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1.
Biodivers Data J ; (7): e30124, 2019.
Article in English | MEDLINE | ID: mdl-30820161

ABSTRACT

BACKGROUND: A parasitoid wasp, Trissolcus solocis Johnson, was recorded parasitising eggs of the invasive stink bug Halyomorpha halys (Stål), in the United States. This is the first record of this species parasitising eggs of H. halys. NEW INFORMATION: First record of Trissolcus solocis parasitising Halyomorpha halys eggs in the United States and first record of T. solocis in Alabama.

2.
J Hosp Infect ; 100(4): e226-e232, 2018 Dec.
Article in English | MEDLINE | ID: mdl-29752996

ABSTRACT

BACKGROUND: Mycobacterium tuberculosis is a major health burden worldwide. The disease may present as an individual case, community outbreak, or more rarely as a nosocomial outbreak. Even in countries with a low prevalence such as the UK, tuberculosis (TB) presents a risk to healthcare workers (HCWs). AIM: To report an outbreak which manifested 12 months after a patient with pulmonary tuberculosis was admitted to Queen Elizabeth Hospital Birmingham. METHODS: We present the epidemiological and outbreak investigations; the role of whole genome sequencing (WGS) in identifying the outbreak and control measures to prevent further outbreaks. FINDINGS: Subsequent to a diagnosis of open TB in a patient, transmission was confirmed in one HCW who had active TB; HCWs with latent TB infection (LTBI) were also identified among seven HCW contacts of the index patient. Of note, all the LBTI patients had other risk factors for TB. Routine use of WGS identified the outbreak link between the index patient and the HCW with active TB disease, and informed our investigations. CONCLUSION: Exposure most likely occurred during an aerosol-generating procedure (AGP) which was done in accordance with national guidance at that time without using respiratory protection. Enhanced control measures were implemented following the outbreak.


Subject(s)
Cross Infection/epidemiology , Disease Outbreaks , Disease Transmission, Infectious , Health Personnel , Mycobacterium tuberculosis/isolation & purification , Tuberculosis/epidemiology , Adult , Child, Preschool , Cross Infection/transmission , Female , Humans , Infant , Infection Control/methods , Male , Middle Aged , Molecular Epidemiology , Molecular Typing , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/genetics , Prevalence , Risk Factors , Tuberculosis/transmission , United Kingdom/epidemiology , Whole Genome Sequencing
3.
Sci Rep ; 5: 8273, 2015 Feb 05.
Article in English | MEDLINE | ID: mdl-25653128

ABSTRACT

Predicted increases in seawater temperatures accelerate coral reef decline due to mortality by heat-driven coral bleaching. Alteration of the natural nutrient environment of reef corals reduces tolerance of corals to heat and light stress and thus will exacerbate impacts of global warming on reefs. Still, many reefs demonstrate remarkable regeneration from past stress events. This paper investigates the effects of sea surface temperature (SST) and water column productivity on recovery of coral reefs. In 71 Indo-Pacific sites, coral cover changes over the past 1-3 decades correlated negative-exponentially with mean SST, chlorophyll a, and SST rise. At six monitoring sites (Persian/Arabian Gulf, Red Sea, northern and southern Galápagos, Easter Island, Panama), over half of all corals were <31 years, implying that measured environmental variables indeed shaped populations and community. An Indo-Pacific-wide model suggests reefs in the northwest and central Indian Ocean, as well as the central west Pacific, are at highest risk of degradation, and those at high latitudes the least. The model pinpoints regions where coral reefs presently have the best chances for survival. However, reefs best buffered against temperature and nutrient effects are those that current studies suggest to be most at peril from future ocean acidification.


