bluuebunny/crossref_metadata_2025 huggingface dataset:
Xenografting Tumour beneath the Renal Capsule Using Modern Surgical Equipment
Authors: Lawrentschuk Nathan , Rigopoulos Angela , Lee Fook-Thean , Davis Ian D. , Scott Andrew M. , Bolton Damien M.
Published: June 2006

Introduction: The growth of human tumours under the renal capsule in animal models has been performed in the past. However, the use of modern surgical equipment has not always been translated into the laboratory. We report on a novel method for human renal tumour transplants using an automated biopsy gun to obtain tumour tissue and an epidural needle with introducer to easily deploy the grafts under the renal capsule. Methods: Nude mice had human xenografted tumours grown subcutaneously after implantation of cells from culture. Tumours were then biopsied using a 16-gauge automated biopsy gun. Digital calipers were used to measure a 2-mm segment of the biopsy core that was cut and placed inside a hollow needle (epidural needle). The needle was placed under the renal capsule and the trocar introduced to deploy the graft beneath the capsule with minimal trauma. Further groups had tumour harvested similarly by automated biopsy gun but had the implants placed subcutaneously for comparison. Results: Tumour grafts were established in 90% of grafted kidneys in this renal subcapsular model (229.68 ± 118.32 mm3; mean ± 95% CI) which compared favourably to the subcutaneous model (163.81 ± 43.3 mm3). Grafts were confirmed by direct observation and histology. Conclusion: Modern surgical equipment may be utilised to allow tumour transplantation to be precise, with an identifiable and reproducible tumour volume deployed. Surgical researchers and laboratory-based scientists need to embrace new techniques and utilise them to improve models. This model may be adapted to many situations in oncologic research involving xenografting.
Does the Rare A172G Mutation of PTPN11 Gene Convey a Mild Noonan Syndrome Phenotype?
Authors: Kitsiou-Tzeli Sophia , Papadopoulou Anna , Kanaka-Gantenbein Christina , Fretzayas Andreas , Daskalopoulos Dimitris , Kanavakis Emmanuel , Nicolaidou Polyxeni
Published: June 2006

Background: Noonan syndrome (NS) (OMIM 163950) is an autosomal dominant developmental disorder characterized mainly by typical facial dysmorphism, growth retardation and variable congenital heart defects. In unrelated individuals with sporadic or familial NS, heterozygous missense point mutations in the gene PTPN11 (OMIM 176876) have been confirmed, with a clustering of mutations in exons 3 and 8, the mutation A922G (Asn308Asp) accounting for nearly 25% of cases. Patient and Methods: We report a 7-year-old boy with short stature and some other clinical features of NS, who has been investigated by molecular analysis for the presence of mutations in the PTPN11 gene. Result: The de novo mutation A172G in the exon 3 of the PTPN11 gene, predicting an Asn58Asp substitution, has been found. To the best of our knowledge, this specific mutation has only been described once before, but this is the first report of detailed clinical data suggesting a mild phenotype. Conclusion: Detailed clinical phenotype in every patient with major or minor features of NS and molecular identification of PTPN11 gene mutation may contribute to a better phenotype–genotype correlation.
Endothelial Function in Patients with Obstructive Sleep Apnea Syndrome but without Hypertension
Authors: Oflaz Huseyin , Cuhadaroglu Caglar , Pamukcu Burak , Meric Mehmet , Ece Turhan , Kasikcioglu Erdem , Koylan Nevres
Published: June 2006

Background: Obstructive sleep apnea syndrome (OSAS) influences endothelial function and causes hypertension. Objectives: Our aim was to evaluate the role of endothelial dysfunction in the pathogenesis of hypertension in OSAS. Methods: Twenty-three patients with OSAS but without hypertension and 15 healthy normotensive subjects were investigated. The presence or absence of OSAS was evaluated with a sleep study. Endothelial function was investigated with brachial artery ultrasound examination. Results: Baseline characteristics were equivalent between the two groups. Minimal oxygen saturation and apnea-hypopnea indexes in the OSAS and control groups were 62.9 ± 16.5 versus 94.9 ± 1.1% (p < 0.0001) and 53.1 ± 20.3 versus 3.8 ± 0.9 (p < 0.0001), respectively. There was not statistically significant difference between basal brachial artery diameters measured in the morning and in the evening in all groups. Flow-mediated dilation (FMD) values measured in the morning were lower than those measured in the evening in both OSAS patients and the control group: FMD of OSAS patients was 6.04 ± 3.18% in the morning and 10.38 ± 4.23% in the evening hours (p = 0.001), and FMD of control subjects was 10.9 ± 2.6% in the morning and 13.9 ± 2.32 in the evening hours (p = 0.002). Differences in FMD values measured both in the morning and evening hours in OSAS patients were lower compared with those in control subjects (p < 0.0001 in the morning hours and p = 0.003 in the evening hours). Conclusions: We detected a prominent diurnal deterioration in endothelial function in normotensive OSAS patients compared with healthy subjects. This deterioration may occur due to ongoing hypoxemia during the night and it may be a possible cause of hypertension and atherosclerotic cardiovascular diseases in patients with OSAS.
Upregulation of Arginase by H2O2Impairs Endothelium-Dependent Nitric Oxide-Mediated Dilation of Coronary Arterioles
Authors: Thengchaisri Naris , Hein Travis W. , Wang Wei , Xu Xin , Li Zhenbo , Fossum Theresa W. , Kuo Lih
Published: June 2006

Objective—Overproduction of reactive oxygen species such as hydrogen peroxide (H2O2) has been implicated in various cardiovascular diseases. However, mechanism(s) underlying coronary vascular dysfunction induced by H2O2is unclear. We studied the effect of H2O2on dilation of coronary arterioles to endothelium-dependent and endothelium-independent agonists.

