Antagonism between co-infecting gastrointestinal nematodes: A meta-analysis of experimental infections in Sheep

Gastrointestinal nematodes (GIN) have enormous global impacts in humans, wildlife and grazing livestock. Within grazing livestock, sheep are of particular global importance and the economics and sustainability of sheep production are greatly constrained by GIN infections. Natural infections are composed of co-infections with multiple species, and while some past work suggests species can interact negatively with one another within the same host, there is wide variation in reported patterns. Here, we undertook a systematic literature search and meta-analysis of experimental GIN co-infections of sheep to determine whether these experimental studies support the hypothesis of antagonistic interactions between different co-infecting GIN, and test whether aspects of parasite biology or experimental design influence the observed effects. A systematic search of the literature yielded 4848 studies, within which, we identified 19 experimental sheep studies comparing post-mortem worm counts across two co-infecting GIN species. Meta-analysis of 67 effects obtained from these studies provides strong evidence for interactions between GIN species. There was wide variation in the strength and direction of these interactions, but the global effect was significantly antagonistic. On average, there was a decrease in the number of worms of one species when a co-infecting species was also present, relative to a mono-infection with that species alone. This effect was dependent on the infectious dose and was rapidly lost after anthelmintic treatment, suggesting that live worms are required for the effect to occur. Individual parasite species varied in the extent to which they both exerted, and were subject to, these interspecies interactions, and these differences are more complex than simply co-localisation within the gastrointestinal tract. Antagonistic interactions between co-infecting GIN may feedback into their epidemiology as well as potentially affecting the clinical impacts of infection. Furthermore, the consequences of these interactions may be heightened when clinical interventions affect only one species within the co-infecting network. Whilst it was not possible to identify the causes of variation between GIN species in the impact of co-infection, these findings point to new avenues for epidemiological, clinical and mechanistic research on GIN co-infections.

Temporal trends in reptile occurrence among temperate old-growth, regrowth and replanted woodlands

Reptiles are an important part of the vertebrate fauna in the temperate woodlands of south-eastern Australia. However, compared to birds and mammals, the long-term occurrence of reptiles across woodland growth types-old growth, regrowth, and replantings-remains poorly understood. Here, using 18-years of data gathered at 218 sites across 1.5 million hectares in New South Wales South West Slopes bioregion, we sought to quantify patterns of temporal change in reptile occurrence and determine if such changes varied between woodland growth types. Despite extensive sampling, almost 75% of our 6341 surveys produced no detections of reptiles. Significant survey effort exceeding 2000 surveys was needed over a prolonged period of time to record detections of 26 reptile species in our study area. Our analyses showed a temporal increase in estimated reptile species richness and abundance over 18 years. Such increases characterized all three vegetation structural types we surveyed. At the individual species level, we had sufficient data to construct models for five of the 26 species recorded. Three of these species were least commonly detected in replantings, whereas the remaining two were most often detected in replantings relative to old growth and regrowth woodland. We found evidence of a temporal increase in two skink species, a decline in one gecko species, and no change in the remaining two skink species. Although detections were consistently low, active searches were the best survey method, and we suggest using this method in habitats known to be hotspots for reptiles, such as rocky outcrops, if the aim is to maximize the number of individuals and species detected. Our findings highlight the value of all three broad vegetation structure types in contributing to woodland reptile biodiversity.

Free-roaming dog population dynamics in Ranchi, India

Rabies causes approximately 20,000 human deaths in India each year. Nearly all of these occur following dog bites. Large-scale, high-coverage dog rabies vaccination campaigns are the cornerstone of rabies elimination strategies in both human and dog populations, although this is particularly challenging to achieve in India as a large proportion of the dog population are free-roaming and unowned. Further, little is known about free-roaming dog ecology in India which makes defining optimum vaccination strategies difficult. In this study, data collected using a mobile phone application during three annual mass vaccination and neutering (surgical sterilisation of both males and females) campaigns of free-roaming dogs in Ranchi, India (during which a total of 43,847 vaccinations, 26,213 neuter surgeries and 28,172 re-sight observations were made) were interrogated, using two novel approaches to estimate the proportion of neutered dogs that were lost from the city (assumed due to mortality or migration) between campaign years. Analysis revealed high losses of neutered dogs each year, ranging from 25.3% (28.2-22.8) to 55.8% (57.0-54.6). We also estimated that the total population declined by 12.58% (9.89-15.03) over the three-year period. This demonstrates that there is a high turnover of free-roaming dogs and that despite neutering a large number of dogs in an annual sterilisation campaign, the decline in population size was modest over a three-year time period. These findings have significant implications for the planning of rabies vaccination campaigns and population management programmes as well as highlighting the need for further research into the demographics of free-roaming, unowned dogs in India.

Maternity Healthcare Chaplains and Perinatal Post-Mortem Support and Understanding in the United Kingdom and Ireland: An Exploratory Study

Perinatal autopsy rates have declined significantly in recent decades. There is a lack of consensus concerning the potential religious influences for bereaved parents in their decision making process for post-mortem. This online study of British and Irish maternity healthcare chaplains explored their understanding of general and local perinatal post-mortem procedures and their experiences in the support of parents. Participants included Christian, Muslim and non-faith chaplains. No chaplain identified any religious prohibition to perinatal post-mortem. A majority of chaplains reported that they had been asked about post-mortem by parents; only a minority felt adequately prepared. A key recommendation is that following appropriate training chaplains may be well placed to support colleagues and parents during the decision making process.

A 4 year observation of gastrointestinal nematode egg counts, nemabiomes and the benzimidazole resistance genotypes of Teladorsagia circumcincta on a Scottish sheep farm

Anthelmintic resistance threatens the sustainability of sheep production globally. Advice regarding strategies to reduce the development of anthelmintic resistance incorporates the outcomes of modelling exercises. Further understanding of gastrointestinal nematode species diversity, and population dynamics and genetics (which may vary between species) is required to refine these models; and field studies combining faecal egg outputs, species composition and resistance genetics are needed to calibrate them. In this study, faecal samples were taken from ewes and lambs on a commercial farm in south-eastern Scotland at approximately 3 t-4 week intervals between spring and autumn over a period of 4 years. Faecal egg counts were performed on these samples, and L₃ were collected from pooled coprocultures. Deep amplicon sequencing was used to determine both the species composition of these L₃ and the proportions of benzimidazole-resistant single nucleotide polymorphisms in the isotype-1 β-tubulin locus of the predominant species, Teladorsagia circumcincta L₃. Despite consistent management throughout the study, the results show variation in gastrointestinal nematode species composition with time and between age groups, that was potentially associated with weather conditions. The F200Y benzimidazole resistance mutation is close to genetic fixation in the T. circumcincta population on this farm. There was no evidence of variation in isotype-1 β-tubulin single nucleotide polymorphisms frequency between age groups, and no genetic evidence of reversion to benzimidazole susceptibility, despite targeted benzimidazole usage. This study highlights the need to include speciation when investigating gastrointestinal nematode epidemiology and anthelmintic resistance, and serves as an example of how genetic data may be analysed alongside species diversity and faecal egg counts, when markers for other anthelmintic classes are identified.

