Predictors of severe trunk postures among short-haul truck drivers during non-driving tasks: an exploratory investigation involving video-assessment and driver behavioural self-monitoring

Short-haul truck (lorry) drivers are particularly vulnerable to back pain and injury due to exposure to whole body vibration, prolonged sitting and demanding material handling tasks. The current project reports the results of video-based assessments (711 stops) and driver behavioural self-monitoring (BSM) (385 stops) of injury hazards during non-driving work. Participants (n = 3) worked in a trailer fitted with a camera system during baseline and BSM phases. Descriptive analyses showed that challenging customer environments and non-standard ingress/egress were prevalent. Statistical modelling of video-assessment results showed that each instance of manual material handling increased the predicted mean for severe trunk postures by 7%, while customer use of a forklift, moving standard pallets and moving non-standard pallets decreased predicted means by 12%, 20% and 22% respectively. Video and BSM comparisons showed that drivers were accurate at self-monitoring frequent environmental conditions, but less accurate at monitoring trunk postures and rare work events. The current study identified four predictors of severe trunk postures that can be modified to reduce risk of injury among truck drivers and showed that workers can produce reliable self-assessment data with BSM methods for frequent and easily discriminated events environmental.

Penicillin-binding protein 7/8 contributes to the survival of Acinetobacter baumannii in vitro and in vivo

BACKGROUND

Acinetobacter baumannii is a bacterial pathogen of increasing medical importance. Little is known about genes important for its survival in vivo.

METHODS AND RESULTS

Screening of random transposon mutants of the model pathogen AB307-0294 identified the mutant AB307.27. AB307.27 contained its transposon insertion in pbpG, which encodes the putative low-molecular-mass penicillin-binding protein 7/8 (PBP-7/8). AB307.27 was significantly killed in ascites (P<.001), but its growth in Luria-Bertani broth was similar to that of its parent, AB307-0294 (P=.13). The survival of AB307.27 was significantly decreased in a rat soft-tissue infection model (P<.001) and a rat pneumonia model (P=.002), compared with AB307-0294. AB307.27 was significantly killed in 90% human serum in vitro, compared with AB307-0294 (P<.001). Electron microscopy demonstrated more coccobacillary forms of AB307.27, compared with AB307-0294, suggesting a possible modulation in the peptidoglycan, which may affect susceptibility to host defense factors.

CONCLUSIONS

These findings demonstrate that PBP-7/8 contributes to the pathogenesis of A. baumannii. PBP-7/8 either directly or indirectly contributes to the resistance of AB307-0294 to complement-mediated bactericidal activity. An understanding of how PBP-7/8 contributes to serum resistance will lend insight into the role of this low-molecular-mass PBP whose function is poorly understood.

Capsular polysaccharide and the O-specific antigen impede antibody binding: a potential obstacle for the successful development of an extraintestinal pathogenic Escherichia coli vaccine

Extraintestinal pathogenic Escherichia coli (ExPEC) cause a wide variety of infections that are responsible for significant morbidity, mortality and costs to our healthcare system. An efficacious vaccine against ExPEC would be desirable. Previously, we demonstrated that nasal immunization with a genetically engineered strain in which capsule and O-antigen are no longer expressed (CP923) was immunogenic, generated antibodies that bound a subset of heterologous ExPEC strains, and enhanced neutrophil-mediated bactericidal activity against the homologous and a heterologous strain in vitro. In the work reported here we tested the hypothesis that nasal immunization with CP923 conferred protection in a mouse intravenous sepsis model. Nasal immunization with the wild-type strain CP9 conferred protection against challenge with itself and this protection was enhanced when IL-12 was used as an adjuvant. However, when CP923 was used the immunogen, protection was not observed against challenge with CP9. Next, we hypothesized that the observed lack of protection may be due to capsule and the O-antigen moiety of lipopolysaccharide (LPS) impeding antibody binding to non-capsule and O-antigen epitopes. This hypothesis was substantiated by in vitro binding assays, which demonstrated that binding of polyclonal anti-CP923 antisera was decreased when capsule and/or O-antigen were present. Lastly, neutrophil-mediated bactericidal activity against CP923, opsonisized with anti-CP923 antisera, was significantly increased compared to CP9. Taken together, these results demonstrate that the capsule and O-antigen form a biologically significant barrier against antibodies directed against non-capsular and O-antigen epitopes. This defense against the acquired immune response will need to be overcome for the development of a successful vaccine against ExPEC.

