Sceloporus cautus

Number of Pages: 5Integrative BiologyGeological Science

Tetramethyl tert-butylcalix[4]arene tetraketone

The title molecule, 25,26,27,28-tetraacetonyloxy-5,11,- 17,23-tetra-tert-butylpentacyclo[19.3.1.13,7.19,13.115,19]- octacosa-1(25),3,5,7(28),9,11,13(27),15,17,19,21,23-dodecaene, has twofold crystallographic symmetry and adopts a distorted cone conformation in the solid state. The orientation of the four aromatic tings is such that two of the rings are almost parallel to each other and the other two almost normal to one another. This conformation precludes a solvent molecule being enclathrated within the cavity

O-H...π(arene) intermolecular hydrogen bonding in the structure of 1,1,2-triphenylethanol

The 1,1,2-triphenylethanol molecule, Ph2(PhCH2)COH (I), forms centrosymmetric dimers in the solid state. The shortest O-..O separation, 5.837 (3)A,, is too long for any O--H..-O hydrogen-bond formation. Instead, there are O--H~..π(arene) interactions between the hydroxyl group of one molecule and a phenyl group of a centrosymmetrically related molecule. The O...C and H-..C distances between the hydroxyl group and the closest phenyl-ring C atom are 3.525 (4) and 2.73 (4)~,, respectively. These intermolecular contacts are the only driving force towards dimer formation in the solid state

Hydrogen-bonding patterns in ferrocene derivatives: structures of 1,1'-diphenyl-1,1'-(1,1'-ferrocenediyl)diethanol and 1,1'-(1,1'-ferrocenediyl)diethanol

Racemic 1, l'-diphenyl- 1,1'-( 1, l'-ferrocenediyl)diethanol, [Fe{(CsH4)C(Ph)MeOH}2] (I), crystallizes as hydrogen- bonded dimeric aggregates with the Fe atoms on twofold crystallographic axes and the four O atoms defining a folded trapezium with O...O distances of 2.784 (2) (x2), 2.877(3) and 2.795 (4)A. The four hydroxyl H atoms are disordered equally over two orientations such that there are two half-occupancy H-atom sites between each hydrogen-bonded O-atom pair. Racemic 1,1'-(1, l'- ferrocenediyl)diethanol, [Fe{(CsH4)C(H)MeOH}2] (II),crystallizes as hydrogen-bonded centrosymmetric dimers, with O...O distances of 2.778 (2) and 2.764 (2) A and ordered hydroxyl H atoms. In (I), the dimers are formed from either two RR or two SS molecules, while in (II) the dimers each contain one RR and one SS molecule

Structures of 1-ferrocenyl-1-phenylethanol, ferrocenyl(diphenyl)methanol and ferrocene-1,1'-diylbis(diphenylmethanol)

Racemic 1-ferrocenyl- 1-phenylethanol, [(CsHs)Fe- (CsHa)]CPhMeOH (I), crystallizes as discrete molecules which are not involved in hydrogen bondinog; the shortest intermolecular O-..O contact is 3.768(3) A and the hydroxyl H atom is orientated towards the unsubstituted cyclopentadienyl ring. Ferrocenyl(diphenyl)methanol, [(CsHs)Fe(CsHa)]CPh2OH (II) is hydrogen bonded to form centrosynunetric dimers with O...O 2.816(1) and H...O 2.52 ]k. Ferrocene-l,l~-diylbis(diphenylmeth - anol), Fe[(CsHa)C(Ph)2COH]2 (III) crystallizes as a dimeric aggregate with the Fe atoms on twofold crystallographic symmetry axes and the four O atoms defining a folded trapezium with O...O 2.762(2), 2.714(2) and 2.865(2) A,. The four hydroxyl groups are disordered equally over two orientations such that there are two halfoccupancy H-atom sites between each hydrogen-bonded oxygen pair

C–H.I− interactions in ferrocene derivatives: structures of (Ferrocenylmethyl)triphenylphosphonium iodide and 1,1'-ferrocenediylbis(methyltriphenylphosphonium iodide) dichloromethane solvate (1/1)

The cations in (ferrocenylmethyl)triphenylphosphonium iodide, [{(C5H5)Fe(C5Ha)}CH2P(C6Hs)3]+.I -, (1), and in 1, l'-ferrocenediylbis(methyltriphenylphosphonium iodide) dichloromethane solvate, [Fe{(C5H4)CH2- P(C6H5)3}212+.2I-.CH2C12, (2), are involved in three dimensional networks of C--H. • .I- interactions between phenyl C--H groups and I- anions. In (1), the cation resides in a general position while one I- anion is on a twofold axis and a second I- anion is at an inversion centre. The shortest C...I- distances are 3.886 (2) and 3.989 (2)A to the I- ion which resides on an inversion centre. The cation in (2) has approximate mirror symmetry and lies in a general position in the unit cell along with its two I- anions. The shortest C--.I- interactions are 3.810 (4) and 3.886 (5) A,