Methods and Results—Porcine coronary arterioles were isolated and pressurized without flow for in vitro study. All vessels developed basal tone and dilated dose-dependently to activators of nitric oxide (NO) synthase (adenosine and ionomycin), cyclooxygenase (arachidonic acid), and cytochrome P450 monooxygenase (bradykinin). Intraluminal incubation of vessels with H2O2(100 μmol/L, 60 minutes) did not alter basal tone but inhibited vasodilations to adenosine and ionomycin in a manner similar as that by NO synthase inhibitor L-NAME. H2O2affected neither endothelium-dependent responses to arachidonic acid and bradykinin nor endothelium-independent dilation to sodium nitroprusside. The inhibited adenosine response was not reversed by removal of H2O2but was restored by excess L-arginine. Inhibition of L-arginine consuming enzyme arginase by α-difluoromethylornithine or Nω-hydroxy-nor-l-arginine also restored vasodilation. Administering deferoxamine, an inhibitor of hydroxyl radical production, prevented the H2O2-induced impairment of vasodilation to adenosine. Western blot and reverse-transcription polymerase chain reaction results indicated that arginase I was upregulated after treating vessels with H2O2.

Conclusions—H2O2specifically impairs endothelium-dependent NO-mediated dilation of coronary microvessels by reducing L-arginine availability through upregulation of arginase. The formation of hydroxyl radicals from H2O2may contribute to this process.
Phosphatidylinositol-3-Kinase Regulates Scavenger Receptor Class B Type I Subcellular Localization and Selective Lipid Uptake in Hepatocytes
Authors: Shetty Shoba , Eckhardt Erik R.M. , Post Steven R. , van der Westhuyzen Deneys R.
Published: June 2006

Objective—

The high-density lipoprotein (HDL) receptor scavenger receptor Class B type I (SR-BI) plays a key role in mediating the final step of reverse cholesterol transport. This study examined the possible regulation of hepatic SR-BI by phosphatidylinositol-3-kinase (PI3K), a well known regulator of endocytosis and membrane protein trafficking.

Methods and Results—

SR-BI-dependent HDL selective cholesterol ester uptake in human HepG2 hepatoma cells was decreased (&50%) by the PI3K inhibitors wortmannin and LY294002. Insulin increased selective uptake (&30%), and this increase was blocked by PI3K inhibitors. Changes in SR-BI activity could be accounted for by pronounced changes in the subcellular localization and cell surface expression of SR-BI as determined by HDL cell surface binding, receptor biotinylation studies, and confocal fluorescence microscopy of HepG2 cells expressing green fluorescent protein-tagged SR-BI. Thus, under conditions of PI3K activation by insulin, and to a lesser extent by the SR-BI ligand HDL, cell surface expression of SR-BI was promoted, resulting in increased SR-BI-mediated HDL selective lipid uptake.

Conclusion—

Our data indicate that PI3K activation stimulates hepatic SR-BI function post-translationally by regulating the subcellular localization of SR-BI in a P13K-dependent manner. Decreased hepatocyte PI3K activity in insulin-resistant states, such as type 2 diabetes, obesity, or metabolic syndrome, may impair reverse cholesterol transport by reducing cell surface expression of SR-BI.
Chimeric VEGF-E
NZ7
/PlGF Promotes Angiogenesis Via VEGFR-2 Without Significant Enhancement of Vascular Permeability and Inflammation
Authors: Zheng Yujuan , Murakami Masato , Takahashi Hiroyuki , Yamauchi Mai , Kiba Atsushi , Yamaguchi Sachiko , Yabana Naoyuki , Alitalo Kari , Shibuya Masabumi
Published: June 2006

Objective—

Vascular endothelial growth factor (VEGF) plays critical roles in the regulation of angiogenesis and lymphangiogenesis. However, tissue edema, hemorrhage, and inflammation occur when VEGF-A is used for angiogenic therapy. To design a novel angiogenic factor without severe side effects, we examined the biological function of chimeric VEGF-E
NZ7
/placental growth factor (PlGF), which is composed of Orf-Virus
NZ7
-derived VEGF-E
NZ7
and human PlGF1, in a transgenic (Tg) mouse model.

Methods and Results—

A strong angiogenic response was observed in both VEGF-E
NZ7
/PlGF and VEGF-A
165
Tg mice. Notably, the vascular leakage of VEGF-E
NZ7
/PlGF-induced blood vessels was 4-fold lower than that of VEGF-A
165
–induced blood vessels. Furthermore, the monocyte/macrophage recruitment in the skin of VEGF-E
NZ7
/PlGF Tg mice was &8-fold decreased compared with that of VEGF-A
165
Tg mice. In addition, the lymphatic vessels in VEGF-E
NZ7
/PlGF Tg mice were structurally normal, whereas they were markedly dilated in VEGF-A
165
Tg mice, possibly because of the high vascular leakage. Receptor binding assay demonstrated that VEGF-E
NZ7
/PlGF was the ligand only activating VEGF receptor (VEGFR)-2.

