- Physical Instability of Peptides and Proteins

The epoch of nanotechnology has authorized novel investigation strategies in the area of drug delivery. Liposomes are attractive biomimetic nanocarriers characterized by their biocompatibility, high loading capacity, and their ability to reduce encapsulated drug toxicity. Nevertheless, various limitations including physical instability, lack of site specificity, and low targeting abilities have impeded the use of solo liposomes. Metal nanocarriers are emerging moieties that can enhance the therapeutic activity of many drugs with improved release and targeted potential, yet numerous barriers, such as colloidal instability, cellular toxicity, and poor cellular uptake, restrain their applicability in vivo. The empire of nanohybrid systems has shelled to overcome these curbs and to combine the criteria of liposomes and metal nanocarriers for successful theranostic delivery. Metallic moieties can be embedded or functionalized on the liposomal systems. The current review sheds light on different liposomal-metal nanohybrid systems that were designed as cellular bearers for therapeutic agents, delivering them to their targeted terminus to combat one of the most widely recognized diseases, cancer.

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Physical instability and weather prediction — two examples using a new finite difference scheme

Proceedings of the Fifth International Conference on Numerical Methods in Fluid Dynamics June 28 – July 2, 1976 Twente University, Enschede - Lecture Notes in Physics ◽

10.1007/3-540-08004-x_348 ◽

1976 ◽

pp. 415-420

Author(s):

J. Steppeler

Keyword(s):

Finite Difference ◽

Difference Scheme ◽

Finite Difference Scheme ◽

Weather Prediction ◽

Physical Instability

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Chemical deterioration and physical instability of foods and beverages

Food and Beverage Stability and Shelf Life ◽

10.1533/9780857092540.1.29 ◽

2011 ◽

pp. 29-62 ◽

Cited By ~ 5

Author(s):

F. Kong ◽

R.P. Singh

Keyword(s):

Physical Instability

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Physicochemical stability of pembrolizumab admixture solution in normal saline intravenous infusion bag

Journal of Oncology Pharmacy Practice ◽

10.1177/1078155219868516 ◽

2019 ◽

Vol 26 (3) ◽

pp. 641-646 ◽

Cited By ~ 2

Author(s):

Prakash Sundaramurthi ◽

Sean Chadwick ◽

Chakravarthy Narasimhan

Keyword(s):

Normal Saline ◽

Intravenous Infusion ◽

Room Temperature ◽

Extended Period ◽

End User ◽

Physicochemical Stability ◽

Diluted Solution ◽

Aseptic Conditions ◽

Physical Instability

Introduction Pembrolizumab is an anti-PD-1 monoclonal antibody, approved and under development for numerous indications in oncology. It is available as either lyophilized powder for reconstitution or ready-to-use solution. Both are required to be diluted in saline or dextrose solution prior to intravenous infusion. After dilution, the recommendation per summary of product characteristics is 24 h at 2–8℃ and 6 h at room temperature. The purpose of this study was to investigate the physicochemical stability of pembrolizumab diluted solution (1 mg/mL) at both refrigerated and room temperature conditions for an extended period. Methods Under aseptic conditions, pembrolizumab was diluted in 250 mL of saline injection in polyolefin bags to obtain the final protein concentration of 1 mg/mL. Thus, prepared bags were then stored at either 5℃ ± 3℃, refrigerator exposing the product to ambient light or room temperature (20℃ ± 3℃) on the benchtop. Results Using several analytical methods, it was demonstrated that pembrolizumab solution for infusion, diluted in normal saline can be stored in polyolefin infusion bags for at least 1 week at 5℃ or RT with no evidence of chemical or physical instability. No aggregation was observed. Conclusion Thus, the practical use of aseptically prepared diluted pembrolizumab in saline can be safely extended to optimize the workload of centralized preparation units and to minimize costs. However, it is the responsibility of the end-user to maintain overall quality of prepared admixture solution that is administered to patient, by following aseptic compounding process as recommended in the packaging insert.

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Mechanically patterning the embryonic airway epithelium

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1504102112 ◽

2015 ◽

Vol 112 (30) ◽

pp. 9230-9235 ◽

Cited By ~ 49

Author(s):

Victor D. Varner ◽

Jason P. Gleghorn ◽

Erin Miller ◽

Derek C. Radisky ◽

Celeste M. Nelson

Keyword(s):

Airway Epithelium ◽

Reaction Diffusion ◽

Spatial Patterning ◽

Molecular Precursors ◽

Physical Mechanisms ◽

And Function ◽

Molecular Signals ◽

Biological Patterns ◽

Epithelial Growth ◽

Physical Instability

Collections of cells must be patterned spatially during embryonic development to generate the intricate architectures of mature tissues. In several cases, including the formation of the branched airways of the lung, reciprocal signaling between an epithelium and its surrounding mesenchyme helps generate these spatial patterns. Several molecular signals are thought to interact via reaction-diffusion kinetics to create distinct biochemical patterns, which act as molecular precursors to actual, physical patterns of biological structure and function. Here, however, we show that purely physical mechanisms can drive spatial patterning within embryonic epithelia. Specifically, we find that a growth-induced physical instability defines the relative locations of branches within the developing murine airway epithelium in the absence of mesenchyme. The dominant wavelength of this instability determines the branching pattern and is controlled by epithelial growth rates. These data suggest that physical mechanisms can create the biological patterns that underlie tissue morphogenesis in the embryo.

