bluuebunny/crossref_metadata_2025 huggingface dataset:
Homeland Interests, Hostland Politics: Politicized Ethnic Identity among Middle Eastern Heritage Groups in the United States
Authors: Wald Kenneth D.
Published: May 2008

Why do ethnic diasporas in the United States differ in their readiness for political mobilization on behalf of homeland interests? This study develops a tiered model of politicized ethnic identity emphasizing both individual-level traits and group/collective properties. Using Zogby “Culture Polls,” the theory is tested on three Middle Eastern heritage groups in the United States (Jews, Arab Christians, Arab Muslims). Empirical analysis confirms that individuals differ in their readiness for mobilization around Middle East issues based on the strength of ties to the ethnic community and, net of such differences, each group varies based on the contexts of exit and reception it faced at the time of immigration. The findings suggest that studies of diaspora influence on American foreign policy need to take account of the mass base rather than focus exclusively on elite behavior.
“No Thanks, We're Full”: Individual Characteristics, National Context, and Changing Attitudes toward Immigration
Authors: Wilkes Rima , Guppy Neil , Farris Lily
Published: May 2008

In this paper we examine how individual-level characteristics and national context affect attitudes toward immigration. Although many previous studies have compared attitudes toward immigration across countries, little attention has been paid to how attitudes may be affected by changes within a country over time. We take advantage of seventeen national Canadian Gallup surveys to consider how differences in national economic conditions and changing immigration flows affect attitudes and changes in attitudes between 1975 and 2000. While the state of the national economy affects attitudes this is not the case for the rate of immigration. Rather than affecting some groups more than others the state of the economy has a relatively uniform effect across groups. Our results also show that far from being a continuum, being anti-immigration and being pro-immigration are qualitatively different. Interest, ideology, and the national economy affect anti-immigration sentiments, but only ideology affects pro-immigration sentiments.
Biological basis for soft tissue management in implant dentistry
Authors: Yeung SCH
Published: May 2008

Good aesthetic finish of implant/restorations requires healthy peri‐implant soft tissue at the appropriate location. The relevance of the peri‐implant soft tissue seal, the biological width, the keratinized gingival zone and the need for effective plaque control in order to maintain peri‐implant soft tissue health were discussed. The presence of a soft tissue seal/cuff around dental implants and abutments and its role in defense against infection were convincingly demonstrated in animal studies. In order to achieve long‐term stable peri‐implant health, it is important to achieve an adequate soft tissue seal around dental implant/restorations. The constant dimension of a biological width (of the soft tissue) often dictates where the final gingival margin will be. It is therefore not surprising that the position and stability of the alveolar bone ridge surrounding dental implants ultimately determines where the gingival margin rests. For dental implant restorations in the aesthetic zone, this is a crucial variable for the clinician to understand and deliver. Available data so far suggest that with good oral hygiene, peri‐implant soft tissue health can be maintained irrespective if a keratinized gingival tissue zone surrounding implant/restoration is present. In reality, good oral hygiene is very difficult to achieve around dental restorations without the protection of a band of keratinized gingival tissue. Studies on peri‐implantitis and peri‐implant mucositis further demonstrated the causal relationship between dental plaque accumulation and peri‐implant inflammation. It is therefore imperative that long‐term maintenance care of dental implants and implant supported dental restorations should include a strict regime of plaque control and monitoring.
Acute and chronic effects of vitamin C on endothelial fibrinolytic function in overweight and obese adult humans
Authors: Van Guilder Gary P. , Hoetzer Greta L. , Greiner Jared J. , Stauffer Brian L. , DeSouza Christopher A.
Published: May 2008

We determined the effects of acute intra‐arterial vitamin C administration and chronic oral vitamin C supplementation on the capacity of the endothelium to release t‐PA in overweight and obese adults. Net endothelial t‐PA release was determined in vivo in response to intrabrachial infusions of bradykinin and sodium nitroprusside in 33 sedentary adults: 10 normal‐weight (BMI: 23.4 ± 0.5 kg m−2; 7M/3F); and 23 overweight/obese (BMI: 31.2 ± 0.8 kg m−2; 15M/8F). In 10 normal weight and eight overweight/obese adults the dose–response curves to bradykinin and sodium nitroprusside were repeated with a coinfusion of the antioxidant vitamin C (24 mg min−1). Seventeen of the 23 overweight/obese adults completed a 3 month chronic oral vitamin C (500 mg day−1) supplementation intervention. Intra‐arterial administration of vitamin C significantly potentiated t‐PA release in overweight/obese adults. Net release of t‐PA was ∼95% higher (P < 0.01) after (from −0.9 ± 1.1 to 94.6 ± 16.2 ng (100 ml tissue)−1 min−1) compared with before (from −0.8 ± 0.8 to 49.9 ± 7.7 ng (100 ml tissue)−1 min−1) vitamin C administration. Daily vitamin C supplementation significantly increased t‐PA release in overweight/obese adults (from 0.2 ± 0.9 to 48.2 ± 6.5 ng (100 ml tissue)−1 min−1) before supplementation versus (0.3 ± 0.5 to 66.3 ± 8.7 ng (100 ml tissue)−1 min−1) after supplementation. These results indicate that the antioxidant vitamin C favourably affects the capacity of the endothelium to release t‐PA in overweight/obese adults. Daily vitamin C supplementation represents an effective lifestyle intervention strategy for improving endothelial fibrinolytic regulation in this at‐risk population.
Distribution and Dispersal of the Zebra Mussel (Dreissena polymorpha) in the Great Lakes Region
Authors: Griffiths Ronald W. , Schloesser Donald W. , Leach Joseph H. , Kovalak William P.
Published: May 2008

