Plant volatiles: new perspectives for research in Brazil

Agroecosystems consist on complex trophic relationships among host plants, herbivores and their natural enemies. This article reviews the research of plant volatiles in Brazil, in order to determine multiple resistance mechanisms of economically important crops and to contribute to the understanding of insect-plant interactions. Most pest management programs, including chemical and biological control, do not consider the impact of these chemicals on herbivores and their natural enemies. Alternative control methods are being developed in order to improve our understanding on the endogenous mechanisms of plant induced defenses against phytophagous arthropods. The use of plant volatiles technology as an additional tool in integrated pest management programs would offer a new and environmentally sound approach to crop protection. This technique involves the development of baits that attract beneficial organisms and the manipulation of biochemical processes that induce and regulate plant defenses, key factors in the improvement of control programs against economically important pests. The elucidation of the mechanisms involved in the indirect defenses of plants will result in useful tools for biological control of crop pests.     

Detecting possible persons of interest in a physical activity program using step entries: Including a web-based application for outlier detection and decision-making

According to recent statistics from the World Health Organization, 23% of people aged 18 years and over are not sufficiently physically active. Strangely, this is at a time when, due to the improvement in sensor technology, physical activity programs that track physical activity have become popular. However, some participants who enroll in these programs cheat by manipulating the data they enter. This can be discouraging for other participants, also invalidating the overall accuracy of program outcomes. Therefore, detecting these participants and discarding their manipulated entries is important in order to maintain the quality of the program. Currently, most of these physical activity programs use manual processes to detect and reject fraudulent step entries by reviewing the participant's demographic profiles along with their longitudinal step count performance data. In this study, a process, including two parallel models for detecting person of interest characteristics and abnormal step count entries, is developed. The first model uses the penalized logistic regression with Synthetic Minority Over-sampling Technique subsampling to address the imbalance in the proportion of genuine and persons of interest. Having a highly imbalanced distribution between genuine and person of interest profiles makes this task more challenging. The second model uses a variety of outlier detection methods to detect and reject abnormal step entries based on previously entered data. This process will be more efficient and productive compared to the current manual system and will support better decision-making in the future. The proposed system can be applied for other fraud detection applications after suitable adjustments.     

Overview and relevance of Wolbachia bacteria in biocontrol research

Wolbachia bacteria are an unsuspected, but potentially important, component of many biocontrol programs. To heighten awareness of these bacteria, we review current knowledge of Wolbachia and their possible application in biocontrol research. Wolbachia promote their spread by altering the reproductive success of their arthropod hosts. This ability frequently is identified as having potential either to reduce populations of pest species, or to increase populations of beneficial species. However, only 19 and 1% of peer-reviewed research articles (n=844) on Wolbachia appear in arthropod- and biocontrol-specific journals, respectively. Although Wolbachia will not have application for all programs, their prevalence cannot be denied. We screened for Wolbachia in populations of arthropods of current interest to biocontrol programs in Canada. Infections were detected in 47% of 177 populations, representing 46% of the 105 species tested. Greater awareness, in combination with the rapidly expanding knowledge base of Wolbachia and similar endosymbionts, offers new directions for research in biocontrol programs. We recommend that all arthropod species in biocontrol programs be screened for these bacteria.     

Lessons from the clinical trials of interleukin-2

The initial results of interleukin-2 (IL-2) therapy in man are reviewed from the perspective of how they conform to predictions from preclinical studies. These preclinical models predict that tumors will vary in their susceptibility to IL-2 therapy and will be most successfully treated at lower tumor burdens. In addition, the dose and schedule of IL-2 are important for successful therapy. Host-related factors, including the presence of suppressor activities, may also be important. In these models, the addition of other cytokines, including interferon-alpha or tumor necrosis factor, to IL-2 can enhance antitumor activity. The concomitant administration of ex vivo IL-2-activated lymphokine-activated killer cells or tumor-infiltrating lymphocytes also enhances the IL-2 antitumor effect. Clinical trials addressing all of these issues have been completed or are underway; the results suggest overall that the preclinical models are predictive, with both host- and tumor-related factors as well as such IL-2-therapy-related factors as dose, schedule, route and the use of additional agents all playing a role in the success of therapy. A more complete understanding of the mechanisms of response and resistance involved in this therapy will facilitate the rational development of more effective and less toxic IL-2-based therapy of human malignancy.     

Control of onchocerciasis today: status and challenges

The filarid parasite Onchocerca volvulus is the causative agent of human onchocerciasis (river blindness), an infection characterized by chronic skin and eye lesions. There are three regional programs currently dedicated to controlling onchocerciasis in the endemic areas of Africa and the Americas: the Onchocerciasis Control Programme of West Africa, the African Programme for Onchocerciasis Control and the Onchocerciasis Elimination Program for the Americas. All three programs use periodic mass treatment with the microfilaricidal drug ivermectin with differing strategic purposes and, as a result, face different challenges to reach their goals. This paper will review the strategies, status and challenges of these three programs.     

