bluuebunny/crossref_metadata_2025 huggingface dataset:
Ascorbate Enhances Photogeneration of Hydrogen Peroxide Mediated by the Iris Melanin†
Authors: Wielgus Albert R. , Sarna Tadeusz
Published: April 2008

The iris in the human eye is exposed to UV and visible light transmitted by the cornea. This pigmented tissue is bathed with the aqueous humor (AqH), which contains high concentration of ascorbate. It has been postulated that the presence of ascorbate in AqH can contribute to increased photoproduction of H2O2 mediated by the iris melanin. In this study, we monitored generation of H2O2 induced by UV–VIS irradiation of bovine irides, bovine and human iris homogenates and iris melanin. Our data show that exogenous ascorbate significantly amplified the rate of H2O2 photoformation in all melanotic samples. Deactivation of endogenous catalase with NaN3 in bovine irides increased the level of the accumulated H2O2 in the bathing solution following sample irradiation. Photoformation of H2O2 in samples with exogenous ascorbate was accompanied by its photo‐oxidation. Both photoprocesses exhibited significant wavelength dependence. EPR spectroscopy measurements showed that ascorbyl radical is an intermediate product of the ascorbate photo‐oxidation. The photoproduction of H2O2 and photo‐oxidation of ascorbate appear to be stoichiometric processes. No significant differences in the photoreactivity of iridial melanin from donors of different age and iris color was found. We postulate that also in vivo ascorbate increases the rate of iris melanin‐mediated photoformation of H2O2 and its steady state concentration in AqH.
Comparable Photoreactivity of Hair Melanosomes, Eu‐ and Pheomelanins at Low Concentrations: Low Melanin a Risk Factor for UVA Damage and Melanoma?†
Authors: Haywood Rachel M. , Lee Martin , Andrady Carima
Published: April 2008

Melanin is known to be photoreactive and photoprotective, but its function in skin in vivo is still debated. Data is lacking of the effects of UVA irradiation on human skin melanosomes of different pigmentation, which have not been extensively degraded by isolation procedures. We have shown previously that melanosomes isolated from human oriental and black cat hair, and synthetic eumelanins, are photoreactive producing superoxide at low concentrations when exposed to UVA irradiation comparable to UK levels of sunlight. Here we investigated the UVA‐irradiation of melanosomes, isolated from different colored human hair samples, using electron spin resonance spectroscopy and spin trapping. Comparable irradiation of synthetic pheomelanins synthesized from l‐dopa and l‐cysteine was also studied. An alkali method (5 min NaOH at 90°C) could be used to isolate oriental hair melanosomes but was not suitable for auburn and blonde hair. Dithiothreitol and proteinase K resulted in melanin release from possible over‐digestion of melanosomes; however, dithiothreitol and papain resulted in no melanin release and good melanosome yields with separation from residual keratin for brown, auburn and blonde hair. Melanosomes isolated by the latter method and synthetic pheomelanins were similar in UVA‐photoreactivity at low concentrations, independent of hair color, and broadly comparable to synthetic melanins. Melanosome concentration at constant fluence may be more significant with respect to photodamage and UVA photocarcinogenesis (melanoma) via superoxide radical production than pigment type.
Increased exhaled nitrite in children with allergic asthma is not related to nitric oxide formation
Authors: Zetterquist Wilhelm , Marteus Helena , Hedlin Gunilla , Alving Kjell
Published: April 2008

Introduction:  Nitrite sampled from the upper airways could originate from inflammation‐induced nitric oxide (NO), as reports of elevated nitrite in exhaled breath condensate (EBC) from asthmatics suggest, but also through bacterial action in the pharyngo‐oral tract.

Objectives:  To correlate EBC nitrite and nitrate to exhaled NO (FENO, fraction of expired NO) and other markers of disease activity in children with allergic asthma and thereby further investigate their role and origin.

Materials and methods: EBC was collected from 27 asthmatic subjects (ages 6–17 years, all immunoglobulin E‐positive for aeroallergens) and 21 age‐matched non‐atopic healthy controls for fluorometric analysis of nitrite and nitrate. These markers were compared with measurements of FENO, blood eosinophil count (EOS), methacholine reactivity (PD20) and baseline spirometry.

Results:  EBC nitrite, in contrast to nitrate, was significantly increased (P < 0.01) in the asthmatic children. They also had increased levels of FENO (P < 0.001) and EOS (P < 0.001) along with decreased PD20 (P < 0.001) and FEV1/FVC (P < 0.01). However, there was no correlation between EBC nitrite and FENO (r = 0.05) or any other marker of disease activity in the asthmatic children, whereas between the other markers correlations could be established.

Conclusion:  EBC nitrite is elevated in childhood asthma but the lack of correlation to FENO and other markers, together with simultaneously normal levels of nitrate, make its origin as a metabolite of inflammation‐induced NO questionable.

Please cite this paper as: Zetterquist W, Marteus H, Hedlin G and Alving G. Increased exhaled nitrite in children with allergic asthma is not related to nitric oxide formation. The Clinical Respiratory Journal 2008; 2: 166–174.
An unusual cause of diffuse pulmonary haemorrhage
Authors: Hui Cathryn
Published: April 2008

Introduction:  Diffuse pulmonary haemorrhage is a potentially life‐threatening complication of a variety of conditions. Tumours, including angiosarcoma lung metastases, are an unusual cause of pulmonary haemorrhage.

