bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation of precise plastid deletion mutants by homology‐based excision: a resource for site‐directed mutagenesis, multi‐gene changes and high‐throughput plastid transformation
Authors: Kode Vasumathi , Mudd Elisabeth A. , Iamtham Siriluck , Day Anil
Published: April 2006

We describe a simple and efficient homology‐based excision method to delete plastid genes. The procedure allows one or more adjacent plastid genes to be deleted without the retention of a marker gene. We used aadA‐based transformation to duplicate a 649 bp region of plastid DNA corresponding to the atpB promoter region. Efficient recombination between atpB repeats deletes the intervening foreign genes and 1984 bp of plastid DNA (co‐ordinates 57 424–59 317) containing the rbcL gene. Only five foreign bases are present in ΔrbcL plants illustrating the precision of homology‐based excision. Sequence analysis of non‐functional rbcL‐related sequences in ΔrbcL plants indicated an extra‐plastidic origin. Mutant ΔrbcL plants were heterotrophic, pale‐green and contained round plastids with reduced amounts of thylakoids. Restoration of autotrophy and leaf pigmentation following aadA‐based transformation with the wild‐type rbcL gene ruled out mutations in other genes. Excision and re‐use of aadA shows that, despite the multiplicity of plastid genomes, homology‐based excision ensures complete removal of functional aadA genes. Rescue of the ΔrbcL mutation and autotrophic growth stabilizes transgenic plastids in heteroplasmic transformants following antibiotic withdrawal, enhancing the overall efficiency of plastid transformation. Unlike the available set of homoplasmic knockout mutants in 25 plastid genes, the rbcL deletion mutant isolated here is readily transformed with the efficient aadA marker gene. This improvement in deletion design facilitates advanced studies that require the isolation of double mutants in distant plastid genes and the replacement of the deleted locus with site‐directed mutant alleles and is not easily achieved using other methods.
The burden of disease in Zimbabwe in 1997 as measured by disability‐adjusted life years lost
Authors: Chapman Glyn , Hansen Kristian S. , Jelsma Jennifer , Ndhlovu Chiratidzo , Piotti Bruno , Byskov Jens , Vos Theo
Published: April 2006

Objective  To rank health problems contributing most to the burden of disease in Zimbabwe using disability‐adjusted life years as the population health measure.

Methods  Epidemiological information was derived from multiple sources. Population size and total number of deaths by age and sex for the year 1997 were taken from a nationwide census. The cause of death pattern was determined based on data from the Vital Registration System, which was adjusted for under‐reporting of human immunodeficiency virus (HIV) and reallocation of ill‐defined causes. Non‐fatal disease figures were estimated based on local disease registers, surveys and routine health service data supplemented by estimates from epidemiological studies from other settings if no Zimbabwean sources were available. Disease and public health experts were consulted about the identification of the best possible sources of information, the quality of these sources and data adjustments made.

Results  From the information collected, HIV infection emerged as the single most serious public health problem in Zimbabwe responsible for 49% of the total disease burden. A quarter of the total burden of disease was attributed to morbidity rather than premature mortality. The share of the disease burden was similar in females and males.

Conclusion  Using local sources of information to a large extent, it was possible to develop plausible estimates of the size and the relative significance of the major health problems in Zimbabwe. The disease pattern of Zimbabwe differed substantially from regional estimates for sub‐Saharan Africa justifying the need for countries to develop their own burden of disease estimates.
The economic impact of visceral leishmaniasis on households in Bangladesh
Authors: Anoopa Sharma D. , Bern Caryn , Varghese Beena , Chowdhury Rajib , Haque Rashidul , Ali Mustakim , Amann Josef , Ahluwalia Indu B. , Wagatsuma Yukiko , Breiman Robert F. , Maguire James H. , McFarland Deborah A.
Published: April 2006

Objectives  To explore current patterns of diagnosis and treatment, quantify household economic impact and identify household strategies to cover the costs of visceral leishmaniasis (VL) care in rural Bangladesh.

Method  Structured interviews with 113 VL patients from 87 households documenting all provider visits and expenditures for health care for VL, and the ways in which the expenditures were covered.

Results  Patients paid a median of 7 visits to six different providers before beginning VL treatment. All visited the subdistrict government hospital at least once. While health care, including antileishmanial drug therapy, is officially available free of charge at government facilities, 79% of patients reported making informal payments for provider access, diagnostics and drug administration; only 14% of patients received their full drug course from this source. For the 58% of patients who purchased the full treatment course, drug cost constituted 34% of direct expenditure. Median direct expenditure for one VL patient was US$87 and median income lost was $40; median total expenditure was 1.2 times annual per capita income of our study population. Households employed multiple coping strategies to cover expenditures, most commonly sale or rental of assets (62%) and taking out loans (64%).

Conclusions  Visceral leishmaniasis treatment causes a major economic burden in affected families. Control strategies for VL should facilitate timely, affordable diagnosis and treatment of patients to decrease the infection reservoir and to alleviate the economic burden of VL on households.
The indoor use of plastic sheeting pre‐impregnated with insecticide for control of malaria vectors
Authors: Diabate A. , Chandre F. , Rowland M. , N'guessan R. , Duchon S. , Dabire K. R. , Hougard J.‐M.
Published: April 2006

Objective  To evaluate the efficacy of permethrin‐treated plastic sheeting (ITPS) applied as a lining to the ceiling or walls of rooms against pyrethroid‐susceptible and pyrethroid‐resistant Anopheles gambiae.