The metagenomics RAST server - a public resource for the automatic phylogenetic and functional analysis of metagenomes

Background

Random community genomes (metagenomes) are now commonly used to study microbes in different environments. Over the past few years, the major challenge associated with metagenomics shifted from generating to analyzing sequences. High-throughput, low-cost next-generation sequencing has provided access to metagenomics to a wide range of researchers.

Results

A high-throughput pipeline has been constructed to provide high-performance computing to all researchers interested in using metagenomics. The pipeline produces automated functional assignments of sequences in the metagenome by comparing both protein and nucleotide databases. Phylogenetic and functional summaries of the metagenomes are generated, and tools for comparative metagenomics are incorporated into the standard views. User access is controlled to ensure data privacy, but the collaborative environment underpinning the service provides a framework for sharing datasets between multiple users. In the metagenomics RAST, all users retain full control of their data, and everything is available for download in a variety of formats.

Conclusion

The open-source metagenomics RAST service provides a new paradigm for the annotation and analysis of metagenomes. With built-in support for multiple data sources and a back end that houses abstract data types, the metagenomics RAST is stable, extensible, and freely available to all researchers. This service has removed one of the primary bottlenecks in metagenome sequence analysis – the availability of high-performance computing for annotating the data.

Capsule and O-antigen from an extraintestinal isolate of Escherichia coli modulate cytokine levels in rat macrophages in vitro and in a rat model of pneumonia

Gram-negative pneumonia results in significant morbidity, mortality, and cost to the healthcare system. Previously the authors demonstrated that capsule and O-antigen, virulence factors of the extraintestinal Escherichia coli isolate CP9, modulate pulmonary neutrophil influx in a rat pneumonia model. In this report, the authors utilized CP9 and mutants deficient in O-antigen (CP921), capsule (CP9.137), or both (CP923) to test the hypothesis that modulation of cytokine levels by capsule and/or O-antigen may be a contributory mechanism. Effects of capsule and O-antigen on cytokine levels in rats in vivo and in isolated pulmonary macrophages in vitro were assessed. In vivo, capsule and O-antigen had no significant effect on tumor necrosis factor (TNF)-alpha levels in bronchoalveolar lavage fluid (BALF), but both were associated with significant increases in the levels of interleukin (IL)-1beta and Cytokine-induced neutrophil Chemoattractant-1 (CINC-1). However, potential difficulties in interpreting data occurred because challenge bacterial strains exhibited differential growth, and clearance characteristics and mixed cell populations were present. Therefore, added mechanistic studies investigated specific interactions of capsule and O-antigen with pulmonary macrophages purified from normal rats and exposed to CP9, CP921, CP9.137, or CP923 in vitro. Results indicated that the presence of capsule led to significantly increased levels of TNF-alpha, IL-1beta, and CINC-1, whereas O-antigen significantly decreased macrophage-associated levels of these mediators. These findings support the hypothesis that CP9 capsule is proinflammatory for macrophage-induced neutrophil recruitment, whereas O-antigen attenuates macrophage production of proinflammatory mediators in pneumonia. These results expand our understanding on the mechanisms by which these virulence traits may contribute to the inflammatory pathogenesis of pneumonia.