Methods:  Report of a case.

Results:  This case describes a 38‐year‐old previously healthy male who presented with chest wall bruising followed by haemoptysis and a cerebellar haemorrhage. The patient developed diffuse pulmonary haemorrhage. A biopsy of the chest wall lesion indicated a haematoma and an open‐lung biopsy suggested the diagnosis of vasculitis. The patient died within 3 months after initial presentation and an autopsy revealed a chest wall angiosarcoma with pulmonary and cerebellar metastases.

Conclusion:  Pulmonary angiosarcoma metastases should be included in the differential diagnosis of diffuse pulmonary haemorrhage, especially in a young, previously healthy patient with normal renal function, particularly as the pathological diagnosis may be difficult and even misleading.

Please cite this paper as: Hui C. An unusual cause of diffuse pulmonary haemorrhage. The Clinical Respiratory Journal 2008; 2: 183–186.
Dental findings in Kabuki make‐up syndrome: a case report
Authors: Rocha Cristiane Tomaz , Peixoto Iza Teixeira Alves , Fernandes Patrícia Motta , Torres Carolina Paes , De Queiroz Alexandra Mussolino
Published: April 2008

This article documents the case history of a 9‐year‐old Brazilian child diagnosed with Kabuki make‐up syndrome (KMS). The clinical features are described, with emphasis on the craniofacial and orodental manifestations. The patient had the distinctive KMS craniofacial features consisting of long palpebral fissure, hypertelorism, high‐arched eyebrows with sparse hair in the lateral one‐third, eyes with eversion of the lateral one‐third of the lower eyelids, long and curved eyelashes, palpebral ptosis, large anteverted prominent ears in a lower position, broad, depressed nasal root with a flat nasal tip, and mild neuropsychomotor developmental deficits. The intraoral examination revealed an anterior open bite, overretention of primary teeth, and a high‐arched palate. Two findings in this child have not been previously reported in patients with KMS: the presence of supernumerary teeth and taurodontic teeth in the maxillary arch. The clinical and radiographic detection of these unique dental features may be helpful in identifying children who may have milder forms of KMS.
Prevalence of dental trauma in patients with cerebral palsy
Authors: De Moraes Costa Mariana Machado Teixeira , Afonso Rebeca Lima , Ruviére Denise Belucio , Aguiar Sandra Maria Herondina Coelho Ávila
Published: April 2008

This study presents the findings of a record review that evaluated the prevalence of dental trauma in patients with cerebral palsy and evaluated its possible relationship with age, type of palsy, and epilepsy. The dental records of 2,200 patients with special needs admitted to the special care clinic of the School of Dentistry of Araçatuba/UNESP, Brazil, between 1998 and 2003 were reviewed. Of the records that were analyzed, 500 patients who had cerebral palsy were selected for this study. Information regarding age, gender, type of palsy and dental trauma was collected and statistically analyzed.

It was observed that 10.6% of the subjects (n = 53) had sustained dental trauma. The number of traumatized teeth was 84. Enamel or enamel/dentin fractures were the most frequent types of traumatic injury (84.9%). The permanent maxillary central incisors were the most commonly affected teeth (50%). The frequency of traumatic injuries showed no significant correlation (p> .05) with the type of cerebral palsy or gender and they were more frequent in subjects between the ages of 0 and 12 years. Having epilepsy was not a statistically significant risk factor (p> .05) for dental trauma.
Oral health, dental treatment, and cardiac valve surgery outcomes
Authors: Wu Grace Hsiao , Manzon Steve , Badovinac Rachel , Woo Sook‐Bin
Published: April 2008

The aim of this study was to determine whether not treating chronic dental infection during the admission for cardiac valve surgery would increase the morbidity and mortality of patients.

Patients were divided into three groups: dentally unhealthy and untreated (Group A), dentally healthy not requiring treatment (Group B), and dentally unhealthy and treated (Group C). Hospital computer records and phone interviews were used to assess morbidity and mortality as assessed through the Social Security Death Index.

Ninety‐eight patient charts were reviewed. Patients in Group A (n = 47)were not at a significantly greater risk for developing infective endocarditis (IE) within 6 months of cardiac surgery compared to patients in Groups B (n = 17) and C (n = 34). Also, patients in Group A did not have a significantly higher rate of mortality compared to other groups (p= .09).

The results suggest that there is no need to treat chronic oral infections in patients with compromised cardiac function within 24 to 48 hours prior to cardiac valve replacement surgery since this will not lower the risk of IE and death following cardiac valve surgery. Multicenter prospective case‐controlled studies are needed to address this question definitively.
Doxepin rinse for management of mucositis pain in patients with cancer: one week follow‐up of topical therapy
Authors: Epstein Joel B. , Epstein Joshua D. , Epstein Matthew S. , Oien Hal , Truelove Edmond L.
Published: April 2008

This study assessed the effectiveness of oral doxepin rinse for mucositis‐related pain management in patients following 1 week of repeated dosing. Patients with oral mucositis due to head and neck radiation therapy or hematopoietic stem cell transplant (HSCT) were recruited to participate in a 1‐week follow‐up study. Subjects who gave informed consent rinsed with doxepin (5 ml) during the initial visit and were then told to use doxepin rinse over the next week as needed, three to six times per day, and return for a follow‐up visit. At each visit, mucositis was scored using the Oral Mucositis Assessment Scale and oral pain was assessed using a visual analogue scale before and after rinsing. The use of a systemic analgesic was recorded, and side effects were documented. At the follow‐up visit, subjects were also asked to retrospectively report average pain scores they experienced over the past week, 5 and 15 minutes following rinse. Nine subjects were enrolled in the study. Statistically significant reductions in pain scores were reported for 2 hours following doxepin rinse during the initial visit (p < .05). Patients recalled that their pain significantly dropped within 5 minutes of rinsing over the week of repeated dosing (p < .05). At the follow‐up visit, subjects reported statistically significant pain reduction 5 minutes after doxepin rinsing (p < .05).