Subject(s)
Coral Reefs , Seawater , Temperature , Animals , Anthozoa/classification , Anthozoa/genetics , Chlorophyll/genetics , Chlorophyll A , Ecosystem , Indian Ocean , Microsatellite Repeats , Oceanography , Pacific Ocean , Regeneration
4.
Cell Death Differ ; 18(2): 191-200, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21217767

ABSTRACT

Huntington's disease (HD) is a fatal neurodegenerative disorder caused by expansion of a polyglutamine tract in the huntingtin protein (htt) that mediates formation of intracellular protein aggregates. In the brains of HD patients and HD transgenic mice, accumulation of protein aggregates has been causally linked to lesions in axo-dendritic and synaptic compartments. Here we show that dendritic spines - sites of synaptogenesis - are lost in the proximity of htt aggregates because of functional defects in local endosomal recycling mediated by the Rab11 protein. Impaired exit from recycling endosomes (RE) and association of endocytosed protein with intracellular structures containing htt aggregates was demonstrated in cultured hippocampal neurons cells expressing a mutant htt fragment. Dendrites in hippocampal neurons became dystrophic around enlarged amphisome-like structures positive for Rab11, LC3 and mutant htt aggregates. Furthermore, Rab11 overexpression rescues neurodegeneration and dramatically extends lifespan in a Drosophila model of HD. Our findings are consistent with the model that mutant htt aggregation increases local autophagic activity, thereby sequestering Rab11 and diverting spine-forming cargo from RE into enlarged amphisomes. This mechanism may contribute to the toxicity caused by protein misfolding found in a number of neurodegenerative diseases.


Subject(s)
Dendritic Spines/ultrastructure , Huntington Disease/metabolism , rab GTP-Binding Proteins/metabolism , Animals , Dendritic Spines/metabolism , Disease Models, Animal , Drosophila/metabolism , Endosomes/metabolism , Huntingtin Protein , Huntington Disease/pathology , Mice , Mice, Transgenic , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neurons/metabolism , Neurons/pathology , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , PC12 Cells , Rats
5.
Ann Oncol ; 19(7): 1327-1330, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18349031

ABSTRACT

BACKGROUND: Reported median overall survival (OS) in patients with mantle cell lymphoma (MCL) has been reported to be just 3-4 years. As a consequence, first-line treatment has become more aggressive. Single-center studies with R-Hyper-CVAD and/or autologous stem-cell transplant (ASCT) have produced 3-year OS rates >80%, prompting many to adopt their use. We evaluated outcomes from a single-center cohort managed in a more traditional fashion. METHODS: We identified patients with MCL evaluated at Weill Cornell Medical Center since 1997, and included those with known date of diagnosis. An online social security database was used to verify survival. RESULTS: We identified 181 patients with MCL, and date of diagnosis could be determined in 111. Three-year OS from diagnosis was 86% [95% confidence interval (CI) 78% to 92%]. Median OS was 7.1 years (95% CI 63-98 months). Adequate information on therapy was available for 75 patients. Only five were treated upfront with (R)-Hyper-CVAD or ASCT while an additional four patients received one of these regimens subsequently. Treatment type had no significant effect on OS. CONCLUSION: Outcomes with standard approaches can yield similar survival to that achieved with more intensive approaches. Biases may account for the perceived superiority of aggressive strategies.


Subject(s)
Biomarkers, Tumor/analysis , Lymphoma, Mantle-Cell/drug therapy , Lymphoma, Mantle-Cell/pathology , Lymphoma, Mantle-Cell/therapy , Stem Cell Transplantation , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal, Murine-Derived , Antineoplastic Agents/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Clinical Trials as Topic , Cohort Studies , Combined Modality Therapy , Cyclophosphamide/administration & dosage , Databases, Factual , Dexamethasone/administration & dosage , Disease-Free Survival , Doxorubicin/administration & dosage , Doxorubicin/analogs & derivatives , Female , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Lymphoma, Mantle-Cell/diagnosis , Lymphoma, Mantle-Cell/mortality , Lymphoma, Mantle-Cell/radiotherapy , Male , Middle Aged , Neoplasm Staging , Prednisone/administration & dosage , Radiotherapy , Regression Analysis , Retrospective Studies , Rituximab , Survival Analysis , Time Factors , Transplantation, Autologous , Treatment Outcome , Vincristine/administration & dosage
7.
Pulm Pharmacol Ther ; 15(2): 103-10, 2002.
Article in English | MEDLINE | ID: mdl-12090783

