bluuebunny/crossref_metadata_2025_split huggingface dataset:
Glucosyltransferases of Viridans Group Streptococci Modulate Interleukin-6 and Adhesion Molecule Expression in Endothelial Cells and Augment Monocytic Cell Adherence
Authors: Yeh Chiou-Yueh , Chen Jen-Yang , Chia Jean-San 
Published: January 2006

ABSTRACTRecruitment of monocytes plays important roles during vegetation formation and endocardial inflammation in the pathogenesis of infective endocarditis (IE). Bacterial antigens or modulins can activate endothelial cells through the expression of cytokines or adhesion molecules and modulate the recruitment of leukocytes. We hypothesized that glucosyltransferases (GTFs), modulins of viridans group streptococci, may act directly to up-regulate the expression of adhesion molecules and also interleukin-6 (IL-6) to augment monocyte attachment to endothelial cells. Using primary cultured human umbilical vein endothelial cells (HUVECs) as an in vitro model, we demonstrated that GTFs (in the cell-bound or free form) could specifically modulate the expression of IL-6, and also adhesion molecules, in a dose- and time-dependent manner. Results of inhibition assays suggested that enhanced expression of adhesion molecules was dependent on the activation of nuclear factor κB (NF-κB) and extracellular signal-regulated kinase and that p38 mitogen-activated protein kinase pathways also contributed to the release of IL-6. Streptococcus-infected HUVECs or treatment with purified IL-6 plus soluble IL-6 receptor α enhanced the expression of ICAM-1 and the adherence of the monocytic cell line U937. These results suggest that streptococcal GTFs might play an important role in recruiting monocytic cells during inflammation in IE through induction of adhesion molecules and IL-6, a cytokine involved in transition from neutrophil to monocyte recruitment.
Naturally Elicited Antibodies to Glycosylphosphatidylinositols (GPIs) of
Plasmodium falciparum
Require Intact GPI Structures for Binding and Are Directed Primarily against the Conserved Glycan Moiety
Authors: Naik Ramachandra S. , Krishnegowda Gowdahalli , Ockenhouse Christian F. , Gowda D. Channe 
Published: January 2006

ABSTRACT

Immunization with a synthetic glycan corresponding to
Plasmodium falciparum
glycosylphosphatidylinositols (GPIs) has been proposed as a vaccination strategy against malaria. We investigated the structural requirements for binding of naturally elicited anti-GPI antibodies to parasite GPIs. The data show that anti-GPI antibody binding requires intact GPI structures and that the antibodies are directed predominantly against GPIs with a conserved glycan structure with three mannoses and marginally against the terminal fourth mannose. The results provide valuable insight for exploiting GPIs for the development of malaria vaccines.
Immune Responses Induced in Cattle by Vaccination with a Recombinant Adenovirus Expressing Mycobacterial Antigen 85A and
Mycobacterium bovis
BCG
Authors: Vordermeier H. Martin , Huygen Kris , Singh Mahavir , Hewinson R. Glyn , Xing Zhou 
Published: January 2006

ABSTRACT

Cattle were vaccinated with an adenovirus expressing the mycobacterial antigen 85A (rAd85A), with
Mycobacterium bovis
BCG followed by rAd85A heterologous boosting, or with rAd85A followed by BCG boosting. BCG/rAd85A resulted in the highest direct gamma interferon responses. Cultured enzyme-linked immunospot assay analysis demonstrated that memory responses were induced by all three protocols but were strongest after BCG/rAd85A and rAd85A/BCG vaccination.
Clearance of EntericSalmonella entericaSerovar Typhimurium in Chickens Is Independent of B-Cell Function
Authors: Beal Richard K. , Powers Claire , Davison T. Fred , Barrow Paul A. , Smith Adrian L. 
Published: January 2006

ABSTRACTSalmonella entericaserovar Typhimurium colonizes the gut of chickens and is cleared from the intestine within about 3 weeks. Infection induces high levels of specific antibody, but B cells do not play an essential role in clearance of primary infection or in the enhanced clearance after secondary challenge.
Toll-Like Receptor 4 Protects against LethalLeptospira interrogansSerovar Icterohaemorrhagiae Infection and Contributes to In Vivo Control of Leptospiral Burden
Authors: Viriyakosol Suganya , Matthias Michael A. , Swancutt Mark A. , Kirkland Theo N. , Vinetz Joseph M. 
Published: January 2006

