bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of aerosols generated in a steel processing factory
Authors: Garimella Sitaram , Deo Ravin N.
Published: March 2008

The levels of total suspended particulates (TSP) within the complex of a steel factory (Fletcher Pacific Steel Fiji) have been investigated through high volume air sampling. The levels of TSP inside and outside (in the ambient environment) the factory has been found to be in the range of 121-339 and 33-80 μg m-3 respectively. The levels inside the factory exceed the WHO guideline by a factor of 2-4. The management of the factory was very proactive to determine the air quality for records and to safeguard the health and safety of all the employees, contractors, and visitors. At the request of the factory, the exposed filters were analysed by neutron activation and gamma-ray spectroscopy techniques and the results are presented.
Technology and innovation in the psychosocial treatment of methamphetamine use, risk and dependence
Authors: KAY‐LAMBKIN FRANCES J.
Published: March 2008

Issues. The dramatic increase in methamphetamine use has led to the urgent need for high‐quality, effective treatments and management strategies for methamphetamine use problems to be developed and disseminated. Although some evidence exists for the use of psychological, pharmacological and other approaches to treatment for problematic methamphetamine use, other evidence suggests that many methamphetamine users do not access these treatment options due to a range of individual and service‐level barriers. Approach. A review of available research literature was undertaken to identify treatment strategies for methamphetamine users, which overcome the problems associated with treatment access for this important target group and involve technological and other innovative approaches. Key Findings. Several approaches to addressing problematic methamphetamine use have been suggested, including assertive engagement strategies, flexibility in the provision of treatment and retention strategies and use of a multi‐focused intervention package, such as stepped care, perhaps including new technologies as alternatives or supplements to face‐to‐face‐delivered treatments. No research currently exists to examine the possible benefit of these strategies for people with methamphetamine use problems. Implications. The use of stepped‐care intervention packages has the potential to address many of the current challenges faced by both clinicians and clients in treating methamphetamine use problems. Conclusions. Although promising, these approaches require further attention and research effort, particularly among the specific group of methamphetamine users.
Trends in methamphetamine use in young injection drug users in San Francisco from 1998 to 2004: the UFO Study
Authors: INGLEZ‐DIAS ALINE , HAHN JUDITH A. , LUM PAULA J. , EVANS JENNIFER , DAVIDSON PETER , PAGE‐SHAFER KIMBERLY
Published: March 2008

Aims. To describe temporal trends in methamphetamine use among young injection drug users (IDU) in San Francisco. Design and Methods. Secondary analysis of cross‐sectional baseline data collected for a longitudinal study of young IDU from 1998 to 2004. Participants were 1445 young IDU (<30 years old) who reported injection in the previous month, English‐speaking, and recruited by street outreach methods. We examined trends for: lifetime (ever) and recent (30‐day) methamphetamine use, including injected and non‐injected, and by age group and sexual risk behaviour [men who have sex with men injecting drug users (MSM‐IDU), male IDU (non‐MSM) and female IDU]. Results. In 1998, 1999, 2000, 2001, 2003 and 2004 we interviewed 237, 276, 431, 310, 147 and 44 participants, respectively. Overall, median age was 22 years [interquartile range (IQR) 20–25], 30.3% were women and median duration of injecting was 4.4 years (IQR 2–7). Prevalence of methamphetamine use was high, with 50.1% reporting recent injection, but overall there were no temporal increases in reported ‘ever’ injected use. Recent methamphetamine injection (past 30 days) increased significantly, and peaked at 60% in 2003. MSM‐IDU had higher methamphetamine injection ever (92.3%) and recently (59.5%) compared to heterosexual male (non‐MSM) IDU (81.6% and 47.3%, respectively) and to female IDU (78.4% and 46.1%, respectively). Conclusions. Despite reports of ubiquitous increases in methamphetamine use, there were no significant increases in 6 years in ever injecting methamphetamine overall among young IDU. MSM‐IDU who reported the highest methamphetamine use overall reported some increases in recent injected use. The methamphetamine ‘epidemic’ was probably under way among young IDU earlier than other populations.
The rise of methamphetamine in Southeast and East Asia
Authors: McKETIN REBECCA , KOZEL NICHOLAS , DOUGLAS JEREMY , ALI ROBERT , VICKNASINGAM BALASINGAM , LUND JOHANNES , LI JIH‐HENG
Published: March 2008

Introduction and Aims. Southeast and East Asia has become a global hub for methamphetamine production and trafficking over the past decade. This paper describes the rise of methamphetamine supply and to what extent use of the drug is occurring in the region. Method and Design. The current review uses data collected through the Drug Abuse Information Network for Asia and the Pacific (DAINAP) and other available sources to analyse retrospectively methamphetamine trends within Southeast and East Asia. Results. Southeast and East Asia has experienced a methamphetamine epidemic in the past decade which began around 1997 and peaked in 2000–2001. While the situation has since stabilised in many countries, methamphetamine trafficking and use are still increasing in parts of the Mekong region and there is evidence of large‐scale manufacture in Cambodia, Indonesia, Malaysia and the Philippines. Methamphetamine is typically smoked or ingested, but injection of the drug is apparent. Conclusion. While the peak of the methamphetamine epidemic has passed in parts of Southeast and East Asia, attention is needed to minimise the potential consequences of spreading methamphetamine production, trafficking and use in the Mekong region and in the peninsular and archipelago of Southeast Asia.
Object carrying as socio-sexual display in an aquatic mammal
Authors: Martin A.R , da Silva V.M.F , Rothery P
Published: March 2008

