bluuebunny/crossref_metadata_2025 huggingface dataset:
Controlled two-dimensional coated nanostructures for bulk thermoelectric composites
Authors: Zhang B. , He J. , Ji X. , Tritt Terry M. , Kumbhar Amar
Published: October 2006

The authors demonstrate herein a new route to introduce two-dimensional nanostructures into a bulk thermoelectric material using a hydrothermal coating technique. A very thin Pb0.75Sn0.25Se crystalline layer (typically about 30nm) is fabricated onto the surfaces of micron-sized Pb0.75Sn0.25Te seed particles. Compared to the conventional preparation of the nanocomposite thermoelectric materials, the salient advantage of this “coating” technique is that the authors are able to achieve a more homogenous dispersion of the nanostructures, which should subsequently result in more desirable effects on both the thermal and electrical transports via the direct control of the intergrain boundary.
Quantum chemical study of the initial surface reactions of HfO2 atomic layer deposition on the hydroxylated GaAs(001)-4×2 surface
Authors: Lu Hong-Liang , Xu Min , Ding Shi-Jin , Chen Wei , Zhang David Wei , Wang Li-Kang
Published: October 2006

Initial surface reaction mechanism for atomic layer deposition of HfO2 on the hydroxylated GaAs(001)-4×2 surface using HfCl4 and H2O as precursors is investigated using hybrid density functional theory. The reaction between HfCl4 and H2O with the hydroxylated GaAs(001)-4×2 surface consists of two half-reactions: (1) HfCl4 with GaAs–OH sites and (2) H2O with Hf–Cl sites. The two half-reactions proceed through the formation of stable chemisorbed states, resulting in high activation barriers of 17.1 and 17.6kcal∕mol for HCl formation, respectively. Additional energies are also needed to desorb the respective physisorbed states HCl from the substrate surfaces.
Photodissociation of acetaldehyde as a second example of the roaming mechanism
Authors: Houston P. L. , Kable S. H.
Published: October 2006

Product state distributions of the CO produced in the 308-nm photolysis of acetaldehyde show clear evidence of two dissociation mechanisms. One is attributed to the conventional transition state mechanism predicted by theory, with high rotational and translational energy of the CO and a pronounced v⊥J vector correlation. However, as much as 15% of the reaction flux proceeds via another pathway that produces low CO rotational and translational energy, very high CH
4
internal energy, and no correlation between the CO velocity and angular momentum vectors. The attributes of this channel are dynamically similar to the recently reported “roaming atom” mechanism in formaldehyde. We therefore speculate that the second pathway in acetaldehyde also occurs via a roaming mechanism in the CH
3
+ HCO exit channel that decays into the CH
4
+ CO channel.
Surface-induced structures in surfactant and polymer–surfactant systems: the potential for interesting surface dynamics
Authors: Penfold J.
Published: October 2006

From neutron reflectivity and other studies, a variety of interesting surface and interfacially-induced structures in surfactant and polymer–surfactant mixtures have been observed. These range from surface-induced micellisation, lamellar ordering at interfaces and the adsorption of polymer–surfactant complexes giving rise to layered structures at the interface. It has been observed that in many cases, these surface structures give rise to interesting and often unexplained surface visco-elastic properties. The combination of neutron spin echo and reflectivity techniques provides the potential for the opportunity to study the surface dynamics of such systems. In the context of the potential applications of inelastic neutron reflectivity, the need for further and more detailed investigations of surface dynamics in such systems are discussed.
Predictors of disability pension over a 10-year period for men and women
Authors: Albertsen Karen , Lund Thomas , Christensen Karl B. , Kristensen Tage S. , Villadsen Ebbe
Published: October 2006

Aims: The number of people leaving the labour market with a disability pension is high and knowledge regarding risk factors is limited. The aim of this study was to explore work- and non-work-related predictors of disability pension among men and women and to estimate to what extent the gender difference in retirement rate could be explained by factors in and outside work. Methods: A random sample of 5,940 employees registered in the Danish National Work Environment Cohort Study in 1995 was followed up with regard to labour market status in 2005 using the DREAM register, which contains data on all social transfer payments in the Danish population. Associations between disability pension and measures of ergonomic and psychosocial work environment, public employment, family status, and lifestyle were analysed by Cox regression and the difference in retirement rates adjusted separately for each group of variables. Results: The results showed (a) that both men and women had a higher risk of disability pension when they had work that involved standing or if they smoked; (b) that women in addition had a higher likelihood if they were public employees, had low job security, or low social support at work; (c) that the higher rate of disability pension among women compared with men could not be explained by work environmental factors, lifestyle, or family situation. Public employment was the single factor that explained most of the difference. Conclusions: Gender differences in exposures and predictors of disability pension were found, but few explanations of the higher rate of disability pension among women.
Design and implementation of a tool for translating SBML into the biochemical stochastic π-calculus
Authors: Eccher Claudio , Priami Corrado
Published: October 2006

Motivation: SBML is becoming a standard ‘de-facto’ to represent and store biological models. Although SBML is very useful in defining ways of exchanging and storing biological information, it is not formal enough to allow direct translation into non ambiguous formal representation languages to perform analysis and simulation of models. We here suggest to map SBML models into process calculi representations.

Results: We implemented and validated a tool that translates SBML descriptions into stochastic π-calculus specifications.

Availability: Source code is freely available for academic use by contacting the authors.