Method  Overnight tests were carried out in veranda‐trap experimental huts in Vallée du Kou, where two molecular forms of A. gambiae, S and M, occur. The S form is mostly pyrethroid resistant due to the kdr mechanism, and the M form is mostly kdr susceptible. A variety of ITPS covered surfaces were tested, ranging from ceiling only to all walls plus ceiling covered.

Results  ITPS had a major effect on the mortality of mosquitoes, the proportion killed being dependent upon the surface area covered. Homozygotes for kdr resistance showed lower rates of mortality than did heterozygotes or homozygotes for susceptibility. Deterred entry of mosquitoes and inhibition of blood feeding were also correlated with surface area covered. The mode of action and efficacy of ITPS seems to bear closer resemblance to that induced by indoor residual spraying (IRS) than to that induced by insecticide‐treated nets.

Conclusions  ITPS might be conceived as being equivalent to long‐lasting or permanent IRS but without some of the operational constraints normally associated with spraying. High coverage of ITPS could potentially have a mass population effect on mosquitoes and give rise to long‐term community protection against malaria. A phase III trial is justified to assess the acceptability of ITPS and its efficacy against malaria.
Post‐abortion care and voluntary HIV counselling and testing – an example of integrating HIV prevention into reproductive health services
Authors: Rasch Vibeke , Yambesi Fortunata , Massawe Siriel
Published: April 2006

Objective  To assess the acceptance and outcome of voluntary HIV counselling and testing (VCT) among women who had an unsafe abortion.

Method  706 women were provided with post‐abortion contraceptive service and offered VCT. We collected data on socioeconomic characteristics and contraceptive use and determined the HIV status of those who accepted VCT. Using a nested case–control design, we compared women who accepted HIV testing with women who did not. To study the association between socioeconomic factors, HIV testing acceptance and condom use in more detail, we did stratified analyses based on age and marital status.

Results  58% of the women who had an unsafe abortion accepted HIV testing. Women who earned an income were more likely to accept testing than housewives. Women who accepted testing were more likely to accept using a condom. The HIV prevalence rate was 19% among single women aged 20–24 years and 25% among single women aged 25–45 years.

Conclusion  HIV testing and condoms were accepted by most women who had an unsafe abortion. The poor reproductive health of these women could be improved by good post‐abortion care that includes contraceptive counselling, VCT and condom promotion.
Platelet gel and fibrin sealant reduce allogeneic blood transfusions in total knee arthroplasty
Authors: Everts P. A. M. , Devilee R. J. J. , Brown Mahoney C. , Eeftinck‐Schattenkerk M. , Box H. A. M. , Knape J. T. A. , Van Zundert A.
Published: April 2006

Background:  Total knee arthroplasty (TKA) is often associated with a considerable amount of post‐operative blood loss, necessitating the transfusion of allogeneic blood, which can add to the complications. Optimization of strategies to reduce the need for blood transfusion is desired. This study was designed to evaluate the efficacy of autologous platelet gel and fibrin sealant in unilateral TKA.

Methods:  Consecutive patients were operated on and assigned to the study and control groups. Study group patients (n = 85) were operated on according to our standard TKA protocol, with the application of autologous platelet gel and fibrin sealant on the wound tissues at the end of surgery. Eighty patients were operated on according to the same protocol, but without the use of platelet gel and fibrin sealant, and served as the control group. All blood transfusions, occurrence of wound leakage, wound healing disturbances and incidences of post‐operative infections were recorded.

Results:  Patients in the treatment group had a significantly higher post‐operative haemoglobin level (11.3 vs. 8.9 g/dl, respectively) and a decreased need for allogeneic blood products (0.17 vs. 0.52 units, respectively) than those in the control group (P < 0.001). The incidences of wound leakage and wound healing disturbance were significantly less (P < 0.001) in patients managed with platelet gel and fibrin sealant. Four patients in the control group, who received blood products, developed wound infection. The hospital stay was decreased by 1.4 ± 1.5 days for patients in the treatment group (P < 0.001).

Conclusion:  Peri‐operatively applied platelet gel and fibrin sealant may reduce the incidence of allogeneic blood transfusions and complications associated with TKA.
To eject or to abandon? Life history traits of hosts and parasites interact to influence the fitness payoffs of alternative anti-parasite strategies
Authors: Servedio M. R. , Hauber M. E.
Published: April 2006

