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There is a paucity of data available on the context preceding anterior fusion failure or the need for a posterior fusion, the timing of the second operation, or any correlation between the different instrumentation and failure rates. A retrospective chart review was performed of 131 identified patients who underwent anterolateral corpectomy and fusion for a thoracolumbar burst fracture from 2000 to 2012 in a single institution. 96 patients had clinical and radiographic follow up of greater than two months. Mean kyphosis correction from preoperative (14.1°) to postoperative kyphosis (6.3°) was 7.7° and 37% had loss of kyphotic correction at follow-up. In a univariate analysis, use of a bone strut graft (OR 3.2, p = 0.01), point-loaded graft position (OR 4.9, p = 0.005), end plate damage/subsidence (OR 6.7, p < 0.0001), and graft to endplate width ratio of ≤ 45% on AP x-ray (OR 3.0, p = 0.02) were associated with loss of kyphotic correction. 41% demonstrated scoliosis of ≥ 5° at follow-up. Graft location towards the left of midline (OR 8.6, p < 0.0001), point-loaded graft position (OR 3.8, p = 0.01), and end plate damage/subsidence (OR 5.5, p = 0.0001) were also associated with scoliosis at the time of final follow-up. Five patients required posterior fusion and fifteen patients continued to have daily pain, only one of which was determined to be related to kyphosis. Use of a bone strut graft versus expandable cage, graft location, graft position, presence of early or late subsidence and width of the graft may be associated with loss of kyphotic correction and scoliosis., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Patients with advanced cancer often experience a reduced ability to eat, which may result in tensions between patients and family members. Often with advanced cancer diagnoses, patients' appetites decline markedly, while family members focus on nutritional intake with the hope that this will postpone death. This hope might cause tensions between the patient and family; the family may expect healthcare professionals to encourage the patient to eat more, whereas the patient needs to be supported in their reduced ability to eat. When these tensions arise, healthcare professionals can experience challenges in providing good palliative care. To address these challenges in the provision of palliative care, healthcare professionals may adopt a care ethics approach. Similar to palliative care's focus on patient and family members' relationships, a care ethics approach emphasizes interdependency and social relationships. Using Joan Tronto's care ethics approach, we conducted a normative analysis of what caring for patients with reduced ability to eat and their family members should look like. Tronto's approach includes five phases of care: caring about, taking care of, care giving, care-receiving, and caring with. Based on our analysis and empirical studies on patients with advanced cancer and family members, concerns with their lack of appetite, we assert that healthcare professionals must be mindful of the potential of tensions related to appetite and be adept in dealing with these tensions. We urge that education is needed for healthcare professionals regarding the psychosocial impact of reduced ability to eat on both patients and family members and interprofessional collaboration is of the essence., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Abstract: Short-Term Acute Residential Treatment (START) homes, located in the community and operating in noninstitutional atmospheres, seek to reduce rehospitalization. This report investigates whether these homes reduced rates and duration of subsequent inpatient stays in psychiatric hospitals. For 107 patients treated in START homes after psychiatric hospitalization, we compared the number and duration of psychiatric hospitalizations before and after their START stay. We found that, compared with the year before the START stay, in the year after the START stay, patients had fewer episodes of rehospitalization (1.60 [SD = 1.23] vs. 0.63 [SD = 1.05], t[106] = 7.097, p < 0.001) and a briefer accumulative duration of inpatient stays (41.60 days [SD = 49.4] vs. 26.60 days [SD = 53.25], t[106] = -2.32, p < 0.03). This suggests that START homes can reduce rehospitalization rates and should be considered a valid alternative to psychiatric hospitalization., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Objectives: To find causal genes for rheumatoid arthritis (RA) and its seropositive (RF and/or ACPA positive) and seronegative subsets., Methods: We performed a genome-wide association study (GWAS) of 31 313 RA cases (68% seropositive) and ~1 million controls from Northwestern Europe. We searched for causal genes outside the HLA-locus through effect on coding, mRNA expression in several tissues and/or levels of plasma proteins (SomaScan) and did network analysis (Qiagen)., Results: We found 25 sequence variants for RA overall, 33 for seropositive and 2 for seronegative RA, altogether 37 sequence variants at 34 non-HLA loci, of which 15 are novel. Genomic, transcriptomic and proteomic analysis of these yielded 25 causal genes in seropositive RA and additional two overall. Most encode proteins in the network of interferon-alpha/beta and IL-12/23 that signal through the JAK/STAT-pathway. Highlighting those with largest effect on seropositive RA, a rare missense variant in STAT4 (rs140675301-A) that is independent of reported non-coding STAT4 -variants, increases the risk of seropositive RA 2.27-fold (p=2.1×10 -9 ), more than the rs2476601-A missense variant in PTPN22 (OR=1.59, p=1.3×10 -160 ). STAT4 rs140675301-A replaces hydrophilic glutamic acid with hydrophobic valine (Glu128Val) in a conserved, surface-exposed loop. A stop-mutation (rs76428106-C) in FLT3 increases seropositive RA risk (OR=1.35, p=6.6×10 -11 ). Independent missense variants in TYK2 (rs34536443-C, rs12720356-C, rs35018800-A, latter two novel) associate with decreased risk of seropositive RA (ORs=0.63-0.87, p=10 -9 -10 -27 ) and decreased plasma levels of interferon-alpha/beta receptor 1 that signals through TYK2/JAK1/STAT4., Conclusion: Sequence variants pointing to causal genes in the JAK/STAT pathway have largest effect on seropositive RA, while associations with seronegative RA remain scarce., Competing Interests: Competing interests: Authors affiliated with deCODE Genetics/Amgen declare competing financial interests as employees. OAA is a consultant to HealthLytix. The following coauthors report the following but unrelated to the current report: Karolinska Institutet, with JA as principal investigator, has entered into agreements with the following entities, mainly but not exclusively for safety monitoring of rheumatology immunomodulators: Abbvie, BMS, Eli Lilly, Janssen, MSD, Pfizer, Roche, Samsung Bioepis and Sanofi, unrelated to the present study. SB has ownerships in Intomics A/S, Hoba Therapeutics Aps, Novo Nordisk A/S, Lundbeck A/S and managing board memberships in Proscion A/S and Intomics A/S. BG has received research grants from AbbVie, Bristol Myers-Squibb and Pfizer; OH has received research grants from AbbVie, Novartis and Pfizer, DVJ has received speaker and consultation fees from AbbVie, Janssen, Lilly, MSD, Novartis, Pfizer, Roche and UCB, AGL has received speaking and/or consulting fees from AbbVie, Janssen, Lilly, MSD, Novartis, Pfizer, Roche and UCB; and CT has received consulting fees from Roche, speaker fees from Abbvie, Bristol Myers-Squibb, Nordic Drugs, Pfizer and Roche, and an unrestricted grant from Bristol Myers-Squibb., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Previous studies on psychiatric patients infected with COVID-19 have reported a more severe course of disease and higher rates of mortality compared with the general population. This cohort study linked Israeli national databases including all individuals ever hospitalized for a psychiatric disorder (cases), and COVID-19 testing, infection, hospitalization, mortality, and vaccinations, between March 1 st 2020 and March 31 st 2021. Cases were 125,273 individuals aged 18 and above ever hospitalized in a psychiatric facility (ICD-10 F10-F69 or F90-F99), compared to the total population, n = 6,143,802. Compared with the total population, cases were less likely to be tested for COVID-19, 51.2% (95% CI: 50.8-51.7) vs 62.3% (95% CI 62.2-62.4) and had lower rates of confirmed COVID infection, 5.9% (95% CI: 5.8-6.1) vs 8.9% (95% CI: 8.9-8.9). Among those infected, risks for COVID-19 hospitalization, COVID-19 attributed mortality and all-cause mortality were higher for cases than the total population, adjusted odds ratios were 2.10; (95% CI: 1.96-2.25), 1.76; (95% CI: 1.54-2.01) and 2.02; (95% CI: 1.80-2.28), respectively. These risks were even higher for cases with non-affective psychotic disorders and bipolar disorder. Age adjusted rates of vaccination were lower in cases, 60.4% (95% CI: 59.9-60.8) vs 74.9% (95% CI: 74.8-75.0) in the total population, and particularly low for cases with non-affective psychotic disorders, 56.9% (95% CI: 56.3-57.6). This study highlights the need to increase testing for COVID-19 in individuals ever hospitalized for a psychiatric disorder, closely monitor those found positive, and to reach out to encourage vaccination., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Uncertainty in the representation of biomass burning (BB) aerosol composition and optical properties in climate models contributes to a range in modeled aerosol effects on incoming solar radiation. Depending on the model, the top-of-the-atmosphere BB aerosol effect can range from cooling to warming. By relating aerosol absorption relative to extinction and carbonaceous aerosol composition from 12 observational datasets to nine state-of-the-art Earth system models/chemical transport models, we identify varying degrees of overestimation in BB aerosol absorptivity by these models. Modifications to BB aerosol refractive index, size, and mixing state improve the Community Atmosphere Model version 5 (CAM5) agreement with observations, leading to a global change in BB direct radiative effect of -0.07 W m -2 , and regional changes of -2 W m -2 (Africa) and -0.5 W m -2 (South America/Temperate). Our findings suggest that current modeled BB contributes less to warming than previously thought, largely due to treatments of aerosol mixing state.

