1,891 research outputs found

    Data-Driven Modeling of the Cellular Pharmacokinetics of Degradable Chitosan-Based Nanoparticles

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    Nanoparticle drug delivery vehicles introduce multiple pharmacokinetic processes, with the delivery, accumulation, and stability of the therapeutic molecule influenced by nanoscale processes. Therefore, considering the complexity of the multiple interactions, the use of data-driven models has critical importance in understanding the interplay between controlling processes. We demonstrate data simulation techniques to reproduce the time-dependent dose of trimethyl chitosan nanoparticles in an ND7/23 neuronal cell line, used as an in vitro model of native peripheral sensory neurons. Derived analytical expressions of the mean dose per cell accurately capture the pharmacokinetics by including a declining delivery rate and an intracellular particle degradation process. Comparison with experiment indicates a supply time constant, τ = 2 h. and a degradation rate constant, b = 0.71 h−1. Modeling the dose heterogeneity uses simulated data distributions, with time dependence incorporated by transforming data-bin values. The simulations mimic the dynamic nature of cell-to-cell dose variation and explain the observed trend of increasing numbers of high-dose cells at early time points, followed by a shift in distribution peak to lower dose between 4 to 8 h and a static dose profile beyond 8 h

    Nurses\u27 Alumnae Association Bulletin - Volume 18 Number 1

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    Alumnae Notes Central Dressing Room Committee Reports Digest of Alumnae Association Meetings Graduation Awards - 1952 Greetings from Miss Childs Greetings from the President Marriages Modern Trends in Orthopaedic Surgery Necrology New Arrivals Physical Advances at Jefferson Hospital - 1953 Staff Activities - 1952-1953 Student Activities The Artificial Heart Lung Machin

    Distribution, composition and functions of gelatinous tissues in deep-sea fishes

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    Many deep-sea fishes have a gelatinous layer, or subdermal extracellular matrix, below the skin or around the spine. We document the distribution of gelatinous tissues across fish families (approx. 200 species in ten orders), then review and investigate their composition and function. Gelatinous tissues from nine species were analysed for water content (96.53 ± 1.78% s.d.), ionic composition, osmolality, protein (0.39 ± 0.23%), lipid (0.69 ± 0.56%) and carbohydrate (0.61 ± 0.28%). Results suggest that gelatinous tissues are mostly extracellular fluid, which may allow animals to grow inexpensively. Further, almost all gelatinous tissues floated in cold seawater, thus their lower density than seawater may contribute to buoyancy in some species. We also propose a new hypothesis: gelatinous tissues, which are inexpensive to grow, may sometimes be a method to increase swimming efficiency by fairing the transition from trunk to tail. Such a layer is particularly prominent in hadal snailfishes (Liparidae); therefore, a robotic snailfish model was designed and constructed to analyse the influence of gelatinous tissues on locomotory performance. The model swam faster with a watery layer, representing gelatinous tissue, around the tail than without. Results suggest that the tissues may, in addition to providing buoyancy and low-cost growth, aid deep-sea fish locomotion. © 2017 The Authors

    A culture-independent and culture-dependent study of the bacteria community from the bedrock soil interface

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    In nutrient limited soils, minerals constitute a major reservoir of bio-essential elements. Consequently, the release of nutritive elements during weathering is crucial. Bacteria have been shown to enhance weathering rates; however, there has been limited work that has focused on the bacterial weathering of bedrock or parent rock, which are the major sources of minerals, in nutrient limiting soils. In this study, both a culture-independent and culture-dependent approach was used to study the bacterial community at the interface between basaltic bedrock and nutrient limiting soil in Cadiar Idris region of Snowdonia National Park, United Kingdom. High throughput sequencing method, Ion Torrent, was used to characterise the bacterial community, which generated over 250,000 sequences. Taxonomical assignment demonstrated that approximately 50% (125,000 sequences) of the community consisted of the orders Actinomycetales, Burkholderiales, Clostridales, Bacillales, Rhizobiales and Acidobacterium, with unclassified sequences representing 44% ± 1.46% (110,000 ± 3650). Bacteria belonging to the genera Serratia, Pseudomonas, Bacillus, Paenibacillus, Chromobacterium, Janthinobacterium, Burkholderia and Arthrobacter, were isolated from the sample site. All of the isolates were able to grow in a minimal growth medium, which contained glucose, ammonium chloride with basalt as the sole source of bio-essential elements. Seventy percent of the isolates significantly enhanced basalt dissolution (p < 0.05). The rate of dissolution correlated to the production of oxalic acid and acidification of the growth medium. The findings of this work suggest that at the interface between bedrock and soil heterotrophic members of the bacterial community can enhance weathering, an essential part of biogeochemical cycling in nutrient limiting soil