Pollination and resource limitation as interacting constraints on almond fruit set

Pollination and resource availability are factors determining reproductive success of plants, and in agriculture these factors influence yield of fruit-bearing crops. Our understanding of the importance of crop pollination is fast improving, but less is known about how the interaction between pollination and resources constrains fruit production. We conducted an experiment with almond trees (Prunus dulcis) to examine how the number of flowers, light availability and competition for resources affected nut (fruit) production on individual spurs (fruit-bearing structures) exposed to open-pollination or hand-pollination. We found a positive relationship between flower number and nut number on spurs with up to four flowers, but no further benefit after four flowers, suggesting a resource threshold expressed by individual spurs. Spurs with few flowers increased the conversion rate of flowers to nuts when supplemented with hand-pollination, but spurs with more flowers were more likely to achieve the threshold number of nuts even under open-pollination. Our experiment included a further treatment involving spraying whole trees with pollen. This treatment reduced nut production by spurs with many flowers and high light availability, suggesting competition is experienced by well-resourced spurs when resources need to be shared among developing nuts across the whole tree. Our study supports the hypothesis that excess flower production in fruit trees increases the potential for fruit production when pollinator and resource availability is variable (bet-hedging). Spurs with more flowers typically produce more nuts (within a limited range), but only if both resources and pollen supply increase with flower number. For almond growers, a focus on maintaining high flower numbers, especially in high light regions of the canopy, is the foundation for high levels of production. Strategies to lift flower number and light are complicated by trade-offs inherent in tree architecture and orchard design. However, fruit set would be lifted above that achieved by current practice by an increase in the pollination rate of flowers.

Effects of halogens on European air-quality

Halogens (Cl, Br) have a profound influence on stratospheric ozone (O₃). They (Cl, Br and I) have recently also been shown to impact the troposphere, notably by reducing the mixing ratios of O₃ and OH. Their potential for impacting regional air-quality is less well understood. We explore the impact of halogens on regional pollutants (focussing on O₃) with the European grid of the GEOS-Chem model (0.25° × 0.3125°). It has recently been updated to include a representation of halogen chemistry. We focus on the summer of 2015 during the ICOZA campaign at the Weybourne Atmospheric Observatory on the North Sea coast of the UK. Comparisons between these observations together with those from the UK air-quality network show that the model has some skill in representing the mixing ratios/concentration of pollutants during this period. Although the model has some success in simulating the Weybourne ClNO₂ observations, it significantly underestimates ClNO₂ observations reported at inland locations. It also underestimates mixing ratios of IO, OIO, I₂ and BrO, but this may reflect the coastal nature of these observations. Model simulations, with and without halogens, highlight the processes by which halogens can impact O₃. Throughout the domain O₃ mixing ratios are reduced by halogens. In northern Europe this is due to a change in the background O₃ advected into the region, whereas in southern Europe this is due to local chemistry driven by Mediterranean emissions. The proportion of hourly O₃ above 50 nmol mol^-1 in Europe is reduced from 46% to 18% by halogens. ClNO₂ from N₂O₅ uptake onto sea-salt leads to increases in O₃ mixing ratio, but these are smaller than the decreases caused by the bromine and iodine. 12% of ethane and 16% of acetone within the boundary layer is oxidised by Cl. Aerosol response to halogens is complex with small (∼10%) reductions in PM_2.5 in most locations. A lack of observational constraints coupled to large uncertainties in emissions and chemical processing of halogens make these conclusions tentative at best. However, the results here point to the potential for halogen chemistry to influence air quality policy in Europe and other parts of the world.

Fetal Dysmorphology-Still an Essential Art. Analysis of the Limitations of Microarray in a Fetal Population and a Look Toward the Genome Sequencing Era

Cytogenomic microarray allows assessment of the genome at higher resolutions than traditional karyotyping. The objective of this study is to evaluate the utility of microarray in a routine fetal autopsy setting before the advent of routine fetal exome/genome sequencing and the issues these technologies may generate. A systematic review of fetal postmortems at 12-24 weeks gestation between January 2011 and December 2014 was undertaken. Cases where there was no consent for audit, research, or genetic testing were excluded as were cases referred to the Procurator Fiscal, stillbirths, and neonatal deaths. Copy number variations were detected in 16 cases. In addition, there was 1 case of uniparental disomy; not all of these were related to the phenotype. There were a number of cases with phenotypic abnormalities and normal array results. Five of these underwent directed mutation analysis-3 were positive. Genetic laboratory investigations such as microarray and Quantitative Fluorescent-Polymerase Chain Reaction may increase the diagnostic yield in the assessment of fetal dysmorphology. However, this study shows that genetic results not only require careful review given the potential uncertain significance but also require phenotypic assessment of the fetus by a competent fetal dysmorphologist to determine the likely causative effect of any detected anomaly. This best practice will also extend to next generation sequencing and interpretation of variants of unknown significance. Fetal medicine teams should ideally include specialists well versed in assessment of fetal anomaly to provide families with the best possible information about the cause of their pregnancy loss and their options for future pregnancies.

Lung effects of inhaled corticosteroids in a rhesus monkey model of childhood asthma

BACKGROUND

The risks for infants and young children receiving inhaled corticosteroid (ICS) therapy are largely unknown. Recent clinical studies indicate that ICS therapy in pre-school children with symptoms of asthma result in decreased symptoms without influencing the clinical disease course, but potentially affect postnatal growth and development. The current study employs a primate experimental model to identify the risks posed by ICS therapy.

OBJECTIVE

To (1) establish whether ICS therapy in developing primate lungs reverses pulmonary pathobiology associated with allergic airway disease (AAD) and (2) define the impact of ICS on postnatal lung growth and development in primates.

METHODS

Infant rhesus monkeys were exposed, from 1 through 6 months, to filtered air (FA) with house dust mite allergen and ozone using a protocol that produces AAD (AAD monkeys), or to FA alone (Control monkeys). From three through 6 months, the monkeys were treated daily with ICS (budesonide) or saline.

RESULTS

Several AAD manifestations (airflow restrictions, lavage eosinophilia, basement membrane zone thickening, epithelial mucin composition) were reduced with ICS treatment, without adverse effects on body growth or adrenal function; however, airway branching abnormalities and intraepithelial innervation were not reduced. In addition, several indicators of postnatal lung growth and differentiation: vital capacity, inspiratory capacity, compliance, non-parenchymal lung volume and alveolarization, were increased in both AAD and Control monkeys that received ICS treatment.