Amazon river dolphins or botos (
Inia geoffrensis
Blainville) were observed carrying objects in 221 social groups over a 3-year study period. Sticks, branches and clumps of grass were taken from the water surface and often repeatedly thrashed or thrown. Lumps of hard clay were collected from the river bed and held in the mouth while the carrier rose slowly above the surface and submerged again. Carriers were predominantly adult males and less often subadult males. Adult females and young dolphins rarely carried objects. Groups of dolphins in which object carrying occurred were differentially large and comprised a greater proportion of adult males and adult females. Aggression, mostly between adult males, was significantly associated with object carrying. The behaviour occurred year-round, with peaks in March and July. A plausible explanation of the results is that object carrying by adult males is aimed at females and is stimulated by the number of females in the group, while aggression is targeted at adult males and is stimulated by object carrying in the group. We infer that object carrying in this sexually dimorphic species is socio-sexual display. It is either of ancient origin or has evolved independently in several geographically isolated populations.
Necessary and sufficient conditions for the two-point phase probability function of two-phase random media
Authors: Quintanilla John A
Published: March 2008

Constructing realizations of random media with a specified two-point phase probability function
S
2
has attracted considerable attention in the recent literature. However, little is known about conditions under which a prescribed
S
2
is realizable. The only known necessary and sufficient condition, due to McMillan, involves a class of square matrices, called corner-positive matrices, about which almost nothing is known except their definition. As a result, McMillan's theorem has gone mostly unused in the literature for over 50 years. In this paper, we present a general decomposition formula for corner-positive matrices, which allows McMillan's theorem to be written in a significantly more tractable and testable form. We also connect McMillan's theorem with many known but heretofore unrelated necessary conditions on
S
2
, extending many of these conditions.
Residual reproductive value and male mating success: older males do better
Authors: Fischer Klaus , Perlick Jana , Galetz Tobias
Published: March 2008

Evolution via sexual selection has traditionally been viewed as isolated from life-history constraints. As additionally reproductive resource allocation in males is underexplored, it is rather unclear how life-history factors have shaped lifetime investment into male sexually selected traits. Against this background, we here investigate male butterfly mating success in relation to age, nutritional status, assay condition and wing damage. As predicted, based on a low residual reproductive value, older males had a considerably higher mating success than younger males. Comparisons between virgin and once-mated males suggest that this pattern is related to age
per se
rather than differential ratings of the resource receptive female. We found no evidence for male body size or condition being important, supporting the notion that in weaponless animals intrinsic motivation is more important for mating success than the differences in physical properties (such as body size or condition). Flight cage experiments suggest that such differences in motivation may be masked under more natural conditions, where flight performance, having a clear impact on mating success (as evidenced by wing manipulation experiments), is likely to be crucial. We conclude that the life-history perspective is a fruitful one for gaining a better understanding of the evolution of sexually selected characters and the predictions derived from contest theory do also apply to male mating success.
Generation time and effective population size in Polar Eskimos
Authors: Matsumura Shuichi , Forster Peter
Published: March 2008

North Greenland Polar Eskimos are the only hunter–gatherer population, to our knowledge, who can offer precise genealogical records spanning several generations. This is the first report from Eskimos on two key parameters in population genetics, namely, generation time (T) and effective population size (Ne). The average mother–daughter and father–son intervals were 27 and 32 years, respectively, roughly similar to the previously published generation times obtained from recent agricultural societies across the world. To gain an insight for the generation time in our distant ancestors, we calculated maternal generation time for two wild chimpanzee populations. We also provide the first comparison among three distinct approaches (genealogy, variance and life table methods) for calculatingNe, which resulted in slightly differing values for the Eskimos. The ratio of the effective to the census population size is estimated as 0.6–0.7 for autosomal and X-chromosomal DNA, 0.7–0.9 for mitochondrial DNA and 0.5 for Y-chromosomal DNA. A simulation of alleles along the genealogy suggested that Y-chromosomal DNA may drift a little faster than mitochondrial DNA in this population, in contrast to agricultural Icelanders. Our values will be useful not only in prehistoric population inference but also in understanding the shaping of our genome today.
The dynamics of acute malaria infections. I. Effect of the parasite's red blood cell preference
Authors: Antia Rustom , Yates Andrew , de Roode Jacobus C
Published: March 2008