    A low density of 0.8 g/cc for the Trojan binary asteroid 617 Patroclus

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    The Trojan population consists of two swarms of asteroids following the same orbit as Jupiter and located at the L4 and L5 Lagrange points of the Jupiter-Sun system (leading and following Jupiter by 60 degrees). The asteroid 617 Patroclus is the only known binary Trojan (Merline et al. 2001). The orbit of this double system was hitherto unknown. Here we report that the components, separated by 680 km, move around the system centre of mass, describing roughly a circular orbit. Using the orbital parameters, combined with thermal measurements to estimate the size of the components, we derive a very low density of 0.8 g/cc. The components of Patroclus are therefore very porous or composed mostly of water ice, suggesting that they could have been formed in the outer part of the solar system.Comment: 10 pages, 3 figures, 1 tabl

    In the Murine and Bovine Maternal Mammary Gland Signal Transducer and Activator of Transcription 3 is Activated in Clusters of Epithelial Cells around the Day of Birth

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    Signal transducers and activators of transcription (STAT) proteins regulate mammary development. Here we investigate the expression of phosphorylated STAT3 (pSTAT3) in the mouse and cow around the day of birth. We present localised colocation analysis, applicable to other mammary studies requiring identification of spatially congregated events. We demonstrate that pSTAT3-positive events are multifocally clustered in a non-random and statistically significant fashion. Arginase-1 expressing cells, consistent with macrophages, exhibit distinct clustering within the periparturient mammary gland. These findings represent a new facet of mammary STAT3 biology, and point to the presence of mammary sub-microenvironments.</p

