bluuebunny/crossref_metadata_2025 huggingface dataset:
Aberrant activation of CDK5 is involved in the pathogenesis of OPIDN
Authors: Wang Ying‐Peng , Mou Dan‐lei , Song Jun‐Feng , Rao Zhi‐Ren , Li Duan , Ju Gong
Published: July 2006

Exposure to triorthocresyl phosphate (TOCP) may result in a late neurological complication, i.e. organophosphate‐induced delayed neuropathy (OPIDN). The aim of this study was to examine changes in levels of cyclin‐dependent kinase 5 (CDK5) and of its activator, p35/p25, in the spinal cord of hens treated by TOCP. After exposure to a single dose of TOCP, groups of adult hens were examined in 3, 5, 7, 9, 14, and 18 days after exposure. CDK5, p35/p25 expression and distribution in the lumbar spinal cord were evaluated by immunohistochemistry and Western blotting. The hens showed signs of OPIDN around day 9 after exposure. The number of p (phosphorylated) ‐CDK5 and p35 positive cells increased significantly. Co‐localization and mislocalization of p‐CDK5 and p35/p25 was identified and became evident in neurons around the 9th day. Meanwhile, CDK5, p‐CDK5, p35, p25 protein levels and p25/p35 ratio were increased, and peaked around the 9th day, then decreased. Some hens' unilateral common peroneal was treated by roscovitine 3 days after TOCP exposure. Axonal transport of these nerves was faster than of their opposite side and of those simply treated by TOCP. These findings indicate aberrant activation of CDK5 may be involved in the pathogenesis of OPIDN.
Styrylbenzoazole derivatives for imaging of prion plaques and treatment of transmissible spongiform encephalopathies
Authors: Ishikawa Kensuke , Kudo Yukitsuka , Nishida Noriyuki , Suemoto Takahiro , Sawada Tohru , Iwaki Toru , Doh‐ura Katsumi
Published: July 2006

Recent prevalence of acquired forms of transmissible spongiform encephalopathies (TSEs) has urged the development of early diagnostic measures as well as therapeutic interventions. To extend our previous findings on the value of amyloid imaging probes for these purposes, styrylbenzoazole derivatives with better permeability of blood–brain barrier (BBB) were developed and analyzed in this study. The new styrylbenzoazole compounds clearly labeled prion protein (PrP) plaques in brain specimens from human TSE in a manner irrespective of pathogen strain, and a representative compound BF‐168 detected abnormal PrP aggregates in the brain of TSE‐infected mice when the probe was injected intravenously. On the other hand, most of the compounds inhibited abnormal PrP formation in TSE‐infected cells with IC50 values in the nanomolar range, indicating that they represent one of the most potent classes of inhibitor ever reported. BF‐168 prolonged the lives of mice infected intracerebrally with TSE when the compound was given intravenously at the preclinical stage. The new compounds, however, failed to detect synaptic PrP deposition and to show pathogen‐independent therapeutic efficacy, similar to the amyloid imaging probes we previously reported. The compounds were BBB permeable and non‐toxic at doses for imaging and treatment; therefore, they are expected to be of practical use in human TSE.
Potential prey make excellent ornithologists: adaptive, flexible responses towards avian predation threat by Arabian Babblers Turdoides squamiceps living at a migratory hotspot
Authors: EDELAAR PIM , WRIGHT JONATHAN
Published: July 2006

During spring raptor migration, resident, group‐living, Arabian Babblers Turdoides squamiceps in Israel are exposed to many avian predators that differ in the level of predation threat that they pose. Accurate information about immediate safety while foraging may be provided by the sentinel, a high‐perched non‐foraging Babbler that actively scans and warns for predators. We tested whether, at this migratory hotspot, the bewildering number and diversity of potential avian predators (perhaps more than anywhere else in the world) may be more than a reliable sentinel could handle. We monitored ten Babbler groups regularly for a number of hours per day throughout the migration season, and scored whether the Babblers gave alarm calls when different bird species were in sight. Analyses showed that Babblers are very skilled in distinguishing between species of high and low predation threat (interspecific threat‐sensitivity). In addition, Babblers distinguished accurately between encounters with dangerous vs. harmless individuals from predator species of potentially high predation threat (intraspecific threat‐sensitivity). Overall, Babblers cautiously overestimated predation threat, probably because errors involving alarms for harmless predators have a lower fitness cost than errors involving attacks by dangerous predators that are ignored. However, fewer warnings were given for the more common predators of lower threat, which suggests that Babblers initially overestimated the risk of predation, but subsequently learned to assess the level of threat more accurately as soon as more information was available. Overall, our findings agree closely with theoretical predictions regarding adaptive and sophisticated anti‐predation behaviour in a variable world.
Feather mite abundance increases with uropygial gland size and plumage yellowness in Great Tits Parus major
Authors: GALVÁN ISMAEL , SANZ JUAN J.
Published: July 2006