Conclusion—

These results indicated that neither the hyperpermeability in response to simultaneous stimulation of VEGFR-1 and VEGFR-2 nor VEGFR-1–mediated severe inflammation was associated with VEGF-E
NZ7
/PlGF-induced angiogenesis. The unique receptor binding property may shed light on VEGF-E
NZ7
/PlGF as a novel candidate for therapeutic angiogenesis.
Identification of Sokotrasterol Sulfate As a Novel Proangiogenic Steroid
Authors: Murphy Siun , Larrivée Bruno , Pollet Ingrid , Craig Kyle S. , Williams David E. , Huang Xin-Hui , Abbott Megan , Wong Fred , Curtis Cameron , Conrads Thomas P. , Veenstra Timothy , Puri Mira , Hsiang York , Roberge Michel , Andersen Raymond J. , Karsan Aly
Published: June 2006

The potential to promote neovascularization in ischemic tissues using exogenous agents has become an exciting area of therapeutics. In an attempt to identify novel small molecules with angiogenesis promoting activity, we screened a library of natural products and identified a sulfated steroid, sokotrasterol sulfate, that induces angiogenesis in vitro and in vivo. We show that sokotrasterol sulfate promotes endothelial sprouting in vitro, new blood vessel formation on the chick chorioallantoic membrane, and accelerates angiogenesis and reperfusion in a mouse hindlimb ischemia model. We demonstrate that sulfation of the steroid is critical for promoting angiogenesis, as the desulfated steroid exhibited no endothelial sprouting activity. We thus developed a chemically synthesized sokotrasterol sulfate analog, 2β,3α,6α-cholestanetrisulfate, that demonstrated equivalent activity in the hindlimb ischemia model and resulted in the generation of stable vessels that persisted following cessation of therapy. The function of sokotrasterol sulfate was dependent on cyclooxygenase-2 activity and vascular endothelial growth factor induction, as inhibition of either cyclooxygenase-2 or vascular endothelial growth factor blocked angiogenesis. Surface expression of α
v
β
3
integrin was also necessary for function, as neutralization of α
v
β
3
integrin, but not β
1
integrin, binding abrogated endothelial sprouting and antiapoptotic activity in response to sokotrasterol sulfate. Our findings indicate that sokotrasterol sulfate and its analogs can promote angiogenesis in vitro and in vivo and could potentially be used for promoting neovascularization to relieve the sequelae of vasoocclusive diseases.
Activation of the Unfolded Protein Response in Infarcted Mouse Heart and Hypoxic Cultured Cardiac Myocytes
Authors: Thuerauf Donna J. , Marcinko Marie , Gude Natalie , Rubio Marta , Sussman Mark A. , Glembotski Christopher C.
Published: June 2006

Endoplasmic reticulum (ER) stresses that reduce ER protein folding activate the unfolded protein response (UPR). One effector of the UPR is the transcription factor X-box binding protein-1 (XBP1), which is expressed on ER stress-mediated splicing of the XBP1 mRNA. XBP1 induces certain ER-targeted proteins, eg, glucose-regulated protein 78 (GRP78), that help resolve the ER stress and foster cell survival. In this study, we determined whether hypoxia can activate the UPR in the cardiac context. Neonatal rat ventricular myocyte cultures subjected to hypoxia (16 hours) exhibited increased XBP1 mRNA splicing, XBP1 protein expression, GRP78 promoter activation, and GRP78 protein levels; however, the levels of these UPR markers declined during reoxygenation, suggesting that the UPR is activated during hypoxia but not during reoxygenation. When cells were infected with a recombinant adenovirus (AdV) encoding dominant-negative XBP1 (AdV-XBP1dn), UPR markers were reduced; however, hypoxia/reoxygenation-induced apoptosis increased. Confocal immunocytofluorescence demonstrated that hypoxia induced GRP78 in neonatal rat and isolated adult mouse ventricular myocytes. Moreover, mouse hearts subjected to in vivo myocardial infarction exhibited increased GRP78 expression in cardiac myocytes near the infarct, but not in healthy cells distal to the infarct. These results indicate that hypoxia activates the UPR in cardiac myocytes and that XBP1-inducible proteins may contribute to protecting the myocardium during hypoxic stress.
A Zebrafish Model of Human Barth Syndrome Reveals the Essential Role of Tafazzin in Cardiac Development and Function
Authors: Khuchua Zaza , Yue Zou , Batts Lorene , Strauss Arnold W.
Published: June 2006

Barth syndrome is an X-linked disorder characterized by cardiomyopathy, skeletal myopathy, neutropenia, organic aciduria, and growth retardation caused by mutations in tafazzin. The sequence similarity of tafazzin to acyltransferases suggests a role in mitochondrial phospholipid metabolism. To study the role of tafazzin in heart function and development, we created a knockdown zebrafish model. Zebrafish tafazzin mRNA is first evident at 7 hours post-fertilization (hpf). At 10 and 24 hpf, tafazzin mRNA is ubiquitous, with highest levels in the head. By 51 hpf, expression becomes cardiac restricted. The tafazzin knockdown created by antisense morpholino yolk injection resulted in dose-dependent lethality, severe developmental and growth retardation, marked bradycardia and pericardial effusions, and generalized edema, signs that resemble human Barth syndrome heart failure. This knockdown phenotype was rescued by concomitant injection of normal tafazzin mRNA. Abnormal cardiac development, with a linear, nonlooped heart, and hypomorphic tail and eye development proves that tafazzin is essential for overall zebrafish development, especially of the heart. The tafazzin knockdown zebrafish provides an animal model similar to Barth syndrome to analyze the severity of human mutants and to test potential treatments.
Central Compensation at Short Muscle Range Is Differentially Affected in Cortical Versus Subcortical Strokes
Authors: Renner Caroline I.E. , Woldag Hartwig , Hummelsheim Horst
Published: June 2006

Background and Purpose—

The active force generated by a single muscle fiber is greatest in midrange. In healthy subjects, the reduced muscle force at short muscle length is partially compensated by modified patterns of muscle activation, probably central in origin. These patterns are presumed to be deficient after stroke. We examined the excitability muscle-length relation in stroke patients and healthy controls and hypothesized about its alteration in stroke patients.

