Use of spatially distributed time-integrated sediment sampling networks and distributed fine sediment modelling to inform catchment management.

Under the EU Water Framework Directive, suspended sediment is omitted from environmental quality standards and compliance targets. This omission is partly explained by difficulties in assessing the complex dose-response of ecological communities. But equally, it is hindered by a lack of spatially distributed estimates of suspended sediment variability across catchments. In this paper, we demonstrate the inability of traditional, discrete sampling campaigns for assessing exposure to fine sediment. Sampling frequencies based on Environmental Quality Standard protocols, whilst reflecting typical manual sampling constraints, are unable to determine the magnitude of sediment exposure with an acceptable level of precision. Deviations from actual concentrations range between -35 and +20% based on the interquartile range of simulations. As an alternative, we assess the value of low-cost, suspended sediment sampling networks for quantifying suspended sediment transfer (SST). In this study of the 362 km2 upland Esk catchment we observe that spatial patterns of sediment flux are consistent over the two year monitoring period across a network of 17 monitoring sites. This enables the key contributing sub-catchments of Butter Beck (SST: 1141 t km2 yr-1) and Glaisdale Beck (SST: 841 t km2 yr-1) to be identified. The time-integrated samplers offer a feasible alternative to traditional infrequent and discrete sampling approaches for assessing spatio-temporal changes in contamination. In conjunction with a spatially distributed diffuse pollution model (SCIMAP), time-integrated sediment sampling is an effective means of identifying critical sediment source areas in the catchment, which can better inform sediment management strategies for pollution prevention and control.

Heparin and structurally related polymers attenuate eotaxin-1 (CCL11) release from human airway smooth muscle.

BACKGROUND AND PURPOSE: The glycosaminoglycan heparin has anti-inflammatory activity and is exclusively found in mast cells, which are localized within airway smooth muscle (ASM) bundles of asthmatic airways. Interleukin (IL)-13 induces the production of multiple inflammatory mediators from ASM including the eosinophil chemoattractant chemokine, eotaxin-1. Heparin and related glycosaminoglycan polymers having structurally heterogeneous polysaccharide side chains that varied in molecular weight, sulphation and anionic charge were used to identify features of the heparin molecule linked to anti-inflammatory activity. EXPERIMENTAL APPROACH: Cultured human ASM cells were stimulated with interleukin (IL)-13 in the absence or presence of heparin and related polymers. Eotaxin-1 was quantified using chemokine antibody arrays and ELISA. KEY RESULTS: Unfractionated heparin attenuated IL-13-dependent eotaxin-1 production and this effect was reproduced with low molecular weight heparins (3 and 6 kDa), demonstrating a minimum activity fragment of at least 3 kDa. N-desulphated, 20% re-N-acetylated heparin (anticoagulant) was ineffective against IL-13-dependent eotaxin-1 production compared with 90% re-N-acetylated (anticoagulant) or O-desulphated (non-anticoagulant) heparin, suggesting a requirement for N-sulphation independent of anticoagulant activity. Other sulphated molecules with variable anionic charge and molecular weight exceeding 3 kDa (dextran sulphate, fucoidan, chondroitin sulphate B) inhibited IL-13-stimulated eotaxin-1 release to varying degrees. However, non-sulphated dextran had no effect. CONCLUSIONS: Inhibition of IL-13-dependent eotaxin-1 release by heparin involved but did not depend upon sulphation, though loss of N-sulphation reduced the attenuating activity, which could be restored by N-acetylation. This anti-inflammatory effect was also partially dependent on anionic charge, but independent of molecular size above 3 kDa and the anticoagulant action of heparin.

Proinflammatory cytokines upregulate mRNA expression and secretion of vascular endothelial growth factor in cultured human airway smooth muscle cells.

Airflow obstruction in chronic airway disease is associated with airway and pulmonary vascular remodeling, of which the molecular mechanisms are poorly understood. Paracrine actions of angiogenic factors released by resident or infiltrating inflammatory cells following activation by proinflammatory cytokines in diseased airways could play a major role in the airway vascular remodeling process. Here, the proinflammatory cytokines interleukin (IL)-1beta, and tumor necrosis factor (TNF)-alpha were investigated on cell cultures of human airway smooth muscle (ASM) for their effects on mRNA induction and protein release of the angiogenic peptide, vascular endothelial growth factor (VEGF). IL-1beta (0.5 ng/mL) and TNF-alpha (10 ng/mL) each increased VEGF mRNA (3.9 and 1.7 kb) expression in human ASM cells, reaching maximal levels between 16 and 24 and 4 and 8 h, respectively. Both cytokines also induced a time-dependent release of VEGF, which was not associated with increased ASM growth. Preincubation of cells with 1 microM dexamethasone abolished enhanced release of VEGF by TNF-alpha. The data suggest that human ASM cells express and secrete VEGF in response to proinflammatory cytokines and may participate in paracrine inflammatory mechanisms of vascular remodeling in chronic airway disease.