Multilevel societies (MLSs), stable nuclear social units within a larger collective encompassing multiple nested social levels, occur in several mammalian lineages. Their architectural complexity and size impose specific demands on their members requiring adaptive solutions in multiple domains. The functional significance of MLSs lies in their members being equipped to reap the benefits of multiple group sizes. Here, we propose a unifying terminology and operational definition of MLS. To identify new avenues for integrative research, we synthesise current literature on the selective pressures underlying the evolution of MLSs and their implications for cognition, intersexual conflict, and sexual selection. Mapping the drivers and consequences of MLS provides a reference point for the social evolution of many taxa, including our own species., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Previous studies reported an association between advanced paternal age at birth and increased risk for schizophrenia and bipolar disorder. While some hypothesize that this association is caused by de-novo mutations in paternal spermatozoa, others cite factors associated with psycho-social characteristics of fathers who have children at a late age. This study aims to test these hypotheses., Methods: A historical-prospective, population-based cohort study, performed by linking the Israeli Draft Board Registry and the Israeli National Psychiatric Hospitalization Registry (N = 916 439; 4488 with schizophrenia, 883 with bipolar disorder). Odds ratios (OR) and two-sided 95% confidence intervals (CI) were calculated by logistic regression models, using paternal age as predictor and risk for later hospitalizations for schizophrenia or bipolar disorder as outcome measure. Models were first fitted unadjusted, then adjusted for paternal age at birth of the first child., Results: In the unadjusted model, offspring of fathers aged 45 and above at birth had increased risk of schizophrenia (OR = 1.71, 95% CI 1.49-1.99) and bipolar disorder (OR = 1.63, 95% CI 1.16-2.24). However, taking into account paternal age at birth of first child, advanced paternal age was no longer associated with increased risk of schizophrenia (OR = 0.60, 95% CI 0.48-0.79) or bipolar disorder (OR = 1.03, 95% CI 0.56-1.90)., Conclusions: Controlling for paternal age at birth of the first offspring, advanced paternal age does not predict increased risk for schizophrenia or bipolar disorder. These data indicate that the association between advanced paternal age and having an offspring with schizophrenia and bipolar disorder is likely due to psychos-social factors, or common genetic variation associated with delayed initial fatherhood.

Typically, the left anterior descending artery (LAD) and left circumflex artery (LCX) arise from the left main coronary artery. However, uncommon coronary anomalies may be found in clinical practice. This case presents with a rare finding where the LAD originates from the right coronary artery (RCA) separately from the LCX and takes an interarterial pathway to reach its perfusion territory. A 49-year-old Hispanic female with hypertension and diabetes mellitus presented to the emergency department with a 7-day history of chest pain. She denied nausea, diaphoresis, syncope, or other symptoms. A grade 3 out of 6 systolic murmur was noted on physical examination. Computed tomography of the pulmonary arteries (CTPA) revealed that the patient had no left main coronary artery. The patient's LAD arose from the proximal RCA and took an inter-arterial course. Subsequent coronary catheterization showed no stenosis of the coronary arterial system. The patient's chest pain subsided during the course of her admission and she was deemed stable for discharge with close cardiology follow up. In general, coronary artery anomalies are an uncommon finding in clinical practice. However, it is important to realize the different pathways of coronary artery anomalies because those with the inter-arterial subtype, such as our patient, may result in sudden cardiac death. All cases of clinically suspected inter-arterial coronary artery anomalies are recommended to undergo imaging studies to help visualize anatomic features as a guide for further management. This case represents the first reported diagnosis of this type of anomalous coronary artery on CTPA., (Copyright © 2019 Elsevier Inc. All rights reserved.)