Methods—

Corticospinal excitability was assessed in 31 stroke patients (19 subcortical, 12 cortical) and 19 healthy volunteers by transcranial magnetic stimulation. We recorded the motor evoked potentials (MEPs) simultaneously from the biceps brachii and the triceps brachii muscles at 0°, 20°, 40°, 60°, 80°, 100°, and 120° degrees of elbow flexion (0° being full elbow extension).

Results—

Normal subjects revealed a significant increase in MEP amplitudes at shortened muscle lengths for both the flexor and extensor muscles (
P
<0.001). Multivariate variance analysis revealed that the MEP-angle curves of cortical stroke patients were significantly different from those of the control group for both muscles, lacking an increase of corticospinal excitability at short muscle length. Yet the MEP-angle curves for the subcortical stroke patients did not show a statistically significant difference from the control group for either muscle.

Conclusion—

Cortical and subcortical strokes differentially affect the corticospinal excitability muscle-length relation. This may account for the reported disproportionate decrease in muscle strength at shortened range after stroke.
Neglecting the Difference
Authors: Legge Silvia Di , Saposnik Gustavo , Nilanont Yongchai , Hachinski Vladimir
Published: June 2006

Background and Purpose—

Patients with right hemispheric strokes (RHSs) present later to an emergency department, have a lower chance to receive intravenous recombinant tissue plasminogen activator (IV rt-PA), and have worse clinical outcomes than do patients with left hemispheric strokes (LHSs). We analyzed outcomes after IV rt-PA with respect to the side of the affected hemisphere.

Methods—

A prospective cohort of acute stroke patients was treated with IV rt-PA at the London Health Sciences Centre (December 1998 to March 2003). Differences between patients with RHS and LHS were identified by univariate analysis. Logistic-regression analysis was used to determine a subset of variables independently associated with major neurological improvement at 24 hours and good outcome at 3 months after treatment.

Results—

Of 219 stroke patients who received IV rt-PA, 165 had hemispheric strokes (68 RHSs and 97 LHSs). Patients with RHSs were less hypertensive (
P
=0.001) and had lower pretreatment National Institutes of Health Stroke Scale (NIHSS) scores (
P
=0.005). LHS (odds ratio [OR], 2.29; 95% CI, 1.14 to 4.59;
P
=0.019), age (OR, 0.96; 95% CI, 0.93 to 0.99;
P
=0.012), and pretreatment NIHSS (OR, 0.83; 95% CI, 0.78 to 0.89;
P
<0.0001) were independent predictors of 3-month outcome. Female sex (OR, 3; 95% CI, 1.53 to 5.90;
P
=0.001) and LHS (OR, 2.07; 95% CI, 1.05 to 4.08;
P
=0.03) were independent predictors of major neurological improvement at 24 hours after IV rt-PA.

Conclusions—

Despite higher pretreatment NIHSS, patients with LHSs have a 2-fold increased chance of a good outcome 3 months after rt-PA treatment compared with patients with RHSs. This gain can be clinically detected at 24 hours after treatment. These results need to be coupled with neuroimaging and hemodynamic characteristics known to influence stroke outcome.
Analysis of Thrombi Retrieved From Cerebral Arteries of Patients With Acute Ischemic Stroke
Authors: Marder Victor J. , Chute Dennis J. , Starkman Sidney , Abolian Anna M. , Kidwell Chelsea , Liebeskind David , Ovbiagele Bruce , Vinuela Fernando , Duckwiler Gary , Jahan Reza , Vespa Paul M. , Selco Scott , Rajajee Venkatakrishna , Kim Doojin , Sanossian Nerses , Saver Jeffrey L.
Published: June 2006

Background and Purpose—

Information regarding the histological structure of thromboemboli that cause acute stroke provides insight into pathogenesis and clinical management.

Methods—

This report describes the histological analysis of thromboemboli retrieved by endovascular mechanical extraction from the middle cerebral artery (MCA) and intracranial carotid artery (ICA) of 25 patients with acute ischemic stroke.

Results—

The large majority (75%) of thromboemboli shared architectural features of random fibrin:platelet deposits interspersed with linear collections of nucleated cells (monocytes and neutrophils) and confined erythrocyte-rich regions. This histology was prevalent with both cardioembolic and atherosclerotic sources of embolism. “Red” clots composed uniquely of erythrocytes were uncommon and observed only with incomplete extractions, and cholesterol crystals were notably absent. The histology of thromboemboli that could not be retrieved from 29 concurrent patients may be different. No thrombus >3 mm wide caused stroke limited to the MCA, and no thrombus >5 mm wide was removed from the ICA. A mycotic embolus was successfully removed in 1 case, and a small atheroma and attached intima were removed without clinical consequence from another.