What determines the dynamics of parasite and anaemia during acute primary malaria infections? Why do some strains of malaria reach higher densities and cause greater anaemia than others? The conventional view is that the fastest replicating parasites reach the highest densities and cause the greatest loss of red blood cells (RBCs). Other current hypotheses suggest that the maximum parasite density is achieved by strains that either elicit the weakest immune responses or infect the youngest RBCs (reticulocytes). Yet another hypothesis is a simple resource limitation model where the peak parasite density and the maximum anaemia (percentage loss of RBCs) during the acute phase of infection equal the fraction of RBCs that the malaria parasite can infect. We discriminate between these hypotheses by developing a mathematical model of acute malaria infections and confronting it with experimental data from the rodent malaria parasite
Plasmodium chabaudi
. We show that the resource limitation model can explain the initial dynamics of infection of mice with different strains of this parasite. We further test the model by showing that without modification it closely reproduces the dynamics of competing strains in mixed infections of mice with these strains of
P. chabaudi
. Our results suggest that a simple resource limitation is capable of capturing the basic features of the dynamics of both parasite and RBC loss during acute malaria infections of mice with
P. chabaudi
, suggesting that it might be worth exploring if similar results might hold for other acute malaria infections, including those of humans.
Directional dispersal between mid‐ocean ridges: deep‐ocean circulation and gene flow in Ridgeia piscesae
Authors: YOUNG C. R. , FUJIO S. , VRIJENHOEK R. C.
Published: March 2008

This study examined relationships between bathymetrically induced deep‐ocean currents and the dispersal of the hydrothermal vent tubeworm Ridgeia piscesae along the northeast Pacific ridge system. A robust diagnostic model of deep‐ocean circulation in this region predicted strong southeasterly currents following contours of the Blanco Transform Fault, a 450‐km lateral offset that separates the Gorda and Juan de Fuca ridge systems. Such currents should facilitate the southward dispersal of R. piscesae larvae. Immigration rates for populations north and south of the Blanco Transform Fault were estimated from molecular population genetic data. Mitochondrial DNA evidence revealed population subdivision across the Blanco Transform Fault, and a strong directional bias in gene flow that was consistent with predictions of the circulation model. The distribution of mitochondrial diversity between the northern and southern populations of R. piscesae suggests that the Gorda Ridge tubeworms have maintained larger effective population sizes than the northern populations, a pattern that also exists in co‐occurring limpets. Together, these data suggest that the northern vent fields may experience a higher frequency of habitat turnover and consequently more rapid losses of genetic diversity.
Characterization of resistance gene analogs with a nucleotide binding site isolated from a triploid white poplar
Authors: Zhang Q. , Zhang Z.‐Y. , Lin S.‐Z. , Zheng H.‐Q. , Lin Y.‐Z. , An X.‐M. , Li Y. , Li H.‐X.
Published: March 2008

The majority of cloned plant disease resistance genes (R genes) encode a nucleotide binding site (NBS) and a leucine‐rich repeat (LRR) domain. In this study, to better understand the R genes in white poplar, 59 resistance gene analogues (RGAs) were identified from a triploid white poplar [(Populus tomentosa × Populus bolleana) × P. tomentosa], based on conserved NBS regions. The 59 RGAs were phylogenetically classified into 10 subfamilies, and 54 RGAs with open‐reading frames (ORFs) were further grouped into two classes, toll and interleukin‐1 receptor (TIR) and non‐TIR. BLAST searches with reference to the genomic sequence of Populus trichocarpa found 96 highly homologous regions distributed in 37 loci, suggesting the abundance and divergence of NBS‐encoding genes in the triploid poplar genome. Within subfamilies 1–3, the average non‐synonymous/synonymous substitution (ω) rates were < 1, indicating purifying selection on these RGAs, but some sites were clearly under diversifying selection with ω > 1. Many intergenic exchanges were also detected among these RGAs, indicating a probable role in homogenising NBS domains. Quantitative real‐time PCR analysis revealed dramatic variations in the transcript level of 18 RGAs in the mature leaves, bark and roots of the triploid poplar, and identified two RGAs that had significantly higher level of transcripts in bark, four RGAs in mature leaves, and 14 in the above‐ground portion of poplars, suggesting their probable roles in resistance against diseases attacking the organs. Our results shed light on genetic resources of poplar resistance and will be useful for further resistance gene isolation and exploitation.
Antioxidative enzymes and the Russian wheat aphid (Diuraphis noxia) resistance response in wheat (Triticum aestivum)
Authors: Moloi M. J. , Van Der Westhuizen A. J.
Published: March 2008

A crucial function of antioxidative enzymes is to remove excess reactive oxygen species (ROS), which can be toxic to plant cells. The effect of Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko), infestation on the activities of antioxidative enzymes was investigated in the resistant (cv. Tugela DN) and the near‐isogenic susceptible (cv. Tugela) wheat (Triticum aestivum L.). RWA infestation significantly induced the activity of superoxide dismutase, glutathione reductase and ascorbate peroxidase to higher levels in the resistant than in susceptible plants. These findings suggest the involvement of antioxidative enzymes in the RWA–wheat resistance response, which was accompanied by an early oxidative burst. The results are consistent with the role of ROS in the resistance response and the control of their levels to minimise toxic effects.
Obstacle stepping involves spinal anticipatory activity associated with quadrupedal limb coordination
Authors: Michel J. , Van Hedel H. J. A. , Dietz V.
Published: March 2008