ABSTRACTThe roles of innate immune responses in protection from or pathogenesis of severe leptospirosis remain unclear. We examined the role of Toll-like receptors (TLRs) in mouse infection and macrophage responses toLeptospira. C3H/HeJ mice (TLR4 deficient) and C3H/HeJ-SCID mice, but not C3H/OuJ mice (TLR4 intact), died after intraperitoneal infection withLeptospira interrogansserovar Icterohaemorrhagiae. Death in both C3H/HeJ mouse strains was associated with jaundice and pulmonary hemorrhage, similar to the patient from whom the isolate was obtained. In chronic sublethal infection, TLR4-deficient mice harbored more leptospires in liver, lung, and kidney than control mice. Heat-killedLeptospirastimulated macrophages to secrete proinflammatory cytokines, tumor necrosis factor alpha, interleukin-6, and macrophage inflammatory protein 2 not inhibited by polymyxin B, suggesting that leptospiral lipopolysaccharide (LPS) did not drive these responses. Anti-TLR4 and anti-MD-2 but not anti-CD14 monoclonal antibodies inhibited cytokine production. Peritoneal macrophages from CD14−/−and TLR2−/−mice exhibited no defect in cytokine responses toLeptospiracompared to controls. Macrophages from C3H/HeJ, TLR4−/−, and MyD88−/−mice secreted far-lower levels of cytokines than wild-type macrophages in response toLeptospira. TLR4 plays a crucial role in protection from acute lethal infection and control of leptospiral burden during sublethal chronic infection. Cytokine responses in macrophages correlated with leptospiral clearance. These TLR4-dependent but CD14/TLR2-independent responses are likely mediated by a leptospiral ligand(s) other than LPS.
The ProtozoanNeospora caninumDirectly Triggers Bovine NK Cells To Produce Gamma Interferon and To Kill Infected Fibroblasts
Authors: Boysen Preben , Klevar Siv , Olsen Ingrid , Storset Anne K. 
Published: January 2006

ABSTRACTNatural killer (NK) cells are considered to be key players in the early innate responses to protozoan infections, primarily indirectly by producing gamma interferon (IFN-γ) in response to cytokines, like interleukin 12 (IL-12). We demonstrate that live, as well as heat-inactivated, tachyzoites ofNeospora caninum, aToxoplasma-like protozoan, directly trigger production of IFN-γ from purified, IL-2-activated bovine NK cells. This response occurred independently of IL-12 but was increased by the addition of the cytokine. A similar IFN-γ response was measured in cocultures of NK cells andN. caninum-infected autologous fibroblasts. However, no NK cell-derived IFN-γ response was detected when cells were cultured with soluble antigens from the organism, indicating that intact tachyzoites or nonsoluble components are necessary for NK cell triggering. Furthermore,N. caninum-infected autologous fibroblasts had increased susceptibility to NK cell cytotoxicity compared to uninfected fibroblasts. This cytotoxicity was largely mediated by a perforin-mediated mechanism. The activating receptor NKp46 was involved in cytotoxicity against fibroblasts but could not explain the increased cytotoxicity against infected targets. Interestingly,N. caninumtachyzoites were able to infect cultured NK cells, in which tachyzoites proliferated inside parasitophorous vacuoles. Together, these findings underscore the role of NK cells as primary responders during a protozoan infection, describe intracellular protozoan infection of NK cells in vitro for the first time, and represent the first functional study of purified bovine NK cells in response to infection.
Comparative Safety and Immunogenicity of Two Attenuated Enterotoxigenic
Escherichia coli
Vaccine Strains in Healthy Adults
Authors: McKenzie Robin , Bourgeois A. Louis , Engstrom Fayette , Hall Eric , Chang H. Sunny , Gomes Joseph G. , Kyle Jennifer L. , Cassels Fred , Turner Arthur K. , Randall Roger , Darsley Michael , Lee Cynthia , Bedford Philip , Shimko Janet , Sack David A. 
Published: January 2006