Contact:  cleccher@itc.it
sGAL: a computational method for finding surface exposed sites in proteins suitable for Cys-mediated cross-linking
Authors: Woolley G. Andrew , Lee En-shiun , Zhang Fuzhong
Published: October 2006

sGAL is a computer program designed to find pairs of sites suitable for introducing chemical cross-links into proteins. sGAL takes a protein structure file in PDB format as input, truncates each residue sequentially to its gamma side chain atom to mimic mutation to Cys, and calculates the exposed surface area of the gamma atom. The user then inputs the minimum and maximum lengths of the cross-linker. sGAL provides as output pairs of residues that would have exposed gamma atom separations that fall within this range. Furthermore, if a line joining the pair of gamma atoms contacts more than a given number of buried atoms, that pair is discarded. In this way, sites for which the protein would sterically interfere with cross-linking are avoided.

Availability:  ; (Surface Racer is also required see: ).

Contact:  awoolley@chem.utoronto.ca
hTERT expression in melanocytic lesions: an immunohistochemical study on paraffin‐embedded tissue
Authors: Fullen Douglas R. , Zhu Weijian , Thomas Dafydd , Su Lyndon D.
Published: October 2006

Background:  Telomerase plays a role in the immortalization of cells and carcinogenesis. Previous studies have yielded conflicting results on whether human telomerase RNA (hTER) expression differs in nevi, atypical nevi and melanomas using polymerase chain reaction‐based telomeric repeat amplification protocol or in situ hybridization assays. The aim of this study was to evaluate human telomerase reverse transcriptase (hTERT) staining in melanocytic lesions on paraffin‐embedded tissues.

Methods:  Paraffin‐embedded sections from 12 acquired nevi, seven dysplastic nevi, 11 Spitz nevi, eight primary invasive melanomas, and three metastatic melanomas were studied for staining intensity (0–3+) and percentage of labeled cells with anti‐hTERT.

Results:  hTERT staining was observed in most cells (>75%), in all but three lesions, and was of greater intensity in the nucleus, especially the nucleolus, compared with the cytoplasm. Spitz nevi tended to have weaker hTERT staining (mean = 1.7) compared with acquired nevi (mean = 2.2), dysplastic nevi (mean = 2.4), primary melanomas (mean = 2.4), or metastatic melanomas (mean = 3).

Conclusions:  Although telomerase activity was weaker in Spitz nevi, there was overlap with other nevi and primary invasive melanomas in our small series. Thus, hTERT expression does not appear to be a reliable adjunct to the histological diagnosis of primary melanocytic lesions.
Extensin over‐expression in Arabidopsis limits pathogen invasiveness
Authors: WEI GUO , SHIRSAT ANIL H.
Published: October 2006

The function of the cell wall protein extensin has been the subject of much speculation since it was first isolated over 40 years ago. In order to investigate the role of extensins in plant defence, we used the gain‐of‐function strategy to generate transgenic Arabidopsis plants over‐expressing the EXT1 extensin gene. These were infected with the virulent bacterial pathogen Pseudomonas syringae DC3000 and symptom development was monitored. Lesions on the transgenics were on average five‐fold smaller than those on the wild‐type, did not increase in area over the time period of infection, accumulated a small bacterial load and showed very little chlorosis outside the lesion boundary. By contrast, lesions on the wild‐type were large, spread to over 50% of the leaf area, continued to increase in size over the time course of the infection, accumulated a bacterial load 100‐fold higher than that found in the transgenics, and showed a large chlorotic area outside the lesion boundary. SEM of lesions showed no evidence of bacteria at the lesion boundary in the extensin‐over‐expressing transgenics, whereas bacteria were always seen at the lesion boundary on the wild‐type. Analysis of transgenics carrying an EXT1–GUS promoter–reporter fusion showed expression of GUS in a ring around the boundary of the lesion. Basal defences and signal transduction pathways involved in plant defence were not perturbed in the transgenics, as shown by the analysis of the expression of PR1 and PDF1.2 genes. These results show that extensin over‐expression limits pathogen invasiveness.
Enamel defects and ectopic eruption in a child with Usher syndrome and a cochlear implant
Authors: BALMER RICHARD , FAYLE STEPHEN A. F.
Published: October 2006

Background.  Usher syndrome is a genetic disorder consisting of progressive loss of vision and hearing.

Case Report.  The paper describes an 8‐year‐old girl with Usher syndrome type I who presented with generalized defects of the permanent dentition and ectopic eruption of the right maxillary first permanent molar. A cochlear implant had been fitted for her hearing loss, and the report reviews the implications of this device for dental treatment. The impacted first permanent molar was encouraged to erupt into the correct position by shaving the distal surface of the second primary molar.

Conclusion.  This is the first report to describe in detail an association between Usher syndrome and enamel defects.
Clinical judgement in the interpretation of evidence: a Bayesian approach
Authors: Harbison Jean
Published: October 2006

Aim. This paper presents an argument for the use of Bayesian reasoning in considering the value of evidence in making nursing judgements.

Background. Nursing has taken on board the drive towards evidence‐based practice. There has been little discussion, however, of how evidence should be interpreted. There is a growing interest in health care in the use of Bayesian reasoning for evidence interpretation, both in research and in clinical practice; as yet, there is a limited discussion in the literature of relevance to nursing.

Objectives. To provide a short tutorial in the application of Bayes rule to a clinical judgement. To discuss the implications for practice of adopting a Bayesian perspective.

Discussion. The relationship between evidence and clinical judgement is outlined. The need to accept uncertainty, and be equipped to deal adequately with this, is discussed: some basic ideas of probability are rehearsed. An outline of Bayesian reasoning is offered and a demonstration of the application of Bayes rule to a nursing judgement is presented.

