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The isolated ecosystem of Rubondo Island National Park, Tanzania is an interesting model site, inhabited by an assembly of primate species with various histories: two introduced primate species, Pantroglodytes (chimpanzee) and Colobus guereza (colobus), and a single indigenous species Chlorocebus aethiops pygerythrus (vervet monkey). Apart from important lessons for future introduction/re-introduction projects, Rubondo National Park offers a unique place to study the patterns of transmission of primate parasites and their host specificity. Blastocystis was detected using standard microscopy, together with PCR-based determination and the prevalence and subtype identification of Blastocystis was determined in each primate species. Subtype (ST) 1 was detected in all three Rubondo primate populations; ST2, ST3 and ST5 were found in colobus and vervet monkeys. All chimpanzee isolates of Blastocystis belonged exclusively to ST1, which formed a discrete group, suggesting that Rubondo chimpanzees are colonized by a single, host-specific Blastocystis strain that circulates among the members of the group. Phylogenetic analysis indicated that transmission of Blastocystis did not occur between Rubondo primate populations. Observed host specificity of Blastocystis provides a new understanding of the transmission and distribution of Blastocystis among sympatric hosts under natural conditions.

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Highly dense hexagonally ordered two-dimensional arrays of Si nanocrystals embedded in SiO(2) nanodots were fabricated on a silicon substrate by using a self-assembled porous anodic alumina thin film as a masking layer through which electrochemical oxidation of the Si substrate and ultralow energy Si implantation took place. After removal of the alumina film and high temperature annealing of the samples, hexagonally ordered Si nanocrystals embedded within SiO(2) nanodots were obtained, having sizes in the few tens of nanometer range. The fabricated ordered structures show significant potential for applications either in basic physics experiments or as building blocks for nanoelectronic and nanophotonic devices.

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We examined seasonal patterns of fruit availability, dietary quality, and group size in the descendants of an introduced chimpanzee population on Rubondo Island, Tanzania. The site has supported a free-ranging population without provisioning for 40 years. Our goals were to determine whether Rubondo chimpanzees experience periods of fruit shortage, and whether they respond to changes in fruit availability similarly to chimpanzees at endemic sites. We indexed the fruit availability of tree and liana species on transects stratified across three chimpanzee ranging areas. We used fecal analyses to evaluate seasonal changes in diet, and used data on party size and nesting group size to examine seasonal patterns of grouping. Tree fruit availability was positively correlated with rainfall, with a period of relative tree fruit scarcity corresponding with the long dry season. Liana fruit availability was not related to rainfall, and lianas exhibited less variable fruiting patterns across seasons. Fruits made up the majority of the chimpanzee diet, with lianas accounting for 35% of dietary fruit species. Fruits of the liana Saba comorensis were available during all months of phenological monitoring, but they were consumed more when tree fruit was scarce, suggesting that Saba comorensis fruits may be a fallback food for Rubondo chimpanzees. There were no increases in consumption of lower-quality plant parts between seasons, and there were no changes in group size between seasons. These results contrast with evidence from several endemic chimpanzee study sites, and indicate that Rubondo chimpanzees may have access to abundant and high-quality foods year round.

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In this study we report the use of an automated iodometric titration method and a novel gas chromatography (GC) method for the quantitative analysis of dimethyl titanocene (DMT), a key raw material in drug synthesis. Both approaches are based on the reaction of DMT in toluene or tetrahydrofuran solutions with iodine. In the case of iodometric titration, excess iodine is titrated with a standardized aqueous sodium thiosulfate solution to a potentiometric end-point for the determination of DMT concentration. Alternatively, GC is employed to measure the concentration of iodomethane, a product of the reaction between DMT and iodine, in order to determine the concentration of DMT in the solution. Excellent agreement between iodometric titration, GC and NMR results using several DMT samples confirms the accuracy of the two methods and strongly supports the use of either method as a replacement to the expensive NMR for quantitative DMT analysis. The relatively few sources of error associated with the two methods, their ubiquitous nature and ease of application in routine analysis make them the analytical methods of choice, among all. Both methods have been validated according to ICH requirements. The use of iodometric titration method for DMT analysis is demonstrated with a couple of applications.