Plumicolous feather mites are ectosymbiotic organisms that live on bird feathers. Despite their abundance and prevalence among birds, the ecology of the interaction between these organisms and their hosts is poorly known. As feather mites feed on oil that birds spread from their uropygial gland, it has been hypothesized, but never tested, that the number of feather mites increases with the size of the uropygial gland of their hosts. In this study the number of feather mites is considered with respect to uropygial gland size in a breeding population of Great Tits Parus major in order to test this hypothesis. As predicted, the number of feather mites correlated positively with the uropygial gland size of their hosts, showing for the first time that uropygial gland size can explain the variance in feather mite load among conspecifics. Previous studies relating feather mite load to plumage colour have suggested that feather mites may be parasitic or neutral. To confirm this, the yellowness of breast feathers was also assessed. However, the results ran in the opposite direction to that expected, showing a positive correlation between mite load and plumage yellowness, which suggests that further work is needed to give clear evidence for a specific nature of feather mites. However, Great Tits with higher mite loads had lower hatching and breeding success, which may support the idea that feather mites are parasites, although this effect must be taken with caution because it was only found in males. Age or sex effects were not found on the number of feather mites, and it is proposed that hormonal levels may not be sufficient to explain the variation in feather mite loads. Interestingly, a positive correlation was detected between uropygial gland size and plumage brightness, which could be a novel factor to take into account in studies of plumage colour.
The contribution of invertebrate taxa to moorland bird diets and the potential implications of land‐use management
Authors: BUCHANAN GRAEME M. , GRANT MURRAY C. , SANDERSON ROY A. , PEARCE‐HIGGINS JAMES W.
Published: July 2006

We reviewed the literature to determine the importance of invertebrates for moorland‐breeding birds and considered our findings with respect to the conservation of such species in the UK. The diets of many moorland birds consist predominantly of invertebrates, with a wide range of taxa recorded in the diets of moorland birds during the breeding season. Relatively few taxa (Arachnida, Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera and Oligochaeta) were widely taken, with Diptera and Coleoptera being the most important. Among these latter two insect orders, Carabidae, Curculionidae, Elateridae and Tipulidae were the most important families. Comparisons of the diets of bird families, treated separately according to whether data were derived from adults or chicks, showed that waders take more interstitial invertebrates than passerines, which themselves take more foliage invertebrates. Although we lack detailed experimental data with which to demonstrate the direct effect of particular moorland management prescriptions on some of these key invertebrate taxa for breeding birds, available data suggest that management regimes that create a mosaic of habitats are likely to be most beneficial. In particular, heterogeneity in vegetation structure and species composition, and the presence of wet flushes associated with the synchronized spring emergence of adults of certain insect species, are likely to increase invertebrate food resources for birds.
Insulin resistance, oxidative stress, hypertension, and leukocyte telomere length in men from the Framingham Heart Study
Authors: Demissie S. , Levy D. , Benjamin E. J. , Cupples L. A. , Gardner J. P. , Herbert A. , Kimura M. , Larson M. G. , Meigs J. B. , Keaney J. F. , Aviv A.
Published: July 2006

Insulin resistance and oxidative stress are associated with accelerated telomere attrition in leukocytes. Both are also implicated in the biology of aging and in aging‐related disorders, including hypertension. We explored the relations of leukocyte telomere length, expressed by terminal restriction fragment (TRF) length, with insulin resistance, oxidative stress and hypertension. We measured leukocyte TRF length in 327 Caucasian men with a mean age of 62.2 years (range 40–89 years) from the Offspring cohort of the Framingham Heart Study. TRF length was inversely correlated with age (r = –0.41, P < 0.0001) and age‐adjusted TRF length was inversely correlated with the Homeostatic Model Assessment of Insulin Resistance (HOMA‐IR) (r =–0.16, P = 0.007) and urinary 8‐epi‐PGF2α (r = –0.16, P = 0.005) – an index of systemic oxidative stress. Compared with their normotensive peers, hypertensive subjects exhibited shorter age‐adjusted TRF length (hypertensives = 5.93 ± 0.042 kb, normotensives = 6.07 ± 0.040 kb, P = 0.025). Collectively, these observations suggest that hypertension, increased insulin resistance and oxidative stress are associated with shorter leukocyte telomere length and that shorter leukocyte telomere length in hypertensives is largely due to insulin resistance.
Extraordinary plasticity in aging in Strongyloides ratti implies a gene‐regulatory mechanism of lifespan evolution
Authors: Gardner Michael P. , Gems David , Viney Mark E.
Published: July 2006

Aging evolves as the result of weakened selection against late‐acting deleterious alleles due, for example, to extrinsic mortality. Comparative studies of aging support this evolutionary theory, but details of the genetic mechanisms by which lifespan evolves remain unclear. We have studied aging in an unusual nematode, Strongyloides ratti, to gain insight into the nature of these mechanisms, in this first detailed examination of aging in a parasitic nematode. S. ratti has distinct parasitic and free‐living adults, living in the rat small intestine and the soil, respectively. We have observed reproductive and demographic aging in parasitic adults, with a maximum lifespan of 403 days. By contrast the maximum lifespan of free‐living adults is only 5 days. Thus, the two adults of S. ratti have evolved strikingly different rates of aging. Parasitic nematode species are frequently longer‐lived than free‐living species, presumably reflecting different extrinsic mortality rates in their respective niches. Parasitic and free‐living female S. ratti are morphologically different, yet genetically identical. Thus, the 80‐fold difference in their lifespans, the greatest plasticity in aging yet reported, must largely reflect evolved differences in gene expression. This suggests that interspecific differences in lifespan may evolve via similar mechanisms.
A Method of Combined SHPB Technique and BP Neural Network to Study Impact Response of Materials
Authors: Wang L. , Xu M. , Zhu J. , Shi S.
Published: July 2006