A killed, genetically engineered derivative of a wild-type extraintestinal pathogenic E. coli strain is a vaccine candidate

Infections due to extraintestinal pathogenic E. coli (ExPEC) result in significant morbidity, mortality and increased healthcare costs. An efficacious vaccine against ExPEC would be desirable. In this report, we explore the use of killed-whole E. coli as a vaccine immunogen. Given the diversity of capsule and O-antigens in ExPEC, we have hypothesized that alternative targets are viable vaccine candidates. We have also hypothesized that immunization with a genetically engineered strain that is deficient in the capsule and O-antigen will generate a greater immune response against antigens other than the capsular and O-antigen epitopes than a wild-type strain. Lastly, we hypothesize that mucosal immunization with killed E. coli has the potential to generate a significant immune response. In this study, we demonstrated that nasal immunization with a formalin-killed ExPEC derivative deficient in capsule and O-antigen results in a significantly greater overall humoral response compared to its wild-type derivative (which demonstrates that capsule and/or the O-antigen impede the development of an optimal humoral immune response) and a significantly greater immune response against non-capsular and O-antigen epitopes. These antibodies also bound to a subset of heterologous ExPEC strains and enhanced neutrophil-mediated bactericidal activity against the homologous and a heterologous strain. Taken together, these studies support the concept that formalin-killed genetically engineered ExPEC derivatives are whole cell vaccine candidates to prevent infections due to ExPEC.

Surfactant dysfunction and lung injury due to the E. coli virulence factor hemolysin in a rat pneumonia model

This study tests the hypothesis that the virulence factor hemolysin (Hly) expressed by extraintestinal pathogenic Escherichia coli contributes to surfactant dysfunction and lung injury in a rat model of gram-negative pneumonia. Rats were instilled intratracheally with CP9 (wild type, Hly-positive), CP9hlyA (Hly-minus), CP9/pEK50 (supraphysiological Hly), or purified LPS. At 6 h postinfection, rats given CP9 had a decreased percentage content of large surfactant aggregates in cell-free bronchoalveolar lavage (BAL), decreased large aggregate surface activity, decreased Pa(O2)/FiO2) ratio, increased BAL albumin/protein levels, and increased histological evidence of lung injury compared with rats given CP9hlyA or LPS. In addition, rats given CP9/pEK50 or CP9 had decreased large aggregate surface activity, decreased Pa(O2)/FiO2) ratios, and increased BAL albumin/protein levels at 2 h postinfection compared with rats given CP9hlyA. The severity of permeability lung injury based on albumin/protein levels in BAL at 2 h was ordered as CP9/pEK50 > CP9 > CP9hlyA > normal saline controls. Total lung titers of bacteria were increased at 6 h in rats given CP9 vs. CP9hlyA, but bacterial titers were not significantly different at 2 h, indicating that increased surfactant dysfunction and lung injury were associated with Hly as opposed to bacterial numbers per se. Further studies in vitro showed that CP9 could directly lyse transformed pulmonary epithelial cells (H441 cells) but that indirect lysis of H441 cells secondary to Hly-induced neutrophil lysis did not occur. Together, these data demonstrate that Hly is an important direct mediator of surfactant dysfunction and lung injury in gram-negative pneumonia.

E. colivirulence factor hemolysin induces neutrophil apoptosis and necrosis/lysis in vitro and necrosis/lysis and lung injury in a rat pneumonia model

Enteric gram-negative bacilli, such as Escherichia coli are the most common cause of nosocomial pneumonia. In this study a wild-type extraintestinal pathogenic strain of E. coli (ExPEC)(CP9) and isogenic derivatives deficient in hemolysin (Hly) and cytotoxic necrotizing factor (CNF) were assessed in vitro and in a rat model of gram-negative pneumonia to test the hypothesis that these virulence factors induce neutrophil apoptosis and/or necrosis/lysis. As ascertained by in vitro caspase-3/7 and LDH activities and neutrophil morphology, Hly mediated neutrophil apoptosis at lower E. coli titers (1 × 105–6cfu) and necrosis/lysis at higher titers (≥1 × 107cfu). Data suggest that CNF promotes apoptosis but not necrosis or lysis. We also demonstrate that annexin V/7-amino-actinomycin D staining was an unreliable assessment of apoptosis using live E. coli. The use of caspase-3/7 and LDH activities and neutrophil morphology supported the notion that necrosis, not apoptosis, was the primary mechanism by which neutrophils were affected in our in vivo gram-negative pneumonia model using live E. coli. In addition, in vivo studies demonstrated that Hly mediates lung injury. Neutrophil necrosis was not observed when animals were challenged with purified lipopolysaccharide, demonstrating the importance of using live bacteria. These findings establish that Hly contributes to ExPEC virulence by mediating neutrophil toxicity, with necrosis/lysis being the dominant effect of Hly on neutrophils in vivo and by lung injury. Whether Hly-mediated lung injury is due to neutrophil necrosis, a direct effect of Hly, or both is unclear.