ABSTRACT

The aims of this study were to investigate the effects of Interleukin-8 (IL-8) and Growth related oncogene-alpha (Gro-alpha) on neutrophil apoptosis and determine the potential for a selective CXCR2 antagonist to inhibit these responses. IL-8 and Gro-alpha both produced dose dependent inhibition of spontaneous human neutrophil apoptosis after 16 hours incubation (59+/-3.5% and 27.5+/-3% respectively; EC50s 2.2+/-1.8 nM, and 0.5+/-0.2 nM respectively). The pro-survival effect of a fixed concentration of agonist (IL-8 or Gro-alpha) on cultured neutrophils was abrogated by a selective CXCR2 antagonist SB272844 (K(D)s 253 nM and 49.9 nM in the presence of IL-8 or Gro-alpha respectively). Our data suggests that the anti-apoptotic effect of Gro-alpha is mediated through CXCR2 as selective CXCR2 blockade with SB272844 can potently abrogate this response. The inhibitory effect of IL-8 may in addition partly be mediated through CXCR1 as SB272844 was less potent in its ability to abrogate the anti-apoptotic effects of IL-8 when this agent was used as an agonist. CXCR2 antagonists may have a therapeutic role in controlling neutrophil-driven inflammation by reducing neutrophil recruitment and restoring neutrophils to the tissue clearance pathway of apoptosis.


Subject(s)
Apoptosis/drug effects , Interleukin-8/physiology , Neutrophils/drug effects , Receptors, Interleukin-8A/antagonists & inhibitors , Receptors, Interleukin-8B/antagonists & inhibitors , Cells, Cultured , Humans
8.
Eur Respir J ; 18(3): 522-9, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11589350

ABSTRACT

Cryptogenic fibrosing alveolitis (CFA) is characterized by increased pulmonary recruitment of peripheral blood neutrophils (PBNs) by interleukin (IL)-8 and other chemotactic mediators. This study investigated whether, in CFA, the PBN motility response is primed by IL-8 and growth-related oncogene (Gro)-alpha, as demonstrated in other neutrophilic inflammatory diseases, and whether the motility response of PBNs to IL-8 and Gro-alpha can be abrogated using a selective antagonist for the neutrophil receptor for IL-8 and Gro-alpha, CXCR2. The percentage of PBNs to undergo shape change (%SC), spontaneously and in response to IL-8 and Gro-alpha, was measured in patients with CFA (n=10) and controls (n=10), and the effect of the CXCR2 antagonist SB272844 studied. Plasma levels of IL-8, and Gro-alpha were measured using an enzyme-linked immunosorbent assay (ELISA). The %SC of unstimulated PBNs and the potency of Gro-alpha and IL-8 to produce neutrophil polarization was greater in CFA than in controls; dose which produces 50% of maximal effect (EC50) of IL-8 was 3.6 +/- 0.7 nM for CFA versus 6.3 +/- 1.0 nM for controls; p<0.05. SB272844 inhibited Gro-alpha induced but not IL-8 induced neutrophil shape change (equilibrium constant (KD) 123 +/- 18 nM). Plasma concentrations of Gro-alpha were increased in patients with CFA. PBNs are spontaneously activated and undergo a greater motility response to IL-8 and Gro-alpha in CFA. Interleukin-8 and growth-related oncogene-alpha, circulating in substimulatory amounts in cryptogenic fibrosing alveolitis, may prime the peripheral blood neutrophils motility response, thus increasing their capacity for migration to the lung. Selective CXCR2 antagonists may be useful to block the Gro-alpha-induced priming response whilst preserving neutrophil functions mediated by CXCR1, the alternative neutrophil receptor for interleukin-8.


