bluuebunny/crossref_metadata_2025_split huggingface dataset:
Peroxisome Function Regulates Growth on Glucose in the Basidiomycete Fungus
Cryptococcus neoformans
Authors: Idnurm Alexander , Giles Steven S. , Perfect John R. , Heitman Joseph 
Published: January 2007

ABSTRACT

The function of the peroxisomes was examined in the pathogenic basidiomycete
Cryptococcus neoformans
. Recent studies reveal the glyoxylate pathway is required for virulence of diverse microbial pathogens of plants and animals. One exception is
C. neoformans
, in which isocitrate lyase (encoded by
ICL1
) was previously shown not to be required for virulence, and here this was extended to exclude also a role for malate synthase (encoded by
MLS1
). The role of peroxisomes, in which the glyoxylate pathway enzymes are localized in many organisms, was examined by mutation of two genes (
PEX1
and
PEX6
) encoding AAA (
A
TPases
a
ssociated with various cellular
a
ctivities)-type proteins required for peroxisome formation. The
pex1
and
pex6
deletion mutants were unable to localize the fluorescent DsRED-SKL protein to peroxisomal punctate structures, in contrast to wild-type cells.
pex1
and
pex6
single mutants and a
pex1 pex6
double mutant exhibit identical phenotypes, including abolished growth on fatty acids but no growth difference on acetate. Because both
icl1
and
mls1
mutants are unable to grow on acetate as the sole carbon source, these findings demonstrate that the glyoxylate pathway can function efficiently outside the peroxisome in
C. neoformans
. The
pex1
mutant exhibits wild-type virulence in a murine inhalation model and in an insect host, demonstrating that peroxisomes are not required for virulence under these conditions. An unusual phenotype of the
pex1
and
pex6
mutants was that they grew poorly with glucose as the carbon source, but nearly wild type with galactose, which suggested impaired hexokinase function and that
C. neoformans
peroxisomes might function analogously to the glycosomes of the trypanosomid parasites. Deletion of the hexokinase
HXK2
gene reduced growth in the presence of glucose and suppressed the growth defect of the
pex1
mutant on glucose. The hexokinase 2 protein of
C. neoformans
contains a predicted peroxisome targeting signal (type 2) motif; however, Hxk2 fused to fluorescent proteins was not localized to peroxisomes. Thus, we hypothesize that glucose or glycolytic metabolites are utilized in the peroxisome by an as yet unidentified enzyme or regulate a pathway required by the fungus in the absence of peroxisomes.
Molecular Systematics of Dictyostelids: 5.8S Ribosomal DNA and Internal Transcribed Spacer Region Analyses
Authors: Romeralo María , Escalante Ricardo , Sastre Leandro , Lado Carlos 
Published: January 2007

ABSTRACT

The variability and adaptability of the amoebae from the class
Dictyosteliomycetes
greatly complicate their systematics. The nucleotide sequences of the ribosomal internal transcribed spacers and the 5.8S ribosomal DNA gene have been determined for 28 isolates, and their utility to discriminate between different species and genera has been shown.
Protection against Cryptococcosis by Using a Murine Gamma Interferon-ProducingCryptococcus neoformansStrain
Authors: Wormley Floyd L. , Perfect John R. , Steele Chad , Cox Gary M. 
Published: January 2007

ABSTRACTWe evaluated cell-mediated immune (CMI) responses in mice given a pulmonary infection with aCryptococcus neoformansstrain engineered to produce the Th1-type cytokine gamma interferon (IFN-γ). Mice given a pulmonary infection with an IFN-γ-producingC. neoformansstrain were able to resolve the primary infection and demonstrated complete (100%) protection against a second pulmonary challenge with a pathogenicC. neoformansstrain. Pulmonary cytokine analyses showed that Th1-type/proinflammatory cytokine and chemokine expression were significantly higher and Th2-type cytokine expression was significantly lower in mice infected with the IFN-γ-producingC. neoformansstrain compared to wild-type-infected mice. This increased pulmonary Th1-type cytokine expression was also associated with significantly lower pulmonary fungal burden and significantly higher pulmonary leukocyte and T-lymphocyte recruitment in mice infected with the IFN-γ-producingC. neoformansstrain compared to wild-type-infected mice. Our results demonstrate that pulmonary infection of mice with aC. neoformansstrain expressing IFN-γ results in the stimulation of local Th1-type anti-cryptococcal CMI responses and the development of protective host immunity against future pulmonary cryptococcal infections. The use of fungi engineered to produce host cytokines is a novel method to study immune responses to infection and may be useful in developing vaccine strategies in humans.
Transcriptional and Proteomic Profiles of Group B
Streptococcus
Type V Reveal Potential Adherence Proteins Associated with High-Level Invasion
Authors: Johri Atul K. , Margarit Immaculada , Broenstrup Mark , Brettoni Cecilia , Hua Lei , Gygi Steven P. , Telford John L. , Grandi Guido , Paoletti Lawrence C. 
Published: January 2007