Relevance to practice. A rationale for adopting a Bayesian perspective on evidence interpretation is offered: namely the changing context of practice, with the blurring of professional boundaries and the need to articulate judgements, the avoidance of error and the opportunity to identify the appropriate areas for investigation in nursing.
The provision of psychological therapy to people with intellectual disabilities: an investigation into some of the relevant factors
Authors: Mason J.
Published: October 2006

Background  Five factors are proposed as important in influencing the provision of psychological therapy to people with intellectual disabilities (IDs): the perceived effectiveness of psychological therapy, individual clinician competence, service resources (number of trained clinicians), the level of the client’s disability and the diagnostic overshadowing bias.

Method  A prospective questionnaire design was used. A survey style questionnaire was sent out to clinical psychologists (n = 412) and psychiatrists (n = 274) working in ID services in the UK. Responses were received from 133 psychologists and 90 psychiatrists.

Results  Perceived competence, the level of the client’s disability and the diagnostic overshadowing bias all appeared to be important factors. The perceived effectiveness of psychological therapy with this client group and service resources appeared less important than hypothesized.

Conclusion  Whereas the debates in research publications tend to focus on broad issues of effectiveness, clinicians themselves appear more concerned with their personal skill levels. The issue of the appropriateness of psychological therapies for people with more severe levels of disability remains largely unresearched.
Comparative phylogeography of eastern chipmunks and white‐footed mice in relation to the individualistic nature of species
Authors: ROWE KEVIN C. , HESKE EDWARD J. , PAIGE KEN N.
Published: October 2006

Palaeoecological studies have demonstrated that ecological communities as a whole did not remain stable throughout the climatic fluctuations of the Quaternary. The result is that long‐term associations of species cannot be inferred by contemporary associations in ecological communities. Therefore, the evolutionary significance of any contemporary ecological interactions among species and of the biotic community within which species have evolved also cannot be assumed from contemporary conditions. Comparative phylogeographic data provide a method to identify species within ecological communities that have shared biogeographic histories. We present an example of a long‐term association between populations of two mammalian species, eastern chipmunks (Tamias striatus) and white‐footed mice (Peromyscus leucopus), which are commonly associated with deciduous forest habitats. The distribution of mitochondrial DNA variation in T. striatus and P. leucopus from previously glaciated regions of the eastern United States support the hypothesis that, in at least part of their range, genetic lineages of the two species have expanded from similar population sources since the Last Glacial Maximum. In addition, the spatial concordance of genetic lineages of T. striatus and P. leucopus with the oak‐savannah forest formations of Wisconsin and Illinois, suggest that populations associated with this community colonized the area in association with a set of arboreal species that comprise their deciduous forest habitat.
Reports of birthweight by adolescents and their mothers: comparing accuracy and identifying correlates
Authors: Lucia Victoria C. , Luo Zhehui , Gardiner Joseph C. , Paneth Nigel , Breslau Naomi
Published: October 2006

Birthweight is associated with health outcomes throughout the lifespan. Official birthweight records are not always available, and researchers must rely on self‐reports for birthweight information. This study evaluates the accuracy of adolescent self‐reports of birthweight, using medical records as a standard, and compares it with maternal reports. It also examines potential correlates of accuracy. Respondents are 17‐year‐old adolescents and their mothers, who participated in a follow‐up study of randomly selected samples from newborn discharge lists (1983–85) of two major hospitals in south‐east Michigan. Nearly one‐quarter of the adolescents stated that they did not know their own birthweight, with males twice as likely as females to respond ‘don’t know’. In addition, self‐reports of birthweight among the remaining adolescents were inaccurate, and accuracy was inversely related to birthweight. While maternal reports of offspring’s birthweight are highly accurate across diverse subgroups of the population, adolescent self‐reports of birthweight are unlikely to be useful in medical research.
Relationships between air pollution and preterm birth in California
Authors: Huynh Mary , Woodruff Tracey J. , Parker Jennifer D. , Schoendorf Kenneth C.
Published: October 2006

Air pollution from vehicular emissions and other combustion sources is related to cardiovascular and respiratory outcomes. However, few studies have investigated the relationship between air pollution and preterm birth, a primary cause of infant mortality and morbidity. This analysis examined the effect of fine particulate matter (PM2.5) and carbon monoxide (CO) on preterm birth in a matched case–control study. PM2.5 and CO monitoring data from the California Air Resources Board were linked to California birth certificate data for singletons born in 1999–2000. Each birth was mapped to the closest PM monitor within 5 miles of the home address. County‐level CO measures were utilised to increase sample size and maintain a representative population. After exclusion of implausible birthweight–gestation combinations, preterm birth was defined as birth occurring between 24 and 36 weeks’ gestation. Each of the 10 673 preterm cases was matched to three controls of term (39–44 weeks) gestation with a similar date of last menstrual period. Based on the case’s gestational age, CO and PM2.5 exposures were calculated for total pregnancy, first month of pregnancy, and last 2 weeks of pregnancy. Exposures were divided into quartiles; the lowest quartile was the reference. Because of the matched design, conditional logistic regression was used to adjust for maternal race/ethnicity, age, parity, marital status and education.

