bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased Expression of HMGB‐1 in the Skin Lesions of Erythema Toxicum
Authors: Marchini Giovanna , Hultenby Kjell , Nelson Annika , Yektaei‐Karin Elham , Ståbi Berit , Lonne‐Rahm Solbritt , Ulfgren Ann‐Kristin , Brismar Hjalmar
Published: October 2007

Abstract:  At birth, commensal microbes penetrate into the skin of the human newborn, eliciting an acute rash, erythema toxicumn neonatorum. Histologically, the rash is characterized by an upregulation of proinflammatory activity and a local recruitment of immunocytes, including macrophages. High mobility group box chromosomal protein 1, a nuclear and cytosolic protein, is also a pro‐inflammatory cytokine released by macrophages in response to microbial stimulation. Here, we reasoned that macrophages but also keratinocytes might upregulate this protein in response to the first colonization and that high mobility group box chromosomal protein 1 might play a role as a proinflammatory mediator in the development and progression of erythema toxicum. Punch biopsy specimens from 1‐day‐old healthy infants, seven with and four without erythema toxicum were analyzed with indirect immunohistochemistry and two different antihigh mobility group box chromosomal protein 1 antibodies, immunofluorescence, nuclear counterstaining, confocal and immunoelectron imaging. We found relocation of nuclear high mobility group box chromosomal protein 1 into the cytoplasm in keratinocytes and macrophages in erythema toxicum. Cytoplasmatic high mobility group box chromosomal protein 1 was also found in melanocytes and did neither co‐locate with lysosomal‐associated membrane proteins nor with melanosomes. We speculate that terrestrial adaptation triggers the induction of the endogenous “danger signal” high mobility group box chromosomal protein 1 in the skin of the newborn infant, perhaps in response to the first commensal colonization and that this signal may contribute to alert the immune system and promote a protective immune response.
Diaper Dermatitis‐Frequency and Contributory Factors in Hospital Attending Children
Authors: Adalat Shazia , Wall David , Goodyear Helen
Published: October 2007

Abstract:  The incidence and prevalence of diaper dermatitis varies widely between published studies. It is a condition which causes considerable parental anxiety. To better understand the frequency of diaper dermatitis, treatment practices, and the current importance of previously identified etiologic factors, a questionnaire survey of parents who had children wearing diapers (n = 532) attending a large United Kingdom district general hospital was undertaken. At the time of survey, only 16% of the study population had diaper dermatitis. Forty‐eight percent of the study population had never had an episode of diaper dermatitis. In a multivariate analysis, current diaper dermatitis was independently associated with four factors: presence of oral thrush, number of previous episodes, frequency of diaper changes, and diarrhea. Recurrent episodes of diaper dermatitis were associated with increasing age, lack of barrier cream use, current diaper rash, and frequency of diaper changes. In the majority of children with diaper dermatitis at the time of survey, treatment had been instituted in the community. Diaper dermatitis usually presents and is treated successfully outside the hospital setting and is not a common clinical problem in secondary care.
Melanocytic Nevi in 2783 Children and Adolescents in Turkey
Authors: Dogan Gursoy
Published: October 2007

Abstract:  This study investigated the numbers of melanocytic nevi in Turkish children and adolescents. The research was conducted on 2783 subjects (age range, 7–14 yrs) at three elementary schools in Malatya, Turkey (latitude 38°N). Numbers of melanocytic nevi per subject were counted using a standard international protocol. Comparisons were made with subjects categorized according to age, sex and skin type. The mean melanocytic nevus count was 1.07 ± 2.37. A significant positive correlation was found between nevus count and age (p < 0.001). The mean count for boys was significantly higher than that for girls (p < 0.001). Subjects with skin type II had a higher mean melanocytic nevus count than the other three groups. This is the first study related to numbers of melanocytic nevi in Turkey. The findings reveal that Turkish children and adolescents have few melanocytic nevi compared to those elsewhere in the world. In line with previous reports on other populations, analysis showed that older age, skin type II, and male sex are associated with higher melanocytic nevus counts. The results underline the importance of ethnic background in melanocytic nevus development.
Lichen Planus in African Children: A Study of 13 Patients
Authors: Nnoruka Edith N.
Published: October 2007

Abstract  Lichen planus is an uncommonly encountered dermatosis in children, reported worldwide, however in sub‐Saharan Africa there is paucity of data on Lichen planus among children. The aim of this study was to document the clinical types of Lichen planus observed in children in South East Nigeria from 1998 to 2001; and to highlight any differences and similarities with adult disease. In all, 13 patients (eight boys and five girls) aged between 3 and 15 years were diagnosed with Lichen planus. The limbs were the most common sites of involvement for nine (69.2%) children. Classic Lichen planus was the commonest clinical variant in eight (61.5%), while extensive hypertrophic plaques were observed in three (23.1%), linear lesions in two (15.4%) and eruptive generalized Lichen planus in two (15.4%). Koebner phenomenon was documented in five (38.5%); mucosal involvement, which is very uncommon in children affected by this disease, occurred in three (23.1%). Only one child had pterygium formation in all 20 nails (total nail dystrophy). No child had scalp or palmoplantar involvement. Despite the endemicity of hepatitis B surface antigen in our environment, this study also revealed that liver function tests were not significantly different between children with Lichen planus and hepatitis B surface antigen and those who were negative for this antigen; while anti‐hepatitis C virus seropositivity was not recorded in any of these children.
Inhaler‐Induced Pigmentary Changes in a 14‐Year‐Old Girl
Authors: Connolly Maureen , Kennedy Cameron T.C.
Published: October 2007