Conclusions—

Thromboemboli retrieved from the MCA or intracranial ICA of patients with acute ischemic stroke have similar histological components, whether derived from cardiac or arterial sources. Embolus size determines ultimate destination, those >5 mm wide likely bypassing the cerebral vessels entirely. The fibrin:platelet pattern that dominates thromboembolic structure provides a foundation for both antiplatelet and anticoagulant treatment strategies in stroke prevention.
Estimation of the Risk of Stroke in Black Populations in Barbados and South London
Authors: Wolfe Charles D.A. , Corbin David O.C. , Smeeton Nigel C. , Gay Glenda H.E. , Rudd Anthony G. , Hennis Anselm J. , Wilks Rainford J. , Fraser Henry S.
Published: June 2006

Background and Purpose—

The incidence of stroke in black populations is a public health issue, but how risk varies between black communities is unclear.

Methods—

Population-based registers in South London (SLSR) and Barbados (Barbados Register of Strokes [BROS]). Stroke incidence estimated by age group, gender and stroke subtype from January 1995 to December 2002 (SLSR), and October 2001 to September 2003 (BROS). Incidence rate ratios [IRR] estimated adjusting for age and sex.

Results—

Two hundred and seventy-one cases registered in SLSR and 628 cases in BROS. Average age of stroke was 66.1 years (SD 13.7) in SLSR and 71.5 years (SD 14.9) in BROS (
P
<0.001). The incidence rate/1000 population in SLSR was 1.61 (European adjusted; 95% CI, 1.41 to 1.81) and 1.08 (world adjusted; 95% CI, 0.95 to 1.21). For Barbados incidence rates were 1.29 (European adjusted; 95% CI, 1.19 to1.39) and 0.85 (world adjusted; 95% CI, 0.78 to 0.92). Overall IRR for SLSR: BROS adjusted for age and sex was 1.26 (95% CI, 1.09 to 1.46). Statistically significant subtype differences included total anterior cerebral infarction (IRR, 1.82; 95% CI, 1.23 to 2.69), posterior cerebral infarction (IRR, 2.12; 95% CI, 1.28 to 3.53), primary intracerebral hemorrhage (IRR, 1.56; 95% CI, 1.03 to 2.35) and subarachnoid hemorrhage (IRR, 5.04; 95% CI, 2.54 to 9.97).

Conclusions—

The risk of stroke in black Caribbeans is higher in South London than Barbados, and particularly so for specific stroke subtypes. The risk in Barbados approaches that in the white population in South London and strokes occur at an older age. Whether environmental factors mediate these differences in migrant populations requires further study.
Geographic Variations in Stroke Incidence and Mortality Among Older Populations in Four US Communities
Authors: El-Saed Aiman , Kuller Lewis H. , Newman Anne B. , Lopez Oscar , Costantino Joseph , McTigue Kathleen , Cushman Mary , Kronmal Richard
Published: June 2006

Background and Purpose—

Stroke is a leading cause of death and disability in the US. There is limited data on geographic variations in stroke incidence among older US populations who experience the majority of stroke burden. The purpose of this study was to compare stroke incidence and mortality rates in 4 US communities.

Methods—

Participants in the Cardiovascular Health Study (CHS) who had no history of stroke at baseline (n=5639) were followed for 10 or 7 years in predominantly white (n=5002) and black (n=637) participants, respectively. Incident stroke was validated by a stroke adjudication committee after ascertainment at annual visits, interim telephone contacts, and review of Medicare hospitalization data.

Results—

The 2000 US population age and sex standardized total stroke incidence rate for all CHS participants was 17.7 per 1000 person-years (95% CI: 15.9, 19.5). The rate was significantly lower in Allegheny County, Pennsylvania 9.6/1000 person-years (95% CI: 7.7, 11.5) than Forsyth County, North Carolina 19.2/1000 person-years (95% CI: 15.6, 22.8), Sacramento County, California 20.7/1000 person-years (95% CI: 16.9, 24.5), and Washington County, Maryland 19.8/1000 person-years (95% CI: 16.1, 23.5). The lower stroke incidence rate in Allegheny County was consistent in gender, race, and age groups. Though not statistically significant, stroke mortality was also lower in Allegheny County than other 3 sites. The 1-month case fatality rate was similar in the 4 sites for all strokes, and by stroke types.

Conclusions—

Understanding geographic variations in stroke incidence may be an important step in improving preventive practices of stroke.
On the Time Scale of Nocturnal Boundary Layer Cooling in Valleys and Basins and over Plains
Authors: De Wekker Stephan F. J. , Whiteman C. David
Published: June 2006

Sequences of vertical temperature soundings over flat plains and in a variety of valleys and basins of different sizes and shapes were used to determine cooling-time-scale characteristics in the nocturnal stable boundary layer under clear, undisturbed weather conditions. An exponential function predicts the cumulative boundary layer cooling well. The fitting parameter or time constant in the exponential function characterizes the cooling of the valley atmosphere and is equal to the time required for the cumulative cooling to attain 63.2% of its total nighttime value. The exponential fit finds time constants varying between 3 and 8 h. Calculated time constants are smallest in basins, are largest over plains, and are intermediate in valleys. Time constants were also calculated from air temperature measurements made at various heights on the sidewalls of a small basin. The variation with height of the time constant exhibited a characteristic parabolic shape in which the smallest time constants occurred near the basin floor and on the upper sidewalls of the basin where cooling was governed by cold-air drainage and radiative heat loss, respectively.
Contending With Financial Inequality
Authors: John Edward P.
Published: June 2006

