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G.A.T.S. and universities: implications for research.

The likely impact of applying the General Agreement on Trade in Services (GATS) to higher education are examined. GATS aims to "open up" services to competition: no preference can be shown to national or government providers. The consequences for teaching are likely to be that private companies, with degree-awarding powers, would be eligible for the same subsidies as public providers. Appealing to the inadequate recently introduced "benchmark" statements as proof of quality, they would provide a "bare bones" service at lower cost. Public subsidies would go: education being reduced to that minimum which could be packaged in terms of verifiable "learning outcomes". The loss of "higher" aspirations, such education of critically-minded citizens of a democratic and civilized society would impoverish the university's research culture which demands honesty and openness to public scrutiny. Most university research is substantially supported by public subsidy. Under GATS discipline, commercial providers of research services could be entitled to similar public subsidies. Publicly funded fundamental research would fade, leaving university research totally dependent for funds upon the good will of industry and commerce. Present problems, such as the suppression of unwelcome results and the use of questionable results to manipulate public opinion, would considerably increase. The public would lose a prime source of trustworthy knowledge, needed in political discourse, legal disputation, consumer protection and in many other contexts.

Capitalism↗

Monitoring the source of memory in detoxified alcoholics.

The ability to monitor the source of remembered information and related reflective cognitive processes was examined in normal volunteers and detoxified alcoholics. Normal volunteers were very accurate judges of whether remembered events were presented as stimuli or were self-generated, even when memory was tested 2 days later. In contrast, a subgroup of otherwise cognitively unimpaired alcoholics demonstrated impairments in the ability to track the source of remembered knowledge and were also less able to inhibit intrusion errors in recalling information from memory. These findings provide preliminary evidence of an impairment in cognitive control functions in certain alcoholics. This conclusion is supported by associated findings indicating that, among alcoholics, performance on explicit memory tasks that required reflective cognitive operations were positively correlated with glucose utilization rates in left prefrontal, temporal, and posterior orbital frontal cortical regions.

Adult↗

Development of sex differences in the response of spiny mouse pups to adult male odors.

Using a three-choice preference test, olfactory-mediated investigatory activity in response to adult male urine odor was examined in a precocially active rodent, the spiny mouse (Acomys cahirinus) aged between 3-26 days. Temporally related sex differences were seen in the time spent in the presence of the odors of father's or unfamiliar adult male's urine, or distilled (control) water. Neither male nor female pups discriminated between odors from the father and strange adult males. After the first olfactory test, when the pups were aged between four and six days, male pups strongly preferred to stay in the vicinity of urine odors of adult males, whereas female pups avoided odors of adult males and remained in the enclosure with the control odor source. To our knowledge this is the first time that such a behavioral sex difference related to olfaction has been shown to occur in young rodent pups. We suggest that the sexually dimorphic response of the pups is associated with the development of later sex differences in behavior.

Animals↗

Cobalamin and folate metabolism in helminths.

Knowledge about the source, metabolism and functions of cobalamins and folates in helminths remains fragmentary. It is likely that all helminths, whether free-living or parasitic, cannot synthesize cobalamins and folates de novo. Folates, but not cobalamins, appear to be ubiquitous in helminths. Of the parasitic helminths that take up free cobalamins in vitro, all but one species showed no uptake of cobalamin bound to transport proteins, although the latter type of cobalamin by far predominates in vivo. Certain free-living and parasitic helminths in vitro and in vivo took up a variety of folyl and antifolyl monoglutamates, but it is not known whether helminths can take up any folyl polyglutamates. Helminths that have any folate-dependent metabolism appear able to produce polyglutamylated forms of the required tetrahydrofolate coenzymes. Helminths that possess a functional cobalamin-dependent pathway from succinyl CoA to propionyl CoA appear able to form the required adenosylcobalamin coenzyme. Only free-living helminths may possess a cobalamin (and 5-methyltetrahydrofolate)-dependent pathway from homocysteine to methionine. It is likely that all helminths possess the 5,10-methylenetetrahydrofolate-dependent pathway from deoxyuridylate to thymidylate. All helminths appear able to salvage purine bases and nucleosides, but 10-formyltetrahydrofolate-dependent de novo purine ribonucleotide synthesis has been demonstrated unequivocally only in nematodes. The primitive parasitic groups of helminths exhibit cobalamin metabolism, whereas the more highly evolved ones seem to have lost the mechanisms for uptake and the associated biochemical pathways utilizing cobalamins.