Obstacle avoidance steps are associated with a facilitation of spinal reflexes in leg muscles. Here we have examined the involvement of both leg and arm muscles. Subjects walking with reduced vision on a treadmill were acoustically informed about an approaching obstacle and received feedback about task performance. Reflex responses evoked by tibial nerve stimulation were observed in all arm and leg muscles examined in this study. They were enhanced before the execution of obstacle avoidance compared with normal steps and showed an exponential adaptation in contralateral arm flexor muscles corresponding to the improvement of task performance. This enhancement was absent when the body was partially supported during the task. During the execution of obstacle steps, electromyographic activity in the arm muscles mimicked the preceding reflex behaviour with respect to enhancement and adaptation. Our results demonstrate an anticipatory quadrupedal limb coordination with an involvement of proximal arm muscles in the acquisition and performance of this precision locomotor task. This is presumably achieved by an up‐regulated activity of coupled cervico‐thoracal interneuronal circuits.
Neglect‐like visual exploration behaviour after theta burst transcranial magnetic stimulation of the right posterior parietal cortex
Authors: Nyffeler Thomas , Cazzoli Dario , Wurtz Pascal , Lüthi Mathias , Von Wartburg Roman , Chaves Silvia , Déruaz Anouk , Hess Christian W. , Müri René M.
Published: March 2008

The right posterior parietal cortex (PPC) is critically involved in visual exploration behaviour, and damage to this area may lead to neglect of the left hemispace. We investigated whether neglect‐like visual exploration behaviour could be induced in healthy subjects using theta burst repetitive transcranial magnetic stimulation (rTMS). To this end, one continuous train of theta burst rTMS was applied over the right PPC in 12 healthy subjects prior to a visual exploration task where colour photographs of real‐life scenes were presented on a computer screen. In a control experiment, stimulation was also applied over the vertex. Eye movements were measured, and the distribution of visual fixations in the left and right halves of the screen was analysed. In comparison to the performance of 28 control subjects without stimulation, theta burst rTMS over the right PPC, but not the vertex, significantly decreased cumulative fixation duration in the left screen‐half and significantly increased cumulative fixation duration in the right screen‐half for a time period of 30 min. These results suggest that theta burst rTMS is a reliable method of inducing transient neglect‐like visual exploration behaviour.
Feed‐forward excitation of striatal neuron activity by frontal cortical activation of nitric oxide signaling in vivo
Authors: Ondracek Janie M. , Dec Alexander , Hoque Kristina E. , Lim Sean Austin O. , Rasouli Golta , Indorkar Raksha P. , Linardakis John , Klika Brian , Mukherji Sawrav Josh , Burnazi Migena , Threlfell Sarah , Sammut Stephen , West Anthony R.
Published: March 2008

The gaseous neurotransmitter nitric oxide plays an important role in the modulation of corticostriatal synaptic transmission. This study examined the impact of frontal cortex stimulation on striatal nitric oxide efflux and neuron activity in urethane‐anesthetized rats using amperometric microsensor and single‐unit extracellular recordings, respectively. Systemic administration of the neuronal nitric oxide synthase inhibitor 7‐nitroindazole decreased spontaneous spike activity without affecting activity evoked by single‐pulse stimulation of the ipsilateral cortex. Train (30 Hz) stimulation of the contralateral frontal cortex transiently increased nitric oxide efflux in a robust and reproducible manner. Evoked nitric oxide efflux was attenuated by systemic administration of 7‐nitroindazole and the non‐selective nitric oxide synthase inhibitor NG‐nitro‐l‐arginine methyl ester. Train stimulation of the contralateral cortex, in a manner identical to that used to evoke nitric oxide efflux, had variable effects on spike activity assessed during the train stimulation trial, but induced a short‐term depression of cortically evoked activity in the first post‐train stimulation trial. Interestingly, 7‐nitroindazole potently decreased cortically evoked activity recorded during the train stimulation trial. Moreover, the short‐term depression of spike activity induced by train stimulation was enhanced following pretreatment with 7‐nitroindazole and attenuated after systemic administration of the dopamine D2 receptor antagonist eticlopride. These results demonstrate that robust activation of frontal cortical afferents in the intact animal activates a powerful nitric oxide‐mediated feed‐forward excitation which partially offsets concurrent D2 receptor‐mediated short‐term inhibitory influences on striatal neuron activity. Thus, nitric oxide signaling is likely to play an important role in the integration of corticostriatal sensorimotor information in striatal networks.
Do patients with psychogenic nonepileptic seizures produce trustworthy findings on neuropsychological tests?
Authors: Dodrill Carl B.
Published: March 2008

Summary

Drane et al. (2006) has recently raised the possibility that patients with psychogenic nonepileptic seizures (PNES) may make poor effort in taking neuropsychological tests in comparison with patients with epilepsy (ES). Therefore, findings previously reported with PNES patients may be in error, especially with regard to tests of mental abilities. Using the same measure of effort used by Drane et al. (2006) but with more broadly selected patients, this paper attempts to replicate their findings with new samples of ES (n = 65) and PNES (n = 32) cases. However, their findings could not be replicated, and no differences in test taking effort could be demonstrated across the groups. The highly selected samples of Drane et al. (2006) appear to be responsible for their results, and neuropsychological findings with PNES patients appear to be as trustworthy as those with ES patients.
Aborted and refractory status epilepticus in children: A comparative analysis
Authors: Lambrechtsen Florise A. C. P. , Buchhalter Jeffrey R.
Published: March 2008

Summary

Purpose: The aims of this retrospective study were: (1) to compare the demographics, clinical characteristics, etiology, and EEG findings of status epilepticus aborted with medication (ASE) and refractory status epilepticus (RSE), (2) to describe the treatment response of status epilepticus (SE), and (3) to determine predictors of long‐term outcome in children with SE.

