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101.
Potential medicinal plants for wild chimpanzees have been studied in order to discover their physiologically active compounds. Tests of the physiological activity of 3 plant species—Vernonia amygdalina, Aspilia mossambicensis, andFicus exasperata—indicate that they contain a variety of active compounds. From one species,V. amygdalina, an antitumor agent and 2 possible antitumor promoters are identified. Furthermore, steroid glucosides were isolated as the bitter substances. These structurally new compounds are expected to exhibit a number of significant physiological activities. The chemical investigation of possible medicinal plants used by chimpanzees should be helpful in recovering naturally occurring compounds of medicinal significance for human use.  相似文献   
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Abstract

Eleven compounds were compared to ribavirin for their in vitro and in vivo inhibition of Punta Toro virus (PTV), a phlebovirus in the Bunyaviridae virus family.  相似文献   
105.
Previous studies on nonhuman primate maternal styles showed that variation in infant-directed behavior falls along two dimensions, traditionally labeled as protectiveness and rejection. We investigated maternal styles in rhesus (Macaca mulatta) and Japanese (M. fuscata) macaques living in analogous captive social groups, and correlated them with the levels of estrogen metabolites excreted in female feces during the perinatal period. We focally observed mother-infant pairs 3 hours per week during the first 12 weeks of infant life. We collected fecal samples twice a week from each mother, starting 4 weeks before delivery and ending 4 weeks after delivery. Three significant components were extracted by principal component analysis from 15 different infant directed behaviors, each reflecting a different aspect of mothering style: rejection is correlated with behavioral measures of maternal opposition to contact; protectiveness is correlated with maternal solicitude; and independence is correlated with time in contact, grooming and cradling. Levels of estrogen metabolites are significantly correlated to rejection but not to protectiveness or independence, indicating that, in nonhuman primates, individual endocrine changes related to maternal behavior might specifically affect the timing of contact interruption.  相似文献   
106.

The callitrichids are non-human primates that feed on insects and plant matter in nature, but in captivity, they are fed mostly an artificial diet containing amounts of gluten, in their toxic forms in items such as wheat, barley and rye. The aim of this research was to estimate the blood β-defensin and Toll like receptor 5 (TLR5) gene expressions and to analyze the stool consistency (firm, soft, diarrheic) in Leontocebus fuscicollis raised in captivity. Blood samples of animals under gluten-free and gluten diets were collected and their fecal output quality was periodically monitored and classified during the course of the study. Gene expression was evaluated using real-time PCR. The stool consistencies of individuals fed a gluten diet were most frequently soft or diarrheic, while it was mostly normal in individuals fed a gluten-free diet. β-Defensin expression increased in individuals fed a gluten diet, but decreased after 15 days. Expression normalized between 30 and 45 days on a gluten-free diet. However, expression of the TLR5 gene did not change under a gluten diet. A gluten diet affects stool quality, and brings about an immediate increase in blood β-defensin expression in the beginning but decreases after 15 days.

  相似文献   
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The synthesis and pharmacology of 15 1-deoxy-Δ8-THC analogues, several of which have high affinity for the CB2 receptor, are described. The deoxy cannabinoids include 1-deoxy-11-hydroxy-Δ8-THC (5), 1-deoxy-Δ8-THC (6), 1-deoxy-3-butyl-Δ8-THC (7), 1-deoxy-3-hexyl-Δ8-THC (8) and a series of 3-(1′,1′-dimethylalkyl)-1-deoxy-Δ8-THC analogues (2, n=0–4, 6, 7, where n=the number of carbon atoms in the side chain−2). Three derivatives (1719) of deoxynabilone (16) were also prepared. The affinities of each compound for the CB1 and CB2 receptors were determined employing previously described procedures. Five of the 3-(1′,1′-dimethylalkyl)-1-deoxy-Δ8-THC analogues (2, n=1–5) have high affinity (Ki=<20 nM) for the CB2 receptor. Four of them (2, n=1–4) also have little affinity for the CB1 receptor (Ki=>295 nM). 3-(1′,1′-Dimethylbutyl)-1-deoxy-Δ8-THC (2, n=2) has very high affinity for the CB2 receptor (Ki=3.4±1.0 nM) and little affinity for the CB1 receptor (Ki=677±132 nM).
Scheme 3. (a) (C6H5)3PCH3+ Br, n-BuLi/THF, 65°C; (b) LiAlH4/THF, 25°C; (c) KBH(sec-Bu)3/THF, −78 to 25°C then H2O2/NaOH.  相似文献   
109.
Following the bite of an infective mosquito, malaria parasites first invade the liver where they develop and replicate for a number of days before being released into the bloodstream where they invade red blood cells and cause disease. The biology of the liver stages of malaria parasites is relatively poorly understood due to the inaccessibility of the parasites to sampling during this phase of their life cycle. Here we report the detection in blood and faecal samples of malaria parasite DNA throughout their development in the livers of mice and before the parasites begin their growth in the blood circulation. It is shown that parasite DNA derived from pre-erythrocytic stage parasites reaches the faeces via the bile. We then show that different primate malaria species can be detected by PCR in blood and faecal samples from naturally infected captive macaque monkeys. These results demonstrate that pre-erythrocytic parasites can be detected and quantified in experimentally infected animals. Furthermore, these results have important implications for both molecular epidemiology and phylogenetics of malaria parasites. In the former case, individuals who are malaria parasite negative by microscopy, but PCR positive for parasite DNA in their blood, are considered to be “sub-microscopic” blood stage parasite carriers. We now propose that PCR positivity is not necessarily an indicator of the presence of blood stage parasites, as the DNA could derive from pre-erythrocytic parasites. Similarly, in the case of molecular phylogenetics based on DNA sequences alone, we argue that DNA amplified from blood or faeces does not necessarily come from a parasite species that infects the red blood cells of that particular host.  相似文献   
110.
Fried B. and Huffman J. E. 1982. Excystation and development in the chick and on the chick chorioallantois of the metacercaria of Sphaeridiotrema globulus (Trematoda). International Journal for Parasitology12: 427–431. Encysted metacercariae of Sphaeridiotrema globulus were obtained from naturally infected Goniobasis virginica snails in Morris County, New Jersey, U.S.A. These metacercariae were successfully excysted within l h in an alkaline bile salts trypsin medium maintained at 41°C in the absence of acid pepsin pretreatment. Encysted metacercariae treated in 3% sodium bicarbonate produced successful infections in day-old domestic chicks and worms became ovigerous in the lower ileum by day 4. Excysted metacercariae transferred to the chorioallantois of 6–10-day-old chick embryos maintained at 41°C developed into ovigerous adults by day 4.  相似文献   
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