Animals↗

Crystallization of AcpA, a respiratory burst-inhibiting acid phosphatase from Francisella tularensis.

Francisella tularensis is a highly infectious bacterial pathogen that is classified as a Category A Pathogen by the Centers for Disease Control and Prevention. Here, we report crystallization of a recombinant form of F. tularensis AcpA, a unique and highly expressed acid phosphatase that is thought to play a role in intracellular survival by inhibiting the host respiratory burst. Three crystal forms have been obtained, with form III being the most suitable for high-resolution structure determination. Form III crystals were grown in the presence of PEG 1500 and the competitive inhibitor sodium orthovanadate (5 mM). The space group is C222(1) with unit cell parameters a=112.1 A, b=144.4 A, c=123.9 A. The asymmetric unit is predicted to contain two protein molecules and 43% solvent. A 1.75-A native data set was recorded at beamline 8.3.1 of the Advanced Light Source. To our knowledge, this is the first report of high-resolution crystals of any F. tularensis protein.

Acid Phosphatase↗

Modelling the spatial distribution of ammonia emissions from seabirds in the UK.

Knowledge of the sources and distribution of ammonia (NH3) emissions underpins our understanding of the nitrogen budget. Research has focused on quantifying NH3 emissions from anthropogenic sources, whilst those from natural sources have received little attention internationally. Seabirds excrete large quantities of nitrogen, making seabird colonies a major natural source of NH3. Ammonia emissions from each UK seabird species were estimated and combined with population distribution data to model their spatial distribution. Total NH3 emissions from UK seabirds were estimated at 2.7 kt per year. Seabird emissions are concentrated in remote parts of the UK where anthropogenic emissions are small, so that seabirds often represent the main source of NH3 emissions in these areas. Seabird NH3 emissions were found to have increased by 34% since the 1970s. This corresponds to population changes which may be influenced by human activities, showing that even this natural source can be anthropogenically modified.

Agriculture↗

A taxonomic description of computer-based clinical decision support systems.

OBJECTIVE: Computer-based clinical decision support systems (CDSSs) vary greatly in design and function. Using a taxonomy that we had previously developed, we describe the characteristics of CDSSs reported in the literature. METHODS: We searched PubMed and the Cochrane Library for randomized controlled trials (RCTs) published in English between 1998 and 2003 that evaluated CDSSs. We coded each CDSS using our taxonomy. RESULTS: 58 studies met our inclusion criteria. The 74 reported CDSSs varied greatly in context of use, knowledge and data sources, nature of decision support offered, information delivery, and workflow impact. Two distinct subsets of CDSSs were seen: patient-directed systems that provided decision support for preventive care or health-related behaviors via mail or phone (38% of systems), and inpatient systems targeting clinicians with online decision support and direct online execution of the recommendations (18%). 84% of the CDSSs required extra staffing for handling CDSS-related input or output. CONCLUSION: Reported CDSSs are heterogeneous along many dimensions. Caution should be taken in generalizing the results of CDSS RCTs to different clinical or workflow settings.

Databases, Bibliographic↗

Complementary activity of an ancient combination of natural ingredients on the dysbiosis symptoms linked to acne.