Methods: Medical records and EEG lab logs with ICD‐9 diagnostic codes related to SE were reviewed. Patients younger than 18 years of age, hospitalized in 1994–2004 at the Mayo Clinic, Rochester, were included.

Results: One hundred fifty‐four children had SE; 94 (61%) had ASE, and 60 (39.0%) had RSE. Family history of seizures, higher seizure frequency score, higher number of maintenance antiepileptic drugs (AEDs), nonconvulsive SE, and focal or electrographic seizures on initial EEG were associated with RSE by univariate analysis. In‐hospital mortality was significantly higher in RSE (13.3%) than in ASE (2.1%). In the long term, survivors with RSE developed more new neurological deficits (p < 0.001) and more epilepsy (p < 0.004) than children with ASE. Children treated in a more aggressive fashion appeared to have better treatment responses (p < 0.001) and outcomes (p = 0.03). Predictors of poor outcome were long seizure duration (p < 0.001), acute symptomatic etiology (p = 0.04), nonconvulsive SE (NCSE) (p = 0.01), and age at admission <5 years (p = 0.05).

Discussion: Several patient and clinical characteristics are associated with development of RSE and poor outcome. Prospective, randomized trials that assess different treatment protocols in children with SE are needed to determine the optimal sequence and timing of medications.
Psychosocial outcomes in children two years after epilepsy surgery: Has anything changed?
Authors: Elliott Irene M. , Lach Lucyna , Kadis Darren S. , Smith Mary Lou
Published: March 2008

Summary

Purpose: We prospectively explored psychosocial outcomes in children (7–18 years) 2 years after epilepsy surgery. This study built on our previous one that examined these children 1 year after surgery.

Methods: Twenty children were studied using the Child Behavior Checklist (CBCL; a parent report instrument of potential behavioral and social problems) preoperatively, 1 year and 2 years after surgery. A comparison group of 12 children with medically refractory seizures was examined at comparable times. We conducted mixed factorial ANOVAs to determine group, time, and interaction effects, and regression analyses to assess factors driving significant (p ≤ 0.05) interactions. We also investigated the proportion of children scoring in the abnormal range over time.

Results: Significant main effects of time were observed on total behavior, externalizing, aggression, and delinquent behavior scales, with both groups reporting improvement. Main effects of group were observed for withdrawn and total competence scales, with the surgical group demonstrating favorable scores. Significant group × time interactions were observed on the social and social problems subscales. On both subscales, the surgical group demonstrated improvement over time, whereas the nonsurgical group experienced decline. Fifty percent of the surgical group remained seizure‐free. Seizure status and number of antiepileptic medications predicted changes in social scores. We did not observe a significant regression model for the social problems subscale.

Discussion: These findings suggest that change in social function may take time to develop after surgery. Prospective studies designed for longer periods are required to determine if improvements in other psychosocial domains are seen over time.
Solvent/detergent treatment of platelet concentrates enhances the release of growth factors
Authors: Burnouf Thierry , Tseng Yu H. , Kuo Ya P. , Su Chen Y.
Published: March 2008

BACKGROUND: Platelet (PLT) growth factors released by thrombin activation of autologous PLT concentrates (PCs) are used in clinics as PLT gels or releasates for tissue repair and wound healing applications. If allogeneic products are to be used for clinical or cell culture applications, a method of viral inactivation of the PC source of growth factors is desirable.

STUDY DESIGN AND METHODS: PLT‐derived growth factor‐AB (PDGF‐AB), transforming growth factor‐β1 (TGF‐β1), epidermal growth factor (EGF), and insulinlike growth factor‐1 (IGF‐1) in apheresis PC subjected to solvent/detergent (S/D) treatment with or without prior activation by CaCl2 and/or bovine thrombin were measured.

RESULTS: Mean (± standard deviation) PDGF‐AB, TGF‐β1, EGF, and IGF‐1 content was 13.8 ± 14.3, 16.6 ± 14.3, less than 0.0007, and 83.4 ± 33.4 ng per mL, respectively, in the starting PC. They increased to 184.4 ± 80.2, 192.2 ± 37.4, 2.2 ± 1.6, and 88.4 ± 33.5 after 1 percent tri‐n‐butyl phosphate (TnBP)‐1 percent Triton X‐45 treatment, respectively. Mean content was 84.6 ± 35.5, 63.8 ± 14.1, 0.9 ± 0.6, and 117.2 ± 34.9 ng per mL, respectively, in CaCl2‐activated PC and remained stable after subsequent S/D treatment (88.3 ± 45.9, 68.6 ± 27.2, 1.40 ± 1.0, and 112.4 ± 39.7 ng/mL, respectively). Two percent TnBP treatment yielded similar release as with TnBP‐Triton X‐45. Addition of bovine thrombin did not increase the release of growth factors.

