bluuebunny/crossref_metadata_2025 huggingface dataset:
Tamoxifen Stimulates Cancellous Bone Formation in Long Bones of Female Mice
Authors: Perry M. J. , Gujra S. , Whitworth T. , Tobias J. H.
Published: December 2004

Selective estrogen receptor modulators (SERMs) have been developed as a means of targeting estrogen’s protective effect on the skeleton in the treatment of postmenopausal osteoporosis. Although it is well established that SERMs such as tamoxifen inhibit bone resorption in a similar manner to estrogen, whether this agent shares estrogen’s stimulatory action on bone formation is currently unclear. To address this question, we compared the effect of treatment for 28 d with 17β-estradiol (E2; 0.1, 1.0 mg/kg·d) and tamoxifen (0.1, 1.0, or 10 mg/kg·d) on cancellous bone formation at the proximal tibial metaphysis of intact female mice. E2 stimulated the formation of new cancellous bone throughout the metaphysis. A similar response was observed after administration of tamoxifen, the magnitude of which was approximately 50% of that seen after E2. As expected, E2 was found to suppress longitudinal bone growth, but in contrast, this parameter was stimulated by tamoxifen. We conclude that tamoxifen acts as an agonist with respect to estrogen’s stimulatory action on bone formation but as an antagonist in terms of estrogen’s inhibition of longitudinal growth, suggesting that the protective effect of SERMs on the skeleton is partly mediated by stimulation of osteoblast activity.
Effects of Atorvastatin on the Clearance of Triglyceride-Rich Lipoproteins in Familial Combined Hyperlipidemia
Authors: Castro Cabezas M. , Verseyden C. , Meijssen S. , Jansen H. , Erkelens D. W.
Published: December 2004

Familial combined hyperlipidemia (FCHL) patients have an impaired catabolism of postprandial triglyceride (TG)-rich lipoproteins (TRLs). We investigated whether atorvastatin corrects the delayed clearance of large TRLs in FCHL by evaluating the acute clearance of Intralipid (10%) and TRLs after oral fat-loading tests. Sixteen matched controls were included. Atorvastatin reduced fasting plasma TG (from 3.6 ± 0.4 to 2.5 ± 0.3 mm; mean ± sem) without major effects on fasting apolipoprotein B48 (apoB48) and apoB100 in large TRLs. Atorvastatin significantly reduced fasting intermediate density lipoprotein (Svedberg flotation, 12–20)-apoB100 concentrations. After Intralipid, TG in plasma and TRL showed similar kinetics in FCHL before and after atorvastatin treatment, although compared with controls, the clearance of large TRLs was only significantly slower in untreated FCHL, suggesting an improvement by atorvastatin. Investigated with oral fat-loading tests, the clearance of very low density lipoprotein (Sf20–60)-apoB100 improved by 24%, without major changes in the other fractions. The most striking effects of atorvastatin on postprandial lipemia in FCHL were on hepatic TRL, without major improvements on intestinal TRLs. Fasting plasma TG should be reduced more aggressively in FCHL to overcome the lipolytic disturbance causing delayed clearance of postprandial TRLs.
Preeclampsia and Future Cardiovascular Disease: Potential Role of Altered Angiogenesis and Insulin Resistance
Authors: Wolf Myles , Hubel Carl A. , Lam Chun , Sampson Marybeth , Ecker Jeffrey L. , Ness Roberta B. , Rajakumar Augustine , Daftary Ashi , Shakir Alia S. M. , Seely Ellen W. , Roberts James M. , Sukhatme Vikas P. , Karumanchi S. Ananth , Thadhani Ravi
Published: December 2004

Altered angiogenesis and insulin resistance are associated with preeclampsia and cardiovascular disease (CVD), and women with preeclampsia appear to be at increased risk of future CVD. We hypothesized that these factors are detectable in asymptomatic postpartum women with a history of preeclampsia and may represent pathophysiological mechanisms bridging preeclampsia and future CVD. We measured fasting insulin, glucose, vascular endothelial growth factor, and its circulating inhibitor, soluble fms-like tyrosine kinase (sFlt-1) in 29 normotensive women with a history of preeclampsia and 32 women with prior normotensive pregnancies at 18.0 ± 9.7 months postpartum. The homeostasis model of insulin resistance (HOMAIR) [(insulin [microunits per milliliter] × glucose [millimoles per liter])/22.5] was calculated. Compared with women with normal pregnancies, women with prior preeclampsia had significantly increased levels of sFlt-1 (41.6 ± 6.7 vs. 30.4 ± 10.2; P < 0.01) and median HOMAIR (2.8 vs. 1.9; P = 0.04). Membership in the upper quartile of either sFlt-1 or HOMAIR was associated with prior preeclampsia (odds ratio 5.7; 95% confidence interval 1.7, 20.0; P < 0.01), and all five women in the upper quartiles of both sFlt-1 and HOMAIR had a history of preeclampsia. Women with a history of preeclampsia demonstrate altered expression of angiogenesis-related proteins and increased HOMAIR more than 1 yr postpartum. These factors may contribute to their risk of future CVD.
X-Chromosome Inactivation Patterns and Androgen Receptor Functionality Influence Phenotype and Social Characteristics as Well as Pharmacogenetics of Testosterone Therapy in Klinefelter Patients
Authors: Zitzmann Michael , Depenbusch Marion , Gromoll Jörg , Nieschlag Eberhard
Published: December 2004