Dreissena polymorpha (Pallas), a small mussel common throughout most of Europe, was discovered in June of 1988 in the southern part of Lake St. Clair. Length–frequency analyses of populations from the Great Lakes and review of historical benthic studies suggest that the mussel was introduced into Lake St. Clair in late 1986, probably as a result of the discharge of ballast water from an ocean-crossing vessel. Following the 1990 reproductive season, Dreissena populations ranged from the head of the St. Clair River, through Lake St. Clair, the Detroit River, Lake Erie, the Welland Canal, and the Niagara River to the western basin and southern shoreline of Lake Ontario. Isolated populations were found in the St. Lawrence River and in harbours in Lakes Huron, Michigan, and Superior. The rapid dispersal of this organism has resulted from its high fecundity, pelagic larval stage, bysso-pelagic drifting ability of juveniles, and human activities associated with commercial shipping, fishing, and boating (research and pleasure). Virtually any waterbody that can be reached by boaters and fisherman within a few days travel of the lower Great Lakes, particularly Lake Erie, seems to be at risk of being invaded by this nuisance species.
Historical Nutrient Enrichment of Lake Ontario: Paleolimnological Evidence
Authors: Schelske Claire L.
Published: May 2008

Recent studies of Lake Ontario show four periods of nutrient enrichment that can be identified from the sediment record in this phosphorus-limited system: pristine phosphorus loads (early 1800s before European settlement), moderate increase in phosphorus loading after settlement (beginning approximately 1850), exponential increase in phosphorus loading from urban sources (approximately 1940–70), and decreased phosphorus loading as the result of phosphorus abatement strategies (beginning in mid-1970s). Paleolimnological data are used to infer new paradigms about historical dynamics and cycling of major nutrients. The temporal pattern of organic carbon production closely parallels changes in phosphorus loading. Silica supplies which were replete for diatom production before forest clearance in the mid-1800s became limiting for diatom production in the summer epilimnion after 1865 and in the water column after 1950. Silica reserves were depleted by increased diatom production and sedimentation that resulted from increased phosphorus loading. Biologically induced precipitation of calcite began after 1940 as an indirect effect of increased urban phosphorus loading on primary productivity. Calcite began to be precipitated when historical increases in CO2utilized for primary productivity increased epilimnetic pH and the calcium carbonate saturation product was exceeded.
Changes in the Nearshore and Offshore Zooplankton Communities in Lake Ontario: 1981–88
Authors: Johannsson Ora E. , Mills Edward L. , O'Gorman Robert
Published: May 2008

We examined trends and factors influencing changes in nearshore and offshore zooplankton abundance and composition in Lake Ontario between 1981 and 1988. In the nearshore (southshore and eastern basin), zooplankton abundance decreased and shifts occurred in the relative abundances of Bosmina longirostris and Daphnia retrocurva (eastern basin) and Daphnia retrocurva and Daphnia galeata mendotae (southshore). These changes could have resulted from increased vertebrate predation or reduced food resources which intensified the effects of predation. In the offshore, the first appearance (FA) of the larger, less common cladoceran species occurred earlier in the season as of 1985. FA was correlated with cumulative epilimnetic temperature (CET) and the catch per unit effort (CPUE) of alewife (Alosa pseudoharengus) [Formula: see text] caught in U.S. waters in the spring. In 1987, when CET was high and CPUE of alewife [Formula: see text] was low, large populations of these cladocerans developed in June and July. Bythotrephes cederstroemi, a recent invader in the Great Lakes, was abundant only in 1987 when the CPUE of alewife was lowest. Changes in zooplankton abundance, development, and composition along the nearshore–offshore gradient reflected effects of temperature, habitat, and planktivory on the community.
Discrimination of intra- and inter-specific forage quality by collared pikas (Ochotona collaris)
Authors: Morrison S. F. , Hik D. S.
Published: May 2008

The specific nutritional characteristics by which herbivores evaluate their foraging options are complex. We experimentally manipulated the crude protein and water content of two forage species ( Carex consimilis Holm. (= Carex bigelowii Torr. ex Schwein.) and Polygonum bistorta L.) commonly cached by collared pikas ( Ochotona collaris (Nelson, 1893)) to determine their influence on inter- and intra-specific forage selection. Preference data were collected for 27 pikas using cafeteria-style feeding trials in a randomized block design. A three-way interaction (species × protein × water) suggested that pikas made conditional forage selection decisions while caching these plants. The interaction was driven by greater selection for fresh rather than dried C. consimilis when both were not fertilized. Water content had no effect on the selection of either fertilized C. consimilis or fertilized P. bistorta. Overall, our results indicate that pikas made subtle decisions about their selection of vegetation during caching, based on variation in nitrogen and water content in addition to species-specific selection criteria. Further, our results imply that tests of foraging theory may need to consider intra-specific variation in forage characteristics, as well as inter-specific ranking of forage species.
Anti-bat flight activity in sound-producing versus silent moths
Authors: Ratcliffe John M. , Soutar Amanda R. , Muma Katherine E. , Guignion Cassandra , Fullard James H.
Published: May 2008

