The site of synthesis of the iron-sulfur subunits of the flavoprotein and iron-protein fractions of human NADH dehydrogenase

The site of synthesis of the iron-sulfur subunits of the flavoprotein and iron-protein fractions of the human respiratory chain NADH dehydrogenase has been investigated to test the possibility that any of them is synthesized in mitochondria. For this purpose, antibodies specific for individual subunits of the bovine enzyme, which cross- reacted with the homologous human subunits in immunoblot assays, were tested against HeLa cell mitochondrial proteins labeled in vivo with [35S]methionine in the absence or presence of inhibitors of mitochondrial or cytoplasmic protein synthesis. The results clearly indicated that all the iron-sulfur subunits of the flavoprotein and iron-protein fractions of human complex I are synthesized in the cytosol and are, therefore, encoded in nuclear genes

Two-step separation of nostotrebin 6 from cultivated soil cyanobacterium (Nostoc sp.) by high performance countercurrent chromatography

High performance countercurrent chromatography (HPCCC) was successfully applied for the separation of nostotrebin 6 from cultivated soil cyanobacteria in a two-step operation. A two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (4:5:4:5, v/v/v/v) was employed for the HPCCC separation. In the first-step operation, its neutral upper phase was used as stationary phase and its basic lower phase (1% NH3 in lower phase) was employed as mobile phase at a flow rate of 1 mL/min. In the second operation step, its neutral upper phase was used as stationary phase, whereas both its neutral lower phase and basic lower phase were employed as mobile phase with a linear gradient elution at a flow rate of 0.8 mL/min. The revolution speed and temperature of the separation column were 1,000 rpm and 30 °C, respectively. Using HPCCC followed by clean-up on Sephadex LH-20 gel, 4 mg of nostotrebin 6 with a purity of 99% as determined by HPLC/DAD-ESI-HRMS was obtained from 100 mg of crude extract. The chemical identity of the isolated compound was confirmed by comparing its spectroscopic data (UV, ESI-HRMS, ESI-HRMS2) with those of an authentic standard and data available in the literature.This work was supported by the project ALGAIN (reg. nr. CZ.1.07/2.3.00/30.0059) and the Center for Algal Biotechnology Třeboň-ALGATECH (CZ. 1.05/21.00/03.0110)

An evaluation of the fixed concentration procedure for assessment of acute inhalation toxicity

Acute inhalation studies are conducted in animals as part of chemical hazard identification and for classification and labelling. Current methods employ death as an endpoint (OECD TG403 and TG436) while the recently approved fixed concentration procedure (FCP) (OECD TG433) uses fewer animals and replaces lethality as an endpoint with evident toxicity. Evident toxicity is the presence of clinical signs that predict that exposure to the next highest concentration will cause severe toxicity or death in most animals. Approval of TG433 was the result of an international initiative, led by the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), which collected data from six laboratories on clinical signs recorded for inhalation studies on 172 substances. This paper summarises previously published data and describes the additional analyses of the dataset that were essential for approval of the TG

Metal Ions in Neuroscience

Metal ions are believed to participate in many neurodegenerative conditions. In excitotoxic cell death there is convincing evidence for the participation of Ca2+ and Zn2+ ions although the exact molecular mechanisms by which these metals exert their effects are unclear. Only in one instance has the metal binding site of metalloenzymes been exploited for therapeutic purposes and this is the use of Li+ in the treatment of bipolar affective disorder. Again the exact molecular target is not clear but is likely to involve a Mg2+-dependent enzyme of an intracellular signalling pathway. In Parkinson's disease, the selective loss of dopaminergic neurones in the substantia nigra may be caused by radical-mediated damage and there is good evidence to suggest that Fe2+ or 3+ is important in promoting formation of radical species. The evidence that free radicals are important in mediating other neurodegenerative conditions is less strong but still substantial enough to suggest that removal of reactive oxygen species or preventing their formation may be a valid approach to therapy

Collaborative Supply Chain Decision Support And Multi-Attribute Supply Chain Scenarios