Klinefelter syndrome is characterized by a vast range of phenotypes related to androgen effects. Testosterone (T) acts via the X-linked androgen receptor gene carrying the CAG repeat (CAGn) polymorphism, the length of which is inversely associated with androgen action and might account for the marked variation in phenotypes. In 77 newly diagnosed and untreated Klinefelter patients with a 47,XXY karyotype we assessed phenotype and social traits in relation to X-weighted biallelic CAGn length using X-chromosome inactivation analysis after digestion of leukocyte DNA with methylation-sensitive HpaII. Forty-eight men were hypogonadal and received T substitution therapy; in these, pharmacogenetic effects were investigated. The shorter CAGn allele was preferentially inactive. CAGn length was positively associated with body height. Bone density and the relation of arm span to body height were inversely related to CAGn length. The presence of long CAGn was predictive for gynecomastia and smaller testes, whereas short CAGn were associated with a stable partnership and professions requiring higher standards of education also when corrected for family background. There was a trend for men with longer CAGn to be diagnosed earlier in life. Under T substitution, men with shorter CAGn exhibited a more profound suppression of LH levels, augmented prostate growth, and higher hemoglobin concentrations. A significant genotype-phenotype association exists in Klinefelter patients: androgen effects on appearance and social characteristics are modulated by the androgen receptor CAGn polymorphism. The effects of T substitution are pharmacogenetically modified. This finding is magnified by preferential inactivation of the more functional short CAGn allele.
Subcortical White Matter Metabolic Changes Remote from Focal Hemorrhagic Lesions Suggest Diffuse Injury after Human Traumatic Brain Injury
Authors: Wu Hsiao-Ming , Huang Sung-Cheng , Hattori Naoya , Glenn Thomas C. , Vespa Paul M. , Hovda David A. , Bergsneider Marvin
Published: December 2004

OBJECTIVE:

We used positron emission tomographic studies to prospectively examine the relationship between glucose and oxidative metabolism in the subcortical white matter (WM) acutely after traumatic brain injury (TBI). The objective was to determine the nature, extent, and degree of metabolic abnormalities in subcortical brain regions remote from hemorrhagic lesions.

METHODS:

Sixteen normal volunteers and 10 TBI patients (Glasgow Coma Scale score, 4–10; age, 17–64 yr; 6 with focal and 4 with diffuse injury) were studied. Each subject underwent dynamic positron emission tomographic studies using [15O]CO, 15O2, [15O]H2O, and fluorodeoxyglucose plus a magnetic resonance imaging scan acutely after TBI. Parametric images of the metabolic rate of oxygen and metabolic rate of glucose were generated, and a molar oxygen-to-glucose utilization ratio was calculated. Data from gray matter and WM remote from hemorrhagic lesions, plus whole brain, were analyzed.

RESULTS:

There was a significant reduction in the subcortical WM oxygen-to-glucose utilization ratio after TBI compared with normal values (3.99 ± 0.77 versus 5.37 ± 1.00; P < 0.01), whereas the mean cortical gray matter and whole-brain values remained unchanged. WM metabolic changes, which were diffuse throughout the hemispheres, were characterized by a reduction in the metabolic rate of oxygen without a concomitant drop in the metabolic rate of glucose.

CONCLUSION:

The extent and degree of subcortical WM metabolic abnormalities after moderate and severe TBI suggest that diffuse WM injury is a general phenomenon after such injuries. This pervasive finding may indicate that the concept of focal traumatic injury, although valid from a computed tomographic imaging standpoint, may be misleading when considering metabolic derangements associated with TBI.
Radiotherapeutic Factors in the Management of Cervical-basal Chordomas and Chondrosarcomas
Authors: Noël Georges , Feuvret Loïc , Ferrand Régis , Boisserie Gilbert , Mazeron Jean-Jacques , Habrand Jean-Louis
Published: December 2004

OBJECTIVE:

To define prognostic factors for local control and survival in 90 consecutive patients treated by fractionated photon and proton radiation for chordoma or chondrosarcoma of the cranial base and upper cervical spine.

METHODS:

Between December 1995 and December 2000, 90 patients (median age, 51.3 yr; range, 10–85 yr; male/female ratio, 3:2) were treated by a combination of high-energy photons and protons. Sixty-four patients had a chordoma, and 26 had a chondrosarcoma. The proton component was delivered by the 201-MeV proton beam of the Centre de Protonthérapie d'Orsay. The median total dose delivered to the gross tumor volume (GTV) was 67 cobalt Gray equivalents (range, 22–70 cobalt Gray equivalents).

RESULTS:

With a median follow-up of 34 months (range, 3–74 mo), treatment of 25 tumors failed locally. The 3-year local control rates were 69.2% (±6.0%) and 91.6% (±8.4%) for chordomas and chondrosarcomas, respectively. According to multivariate analysis, a small tumor volume excluded from the 95% isodose line (P = 0.032; relative risk [RR], 0.098; 95% confidence interval [CI], 0.01–0.81) and a controlled tumor (P = 0.049; RR, 0.19; 95% CI, 0.04–0.99) were independent favorable prognostic factors for overall survival. On multivariate analysis, a high minimum dose (P = 0.02; RR, 2.8; 95% CI, 1.2–6.6), a high tumor control probability (P = 0.02; RR, 3.8; 95% CI, 1.2–12.5), a high dose delivered to 95% of the GTV (P = 0.03; RR, 3.4; 95% CI, 1.15–10.2), a high GTV encompassed by the 90% isodose line (P = 0.01; RR, 3.29; 95% CI, 1.29–8.44), and a small GTV excluded from the 90% isodose line (P = 0.036; RR, 0.4; 95% CI, 0.1–0.9) were independent favorable prognostic factors for local control.