Abstract:  A new method combining the split Hopkinson pressure bar (SHPB) technique with the back‐propagation (BP) neural network program is proposed. By this method, the treated strain wave signals become smooth with less noises induced by the transverse inertia. Moreover, the dynamic rate‐dependent constitutive behaviour of materials can be identified, without any pre‐assumption of a constitutive model. It is found that by taking the experimentally measured data of strain, strain rate and time as ‘input’ and the corresponding data of stress as ‘output’ of the BP neural network, the dynamic constitutive behaviour with internal damage or phase transformation evolution is easy to be identified, where the time could represent either the internal damage evolution or phase transformation process accompanied with the deformation process. It is emphasised that the data learnt by the BP neural network must include both loading and unloading processes, if the whole loading and unloading response is to be correctly predicted. The comparisons between the predictions and experimental results are in good agreement for both polyamide (PA) polymer (as an example of nonlinear viscoelastic materials) and Ti–Ni alloy (as an example of superelastic materials with stress‐induced phase transformation).
A Comparative Study of Several Material Models for Prediction of Hyperelastic Properties: Application to Silicone‐Rubber and Soft Tissues
Authors: Martins P. A. L. S. , Natal Jorge R. M. , Ferreira A. J. M.
Published: July 2006

Abstract:  The correct modelling of constitutive laws is of critical importance for the analysis of mechanical behaviour of solids and structures. For example, the understanding of soft tissue mechanics, because of the nonlinear behaviour commonly displayed by the mechanical properties of such materials, makes common place the use of hyperelastic constitutive models. Hyperelastic models however, depend on sets of variables that must be obtained experimentally. In this study the authors use a computational/experimental scheme, for the study of the nonlinear mechanical behaviour of biological soft tissues under uniaxial tension. The material constants for seven different hyperelastic material models are obtained via inverse methods. The use of Martins's model to fit experimental data is presented in this paper for the first time. The search for an optimal value for each set of material parameters is performed by a Levenberg–Marquardt algorithm. As a control measure, the process is fully applied to silicone‐rubber samples subjected to uniaxial tension tests. The fitting accuracy of the experimental stress–strain relation to the theoretical one, for both soft tissues and silicone‐rubber (typically nonlinear) is evaluated. This study intents also to select which material models (or model types), the authors will employ in future works, for the analysis of human soft biological tissues.
A Probabilistic Evaluation of the Least Squares Strain Tensor Derived from a Three‐Dimensional Modular Strain Rosette Using the Monte‐Carlo Technique
Authors: Little E. G. , Tocher D. , Colgan D. , O'Donnell P.
Published: July 2006

Abstract:  Strain gradients give rise to a number of problems in the field of embedded three‐dimensional strain measurement. In order to avoid these problems a modular type three‐dimensional strain rosette was embedded into known strain fields and the data from the individual gauges compared with theoretical predictions. Finally, the least squares strain tensor was predicted from experimental data analysed using the Monte‐Carlo technique and the theoretical results forecast from finite element data taking into account the mechanical properties of the carrier, plug and prismatic bar. Some of the experimental results were found to correlate well with the theoretical values but some values in the least squares strain tensor, in particular under compression and torsional loading, departed considerably from the theoretical values. It was found that the effect of the measurement errors in the individual gauges combined with the matrix operations in the least squares strain tensor were responsible for biasing the resultant tensor data. However, the modular technique provided a solution to the problem of strain gradients.
Applicability of Optical Geometric Differentiation for Time‐average Geometric Moiré
Authors: Ragulskis M. , Saunoriene L.
Published: July 2006

Abstract:  Optical experimental method for analysis of derivatives of dynamic displacements from patterns of time‐average moiré fringes is proposed in this paper. Derived analytical relationships for one‐dimensional optical model are validated for two‐dimensional elastic structures performing in‐plane vibrations. The fact that digital image filtering techniques are normally required for the identification of time‐averaged super‐fringes does not lessen the practical value of the proposed method.
Reducing Unnecessary Right Ventricular Pacing with the Managed Ventricular Pacing Mode in Patients with Sinus Node Disease and AV Block
Authors: GILLIS ANNE M. , PÜRERFELLNER HELMUT , ISRAEL CARSTEN W. , SUNTHORN HENRI , KACET SALEM , ANELLI‐MONTI MICHAEL , TANG FENG , YOUNG MARTIN , BORIANI GIUSEPPE ,   On behalf of the Medtronic Enrhythm Clinical Study Investigators
Published: July 2006

Background: Frequent and unnecessary right ventricular apical pacing increases the risk of atrial fibrillation or congestive heart failure. We evaluated a new pacing algorithm, managed ventricular pacing (MVP) which automatically changes modes between AAI/R and DDD/R in patients receiving pacemakers for symptomatic bradycardia.

Methods: Patients were randomized to the MVP mode or DDD/R mode for 1 month and then crossed over to the alternate pacing modality for an additional month. On completion of the crossover phase, the pacing mode selected was individualized and patients were followed for an additional 4 months.

Results: Of the 129 patients who successfully completed the crossover study, the cumulative percent ventricular pacing was significantly reduced in the MVP mode (median 1.4%) compared to the DDD/R mode (median 89.6%, 94.0% relative reduction; 95% CI 89.3–98.8%, P < 0.001). Patients with sinus node disease (SND, n = 51) when compared to patients with AV block (AVB) (n = 68) experienced a greater reduction in ventricular pacing with the MVP mode compared to the DDD/R mode (median relative reduction 99.1%; 95% CI 97.5–99.9% vs median relative reduction 60.1%; 95% CI 16.7–93.9% P < 0.001). The reduced percent ventricular pacing during MVP was sustained over longer term follow‐up.