Hosts either tolerate avian brood parasitism or reject it by ejecting parasitic eggs, as seen in most rejecter hosts of common cuckoos, Cuculus canorus, or by abandoning parasitized clutches, as seen in most rejecter hosts of brown-headed cowbirds, Molothrus ater. What explains consistent variation between alternative rejection behaviours of hosts within the same species and across species when exposed to different types of parasites? Life history theory predicts that when parasites decrease the fitness of host offspring, but not the future reproductive success of host adults, optimal clutch size should decrease. Consistent with this prediction, evolutionarily old cowbird hosts, but not cuckoo hosts, have lower clutch sizes than related rarely- or newly parasitized species. We constructed a mathematical model to calculate the fitness payoffs of egg ejector vs. nest abandoner hosts to determine if various aspects of host life history traits and brood parasites’ virulence on adult and young host fitness differentially influence the payoffs of alternative host defences. These calculations showed that in general egg ejection was a superior anti-parasite strategy to nest abandonment. Yet, increasing parasitism rates and increasing fitness values of hosts’ eggs in both currently parasitized and future replacement nests led to switch points in fitness payoffs in favour of nest abandonment. Nonetheless, nest abandonment became selectively more favourable only at lower clutch sizes and only when hosts faced parasitism by a cowbird- rather than a cuckoo-type brood parasite. We suggest that, in addition to evolutionary lag and gape-size limitation, our estimated fitness differences based on life history trait variation provide new insights for the consistent differences observed in the anti-parasite rejection strategies between many cuckoo- and cowbird-hosts.
Successful caspofungin treatment of multidrug resistant Candida parapsilosis septicaemia in an extremely low birth weight neonate
Authors: Yalaz Mehmet , Akisu Mete , Hilmioglu Suleyha , Calkavur Sebnem , Cakmak Bilin , Kultursay Nilgun
Published: April 2006

Candida septicaemia with multidrug resistance is an uncommon event in preterm neonates. We present an extremely low birth weight infant (gestational age of 27 weeks, birth weight of 980 g) who developed congenital Candida parapsilosis septicaemia. Because the fungus was resistant both to amphotericin B and fluconazole, caspofungin was chosen for therapy. The fungus was successfully eradicated without any clinical or laboratory adverse effects.
Onychomycosis in Lebanon: a mycological survey of 772 patients
Authors: El Sayed Fouad , Ammoury Alfred , Haybe Rita Feghaly , Dhaybi Rola
Published: April 2006

Accurate diagnosis of onychomycosis is based on clinical findings, direct microscopic investigation and mycological culture. If the diagnosis is not confirmed by culture and improvement does not occur, it is impossible to tell whether this represents treatment failure or an initial incorrect diagnosis. The aim of this study was to identify the major organisms involved in onychomycosis with emphasis on the importance of culture in treating onychomycosis. The study was performed at the Lebanese University, Beirut, Lebanon over a 5‐year period (2000–2004). Clinically suspected patients were referred to our mycology laboratory for KOH test and culture. The study included 772 patients (520 women, 252 men). Cultures were positive in 54.3% of cases (predominantly male). The ratio of onychomycosis in toenails/fingernails was 1.9. In toenails, dermatophytes were found in 77.1% of cases, Candida in 18.9% and moulds in 4%. In fingernails, Candida was found in 81% of cases, dermatophytes in 18.1% and moulds in 0.9%. The most commonly isolated dermatophytes were Trichophyton mentagrophytes (36%), T. rubrum (27.5%) and T. tonsurans (26%). Pathogens involved in onychomycosis change according to each geographical area. Therefore, treatments should be based on studies carried out in the same region.
Characterisation of the anticryptococcal effect of the FC‐1 toxin produced by Filobasidium capsuligenum
Authors: Keszthelyi A. , Ohkusu M. , Takeo K. , Pfeiffer I. , Litter J. , Kucsera J.
Published: April 2006

The basidiomycetous yeast Filobasidium capsuligenum produces a killer toxin (FC‐1) which is highly effective against the opportunistic fungal pathogen Cryptococcus neoformans. The aim of this work was to study the effect of the toxin on C. neoformans cells. The sensitivities of strains representing eight molecular subtypes (VNI–IV and VGI–IV) of the C. neoformans species complex, and of an additional 50 clinical and environmental isolates were determined. Analysis of cellular DNA by laser scanning cytometry and fluorescein isothiocyanate (FITC) staining of the toxin‐treated cells revealed that the killing mechanism of FC‐1 is neither cell cycle‐ nor cell wall biosynthesis‐dependent; rather it may act as an ionophoric protein that disrupts the cytoplasmic membrane function. The competition assay results suggest that β‐1,6‐glucan in the cell wall may provide the binding site for the killer protein. This anticryptococcal toxin has the potential to be applied as a therapeutic agent for the treatment of cryptococcosis.
Multiple viral hepatitis in injection drug users and associated risk factors
Authors: Reimer Jens , Lorenzen Juergen , Baetz Bernhard , Fischer Benedikt , Rehm Juergen , Haasen Christian , Backmund Markus
Published: April 2006

Background:  While infections due to hepatitis B virus (HBV) and hepatitis C virus (HCV) have been well‐studied in injection drug users (IDUs), hepatitis A virus (HAV) infection and coinfection with multiple hepatitis viruses have received less attention.

Methods:  Hepatitis serology as well as sociodemographic and drug‐related parameters were explored in patients (n = 1512) admitted for opiate detoxification.

Results:  Antibodies to HAV were positive in 57.7%, to HBV in 53.0%, and to HCV in 75.0% of the sample. Lack of any hepatic marker was reported in 11.2%; one marker was positive in 24.7%; two markers were positive in 31.2%; and all markers were positive in 32.9%. In patients with one positive marker, 58.8% had had exposure to HCV, and 27% had exposure to HAV. In patients with two positive markers, 46.7% were HAV/HCV and 41.8% HBV/HCV antibody positive. Presence of HBV and HCV antibodies was associated with older age, longer duration of (i.v.) heroin use, and a higher number of rehabilitation treatment episodes (anova), current coconsumption of cocaine was associated with presence of antibodies to either HAV, HBV, and HCV.

