bluuebunny/crossref_metadata_2025_split huggingface dataset:
Teaching and assessing medical ethics: where are we now?
Authors: Mattick K , Bligh J 
Published: February 2006

Objectives:To characterise UK undergraduate medical ethics curricula and to identify opportunities and threats to teaching and learning.Design:Postal questionnaire survey of UK medical schools enquiring about teaching and assessment, including future perspectives.Participants:The lead for teaching and learning at each medical school was invited to complete a questionnaire.Results:Completed responses were received from 22/28 schools (79%). Seventeen respondents deemed their aims for ethics teaching to be successful. Twenty felt ethics should be learnt throughout the course and 13 said ethics teaching and learning should be fully integrated horizontally. Twenty felt variety in assessment was important and three tools was the preferred number. A shortfall in ethics core competencies did not preclude graduation in 15 schools. The most successful aspects of courses were perceived to be their integrated nature and the small group teaching; weaknesses were described as a need for still greater integration and the heavily theoretical aspects of ethics. The major concerns about how ethics would be taught in the future related to staffing and staff development.Conclusions:This study describes how ethics was taught and assessed in 2004. The findings show that, although ethics now has an accepted place in the curriculum, more can be done to ensure that the recommended content is taught and assessed optimally.
Microarray Analysis of Bleomycin-Exposed Lymphoblastoid Cells for Identifying Cancer Susceptibility Genes
Authors: Cloos Jacqueline , de Boer Wim P.H. , Snel Mireille H.J. , van den IJssel Paul , Ylstra Bauke , Leemans C. René , Brakenhoff Ruud H. , Braakhuis Boudewijn J.M. 
Published: March 2006

Abstract
The uncovering of genes involved in susceptibility to the sporadic cancer types is a great challenge. It is well established that the way in which an individual deals with DNA damage is related to the chance to develop cancer. Mutagen sensitivity is a phenotype that reflects an individual's susceptibility to the major sporadic cancer types, including colon, lung, and head and neck cancer. A standard test for mutagen sensitivity is measuring the number of chromatid breaks in lymphocytes after exposure to bleomycin. The aim of the present study was to search for the pathways involved in mutagen sensitivity. Lymphoblastoid cell lines of seven individuals with low mutagen sensitivity were compared with seven individuals with a high score. RNA was isolated from cells exposed to bleomycin (4 hours) and from unexposed cells. Microarray analysis (19K) was used to compare gene expression of insensitive and sensitive cells. The profile of most altered genes after bleomycin exposure, analyzed in all 14 cell lines, included relatively many genes involved in biological processes, such as cell growth and/or maintenance, proliferation, and regulation of cell cycle, as well as some genes involved in DNA repair. When comparing the insensitive and sensitive individuals, other differentially expressed genes were found that are involved in signal transduction and cell growth and/or maintenance (e.g., BUB1 and DUSP4). This difference in expression profiles between mutagen-sensitive and mutagen-insensitive individuals justifies further studies aimed at elucidating the genes responsible for the development of sporadic cancers. (Mol Cancer Res 2006;4(2):71–7)
Blocking the Protease-Activated Receptor 1-4 Heterodimer in Platelet-Mediated Thrombosis
Authors: Leger Andrew J. , Jacques Suzanne L. , Badar Jehangir , Kaneider Nicole C. , Derian Claudia K. , Andrade-Gordon Patricia , Covic Lidija , Kuliopulos Athan 
Published: February 2006