High total pregnancy PM2.5 exposure was associated with a small effect on preterm birth, after adjustment for maternal factors (adjusted odds ratio [AOR] = 1.15, [95% CI 1.07, 1.24]). The odds ratio did not change after adjustment for CO. Results were similar for PM2.5 exposure during the first month of pregnancy (AOR = 1.21, 95% CI [1.12, 1.30]) and the last 2 weeks of pregnancy (AOR = 1.17, 95% CI [1.09, 1.27]). Conversely, CO exposure at any time during pregnancy was not associated with preterm birth (AORs from 0.95 to 1.00). Maternal exposure to PM2.5, but not CO, is associated with preterm birth. This analysis did not show differences by timing of exposure, although more detailed examination may be needed.
Absence of CD4+ T Cells Impairs Host Defence of Mice Infected with Fonsecaea pedrosoi
Authors: Teixeira de Sousa M. da Gloria , Ghosn E. E. B. , Almeida S. R.
Published: October 2006

Chromoblastomycosis is a human chronic, often debilitating, suppurative, granulomatus mycosis of the skin and subcutaneous tissues beginning after inoculation trauma. It occurs worldwide, but is more frequently observed in tropical countries such as Brazil. Some studies have focused on fungus–host interaction, showing a predominantly cell‐mediated immune response, with the activation of macrophages involved in fungus phagocytosis. Immunization with live conidia produced a high influx of CD4 T cells into the draining lymph node. The sensitized T cells proliferate in vitro when restimulated with specific antigen and preferentially produce IFN‐ γ. To better characterize the role played by T cells on the chromoblastomycosis infection we used mice deficient for CD4 and CD8. Data determined by CFU counts associated with decreased DTH and IFN‐γ production of infected mice clearly demonstrated that, during experimental F. pedrosoi infection, absence of CD4+ cells induces a more severe disease.
Antidepressants and suicidal behavior in bipolar disorder
Authors: McElroy Susan L , Kotwal Renu , Kaneria Rakesh , Keck Paul E
Published: October 2006

Patients with bipolar disorder are at very high risk for suicidal ideation, non‐fatal suicidal behaviors and suicide and are frequently treated with antidepressants. However, no prospective, randomized, controlled study specifically evaluating an antidepressant on suicidality in bipolar disorder has yet been completed. Indeed, antidepressants have not yet been shown to reduce suicide attempts or suicide in depressive disorders and may increase suicidal behavior in pediatric, and possibly adult, major depressive disorder. Available data on the effects of antidepressants on suicidality in bipolar disorder are mixed. Considerable research indicates that mixed states are associated with suicidality and that antidepressants, especially when administered as monotherapy, are associated with both suicidality and manic conversion. In contrast, growing research suggests that antidepressants administered in combination with mood stabilizers may reduce depressive symptoms in patients with bipolar depression. Further, the only prospective, long‐term study evaluating antidepressant treatment and mortality in bipolar disorder, although open‐label, found antidepressants and/or antipsychotics in combination with lithium, but not lithium alone, reduced suicide in bipolar and unipolar patients (Angst F, et al. J Affect Disord 2002: 68: 167–181). We conclude that antidepressants may induce suicidality in a subset of persons with depressive (and probably anxious) presentations; that this induction may represent a form of manic conversion, and hence a bipolar phenotype, and that lithium's therapeutic properties may include the ability to prevent antidepressant‐induced suicidality.
Prospective predictors of suicide and suicide attempts in 1,556 patients with bipolar disorders followed for up to 2 years
Authors: Marangell Lauren B , Bauer Mark S , Dennehy Ellen B , Wisniewski Stephen R , Allen Michael H , Miklowitz David J , Oquendo Maria A , Frank Ellen , Perlis Roy H , Martinez James M , Fagiolini Andrea , Otto Michael W , Chessick Cheryl A , Zboyan Holly A , Miyahara Sachiko , Sachs Gary , Thase Michael E
Published: October 2006

Objectives:  Bipolar disorders are associated with high rates of suicide attempts (SAs) and completions. Several factors have been reported to be associated with suicide in persons with bipolar disorder, but most studies to date have been retrospective and have not utilized multivariate statistics to account for the redundant prediction among variables submitted for analysis.

Methods:  This study examined the association between baseline clinical and demographic variables and subsequent SAs and completions through 2 years of follow‐up of participants in the Systematic Treatment Enhancement Program for Bipolar Disorder using a pattern‐mixture model.

Results:  Of the sample with complete data (n = 1,556), 57 patients (3.66%) experienced an SA or completion (CS). Several variables predicted suicidality (SA + CS) in this data set when considered alone, but after controlling for redundant prediction from other baseline characteristics, only history of suicide [odds ratio (OR) = 4.52, p < 0.0001] and percent days depressed in the past year (OR = 1.16, p = 0.036) were significantly associated with SAs and completions. A secondary analysis included a greater number of variables but a smaller sample size (n = 1,014). In the secondary analyses, only prior SAs predicted prospective suicidality (OR = 3.87, p = 0.0029).