Structures of tribenzylmethanol and 1,2,3-triphenyl-2-propanol

The tribenzylmethanol molecule, (PhCH2)3COH, has approximate threefold symmetry in the solid state. The hydroxyl H atom is disordered unequally over three orientations and is not involved in hydrogen bonding. The 1,2,3-triphenyl-2-propanol molecule, Ph(PhCH2)2COH, crystallizes with two molecules per asymmetric unit which differ slightly in conformation. In one of the molecules the hydroxyl H atom is disordered equally over two sites, whereas in the other molecule there is no disorder. As in the tribenzylmethanol molecule, there is no intermolecular O--H...O hydrogen bonding, presumably because of the steric bulk of the molecules and their packing which prevents the close approach of the O atoms of adjacent molecules

Positive Clinical Psychology and Schema Therapy (ST): the development of the Young Positive Schema Questionnaire (YPSQ) to complement the Young Schema Questionnaire 3 Short Form (YSQ-S3)

Negative schemas have been widely recognized as being linked to psychopathology and mental health, and they are central to the Schema Therapy (ST) model. This study is the first to report on the psychometric properties of the Young Positive Schema Questionnaire (YPSQ). In a combined community sample (Manila, Philippines, n = 559; Bangalore, India, n = 350; Singapore, n = 628), we identified a 56-item 14-factor solution for the YPSQ. Confirmatory factor analysis supported the 14-factor model for data from the Singapore sample as well as 2 other samples; an Eastern sample from Kuala Lumpur, Malaysia (n =229) and a Western sample from the United States (n = 214). Construct validity was demonstrated with the Young Schema Questionnaire 3 Short Form (YSQ-S3) that measures negative schemas and divergent validity was demonstrated for 11 of the YPSQ subscales with their respective negative schema counterparts. Convergent validity of the 14 subscales of YPSQ was demonstrated with measures of personality dispositions, emotional distress, well-being, trait gratitude, and humor styles. Positive schemas also showed incremental validity over and above negative schemas for these same measures thus demonstrating that both positive and negative schemas are separate constructs that relate in unique ways to mental health. Implications for using both the YPSQ and the YSQ-S3 scales in tandem in ST as well as cultural nuances from the use of Asian samples were discussed

Vacuolar and plasma membrane stripping and autophagic elimination of Toxoplasma gondii in primed effector macrophages

Apicomplexan protozoan pathogens avoid destruction and establish a replicative niche within host cells by forming a nonfusogenic parasitophorous vacuole (PV). Here we present evidence for lysosome-mediated degradation of Toxoplasma gondii after invasion of macrophages activated in vivo. Pathogen elimination was dependent on the interferon γ inducible-p47 GTPase, IGTP, required PI3K activity, and was preceded by PV membrane indentation, vesiculation, disruption, and, surprisingly, stripping of the parasite plasma membrane. Denuded parasites were enveloped in autophagosome-like vacuoles, which ultimately fused with lysosomes. These observations outline a series of mechanisms used by effector cells to redirect the fate of a classically nonfusogenic intracellular pathogen toward a path of immune elimination

Site-specific perturbations of alpha-synuclein fibril structure by the Parkinson's disease associated mutations A53T and E46K.

PMCID: PMC3591419This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Parkinson's disease (PD) is pathologically characterized by the presence of Lewy bodies (LBs) in dopaminergic neurons of the substantia nigra. These intracellular inclusions are largely composed of misfolded α-synuclein (AS), a neuronal protein that is abundant in the vertebrate brain. Point mutations in AS are associated with rare, early-onset forms of PD, although aggregation of the wild-type (WT) protein is observed in the more common sporadic forms of the disease. Here, we employed multidimensional solid-state NMR experiments to assess A53T and E46K mutant fibrils, in comparison to our recent description of WT AS fibrils. We made de novo chemical shift assignments for the mutants, and used these chemical shifts to empirically determine secondary structures. We observe significant perturbations in secondary structure throughout the fibril core for the E46K fibril, while the A53T fibril exhibits more localized perturbations near the mutation site. Overall, these results demonstrate that the secondary structure of A53T has some small differences from the WT and the secondary structure of E46K has significant differences, which may alter the overall structural arrangement of the fibrils