A total of 16 global chemistry transport models and general circulation models have participated in this study; 14 models have been evaluated with regard to their ability to reproduce the near-surface observed number concentration of aerosol particles and cloud condensation nuclei (CCN), as well as derived cloud droplet number concentration (CDNC). Model results for the period 2011-2015 are compared with aerosol measurements (aerosol particle number, CCN and aerosol particle composition in the submicron fraction) from nine surface stations located in Europe and Japan. The evaluation focuses on the ability of models to simulate the average across time state in diverse environments and on the seasonal and short-term variability in the aerosol properties. There is no single model that systematically performs best across all environments represented by the observations. Models tend to underestimate the observed aerosol particle and CCN number concentrations, with average normalized mean bias (NMB) of all models and for all stations, where data are available, of -24% and -35% for particles with dry diameters > 50 and > 120nm, as well as -36% and -34% for CCN at supersaturations of 0.2% and 1.0%, respectively. However, they seem to behave differently for particles activating at very low supersaturations (< 0.1 %) than at higher ones. A total of 15 models have been used to produce ensemble annual median distributions of relevant parameters. The model diversity (defined as the ratio of standard deviation to mean) is up to about 3 for simulated N 3 (number concentration of particles with dry diameters larger than 3 nm) and up to about 1 for simulated CCN in the extra-polar regions. A global mean reduction of a factor of about 2 is found in the model diversity for CCN at a supersaturation of 0.2% (CCN 0.2 ) compared to that for N 3 , maximizing over regions where new particle formation is important. An additional model has been used to investigate potential causes of model diversity in CCN and bias compared to the observations by performing a perturbed parameter ensemble (PPE) accounting for uncertainties in 26 aerosol-related model input parameters. This PPE suggests that biogenic secondary organic aerosol formation and the hygroscopic properties of the organic material are likely to be the major sources of CCN uncertainty in summer, with dry deposition and cloud processing being dominant in winter. Models capture the relative amplitude of the seasonal variability of the aerosol particle number concentration for all studied particle sizes with available observations (dry diameters larger than 50, 80 and 120 nm). The short-term persistence time (on the order of a few days) of CCN concentrations, which is a measure of aerosol dynamic behavior in the models, is underestimated on average by the models by 40% during winter and 20% in summer. In contrast to the large spread in simulated aerosol particle and CCN number concentrations, the CDNC derived from simulated CCN spectra is less diverse and in better agreement with CDNC estimates consistently derived from the observations (average NMB -13% and -22% for updraft velocities 0.3 and 0.6 ms -1 , respectively). In addition, simulated CDNC is in slightly better agreement with observationally derived values at lower than at higher updraft velocities (index of agreement 0.64 vs. 0.65). The reduced spread of CDNC compared to that of CCN is attributed to the sublinear response of CDNC to aerosol particle number variations and the negative correlation between the sensitivities of CDNC to aerosol particle number concentration ( ∂N d / ∂N a ) and to updraft velocity ( ∂N d / ∂w ). Overall, we find that while CCN is controlled by both aerosol particle number and composition, CDNC is sensitive to CCN at low and moderate CCN concentrations and to the updraft velocity when CCN levels are high. Discrepancies are found in sensitivities ∂N d / ∂N a and ∂N d /∂ w ; models may be predisposed to be too "aerosol sensitive" or "aerosol insensitive" in aerosol-cloud-climate interaction studies, even if they may capture average droplet numbers well. This is a subtle but profound finding that only the sensitivities can clearly reveal and may explain inter-model biases on the aerosol indirect effect., Competing Interests: Competing interests. The authors declare that they have no conflict of interest.

Evolutionary research benefits form the integration of laboratory and field components to determine factors and processes that affect the evolutionary trajectories of species. Our shared interest in understanding hybridization with genetic admixture as a process that may impact social, behavioral, and ecological features of primates, brought us together in a collaborative project aimed at addressing how vocal variation in two species of howler monkeys in Mexico affects and is affected by hybridization. To achieve this goal, we joined our academic expertise in studying primate genetics, ecology, and behavior under different natural and experimental conditions. We took advantage of decades of experience studying and handing wild howler monkeys for translocation projects to safely sample and study wild populations for this project. Here, we describe the history of our collaboration highlighting how our different perspectives, academic realities, and individual strengths built the foundation for our successful collaboration. We also share our perspectives on how this collaboration opened up new academic venues, broadened our individual perspectives on the integration of different research approaches to address a complex topic, and allowed us to recognize the strength of international collaboration., (© 2019 Wiley Periodicals, Inc.)

αδ-Bungarotoxins, a novel group of long-chain α-neurotoxins, manifest different affinity to two agonist/competitive antagonist binding sites of muscle-type nicotinic acetylcholine receptors (nAChRs), being more active at the interface of α-δ subunits. Three isoforms (αδ-BgTx-1-3) were identified in Malayan Krait ( Bungarus candidus ) from Thailand by genomic DNA analysis; two of them (αδ-BgTx-1 and 2) were isolated from its venom. The toxins comprise 73 amino acid residues and 5 disulfide bridges, being homologous to α-bungarotoxin (α-BgTx), a classical blocker of muscle-type and neuronal α7, α8, and α9α10 nAChRs. The toxicity of αδ-BgTx-1 (LD 50  = 0.17-0.28 µg/g mouse, i.p. injection) is essentially as high as that of α-BgTx. In the chick biventer cervicis nerve-muscle preparation, αδ-BgTx-1 completely abolished acetylcholine response, but in contrast with the block by α-BgTx, acetylcholine response was fully reversible by washing. αδ-BgTxs, similar to α-BgTx, bind with high affinity to α7 and muscle-type nAChRs. However, the major difference of αδ-BgTxs from α-BgTx and other naturally occurring α-neurotoxins is that αδ-BgTxs discriminate the two binding sites in the Torpedo californica and mouse muscle nAChRs showing up to two orders of magnitude higher affinity for the α-δ site as compared with α-ε or α-γ binding site interfaces. Molecular modeling and analysis of the literature provided possible explanations for these differences in binding mode; one of the probable reasons being the lower content of positively charged residues in αδ-BgTxs. Thus, αδ-BgTxs are new tools for studies on nAChRs., (© 2019 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.)

OBJECTIVE Increased understanding of the consequences of traumatic brain injury has heightened concerns about youth participation in contact sports. This study investigated the prevalence of high school and collegiate contact sports play and concussion history among surgical department chairs. METHODS A cross-sectional survey was administered to 107 orthopedic and 74 neurosurgery chairs. Responses were compared to published historical population norms for contact sports (high school 27.74%, collegiate 1.44%), football (high school 10.91%, collegiate 0.76%), and concussion prevalence (12%). One-proportion Z-tests, chi-square tests, and binary logistic regression were used to analyze differences. RESULTS High school contact sports participation was 2.35-fold higher (65.3%, p < 0.001) for orthopedic chairs and 1.73-fold higher (47.9%, p = 0.0018) for neurosurgery chairs than for their high school peers. Collegiate contact sports play was 31.0-fold higher (44.7%, p < 0.001) for orthopedic chairs and 15.1-fold higher (21.7%, p < 0.001) for neurosurgery chairs than for their college peers. Orthopedic chairs had a 4.30-fold higher rate of high school football participation (46.9%, p < 0.001) while neurosurgery chairs reported a 3.05-fold higher rate (33.3%, p < 0.001) than their high school peers. Orthopedic chairs reported a 28.1-fold higher rate of collegiate football participation (21.3%, p < 0.001) and neurosurgery chairs reported an 8.58-fold higher rate (6.5%, p < 0.001) compared to their college peers. The rate at which orthopedic (42.6%, p < 0.001) and neurosurgical (42.4%, p < 0.001) chairs reported having at least 1 concussion in their lifetime was significantly higher than the reported prevalence in the general population. After correction for worst possible ascertainment bias, all results except high school contact sports participation remained significant. CONCLUSIONS The high prevalence of youth contact sports play and concussion among surgical specialty chairs affirms that individuals in careers requiring high motor and cognitive function frequently played contact sports. The association highlights the need to further examine the relationships between contact sports and potential long-term benefits as well as risks of sport-related injury.

