bluuebunny/crossref_metadata_2025 huggingface dataset:
Colour Doppler ultrasonographic location of the bulbourethral artery, and its impact on surgical outcome
Authors: Kishore Thekke Adiyat , Bhat Suresh , John Roy P.
Published: August 2005

OBJECTIVE

To assess the location of bulbourethral arteries in men with a ‘normal’ urethra and to study anatomical alterations in men with urethral stricture.

PATIENTS AND METHODS

A linear‐array transducer was used on the ventral surface of the penis to study the urethra. Fifteen men with a normal urethra and 15 with a stricture of the bulbar urethra were assessed. After conventional grey‐scale imaging to evaluate the extent of disease, the urethral artery in the bulbar urethra was located by colour Doppler ultrasonography.

RESULTS

The site of the urethral arteries in ‘normal’ men varied among individuals; they were at the 10–2 o’clock position in six men, 8–10 o’clock and 2–4 o’clock in six, and at the 4–8 o’clock position in three. In normal men the symmetry of arteries was maintained and the mean distance from the lumen was 2.67 mm. In men with urethral stricture, there was a loss of symmetry in all cases. In a dense stricture the urethral arteries could not be detected on either side in three of cases, while only a single artery was seen in three. In two men, both the arteries were on one side. The mean distance of the urethral artery from the lumen of urethra was 1.88 mm.

CONCLUSIONS

Contrary to the popular belief that the urethral arteries are located at the 3 and 9 o’clock position, we found that there was no predictable pattern for their anatomy. These observations might have implications for treating urethral stricture disease with visual internal urethrotomy, as they could help to avoid injury to the bulbourethral artery.
Refractory monosymptomatic nocturnal enuresis: a combined stepwise approach in childhood and follow‐up into adolescence, with attention to the clinical value of normalizing bladder capacity
Authors: Vermandel Alexandra , De Wachter Stefan , Wyndaele Jean‐Jacques
Published: August 2005

There are two papers in the paediatric urology section this month. The first, from Belgium, assessed the importance of normalising bladder capacity to the age‐expected capacity in children with refractory nocturnal enuresis, and evaluated the long‐term results when the children reached adolescence. The second paper from the USA assessed the role of apoptosis and proliferation in children with undescended testes.

OBJECTIVE

To assess the importance of normalizing bladder capacity to the age‐expected capacity in children with refractory monosymptomatic nocturnal enuresis (MNE), and to evaluate the long‐term results when these children grow into adolescence.

PATIENTS AND METHODS

The study included 34 children with refractory MNE; all were treated > 5 years earlier for their MNE using a combined stepwise approach, consisting of retention control training, oxybutynin and an enuresis alarm. Data were obtained on their enuretic state, night‐time voiding behaviour and bladder capacity, from a questionnaire and a voiding chart.

RESULTS

Before starting treatment, all patients had a bladder capacity that was too small for their age. After the combined stepwise approach, MNE improved in all patients and 24 (71%) were cured. Although the bladder capacity was increased to the age‐expected capacity in 26 (76%), most woke at night to void. Currently, at a mean of 7.7 years after the primary treatment, 28 (82%) of the patients are completely dry at night, of whom 15 (54%) arouse to void for 35% of the nights. Six patients (18%) still have some enuretic episodes. Only those who were dry after primary treatment and remained dry had a normal age‐expected increase in bladder capacity. For all others there was a decrease in age‐related bladder capacity.

CONCLUSIONS

In patients with refractory MNE, a combined stepwise approach improves and may even eliminate enuresis, but normal night‐time bladder behaviour in adolescence and adulthood is only achieved in some. Furthermore, about a fifth still have some enuretic episodes.
A simple procedure for isolating microgram quantities of biologically active bikunin from human urine
Authors: Yang Lizhu , Resnick Martin I. , Marengo Susan Ruth
Published: August 2005

OBJECTIVE

To report a simple, relatively rapid protocol to isolate biologically active bikunin from human urine using ion‐exchange‐trypsin affinity chromatography. Bikunin is a protease inhibitor which has been shown to play a role in various processes, including inhibition of calcium oxalate crystallization, the regulation of proliferation and modulation of carcinogenesis. The unavailability of the purified protein has hampered studies on bikunin's expanding role in these processes.

MATERIALS AND METHODS

Female human urine was dialysed (15 kDa threshold) and crudely fractionated with a double‐saturated ammonium sulphate precipitation. The first precipitation was with 35% saturated ammonium sulphate, and the supernatant was harvested, and the second with 90% saturated ammonium sulphate, and the precipitate collected. The protein mixture was then passed over Sepharose SP‐fast‐flow cation exchange and Sepharose Q‐fast‐flow anion exchange columns connected in series. The final purification was with a trypsin‐affinity column which selectively bound bikunin.

RESULTS

This procedure could recover 1 µg of bikunin per 2 mL of urine, and the final product was essentially free of contaminating inter‐α‐trypsin inhibitor heavy chains or bikunin‐heavy chain conjugates. Product purity was confirmed by two‐dimensional polyacrylamide gel electrophoresis combined with silver staining or Western blot. All isolations contained the 17 kDa minimally glycoslyated/sulphated form of bikunin and the 28 kDa form of bikunin. Some preparations also contained 33–48 kDa forms of bikunin. The protein cores of all three proteins were confirmed to be bikunin by mass spectrometry and Western blot. Harvested bikunin retained its trypsin inhibitory activity ( l‐benzoylarginine‐p‐nitroanilide assay). Preparations containing the 33–45 kDa form had two to three times more trypsin inhibitory activity than preparations without this band.