Researchers frequently focus on the roles of background and academic preparation in college access without considering the role of family income. The theory on cultural capital provides a lens for examining the role of family income in education decisions. This article uses the theory of cultural capital, along with claims from other theories, to examine interviews with students who received substantial grant awards. The analyses help illuminate that student perceptions of finances influence social and academic decisions about higher education, illustrating that qualitative research can contribute substantially to the emerging understanding of financial inequality in educational opportunity.
Examining the Tangible and Psychosocial Benefits of Financial Aid With Student Access, Engagement, and Degree Attainment
Authors: Nora Amaury , Barlow Libby , Crisp Gloria
Published: June 2006

Research on financial assistance points out the impact of aid on academic achievement, educational commitments, student engagement, and persistence to graduation. What is more, the availability of funds to meet tuition and other college-going expenses not only bears on a student’s decision to attend college but also affects to a great extent the choice of college made by that student. This article looks at the influence that financial aid exerts on different aspects of a student’s life, provides a financial aid profile of first-time-in-college students across 6 academic years, and reviews different financial resources used by low-income students.
Rehabilitating Duverger’s Theory
Authors: Clark William Roberts , Golder Matt
Published: June 2006

Although Duverger is traditionally seen as synonymous with the institution-list approach to party systems, this article shows that he believed social pressures were the driving force behind the multiplication of parties. Electoral institutions are important, but only because they determine the extent to which social forces are translated into political parties. Although the literature has finally come to realize that social and institutional forces interact to shape party systems, scholars still do not seem to fully understood the implications of Duverger’s theory. This article shows that existing research employs flawed statistical specifications, makes inferential errors, and does not calculate desired quantities of interest. Using a new data set that includes elections since 1946, the authors reexamine Duverger’s theory and find that modern tests largely bear out his expectations when properly specified and interpreted. This analysis also extends current research by specifically estimating the mechanical and strategic modifying effects of electoral institutions.
Compared to What?
Authors: Armijo Leslie Elliott , Faucher Philippe , Dembinska Magdalena
Published: June 2006

A rich and plausible academic literature has delineated reasons to believe Brazil’s democratic political institutions—including electoral rules, the political party system, federalism, and the rules of legislative procedure—are suboptimal from the viewpoints of democratic representativeness and policy-making effectiveness. The authors concur that specific peculiarities of Brazilian political institutions likely complicate the process of solving societal collective action dilemmas. Nonetheless, Brazil’s economic and social track record since redemocratization in the mid-1980s has been reasonably good in comparative regional perspective. Perhaps Brazil’s informal political negotiating mechanisms, or even other less obvious institutional structures, provide sufficient countervailing influences to allow “governance” to proceed relatively smoothly despite the appearance of chaos and political dysfunction.
The role of registration in ensuring ethical practice
Authors: Orme Joan , Rennie Gavin
Published: June 2006

English

This article compares the processes of registration of social workers in the UK and New Zealand. Its findings are that registration is linked, not to the development of codes of ethics, but to regulation based on codes of conduct. This leads to a discussion of the implications for ethical practice.

French

Cet article compare les processus d'inscription des travailleurs sociaux au Royaume Uni et en Nouvelle Zélande. Les résultats de la recherche démontrent que l'inscription n'est pas liée au développement d'un code d'éthique mais plutôt à des règles fondées sur un code de conduite. L'article discute des implications pour une pratique éthique.

Spanish

Se compara el proceso de colegiación de trabajadores sociales en el Reino Unido y en Nueva Zelanda. Se halla que la colegiación está ligada no al desarrollo de códigos éticos, sino a regulaciones basadas en códigos de conducta. De ahí se deriva una exploración de las implicaciones para la práctica ética.
Urban Australian Aboriginal peoples’ experience of human services
Authors: Baldry Eileen , Green Sue , Thorpe Katrina
Published: June 2006

English

Urban Aboriginal communities were asked about their experiences of human services. The misuse of Aboriginal liaison staff, the attitudes of staff and policy-makers, the invisibility of Aboriginal clients, poor communication, lack of access to services, client rights and lack of integration were raised. Respect for Aboriginal persons’ social citizenship is discussed.

French

Il a été demandé aux communautés aborigènes urbaines de décrire leur expérience des services humains disponibles. Les dilemmes suivants ont été soulevés: une mauvaise utilisation des employés assurant la liaison, certaines attitudes d'employés et de développeurs de politiques, un manque de visibilité de la clientèle aborigène, des communications déficientes, des difficultés d'accès aux services, les droits des clients et un manque d'intégration. Une discussion sur le respect pour la citoyenneté sociale des personnes aborigènes est présentée dans l'article.

Spanish

Se pidió información a las comunidades aborígenes urbanas sobre sus experiencias como usuarios de los servicios humanos. Se trataron los siguientes temas: el mal uso de los empleados aborígenes en su función conectora, las actitudes de los empleados y políticos, la invisibilidad del cliente aborigen, la mala comunicación, la falta de acceso a los servicios, la falta de integración, y cuestiones de derechos del cliente. Se explora la cuestión de la ciudadanía social de los aborígenes.
Broadening the vision
Authors: Braye Suzy , Preston-Shoot Michael
Published: June 2006

English

In the context of debates about social work’s relationship with individuals, the state and civil society, educators face a challenge. How best to ensure that professional education prepares practitioners to engage with the task of promoting social justice and human rights? This article draws on a systematic knowledge review of learning, teaching and assessment of one key subject area in social work education - that of law - to explore the contribution legal knowledge and skills can make to social work’s engagement with its vision of empowerment and liberation.