Conclusions:  Coinfection with hepatic viruses is highly relevant in IDUs, although HAV does not necessarily share the same risk factors relevant for HBV or HCV transmission. The need for outreach vaccination programs is emphasized for HAV and HBV in the target population. Primary prevention should be implemented before initiation or at early stages of a drug career. Epidemiology and transmission of HAV in IDUs requires further research.
Overexpressed cyclo‐oxygenase‐2 in the background liver is associated with the clinical course of hepatitis C virus‐related cirrhosis patients after curative surgery for hepatocellular carcinoma
Authors: Morinaga Soichiro , Tarao Kazuo , Yamamoto Yuji , Nakamura Yoshiyasu , Rino Yasushi , Miyakawa Kaoru , Ohkawa Shinichi , Akaike Makoto , Sugimasa Yukio , Takemiya Shoji
Published: April 2006

Background: The probable role of cyclo‐oxygenase‐2 (COX‐2) in the development of hepatocellular carcinoma (HCC) in patients with chronic liver diseases has been accepted to be relevant. The purpose of the present study was to determine whether overexpressed COX‐2 in the background liver affects the clinical course of hepatitis C virus (HCV)‐related cirrhosis patients after curative surgery for HCC.

Methods: Twenty‐nine clinical stage I HCC patients with HCV‐related cirrhosis, who underwent curative surgery, were enrolled in the present study (22 men and seven women, age range 53–73 years; follow‐up period; range 22–159 months, median 61 months). The COX‐2 expression in the cirrhotic liver was examined by immunohistochemistry using the avidin–biotin–peroxidase complex technique on paraffin‐embedded formalin‐fixed tissue. The COX‐2 expression was scored, then correlated with monitored alanine aminotransferase (ALT) levels during the follow‐up period after surgery, response to alternative therapy aiming to improve elevated ALT levels, and recurrence/survival after surgery.

Results: The COX‐2 expression scores were significantly higher in the high‐ALT group than in the low‐ALT group (Mann–Whitney,P = 0.010), and were significantly higher in non‐responders to the alternative therapy than in responders (Mann–Whitney,P = 0.028). The higher COX‐2 expression in the cirrhotic liver was the significant independent risk factor for residual liver recurrence (Cox multivariate analysis,P = 0.014), but not for survival.

Conclusions: Overexpressed COX‐2 in the background liver may play an important role in prolonged acceleration of necroinflammation, resistance to the alternative therapy, and recurrence/new development of HCC in HCV‐related cirrhosis patients.
Modified technique of high‐resolution ultrasonography of the normal cervical esophagus
Authors: Mateen Mohammed A , Kaffes Arthur John , Sriram Parupudi VJ , Rao Guduru V , Reddy D Nageshwar
Published: April 2006

Background and Aim:  To study a modified technique of neck ultrasound for the visualization of cervical esophagus using a high‐resolution and high frequency linear transducer in normal subjects.

Methods:  Consecutive control subjects were patients who underwent abdominal sonography for other diseases and had no past or current history of dysphagia or esophageal disorders. The thyroid gland was used as a transducer window to obtain images. We used a slightly flexed neck position with the head turned 45 degrees to the opposite side while scanning the neck on either side.

Results:  One‐hundred subjects were scanned and their age range was 10–74 years (male : female ratio 1:1). In 36% of cases it was difficult to visualize the right lateral 2/3rd in the traditional scanning position of the neck. This improved to 2% with the modified neck position. All patients had the left window visualized with both neck positions. The transverse diameter, anterior‐posterior diameter and wall thickness measures were all significantly greater with the modified technique. All patients tolerated the procedure with no reported discomfort.

Conclusions:  This modified technique provides superior views of the cervical esophagus, particularly from the right window, in almost all patients. Normal parameters using ultrasound have now been established.
Threshold elemental ratios of carbon and phosphorus in aquatic consumers
Authors: Frost Paul C. , Benstead Jonathan P. , Cross Wyatt F. , Hillebrand Helmut , Larson James H. , Xenopoulos Marguerite A. , Yoshida Takehito
Published: April 2006

Inadequate supply of one or more mineral elements can slow the growth of animal consumers and alter their physiology, life history and behaviour. A key concept for understanding nutrient deficiency in animals is the threshold elemental ratio (TER), at which growth limitation switches from one element to another. We used a stoichiometric model that coupled animal bioenergetics and body elemental composition to estimate TER of carbon and phosphorus (TERC:P) for 41 aquatic consumer taxa. We found a wide range in TERC:P (77–3086, ratio by atoms), which was generated by interspecific differences in body C : P ratios and gross growth efficiencies of C. TERC:P also varied among aquatic invertebrates having different feeding strategies, such that detritivores had significantly higher threshold ratios than grazers and predators. The higher TERC:P in detritivores resulted not only from lower gross growth efficiencies of carbon but also reflected lower body P content in these consumers. Supporting previous stoichiometric theory, we found TERC:P to be negatively correlated with the maximum growth rate of invertebrate consumers. By coupling bioenergetics and stoichiometry, this analysis revealed strong linkages among the physiology, ecology and evolution of nutritional demands for animal growth.
Predator biodiversity strengthens herbivore suppression
Authors: Snyder William E. , Snyder Gretchen B. , Finke Deborah L. , Straub Cory S.
Published: April 2006