CONCLUSION: S/D treatment efficiently releases PDGF‐AB, TGF‐β1, and EGF from nonactivated apheresis PCs and may be of interest to prepare virally inactivated allogeneic growth factors for clinical and cell culture applications.
Validation of Computed Tomography Image Integration into the EnSite NavX Mapping System to Perform Catheter Ablation of Atrial Fibrillation
Authors: RICHMOND LAURA , RAJAPPAN KIM , VOTH ERIC , RANGAVAJHALA VAMSEE , EARLEY MARK J. , THOMAS GLYN , HARRIS STUART , SPORTON SIMON C. , SCHILLING RICHARD J.
Published: March 2008

Introduction: The complex anatomy of the left atrium (LA) makes location of ablation catheters difficult using fluoroscopy alone, and therefore 3D mapping systems are now routinely used. We describe the integration of a CT image into the EnSite NavX System with Fusion and its validation in patients undergoing atrial fibrillation (AF) or left atrial tachycardia (AT) catheter ablation.

Methods and Results: Twenty‐three patients (61 ± 9.2 years, 16 male) with paroxysmal (14) and persistent (8) AF and persistent (1) AT underwent ablation using CT image integration into the EnSite NavX mapping system with the EnSite Fusion Dynamic Registration software module. In all cases, segmentation of the CT data was accomplished using the EnSite Verismo segmentation tool, although repeat segmentation attempts were required in seven cases. The CT was registered with the NavX‐created geometry using an average of 24 user‐defined fiducial pairs (range 9 to 48). The average distance from NavX‐measured lesion positions to the CT surface was 3.2 ± 0.9 mm (median 2.4 mm). A large, automated, retrospective test using registrations with random subsets of each patient's fiducial pairs showed this average distance decreasing as the number of fiducial pairs increased, although the improvement ceased to be significant beyond 15 pairs. In confirmation, those studies which had used 16 or more pairs had a smaller average lesion‐to‐surface distance (2.9 ± 0.7 mm) than those using 15 or fewer (4.3 ± 0.8 mm, P < 0.02). Finally, for the 13 patients who underwent left atrial circumferential ablation (LACA), there was no significant difference between the circumference computed using NavX‐measured positions and CT surface positions for either the left pulmonary veins (178 ± 64 vs. 177 ± 60 mm; P = 0.81) or the right pulmonary veins (218 ± 86 vs. 207 ± 81 mm; P = 0.08).

Conclusion: CT image integration into the EnSite NavX Fusion system was successful in all patients undergoing catheter ablation. A learning curve exists for the Verismo segmentation tool; but once the 3D model was created, the registration process was easily accomplished, with a registration error that is comparable with registration errors using other mapping systems with CT image integration. All patients went on to have subsequent successful ablation procedures. Where LACA was performed (13 patients), only four patients required segmental ostial lesions to achieve electrical isolation.
Changes in Left Atrial Anatomy Due to Respiration: Impact on Three‐Dimensional Image Integration During Atrial Fibrillation Ablation
Authors: ECTOR JORIS , DE BUCK STIJN , LOECKX DIRK , COUDYZER WALTER , MAES FREDERIK , DYMARKOWSKI STEVEN , BOGAERT JAN , HEIDBÜCHEL HEIN
Published: March 2008

Introduction: Patient respiration influences the accuracy of image integration approaches used during atrial fibrillation (AF) ablation procedures. We assessed both absolute and relative changes in left atrial (LA) and pulmonary venous (PV) anatomy due to respiration and their implications for 3D image integration.

Methods and Results: Intensity‐based segmentation of the LA and PVs was performed on cardiac computed tomography (CT) images obtained during both inspiration and expiration in 16 patients referred for AF ablation. A 3D LA‐PV surface model was reconstructed for each respiratory phase. Absolute and relative respiratory motion components were evaluated from corresponding landmarks in both models. The mean 3D respiratory motion distance for all four PVs was 19 ± 9 mm. The most important motion component was in the inferior direction, with a mean inferior motion distance of 15 ± 8 mm. The mean 3D respiratory motion of the PV centers due to relative geometrical changes was small at the ostial level (2.6 ± 1.4 mm, 95% CI 2.3‐3.0 mm) but significantly larger at the level of the first PV bifurcation (4.0 ± 2.3 mm, 95% CI 3.4‐4.6 mm, P < 0.001). Relative geometrical changes of the LA body were most pronounced in regions near the mitral valve, resulting in a changed configuration of the mitral annulus during inspiration.

Conclusions: Respiration causes important movements of the PVs and LA. Relative changes in LA–PV geometry are most pronounced in the distal PVs and in the LA body near the mitral valve. Therefore, these regions should be avoided during registration of pre‐ and per‐procedural images unless they are acquired in the same phase of respiration.
Evaluation of a Novel Ventricular Support Device with Defibrillation Capabilities in Canine and Porcine Animal Models
Authors: KILLINGSWORTH CHERYL R. , RIPPY MARIAN K. , VIRMANI RENU , ROLLINS DENNIS L. , McGIFFIN DAVID C. , IDEKER RAYMOND E.
Published: March 2008

Introduction: Sudden death is prevalent in heart failure patients. We tested an implantable ventricular support device consisting of a wireform harness with one or two pairs of integrated defibrillation electrode coils.