Abstract:  We present a 14‐year‐old girl with self‐induced areas of hypo‐ and hyperpigmenation on her forearm as a result of applying 10 blasts of an asthmatic aerosol inhaler directly to her skin. We emphasize the importance of being aware of potential danger associated with the common metered‐dose inhaler when it is misused.
Cutis Laxa Associated with Central Hypothyroidism owing to Isolated Thyrotropin Deficiency in a Newborn
Authors: Koklu Esad , Gunes Tamer , Ozturk Mehmet Adnan , Akcakus Mustafa , Buyukkayhan Derya , Kurtoglu Selim
Published: October 2007

Abstract:  Cutis laxa is an uncommon entity characterized by laxity of the skin, which hangs in loose folds, producing an appearance of premature aging. It can be subdivided into congenital and acquired forms. Genetic forms of cutis laxa include at least three forms of recessive disease, an X‐linked form also termed occipital horn syndrome and an autosomal dominant form. Isolated pituitary hormone deficiency can be induced by many causes including mechanical destruction of the hypothalamo‐pituitary axis, neoplasm, inflammation, and injury and genetic defects of pituitary hormone production and secretion. Isolated‐thyrotropin deficiency has been considered to be a rare disease. We report a newborn with autosomal recessive form of congenital cutis laxa, who had congenital hypothyroidism owing to isolated thyrotropin deficiency. To the best of our knowledge, this is the first instance of this association to be reported in the literature.
Acne Arising in an Epidermal Nevus
Authors: Hivnor Major Chad M. , Yan Albert C. , Honig Paul J.
Published: October 2007

Abstract:  Epidermal nevi are benign congenital lesions that follow Blaschko lines. Epidermal nevi can demonstrate a variety of histologic patterns and contain hamartomatous hyperplasia of any epidermal or adnexal structure. We present the first reported instance of acne arising strictly within a preexisting keratinocytic epidermal nevus during puberty, which is a demonstration of genetic mosaicism in pilosebaceous units.
Transient Symptomatic Zinc Deficiency in a Breast‐fed Preterm Infant
Authors: Kiechl‐Kohlendorfer Ursula , Fink Franz‐Martin , Steichen‐Gersdorf Elisabeth
Published: October 2007

Abstract:  Transient, symptomatic zinc deficiency in breast‐fed, low‐birthweight infants is a rare, but probably underrecognized disorder hallmarked by periorificial and acral dermatitis. Unlike in acrodermatitis enteropathica, symptoms disappear when nursing ends. We report a breast‐fed, preterm infant with demarcated, erythematous, and exudative patches with overlying crusts on the perioral, perianal, and acral areas. Laboratory investigations revealed lowered zinc levels in the infant’s serum, but normal levels in his mother’s milk. Oral zinc supplementation resulted in total clearing of skin lesions within 4 weeks. Our patient’s presentation illustrates the importance of zinc in rapidly growing preterm infants and aims to stimulate awareness for this disorder. Symptomatic zinc deficiency can be easily diagnosed by careful examination and effectively treated with oral zinc substitution.
Acral Erythema with Oral Methotrexate in a Child
Authors: Varela Carly R. , McNamara Joseph , Antaya Richard J.
Published: October 2007

Abstract:  Acral erythema is a rare cutaneous reaction that has been associated with various chemotherapy regimens. Most occurrences have been described in adult patients. Recently, methotrexate has been implicated in the development of acral erythema; however, pediatric reports are few. All of the reports in the pediatric and adult literature have described patients receiving moderate to high‐dose intravenous methotrexate. Here, we describe an instance of standard‐dose oral methotrexate‐associated acral erythema in a young girl with acute lymphoblastic leukemia, and review the recent literature as it relates to pediatric patients.
Zosteriform Connective Tissue Nevus in a Pediatric Patient
Authors: BRAZZELLI VALERIA , MUZIO FRANCESCA , BARBAGALLO TANIA , FORNARA LUISA , DONADINI FEDERICA , GUERCI BARBARA , MANCINI LUCA , CALCATERRA VALERIA , LARIZZA DANIELA , BORRONI GIOVANNI
Published: October 2007

Abstract:  We report an 8‐year‐old girl affected by hypochromic, asymptomatic, acquired lesions with a paving‐stone aspect on the right lumbosacral area and proximal right leg. The results of serum and urine biochemical screening were normal, as was the bone survey A biopsy was performed. The clinical and histologic aspects led to the diagnosis of connective tissue nevus with zosteriform distribution.
Accentuated Varicella Exanthems Due to Cast Application
Authors: KARA ATES , KURTUL TULIN , ILKE NARLI , YILDIRIM INCI , DEVRIM ILKER , CENGIZ A. BÜLENT , TEZER HASAN , SEÇMEER GÜLTEN
Published: October 2007

Abstract:  We report a case of 14‐year‐old male with local augmentation of varicella zoster exanthems on the forearm on which cast application was performed. After 1 week, the first varicella zoster exanthems began to appear on the left forearm under the cast and trunk, while lesions on the other forearm and extremities were very rare. We postulated that the local pressure and heat increased the number of exanthems.
Occlusive Eccrine Hidradenitis Presented as a Reticulated Eruption on the Buttocks
Authors: MARTÍN JOSÉ M. , JORDÁ ESPERANZA , MONTEAGUDO CARLOS , ALONSO VICENT , VILLALÓN GUILLERMO , MOLINA INMACULADA
Published: October 2007