    Adrenoceptors in GtoPdb v.2023.1

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    The nomenclature of the Adrenoceptors has been agreed by the NC-IUPHAR Subcommittee on Adrenoceptors [64, 194]. Adrenoceptors, &#945;1 The three &#945;1-adrenoceptor subtypes &#945;1A, &#945;1B and &#945;1D are activated by the endogenous agonists (-)-adrenaline and (-)-noradrenaline. -(-)phenylephrine, methoxamine and cirazoline are agonists and prazosin and doxazosin antagonists considered selective for &#945;1- relative to &#945;2-adrenoceptors. [3H]prazosin and [125I]HEAT (BE2254) are relatively selective radioligands. S(+)-niguldipine also has high affinity for L-type Ca2+ channels. Fluorescent derivatives of prazosin (Bodipy FLprazosin- QAPB) are used to examine cellular localisation of &#945;1-adrenoceptors. &#945;1-Adrenoceptor agonists are used as nasal decongestants; antagonists to treat symptoms of benign prostatic hyperplasia (alfuzosin, doxazosin, terazosin, tamsulosin and silodosin, with the last two compounds being &#945;1A-adrenoceptor selective and claiming to relax bladder neck tone with less hypotension); and to a lesser extent hypertension (doxazosin, terazosin). The &#945;1- and &#946;2-adrenoceptor antagonist carvedilol is used to treat congestive heart failure, although the contribution of &#945;1-adrenoceptor blockade to the therapeutic effect is unclear. Several anti-depressants and anti-psychotic drugs are &#945;1-adrenoceptor antagonists contributing to side effects such as orthostatic hypotension. Adrenoceptors, &#945;2 The three &#945;2-adrenoceptor subtypes &#945;2A, &#945;2B and &#945;2C are activated by (-)-adrenaline and with lower potency by (-)-noradrenaline. brimonidine and talipexole are agonists and rauwolscine and yohimbine antagonists selective for &#945;2- relative to &#945;1-adrenoceptors. [3H]rauwolscine, [3H]brimonidine and [3H]RX821002 are relatively selective radioligands. There are species variations in the pharmacology of the &#945;2A-adrenoceptor. Multiple mutations of &#945;2-adrenoceptors have been described, some associated with alterations in function. Presynaptic &#945;2-adrenoceptors regulate many functions in the nervous system. The &#945;2-adrenoceptor agonists clonidine, guanabenz and brimonidine affect central baroreflex control (hypotension and bradycardia), induce hypnotic effects and analgesia, and modulate seizure activity and platelet aggregation. clonidine is an anti-hypertensive (relatively little used) and counteracts opioid withdrawal. dexmedetomidine (also xylazine) is increasingly used as a sedative and analgesic in human [33] and veterinary medicine and has sympatholytic and anxiolytic properties. The &#945;2-adrenoceptor antagonist mirtazapine is used as an anti-depressant. The &#945;2B subtype appears to be involved in neurotransmission in the spinal cord and &#945;2C in regulating catecholamine release from adrenal chromaffin cells. Although subtype-selective antagonists have been developed, none are used clinically and they remain experimental tools. Adrenoceptors, &#946; The three &#946;-adrenoceptor subtypes &#946;1, &#946;2 and &#946;3 are activated by the endogenous agonists (-)-adrenaline and (-)-noradrenaline. Isoprenaline is selective for &#946;-adrenoceptors relative to &#945;1- and &#945;2-adrenoceptors, while propranolol (pKi 8.2-9.2) and cyanopindolol (pKi 10.0-11.0) are relatively selective antagonists for &#946;1- and &#946;2- relative to &#946;3-adrenoceptors. (-)-noradrenaline, xamoterol and (-)-Ro 363 show selectivity for &#946;1- relative to &#946;2-adrenoceptors. Pharmacological differences exist between human and mouse &#946;3-adrenoceptors, and the 'rodent selective' agonists BRL 37344 and CL316243 have low efficacy at the human &#946;3-adrenoceptor whereas CGP 12177 (low potency) and L 755507 activate human &#946;3-adrenoceptors [88]. &#946;3-Adrenoceptors are resistant to blockade by propranolol, but can be blocked by high concentrations of bupranolol. SR59230A has reasonably high affinity at &#946;3-adrenoceptors, but does not discriminate between the three &#946;- subtypes [332] whereas L-748337 is more selective. [125I]-cyanopindolol, [125I]-hydroxy benzylpindolol and [3H]-alprenolol are high affinity radioligands that label &#946;1- and &#946;2- adrenoceptors and &#946;3-adrenoceptors can be labelled with higher concentrations (nM) of [125I]-cyanopindolol together with &#946;1- and &#946;2-adrenoceptor antagonists. Fluorescent ligands such as BODIPY-TMR-CGP12177 can be used to track &#946;-adrenoceptors at the cellular level [8]. Somewhat selective &#946;1-adrenoceptor agonists (denopamine, dobutamine) are used short term to treat cardiogenic shock but, chronically, reduce survival. &#946;1-Adrenoceptor-preferring antagonists are used to treat cardiac arrhythmias (atenolol, bisoprolol, esmolol) and cardiac failure (metoprolol, nebivolol) but also in combination with other treatments to treat hypertension (atenolol, betaxolol, bisoprolol, metoprolol and nebivolol) [528]. Cardiac failure is also treated with carvedilol that blocks &#946;1- and &#946;2-adrenoceptors, as well as &#945;1-adrenoceptors. Short (salbutamol, terbutaline) and long (formoterol, salmeterol) acting &#946;2-adrenoceptor-selective agonists are powerful bronchodilators used to treat respiratory disorders. Many first generation &#946;-adrenoceptor antagonists (propranolol) block both &#946;1- and &#946;2-adrenoceptors and there are no &#946;2-adrenoceptor-selective antagonists used therapeutically. The &#946;3-adrenoceptor agonist mirabegron is used to control overactive bladder syndrome. There is evidence to suggest that &#946;-adrenoceptor antagonists can reduce metastasis in certain types of cancer [197]

    The Grizzly, February 28, 2002

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    Doug Farah Pays a Visit to Ursinus • Ursinus Students in Who\u27s Who List • Mysterious Rash Hits School Children Across the Country • Welcome to the Real World • Xanax Abuse • Controversy in the World of Figure Skating • Opinions: Spring Break; Sprinklers: Where are They?; Italy for a Semester • Experience the Beauty of Spring at the Philadelphia Flower Show • Marisol: A Different but Successful Performance at Ursinus College • Some Hot Tips for an Exciting and Safe Spring Break in Sunny Mexico • Track Team\u27s Results from Haverford • Men\u27s Basketball Falls Short at F&M • Men\u27s Rugby Team Admitted to Eastern Pennsylvania Rugby Union • Kings of the Court • Aivazian says Bye, Bye, Bye to the Division I Competition at UPenn • UC Swimmers Turn Up the Heat in the Water at the 2002 CC Championship Meethttps://digitalcommons.ursinus.edu/grizzlynews/1509/thumbnail.jp
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