Species diversity at lower trophic levels generally improves ecosystem functioning. However, the impact of greater predator diversity on herbivore regulation is uncertain because predator species both compete with and prey on each other. In a large‐scale field experiment we examined the relationship between predator species diversity and the suppression of two herbivores, green peach and cabbage aphids, on collard plants. We show that, for both aphid species, the strength of herbivore suppression increased with higher predator biodiversity. Greater resource exploitation by predators in diverse communities generally led to improved predator survivorship and reproduction. Herbivore population size was negatively correlated with plant biomass, providing evidence that greater aphid suppression leads to improved plant growth. Our study suggests a harmonious relationship between predator conservation and herbivore control, and a relatively weak role for predator interference, within this community.
Working on educational research methods with masters students in an international online learning community
Authors: Hudson Brian , Owen David , Veen Klaas van
Published: April 2006

In this paper we discuss the background to this study in the development of the international MSc e‐Learning Multimedia and Consultancy. The aims of the study focus on the conditions for achieving communication, interaction and collaboration in open and flexible e‐learning environments. We present our theoretical framework that has informed the design of programme as a whole which is based on a socio‐constructivist perspective on learning. Our research is placed within an action research framework and we outline our position within the critical or emancipatory tradition and also our standpoint on the use of ICT in education. We discuss the design of the programme and also our pedagogical approach and describe in detail the particular context for this study. We report on the student experience of being learners on this module, their perceptions of what they have gained most from learning from and with each other and their responses to the various ways in which ‘scaffolding’ has been designed and implemented by the tutors. Finally we offer some reflections on the conditions for achieving well‐orchestrated interdependence in open and flexible e‐learning environments.
Prosodic Knowledge Affects the Recognition of Newly Acquired Words
Authors: Shatzman Keren B. , McQueen James M.
Published: April 2006

An eye-tracking study examined the involvement of prosodic knowledge—specifically, the knowledge that monosyllabic words tend to have longer durations than the first syllables of polysyllabic words—in the recognition of newly learned words. Participants learned new spoken words (by associating them to novel shapes): bisyllables and onset-embedded monosyllabic competitors (e.g., baptoe and bap). In the learning phase, the duration of the ambiguous sequence (e.g., bap) was held constant. In the test phase, its duration was longer than, shorter than, or equal to its learning-phase duration. Listeners' fixations indicated that short syllables tended to be interpreted as the first syllables of the bisyllables, whereas long syllables generated more monosyllabic-word interpretations. Recognition of newly acquired words is influenced by prior prosodic knowledge and is therefore not determined solely on the basis of stored episodes of those words.
Looking Deathworthy
Authors: Eberhardt Jennifer L. , Davies Paul G. , Purdie-Vaughns Valerie J. , Johnson Sheri Lynn
Published: April 2006

Researchers previously have investigated the role of race in capital sentencing, and in particular, whether the race of the defendant or victim influences the likelihood of a death sentence. In the present study, we examined whether the likelihood of being sentenced to death is influenced by the degree to which a Black defendant is perceived to have a stereotypically Black appearance. Controlling for a wide array of factors, we found that in cases involving a White victim, the more stereotypically Black a defendant is perceived to be, the more likely that person is to be sentenced to death.
Antimicrobial defence mechanisms of the human parotid duct
Authors: Kutta H. , May J. , Jaehne M. , Münscher A. , Paulsen F. P.
Published: April 2006

The parotid duct transports saliva from the gland into the oral cavity. However, its immune response properties, along with the secretion and moistening principles of the duct, have not yet been fully investigated. These properties may play an important role in protecting the parotid gland from infection and also prevent development of sialodocholithiasis, as the parotid duct – in contrast to the submandibular salivary duct – is often free of duct concrements. Up to now, only the parotid gland has been investigated, without regard to its duct. The present study analyses the structures of the parotid duct in their relations to antimicrobial defence mechanisms and rheological properties. Investigations were performed on 23 parotid ducts using histological, histochemical and immunohistochemical methods. Epithelial and goblet cells of the parotid duct synthesize a complex mucous layer that covers the epithelium. The viscosity is influenced by secreted mucins and TFF peptides. This layer contains carbohydrates including N‐acetyl‐glucosamine, N‐acetyl‐galactosamine, galactose, mannose, fucose and sialic acids. The lamina propria contains granulocytes, T lymphocytes and macrophages. IgA, produced by plasma cells in the subepithelial layer, is frequently integrated in the secretory product. Synthesized mucins, TFF peptides, carbohydrates and immunoglobulins form a complex layer that can be expected to prohibit infection and enables salivary flow. Our study demonstrates that the steady secretion of the parotid gland, together with the ductal cellular and biochemical immune protection system, is likely to thwart ascending infections in the parotid duct and gland.
Vitamin E protected cultured cortical neurons from oxidative stress‐induced cell death through the activation of mitogen‐activated protein kinase and phosphatidylinositol 3‐kinase
Authors: Numakawa Yumiko , Numakawa Tadahiro , Matsumoto Tomoya , Yagasaki Yuki , Kumamaru Emi , Kunugi Hiroshi , Taguchi Takahisa , Niki Etsuo
Published: April 2006