Abstract:  A 13‐month‐old girl presented a reticulated eruption of 2 months duration located on her buttocks. Histologically, a mononuclear cell inflammatory infiltration was found within and around the eccrine sweat glands, with epithelial cell damage. The lesions were related to several traumatic mechanisms involving the buttocks, such as crawling and repeated trauma with a bathmat carpet.
Unilateral Transient Reactive Papulotranslucent Acrokeratoderma in a Child
Authors: ERKEK EMEL
Published: October 2007

Abstract:  Transient reactive papulotranslucent acrokeratoderma is a rare, acquired, reactive, and episodic disorder of the palmar skin. Herein I report on a 6‐year‐old child with unilateral involvement and associated with ipsilateral hyperhidrosis and pruritus. Further observations are required for unraveling the etiopathogenesis of this disorder and its accurate classification.
Genital Tuberculid in a Female Child: A New Entity (Childhood Vulval Tuberculid)
Authors: PANDHI DEPIKA , MEHTA SHILPA , SINGAL ARCHANA
Published: October 2007

Abstract:  Localized tuberculid has been infrequently reported in the literature. Most of these reports are of papulonecrotic tuberculids localized to the penis, an entity designated as “penis tuberculid.” In females, such a localized genital tuberculid has not been documented till date. We report an 11‐year‐old girl with lichen scrofulosorum confined to the vulva, associated with cervical and inguinal tubercular lymphandenitis.
An Unusual Presentation of Juvenile Xanthogranuloma
Authors: MOTEGI SEI‐ICHIRO , NAGAI YAYOI , AMANO HIROO , TAMURA ATSUSHI , ISHIKAWA OSAMU
Published: October 2007

Letters to the Editor are welcomed for publication (subject to editing). Letters must be signed by all authors, and must not exceed two pages of text including references. Letters should not duplicate material submitted or published in other journals. Prepublication proofs will not be provided.
Retigabine: Has the Orphan Found a Home?
Authors: Ben-Menachem Elinor
Published: October 2007

Randomized, Multicenter, Dose-Ranging Trial of Retigabine for Partial-Onset Seizures. Porter RJ, Partiot A, Sachdeo R, Nohria V, Alves WM; 205 Study Group. Neurology 2007;68(15):1197–1204. OBJECTIVE: To evaluate the efficacy and safety of retigabine 600, 900, and 1,200 mg/day administered three times daily as adjunctive therapy in patients with partial-onset seizures. METHODS: A multicenter, randomized, double-blind, placebo-controlled trial was performed. After an 8-week baseline phase, patients were randomized to a 16-week double-blind treatment period (8-week forced titration and 8-week maintenance) followed by either tapering or entry into an open-label extension study. Primary efficacy was the percentage change from baseline in monthly seizure frequency and compared across treatment arms. Secondary efficacy comparisons included the proportion of patients experiencing 50% reduction in seizure frequency (responder rate), emergence of new seizure types, and physician assessment of global clinical improvement. Safety/tolerability assessments included adverse events (AEs), physical and neurologic examinations, and clinical laboratory evaluations. Efficacy analyses were performed on the intent-to-treat population. RESULTS: Of the 399 randomized patients, 279 (69.9%) completed the double-blind treatment period. The median percent change in monthly total partial seizure frequency from baseline was −23% for 600 mg/day, −29% for 900 mg/day, and −35% for 1,200 mg/day vs −13% for placebo ( p < 0.001 for overall difference across all treatment arms). Responder rates for retigabine were 23% for 600 mg/day, 32% for 900 mg/day ( p = 0.021), and 33% for 1,200 mg/day ( p = 0.016), vs 16% for placebo. The most common treatment-emergent AEs were somnolence, dizziness, confusion, speech disorder, vertigo, tremor, amnesia, abnormal thinking, abnormal gait, paresthesia, and diplopia. CONCLUSION: Adjunctive therapy with retigabine is well tolerated and reduces the frequency of partial-onset seizures in a dose-dependent manner.
Animal Modeling of Poststroke Seizures and Epilepsy: 5-Year Update
Authors: Kelly Kevin M.
Published: October 2007

Poststroke seizures and epilepsy have been described in numerous clinical and epidemiological studies over many years. In contrast, the pathophysiological events occurring in injured brain that establish poststroke epileptogenesis and epilepsy are not known. However, in the last several years, animal modeling has made significant inroads toward an improved understanding of the progressive biochemical, anatomical, and physiological changes associated with both early and late seizures following stroke. A review of animal studies of poststroke seizures and epilepsy is presented.
Go “West,” Young Man…The Quest for Animal Models of Infantile Spasms (West Syndrome)
Authors: Baram Tallie Z.
Published: October 2007

Model of Infantile Spasms Induced by N-methyl-D-aspartic Acid in Prenatally Impaired Brain. Velisek L, Jehle K, Asche S, Veliskova J. Ann Neurol 2007;61(2):109–119. OBJECTIVE: Infantile spasms (a catastrophic epileptic syndrome of childhood) are insensitive to classic antiepileptic drugs. New therapies are limited by lack of animal models. Here we develop a new model of flexion spasms based on prenatal exposure to betamethasone combined with postnatal administration of N-methyl-D-aspartic acid (NMDA) and determine brain structures involved in the induction of flexion spasms. METHODS: Pregnant rats received two doses of betamethasone on day 15 of gestation. Offspring was injected with NMDA on postnatal day 15. Effects of adrenocorticotropin therapy on the development of age-specific flexion spasms were determined and electroencephalographic correlates recorded. C-fos immunohistochemistry and [14C]2-deoxyglucose imaging identified brain structures involved in the development of flexion spasms. RESULTS: Prenatal betamethasone exposure sensitizes rats to development of NMDA-induced spasms and, most importantly, renders the spasms sensitive to adrenocorticotropin therapy. Ictal electroencephalogram results correspond to human infantile spasms: electrodecrement or afterdischarges were observed. Imaging studies defined three principal regions involved in NMDA spasms: limbic areas (except the dorsal hippocampus), hypothalamus, and the brainstem. INTERPRETATION: Despite certain limitations, our new model correlates well with current infantile spasm hypotheses and opens an opportunity for development and testing of new effective drugs.
GABA Excites and Sculpts Immature Neurons Well before Delivery: Modulation by GABA of the Development of Ventricular Progenitor Cells
Authors: Ben-Ari Yehezkel
Published: October 2007