Conclusions:  These results indicate that patients with bipolar disorder who present with a history of SAs are over four times as likely to have a subsequent SA or completion. Further studies are needed to evaluate and prevent future attempts in this high‐risk cohort.
Comparison of Romifidine and Medetomidine Pre‐medication in Propofol–Isoflurane Anaesthetised Dogs
Authors: Gómez‐Villamandos R. J. , Domínguez J. M. , Redondo J. I. , Martín E. M. , Granados M. M. , Ruiz I. , Santisteban J. M.
Published: October 2006

The objective of this paper was to evaluate romifidine as a pre‐medicant in dogs prior to propofol–isoflurane anaesthesia, and to compare it with medetomidine. For this, eight healthy dogs were anaesthetised. Each dog received three pre‐anaesthetic protocols: R40 (romifidine, 40 μg/kg, IV), R80 (romifidine, 80 μg/kg, IV) or MED (medetomidine, 10 μg/kg, IV). Induction of anaesthesia was delivered with propofol and maintained with isoflurane. The following variables were studied before sedative administration and 10 min after sedative administration: heart rate (HR), mean arterial pressure (MAP), systolic arterial pressure (SAP) and diastolic arterial pressure (DAP) and respiratory rate (RR). During maintenance, the following variables were recorded at 5‐min intervals: HR, MAP, SAD, DAP, arterial oxygen saturation (SpO2), end‐tidal CO2(EtCO2), end‐tidal concentration of isoflurane (EtISO) required for maintenance of anaesthesia and tidal volume (TV). Time to extubation, time to sternal recumbency and time to standing were also registered. HR and RR experimented a significantly decreased during sedation in all protocols respect to baseline values. Mean HR, MAP, SAP, DAP, SpO2, EtCO2, and TV during anaesthesia were similar for the three protocols. End tidal of isoflurane concentration was statistically similar for all protocols. Recovery time for R40 was significantly shorter than in R80 and MED. The studied combination of romifidine, propofol and isoflurane appears to be an effective drug combination for inducing and maintaining general anaesthesia in healthy dogs.
Effect of Seminal Plasma Fractions on Stallion Sperm Survival after Cooled Storage
Authors: Akcay E. , Reilas T. , Andersson M. , Katila T.
Published: October 2006

This study aimed to evaluate stallion sperm survival after 24 h of cooled storage in the presence of seminal plasma (SP) derived from the sperm‐rich fractions (SRF) or sperm‐poor fractions(SPF) of the ejaculate, without SP, or in the presence of SP from other stallions. Ejaculates were collected from four stallions using an automated phantom, which separated the semen into five cups. Centrifuged and washed spermatozoa from cup 2 (SRF) were mixed with skim milk extender to a concentration of 100 × 106 sperm/ml and then 1:1 (v/v) with SP from the stallion's own or another stallions’ second (SP‐SRF) or last cup (SP‐SPF). Skim milk extender (K) and skim milk extender supplemented with modified Tyrode's medium (KMT) were used as control treatments. After a 24‐h storage period in a transport container, spermatozoa were evaluated for motion characteristics and plasma membrane integrity by calcein acetoxymethyl (AM)/propidium iodide staining. The percentage of spermatozoa with intact plasma membranes after storage was lower in SP‐SRF than in SP‐SPF, and the highest in K (P < 0.05). Progressive motility (PMOT) was lower for sperm stored in SP‐SRF than for sperm stored in SP‐SPF (P < 0.05), but there was no significant difference in total motility (TMOT). Sperm stored in KMT (P < 0.05) registered the highest TMOT and PMOT percentages. Osmolarity was significantly higher and pH lower in K than in KMT or SP. Treatment with SP‐SPF from three stallions benefited the PMOT of sperm from one stallion. These preliminary findings suggest that SP from SRFs may be more harmful during storage than SP from SPFs. Removal of SP improves sperm survival in KMT extender, and exchanging SP between stallions seems to influence sperm survival.
EFFECTS OF TROLOX ON NERVE DYSFUNCTION, THERMAL HYPERALGESIA AND OXIDATIVE STRESS IN EXPERIMENTAL DIABETIC NEUROPATHY
Authors: Sharma Shyam S , Sayyed Sufyan G
Published: October 2006

Diabetic neuropathy is one of the most common complications of diabetes and oxidative stress has been implicated to play a major role in its pathophysiology.

In the present study, we targeted oxidative stress using trolox, an anti‐oxidant, in streptozotocin‐induced diabetic neuropathy in rats.

Compared with control rats, diabetic rats showed significant deficits in motor nerve conduction velocity (MNCV; 49.91 ± 1.94 vs 42.77 ± 1.39 m/s, respectively) and nerve blood flow (NBF; 107.98 ± 8.22 vs 38.9 ± 2.7 arbitarary perfusion units, respectively) after 8 weeks of diabetes. Tail flick latencies for cold and hot immersion tests were also significantly reduced in diabetic rats, indicating thermal hyperalgesia. These observations indicate development of diabetic neuropathy.

A significant decrease in the activity of anti‐oxidant enzymes (superoxide dismutase and catalase) and an increase in lipid peroxidation were observed in sciatic nerves from diabetic rats compared with age‐matched control rats. Alterations in the activity of anti‐oxidant enzymes and lipid peroxidation in diabetic rats indicate oxidative stress in diabetic neuropathy.

Two weeks treatment with trolox (10 and 30 mg/kg, i.p.) started on completion of the 6th week of diabetes significantly improved MNCV, NBF and inhibited thermal hyperalgesia. Trolox treatment also improved the activity of anti‐oxidant enzymes and inhibited lipid peroxidation in sciatic nerves of diabetic rats.