The Siderophore receptor IroN of extraintestinal pathogenic Escherichia coli is a potential vaccine candidate

It would be medically and economically desirable to prevent the millions of annual extraintestinal infections and the thousands of associated deaths due to Escherichia coli. Outer membrane proteins are potential vaccine candidates for the prevention of these infections. This study tested the hypotheses that the siderophore receptor IroN is antigenic and that an IroN-specific antibody response confers protection in vivo. Subcutaneous immunization with denatured IroN resulted in a significant IroN immunoglobulin G (IgG)-specific response in serum (P < 0.0001) but not a systemic or mucosal IroN-specific IgA response. In a mouse model of ascending urinary tract infection, subcutaneous immunization with denatured IroN conferred significant protection against renal (P = 0.0135 and 0.0095 in two independent experiments), but not bladder, infection. These data, together with the previously demonstrated role of IroN in virulence, its expression in human biologic fluids, and its prevalence among extraintestinal pathogenic E. coli strains, support further studies on the role of IroN as a vaccine candidate.

Human neutrophil chemotaxis is modulated by capsule and O antigen from an extraintestinal pathogenic Escherichia coli strain

Gram-negative enteric bacilli, such as Escherichia coli, are common causes of nosocomial pneumonia. The interaction between pulmonary neutrophils and the infecting pathogen is a critical step in determining the outcome. Previous studies from our laboratory, for which a rat model of pneumonia was used, established that pulmonary neutrophil recruitment was modulated by the E. coli virulence factors capsule and O-specific antigen. To begin to understand the mechanism by which this recruitment occurs, we conducted in vitro and ex vivo chemotaxis assays, for which we used a clinically relevant E. coli isolate (CP9) and isogenic derivatives that were deficient in only the O antigen (CP921) or capsule (CP9.137) as chemoattractants with or without the high-affinity N-formylmethionyl-leucyl-phenylalanine receptor antagonist N-tert-butoxycarbonyl-methionine-leucine-phenylalanine (N-t-BOC). Given that only live E. coli was used for the initial in vitro chemotaxis assays, it was predicted that only N-t-BOC-sensitive chemotaxis would occur. However, both N-t-BOC-sensitive and -insensitive chemotaxis was observed. N-t-BOC-insensitive chemotaxis was mediated in part by interleukin 8, which was produced by neutrophils that had migrated toward E. coli. N-t-BOC-insensitive chemotaxis was only observed when live E. coli bacteria, not cell-free E. coli culture supernatants, were used as chemoattractants, suggesting that a direct E. coli-neutrophil interaction was necessary. The presence of both capsule and O antigen diminished total, N-t-BOC-sensitive, and N-t-BOC-insensitive neutrophil chemotaxis in vitro. The presence of capsule significantly decreased total, N-t-BOC-sensitive, and N-t-BOC-insensitive neutrophil chemotaxis ex vivo when cell-free bronchoalveolar lavage fluid from infected rats was used as the source of chemotactic factors. These effects of E. coli capsule and O antigen on neutrophil chemotaxis are novel, and they expand our understanding of the mechanisms by which these virulence traits contribute to the pathogenesis of gram-negative pneumonia and other extraintestinal infections.