The ultrasonic clicks produced by some tiger moths — all of which possess bat-detecting ears — are effective acoustic aposematic or mimetic signals, conferring protection against aerial hawking bats. Clicks are produced in response to bat echolocation calls. Palatable, silent non-tiger-moth species with bat-detecting ears fly away from distant bats and effect erratic flight maneuvers or stop flying in response to the calls of bats nearby. These flight responses are also an effective defense. We tested the hypotheses that sound-producing tiger moths (i) do not exhibit the reduction in flight time typical of silent, palatable moth species when presented with ultrasound simulating bat echolocation calls and (ii) exhibit more flight activity than silent, palatable species both in the presence and absence of ultrasound. We found that sound-producing tiger moths did not significantly reduce flight activity to bat-like sounds and that silent tiger moths and other noctuoid species did. We also found that sound-producing tiger moths flew significantly more than did silent species in both the presence and the absence of ultrasound. The benefits of acoustic aposematism may allow sound producers to spend more time aloft than silent species and thereby improve their chances of successful reproduction.
The effects of high ungulate densities on foraging choices by beaver (Castor canadensis) in the mixed-wood boreal forest
Authors: Hood G. A. , Bayley S. E.
Published: May 2008

In some areas of North America previous management policies have created competition between beaver ( Castor canadensis Kuhl, 1820) and ungulates, resulting in dramatic declines in beaver populations. Some authors attribute this decline to competitive exclusion. Generally, the less niche overlap between competitors, the lower potential competition between them. Differences between foraging behaviour of beaver and ungulates suggest that they could not compete to the point of either competitive exploitation or complete exclusion except in restricted habitats. We tested this assumption under two levels of foraging intensity by ungulates by examining the effects of resource competition on beaver forage choices in the context of central place foraging theory. Ungulate densities and foraging intensity within Elk Island National Park (EINP) in Alberta, Canada, were significantly higher than those immediately adjacent to the park, where foraging pressure was lower. Within EINP, forage availability (e.g., stem densities and stem diameters) of many woody plants preferred by beaver, such as Populus L. and Salix L., were depressed by intense foraging by ungulates. Beaver adapted to the effects of high ungulate densities on forage resources by adapting their foraging behaviour. This finding suggested that competitive exploitation, rather than exclusion, exists in EINP. EINP is a productive system that offers an array of forage species, which potentially buffers the effects of competition between ungulates and beaver.
Ecological predictions lead to the discovery of a benthic–limnetic sympatric species pair of threespine stickleback in Little Quarry Lake, British Columbia
Authors: Gow J. L. , Rogers S. M. , Jackson M. , Schluter D.
Published: May 2008

Sympatric species pairs of benthic and limnetic threespine stickleback ( Gasterosteus aculeatus L., 1758 complex) are an important example of the role of ecology in speciation in nature. Four endemic pairs are known and each appears to have diverged independently as a consequence of adaptation to alternative environments. Using specific ecological and physical attributes hypothesized to be important to their evolution, we focused a search for further species pairs. Now, two decades after the last discovery, we describe another benthic–limnetic species pair from Little Quarry Lake on Nelson Island, British Columbia, Canada. Bimodality of genetic admixture values provides evidence of strong reproductive isolation between two morphological and genetic clusters, supporting the existence of a sympatric species pair within this lake. Close correspondence in shape to extant benthic and limnetic species pairs confirm their status as such. The remarkable similarity between them and other benthic and limnetic species pairs in levels of morphological differentiation, as well as extent of admixture and hybridization, points to similar processes underlying their origin. This discovery serves as an important reminder of the specificity of ecological factors that promote and maintain biodiversity, as well as the value of habitat conservation.
Acute norepinephrine reuptake inhibition decreases performance in normal and high ambient temperature
Authors: Roelands Bart , Goekint Maaike , Heyman Elsa , Piacentini Maria Francesca , Watson Philip , Hasegawa Hiroshi , Buyse Luk , Pauwels Frank , De Schutter Guy , Meeusen Romain
Published: May 2008

Combined inhibition of dopamine (DA)/norepinephrine (NE) reuptake improves exercise performance and increases core temperature in the heat. A recent study demonstrated that this effect may primarily be related to increased DA activity. NE reuptake inhibition (NERI), however, has received little attention in humans, certainly in the heat, where central fatigue appears to be a main factor influencing performance. Therefore the present study examines the effect of NERI (reboxetine) on exercise capacity, thermoregulation, and hormonal response in normal and high temperature. Nine healthy well-trained male cyclists participated in this study. Subjects ingested either placebo (Pla; 2 × 8 mg) or reboxetine (Rebox; 2 × 8 mg). Subjects exercised in temperate (18°C) or warm (30°C) conditions and cycled for 60 min at 55% Wmax immediately followed by a time trial (TT; Pla18/Rebox18; Pla30/Rebox30) to measure exercise performance. Acute NERI decreased power output and consequently exercise performance in temperate ( P = 0.018) and warm ( P = 0.007) conditions. Resting heart rate was significantly elevated by NERI (18°C: P = 0.02; 30°C: P = 0.018). In Rebox18, heart rate was significantly higher than in the Pla18, while in the heat no effect of the drug treatment was reported during exercise. In Rebox30, all hormone concentrations increased during exercise, except for growth hormone (GH), which was significantly lower during exercise. In Rebox18, prolactin (PRL) concentrations were significantly elevated; GH was significantly higher at rest, but significantly lower during exercise. In conclusion, manipulation of the NE system decreases performance and modifies hormone concentrations, thereby indicating a central NE effect of the drug. These findings confirm results from previous studies that predominantly increased DA activity is important in improving performance.
Radiation hybrid (RH) and HAPPY mapping in plants
Authors: Riera-Lizarazu O. , Vales M.I. , Kianian S.F.
Published: May 2008