The results of the present study suggest the beneficial effects of trolox in experimental diabetic neuropathy.
Paleoenvironmental interpretations of Quaternary reef deposits based on comparisons of 10 selected modern and fossil larger foraminifera from the Ryukyu Islands, Japan
Authors: Fujita Kazuhiko , Shimoji Hiroaki , Nagai Koichi
Published: October 2006

Abstract  A new method for reconstructing depositional environments of larger foraminifera‐bearing limestones is proposed. First, depth and spatial distributions of empty tests of 10 foraminiferal taxa in a 1–2 mm size fraction were examined using 32 surface sediment samples collected from depths shallower than 200 m, located to the west of Miyako Island, Ryukyu Islands, northwest Pacific. Distributional ranges of empty tests in the 1–2 mm size fraction appear to be more limited than those including other size fractions in previous reports, partly because larger empty tests of each taxon are less easily transported than smaller ones. Multivariate analyses (Q‐mode cluster analysis and non‐metric multidimensional scaling ordination) based on binary (presence/absence) data of the 10 taxa delineate four sample groups, each of which corresponds to different depositional environments: nearshore zone/bay inlet; back‐reef to fore‐reef; outer shelf to shelf slope; and shelf slope distant from coral reefs. Next, these modern data were applied to reconstruct the depositional environment of a rock section distributed in the Shiratorizaki area (Irabu Island, Ryukyu Islands), which consists of larger foraminiferal limestone of the Pleistocene Ryukyu Group. Multivariate analyses were performed on the fossil plus the modern foraminiferal data to explore the possible relationship of the fossil associations with variations in modern associations, demonstrating that the fossil foraminiferal associations resemble the modern outer shelf associations. The modern analog technique was also applied to estimate paleobathymetry using fossil foraminiferal data. The results indicate that the section studied was deposited in outer shelf environments at depths between 53.5 and 98.6 m. These paleoenvironmental interpretations are consistent with previous studies based on sedimentary facies and the computer‐based expert system. The modern dataset and methods used in our work would be particularly useful for paleoenvironmental reconstructions of Quaternary reef and shelf carbonates along active margins of the northwest Pacific.
Impact of antenatal screening on the presentation of infants with congenital heart disease to a cardiology unit
Authors: Chew Colleen , Stone Sunita , Donath Sussan M , Penny Daniel James
Published: October 2006

Aim:  Antenatal diagnosis of congenital heart disease (CHD) facilitates prenatal treatment and optimal perinatal care. This has been demonstrated to improve perinatal mortality and morbidity in neonates with CHD. Thus, antenatal diagnosis of CHD is most likely to benefit patients who require surgery in early infancy. We aimed to examine the frequency of antenatal diagnosis in neonates presenting to The Royal Children’s Hospital severe CHD.

Methods:  Main outcome measures were antenatal diagnosis and whether the individual lesion would have been expected to be detected on a four‐chamber view or four‐chamber and outflow tract view during a routine obstetric anomaly ultrasound. Poisson regression was used to estimate the average trend over the study period.

Results:  A total of 610 patients met the inclusion criteria, of whom 164 had an antenatal diagnosis (26.8%). If routine ultrasound screening was ideal, we would have expected 63.9% of cases to be detected on four‐chamber view and 83.6% on four‐chamber and outflow tract view. Trend analysis demonstrated an annual rate of improvement of 9% in actual versus expected antenatal diagnosis of CHD. Malformation‐specific analysis showed that antenatal detection was the highest for double inlet/outlet ventricle (51.3%, 95% confidence interval 34.8–67.6%) and the lowest for simple transposition of the great arteries (15.6%, 95% confidence interval 9.0–24.5).

Conclusion:  Despite mass screening for congenital malformations in Victoria with routine antenatal ultrasounds, a large proportion of neonates with severe congenital heart disease still present without an antenatal diagnosis.
Oral baclofen in children with cerebral palsy: A double‐blind cross‐over pilot study
Authors: Scheinberg Adam , Hall Kate , Lam Lawrence T , O’Flaherty Stephen
Published: October 2006

Aim:  To assess the effectiveness of oral baclofen in reducing spasticity and improving function in children with cerebral palsy.

Methods:  A double‐blind, randomised cross‐over pilot study of oral baclofen versus placebo. Assessment tools included the Goal Attainment Scale, Pediatric Evaluation of Disability Inventory, Modified Tardieu Scale and parent questionnaire.

Results:  Fifteen children with mean age 7.4 years (SD = 2.7 years) and spastic or spastic/dystonic quadriplegia (Gross Motor Function Classification System Level IV or V) were enrolled. Children scored significantly better on the Goal Attainment Scale with baclofen compared with placebo (F(1,13) = 4.5, P = 0.05). There was no significant difference between baclofen and placebo for the Pediatric Evaluation of Disability Inventory or Modified Tardieu Scale. Parent questionnaire results are described.

Conclusion:  This pilot study demonstrates that oral baclofen has an effect beyond placebo in improving goal‐oriented tasks, such as transfers, in children with spastic quadriplegic cerebral palsy.
Spin on perinatal testicular torsion
Authors: Samnakay Naeem , Tudehope David , Walker Rosslyn
Published: October 2006

Abstract:  We describe a recent case of perinatal testicular torsion at our institution. The presentation, management and outcome of perinatal testicular torsion are quite different to testicular torsion in the general paediatric population. The literature describes a variety of management options for perinatal testicular torsion and these are briefly reviewed. In cases of unilateral perinatal testicular torsin, there is controversy over whether surgery to fix the contralateral testis is required, and if so, the appropriate timing for the surgery. A good understanding of the issues unique to perinatal torsion will facilitate appropriate counseling of parents of affected neonates.
Family matters: A twelve‐year‐old male with respiratory symptoms, cachexia and clubbing
Authors: MacLean Joanna E , Mahant Sanjay , Bitnun Ari , Read Stan , Capra Michael , Solomon Melinda
Published: October 2006

Abstract:  The presentation of HIV in children varies between developed and developing countries. In addition, the presentation in adolescents may differ from that in younger children. This report highlights a rare presentation and complication of HIV in children and emphasizes the importance of cultural competency when approaching children and families from different cultural backgrounds.
Heart valve calcifications in patients with end‐stage renal disease: Analysis for risk factors
Authors: TARRASS FAISSAL , BENJELLOUN MERYEM , ZAMD MOHAMED , MEDKOURI GHISLAINE , HACHIM KHADIJA , BENGHANEM MOHAMED GHARBI , RAMDANI BENYOUNES
Published: October 2006

Background:  The prevalence of valve calcification (VC) in end‐stage renal disease patients is high and information regarding risk factors is scarce. Our aims were to determine the prevalence of VC in our maintenance haemodialysis (HD) population and to examine some possible aetiologic factors for its occurrence.