Reporting of sports-related concussions (SRCs) has risen dramatically over the last decade, increasing awareness of the need for treatment and prevention of SRCs. To date most prevention studies have focused on equipment and rule changes to sports in order to reduce the risk of injury. However, increased neck strength has been shown to be a predictor of concussion rate. In the TRAIN study, student-athletes will follow a simple neck strengthening program over the course of three years in order to better understand the relationship between neck strength and SRCs. Neck strength of all subjects will be measured at baseline and biannually over the course of the study using a novel protocol. Concussion severity and duration in any subject who incurs an SRC will be evaluated using the Sports Concussion Assessment Tool 5th edition, a questionnaire based tool utilizing several tests that are commonly affected by concussion, and an automated eye tracking algorithm. Neck strength, and improvement of neck strength, will be compared between concussed and non-concussed athletes to determine if neck strength can indeed reduce risk of concussion. Neck strength will also be analyzed taking into account concussion severity and duration to find if a strengthening program can provide a protective factor to athletes. The study population will consist of student-athletes, ages 12-23, from local high schools and colleges. These athletes are involved in a range of both contact and non-contact sports.

There has been no major advancement in a quarter of a century for the treatment of acute severe traumatic brain injury (TBI). This review summarizes 40 years of clinical and pre-clinical research on the treatment of acute TBI with hyperbaric oxygen therapy (HBO 2 ) in the context of an impending National Institute of Neurologic Disorders and Stroke-funded, multi-center, randomized, adaptive Phase II clinical trial -the Hyperbaric Oxygen Brain Injury Treatment (HOBIT) trial. Thirty studies (eight clinical and 22 pre-clinical) that administered HBO 2 within 30 days of a TBI were identified from PubMed searches. The pre-clinical studies consistently reported positive treatment effects across a variety of outcome measures with almost no safety concerns, thus providing strong proof-of-concept evidence for treating severe TBI in the acute setting. Of the eight clinical studies reviewed, four were based on the senior author's (GR) investigation of HBO 2 as a treatment for acute severe TBI. These studies provided evidence that HBO 2 significantly improves physiologic measures without causing cerebral or pulmonary toxicity and can potentially improve clinical outcome. These results were consistent across the other four reviewed clinical studies, thus providing preliminary clinical data supporting the HOBIT trial. This comprehensive review demonstrates that HBO 2 has the potential to be the first significant treatment in the acute phase of severe TBI.

Background: Psychiatrists may face challenging core medical ethics questions since the media encourages their assistance and participation at various levels. This paper examines attitudes of psychiatrists regarding their involvement with the media and their view of their professional association in such incidents., Methods: A survey was completed by a convenience sample of 81 Israeli psychiatrists. The specially designed questionnaire was compiled by the research team focusing on potential involvement of the psychiatrist regarding reality shows; discussing criminality and responsibility in the media; media involvement of the national psychiatric association and appearing in the media in matters of public education and mental health literacy., Results: Psychiatrists are largely reluctant to engage with the mass media. At the same time, they support a strong media presence by their professional psychiatric association., Conclusion: Professional psychiatry associations should consider deliberating the issue of media involvement further and contemplate further development of ethical recommendations on the issue.

Pre-B-cell leukemia homeobox (PBX) transcription factors are known to regulate organogenesis, but their molecular targets and function in midbrain dopaminergic neurons (mDAn) as well as their role in neurodegenerative diseases are unknown. Here, we show that PBX1 controls a novel transcriptional network required for mDAn specification and survival, which is sufficient to generate mDAn from human stem cells. Mechanistically, PBX1 plays a dual role in transcription by directly repressing or activating genes, such as Onecut2 to inhibit lateral fates during embryogenesis, Pitx3 to promote mDAn development, and Nfe2l1 to protect from oxidative stress. Notably, PBX1 and NFE2L1 levels are severely reduced in dopaminergic neurons of the substantia nigra of Parkinson's disease (PD) patients and decreased NFE2L1 levels increases damage by oxidative stress in human midbrain cells. Thus, our results reveal novel roles for PBX1 and its transcriptional network in mDAn development and PD, opening the door for new therapeutic interventions., (© 2016 The Authors.)

Leukotriene C4 synthase (LTC4S) catalyzes the formation of the proinflammatory lipid mediator leukotriene C4 (LTC4). LTC4 is the parent molecule of the cysteinyl leukotrienes, which are recognized for their pathogenic role in asthma and allergic diseases. Cellular LTC4S activity is suppressed by PKC-mediated phosphorylation, and recently a downstream p70S6k was shown to play an important role in this process. Here, we identified Ser(36) as the major p70S6k phosphorylation site, along with a low frequency site at Thr(40), using an in vitro phosphorylation assay combined with mass spectrometry. The functional consequences of p70S6k phosphorylation were tested with the phosphomimetic mutant S36E, which displayed only about 20% (20 μmol/min/mg) of the activity of WT enzyme (95 μmol/min/mg), whereas the enzyme activity of T40E was not significantly affected. The enzyme activity of S36E increased linearly with increasing LTA4 concentrations during the steady-state kinetics analysis, indicating poor lipid substrate binding. The Ser(36) is located in a loop region close to the entrance of the proposed substrate binding pocket. Comparative molecular dynamics indicated that Ser(36) upon phosphorylation will pull the first luminal loop of LTC4S toward the neighboring subunit of the functional homotrimer, thereby forming hydrogen bonds with Arg(104) in the adjacent subunit. Because Arg(104) is a key catalytic residue responsible for stabilization of the glutathione thiolate anion, this phosphorylation-induced interaction leads to a reduction of the catalytic activity. In addition, the positional shift of the loop and its interaction with the neighboring subunit affect active site access. Thus, our mutational and kinetic data, together with molecular simulations, suggest that phosphorylation of Ser(36) inhibits the catalytic function of LTC4S by interference with the catalytic machinery., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