Subject(s)
Chemokines, CXC/physiology , Chemotactic Factors/physiology , Growth Substances/physiology , Intercellular Signaling Peptides and Proteins , Interleukin-8/physiology , Lung Diseases, Interstitial/blood , Lung Diseases, Interstitial/physiopathology , Neutrophils/physiology , Aged , Chemokine CXCL1 , Chemotaxis, Leukocyte , Dose-Response Relationship, Drug , Female , Flow Cytometry , Humans , Male , Middle Aged , Receptors, Interleukin-8B/antagonists & inhibitors
9.
J Neurochem ; 79(2): 400-6, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11677268

ABSTRACT

In humans and other vertebrates, reaction of organophosphates with a neuronal membrane protein, neuropathy target esterase (NTE), initiates events which culminate in axonal degeneration. The initiation process appears to involve modification of a property of the protein distinct from its esterase activity, subsequent to formation of a negatively charged adduct with the active site serine residue. Here, we show that membrane patches from liposomes containing NEST, a recombinant hydrophobic polypeptide comprising the esterase domain of human NTE, display a transmembrane ionic conductance with both stable and high-frequency flickering components. An asymmetric current-voltage relationship suggested that ion flow was favoured in one direction relative to the membrane and its associated NEST molecules. Flow of anions was slightly favoured compared with cations. The flickering current formed a much larger proportion of the overall conductance in patches containing wild-type NEST compared with the catalytically inactive S966A mutant form of the protein. The conductance across patches containing NEST, but not those with the S966A mutant, was significantly reduced after adding neuropathic organophosphates to the bathing medium. By contrast, non-neuropathic covalent inhibitors of the catalytic activity of NEST did not reduce NEST-mediated conductance. Future work may establish whether NTE itself mediates an organophosphate-sensitive ion flux across intracellular membranes within intact cells.


Subject(s)
Carboxylic Ester Hydrolases/chemistry , Carboxylic Ester Hydrolases/physiology , Isoflurophate/pharmacology , Organophosphorus Compounds/pharmacology , Carboxylic Ester Hydrolases/antagonists & inhibitors , Catalysis , Electric Conductivity , Humans , Ions , Liposomes , Protein Structure, Tertiary/physiology , Time Factors
10.
Toxicol In Vitro ; 15(4-5): 369-72, 2001.
Article in English | MEDLINE | ID: mdl-11566565

ABSTRACT

The aim of this work was to study the effects of chlorpyrifos (CPF) on the outgrowth of axons by differentiating mouse N2a neuroblastoma cells. This was achieved by morphological, Western blotting and enzymatic analyses of cells induced to differentiate in the presence and absence of CPF added either at the same time (co-differentiation) or 16 h after (post-differentiation) the induction of cell differentiation. The outgrowth of axon-like processes was impaired following 4 or 8 h exposure to CPF in both co- and post-differentiation experiments. Western blotting analysis revealed reduced levels of neurofilament heavy chain (NF-H) following 8 h of exposure but no significant effect at 4 h under both co- and post-differentiation conditions. By contrast, levels of the heat shock protein HSP-70 were raised at both time points, but only in co-differentiation experiments. Neuropathy target esterase (NTE) activity was lower than controls following 4 or 8 h of exposure under co-differentiation conditions, but not under any post-differentiation conditions. The results suggest that the inhibition of axon production and maintenance by CPF in differentiating N2a cells may involve multiple targets, which are different under co- and post-differentiation conditions.


Subject(s)
Chlorpyrifos/toxicity , Insecticides/toxicity , Neurites/drug effects , Neuroblastoma/pathology , Tumor Cells, Cultured/pathology , Animals , Blotting, Western , Carboxylic Ester Hydrolases/metabolism , Cell Differentiation/drug effects , HSP70 Heat-Shock Proteins/metabolism , Mice , Neurites/metabolism , Neuroblastoma/drug therapy , Neuroblastoma/metabolism , Neurofilament Proteins/metabolism , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/metabolism
11.
Aust J Adv Nurs ; 18(4): 23-9, 2001.
Article in English | MEDLINE | ID: mdl-11878547

ABSTRACT

Maternal and child health nurses in two outer urban local government areas in Melbourne, Australia were interviewed about how they facilitated first-time parent groups. Groups were offered to all first time mothers and almost two thirds of mothers joined a group. The groups ran for approximately eight sessions and provided infant-focussed parent education and social contact. Women who joined the groups were followed up 18 months to two years later to determine the degree to which these groups continued to meet on their own accord and the extent to which they had become self-sustaining social networks. The study found a very high level of continuation, suggesting that providing such programs may be an important vehicle for enhancing social support during the transition to parenthood and thus be a useful primary prevention strategy.