Radiation hybrid (RH) and HAPPY mapping are two technologies used in animal systems that have attracted the attention of the plant genetics community because they bridge the resolution gap between meiotic and BAC-based physical mapping that would facilitate the analysis of plant species lacking substantial genomics resources. Research has shown that the essence of these approaches can be applied and that a variety of strategies can be used to produce mapping panels. Mapping panels composed of live plants, protoplast fusion cultures, and sub-genomic DNA samples have been described. The resolution achievable by RH mapping panels involving live-plant derivatives of a monosomic maize (Zea mays) chromosome 9 addition in allohexaploid oat (Avena sativa), a monosomic chromosome 1D addition in allotetraploid durum wheat (Triticum turgidum), and interspecific hybrids between two tetraploid cotton species (G. hirsutum and G. barbadense), has been estimated to range from 0.6 to 6 Mb. On the other hand, a more comprehensive evaluation of one panel from durum wheat suggests that a higher mapping resolution (∼200 kb) is possible. In cases involving RH mapping panels based on barley (Hordeum vulgare)-tobacco (Nicotiana tabacum) protoplast fusions or a HAPPY mapping panel based on genomic DNA from Arabidopsis thaliana, the potential mapping resolution appears to be higher (50 to 200 kb). Despite these encouraging results, the application of either RH or HAPPY mapping in plants is still in the experimental phase and additional work is clearly needed before these methods are more routinely utilized.
Comparison of Ocular Surface Side Effects of Topical Travoprost and Bimatoprost
Authors: Alagöz Gürsoy , Bayer Atilla , Boran Çetin , Serin Didem , Kükner Aysel , Elçioğlu Mustafa
Published: May 2008

Purpose: To compare the subjective symptoms, conjunctival hyperemia, tearing response and conjunctival cytological changes secondary to topical administration of bimatoprost and travoprost for 6 months. Methods: Newly diagnosed primary open-angle glaucoma patients were randomly prescribed bimatoprost (35 cases) or travoprost (42 cases). Two patients in each group were excluded because they did not appear at their appointments regularly. Thus, 33 and 40 patients completed the study in the bimatoprost and travoprost groups, respectively. Redness, itching, foreign-body sensation, pain and discomfort were assessed by a questionnaire, and patients were examined for conjunctival hyperemia. Schirmer’s I and break-up time tests were performed, and impression cytology of conjunctiva was evaluated. Results: Subjective symptoms were similar in both groups. The only subjective symptom that changed significantly was redness. The change in conjunctival hyperemia along the study period correlated with the patient-reported redness in both groups, being highest on day 30. Schirmer’s test I and break-up time did not change with time and were similar in both groups. The impression cytology grade increased with time in both groups with the only significant difference between groups on day 90 (higher in the bimatoprost group). Conclusion: We observed conjunctival hyperemia as the most common side effect of bimatoprost and travoprost. Tear film functions were not affected by these drugs while cytological alterations were.
Evaluation of the Optic Nerve Head with the Heidelberg Retina Tomograph in Diabetes Mellitus
Authors: Tekeli Oya , Turaçlı M. Erol , Atmaca Leyla Suna , Elhan Atilla Halil
Published: May 2008

Background: To evaluate the optic nerve head by means of the Heidelberg retina tomograph (HRT) in patients with diabetes mellitus (DM). Methods: The study group consisted of 47 patients with DM [group 1; 29 patients without diabetic retinopathy (DR) and 18 patients with non-proliferative DR] and 50 normal subjects (group 2). All patients and controls underwent a complete ophthalmological examination, and the optic nerve head topography of both eyes was evaluated by using HRT-I. One eye of these cases was randomly selected for statistical analysis. Glycosylated haemoglobin (HbA1c) levels of all the study participants were measured. Results: The HRT parameters were similar between diabetic and control groups (p > 0.05). In group 1, in the patients with duration of diabetes ≤10 years, when compared with the patients with duration of diabetes >10 years, we did not detect any statistically significant difference between the HRT parameters (p > 0.05). There was no statistically significant correlation between HBA1c levels and rim volume (r = –0.078, p = 0.601), and mean retinal nerve fibre layer thickness (r = 0.058, p = 0.700) in DM patients. Conclusion: These results suggest that non-glaucomatous diabetic patients had no decreased neuroretinal rim when compared with non-diabetic patients.
Subretinal Hemorrhages Secondary to Age-Related Macular Degeneration: Psychological and Vision-Related Functional Perspectives
Authors: Mozaffarieh Maneli , Sacu Stefan , Benesch Thomas , Wedrich Andreas
Published: May 2008