Excitatory GABA Action Is Essential for Morphological Maturation of Cortical Neurons in Vivo. Cancedda L, Fiumelli H, Chen K, Poo MM. J Neurosci 2007;27(19):5224–5235. GABA exerts excitatory actions on embryonic and neonatal cortical neurons, but the in vivo function of this GABA excitation is essentially unknown. Using in utero electroporation, we eliminated the excitatory action of GABA in a subpopulation of rat ventricular progenitors and cortical neurons derived from these progenitors by premature expression of the Cl– transporter KCC2, as confirmed by the changes in the reversal potential of GABA-induced currents and the resting membrane potential after GABAA receptor blockade. We found that radial migration to layer II/III of the somatosensory cortex of neurons derived from the transfected progenitors was not significantly affected, but their morphological maturation was markedly impaired. Furthermore, reducing neuronal excitability of cortical neurons in vivo by overexpressing an inward-rectifying K+ channel, which lowered the resting membrane potential, mimicked the effect of premature KCC2 expression. Thus, membrane depolarization caused by early GABA excitation is critical for morphological maturation of neonatal cortical neurons in vivo.
Effectiveness and Efficiency of Controlling Campylobacter on Broiler Chicken Meat
Authors: Havelaar Arie H. , Mangen Marie‐Josee J. , De Koeijer Aline A. , Bogaardt Marc‐Jeroen , Evers Eric G. , Jacobs‐Reitsma Wilma F. , Van Pelt Wilfrid , Wagenaar Jaap A. , De Wit G. Ardine , Van Der Zee Henk , Nauta Maarten J.
Published: October 2007

Campylobacter bacteria are an important cause of foodborne infections. We estimated the potential costs and benefits of a large number of possible interventions to decrease human exposure to Campylobacter by consumption of chicken meat, which accounts for 20–40% of all cases of human campylobacteriosis in the Netherlands. For this purpose, a farm‐to‐fork risk assessment model was combined with economic analysis and epidemiological data. Reduction of contamination at broiler farms could be efficient in theory. However, it is unclear which hygienic measures need to be taken and the costs can be very high. The experimental treatment of colonized broiler flocks with bacteriophages has proven to be effective and could also be cost efficient, if confirmed in practice. Since a major decrease of infections at the broiler farm is not expected in the short term, additional measures in the processing plant were also considered. At this moment, guaranteed Campylobacter‐free chicken meat at the retail level is not realistic. The most promising interventions in the processing plant are limiting fecal leakage during processing and separation of contaminated and noncontaminated flocks (scheduling), followed by decontamination of the contaminated flock. New (faster and more sensitive) test methods to detect Campylobacter colonization in broilers flocks are a prerequisite for successful scheduling scenarios. Other methods to decrease the contamination of meat of colonized flocks such as freezing and heat treatment are more expensive and/or less effective than chemical decontamination.
What Motivates Individuals to Protect Themselves from Risks: The Case of Wildland Fires
Authors: Martin Ingrid M. , Bender Holly , Raish Carol
Published: October 2007

This research investigates the cognitive perceptual process that homeowners go through when faced with the decision to protect themselves from the risk of wildfires. This decision can be examined by looking at the interaction between the integrated protection motivation theory—transtheoretical model and different levels of homeowners' subjective knowledge related to wildfire risks. We investigated the role of motivation, decision stages of risk readiness, and subjective knowledge on the number of risk‐mitigating actions undertaken by homeowners living in high‐risk communities. The results indicate that homeowners who are in an early or precontemplative stage (both low and high subjective knowledge) as well as low knowledge contemplatives are motivated by their perceived degree of vulnerability to mitigate the risk. In contrast, high knowledge contemplatives' potential behavioral changes are more likely to be motivated by increasing their perceptions of the severity of the risk. Risk‐mitigating behaviors undertaken by high knowledge action homeowners are influenced by their perceptions of risk severity, self‐efficacy, and response efficacy. In contrast, the low knowledge action homeowners engage in risk reduction behaviors without the influence of any of the PMT variables; demonstrating their motivation to emulate others in their community. These results have implications for the type of information that should be used to effectively communicate risks in an effort to influence the diverse homeowner segments to engage in risk‐reduction behaviors.
What Comes After the Prestige Disaster? An Entropic Approach to Modeling the Recurrence of Major Oil Tanker Spills in Galicia
Authors: Solana‐Ortega Alberto , Solana Vicente
Published: October 2007

