scholarly journals Homolog comparisons further reconcile in vitro and in vivo correlations of protein activities by revealing over‐looked physiological factors

2019 ◽  
Vol 28 (10) ◽  
pp. 1806-1818 ◽  
Author(s):  
Sudheer Tungtur ◽  
Kristen M. Schwingen ◽  
Joshua J. Riepe ◽  
Chamitha J. Weeramange ◽  
Liskin Swint‐Kruse
Keyword(s):  
Physiological Factors

scholarly journals Advances in Photoacoustic Noninvasive Glucose Testing

1999 ◽  
Vol 45 (9) ◽  
pp. 1587-1595 ◽  
Author(s):  
Hugh A MacKenzie ◽  
Helen S Ashton ◽  
Stephen Spiers ◽  
Yaochun Shen ◽  
Scott S Freeborn ◽  
...  
Keyword(s):  
Glucose Measurement ◽  
Oral Glucose ◽  
Physiological Factors ◽  
Glucose Testing ◽  
In Vivo Experiments ◽  
In Vitro Measurements ◽  
Clinical Measurements ◽  
Blood Analytes

Abstract We report here on in vitro and in vivo experiments that are intended to explore the feasibility of photoacoustic spectroscopy as a tool for the noninvasive measurement of blood glucose. The in vivo results from oral glucose tests on eight subjects showed good correlation with clinical measurements but indicated that physiological factors and person-to-person variability are important. In vitro measurements showed that the sensitivity of the glucose measurement is unaffected by the presence of common blood analytes but that there can be substantial shifts in baseline values. The results indicate the need for spectroscopic data to develop algorithms for the detection of glucose in the presence of other analytes.

Factors affecting the antioxidant potential and health benefits of plant foods

2012 ◽  
Vol 92 (6) ◽  
pp. 1101-1111 ◽  
Author(s):  
Hongyan Li ◽  
Rong Tsao ◽  
Zeyuan Deng
Keyword(s):  
Antioxidant Activities ◽  
Health Benefits ◽  
Antioxidant Potential ◽  
Physiological Factors ◽  
Factors Affecting ◽  
Plant Foods ◽  
Post Harvest ◽  
Different Types

Li, H., Tsao, R. and Deng, Z. 2012. Factors affecting the antioxidant potential and health benefits of plant foods. Can. J. Plant Sci. 92: 1101–1111. Phytochemicals, such as carotenoids, phenolics and glucosinolates, in plants and plant-based foods are able to reduce the incidence of non-communicable diseases such as cardiovascular diseases, diabetes, stroke and different types of cancer due to their antioxidant potential. A brief summary of the in vitro and in vivo evidence and how post-harvest storage and processing conditions can affect the health benefits is presented in this review. Genetic, environmental conditions and physiological factors may modify the composition and amounts of these compounds present in plants, thus affecting the in vitro antioxidant activities. Such changes in combination with degradations after digestion can significantly affect the bioaccessibility and bioavailability of phytochemicals. The main objective of this review is to provide updated information on the effects of various factors such as genetics, environment, post-harvest storage and processing on the bioactive components, and knowledge of these factors can lead to multidisciplinary strategies to maximise the bioavailability and health potential of foods.

scholarly journals Polyphenols and Their Effects on Muscle Atrophy and Muscle Health

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4887
Author(s):  
Takeshi Nikawa ◽  
Anayt Ulla ◽  
Iori Sakakibara
Keyword(s):  
Muscle Atrophy ◽  
Polyphenolic Compounds ◽  
Bioactive Molecules ◽  
In Vivo Studies ◽  
Skeletal Muscle Atrophy ◽  
Physiological Factors ◽  
Muscle Disorders ◽  
Muscle Health

Skeletal muscle atrophy is the decrease in muscle mass and strength caused by reduced protein synthesis/accelerated protein degradation. Various conditions, such as denervation, disuse, aging, chronic diseases, heart disease, obstructive lung disease, diabetes, renal failure, AIDS, sepsis, cancer, and steroidal medications, can cause muscle atrophy. Mechanistically, inflammation, oxidative stress, and mitochondrial dysfunction are among the major contributors to muscle atrophy, by modulating signaling pathways that regulate muscle homeostasis. To prevent muscle catabolism and enhance muscle anabolism, several natural and synthetic compounds have been investigated. Recently, polyphenols (i.e., natural phytochemicals) have received extensive attention regarding their effect on muscle atrophy because of their potent antioxidant and anti-inflammatory properties. Numerous in vitro and in vivo studies have reported polyphenols as strongly effective bioactive molecules that attenuate muscle atrophy and enhance muscle health. This review describes polyphenols as promising bioactive molecules that impede muscle atrophy induced by various proatrophic factors. The effects of each class/subclass of polyphenolic compounds regarding protection against the muscle disorders induced by various pathological/physiological factors are summarized in tabular form and discussed. Although considerable variations in antiatrophic potencies and mechanisms were observed among structurally diverse polyphenolic compounds, they are vital factors to be considered in muscle atrophy prevention strategies.