Methods and Results: The device was implanted into six pigs (36–44 kg) through a subxiphoid incision. Peak voltage (V) defibrillation thresholds (DFT) were determined for five test configurations compared with a control transvenous lead (RV to CanPect). Defibrillator can location (abdominal or pectoral) and common coil separation on the implant (0° or 60°) were studied.. The DFT for RV60 to LV60 + CanPect was significantly less than control (348 ± 57 vs 473 ± 27 V, P < 0.05). The DFTs for other vectors were similar to control except for RV0 to LV0 + CanAbd (608 ± 159 V). The device was implanted into 12 adult dogs for 42, 90, or 180 days with DFT and pathological examination performed at the terminal study. Cardiac pressures were determined at baseline, after implantation, and at the terminal study. The DFT was also determined in a separate group of four dogs at 42 days following implantation of the support device with one pair of defibrillation electrodes. The DFTs at implant and explant in dogs with one pair (8 ± 1.5 Joules [J] and 6 ± 1.9 J) or two pairs (8 ± 3.4 J and 7 ± 1.9 J) of defibrillation electrodes were not significantly different from each other but significantly less than control measured at the terminal study (18 ± 3.4 J). Left‐sided pressures were significantly decreased at explant but within expected normal ranges. Right‐sided pressures were not different except for RV systolic. Histopathology indicated mild to moderate epicardial inflammation and fibrosis, consistent with a foreign body healing response.

Conclusions: This defibrillation‐enabled ventricular support system maintained mechanical functionality for up to 6 months while inducing typical chronic healing responses. The DFT was equal to or lower than a standard transvenous vector.
Pathophysiology and Disease Progression of Atrial Fibrillation: Importance of Achieving and Maintaining Sinus Rhythm
Authors: COHEN MARC , NACCARELLI GERALD V.
Published: March 2008

Atrial fibrillation (AF) is a progressive disease in which arrhythmia‐induced remodeling facilitates evolution from paroxysmal AF to persistent and permanent AF. Changes in electrical, structural, and contractile properties of cardiac tissue that are thought to underlie AF maintenance and progression are reviewed. Also examined is the negative impact of AF on clinical outcomes, as well as the potential benefits of restoration and maintenance of sinus rhythm. Because of the limited efficacy and adverse effects of current antiarrhythmics, new antiarrhythmic drugs need to be developed that provide safer and more effective rhythm control in AF.
Age‐ and Genotype‐Specific Triggers for Life‐Threatening Arrhythmia in the Genotyped Long QT Syndrome
Authors: SAKAGUCHI TOMOKO , SHIMIZU WATARU , ITOH HIDEKI , NODA TAKASHI , MIYAMOTO YOSHIHIRO , NAGAOKA IORI , OKA YUKO , ASHIHARA TAKASHI , ITO MAKOTO , TSUJI KEIKO , OHNO SEIKO , MAKIYAMA TAKERU , KAMAKURA SHIRO , HORIE MINORU
Published: March 2008

Introduction: Patients with long QT syndrome (LQTS) become symptomatic in adolescence, but some become at age of ≥20 years. Since it remains unknown whether clinical features of symptomatic LQTS patients differ depending on the age of onset, we aimed to examine whether triggers for cardiac events are different depending on the age in genotyped and symptomatic LQTS patients.

Methods and Results: We identified 145 symptomatic LQTS patients, divided them into three groups according to the age of first onset of symptoms (young <20, intermediate 20–39, and older ≥40 years), and analyzed triggers of cardiac events (ventricular tachycardia, syncope, or cardiac arrest). The triggers were divided into three categories: (1) adrenergically mediated triggers: exercise, emotional stress, loud noise, and arousal; (2) vagally mediated triggers: rest/sleep; and (3) secondary triggers: drugs, hypokalemia, and atrioventricular (AV) block. In the young group, 78% of the cardiac events were initiated by adrenergically mediated triggers and 22% were vagally mediated, but none by secondary triggers. In contrast, the adrenergically mediated triggers were significantly lower in the intermediate group. The percentage of secondary triggers was significantly larger in the older group than in the other two groups (0% in young vs 23% in intermediate vs 72% in older; P < 0.0001). Concerning the subdivision of secondary triggers on the basis of genotype, hypokalemia was only observed in LQT1, drugs mainly in LQT2, and AV block only in LQT2.

Conclusion: Arrhythmic triggers in LQTS differ depending on the age of the patients, stressing the importance of age‐related therapy for genotyped LQTS patients.
Restoration of the Penis Following Amputation at Circumcision: Shaeer's A-Y Plasty
Authors: Shaeer Osama
Published: March 2008

Introduction

Male circumcision is one of the most commonly performed procedures worldwide. It has an estimated complication rate ranging from 0.1% to 35%. Amputation of the shaft is one of the most devastating complications reported, resulting from entrapment of the phallus between the blades of the clamp or from thermal injury due to the application of unipolar diathermy.

Aim

In this work, I describe the guidelines I adopted in the management of 32 male patients afflicted with amputation of the shaft of the penis upon circumcision.

Methods

“Shaeer's A-Y plasty” was performed for all patients, whereby the proximal corpora and crura were released from their attachment to the pubis and were advanced forward by insetting a specially configured fat flap into the resultant cavity. Skin grafts were used to cover the released penis.

Results

In all 32 cases, the released penis was within the normal range of penile length, and was cosmetically and functionally acceptable.