ABSTRACT

Group B
Streptococcus
(GBS) is an opportunistic organism that can harmlessly colonize the human gut, vagina, and rectum but can also cause pneumonia, sepsis, and meningitis in neonates born to colonized mothers. We have shown previously that growth rate and oxygen level regulate the ability of GBS to invade eukaryotic cells in vitro. Herein we extend and expand on these observations to show that GBS type V, an emergent serotype, grown in a chemostat at a cell mass-doubling time (

t
d

) of 1.8 h with oxygen invaded human ME-180 cervical epithelial cells in large numbers compared with those grown at the same

t
d

without oxygen or at a slower

t
d

of 11.0 h. The fact that several GBS type V cell wall-associated and membrane proteins were expressed exclusively under the invasive growth condition prompted an investigation, using genomics and proteomics, of all upregulated genes and proteins. Several proteins with potential roles in adherence were identified, including an undefined surface antigen (SAG1350), a lipoprotein (SAG0971), penicillin-binding protein 2b (SAG0765), glyceraldehyde-3-phosphate dehydrogenase (SAG0823), and an iron-binding protein (SAG1007). Mouse antisera to these five proteins inhibited binding of GBS type V to ME-180 cells by ≥85%. Recombinant undefined surface antigen (SAG1350), lipoprotein (SAG0971), and penicillin-binding protein 2b (SAG0765) each bound to ME-180 cells in a dose-dependent fashion, confirming their ability to act as ligands. Collectively, these data increase the number of potential GBS adherence factors and also suggest a role for these surface-associated proteins in initial pathogenic events.
Mixed epithelial and stromal tumour of the kidney with luteinised ovarian stroma
Authors: Buritica C , Serrano M , Zuluaga A , Arrabal M , Regauer S , Nogales F F 
Published: January 2007

We report a case of a 9-cm mixed epithelial and stromal tumour of the kidney in an obese 70-year-old woman with diabetes. The ovarian-type stroma had a spindle cell component that was positive for progesterone receptors and had the hitherto unreported presence of abundant foci of luteinised stromal cells with characteristic immunohistochemical positivity to α-inhibin, calretinin, aromatase and gonadotropin-releasing hormone (GnRH) receptors. We conclude that the stromal component is identical to ovarian cortical stroma.We believe that ovarian-type stroma occurs in extragenital tumours as a result of an epithelial–stromal interaction in an environment of hormonal hyperstimulation.
Immunohistological analysis of immune cells in blistering skin lesions
Authors: Hussein Mahmoud R , Ali Fayed Mahammad Nagy , Omar Abd-Elhady M M 
Published: January 2007

Background:Bullous skin lesions are characterised by the presence of intraepidermal or subepidermal bullae. Although inflammatory cell infiltrate is a constant feature in these lesions, their immunophenotypic characterisation is still incomplete.Aim:To determine whether the development of bullous skin diseases is associated with changes in the inflammatory cell infiltrate.Materials and methods:34 cases representing lesions with both intraepidermal and subepidermal bullae were examined using immunoperoxidase staining methods and antibodies targeting antigens for histiocytes (CD68), B cells (CD20+), T cells (CD3+), T cells with cytotoxic potential (T cell intracellular associated antigen, TIA1+) and activity (granzyme B, GRB+). The adjacent normal skin (lesions) and an additional five cases of normal skin were also examined (controls).Results:The transition from normal skin to lesional skin (lesions with intraepidermal and subepidermal bullae) was associated with a significant increase (p⩽0.05) in the density of total inflammatory cell infiltrate, CD68+ cells, CD3+ T lymphocytes, CD20+ B lymphocytes, TIA1+-resting cytotoxic T cells and GRB+ T cells with cytotoxic activity.Conclusions:The increase in inflammatory cell infiltrate during the transition from normal to lesional skin may reflect the presence of an increased antigenicity of the lesional cells or a response to some basement membrane components. CD68+ and CD3+ cells, especially the resting cytotoxic ones, achieved numerical dominance in these lesions. Cell-mediated immunity seems to have critical role in the development of these lesions.
Pulmonary oedema following exercise in humans
Authors: Hodges Alastair N.H. 
Published: January 2007