CONCLUSIONS AND CLINICAL RELEVANCE

Incomplete prevention of pathobiological changes in the airways and disruption of postnatal growth and differentiation of airways and lung parenchyma in response to ICS pose risks for developing primate lungs. These responses also represent two mechanisms that could compromise ICS therapy's ability to alter clinical disease course in young children.

The atmospheric chemistry of trace gases and particulate matter emitted by different land uses in Borneo

We report measurements of atmospheric composition over a tropical rainforest and over a nearby oil palm plantation in Sabah, Borneo. The primary vegetation in each of the two landscapes emits very different amounts and kinds of volatile organic compounds (VOCs), resulting in distinctive VOC fingerprints in the atmospheric boundary layer for both landscapes. VOCs over the Borneo rainforest are dominated by isoprene and its oxidation products, with a significant additional contribution from monoterpenes. Rather than consuming the main atmospheric oxidant, OH, these high concentrations of VOCs appear to maintain OH, as has been observed previously over Amazonia. The boundary-layer characteristics and mixing ratios of VOCs observed over the Borneo rainforest are different to those measured previously over Amazonia. Compared with the Bornean rainforest, air over the oil palm plantation contains much more isoprene, monoterpenes are relatively less important, and the flower scent, estragole, is prominent. Concentrations of nitrogen oxides are greater above the agro-industrial oil palm landscape than over the rainforest, and this leads to changes in some secondary pollutant mixing ratios (but not, currently, differences in ozone). Secondary organic aerosol over both landscapes shows a significant contribution from isoprene. Primary biological aerosol dominates the super-micrometre aerosol over the rainforest and is likely to be sensitive to land-use change, since the fungal source of the bioaerosol is closely linked to above-ground biodiversity.

Synergistic effects of osteonectin and brain-derived neurotrophic factor on axotomized retinal ganglion cells neurite outgrowth via the mitogen-activated protein kinase-extracellular signal-regulated kinase 1/2 pathways

Our previous study identified osteonectin (ON) in a screen of factors made by Schwann cells (SCs) which promoted peripheral and central neurons survival and neuritogenesis, however, the mechanisms of ON promoting effects are largely unknown. In the present study, we investigated the effects of ON-deficient SC-conditioned medium (SCCM) and molecular mechanisms of ON, in regulating retinal ganglion cells (RGCs) survival and neurite outgrowth. Neonatal rat RGCs and SCs were purified by immunopanning technique. RGC survival and neuritogenesis reduced significantly when treated with either ON-null mice SCCM or ON-immunodepleted (IP) SCCM (P<0.05). In contrast to wild type SCCM, in the presence of a tyrosine kinase receptor (Trk) inhibitor (K252a), ON-null mice SCCM-induced neuritogenesis were further reduced by 24%. The Trk-mediated signaling pathways became more sensitive to K252a inhibition in the absence of ON. We also showed the synergistic effects of ON and brain-derived neurotrophic factor (BDNF) in promoting RGCs growth and the involvement of ON in two major neurotrophin-mediated signaling pathways, PI-3K-Akt and MAPK-Erk1/2. ON alone activated Akt phosphorylation and increased survival. Blockage of TrkB signalling pathway by TrkB-Fc chimera (BDNF scavenger) or K252a in ON-treated cultures reduced Akt-P level significantly. This suggests that ON induces BDNF synthesis and secretion from RGCs. The enhancement of neuritogenesis and Erk1/2 phosphorylation by ON in BDNF-treated cultures further demonstrate the signaling pathways responsible for the synergistic effect of ON on BDNF-induced neurite outgrowth. To the best of our knowledge, this is the first report showing the synergistic effects of ON on classical neurotrophins which participate in the same signalling pathways in regulating RGC neurite outgrowth.

A hematopoietic stromal lesion associated with fractionated radiotherapy (FxRT): time- and dose-effects

Earlier, we reported that the local exposure of femoral bone marrow to a clinically-relevant course of fractionated radiotherapy [FxRT; 2.0 Gy (q24h x 5) --> 74 Gy] resulted in the delayed appearance of a stromal lesion which temporally appeared after exposures to a threshold dose of 20 Gy FxRT. To further define this threshold dose, the temporal recovery of blood-forming elements ("cobblestone area" forming colonies; CAFC(7-28d)) and the microenvironmental stroma (long-term bone marrow cultures; LTBMC) of the marrow was examined over a 17-week period following 10 and 30 Gy FxRT. After a subthreshold dose of 10 Gy, each of the 4 CAFC subpopulations were significantly dampened, with recovery initiated within a 6-week interval of 10 Gy of FxRT. Above the threshold dose (30 Gy FxRT), the CAFC subpopulations were again reduced to a level similar to that observed with 10 Gy FxRT. However, after exposures to 30 Gy FxRT, CAFC recovery was significantly well beyond the 6-week interval observed with a 10 Gy Dose of FxRT. Similarly, cell production in LTBMC prepared from marrow exposed to either 10 or 30 Gy FxRT was significantly dampened for at least 3 weeks following the FxRT. Moreover, while cell production in LTBMC derived from marrow exposed to 10 Gy was eventually restored to normal, the dampened cell production observed in LTBMC prepared after 30 Gy FxRT persisted for a period in excess of 17 weeks. Collectively, these observations provide additional support to our earlier observation suggesting that FxRT generates two forms of dose-dependent damage in the marrow: the first an early lesion arising in the blood-forming CAFC subpopulations; the second form, a delayed lesion that involves the persistent expression of a dysfunctional microenvironmental phenotype, appearing to disrupt the normal regulation of hematopoietic stem cell (HSC) proliferation and differentiation of the HSC during the recovery process.

Advice given in community pharmacies to patients with possible oral carcinoma

We compared advice given by community pharmacy staff in Worcestershire to a proxy consulter on behalf of a patient with a longstanding oral ulcer, presumed to be an oral cancer. If patients seek advice in this way the quality of the advice given is dependent on whether the respondent is a pharmacist or a community pharmacy assistant.

Smooth muscle hypertrophy in distal airways of sensitized infant rhesus monkeys exposed to house dust mite allergen

BACKGROUND

Airway smooth muscle hypertrophy is closely associated with the pathophysiology of hyper-reactive airways in allergic asthma.

OBJECTIVE

To determine whether repeated exposure to allergens during postnatal lung development promotes remodelling of airway smooth muscle.

METHODS

Infant, male rhesus monkeys (30-day-old) were sensitized to house dust mite allergen (HDMA) and then exposed to HDMA aerosol periodically over 5 months. Smooth muscle mass and bundle size and abundance in conducting airways were measured and compared with age-matched control (filtered air-exposed) monkeys.