Conclusions: The majority of patients with a bradycardia indication for cardiac pacing do not require ventricular pacing most of the time. The MVP mode significantly reduces unnecessary right ventricular pacing. This mode benefits even patients with intermittent AVB and is sustained over longer term follow‐up.
The Risk Profile for Obstructive Sleep Apnea Does Not Affect the Recurrence of Atrial Fibrillation
Authors: PADELETTI LUIGI , GENSINI GIAN FRANCO , PIERAGNOLI PAOLO , RAVAZZI PIERANTONIO , DIOTALLEVI PAOLO , BALDI NICOLA , RUSSO VITANTONIO , ORAZI SERAFINO , OCCHETTA ERALDO , PADELETTI MARGHERITA , CORBUCCI GIORGIO , JELIC SANJA , BAROLD S. SERGE
Published: July 2006

Background: Obstructive sleep apnea (OSA) has been linked to increased prevalence and recurrence of atrial fibrillation (AF). We hypothesized that OSA may aggravate AF in patients with pacemakers implanted for sinus bradycardia who had documented paroxysmal AF.

Methods: Seventy‐two patients (36 M, aged 77 ± 6 years) completed the study. All patients received a dual‐chamber pacemaker equipped with diagnostic and preventive functions for AF. OSA was diagnosed with the Berlin Questionnaire, which is validated to identify patients with OSA. Four‐month continuous pacemaker recordings were collected for all patients.

Results: OSA was diagnosed in 28% of patients. Patients at high risk for OSA (HR group) and patients at low risk for OSA (LR group) were equivalent for gender, age, and body mass index. The rate of hypertension was higher in HR than in LR group (90% vs 44%, P < 0.01). The prevalence of paroxysmal AF during the study period was similar in HR and LR group (53% vs 44%, P = NS). Overall number of AF episodes per month was not significantly different between HR and LR group (7 ± 13 vs 36 ± 122, P = NS). Similarly, AF burden (AF%) was not significantly different between HR and LR group (0.3 ± 0.6 vs 2.0 ± 4.8, P = NS). Circadian distribution of AF episodes was similar in both groups.

Conclusion: Long‐term pacemaker recording of AF recurrence, AF burden, and its circadian distribution is similar in patients with paroxysmal AF at high risk for OSA and those at low risk for OSA.
Dynamic Changes of P‐Wave Duration and P‐Wave Axis During Head‐Up Tilt Test in Patients with Vasovagal Syncope
Authors: MITRO PETER , ŠPEGÁR JÁN
Published: July 2006

Background: The exact role of venous pooling in the pathogenesis of vasovagal syncope (VVS) is not fully elucidated. P‐wave duration on an electrocardiogram can serve as a measure of atrial volume.

Methods: Sixty‐six patients (15 men, 51 women, mean age 32 years) with unexplained syncope were enrolled in the study.
P‐wave duration and the P‐wave axis (PWA) were measured during passive head‐up tilt test (HUT) in order to evaluate dynamic changes of atrial filling in patients with VVS.

Results: HUT was positive in 40 patients (6 men, 34 women, mean age 32 ± 9 years) and negative in 26 patients (9 men, 17 women, mean age 33 ± 8 years). The P‐wave duration was significantly reduced in HUT‐positive patients at the onset of symptoms as compared to 5 minutes (88.8 ± 11.9 vs 96.2 ± 12.0 ms, P = 0.008), and baseline (88.8 ± 11.9 vs 96.8 ± 13.8 ms, P = 0.005). The P‐wave duration was significantly shorter at the onset of presyncope in HUT‐positive patients as compared to HUT‐negative patients (88.8 ± 11.9 vs 100.3 ± 11.2 ms, P = 0.0002). In HUT‐positive patients, a significant increase in PWA was found at the onset of symptoms when compared to baseline (67.7 ± 22.1° vs 47.9 ± 14.9°, P < 0.0001) and 5 minutes of HUT (67.7 ± 22.1° vs 54.4 ± 14.9°, P = 0.005). At the time of syncope, PWA was more inferior in HUT‐positive patients than in HUT‐negative patients (67.7 ± 22.1° vs 51.8 ± 13.8°, P = 0.015).

Conclusions: VVS is associated with the reduction in P‐wave duration and the increase in PWA, which can be a result of exaggerated venous pooling and reduction in atrial volume.
Effects of Angiotensin Converting Enzyme Inhibitor and Angiotensin II Receptor Blocker on Ventricular Defibrillation Threshold
Authors: KAMOCHI HIDEYUKI , YAMANOUCHI YOSHIO , SAKU KEIJIRO
Published: July 2006

Background: Angiotensin converting enzyme (ACE) inhibitors and Angiotensin II (AII) receptor blockers have previously been shown to be beneficial in treating patients with not only hypertension but also with cardiovascular diseases. Therefore, such drugs may potentially be used in patients with an implantable cardioverter defibrillator (ICD) who show cardiac dysfunctions.

Objective: This study aimed to determine effects of short‐term administration of the ACE inhibitor (CV‐3317) and the AII receptor blocker (CV‐11974, an active form of candesartan) on internal defibrillation threshold (DFT) in anesthetized canine hearts.

Methods: DFTs were evaluated using a “hot can” defibrillation lead system in: (a) seven dogs following three intravenous administrations of 20 cc saline; (b) 11 dogs that received intravenous CV‐3317 doses of 1 mg/kg, 10 mg/kg, and 50 mg/kg; and in (c) 10 dogs that were intravenously given 0.1 mg/kg, 1 mg/kg, and 10 mg/kg CV‐11974. DFTs were determined using a “down‐up down‐up” protocol.