These results indicate that doxepin rinsing continues to produce reduced intensity of pain levels over a 1‐week span of repeated dosing.
Juvenile Dogs as Potential Sentinels for West Nile Virus Surveillance
Authors: Resnick M. P. , Grunenwald P. , Blackmar D. , Hailey C. , Bueno R. , Murray K. O.
Published: April 2008

We conducted a study to determine whether juvenile stray dogs could be sentinels for West Nile virus (WNV) surveillance. Seroconversion was detected 6 weeks before the first reported human case. Our findings provide evidence that dogs could be useful sentinels for monitoring areas for evidence of WNV during transmission seasons.
Frequencies of PRNP Gene Polymorphisms in Vietnamese Dairy Cattle for Potential Association with BSE
Authors: Muramatsu Y. , Sakemi Y. , Horiuchi M. , Ogawa T. , Suzuki K. , Kanameda M. , Hanh T. T. , Tamura Y.
Published: April 2008

Since 2004, significant associations between bovine spongiform encephalopathy (BSE) susceptibility in cattle and frequencies of insertion/deletion (ins/del; indel) polymorphisms within the bovine prion protein gene (PRNP) have been reported. In this study, we investigated the frequencies of indel polymorphisms within two variable sites, a 23‐bp indel polymorphism in the promoter region (23indel) and a 12‐bp indel polymorphism in intron 1 region (12indel), in the PRNP in 206 Vietnamese dairy cattle and seven Japanese BSE‐affected cattle. In Vietnamese dairy cattle, the frequency distributions of del allele and del/del genotypic polymorphisms in the 23indel site, which are thought to be associated with BSE susceptibility, were significantly higher, whereas the frequencies of del allelic and del/del genotypic polymorphisms in the 12indel site, which have been reported to confer BSE susceptibility, were significantly lower. We have provided evidence that Vietnamese dairy cattle have a unique genetic background in the PRNP gene in comparison with cattle or sires previously reported in other countries.
All Creatures Great and Minute: A Public Policy Primer for Companion Animal Zoonoses
Authors: Reaser J. K. , Clark E. E. , Meyers N. M.
Published: April 2008

Approximately 63% of US households have at least one pet, a large percentage of which are considered family members. Pet owners can derive substantial physical and psychological benefits from interaction with companion animals. However, pet ownership is not without risks; zoonotic diseases are increasingly drawing the attention of healthcare professionals, policy makers and the general public. While zoonoses of ‘traditional’ pets are widely recognized and their prevention and treatment factors are generally known, the growing popularity of ‘non‐traditional’ pets has the potential to facilitate human exposure to novel zoonoses. However, the greatest risk of zoonoses probably arises from animals taken directly from the wild to serve as pets. Non‐governmental organizations, state veterinary associations and others have been calling for increased regulation of animal imports, some proposing that all ‘exotics’ be banned from the pet trade. Because zoonotic diseases of companion animals are influenced by interacting factors of ecological, technical, socio‐economic, and political origin, efforts to minimize their impact need be multi‐dimensional, simultaneously addressing both the ecological and socio‐political drivers of disease emergence and transmission. This study is intended to serve as a primer for animal care professionals seeking to engage with policy makers and the pet industry on the prevention of companion animal zoonoses. We provide background on the human–animal bond, risks of zoonoses associated with groups of companion animals, and the public policy context, as well as identify the factors needed to build a comprehensive approach to companion animal zoonoses risk management. Also included are examples of innovative, non‐regulatory initiatives designed to limit the spread and impact of companion animal zoonoses, including a reptile salmonella poster, theNational Reptile Improvement Plan, HabitattitudeTMcampaign, Pet Zoonoses Committee, and a wildlife disease surveillance initiative known as Project TripWire.
Effect of Boiling Water Carcass Immersion on Aerobic Bacteria Counts of Poultry Skin and Processed Ground Poultry Meat
Authors: Tompkins N. M. , Avens J. S. , Kendall P. A. , Salman M. D.
Published: April 2008