The nematode Anisakis simplex in American shad (Alosa sapidissima) in two Oregon rivers

This paper represents the first report of the nematode Anisakis simplex in the American shad (Alosa sapidissima) in its introduced range in the American Pacific Northwest. All the adult shad sampled from spawning populations in the Willamette (n = 9) and Umpqua (n = 12) rivers were infected with A. simplex with intensities ranging from 6 to 89 worms per fish. This preliminary investigation contrasts sharply with previous studies in the native range of American shad and confirms that this fish may be an important intermediate host for A. simplex in the Pacific Northwest. It is suggested that this new parasite-host relationship has led to an ecological expansion into rivers and Anisakis may present an emerging health risk for wildlife and some human consumers.

HLA class II markers and clinical heterogeneity in Swedish patients with primary biliary cirrhosis

Genetic susceptibility to PBC can, at least in part, be ascribed to the major histocompatibility complex. The relevance of immunogenetic markers for the clinical presentation and course, however, is unclear. Thus, the aim of this study was to investigate the contribution of HLA class II genes to susceptibility, clinical presentation and course of disease in PBC patients. HLA genotyping for HLA-DRB1, -DQB1 and -DPB1 was carried out in a total of 99 Swedish PBC patients and 158 controls. Clinical parameters including epidemiologic variables, signs and symptoms of PBC-related liver disease and histologic data were collected and analyzed in 92 patients at study entry and at follow-up five years later. Significant clinical heterogeneity was seen among PBC patients upon study entry. Although a significant disease association was seen for HLA DRB1*08 and DQB1*0402, immunogenetic markers identified neither a particular subset of patients nor an association with the clinical course of the disease. HLA-DRB1*08 and DQB1*0402 provide the strongest immunogenetic influence in PBC. However, this association is not restricted to any particular, clinically defined subgroup of patients and it is not predictive for the course of the disease.

Mechanisms for ligand binding to GluR0 ion channels: crystal structures of the glutamate and serine complexes and a closed apo state

High-resolution structures of the ligand binding core of GluR0, a glutamate receptor ion channel from Synechocystis PCC 6803, have been solved by X-ray diffraction. The GluR0 structures reveal homology with bacterial periplasmic binding proteins and the rat GluR2 AMPA subtype neurotransmitter receptor. The ligand binding site is formed by a cleft between two globular alpha/beta domains. L-Glutamate binds in an extended conformation, similar to that observed for glutamine binding protein (GlnBP). However, the L-glutamate gamma-carboxyl group interacts exclusively with Asn51 in domain 1, different from the interactions of ligand with domain 2 residues observed for GluR2 and GlnBP. To address how neutral amino acids activate GluR0 gating we solved the structure of the binding site complex with L-serine. This revealed solvent molecules acting as surrogate ligand atoms, such that the serine OH group makes solvent-mediated hydrogen bonds with Asn51. The structure of a ligand-free, closed-cleft conformation revealed an extensive hydrogen bond network mediated by solvent molecules. Equilibrium centrifugation analysis revealed dimerization of the GluR0 ligand binding core with a dissociation constant of 0.8 microM. In the crystal, a symmetrical dimer involving residues in domain 1 occurs along a crystallographic 2-fold axis and suggests that tetrameric glutamate receptor ion channels are assembled from dimers of dimers. We propose that ligand-induced conformational changes cause the ion channel to open as a result of an increase in domain 2 separation relative to the dimer interface.

Changes in psychiatric diagnoses from admission to discharge: review of the charts of 159 patients consecutively admitted to a geriatric psychiatry inpatient unit

The diagnosis of psychopathology among geriatric acute inpatients requires comprehensive evaluation. To our knowledge, no recently published papers in the geriatric psychiatry literature have systematically examined diagnostic changes during single admissions. We reviewed the charts of 159 patients consecutively admitted to an acute geriatric psychiatry unit over 18 months. We recorded admission diagnoses from initial treatment plans, and discharge diagnoses from discharge summaries. Mean patient age was 80 years and average length of stay was 17 days. The most common primary diagnoses were psychotic and depressive disorders. The most common secondary diagnoses were dementias and depressive disorders. Primary diagnoses changed from admission to discharge in 31 patients (20%), and secondary diagnoses changed in 76 patients (48%). There was a significant change involving the diagnosis of dementia, but not that of depressive or psychotic disorders. A large proportion of inpatients had their diagnoses altered, especially those involving dementias, during hospitalization. Inpatient admission may be valuable for clarifying the diagnoses of elderly psychiatric patients.