Differences in the cytochrome P-450 isoenzymes involved in the 2-hydroxylation of oestradiol and 17 alpha-ethinyloestradiol. Relative activities of rat and human liver enzymes.

The metabolism of oestradiol and 17 alpha-ethinyloestradiol to their 2-hydroxy derivatives is an important determinant in their biological effects. In this work, we have investigated which rat or human cytochrome P-450 isoenzymes are involved in catalysing these reactions. Oestradiol 2-hydroxylation was catalysed by a wide variety of rat cytochrome P-450s from gene families P450IA, P450IIB, P450IIC and P450IIIA. Interestingly, 17 alpha-ethinyloestradiol, which only differs structurally from oestradiol at a position distant from the site of oxidation, was metabolized predominantly by members of the P450IIC gene subfamily. In order to establish which enzymes are responsible for the oxidation of these substrates in man, antibodies to rat liver cytochrome P-450 isoenzymes were used to inhibit these reactions in a panel of human liver microsomal fractions. Also, possible correlations between the proteins recognized by the antibodies and the 2-hydroxylation rate were determined. These experiments provide evidence that 2-hydroxylation of 17 alpha-ethinyloestradiol in man is catalysed by cytochromes from the P450IIC, P450IIE and P450IIIA gene families. In contrast, the major proteins involved in oestradiol metabolism are from the P450IA gene family, although members of the P450IIC and P450IIE gene families may also play a role. These data demonstrate that the differences in the capacity of rat P-450s to metabolize these substrates are also present in the comparable enzymes involved in man, and that a variety of factors will determine the rate of disposition of these compounds in man.     

Import of palaeoethnobotanical facts

By the year 2000, palaeoethnobotany will have been functional as an integral part of archaeology for somewhat less than 100 yr. Initially admired for the longevity of their persistence, archaeological plant remains gradually came to be an indication of the diet of prehistoric people. In some species, the archaeological plant remains also indicate the developmental history of the cultivated plant. For others, no wild ancestor is known or revealed by the archaeological plant remains. As greater knowledge is assembled of the plants useful for man, patterns of prehistoric distribution are revealed. The more exact location of the area of origin of cultivated species will become increasingly important to a population faced with chronic food shortages as this will guide botanists to ancestral species and their close relatives. From this reservoir will come desirable plant attributes that can be bred into high-yielding, but genetically depauperate strains of crop plants. The predicted scarcity of petroleum about the year 2000 will lead to high cost or lack of petrochemicals whose use may be substituted for by disease and insect-resistant strains found in the area of a crop’s origin. That area may also offer biological controls, which will offset the lack of insecticides and fungicides. Although it is unlikely that early man overlooked useful plants that might be brought into cultivation, areas of diversity of crop plants are also prime areas to be investigated for new crop plants.     

Strategies for avoiding reinventing the precollege education and outreach wheel

The National Science Foundation's recent mandate that all Principal Investigators address the broader impacts of their research has prompted an unprecedented number of scientists to seek opportunities to participate in precollege education and outreach. To help interested geneticists avoid duplicating efforts and make use of existing resources, we examined several precollege genetics, genomics, and biotechnology education efforts and noted the elements that contributed to their success, indicated by program expansion, participant satisfaction, or participant learning. Identifying a specific audience and their needs and resources, involving K-12 teachers in program development, and evaluating program efforts are integral to program success. We highlighted a few innovative programs to illustrate these findings. Challenges that may compromise further development and dissemination of these programs include absence of reward systems for participation in outreach as well as lack of training for scientists doing outreach. Several programs and institutions are tackling these issues in ways that will help sustain outreach efforts while allowing them to be modified to meet the changing needs of their participants, including scientists, teachers, and students. Most importantly, resources and personnel are available to facilitate greater and deeper involvement of scientists in precollege and public education.     

Why do teens smoke? American Indian and Hispanic adolescents' perspectives on functional values and addiction

Tobacco use by the young is one of the greatest public health concerns in the United States and is targeted by a number of prevention and control programs. A fuller understanding of the social and cultural values that youths attach to smoking is important in achieving focused, effective prevention strategies. Drawing on data collected through individual and focus group interviews, this article examines reasons that Hispanic and American Indian youths give to explain their smoking. The analysis presented here focuses on two interrelated sets of reasons: the functional values of tobacco use (including mood management, peer influences, and image maintenance) and addiction. This article concludes with a discussion of the implications these data may have for prevention and cessation programs aimed at youth and outlines ideas for an anthropological research agenda on youth and tobacco.     