Background: In Israel a general code of ethics exists for physicians, drafted by the Israel Medical Association. The question arises whether psychiatrists require a separate set of ethical guidelines., Objectives: To examine the positions of Israeli psychiatrists with regard to ethics in general and professional ethics in particular, and to explore opinions regarding a code of ethics or ethical guidelines for psychiatry.  Methods: A specially designed questionnaire was compiled and completed by psychiatrists recruited for the study., Methods: A specially designed questionnaire was compiled and completed by psychiatrists recruited for the study., Results: Most participants reported low levels of perceived knowledge regarding ethics, professional ethics, and the general code of ethics. Older and more experienced professionals reported a higher level of knowledge. Most psychiatrists agreed or strongly agreed with the need for a distinct code of ethics/ethical guidelines for psychiatrists. This support was significantly higher among both psychiatrists under 50 years and residents., Conclusions: Our findings suggest that the existing code of ethics and position papers may not be sufficient, indicating a potential need to develop and implement a process to create the ethical code itself. In addition, the findings highlight the importance of ethics education, suggesting that the need for a code of ethics is more urgent in the early stages of professional training, as younger professionals may be more exposed to advanced media technology. While some may fear that a distinct code of ethics will distance psychiatry from modern medicine, others assert that the profession combines aspects from the humanities and social sciences that require a unique sort of management and thus this profession requires a distinct code of ethics.

Emergency and disaster situations such as war or terrorism can leave a devastating impact on the mental well-being of victimized populations. In Israel, the civilian aspects of trauma-related mental distress were first extensively tackled during the 1980s, and mainly within the terror-stricken Jerusalem and the localities along the northern border. Since then, a systematic process of trial and error has led to the evolution of emergency mental health services in the country. Over the course of about forty years, it has grown to be an exemplary one. It is a system deeply rooted in the ground, resulting from both a change of discourse and a naturalistic process of lesson learning, that is, drawing conclusions from actual fieldwork. This process and its implications on the mental well-being of Israelis are thoroughly discussed in this research.

An 84-residue bactericidal peptide, PSK, was purified from a Chrysomya megacephala fly larvae preparation. Its amino acid sequence is similar to that of a previously reported larval peptide of the Drosophila genus (SK84) noticed for its anticancer and antimicrobial properties. The PSK sequence is also homologous to mitochondrial ATPase inhibitors from insects to humans (35-65% sequence identity), indicating an intracellular protein target and possible mechanism for PSK. It contains a cluster of six glycine residues, and has several two- and three-residue repeats. It is active against both Gram-positive and Gram-negative bacteria via a mechanism apparently involving cell membrane disintegration and inhibition of ATP hydrolysis. In addition, PSK induces an inward cationic current in pancreatic β cells. Together, the findings identify a bioactive peptide of the ATPase inhibitor family with specific effects on both prokaryotic and mammalian cells., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Testamentary capacity refers to an individual's capability to write his or her own will. Psychiatrists are required occasionally to give expert opinions regarding the testamentary capacity of individuals with a medical history or suspected diagnosis of a mental illness. This may stem from the patient/lawyer/ family initiative to explore the current capacity to testate in anticipation of a possible challenge, or may be sought when testamentary capacity of a deceased has been challenged. In this article we examine the medico-legal construct of testamentary capacity of the schizophrenic patient, and discuss the various clinical situations specific to schizophrenic patients, highlighting their impact on the medical opinion regarding testamentary capacity through examining the rulings of Israel's Supreme Court in a specific case where the testamentary capacity of a mentally ill individual who was challenged postmortem, and provide a workable framework for the physician to evaluate the capacity of a schizophrenic patient to write a will..

Institutional ethics committees were established and functioned in Israel prior to the application of the Patients Rights Act of 1996. These committees were voluntary and comprised of multidisciplinary teams in order to obtain numerous viewpoints stemming from various different fields. This intent was based on an understanding that the issue of ethics and the process of making ethical decisions inherently address moral and social considerations which are beyond the realm of medical practice. In contrast to the voluntary institutional ethics committees, the Patients Rights Act of 1996 instituted statutory ethics committees. These committees were mandated to investigate defined areas and, in contrast to the former committees that were considered to be valuable as advisory and enlightening entities, their decisions are binding. However, it appears that the utilization of these ethics committees within the domain of mental health facilities is limited in scope and their use varies greatly between institutions. The employment of these committees in mental health institutions focuses mainly around issues that relate to information management and mentally ill patients' refusal of medical treatment. Several explanations exist for this phenomenon. Suggestions as to how the situation may be remedied are addressed as well as the complementary role that these ethics committees may play in modern day clinical practice.

Different lines of alcohol dehydrogenases (ADHs) have separate superfamily origins, already recognized but now extended and re-evaluated by re-screening of the latest databank update. The short-chain form (SDR) is still the superfamily with most abundant occurrence, most multiple divergence, most prokaryotic emphasis, and most non-complicated architecture. This pattern is compatible with an early appearance at the time of the emergence of prokaryotic cellular life. The medium-chain form (MDR) is also old but second in terms of all the parameters above, and therefore compatible with a second emergence. However, this step appears seemingly earlier than previously considered, and may indicate sub-stages of early emergences at the increased resolution available from the now greater number of data entries. The Zn-MDR origin constitutes a third stage, possibly compatible with the transition to oxidative conditions on earth. Within all these three lines, repeated enzymogeneses gave the present divergence. MDR-ADH origin(s), at a fourth stage, may also be further resolved in multiple or extended modes, but the classical liver MDR-ADH of the liver type can still be traced to a gene duplication ~550 MYA (million years ago), at the early vertebrate radiation, compatible with the post-eon-shift, "Cambrian explosion". Classes and isozymes correspond to subsequent and recent duplicatory events, respectively. They illustrate a peculiar pattern with functional and emerging evolutionary distinctions between parent and emerging lines, suggesting a parallelism between duplicatory and mutational events, now also visible at separate sub-stages. Combined, all forms show distinctive patterns at different levels and illustrate correlations with global events. They further show that simple molecular observations on patterns, multiplicities and occurrence give much information, suggesting common divergence rules not much disturbed by horizontal gene transfers after the initial origins., (Copyright © 2012. Published by Elsevier Ireland Ltd.)