ABSTRACT

A vaccine against enterotoxigenic
Escherichia coli
(ETEC) is needed to prevent diarrheal illness among children in developing countries and at-risk travelers. Two live attenuated ETEC strains, PTL002 and PTL003, which express the ETEC colonization factor CFA/II, were evaluated for safety and immunogenicity. In a randomized, double-blind, placebo-controlled trial, 19 subjects ingested one dose, and 21 subjects ingested two doses (days 0 and 10) of PTL-002 or PTL-003 at 2 × 10
9
CFU/dose. Anti-CFA/II mucosal immune responses were determined from the number of antibody-secreting cells (ASC) in blood measured by enzyme-linked immunospot assay, the antibody in lymphocyte supernatants (ALS) measured by enzyme-linked immunosorbent assay (ELISA), and fecal immunoglobulin A (IgA) levels determined by ELISA. Time-resolved fluorescence (TRF) ELISA was more sensitive than standard colorimetric ELISA for measuring serum antibody responses to CFA/II and its components, CS1 and CS3. Both constructs were well tolerated. Mild diarrhea occurred after 2 of 31 doses (6%) of PTL-003. PTL-003 produced more sustained intestinal colonization than PTL-002 and better IgA response rates: 90% versus 55% (
P
= 0.01) for anti-CFA/II IgA-ASCs, 55% versus 30% (
P
= 0.11) for serum anti-CS1 IgA by TRF, and 65% versus 25% (
P
= 0.03) for serum anti-CS3 IgA by TRF. Serum IgG response rates to CS1 or CS3 were 55% in PTL-003 recipients and 15% in PTL-002 recipients (
P
= 0.02). Two doses of either strain were not significantly more immunogenic than one. Based on its superior immunogenicity, which was comparable to that of a virulent ETEC strain and other ETEC vaccine candidates, PTL-003 will be developed further as a component of a live, oral attenuated ETEC vaccine.
Effect of lower limb massage on electromyography and force production of the knee extensors
Authors: Hunter A M , Watt J M , Watt V , Galloway S D R 
Published: January 2006

Objective:To evaluate the effect of massage on force production and neuromuscular recruitment.Methods:Ten healthy male subjects performed isokinetic concentric contractions on the knee extensors at speeds of 60, 120, 180, and 240°/s. These contractions were performed before and after a 30 minute intervention of either rest in the supine position or lower limb massage. Electromyography (EMG) and force data were captured during the contractions.Results:The change in isokinetic mean force due to the intervention showed a significant decrease (p<0.05) at 60°/s and a trend for a decrease (p  =  0.08) at 120°/s as a result of massage compared with passive rest. However, there were no corresponding differences in any of the EMG data. A reduction in force production was shown at 60°/s with no corresponding alteration in neuromuscular activity.Conclusions:The results suggests that motor unit recruitment and muscle fibre conduction velocity are not responsible for the observed reductions in force. Although experimental confirmation is necessary, a possible explanation is that massage induced force loss by influencing “muscle architecture”. However, it is possible that the differences were only found at 60°/s because it was the first contraction after massage. Therefore muscle tension and architecture after massage and the duration of any massage effect need to be examined.
Live high-train low associated with increased haemoglobin mass as preparation for the 2003 World Championships in two native European world class runners
Authors: Wehrlin J P , Marti B 
Published: January 2006

Background:It is unclear whether world class endurance athletes, in contrast with less well trained subjects, increase their haemoglobin mass on a regimen of living high and training low (LHTL).Objective:To assess whether haemoglobin mass increases in world class athletes on LHTL and whether this increase is associated with peak performance at a subsequent important competition.Methods:Two Swiss world class runners (one 5000 m and one marathon) lived for 26 days (18 hours a day) at an altitude of 2456 m and trained at 1800 m. This LHTL camp was the preparation for the World Athletic Championships taking place 27–29 days after the end of the camp. Haemoglobin mass and other haematological variables were measured before and after the LHTL camp. The performance parameter was the race times during that period.Results:Haemoglobin mass increased by 3.9% and 7.6%, and erythrocyte volume by 5.8% and 6.3%. The race times, as well as the ranking at the World Championships, indicated clearly improved performance after the LHTL camp.Conclusions:The results suggest that LHTL with an adequate dose of hypoxia can increase haemoglobin mass even in world class athletes, which may translate into improved performance at important competitions at sea level.
Growth hormone 1 (GH1) gene and performance and post-race rectal temperature during the South African Ironman triathlon
Authors: Walpole B , Noakes T D , Collins M 
Published: January 2006