Effect of 10%, 30%, and 60% body weight traction on the straight leg raise test of symptomatic patients with low back pain

STUDY DESIGN

Single group test-retest repeated measures.

OBJECTIVES

To determine the effects of lumbar traction with 3 different amounts of force (10%, 30% and 60% body weight) on pain-free mobility of the lower extremity as measured by the straight leg raise (SLR) test.

BACKGROUND

There are several recommendations on how lumbar traction should be performed, but the duration, frequency, force, and type of technique to be applied differ among the sources.

METHODS AND MEASURES

Ten subjects with subjective complaints of low back pain or radicular symptoms with a positive unilateral SLR test below 45 degrees participated in this study. The pain-free mobility of the lower extremity in the SLR test position was measured prior to and immediately following 5 minutes of static traction in the supine position. Random assignment in the order of the amount of applied traction was implemented.

RESULTS

The straight leg raise measurements were found to be significantly greater immediately following 30% and 60% of body weight traction as compared to pretraction and 10% of body weight traction. The mean (SD) SLR measurements were pretraction (24.1 degrees +/- 13.0), 10% of body weight traction (27.4 degrees +/- 14.5), 30% of body weight traction (34.0 degrees +/- 14.3), 60% of body weight traction (36.5 degrees +/- 15.8).

CONCLUSIONS

The results of this study indicate that traction in this group of patients improved the mobility of the lower extremity during the SLR test. Both 30% and 60% of body weight tractions were shown to be effective for increasing motion beyond pretraction levels.

Camp Can-Do. Outcomes of an experiential learning experience

Because the most effective way to learn is by doing, faculty need to develop experiential learning experiences for students. The authors discuss one such experience, a multiple sclerosis camp where nursing students lived with and cared for their clients for 6 days. The camp experience illustrates how educators can partner with community organizations to the benefit of both.

The effect of transferrin polymorphisms on iron metabolism

The effect of five different transferrin variants (TFv1, TFv2, TFv3, TFv4, and TFv5) on the hemoglobin level, mean corpuscular volume (MCV), ferritin level, percent transferrin saturation (%TS), and the unsaturated iron binding capacity (UIBC) was investigated in subjects with defined HFE haplotypes, 919 persons undergoing health screening and 113 patients with clinical hemochromatosis. The most common variant is TFv4; the population distribution of this variant was also studied. None of the variants were found to have an effect on any of the parameters of iron metabolism that were investigated. Moreover, the frequency of these variants in patients with clinically significant hemochromatosis was no different from that in the general population. We conclude that these polymorphisms in transferrin do not play a role in the expression of hemochromatosis, nor do they produce any other significant changes in iron metabolism.

Crystal structure of staphylococcal LukF delineates conformational changes accompanying formation of a transmembrane channel

Staphylococcal LukF, LukS, HgammaII, and alpha-hemolysin are self-assembling, channel-forming proteins related in sequence and function. In the alpha-hemolysin heptamer, the channel-forming beta-strands and the amino latch make long excursions from the protomer core. Here we report the crystal structure of the water soluble form of LukF. In the LukF structure the channel-forming region folds into an amphipathic, three-strand beta-sheet and the amino latch forms a beta-strand extending a central beta-sheet. The LukF structure illustrates how a channel-forming toxin masks protein-protein and protein-membrane interfaces prior to cell binding and assembly, and together with the alpha-hemolysin heptamer structure, they define the end points on the pathway of toxin assembly.