Methods:  We studied 90 patients (47 women) on maintenance HD for more than 12 months. An M‐mode two‐dimensional echocardiogram was carried out to evaluate mitral, aortic VC and ventricular geometry. We calculated mean daily calcium intake for the phosphate intestinal chelaing in the previous year to echocardiogram date and also mean values from previous year of Ca, PO4, Ca × PO4, parathyroid hormone, lipide profile, nutritional and inflammatory marquers. Finally consumption of calcium and alfacalcidol was also noted.

Results:  Thirty‐six patients (40%) presented with VC. Patients with VC were older and showed higher levels of serum calcium (92.00 ± 7.54 vs 89.27 ± 6.86 mg/L, P = 0.04), phosphorus (69.70 ± 18.33 vs 44.90 ± 12.43 mg/L, P < 0.0001), Ca × P product (6164.97 ± 1797.64 vs 4024.70 ± 1066.40 mg2/L2, P < 0.0001) and poor ventricular geometry, as compared with patients without VC. Moreover, they required higher doses of alfacalcidol for treating secondary hyperparathyroidism (0.43 ± 0.60 vs 0.11 ± 0.46 µg/day, P < 0.0001).

Conclusion:  Findings of the present study are consistent with a role of altered calcium and phosphate metabolism in the pathogenesis of VC in HD patients.
Renal anaemia: Recent developments, innovative approaches and future directions for improved management (Review Article)
Authors: KERR PETER G
Published: October 2006

SUMMARY:  The morbidity, mortality and economic burden of chronic kidney disease (CKD) and associated anaemia are substantial. With the increasing numbers of patients who are likely to be affected in the future, approaches are required to improve anaemia management without increasing the burden on health‐care professionals. A multidisciplinary approach to treatment, where early initiation of erythropoiesis‐stimulating agents (ESA) is encouraged, may improve patient outcomes. Recent studies also suggest that the early use of iron therapy in patients with CKD not on dialysis may be associated with beneficial effects on haemoglobin levels. Another strategy to reduce the burden on health‐care providers is to simplify anaemia management by extending the administration interval of ESA. Indeed, recent studies have explored the efficacy of extending the administration interval of ESA in clinical practice in CKD patients on dialysis and not on dialysis. The ability to maintain haemoglobin levels within guideline ranges at extended administration intervals may improve patient care and reduce the workload of health‐care providers.
Epidermal growth factor receptor mutations and susceptibility to targeted therapy in lung cancer
Authors: AHMED Syed M. , SALGIA Ravi
Published: October 2006

Abstract:  According to 2002 estimates, 1.35 million people were diagnosed with and 1.18 million died of lung cancer worldwide. Recently, a new class of medications targeting signal transduction pathways has come into focus in the treatment of various malignancies. In lung cancer, the molecules gefitinib and erlotinib which target the intracellular kinase domain of the epidermal growth factor receptor (EGFR), cause significant tumour responses and, in the case of erlotinib, a survival benefit in patients with previously treated cancers. Responses were most pronounced in female non‐smokers with adenocarcinoma histology. These patients were found more likely to harbour mutations of the receptor kinase domain, including in‐frame deletions in exon 19 (such as deletions of codons 746–750) and point deletions in exon 21 (such as L858R). Other EGFR kinase domain mutations have been found to confer resistance (T790M) or differential susceptibility to erlotinib and gefitinib (E884K). Gene amplification of EGFR also may predict sensitivity, although the mechanism by which this occurs is unclear, because level of expression detected by immunohistochemistry has not been correlated with increased sensitivity. Phenotypic and genotypic epithelial to mesenchymal transition may be an indicator of resistance to EGFR kinase inhibitors. In this article, we review efforts that have been undertaken to identify genomic determinants of drug susceptibility to EGFR tyrosine kinase inhibitors, with particular focus on the role of gene mutations.
Antituberculosis drugs and hepatotoxicity
Authors: YEW Wing Wai , LEUNG Chi Chiu
Published: October 2006