Subject(s)
Attitude of Health Personnel , Attitude to Health , Interpersonal Relations , Mothers/education , Mothers/psychology , Self-Help Groups/organization & administration , Social Support , Adult , Curriculum , Female , Follow-Up Studies , Humans , Infant , Infant Care , Infant, Newborn , Nursing Evaluation Research , Parenting , Pediatric Nursing , Pregnancy , Program Evaluation , Surveys and Questionnaires , Victoria
12.
J Biol Chem ; 275(32): 24477-83, 2000 Aug 11.
Article in English | MEDLINE | ID: mdl-10816586

ABSTRACT

Neuropathy target esterase (NTE) is an integral membrane protein in vertebrate neurons and a member of a novel family of putative serine hydrolases. Here we show that NEST, a recombinant polypeptide expressed in Escherichia coli, reacts with an ester substrate and covalent inhibitors in a manner very similar to NTE. NEST comprises residues 727-1216 of human NTE, and site-directed mutagenesis revealed that serine 966 and two aspartate residues, Asp(1086) and Asp(960), are critical for catalysis. The results of mutating the 11 histidines in NEST suggest that NTE does not use a conventional catalytic triad. By reacting NEST with [(3)H]diisopropyl fluorophosphate, Ser(966) was confirmed as the active-site serine, and evidence was obtained that an isopropyl group is transferred from the Ser(966) adduct to an aspartate residue. Detergent was required both for solubilization of NEST from lysates of E. coli and during purification procedures. Catalytic activity was lost in detergent extracts, but was restored when purified NEST was incorporated into dioleoylphosphatidylcholine liposomes. Hydropathy analysis did not indicate the presence of membrane-spanning segments within the NEST sequence. However, biochemical evidence including detergent-phase separation experiments and the resistance of liposome-incorporated NEST to proteolysis indicated that, unlike most eukaryotic serine hydrolases, the catalytic domain of NTE has integral membrane protein properties.


Subject(s)
Aspartic Acid , Carboxylic Ester Hydrolases/chemistry , Carboxylic Ester Hydrolases/metabolism , Serine , Amino Acid Sequence , Amino Acid Substitution , Animals , Binding Sites , Catalytic Domain , Cloning, Molecular , Enzyme Inhibitors/pharmacology , Escherichia coli , Humans , Isoflurophate/metabolism , Isoflurophate/pharmacology , Kinetics , Molecular Sequence Data , Mutagenesis, Site-Directed , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Sequence Alignment , Sequence Homology, Amino Acid
13.
Prog Neurobiol ; 61(1): 61-74, 2000 May.
Article in English | MEDLINE | ID: mdl-10759065

ABSTRACT

Neuropathy target esterase (NTE) is an integral membrane protein in vertebrate neurons. Recent evidence suggests that NTE plays an important role in neural development, possibly via involvement in a signalling pathway between neurons and glial cells. NTE is a member of a novel protein family, represented in organisms from bacteria to man. NTE comprises an N-terminal regulatory domain (with some sequence similarity to cyclic nucleotide-binding proteins) and a C-terminal catalytic domain: the latter has three predicted transmembrane segments and requires membrane-association for activity. In vitro, NTE potently catalyses hydrolysis of phenyl valerate: however, its physiological substrate is likely to be a metabolite of a much longer chain carboxylic acid, possibly associated with cell membranes. NTE was discovered originally as the primary target for those organophosphorus esters (OPs) which cause a delayed neuropathy with degeneration of long axons in peripheral nerves and spinal cord. Paradoxically, NTE's catalytic activity appears redundant in adult vertebrates. Neuropathic OPs react covalently with NTE in a rapid two-step process which not only inhibits catalytic activity but also leaves a negatively-charged OP group attached to the active site serine. The latter event is proposed to induce a toxic gain of function in NTE. OP-modified NTE somehow engenders a "chemical transection of the axon". In turn, this leads to calcium entry, elevation of axonal calpain activity and Wallerian-type degeneration. The net damage to peripheral nerve axons is a balance between ongoing degenerative and repair processes: the latter involve serine hydrolases which can be inhibited by the same OPs used to modify NTE.