RESULTS

Total smooth muscle mass and average bundle size were significantly greater in the conducting airways of monkeys exposed to HDMA. Smooth muscle bundle abundance was not affected by exposure to HDMA.

CONCLUSION

Repeated cycles of allergen exposure alter postnatal morphogenesis of smooth muscle, affecting both total mass and bundle size, in conducting airways of infant monkeys.

The use of the laryngeal mask in surgical tracheostomy

The laryngeal mask may be used as an airway during surgical tracheostomy. This techniques has several advantages over conventional oral endotracheal intubation.

Inter-relationships between the secretory dynamics of thyrotrophin-releasing hormone, thyrotrophin and prolactin in periovulatory mares: effect of hypothyroidism

We used our nonsurgical technique for collecting pituitary venous blood to relate the dynamics of thyrotrophin-releasing hormone (TRH) secretion to the secretion patterns of both prolactin and thyrotrophin in periovulatory mares, either euthyroid (n = 5) or made hypothyroid by treatment with propyl-thiouracil (n = 5). Pituitary venous blood was collected continuously and divided into 1-min aliquots for 4 h. To test the effect of dopamine on the relationship between secretion patterns, sulpiride, a selective D2 receptor antagonist, was given i.m. after 2 h of sampling. Thorough testing of the model and blood collection procedure revealed no sites of TRH loss. Hypothyroidism increased the mean secretion rates of TRH (P = 0.04) and thyrotrophin (P < 0.0001) but not prolactin. Sulpiride increased prolactin secretion rates in hypothyroid (P < 0.0001) and control (P = 0.007) mares, but did not alter TRH or thyrotrophin secretion rates. In both groups of mares, all three hormones were secreted episodically but not rhythmically. In both groups, the secretion pattern of TRH was almost always significantly related to that of thyrotrophin, as assessed by cross correlation and cross approximate entropy (ApEn) analysis. However, the degree of linear correlation was weak, with only 14% (hypothyroid) or 8% (controls) of the variation in thyrotrophin secretion rates attributable to TRH. Prolactin and TRH secretion patterns before sulpiride were coupled on cross ApEn analysis in both groups, and the minute-to-minute secretion rates of the two hormones were correlated in four hypothyroid and three euthyroid mares. Overall, the small, but significant, degree of association between TRH and prolactin was similar to that between TRH and thyrotrophin. In hypothyroid mares, sulpiride increased (P = 0.02) the synchrony between TRH and prolactin patterns. We conclude that in horses: (i) little TRH degradation occurs during passage through the pituitary or in blood after 1 h at 37 degrees C; (ii) TRH is not the major factor controlling minute-to-minute fluctuations in either thyrotrophin or prolactin; and (iii) reducing two strongly inhibitory inputs (i.e. dopamine and thyroid hormones) may magnify the stimulatory effect of TRH on prolactin secretion.

The remodelled tracheal basement membrane zone of infant rhesus monkeys after 6 months of recovery

BACKGROUND

In previous studies, we showed that repeated exposure to (1) house dust mite allergen (HDMA) (Dermatophagoides farinae) caused thickening of the basement membrane zone (BMZ) and (2) HDMA+ozone (O3) caused depletion of BMZ perlecan and atypical development of BMZ collagen (irregular thin areas<2.0 microm in width).

OBJECTIVE

The purpose of this study was to determine if these remodelling changes were reversible after 6 months of recovery.

METHODS

Rhesus monkeys were exposed to a regimen of HDMA and or O3 or filtered air (FA) for 6 months. After the exposure protocol was completed FA and O3 groups were allowed to recover in FA for 6 months. The HDMA and HDMA+O3 exposure groups recovered in a modified environment. They were re-exposed to HDMA aerosol for 2 h at monthly intervals during recovery in order to maintain sensitization for pulmonary function testing. To detect structural changes in the BMZ, collagen I and perlecan immunoreactivity were measured and compared to data from the previous papers.

RESULTS

The remodelled HDMA group had a significantly thicker BMZ and after 6 months of recovery the width had not regressed. In the remodelled BMZ of the HDMA+O3 group, perlecan had returned to the BMZ after 6 months of the recovery protocol, and the thin, irregular, collagen BMZ had been resolved.

CONCLUSION

In summary, this study has shown that: (1) The width of the remodelled HDMA BMZ did not regress during a recovery protocol that included a sensitizing dose of HDMA. (2) The atypical collagen BMZ in the HDMA+O3 BMZ was resolved in the absence of O3. (3) Depletion of perlecan from the BMZ by O3 was reversed by recovery in the absence of O3.

Immune and airway effects of house dust mite aeroallergen exposures during postnatal development of the infant rhesus monkey

BACKGROUND

The effect of chronic environmental aeroallergen exposure on the immune system and airways has not been experimentally defined in very young children.

OBJECTIVE

The purpose of this study was to determine the immunophenotype of peripheral blood and airway leucocytes in the newborn rhesus macaque monkey, following recurrent aerosol exposure to house dust mite (HDM) (Dermatophagoides farinae).

METHODS

A regimen of HDM aerosolization was initiated for 2 h per day, three times per week, starting when rhesus macaque monkeys were 1 week of age. All monkeys were inoculated with diptheria, tetanus, and acellular pertussis vaccine at 5 weeks of age to simulate human infant vaccination schedules.

RESULTS

Following 8 weeks of HDM aeroallergen exposure, infant monkeys exhibited a significant reduction in the total peripheral blood lymphocyte numbers and a decreased frequency of peripheral blood CD4+ T lymphocytes with a CD45RA-'memory' immunophenotype. Lavage CD4+ T lymphocytes from HDM-exposed monkeys showed elevated expression of CD25, as well as an increase in CD45RA-/CD62L-/CD11ahigh immunophenotype. Eosinophils were more abundant within airways of HDM-exposed monkeys, accumulating maximally within the trachea.

CONCLUSION

These data demonstrate the development of immunological responses following chronic inhalation of a common environmental allergen during postnatal maturation in the non-human primate.

Obliterative enteritis complicating graft versus host disease

We report a 10-year-old male with Down's syndrome, who received a bone marrow transplant for acute lymphoblastic leukaemia. Subsequent acute graft-versus-host disease (GvHD) of the gut progressed to small bowel obstruction. At laparotomy, the small bowel appeared solid and contracted with no or minimal luminal patency. Although the caecum had a lumen, it was indistensible, and it was not possible to enter the terminal ileum. Histology of the obstructed bowel showed extensive necrosis of the mucosa, muscularis mucosa and submucosa of most of the small bowel wall, causing obliteration of the lumen. The changes were presumed to be related to post inflammatory atrophy. This extreme manifestation of GvHD could thus be called obliterative enteritis. Both cytomegalovirus and adenovirus were isolated from the patient. These viruses may have contributed to the severity of the intestinal GvHD.

