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Purpose: We examined the association between catheter use for maintenance hemodialysis (HD) and mortality/hospitalization in a cohort of patients with prevalent HD.Methods: In this study, 70 HD patients with tunneled cuffed central venous catheters (TCVCs) from a Taiwanese HD center during 2014-2016 were enrolled and compared with 70 matched HD patients with native arteriovenous fistulae (AVF). The compared variables included demographic parameters and laboratory and dialysis-related indices. Cox regression analysis was used to assess the risk of mortality/hospitalization within a year.Results: Low baseline serum albumin levels were found in patients with TCVCs (3.64 g/dL vs 3.79 g/dL, p = 0.030). The mortality rates of patients with AVF and TCVCs were 14 per 1000 patients and 171 per 1000 patients, respectively. Infection was the leading cause of mortality/hospitalization in patients with TCVCs. Using multivariate analyses, the risk of death was found to be significantly higher in patients with TCVCs than in those with AVF (Hazard ratio [HR] 12.15, 95% CI 1.16-127.17; p = 0.037). Patients with TCVC also had a higher hospitalization rate (HR 1.33, 95% CI 0.71-2.49; p = 0.369) (not statistically significant).Conclusion: Catheter use for maintenance HD was associated with increased all-cause mortality. [ABSTRACT FROM AUTHOR]

Two experimentally well characterized four-coordinate complexes of the general formula [Co(2-NCH 2 - p -C 6 H 4 CH 3 -21- m -CH 2 C 6 H 4 CH 3 NCTPP)L] (with L = Cl − and N*CS − for 3 and 4 ) are considered for this study. The crystal structures of the paramagnetic chloro(2-aza-2-[ p -methyl benzyl]-5,10,15,20-tetraphenyl-21- m -xylyl-21-carbaporphyrinato-N,N′,N″) cobalt(II) octane solvate [Co(2-NCH 2 - p -C 6 H 4 CH 3 -21- m -CH 2 C 6 H 4 CH 3 NCTPP)Cl]·0.5C 8 H 18 ( 3 ·0.5 C 8 H 18 ) and thiocyanato-N-(2-aza-2-[ p -methylbenzyl]-5,10,15,20-tetraphenyl-21- m -xylyl-21-carbaporphyrinato-N,N′,N″) cobalt(II) [Co(2-NCH 2 - p -C 6 H 4 CH 3 -21- m -CH 2 C 6 H 4 CH 3 NCTPP)(NCS)] ( 4 ) were established. The geometry around the Co 2+ ion in 3 ·0.5 C 8 H 18 (or 4 ) is a distorted tetrahedron, with C 2v symmetry. The magnitude of the zero-field splitting (ZFS) parameter (D) was reported to change from 44.5 cm −1 in 3 to 30.0 cm −1 in 4 through DC magnetic susceptibility determinations. The | D | value can be related to the magnitude of the ligand-field splitting parameter of the axial k-donating Cl − ligand of 3 and the axial π-accepting NCS − ligand of 4 at the cobalt sites. [ABSTRACT FROM AUTHOR]

The crystal structures of 2-aza-2-[ p -(isopropyl)benzyl]-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N′,N″)palladium(II) [Pd (2-NCH 2 - p -C 6 H 4 -isoC 3 H 7 NCTPP); 3 ], (2-azo-2-[ p -(isopropyl)]-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N′,N″)platinum(II) [Pt(2-NCH 2 - p -C 6 H 4 -isoC 3 H 7 NCTPP); 4 ], iodo(2-azo-2-[ p -(isopropyl)benzyl]-5,10,15,20-tetraphenyl-21-hydrogen-21-carbaporphyrinato-N,N′,N″)mercury(II) toluene solvate [Hg(2-NCH 2 - p -C 6 H 4 -isoC 3 H 7 -21-H-NCTPP)I⋅C 6 H 5 CH 3 ; 5 ⋅C 6 H 5 CH 3 ], (2-azo-2-[ p -methylbenzyl]-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N′,N″)nickel(II) [Ni(2-NCH 2 - p -C 6 H 4 -CH 3 NCTPP); 6 ] and iodo(2-azo-2-[ p -methylbenzyl]-5,10,15,20-tetraphenyl-21-hydrogen-21-carbaporphyrinato-N,N′,N″)mercury(II) [Hg(2-NCH 2 - p -C 6 H 4 -CH 3 -21-H-NCTPP)I; 7 ] were determined. The coordination sphere around the Pd 2+ (or Pt 2+ , Ni 2+ ) ion in 3 (or 4 , 6 ) is distorted square planar (DSP) whereas for Hg 2+ in 5 (or 7 ), it is a distorted tetrahedral complex with the T-based pyramid of the C 2v symmetry. The coupling of H(17) in 5 ( 7 ) to 199 Hg with J [ 199 Hg–H(17)] = 34.8 Hz ( 5 ) and J [ 199 Hg–H(17)] = 34.2 Hz ( 7 ), supported the assignment of agostic η 2 –C–H(17)⋯Hg interactions in these two mercury complexes. [ABSTRACT FROM AUTHOR]