CONCLUSIONS

This novel ion exchange‐trypsin affinity chromatography protocol uses only two chromatographic steps. The product consists of three isomers of biologically active bikunin, free of contaminating heavy chains or bikunin‐heavy chain conjugates. The ready availability of purified bikunin should facilitate future studies of bikunin's emerging role in urolithiasis, proliferation and carcinogenesis.
Intracrystalline proteins and urolithiasis: a comparison of the protein content and ultrastructure of urinary calcium oxalate monohydrate and dihydrate crystals
Authors: Ryall Rosemary L. , Chauvet Magali C. , Grover Phulwinder K.
Published: August 2005

OBJECTIVE

To compare the ultrastructure and protein content, particularly prothrombin fragment 1 and osteopontin, of calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) crystals precipitated from human urine, and their susceptibility to proteolysis, to try to clarify the role of intracrystalline proteins in urolithiasis, as differences between these types of crystal may determine whether calcium oxalate crystals nucleated in urine progress to stone formation.

MATERIALS AND METHODS

Sodium dodecyl sulphate gel electrophoresis and Western blotting were used to analyse demineralized extracts of COM and/or COD crystals deposited from the same centrifuged and filtered urine (which contains abundant urinary proteins) by adjusting the calcium concentration to 2 and 7 mmol/L, respectively. Similar analyses were performed on COM and COD crystals deposited from ultrafiltered urine (which contains only proteins of < 10 kDa) and then incubated in centrifuged and filtered urine, as well as crystals generated in the presence of increasing concentrations of proteins derived from the organic matrix of urinary calcium oxalate crystals. Field‐emission scanning electron microscopy was used to assess effects of proteinase K and cathepsin D on internal and superficial crystal structure.

RESULTS

Osteopontin was undetectable in COM extracts, but clearly visible in COD. Prothrombin fragment 1 was abundant in COM, but present in COD in lesser amounts than osteopontin. The selectivity was also the same with crystals from ultrafiltered urine that were incubated in centrifuged and filtered urine: prothrombin fragment 1 binding was favoured by low calcium concentration, while osteopontin bound at higher levels. Scanning electron microscopy of COM and COD digested with proteinase K and cathepsin D revealed superficial and internal texture, as wells as surface erosion, in crystals from centrifuged and filtered urine, thus confirming the presence of intracrystalline proteins. Such features were absent from crystals precipitated from ultrafiltered urine.

CONCLUSION

Binding of osteopontin and prothrombin fragment 1 to calcium oxalate is dictated primarily by ambient calcium concentration. Each protein may inhibit urolithiasis by inhibiting crystallization of its preferred crystal habit, and by facilitating the intracellular disintegration and dissolution of crystals attached to and internalized by renal epithelial cells.
A tissue‐engineered suburethral sling in an animal model of stress urinary incontinence
Authors: Cannon Tracy W. , Sweeney Danielle D. , Conway Deidre A. , Kamo Izumi , Yoshimura Naoki , Sacks Michael , Chancellor Michael B.
Published: August 2005

OBJECTIVE

To create and evaluate the functional effects of a tissue‐engineered sling in an animal model of stress urinary incontinence (SUI).

MATERIALS AND METHODS

Twenty female Sprague‐Dawley rats were divided into four equal groups: a control group (C) had no intervention before the leak‐point pressure (LPP) was measured; a denervated group (D) had bilateral proximal sciatic nerve transection (PSNT) and periurethral dissection with no sling placed; group S had concomitant bilateral PSNT and a suburethral sling of small intestinal submucosa (SIS) placed; and group (M) had concomitant bilateral PSNT with implantation of a tissue‐engineered sling. The suburethral sling was placed via a transabdominal approach with the sling sutured to the pubic bone. Tissue‐engineered slings were prepared with muscle‐derived cells obtained via the pre‐plate technique and subsequently seeded for 2 weeks on a SIS scaffold. Suburethral slings were implanted 2 weeks before LPP testing, using the vertical‐tilt method.

RESULTS

Surgically placing a suburethral sling is feasible in the female rat, with few complications. LPPs from both sling groups (S and M) were not significantly different from untreated controls (C). The S, M and C groups all had significantly higher LPPs than group D. Importantly, no rat from either sling group (S and M) had signs of urinary retention.

CONCLUSIONS

Placing tissue‐engineered slings in an animal model of SUI resulted in LPP values that were not significantly different from those in untreated control or SIS (S) groups. These data show that incorporating muscle stem cells into SIS slings does not adversely alter the advantageous mechanical properties of the SIS sling in a model of SUI, and provide the basis for future functional studies of tissue‐engineered sling materials with long‐term retention.
Alterations in connexin expression in the bladder of patients with urge symptoms
Authors: Neuhaus Jochen , Pfeiffer Friederike , Wolburg Hartwig , Horn Lars‐Christian , Dorschner Wolfgang
Published: August 2005

OBJECTIVE

To compare the formation of gap junctions between detrusor smooth muscle cells in situ and the distribution of connexin (Cx)40, Cx43 and Cx45 expressions in bladder biopsies from a control group (with bladder tumour) and from patients with urge symptoms, as smooth muscle cells of the human detrusor muscle communicate via gap junctions and express several connexin subtypes, alterations of which may be involved in the causes of lower urinary tract symptoms.