Results: Mean DFT delivered energies at baseline and following three consecutive intravenous saline injections were 16.4 ± 9.3 J, 15.3 ± 7.5 J, 15.9 ± 7.1 J, and 15.5 ± 5.6 J, respectively. Those at baseline and following 1 mg/kg, 10 mg/kg, and 50 mg/kg intravenous CV‐3317 were 12.9 ± 6.4 J, 12.2 ± 6.4 J, 11.0 ± 6.6 J, and 11.9 ± 6.6 J, respectively. Similarly, those at baseline and after 0.1 mg/kg, 1 mg/kg, and 10 mg/kg CV‐11974 were 13 ± 6.6 J, 12.5 ± 6 J, 12.9 ± 5.8 J, and 13.2 ± 6.6 J, respectively. There were no significant differences between DFT at baseline and the others in each treatment group.

Conclusions: Since an ACE inhibitor and an AII receptor blocker did not alter DFT, such drugs may be useful in ICD patients without a decrease in safety margins.
Focal Atrial Tachycardia II: Management
Authors: ROBERTS‐THOMSON KURT C. , KISTLER PETER M. , KALMAN JONATHAN M.
Published: July 2006

Over the last decade there have been significant changes in the treatment of focal atrial tachycardia (AT). This review concentrates on the different approaches to the treatment of focal AT. Initial therapies included antiarrhythmic medications and surgery. However, with the advent of radiofrequency ablation, and the poor efficacy of pharmacological therapy, there has been a shift toward a primary ablative approach. Several different mapping techniques have been proposed. The different techniques, including P‐wave morphology and advanced three‐dimensional mapping, are discussed in this review.
Pulmonary Arterial Embolization of Pacemaker Lead Electrode Tip
Authors: ECKART ROBERT E. , HRUCZKOWSKI TOMASZ W. , LANDZBERG MICHAEL J. , AMES ALYSON , EPSTEIN LAURENCE M.
Published: July 2006

Complications with extraction of abundant endovascular systems increase with time since implantation. As the number of implanted devices increases, successful management of complications needs to be disseminated. We present a 46‐year‐old woman with endovascular leads placed 15 years previously requiring extraction. Using laser‐assistance the leads were removed, although the passive lead tips were unable to be extracted, and were retained in the superior vena cava. One lead tip embolized to the distal pulmonary bed within 24 hours of her operative procedure. Computed tomography and pulmonary arteriography suggested a near immediate thrombogenic process. A multidisciplinary approach was utilized to identify management strategies that allowed for a satisfactory patient outcome.
A Grave Case of Bradycardia
Authors: LEE GEOFFREY , MCGAVIGAN ANDREW D. , HILLOCK RICHARD J. , ROBERTS‐THOMSON KURT C. , STEVENSON IRENE H. , MOND HARRY G.
Published: July 2006

Tachycardia is a prominent feature of thyrotoxicosis. We present an unusual case of Graves' thyrotoxicosis presenting as profound symptomatic bradycardia.
Idiopathic Polymorphic Ventricular Tachycardia with Normal QT Interval in a Structurally Normal Heart
Authors: MECHLEB BASSAM K. , HADDADIN TARIQ Z. , ISKANDAR SAID B. , ABBOUD LUCIEN N. , FAHRIG STEPHEN A.
Published: July 2006

Polymorphic ventricular tachycardia (PVT) is a life‐threatening arrhythmia that is typically related to long QT syndrome, organic heart disease, electrolyte abnormalities, cardiotoxic drugs, or adrenergic stimulation. A review of the literature reveals that PVT with normal QT interval and without underlying cause is quite rare. We report a case of idiopathic spontaneous PVT with structurally normal heart and without electrolyte abnormalities, drug reactions, or evidence of catecholamine induced arrhythmia. We also review the literature on the electrocardiographic characteristics and management of idiopathic PVT.
Epicardial Ablation of Ventricular Tachycardia Associated with Isolated Ventricular Noncompaction
Authors: LIM HONG EUY , PAK HUI‐NAM , SHIM WAN JOO , RO YOUNG MOO , KIM YOUNG‐HOON
Published: July 2006

A 52‐year‐old man presented with sudden onset of palpitations and dizziness. Echocardiogram confirmed the diagnosis of isolated noncompaction of ventricular myocardium with moderated systolic dysfunction, and the electrocardiogram (ECG) revealed ventricular tachycardia (VT), of which the focus seemed to match an area of prominent left ventricular noncompaction on the 12‐lead surface ECG. Through the activation mapping from the endo‐ and epicardium, simultaneously, a discrete potential preceding the QRS during VT was observed at the anterolateral epicardial wall. He subsequently underwent radiofrequency ablation, and VT was successfully eliminated.
The short vitamin D receptor is associated with increased risk for generalized aggressive periodontitis
Authors: Park Kyung Sook , Nam Jung Hyun , Choi Jeomil
Published: July 2006

Background: Generalized aggressive periodontitis (GAP) exhibits severe inflammation and alveolar bone loss. Vitamin D receptor (VDR) regulates both bone metabolism and inflammation‐related genes, and its polymorphisms and haplotypes may affect the functional activity of the VDR protein in GAP.

Objective: We analysed the genetic effect of VDR start codon, intron, and exon polymorphisms, and their haplotypes on the development of GAP.

Materials and Methods: The VDR start codon 27823C>T (rs2228570, FokI), intron 8 60890G>A (rs154410, BsmI), and exon 9 61968T>C (rs731236, TaqI) polymorphisms were determined by using the polymerase chain reaction–restriction fragment length polymorphism analysis among 93 GAP patients and 143 healthy controls.