A methodology is presented to investigate the recurrence of extraordinary events. The approach is fully general and complies with a canon of inference establishing a set of basic rationality requirements scientific reasoning should satisfy. In particular, we apply it to model the interarrival time between disastrous oil spills in the Galician coast in the northwest of Spain, one of the greatest risk areas in the world, as confirmed by the Prestige accident of November 2002. We formulate the problem within the logical probability framework, using plausible logic languages with observations to allow the appropriate expression of evidences. Therein, inference is regarded as the joint selection of a pair of reference and inferred probability distributions, which better encode the knowledge about potential times between incidents provided by the available evidences and other higher‐order information at hand. To solve it, we employ the REF relative entropy method with fractile constraints. Next, we analyze the variability of the joint entropic solution, as knowledge that a time has elapsed since the last recorded spill is added, by conditioning the evidences. Attention is paid to the variability of two representative parameters: the average reference recurrence time and an inferred characteristic probability fractile for the time to an event. In contrast with classical results, the salient consequence is their nonconstancy with the elapsed time and the appearance of a variability pattern indicating an observational memory, even under the assumption of one‐parameter exponential models, traditionally regarded as memoryless. Tanker accidentality is therefore dynamic, changing as time goes on with no further accidents. Generality of the methodology entails that identical conclusions would apply to hazard modeling of any other kind of extraordinary phenomena. This should be considered in risk assessment and management.
An Empirical Test of Competing Theories of Hazard‐Related Trust: The Case of GM Food
Authors: Allum Nick
Published: October 2007

Few scholars doubt the importance of trust in explaining variation in public perception of technological risk. Relatively little, however, is known about the particular types of judgments that people use in granting or withholding trust. This article presents findings from an empirical study that explores several dimensions of trust relevant for citizens' judgments of scientists involved in the development of GM food. The relationship between particular dimensions of trust and perceptions of GM food risk is also explored, using structural equation modeling. Results suggest that trust judgments based on the perception of shared values are most important in relation to GM food risk, but that judgments about scientists' technical competence are also important.
Assessments of Direct Human Exposure—The Approach of EU Risk Assessments Compared to Scenario‐Based Risk Assessment
Authors: Wormuth Matthias , Demou Evangelia , Scheringer Martin , Hungerbühler Konrad
Published: October 2007

The awareness of potential risks emerging from the use of chemicals in all parts of daily life has increased the need for risk assessments that are able to cover a high number of exposure situations and thereby ensure the safety of workers and consumers. In the European Union (EU), the practice of risk assessments for chemicals is laid down in a Technical Guidance Document; it is designed to consider environmental and human occupational and residential exposure. Almost 70 EU risk assessment reports (RARs) have been finalized for high‐production‐volume chemicals during the last decade. In the present study, we analyze the assessment of occupational and consumer exposure to trichloroethylene and phthalates presented in six EU RARs. Exposure scenarios in these six RARs were compared to scenarios used in applications of the scenario‐based risk assessment approach to the same set of chemicals. We find that scenarios used in the selected EU RARs to represent typical exposure situations in occupational or private use of chemicals and products do not necessarily represent worst‐case conditions. This can be due to the use of outdated information on technical equipment and conditions in workplaces or omission of pathways that can cause consumer exposure. Considering the need for exposure and risk assessments under the new chemicals legislation of the EU, we suggest that a transparent process of collecting data on exposure situations and of generating representative exposure scenarios is implemented to improve the accuracy of risk assessments. Also, the data sets used to assess human exposure should be harmonized, summarized in a transparent fashion, and made accessible for all risk assessors and the public.
The Risk Criteria for Assessment of Temporary Changes in a Nuclear Power Plant
Authors: Čepin Marko
Published: October 2007

Risk criterion is a term that may distinguish between what is considered as an acceptable level of safety and what is not. One of the ways of determining quantitative risk criteria for temporary changes in a nuclear power plant considering probabilistic safety assessment is presented. Risk criteria are based on timing and on time duration of the change. Several examples of temporary changes in a nuclear power plant were examined to evaluate the criteria. Results show that it is possible to determine a set of risk criteria for temporary changes. Risk criteria can represent a standpoint for risk‐informed decision making.
Managing the Risk of Uncertain Threshold Responses: Comparison of Robust, Optimum, and Precautionary Approaches
Authors: Lempert Robert J. , Collins Myles T.
Published: October 2007

Many commentators have suggested the need for new decision analysis approaches to better manage systems with deeply uncertain, poorly characterized risks. Most notably, policy challenges such as abrupt climate change involve potential nonlinear or threshold responses where both the triggering level and subsequent system response are poorly understood. This study uses a simple computer simulation model to compare several alternative frameworks for decision making under uncertainty—optimal expected utility, the precautionary principle, and three different approaches to robust decision making—for addressing the challenge of adding pollution to a lake without triggering unwanted and potentially irreversible eutrophication. The three robust decision approaches—trading some optimal performance for less sensitivity to assumptions, satisficing over a wide range of futures, and keeping options open—are found to identify similar strategies as the most robust choice. This study also suggests that these robust decision approaches offer a quantitative, decision analytic framework that captures the spirit of the precautionary principle while addressing some of its shortcomings. Finally, this study finds that robust strategies may be preferable to optimum strategies when the uncertainty is sufficiently deep and the set of alternative policy options is sufficiently rich.
Decision Making During Nuclear Power Plant Incidents—A New Approach to the Evaluation of Precursor Events
Authors: Smith C. L. , Borgonovo E.
Published: October 2007