Background—Thrombin is the most potent agonist of platelets and plays a critical role in the development of arterial thrombosis. Human platelets express dual thrombin receptors, protease-activated receptor (PAR) 1 and PAR4; however, there are no therapeutic strategies that effectively target both receptors.Methods and Results—Platelet aggregation studies demonstrated that PAR4 activity is markedly enhanced by thrombin–PAR1 interactions. A combination of bivalirudin (hirulog) plus a novel PAR4 pepducin antagonist, P4pal-i1, effectively inhibited aggregation of human platelets to even high concentrations of thrombin and prevented occlusion of carotid arteries in guinea pigs. Likewise, combined inhibition of PAR1 and PAR4 with small-molecule antagonists and pepducins was effective against carotid artery occlusion. Coimmunoprecipitation and fluorescence resonance energy transfer studies revealed that PAR1 and PAR4 associate as a heterodimeric complex in human platelets and fibroblasts. PAR1-PAR4 cofactoring was shown by acceleration of thrombin cleavage and signaling of PAR4 on coexpression with PAR1.Conclusions—We show that PAR1 and PAR4 form a stable heterodimer that enables thrombin to act as a bivalent functional agonist. These studies suggest that targeting the PAR1-PAR4 complex may present a novel therapeutic opportunity to prevent arterial thrombosis.
Comparative morphological and serological studies of three Anatolian Mountain frogs, Rana macrocnemis, R. camerani and R. holtzi (Anura, Ranidae)
Authors: Atatür Mehmet Kutsay , Kaya Uğur , Arikan Hüseyin , Çevik İbrahim Ethem 
Published: February 2006

AbstractThree currently recognized species of Anatolian mountain frogs were analyzed for species boundaries. Meristic and proportional measurement data of three populations, including two topotypical ones, were evaluated using both univariate and discriminant analyses, and blood-serum samples were analyzed electrophoretically with polyacrylamide-disc electrophoresis. The results indicate that only two distinct mountain frog species inhabit Anatolia. We recommend that R. camerani from Mt Erciyes should be recognized as a synonym of R. macrocnemis.
The Phylogenetic Relationships of the Chinese and Vietnamese Waterfall frogs of the genus Amolops
Authors: Orlov Nikolai , Murphy Robert , Liu Wanzhao , Ngo Andre , Lathrop Amy 
Published: February 2006

AbstractRanid frogs of the genus Amolops occur in Southeast Asia and are typically found near waterfalls. Their phylogenetic relationships have not been resolved. We include 2,213 aligned nucleotide sites of the 12S, 16S and tRNAval gene regions of the mitochondrial DNA genome from 43 individuals of Chinese and Vietnamese Amolops, Huia, Hylarana, Meristogenys, Odorrana and Rana. The outgroup species were from the genera Chaparana, Limnonectes, Nanorana, and Paa. The data were analyzed within the framework of a refutationist philosophy using maximum parsimony. Four clades of waterfall frogs were resolved. Meristogenys was not resolved as the sister group to either Huia nor Amolops. The hypothesis of evolutionary relationships placed Amolops chapaensis and Huia nasica in the genus Odorrana.
Variable number tandem repeats in the mitochondrial DNA Control region of the Chinese alligator, Alligator sinensis
Authors: Fang Shengguo , Xu Qianghua 
Published: February 2006

AbstractVariable number tandem repeats (VNTRs) are present in the control region of mitochondrial DNA (mtDNA) of the alligatorid species; however, the evolutionary dynamics of the repetitive sequences and the significance of the VNTRs in the context of genetic monitoring of these species are not well explored. The Chinese alligator, Alligator sinensis is critically endangered and is now largely in captive breeding. Previous studies in mitochondrial genes revealed little genetic diversity existing within the populations. We reported here the structural variation and evolutionary features of mtVNTRs in the Changxing population of the species. The mtVNTRs contained 676∼785 base pairs, made up by 5 distinct motifs repeated 31∼36 times in 32 individuals examined. The motifs were 21∼22 nts in length, with high sequence similarity between each other and with those of the American alligator (Alligator mississippiensis), indicating origination of the mtVNTRs from a single ancestral duplication unit in both species. The 5′ and 3′ portions of the repetitive sequences in the Chinese alligator were very much conserved among the individuals, while those in the middle showed a higher degree of sequence variation. The frequency of each motif appearing in the mtVNTRs showed positive correlation to the binding energy of the potential secondary structure the motif could adopt. 17 VNTR types, of which, 6 from the second generation and 12 from the third generation were identified from the samples. Analysis of the multiple VNTR types showed a high level of stochastic mutation within each generation. The suitability of the mtVNTRs as a marker to monitor the genetic differentiation of the Chinese alligator was also discussed.
Hemipenial morphology of five Asian pitvipers, with a discussion on their taxonomy
Authors: Guo Peng , Zhao Hui , Zhao Ermi , Lu Shunqing , Huang Song 
Published: February 2006