Piezoelectric energy harvesting is a promising technique for scavenging ambient mechanical motion for driving compact, low-power, multi-functional electronic devices. To adapt to various ambient surroundings, the geometric configurations and sizes varied in wide ranges with high operational reliabilities and piezoelectric performance have been regarded as a key for piezoelectric harvester design. Herein, by applying a normal force, we report an innovative structure for harvesting electric energy from bending the obliquely aligned GaN piezoelectric nanorods (NRs) that are integrated in the vertically integrated nanogenerator (VING). The single-crystalline GaN NRs used here were successfully synthesized with obliquely alignments on the pyramided Si substrate by plasma-assisted molecular beam epitaxy (PA-MBE). Using conductive atomic force microscope (c-AFM), a remarkable change in the Schottky barrier height (SBH) between the tip and GaN NR is observed upon bending an oblique-aligned GaN NR. This demonstrates that a remarkably enhanced piezoelectric performance of GaN NRs can be achieved by coupling a lateral force. We anticipate that this work will provide an efficient approach for coupling the lateral loading to enhance the electric potential in piezoelectric NRs-embedded VING, and thus open a new path for efficiently generating electric energy. [ABSTRACT FROM AUTHOR]

Cytoplasmic Ca2+ oscillations constitute a widespread signaling mode and are often generated in response to stimulation of G protein-coupled receptors that activate phospholipase C. In mast cells, repetitive Ca2+ oscillations can be evoked by modest activation of cysteinyl leukotriene type I receptors by the physiological trigger, leukotriene C4. The Ca2+ oscillations arise from regenerative Ca2+ release from inositol 1,4,5-trisphosphate-sensitive stores followed by Ca2+ entry through store-operated Ca2+ channels, and the latter selectively activate the Ca2+-dependent transcription factor NFAT. The cysteinyl leukotriene type I receptors desensitize through negative feedback by protein kinase C, which terminates the oscillatory Ca2+ response. Here, we show that the scaffolding protein caveolin-1 has a profound effect on receptor-driven Ca2+ signals and downstream gene expression. Overexpression of caveolin-1 increased receptor-phospholipase C coupling, resulting in initially larger Ca2+ release transients of longer duration but which then ran down quickly. NFAT-activated gene expression, triggered in response to the Ca2+ signal, was also reduced by caveolin-1. Mutagenesis studies revealed that these effects required a functional scaffolding domain within caveolin-1. Mechanistically, the increase in Ca2+release in the presence of caveolin-1 activated protein kinase C, which accelerated homologous desensitization of the leukotriene receptor and thereby terminated the oscillatory Ca2+ response. Our results reveal that caveolin-1 is a bimodal regulator of receptor-dependent Ca2+ signaling, which fine-tunes the spatial and temporal profile of the Ca2+ rise and thereby its ability to activate the NFAT pathway. [ABSTRACT FROM AUTHOR]