MATERIALS AND METHODS

Connexin expression is prominent in myofibroblast‐like cells, supposedly involved in afferent signalling pathways of the bladder. Their strategic position directly beneath the urothelium suggests they are a link between urothelial ATP signalling during bladder filling and afferent Aδ‐fibre stimulation for co‐ordination of bladder tonus and initialization of the micturition reflex. Modification of their coupling characteristics may have profound impact on bladder sensation. Bladder tissue probes of patients undergoing cystectomy or transurethral tumour resection for bladder cancer were used as controls. Tissue samples from patients with severe idiopathic urge symptoms were taken for exclusion diagnostics of interstitial cystitis (IC) and carcinoma in situ. The formation of functional syncytia between detrusor smooth muscle cells were examined in dye‐coupling experiments by injecting with Lucifer Yellow. The morphology and structure of gap junctions were assessed by transmission electron microscopy and immunogold labelling of Cx43 and Cx45. The expression of connexin subtypes Cx40, Cx43 and Cx45 was compared by indirect immunofluorescence, and confocal laser scanning microscopy used for semiquantitative analysis.

RESULTS

There was dye coupling between smooth muscle cells of the detrusor in situ. Electron microscopy and immunogold labelling showed very small gap junctional plaques. These findings were confirmed by confocal immunofluorescence. Semiquantitative analyses showed significantly higher Cx43 expression in the detrusor muscle, and a tendency to higher Cx45 expression in the suburothelial layer associated with urge symptoms, whereas Cx40 expression was unaffected.

CONCLUSIONS

Smooth muscle cells of the human detrusor muscle are coupled by classical gap junctions, forming limited local functional syncytia. Both Cx43 and Cx45 are expressed at low levels in normal detrusor. Up‐regulation of Cx43 in patients with urge incontinence supports the possibility of functional changes in the syncytial properties of detrusor smooth muscle cells in this condition. In addition, the observed increase of Cx45 in the myofibroblast cell layer supports the idea that alterations in sensory signalling are also involved. Comparison with previous reports implies that the pathophysiology of urgency is distinct from that of the unstable bladder and other forms of incontinence.
A Tale of Two Towns: Social Structure, Integration and Crime in Rural New South Wales
Authors: Jobes Patrick C. , Donnermeyer Joseph F. , Barclay Elaine
Published: August 2005

This paper examines social factors that are associated with crime in two rural Australian communities with high proportions of Aboriginal people. It draws upon the theoretical contributions of Braithwaite (1989) to explain how levels of community integration and cohesion affect the presence of crime. Data for the case studies are derived from secondary statistics, surveys, observation and in‐depth interviews. Existing literature on crime in Australia emphasises the disproportionate representation of Aboriginal people within the criminal justice system. Yet, by comparing and contrasting the two communities, the analysis demonstrated that social structural and perceptual characteristics, rather than Indigenous status, account for high levels of crime in one community and low levels in the other. The analyses demonstrate that communities with high levels of social cohesion can ameliorate the affects of social disorganisation, division, and disadvantage in communities with high Aboriginal populations. It further demonstrates that rural crime is a complex and multi‐faceted phenomenon.
Visions in Agriculture
Authors: Gundelach Peter
Published: August 2005

Based on theories of social movements, this article is an analysis of the visions of the Presidium of the Danish Agricultural Council, the umbrella organisation for farmers' organisations in Denmark. The research is inspired by Alain Touraine's interventionist sociology. The research shows that the presidium was strongly committed to a productivist worldview, i.e. that the objective is to increase production, lower production costs and get as high prices as possible. The co‐operative history of Danish farming still played a role for the Presidium's worldview. They cherished the democratic procedures and institutions, but when there was an international merge the presidium did not wish to expand the privileges of membership to farmers in other countries. For Danish farmers the Presidium felt that the co‐operative way of organising was superior both democratically and economically. The analysis of the Presidium's narratives showed that it can clearly state a problematic situation ‐ the financial situation of the farmers ‐ but because it cannot attribute this injustice to specific groups it is unable to create a strong narrative about the opponents and hence about how the unfair situation might be improved.
Comparing the CCA Subspace Method to Pseudo Maximum Likelihood Methods in the case of No Exogenous Inputs
Authors: Bauer Dietmar
Published: August 2005

Abstract.  This paper deals with the CCA subspace algorithm proposed in Larimore [Proceeding of 1983 American Control Conference (1983) pp. 445–451], which constitutes an alternative to the classical criteria optimization based approach to the identification of linear dynamic models for a stationary process. Subspace algorithms for the estimation of linear models have been advocated mainly due to their numerical properties. A large variety of different subspace algorithms is known to provide strongly consistent and asymptotically normal estimates of the system under mild assumptions on the noise and the underlying true system. This paper shows that for certain versions of CCA described in the paper the estimates are asymptotically equivalent to pseudo maximum‐likelihood estimates in the sense that the difference in the estimators multiplied by the square root of the sample size converges to zero (in probability). Therefore these versions of CCA are asymptotically efficient for Gaussian innovations.
The Role of Consultation Clinics in Services for Children and Young People with Learning Disabilities and/or Autism
Authors: Cheseldine Sally , Manders Duncan , McGowan Clare
Published: August 2005

Background:  Consultation and supervision are familiar to many professionals, and their relevance to those working with children with learning disabilities and autism is discussed.