AbstractThe hemipenial morphology of five Asian pitvipers, Protobothrops mucrosquamatus, Protobothrops jerdonii, Ovophis zayuensis, Ovophis monticola and Viridovipera yunnanensis, are described and illustrated. Of them, the hemipenes of the first three species have been briefly reported in Chinese Journal of Zoology in Chinese. The results reveal that five species are different in hemipenial structures. The differences between Ovophis zayuensis and Ovophis monticola, and between Viridovipera yunnanensis and Viridovipera stejnegeri, further confirm the validation of Ovophis zayuensis and Viridovipera yunnanensis respectively.
Rod-Shaped Bivalents indicate new assemblage among Anatolian Water Frog Populations
Authors: Mutaf Beria Falakali , Keskin Nurşen Alpagut 
Published: February 2006

AbstractThe general features of the mitotic and meiotic chromosomes analysed in 91 frogs belonging to nine water frog populations distributed in Southwest Anatolia. The differences found in mitotic and meiotic chromosomes revealed the existence of two groups among the populations: the first "Aegean Group" includes those from Izmir, Bulca, Pazarağaç, and the second – "Lake District Group" from Eber, Akşehir, Gelendost, Eğirdir, Gölcük, and Beyşehir populations. The major distinction appeared in the number of the rod-shaped bivalents in metaphase I, with only one in the "Aegean Group" compared to one or two in the "Lake District Group". This result indicates a new assemblage among Anatolian water frogs and strengthens the suggestion that the "Lake District Group" that have one or two rod shaped bivalents in metaphase I due to the inclusion of hybrid lineages containing both parental genomes. It is clear that at least two separate species are present in Anatolia; one of them is possibly Rana ridibunda from the north and the second is closer to the Balkan species Rana epeirotica and Rana shqiperica.
Asynchronous spermatogenesis and biennial female cycle of the viviparous lizard Phymaturus antofagastensis (Liolaemidae): reproductive responses to high altitudes and temperate climate of Catamarca, Argentina
Authors: Ibargüengoytía Nora , Boretto Jorgelina 
Published: February 2006

AbstractThis paper studies minimum SVL at sexual maturity, sexual dimorphism, operational sex ratio, male and female reproductive cycles, and litter size of viviparous Phymaturus antofagastensis, a species living at high altitude in the temperate climate of Catamarca, Argentina. Males reached sexual maturity at 90 mm, and females at 79 mm. Adult males attained significantly larger body size and head width than adult females. Histological analysis showed asynchrony in spermatogenesis timing among males and spermatozoa storage in epididymis throughout the reproductive season (spring to early autumn). Females showed a biennial reproductive cycle taking at least one activity season to perform either vitellogenesis or pregnancy. Brood size resulted in two offspring, a condition similar to other species of the genus, with births occurring in late summer. The reproductive cycle of Phymaturus antofagastensis shows a new response in males and females to harsh environments characterized by short activity seasons, long hibernation periods and large daily and seasonal thermal fluctuations.
Interpopulational variation in sexual dimorphism, reproductive output, and parasitism of Liophis miliaris (Colubridae) in the Atlantic forest of Brazil
Authors: Pizzatto Lígia , Marques Otavio 
Published: February 2006