Purpose: To assess psychological, visual and functional aspects associated with subretinal hemorrhages secondary to age-related macular degeneration (AMD). Method: In this prospective, comparative, longitudinal study, 90 eyes of 90 patients with a subretinal hemorrhage, secondary to AMD, of at least 1 disk diameter were treated with recombinant tissue plasminogen activator (rTPA) and gas, and compared to 25 eyes of 25 controls. Outcome measures were: (1) visual acuity, (2) self-reported vision-related quality of life (Visual Function 14-item questionnaire) and (3)Hospital Anxiety and Depression (HAD) scores. Visual acuity and questionnaire responses were recorded prior to as well as 2 weeks and 4 months after treatment. Results: Improvements across objective visual acuity and vision-related functional measures, assessed at 2 weeks and 4 months, were significantly higher in patients who had rTPA and gas injections than in controls (p < 0.01). Patients were significantly more distressed at their 2-week follow-up in comparison to controls (HAD scores p < 0.01). Comparisons to controls showed no significant difference in psychological scores at the 4-month follow-up (p > 0.32). Conclusions: Patients with subretinal hemorrhages secondary to AMD are psychologically distressed as a result of acute loss of vision. More attention should be given to strategies that teach patients to cope with acute vision loss and thereby psychological disorder.
Impact and Perspective on Chronic Kidney Disease in an Asian Developing Country: A Large-Scale Survey in North Vietnam
Authors: Ito Jun , Dung Dinh Thi Kim , Vuong Mai Tuyet , Tuyen Do Gia , Vinh Le Danh , Huong Nguyen Thi , Ngoc Tran Bich , Ngoc Nguyen Thi Bich , Hien Mai Thi , Hao Dang Duc , Oanh Lam Thi Kim , Lieu Do Thi , Fujisawa Masato , Kawabata Masato , Shirakawa Toshiro
Published: May 2008

Background: The prevalence of chronic kidney disease (CKD) in Asia is expected to increase along with increases of hypertension and diabetes. Most cases are not treated and progress to end-stage renal disease (ESRD) with an increased risk for cardiovascular complications. Renal replacement therapies are so expensive that most ESRD patients die without treatment. Thus, countermeasures against early stages of CKD are urgently needed. Nevertheless, basic information for CKD has not been reported in Vietnam. Methods: We conducted a survey of CKD in 8,505 inhabitants aged >40 years in Vietnam. Subjects with abnormal urinary findings were further examined, including serum creatinine levels. In this study, CKD was defined as <60 ml/min/1.73 m2 of estimated creatinine clearance by the Cockcroft-Gault method. Results: We identified 3.1% of subjects as CKD (stages 3–5) with positive findings in urine test. We also found that elderly hypertension and malnutrition were independent risk factors for CKD in this population. Conclusion: We found a significant number of CKD patients in Vietnam. To avoid a CKD pandemic in Asia including Vietnam, we strongly suggest further analyses of risk factors and prognosis of CKD in these populations, and the development of efficient management systems suitable for Asia.
Short Time to Progression under First-Line Chemotherapy Is a Negative Prognostic Factor for Time to Progression and Residual Survival under Second-Line Chemotherapy in Advanced Pancreatic Cancer
Authors: Herrmann Christina , Abel Ulrich , Stremmel Wolfgang , Jaeger Dirk , Herrmann Thomas
Published: May 2008

Objectives: Second-line chemotherapy is widely used in advanced pancreatic cancer. However, only few data exist concerning the question who might benefit from second-line therapy. We intended to identify prognostic factors for time to second progression (TTP2) and residual survival following second-line chemotherapy of patients with advanced pancreatic cancer. Methods: We performed a retrospective cohort study on 78 patients who started palliative chemotherapy at our department from January 2004 to June 2006 due to advanced adenocarcinoma of the pancreas. 46 patients who progressed following first-line therapy were analyzed. Results: In multivariate analyses, time to first progression (TTP1) <6 months and elevated LDH at the time of diagnosis were shown to be strong and highly significant independent prognostic factors for TTP2 and residual survival. For patients with TTP1 <6 months, prognosis was poor with a median residual survival of 4.4 versus 7.5 months for those with TTP1 ≧6 months. Conclusion: In our cohort of patients with advanced pancreatic cancer treated with second-line chemotherapy, TTP1 <6 months is a strong negative prognostic factor for TTP2 and residual survival.
Nucleolar size and shape is sexually dimorphic in neurons of the lateral magnocellular nucleus of the anterior neostriatum (LMAN) in birds
Authors: Nixdorf-Bergweiler B.E.
Published: May 2008

The lateral magnocellular nucleus of the anterior neostriatum (LMAN) in birds plays an important role in song-earning processes. Recently, it has been shown that structural changes at the cellular level in males are causally related to vocal learning. Whereas males sing, females do not. This sexual difference in behavior is also reflected in sexual differences in the neuronal structure in adult birds, with males having larger neuronal somata than do females. In the present report, the size and shape of the nucleoli were investigated to determine if sexual differences were also present at the nucleolar level. The data demonstrated a strong sexual difference in nucleolar size in both juvenile and adult birds, the cross-sectional area of the nucleoli being significantly larger in males than in females (30% and 50% larger in juvenile and adult birds, respectively). This difference between males and female finches was also reflected by the cross-sectional area of a specific type of nucleolus exhibiting a central light area. In both sexes, nucleoli exhibiting a central light area were significantly larger in juvenile and adult birds than nucleoli that lacked a central light area. The percentage of neurons exhibiting a central light area was higher in adult males than in adult females, but not in juvenile birds. The time course of development of nucleoli exhibiting a central light area in males was very similar to the development of neuronal somata size in LMAN neurons. The larger size of the nucleoli in LMAN neurons in males and the developmental changes in the incidence of nucleoli exhibiting a central light area may be indicative of a high level of ribosome production necessary for song-learning processes to occur.
The rat 5S rRNA bona fide gene repeat maps to chromosome 19q12→qter and the pseudogene repeat maps to 12q12
Authors: Frederiksen S. , Cao H. , Lomholt B. , Levan G. , Hallenberg C.
Published: May 2008