Results: The VDR start codon 27823*C/*C genotype was associated with an increased risk for GAP [odds ratio (OR)=1.83, p=0.028], but the intron 8 60880G>A and exon 9 61968T>C polymorphisms were not associated with GAP. The VDR haplotype homozygote ht1(C–G–T) carrying 27823*C allele was associated with a 1.8‐fold increased risk of GAP (OR=1.84, p=0.030).

Conclusion: These results demonstrate that the short VDR (27823*C/*C) protein may influence GAP susceptibility.
Java project on periodontal diseases. The natural development of periodontitis: risk factors, risk predictors and risk determinants
Authors: Van der Velden U. , Abbas F. , Armand S. , Loos B. G. , Timmerman M. F. , Van der Weijden G. A. , Van Winkelhoff A. J. , Winkel E. G.
Published: July 2006

Objective: To identify risk factors, risk predictors and risk determinants for onset and progression of periodontitis.

Material and Methods: For this longitudinal, prospective study all subjects in the age range 15–25 years living in a village of approximately 2000 inhabitants at a tea estate on Western Java, Indonesia, were selected. Baseline examination was carried out in 1987 and follow‐up examinations in 1994 and 2002. In 2002, 128 subjects could be retrieved from the original group of 255. Baseline examination included evaluation of plaque, bleeding on probing, calculus, pocket depth, attachment loss and presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, spirochetes and motile microorganisms.

Results: The mean attachment loss increased from 0.33 mm in 1987 to 0.72 mm in 1994 and 1.97 mm in 2002. Analysis identified the amount of subgingival calculus and subgingival presence of A. actinomycetemcomitans as risk factors, and age as a risk determinant, for the onset of disease. Regarding disease progression, the number of sites with a probing depth 5 mm and the number of sites with recession were identified as risk predictors and male gender as a risk determinant.

Conclusion: Screening of these parameters early in life could be helpful in the prevention of onset and progression of periodontal diseases.
Spurious associations in oral epidemiological research: the case of dental flossing and obesity
Authors: Hujoel P. P. , Cunha‐Cruz J. , Kressin N. R.
Published: July 2006

Background: Individuals with increased oral health awareness may also have increased general health awareness, and vice versa. Such associations between oral and general health awareness has the potential to induce spurious associations in oral epidemiological research.

Objective: To assess the extent to which oral self‐care patterns and general health awareness are confounded, we investigated the association between flossing and obesity, two lifestyle factors that are unlikely to be causally related.

Methods: A cross‐sectional study of 1497 individuals presenting for an initial periodontal exam by the specialist. Self‐reported flossing behaviors and body mass index (BMI) categories were related using logistic regression models.

Results: After adjustment for confounding variables, lack of daily flossing was associated in a dose‐dependent way with morbid obesity (odds ratio (OR), 20.3; 95% confidence interval (CI), 2.7–154.0), obesity (OR, 2.1; 95% CI, 1.5–2.9), and being overweight (OR, 1.7; 95% CI, 1.3–2.2). When restricting to never smokers, a significant relationship between obesity and lack of flossing remained.

Conclusion: The strong associations between two causally unrelated oral and general lifestyle characteristics indicate that simplistic epidemiologic methodology is unlikely to provide insights into causal mechanisms of oral diseases or oral‐systemic relationships.
A cross‐over study on the effect of various therapeutic approaches to morning breath odour
Authors: Faveri Marcelo , Hayacibara Mitsue F. , Cancine Pupio Giselle , Cury Jaime A. , Ota Tsuzuki Claudia , Hayacibara Roberto M.
Published: July 2006

Objective: The aim of this study was to investigate the effect of tongue scraping and inter‐dental flossing on morning bad breath in periodontally healthy subjects.

Methods: A four‐step blind, cross‐over study was conducted in 19 volunteers, divided into four groups: Group I: tooth brushing; Group II: tooth brushing and inter‐dental flossing; Group III: tooth brushing and tongue scraping; and Group IV: tooth brushing, inter‐dental flossing and tongue scraping. The volunteers performed these oral hygiene procedures three times a day for 7 days. Seven‐day wash‐out intervals were observed. Morning mouth breath was assessed organoleptically and by volatile sulphur compound concentrations.

Results: The highest mean organoleptic and volatile sulphur compound measurement values were found in the treatment groups in which tongue scraping was not performed and there were statistical differences between the two groups (p<0.05). In the organoleptic evaluation (p>0.05), inter‐dental flossing did not show any statistical improvement in the effect of tongue hygiene on morning bad breath, but it significantly reduced the concentration of volatile sulphur compounds (p<0.05).

Conclusion: The findings suggest that tongue scraping appears to be the most important hygienic procedure to reduce morning bad breath in periodontally healthy subjects.
Influence of different treatment approaches on non‐submerged and submerged healing of ligature induced peri‐implantitis lesions: an experimental study in dogs
Authors: Schwarz Frank , Jepsen Søren , Herten Monika , Sager Martin , Rothamel Daniel , Becker Jürgen
Published: July 2006

Objective: The aim of the present study was to evaluate non‐submerged and submerged healing of ligature induced peri‐implantitis in dogs.

