Publications by authors named "Christian Alexander"

Objective: Most studies examining the efficacy of ketamine for Major Depressive Disorder (MDD) have been conducted in outpatient or mixed inpatient/outpatient settings. Less is known about effectiveness and tolerability of ketamine for psychiatrically hospitalized patients. Efficacy and tolerability data from a naturalistic sample of acute inpatients may help inform institutions considering ketamine therapy for inpatient services.

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The myeloid C-type lectin receptor (CLR) MINCLE senses the mycobacterial cell wall component trehalose-6,6'-dimycolate (TDM). Recently, we found that IL-4 downregulates MINCLE expression in macrophages. IL-4 is a hallmark cytokine in helminth infections, which appear to increase the risk for mycobacterial infection and active tuberculosis.

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Leading experts on CRISPR/Cas-based genome editing-such as 2020 Nobel laureates Jennifer Doudna and Emmanuelle Charpentier-are not only renowned specialists in their fields, but also public advocates for upcoming regulatory frameworks on CRISPR/Cas. These frameworks will affect large portions of biomedical research on human genome editing. In advocating for particular ways of handling the risks and prospects of this technology, high-profile scientists not only serve as scientific experts, but also as moral advisers.

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TNF blockade is a successful treatment for human autoimmune disorders like rheumatoid arthritis and inflammatory bowel disease yet increases susceptibility to tuberculosis and other infections. The C-type lectin receptors (CLR) MINCLE, MCL, and DECTIN-2 are expressed on myeloid cells and sense mycobacterial cell wall glycolipids. In this study, we show that TNF is sufficient to upregulate MINCLE, MCL, and DECTIN-2 in macrophages.

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Electrostatic interactions between phosphate anions and Toll-like receptor 4 / Myeloid differentiation factor-2 (TLR4/MD-2) protein complexes of human, murine, equine and canine species were computed. Such knowledge can provide mechanistic information about recognising LPS-like ligands, since anionic phosphate groups belong to the structural features of LPS with their diphosphorylated diglucosamine backbone. Sequence composition analyses, electrostatic interaction potentials and docked energies as well as molecular dynamics studies evaluated the phosphate interactions within the triangular LPS binding site (wedge).

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Injections of a crude fetal sheep liver extract (FSLE) containing fetal hemoglobin, MPLA, and glutathione (GSSH) reversed cytokine changes in aged mice. To investigate the role of fetal hemoglobin we derived mice with homzygous deletions for either of the two major βchains, HgbβKO or HgbβKO. Hgbβ is the most prominent fetal Hgbβ chain, with Hgbβ more prominent in adult mice.

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Article Synopsis
  • Single-site blood pressure intervention programs have successfully improved BP levels, prompting an evaluation of the American Heart Association's Check. Change. Control (CCC) program across 18 cities with over 4000 patients.
  • The effectiveness of these interventions was assessed based on enrollment goals, participant engagement, and changes in BP from initial to final measurements.
  • High-performing sites often engaged senior institutions, provided education classes, distributed BP cuffs, and trained volunteers, showcasing that simplified, community-tailored programs can effectively enhance BP management, although outcomes varied significantly across different sites.
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Hemoglobin and its structures have been described since the 1990s to enhance a variety of biological activities of endotoxins (LPS) in a dose-dependent manner. To investigate the interaction processes in more detail, the system was extended by studying the interactions of newly designed peptides from the γ-chain of human hemoglobin with the adjuvant monophosphoryl lipid A (MPLA), a partial structure of lipid A lacking its 1-phosphate. It was found that some selected Hbg peptides, in particular two synthetic substructures designated Hbg32 and Hbg35, considerably increased the bioactivity of MPLA, which alone was only a weak activator of immune cells.

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Background: Clinical trial evidence suggests that statin therapy reduces adverse clinical events and provides even greater benefit at high-intensity doses in coronary artery disease (CAD) patients, yet few studies have examined this in clinical practice.

Methods: We linked detailed in-hospital data (2005-2009) on 15,729 Get With The Guidelines-CAD patients ≥65 years prescribed statins to Centers for Medicare and Medicaid Services claims. High-intensity statin therapy was defined as discharge prescription of atorvastatin ≥40 mg, rosuvastatin ≥20 mg, or simvastatin 80 mg.

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Sepsis, a life-threatening syndrome with increasing incidence worldwide, is triggered by an overwhelming inflammation induced by microbial toxins released into the bloodstream during infection. A well-known sepsis-inducing factor is the membrane constituent of Gram-negative bacteria, lipopolysaccharide (LPS), signalling via Toll-like receptor-4. Although sepsis is caused in more than 50% cases by Gram-positive and mycoplasma cells, the causative compounds are still poorly described.

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Endotoxins (LPS) are highly potent immune stimulatory molecules and are mainly known for triggering Gram-negative sepsis. However, besides their toxic effects, this stimulatory function may be advantageous, for example when used as an adjuvant during vaccination. Thus, there is always a narrow range between the useful wake-up of the immune system and its overwhelming reaction, which can lead to diseases like sepsis.

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Importance: Transcatheter aortic valve replacement (TAVR) was approved by the US Food and Drug Administration for the treatment of severe, symptomatic aortic stenosis and inoperable status (in 2011) and high-risk but operable status (starting in 2012). A national registry (the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy [STS/ACC TVT] Registry) was initiated to meet a condition for Medicare coverage and also facilitates outcome assessment and comparison with other trials and international registries.

Objective: To report the initial US commercial experience with TAVR.