ETHNOPHARMACOLOGICAL RELEVANCE: Acne is one of the most common dermatologic diseases in the world. It is due to the secretion of a high level of sebum that causes follicular hyperkeratinisation, alterations of the cutaneous microbiota, and inflammatory processes. One of the first-line treatments is still an antibiotic prescription, that inhibits bacterial growth and, as a consequence, lowers some of the other symptoms. Nevertheless, this high level of antibiotic prescription contributes to the increase of antibiotic resistance. Alternatives to antibiotics are thus highly required, as acne does not represent per se an infection. AIM OF THE STUDY: In the frame of the IRGAP (Interdisciplinary Research Group on Ancient Pharmacopeias) consortium, different preparations dedicated to cutaneous ailments have been identified based on ancient traditional uses, dating back to Antiquity or Middle Ages. Among them, the combination of Aloe vera and Myrrh was widely conserved over centuries. Even though this combination is no longer in use, we wondered why this combination was so widely conserved. We considered the use of this combination of ingredients to treat acne, a case study for which both plants are still used, but separately. MATERIALS AND METHODS: The effects of both plant extracts were analyzed on the growth of different bacteria from the skin microbiota, cultivated alone or in co-culture conditions. As the skin is a rather heterologous environment, we further tested the robustness of our study by varying the experimental conditions. We further analyzed any complementary effects of these extracts on the inflammation process linked to acne. RESULTS: We showed that both plant extracts have complementary effects on micro-organisms and on macrophages. Indeed, while Myrrh extracts inhibited the growth of specific skin microbiota bacteria, Aloe vera gel extracts on the opposite, favored the growth of others: the two plants could act in a complementary way to restore a healthy microbiota. Another complementarity was also observed on macrophages: while Myrrh extracts showed an anti-inflammatory effect, Aloe vera gel extracts showed an antioxidant effect. CONCLUSION: Our results highlight the potential of the combination of Myrrh and Aloe vera to address both the dysbiosis of the skin microbiota and the inflammation associated with acne. Thus, this exploration of forgotten combinations from historical pharmacopoeias underscores the importance of revisiting past traditional knowledge as a source of innovation.

Aloe vera↗

Stereoselective effects of 3-hydroxybutyrate on glucose utilization of rat cardiomyocytes.

In researches of ketone bodies, D-3-hydroxybutyrate (D-3HB) is usually the major one which has been investigated; in contrast, little attention has been paid to L-3-hydroxybutyrate (L-3HB), because of its presence in trace amounts, its dubious metabolism, and a lack of knowledge about its sources. In the present study we determined the distributions of enantiomers of 3-hydroxybutyrate (3HB) in rat brain, liver, heart, and kidney homogenates, and we found the heart homogenate contained an enriched amount of L-3HB (37.67 microM/mg protein) which generated a significant ratio of 66/34 (D/L). The ratio was altered to be 87/13 in the diabetic rat heart homogenate. We subsequently found this changed ratio of D/L-3HB may contribute to reduce glucose utilization in cardiomyocytes. Glucose utilization by cardiomyocytes with 5 mM of D-3HB was decreased to 61% of the control, but no interference was observed when D-3HB was replaced with L-3HB, suggesting L-3HB is not utilized for the energy fuel as other ketone bodies are. In addition, the reduced glucose utilization caused by D-3HB gradually recovered in a dose-dependent manner with administration of additional L-3HB. The results gave the necessity of taking L-3HB together with D-3HB into account with regard to glucose utilization, and L-3HB may be a helpful substrate for improving inhibited cardiac pyruvate oxidation caused by hyperketonemia.

3-Hydroxybutyric Acid↗

A deformable digital brain atlas system according to Talairach and Tournoux.

Brain atlases are valuable tools which assist neurosurgeons during the planning of an intervention. Since a printed atlas book has several disadvantages-among them the difficulty to map the information onto a patient's individual anatomy-we have developed a digital version of the well-established stereotaxic brain atlas of Talairach and Tournoux. Our atlas system is mainly dedicated to assist neurosurgical planning, and its benefits are: (i) a three-dimensional (3D) representation of most brain structures contained in the Talairach atlas; (ii) a nonrigid matching capability which warps the standard atlas anatomy to an individual brain magnetic resonance imaging (MRI) dataset in a few minutes and which is able to take deformations due to tumors into account; (iii) the integration of several sources of neuroanatomical knowledge; (iv) an interface to a navigation system which allows utilization of atlas information intraoperatively. In this paper we outline the algorithm we have developed to achieve 3D surface models of the brain structures. Moreover, we describe the nonrigid matching method which consists of two tasks: firstly, point correspondences between the atlas and the patient are established in an automatic fashion, and secondly these displacement vectors are interpolated using a radial basis function approach to form a continuous transformation function. To generate appropriate target structures for the first of these tasks, we implemented a quick segmentation tool which is capable to segment the cortex and ventricles in less than 5 min. An evaluation shows that our nonrigid approach is more precise than the conventional piecewise linear matching, though it should be further improved for the region around the deep grey nuclei. Summarizing, we developed a Win32 program which permits the convenient and fast application of standardized anatomy to individual brains which potentially contain tumors.