This study was conducted to determine the relationship between bacteria destruction on poultry carcass skin and bacteria in raw ground poultry meat from the same carcasses. Immersion time in boiling water of broiler chicken whole carcasses required for maximum reduction of naturally occurring aerobic bacterial count on skin was measured. Treatments for chicken carcasses consisted of immersion in boiling water (∼95°C) for 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, and 4 min. Four skin samples taken following treatment and three taken from subsequently ground carcass meat were analyzed for total aerobic plate counts (APC). Analysis of the data indicated a linear increase in bacterial destruction on skin with increased boiling water immersion time from 0 to 4 min. Reduction of skin bacteria to less than 1 log10 occurred at 3 min carcass immersion or longer. The analysis also indicated that treatment with boiling water and removal of skin was effective in reducing bacterial counts in ground meat to similar levels at all treatment times from 0.5 to 4.0 min. Findings from this study indicated that a boiling water immersion intervention and removal of skin could reduce subsequent bacteria contamination of ground meat. This intervention could minimize the risk of pathogen‐contaminated primary processed poultry carcasses used in further processing.
Antibody Response to an Anti‐rabies Vaccine in a Dog Population under Field Conditions in Bolivia
Authors: Suzuki K. , González E. T. , Ascarrunz G. , Loza A. , Pérez M. , Ruiz G. , Rojas L. , Mancilla K. , Pereira J. A. C. , Guzman J. A. , Pecoraro M. R.
Published: April 2008

Rabies remains an important public health issue in Bolivia, South America. Public concern and fears are most focussed on dogs as the source of rabies. The objective of the present study was to assess immunity of an inactivated suckling mouse brain vaccine against canine rabies used for the official vaccination campaigns under field conditions in an endemic area of rabies in Bolivia. A total of 236 vaccinated and 44 unvaccinated dogs in Santa Cruz de la Sierra, selected using stratified random sampling, were investigated in order to obtain owned dog characteristics and antibody titres against rabies in April 2007. The proportion of vaccinated dogs with an antibody titre exceeded the protection threshold value of 0.5 EU/ml was 58% [95% confidence intervals (CI): 52–65], indicating that vaccination is likely to elicit an antibody response (odds ratio 6.3, 95% CI: 1.2–11.5). The range of geometric mean of antibody titre for vaccinated dogs (0.89 EU/ml; 95% CI: 0.75–1.04) was considered to meet the minimal acceptable level indicating an adequate immune response to the vaccine. However, the titre level was not satisfactory in comparison with the results from other field investigations with inactivated tissue culture vaccines. It is recommended for public health authorities to (1) consider modernizing their vaccine manufacturing method because the level of immunity induced by the current vaccine is comparably low, (2) conduct frequent vaccination campaigns to maintain high levels of vaccination coverage, and (3) actively manage the domestic dog population in the study area, which is largely responsible for rabies maintenance.
The Probiotic
Lactobacillus johnsonii
NCC 533 Produces High-Molecular-Mass Inulin from Sucrose by Using an Inulosucrase Enzyme
Authors: Anwar Munir A. , Kralj Slavko , van der Maarel Marc J. E. C. , Dijkhuizen Lubbert
Published: April 2008

Fructansucrase enzymes polymerize the fructose moiety of sucrose into levan or inulin fructans, with β(2-6) and β(2-1) linkages, respectively. The probiotic bacterium
Lactobacillus johnsonii
strain NCC 533 possesses a single fructansucrase gene (open reading frame AAS08734) annotated as a putative levansucrase precursor. However,
13
C nuclear magnetic resonance (NMR) analysis of the fructan product synthesized in situ revealed that this is of the inulin type. The
ftf
gene of
L. johnsonii
was cloned and expressed to elucidate its exact identity. The purified
L. johnsonii
protein was characterized as an inulosucrase enzyme, producing inulin from sucrose, as identified by
13
C NMR analysis. Thin-layer chromatographic analysis of the reaction products showed that InuJ synthesized, besides the inulin polymer, a broad range of fructose oligosaccharides. Maximum InuJ enzyme activity was observed in a pH range of 4.5 to 7.0, decreasing sharply at pH 7.5. InuJ exhibited the highest enzyme activity at 55°C, with a drastic decrease at 60°C. Calcium ions were found to have an important effect on enzyme activity and stability. Kinetic analysis showed that the transfructosylation reaction of the InuJ enzyme does not obey Michaelis-Menten kinetics. The non-Michaelian behavior of InuJ may be attributed to the oligosaccharides that were initially formed in the reaction and which may act as better acceptors than the growing polymer chain. This is only the second example of the isolation and characterization of an inulosucrase enzyme and its inulin (oligosaccharide) product from a
Lactobacillus
strain. Furthermore, this is the first
Lactobacillus
strain shown to produce inulin polymer in situ.
Development and Use of an Efficient System for Random
mariner
Transposon Mutagenesis To Identify Novel Genetic Determinants of Biofilm Formation in the Core
Enterococcus faecalis
Genome
Authors: Kristich Christopher J. , Nguyen Vy T. , Le Thinh , Barnes Aaron M. T. , Grindle Suzanne , Dunny Gary M.
Published: April 2008