Subject(s)
Carboxylic Ester Hydrolases/metabolism , Nerve Degeneration/metabolism , Nervous System/enzymology , Nervous System/physiopathology , Peripheral Nervous System Diseases/metabolism , Peripheral Nervous System Diseases/physiopathology , Animals , Humans
14.
Mech Dev ; 90(2): 279-82, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10640712

ABSTRACT

The Drosophila neurodegeneration gene swiss-cheese encodes a neuronal protein apparently involved in glia-neuron interaction and is homologous to human NTE, the molecular target of organophosphate-induced neuropathy. The isolated Msws/NTE gene is 96% identical to NTE. During development the Msws transcript is expressed in the embryonic respiratory system, different epithelial structures and strongly in the spinal ganglia. Postnatally, Msws mRNA is expressed in all brain areas, with an increasingly restrictive pattern. In adult mice expression is most prominent in Purkinje cells, granule cells and pyramidal neurons of the hippocampus and some large neurons in the medulla oblongata, nucleus dentatus and pons.


Subject(s)
Carboxylic Ester Hydrolases/genetics , Drosophila Proteins , Nerve Tissue Proteins/genetics , Amino Acid Sequence , Animals , Base Sequence , Brain/metabolism , Brain/pathology , Cloning, Molecular , DNA, Complementary , Gene Expression , Humans , Mice , Molecular Sequence Data
16.
Biochem J ; 344 Pt 3: 625-31, 1999 Dec 15.
Article in English | MEDLINE | ID: mdl-10585848

ABSTRACT

Neuropathy target esterase (NTE) is an integral membrane protein present in all neurons and in some non-neural-cell types of vertebrates. Recent data indicate that NTE is involved in a cell-signalling pathway controlling interactions between neurons and accessory glial cells in the developing nervous system. NTE has serine esterase activity and efficiently catalyses the hydrolysis of phenyl valerate (PV) in vitro, but its physiological substrate is unknown. By sequence analysis NTE has been found to be related neither to the major serine esterase family, which includes acetylcholinesterase, nor to any other known serine hydrolases. NTE comprises at least two functional domains: an N-terminal putative regulatory domain and a C-terminal effector domain which contains the esterase activity and is, in part, conserved in proteins found in bacteria, yeast, nematodes and insects. NTE's effector domain contains three predicted transmembrane segments, and the active-site serine residue lies at the centre of one of these segments. The isolated recombinant domain shows PV hydrolase activity only when incorporated into phospholipid liposomes. NTE's esterase activity appears to be largely redundant in adult vertebrates, but organophosphates which react with NTE in vivo initiate unknown events which lead, after a delay of 1-3 weeks, to a neuropathy with degeneration of long axons. These neuropathic organophosphates leave a negatively charged group covalently attached to the active-site serine residue, and it is suggested that this may cause a toxic gain of function in NTE.