Quality of care for women presenting with benign breast conditions.

The aim of the study was to investigate the management of women with benign breast problems. A consecutive sample of women (n = 194) was assessed who presented to public or private sector providers. The main reasons for referral were breast lumps (62%); 56% of women who attended the public sector did not receive any recommendation compared to 40% who attended the private sector and clinical/general practitioner reviews were recommended to more women in the private sector (54%). Reasons for the discrepancy between public and private patients require further investigation.

Regional variation in ICC distribution, pacemaking activity and neural responses in the longitudinal muscle of the murine stomach.

Intramuscular interstitial cells of Cajal (ICC-IM) play a critical role in enteric neural regulation of the circular muscle layer in the stomach, but no studies have been performed on the longitudinal layer. Kit immunohistochemistry was used to examine ICC-IM in the longitudinal muscle layer of the murine corpus and antrum, and it revealed marked heterogeneity in the distribution of ICC-IM in longitudinal muscles. In the corpus, ICC-IM were found along the greater curvature near the fundus. ICC-IM decreased in density in the circumferential axis toward the lesser curvature and in the longitudinal axis toward the antrum. ICC-IM were absent from the longitudinal layer of the antrum. Double labelling with markers for specific classes of enteric motor neurones revealed that cholinergic and nitrergic motor neurones formed close contacts with ICC-IM in the corpus but not in the antrum. Enteric nerve stimulation evoked prominent cholinergic excitatory and nitrergic inhibitory responses in longitudinal muscles of the corpus, but not in the antrum of wild-type animals. Cholinergic and nitrergic nerves were also present in W/W(V) mice, but functional innervation of the longitudinal muscle layer by these nerves in the corpus and antrum were absent. The data show that cholinergic and nitrergic neurotransmission only occurs in the gastric longitudinal layer in regions where ICC-IM are present. In regions, such as the corpus, where ICC-IM are common, robust neural responses are present, but the reduced density of ICC-IM near the lesser curvature and in the distal stomach leads to reduced neural regulation in these gastric regions.

Inhibitors of mitogen-activated protein kinases differentially regulate eosinophil-activating cytokine release from human airway smooth muscle.

Airway smooth muscle (ASM) is a potential source of multiple proinflammatory cytokines during airway inflammation. In the present study, we examined a requirement for mitogen-activated protein (MAP) kinase activation for interleukin (IL)-1beta-stimulated GM-CSF, RANTES, and eotaxin release. IL-1beta induced concentration-dependent phosphorylation of p42/p44 extracellular signal-regulated kinases (ERKs), p38 MAP kinase, and c-Jun amino-terminal kinase (SAPK/JNK). p42/p44 ERK and p38 MAP kinase phosphorylation peaked at 15 min and remained elevated up to 4 h. SAPK/JNK phosphorylation also peaked at 15 min but fell to baseline within 60 min. SB 203580 selectively inhibited IL-1beta-stimulated activation of p38 MAP kinase; U 0126 was selective against p42/p44 ERK activity. SB 202474, an inactive analog, had no effect on p42/p44 ERK, p38 MAP kinase, or SAPK/JNK activation, or on eotaxin or RANTES release. Eotaxin release was inhibited by SB 203580 and U 0126, whereas RANTES release was prevented by U 0126 only. GM-CSF release was inhibited by U 0126 but enhanced by SB 203580. These data indicate that RANTES release is dependent on p42/p44 ERK activation but occurs independently of p38 MAP kinase activity. Eotaxin release, however, is dependent on both p38 MAP kinase- and p42/p44 ERK-dependent mechanisms. GM-CSF release is p42/p44 ERK dependent and is tonically suppressed by a mechanism that is partially dependent on p38 MAP kinase, though direct inhibition of cyclooxygenase (COX) activity due to poor inhibitor selectivity may also contribute.

Mislocalization of melanosomal proteins in melanocytes from mice with oculocutaneous albinism type 2.

