66 research outputs found
Studies of the Precipitation Pattern of Paclitaxel in Intravenous Infusions and Rat Plasma Using Laser Nephelometry
Cremophor EL (CrEL) is commonly used to solubilize paclitaxel (Ptx); a widely established anticancer agent used against many types of cancer. Using laser-based microplate nephelometry, in this work we assessed the precipitation kinetics of Ptx in CrEL-containing formulations upon dilutions with different infusion media or upon introduction into rat plasma. The precipitation profile of Ptx was assessed for a Taxol-like formulation and compared with a preparation with reduced CrEL content. These two formulations were diluted at various ratios in compatible infusion media and with or without rat plasma. The percentages of Ptx precipitated in dilution media and protein-binding in plasma were quantified using HPLC. The findings of turbidity measurements were in good agreement with HPLC. Despite the presence of albumin, it was possible to assess turbidity within infusion solutions and predict Ptx precipitation. Upon addition to plasma, no precipitation in Taxol-like formulation occurred after 2 h. In contrast, precipitation occurred immediately in CrEL-reduced formulation. It is possible that the high percentage of protein-bound Ptx in plasma (98.5–99.2%) has inhibited drug precipitation. Turbidity measurements using laser nephelometry can provide a rapid screening tool when developing intravenous formulations for poorly soluble drugs, such as Ptx and assess its stability upon dilution in animal plasma
Interaction of Temperature and Light in the Development of Freezing Tolerance in Plants
Abstract Freezing tolerance is the result of a wide range
of physical and biochemical processes, such as the induction
of antifreeze proteins, changes in membrane composition,
the accumulation of osmoprotectants, and changes
in the redox status, which allow plants to function at low
temperatures. Even in frost-tolerant species, a certain period
of growth at low but nonfreezing temperatures, known
as frost or cold hardening, is required for the development
of a high level of frost hardiness. It has long been known
that frost hardening at low temperature under low light
intensity is much less effective than under normal light
conditions; it has also been shown that elevated light
intensity at normal temperatures may partly replace the
cold-hardening period. Earlier results indicated that cold
acclimation reflects a response to a chloroplastic redox
signal while the effects of excitation pressure extend
beyond photosynthetic acclimation, influencing plant
morphology and the expression of certain nuclear genes
involved in cold acclimation. Recent results have shown
that not only are parameters closely linked to the photosynthetic
electron transport processes affected by light
during hardening at low temperature, but light may also
have an influence on the expression level of several other
cold-related genes; several cold-acclimation processes can
function efficiently only in the presence of light. The
present review provides an overview of mechanisms that
may explain how light improves the freezing tolerance of
plants during the cold-hardening period
Efect of maleated anhydride on mechanical properties of rice husk filler reinforced PLA Matrix Polymer Composite
Polylactic acid (PLA) formulated from corn starch has a bright potential to replace the non-renewable petroleum-based
plastics. The combination of PLA and natural fbre has gained interest due to its unique performance, as reported in many
researches and industries. Meanwhile, rice husk produced as the by-product of rice milling can be utilised, unless it is
turned completely into waste. Therefore, in the present study, the rice husk powder (RHP) was used as a fller in the PLA,
so to determine the infuence of the fller loading on the mechanical properties of the PLA composite. A coupling agent was
selected for treatment from two options, i.e., maleic anhydride polypropylene (MAPP) and maleic anhydride polyethylene
(MAPE), by applying the agents with various loading contents, such as 2, 4 and 6 wt%. The composite was fabricated by
using the hot compression machine. Both the treated and untreated RHP–PLA composites were characterised via the tensile,
fexural and impact strength tests. The increase in the RHP loading content led to the decrease in the tensile and fexural
strengths. The applications of the coupling agents (MAPE and MAPP) did not improve the tensile and impact strengths, but
the fexural strength was enhanced
Emotional behavior in aquatic organisms? Lessons from crayfish and zebrafish
Experimental animal models are a valuable tool to study the neurobiology of emotional behavior and mechanisms underlying human affective disorders. Mounting evidence suggests that various aquatic organisms, including both vertebrate (e.g., zebrafish) and invertebrate (e.g., crayfish) species, may be relevant to study animal emotional response and its deficits. Ideally, model organisms of disease should possess considerable genetic and physiological homology to mammals, display robust behavioral and physiological responses to stress, and should be sensitive to a wide range of drugs known to modulate stress and affective behaviors. Here, we summarize recent findings in the field of zebrafish- and crayfish-based tests of stress, anxiety, aggressiveness and social preference, and discuss further perspectives of using these novel model organisms in translational biological psychiatry. Outlining the remaining questions in this field, we also emphasize the need in further development and a wider use of crayfish and zebrafish models to study the pathogenesis of affective disorders. © 2019 Wiley Periodicals, Inc.MCS is currently supported by National Funds through FCT ‐ Foundation for Science and Technology. AVK is supported by the Russian Science Foundation grant 19‐15‐00053. KAD is supported by the Fellowship of the President of Russia and SPSU Rector Productivity Fellowship for PhD Students. CM is supported by CNPq/Brazil under Edital Universal 2016 (400726/2016‐5). PMA and FB are supported by the strategic plan of MARE ‐ Marine and Environmental Sciences Centre (UID/MAR/04292/2019)
24-Epibrassinolide Pre-Treatment Modifies Cold-Induced Photosynthetic Acclimation Mechanisms and Phytohormone Response of Perennial Ryegrass in Cultivar-Dependent Manner
Phylogenomic analysis of the Chlamydomonas genome unmasks proteins potentially involved in photosynthetic function and regulation
Chlamydomonas reinhardtii, a unicellular green alga, has been exploited as a reference organism for identifying proteins and activities associated with the photosynthetic apparatus and the functioning of chloroplasts. Recently, the full genome sequence of Chlamydomonas was generated and a set of gene models, representing all genes on the genome, was developed. Using these gene models, and gene models developed for the genomes of other organisms, a phylogenomic, comparative analysis was performed to identify proteins encoded on the Chlamydomonas genome which were likely involved in chloroplast functions (or specifically associated with the green algal lineage); this set of proteins has been designated the GreenCut. Further analyses of those GreenCut proteins with uncharacterized functions and the generation of mutant strains aberrant for these proteins are beginning to unmask new layers of functionality/regulation that are integrated into the workings of the photosynthetic apparatus
Violence by proxy in Othello syndrome
Delusional disorder that is based upon jealousy is known as the Othello syndrome. The delusion concerns the fidelity of the partner. An affected person usually perceives any kind of incident as proof of infidelity, which is totally in the imagination of the patient. The patients might take many extraordinary actions against their partners. These may include restricting the autonomy of the partner and getting violent. In this report, we present the case of a male patient who believed his wife was cheating on him. In order to prevent her from cheating he forced his wife to have surgery. Although she did not have any related health problems, in order to hinder her sexual life, he persuaded a doctor to remove his wife's uterus. She underwent total abdominal hysterectomy. This case was found to be interesting due to the proxy violence associated with the delusion. In this case, it is conspicuous that the violence was not inflicted directly, but it was took place with the help of a doctor. Physicians should be careful with patients with a delusional disorder of the jealousy type, especially when delivering health care to either the patient or their partner. © 2004 Librapharm Limited
The Role of Acyl Lipids in Reconstitution of Lipid-Depleted Light-Harvesting Complex II from Cold-Hardened and Nonhardened Rye
Effect of moisture absorption on the mechanical performance of natural fiber reinforced woven hybrid bio-composites
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