Objective: The aims of this cross-sectional study were to examine the associations of suicidal ideation and attempt with Internet addiction and Internet activities in a large representative Taiwanese adolescent population. Methods: 9510 adolescent students aged 12-18 years were selected using a stratified random sampling strategy in southern Taiwan and completed the questionnaires. The five questions from the Kiddie Schedule for Affective Disorders and Schizophrenia were used to inquire as to the participants' suicidal ideation and attempt in the past one month. The Chen Internet Addiction Scale was used to assess participants' Internet addiction. The kinds of Internet activities that the adolescents participated in were also recorded. The associations of suicidal ideation and attempt with Internet addiction and Internet activities were examined using logistic regression analysis to control for the effects of demographic characteristics, depression, family support and self-esteem. Results: After controlling for the effects of demographic characteristics, depression, family support and self-esteem, Internet addiction was significantly associated with suicidal ideation and suicidal attempt. Online gaming, MSN, online searching for information, and online studying were associated with an increased risk of suicidal ideation. While online gaming, chatting, watching movies, shopping, and gambling were associated with an increased risk of suicidal attempt, watching online news was associated with a reduced risk of suicidal attempt. Conclusions: The results of this study indicated that adolescents with Internet addiction have higher risks of suicidal ideation and attempt than those without. Meanwhile, different kinds of Internet activities have various associations with the risks of suicidal ideation and attempt. [ABSTRACT FROM AUTHOR]

Background: Suicidal ideation and attempt among adolescents are risk factors for eventual completed suicide. Cellular phone use (CPU) has markedly changed the everyday lives of adolescents. Issues about how cellular phone use relates to adolescent mental health, such as suicidal ideation and attempts, are important because of the high rate of cellular phone usage among children in that age group. This study explored the association between problematic CPU and suicidal ideation and attempts among adolescents and investigated how family function and depression influence the association between problematic CPU and suicidal ideation and attempts. Methods: A total of 5051 (2872 girls and 2179 boys) adolescents who owned at least one cellular phone completed the research questionnaires. We collected data on participants' CPU and suicidal behavior (ideation and attempts) during the past month as well as information on family function and history of depression. Results: Five hundred thirty-two adolescents (10.54%) had problematic CPU. The rates of suicidal ideation were 23.50% and 11.76% in adolescents with problematic CPU and without problematic CPU, respectively. The rates of suicidal attempts in both groups were 13.70% and 5.45%, respectively. Family function, but not depression, had a moderating effect on the association between problematic CPU and suicidal ideation and attempt. Conclusion: This study highlights the association between problematic CPU and suicidal ideation as well as attempts and indicates that good family function may have a more significant role on reducing the risks of suicidal ideation and attempts in adolescents with problematic CPU than in those without problematic CPU. [ABSTRACT FROM AUTHOR]

Background/purpose: Surgical predictions for skeletal Class III patients have been reported to be the least accurate. Additionally, female patients tend to focus more on improving their facial esthetics. Therefore, this study was aimed at assessing the prediction accuracy of photocephalometry for skeletal Class III adult female patients treated with two-jaw surgery. Materials and methods: A photocephalometric investigation was undertaken to assess the prediction accuracy in a sample of 16 skeletal Class III female patients requiring bimaxillary orthognathic surgery. Tracings of cephalograms and one-to-one predicted photographs were carried out. Selected landmarks were digitized with a user-defined computer program. The prediction accuracy of the facial profile was estimated by evaluating discrepancies in landmark positions between post-surgical cephalograms and pre-planning photographs. Results: Predictions were generally accurate for all horizontal landmark variables and also for the upper lip in the vertical direction. Inaccuracies tended to occur in the vertical direction of the nasal base and lower lip. Mean differences in the predicted nasal base ranged from 1.00- 1.06 mm inferior to the actual position. In the lower lip, predictions tended to place the position as more superior, and mean discrepancies were 1.38 mm (for the lower stomion), 2.38 mm (labrale inferius), and 2.06 mm (inferior labial sulcus). Conclusions: In this study predictions were generally accurate in skeletal Class III adult female patients treated with two-jaw surgery. Compared to surgical outcomes, the predictions tended to locate the nasal base more inferior and the lower lip in a more superior position. Prediction inaccuracies and large individual variations found in this report were associated with difficulties in manual photographic manipulation and weak correlations in the vertical direction between the hard tissues and their corresponding soft tissues. [ABSTRACT FROM AUTHOR]