CONCLUSION:

In chordomas and chondrosarcomas of the cranial base and cervical spine treated by surgical resection and then by high-dose photon and proton irradiation, local control is mainly dependent on the quality of radiation, especially dose uniformity within the GTV. Special attention must be paid to minimize underdosed areas because of the close proximity of critical structures and to redefine and possibly escalate dose constraints to tumor targets in future studies in view of the low toxicity observed to date.
Spinal en Plaque Meningiomas: A Contemporary Experience
Authors: Caroli Emanuela , Acqui Michele , Roperto Raffaelino , Ferrante Luigi , D'Andrea Giancarlo
Published: December 2004

OBJECTIVE:

Spinal en plaque meningiomas are rare and challenging lesions because of their tendency to induce spinal arachnoiditis. The surgical treatment of this type of meningioma is more complex than that of classic meningioma.

METHODS:

We report seven cases of spinal en plaque meningiomas and review all the cases reported in the literature accessible to us by a MEDLINE search.

RESULTS:

All patients underwent microsurgery. Complete tumor removal was achieved in three patients. Subtotal removal was performed in four patients. A permanent neurological worsening was observed in one patient.

CONCLUSION:

Spinal meningiomas en plaque bear a prognosis poorer than that of classic meningiomas with regard to the possibility of a definitive surgical cure because recurrence or postoperative arachnoiditis occurs frequently. Total surgical removal should be attempted only when a clear plane of cleavage between tumor and arachnoid exists.
Evaluating the Effect of Decompression Surgery on Cerebrospinal Fluid Flow and Intracranial Compliance in Patients with Chiari Malformation with Magnetic Resonance Imaging Flow Studies
Authors: Sivaramakrishnan Anusha , Alperin Noam , Surapaneni Sushma , Lichtor Terry
Published: December 2004

OBJECTIVE:

To quantify the effect of decompression surgery on craniocervical junction hydrodynamics and on global intracranial compliance (ICC) in patients with Chiari I malformation by use of magnetic resonance measurements of cerebrospinal fluid and blood flow. Studying the effect of decompression surgery may improve our understanding of the pathophysiological characteristics of Chiari I malformation and aid in identifying patients who will benefit from the procedure.

METHODS:

Twelve patients were studied with a 1.5-T magnetic resonance imaging scanner before and after decompression surgery. Cine phase contrast magnetic resonance images were used to quantify maximum cord displacement, maximum systolic cerebrospinal fluid velocity and volumetric flow rate, and overall ICC. ICC was derived by use of a previously reported method that measures small changes in intracranial volume and pressure that occur naturally with each cardiac cycle.

RESULTS:

After surgery, changes were documented both in the local hydrodynamic parameters and in ICC. However, only the change in ICC, an average increase of more than 60%, was statistically significant. Increased ICC, which was associated with improved outcome, was measured in 10 of the 12 patients, no significant change was documented in 1 patient, and decreased ICC was measured in 1 patient whose symptoms persisted after surgery.

CONCLUSION:

An increase in the overall compliance of the intracranial compartment is the most significant and consistent change measured after decompression surgery. Changes in cord displacement, cerebrospinal fluid velocities, and flow in the craniospinal junction were less consistent and less affected by the operation. Thus, ICC may play an important role in the outcome of decompression surgery related to improving symptoms and restoring normal neurological hydrodynamics in patients with Chiari I malformations.
A Call to Define Stereotactic Radiosurgery
Authors: Pollock Bruce E. , Lunsford L Dade
Published: December 2004

STEREOTACTIC RADIOSURGERY IS the single-session, precise delivery of a therapeutically effective radiation dose to an imaging-defined target. Conceived and developed during the past 5 decades, stereotactic radiosurgery has involved significant advances, which have improved patient outcomes and made it a critical component of modern neurosurgical practice and training. In this article, a short history of stereotactic surgery and radiosurgery are presented, and radiosurgery is contrasted to radiation therapy. Adherence to accepted, descriptive terms in defining stereotactic radiosurgery and radiation therapy permits a clear distinction among the results of the different radiation delivery techniques for patients, physicians, and other interested parties.
Toward an Expanded View of Radiosurgery
Authors: Adler John R. , Colombo Federico , Heilbrun M Peter , Winston Ken
Published: December 2004