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This work assessed the changes in both social interactions and estrogen metabolite excreted in feces in eight group-living Japanese macaques (Macaca fuscata). We tested the hypothesis that the social behavior of pregnant females shows significant changes during the late prepartum and early postpartum period. We also tested the hypothesis that the marked fluctuation in estrogen levels during the perinatal period is associated with the changes in social behavior. We found that pregnant females withdrew from the social life of their group in preparation for parturition and only slowly regained their normal social activity after delivery. These changes were correlated with the fluctuation in estrogen conjugate excreted in feces, giving further evidence that hormones can enhance responsiveness to the infant and may predict maternal competence in macaques. We also found that the high frequency of self-grooming by pregnant females during the perinatal period may be a functional way to improve the quality of care toward an infant by a simple shifting from the care for oneself to the care for the infant after parturition.

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Termite mound soils eaten by chimpanzees of the Mahale Mountains and Gombe National Parks, Tanzania, have mineralogical and geochemical compositions similar to many soils eaten by higher primates, but release very low levels of either toxic or nutritional inorganic elements to solution at acid pH. Comparison with control (uneaten) soils from the same areas showed lower levels of carbon and nitrogen in the eaten soils, a relationship confirmed by surface analysis. Surface analysis also revealed lower levels of iron on particle surfaces versus interiors, and higher levels of iron on ingested versus control soil particle surfaces. The soils can adsorb dietary toxins, present in the plant diet or those produced by microorganisms. Taking the toxic alkaloids quinine, atropine, sparteine, and lupanine as examples, it is evident that soils from Mahale have a very good adsorptive capacity. A new adaptive advantage of geophagy is proposed, based on the prevention of iron uptake. The behavior of the soils in vitro is consistent with the theory that geophagy has a therapeutic value for these chimpanzees.

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BACKGROUND: Abdominal aortic aneurysms (AAAs) involve an unfavorable balance between the destruction and the repair of connective tissue proteins. The purpose of this study was to assess the functional importance of connective tissue repair during experimental aneurysmal degeneration. METHODS: Male Wistar rats (n = 70) underwent transient intraluminal perfusion of the abdominal aorta with porcine pancreatic elastase. In Study I, the aortic diameter was measured before elastase perfusion and at days 0, 2, 7, and 14 (n = 6 rats at each interval). Aortic wall concentrations of desmosine (Des) and hydroxyproline (OHP) were measured at each interval, and the expression of tropoelastin (TE), alpha1(I) procollagen (PC), and lysyl oxidase genes was evaluated by reverse transcription-polymerase chain reaction. In Study II, 22 rats were treated with beta-aminopropionitrile (BAPN) to block connective tissue repair. In Study III (n = 30), rats were treated with doxycycline, a matrix metalloproteinase inhibitor, beginning 7 days after elastase perfusion. RESULTS: AAAs consistently developed between 7 and 14 days after elastase perfusion. Aortic wall Des concentration decreased markedly during aneurysm development, reaching 3% of normal by day 14 (377 +/- 22 pmol of Des/sample on day 0 vs 9 +/- 1 pmol of Des/sample on day 14; P <.05). Aortic wall OHP decreased to only 68% of normal at the same interval (121 +/- 10 nmol of OHP/sample on day 0 vs 82 +/- 14 nmol of OHP/sample on day 14; P <.05). TE and PC expression was undetectable in healthy aorta, but they both increased by day 7 (P <.05); while TE expression decreased again by day 14, PC continued to rise. Lysyl oxidase expression progressively decreased at all intervals after elastase perfusion. Treatment with beta-aminoproprionitrile resulted in acute aortic dissection in 81% of the rats (50% mortality). These early deaths occurred between days 3 and 6, coinciding with aortic infiltration by proteinase-secreting inflammatory cells. Delayed treatment with doxycycline suppressed the progression of aneurysmal dilatation between days 7 and 21 (P <.05 vs untreated controls). CONCLUSIONS: The development of elastase-induced AAAs is accompanied by an active process of connective tissue repair. While this reparative process is necessary to stabilize the developing aneurysm wall, it is insufficient to prevent aneurysm progression. In contrast, reducing the proteolytic destruction of connective tissue proteins promotes stabilization of the aneurysmal aorta.

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The ITS-2 sequences for adult specimens of Oesophagostomum stephanostomum from the common chimpanzee and Oesophagostomum bifurcum from the Mona monkey were determined. For both species, the length and GC content of the ITS-2 sequences were 216 bp and 43%, respectively. While there was no unequivocal sequence difference among individual worms representing each of the two species, five (2.3%) interspecific nucleotide differences were detected. These differences were associated with the presence of unique restriction sites in the ITS-2 sequence of 0. stephanostomum for multiple endonucleases of diagnostic value for the differentiation of the two taxa by restriction analysis. Pairwise comparisons of the ITS-2 sequences of O. stephanostomum and O. bifurcum with published ITS-2 sequences for five different congeners indicated that these species from the subgenus Conoweberia are closely related, in accordance with previous morphological studies.