Cytokine profiles in patients receiving wide-field + prostate boost radiotherapy (xRT) for adenocarcinoma of the prostate

As a result of the association between ionizing irradiation and the induction of inflammatory and fibrogenic cytokines, circulating levels of IL-1alpha, macrophage colony stimulating factor (M-CSF) and TGFbeta were measured in a group of 37 patients who presented with well-defined adenocarcinoma of the prostate and were treated with wide-field pelvic (WFP) + prostate boost (PB) radiotherapy (xRT) according to RTOG protocols 94-08 and 94-13. First and foremost, patients with prostate cancer (PC) were found to have a significantly (p<0.05) elevated plasma level of the three cytokines prior to treatment. Moreover, during WFP + PB xRT, these circulating cytokine levels were further elevated, the elevation occurring in the form of cyclic waves; the concurrent waves of elevated IL-1alpha and M-CSF preceding that of TGFbeta. In addition to providing support for the existence of a humoral response to xRT in patients receiving WFP + PB xRT, the data demonstrated a significant correlation between the integral radiation dose (ID) and the temporal expression and magnitude of plasma IL-1alpha, M-CSF and TGFbeta levels in patients that had received 1-5 fractions (1.8-9Gy) of WFP + PB xRT. Thereafter, the appearance of elevated waves of cytokine expression in the patient's plasma continued independent of additional fractions of WFP + PB xRT.

Expression and regulation of the Na+-K+-2Cl- cotransporter NKCC1 in the normal and CFTR-deficient murine colon

Defective regulation and/or reduced expression of the Na+-K+-2Cl- cotransporter NKCC1 may contribute to the severe secretory defect that is observed in cystic fibrosis, but data concerning the expression and function of NKCC1 in cystic fibrosis transmembrane conductance regulator (CFTR)-deficient cells are equivocal. We therefore investigated NKCC1 mRNA expression, Na+-K+-2Cl- cotransport activity and regulation by cAMP in crypts isolated from the proximal colon of CFTR-containing (CFTR (+/+)) and CFTR-deficient (CFTR (-/-)) mice. mRNA expression levels were determined by semiquantitative PCR, transport rates were measured fluorometrically in 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein acetomethylester (BCECF)-loaded crypts, cytoplasmic volume changes were assessed by confocal microscopy, and [Cl-]i changes were examined by N-(ethoxycarbonylmethyl)-6-methoxyquinolinium bromide (MQAE) quenching. NKCC1 mRNA expression levels were not significantly reduced in CFTR (-/-) crypts compared to controls. Azosemide-sensitive NH4+ influx (used as a measure of Na+-K+-2Cl- cotransport) was 2.23 +/- 0.72 vs. 1.56 +/- 0.16 mM min-1, and increased by 63.6 % in (+/+) and 87.3 % in (-/-) crypts upon stimulation for 5 min with forskolin. After 20 min of stimulation with forskolin, the Na+-K+-2Cl- cotransport rates in (-/-) and (+/+) crypts were identical. Crypt cross-sectional area and [Cl-]i decreased only in (+/+) crypts upon stimulation. In conclusion, normal NKCC1 expression levels, somewhat reduced Na+-K+-2Cl- cotransport rates, but preserved activation by cAMP were found in colonic crypts from CFTR (-/-) mice, ruling out a severe dysfunction of the Na+-K+-2Cl- cotransporter in the CF intestine. Furthermore, these studies establish the existence of a direct, cell-volume- and [Cl-]i-independent activation of colonic NKCC1 by an increase in intracellular cAMP.

cAMP-mediated regulation of murine intestinal/pancreatic Na+/HCO3- cotransporter subtype pNBC1

Basolateral Na(+)-HCO(3)(-) cotransport is essential for intestinal anion secretion, and indirect evidence suggests that it may be stimulated by a rise of intracellular cAMP. We therefore investigated the expression, activity, and regulation by cAMP of the Na(+)-HCO(3)(-) cotransporter isoforms NBC1 and NBCn1 in isolated murine colonic crypts. Na(+)-HCO(3)(-) transport rates were measured fluorometrically in BCECF-loaded crypts, and mRNA expression levels and localization were determined by semiquantitative PCR and in situ hybridization. Acid-activated Na(+)-HCO(3)(-) cotransport rates were 5.07 +/- 0.7 mM/min and increased by 62% after forskolin stimulation. NBC1 mRNA was more abundant in colonic crypts than in surface cells, and crypts expressed far more NBC1 than NBCn1. To investigate whether the cAMP-induced Na(+)-HCO(3)(-) cotransport activation was secondary to secretion-associated changes in HCO(3)(-) or cell volume, we measured potential forskolin-induced changes in intracellular pH and assessed Na(+)-HCO(3)(-) transport activity in CFTR -/- crypts (in which no forskolin-induced cell shrinkage occurs). We found 30% reduced Na(+)-HCO(3)(-) transport rates in CFTR -/- compared with CFTR +/+ crypts but similar Na(+)-HCO(3)(-) cotransport activation by forskolin. These studies establish the existence of an intracellular HCO(3)(-) concentration- and cell volume-independent activation of colonic NBC by an increase in intracellular cAMP.

Comparative analysis of goal achievement during rehabilitation for older and younger adults with spinal cord injury

OBJECTIVE

To evaluate rehabilitation outcome in a representative sample of older and younger SCI patients.

DESIGN

Case series, consecutive sample, survey.

SETTING

Tertiary care, spinal cord injury unit (National Spinal Injuries Centre), Stoke Mandeville Hospital.

PARTICIPANTS

One hundred and forty-seven male and 45 female newly injured in-patients (consisting of 152 younger adults, age range=16 to 54, and 40 older adults, age range=55 to 85) admitted between 1995 and 1999.

INTERVENTION

All patients were actively participating in a comprehensive, multidisciplinary Goal Planning and Needs Assessment rehabilitation programme.

MAIN OUTCOME MEASURE

The Needs Assessment Checklist. Specifically designed and developed for the spinal cord injured population, this clinical assessment tool provides a way of assessing and ensuring that rehabilitation programmes are geared toward each patient's individual needs, providing the patient with the skills appropriate to their level of lesion. As part of ongoing psychometric analyses of the Needs Assessment Checklist, internal consistency reliability coefficients are reported for this measure.