The bona fide 5S rRNA genes in the rat are found in a 1.8-kb tandem repeat and the pseudogenes occur in a 2.5-kb tandem repeat. Three bona fide 5S rRNA genes and one gene variant with one base substitution in the coding region were isolated from the 1.8-kb repeat. Six pseudogenes were isolated from the 2.5-kb repeat. The total number of genes/gene variants/pseudogenes is 700–1200 copies per haploid genome, and the pseudogene repeat contains about 50% more 5S rDNA related sequences compared with the bona fide gene repeat. Various well-defined 5’- and 3’-flanking sequences of the bona fide gene and of the pseudogene were used for in situ hybridization to metaphase chromosomes. The results showed that the bona fide 5S rRNA gene repeat Rn5s maps to chromosome 19ql2 and the pseudogene repeat Rn5sp maps to 12ql2.
Chromosome location of sixteen genes in the common shrew, Sorex araneus L. (Mammalia, Insectivora)
Authors: Matyakhina L.D. , Koroleva I.V. , Malchenko S.N. , Bendixen C. , Cheryaukene O.V. , Pack S.D. , Borodin P.M. , Serov O.L. , Searle J.B.
Published: May 2008

This report extends the genetic map of the common shrew (Sorex αrαneus) by use of a clone panel of shrew-Chinese hamster and shrew-mouse hybrid cells (Pack et al., 1995; Matyakhina et al., 1996). This set of hybrid clones made it possible to assign the shrew genes for isocitrate dehydrogenase 2 (IDH2), inorganic pyrophosphatase (PP), glutamic-pyruvate transaminase (GPT), adenosine kinase (ADK), glucuronidase 2 (GUSB) and acid phosphatase 2 (ACP2) to chromosome ik, the genes for adenylate kinases 1 and 3 (AK1 and AK3) to chromosome af; the genes for glutamate-oxaloacetate transaminase 2 (GOT2), peptidase D (PEPD) and growth hormone (GH) to chromosome hn; the gene for phosphoglucomutase 2 (PGM2) to chromosome go, the gene for enolase 1 (ENOl) to chromosome jl, the gene for ornithine carbamoyl-transferase (OTC) to chromosome de, the gene for aminoacylase 1 (ACY1) to arm m (chromosome mp), the gene for glutamate-oxaloacetate transaminase 1 (GOT1) to arm q (chromosome qr). Thus, the genetic map of the common shrew now contains 33 genes and it is possible to compare the syntenic associations with other species.
Segmental homology among cattle (Bos taurus), Indian muntjac (Muntiacus muntjak vaginalis), and Chinese muntjac (M. reevesi) karyotypes
Authors: Frönicke L. , Chowdhary B.P. , Scherthan H.
Published: May 2008

In an attempt to examine homologies between Indian and Chinese muntjac karyotypes at a subchromosomal level, five bovine cosmids were comparatively mapped by heterologous fluorescence in situ hybridization (FISH). In the Indian muntjac (2n = 6) all cosmids mapped to chromosome 1, whereas in the Chinese muntjac (2n = 46) two cosmids mapped to chromosome 3 and one cosmid each mapped to chromosomes 1, 7, and 17. These markers have maintained their intrachromosomal position relative to a centromere/telomere axis in cattle and in Chinese and Indian muntjac chromosomal arms. Our results corroborate the tandem-fusion hypothesis for muntjac karyotypic evolution and establish orientational homology between the involved Chinese muntjac chromosomes and the discrete segments on Indian muntjac chromosome 1. Furthermore, our data disclose regional homologies between cattle and muntjac genomes and demonstrate the validity of intergeneric cosmid-FISH for investigations on karyotype evolution.
A panel of radiation hybrids and YAC clones specific for human chromosome 5
Authors: Marzella R. , Viggiano L. , Ricco AS. , Tanzariello A. , Fratello A. , Archidiacono N. , Rocchi M.
Published: May 2008

We report the characterization, by reverse fluorescence in situ hybridization (FISH), of 59 hybrids retaining fragments of human chromosome 5. Most of these hybrids are radiation hybrids generated by gamma irradiating, at low dosage, a monochromosomal hybrid retaining chromosome 5 as its only human contribution. The partial chromosome paints generated from these hybrids will make powerful tools for cytogenetic investigations, especially on the cytogenetic evolution of primates, and examples are reported. The molecular characterization of these hybrids was refined using 74 sequence-tagged sites (STSs), which allowed the physical dissection of chromosome 5 into 71 distinct regions with an average length of 2.7 Mb. The panel, therefore, is also suitable for high-precision subregional mapping of new genes or sequences located on chromosome 5. As an additional resource for cytogenetic studies involving chromosome 5, we report the characterization, by FISH, of 73 YACs from CEPH. The vast majority of these YACs are recognized by at least one of the STSs used for hybrid characterization, thus enabling the integrated use of YACs and partial chromosome paints derived from the hybrids.
Development of diagnostic tools for the analysis of 5p deletions using interphase FISH
Authors: Gersh M. , Grady D. , Rojas K. , Lovett M. , Moyzis R. , Overhauser J.
Published: May 2008

