Primate studies

In addition, a recent primate study reported that dietary consumption of soy infant formula reduced the neonatal testosterone surge and increased Leydig cell numbers in the testes of male marmosets. However, the longterm effects on the fertility of the animals has not been determined, and the health implications of these findings for humans are unclear (Sharpe et al,... 

Lloyd concurs and adds the patient s social entirety as well, citing a series of studies that show that ecological factors also matter, most surprisingly the income gradient of a society. What matters is not simply the difference between the richest and poorest people in some absolute sense, but the relative difference in their own society. People living in a relatively poor society can lead healthier lives than people living in a richer society if the difference between the richest and the poorest in their society is less. What really matters is how much poorer poor people are in a society relative to the richest people. However, Lloyd s later appeal to data drawn from primate studies might lead some to cry reductionism . The human species is unique. No inferences can be made from other species, even primate species, to us. 

Many primate studies are on human antibodies that cannot be tested with other species due to problems of antigenicity. 

Doses should be selected that are reasonable multiples of the proposed therapeutic dose to be employed, especially since in many cases the amount of material available for testing may be limited and not available in Kg amounts. Preclinical rodent or primate studies should merely provide the flags to monitor during Phase I clinical trials. Reason should prevail, not only in the selection of methods and models for assessing the potential toxicity of the new agents, but also in the use of these data for extrapolation to humans. Whether U.S. industry succeeds or fails in the biotechnology arena will depend on the quick resolution of issues such as... 

Effects on blood pressure, heart rate, lead II ECG, core body temperature, and locomotor activity can be explored using DataSciences telemetry implanted devices in rats, guinea-pigs, dogs, or primates. Effects on behavior can be captured on video using CCTV for dog and primate studies. Repeated administration and interaction studies can be performed. 

Efavirenz should be avoided during pregnancy because primate studies have shown it to be teratogenic at doses near therapeutic levels. Women of childbearing... 

It has been shown that 3 is biotransformed in a reaction catalysed by monoamine oxidase B to species that cause the selective degeneration of nigrostriatal neurons, giving rise to a Parkinsonian syndrome in man and other primates. Studies of this process have shown that the pyridinium salts 4 and 5 are involved, and that 4 undergoes spontaneous disproportionation to 5 and 3 5 is the putative ultimate neurotoxin. More recent studies have shown that 4 undergoes a spontaneous reaction in pH 7.4 buffer to give methylamine and a product identified as 6. 

Ingram DK, Cutler RG, Weindruch R, et al. Dietary restriction and aging The initiation of a primate study. J Gerontol 1990 45 B148-B163. 

Black A, Tilmont EM, Handy AM, Ingram DK, Roth GS, Lane MA. Calorie restriction reduces the incidence of proliferative disease Preliminary data from the NIA CR in nonhuman primate study. Gerontologist 2000 40 5. 

Although animal studies indicate transfer of A -THC into the milk, comparable research has not been done on humans. It is difficult to extrapolate from animal studies to humans. The only primates studied, squirrel monkeys, are known to metabolize A9-THC differently than humans. (15) In addition, lactating human mothers in the general population ingest both A9-THC and other cannabinoids (e.g., CBN, CBD) by smoking cannabis. Information is not currently available regarding either transfer of cannabinoids into the milk of lactating humans or the effects of maternal cannabis use on infant development. 

Early studies of T-20 (e.g., rat 6-month repeat-dose study) were inconclusive as to whether injection site inflammation was solely a result of the procedure of the drug or some combination of the two. In retrospective review of data, it appears that inflammation is, at least in part, a reaction to the drug. It is irrelevant that microscopic evidence of an injection site reaction in primates was not common until week 17. In the same (9-month primate) study, increased eosinophils (compared with controls) were measured at 3 months (earliest postdosing hematological measurement), and inflammatory response were evident in the spleens (increased germinal centers and lymphocytic proliferation) and thymuses (cortical lymphocytic depletion) at 3 months. In the 28-day, repeat-dose primate study antibodies to T-20 were detected at day 7. Thus inflammation, while not clearly evident macroscopically until week 17 in the 9-month study, was microscopically evident earlier on... 

The following section describes protocols for evaluating both dependence and abuse. For reasons of homogeneity with the other procedures presented above, only protocols in the rat will be presented. Although results in the rat are generally similar to those obtained in non-human primates, the regulatory authorities, in particular the FDA, prefer primate studies for abuse evaluation because of a presumed increased predictability to man. The active doses and pharmacokinetics are likely to be closer between human and non-human primates, as are the kinds of overt behavioral effects observed. 

Despite encouraging preclinical results with Group I agonists, clinical data remain lacking. Further, group I receptors have a markedly different cellular distribution in primates than rodents (Muly et al., 2003 Paquet and Smith, 2003). Primate studies and eventual clinical trials therefore will be needed to validate this target for the treatment of neuropsychiatric disorders. Nevertheless, the preclinical efficacy of these compounds remains encouraging for eventual therapeutic utility. 

Similar results have been forthcoming from primate studies. Thus, D1 receptor antagonists administered iontophoretically to the PFC enhance, rather than impair, stimulus processing by single units in delayed saccade paradigms (Williams and Goldman-Rakic,... 

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