Enterococcus faecalis
is a gram-positive commensal bacterium of the gastrointestinal tract and an important opportunistic pathogen. Despite the increasing clinical significance of the enterococci, most of the genetic analysis of these organisms has focused on mobile genetic elements, and existing tools for manipulation and analysis of the core
E. faecalis
chromosome are limited. We are interested in a comprehensive analysis of the genetic determinants for biofilm formation encoded within the core
E. faecalis
genome. To identify such determinants, we developed a substantially improved system for transposon mutagenesis in
E. faecalis
based on a mini-
mariner
transposable element. Mutagenesis of wild-type
E. faecalis
with this element yielded predominantly mutants carrying a single copy of the transposable element, and insertions were distributed around the entire chromosome in an apparently random fashion. We constructed a library of
E. faecalis
transposon insertion mutants and screened this library to identify mutants exhibiting a defect in biofilm formation. Biofilm-defective mutants were found to carry transposon insertions both in genes that were previously known to play a role in biofilm formation and in new genes lacking any known function; for several genes identified in the screen, complementation analysis confirmed a direct role in biofilm formation. These results provide significant new information about the genetics of enterococcal biofilm formation and demonstrate the general utility of our transposon system for functional genomic analysis of
E. faecalis
.
New Aspects of Neotropical Polycystic (
Echinococcus vogeli
) and Unicystic (
Echinococcus oligarthrus
) Echinococcosis
Authors: D'Alessandro Antonio , Rausch Robert L.
Published: April 2008

Of the four species of the genus
Echinococcus
(Cestoda) distinguished by biological and morphological characteristics, two species,
E. vogeli
and
E. oligarthrus
, occur widely in the Neotropics. Approximately 200 cases of polycystic echinococcosis (PE) have been recorded from 12 countries in South America. Following early proliferation of
E. vogeli
in the human host, typically in the liver, the metacestode usually spreads in the peritoneal and pleural cavities, and numerous organs may be invaded. The clinical characteristics of PE in 81 patients with sufficient information are reviewed. Type I disease consists of polycysts in the liver and abdominal cavity (37% of the patients had this characteristic); type II is similar to type I but also includes hepatic insufficiency (26%); type III consists of cysts in liver and chest (14%); type IV consists of cysts only in the mesenteries (16%); and type V consists of cysts calcified in liver and lung (4%). The percentage of patients with polycysts in the liver was 81%, and the percentage of patients with polycysts in the chest was 14%. PE is most ready diagnosed by geographic origin of the patient and by means of ultrasound or computerized tomography scanning showing cysts and calcifications. The highest mortality was for patients with type II disease, due to hepatic failure and its complications. There were five patients who died due to surgical accidents, whereas 35 cases had uncomplicated surgery. Twenty-three patients died of PE, making the total mortality 29% (23 of 78 cases). None of the 13 patients treated only with albendazole, the most efficacious treatment, was completely cured. PE represents a severe medical problem in South America. A reevaluation of the characteristics of the metacestode of
E. oligarthrus
indicated that it is unicystic. Only three human cases are known (two with infection in the orbit and one with infection in the heart). The metacestode of
E. oligarthrus
, in contrast with that of
E. vogeli
, consists of a spherical, fluid-filled vesicle that enlarges concentrically and is not known to undergo exogenous proliferation.
Cavitary Pulmonary Disease
Authors: Gadkowski L. Beth , Stout Jason E.
Published: April 2008

A pulmonary cavity is a gas-filled area of the lung in the center of a nodule or area of consolidation and may be clinically observed by use of plain chest radiography or computed tomography. Cavities are present in a wide variety of infectious and noninfectious processes. This review discusses the differential diagnosis of pathological processes associated with lung cavities, focusing on infections associated with lung cavities. The goal is to provide the clinician and clinical microbiologist with an overview of the diseases most commonly associated with lung cavities, with attention to the epidemiology and clinical characteristics of the host.
The Relationship between Leishmaniasis and AIDS: the Second 10 Years
Authors: Alvar Jorge , Aparicio Pilar , Aseffa Abraham , Den Boer Margriet , Cañavate Carmen , Dedet Jean-Pierre , Gradoni Luigi , Ter Horst Rachel , López-Vélez Rogelio , Moreno Javier
Published: April 2008

To date, most Leishmania and human immunodeficiency virus (HIV) coinfection cases reported to WHO come from Southern Europe. Up to the year 2001, nearly 2,000 cases of coinfection were identified, of which 90% were from Spain, Italy, France, and Portugal. However, these figures are misleading because they do not account for the large proportion of cases in many African and Asian countries that are missed due to a lack of diagnostic facilities and poor reporting systems. Most cases of coinfection in the Americas are reported in Brazil, where the incidence of leishmaniasis has spread in recent years due to overlap with major areas of HIV transmission. In some areas of Africa, the number of coinfection cases has increased dramatically due to social phenomena such as mass migration and wars. In northwest Ethiopia, up to 30% of all visceral leishmaniasis patients are also infected with HIV. In Asia, coinfections are increasingly being reported in India, which also has the highest global burden of leishmaniasis and a high rate of resistance to antimonial drugs. Based on the previous experience of 20 years of coinfection in Europe, this review focuses on the management of Leishmania-HIV-coinfected patients in low-income countries where leishmaniasis is endemic.
Identification of Mating Type Genes in the Bipolar Basidiomycetous Yeast
Rhodosporidium toruloides
: First Insight into the
MAT
Locus Structure of the
Sporidiobolales
Authors: Coelho Marco A. , Rosa André , Rodrigues Nádia , Fonseca Álvaro , Gonçalves Paula
Published: April 2008