Renewed interest in precursor analysis has shown that the evaluation of near misses is an interdisciplinary effort, fundamental within the life of an organization for reducing operational risks and enabling accident prevention. The practice of precursor analysis has been a part of nuclear power plant regulation in the United States for over 25 years. During this time, the models used in the analysis have evolved from simple risk equations to quite complex probabilistic risk assessments. But, one item that has remained constant over this time is that the focus of the analysis has been on modeling the scenario using the risk model (regardless of the model sophistication) and then using the results of the model to determine the severity of the precursor incident. We believe that evaluating precursors in this fashion could be a shortcoming since decision making during the incident is not formally investigated. Consequently, we present the idea for an evaluation procedure that enables one to integrate current practice with the evaluation of decisions made during the precursor event. The methodology borrows from technologies both in the risk analysis and the decision analysis realms. We demonstrate this new methodology via an evaluation of a U.S. precursor incident. Specifically, the course of the incident is represented by the integration of a probabilistic risk assessment model (i.e., the risk analysis tool) with an influence diagram and the corresponding decision tree (i.e., the decision analysis tools). The results and insights from the application of this new methodology are discussed.
Prolonged Transient Atrial Electrical Silence Following Termination of Chronic Atrial Tachyarrhythmias
Authors: TURITTO GIOIA , SAPONIERI CESARE , ONUORA AFAMEFUNA , EL‐SHERIF NABIL
Published: October 2007

Introduction:

Atrial standstill is a rare heterogeneous arrhythmia characterized by electrical and mechanical standstill and electrical inexcitability. A long‐lasting progressive form is seen with cardiac and neuromuscular diseases, and a familial or idiopathic form may have a genetic basis. A transient form was described secondary to drug intoxication, electrolyte imbalance, cardiac inflammation, and ischemia.

Methods:

We investigated three patients with long‐standing atrial tachyarrhythmia (AT) (atrial flutter in two, and focal atrial tachycardia in one). All patients underwent a complete electrophysiological study with mapping of right and left atrial activity and radiofrequency ablation (RF Abl) of AT.

Results:

Following RF Abl of AT, all three patients manifested transient atrial electrical silence in the absence of known reversible causes. Atrial electrical silence was observed when, following AT termination, an escape atrioventricular (AV) junctional rhythm (in two patients) and an escape VVI pacemaker rhythm (in one patient) showed transient ventriculo‐atrial (VA) conduction block (up to 30 seconds). A dominant sinus rhythm was observed to return 30 minutes, 90 minutes, and 12 hours, respectively, in the three patients. Two patients received a dual chamber pacemaker and a decision was made not to upgrade the patient with VVI pacemaker.

Discussion and Conclusions:

The present report expands the spectrum of the syndrome of atrial standstill and raises interesting questions regarding possible electrophysiologic mechanism(s) of prolonged post overdrive atrial standstill. The report suggests that chronic overdrive of sinus and subsidiary atrial pacemakers may result in calcium overloading of cardiac cells, which is known to cause suppression of pacemaker activity as well as increased intracellular resistance. These mechanisms can possibly result in either prolonged suppression of sinus and atrial pacemaker activity and/or pacemaker exit block.
Longitudinal Echocardiographic Follow‐Up in Children with Congenital Complete Atrioventricular Block
Authors: BEAUFORT‐KROL GERTIE C.M. , SCHASFOORT‐VAN LEEUWEN MIEK J.M. , STIENSTRA YMKJE , BINK‐BOELKENS MARGREET Th.E.
Published: October 2007

Background: Due to a low heart rate (HR) in children with congenital complete atrioventricular block (CCAVB), a larger stroke volume of the left ventricle (LV) may be expected. If so, end‐diastolic (LVEDD) and end‐systolic (LVESD) diameters may be enlarged and even dilated cardiomyopathy (DCM) may occur. The aim of this study was to answer the question if children with CCAVB develop LV dilatation. Furthermore, we investigated whether LV dilatation would decrease after pacing.

Methods: We longitudinally evaluated echocardiographic data (LVEDD, LVESD, shortening fraction [SF]) in 36 children with CCAVB. Age at the first visit was 2.5 ± 3.3 years (mean ± SD); follow‐up 10.6 ± 7.3 years.

Results: Three children had DCM, already at 1st visit. LVEDD and LVESD Z scores in all children with CCAVB were larger than in normal controls (LVEDD Z score 1.38 ± 1.80; LVESD Z score 0.64 ± 1.35). Both Z scores were larger when HR was lower. Both Z scores increased over time in children who met criteria for pacing, but did not change in non‐paced children. Physiologic pacing decreased both Z scores. SF of all children was normal and remained normal during follow‐up (0.39 ± 0.05 1st visit vs 0.39 ± 0.06 last visit).

Conclusions: We conclude that children with CCAVB have LV dilatation, which is progressive in children who met criteria for pacing. LV dilatation regressed by physiologic pacing. LV dilatation was larger when HR was lower. SF does not deteriorate over time. DCM occurs early in the disease and does not develop during childhood, not even in children with LV dilatation.
Cardiac Resynchronization Therapy:
Authors: LILLI ALESSIO , RICCIARDI GIUSEPPE , PORCIANI MARIA CRISTINA , PERINI ALESSANDRO PAOLETTI , PIERAGNOLI PAOLO , MUSILLI NICOLA , COLELLA ANDREA , PACE STEFANO DEL , MICHELUCCI ANTONIO , TURRENI FEDERICO , SASSARA MASSIMO , ACHILLI AUGUSTO , SERGE BAROLD S. , PADELETTI LUIGI
Published: October 2007

Aim:

Gender related differences in epidemiology, treatment, and prognosis of heart failure (HF) have been reported. We examined the sex influence in patients treated with cardiac resynchronization therapy (CRT).