Cri-du-chat syndrome is associated with a deletion of the short arm of chromosome 5. Through the phenotypic and molecular analyses of individuals with a subset of the features associated with the syndrome, the genes involved in the syndrome have been mapped to two distinct critical regions. Deletion of a critical region in 5p15.2 results in the distinct facial features associated with the syndrome as well as the severe mental and developmental delay, while a deletion of 5pl 5.3 is associated only with the characteristic cat-like cry, the key diagnostic feature of the syndrome. Therefore, subtle differences in the extent of the 5p deletion can have a profound affect on the prognosis of the patient. In order to more easily differentiate between deletions that lead to the cri-du-chat syndrome phenotype and deletions that lead only to the isolated cat-like cry, we have constructed YAC contigs that span both critical regions. The YAC clones have been used to isolate cosmids mapping to each critical region and cosmids that lie just within the two critical region boundaries have been identified. We report here on the use of these cosmids as probes for fluorescent in situ hybridization experiments on interphase nuclei as a means of more accurately differentiating between small 5p deletions that coincide with a complete cri-du-chat syndrome phenotype and the severe mental and developmental delay that is associated with it and deletions that only delete the distal critical region that coincide with the isolated cat-like cry and a much improved prognosis.
Comparative genomic hybridization analysis of Y79 and FISH mapping indicate the amplified human mitochondrial ATP synthase α-subunit gene (ATP5A) maps to chromosome 18q12→q21
Authors: Godbout R. , Pandita A. , Beatty B. , Bie W. , Squire J.A.
Published: May 2008

The four mitochondrial ATP synthase α-subunit (ATP5A) genes map to chromosomes 2, 9, 16, and 18. In this study we have refined the localization of two of these genes by fluorescence in situ hybridization (FISH) to metaphase spreads, and further characterised the involvement of ATP5A in the amplification process in the retinoblastoma cell line Y79. Comparative genomic hybridization (CGH) analysis of Y79 indicated that gene amplification was present on both the short arm of chromosome 2 and the long arm of chromosome 18. FISH indicated that the functional ATP5A gene mapped to 18q12→q21 the same band location identified by CGH analysis of Y79. An ATP5A pseudogene (ATP5AP1) maps to 9p12. Gains in chromosomal material at 18q12→q21 likely involve hybridization to amplified copies of the ATP5A gene while gains at 2p24 represent hybridization to the MYCN and DDX1 genes, also amplified in Y79.
Comparative genomic hybridization analysis of Wilms tumors
Authors: Steenman M. , Redeker B. , de Meulemeester M. , Wiesmeijer K. , Voûte P.A. , Westerveld A. , Slater R. , Mannens M.
Published: May 2008

In this study we have applied the technique of comparative genomic hybridization (CGH) to a large series of sporadic Wilms tumors, including six samples of the associated nephroblastomatosis. The data obtained were compared with the findings of molecular studies carried out on the same material. The aims of the study were (1) to characterize the range of genetic variation in sporadic Wilms tumor and nephroblastomatosis, (2) to determine whether changes could be found that have not been detected by commonly used techniques, and (3) to compare the sensitivity of CGH with that of conventional molecular analysis. The chromosomes that showed gains and losses by CGH were similar to those previously found in molecular and cytogenetic studies, however loss of 4q was a new event identified in 2 out of 46 tumors. We did not detect amplified genetic material. Comparison of the data from the nephroblastomatosis and tumor samples from the same patient showed that loss of 7p may be associated with malignant transformation, and that losses in 1p, 11p, 4q and gains in 1q and 12q can be early events; whilst loss in 9p and gain of 8, 10q and 18 are possible secondary changes in tumor development. The combined CGH and molecular techniques used demonstrated involvement of two specific 1p regions in the etiology of Wilms tumor.
Multiple, polymorphic copies of SRY in both males and females of the vole Microtus cabrerae
Authors: Bullejos M. , Sánchez A. , Burgos M. , Hera C. , Jiménez R. , Díaz de la Guardia R.
Published: May 2008

In mammals, sex determination is controlled by the Y-linked gene SRY. Although SRY is male-specific in most eutherian and marsupial species, with a single copy on the Y chromosome, several rodent species have multiple Y-linked copies of SRY, and two mole-vole species of the genus Ellobius determine sex without the Y chromosome or the SRY gene. We searched for homologs of SR Y in three vole species of the genus Microtus and concluded that this gene is not male-specific in M. cαbrerae, as it is present in multiple, polymorphic copies in both males and females. In contrast, SRY is male-specific in the related species M. agrestis and M. nivalis. Up to 15 different partial sequences of the SRY gene were found in M. cαbrerαe. Southern blots suggest that most of the extra copies of SR Fare X-linked. One of the copies observed only in males has a sequence identical to that of the SRY gene in M. agrestis and may represent a functional copy of the gene in this species. The rest are probably nonfunctional pseudogenes.
Chromosomal mapping of the gene encoding serotonin N-acetyltransferase to rat chromosome 10q32.3 and mouse Chromosome 11E2
Authors: Yoshimura T. , Nagabukuro A. , Matsuda Y. , Suzuki T. , Kuroiwa A. , ligo M. , Namikawa T. , Ebihara S.
Published: May 2008