AbstractSexual maturity, sexual dimorphism, reproductive output, and parasitism of the colubrid snake Liophis miliaris were compared among populations inhabiting four regions of Brazil: (1) northern coastal Atlantic forest, (2) southern coastal Atlantic forest, (3) northern inland Atlantic forest (4) southern inland Atlantic forest. Females delayed maturity and attained larger body sizes than males in all regions. Males and females from northern Atlantic forest were smaller and attained maturity with a smaller body size than males of other regions. The sexual size dimorphism index ranged from 0.19 to 0.23 and was lowest in the northern Atlantic forest. There was no sexual dimorphism in head length in any of the populations studied. Clutch size was similar in all populations and increased with maternal body size. The reproductive frequency was lower in the northern coastal Atlantic forest and in contrast to the other regions, tended to increase with female body size. The nematoda Ophidiascaris sp. and cystacanths of Oligacanthorynchus spira (Acanthocephala) occurred equally in both sexes. Fewer snakes from the northern coastal Atlantic forest were infested by parasites compared to the other regions and parasitism apparently did not influence reproduction.
Insular morphological divergence in the lizard Liolaemus pictus (Liolaemidae)
Authors: Méndez Marco , Veloso Alberto , Vidal Marcela 
Published: February 2006

AbstractLiolaemus pictus is a widely distributed arboreal lizard species in southern Chile. Within this species, mainland and island subspecies have been described mainly based on external morphological characters, however, their diagnostic characters have not been accurately demarcated. We used both traditional and geometric morphometrics to study the morphological divergence in L. pictus subspecies. Since geographic isolation can be related to environmental variation (e.g., variation in abundance and richness of insects or fruits), we predict that the L. pictus morphology could vary in head shape between mainland and island localities.Our results show morphological divergence in all variables analyzed among the island and mainland localities. The traditional morphometric approach reveals differences between populations from the mainland and island localities, where the mainland populations show a larger head size. Geometric morphometric data indicate that the eye orbits of the island specimens are more extended than in the mainland specimens in the dorsal view; this is probably related to a different capacity of substrate used. Also, in the lateral view, the eye orbits are extended and the head shape is less dorso-ventrally compressed in the island locality than in mainland populations and the terminal mouth position is more posterior in island specimens. We suggest that the morphological variation between mainland and island localities could be related to the fact that these populations were isolated during the last maximum glacial period in southern Chile, a period in which geomorphologic and bioclimatic features of this area were modified forming the present archipelago.
Potential use of anurans as indicators of biological quality in upstreams of central Italy
Authors: Lebboroni Marco , Chelazzi Guido , Bellavita Massimo , Ricchiardino Giulia 
Published: February 2006

AbstractThe headwater streams of two basins in central Italy were sampled in randomly selected reaches (n = 59) to quantify tadpole occurrence. Environmental and physico-chemical data were collected for each reach. Macrobenthos were also sampled to obtain quantitative indices of biological quality (IBE and BMWP). A longitudinal zonation was evident for the three most common amphibian species found (Rana italica, Bufo bufo and Rana kl. esculenta, from higher to lower altitude). A good concordance was recorded between the occurence of single species, in this order, and a decreasing value of water quality as computed by BMWP. In both basins, the average BMWP and IBE scores for reaches where R. italica occurred alone corresponded to the standard judgement of 'excellent' to 'good' biological water quality. R. italica was suggested as a potential bioindicator for small headwater streams.
Allometry of reproduction of Podocnemis expansa in Southern Amazon basin
Authors: Piña Carlos , Bonach Kelly , Verdade Luciano 
Published: February 2006

AbstractPodocnemis expansa (giant Amazon freshwater turtle) is the biggest freshwater turtle of South America. Like in other reptiles, the nest of P. expansa is a hole in the sand deep enough to avoid predators and extremes of temperature and humidity. However, nesting habitat selection in reptiles has effects on incubation success and on hatchlings. Female body-size is also related to the size and shape (i.e., form) of the nest, which might in theory be related to the female reproductive success. In this study we established allometric relationships between female body size and nest form. Fieldwork was carried out in nesting beaches of Araguaia and Crixás-Açu Rivers in Southern Amazon basin, Brazil, from September to December 2000. As a result, we can establish that nest form does not affect reproductive success in the species, but female body length is positively related to egg mass and clutch size.
Negotiating Measures to Manage Biological Risks: The Need for New Thinking and New Approaches
Authors: Moodie Michael 
Published: March 2006