Method:  Consultation Clinics for Community Learning Disability Nurses and others were set up by a specialist Child and Adolescent Mental Health team servicing an area with a general population of 750,000. They were provided by a clinical psychologist and a psychiatrist, and data on their use were collected over a 16 month period.

Results:  There were differences in frequency of use between nurses based in more rural teams and those in city teams. The number of children discussed increased over time, and approximately half continued to be supported by the discussant, rather than being referred to the Tier 3 service.

Conclusions:  Suggestions are made as to the possible impact and benefits, with discussion also considering the role of professional responsibilities in consultative services.
Routine Outcome Measurement: A Survey of UK Child and Adolescent Mental Health Services
Authors: Johnston Craig , Gowers Simon
Published: August 2005

Background:  Research suggests that the routine measurement of treatment outcomes is a neglected area of clinical practice within mental health care settings. Still it is not clear to what extent such findings apply to child and adolescent mental health services (CAMHS). A cross‐sectional survey of UK CAMHS revealed that although quantitative clinical measures are commonly used within these services, there is little uniformity in the instruments utilised, and they rarely inform a system of routine outcome measurement. However, in general, respondents did not have a philosophical or scientific objection to the practice of routinely measuring outcomes, but rather felt that they lacked the necessary resources to facilitate such initiatives.
Psychiatrists’ Use of Melatonin with Children
Authors: Bramble David , Feehan Cathy
Published: August 2005

Background:  Melatonin is gaining popularity as a sedative agent with children. This study sought to characterise this practice more precisely as well as examine aspects of its safety and efficacy in order to develop treatment guidelines.

Method:  Postal surveys of two groups of psychiatrists: generic child psychiatrists and psychiatrists who regularly treat learning disabled children.

Results:  Both groups (all of the specialists and 81% of the non‐specialists) reported regular but not frequent use of melatonin in their usual practice, mostly for night‐settling sleep problems refractory to behavioural modification strategies, commonly in the context of neurodevelopmental disability (especially autism). Treatment was described as being ‘usually successful’ and side‐effects were highly infrequent and mild in nature. Variations in most prescribing practices were identified (dosage, timing).

Conclusions:  Melatonin appears to represent a useful and relatively safe drug when used in specific circumstances; however, the evidence‐base underpinning its use, particularly over the long‐term, remains modest. Thus caution and clinical audit of practice is required.
Dementia and Alzheimer's Disease Incidence in Relationship to Cardiovascular Disease in the Cardiovascular Health Study Cohort
Authors: Newman Anne B. , Fitzpatrick Annette L. , Lopez Oscar , Jackson Sharon , Lyketsos Constantine , Jagust William , Ives Diane , DeKosky Steven T. , Kuller Lewis H.
Published: August 2005

Objectives: To determine whether coronary artery disease, peripheral arterial disease (PAD), or noninvasive markers of cardiovascular disease (CVD) predict the onset of dementia and Alzheimer's disease (AD).

Design: Longitudinal cohort study.

Setting: Four U.S. communities.

Participants: Men and women (N=3,602) with a brain magnetic resonance imaging (MRI) scan but no dementia were followed for 5.4 years. Participants with stroke were excluded.

Measurements: Neurologists and psychiatrists classified incident cases of dementia and subtype using neuropsychological tests, examination, medical records and informant interviews. CVD was defined at the time of the MRI scan. Noninvasive tests of CVD were assessed within 1 year of the MRI. Apolipoprotein E allele status, age, race, sex, education, Mini‐Mental State Examination score, and income were assessed as potential confounders.

Results: The incidence of dementia was higher in those with prevalent CVD, particularly in the subgroup with PAD. The rate of AD was 34.4 per 1,000 person‐years for those with a history of CVD, versus 22.2 per 1,000 person‐years without a history of CVD (adjusted hazard ratio (HR)=1.3, 95% confidence interval (CI)=1.0–1.7). Rates of AD were highest in those with PAD (57.4 vs 23.7 per 100 person‐years, adjusted HR=2.4, 95% CI=1.4–4.2). Results were similar with further exclusion of those with vascular dementia from the AD group. A gradient of increasing risk was noted with the extent of vascular disease.

Conclusion: Older adults with CVD other than stroke had a higher risk of dementia and AD than did those without CVD. The risk was highest in people with PAD, suggesting that extensive peripheral atherosclerosis is a risk factor for AD.
Relationship Between Patient Age and Duration of Physician Visit in Ambulatory Setting: Does One Size Fit All?
Authors: Lo Agnes , Ryder Kathryn , Shorr Ronald I.
Published: August 2005

Objectives: To determine whether patient age, the presence of comorbid illness, and the number of prescribed medications influence the duration of a physician visit in an ambulatory care setting.

