensitive, convenient and rapid method for detection of viral DNA in fixed tissue samples which allows one to analyse the material from the pathology files, mainly biopsies. PCR in a fixed material requires larger amounts of DNA-polymerase and longer duration of every stage of thermo-cycles compared to PCR in the purified DNA samples.

Intrinsic tissue calcification mainly results from increased penetration of plasma proteins into the leaflets of bioprosthetic cardiac valves. The loss of activity of natural calcification inhibitors changes tissue properties and promotes pathological processes. N-vinylpyrrolidone, 3-amino-1,1-hydroxypropylendiphosphonic acid, O,O-diethylvinylphosphonates and antiaggregant (acryloilsalicylic acid) were used to decrease porosity and prevent calcification. gamma-radiation and glutaraldehyde were used to immobilize these agents. Tissue calcification was studied using subcutaneous implantation of the samples in young rats. The study indicates that the copolymerization of N-vinylpyrrolidone, O,O-diethylvinylphosphonates and acryloilsalicylic acid decreases calcium and phosphorous accumulation during in vivo experiments.