In vivo transport of calcium from healed Thiry-Vella fistulas in dogs

1962 ◽  
Vol 202 (1) ◽  
pp. 161-164 ◽  
Author(s):  
Carl F. Cramer ◽  
John Dueck
Keyword(s):  
Calcium Transport ◽  
Absorption Rate ◽  
Calcium Absorption ◽  
Carrier System ◽  
Absorption Data ◽  
Physiological Factors ◽  
Low Concentrations ◽  
Maximal Absorption

Calcium transport was studied in vivo in dogs by perfusing solutions of various calcium concentrations through healed jejunal Thiry-Vella fistulas. The method is simple, quantitative, and it avoids a number of difficulties of interpretation inherent in tracer and in vitro studies. At quite low concentrations the rate of Ca absorption was approximately proportional to Ca concentration, but at higher concentration the rate fell off continuously. Above 12.5 mm/liter the absorption rate remained constant at approximately 0.5 mm/hr. There was some variation from week to week in the same dog and between different dogs. However, in 30 runs on 10 dogs this maximum absorption rate averaged 18.5 ± 1.1 mg Ca/hr. Simultaneous administration of magnesium depressed maximum Ca absorption of 9.3 mg Ca/hr. The calcium absorption data conformed to the Michaelis-Menten equation. The approach to a maximal absorption rate with increasing Ca concentration, the Mg competition, and the conformity to the Michaelis-Menten kinetics all suggest that Ca is absorbed by a carrier system which may involve either active or facilitated transport. The method lends itself to studies of physiological factors which may affect calcium absorption.

scholarly journals A Literature Review of the Physicochemical, Physiological and Pharmaceutical Considerations in GIT Absorption of Drugs.

2017 ◽  
Vol II (I) ◽  
pp. 18-33
Author(s):  
Rabia Mazhar ◽  
Fariah Qaise ◽  
Sana Ali Zahra ◽  
Syeda Komal Fatima ◽  
Imran Khan
Keyword(s):  
Drug Development ◽  
Drug Absorption ◽  
Oral Route ◽  
Physiological Factors ◽  
New Drug ◽  
Physico Chemical ◽  
Key Factor ◽  
New Drug Development

Oral route of drug administration is the most common among all routes and hence their pharmacokinetic and pharmacodynamic factors are substantial to study. Among such factors, GIT absorption is the key factor in new drug development affecting the efficacy as well as safety of the drug. Different protocols have now been developed for the usage of in vitro also the in vivo as well as in situ methods in drug absorption determination. In this article, different mechanisms like passive diffusion, pore transport, ionic-mediated transport, endocytosis and other mechanisms involved in drug absorption will be explained. Moreover, different factors i.e. physico-chemical, pharmaceutical and physiological factors that affect drug absorption have been summarized as they play a significant role in the research studies for new drug development. Different absorption determining methods are also discussed.

Induction and Differentiation of Dental Epithelium in Vivo and in Vitro

1982 ◽  
Vol 40 ◽  
pp. 142-145
Author(s):  
E. J. Kollar
Keyword(s):  
Connective Tissue ◽  
Oral Mucosa ◽  
Basal Lamina ◽  
Functional Derivatives ◽  
Specific Source ◽  
Dental Epithelium ◽  
Connective Tissue Stroma

The differentiation and maintenance of many specialized epithelial structures are dependent on the underlying connective tissue stroma and on an intact basal lamina. These requirements are especially stringent in the development and maintenance of the skin and oral mucosa. The keratinization patterns of thin or thick cornified layers as well as the appearance of specialized functional derivatives such as hair and teeth can be correlated with the specific source of stroma which supports these differentiated expressions.

Ultrastructural Correlations between Clonal Human Tumor Colonies and in Vivo Neoplasms

1982 ◽  
Vol 40 ◽  
pp. 210-211
Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman
Keyword(s):  
Cultured Cells ◽  
Human Tumor ◽  
Cell Type ◽  
Tumor Mass ◽  
Initial Cell ◽  
Cloning Assay ◽  
Human Tumor Cloning ◽  
The Relationship

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.

Ultrastructure of melanocyte-keratinocyte interactions and pigment transfer in vitro

1978 ◽  
Vol 36 (2) ◽  
pp. 650-651
Author(s):  
Raul I. Garcia ◽  
Evelyn A. Flynn ◽  
George Szabo
Keyword(s):  
Direct Injection ◽  
Skin Pigmentation ◽  
Freeze Fracture ◽  
Pigment Granule ◽  
Time Lapse ◽  
Ultrastructural Level ◽  
Lanthanum Tracer ◽  
A Cell

Skin pigmentation in mammals involves the interaction of epidermal melanocytes and keratinocytes in the structural and functional unit known as the Epidermal Melanin Unit. Melanocytes(M) synthesize melanin within specialized membrane-bound organelles, the melanosome or pigment granule. These are subsequently transferred by way of M dendrites to keratinocytes(K) by a mechanism still to be clearly defined. Three different, though not necessarily mutually exclusive, mechanisms of melanosome transfer have been proposed: cytophagocytosis by K of M dendrite tips containing melanosomes, direct injection of melanosomes into the K cytoplasm through a cell-to-cell pore or communicating channel formed by localized fusion of M and K cell membranes, release of melanosomes into the extracellular space(ECS) by exocytosis followed by K uptake using conventional phagocytosis. Variability in methods of transfer has been noted both in vivo and in vitro and there is evidence in support of each transfer mechanism. We Have previously studied M-K interactions in vitro using time-lapse cinemicrography and in vivo at the ultrastructural level using lanthanum tracer and freeze-fracture.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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