Design: A cross‐sectional study of ambulatory care visits made by adults aged 45 and older to primary care physicians.

Setting: A probability sample of outpatient follow‐up visits in the United States using the National Ambulatory Medical Care Survey (NAMCS) 2002 database.

Participants: Of 28,738 physician visits in the 2002 NAMCS data set, there were 3,819 visits by adults aged 45 and older included in this study for analysis.

Measurements: The primary endpoint was the time that a physician spent with a patient at each visit. Covariates included for analyses were patient characteristics, physician characteristics, visit characteristics, and source of payment. Visit characteristics, including the number of diagnoses and the number of prescribed medications, the major diagnoses, and the therapeutic class of prescribed medications, were compared for different age groups (45–64, 65–74, and ≥75) to determine the complexity of the patient's medical conditions. Endpoint estimates were computed by age group and were also estimated based on study covariates using univariate and multivariate linear regression.

Results: The mean time±standard deviation spent with a physician was 17.9±8.5 minutes. There were no differences in the duration of visits between the age groups before or after adjustment for patient covariates. Patients aged 75 and older had more comorbid illness and were prescribed more medications than patients aged 45 to 64 and 65 to 74 (P<.001). Patients aged 75 and older were also prescribed more medications that require specific monitoring and counseling (warfarin, digoxin, angiotensin‐converting enzyme inhibitors, diuretics, and levothyroxine) than were patients in other age groups (P<.001). Hypertension, coronary artery disease, atrial fibrillation, congestive heart failure, cerebrovascular disease, and transient ischemic attack were more common in patients aged 75 and older than in other age groups (P<.001). Despite these differences, there were no differences in unadjusted or adjusted duration of physician visit between the age groups.

Conclusion: Although patients aged 75 and older had more medical conditions and were at higher risk for drug‐related problems than younger patients, the duration of physician visits was similar across the age groups. These findings suggest that elderly patients may require a multidisciplinary approach to optimize patient care in the ambulatory setting.
Mobility Limitations in the Medicare Population: Prevalence and Sociodemographic and Clinical Correlates
Authors: Shumway‐Cook Anne , Ciol Marcia A. , Yorkston Kathryn M. , Hoffman Jeanne M. , Chan Leighton
Published: August 2005

Objectives: To examine the prevalence of and clinical markers associated with mobility limitations in Medicare Current Beneficiary Community Survey (MCBS) respondents.

Design: Cross‐sectional analysis of a community survey.

Setting: Community.

Participants: Twelve thousand seven hundred sixty‐nine respondents from the 2001 MCBS, aged 65 and older.

Measurements: Four questions from the MCBS were used to create four levels of mobility limitation: none, mild, moderate, and severe. Sampling weights were used to calculate estimates of means and proportions of the entire Medicare population for each mobility limitation category. A polytomous logistic regression analysis was used to model the association between four levels of mobility limitation and sociodemographic and clinical variables.

Results: Prevalence of mobility limitations ranged from 9.5 million (mild) to 1.2 million (severe). Increasing severity of mobility limitation was associated with older age, being female, reporting fair or poor health, being overweight, smoking, having a greater number of comorbidities, having an annual income below $25,000, having less than a high school education, being unmarried, and living with others.

Conclusion: National prevalence estimates suggest that functional mobility limitation is a significant problem for many older adults and is associated with some potentially modifiable characteristics.
Inequities in Higher Education: Issues and Promising Practices in a World Ambivalent about Affirmative Action
Authors: Niemann Yolanda Flores , Maruyama Geoffrey
Published: August 2005

The U.S. Supreme Court ruled on the legality of race‐based affirmative action at universities in 2003. Although the decisions affirmed the legality of considering race in college admissions decisions, their long‐term effects are not entirely clear. They neither resolved conflicts nor solved problems affirmative action was intended to address, namely, disparities in educational outcomes between Whites and ethnic/racial minorities. Although disparities have diminished since 1965, policies and practices to sustain and further increase diversity in higher education without affirmative action are needed. This article provides historical and conceptual grounding for this JSI issue, which examines approaches for attaining campus diversity. Collectively, the issue provides approaches for increasing diversity as well as strategies for managing and benefiting from diversity in postsecondary environments.
The Role of Pre‐collegiate Partnership Programs in Environments Ambivalent about Affirmative Action: Reflections and Outcomes from an Early Implementation
Authors: Maruyama Geoffrey , Burke Maggie , Mariani Carlos
Published: August 2005

Preparing underrepresented students for college success though pre‐collegiate partnership programs is one alternative to affirmative action programs. This article describes the Multicultural Excellence Program (MEP), a partnership program between an urban school district and 22 four‐year higher education institutions. MEP, begun in 1987, targets 7th–12th‐grade students from groups historically underrepresented in higher education. It helps them plan how to prepare themselves for continuing on to a four‐year college. Analyses evaluating program effectiveness examined outcomes of over 4,000 secondary students and 243 college students. Despite substantial turnover, particularly at transition points, MEP has been very successful in enrolling its high school graduates immediately in four‐year colleges. Although many MEP students have thrived in college, a smaller proportion has struggled.
The Next Generation of Diversity and Intergroup Relations Research
Authors: Hurtado Sylvia
Published: August 2005