Abstract:  Isoniazid, pyrazinamide and rifampicin have hepatotoxic potential, and can lead to such reactions during antituberculosis chemotherapy. Most of the hepatotoxic reactions are dose‐related; some are, however, caused by drug hypersensitivity. The immunogenetics of antituberculosis drug‐induced hepatotoxicity, especially inclusive of acetylaor phenotype polymorphism, have been increasingly unravelled. Other principal clinical risk factors for hepatotoxicity are old age, malnutrition, alcoholism, HIV infection, as well as chronic hepatitis B and C infections. Drug‐induced hepatic dysfunction usually occurs within the initial few weeks of the intensive phase of antituberculosis chemotherapy. Vigilant clinical (including patient education on symptoms of hepatitis) and biochemical monitoring are mandatory to improve the outcomes of patients with drug‐induced hepatotoxicity during antituberculosis chemotherapy. Some fluoroquinolones like ofloxacin/levofloxacin may have a role in constituting non‐hepatotoxic drug regimens for management of tuberculosis (TB) in the presence of hepatic dysfunction. Isoniazid administration is currently the standard therapy for latent TB infection. Rifamycins like rifampicin or rifapentine, alone or in combination with isoniazid, may also be considered as alternatives, pending accumulation of further clinical data. During treatment of latent TB infection, regular follow up is essential to ensure adherence to therapy and facilitate clinical monitoring for hepatic dysfunction. Monitoring of liver chemistry is also required for those patients at risk of drug‐induced hepatotoxicity.
Pulmonary tuberculosis presenting as community‐acquired pneumonia
Authors: LIAM Chong‐Kin , PANG Yong‐Kek , POOSPARAJAH Shyamala
Published: October 2006

Objective and background:  The aims of this study were to investigate the frequency of Mycobacterium tuberculosis as a cause of community‐acquired pneumonia (CAP) requiring hospitalization in Malaysia, and to define the clinical features of pulmonary tuberculosis (PTB) that distinguish it from non‐TB CAP.

Methods:  A prospective study was performed on consecutive non‐immunocompromised patients aged 12 years and older, who were hospitalized for CAP.

Results:  Of a total of 346 patients hospitalized for CAP, the aetiological agent was identified in 163 patients (47.1%). M. tuberculosis was isolated in 17 patients (4.9%). Multivariate analysis revealed that the following features were significantly associated with culture‐positive PTB: duration of symptoms of more than 2 weeks before hospital admission (odds ratio (OR) 25.10; 95% confidence interval (CI) 4.63–136.05; P < 0.001), history of night sweats (OR 5.43; 95% CI 1.10–26.79; P = 0.038), chest radiograph showing upper lobe involvement (OR 8.23; 95% CI 1.59–42.53; P = 0.012) or cavitary infiltrates (OR 19.41; 95% CI 2.94–128.19; P = 0.002), total white blood cell count on admission of 12 × 109/L or less (OR 6.28; 95% CI 1.21–32.52; P = 0.029) and lymphopenia (OR 4.73; 95% CI 1.08–20.85; P = 0.040).

Conclusion:  Mycobacterium tuberculosis was not an uncommon cause of CAP requiring hospitalization in Malaysia. A longer duration of symptoms, history of night sweats, upper lobe involvement, cavitary infiltrates, lower total white blood cell count and lymphopenia were predictive of PTB.
Chronic necrotizing pulmonary aspergillosis as a complication of pulmonary Mycobacterium avium complex disease
Authors: KOBASHI Yoshihiro , FUKUDA Minoru , YOSHIDA Kouichiro , MIYASHITA Naoyuki , NIKI Yoshihito , OKA Mikio
Published: October 2006

Objective and background:  To investigate the characteristic clinical features of chronic necrotizing pulmonary aspergillosis (CNPA) as a complication of pulmonary Mycobacterium avium complex (MAC) disease.

Methods:  Clinical analysis of nine cases without a history of old pulmonary tuberculosis in whom CNPA was found to be a complication during the follow‐up period for MAC disease.

Results:  The average duration from the diagnosis of pulmonary MAC disease to the diagnosis of CNPA was 36.0 months. Five patients received antituberculous therapy including clarithromycin for pulmonary MAC disease, but this treatment was ineffective in most. A positive culture for Aspergillus spp. from sputum and a bronchoscopic specimen and clinical evidence of a chronic infective process were recognized in all cases at the time of detection of CNPA. Serological fungal examinations for anti‐Aspergillus IgG antibody were initially negative and became positive in all cases during the follow‐up period of pulmonary MAC disease. The presence of CNPA surrounding the cavity previously caused by MAC was characterized by local thickening of the cavity with a fungus ball and the appearance of an infiltration shadow surrounding the cavity. In most of the cases, CNPA was at first treated with oral itriconazole and then with i.v. infusion of micafungin, but the clinical efficacy was generally poor.

Conclusion:  The results of this study showed that during the long follow‐up period of patients with pulmonary MAC disease it is important to not only carry out serological examinations, but also perform radiological examinations using chest CT.
Comparison of Natural and Dumon airway stents for the management of benign tracheobronchial stenoses
Authors: RYU Yon Ju , KIM Hojoong , YU Chang‐Min , CHOI Jae Chul , KWON Yong Soo , KIM Jhingook , SUH Soo Won
Published: October 2006

Objective and background:  To investigate the utility and safety of the ‘Natural stent’, a newly designed silicone airway stent, the authors compared clinical outcomes and complications in patients who underwent silicone airway stenting for the management of benign airway stenosis.

Methods:  The medical records of 94 patients requiring the placement of 100 airway stents (43 Dumon and 57 Natural) were retrospectively reviewed in a tertiary referral hospital.

Results:  Post‐tuberculous stenosis was the leading indication for airway stenting (74%), followed by post‐intubation stenosis (21%). After intervention, dyspnoea improved in patients who underwent Dumon (90%) and Natural (86%) stenting. After stabilizing dyspnoea, stents could be successfully removed in half of the patients who underwent Dumon (54%) or Natural (49%) stenting. During a 42‐month follow‐up period, complication rates were similar in patients who underwent Dumon or Natural stenting.

Conclusion:  Natural airway stent was as effective and safe as Dumon stent for the management of benign tracheobronchial stenoses.