Delivery cerebral

Decreased cerebral blood flow, resulting from acute arterial occlusion, reduces oxygen and glucose delivery to brain tissue with subsequent lactic acid production, blood-brain barrier breakdown, inflammation, sodium and calcium pump dysfunction, glutamate release, intracellular calcium influx, free-radical generation, and finally membrane and nucleic acid breakdown and cell death. The degree of cerebral blood flow reduction following arterial occlusion is not uniform. Tissue at the... 

Increased cerebral metabolism increased cerebral oxygen delivery. 

Lee, P.A., A.L. Sylvia, and C.A. Piantdosi. 1988. Cyanide-related changes in cerebral 02 delivery and metabolism in fluorocarbon-circulated rats. Toxicol. Appl. Pharmacol. 94 34-44. 

The density of cerebral capillaries, especially in the cortical grey matter, is very high with mean distances of 40 /xm. The capillary network has a total length of 600-650 km, the mean velocity of the blood flow is below 0.1 cm/s, and the luminal surface extends to 15-30 m2. Thus the blood-brain barrier represents an important surface for potential drug delivery besides gut (30CM100 m2), lung (70-120 m2), or skin (1.8 m2) [24-26, 33-37],... 

Brain delivery of steroid hormones is also of interest to medicinal chemists. Again, most data available on CDSs of steroids pertain to rates of oxidation of the dihydropyridine carrier, to blood and brain concentrations, and to pharmacological activities. The latter can then be taken as proof of efficient cerebral hydrolysis of the pyridinium metabolite. Thus, the dihydrotrigonelline carrier allowed good brain delivery of estradiol and some other estrogens [181][182],... 

IWo days after a full-term normal delivery, a neonate begins to hyperventilate, develops hypothermia and cerebral edema, and becomes comatose. Urinalysis reveals high levels of glutamine and orotic acid. The BUN is below normal. Which enzyme is most likely to be deficient in this child ... 

Figure 2.9. Differential pharmacological effect elicited by vector-mediated delivery of a VIP analogue. The organ blood flow in brain and salivary gland was measured in conscious rats after i.v. administration of vehicle (saline), the brain delivery vector OX26-SA, the VIP peptide alone, or the chimeric peptide. While cerebral blood flow increased in the chimeric peptide group by 60% compared to the saline control, the increase in salivary gland blood flow seen with the peptide alone was abolished by coupling to the vector. The VIP analogue was biotinylated with a non-cleavable 14-atom spacer (biotin-XX) for coupling to the vector. Data from reference [95].

Fluorinated gases (e.g., trifluoromethane (FC-23) and chlorofluoromethane (FC-22)) have been used to examine cerebral blood flow based on inflow and outflow kinetics, sometimes with pulsed delivery to facilitate compartmental analysis [401,402], The observation that HFB clears from tumors over a period of hours suggests this could provide insight into tissue perfusion [224,266],... 

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