AbstractThis essay considers the difficulties confronting the international community in addressing the challenge of biological weapons through multilateral negotiations. After a brief review of the Biological and Toxin Weapons Convention, the article addresses four categories of factors that help understand the relative lack of success: those related to the structure and conduct of the negotiating process, those stemming from the unique nature of the life sciences, those associated with domestic political dynamics in the United States, and those associated with changes in the structure and dynamics of the international system. It closes with reflections on how the international community can embed negotiations in a broader strategy for bolstering capabilities to manage the security risks related to the advances of the life sciences and related technology.
Realism, Politics and Culture in Middle East Arms Control Negotiations
Authors: Steinberg Gerald 
Published: March 2006

AbstractThe history of arms control efforts in the Middle East consists of numerous initiatives, but very limited results. From the first efforts to negotiate WMD limits and non-proliferation arrangements in the 1960s, through various regional initiatives, frameworks, proposals, discussions, and negotiations, the obstacles to agreement on mutual limitations remained dominant. Frequent discussions in the UN of a Middle East Nuclear Free Zone (MENWFZ), the multi-lateral Arms Control and Regional Security (ACRS) talks initiated during the 1991 Middle East Peace Conference, and the regional dimensions of global frameworks such as the NPT, CWC, and CTBT have all failed to produce results.Detailed analysis of these efforts highlights the impact of realist security-based factors, the structure and process of the interactions, as well as the cultural and domestic political dimensions. The existential conflicts, reflected in protracted territorial disputes and denials of legitimacy and compounded by a fundamental asymmetry, created a zero-sum framework in the region. The region is characterized by a great deal of instability and competition; this situation, in turn, contributed to the efforts to acquire WMD. In terms of domestic politics, the regional cooperation required for arms limitation is often inconsistent with the dominant articulated political interests and regime perspectives. In addition, misunderstandings and misperceptions frequently occur due to the complexities of cross-cultural communications in the Middle East. Numerous dialogues have not narrowed the gaps or transformed the zero-sum frameworks into cooperative ones. Hopes for the creation of successful regional mechanisms for limiting arms depend on overcoming the obstacles encountered in past efforts.
Association of Tropical Cirrus in the 10–15-km Layer with Deep Convective Sources: An Observational Study Combining Millimeter Radar Data and Satellite-Derived Trajectories
Authors: Mace Gerald G. , Deng Min , Soden Brian , Zipser Ed 
Published: March 2006

Abstract
In this paper, millimeter cloud radar (MMCR) and Geosynchronous Meteorological Satellite (GMS) data are combined to study the properties of tropical cirrus that are common in the 10–15-km layer of the tropical troposphere in the western Pacific. Millimeter cloud radar observations collected by the Atmospheric Radiation Measurement program on the islands of Manus and Nauru in the western and central equatorial Pacific during a 12-month period spanning 1999 and 2000 show differences in cirrus properties: over Manus, where clouds above 7 km are observed 48% of the time, the cirrus are thicker and warmer on average and the radar reflectivity and Doppler velocity are larger; over Nauru clouds above 7 km are observed 23% of time. To explain the differences in cloud properties, the relationship between tropical cirrus and deep convection is examined by combining the radar observations with GMS satellite-derived back trajectories. Using a data record of 1 yr, it is found that 47% of the cirrus observed over Manus can be traced to a deep convective source within the past 12 h while just 16% of the cirrus observed over Nauru appear to have a convective source within the previous 12 h. Of the cirrus that can be traced to deep convection, the evolution of the radar-observed cloud properties is examined as a function of apparent cloud age. The radar Doppler moments and ice water path of the observed cirrus at both sites generally decrease as the cirrus age increase. At Manus, it is found that cirrus during boreal winter typically advect over the site from the southeast from convection associated with the winter monsoon, while during boreal summer, the trajectories are mainly from the northeast. The properties of these two populations of cirrus are found to be different, with the winter cirrus having higher concentrations of smaller particles. Examining statistics of the regional convection using Tropical Rainfall Measuring Mission (TRMM), it is found that the properties of the winter monsoon convection in the cirrus source region are consistent with more intense convection compared to the convection in the summer source region.