Rhodosporidium toruloides
is a heterothallic, bipolar, red yeast that belongs to the
Sporidiobolales
, an order within a major lineage of basidiomycetes, the
Pucciniomycotina
. In contrast to other basidiomycetes, considerably less is known about the nature of the mating type (
MAT
) loci that control sexual reproduction in this lineage. Three genes (
RHA1, RHA2
, and
RHA3
) encoding precursors of the
MAT A1
pheromone (rhodotorucine
A
) were previously identified and formed the basis for a genome walking approach that led to the identification of additional
MAT
genes in complementary mating strains of
R. toruloides
. Two mating type-specific alleles encoding a p21-activated kinase (PAK; Ste20 homolog) were found between the
RHA2
and
RHA3
genes, and identification in
MAT A2
strains of a gene encoding a presumptive pheromone precursor enabled prediction of the structure of rhodotorucine
a
. In addition, a putative pheromone receptor gene (
STE3
homolog) was identified upstream of
RHA1
. Analyses of genomic data from two closely related species,
Sporobolomyces roseus
and
Sporidiobolus salmonicolor
, identified syntenic regions that contain homologs of all the above-mentioned genes. Notably, six novel pheromone precursor genes were uncovered, which encoded, similarly to the
RHA
genes, multiple tandem copies of the peptide moiety. This suggests that this structure, which is unique among fungal lipopeptide pheromones, seems to be prevalent in red yeasts. Species comparisons provided evidence for a large, multigenic
MAT
locus structure in the
Sporidiobolales
, but no putative homeodomain transcription factor genes (which are present in all basidiomycetous
MAT
loci characterized thus far) could be found in any of the three species in the vicinity of the
MAT
genes identified.
Gait-related intrinsic risk factors for patellofemoral pain in novice recreational runners
Authors: Thijs Y , De Clercq D , Roosen P , Witvrouw E
Published: April 2008

Objective:

To determine prospectively gait-related intrinsic risk factors for patellofemoral pain (PFP) in a population of novice recreational runners.

Design:

Prospective cohort study.

Participants:

102 novice recreational runners (89 women) with no history of knee or lower leg complaints.

Interventions:

The standing foot posture of the subjects was examined and plantar pressure measurements during running were collected. The subjects then participated in a 10-week “start to run” programme. During this period all sports injuries were registered by a sports medicine physician.

Main outcome measurements:

The relationship between the standing foot posture and PFP was investigated and gait-related intrinsic risk factors for PFP were determined.

Results:

The 17 runners who developed PFP exerted a significantly higher vertical peak force underneath the lateral heel and metatarsals 2 and 3. Logistic regression analysis showed that a significantly higher vertical peak force underneath the second metatarsal and shorter time to the vertical peak force underneath the lateral heel were predictors for PFP. No significant evidence was found for an association between an excessively pronated or supinated foot posture and the development of PFP.

Conclusions:

The findings suggest that an excessive impact shock during heel strike and at the propulsion phase of running may contribute to an increased risk of developing PFP. The hypothesis that persons at risk for PFP show an altered static foot posture in comparison with non-afflicted persons is not supported by the results of this study.
The biological roles of exercise-induced cytokines: IL-6, IL-8, and IL-15
Authors: Nielsen Anders Rinnov , Pedersen Bente Klarlund
Published: April 2008

Skeletal muscle fibers express several cytokines, including interleukin (IL)-6, IL-8, and IL-15. Solid evidence exists that muscular IL-6 and IL-8 are regulated by muscle contractions, at both the mRNA and the protein levels. IL-6 increases insulin-stimulated glucose disposal and fatty acid oxidation in humans in vivo. Both IL-6 and IL-8 are released from working skeletal muscle, but because IL-6 contributes to the systemic circulation only a small transient net release of IL-8 is found from working muscle, suggesting that IL-8 may exert its effects locally in the muscle. IL-15 is a recently discovered growth factor, which is highly expressed in skeletal muscle. Interestingly, although IL-15 has been demonstrated as having anabolic effects on skeletal muscle in vitro and in vivo, it seems to play a role in reducing adipose tissue mass, and a role for IL-15 in muscle–fat cross-talk has been hypothesized. In conclusion, muscle-derived cytokines appear to have important roles in metabolism, and exercise plays a role in orchestrating the interplay between cytokines and metabolism.
Changes in interstitial K+ and pH during exercise: implications for blood flow regulation
Authors: Juel Carsten
Published: April 2008

The analysis of blood samples has clearly demonstrated that exercise is associated with the release of K+ and H+ from muscle. However, blood samples give only incomplete information about the ion changes in the muscle interstitium. Interstitial changes in ion composition may affect the transport properties of the sarcolemmal membrane, may affect fibre excitability and induce fatigue, and may affect sensory nerve endings. Therefore, to better understand muscle function, it is important to quantify the exercise-induced interstitial ion changes. Both interstitial K+ and H+ changes have been quantified with the microdialysis technique. Interstitial K+ accumulation is dependent on the intensity and duration of muscle activity and may reach 10 mmol/L during intense exercise, and the concentration in T-tubules may be even higher. Thus, interstitial K+ can reach a level that affects fibre excitability and the development of fatigue. It has also been demonstrated with microdialysis that the interstitial decrease in pH during muscle activity is larger than the reduction in blood pH. Ion changes in the interstitium may affect blood flow directly or indirectly. Infusion of K+ into the femoral artery in humans has demonstrated that blood flow is affected by changes in K+ as low as 0.1 mmol/L. The vasodilatory effect of K+ can be inhibited with simultaneous barium infusion, indicating that inward rectifier potassium (Kir)channels are involved. Acidosis has a direct effect on blood flow and an indirect effect, mediated by changes in other vasoactive compounds.
Brain neurotransmitters in fatigue and overtraining
Authors: Meeusen Romain , Watson Philip , Hasegawa Hiroshi , Roelands Bart , Piacentini Maria F.
Published: April 2008