Background: Allergy to dog (Canis familiaris) is a worldwide common cause of asthma and allergic rhinitis. However, dander extract in routine diagnostics is not an optimal predictor of IgE-mediated dog allergy. Our objective was to evaluate saliva as an allergen source for improved diagnostics of allergy to dog., Methods: IgE-binding proteins in dog saliva and dander extract were analysed by immunoblot and mass spectrometry (LC-MS/MS) using pooled or individual sera from dog-allergic patients (n = 13). Sera from 59 patients IgE positive to dander and 55 patients IgE negative to dander but with symptoms to dog were analysed for IgE against saliva and dander by ELISA. Basophil stimulation with dog saliva and dander extract was measured by flow cytometry among three dog-allergic patients. Additionally, IgE-binding protein profiles of saliva from different breeds were investigated by immunoblot., Results: Greater number and diversity of IgE-binding proteins was found in saliva compared to dander extract and varied among dog breeds. In saliva, Can f 1, 2, 3 and 6 were identified but also four new saliva allergen candidates. The majority of the 59 dog dander-positive sera (n = 44) were IgE positive to dog saliva. Among patients IgE negative to dander, but with symptoms to dog, 20% were IgE positive to saliva. The biological activity of saliva was confirmed by basophil degranulation., Conclusions: Dog saliva is an allergen source for improved diagnostics of dog allergy. The IgE-binding protein profile of saliva from different dogs varies., (© 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.)

In patients with schizophrenia, consent postmortem for organ donation for transplantation and research is usually obtained from relatives. By means of a questionnaire, the authors investigate whether patients with schizophrenia would agree to family members making such decisions for them as well as compare decisions regarding postmortem organ transplantation and brain donation between patients and significant family members. Study results indicate while most patients would not agree to transplantation or brain donation for research, a proportion would agree. Among patients who declined organ donation for transplantation or brain research, almost half of family members would have agreed to brain donation for research and over 40% to organ transplantation. Male relatives are more likely to agree to organ donation from their deceased relatives for both transplantation and research. The authors argue that it is important to respect autonomy and interests of research subjects even if mentally ill and even if no longer living. Consent may be assisted by appropriate educational interventions prior to patient death.

HIV-1 enters cells via interaction of the viral glycoprotein gp120, the host cell surface receptor CD4 and the co-receptors CCR5 or CXCR4. For entry, gp120 undergoes conformational changes that depend on the reduction of one or more disulfides. Previous studies indicate that protein disulfide isomerase (PDI), thioredoxin-1 (Trx1), and glutaredoxin-1 (Grx1) catalyze gp120 reduction, but their specific disulfide targets are not known. Here, it was demonstrated that PDI and Trx1 have similar gp120 disulfide targets as determined by labeling after reduction, but with some pattern differences, including overall stronger labeling with Trx1 than with PDI. Furthermore, uneven labeling of the residues of a disulfide may reflect altered accessibility by conformational changes upon the reduction process. Since both PDI and Trx1 may be involved in viral entry, compounds that target the host redox system or the viral gp120 were tested in vitro to investigate whether redox regulation is a target for anti-HIV therapy. Carbohydrate binding agents (CBAs), previously shown to bind gp120 and inhibit HIV entry, were now demonstrated to inhibit gp120 disulfide reduction. Auranofin, an inhibitor of thioredoxin reductase 1 (TrxR1), also showed inhibitory activity towards HIV infection, although close to its cytotoxic concentration. Our results demonstrate that both the host redox system and the viral surface glycoproteins are of interest for the development of new generations of anti-HIV therapeutics., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

BRICHOS domains are encoded in > 30 human genes, which are associated with cancer, neurodegeneration, and interstitial lung disease (ILD). The BRICHOS domain from lung surfactant protein C proprotein (proSP-C) is required for membrane insertion of SP-C and has anti-amyloid activity in vitro. Here, we report the 2.1 Å crystal structure of the human proSP-C BRICHOS domain, which, together with molecular dynamics simulations and hydrogen-deuterium exchange mass spectrometry, reveals how BRICHOS domains may mediate chaperone activity. Observation of amyloid deposits composed of mature SP-C in lung tissue samples from ILD patients with mutations in the BRICHOS domain or in its peptide-binding linker region supports the in vivo relevance of the proposed mechanism. The results indicate that ILD mutations interfering with proSP-C BRICHOS activity cause amyloid disease secondary to intramolecular chaperone malfunction.

Unlabelled: One of the pathways leading to androgen independence in prostate cancer involves upregulation of insulinlike growth factor type 1 receptor (IGF-1R). Radionuclide imaging of IGF-1R in tumors might be used for selection of patients who would most likely benefit from IGF-1R-targeted therapy. The goal of this study was to evaluate the feasibility of in vivo radionuclide imaging of IGF-1R expression in prostate cancer xenografts using a small nonimmunoglobulin-derived binding protein called an Affibody molecule., Methods: The IGF-1R-binding Z(IGF1R:4551) Affibody molecule was site-specifically conjugated with a maleimido derivative of DOTA and labeled with (111)In. The binding of radiolabeled Z(IGF1R:4551) to IGF-1R-expressing cells was evaluated in vitro and in vivo., Results: DOTA-Z(IGF1R:4551) can be stably labeled with (111)In with preserved specific binding to IGF-1R-expressing cells in vitro. In mice, (111)In-DOTA-Z(IGF1R:4551) accumulated in IGF-1R-expressing organs (pancreas, stomach, lung, and salivary gland). Receptor saturation experiments demonstrated that targeting of DU-145 prostate cancer xenografts in NMRI nu/nu mice was IGF-1R-specific. The tumor uptake was 1.1 ± 0.3 percentage injected dose per gram, and the tumor-to-blood ratio was 3.2 ± 0.2 at 8 h after injection., Conclusion: This study demonstrates the feasibility of in vivo targeting of IGF-1R-expressing prostate cancer xenografts using an Affibody molecule. Further development of radiolabeled Affibody molecules might provide a useful clinical tool for stratification of patients with prostate cancer for IGF-1R-targeting therapy.

Background and Importance: Chordomas are relatively rare tumors that arise from the neuraxis. Most often, chordomas are single lesions that metastasize late. There have been very few cases of chordomas arising from multiple foci along the neuraxis. Here, we present a case of a multicentric chordoma., Clinical Presentation: The patient presented with pain in her right neck and soreness in her right shoulder that she had experienced for about 2.5 years that she attributed to a muscle strain. She experienced worsening of her symptoms, which prompted her to seek medical care. The patient underwent an occiput-to-C6 posterolateral fusion with autograft and an occiput-to-C6 posterior segmental instrumentation, along with decompression of the spinal cord. One month after the initial surgery, the patient underwent a second surgery. The C2 and C3 vertebral bodies were completely resected, and a C1-C4 anterior fusion was then carried out. A C5 vertebrectomy and C4-C6 fusion were also performed at this time. The patient then received proton beam radiation to the entire affected area., Conclusion: Recent studies have suggested that chordomas arise from benign notochordal tumors. We suggest that our patient suffered from multicentric chordomas with possible benign notochordal tumors. Although benign notochordal tumors do not require surgical resection, the possibility of transformation to a malignant lesion requires close follow-up.