Methods and Results:

Out of 334 consecutive HF patients (19.7% women) who underwent CRT, 195 patients reached clinical and echocardiographic evaluation at six and 12 months and were selected for analysis. A reduction in left ventricular (LV) end‐diastolic volume/m2 (EDVi) and end systolic volume/m2 (ESVi) was evident in the overall population at six months (P < 0.001) and from six to 12 months (P < 0.001). Compared to men, women showed significantly greater changes in LV volumes at mid (P < 0.05) and long‐term (P < 0.001) follow‐up and a significantly higher LV ejection fraction (EF) (40.8 ± 12.3 vs 34.1 ± 10.1, P < 0.01) at one year. Multiple regression analysis, including several demographic and clinical parameters, revealed that female gender is independently associated with greater reduction in LV ESVi.

At the 12‐month follow‐up, the proportion of responders (defined in terms of ESV reduction by at least 10%) was higher in women than in men (76.1% vs 59.3%, P < 0.05).

Conclusions:

CRT induced a gender specific LV remodeling response.
Experience of ICD Management at a UK Center:
Authors: KOA‐WING MICHAEL , WRIGHT IAN , PETERS NICHOLAS S. , DAVIES D. WYN , FRANCIS DARREL P. , KANAGARATNAM PRAPA
Published: October 2007

Background: It would be useful to identify patients at high risk of implantable cardioverter defibrillator (ICD) therapy via additional antiarrhythmic measures to minimize the morbidity of ICD therapies.

Objective: We assessed baseline characteristics for predictors of device therapy in a general ICD population. We also compared the likelihood of therapy delivery by replacement ICDs implanted for battery depletion with the original implants.

Methods: Clinical and ICD interrogation data from patients followed up at a UK center were analyzed looking for predictors of appropriate ICD therapy. Univariate and multivariate analysis was performed using Cox regression. We compared time to first appropriate therapy between first and second ICDs in patients who had undergone ICD replacement for battery depletion by log‐rank testing.

Results: One hundred and sixty‐one patients were studied (129 men, age 65.7 ± 12.9 years, follow‐up 908 ± 676 days). Appropriate therapy was delivered in 68 patients (42%). Univariate risk factors for appropriate ICD therapy were presentation with stable ventricular tachycardia (VT) (P = 0.0002), ischemic etiology (P = 0.03), tiered therapy programmed ICDs (P = 0.01), and beta‐blocker use (P = 0.001). Stable VT and beta blocker use were independent predictors of ICD therapy on multivariate analysis. Thirty‐three patients (20%) had at least one ICD replacement. Time to first appropriate therapy was no different between first and second ICD implants (P = 0.8).

Conclusion: Patients who present with cardiovascularly stable VT have a higher probability of receiving appropriate ICD therapy than those who do not. Following battery depletion of an original ICD, the replacement device is no less likely to administer therapy than the first.
Morphology of the RV Electrogram during LV Pacing is Related to the Hemodynamic Effect in Cardiac Resynchronization Therapy
Authors: VAN GELDER BERRY M. , BRACKE FRANK A. , MEIJER ALBERT , PILMEYER ART , PIJLS NICO H.J.
Published: October 2007

Background:

Biventricular (BiV) pacing and left ventricular (LV) pacing both improve LV function in patients with heart failure and LV dyssynchrony. We studied the hemodynamic effect of the atrioventricular (AV) interval and the associated changes in the right ventricular (RV) electrogram (EGM) during LV pacing and compared this with the hemodynamic effect of optimized sequential BiV pacing.

Methods:

In 16 patients with New York Heart Association (NYHA) class II to IV, sinus rhythm with normal AV conduction, left bundle branch block (LBBB), QRS > 130 ms, and optimal medical therapy, the changes in RV EGM during LV pacing with varying AV intervals were studied. The hemodynamic effect associated with these changes was evaluated by invasive measurement of LVdP/dtmax and compared with the result of optimized sequential BiV pacing in the same patient.

Results:

All patients showed electrocardiographic fusion during LV pacing. The morphology of the RV EGM showed changes in the RV activation that indicated a shift in the extent of fusion from LV pacing. These changes were associated with significant changes in LVdP/dtmax. Baseline LV dP/dtmax was 734 ± 177 mmHg/s, which increased to 927 ± 202 mmHg/s (P<0.0001) with optimized LV pacing and to 920 ± 209 mmHg/s (P<0.0001) with optimized sequential BiV pacing.

Conclusion:

The RV EGM is a proper indicator for intrinsic activation over the right bundle during LV pacing and reveals the transition to fusion in the RV EGM that is associated with a decrease in LVdP/dtmax. The hemodynamic effect of optimized LV pacing is equal to optimized sequential BiV pacing.
Maintenance of AV Synchrony in a Small Child Utilizing Two Pacemakers and the Triggered VVT Mode:
Authors: KIM JEFFREY J. , VALDES SANTIAGO O. , KERTESZ NAOMI J. , FRIEDMAN RICHARD A. , LEWELLEN MELISSA , DOMINO MELISSA , CANNON BRYAN C.
Published: October 2007

Infants and small children with atrioventricular (AV) nodal disease frequently require pacing in order to maintain an adequate heart rate. The maintenance of AV synchrony is physiologically optimal in this setting. Unfortunately, small size and congenital anomalies often preclude the placement of standard transvenous dual chamber pacing systems. We report the case of a small child with a pre‐existing dual chamber epicardial pacing system and subsequent ventricular lead dysfunction who underwent implantation of a new single chamber transvenous system which was programmed in VVT (triggered) mode in order to maintain AV synchrony.
Inappropriate Defibrillator Shocks from Depolarization—Repolarization Mismatch in a Patient with Hypertrophy Cardiomyopathy
Authors: KAPA SURAJ , CURWIN JAY H. , COYNE ROBERT F. , WINTERS STEPHEN L.
Published: October 2007