Material and Methods: Peri‐implantitis was induced by ligature placement in five beagle dogs (n=30 implants). The defects were randomly and equally allocated in a split‐mouth design to either closed treatment+non‐submerged healing (CNS), or open treatment+submerged healing (OS) using an Er:YAG laser (ERL), an ultrasonic device (VUS), or plastic curettes+local application of metronidazole gel (PCM), respectively. The animals were sacrificed after 3 months. Clinical, radiological and histological (e.g. new bone‐to‐implant contact (BIC)) parameters were assessed.

Results: All treatment procedures resulted in statistically significant improvements of all clinical parameters at both CNS and OS implants. Radiological improvements were merely observed at OS implants. Histomorphometrical analysis revealed that all CNS implants exhibited comparable low amounts of new BIC (1.0–1.2%), while mean BIC was statistically significant higher in the respective OS groups [ERL (44.8%), PCM (14.8%), VUS (8.7%)].

Conclusion: Within the limits of the present study, it was concluded that (i) OS improved the outcome of treatment in comparison with CNS and (ii) ERL seemed to be more suitable to promote re‐osseointegration than PCM and VUS.
A comparison of non‐contact, subcutaneous, and rectal temperatures in captive owl monkeys (Aotus sp.)
Authors: Shelton L. J. , White C. E. , Felt S. A.
Published: July 2006

Background  Three methods of body temperature measurement were compared in owl monkeys: non‐contact infrared thermometry, subcutaneous transponder, and rectal probe.

Methods  Forty owl monkeys (Aotus sp.) were used. Animals were implanted with subcutaneous microchip transponders. Infrared thermometry was used at three different sites. All measurements were taken and repeated randomly.

Results  Infrared and subcutaneous measurements did not agree well with rectal thermometry. Subcutaneous and rectal temperatures were highly repeatable, and subcutaneous temperatures were most agreeable to rectal temperatures.

Conclusions  Further investigation is needed into subcutaneous implant sites and use of different infrared thermometers in this species.
Hepatitis viruses in non‐human primates
Authors: Makuwa M. , Souquière S. , Telfer P. , Bourry O. , Rouquet P. , Kazanji M. , Roques P. , Simon F.
Published: July 2006

Background  Previous epidemiological studies of rural human populations in Gabon reveal a high prevalence of human hepatitis A, B, C and D viruses. In order to investigate the prevalence of the blood‐born hepatitis viruses in apes and monkeys living in the same area, we performed an epidemiological survey of HBV, HCV and HDV in wild‐born non‐human primates.

Methods  We tested 441 wild‐born non‐human primates from Gabon and Congo and 132 imported monkeys for the presence of serological markers of HBV, HCV and HDV infections.

Results  None of Cercopithecidae monkeys were reactive against HBV/HDV and HCV. In contrast, 29.2% of wild‐born great apes (154 chimpanzees and 14 gorillas) were positive for HBV serological markers. Nine chimpanzees were in the replicative phase of HBV infection. None of these HBV infected chimpanzees exhibited symptoms or significant changes in serum clinical chemistry related to HBV infection.

Conclusions  The negativity to HCV‐related viruses and the negativity of the Cercopithecidae species tested against HBV/HDV do not allow us to definitively rule out the presence of an animal counterpart of human hepatitis viruses in non‐human primates.
GnRH‐antagonist mediated down‐regulation of the estrous cycle in marmosets
Authors: Marc Luetjens C. , Wesselmann Ramona , Kuhlmann Michael
Published: July 2006

Background  Because of its small size and unproblematic captivity behavior the marmoset monkey is an attractive New World primate model for early developmental questions. However, superovulation protocols used in Old World monkeys and women are not successful in the female marmoset. A novel protocol is needed to utilize these New World monkeys as an efficient animal model for in vitro fertilization experiments or embryo stem cell research.

Methods  To create such a protocol we first examined the effects of long‐term estrous cycle control, secondly, in a dose‐finding study, we determined the length of a down‐regulation protocol with a gonadotropic releasing hormone (GnRH)‐antagonist. Twenty‐nine female marmosets were grouped according to the number of estrous cycles, which had been controlled for a period of 12 months in which 88 cycles were monitored. Application of PGF2α in the mid‐luteal phase led to immediate onset of the follicular phase. The blood progesterone concentration rapidly declined and increased again on day 9–11.

Results  The results show that the controlled ovarian cycle length and progesterone response are not altered by the number of PGF2α injections. The rapid decline was similar in all groups, indicating that all animals, independent of the number of controlled cycles, react equally to multiple PGF2α injections. To determine the proper dosage for a GnRH‐antagonist (Cetrorelix), 12 animals in three groups of four female marmosets were treated with two different dosages and a sham dosage. Cetrorelix was applied in the mid‐luteal phase, three times over 2 days. In both Cetrorelix‐treated animal groups the early progesterone levels matched those in the controls. In the low‐dose treatment group [0.01 mg/100 g body weight (BW)] the expected progesterone rise on day 10 was delayed between 9 and 15 days whereas in the high‐dose treatment group (0.1 mg/100 g BW) the progesterone rise was delayed between 21 and 41 days. In the low‐dose group the steepness of the slope from day 20 onwards was almost identical to that of the control group. This was reflected in the bioCG levels measured.

Conclusions  Based on the GnRH‐antagonist studies, complete ovarian down‐regulation in female marmosets can be achieved by applying a low‐dose regimen, and intrinsic gonadotropins would not interfere with an ovarian superstimulation protocol.
Tuberculosis (Mycobacterium tuberculosis) in a pregnant baboon (Papio cynocephalus)
Authors: Martino M. , Hubbard G.B. , Schlabritz‐Loutsevitch N.
Published: July 2006

Background  Old World monkeys are considered more susceptible to tuberculosis (TB) than New World monkeys. Several cases of TB in baboons are described in the literature. The data regarding baboon reaction to the tuberculin skin test (TST) are controversial. Some authors described anergy in this species, while the others documented a positive reaction.