RESULTS

The type and cause of injury for the older adult group in this study was comparable with previous research. Older adults' rehabilitation gains were comparable to those of the younger age group. Younger adults were more mobile initially after their injury. However, when the two groups were matched for injury characteristics etc. the only differences in final outcome between older and younger adults were in skin management ability. Both groups showed significant improvements in all areas of need in the period between mobilisation and entering the pre-discharge ward.

CONCLUSION

These results highlight important considerations for the rehabilitation of older adults and emphasise the need for active, individually tailored rehabilitation programmes. There are specific areas of need (i.e. skin management) where older adults do not achieve comparable levels of independence. Special attention needs to be paid to the problems presented by SCI older adults and efforts should be made to better prepare rehabilitation professionals to adapt to age specific differences.

Conflict in healthcare organizations

Healthcare organizations struggle with internal and external causes of conflict. Successful organizations evaluate and retool existing conflict management systems to constructively, cost-effectively and practically control the negative impact.

Overlapping functions of lysosomal acid phosphatase (LAP) and tartrate-resistant acid phosphatase (Acp5) revealed by doubly deficient mice

To date, two lysosomal acid phosphatases are known to be expressed in cells of the monocyte/phagocyte lineage: the ubiquitously expressed lysosomal acid phosphatase (LAP) and the tartrate-resistant acid phosphatase-type 5 (Acp5). Deficiency of either acid phosphatase results in relatively mild phenotypes, suggesting that these enzymes may be capable of mutual complementation. This prompted us to generate LAP/Acp5 doubly deficient mice. LAP/Acp5 doubly deficient mice are viable and fertile but display marked alterations in soft and mineralised tissues. They are characterised by a progressive hepatosplenomegaly, gait disturbances and exaggerated foreshortening of long bones. Histologically, these animals are distinguished by an excessive lysosomal storage in macrophages of the liver, spleen, bone marrow, kidney and by altered growth plates. Microscopic analyses showed an accumulation of osteopontin adjacent to actively resorbing osteoclasts of Acp5- and LAP/Acp5-deficient mice. In osteoclasts of phosphatase-deficient mice, vacuoles were frequently found which contained fine filamentous material. The vacuoles in Acp5- and LAP/Acp5 doubly-deficient osteoclasts also contained crystallite-like features, as well as osteopontin, suggesting that Acp5 is important for processing of this protein. This is further supported by biochemical analyses that demonstrate strongly reduced dephosphorylation of osteopontin incubated with LAP/Acp5-deficient bone extracts. Fibroblasts derived from LAP/Acp5 deficient embryos were still able to dephosphorylate mannose 6-phosphate residues of endocytosed arylsulfatase A. We conclude that for several substrates LAP and Acp5 can substitute for each other and that these acid phosphatases are essential for processing of non-collagenous proteins, including osteopontin, by osteoclasts.

Reciprocal antagonism between estrogen receptor and NF-kappaB activity in vivo

The functional interaction, or "cross-talk," between estrogen receptor (ER) and the proinflammatory transcription factor nuclear factor (NF)-kappaB demonstrated in vitro has been suggested to play a role in estrogen prevention of cardiovascular disease. Here, we demonstrate that this reciprocal cross-talk occurs in vivo. Ovariectomized C57BL/6 mice fed an atherogenic diet had increased hepatic levels of active NF-kappaB and numerous inflammatory genes, including MHC invariant chain (Ii), vascular cell adhesion molecule-1, tumor necrosis factor-alpha, and RANTES. Treatment with 17alpha-ethinylestradiol (EE) strongly blocked induction of these genes but had no effect on their basal expression levels. ER was required for this activity, because the antagonist ICI 182,780 completely blocked the inhibitory activity of EE. Gene activation by EE was not required for inhibition of inflammatory gene expression, because both the phytoestrogen genistein and low doses of EE were effective in blocking inflammatory gene induction without inducing marker genes such as intestinal trefoil factor (ITF) or myo-inositol-1-phosphate synthase (IPS). The in vivo transcriptional interference was reciprocal, with EE induction of ITF and IPS greatly reduced in animals fed the atherogenic diet versus chow-fed controls. This interference was specific to the liver, because diet had no effect on uterine weight increases produced by EE. Transfection experiments confirmed that the extent of inhibition of ER-mediated transcription by inflammatory stimuli correlated with the extent of NF-kappaB activation. These results suggest that the cross-talk between ER and NF-kappaB does occur in vivo and may indeed contribute significantly to the cardioprotective effects of estrogen.

Mucus altering agents as adjuncts for nonviral gene transfer to airway epithelium

Nonviral vectors have been shown to be a safe and valid alternative to recombinant viruses for gene therapy of cystic fibrosis (CF). Nevertheless, gene transfer efficiency needs to be increased before clinical efficacy is likely in man. One barrier to increased efficacy is normal airway mucus. Using an ex vivo model of sheep tracheal epithelium, we show that this barrier can, in part, be overcome by treatment with the mucolytic agents, Nacystelyn or N-acetylcysteine using either a cationic lipid or a cationic polymer as the gene transfer agent. Further, in vivo application of either Nacystelyn or the anticholinergic glycopyrrolate, both clinically used agents, resulted in increased reporter gene expression in the mouse lung, but no significant correction of the bioelectric defect in CF null mice. These results, whilst unlikely to be sufficient in themselves to achieve clinically relevant gene therapy, may be a further useful step in the attainment of this goal.

Evaluation of post traumatic distress in the first 6 months following SCI

STUDY DESIGN

Cross-sectional questionnaire.

OBJECTIVES

To assess the degree of post traumatic stress symptomatology and its correlates amongst a group of new spinal cord injured patients.

SETTING

The National Spinal Injuries Centre, Stoke Mandeville Hospital NHS Trust.

METHOD

Eighty-five participants with an average age of 32.6 years were assessed between 6 and 24 weeks post injury. Seventeen participants were female. Seventy per cent had complete lesions. Forty per cent had paraplegia and 60% had tetraplegia. Road traffic accidents were the most common cause of injury followed by falls and then sporting accidents. The Impact of Event Scale was used to measure the experience of intrusive thoughts about the trauma and avoidance of trauma related stimuli. Anxiety (SAI), depression (BDI) and dependency (FIM) were also measured.

RESULTS

High levels of distress were evident in 14% of the sample. Trauma-related distress was significantly higher in female patients or patients with high levels of anxiety or depression.

CONCLUSION

In this sample, the rates of trauma-related distress following spinal cord injury were comparable to those found following other traumas and are of clinical significance.