More than 10% of admissions worldwide to institutions for the visually impaired are due to some form of albinism. The most common form, oculocutaneous albinism type 2, results from mutations at the p locus. The function of the p gene is yet to be determined. It has been shown that melanocytes from p -null mice exhibit an abnormal melanosomal ultrastructure in addition to alterations in activity and localization of tyrosinase, a critical melanogenic enzyme. In light of these observations, we examined tyrosinase trafficking in p -null vs wildtype mouse melanocytes in order to explore p function. Electron microscopy of wildtype melan-a and p -null melan-p1 cells demonstrated accumulation of tyrosinase in 50 nm vesicles throughout the cell in the absence of p, an observation corroborated by an increase in tyrosinase activity in vesicle-enriched fractions from melan-p1 compared to melan-a cells. Misrouting in the absence of p was not limited to tyrosinase; a second melanosomal protein, tyrosinase-related protein 1, also trafficked incorrectly. In melan-p1, mislocalization led to secretion of tyrosinase into the medium. Adding tyrosine to the medium was found to partially correct tyrosinase trafficking and to reduce secretion; the cysteine protease inhibitor E64 also reduced secretion. We propose that p is required by melanocytes for transport of melanosomal proteins. In its absence, tyrosinase accumulates in vesicles and, in cultured melanocytes, is proteolysed and secreted.

Release of biologically active TGF-beta from airway smooth muscle cells induces autocrine synthesis of collagen.

In severe or chronic asthma, there is an increase in airway smooth muscle cell (ASMC) mass as well as an increase in connective tissue proteins in the smooth muscle layer of airways. Transforming growth factor-beta (TGF-beta) exists in three isoforms in mammals and is a potent regulator of connective tissue protein synthesis. Using immunohistochemistry, we had previously demonstrated that ASMCs contain large quantities of TGF-beta1-3. In this study, we demonstrate that bovine ASMC-derived TGF-beta associates with the TGF-beta latency binding protein-1 (LTBP-1) expressed by the same cells. The TGF-beta associated with LTBP-1 localizes TGF-beta extracellularly. Furthermore, plasmin, a serine protease, regulates the secretion of a biologically active form of TGF-beta by ASMCs as well as the release of extracellular TGF-beta. The biologically active TGF-beta released by plasmin induces ASMCs to synthesize collagen I in an autocrine manner. The autocrine induction of collagen expression by ASMCs may contribute to the irreversible fibrosis and remodeling seen in the airways of some asthmatics.

beta(2)-adrenoceptor agonists inhibit release of eosinophil-activating cytokines from human airway smooth muscle cells.

1. Airway smooth muscle (ASM) is a potential source of multiple pro-inflammatory cytokines during airway inflammation. beta-Adrenoceptor agonist hyporesponsiveness is a characteristic feature of asthma, and interleukin (IL)-1 beta and tumour necrosis factor (TNF)-alpha are implicated in its cause. Here, the capacity of beta-adrenoceptor agonists to prevent release of GM-CSF, RANTES, eotaxin and IL-8, elicited by IL-1 beta or TNF alpha, was examined in human ASM cells. 2. Isoprenaline (approximately EC(50) 150 nM), a non-selective beta-adrenoceptor agonist, and salbutamol ( approximately EC(50) 25 nM), a selective beta(2)-adrenoceptor agonist, attenuated release of GM-CSF, RANTES and eotaxin, but not IL-8 (EC(50) >1 microM). The maximum extent of attenuation was RANTES > or = eotaxin > GM-CSF >> IL-8, and was prevented by either propranolol (1 microM), a non-selective beta-adrenoceptor antagonist, or ICI 118511 (IC(50) 15 nM), a selective beta(2)-adrenoceptor antagonist. 3. The cyclic AMP-elevating agents, dibutyryl cyclic AMP ( approximately EC(50) 135 microM), forskolin ( approximately EC(50) 530 nM) and cholera toxin ( approximately EC(50) 575 pg ml(-1)) abolished IL-1 beta-induced release of GM-CSF, RANTES and eotaxin, but not IL-8. 4. IL-1 beta (1 ng ml(-1)) attenuated early increases (up to 1 h) in cyclic AMP formation induced by salbutamol (1 microM), but not by forskolin (10 microM). The cyclo-oxygenase inhibitor, indomethacin (1 microM) prevented later increases (3 - 12 h) in IL-1 beta-stimulated cyclic AMP content, but did not prevent the attenuation by salbutamol of IL-1 beta-induced cytokine release. 5. We conclude in human ASM cells that activation of beta(2)-adrenoceptors and generation of cyclic AMP is negatively-linked to the release, elicited by IL-1 beta or TNF alpha, of eosinophil-activating cytokines such as GM-CSF, RANTES and eotaxin, but not IL-8.

"I hated those darn chickens...": the power in stories for older adults and nurses.