The role of vitamin E in the CNS has not been fully elucidated. In the present study, we found that pre‐treatment with vitamin E analogs including αT (α‐tocopherol), αT3 (α ‐tocotrienol), γT, and γT3 for 24 h prevented the cultured cortical neurons from cell death in oxidative stress stimulated by H2O2, while Trolox, a cell‐permeable analog of αT, did not. The preventive effect of αT was dependent on de novo protein synthesis. Furthermore, we found that αT exposure induced the activation of both the MAP kinase (MAPK) and PI3 kinase (PI3K) pathways and that the αT‐dependent survival effect was blocked by the inhibitors, U0126 (an MAPK pathway inhibitor) or LY294002 (a PI3K pathway inhibitor). Interestingly, the up‐regulation of Bcl‐2 (survival promoting molecule) was induced by αT application. The up‐regulation of Bcl‐2 did not occur in the presence of U0126 or LY294002, suggesting that αT‐up‐regulated Bcl‐2 is mediated by these kinase pathways. These observations suggest that vitamin E analogs play an essential role in neuronal maintenance and survival in the CNS.
Test–retest reliability for two indices of ventilatory efficiency measured during cardiopulmonary exercise testing in healthy men and women
Authors: Davis James A. , Sorrentino Kristin M. , Ninness Erin M. , Pham Patrick H. , Dorado Silvia , Costello Kara B.
Published: April 2006

The level of ventilation (E) at a given carbon dioxide output (CO2) determines ventilatory efficiency. During cardiopulmonary exercise testing (CPET), ventilatory efficiency can be measured as the slope of the E versus CO2 relationship or the lowest /CO2. We evaluated the test–retest reliability of these two ventilatory efficiency indices in 29 healthy subjects (14 males). Each subject performed duplicate cycle ergometer tests on different days. Ventilation and the gas fractions for oxygen and CO2 were measured with a Vacumed metabolic cart. Linear regression analysis of the versus CO2 slope for the duplicate tests in the males, females, and both sexes combined yielded correlation coefficients of 0·822, 0·942, and 0·910, respectively. The corresponding correlation coefficients for the lowest /CO2 were 0·745, 0·929, and 0·884. A comparison of the test–retest correlation coefficients between the two ventilatory efficiency measures for the men, women, and both sexes combined revealed that they were not significantly different and, for a given index, there were no sex differences. The bias (mean of difference scores between tests) and 95% limits of agreement for the versus CO2 slope in the males, females, and both sexes combined were −0·05 ± 2·41, −0·57 ± 1·92, and −0·32 ± 2·20, respectively. The bias and 95% limits of agreement for the lowest /CO2 were very similar with values of 0·06 ± 2·45, −0·22 ± 2·03, and −0·10 ± 2·27. We conclude that the test–retest reliability for the versus CO2 slope and the lowest /CO2 is the same and that there is no sex difference in reliability for either index of ventilatory efficiency.
Use of a Pine Bark Extract and Antioxidant Vitamin Combination Product as Therapy for Migraine in Patients Refractory to Pharmacologic Medication
Authors: Chayasirisobhon Sirichai
Published: April 2006

Objective.—To evaluate the potential benefit of a pine bark extract and antioxidant vitamin combination product in the treatment of migraine headache.

Background.—This was an uncontrolled preliminary study to investigate the potential of an antioxidant formulation as therapy for migraine headache.

Methods.—Twelve patients with a long‐term history of migraine with and without aura who had failed to respond to multiple treatments with β‐blockers, antidepressants, anticonvulsants, and 5‐hydroxytryptamine receptor agonists were selected for the study. They were treated with 10 capsules of an antioxidant formulation of 120 mg pine bark extract, 60 mg vitamin C, and 30 IU vitamin E in each capsule daily for 3 months. Following enrollment patients completed a migraine disability assessment (MIDAS) questionnaire to give a baseline measure of migraine impact on work, school, domestic, and social activities over the previous 3 months. Patients were then treated for 3 months with the antioxidant formulation while continuing to receive existing pharmacologic medications. A second MIDAS was given at the conclusion of the treatment period.

Results.—There was a significant mean improvement in MIDAS score of 50.6% for the 3‐month treatment period compared with the 3 months prior to baseline (P < .005). The treatment was also associated with significant reductions in number of headache days and headache severity score. Mean number of headache days was reduced from 44.4 days at baseline (95% CI 28.9 to 59.8) to 26.0 days (95% CI 5.3 to 46.7; P < .005) after 3 months' therapy and mean headache severity was reduced from 7.5 of 10 (95% CI 6.7 to 8.4) to 5.5 (95% CI 4.1 to 7.0; P < .005).