French

Dans le contexte des débats concernant les interactions entre travailleurs sociaux, individus, l'Ütat et la société civile, les éducateurs font face à des défis. Comment s'assurer que la formation professionnelle prépare les futurs praticiens à s'engager dans la promotion de la justice sociale et des droits humains? Cet article est fondé sur une recension systématique des connaissances sur l'apprentissage, l'enseignement et l'évaluation d'un sujet clé dans la formation des travailleurs sociaux, celui du droit. Il explore la contribution que le développement des connaissances et des habiletés en matières légales peut accomplir pour l'implication des travailleurs sociaux dans 'l'empowerment' et la libération, tels que stipulés dans la définition internationale du travail social en tant que vision de ce travail.

Spanish

Los educadores de trabajo social tienen ante sí un reto: la relación entre individuos, el estado y la sociedad civil 'Cómo asegurarse que la formación profesional ayude a la promoción de la justicia social y los derechos humanos? Se hace una revisión sistemática del aprendizaje, enseñanza y evaluación de un área clave en la formación del trabajador social el de la ley. Se explora cómo el conocimiento y las destrezas legales pueden contribuir a la visión de apoderamiento y liberación propia del trabajo social.
Cyberage Narratives
Authors: Klerfelt Anna
Published: June 2006

In this article two computer-produced multimedia stories created by children in their after-school centre are analysed, building on the assumption that children draw that which is important for them. The aim is to make visible the significance of narrative structure, reaccentuation, intertextuality, multivoicedness and various levels of interpretation. The author discusses how the stories spring from the children’s everyday social practice and mirror their contemporary media culture. In conclusion, the author advances the need for the appropriation of a socially shared symbolic system within the chosen genre through participation in social practices
The Ethical Maze
Authors: Cocks Alison J.
Published: June 2006

In the UK, the ethics of engaging in sociological research directly involving children have primarily been shaped by definitions of ‘competence’. While this has been a crucial guideline for researchers in shaping the concept of informed consent, it has also acted, perhaps inadvertently, as a way of excluding particular children from the research agenda. This article discusses the problems of informed consent that were encountered in research with children with learning impairments. It proposes that the process of seeking ‘assent’, when used within an ethical framework, is a more comprehensive method of gaining the agreement of children in research, which transcends language, ability, cultural, social and international borders
Corporal Punishment in Cross-Cultural Perspective: Directions for a Research Agenda
Authors: Ripoll-Núñez Karen J. , Rohner Ronald P.
Published: June 2006

This article discusses major issues in corporal punishment research and identifies directions for improvement of current knowledge about this disciplinary practice. Conceptual and methodological problems in existing corporal punishment research are discussed. The authors also highlight research challenges that lie ahead. These include the need for (a) an explicit and consistently used definition of physical punishment, (b) the development of an assessment procedure that includes the full range of variables important in understanding corporal punishment and its effects, (c) the evaluation of children’s own perception of punishment, (d) the assessment of third variables, and (e) the evaluation of nonlinear relations between corporal punishment and child outcomes. The authors present parental acceptance-rejection theory’s (PARTheory’s) research agenda that attempts to address all these issues.
Youths’ Perceptions of Corporal Punishment, Parental Acceptance, and Psychological Adjustment in a Turkish Metropolis
Authors: Erkman Fatoş , Rohner Ronald P.
Published: June 2006

This study explored relations among corporal punishment, perceived parental acceptance, and the psychological adjustment of 427 Turkish youths between the ages of 10 to 18. Participants responded in school to the child versions of the Physical Punishment Questionnaire, Parental Acceptance-Rejection Questionnaire, Personality Assessment Questionnaire, and a demographic questionnaire. Results of multiple regression analyses showed that youths’ perceptions of both maternal and paternal acceptance made independent and significant contributions to variations in youths’ self-reported psychological adjustment. Regression analyses also showed that neither maternal nor paternal punishment by themselves made significant contributions to variations in youths’ adjustment when the influence of perceived maternal and paternal acceptance was controlled. Thus, we concluded that apparent relations between parental punishment and youths’ psychological adjustment were almost completely mediated by youths’ perceptions of parental acceptance. Neither youths’ gender nor age was associated with either perceived parental acceptance or punishment.
“Just Another Native?” Soundscapes, Chorasters, and Borderlands in Edmonton, Alberta, Canada
Authors: Lashua Brett D.
Published: June 2006

This article discusses soundscapes created by young people participating in The Beat of Boyle Street, an in-school recreation-based project that teaches inner-city, at-risk youth to make music using computers and audio production software. Participants are predominantly Aboriginal youth, ages 14 to 20, living in poverty and confronting other challenges, including disabilities, addictions, parenting issues, racism, homelessness, and the vicissitudes of life “on the streets.” The soundscape compositions young people create tell stories that speak to the importance of what young people actually do with popular culture in their everyday lives, particularly with hip-hop music and style. Three soundscape examples provided indicate how young people (a) use and negotiate popular culture, (b) politically use and contest city spaces, and (c) act as “border crossers.” These points call attention to the power of popular cultural practices as leisure and provide insights for working with young people in recreational contexts.
‘Animals Do It Too!’: The Franklin Defence of Meat-Eating
Authors: Telfer Elizabeth
Published: June 2006