Algorithms↗

Automated segmentation of the left ventricle in cardiac MRI.

We present a fully automated deformable model technique for myocardium segmentation in 3D MRI. Loss of signal due to blood flow, partial volume effects and significant variation of surface grey value appearance make this a difficult problem. We integrate various sources of prior knowledge learned from annotated image data into a deformable model. Inter-individual shape variation is represented by a statistical point distribution model, and the spatial relationship of the epi- and endocardium is modeled by adapting two coupled triangular surface meshes. To robustly accommodate variation of grey value appearance around the myocardiac surface, a prior parametric spatially varying feature model is established by classification of grey value surface profiles. Quantitative validation of 121 3D MRI datasets in end-diastolic (end-systolic) phase demonstrates accuracy and robustness, with 2.45 mm (2.84 mm) mean deviation from manual segmentation.

Algorithms↗

Dissolved and particulate nutrient export from rural catchments: a case study from Luxembourg.

Nutrient enrichment of freshwaters continues to be one of the most serious problems facing the management of surface waters. Effective remediation/conservation measures require accurate qualitative and quantitative knowledge of nutrient sources, transport mechanisms, transformations and annual dynamics of different nitrogen (N) and phosphorus (P) forms. In this paper, nitrate (NO3-N), soluble reactive phosphorus (SRP) and total phosphorus (TP) concentrations and loads are presented for two adjacent rural basins of 306 km2 and 424 km2, and for five sub-basins differing in size (between 1 km2 and 33 km2), land use (extent of forest cover between 20% and 93%) and household pressure (from 0 to 40 people/km2) with the aim of studying the influence of land use and catchment size on nutrient exports. The studied catchments are all situated on Devonian schistous substrates in the Ardennes region (Belgium-Luxembourg), and therefore have similar hydrological regimes. As the study period could not be the same for all basins, annual export coefficients were corrected with the 25 years normalized discharge of the Sure River: two regression analyses (for dry and humid periods) relating monthly nutrient loads to monthly runoff were used to determine correction factors to be applied to each parameter and each basin. This procedure allows for the comparing annual export coefficients from basins sampled in different years. Results show a marked seasonal response and a large variability of NO3-N export loads between forested (4 kg N ha-1 year-1), agricultural (27-33 kg N ha-1 year-1) and mixed catchments (17-22 kg N ha-1 year-1). For SRP and TP, no significant agricultural impact was found. Land and bank erosion control the total P massflow in the studied catchments (0.4-1.3 kg P ha-1 year-1), which is mostly in a particulate form, detached and transported during storm events. Soluble reactive P fluxes ranged between 10% and 30% of the TP mass, depending on the importance of point sources in the basins studied. No relation was found between the size of the basins and the export of nitrate, SRP or TP. Nutrient export, specially for NO3-N and TP, shows significant inter-annual variations, closely linked to inter-annual discharge variations. Flow and load frequency data analysis confirm this association for all the basins on an annual basis. Seasonal or storm specific fluxes strongly deviate from their annual values.

Environmental Monitoring↗

Efficacy of an educational program on dialysis, renal transplantation, and organ donation on the opinions of high school students: a randomized controlled trial.

AIM: Organ shortage is a rate-limiting factor for transplantation. The aim of this study was to evaluate the impact of an educational program targeted to high school students on opinions concerning organ donation. METHODS: Sixteen public high schools in Torino, Italy, were randomized (2001 to 2002) as interventions (n = 8) or controls (n = 8). Intervention was composed of first questionnaire, first lesson (one to two classes; 2 hours, by a trained nephrology fellow); second lesson (all classes together; coordinated by a nephrologist, with patients and trainees); second questionnaire. Control included questionnaires. Statistical analysis compared the opinions in the questionnaires after stratification for age, sex, and type of school. RESULTS: Fourteen schools completed the program (seven interventions: 937 first and 808 second questionnaires; controls: 739 and 659). Television (82.5%) and newspapers (43.2%) were the main sources of information; knowledge on renal transplantation (grafts feasible per patient, average duration) was low; only 12.2% of the students gave correct answers. The opinions on living donation were highly positive (76.8%) with no difference in control, intervention schools, first and second questionnaires, according to sex, age, or type of school. The opinions on cadaveric transplantation were affected by the educational intervention with a drop in negative answers (from 33.7% to 16%), with an increase in positive (from 31.5% to 42.9%) and in uncertain ones (from 34.8% to 41.1%) among the intervention schools; 98% of the students appreciated the program. CONCLUSION: The positive effect on student opinions suggests the need to develop educational approaches as a part of our routine clinical work.