Since the publication of the serotonin hypothesis, numerous theories involving the accumulation or depletion of different substances in the brain have been proposed to explain central fatigue. Although the theoretical rationale for the “serotonin-fatigue hypothesis” is clear, several seemingly well-conducted studies have failed to support a significant role for 5-hydroxytryptamine in the development of fatigue. As brain function appears to be dependent upon the interaction of a number of systems, it is unlikely that a single neurotransmitter system is responsible for central fatigue. Several other mechanisms are involved, with evidence supporting a role for the brain catecholamines. Fatigue is therefore probably an integrated phenomenon, with complex interaction among central and peripheral factors. When prolonged and excessive training happens, concurrent with other stressors and insufficient recovery, performance decrements can result in chronic maladaptations that can lead to the overtraining syndrome (OTS). The mechanism of the OTS could be difficult to examine in detail, perhaps because the stress caused by excessive training load, in combination with other stressors, might trigger different “defence mechanisms” such as the immunological, neuroendocrine, and other physiological systems that all interact and probably therefore cannot be pinpointed as the “sole” cause of the OTS. It might be that, as in other syndromes, the psychoneuroimmunology (study of brain–behavior–immune interrelationships) might shed a light on the possible mechanisms of the OTS, but until there is a definite diagnostic tool, it is of utmost importance to standardize measures that are now thought to provide a good inventory of the training status of the athlete. It is very important to emphasize the need to distinguish the OTS from overreaching and other potential causes of temporary underperformance such as anemia, acute infection, muscle damage, and insufficient carbohydrate intake.
Effects of exercise on brain function: role of free radicals
Authors: Radak Zsolt , Kumagai Shuzo , Taylor Albert W. , Naito Hisashi , Goto Sataro
Published: April 2008

Reactive oxygen species (ROS) are continuously generated during aerobic metabolism. Certain levels of ROS, which could be dependent on the type of cell, cell age, history of ROS exposure, etc., could facilitate specific cell functions. Indeed, ROS stimulate a number of stress responses and activate gene expression for a wide range of proteins. It is well known that increased levels of ROS are involved in the aging process and the pathogenesis of a number of neurodegenerative diseases. Because of the enhanced sensitivity of the central nervous system to ROS, it is especially important to maintain the normal redox state in different types of neuro cells. In the last decade it became clear that regular exercise beneficially affects brain function as well, and can play an important preventive and therapeutic role in stroke and in Alzheimer’s and Parkinson’s diseases. The effects of exercise appear to be very complex and could include neurogenesis via neurotrophic factors, increased capillarization, decreased oxidative damage, and increased proteolytic degradation by proteasome and neprilysin. Data from our and other laboratories indicate that exercise-induced modulation of ROS levels plays a role in the protein content and expression of brain-derived neurotrophic factor, tyrosine recepetor kinase B, and cAMP response element binding protein, resulting in better function and increased neurogenesis. The enhanced activities of proteasome and neprilysin result in decreased accumulation of carbonyls and amyloid beta-proteins, as well as improved memory. It appears that exercise-induced modulation of the redox state is an important means by which exercise benefits brain function, increases the resistance against oxidative stress, and facilitates recovery from oxidative stress.
Ca2+/calmodulin-based signalling in the regulation of the muscle fibre phenotype and its therapeutic potential via modulation of utrophin A and myostatin expression
Authors: Michel Robin N. , Chin Eva R. , Chakkalakal Joe V. , Eibl Joe K. , Jasmin Bernard J.
Published: April 2008

Ca2+signalling plays an important role in excitation–contraction coupling and the resultant force output of skeletal muscle. It is also known to play a crucial role in modulating both short- and long-term muscle cellular phenotypic adaptations associated with these events. Ca2+signalling via the Ca2+/calmodulin (CaM)-dependent phosphatase calcineurin (CnA) and via Ca2+/CaM-dependent kinases, such as CaMKI and CaMKII, is known to regulate hypertrophic growth in response to overload, to direct slow versus fast fibre gene expression, and to contribute to mitochondrial biogenesis. The CnA- and CaMK-dependent regulation of the downstream transcription factors nuclear factor of activated T cells (NFAT) and myocyte-specific enhancer factor 2 are known to activate muscle-specific genes associated with a slower, more oxidative fibre phenotype. We have also recently shown the expression of utrophin A, a cytoskeletal protein that accumulates at the neuromuscular junction and plays a role in maturation of the postsynaptic apparatus, to be regulated by CnA–NFAT and Ca2+/CaM signalling. This regulation is fibre-type specific and potentiated by interactions with the transcriptional regulators and coactivators GA binding protein (also known as nuclear respiratory factor 2) and peroxisome proliferator-activated receptor-gamma coactivator 1 alpha. Another downstream target of CnA signalling may be myostatin, a transforming growth factor-β family member that is a negative regulator of muscle growth. While the list of the downstream targets of CnA/NFAT- and Ca2+/CaM-dependent signalling is emerging, the precise interaction of these pathways with the Ca2+-independent pathways p38 mitogen-activated protein kinase, extracellular signal-regulated kinases 1 and 2, phosphoinositide-3 kinase, and protein kinase B (Akt/PKB) must also be considered when deciphering fibre responses and plasticity to altered contractile load.
Effect of depth on flow over a fixed dune
Authors: Balachandar Ram , Hyun B.-S. , Patel V. C.
Published: April 2008