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There is wide interest in the effects of reproductive biology, mating partner preference, and rank on mating success (MS) and reproductive success (RS) in primates. In particular, theory stresses importance on the mechanisms for attaining RS. Most theory hedges on competitive ability and priority of access to resources, whether they be food or estrous females. However, the majority of data used in favor of such hypotheses come from relatively short-term studies. We review these hypotheses based on long-term data from provisioned and unprovisioned populations of Japanese macaques. Neither MS nor RS were consistently attained by high-ranking males and females. For males, female choice and mating partner preference is seen to over-ride most male-male competitive behaviors likely to affect MS and RS through priority of access to estrous females. Long-term mating patterns driven largely by female partner preferences, results in decreasing MS and RS for older higher-ranking males. The long-term trend for females to prefer less familiar or novel partners results in higher MS and RS for younger, middle-ranking males. The effects of this vary according to troop size and the duration of male tenure. For females, no consistent trend was recognized for rank related RS in either provisioned or unprovisioned troops. Non-reproductive mating may provide differential benefit to high-ranking females for access to limited food resources in some habitats but overall the relationship was inconclusive. Distribution and defendability of food resource, rather than provisioning per se may be more important.

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Elastolytic matrix metalloproteinases (MMPs) have been implicated in the pathogenesis of abdominal aortic aneurysms (AAA), a disorder characterized by chronic aortic wall inflammation and destruction of medial elastin. The purpose of this study was to determine if human macrophage elastase (HME; MMP-12) might participate in this disease. By reverse transcription-polymerase chain reaction, HME mRNA was consistently demonstrated in AAA and atherosclerotic occlusive disease (AOD) tissues (six of six), but in only one of six normal aortas. Immunoreactive proteins corresponding to proHME and two products of extracellular processing were present in seven of seven AAA tissue extracts. Total HME recovered from AAA tissue was sevenfold greater than normal aorta (P < 0.001), and the extracted enzyme exhibited activity in vitro. Production of HME was demonstrated in the media of AAA tissues by in situ hybridization and immunohistochemistry, but HME was not detected within the media of normal or AOD specimens. Importantly, immunoreactive HME was specifically localized to residual elastin fragments within the media of AAA tissue, particularly areas adjacent to nondilated normal aorta. In vitro, the fraction of MMP-12 sequestered by insoluble elastin was two- to fivefold greater than other elastases found in AAA tissue. Therefore, HME is prominently expressed by aneurysm-infiltrating macrophages within the degenerating aortic media of AAA, where it is also bound to residual elastic fiber fragments. Because elastin represents a critical component of aortic wall structure and a matrix substrate for metalloelastases, HME may have a direct and singular role in the pathogenesis of aortic aneurysms.

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The need to incorporate research findings into public health nursing has never been greater. This paper describes briefly, the initiatives to promote research in a public health nursing division and the results of the evaluation questionnaire. Results indicated that public health nurses valued research and felt comfortable with the concepts and phases of the research utilization model. They would engage in research activities if conducted at team meetings and when time was allotted. They identified administrative support and the supportive environment as being positive facilitators to research utilization. Despite these findings, the majority (67.5%) were not changing their practice as a result of the initiatives. They identified having difficulty formulating a research question and needing assistance with article critique. Time was cited as the greatest deterrent. They felt they did not have time to read research or engage in the steps of the research utilization model. Recommendations from the evaluation include the need to designate time for research utilization at team meetings. Once the nurses comfort level and value placed on research utilization increases, they may be motivated to initiate research activities on their own.