Background: Cognitive impairment in remitted late-life depression varies and might be associated with greater risk of dementia in some individuals. This study aimed to classify the subtypes of mild cognitive impairment (MCI) in late-life major depressive disorder in remission and to examine their clinical correlates and structural magnetic resonance imaging (MRI) features. Methods: Elderly patients with major depressive disorder in remission and elderly comparisons were examined by a comprehensive battery of cognitive tasks. Proposed diagnostic criteria were used for MCI classification, and the degree of brain atrophy and white matter hyperintensity on MRI were evaluated. Results: We found information-processing speed and memory were independent cognitive domains associated with late-life remitted major depressive disorder. Of the study cohort, 52.3% met the definition of MCI, including 28.5% with amnestic MCI (aMCI) and 23-8% with nonamnestic MCI (naMCI). A clinical correlate of aMCI was the late-onset of disorder (OR = 4.76; 95% CI = 1.57, 14.40) and of naMCI was a higher score on the Framingham stroke risk scale (OR = 1.39; 95% CI = 1.12, 1.72). The odds ratio of highest quartile of ventricular atrophy for aMCI compared to the comparisons was 3-65 (95% CI = 1.22, 10.96). Conclusions: The central cognitive impairments among the elderly with major depressive disorder in remission were memory and information-processing speed, and over half of the subjects met the MCI diagnostic criteria. Different risk factors existed for the subtypes of aMCI and naMCI. Later-age onset of first episode and ventricular atrophy were associated with aMCI, whereas vascular risk factor were associated with naMCI. We suggest there were different pathogeneses between aMCI and naMCI in late-life major depressive disorder. (Am J Geriatr Psychiatry 2011; 19:923-931) [ABSTRACT FROM AUTHOR]

Background: An elevated plasma homocysteine level has been reported to be associated with various neuropsychiatric diseases. However, little is known about the brain biochemical changes associated with the higher plasma homocysteine level. The main goal of this study was to examine the sex difference in brain biochemical concentrations using brain proton magnetic resonance spectroscopy (lH MRS), and to elucidate the biochemical changes associated with plasma homocysteine levels by sex in healthy elderly subjects. Methods: Seventy elderly subjects without any clinical psychiatric and neurological disease underwent 3-T brain ¹H MRS. MRS spectra were acquired from voxels placed on the left side of the basal ganglia, frontal lobe, and hippocampus. Brain biochemical concentrations were compared between the elderly male and female participants. Correlations between these biochemical concentrations and plasma homocysteine levels by sex were analyzed. Results: Female participants had significantly higher levels ofcholine in the left frontal lobe and hippocampus, and lower creatine and myo-inositol, in the left basal ganglia than did males. A higher homocysteine level was correlated with a lower N-acetylaspartate (NAA) concentration in the left hippocampus in elderly women (r = -0.44; p = 0.03) but not in elderly men. Conclusions: This study found that there was a sex difference in brain biochemical concentrations in the elderly participants. A higher plasma homocysteine level was associated with a lower NAA in the hippocampus of elderly women. The sex difference in association between brain biochemical concentrations and plasma homocysteine levels needs further investigation. We speculate that after menopause, women lose protection of estrogen from the neurotoxic effects of homocysteine in the hippocampus. Future studies are required to examine this speculation. [ABSTRACT FROM AUTHOR]

Background: The main aim of this study was to examine the symptomatology of major depression in Alzheimer disease (AD) and its relationship with plasma homocysteine level. Methods: Eighty-three patients with AD were enrolled for clinical assessments and examination of fasting plasma homocysteine. Diagnosis of major depression was made, and the severity of the depression was assessed. Results: The moderate dementia patients presented with more common behavioral disturbances related to major depression than mild dementia patients. Major depression in patients with moderate AD was associated with higher plasma homocysteine levels. Furthermore, a high plasma homocysteine level was positively associated with behavioral disturbance among study participants with major depression. Conclusion: More behavioral disturbance associated with major depression occurred as the dementia progressed. Patients with a higher level of plasma homocysteine presented with a higher behavioral disturbance symptomatology. This finding may account for the relationship between elevated homocysteine levels and depression only in patients with moderate AD. [ABSTRACT FROM AUTHOR]

Examines the redox properties of human endothelial nitric-oxide synthase oxygenase and reductase domains purified from yeast expression system. Importance of the characterization of the redox properties of endothelial nitric-oxide synthase (eNOS); Establishment of yeast overexpression of both the oxygenase and reductase domains of human eNOS; Expression and purification of eNOS subdomains; Spectroscopic characteristics of eNOS.