Recent court decisions and cultural shifts have led to a new focus for work on equity and equality of outcomes in educational settings. This article reviews the contributions of recent diversity studies and then focuses on a longitudinal study of 4,403 college students attending nine public universities. Results show that student interaction with diverse peers during college results in changes in student cognitive, social, and democratic outcomes by the second year of college. Campus efforts to provide opportunities for students to learn about diverse groups inside and outside the classroom have an appreciable impact on students.
Understanding and Addressing Contemporary Racism: From Aversive Racism to the Common Ingroup Identity Model
Authors: Gaertner Samuel L. , Dovidio John F.
Published: August 2005

This article describes our collaborative research on aversive racism and a strategy we developed to combat it, the Common Ingroup Identity Model. In addition, we reveal some details about our personal and professional relationship in pursuit of our scientific agenda. We begin by discussing evidence for the existence of aversive racism, a subtle, unintentional form bias that can have pernicious effects. Then we review research concerning how a common ingroup identity can combat aversive racism by redirecting the forces of social categorization and social identity, such that “Us” and “Them” are regarded as “We.” We conclude with a brief discussion of where we may look next for clues toward helping to achieve a fairer, more just society.
Bachmann's Bundle: Does It Play a Role in Atrial Fibrillation?
Authors: KHAJA AZAMUDDIN , FLAKER GREG
Published: August 2005

Background: Cardiac anatomists have known the presence of a group of specialized fibers connecting the right and left atrium for years. However, only recently have clinical cardiologists come to recognize the potential importance of this specialized conduction system. Anatomical and microscopic studies have shown that the Bachmann's bundle (BB) represents a distinct structure similar to the atrio‐ventricular node and the His‐Purkinje conduction system but without any insulating tissue.

Results: BB cells have specialized electrophysiological properties like supernormal excitability and faster longitudinal conduction that can facilitate more rapid impulse transmission compared to the normal atrial tissue. Experimental blockage of this pathway causes prolongation and widening of the P wave, which is associated with an increased incidence of atrial fibrillation. Atrial pacing is effective in reducing the incidence of atrial fibrillation by preventing bradycardia, synchronizing the atria, limiting anisotropy and reducing the dispersion of refractoriness. Various animal and human studies have shown pacing near the right atrial insertion of BB to have a beneficial effect in patients with interatrial conduction delay and atrial tachyarrhythmias. This mode of atrial septal pacing is convenient, safe, reliable, and clinically as effective as multisite pacing.

Conclusion: This article is an effort to define the special properties of BB and its possible role in prevention of atrial fibrillation by permanent pacemakers.
Acquired Arteriovenous Fistula and Chronic Occlusion of the Left Anterior Descending Coronary Artery in a Patient with Previous Ablation of a Left‐Sided Accessory Pathway
Authors: WIECZOREK MARCUS , BRAUN PETER , SCHOELS WOLFGANG
Published: August 2005

Endocardial catheter ablation of accessory pathways is now considered as therapy of first choice in symptomatic patients. Success rates depend on the location of the accessory pathway itself and the operators experience in catheter ablation procedures. In patients with a left‐sided pathway the retrograde transaortic catheter approach is used routinely in most centers. Besides occasional injuries of the vessels used for catheter placement and perforation of the cardiac chambers, there have been only a few case reports in the literature reporting rare procedure‐specific complications such as catheter entrapment within the mitral valve apparatus and occlusion of the left circumflex coronary artery. We report a case of primary successful endocardial catheter ablation of a left lateral accessory pathway in a patient with normal coronary arteries at that time. Many years later progressive deterioration of systolic left ventricular function was observed. Coronary angiography revealed occlusion of LAD next to a arteriovenous (AV) fistula between the LAD and the anterior right ventricle.
Endocardial catheter ablation was the only known cardiac manipulation in this patient raising the possibility that unintended catheter manipulations within the LAD had led to this rare and severe complication.
Impact of Duration of Cryothermal Application on Clinical Efficacy of Pulmonary Vein Isolation Using Transvenous Cryoablation
Authors: TSE HUNG‐FAT , LAU CHU‐PAK
Published: August 2005

Background: Recent studies have demonstrated that transvenous cryoablation is a safe and feasible method for pulmonary vein (PV) isolation for treatment of atrial fibrillation (AF). However, this technique is limited by a much longer ablation time than conventional radiofrequency ablation. The aim of this study was to determine the effect of duration of cryoablation application with double freeze‐thaw cycles on clinical efficacy for PV isolation for treatment of AF.