Case Report  An 8‐year‐old clinically healthy pregnant female baboon (Papio cynocephalus anubis) developed positive TST after 3 years of negative tests in captivity while not pregnant. Thoracic radiographs demonstrated three nodular densities in the lung.

Results  Histological examination of tracheobronchial lymph nodes revealed multiple coalescing pyogranulomas filled with caseonecrotic debris and mineralized foci with numerous large foreign body‐type and Langhans‐type multinucleated giant cells. The bacterial culture contained a slow growing Mycobacterium tuberculosis complex.

Conclusions  We describe, to the best of our knowledge, the first case of a positive TST in a wild caught, pregnant baboon with latent infection after 3 years in captivity.
Detection of viral agents in fecal specimens of monkeys with diarrhea
Authors: Wang Yuhuan , Tu Xinming , Humphrey Charles , McClure Harold , Jiang Xi , Qin Chuan , Glass Roger I. , Jiang Baoming
Published: July 2006

Background  Diarrheal disease is a major cause of morbidity and mortality in humans and animals, including non human primates. While the diagnostics for gastrointestinal bacterial and parasitic pathogens and their etiological role in disease are well established, little is known about the epidemiology, prevalence and role of viral agents in diarrheal illness among monkeys.

Methods  We collected fecal specimens from monkeys with diarrhea that were housed in two primate colonies, the Institute of Laboratory Animal Sciences, Beijing, China and the Yerkes National Primate Research Center, Georgia, USA. We screened these fecal specimens for rotaviruses and enteric adenoviruses 40/41 by using commercial EIA kits (Rotaclone and Adenoclone), enteroviruses by RT‐PCR and Southern blot hybridization, and picobirnaviruses by polyacrylamide gel electrophoresis and silver staining. Some of the specimens were examined by EM for coronaviruses and noroviruses.

Results  Of the 92 specimens from China, we found 63 (68%) positive for viruses, including enteroviruses (52%), enteric adenoviruses (21%), rotaviruses (20%), and picobirnaviruses (2%). Coronaviruses were detected in some specimens. Mixed infection of two or more viral agents was seen in 23 (25%) specimens. In the US collection, we detected enteroviruses and enteric adenoviruses in 76% (45/59) and 14% (7/50) of the specimens, respectively. Electron microscopy showed norovirus‐like particles in some specimens from both colonies.

Conclusions  Our findings indicate endemic infections with enteric viruses in monkeys of both colonies. The availability of new simian rotaviruses, enteric adenoviruses, enteroviruses, and coronaviruses and the discovery of noroviruses and picobirnaviruses may allow us to develop better diagnostics for these agents and determine which of these agents are clearly associated with gastroenteritis in monkeys.
Alteration of the menstrual cycle in baboons placed on tethering devices and moved to individual housing – a stress model for a follicular phase defect
Authors: Caperton L. , Eddy C. , Leland M.M. , Carey K.D. , McCarrey J.R.
Published: July 2006

Background  During an attempt to identify endocrine characteristics in the baboon that would more precisely predict ovulatory status for assisted reproductive techniques, we observed severe alterations in the menstrual cycle length upon introducing an environmental stress. This environmental stress involved moving animals from their baseline gang cage environment to individual indoor caging and placing them on a tethering apparatus.

Methods  Five adult female baboons were followed for changes in sex skin indicative of menstrual cycle timing and move from outdoor gang gages to individual indoor cages during the early follicular phase of their cycle. A tether device including a surgically implanted cannula was then installed to facilitate daily blood draws without sedation. Radioimmuonoassays were performed to monitor serum estradiol levels and lapraroscopic surveillance was used to confirm time of ovulation.

Results  Complete data sets were collected from four of the female baboons. In each case, a prolongation of the menstrual cycle was noted either during the cycle during which the females were moved to indoor caging or during the cycle immediately following the move. This prolongation was isolated to the follicular phase of the affected cycle.

Conclusions  We conclude that otherwise normal handling procedures, including movement to new caging, and/or installation of a tether device, can impart a stress effect on reproductively cycling adult female baboons, such that folliculogenesis is delayed.
Objective measures of health and well‐being in laboratory rhesus monkeys (Macaca mulatta)
Authors: Smith Joshua J. , Hadzic Vezira , Li Xiaobing , Liu Ping , Day Tiffany , Utter Amy , Kim Byounghoon , Washington Ida M. , Basso Michele A.
Published: July 2006

Background  Non‐human primates are an invaluable part of biomedical research. Strict regulations insure animals have a maximum likelihood of well‐being and optimum health during the course of experimental procedures. Objective assessment of well‐being is a critical component of these assurances.

Methods  Here we describe an objective and quantitative system we used to identify two well‐being concerns in laboratory rhesus monkeys (Macaca mulatta). We provide a series of indicators for use by laboratory personnel to promote laboratory primate well‐being. The indicators measure (1) potentially life threatening clinical concerns, (2) developing clinical issues, (3) atypical behaviors, and (4) laboratory performance. We include specific criteria to facilitate veterinary intervention.

Results  The assessment, applied to two case studies reported here, enabled swift veterinary intervention returning the animals to a healthy state.

Conclusions  The measures described here provide a battery of observable and objective measures across multiple dimensions that can further ensure both excellent science and veterinary care.