Attention to stories provides a holistic view of an older adult and offers the potential for quality nursing intervention. Explored in this article is the power of stories to advance the well being of older adults and the implications for gerontological nurses of a commitment to support storytelling in this population.

A new name for parasitology today

Parasitology Today is officially the Number One ranked journal in parasitology (impact factor 4.940). Since its launch in 1985, Parasitology Today has been part of the Trends Journal series - the most highly cited group of monthly review journals in the world, that includes Trends in Biochemical Sciences, Trends in Microbiology, Trends in Genetics, Immunology Today and Trends in Cell Biology.

Differential activity of conditional MYC and its variant MYC-S in human mortal fibroblasts.

We have explored the effects of the conditional MYC-estrogen receptor fusion protein, MYC-ERTM, in human mortal fibroblasts, WI38, on cell-cycle entry, apoptosis and gene expression. The results indicate that activation of MYC-ERTM in WI38 cells is sufficient to cause S phase entry of quiescent cells, which is preceded by phosphorylation of Rb and activation of the Cdk2-associated kinase. We also analysed the MYC protein variant, MYC-S, which lacks part of the transcriptional activation domain but includes the conserved MYC box II and 26 amino acids N-terminal to it. MYC-S was previously shown to promote proliferation and apoptosis of immortalized rodent cell lines. The results indicate that MYC-S has undetectable activity as an inducer of S phase or apoptosis of quiescent WI38 cells. However, Myc-S stimulates proliferation of WI38 cells in the presence of 10% fetal calf serum. Surprisingly, we found that MYC-S, previously considered solely a repressor of specific reporter genes, is instead a weak transactivator of endogenous target genes both in mortal and immortalized cells. In addition, MYC-S exhibit a weak repressor activity upon an endogenous target gene only in immortalized cells. MYC-S transcriptional properties suggest that MYC box II and the adjacent N-terminal amino acids, while not sufficient for full repression function, participate in transactivation of endogenous target genes.

Differential effects of extracellular matrix proteins on human airway smooth muscle cell proliferation and phenotype.

Mature airway smooth muscle cells are characterized by a low proliferative index and expression of contractile marker proteins such as smooth muscle alpha-actin (sm-alpha-actin), calponin, and smooth muscle myosin heavy chain (sm-MHC). In the present study, defined extracellular matrix (ECM) components were examined on the proliferative and phenotypic status of mitogen-stimulated, cultured human airway smooth muscle cells. The results demonstrate that although cells adhered and spread on plates precoated with (1 to 100 microg/ml) of fibronectin (FN), collagen I (Col I), laminin (LN), or Matrigel, their subsequent proliferative response varied qualitatively. FN and Col I enhanced proliferation in response to either platelet-derived growth factor (PDGF)-BB or alpha-thrombin, compared with cells on plastic. LN, however, reduced mitogen-stimulated proliferation. A similar reduction was found in cells cultured on Matrigel. The effect of ECM substrates on contractile phenotype was determined by examining cellular expression of sm-alpha-actin, sm-MHC, and calponin using immunocytochemical and flow cytometric methods. Approximately 75% of PDGF-BB-stimulated cells, cultured on LN or Matrigel, expressed sm-alpha-actin, calponin, and sm-MHC, but only 8 to 10% stained for the Ki67 nuclear antigen proliferation marker. In contrast, more than 75% of cells cultured on FN or Col I were positive for Ki67 antigen, but only 20% were positive for contractile proteins. Flow cytometric analysis of sm-alpha-actin and DNA content confirmed the immunocytochemical findings and showed that the observed reduction in sm-alpha-actin content after culture on FN or Col I, compared with LN and Matrigel, occurred in the majority of the cell population, supporting bidirectional phenotype modulation. Overall, the data suggest that ECM substrates modulate both proliferation and phenotype of human airway smooth muscle cells in culture.

Phenotypic diversity and molecular mechanisms of airway smooth muscle proliferation in asthma.

Chronic persistent asthma is characterized by poorly reversible airflow obstruction and airways inflammation and remodelling. Histopathological studies of airways removed at post mortem from patients with severe asthma reveal marked inflammatory and architectural changes associated with airway wall thickening. Increased airway smooth muscle content, occurring as a result of hyperplastic and/or hypertrophic growth, is believed to be one of the principal contributors to airway wall thickening. In recent years, significant advances have been made in elucidating the mediators and the intracellular pathways that regulate proliferation of airway smooth muscle. The contribution that smooth muscle makes to persistent airflow obstruction may not, however, be limited simply to its increased bulk within the airway wall. Interest is growing in the possibility that reversible phenotypic modulation and increased heterogeneity of airway smooth muscle function may also be a feature of the asthmatic airway. This review focuses on possible mechanisms controlling smooth muscle phenotype heterogeneity as well as on the mediators and intracellular pathways implicated in its cellular proliferation. Particular attention is paid to mechanisms involving activation of the extracellular signal regulated kinase-, protein kinase C- and phosphoinositide 3-kinase-dependent pathways, since these appear to be the major candidate second messenger pathways for G protein- and tyrosine kinase-coupled receptor-stimulated proliferation.