Materials and Results: We compared the clinical efficacy and procedural time of cryoablation (CryoCorTM, San Diego, CA, USA) for segmental PV isolation in 30 patients (mean age 51 ± 13, 20 men) with paroxysmal AF using either double 5‐minute (n = 15) or double 2.5‐minute (n = 15) freeze‐thaw cycle delivered with a 10 F deflectable transvenous catheter. Clinical recurrence of AF and the occurrence of PV stenosis as determined by computer tomography of the thorax were performed at 3‐ and 12‐month follow‐up. Acute successful electrical isolation of PV was achieved with cryoablation in 96 of 98 (98%) targeted PVs in 30 patients (mean: 3.2 ± 0.8 PVs per patient). There were no significant differences between the baseline characteristics, the number of PV isolated per patient, the total number and percentage of effective cryoablation and the acute clinical efficacy between using double 5‐minute and double 2.5‐minute freezes (P > 0.05). However, the fluoroscopy time (107 ± 43 vs 138 ± 113 minutes, P = 0.06) and the procedural time (360 ± 113 vs 510 ± 115 minutes, P = 0.01) of using double 2.5‐minute freezes was reduced by ∼30% compared with double 5‐minute freezes. At a mean of 20 ± 8 month follow‐up, there was no significant difference in the chronic clinical efficacy of cryoablation in terms of freedom from AF in the absence of antiarrhythmic drug therapy between using double 5‐minute (6/15, 40%) and double 2.5‐minute freezes (7/15, 46%, P = 0.98).

Conclusion: As compared with double 5‐minute freeze, the use of a shorter double 2.5‐minute freeze protocol significantly reduces the procedural time without affecting the acute and long‐term clinical efficacy of cryoablation to isolate PV for treatment of AF.
Far‐Field R‐Wave Reduction with a Novel Lead Design: Experimental and Human Results
Authors: DE VOOGT WILLEM , VAN HEMEL NORBERT , WILLEMS ALBERT , VISSER JAAP , CHITRE YOUGANDH , BORNZIN GENE , HELLAND JOHN
Published: August 2005

Introduction: The purpose of this study was to examine a bipolar screw‐in lead (NL), specially designed to reduce unwanted far‐field R‐wave (FFRW) signal detection in an acute human setting. The results were compared with animal experiments.

Methods: The newly designed lead with a center‐to‐center distance between the anode and cathode electrodes of 3.23 mm, corresponding to an inter‐electrode spacing of 1.1 mm was implanted in nine canines with a follow‐up of 6 months. Sensing of P waves, FFRW signals, pacing threshold, and impedance was measured at regular intervals. As a result of the positive outcome with the animal study, an acute human experiment was performed. In patients scheduled for conventional dual chamber pacemaker implantation, the NL was compared to a Tendril® Model 1388T bipolar screw‐in lead (St. Jude Medical, CRMD, Sylmar, CA).

Results: Utilizing a tip‐to‐ring distance of 1.1 mm, the optimum P wave to FFRW ratio was found in animal experiments. In the acute human tests in 15 patients, the mean P‐wave voltage of the 1388T lead of 3.30 ± 1.54 mV was slightly larger than that of the NL, at 2.55 ± 1.11 mV, but did not differ significantly (P = 0.13). The FFRW voltage of the 1388T lead was 0.62 ± 0.37 mV and was significantly greater from that of the NL, at 0.10 ± 0.08 mV (P < 0.0001). Pacing thresholds and pacing impedances were comparable.

Conclusion: Animal testing results were reproducible in the acute human test setting. The lead reduced the paced FFRW signal amplitudes significantly, allowing for high atrial sensitivity settings but without sensing the FFRW. A robust P‐wave signal could be retained.
Unusual QRS Morphology on ECG: A Rare Condition and an Interesting Response to Pacing
Authors: GULA LORNE J. , ECKART ROBERT E. , KLEIN GEORGE J. , PERALTA ADELQUI
Published: August 2005

We present the interesting case of a young man with borderline wide QRS complexes noted on electrocardiogram (ECG). The diagnosis of an unusual form of preexcitation was reached using observations from intracardiac tracings at electrophysiology study. Atrial pacing consistently resulted in further widening of the first conducted QRS complex, and the physiology underlying this unusual finding is explored.
Angioplasty Facilitated Permanent Pacing in de Novo Superior Vena Cava Obstruction
Authors: PRASAN ANANTH M. , GIRARDI PETER , GLENN DEREK , RAMSAY DAVID R.
Published: August 2005

The finding of complete occlusion of the superior venal cava during the performance of cardiac pacing is rare. We report a case where performance of angioplasty aided the successful completion of permanent pacemaker implantation.
Temporal Relationship of Implantable Cardioverter Defibrillator Discharges and Environmental Physical Activity
Authors: STOUPEL ELIYAH , KUSNIEC JAIRO , MAZUR ALEXANDER , ZABARSKY RONIT , GOLOVCHINER GREGORY , ABRAMSON EVGENY , STRASBERG BORIS , BATTLER ALEXANDER
Published: August 2005

Background: Studies by our group have shown an inverse relationship between sudden death and cardiac rhythm disturbances and environmental levels of geomagnetic activity (GMA). The aim of this study was to use the precise data provided by automatic implantable cardioverter defibrillators (ICDs) regarding the onset of ventricular fibrillation and ventricular tachycardia to link these events to GMA level.

Patients and Methods: The study group included 25 patients (22 men; 22 with ischemic cardiomyopathy) aged 28–81 years in whom an ICD had been implanted between 1995 and 2004. Patients were referred to the cardiac intensive care unit after each event that induced one or more discharges. The number of events and the day on which they occurred were recorded. Data on GMA and other cosmophysical parameters were obtained from the U.S. National Geophysical and Space Service Centers and the Russian Academy of Sciences. GMA levels, graded from I (quiet) to IV (stormy) in the middle latitutes, were recorded for 1974–2003 (10,954 days) and for each day on which an ICD discharge occurred.