Subject(s)
Carboxylic Ester Hydrolases/physiology , Amino Acid Sequence , Animals , Binding Sites , Carboxylic Ester Hydrolases/biosynthesis , Carboxylic Ester Hydrolases/chemistry , Cloning, Molecular , Humans , Membrane Proteins/chemistry , Molecular Sequence Data , Nervous System Diseases/chemically induced , Nervous System Diseases/enzymology , Neurons/enzymology , Species Specificity , Tritolyl Phosphates/toxicity , Valerates/metabolism
17.
J Pathol ; 189(2): 161-8, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10547569

ABSTRACT

Enhanced expression of the type IV collagenases MMP-2 and MMP-9, or lack of their inhibitors TIMP-1 and TIMP-2, has been associated with tumour invasion and metastatic potential in several experimental models. Regulation of enzyme activity is clearly a key step in tumour invasion, and recently a potent activator of MMP-2, the membrane-associated MT1-MMP, has been described and characterized. Using an immunohistochemical approach, this study has examined the expression and distribution of the type IV collagenases, their inhibitors, and the activator MT1-MMP, in a series of 79 infiltrating ductal carcinomas (IDCs), 8 tubular carcinomas, and 27 infiltrating lobular carcinomas (ILCs). MMP-2 and MT1-MMP were expressed in more than 90 per cent of all carcinomas, with predominantly stromal and tumour cell cytoplasmic staining. However, reactivity localized on tumour cell membranes was recorded for MMP-2 in 34 per cent of cases with a monoclonal antibody and 55 per cent of cases with a polyclonal antibody, and for MT1-MMP in 68 per cent of tumours. In each case, this pattern of staining was significantly associated with the presence of lymph node metastasis (p=0.001, p=0. 008, and p=0.1, respectively). Both tumour cell and stromal staining was observed for TIMP-2, but there was no correlation with metastatic status. The 92 kD gelatinase MMP-9 was expressed by 68 per cent of carcinomas, either in the stromal compartment or by tumour cells. There was a highly significant correlation between the expression pattern of MMP-9 and tumour type, with ILCs displaying greater frequency and more homogeneous cytoplasmic staining than IDCs (p=0.0004). Staining for TIMP-1 was seen in the stroma and also in relation to small blood vessels, with more than 90 per cent of tumours showing this staining pattern using a polyclonal antibody. This study indicates distinct patterns of expression for different MMPs and demonstrates the potential importance of the MMP-2/MT1-MMP system in breast tumour progression. The association of MMP-9 with the infiltrating lobular phenotype may reveal novel mechanisms of control for this metalloproteinase.


Subject(s)
Breast Neoplasms/enzymology , Carcinoma, Lobular/enzymology , Metalloendopeptidases/metabolism , Neoplasm Proteins/metabolism , Tissue Inhibitor of Metalloproteinases/metabolism , Analysis of Variance , Breast/enzymology , Carcinoma, Ductal, Breast/enzymology , Female , Humans , Immunoenzyme Techniques , Lymphatic Metastasis , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/metabolism , Matrix Metalloproteinases, Membrane-Associated , Tissue Inhibitor of Metalloproteinase-1/metabolism , Tissue Inhibitor of Metalloproteinase-2/metabolism
18.
Surgery ; 126(2): 231-8, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10455889

ABSTRACT

BACKGROUND: Mechanisms of cardiac dysfunction during endotoxemia are multiple and their targets uncertain. This study tested the hypothesis that endotoxin (LPS) induces abnormal calcium-activated contractile force in the heart. METHODS: Adult rabbits were given LPS intravenously; 2 hours later hearts were studied in the Langendorff mode. Measurements included peak developed pressure (PDP), myocardial oxygen consumption (MVO2), high-energy phosphates by 31P-NMR, and beat-to-beat intracellular calcium (Cai) by fluorescence spectroscopy. Myofibrillar calcium sensitivity was assessed from the relationship of PDP to Cai and the rate of diastolic Cai removal (tau Ca) was quantified. RESULTS: Force-calcium relationships were markedly depressed in LPS hearts despite increased Cai. MVO2 was increased in parallel with increased Cai. Taken together, these data denote myofilament calcium insensitivity and mechanical inefficiency. tau Ca was markedly prolonged in LPS hearts, indicating impaired calcium reuptake and/or extrusion. High-energy phosphates and intracellular pH were unaffected by LPS; however, inorganic phosphate (Pi) was significantly increased. Dobutamine further increased Cai and MVO2 in LPS hearts without significantly improving calcium-activated force. Pyruvate, an inotrope that reduces Pi, significantly improved contractility in LPS hearts. CONCLUSIONS: Endotoxemia rapidly induced futile calcium cycling and reduced myofibrillar calcium sensitivity. This state was resistant to beta-agonist inotropic stimulation; inotropes that normalize the calcium-force relationship may be more effective.