RADIOSURGERY AND RADIOTHERAPY were originally distinguished on the basis of the manner in which they protected normal tissues from radiation injury. Radiosurgery does so by precise targeting of cross-fired radiation beams to abnormal tissue, with abrupt falloff of radiation doses to surrounding normal tissue. Radiotherapy was historically less concerned with targeting accuracy and anatomic precision; normal tissues were protected by dividing doses into multiple fractions separated by time to allow recovery of normal tissues. By this means, radiotherapy applied radiobiological principles to disrupt dividing cells selectively. Despite the development of computer-based, image-guided frameless technology that eliminates the necessity to perform radiosurgery in a single session, there are some who still insist that radiosurgery be distinguished from radiotherapy on the basis of whether treatment is delivered in a single session. Here, we propose that this definition of radiosurgery is needlessly restrictive and that staging or hypofractionation of radiosurgical treatment permits the limited application of radiobiological principles of radiotherapy to improve radiosurgical treatment. We therefore define radiosurgery as a procedure that involves the active participation of a surgeon and in which spatially accurate and highly conformal doses of radiation are targeted at well-defined structures with an ablative intent.
Multiple Spinal Cavernous Malformations with Atypical Phenotype after Prior Irradiation: Case Report
Authors: Jabbour Pascal , Gault Judith , Murk Steven E. , Awad Issam A.
Published: December 2004

OBJECTIVE AND IMPORTANCE:

This is the first reported case of histologically proven multiple spinal cavernous malformations (CMs) associated with previous irradiation. There are only two cases reported in the literature of solitary spinal CM after irradiation. In addition, the lesions in our patient had an atypical magnetic resonance imaging appearance mimicking intraspinal drop metastasis.

CLINICAL PRESENTATION:

A 33-year-old man had an incidental finding of multiple enhancing intraspinal lesions as revealed by magnetic resonance imaging during staging tests for hepatocellular carcinoma. He had a history of Wilms' tumor at a young age with irradiation to the abdomen and pelvis. His family history included a paternal cousin with multiple cerebral CMs. The diagnosis of spinal drop metastasis was made, and further intervention was undertaken for confirmation.

INTERVENTION:

The patient underwent a lumbar laminectomy with durotomy and excision of two of the lesions. Macroscopic analysis revealed mulberry-like appearance with nerve root involvement, and pathological analysis confirmed the diagnosis of CM. Genetic testing of the patient and his affected cousin was negative for the CCM1 gene.

CONCLUSION:

The occurrence of multiple spinal lesions in the context of known neoplasia indicates a diagnosis of metastasis. Spinal CMs were not suspected preoperatively because of the atypical appearance revealed by magnetic resonance imaging scans, with uniform contrast enhancement and absence of hemosiderin rim. This case report is discussed relative to previous literature regarding radiation-induced CMs and other known causes of the disease.
Spermatogenesis from epiblast and primordial germ cells following transplantation into postnatal mouse testis
Authors: Chuma Shinichiro , Kanatsu-Shinohara Mito , Inoue Kimiko , Ogonuki Narumi , Miki Hiromi , Toyokuni Shinya , Hosokawa Mihoko , Nakatsuji Norio , Ogura Atsuo , Shinohara Takashi
Published: December 2004

Primordial germ cells (PGCs) are derived from a population of pluripotent epiblast cells in mice. However, little is known about when and how PGCs acquire the capacity to differentiate into functional germ cells, while keeping the potential to derive pluripotent embryonic germ cells and teratocarcinomas. In this investigation, we show that epiblast cells and PGCs can establish colonies of spermatogenesis after transfer into postnatal seminiferous tubules of surrogate infertile mice. Furthermore, we obtained normal fertile offspring by microinsemination using spermatozoa or spermatids derived from PGCs harvested from fetuses as early as 8.5 days post coitum. Thus, fetal male germ cell development is remarkably flexible, and the maturation process, from epiblast cells through PGCs to postnatal spermatogonia, can occur in the postnatal testicular environment. Primordial germ cell transplantation techniques will also provide a novel tool to assess the developmental potential of PGCs, such as those manipulated in vitro or recovered from embryos harboring lethal mutations.
Different thresholds of fibroblast growth factors pattern the ventral foregut into liver and lung
Authors: Serls Amanda E. , Doherty Shawna , Parvatiyar Pankhuri , Wells James M. , Deutsch Gail H.
Published: December 2004

Cell fate and morphogenesis within the embryo is dependent upon secreted molecules that transduce signals between neighboring tissues. Reciprocal mesenchymal-epithelial interactions have proven essential during branching morphogenesis and cell differentiation within the lung; however, the interactions that result in lung specification from the foregut endoderm,prior to lung bud formation, are poorly understood. In this study, we investigate the tissue requirements and signals necessary for specification of a pulmonary cell fate using embryo tissue explants. We show that NKX2.1, an early transcription factor crucial for lung development, is expressed in the ventral foregut endoderm shortly after albumin and Pdx1, early markers of the liver and pancreas lineages, respectively. Similar to hepatic specification,direct contact of cardiac mesoderm with ventral endoderm is required to induce in vitro expression of NKX2.1 and downstream lung target genes including surfactant protein C and Clara cell secretory protein. In the absence of cardiac mesoderm, ventral foregut endoderm explants respond to exogenous fibroblast growth factor (FGF) 1 and FGF2 in a dose-dependent manner, with lower concentrations activating liver specific genes and higher concentrations activating lung specific genes. This signaling appears to be instructive, as the prospective dorsal midgut endoderm, which predominantly gives rise to the intestinal tract, is competent to respond to FGFs by inducing NKX2.1. Furthermore, the temporal expression and selective inhibition of FGF receptors 1 and 4 present within the endoderm implies that signaling through FGFR4 is involved in specifying lung versus liver. Together, the findings suggest that a concentration threshold of FGFs emanating from the cardiac mesoderm are involved in patterning the foregut endoderm.
A GPI-linked carbonic anhydrase expressed in the larval mosquito midgut
Authors: Seron Terri J. , Hill Jennifer , Linser Paul J.
Published: December 2004