Conclusion.—These data suggest that the antioxidant therapy used in this study may be beneficial in the treatment of migraine possibly reducing headache frequency and severity. Further clinical investigation into the efficacy of antioxidant as therapy for chronic migraine is warranted.
Kinetic deuterium isotope effects for 7‐alkoxycoumarin O‐dealkylation reactions catalyzed by human cytochromes P450 and in liver microsomes
Authors: Kim Keon‐Hee , Isin Emre M. , Yun Chul‐Ho , Kim Dong‐Hyun , Guengerich F.
Published: April 2006

7‐Ethoxy (OEt) coumarin has been used as a model substrate in many cytochrome P450 (P450) studies, including the use of kinetic isotope effects to probe facets of P450 kinetics. P450s 1A2 and 2E1 are known to be the major catalysts of 7‐OEt coumarin O‐deethylation in human liver microsomes. Human P450 1A2 also catalyzed 3‐hydroxylation of 7‐methoxy (OMe) coumarin at appreciable rates but P450 2E1 did not. Intramolecular kinetic isotope effects were used as estimates of the intrinsic kinetic deuterium isotope effects for both 7‐OMe and 7‐OEt coumarin dealkylation reactions. The apparent intrinsic isotope effect for P450 1A2 (9.4 for O‐demethylation, 6.1 for O‐deethylation) showed little attenuation in other competitive and noncompetitive experiments. With P450 2E1, the intrinsic isotope effect (9.6 for O‐demethylation, 6.1 for O‐deethylation) was attenuated in the noncompetitive intermolecular experiments. High noncompetitive intermolecular kinetic isotope effects were seen for 7‐OEt coumarin O‐deethylation in a baculovirus‐based microsomal system and five samples of human liver microsomes (7.3–8.1 for O‐deethylation), consistent with the view that P450 1A2 is the most efficient P450 catalyzing this reaction in human liver microsomes and indicating that the C‐H bond‐breaking step makes a major contribution to the rate of this P450 (1A2) reaction. Thus, the rate‐limiting step appears to be the chemistry of the breaking of this bond by the activated iron‐oxygen complex, as opposed to steps involved in the generation of the reactive complex. The conclusion about the rate‐limiting step applies to all of the systems studied with this model P450 1A2 reaction including human liver microsomes, the most physiologically relevant.
Zinc potentiates the antibacterial effects of histidine‐rich peptides against Enterococcus faecalis
Authors: Rydengård Victoria , Andersson Nordahl Emma , Schmidtchen Artur
Published: April 2006

Antimicrobial peptides are effector molecules of the innate immune system. We have recently shown that peptides containing multiples of the heparin‐binding Cardin and Weintraub motifs AKKARA and ARKKAAKA exert antimicrobial activities. Here, we show that replacement of lysine and arginine in these motifs by histidine abrogates the antibacterial effects of these peptides. Antibacterial activity of the histidine‐rich peptides against the Gram‐positive bacterium Enterococcus faecalis was restored by the addition of Zn2+. Fluorescence microscopy experiments showed that Zn2+ enabled binding of the histidine‐rich peptides to Enterococcus faecalis bacteria. Similar Zn2+‐dependent antibacterial activities were shown for histatin 5 as well as histidine‐containing peptides derived from the Zn2+‐ and heparin‐binding domain 5 of human kininogen. Thus, the results demonstrate a previously undisclosed Zn2+‐dependent antibacterial activity of kininogen‐derived peptides and indicate an important role for Zn2+ in regulating the antimicrobial activities of histidine‐rich peptides.
Inherited myopathy of great Danes
Authors: Feliu‐Pascual A. Lujan , Shelton G. D. , Targett M. P. , Long S. N. , Comerford E. J. , McMillan C. , Davies D. , Rusbridge C. , Mellor D. , Chang K. C. , Anderson T. J.
Published: April 2006

A hereditary, non‐inflammatory myopathy occurring in young great Danes with distinctive histological features in muscle biopsy specimens is reviewed. Onset of clinical signs is usually before one year of age and both sexes are affected. Clinical signs are characterised by exercise intolerance, muscle wasting, and an exercise‐induced tremor. Although most affected dogs have a severe form of the disease, occasional dogs may have a less pronounced form and survive into adulthood with an acceptable quality of life. Litters containing affected puppies are born to clinically unaffected parents, and an autosomal recessive pattern of inheritance is likely. All recorded cases have had fawn or brindle coat coloration. Elevated serum creatinine kinase concentrations and spontaneous electrical activity in skeletal muscles are frequently found. While originally reported (Targett and others 1994) as a central core myopathy in this breed, the histochemical characteristics of the distinct cytoarchitectural structures differ from those of the well‐characterised central core myopathy in human beings. In fact, these structures differ from any known myopathy in human beings and likely represents a unique non‐inflammatory myopathy affecting dogs. Until this myopathy is characterised further, the name inherited myopathy in great Danes is suggested.
POPULATION SIZE, DISTRIBUTION, AND BEHAVIOR OF INDO‐PACIFIC BOTTLENOSE (TURSIOPS ADUNCUS) AND HUMPBACK (SOUSA CHINENSIS) DOLPHINS OFF THE SOUTH COAST OF ZANZIBAR
Authors: Stensland Eva , Carlén Ida , Särnblad Anna , Bignert Anders , Berggren Per
Published: April 2006

Abstract

Indo‐Pacific bottlenose (Tursiops aduncus) and humpback dolphins (Sousa chinensis) off the south coast of Zanzibar, East Africa, have been subject to both direct and indirect takes as well as disturbance from local dolphin tourism during the last decade. Meanwhile, little or no information on population parameters exists for these animals. In order to assess the anthropogenic threats, a study was conducted between 1999 and 2002 to determine population sizes, distribution, and behavior of these animals. Population sizes were calculated for each year using mark‐recapture methods applied to photo‐identification data. The estimates ranged between 136 and 179 for the bottlenose dolphins and between 58 and 65 for the humpback dolphins in the calculated 26 km2 study area. Patterns in distribution and behavior were investigated using image and spatial statistic software on data from boat surveys. Analyses of spatial densities showed that both species concentrated their activities to smaller areas (2%–11.5%) within the study area. When the study results were considered in light of the anthropogenic threats, it was clear that immediate conservation measures were needed. This is critical if the negative impact on the species is to be minimized and the dolphins are to continue to represent a socioeconomic resource in the region.
Heat Conduction in Nanofluid Suspensions
Authors: Vadasz Peter
Published: April 2006