Biodegradable starch-based plastics are formed by combining corn starch with biodegradable poly(butylene adipate-co-terephthalate) (PBAT). Starch reduces the production cost and improves the biodegradability. However, starch reduces the ductility and toughness of biodegradable plastics, limiting their application. In this study the low molecular weight poly(ethylene ether carbonate) (LPEEC) is synthesized by the ring-opening polymerization of ethylene carbonate produced from the greenhouse gas CO 2. The extrusion combines starch-based plastic with LPEEC and provides plastics with increased tensile strength (by 3- to 4-fold) and elongation at break (by 4- to 5-fold), compared to that of plastics without LPEEC. The plastics with best mechanical properties are obtained using an LPEEC with the average molecular weights, molecular units of ethylene carbonate (E c) and ethylene oxide (E o) linkages of 3117 g/mol, 14, and 43, respectively. This is the first evidence of improving the properties of the starch-based polyester using LPEEC, which is suitable for biodegradable plastic. [Display omitted] • Adding LEPPC to starch-based plastic improves its strength and toughness. • Plastic blend using LEPPC of 3117 Da with 14 units of E c and 43 units of E o has maximum strength. • Hydrogen bonds among LEPPC, starch, and PBAT helps stabilize the compounded plastics. • The LPEEC can be produced from the greenhouse gas CO 2. [ABSTRACT FROM AUTHOR]

Prostacyclin synthase (PGIS) is a cytochrome P450 (P450) enzyme that catalyzes production of prostacyclin from prostaglandin H2. PGIS is unusual in that it catalyzes an isomerization rather than a monooxygenation, which is typical of P450 enzymes. To understand the structural basis for prostacyclin biosynthesis in greater detail, we have determined the crystal structures of ligand-free, inhibitor (minoxidil)-bound and substrate analog U51605-bound PGIS. These structures demonstrate a stereo-specific substrate binding and suggest features of the enzyme that facilitate isomerization. Unlike most microsomal P450s, where large substrate-induced conformational changes take place at the distal side of the heme, conformational changes in PGIS are observed at the proximal side and in the heme itself. The conserved and extensive heme propionate-protein interactions seen in all other P450s, which are largely absent in the ligand-free PGIS, are recovered upon U51605 binding accompanied by water exclusion from the active site. In contrast, when minoxidil binds, the propionate-protein interactions are not recovered and water molecules are largely retained. These findings suggest that PGIS represents a divergent evolution of the P450 family, in which a heme barrier has evolved to ensure strict binding specificity for prostaglandin H2, leading to a radical-mediated isomerization with high product fidelity. The U51605- bound structure also provides a view of the substrate entrance and product exit channels. [ABSTRACT FROM AUTHOR]

Endothelial nitric-oxide synthase (eNOS) plays important roles in vascular physiology and homeostasis. Whether eNOS catalyzes nitric oxide biosynthesis or the synthesis of reactive oxygen species such as superoxide, hydrogen peroxide, and peroxynitrite is dictated by the bioavailability of tetrahydrobiopterin (BH4) and L-arginine during eNOS catalysis. The effect of BH4 and Larginine on oxygen-induced radical intermediates has been investigated by single turnover rapid-freeze quench and EPR spectroscopy using the isolated eNOS oxygenase domain (eNOSox). Three distinct radical intermediates corresponding to >50% of the heme were observed during the reaction between ferrous eNOSox and oxygen. BH4-free eNOSox produced the superoxide radical very efficiently in the absence of L-arginine. L-Arginine decreased the formation rate of superoxide by an order of magnitude but not its final level or EPR line shape. For BH4-containing eNOSox, only a stoichiometric amount of BH4 radical was produced in the presence of L-arginine, but in its absence a new radical was obtained. This new radical could be either a peroxyl radical] of BH4 or an amino acid radical was in the vicinity of the heme. Formation of this new radical is very rapid, >150 s-1, and it was subsequently converted to a BH4 radical. The trapping of the superoxide radical by cytochrome c in the reaction of BH4(-) eNOSox exhibited a limiting rate of ∼15 s-1, the time for the superoxide radical to leave the heine pocket and reach the protein surface; this reveals a general problem of the regular spin-trapping method in determining radical formation kinetics. Cytochrome c failed to trap the new radical species. Together with other EPR characteristics, our data strongly support the conclusion that this new radical is not a superoxide radical or a mixture of superoxide and biopterin radicals. Our study points out distinct roles of BH4 and L-arginine in regulating eNOS radical intermediates. BH4 prevented superoxide formation by chemical conversions of the Fe(II)O2 intermediate, and L-arginine delayed superoxide formation by electronic interaction with the heme-bound oxygen. [ABSTRACT FROM AUTHOR]