Conclusions

“Shaeer's A-Y plasty” is capable of restoring the native phallus following amputation, with preservation of both gender identity and physiological characteristics of the penis to a large extent.
Male Anorgasmia Treated with Oxytocin
Authors: IsHak Waguih William , Berman Daniel S. , Peters Anne
Published: March 2008

Introduction

This is a case report on male anorgasmia that was successfully treated with oxytocin. Oxytocin is increased during arousal and peaks during orgasm. More recently, a study on humans published in Nature has shown its value in social bonding, increasing trust, and enhancing the sense of well-being.

Aim

To test the effectiveness of administering oxytocin in a case of treatment-resistant anorgasmia.

Methods

The patient underwent a biopsychosocial evaluation by a psychiatrist trained in sexual medicine and sex therapy for male orgasmic disorder, acquired type. Medical conditions, effect of substances, and psychological issues were ruled out. The patient was properly consented to using oxytocin as an off-label trial. Oxytocin was administered using a nasal spray intracoitally because of its ultra-short half-life.

Results

Oxytocin was effective in restoring ejaculation.

Conclusions

A case of treatment-resistant male anorgasmia was successfully treated with intracoital administration of intranasal oxytocin.
Snoring as a Risk Factor for Sexual Dysfunction in Community Men
Authors: Hanak Viktor , Jacobson Debra J. , McGree Michaela E. , Sauver Jennifer St. , Lieber Michael M. , Olson Eric J. , Somers Virend K. , Gades Naomi M. , Jacobsen Steven J.
Published: March 2008

Introduction

Severe obstructive sleep apnea has been associated with sexual dysfunction; however, it is unclear whether milder forms of sleep disturbances might also be associated with sexual problems.

Aim

To evaluate the association between snoring and five measures of sexual dysfunction in a population-based sample of men.

Methods

A stratified random sample of men residing in Olmsted County, Minnesota completed a questionnaire containing questions from the Brief Male Sexual Function Inventory (BMSFI) and a sleep questionnaire.

Main Outcome Measures

Levels of sexual drive (libido), erectile function, ejaculatory function, sexual problem assessment, and sexual satisfaction as assessed by the BMSFI.

Results

Of 827 men with a regular sexual partner, subjects were divided into categories of heavy (N=95), moderate (N=573), and none/mild (N=159) snoring. Their median age was 64 years (range 51–90). The sexual satisfaction domain score was significantly lower in the heavy snoring group (P value=0.01). The odds of low sexual satisfaction was 2.3 (95% CI 1.2, 4.1) among the heavy snorers compared with the none/mild snoring group. This association remained statistically significant after adjustment for smoking, medical comorbidities, and mental health status. However, there was no significant difference in ejaculatory function, erectile function, sexual drive, and sexual problem assessment across snoring categories.

Conclusions

These data provide evidence of an association between snoring severity and reduced sexual satisfaction in a population of elderly community males. Snoring was not associated with biologic measures of sexual dysfunction.
Role of Chloride Channels in the Regulation of Corpus Cavernosum Tone: A Potential Therapeutic Target for Erectile Dysfunction
Authors: Chu Lau Lang , Adaikan P. Ganesan
Published: March 2008

Introduction

Recent electrophysiological recordings have identified the existence of outward, excitatory chloride (Cl−) currents in rat, rabbit, and human corpus cavernosum (CC) muscle cells.

Aim

The aim of this study was to investigate the physiological role of Cl− currents in the maintenance of cavernosal muscle tone in isolated rabbit CC tissues.

Methods

CC strips (1 × 1 × 5 mm) were suspended in tissue bath chambers for isometric tension experiments. Spontaneous cavernosal tone and contractions elicited by field stimulation or administration of established smooth muscle constrictors were examined in the presence of chloride channel (ClC) blockers, ni umic acid (NFA), and anthracene-9-carboxylic acid (A9C).

Main Outcome Measure

Both spontaneous myogenic activity and contractile responses to field stimulation, norepinephrine, histamine, and endothelin-1 were reduced by ClC blockers.

Results

In CC strips exhibiting intrinsic myogenic tone, NFA (30 and 100 µM) and A9C (1 mM) caused a relaxation of the tone. In addition, spontaneous contractile activity in CC was abolished in the presence of either ClC blocker. In CC strips precontracted with norepinephrine, histamine, and endothelin-1, both ClC blockers significantly reversed the tone. The ability of NFA and A9C to reverse norepinephrine-induced tone was unaffected by N  ω-nitro-L-arginine, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, and cis-N-[2-phenylcyclopentyl]-azacyclotridec-1-en-2-amine. In addition, neither indomethacin nor tetraethylammonium affected the relaxant response of NFA. NFA and A9C inhibited the neurogenic and norepinephrine-induced contractions in a concentration-dependent manner. While NFA exerted persistent inhibition on neurogenic contraction, inhibition of neurogenic contractions by A9C was readily reversible. On K+-depolarized CC, NFA induced a concentration-related relaxation, whereas A9C was inert, suggesting an additional mechanism of NFA on voltage-gated calcium channels.

Conclusions

These results underline the importance of Cl− currents as a mechanism in the maintenance of cavernosal tone produced by adrenergic and various endogenous constrictors. Thus, the modulation of Cl− current, as an attractive and effective approach to regulate penile erection, and specific ClC blockers, as potential erectogenic agents, merits further research.