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A literature review concerning the unexpected species differences of the vertebrate innate immune response to lipid IVA was published in CSBJ prior to the present computational study to address the unpaired activity-sequence correlation of prototypic E. coli -type lipid A and its precursor lipid IVA regarding human, murine, equine and canine species. To this end, their sequences and structures of hitherto known Toll-like receptor 4 (TLR4) and myeloid differentiation factor 2 (MD-2) complexes were aligned and their differential side chain patterns studied.

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There is literature evidence gathered throughout the last two decades reflecting unexpected species differences concerning the immune response to lipid IVa which provides the opportunity to gain more detailed insight by the molecular modeling approach described in this study. Lipid IVa is a tetra-acylated precursor of lipid A in the biosynthesis of lipopolysaccharide (LPS) in Gram-negative bacteria. Lipid A of the prototypic E.

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The interaction of selected endotoxin preparations (lipid A from Erwinia carotovora and LPS Re and Ra from Salmonella enterica sv. Minnesota strains R595 and R60, respectively) with selected bile acids was investigated biophysically. Endotoxin aggregates were analyzed for their gel-to-liquid crystalline phase behavior, the type of their aggregates, the conformation of particular functional groups, and their Zeta potential in the absence and presence of the bile acids by applying Fourier-transform infrared spectroscopy, differential scanning calorimetry, measurements of the electrophoretic mobility, and synchrotron radiation X-ray scattering.

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In 2006, the Thai National Health Security Office and the Ministry of Public Health, through the Nakhonratchasima Provincial Health Office in Thailand, asked the Thai-Australian Health Alliance to identify competencies and skills for a health management curriculum for health professionals working in primary healthcare in rural Thailand. The study was conducted in Nakhonratchasima province, Thailand, utilizing questionnaires, focus group discussions and an intensive 3-day workshop involving a purposive sample of 35 participants drawn from various sectors in the health industry. Findings identified the core curriculum competencies and skills required by rural doctors, nurses and public health officers.

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Proteome analyses provide diagnostic information which can be essential for therapeutic predictions. The application of such techniques for analyzing paraffin-embedded tissue samples is widely hampered by the use of formalin fixation requiring antigen retrieval procedures in molecular pathology. In prior studies, the HEPES-glutamic acid buffer-mediated organic solvent protection effect (HOPE) technique of tissue fixation has been shown to provide a broad array of biochemical investigations with excellent preservation of morphological structures, DNA, RNA, and proteins, thus supporting the multimethod analysis of archived specimens.

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Lipopolysaccharides (LPS, endotoxins) are main constituents of the outer membranes of Gram-negative bacteria, with the 'endotoxic principle' lipid A anchoring LPS into the membrane. When LPS is removed from the bacteria by the action of the immune system or simply by cell dividing, it may interact strongly with immunocompetent cells such as mononuclear cells. This interaction may lead, depending on the LPS concentration, to beneficial (at low) or pathophysiological (at high concentrations) reactions, the latter frequently causing the septic shock syndrome.

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Objective: To identify the needs of the region's general practitioners concerning diagnosing, treating and referring patients with mental health disorders and major barriers to the general practitioners' management of these patients.

Design: Cross-sectional survey.

Subjects: All general practitioners working in rural north-western New South Wales.

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Although hemoglobin (Hb) is mainly present in the cytoplasm of erythrocytes (red blood cells), lower concentrations of pure, cell-free Hb are released permanently into the circulation due to an inherent intravascular hemolytic disruption of erythrocytes. Previously it was shown that the interaction of Hb with bacterial endotoxins (lipopolysaccharides, LPS) results in a significant increase of the biological activity of LPS. There is clear evidence that the enhancement of the biological activity of LPS by Hb is connected with a disaggregation of LPS.

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Objective: To measure the health-related quality of life (HRQOL) of rural Australian Hepatitis C virus (HCV)-infected patients living in north-western New South Wales.

Design: A cross-sectional survey, including the Short Form 36 (SF36) questionnaire as well as topics concerning demographic data and items relating to the perceived mode and duration of HCV infection.

Subjects: A total of 80 patients with HCV infection were identified, using non-random, convenience sampling, during October 2004 to June 2005.

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Of all pattern recognition receptors (PRR) in innate immunity, Toll-like receptor 2 (TLR2) recognizes the structurally broadest range of different bacterial compounds known as pathogen-associated molecular patterns (PAMPs). TLR2 agonists identified so far are lipopolysaccharides (LPSs) from different bacterial strains, lipoproteins, (synthetic) lipopeptides, lipoarabinomannans, lipomannans, glycosylphosphatidylinositol, lipoteichoic acids (LTA), various proteins including lipoproteins and glycoproteins, zymosan, and peptidoglycan (PG). Because these molecules are structurally diverse, it seems unlikely that TLR2 has the capability to react with all agonists to the same degree.

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An understanding of details of the interaction mechanisms of bacterial endotoxins (lipopolysaccharide, LPS) with the oxygen transport protein hemoglobin is still lacking, despite its high biological relevance. Here, a biophysical investigation into the endotoxin:hemoglobin interaction is presented which comprises the use of various rough mutant LPS as well as free lipid A; in addition to the complete hemoglobin molecule from fetal sheep extract, also the partial structure alpha-chain and the heme-free sample are studied. The investigations comprise the determination of the gel-to-liquid crystalline phase behaviour of the acyl chains of LPS, the ultrastructure (type of aggregate structure and morphology) of the endotoxins, and the incorporation of the hemoglobins into artificial immune cell membranes and into LPS.

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Bacterial endotoxin (lipopolysaccharide, LPS) is the major component of the outer leaflet of the outer membrane in gram-negative bacteria. During severe infections, bacteria may reach the blood circuit of humans, and endotoxins may be released from the bacteria due to cell division or cell death. In particular enterobacterial forms of LPS represent extremely strong activator molecules of the human immune system causing a rapid induction of cytokine production in monocytes and macrophages.

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