Results: A total of 402 discharges were recorded on 137 days during the study period. Forty‐six percent of the discharges took place on days of GMA I, compared with 38%– II, 13%– III, and 3%– IV. The daily distribution of GMA was as follows: level I – 35.2%, II – 37.3%, III – 21.86%, IV – 5.61%. Comparison of ICD discharge days and actual multiyear levels of GMA (in percent) yielded a ratio of 1.326 for GMA I, 1.076 – II, 0.459 – III, 0.390 – IV. There was a significant inverse correlation between GMA level and number of discharges (r =−0.97, P = 0.03) and days of treatment (r =−0.96, P = 0.039), and a significant difference between ICD discharges on days of GMA I and GMA II–IV (χ2= 5.05, P = 0.02).

Conclusion: The higher number of ICD discharges on days of lowest GMA may be explained by a possible antiarrhythmic effect of GMA. Environmental arrhythmogenic factors that act inversely to GMA may be activated at times of low GMA.
Predation risk allocation or direct vigilance response in the predator interaction between perch (Perca fluviatilis L.) and pike (Esox lucius L.)?
Authors: Vainikka A. , Jokelainen T. , Kortet R. , Ylönen H.
Published: August 2005

Abstract –  Predation risk allocation hypothesis predicts that a prey's response to predator depends on prey's previous experience on predator. Here we tested whether the group of three perch respond differentially to pike, predator of perch, depending on the timing of high constant (HC) and high unpredictable (HU) risk periods within low constant risk periods in short‐term (10 h) experiments, and whether the response is stronger during a HU risk period than during a HC risk period. Perch clearly erected the dorsal fin in response to predation risk treatments (pike odour only, odour and visible pike). Decrease in activity and increase in shoaling behaviour were observed mainly during high risk periods. However, the perch's responses to pike did not differ statistically between periods of various levels of predation risk or depending on the timing of high risk situations within constant low risk periods, and thus, suggesting that perch respond mainly to changes in the current predation risk.
Lipid energy reserves influence life‐history decision of Atlantic salmon (Salmo salar) and brown trout (S. trutta) in fresh water
Authors: Jonsson B. , Jonsson N.
Published: August 2005

Abstract –  Lipid density appears to influence life‐history decisions in salmonid fishes. This study shows that parr and smolts of anadromous Atlantic salmon from a south Norwegian river have on average between 30 and 40% higher energy level than corresponding brown trout in spring and summer, which may explain differences in life‐history traits between the two species. The higher energy density of young salmon was chiefly due to a 1.8 times higher lipid density in parr and 2.4 times higher lipid density in smolts. The difference was smaller among immature parr in the autumn, with only 1.4 times higher lipid density in salmon than trout. The reason for the decreased difference was probably that the more energy rich salmon parr had attained maturity at the time. Among mature male parr, the somatic energy density was approximately 10% higher in trout than salmon. However, the gonadal energy content was more than twice as high in salmon than in trout. The higher somatic energy allocation in parr of Atlantic salmon probably influences protein growth of the two species in fresh water, and increases the ability of salmon relative to trout to undertake long distance feeding migrations and make large investments in reproduction.
Does embeddedness affect growth performance in juvenile salmonids? An experimental study in brown trout, Salmo trutta L.
Authors: Bolliet V. , Bardonnet A. , Jarry M. , Vignes J. C. , Gaudin P.
Published: August 2005

Abstract –  The effect of an embedded substratum on emigration and growth in juvenile brown trout was investigated in an artificial stream with sand added to produce sections of embedded or nonembedded substratum. Fish were allowed to leave the sections and were caught daily in a downstream trap. After catching and counting, fish were put back in their original section in order to keep the same amount of fish. Captures were high only on the first days after fish release. During the first 6 days after fish release, downstream‐moving fish were more numerous in the embedded than in the nonembedded sections. The embedded substratum significantly decreased the final mean body weight and condition factor and increased heterogeneity in fish size. We suggest that a decrease in the habitat carrying capacity for juveniles could be the main factor explaining this result.
Effects of within‐patch habitat structure and variation on fish assemblage characteristics in the Bernecei stream, Hungary
Authors: Erős T. , Grossman G. D.
Published: August 2005

Abstract –  Over a 3‐year period we examined variability in physical habitat structure and species richness, abundance and assemblage composition of fishes in 13 habitat patches in the Bernecei stream, Hungary. Principal component analysis of habitat structure data from patches elucidated a riffle‐run‐pool habitat gradient across patches. Temporal habitat variability increased significantly from riffle to pool patches. Fish assemblage characteristics displayed relatively continuous change over the habitat gradient and were relatively stable within patches. Assemblage structure properties (e.g., species richness) displayed different responses to the habitat gradient and to within‐patch habitat variability. In general, pool patches had more diverse assemblages and greater within‐patch assemblage variability than riffle patches. However, within‐patch dynamics were largely determined by the population dynamics of a habitat generalist (i.e., minnow). Broad scale environmental variability (i.e., a catastrophic 100‐year flood) also appeared to affect within‐patch fish assemblage characteristics. Our results demonstrate that fish assemblage structure is influenced by physical variability (i.e., both floods and spatio‐temporal habitat variability) within the Bernecei stream.