Graphical abstract Inner C-cyanation and alkylation were observed in the reactions of 2- N -substituted N -confused tetraphenylporphyrin (2-NCH 2 YNCTPPH) with Co(SCN) 2. Abstract Some inner C-cyanation and C-alkylation complexes have been described. Reactions of 2- N -substituted N -confused tetraphenylporphyrin (2-NCH 2 YNCTPPH) with Co(SCN) 2 afford C-alkylation (14) and C-cyanation (15 – 17) complexes. The crystal structures for the inner C-alkylation product of thiocyanato(2-aza-2-[ p -methylbenzyl]-5,10,15,20-tetraphenyl-21-benzyl-21-carbaporphyrinato- N , N ′, N ″)cobalt(II)·0.5 octane solvate [Co(2-NCH 2 - p -CH 3 C 6 H 4 -21-CH 2 C 6 H 5 NCTPP)(NCS)·0.5C 8 H 18 ; 14 ·0.5C 8 H 18 ] and the inner C-cyanation products of thiocyanato(2-aza-2-ethoxycarbonylmethyl-5,10,15,20-tetraphenyl-21-cyano-21-carbaporphyrinato- N , N′ , N″)cobalt(II) [Co(2-NCH 2 COOCH 2 CH 3 -21-CN NCTPP) (NCS); 15 ], thiocyanato(2-aza-2-methyl-5,10,15,20-tetraphenyl-21-cyano-21-carbaporphyrinato- N , N′ , N″)cobalt(II)[Co(2-NCH 3 -21-CNNCTPP) (NCS); 16 ], and thiocyanato(2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-cyano-21-carbaporphyrinato- N , N′ , N″)cobalt(II) [Co(2-NCH 2 C 6 H 5 -21-CNNCTPP) (NCS); 17 ] have been reported. The geometry around Co2+ ion in these four complexes is a distorted tetrahedron with a C 2v symmetry. Two possible mechanisms were proposed to explain the formation of inner C-alkylation (14 ·0.5C 8 H 18) versus C-cyanation (15 – 17) products in these complexes with an axial *NCS− ligand. [ABSTRACT FROM AUTHOR]

Endometriosis is a common female reproductive disease characterized by invasion of endometrial cells into other organs, frequently causing pelvic pain and infertility. Alterations of the vitamin D system have been linked to endometriosis incidence and severity. To shed light on the potential mechanism for these associations, we examined the effects of 1,25(OH) 2 D 3 on gene expression in endometriosis cells. Stromal cell lines derived from endometriosis tissue were treated with 1,25(OH) 2 D 3 , and RNA-seq was used to identify genes differentially expressed between treated and untreated cells. Gene ontology and pathway analyses were carried out using Partek Flow and Ingenuity software suites, respectively. We identified 1627 genes that were differentially expressed (886 down-regulated and 741 up-regulated) by 1,25(OH) 2 D 3 . Only one gene, CYP24A1, was strongly up-regulated (369-fold). Many genes were strongly down-regulated. 1,25(OH) 2 D 3 treatment down-regulated several genetic pathways related to neuroangiogenesis, cellular motility, and invasion, including pathways for axonal guidance, Rho GDP signaling, and matrix metalloprotease inhibition. These findings support a role for vitamin D in the pathophysiology of endometriosis, and provide new targets for investigation into possible causes and treatments. [ABSTRACT FROM AUTHOR]