Airway smooth muscle as a target in asthma.

Traditionally, the contractile properties of airway smooth muscle have been regarded as its sole contribution to the pathogenesis of asthma. However, our understanding of the role that this structural cell plays in asthma is changing. Airway smooth muscle can undergo hyperplasia and/or hypertrophy leading to structural changes in the airway wall which contribute to the development of persistent airway obstruction and increased non-specific airway hyperresponsiveness in chronic severe asthma. Many studies in vitro have characterized airway smooth muscle proliferation induced by various pro-inflammatory mediators, growth factors and components of the extracellular matrix, but the mediator(s) responsible for the observed increase in airway wall smooth muscle content in vivo remain to be determined. In addition to geometric obstruction by increased airway wall thickening, proliferating airway smooth muscle cells undergo phenotypic modulation from a contractile to synthetic-proliferative state where additional functions of airway smooth muscle such as cytokine/chemokine and extracellular matrix secretion may become more apparent. This may be especially relevant in the diseased airway where the content of airway smooth muscle as a fraction of the total cells present in the airway wall is already increased. Airway smooth muscle cells may also interact by direct contact with immunocytes such as T lymphocytes through expression of cell adhesion molecules with the result that myocyte DNA synthesis is induced. As additional functions of airway smooth muscle are described, a more contemporary view is emerging that airway smooth cells may adopt an immuno-effector role in chronic asthma by proliferating, secreting cytokines, expressing adhesion molecules and by interacting with various inflammatory cells. This may involve changes in the phenotypic status of airway smooth muscle, and as a result, these cells may play an active role in perpetuating and orchestrating airway inflammation in the remodelled airway. An important phase for future airway smooth muscle research will be to determine the extent that these putative mechanisms exist in vivo in the pathogenesis of chronic severe asthma.

Tumor necrosis factor-alpha enhances mRNA expression and secretion of interleukin-6 in cultured human airway smooth muscle cells.

Airway smooth muscle (ASM) is considered to be an end-target cell for the effects of mediators released during airway wall inflammation. Several reports suggest that activated ASM may be capable of generating various proinflammatory cytokines. We investigated the effects of tumor necrosis factor (TNF)-alpha, a potent proinflammatory cytokine, on cultured human ASM cells by examining the expression and release of the cytokine interleukin (IL)-6, cell proliferation, and the expression pattern of c-fos and c-jun, two nuclear proto-oncogenes constituting the activator protein-1 transcription factor. Growth-arrested cell monolayers were stimulated with human recombinant TNF-alpha in a concentration- and time-dependent manner. TNF-alpha stimulated the expression of IL-6 messenger RNA (mRNA), which was detected after 15 min, reaching a maximum at 1 h. IL-6 protein was readily detected in ASM cell-conditioned medium after 2 h of TNF-alpha stimulation. Protein levels increased in a time- and concentration-dependent manner. Release of IL-6 elicited by TNF-alpha was significantly inhibited by dexamethasone, cycloheximide, and nordihydroguaiaretic acid (NDGA). TNF-alpha did not alter DNA biosynthesis up to 48 h or cell numbers up to 120 h. Northern blot analysis of proto-oncogene expression revealed that c-fos and c-jun mRNA levels were elevated after 30 min of TNF-alpha incubation with maximum levels at 1 h and 45 min, respectively. Expression of c-fos mRNA was downregulated by NDGA. Four hours of TNF-alpha treatment resulted in translocation of c-jun immunofluorescence from the cytoplasm to the nucleus in human ASM cells. Our results suggest that despite the lack of a mitogenic response to TNF-alpha, upregulation of primary response genes in human ASM cells may account for the induction of proinflammatory cytokines, such as IL-6, in human airways.

Resident abuse: an insider's perspective.

The purpose of this study was to assess how resident abuse is perceived by members of the long-term care institution. Groups of registered nurses, nonprofessional staff, older residents, and significant others were interviewed individually and participated in focus groups. Resident abuse is perceived by the participants in this study as an experience that causes a perception of hurt in older residents. This perception is voiced by either older residents themselves or other members of the institution on their behalf. Participants' views about resident abuse are always framed within the context of institutional life.