Integration of post-graduate studies with corporately funded biotechnology programs

Post graduate research students need to undertake programs that will develop their potential as a scientist. They need to acquire skills to develop scientific argument, design an experimental approach to test a hypothesis, obtain and analyse data, and effectively communicate their ideas and findings to the scientific community. Many biotechnology-based programs are now funded by industry partnerships and integrating post graduate students into these programs require special considerations.     

Modeling herbivore functional responses causing boom‐bust dynamics following predator removal

Native biodiversity is threatened by invasive species in many terrestrial and marine systems, and conservation managers have demonstrated successes by responding with eradication or control programs. Although invasive species are often the direct cause of threat to native species, ecosystems can react in unexpected ways to their removal or reduction. Here, we use theoretical models to predict boom‐bust dynamics, where the removal of predatory or competitive pressure from a native herbivore results in oscillatory population dynamics (boom‐bust), which can endanger the native species’ population in the short term. We simulate control activities, applied to multiple theoretical three‐species Lotka‐Volterra ecosystem models consisting of vegetation, a native herbivore, and an invasive predator. Based on these communities, we then develop a predictive tool that—based on relative parameter values—predicts whether control efforts directed at the invasive predator will lead to herbivore release followed by a crash. Further, by investigating the different functional responses, we show that model structure, as well as model parameters, are important determinants of conservation outcomes. Finally, control strategies that can mitigate these negative consequences are identified. Managers working in similar data‐poor ecosystems can use the predictive tool to assess the probability that their system will exhibit boom‐bust dynamics, without knowing exact community parameter values.     

Research at the European Synchrotron Radiation Facility medical beamline.

The application of synchrotron radiation in medical research has become a mature field of research at synchrotron facilities worldwide. In the relatively short time that synchrotrons have been available to the scientific community, their characteristic beams of UV and X-ray radiation have been applied to virtually all areas of medical science which use ionizing radiation. The ability to tune intense monochromatic beams over wide energy ranges differentiates these sources from standard clinical and research tools. At the European Synchrotron Radiation Facility (Grenoble, France), a major research facility is operational on an advanced wiggler radiation beamport, ID17. The beamport is designed to carry out a broad range of research ranging from cell radiation biology to in vivo human studies. Medical imaging programs at ID17 include transvenous coronary angiography, computed tomography, mammography and bronchography. In addition, a major research program on microbeam radiation therapy is progressing. This paper will present a very brief overview of the beamline and the imaging and therapy programs.     

Bone marrow suppression and severe anaemia associated with persistent Plasmodium falciparum infection in African children with microscopically undetectable parasitaemia

In sub-Saharan Africa the highest overlap between malaria and HIV infections occurs in female adolescents. Yet control activities for these infections are directed to different target groups, using disparate channels. This reflects the lack of priority given to adolescents and the absence of an accepted framework for delivering health and health-related interventions to this high-risk group. In this paper it is argued that female adolescents require a continuum of care for malaria and HIV – prior to conception, during and after pregnancy and that this should be provided through adolescent services. The evidence for this conclusion is presented. A number of African countries are commencing to formulate and implement adolescent-friendly policies and services and disease control programs for malaria and HIV will need to locate their interventions within such programs to ensure widespread coverage of this important target group. Failure to prioritize adolescent health in this way will seriously limit the success of disease control programs for malaria and HIV prevention.     

School Health-History Forms—A Study of Those Used in California,with Suggestions for Changes

The health history form has an important role in the evaluation of student performance. Recommendations for therapeutic programs may be based on information gained from the health history.One hundred three California high schools reported the frequency of their use of the health history form. Only 56 percent of these schools require health histories of their new students. Only 38 percent obtain health histories from their athletes.Sixty-four of the 103 California high schools responding enclosed copies of the health history form in use in their schools. Analysis of these forms revealed a lack of uniformity of content and, in general, failure to obtain information pertinent to the in-school student problem.A format for a school health history form whose primary purpose is to reveal school-related health data was developed.     

Approaches to antiretroviral therapy in China

INTRODUCTION Advances in antiretroviral therapy (ART) have resulted in dramatic declines in hospitalizations and death rates in the U.S. and Europe, with concomitant steady increases in life expectancy. In China, the government has recog- nized the imminent threat that HIV/AIDS poses to its popu- lation and responded with a national antiretroviral (ARV) treatment program providing ARV drugs free to those most in need [1]. However, given the potentially catastrophic impact of HIV …     

The teaching of protein synthesis - a microcomputer based method

Two programs written in BASIC are used for the teaching of protein synthesis. Students may individually and at their own pace test their knowledge of base pairing using one of the programs. Again individually, students then investigate the process of protein synthesis using randomly generated DNA sequences produced by the second program. Students are thereby reinforcing their understanding of base pairing, complementary sequences, triplet codons, and relating nucleotide sequences to amino acid sequences. The final part of the second exercise introduces a known genetic defect of man.