The heat conduction mechanism in nanofluid suspensions is derived for transient processes attempting to explain experimental results, which reveal an impressive heat transfer enhancement. In particular, the effect of the surface-area-to-volume ratio (specific area) of the suspended nanoparticles on the heat transfer mechanism is explicitly accounted for, and reveals its contribution to the specific solution and results. The present analysis might provide an explanation that settles an apparent conflict between the recent experimental results in nanofluid suspensions and classical theories for estimating the effective thermal conductivity of suspensions that go back more than one century (Maxwell, J.C., 1891, Treatise on Electricity and Magnetism). Nevertheless, other possible explanations have to be accounted for and investigated in more detail prior to reaching a final conclusion on the former explanation.
Study of Infrared CO2 Radiation From Liquid-Fueled Combustor
Authors: Levy Y. , Lev M. , Ovcharenko V.
Published: April 2006

The combustor that is a 30% flat (rectangular) model of an annular turbojet-engine combustion chamber was studied. It gave a turbulent nonpremixed kerosene-air flame with equivalence ratios within the range of 0.15–0.75. Measurements of CO2 infrared radiation were performed on exhaust gases from a combustor. The infrared radiation images were obtained by an IR camera equipped with a narrow bandpass filter that falls on the CO2 fundamental band. Temperature profiles were measured by the thermocouple at the combustor outlet. The in-house program INFRAD was used to calculate infrared radiation from the CO2 component of the efflux gases from the combustor. The calculation was performed, taking into account the effects of radiation emission and absorption along an optical path. The calculations that allow prediction of “apparent” gas temperatures are those expected to be read by the IR camera. The calculated results are compared with experimental measurements. They are found to be in close agreement.
Numerical and Experimental Investigation of Thermal Signatures of Buried Landmines in Dry Soil
Authors: Moukalled F. , Ghaddar N. , Kabbani H. , Khalid N. , Fawaz Z.
Published: April 2006

This paper reports a numerical and experimental investigation conducted to study the thermal signature of buried landmines on soil surface. A finite-volume-based numerical model was developed to solve the unsteady three-dimensional heat transport equation in dry homogeneous soil with a buried mine. Numerical predictions of soil thermal response were validated by comparison with published analytical and numerical values in addition to data obtained experimentally. Experiments were performed inside an environmental chamber and soil temperatures were measured during cooling, using two measurement techniques, after exposing the soil surface to a radiant heat flux for a specified period. In the first technique, the temporal variation of the surface and internal soil temperatures were recorded using thermocouples. In the second technique, the soil surface temperature was measured using an infrared camera that revealed the thermal signature of the mine. The transient temperature profiles generated numerically agreed with measurements, and the difference between predicted and measured values was less than 0.3°C at both the soil surface and in depth. The accurate matching of numerical and IR images at the surfaces was found to strongly depend on the use of a smaller soil thermal conductivity at the surface than at greater depths. The numerical model was used to predict the dependence of the peak thermal contrast on time, depth, and heating period. The thermographic analysis, when combined with numerical predictions, holds promise as a method for detecting shallowly buried land mines.
Performance Evaluation of Photovoltaic Power-Generation System Equipped With a Cooling Device Utilizing Siphonage
Authors: Furushima Kaoru , Nawata Yutaka
Published: April 2006

In order to construct an efficient photovoltaic (PV) power-generation system, we have developed a new system equipped with a cooling device utilizing siphonage. The major components of the system are an array of PV modules and cooling panels attached to the backside of the PV modules. The PV modules are cooled with cooling water flowing through a narrow gap in each cooling panel, and hot water discharged from the cooling panel can be reused. In order to save energy for introducing cooling water into the panel, siphonage from an upper level of a building to the ground level is utilized. From long-term monitoring tests in summer for the PV system, we confirmed that the cooling of the PV modules increases the electric power and that the reuse of hot water from the cooling panel contributes very much for saving energy consumed in a hot-water-supply system.
Assessment of Renewable Energy Solutions in an Italian Small Island Energy System Using a Transient Simulation Model
Authors: Corsini Alessandro , Gamberale Mario , Rispoli Franco
Published: April 2006

This paper presents a transient model of the energy system of the small Italian island of Ventotene. The model has been developed as a tool to validate the performance related to the integration of renewable energy technologies and energy efficiency measures into the island stand-alone power system, in presence of seasonal-dependent electric load equilibrium conditions. A hydrogen-based energy system has been proposed as an effective option for the seasonal buffering of the stochastic power contribution from renewable energy sources. The time-dependent behavior of the hybrid, diesel, and hydrogen-renewable, power generation system has been investigated by matching it with the electric load data with an hourly distribution over the period of one reference year. The technical feasibility and the behavior of the systems have been evaluated in terms of its electric and environmental performance.