We have previously described the first cloning and partial characterization of carbonic anhydrase from larval Aedes aegypti mosquitoes. Larval mosquitoes utilize an alkaline digestive environment in the lumen of their anterior midgut, and we have also demonstrated a critical link between alkalization of the gut and carbonic anhydrase(s). In this report we further examine the nature of the previously described carbonic anhydrase and test the hypothesis that its pattern of expression is consistent with a role in gut alkalization. Additionally we take advantage of the recently published genome of the mosquito Anopheles gambiae to assess the complexity of the carbonic anhydrase gene family in these insects. We report here that the previously described carbonic anhydrase from Aedes aegypti is similar to mammalian CA IV in that it is a GPI-linked peripheral membrane protein. In situ hybridization analyses identify multiple locations of carbonic anhydrase expression in the larval mosquito. An antibody prepared against a peptide sequence specific to the Aedes aegypti GPI-linked carbonic anhydrase labels plasma membranes of a number of cell types including neuronal cells and muscles. A previously undescribed subset of gut muscles is specifically identified by carbonic anhydrase immunohistochemistry. Bioinformatic analyses using the Ensembl automatic analysis pipeline show that there are at least 14 carbonic anhydrase genes in the Anopheles gambiae genome, including a homologue to the GPI-linked gene product described herein. Therefore, as in mammals which similarly possess numerous carbonic anhydrase genes, insects require a large family of these genes to handle the complex metabolic pathways influenced by carbonic anhydrases and their substrates.
Kinetics and rhythm of body contractions in the spongeTethya wilhelma(Porifera: Demospongiae)
Authors: Nickel Michael
Published: December 2004

Sponges of the species Tethya wilhelma display rhythmic body contractions, which were analyzed by digital timelapse imaging and semi-automated image analysis. For the first time, differential, quantitative data on sponge behaviour could be obtained. The sponges are able to reduce their body volume by up to 73.3% during regular contractions. Each contraction cycle follows a characteristic pattern of four phases, permitting analysis of the kinetics of contraction and expansion. Long-term observations (for >7 days) reveal that the sponge contractions display a day-night periodicity in which contraction cycles are significantly longer during the dark hours. The contractions seem to be mediated by the pinacoderm; they are triggered locally and spread over the sponge surface at 12.5 μm s-1. If two individuals of a clone are fused, the individual contraction rhythm of both sponges persists for several days, until a single new individual sponge is formed with a synchronized rhythm. The reported results and techniques establish T. wilhelma as a model organism for research on the development of aneural signal transduction and integration during early Metazoan evolution.
Ammonia excretion in aquatic and terrestrial crabs
Authors: Weihrauch Dirk , Morris Steve , Towle David W.
Published: December 2004

The excretory transport of toxic ammonia across epithelia is not fully understood. This review presents data combined with models of ammonia excretion derived from studies on decapod crabs, with a view to providing new impetus to investigation of this essential issue. The majority of crabs preserve ammonotely regardless of their habitat, which varies from extreme hypersaline to freshwater aquatic environments, and ranges from transient air exposure to obligate air breathing. Important components in the excretory process are the Na+/K+(NH4+)-ATPase and other membrane-bound transport proteins identified in many species, an exocytotic ammonia excretion mechanism thought to function in gills of aquatic crabs such as Carcinus maenas, and gaseous ammonia release found in terrestrial crabs, such as Geograpsus grayi and Ocypode quadrata. In addition, this review presents evidence for a crustacean Rhesus-like protein that shows high homology to the human Rhesus-like ammonia transporter both in its amino acid sequence and in its predicted secondary structure.
Cold-stable eye lens crystallins of the Antarctic nototheniid toothfishDissostichus mawsoniNorman
Authors: Kiss Andor J. , Mirarefi Amir Y. , Ramakrishnan Subramanian , Zukoski Charles F. , DeVries Arthur L. , Cheng Chi-Hing C.
Published: December 2004

The eye lenses of the Antarctic nototheniid fishes that inhabit the perennially freezing Antarctic seawater are transparent at –2°C,whereas the cold-sensitive mammalian and tropical fish lenses display cold-induced cataract at 20°C and 7°C, respectively. No cold-cataract occurs in the giant Antarctic toothfish Dissostichus mawsoni lens when cooled to temperatures as low as –12°C, indicating highly cold-stable lens proteins. To investigate this cold stability, we characterised the lens crystallin proteins of the Antarctic toothfish, in parallel with those of the sub-tropical bigeye tuna Thunnus obesusand the endothermic cow Bos taurus, representing three disparate thermal climes (–2°C, 18°C and 37°C, respectively). Sizing chromatography resolved their lens crystallins into three groups,α/βH, β and γ, with γ crystallins being the most abundant (>40%) lens proteins in fish, in contrast to the cow lens where they comprise only 19%. The upper thermal stability of these crystallin components correlated with the body temperature of the species. In vitro chaperone assays showed that fish α crystallin can protect same-species γ crystallins from heat denaturation, as well as lysozyme from DTT-induced unfolding, and therefore are small Heat Shock Proteins (sHSP)like their mammalian counterparts. Dynamic light scattering measured an increase in size of αγ crystallin mixtures upon heating, which supports formation of the αγ complex as an integral part of the chaperone process. Surprisingly, in cross-species chaperone assays, tunaα crystallins only partly protected toothfish γ crystallins, while cow α crystallins completely failed to protect, indicating partial and no αγ interaction, respectively. Toothfish γ was likely to be the component that failed to interact, as the supernatant from a cowα plus toothfish γ incubation could chaperone cow γcrystallins in a subsequent heat incubation, indicating the presence of uncomplexed cow α. This suggests that the inability of toothfish γcrystallins to fully complex with tuna α, and not at all with the cowα crystallins, may have its basis in adaptive changes in the protein that relate to the extreme cold-stability of the toothfish lens.
Partitioning heat loss from mallard ducklings swimming on the air–water interface
Authors: Banta Marilyn R. , Lynott Aaron J. , VanSant Matthew J. , Bakken George S.
Published: December 2004