Subject(s)
Actin Cytoskeleton/metabolism , Calcium/metabolism , Endotoxemia/metabolism , Myocardium/metabolism , Adenosine Triphosphate/metabolism , Animals , Dobutamine/pharmacology , Energy Metabolism , Lipopolysaccharides/toxicity , Myocardial Contraction/drug effects , Oxygen Consumption/drug effects , Pyruvic Acid/pharmacology , Rabbits
19.
Eur Respir J ; 13(6): 1380-5, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10445615

ABSTRACT

It was hypothesized that there would be an upregulation of systemic neutrophil CD11b expression in pneumonia. Expression of CD11b and concentrations of soluble intercellular adhesion molecule (ICAM)-1 and E-selectin were evaluated as potential surrogate markers of the severity of pneumonia. Possible age-related immunosenescence in relation to neutrophil CD11b expression in elderly patients with pneumonia was examined for. In patients with community-acquired pneumonia (n = 36) neutrophil CD11b expression was measured by flow cytometry and soluble ICAM-1 and E-selectin concentrations by enzyme-linked immunosorbent assay. An upregulation of neutrophil CD11b expression and increased soluble adhesion molecule concentrations on admission were confirmed, but the concentrations did not correlate with patient Acute Physiology and Chronic Health Evaluation II scores. Neutrophil CD11b expression was similar between elderly (age range 70-100 yrs) and younger (age range 18-70 yrs) patients with pneumonia. In conclusion, there is evidence of neutrophil and endothelial cell activation in pneumonia as indicated by upregulation of CD11b and increased soluble intercellular adhesion molecule and E-selectin, however, they do not appear to be good surrogate markers of severity of infection. Advanced age does not influence adhesion molecule expression in pneumonia.


Subject(s)
E-Selectin/metabolism , Intercellular Adhesion Molecule-1/metabolism , Macrophage-1 Antigen/metabolism , Neutrophils/metabolism , Pneumonia, Bacterial/metabolism , APACHE , Adolescent , Adult , Aged , Aged, 80 and over , Aging/immunology , Community-Acquired Infections/metabolism , Enzyme-Linked Immunosorbent Assay , Flow Cytometry , Humans , Middle Aged , Up-Regulation
20.
Chem Biol Interact ; 119-120: 513-7, 1999 May 14.
Article in English | MEDLINE | ID: mdl-10421490

ABSTRACT

Covalent modification of NTE, a neuronal protein with serine esterase activity, by certain organophosphates (OP) initiates degeneration of long axons in the peripheral and central nervous system. Simple inhibition of NTE esterase activity does not initiate neuropathy; the latter requires aging of the OP bound to the catalytic serine residue so that a negatively-charged species is left attached to the active site. This may indicate that a non-esterase function of NTE is important for axonal maintenance. We have recently cloned NTE and shown that it is unrelated to any known serine hydrolases but contains a novel C-terminal domain which is conserved from bacteria to man. Furthermore, the catalytic serine is located within this domain at the centre of a helical hydrophobic segment of the polypeptide's secondary structure. The integrity of NTE would be severely compromised by the presence of a negatively-charged organophosphate moiety at this site. Implications for possible higher-order structures and functions for NTE are discussed.


Subject(s)
Carboxylic Ester Hydrolases/genetics , Carboxylic Ester Hydrolases/isolation & purification , Binding Sites , Brain/enzymology , Carboxylic Ester Hydrolases/metabolism , Catalysis , Cloning, Molecular , Humans , Serine/genetics , Serine/metabolism
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