Pineal melatonin is produced during the night. Its nocturnal increase regulates circadian rhythms and the photo-periodic reproductive response. Serotonin is acetylated to N-acetylserotonin by serotonin N-acetyltransferase (SNAT) and then methylated to form melatonin by hydroxyindole-O-methyltransferase (HIOMT). The rhythmicity of melatonm synthesis is regulated by the rhythmic activity of SNAT. Most laboratory mice do not have melatonin because of a genetic defect in the activity of SNAT and/or HIOMT. In a previous study using a recombinant inbred strain, we have found that the locus controlling pineal SNAT activity (Nat4) is located on mouse Chromosome 11. Recently, SNAT has been cloned in the rat. In the present study, the gene encoding SNAT was localized, using a rat cDNA fragment, on rat and mouse chromosomes by direct R-banding fluorescence in situ hybridization (FISH). In addition, using molecular linkage analysis with interspecific back-cross mice, a gene encoding SNAT was mapped on a mouse chromosome. The gene encoding SNAT was localized to rat chromosome 10q32.3 and mouse Chromosome 11E2 by FISH. The molecular linkage analysis demonstrated that the gene encoding SNAT maps 1.5 cM distal to DUMit11. The data suggest that Nat4 encodes SNAT. These chromosomal locations are in a region of conserved linkage homology between the two species.
Cytogenetics of collared lemmings (Dicrostonyx groenlandicus) I. Meiotic behavior and evolution of the neo-XY sex-chromosome system
Authors: Berend S.A. , Hale D.W. , Engstrom M.D. , Greenbaum I.F.
Published: May 2008

Electron-microscopic analysis of surface-spread synaptonemal complexes at pachynema and light-microscopic analysis of chromosomal configurations at diakinesis/metaphase I corroborate the hypothesized neo-XY derivation of the sex chromosomes of Dicrostonyx groenlandicus. Although an intact neo-XY pairing configuration was observed in a relatively small percentage of the pachytene cells in each individual, the high incidence of neo-XY bivalents at diakinesis/metaphase I suggests that the other observed pachytene configurations were artifacts of the physical stresses of the surface-spreading procedure. The very low frequency (0.6 %) of univalent neo-X and neo-Y chromosomes at diakinesis and metaphase I is attributable to consistent synapsis and recombination between their homologous autosomally derived segments. The resultant stability of the sex bivalent through metaphase I may have increased the efficacy of sex-chromosome segregation, and thereby played a mechanistic role in the evolutionary incorporation of the neo-XY sex-chromosome constitution in D. groenlαndicus.
Rare Cases of Primary Pleural Hodgkin and Non-Hodgkin Lymphomas
Authors: Steiropoulos Paschalis , Kouliatsis George , Karpathiou Georgia , Popidou Maria , Froudarakis Marios E.
Published: May 2008

Primary pleural lymphoma is rare. It occurs in only 7% of lymphoma cases. We report herein two cases of primary pleural Hodgkin and non-Hodgkin follicular lymphomas diagnosed by thoracoscopy under local anesthesia. Both patients presented initially with dyspnea revealing pleural effusions. The pleural findings during thoracoscopy differed in the two cases and selective pleural biopsies under optical forceps led to the diagnosis of lymphoma. To date, primary pleural Hodgkin and non-Hodgkin follicular lymphomas have not been reported.
Tribology's contribution to archaeology
Authors: Gluchy A. , Vargiolu R. , Mordant C. , Zahouani H.
Published: May 2008

Nowadays, archaeology is a multidisciplinary science, aware of the possibilities which advanced technologies can bring about. Thus tribology, the science of wear and friction, has been for some time one of the analysing techniques leading to a better knowledge of our past. It studies the mechanisms of wear, abrasion and friction which took place during the manufacturing or the use of an object. Recently, two hoards of bronze objects, dating from the middle phase of the Final Bronze Age (1100–900 BC), were discovered on the site of les Feuilly in Saint-Priest (Rhône, France). These bronzes which reached us are the last markers of the techniques of former craftsmen: their surfaces reveal many traces, which are the memory of their manufacturing skills and their ‘social life’. The archaeological and tribological study was conceived to raise questions about gestures and processes used particularly for the decoration of bronze objects, in order to have a better knowledge of the crafstman's know-how. We could determine that decorative patterns of the bracelet 375 were created after the casting process, by chasing. The tools used were thus chasing tools, probably made of bronze. We had also the possibilities to reconstitute part of the kinetics of the bracelet decoration.
EBV-positive immunodeficiency lymphoma after alemtuzumab-CHOP therapy for peripheral T-cell lymphoma
Authors: Kluin-Nelemans Hanneke C. , Coenen Jules L. , Boers James E. , van Imhoff Gustaaf W. , Rosati Stefano
Published: May 2008

Chemotherapy with alemtuzumab and the combination of cyclophosphamide, adriamycin, oncovin, and prednisone (CHOP) has become experimental trial therapy for aggressive T-cell lymphoma. Several multicenter phase 3 trials will incorporate this scheme. As part of an ongoing phase 2 trial in which we recently treated 20 patients with 8 cycles of CHOP every 2 weeks with 3 additional doses of 30 mg alemtuzumab per cycle, we observed the development of Epstein-Barr virus (EBV)-positive lymphoproliferative disease, after completion of the immunochemotherapy in 3 patients with peripheral T-cell lymphoma. Because the occurrence of EBV-positive lymphoproliferative disease is rare after alemtuzumab monotherapy, such as is given for chronic lymphocytic leukemia, we think that early reporting of this potential side effect is warranted. It may be caused by intrinsic T-cell defects in patients with T-cell lymphoma, or by the combination of alemtuzumab with CHOP chemotherapy.