Water birds whose young begin swimming while downy are interesting because hypothermia and mortality are associated with wetting. While wetting is known to increase heat loss, little is known about basic issues, such as the amount of heat lost to air vs water during surface swimming. To partition heat loss to air and water, we measured the body temperature, metabolism and thermal conductance of 2–3-day-old mallard ducklings (Anas platyrhynchos) swimming under different combinations of air and water temperature. Ventral down remained dry or was wetted only on the surface, and most ducklings could maintain Tb>39°C for 1 h while swimming on water as cold as 5°C. Ducklings were at or below thermal neutrality when swimming in water at Tw=30°C even when air temperature Ta=45°C. Heat loss from ducklings with dry down to air and water was partitioned by fitting data to a heat transfer model of the form M=G(Tb–Tw)+Ke(Tb–Ta). For an average 48 g duckling, thermal conductance to water increased with water temperature, G=0.0470(1+1.059×10–6Tw4)W/°C-animal. Conductance to air was Ke=0.0196 W/°C-animal for all air temperatures. Thus, a minimum of 70% of metabolic heat production is lost to water, and this fraction increases with increasing temperature.
Functional characterisation of theAnophelesleucokinins and their cognate G-protein coupled receptor
Authors: Radford Jonathan C. , Terhzaz Selim , Cabrero Pablo , Davies Shireen-A. , Dow Julian A. T.
Published: December 2004

Identification of the Anopheles gambiae leucokinin gene from the completed A. gambiae genome revealed that this insect species contains three leucokinin peptides, named Anopheles leucokinin I-III. These peptides are similar to those identified in two other mosquito species, Aedes aegypti and Culex salinarius. Additionally, Anopheles leucokinin I displays sequence similarity to Drosophila melanogaster leucokinin.

Using a combination of computational and molecular approaches, a full-length cDNA for a candidate leucokinin-like receptor was isolated from A. stephensi, a close relative of A. gambiae. Alignment of the known leucokinin receptors – all G protein-coupled receptors (GPCRs)– with this receptor, identified some key conserved regions within the receptors, notably transmembrane (TM) domains I, II, III, VI and VII.

The Anopheles leucokinins and receptor were shown to be a functional receptor-ligand pair. All three Anopheles leucokinins caused a dose-dependent rise in intracellular calcium([Ca2+]i) when applied to S2 cells co-expressing the receptor and an aequorin transgene, with a potency order of I>II>III.

Drosophila leucokinin was also found to activate the Anopheles receptor with a similar EC50 value to Anopheles leucokinin I. However, when the Anopheles peptides were applied to the Drosophila receptor, only Anophelesleucokinin I and II elicited a rise in [Ca2+]i. This suggests that the Anopheles receptor has a broader specificity for leucokinin ligands than the Drosophila receptor.

Antisera raised against the Anopheles receptor identified a doublet of approx. 65 and 72 kDa on western blots, consistent with the presence of four N-glycosylation sites within the receptor sequence,and the known glycosylation of the receptor in Drosophila. In Anopheles tubules, as in Drosophila, the receptor was localised to the stellate cells.

Thus we provide the first identification of Anopheles mosquito leucokinins (Anopheles leucokinins) and a cognate leucokinin receptor, characterise their interaction and show that Dipteran leucokinin signalling is closely conserved between Drosophila and Anopheles.
The fluid dynamics of flight control by kinematic phase lag variation between two robotic insect wings
Authors: Maybury Will J. , Lehmann Fritz-Olaf
Published: December 2004

Insects flying with two pairs of wings must contend with the forewing wake passing over the beating hindwing. Some four-winged insects, such as dragonflies, move each wing independently and therefore may alter the relative timing between the fore- and hindwing stroke cycles. The significance of modifying the phase relationship between fore- and hindwing stroke kinematics on total lift production is difficult to assess in the flying animal because the effect of wing-wake interference critically depends on the complex wake pattern produced by the two beating wings. Here we investigate the effect of changing the fore- and hindwing stroke-phase relationship during hovering flight conditions on the aerodynamic performance of each flapping wing by using a dynamically scaled electromechanical insect model. By varying the relative phase difference between fore- and hindwing stroke cycles we found that the performance of the forewing remains approximately constant, while hindwing lift production may vary by a factor of two. Hindwing lift modulation appears to be due to two different fluid dynamic phenomenons: leading edge vortex destruction and changes in strength and orientation of the local flow vector. Unexpectedly, the hindwing regains aerodynamic performance near to that of the wing free from forewing wake interference, when the motion of the hindwing leads the forewing by around a quarter of the stroke cycle. This kinematic relationship between hind- and forewing closely matches the phase-shift commonly used by locusts and some dragonflies in climbing and forward flight. The experiments support previous assumptions that active neuromuscular control of fore- and hindwing stroke phase might enable dragonflies and other functionally four-winged insects to manipulate ipsilateral flight force production without further changes in wing beat kinematics.
Stroke patterns and regulation of swim speed and energy cost in free-ranging Brünnich's guillemots
Authors: Lovvorn James R. , Watanuki Yutaka , Kato Akiko , Naito Yasuhiko , Liggins Geoffrey A.
Published: December 2004