Cellular and molecular characteristics of basal cells in airway epithelium

Basal cells exist as a separate layer of cells covering most of the airway basal lamina. In this central position, they can interact with columnar epithelium, neurons, basement membrane, and the underlying mesenchymal cells. In addition, they interact with inflammatory cells, lymphocytes and dendritic cells. These interactions take place in the lateral intercellular space between basal cells. In this central position basal cells become a very important part of the epithelial-mesenchymal trophic unit of larger airways. In this review it is shown that basal cells may function as progenitor cells of airway epithelium and have a role in attachment of columnar epithelium with the basement membrane. They also have the potential to function in regulation of neurogenic inflammation, the inflammatory response, transepithelial water movement, oxidant defense of the tissue and formation of the lateral intercellular space. Other characteristics of basal cells were not clearly associated with a particular function. The functions for basal cells listed attempt to explain the presence of recently identified molecules in basal cells of airway epithelium. It should be pointed out that specific studies have not been carried out which test the relationship between the molecular functions we describe in this review and the basal cell in airway epithelium.

In vitro-activated human lupus T cells express normal estrogen receptor proteins which bind to the estrogen response element

We have shown that estrogen receptor (ERalpha, ERbeta) transcripts are expressed in SLE and normal T cells. In this study, T cell nuclear extracts from female lupus patients and normal donors were tested for biologically active ER proteins capable of binding to the human estrogen response element (hERE) by electrophoretic mobility shift assays. When peripheral blood T cells were stimulated with 17beta-estradiol (E2), PMA and ionomycin, two major retarded bands in T cell nuclear extracts exhibited a migration pattern similar to slow migrating protein-ERE complexes in human breast cancer cell extracts. T cells cultured only with E2 did not have these complexes. The formation of the complexes was inhibited by competition with the hERE cold oligonucleotide and partially with anti-ERalpha antibodies. There was no notable difference in the migration pattern of ERE-binding proteins between the SLE and normal T cell extracts. Together, these results suggest that activated human T cells, whether lupus-derived or normal-derived, contain biologically active ERalpha proteins. Other factors may be responsible for differential sensitivity of lupus T cells to estrogen.

Enhanced gene delivery to human airway epithelial cells using an integrin-targeting lipoplex

BACKGROUND

Current liposome-based delivery methods for cystic fibrosis (CF) gene therapy are limited by their poor efficiencies. One way to improve this is to use a receptor/ligand interaction to increase binding of the transfection complex with the target cell.

METHODS AND RESULTS

We have tested a synthetic peptide containing an alphav integrin-binding motif (arginine-glycine-aspartic acid, RGD) and a DNA-binding domain (polylysine) for enhancement of liposome-mediated gene delivery. We have shown that integrin proteins capable of binding the RGD motif are located on the apical surface of a polarized human bronchial epithelial cell line (16HBE). Luciferase gene transfer efficiency to subconfluent 16HBE cells was 10-200 times higher than gene transfer using either liposome or peptide alone. This peptide-mediated enhancement was observed at all cellular contact times including those as short as 1 min. Although the transfection efficiency is reduced when the 16HBE cells are grown as polarized monolayers, peptide-mediated enhancement of lipofection is maintained. Transfection with a lipopolyplex containing an RGE (arginine-glucine-glutamic acid) control peptide that cannot bind to the alphav integrin molecules, or competitive inhibition with antibodies against RGD-binding integrins, reduced gene transfer. Confocal microscopy indicated that the peptide increased plasmid delivery to the cell via receptor-mediated endocytosis.

CONCLUSION

These results indicate that integrin-binding peptides represent one way to enhance liposome-mediated gene delivery to pulmonary epithelia.

Effect of anticoagulants and storage temperatures on stability of plasma and serum hormones

OBJECTIVES

To determine the effect of different anticoagulants and storage conditions on the stability of hormones in plasma and serum.

DESIGN AND METHODS

Human blood samples were collected from volunteers into EDTA, lithium heparin, sodium fluoride/potassium oxalate, or tubes without anticoagulant, plasma and serum left at -20 degrees C, 4 degrees C or 30 degrees C for 24 and 120 hours then assayed for ACTH, aldosterone, alpha-subunit, AVP, CRH, C-peptide, estradiol, FSH, glucagon, GH, IGF-1, IGFBP-3, insulin, leptin, LH, PPP, PTH, prolactin and VIP, or at room temperature for 0 to 72 hours (BNP, NT-BNP)(n = 6 per condition).

RESULTS

The anticoagulant altered the measured concentrations for 9 hormones when compared to EDTA. All hormones except ACTH were stable for > 120 hours in EDTA or fluoride at 4 degrees C, but only 13 hormones were stable in all anticoagulants. At 30 degrees C, 8 hormones were stable for > 120 hours in EDTA, and 3 hormones in all anticoagulants. BNP and NT-BNP were stable for < 24 hours when stored in EDTA or heparin at room temperature.

DISCUSSION

Storage of samples in EDTA plasma at 4 degrees C is suitable for most hormones (except ACTH) for up to 120 hours.

Prior exposure to aged and diluted sidestream cigarette smoke impairs bronchiolar injury and repair

The bronchiolar injury/repair response to naphthalene (NA) in mice includes acute distal airway epithelial injury that is followed by epithelial proliferation and redifferentiation, which result in repair of the epithelium within 14 days. To test whether prior exposure to aged and diluted sidestream cigarette smoke (TS) would alter the injury/repair response of the airway epithelium, adult mice were exposed to either filtered air (FA) or smoke for 5 days before injection with either corn oil carrier (CO) or naphthalene. Mice were killed 1 and 14 days after naphthalene injury. Lung and lobar bronchus were examined and measured using high-resolution epoxyresin sections. The control group (FACOFA) that was exposed to filtered air/corn oil/filtered air contained airway epithelium similar to untreated controls at all airway levels. The group exposed to tobacco smoke/corn oil/filtered air (TSCOFA) contained some rounded cells in the small airways and some expansion of the lateral intercellular space in the larger airways. Necrotic or vacuolated cells were not observed. As expected, the epithelium in the group exposed to filtered air/naphthalene/filtered air (FANAFA) contained many light-staining vacuolated Clara cells and squamated ciliated cells within distal bronchioles during the acute injury phase. Repair (including redifferentiation of epithelial cells and restoration of epithelial thickness) was nearly complete 14 days after injury. The extent of Clara cell injury, as assessed in lobar bronchi, was not different between the four groups. Although the FANAFA group contained greater initial injury in the distal airways at 1 day, the group exposed to tobacco smoke/naphthalene/filtered air (TSNAFA) had the least amount of epithelial repair at 14 days after naphthalene treatment; many terminal bronchioles contained abundant squamated undifferentiated epithelium. We conclude that tobacco smoke exposure prior to injury (1) does not change the target site or target cell type of naphthalene injury, since Clara cells in terminal bronchioles are still selectively injured; (2) results in slightly diminished acute injury from naphthalene in distal bronchioles; and (3) delays bronchiolar epithelial repair.