Sub-clinical transient pulmonary oedema has been observed following exercise in both animals and, to some degree, humans. It has been proposed that transient pulmonary oedema, resulting from either pulmonary capillary leakage or capillary stress failure, may limit diffusion in the lung during and after exercise. Initially, to determine the minimal tolerable FIO2 for subsequent work in hypoxia, 10 aerobically trained males (VO2 max, 57.2 ± 7.95 mL·kg–1·min–1; age, 29.6 ± 5.8 y; height, 181.1 ± 8.3 cm; mass, 79.4 ± 5.6 kg) performed graded cycling work to maximal effort under 4 conditions of varying FIO2 (21%, 18%, 15%, and 12%) in a randomized blinded fashion. VO2 max and minimal SaO2 were significantly reduced while breathing 15% and 12% oxygen (VO2 max, 48.2 ± 7.9 and 31.5 ± 7.4 mL·kg–1·min–1, respectively). In the 12% oxygen condition, the majority of the subjects were not able to complete maximal exercise without SaO2 falling below 70%. Subsequently, to determine if transient pulmonary oedema occurs after sustained exercise, 10 highly trained male athletes (VO2 max, 65.0 ± 7.5 mL·kg–1·min–1; age, 25.9 ± 4.7 y; height, 184.1 ± 8.2 cm; mass, 79.4 ± 9.5 kg) underwent assessment of lung density by quantified magnetic resonance imaging before and 54.0 ± 17.2 and 100.7 ± 15.1 min after 60 min of cycling exercise (61.6% ± 9.5% VO2 max). The same 10 subjects underwent an identical measure before and 55.6 ± 9.8 and 104.3 ± 9.1 min after 60 min of cycling exercise (65.4% ± 7.1% hypoxic VO2 max) in hypoxia (FIO2 = 15.0%). Two subjects demonstrated mild exercise-induced arterial hypoxaemia (EIAH) (minSaO2 = 94.5% and 93.8%), and 7 demonstrated moderate EIAH (minSaO2 = 91.4% ± 1.1%) during a preliminary VO2 max test in normoxia. No significant differences (p < 0.05) were found in lung density after exercise in either condition. Mean lung densities, measured once pre- and twice post-exercise, were 0.177 ± 0.019, 0.181 ± 0.019, and 0.173 ± 0.019 g·mL–1 in the normoxic condition, and 0.178 ± 0.021, 0.174 ± 0.022, and 0.176 ± 0.019 g·mL–1 in the hypoxic condition. These results indicate that transient interstitial pulmonary oedema does not occur following sustained steady-state cycling exercise in normoxia or hypoxia. This diminishes the likelihood of pulmonary capillary leakage as a mechanism of transient pulmonary oedema, and, in turn, as a mechanism for changes in SaO2 during sustained exercise.
Work of breathing is increased during exercise with the self-contained breathing apparatus regulator
Authors: Butcher Scott J. , Jones Richard L. , Eves Neil D. , Petersen Stewart R. 
Published: January 2007

The self-contained breathing apparatus (SCBA) increases the expiratory pressure required to maintain high rates of ventilation, suggesting that the expiratory work of breathing (WOB) is increased; however, this has never been reported. The objective of this study, therefore, was to determine if the WOB is increased with the SCBA regulator (BA condition) compared with a low-resistance breathing valve (RV condition) during exercise. Twelve healthy male subjects underwent two randomized exercise trials, consisting of cycling at 150, 180, 210, and 240 W. Inspired and expired tidal volumes were measured using a body plethysmograph, whereas esophageal pressures were measured with an esophageal balloon. Modified Campbell diagrams were created to calculate the resistive and elastic components of WOB during inspiration and expiration. There were no differences in WOB between BA and RV conditions at 150 W. End-inspiratory and -expiratory lung volumes were elevated (p < 0.05) in the BA condition at higher ventilation rates, which increased inspiratory elastic work and decreased expiratory elastic work at 180 and 210 W (p < 0.05). At 240 W (VE = 112 ± 17 L·min–1 in the BA condition), active expiratory resistive work increased by 59% ± 51%, inspiratory elastic work increased by 26% ± 24%, and total WOB increased by 13% ± 12% in the BA condition (p < 0.05). The SCBA regulator causes an increase in the active expiratory resistive work to maintain high ventilatory rates and an increase inspiratory elastic work through an elevation in lung volumes.
Local cold acclimation during exercise and its effect on neuromuscular function of the hand
Authors: Geurts Carla L.M. , Sleivert Gordon G. , Cheung Stephen S. 
Published: January 2007