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Evidence that more than a third of Paleozoic articulate brachiopod genera (Strophomenata) lived infaunally

Paleobiology ◽

10.1017/pab.2020.29 ◽

2020 ◽

Vol 46 (3) ◽

pp. 405-433

Author(s):

Steven M. Stanley

Keyword(s):

Late Paleozoic ◽

Physical Instability

AbstractThe Strophomenata, which includes two large orders, the Strophomenida and Productida, is the largest group of Paleozoic brachiopods. Nearly all uncemented strophomenatans possessed an unusual concave brachial valve. Most of these have been considered to have lived epifaunally, but had they rested on the seafloor, not only would they have faced intense predation, but their physical instability would have been fatal. I conclude that nearly all strophomenatans, like similar concavo-convex pectinid bivalves, lived infaunally by ejecting water to create a pit into which they descended, to be protected by sediment covering the concave valve. Strophomenatans have been discovered with this sediment preserved in place. If exhumed and turned upside down, a strophomenatan could have righted itself by squirting water. Many productides had anchoring spines, and some had hinge areas with stabilizing flanges. Small spines on the brachial valves of some productides served to trap disguising sediment. Evolutionary loss of hinge teeth within both the Strophomenida and Productida reduced the friction of valve clapping. Partly because of their slender shape, strophomenides were typically more vulnerable to exhumation than productides. Strophomenides also ejected water less effectively than productides and would have been less adept at righting themselves. The virtual disappearance of the strophomenides during the Devonian can be attributed to their vulnerability to intensifying benthic bulldozing and predation. The success of the productides during the late Paleozoic can be attributed to their relatively deep sequestration in the sediment and ability to right themselves and reburrow effectively when exhumed and overturned.

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Nanorod to quantum dot conversion in ZnO dispersions with co-surfactants

RSC Advances ◽

10.1039/c4ra05778c ◽

2015 ◽

Vol 5 (20) ◽

pp. 15154-15158 ◽

Cited By ~ 4

Author(s):

Niya Mary Jacob ◽

Tiju Thomas

Keyword(s):

Quantum Dot ◽

Chemically Induced ◽

Physical Instability

A chemically-induced nanorod to QD transition is achieved using co-surfactants. This is different from the physical instability driven transitions reported so far in nanowires and polymers. We propose a suitable mechanism for the observed phenomenon.

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Diversity of Archaea in Marine Sediments from Skan Bay, Alaska, Including Cultivated Methanogens, and Description of Methanogenium boonei sp. nov.

Applied and Environmental Microbiology ◽

10.1128/aem.01154-06 ◽

2006 ◽

Vol 73 (2) ◽

pp. 407-414 ◽

Cited By ~ 82

Author(s):

Melissa M. Kendall ◽

George D. Wardlaw ◽

Chin F. Tang ◽

Adam S. Bonin ◽

Yitai Liu ◽

...

Keyword(s):

Marine Sediments ◽

Type Strain ◽

Multidisciplinary Approach ◽

Archaeal Community ◽

Cold Seeps ◽

Atmospheric Methane ◽

Important Process ◽

A New Species ◽

Culture Dependent ◽

Physical Instability

ABSTRACT Methanogenesis in cold marine sediments is a globally important process leading to methane hydrate deposits, cold seeps, physical instability of sediment, and atmospheric methane emissions. We employed a multidisciplinary approach that combined culture-dependent and -independent analyses with geochemical measurements in the sediments of Skan Bay, Alaska (53°N, 167°W), to investigate methanogenesis there. Cultivation-independent analyses of the archaeal community revealed that uncultivated microbes of the kingdoms Euryarchaeota and Crenarchaeota are present at Skan Bay and that methanogens constituted a small proportion of the archaeal community. Methanogens were cultivated from depths of 0 to 60 cm in the sediments, and several strains related to the orders Methanomicrobiales and Methanosarcinales were isolated. Isolates were psychrotolerant marine-adapted strains and included an aceticlastic methanogen, strain AK-6, as well as three strains of CO2-reducing methanogens: AK-3, AK7, and AK-8. The phylogenetic positions and physiological characteristics of these strains are described. We propose a new species, Methanogenium boonei, with strain AK-7 as the type strain.

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