Adolescent↗

Towards a more plant physiological perspective on soil ecology.

Soil respiration almost balances carbon fixation by terrestrial photosynthesis and exceeds all anthropogenic carbon emissions by an order of magnitude, yet we lack precise knowledge of the sources of, and controls upon, the release of carbon dioxide from soils. Here, we discuss the increasing evidence that half of this carbon release is from living plant roots, their mycorrhizal fungi and other root-associated microbes, and that this release is driven directly by recent photosynthesis. The new studies challenge the widespread view that soil activity is dominated by decomposer organisms using older detrital material and that root litter inputs equal those of aboveground litter. The new observations emphasize the physiological continuity and dynamic interdependence of the plant-microbe-soil system and highlight the need for closer cooperation between plant and soil scientists.

Carbon↗

Perioperative care of patients with latex allergy.

Initially identified in the pediatric population, latex allergy and sensitivity now are seen at increasingly higher rates in all age groups, and are especially prevalent in health care workers. Knowledge about the sources of latex in the environment, the signs and symptoms seen in latex sensitivity and allergic reaction, risk factors for sensitivity, and how to assess patients and those working in the health care profession for possible latex sensitivity is important for perioperative nurses.

Dermatitis, Contact↗

Legal, ethical, and professional issues to consider when communicating via the Internet: a suggested response model and policy.

Providing nutrition information via the Internet enables dietetics professionals to expand their practices, markets, and networks, but also presents new legal, ethical, and professional issues. Based on her experiences responding to unsolicited questions through a Spanish-language nutrition Web site, this author presents issues related to electronic communication, a process for formulating responses, and makes suggestions for a policy. The issues include the global nature of cyberspace; cultural variations in Spanish-language food terms and models, credentialing, licensure, and scope of practice; presentation of credentials; the inquirer's knowledge and information sources; the nature of the cyberspace relationship; and protection of the client and the professional. These issues have created a need for an electronic communication policy and some components of such a policy are identified, including the nature of electronic nutrition, distinguishing between public and client-specific communication, question-and-answer formats, opening and closing caveats, and recording processes.

Computer Simulation↗

Plants as source of drugs.

This work presents a study of the importance of natural products, especially those derived from higher plants, in terms of drug development. It describes the main strategies for obtaining drugs from natural sources, fields of knowledge involved, difficulties and perspectives. It also includes a brief discussion of the specific situation in Brazil regarding the use of, trade in, and research into therapeutic resources of natural origin and the general lack of awareness of the use of potentially toxic plants, mainly in folk medicine.

Brazil↗

Perspectives on prostate cancer treatment: awareness, attitudes, and relationships.

OBJECTIVES: To compare prostate cancer patients' perceptions with those of physicians regarding treatments, awareness, attitudes, and views of the relationships between the two groups. METHODS: One thousand randomly selected members of US TOO International, Inc., and 200 doctors actively involved in the treatment of prostate cancer, were involved in the study. RESULTS: Almost half of the prostate cancer patients surveyed (48%) were diagnosed with the disease between the ages of 60 and 69; almost one-third were over the age of 70 (31%), and one-fifth (21%) younger than 60 years old. Doctors feel more confident than patients that the patients were sufficiently informed to make treatment decisions, although the majority of patients surveyed reported they took a very active or somewhat active role in the treatment decision process. The doctors' recollection of discussing treatment options exceeded the patients' recollections of those discussions. Doctors and patients alike believe support groups, such as US TOO, to be supportive. CONCLUSIONS: Although recollections of treatment discussions differ between doctors and patients, ongoing communication is very important. The majority of patients state they have relied upon several sources for gaining knowledge of their disease and their options, namely, their doctors, other health professionals, and support groups.

Attitude↗