Most acclimation research is performed on resting individuals, whereas in real life, cold exposure is often accompanied by physical activity. We examined the effects of 2 weeks of repeated cold exposure of the hand with or without an elevated core temperature from exercise on neuromuscular function of the first dorsal interosseus (FDI) muscle and manual performance of the hand. The experimental group (4 female, 6 male; age, 25.1 ± 6.9 y) cooled their hands in 8 °C water for 30 min daily while cycling (50% of heart rate reserve); the control group (4 female, 4 male; age, 25.1 ± 5.7 y) remained still. Manual function testing consisted of tactile sensitivity, grip strength, manual dexterity, and evoked twitch force in a custom-made myograph. Thermal sensation, skin temperature of index finger (Tif) and hand (Tfdi), as well as rectal temperature (Tre), were recorded daily. Tre increased significantly during bicycling, by 0.6 ± 0.2 °C. Minimal Tif and Tfdi of the groups combined increased significantly during exposure days from 8.7 ± 0.7 °C and 12.4 ± 2.8 °C to 10.1 ± 1.3 °C and 15.0 ± 3.0 °C, respectively (p = 0.04), with no significant difference between groups. Thermal ratings improved significantly on exposure days. Manual function was impaired with cooling, but with no significant difference between groups or across time. Deterioration of twitch characteristics with cooling did not change with repeated cold exposure. Although the increasing core temperature during cold water immersion changed the acute temperature response and thermal ratings, it had no effect on local cold acclimation or manual function.
Validity of the 3 min step test in moderate altitude: environmental temperature as a confounder
Authors: Chen Shu-Man , Wang Jung-Shi , Lee Wen-Chih , Hou Chien-Wen , Chen Chung-Yu , Laio Yi-Hung , Lin Ching-Hung , Kuo Chia-Hua 
Published: January 2007

The 3 min step test is a widely used method to evaluate physical fitness, but whether this method is valid when performed at altitude is unknown. The purpose of this study was to examine the effect of altitude on the fitness score of the 3 min step test, and the role of ambient temperature in this effect. In study I, 11 healthy volunteers (aged 18.1 ± 1.1 years) performed a 3 min step test at sea level and at altitude (1950 m). Plasma lactate and stress hormones, as indicators of metabolic stress, were measured before and after the test. To determine the role of ambient temperature, we performed study II at sea level with the same step test simulating the altitude temperature condition (24 °C at high altitude versus 32 °C at sea level) with 23 subjects (aged 20.4 ± 0.4 y). In study I, plasma lactate of the subjects was elevated during the step test at sea level and to a greater extent at high altitude. Plasma cortisol and testosterone levels were elevated only at high altitude. However, the heart rate (HR) recovery after the step test was faster at high altitude than at sea level, producing a better physical fitness index. Furthermore, in study II, we demonstrated that the subjects who performed the 3 min step test at 24 °C exhibited faster HR recovery than at 32 °C. The current study therefore suggests that environmental conditions leading to temperature variation have strong confounding effects on the fitness score of the 3 min step test.
Dietary intakes of Canadians in the 1990s using population-weighted data derived from the provincial nutrition surveys
Authors: Dolega-Cieszkowski Jadwiga H. , Bobyn Joan P. , Whiting Susan J. 
Published: January 2007

Provincial nutrition surveys of adults were conducted between 1990 and 1999 in Canada. Eight reports have been issued, and one is forthcoming. The purpose of this study was to estimate the national dietary intake of adult Canadians, using the publicly available data. Group mean-nutrient-intake data from 16 915 adults, aged 18 to 84 years, from published provincial reports were collated by age and sex for each of 9 provinces (Manitoba data were unavailable). Using Canadian census data appropriate to the year of collection, intake data were weighted to provide 1 national intake value for each nutrient, by 8 age and sex categories. In general, the energy and nutrient intake of adults decreased with age. For every age group, with the exception of vitamin C, intake of nutrients by men was greater than that by women. On the basis of a comparison of recently recommended intakes (Dietary Reference Intakes), the nutrients that are of concern because of inadequate intake include dietary fibre, calcium, magnesium, and folate. The data demonstrate the impact of folate fortification on folate intake; the mean intake became twice that of prefortification levels. This study used group mean-intake data; therefore, we cannot make definitive conclusions about the prevalence of inadequacy for the nutrients. Because of limitations with some provincial response rates, our data should not be construed as representative of the Canadian population. However, because these surveys were completed between the 19701972 Nutrition Canada Survey and the 2004 Canadian Community Health Survey, these population-weighted data might be a useful point of comparison for monitoring trends in nutrient intake from food.
Loving Mac, Beth, and John: Grace in the Plays and Films of Horton Foote
Authors: Wood Gerald 
Published: January 2007