Loggers were attached to free-ranging Brünnich's guillemots Uria lomvia during dives, to measure swim speeds, body angles, stroke rates,stroke and glide durations, and acceleration patterns within strokes, and the data were used to model the mechanical costs of propelling the body fuselage(head and trunk excluding wings). During vertical dives to 102–135 m,guillemots regulated their speed during descent and much of ascent to about 1.6±0.2 m s–1. Stroke rate declined very gradually with depth, with little or no gliding between strokes. Entire strokes from 2 m to 20 m depth had similar forward thrust on upstroke vs downstroke,whereas at deeper depths and during horizontal swimming there was much greater thrust on the downstroke. Despite this distinct transition, these differences had small effect (<6%) on our estimates of mechanical cost to propel the body fuselage, which did not include drag of the wings. Work stroke–1 was quite high as speed increased dramatically in the first 5 m of descent against high buoyancy. Thereafter, speed and associated drag increased gradually as buoyancy slowly declined, so that mechanical work stroke–1 during the rest of descent stayed relatively constant. Similar work stroke–1 was maintained during non-pursuit swimming at the bottom, and during powered ascent to the depth of neutral buoyancy (about 71 m). Even with adjustments in respiratory air volume of ±60%, modeled work against buoyancy was important mainly in the top 15 m of descent, after which almost all work was against drag. Drag was in fact underestimated, as our values did not include enhancement of drag by altered flow around active swimmers. With increasing buoyancy during ascent above 71 m, stroke rate, glide periods, stroke acceleration patterns, body angle and work stroke–1 were far more variable than during descent; however, mean speed remained fairly constant until buoyancy increased rapidly near the surface. For dives to depths >20 m, drag is by far the main component of mechanical work for these diving birds, and speed may be regulated to keep work against drag within a relatively narrow range.
The Police Legitimacy Crisis and Police Law Reform in China: Part I
Authors: Wong Kam C.
Published: December 2004

In 1978 the third plenary session of the Eleventh Central Committee of the Communist Party of China (CCCP) set a new course of development for China, ie modernisation by way of economic reform and market opening. The reform movement changed China socially, politically, economically, and culturally. The gongan or public security is a part of that transformation process. This article is a first attempt to investigate and report upon People's Republic of China (PRC) police law reform effort — objectives, process and result — since 1978. In so doing, the article catalogues the past, describes the present, and speculates upon the future. The paper argues that police law reform in China is a reaction to a growing police legitimacy crisis attenuating the police-public relationship.

This research report will be published in two issues. In this first article, The Police Legitimacy Crisis and Police Law Reform in China: Part I, I will make the case for police law reform in China politically, historically and doctrinally. The second article, The Police Legitimacy Crisis and Police Law Reform in China: Part II, will detail and discuss the direction, promulgation, actualisation and concluding observations of PRC police law reform.
Serial Killers: Offender's Relationship to the Victim and Selected Demographics
Authors: Pakhomou Serge-Moses
Published: December 2004

Currently it is generally accepted among members of the law enforcement community, forensic psychologists, criminologists and profilers that serial killers are mostly white males in their twenties and thirties of above average intelligence who usually commit intra-racial murders of strangers. The present paper focuses on validation of these hypotheses through the study of 21 serial killers (and their 97 victims), whose cases have been closed by arrest and finalised in terms of convictions and appeals. The issues of prior charges, military service, marital status, criminal organisation, modus operandi and psychiatric diagnosis are included in the analysis as well. It is concluded that though currently accepted hypotheses still hold in general, the melting pot trend of the modern society towards diversity and interdependence leads to far more complex a picture of serial killers than previously thought. Implications of these findings for law enforcement, forensic psychology and profiling are discussed.
Dishonest Appropriation after Gomez and Hinks
Authors: Parsons Simon
Published: December 2004

This article examines the meaning of dishonest appropriation in the offence of theft after the House of Lords' decisions in Gomez and Hinks. It maintains that whilst Gomez broke the distinction in the Theft Act 1968 between the simple thief and the deceitful rogue, it did at least maintain the underlying rationale for theft which is the protection of property rights. In contrast Hinks does not comply with this rationale as it allows for the possibility of an appropriation when there was a valid gift of property so that the actus reus of theft no longer requires that there be the composite whole of a ‘dishonest appropriation’. Thus the emphasis in the offence of theft is now on dishonesty and this may be in violation of Articles 5(1) and 7(1) of the European Convention on Human Rights.
Vigilance or Vigilantes: The Paulsgrove Riots and Policing Paedophiles in the Community Part II: The Lessons of Paulsgrove
Authors: Williams Andy , Thompson Bill
Published: December 2004

