Behavior in vivo

Quastel M, Harrison R, Cicardi M, Alper C, Rosen F Behavior in vivo of normal and dysfunctional Cl inhibitor in normal subjects and patients with hereditary angioneurotic edema. J Chn Invest 1983 71 1041-1046. 

Isolation of conjugates containing molar ratios of 1 2 antibodyrdgA have resulted in greater cytotoxicity behavior in vivo (Ghetie et al., 1993). 

Size distribution plays a major role in the microbubble stability, behavior in vivo, and the microbubble acoustic response. The Rayleigh-Plesset equation which describes the microbubble response to pressure waves suggests that ultrasound scattering is proportional to the sixth power of the microbubble diameter [46]. It is not possible, however, to inject large bubbles (e.g., 0.1 or 1 mm in diameter) in the bloodstream, because they would be immediately lodged in the vasculature as emboli, severely limiting the blood flow. Fortunately, microbubbles with the size of several micrometers are still quite echogenic in the ultrasound... 

Kawashima, Y., et al. 1991. Preparation of multiple unit hollow microspheres (microballons) with acrylic resin containing tranilast and their drug release characteristics in vitro) and floating behavior in vivo). J Control Release 16 279... 

Prolonged and unnecessary enzymatic treatment, i.e., trypsinization of tumor cells, can also alter their survival and metastatic behavior in vivo. Moreover, viability tests (trypan blue exclusion) and even plating efficiency in vitro do not predict or correlate with the in vivo biological behavior of trypsinized cells. 

Yagel, S., Khokha, R., Denhardt, D. T., Kerbel, R. S., Parhar, R. S. and Lala, P. K. (1989). Mechanisms of cellular invasiveness a comparison of amnion invasion in vitro and metastatic behavior in vivo. J. Natl. Cancer Inst. 57,768-775. 

Although conventional dissolution tests try to reflect either one or a combination of the following factors pH, ionic strength of GI fluid, and the agitation intensity (motility) of the GI tract, methods that show the effect of a mechanical destructive force on drug release are relatively limited. Therefore, in vitro studies using the conventional methods are sometimes unable to predict drug behavior in vivo, particularly in the fed state. To estimate this influence, a multicompartmental, dynamic, computer-controlled system that simulates... 

Although these data leave much to be desired, they are probably the best indication available of what normal and pathological ranges are likely to be. The data suggest that the appropriate range of variation to mimic steady-state kinetic behavior in vivo is typically an order of magnitude or less, and that kinetic behavior exhibited in vitro, when concentration variables are varied over more extreme... 

Research in the area of nanotechnology has been rapidly advancing that we find that the tools either lack sensitivity or resolution that is required to effectively characterize very low signals. Characterization of the various properties such as topography, morphology, mechanical, and porosity of biomaterials before their use is very critical and important so that we can predict their behavior in vivo. However, characterization tools have improved over the past couple of decades, and collectively, we have been able to image and understand not only the surface of materials but also their properties. For example, the atomic force microscope provides atomic-scale surface data, while the scanning electron microscope provides micro- and nanoscale surface data, and the nanoscale data about the internal structure of materials can be obtained from transmission electron microscope. With this information and with data on the mechanical properties, wettability, porosity, etc., we would be able to understand the surfaces of materials and how they would behave in vitro and in vivo. 

A W/O/W multiple emulsion containing rifampicin as encapsulant was coated with an o-palmi(oyl derivative of mannan to assess its toxicity in vitro and its distribution behavior in vivo. A significant enhancement in lung uptake and a decreased internalization by spleen was noticed. The multiple emulsion was found to be nontoxic (125). 

Tissues such as bone, cartilage, and myocardium possess highly specialized structures and compositions that provide unique mechanical and transport properties. Therefore, to reconstruct a functional engineered tissue after damage, due to injury, disease, or aging, it is necessary to understand how these specialized structures affect cell behavior in vivo, and use this information to direct the design of substitute tissues and organs. 

Lab-on-a-Chip Devices for Particle and Cell Separation, Fig. 8 Leukocyte autoseparation device. By imitating leukocytes behavior in vivo, the... 

In order to test the valve behavior in vivo, two prototypes were implanted in a sheep model (IMM, Paris) in mitral position. The procedure was done under extra-corporeal bypass circulation. The first animal remained alive for 12 h after implantation with satisfactory valve function. The death ensuing came from intrathoracic bleeding. However, the absence of thrombosis on both sides of the fabric surface could be observed once the device was explanted (see Fig. 16.38). The second animal was still alive after 8 weeks... 

The effects shown by contacting the foreign surface in the coagulation of blood have been further complicated by the use of the kinds of polymers in some investigations with resultant scattering of data ". In addition, we studied the functional effects of exposure of blood coagulation factors and platelets to the surfaces of synthetic polymers from the viewpoint that extrapolation from the behaviors in vitro to their antithrombogenic behaviors in vivo would allow prediction of clinical usefulness of candidate materials. /... 

Semple SC, Chonn A, CuUis PR. Interactions of liposomes and lipid-based carrier systems with blood proteins relation to clearance behavior in vivo. Adv Drug Deliv Rev 1998 32 3-17. 

Since most oral AChEIs exhibit a dose-dependent relationship with undesirable cholinergic adverse effects, researchers have in recent years been focusing on slow-release administration to minimize the fluctuations in plasma concentration [67, 68]. Ye and coworkers have developed transdermal patches containing 4 mg of hupA with the average daily dose of 0.456 mg absorbed [68]. A recent clinical study on 30 healthy volunteers revealed that the transdermal administration provided continuous drug delivery over 120 h and the pharmacokinetic behavior in vivo... 

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