AbstractHorton Foote is neither a rhetorical nor a polemical writer. He is a story-teller who uses his home place, Wharton, Texas, as the basis of his plays and films. But Foote instinctively uses the point of view of his religious tradition, Christian Science, in the subtext of many of his works. In the film Tender Mercies, for example, God's will is expressed as the peace and order found in shared love, like that of Rosa Lee for Mac. The goal of such divinity is a human community based on passionate, selfless care for others, as imagined in the feelings of the town toward Beth in the play The Carpetbagger's Children. Even when such mutuality is unrealized, grace remains as the spiritual presence which comforts John at the end of the teleplay Alone. Such an interpretation of grace follows the view of Christian Science that God is never manipulative, punishing, or violent. It places Foote in a tradition which emphasizes sanctification rather than justification, as defined by Reinhold Niebuhr. Closest theologically to Paul Tillich, Teilhard de Chardin, and especially Karl Rahner, Foote imagines time as the means by which God expresses infinite love.
Methane Emissions from Natural Wetlands in the United States: Satellite-Derived Estimation Based on Ecosystem Carbon Cycling
Authors: Potter Christopher , Klooster Steven , Hiatt Seth , Fladeland Matthew , Genovese Vanessa , Gross Peggy 
Published: January 2007

Abstract
Wetlands are an important natural source of methane to the atmosphere. The amounts of methane emitted from inundated ecosystems in the United States can vary greatly from area to area. Seasonal temperature, water table dynamics, and carbon content of soils are principal controlling factors. To calculate the effect of wetlands (and their potential conversion to other land uses) on global greenhouse gas emissions, information on area covered by various wetland types is needed, along with verified projections of spatial variation in net methane emissions. Both of these variables are poorly known, and estimates are largely unavailable at the country level. Nationwide satellite datasets for the coterminous United States (excluding Alaska) have been combined with ecosystem model predictions of monthly net carbon exchange with the atmosphere to produce the first detailed mapping of methane fluxes from natural wetlands on a monthly and annual basis. The Carnegie–Ames–Stanford Approach (CASA) model’s predicted mean emission flux of methane from wetlands of the continental United States totaled 5.5 Tg CH4 per year. Ranked in terms of total annual flux, the 10 states with the highest predicted emissions (not considering Alaska) are all located in the Great Lakes region and the southern coastal regions of the country.
Assertive rehabilitation for intracapsular fracture of the proximal femur
Authors: Ohsawa Suguru , Miura Aiko , Yagyu Mie , Oizumi Anzu , Yamada Eiji 
Published: January 2007

Objective: To study the impact of assertive conservative therapy on walking in frail elderly patients with intracapsular fracture of the proximal femaur. Design: Prospective non-randomized controlled trial. Setting: Two private geriatric rehabilitation hospitals. Subjects: From October 1997 to December 2004, 20 patients, not indicated for surgery, were treated with conservative therapy. There were 18 women and 2 men, and their ages were 87.1±4.2 (mean ±SD) years. All of them could walk before hip fracture. Interventions: Thirteen patients accepted our assertive therapy, which consisted of standing on the fractured limb and walking in parallel bars as soon as possible. Seven patients refused our methods and were conventionally treated; the injured limb was immobilized under skin traction, and then they gradually tried to use a wheelchair for pain reduction. Main measures: We used the following measures before therapy and six months after: Merle d'Aubigné & Postel's Hip Score, Functional Independence Measure (FIM) and face pain scale. Results: The two groups were similar demographically. All patients except one (n = 12) responded to our method and could walk. However, the patients treated with the conventional method (n = 7) did not recover the ability to walk. The mean FIM (transfer and locomotion, five items) was 18.2 ±7.9 points in the former and 9.4 ± 4.3 points in the latter. Conclusion: Assertive rehabilitation was more effective at restoring the ambulatory ability of frail elderly patients with intracapsular fracture of the hip than the conventional method.