Background:Some studies have suggested that the insertion allele of theACEgene is associated with endurance performance, including the Ironman triathlon. It is possible that this association is due to genetic linkage between theACEI/D locus and the T/A variant in intron 4 of the neighbouringGH1gene. The A variant is associated with lower levels of growth hormone production. Growth hormone has multiple effects, especially on metabolism during exercise and recovery from exercise. Its production during exercise has also been shown to stimulate sweat rate and heat loss.Objective:To determine whether theGH1gene is associated with the performance and/or post-race rectal temperatures of competitors in the South African Ironman triathlon.Methods:A total of 169 of the fastest finishing white male triathletes who completed the 2000 and/or 2001 South African Ironman triathlon and 155 control subjects were genotyped for the T/A variant in theGH1gene. Post-race rectal temperature was also determined in 103 of these triathletes.Results:There was no significant difference in the frequency of this polymorphism in theGH1gene when the fastest finishing triathletes were compared with the control subjects. Post-race rectal temperatures were, however, significantly higher in those triathletes with an AA genotype (mean (SD) 37.7 (0.8)°C) compared with those with a TT genotype (37.2 (0.8)°C) (p  =  0.019).Conclusions:The T/A polymorphism in intron 4 of theGH1gene was not associated with performance of the fastest finishers of the South African Ironman triathlon. Post-race rectal temperatures were, however, significantly higher in the fastest finishing athletes, who were homozygous for aGH1genotype associated with lower growth hormone production.
High risk of new knee injury in elite footballers with previous anterior cruciate ligament injury
Authors: Waldén M , Hägglund M , Ekstrand J 
Published: January 2006

Background:Anterior cruciate ligament (ACL) injury is a severe event for a footballer, but it is unclear if the knee injury rate is higher on returning to football after ACL injury.Objective:To study the risk of knee injury in elite footballers with a history of ACL injury compared with those without.Method:The Swedish male professional league (310 players) was studied during 2001. Players with a history of ACL injury at the study start were identified. Exposure to football and all time loss injuries during the season were recorded prospectively.Results:Twenty four players (8%) had a history of 28 ACL injuries in 27 knees (one rerupture). These players had a higher incidence of new knee injury of any type than the players without ACL injury (mean (SD) 4.2 (3.7)v1.0 (0.7) injuries per 1000 hours, p  =  0.02). The risk of suffering a knee overuse injury was significantly higher regardless of whether the player (relative risk 4.8, 95% confidence interval 2.0 to 11.2) or the knee (relative risk 7.9, 95% confidence interval 3.4 to 18.5) was used as the unit of analysis. No interactive effects of age or any other anthropometric data were seen.Conclusion:The risk of new knee injury, especially overuse injury, was significantly increased on return to elite football after ACL injury regardless of whether the player or the knee was used as the unit of analysis.
No holds barred sport fighting: a 10 year review of mixed martial arts competition
Authors: Buse G J 
Published: January 2006

Objective:To identify the most salient medical issues that may be associated with mixed martial arts competition by determining the types and proportions of match stoppages.Methods:Publicly available video footage of 1284 men competing in 642 consecutive televised matches from November 1993 to November 2003 was reviewed to determine the reasons for which matches were stopped. Matches were sanctioned by either a United States or Japan based mixed martial arts organisation.Results:Of the 642 matches, 182 (28.3±3.4%) were stopped because of head impact, 106 (16.5±2.9%) because of musculoskeletal stress, 91 (14.1±2.7%) because of neck choke, 83 (12.9±2.6%) because of miscellaneous trauma, 173 (27.0±3.4%) because of expiration of match time, and seven (1.0±0.8%) because of disqualification, where the values in parentheses are percentages±95% confidence interval.Conclusions:Blunt force to the head resulted in the highest proportion of match stoppages. Further research is warranted to delineate the morbidity associated with participation in mixed martial arts.
Thermoregulatory observations in soccer match play: professional and recreational level applications using an intestinal pill system to measure core temperature
Authors: Edwards A M , Clark N A 
Published: January 2006