The study of protein structure and function has evolved to become a leading discipline in the biophysical sciences. Although it is not yet possible to determine 3D protein structures from MS data alone, multiple MS-based techniques can be combined to obtain structural and functional data that are complementary to classical protein structure information obtained from NMR or X-ray crystallography. Monitoring gas-phase interactions of noncovalent complexes yields information on binding constants, complex stability, and the nature of interactions. Ion mobility MS and chemical crosslinking strategies can be applied to probe the architecture of macromolecular assemblies and protein-ligand complexes. MS analysis of hydrogen-deuterium exchange can be used to determine the localization of secondary structure elements, binding sites and conformational dynamics of proteins in solution. This minireview focuses first on new strategies that combine these techniques to gain insights into protein structure and function. Using one such strategy, we then demonstrate how a novel hydrogen-deuterium exchange microfluidics tool can be used online with an ESI mass spectrometer to monitor regional accessibility in a peptide, as exemplified with amyloid-β peptide 1-40., (© 2011 The Authors Journal compilation © 2011 FEBS.)

A membrane cell for hydrogen and deuterium exchange on-line with mass spectrometry has been developed to monitor protein-protein interactions and protein conformations. It consists of two channels separated by a semipermeable membrane, where one channel carries the protein sample and the other deuterium oxide. The membrane allows transfer of deuterium oxide into the sample flow. The labeling time is controlled via the flow rate in the sample channel. This cell was validated against three models commonly used in hydrogen-deuterium exchange mass spectrometry: monitoring of folded and unfolded states in a protein, mapping the protein secondary structure at the peptide level, and detection of protein and antibody interactions. The system avoids the conventionally used sample dilution and handling, allowing for potential automation.

There is little data on suicide among elderly depressed patients seeking psychiatric help. Recent studies have demonstrated that physical illness may increase this risk. We aimed to assess, retrospectively, the association between suicide and physical illness among depressed elderly psychiatric patients. All medical records of patients admitted during a 10-year period to an acute psychiatric ward, after having attempted suicide, were reviewed. Inclusion criteria were: age>65 years, diagnosis of a depressive disorder and intact cognition. The comparison group consisted of previous or subsequent admissions, closest (by date), of elderly patients, matching the inclusion criteria, but without previous record of attempting suicide, into the same ward. The cumulative illness rating scale (CIRS) score was calculated for each patient. 78 admissions of elderly depressed patients, who had attempted suicide before hospitalization, were examined. The comparison group (n=87) consisted of the subsequent admission of a similar but not suicidal pre-admission patient. The CIRS total score was significantly higher among suicidal patients (10.2 vs. 8.0; p=0.0008). Suicidal patients scored higher in the vascular and the respiratory sections of CIRS. Our results support reported findings of higher rates of illness among suicidal elderly patients. The CIRS may be considered an additional tool in assessing risk for suicide in elderly psychiatric subjects., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

The number of incarcerated sex offenders in the Israeli prison system has steadily increased during the past decade. While treatment of sex offenders is complex, treatment of those in prison seems to be more challenging. This publication presents major considerations and dilemmas, clinical as well as ethics-related, derived from the experience of the psychiatric division in the Israeli prison service in treating sex offenders in this special setting. The psychiatrist treating the incarcerated offender must always maintain a sensitive balance between the needs and wishes of his patient and the potential threat to society stemming from recidivism.

Spider dragline silk, one of the strongest polymers in nature, is composed of proteins termed major ampullate spidroin (MaSp) 1 and MaSp2. The N-terminal (NT) domain of MaSp1 produced by the nursery web spider Euprosthenops australis acts as a pH-sensitive relay, mediating spidroin assembly at around pH 6.3. Using amide hydrogen/deuterium exchange combined with mass spectrometry (MS), we detected pH-dependent changes in deuterium incorporation into the core of the NT domain, indicating global structural stabilization at low pH. The stabilizing effects were diminished or abolished at high ionic strength, or when the surface-exposed residues Asp40 and Glu84 had been exchanged with the corresponding amides. Nondenaturing electrospray ionization MS revealed the presence of dimers in the gas phase at pH values below--but not above--6.4, indicating a tight electrostatic association that is dependent on Asp40 and Glu84 at low pH. Results from analytical ultracentrifugation support these findings. Together, the data suggest a mechanism whereby lowering the pH to <6.4 results in structural changes and alteration of charge-mediated interactions between subunits, thereby locking the spidroin NT dimer into a tight entity important for aggregation and silk formation., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

The courts have recently become increasingly involved in the administration of compulsory psychiatric services in Israel. Data reveal a gradual increase in the rate of court-ordered hospitalizations according to Section 15 of the Law for the Treatment of the Mentally Ill. This paper examines the implications of this trend, particularly the issues of security and safety in psychiatric hospitalization. We present highlights from extensive British experience, focusing on the implications on forensic psychiatry in Israel. We review the development of the hierarchy of security in the British psychiatric services, beginning in the early 1970s with the establishment of the Butler Committee that determined a hierarchy of three levels of security for the treatment of patients, culminating with the establishment of principles for the operation of medium security units in Britain (Read Committee, 1991). These developments were the basis for the forensic psychiatric services in Britain. We discuss the relevance of the British experience to the situation in Israel while examining the current status of mental health facilities in Israel. In our opinion, a safe and suitable environment is a necessary condition for a treatment setting. The establishment of medium security units or forensic psychiatry departments within a mental health facility will enable the concentration and classification of court-ordered admissions and will enable systemic flexibility and capacity for better treatment, commensurate with patient needs.

Two large gene and protein superfamilies, SDR and MDR (short- and medium-chain dehydrogenases/reductases), were originally defined from analysis of alcohol and polyol dehydrogenases. The superfamilies contain minimally 82 and 25 genes, respectively, in humans, minimally 324 and 86 enzyme families when known lines in other organisms are also included, and over 47,000 and 15,000 variants in existing sequence data bank entries. SDR enzymes have one-domain subunits without metal and MDR two-domain subunits without or with zinc, and these three lines appear to have emerged in that order from the universal cellular ancestor. This is compatible with their molecular architectures, present multiplicity, and overall distribution in the kingdoms of life, with SDR also of viral occurrence. An MDR-zinc, when present, is often, but not always, catalytic. It appears also to have a structural role in inter-domain interactions, coenzyme binding and substrate pocket formation, as supported by domain variability ratios and ligand positions. Differences among structural and catalytic zinc ions may be relative and involve several states. Combined, the comparisons trace evolutionary properties of huge superfamilies, with partially redundant enzymes in cellular redox functions., (2010 Elsevier Inc. All rights reserved.)