The Franklin defence of meat-eating is the claim that meat-eating is morally permissible because animals eat other animals. I examine five versions of this defence. I argue that two versions, claiming respectively that might is right and that animals deserve to be eaten, can easily be dismissed, and that the version based on a claim that God intends us to eat animals is theologically controversial. I go on to show that the two other versions—one claiming that meat-eating is natural, the other that it is inconsistent to condemn human meat-eating without also trying to prevent animals eating other animals—present some difficulties for the moral vegetarian.
Hypogammaglobulinemia and exacerbated CD8 T-cell–mediated immunopathology in SAP-deficient mice with chronic LCMV infection mimics human XLP disease
Authors: Crotty Shane , McCausland Megan M. , Aubert Rachael D. , Wherry E. John , Ahmed Rafi
Published: June 2006

The human genetic disease X-linked lymphoproliferative disease (XLP), which is caused by mutations in SH2D1A/SAP that encode SLAM-associated protein (SAP), is characterized by an inability to control Epstein-Barr virus (EBV) and hypogammaglobulinemia. It is unclear which aspects of XLP disease are specific to herpesvirus infection and which reflect general immunologic functions performed by SAP. We examined SAP– mice during a chronic LCMV infection, specifically to address the following question: Which SAP deficiency immunologic problems are general, and which are EBV specific? Illness, weight loss, and prolonged viral replication were much more severe in SAP– mice. Aggressive immunopathology was observed. This inability to control chronic LCMV was associated with both CD8 T-cell and B-cell response defects. Importantly, we demonstrate that SAP– CD8 T cells are the primary cause of the immunopathology and clinical illness, because depletion of CD8 T cells blocked disease. This is the first direct demonstration of SAP– CD8 T-cell–mediated immunopathology, confirming 30 years of XLP clinical observations and indirect experimentation. In addition, germinal center formation was extremely defective in chronically infected SAP– animals, and hypogammaglobulinemia was observed. These findings in a chronic viral infection mouse model recapitulate key features of human XLP and clarify SAP's critical role regulating both cellular and humoral immunity.
Dysregulation of IL-15-mediated T-cell homeostasis in TGF-β dominant-negative receptor transgenic mice
Authors: Lucas Philip J. , Kim Seong-Jin , Mackall Crystal L. , Telford William G. , Chu Yu-Waye , Hakim Frances T. , Gress Ronald E.
Published: June 2006

T-cell subpopulations, defined by their expression of CD4, CD8, naive, and memory cell-surface markers, occupy distinct homeostatic compartments that are regulated primarily by cytokines. CD8+ memory T cells, as defined by CD44hi surface expression, are dependent on IL-15 as a positive regulator of their homeostatic maintenance. Manipulation of IL-15 signaling through gene aberration, overexpression, or receptor alterations has been shown to dramatically affect T-cell homeostasis, with overexpression leading to fatal leukemia. Here we show that TGF-β is the critical negative regulator of murine CD8+ memory T-cell homeostasis with direct opposition to the positive effects of IL-15. This negative regulation is mediated, at least in part, by the ability of TGF-β to modulate expression of the β-chain of the IL-15 receptor, thus establishing a central axis between these 2 cytokines for homeostatic control of CD8+ memory T-cell populations. These data establish TGF-β as a critical and dominant tumor-suppressor pathway opposing IL-15-mediated CD8+ T-cell expansion and potential malignant transformation.
Bacterial genotyping by 16S rRNA mass cataloging
Authors: Jackson George W , McNichols Roger J , Fox George E , Willson Richard C
Published: June 2006

Background

It has recently been demonstrated that organism identifications can be recovered from mass spectra using various methods including base-specific fragmentation of nucleic acids. Because mass spectrometry is extremely rapid and widely available such techniques offer significant advantages in some applications. A key element in favor of mass spectrometric analysis of RNA fragmentation patterns is that a reference database for analysis of the results can be generated from sequence information. In contrast to hybridization approaches, the genetic affinity of any unknown isolate can in principle be determined within the context of all previously sequenced 16S rRNAs without prior knowledge of what the organism is. In contrast to the original RNase T1cataloging method, when digestion products are analyzed by mass spectrometry, products with the same base composition cannot be distinguished. Hence, it is possible that organisms that are not closely related (having different underlying sequences) might be falsely identified by mass spectralcoincidence. We present a convenient spectral coincidence function for expressing the degree of similarity (or distance) between any two mass-spectra. Trees constructed using this function are consistent with those produced by direct comparison of primary sequences, demonstrating that the inherent degeneracy in mass spectrometric analysis of RNA fragments does not preclude correct organism identification.

Results

Neighbor-joining trees for important bacterial pathogens were generated using distances based on mass spectrometric observables and the spectral coincidence function. These trees demonstrate that most pathogens will be readily distinguished using mass spectrometric analyses of RNA digestion products. A more detailed, genus-level analysis of pathogens and near relatives was also performed, and it was found that assignments of genetic affinity were consistent with those obtained by direct sequence comparisons. Finally, typical values of the coincidence between organisms were also examined with regard to phylogenetic level and sequence variability.

Conclusion

Cluster analysis based on comparison of mass spectrometric observables using the spectral coincidence function is an extremely useful tool for determining the genetic affinity of an unknown bacterium. Additionally, fragmentation patterns can determine within hours if an unknown isolate is potentially a known pathogen among thousands of possible organisms, and if so, which one.