Following on from Part I this article examines both the media myths surrounding Paulsgrove and the potential strategic and operational lessons that can be learned from this ethnographic study. In doing so we continue our account with a critique of Silke's proposition that the most effective operational response to vigilantism is to exploit media reports of vigilantes' personal weaknesses. In doing so we offer our own alternatives of how to relate to community vigilantism. We believe that by addressing the real origin and nature of the dispute, as opposed to the media myths, we provide alternative options for police forces and MAPPAs (Multi-Agency Public Protection Arrangements) that face the difficult task of managing potentially dangerous offenders in the community against a ***back-drop of high media scrutiny and immense public concern.
Tackling Grooming
Authors: Gillespie Alisdair A.
Published: December 2004

In recent years there has been increasing concern over the use of the internet and other communication technologies to groom children for abuse. The government responded to this pressure by creating an advisory group, The Home Secretary's Internet Task Force on Child Protection, which proposed new legislation, eventually enacted as s. 15 of the Sexual Offences Act 2003. This article explores why this provision was created and considers how it can be used to safeguard children.
Some Correspondences and Similarities of Shamanism and Cognitive Science: Interconnectedness, Extension of Meaning, and Attribution of Mental States
Authors: Hubbard Timothy L.
Published: December 2004

Correspondences and similarities between ideas in shamanism and ideas in contemporary cognitive science are considered. The importance of interconnectedness in the web of life worldview characteristic of shamanism and in connectionist models of semantic memory in cognitive science, and the extension of meaning to elements of the natural world in shamanism and indistributed cognition, are considered. Cognitive consequences of such an extension (e.g., use of representativeness and intentional stance heuristics, magical thinking, social attribution errors, and social in‐group/out‐group differences) are discussed. It is suggested that attributions of mental states, beliefs, and desires to a computer on the basis of behavioral measures (e.g., the Turing test) is consistent with the extension of meaning and intentionality to nonhuman elements of the natural world in shamanism. In general, the existence of such correspondencesand similarities suggests that elements of shamanism may reflect cognitive structures and processes that are also used by nonshamans and in nonshamanic settings.
Outside of social movements: Dilemmas of indigenous handicrafts vendors in Guatemala
Authors: Little Walter E.
Published: December 2004

In Antigua, Guatemala, Maya handicrafts vendors work in a tourism marketplace that brings together multiple ethnolinguistic groups and international visitors. In this article I discuss the interrelationship between occupation and social movements to examine the essentialized identities propagated by the Maya Movement and Ladino racism. I argue that making a living helps shape the interrelated processes of economic and political mobilization. I use work and local political contexts, in particular, to illustrate why vendors do not embrace established social movements.
The culture‐conscious Brazilian Indian: Representing and reworking Indianness in Kayabi political discourse
Authors: Oakdale Suzanne
Published: December 2004

In this article, I examine a Brazilian indigenous people's self‐conscious use of the ideas of “culture” and “Indian ethnicity.” Whereas analysts usually discuss indigenous use of these concepts in the context of high‐profile national or transnational intercultural events, I look at how retrospective accounts of participation in such events are woven into local political discourse. I focus on how two Amazonian leaders represent their participation in past events of cultural display as a means of mounting very different arguments about their eligibility for positions of authority in their community. I argue that local frames of reference, for example, those relating to the culturally appropriate conduct of politics, must be considered in assessing the significance and meaning of cultural performances, even when the staging of indigenous culture is performed principally for a nonlocal audience.
The organization of ideological diversity in discourse: Modern and neotraditional visions of the Tongan state
Authors: Philips Susan U.
Published: December 2004

In current cultural anthropology, under the influence of postmodernism, considerable attention is given to the multiplicity of interpretive perspectives with which people contend in making sense of their daily experiences. In this article I examine diverse representations of the nation‐state in Tonga and other Pacific microstates. My focus is on the configuration of ideological diversity in the Tongan Magistrate's Courts compared with configurations of traditional and modern nationalist ideologies in other Tongan political domains and in other Pacific nations. Some contemporary anthropological accounts represent ideological diversity as plural, fluid, and rapidly changing. Other accounts of ideological diversity emphasize the oppositional structuring of ideas and the power struggle for ideological domination. I argue that it is useful to think of an ecology of ideas, in which multiple ideas move across discourse domains, becoming implanted in hospitable discourse environments, much as plants move into new environments.
National subjects: September 11 and Pearl Harbor
Authors: White Geoffrey M.
Published: December 2004

Despite a long tradition of writing on collective representations of the past, anthropology has contributed relatively little to the expanding literature on national memory. Yet ethnographic approaches have the facility to delineate practices that create historical narrative and give it emotive power while keeping in view longer‐term political forces that underwrite dominant imaginaries. In this article I inquire into the discursive origins of emotional involvement in national history by juxtaposing two events of spectacular violence, September 11 and Pearl Harbor. Focusing on the representation of these events in public culture and at memorial sites, I argue that personal narratives play a central role in formations of national subjectivity, at times emotionalizing dominant memories and at other times opening possibilities for alternative visions.
The aesthetics of absence: Rebuilding Ground Zero
Authors: Sturken Marita
Published: December 2004

In this article, I examine the narratives and meanings that have been projected onto the space of Ground Zero in New York City since September 11, 2001, how they have been deployed for various political agendas, and how they have informed the ways in which the site will be rebuilt and memorialized. I investigate the changing meanings attributed to the dust and the footprints of the World Trade Center buildings and the debates over architectural designs and the proposed memorial.