Todays Global economy is putting a premium on the ability of companies and their professional employees to rapidly evaluate a broad range of decisions in collaboration with both existing and prospective supply chain partners. This includes the development, evaluation and refinement of product designs, the evaluation of alternatives sourcing options, the evaluation of requests for bids, etc. A key difficulty in supporting the collaborative development, evaluation and refinement of alternative courses of action across different organizations lies in the complexity of the solutions involved (e.g. complex production schedules spanning multiple organizations, complex product designs or configurations involving large numbers of parts and components that are procured from a number of suppliers, etc.). Given a growing and ongoing need to revitalize the accounting curriculum and explore eclectic methods to teach accounting information systems, real challenges and opportunities exist to import this material into the accounting systems classroom.The Business Process Integration Lab at Saint Josephs University has developed a prototype environment for collaborative development, evaluation and refinement of supply chain management scenarios (e.g. requests for bids, product designs, sourcing options). The environment relies on the use of Enterprise Resource Planning software, using SAP R/3 to streamline and integrate the supply chain. Through the use of application scenarios, students are able to develop a total understanding of the power of the ERP technology tool as a decision maker and problem-solver, while enhancing their knowledge of the system in modules such as Production Planning and Customer Order Management. It is possible to support powerful workflow management functionality in the context of both interactive and highly automated decision making processes. This functionality has been operational for some three years and is coordinated by senior level graduate and undergraduate students who develop and test the scenarios and assist other students as they navigate through the R/3 system

Improving Translational Relevance in Preclinical Psychopharmacology (iTRIPP)

Animal models are important in preclinical psychopharmacology to study mechanisms and potential treatments for psychiatric disorders. A working group of 14 volunteers, comprising an international team of researchers from academia and industry, convened in 2021 to discuss how to improve the translational relevance and interpretation of findings from animal models that are used in preclinical psychopharmacology. The following paper distils the outcomes of the working group’s discussions into 10 key considerations for the planning and reporting of behavioural studies in animal models relevant to psychiatric disorders. These form the iTRIPP guidelines (Improving Translational Relevance In Preclinical Psychopharmacology). These guidelines reflect the key considerations that the group thinks will likely have substantial impact in terms of improving the translational relevance of behavioural studies in animal models that are used to study psychiatric disorders and their treatment. They are relevant to the research community when drafting and reviewing manuscripts, presentations and grant applications. The iTRIPP guidelines are intended to complement general recommendations for planning and reporting animal studies that have been published elsewhere, by enabling researchers to fully consider the most appropriate animal model for the research purpose and to interpret their findings appropriately. This in turn will increase the clinical benefit of such research and is therefore important not only for the scientific community but also for patients and the lay public

Cryo-EM structural analysis of FADD:Caspase-8 complexes defines the catalytic dimer architecture for co-ordinated control of cell fate.

Regulated cell death is essential in development and cellular homeostasis. Multi-protein platforms, including the Death-Inducing Signaling Complex (DISC), co-ordinate cell fate via a core FADD:Caspase-8 complex and its regulatory partners, such as the cell death inhibitor c-FLIP. Here, using electron microscopy, we visualize full-length procaspase-8 in complex with FADD. Our structural analysis now reveals how the FADD-nucleated tandem death effector domain (tDED) helical filament is required to orientate the procaspase-8 catalytic domains, enabling their activation via anti-parallel dimerization. Strikingly, recruitment of c-FLIPS into this complex inhibits Caspase-8 activity by altering tDED triple helix architecture, resulting in steric hindrance of the canonical tDED Type I binding site. This prevents both Caspase-8 catalytic domain assembly and tDED helical filament elongation. Our findings reveal how the plasticity, composition and architecture of the core FADD:Caspase-8 complex critically defines life/death decisions not only via the DISC, but across multiple key signaling platforms including TNF complex II, the ripoptosome, and RIPK1/RIPK3 necrosome

Cryo-EM structural analysis of FADD:Caspase-8 complexes defines the catalytic dimer architecture for co-ordinated control of cell fate.

Regulated cell death is essential in development and cellular homeostasis. Multi-protein platforms, including the Death-Inducing Signaling Complex (DISC), co-ordinate cell fate via a core FADD:Caspase-8 complex and its regulatory partners, such as the cell death inhibitor c-FLIP. Here, using electron microscopy, we visualize full-length procaspase-8 in complex with FADD. Our structural analysis now reveals how the FADD-nucleated tandem death effector domain (tDED) helical filament is required to orientate the procaspase-8 catalytic domains, enabling their activation via anti-parallel dimerization. Strikingly, recruitment of c-FLIPS into this complex inhibits Caspase-8 activity by altering tDED triple helix architecture, resulting in steric hindrance of the canonical tDED Type I binding site. This prevents both Caspase-8 catalytic domain assembly and tDED helical filament elongation. Our findings reveal how the plasticity, composition and architecture of the core FADD:Caspase-8 complex critically defines life/death decisions not only via the DISC, but across multiple key signaling platforms including TNF complex II, the ripoptosome, and RIPK1/RIPK3 necrosome