Background:Technological limitations associated with oesophageal and rectal temperature probes have previously limited match play observations of body temperature.Objective:To investigate the application of an intestinal pill system to measure core temperature during dynamic, field based, soccer matches.Methods:Core temperature (Tc) was assessed using the intestinal pill system (CorTemp 2000) and changes in plasma volume were calculated using the values for haemoglobin and packed cell volume obtained before and after recreational (n = 8) and the professional soccer (n = 7) matches.Results:In the recreational match, there were significant post-match reductions in body mass (−1.6%, p<0.05) and plasma volume (−7.2%, p<0.01). Significant increases were observed inTcfrom rest to half time (p<0.01) and from half time to full time (p<0.05). In the professional match, body mass decreased by 1.9% (p<0.05) and plasma volume by 11.6% (p<0.01).Tcincreased from rest to half time (p<0.01) but was unchanged from half time to full time. Significant associations were observed between maximum oxygen consumption and match play heart rates in the second half of each match but these were not related to changes in plasma volume orTc.Conclusions:Intestinal temperature proved a useful method of recording core temperature during soccer match play and assisted in the measurement of alterations in thermoregulatory variables in response to both professional and recreational level soccer matches; however, technological limitations still restrict the wider application of this method, especially at a competitive level.
Dose–response relation between physical activity and sick leave
Authors: Proper K I , van den Heuvel S G , De Vroome E M , Hildebrandt V H , Van der Beek A J 
Published: January 2006

Objective:To investigate the dose–response relation between moderate and vigorous physical activity and sick leave in a working population.Methods:Data were used from three large Dutch databases: two continuous, cross sectional surveys among a representative sample of the Dutch population and one prospective cohort study. A distinction was made between duration, frequency and intensity of physical activity. The outcome measure was the number of days of sick leave. Analyses of variance were used to compare sick leave (in days) for workers with different amounts of physical activity, in particular workers meeting the physical activity recommendationsvthose who did not. Linear and logistic regression analyses were used to obtain effect estimates in the prospective cohort study, with the generalised estimating equation (GEE) method.Results:No relation was found between moderate physical activity and sick leave. In two databases, workers meeting the recommendation of vigorous physical activity (active at a vigorous level for at least three times a week) had significantly less sick leave: more than one day over two months and more than four days over a year. The duration of vigorous physical activity was not associated with sick leave.Conclusion:Physical activity at a vigorous intensity level for at least three times a week, as in the CDC/ACSM recommendation, has a positive effect on sick leave.
A newly described plant disease complex involving two distinct viruses in a native Alaskan lily,Streptopus amplexifolius
Authors: Robertson N.L. 
Published: January 2006

The etiology of a previously unknown disease of Streptopus amplexifolius (L.) DC. (twisted stalk) that occurred in south central Alaska was elucidated. Symptomatic plants with yellow-green dashes and streaks on their leaves contained distinct viruses belonging to the family Potyviridae and (or) tentatively to the family Flexiviridae genus Carlavirus . Each virus’ identity was confirmed by a combination of morphology, serology (ELISA and (or) Western analysis), and sequences obtained from reverse transcriptase – polymerase chain reaction products previously generated by potyvirus- or carlavirus-specific primers. The mechanical transmission of particles (purified from twisted stalk as a mixture of both viruses or as a single preparation of each virus) to S. amplexifolius, Chenopodium amaranticolor Coste et Reyn, and Chenopodium quinoa Willd., fulfilled Koch’s postulates. The relatively high incidence of infected plants and associated severe symptoms in populations from several sites in south central Alaska gave evidence that native plants are susceptible to, and are adversely affected by viral diseases. Even though Streptopus species grow throughout the temperate regions of the world, this is the first report of a pathogen(s) infecting plants in the genus Streptopus.
Diurnal cycle of sparteine production in Lupinus arcticus
Authors: Sharam Gregory J. , Turkington Roy 
Published: January 2006

Sparteine is a neurological toxin found in arctic lupine ( Lupinus arcticus S. Wats.) and is probably used as a defensive chemical to deter herbivory, particularly by snowshoe hares ( Lepus americanus Erxleben). Lupine leaves were collected in southwestern Yukon at 2 h intervals for 2 consecutive days at the peak of the growing season (24–25 June), and their sparteine was extracted and compared with a standard using gas chromatography. A significant daily cycle of sparteine in leaf material was observed, with maximum concentrations occurring during the night and minimum during the afternoon. This may be a temporally optimal response to higher levels of hare herbivory that occur at night.