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OBJECTIVES: In this series of studies, the authors sought to determine some of the cognitive and social boundary conditions that can undermine the accuracy of young children's reporting. Care was taken to include events and interviewing variables that more accurately reflect the experiences of children in real-world investigations of alleged sexual abuse. Videotaped interviews with preschool children were presented to experts to determine how adept they are at distinguishing between true and false accounts. METHOD: All the studies were designed to investigate the susceptibility to suggestion in young preschool children. The difference between studies was the form of that suggestion and the nature of the event to which the children were exposed. All studies measured recall accuracy, false assent rate, and the change in these outcomes over time and/or successive interviews. RESULTS: Very young preschool children (aged 3 and 4 years) were significantly more vulnerable to suggestions than were older preschool children (aged 5 and 6 years). The number of interviews and the length of the interval over which they were presented resulted in the greatest level of suggestibility. CONCLUSIONS: While some types of events (negative, genital, salient) were more difficult to implant in children's statements, some children appeared to internalize the false suggestions and resisted debriefing. These children's false statements were quite convincing to professionals, who were unable to distinguish between true and false accounts.

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With growing concerns over children's suggestibility and how it may impact their reliability as witnesses, there is increasing interest in determining the long-term effects of induced memories. The goal of the present research was to learn whether source misattributions found by Ceci, Huffman, Smith, and Loftus (1994) caused permanent memory alterations in the subjects tested. When 22 children from the original study were reinterviewed 2 years later, they recalled 77% of all true events. However, they only consented to 13% of all false events, compared to the 22% false consent rate (among the same subset of children) found by Ceci et al. (1994). Additionally, while children remained accurate in their recall of true events (they maintained assents 78% of the time), they "recanted" their earlier false consents 77% of the time, after the 2-year delay. Implications of these findings for child witnesses and the legal system are discussed.

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We assessed eyelid function by subjective clinical examination and quantitative means in patients recovering from facial nerve palsy. Electromagnetic search coil techniques were used to record the concurrent movements of the two eyelids to study alterations in blink main sequence (peak velocity versus amplitude) relationships and interocular differences in eyelid kinematics. After onset of unilateral palsy, the paresis of eyelid closure showed varying degrees of recovery. Adaptive increases in blink main sequence slope contributed to maximizing closure of the paretic eyelid. However, blink adaptation mechanisms must operate bilaterally, as there also was evidence of altered main sequence slope in the nonparetic eyelid. In general, main sequence slope was inversely related to the level of eyelid paresis. The highest indices of blink adaptation were in those patients with moderate paresis, and main sequence slope was decreased in those patients with increasing degrees of recovery. The assessment of eyelid function with search coil techniques provides a sensitive means of monitoring disease and treatment course. Data also aid understanding of adaptive gain control in the neural control of blink in health and disease.

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Heart transplantation procedures, which present a number of challenges not generally seen in perioperative nursing practice, provide important knowledge for perioperative nurses because they demonstrate the importance of organization, communication, collaboration, and resourcefulness among surgical team members. On Friday, Aug 13, 1993, the Virginia Heart Center at Fairfax Hospital, Falls Church, implanted donor hearts in three adult recipients in a single day. The day was even more challenging because of elective coronary artery bypass graft procedures performed on three other patients. Successful response to the demands of Aug 13 was facilitated by the presence of skilled, versatile, cardiovascular OR staff members.

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Nurses working in cardiovascular surgery must be responsible and highly competent to meet the demands of their profession. Hospitals that hire nurses for cardiovascular surgery also must assume responsibility for the competency of nurses hired. The Virginia Heart Center at Fairfax Hospital, Falls Church, uses a competency-based orientation plan to train newly hired cardiovascular surgery nurses in providing quality care. Competency-based orientation is an effective approach to incorporating new members of the team into the work environment. The benefits of this appraoch include the development of teamwork and esprit de corps, skill and knowledge enhancement, and possible increased staff retention.

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Bitter principles and related constituents have been isolated from Vernonia amygdalina (Compositae), a plant ingested by wild chimpanzees sometimes suffering from parasite-related diseases in the Mahale Mountains National Park, Tanzania. These isolated constituents were the known sesquiterpene lactones (vernodalin, vernolide, hydroxyvernolide), and new stigmastane-type steroid glucosides (vernonioside A1-A4: for bitter tasting constituents and vernonioside B1-B3; for nonbitter related constituents). Antiparasitic activity tests of these constituents together with quantitative analyses of the major active constituents, vernodalin and vernonioside B1, supported the hypothesis that Mahale chimpanzees control parasite-related diseases by ingesting the pith of this plant, found to contain several steroid-related constituents. While the major active steroid-related constituents (vernonioside B1 and its primary aglycone, vernoniol B1) do not taste bitter themselves, it was hypothesized that the highly bitter constituents including vernodalin may play an important role as signals to the ingester guiding their choice of the appropriate plant, plant part, and possibly also as signals which help to control the amount of intake.

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