Acetylcholine induces cytosolic Ca2+ mobilization in isolated distal colonic crypts from normal and cystic fibrosis mice

In intestinal biopsies from cystic fibrosis (CF) patients acetylcholine fails to elicit a chloride secretion response, and this observation can be explained by a defect in the Ca2+ signalling pathway in CF secretory cells. We tested the hypothesis that in CF intestine, the generation of an intracellular Ca2+ signal upon cholinergic stimulation is absent. A transgenic CF mouse model was used. Electrical measurements on intact jejunum and unstripped colon were performed in Ussing chambers. Intact distal colonic crypts were isolated, and the intracellular Ca2+ concentration was monitored using the Ca2+-sensitive dye fura-2. Acetylcholine increased the short-circuit current generated by wild-type jejunum and colon, but failed to induce a response in CF tissues. Acetylcholine caused a transient elevation in the intracellular Ca2+ concentration in colonic crypts from both wild-type and CF mice; the amplitude and timing of the response in CF crypts was indistinguishable from that in wild-type crypts. The response to acetylcholine was also observed in the absence of extracellular calcium, indicating intracellular stores as the source from which the cytosolic Ca2+ concentration increased. We conclude that the absence of a cholinergically-induced secretory response in CF intestine is not due to a defect in the generation of a Ca2+ signal in intestinal cells upon cholinergic stimulation.

Lessons learned while compiling a quantitative exposure database from the published literature

The published literature was reviewed and then a quantitative hydrocarbon solvent exposure database was compiled. The data was then analyzed to determine trends in documented worker exposures to hydrocarbon solvents. It was found that an all too common limitation of the published literature was the incomplete reporting of results by the authors.

Mice lacking tartrate-resistant acid phosphatase (Acp 5) have disordered macrophage inflammatory responses and reduced clearance of the pathogen, Staphylococcus aureus

Tartrate-resistant acid phosphatase (TRAP) is a lysosomal di-iron protein of mononuclear phagocytes and osteoclasts. Hitherto, no role for the enzyme in immunity has been identified; however, knockout mice lacking TRAP have a skeletal phenotype caused by an intrinsic osteoclast defect. To investigate a putative function for TRAP in macrophages (Mphi), we investigated proinflammatory responses and systemic microbial clearance in knockout mice compared with age- and gender-matched congenic wild-type mice. Phorbol 12-myristate 13-acetate (PMA)-stimulated and interferon-gamma (IFN-gamma)-induced superoxide formation was enhanced in peritoneal Mphi lacking TRAP; nitrite production in response to stimulation with lipopolysaccharide (LPS) and IFN-gamma was also increased. In addition, secretion of the proinflammatory cytokines, tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-1beta and IL-12, was significantly greater in TRAP-deficient Mphi when stimulated with LPS, with or without addition of either TNF-alpha or IFN-gamma. The activity of tartrate-sensitive (lysosomal) acid phosphatase was increased in Mphi from the knockout mice but activities of the lysosomal hydrolases N-acetyl beta-glucosaminidase and acid beta-glucuronidase were unchanged, indicating selective activation of compensatory acid phosphatase activity. Evidence of impaired Mphi function in vivo was obtained in TRAP knockout mice, which showed delayed clearance of the microbial pathogen, Staphylococcus aureus, after sublethal intraperitoneal inoculation. After microbial challenge, peritoneal exudates obtained from TRAP knockout mice had a reduced population of Mphi. As peritoneal Mphi and neutrophils lacking TRAP were able to phagocytose and kill S. aureus normally in vitro, TRAP may directly or indirectly influence recruitment of Mphi to sites of microbial invasion. Our study shows that TRAP participates in the inflammatory response of the Mphi and influences effector signalling pathways in innate immunity.

Inflammation in cystic fibrosis airways: relationship to increased bacterial adherence

It is unclear whether inflammation in the cystic fibrosis (CF) lung relates predominantly to bacterial infection, or occurs as a direct consequence of mutant cystic fibrosis transmembrane conductance regulator (CFTR) protein. Interleukin (IL)-8 secretion from CF and non-CF cell lines, and from CF and non-CF human primary nasal epithelial cells incubated with or without Pseudomonas aeruginosa, was measured. Activation of nuclear factor-kappaB (NF-kappaB) in unstimulated CF and non-CF nasal epithelial cells, cell lines and murine tissues was measured by gel-shift assays. No significant difference in basal IL-8 production or NF-kappaB activation was observed between CF and non-CF primary nasal cells. However, CF cells exhibited a significantly (p<0.01) increased IL-8 secretion following P. aeruginosa stimulation. Equalization of the increased P. aeruginosa adherence observed in CF cells, to non-CF levels, resulted in comparable IL-8 secretion. Further, IL-8 production did not differ with mutations which result in either correctly localized CFTR, or in partial/total mislocalization of this protein. Similar levels of NF-kappaB activation were observed in a number of organs of wildtype and CF mice. Finally, IL-8 secretion and NF-kappaB activity were not consistently increased in CF cell lines. Cos-7 cell transfection with plasmids expressing deltaF508 or G551D mutant CFTR protein resulted in increased activation of a p50-containing NF-kappaB complex, but IL-8 secretion was similar to wild-type cells. The authors conclude that the stimulus produced by Pseudomonas aeruginosa is the predominant inflammatory trigger in their models.

Hydrocarbon solvent exposure data: compilation and analysis of the literature

An occupational exposure database for hydrocarbon solvent end-use applications was constructed from the published literature. The database provides exposure assessment information for such purposes as regulatory risk assessments, support of industry product stewardship initiatives, and identification of applications in which limited exposure data are available. It is quantitative, documented, and based on credible data. Approximately 350 articles containing quantitative hydrocarbon solvent exposure data were identified using a search of computer databases of published literature. Many articles did not report sufficient details of the exposure data for inclusion in the database (e.g., full-shift exposure or task-based exposure data). Others were excluded because only limited summary statistics were provided, which precluded statistical analysis of the data (e.g., arithmetic mean concentration presented, but no sample number). Following evaluation, 16,880 hydrocarbon solvent exposure measurements from 99 articles were entered into a database for analysis. Methods used to identify and evaluate published solvent exposure data are described along with more detailed analysis of worker exposure to hydrocarbon solvents in three major end-use applications: painting and coating, printing, and adhesives. Solvent exposures were evaluated against current ACGIH threshold limit values (TLVs) and trends were identified. Limited quantitative data are available prior to 1970. In general, reported hydrocarbon solvent exposures decreased fourfold from 1960 to 1998, were below the TLVs applicable to specific hydrocarbon solvents at the time, and on average have been below 40% of the TLV since 1980. The database already has proved valuable; however, the utility of published exposure data could be further improved if authors consistently reported essential data elements and supporting information.