Despite wide use of dedicated bipolar sensing electrodes in implantable cardioverter‐defibrillator (ICD) systems, oversensing occasionally occurs, leading to unwarranted shocks or antitachycardia pacing. This case report highlights an individual with hypertrophic cardiomyopathy (HCM) who experienced inappropriate shocks from oversensing of repolarization electrograms (T‐waves). During the implantation procedure, no excessive T‐wave amplitudes were detected during sinus rhythm, ventricular pacing, or induced ventricular fibrillation. T‐wave oversensing leading to shocks only developed after maturation of the lead–tissue interface. An adequate safety margin for discrimination between ventricular electrograms and T‐waves could not be assured. Thus, insertion of a new dedicated pacing‐sensing electrode was required. The degree to which intracardiac repolarization signals may be heightened in patients with HCM has not been investigated systematically. However, a relative decrease in the ventricular electrogram amplitude without a concomitant decline of the intracardiac T‐wave amplitude appears to have led to the problem in this patient. Special caution in technique and device selection with a particular emphasis on T‐wave sensing may be prudent when ICDs are implanted in individuals with HCM. Additional programmable variables may also be beneficial in such cases.
Widely‐Split Double Potentials at the Pulmonary Vein Ostium in Patients with Atrial Fibrillation
Authors: KIM SUSAN S. , ROBERTS MICHAEL , BURKE MARTIN C. , KNIGHT BRADLEY P.
Published: October 2007

Left atrial muscle sleeves extending over the pulmonary veins are critical to the initiation of atrial fibrillation (AF) in some patients. This report describes two patients with paroxysmal AF who demonstrate widely‐split pulmonary vein (PV) double potentials at the pulmonary vein ostium during sinus rhythm. The response by the double potentials to PV isolation is also characterized. These cases emphasize the importance of recognizing unusual PV electrophysiology and using patient‐ and mechanism‐specific approaches to catheter ablation for AF.
Asystole Induced by Partial Seizures:
Authors: CARINCI VALERIA , BARBATO GAETANO , BALDRATI ANNA , DI PASQUALE GIUSEPPE
Published: October 2007

The clinical distinction between cardiovascular and epileptic causes of loss of consciousness is sometimes difficult, but becomes challenging when a primary epileptic seizure secondarily causes an asystole. Epilepsy can be correlated to severe bradycardia or asystole. The syndrome is called the ictal bradycardia syndrome. Ictal bradycardia and asystole have been implicated in the etiology of sudden unexpected death in epileptic patients (SUDEP). We present a case of traumatic syncope during an epileptic disorder ab esordio and we discuss the related literature.
Pacemaker Infection Secondary to Burkholderia Pseudomallei
Authors: ZAINAL ABIDIN IMRAN , SYED TAMIN SYAHIDAH , HUAT TAN LIAN , CHONG WEI PENG , AZMAN WAN
Published: October 2007

Infection is a relatively rare but devastating complication of intracardiac device implantation. Burkholderia pseudomallei is the organism which causes melioidosis, an endemic and lethal infection in the tropics. We describe a case of pacemaker infection secondary to Burkholderia pseudomallei, which was treated by explantation of the device and appropriate antimicrobial therapy.
Preserved Left Ventricular Ejection Fraction Following Atrioventricular Junction Ablation and Pacing for Atrial Fibrillation
Authors: CHEN LIN , HODGE DAVID , JAHANGIR ARSHAD , OZCAN CEVHER , TRUSTY JANE , FRIEDMAN PAUL , REA ROBERT , BRADLEY DAVID , BRADY PETER , HAMMILL STEPHEN , HAYES DAVID , SHEN WIN‐KUANG
Published: October 2007

Introduction: Right ventricular apical (RVA) pacing creates ventricular dyssynchrony and may compromise left ventricular ejection fraction (LVEF). The impact of RVA pacing in patients who have undergone atrioventricular junction (AVJ) ablation for atrial fibrillation (AF) is unclear. We sought to determine whether RVA pacing after AVJ ablation for patients with AF compromises LVEF in the short‐ or long‐term.

Methods/Results: We studied 286 patients with AF who underwent AVJ ablation and RVA pacing at our institution between 1990 and 2002. Patients were stratified into a short‐term follow‐up group (LVEF reassessed by echocardiography within a year after AVJ ablation, n = 134) and a long‐term group (LVEF reassessed after a year, n = 152). Among all 286 patients (mean follow‐up 20 months), we observed no change in mean LVEF after AVJ ablation and RVA pacing (48% before vs. 48% after, P = 0.42). Short‐term follow‐up patients had a statistically significant improvement in mean LVEF (46% before vs. 49% after, P = 0.03), whereas there was no statistically significant change in mean LVEF in long‐term follow‐up patients (49% before vs. 48% after, P = 0.37). Only 9% of short‐term patients, 15% of long‐term patients, and 1% of patients with baseline LVEF ≤ 40% experienced ≥10% absolute decrease in LVEF. Baseline LVEF > 40% was a multivariate predictor of LVEF decline.

Conclusions: RVA pacing after AVJ ablation does not compromise LVEF in the short‐ or long‐term for the vast majority of patients. Better predictors are needed to help us select patients for biventricular pacing after AVJ ablation.