Stability of the MCMI-III in a substance-abusing inpatient sample

The stability of the MCMI-III personality disorder and clinical syndrome scales was assessed in a substance-abusing inpatient sample of 35 African-American men over an average test-retest interval of 6 mo. Estimates were higher for the personality pattern scales than for the clinical syndrome scales. The Dependent personality pattern scale (.83) and the Narcissistic personality pattern scale (.80) were reliable after about six months, whereas Drug Abuse, Somatoform, and Major Depression showed lower stability. As in previous research using the MCMI-I/II, estimates were lower than those reported in the test manual.

XV454, a novel nonpeptide small-molecule platelet GIIb/IIIa antagonist with comparable platelet alpha(IIb)beta3-binding kinetics to c7E3

XV454 demonstrated high potency (IC50 = 14-25 nM) in inhibiting human platelet aggregation induced by adenosine diphosphate (ADP, 10 microM), thrombin receptor agonist peptide (TRAP) (10 microM), or collagen (20 microg/ml). XV454 exhibited a high degree of selectivity for platelet alpha(IIb)beta3 in comparison with c7E3, which is a nonspecific antagonist for both alpha(IIb)beta3 and alpha(v)beta3. Both XV454 and c7E3 bind with high affinity to either activated (A) or unactivated (U) human, baboon, or canine platelets. XV454 binds with a relatively higher affinity [Kd = 0.5 nM (A), 0.6 nM (U)] as compared with c7E3 [Kd = 9.1 nM (A), 9.2 (U) nM]. XV454 demonstrated a tight association with human, baboon, and, to a lesser extent, with canine platelets (t(1/2) of dissociation = 110 +/- 6, 80 +/- 10, and 23 +/- 2 min, respectively). Both c7E3 and XV454 associate tightly with a slower dissociation rate with unactivated human platelets: t(1/2) of 42 and 116 min, respectively. In non-human primates, oral (0.1 mg/kg, p.o.) and intravenous (0.05 mg/kg, i.v. bolus administration of XV454 methyl ester pro-drug resulted a long-lasting maximal antiplatelet efficacy for < or = 72 h with significant but reversible prolongation of bleeding time and without effects on platelet count, clinical chemistry, or hemodynamic profile. In conclusion, XV454 represents a potent antiplatelet agent in inhibiting platelet aggregation along with a high affinity and relatively slow dissociation rate from human platelet GPIIb/IIIa receptors that allow a long-lasting antiplatelet efficacy after single i.v. or oral administration.

Treatment with either high or low frequency TENS reduces the secondary hyperalgesia observed after injection of kaolin and carrageenan into the knee joint

For years, physical therapists have been utilizing a variety of modalities, including transcutaneous electrical nerve stimulation (TENS), in an attempt to manage pain associated with inflammation. However, the data on clinical effectiveness is conflicting and the neurophysiological mechanism of action is not known. The purpose of this study was to investigate the effects of high and low frequency TENS on the secondary hyperalgesia that occurs after joint inflammation. Secondary hyperalgesia is thought to reflect changes in central neurons and is thus a measure of activity of central neurons. This study utilized the kaolin and carrageenan model of knee joint inflammation and measured the effects of TENS treatment on paw withdrawal latency to radiant heat (secondary hyperalgesia), spontaneous pain behaviors and joint circumference. Either high (100 Hz) or low (4 Hz) frequency TENS was applied to the knee joint for 20 min after the development of hyperalgesia. Both high and low frequency TENS resulted in a reversal of the hyperalgesia immediately following treatment. The effects of high frequency TENS lasted through at least 24 h while those of low frequency TENS lasted through 12 h. There was no effect of TENS on spontaneous pain behaviors or joint swelling when compared to controls. Thus, TENS appears to be more effective in reducing referred pain (or secondary hyperalgesia) without affecting guarding or splinting of the affected limb. Thus, clinically, the choice to use TENS may depend on patient symptoms; specifically TENS should be effective in reducing referred or radiating pain.