Laser Doppler velocimeter (LDV) measurements were carried out to study the effect of depth on the flow over a train of fixed two-dimensional dunes. Conventionally averaged velocity and turbulence parameters reveal large peaks in the streamwise and vertical components of turbulent intensities and shear stress, along the shear layer emanating from the dune crest. A secondary peak in the streamwise turbulence profiles some distance beyond the shear layer indicates maintenance of turbulence generated on the previous dune and convection of the flow history from one dune to the next. Analyses based on triple products and quadrant decomposition of velocity fluctuations reveals the central role of the shear layer in dictating the flow properties over the entire depth. The depth influences the flow in the near-bed region and the length of the separation zone is longer at a shallower depth. The streamwise mean profiles collapse onto a single curve in the outer region beyond the shear layer, indicating a degree of similarity and independence from the near-bed flow. The profiles of the vertical component of turbulence reveal a systematic dependence on flow depth, with lower turbulence intensity at larger depths. The quantitative effect of flow depth is evident in the measurements at all levels, including triple products and quadrant decomposition.
Modeling of freeway breakdown process with log-periodic oscillations
Authors: Bassan Shy , Polus Abishai , Faghri Ardeshir
Published: April 2008

Urban and suburban freeways are designed to allow smooth traffic flow at high speed. However, when traffic demand is high or during irregular events, significant congestion may develop. Traffic breakdown occurs during the phase transition from dense congested stable (DCS) flow to breakdown flow. In this study, the process of freeway flow breakdown was investigated by calibrating models in the density–time plane using morning peak data from Interstate 66, a US highway connecting Washington, D.C., and Virginia. It was shown that the models, which describe the collective behavior of drivers using the mathematical property of the log-periodic oscillations (LPO) process, reflect suitably the phase transition in freeway traffic flow. The LPO process has been used in the past to model stock market crashes and the occurrences of large earthquakes. The cyclic properties of the LPO models developd in this study were found to identify the “critical transition period,” which triggers the traffic breakdown process. This period starts when the density rate of change reaches its maximum during the first cycle that follows the DCS flow regime. This triggers a breakdown of flow conditions, which occur 5–8 min after the density rate of change has achieved its maximum.
Structural performance of rounded dovetail connections under different loading conditions
Authors: Tannert Thomas , Prion Helmut , Lam Frank
Published: April 2008

Test results on the structural performance of rounded dovetail connections (RDCs) under different loading conditions are reported. The RDCs are a versatile connection concept that is mainly used to transfer shear, but its geometry enables it to also resist other loading conditions. The connection capacity and the design load of two different connection configurations (single and double dovetail) produced from kiln-dried western hemlock (Tsuga heterophylla) in shear, tension, and bending tests were evaluated using analysis of variance. The shear tests demonstrated that RDC show linear elastic behaviour until they reach a load that leads to crack development. Connections with a single dovetail configuration provided higher tension capacity, while not showing significantly different structural performance than the double dovetail configuration under other loading conditions. The work demonstrated that RDCs also have considerable tension and bending resistance.
Optimum design of steel telecommunication poles using genetic algorithms
Authors: Khedr Mohamed A.H.
Published: April 2008

This study implements the genetic algorithm (GA) method in the optimization of steel telecommunication poles subjected to normal operating loads. In formulating the optimization problem, the objective function is defined as the pole weight. The imposed constraints on the design are: interaction ratios, sway angle limitations, minimum and maximum pole bottom diameters, and segment heights. The formulated problem is a mixed continuous–discrete problem where the main dimensions of the pole, top and bottom diameters, and segment heights are continuous variables whereas other variables are discrete. A Microsoft® Visual Basic® computer program is written implementing the requirements of TIA/EIA-222-G standards and using genetic algorithms (GAs). A verification problem and a generic telecommunication pole example are presented that show the effectiveness of the proposed approach. This program can be extended to cover other design standards of telecommunication poles as well as different types of poles, such as lighting and transmission poles.
Forest taxation in multiple-stand forestry with amenity preferences
Authors: Uusivuori Jussi , Kuuluvainen Jari
Published: April 2008

This paper investigates the impacts of forest taxes within an age-class forest model where the landowner derives utility from both consumption and the amenity values of standing forest. The model generalizes the existing models used to analyze forestry taxes. It is shown how the age-class model enables a more detailed analysis of the substitution and income effects of various taxes. These effects are shown to be linked to the properties of the utility function and to the distribution of the landowner’s assets between forests and nonforest assets. The results indicate that for most utility functions, income effect is unlikely to dominate the substitution effect of taxes on forest owner timber harvesting decisions. Numerical examples are used to demonstrate how the tax impacts can differ in the short run and long run. The results imply that higher consumption levels combined with profit or sales taxation applied in forestry will effectively reinforce each other in increasing optimal rotations. On the other hand, a lump-sum tax may be used to counteract the impact of increasing consumption levels.