Wnts are secreted, lipidated proteins that regulate multiple aspects of brain development, including dopaminergic neuron development. In this study, we perform the first purification and signaling analysis of Wnt2 and define the function of Wnt2 in ventral midbrain precursor cultures, as well as in Wnt2-null mice in vivo. We found that purified Wnt2 induces the phosphorylation of both Lrp5/6 and Dvl-2/3, and activates beta-catenin in SN4741 dopaminergic cells. Moreover, purified Wnt2 increases progenitor proliferation, and the number of dopaminergic neurons in ventral midbrain precursor cultures. In agreement with these findings, analysis of the ventral midbrain of developing Wnt2-null mice revealed a decrease in progenitor proliferation and neurogenesis that lead to a decrease in the number of postmitotic precursors and dopaminergic neurons. Collectively, our observations identify Wnt2 as a novel regulator of dopaminergic progenitors and dopaminergic neuron development.

Prions are infectious agents resulting from the conversion of a normal cellular protein, PrP(C), to a misfolded species, PrP(Sc). Iatrogenic transmission of prions is known from surgical procedures involving stainless steel materials. Here, it was shown that stainless steel containing nickel and molybdenum binds PrP(Sc) more efficiently and transmits infection to cells in culture to a higher degree than if these elements are not present. Furthermore, both nickel and molybdenum alone adsorbed PrP(Sc), and nickel powder could be used to extract PrP(Sc) from dilute solutions, thus providing a simple approach to concentration of PrP(Sc). The fact that nickel and molybdenum in steel alloys increased the binding affinity, and bound infectivity, of PrP(Sc) is an important issue to consider in the manufacture of surgical instruments and abattoir tools.

The C-terminal domain of lung surfactant protein C (CTC) precursor (proSP-C) is involved in folding of the transmembrane segment of proSP-C. CTC includes a Brichos domain with homologs in cancer- and dementia-associated proteins. Mutations in the Brichos domain cause misfolding of proSP-C and hence amyloid fibril formation in interstitial lung disease. Electrospray ionization mass spectrometry (ESI-MS) with collision-induced dissociation (CID) experiments was applied to study non-covalent interactions between human recombinant CTC or its Brichos domain, and SP-C analogs, homotripeptides and peptides designed to model amyloid fibril formation. The results show that the Brichos domain contains the peptide-binding function of CTC. In titration experiments, apparent dissociation constants (KD) were in the micromolar range where triple-valine showed the lowest KD and triple-tyrosine the highest. Non-hydrophobic peptides failed to form complexes with Brichos. CID revealed that complexes with aromatic peptide ligands are more stable in the gas phase than complexes with non-aromatic ligands. The Brichos domain was also shown to bind fibril-forming peptides containing aromatic/hydrophobic residues., (Copyright 2009 John Wiley & Sons, Ltd.)

The binding of zinc (Zn) ions to proteins is important for many cellular events. The theoretical and computational description of this binding (as well as that of other transition metals) is a challenging task. In this paper the binding of the Zn ion to four cysteine residues in the structural site of horse liver alcohol dehydrogenase (HLADH) is studied using a synthetic peptide mimic of this site. The study includes experimental measurements of binding constants, classical free energy calculations from molecular dynamics (MD) simulations and quantum mechanical (QM) electron structure calculations. The classical MD results account for interactions at the molecular level and reproduce the absolute binding energy and the hydration free energy of the Zn ion with an accuracy of about 10%. This is insufficient to obtain correct free energy differences. QM correction terms were calculated from density functional theory (DFT) on small clusters of atoms to include electronic polarisation of the closest waters and covalent contributions to the Zn-S coordination bond. This results in reasonably good agreement with the experimentally measured binding constants and Zn ion hydration free energies in agreement with published experimental values. The study also includes the replacement of one cysteine residue to an alanine. Simulations as well as experiments showed only a small effect of this upon the binding free energy. A detailed analysis indicate that the sulfur is replaced by three water molecules, thereby changing the coordination number of Zn from four (as in the original peptide) to six (as in water).

Two hydroxy-functional hyperbranched aliphatic polyesters based on 2,2-dimethylolpropionic acid (bis-MPA) and a partially aromatic conventional polyester have been studied as thermoset resins for solvent-borne thermally cured polyester cross-linked with melamine coatings for precoated sheet metal, i.e., coil coatings. The hyperbranched polyesters differ with respect to the ratio of the end groups, being either hydroxyls or alkyl esters. The rheological properties of formulations with different polyester resin composition and reactive diluent, i.e., rape seed methyl ester, content have been evaluated with viscosity measurements. Films cured either under industrial cure conditions to obtain a peak metal temperature of 232-241 degrees C or at a lower temperature, i.e., 130 degrees C, on untreated or organic primer-coated hot-dipped-galvanized steel substrates have been prepared. The film properties have been evaluated with differential scanning calorimetry and conventional film characterization techniques, i.e., adhesion, impact, Erichsen cupping, pencil hardness, microhardness, and scratch and chemical resistance tests. Formulations possessing high drying ability with maintained suitable film application viscosity were obtained using a hyperbranched polyester resin and a reactive diluent. It is proposed that a solvent-free polyester/melamine formulation with sufficient film properties to withstand the rough forming procedures associated with coil coatings can be obtained by further modification of the resin and greater amounts of reactive diluent.

Zinc plays an important role in the structure and function of many enzymes, including alcohol dehydrogenases (ADHs) of the MDR type (mediumchain dehydrogenases/reductases). Active site zinc participates in catalytic events, and structural site zinc maintains structural stability. MDR-types of ADHs have both of these zinc sites but with some variation in ligands and spacing. The catalytic zinc sites involve three residues with different spacings from two separate protein segments, while the structural zinc sites involve four residues and cover a local segment of the protein chain (Cys97-Cys111 in horse liver class I ADH). This review summarizes properties of both ADH zinc sites, and relates them to zinc sites of proteins in general. In addition, it highlights a separate study of zinc binding peptide variants of the horse liver ADH structural zinc site. The results show that zinc coordination of the free peptide differs markedly from that of the enzyme (one His / three Cys versus four Cys), suggesting that the protein zinc site is in an energetically strained conformation relative to that of the peptide. This finding is a characteristic of an entatic state, implying a functional nature for this zinc site.

Zinc binding to the peptide replica and analogs to residues 93-115 of horse liver alcohol dehydrogenase (ADH) was examined by competition of the peptides and the chromophoric chelator 4-(2- pyridylazo)resorcinol for zinc and X-ray absorption fine structure analysis of the zinc ligands. In the enzyme, zinc is coordinated by four Cys residues. In the peptide replica, zinc is bound to three Cys and one His residue. A four-Cys zinc coordination is observed only when His is removed, leading to increased zinc stability. ADH crystal structures reveal that the epsilon-amino group of the conserved residue Lys323 is within H-bond distance of the backbone amide oxygens of residues 103, 105 and 108, likely stabilizing the zinc coordination in the enzyme. The peptide data thus indicate structural strain and increased energy in the zinc-binding site in the protein, characteristic of an entatic state, implying a functional nature for this zinc site.