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1.
Sociol Health Illn ; 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38251766

ABSTRACT

Diagnostic encounters can be seen as complex socio-material processes. Drawing on the new materialist ideas of Barad, we studied how an innovative technology became part of the intra-actions between different human and non-human materialities in a cervical cancer diagnostic process. While researching the development of a technology intended to improve cervical cancer detection, we carried out a series of observations of diagnostic encounters involving clinicians, patients and the device in a hospital. The intra-actions between the different materialities had rhythmic properties, repeated activities and timings that varied in intensity, for example, movements, exchanged looks, and talk that helped co-produce the diagnosis and maintain consent. Sadly, the device interfered with the rhythms, undermining the clinicians' desire to adopt it, despite it being more accurate at diagnosing ill health than previous assistive technologies. Studying rhythms as part of diagnostic encounters could help with the design and subsequent integration of novel technologies in healthcare, because they encompass relationships created by human and non-human materialities. Importantly, highlighting the role of rhythms contributes another way diagnostic encounters are co-produced between clinicians and patients, and how they can be disrupted, improving the understanding of how consent is maintained or lost.

2.
PLoS One ; 14(1): e0210888, 2019.
Article in English | MEDLINE | ID: mdl-30682074

ABSTRACT

Deep subcortical lesions (DSCL) of the brain, are present in ~60% of the ageing population, and are linked to cognitive decline and depression. DSCL are associated with demyelination, blood brain barrier (BBB) dysfunction, and microgliosis. Microglia are the main immune cell of the brain. Under physiological conditions microglia have a ramified morphology, and react to pathology with a change to a more rounded morphology as well as showing protein expression alterations. This study builds on previous characterisations of DSCL and radiologically 'normal-appearing' white matter (NAWM) by performing a detailed characterisation of a range of microglial markers in addition to markers of vascular integrity. The Cognitive Function and Ageing Study (CFAS) provided control white matter (WM), NAWM and DSCL human post mortem tissue for immunohistochemistry using microglial markers (Iba-1, CD68 and MHCII), a vascular basement membrane marker (collagen IV) and markers of BBB integrity (fibrinogen and aquaporin 4). The immunoreactive profile of CD68 increased in a stepwise manner from control WM to NAWM to DSCL. This correlated with a shift from small, ramified cells, to larger, more rounded microglia. While there was greater Iba-1 immunoreactivity in NAWM compared to controls, in DSCL, Iba-1 levels were reduced to control levels. A prominent feature of these DSCL was a population of Iba-1-/CD68+ microglia. There were increases in collagen IV, but no change in BBB integrity. Overall the study shows significant differences in the immunoreactive profile of microglial markers. Whether this is a cause or effect of lesion development remains to be elucidated. Identifying microglia subpopulations based on their morphology and molecular markers may ultimately help decipher their function and role in neurodegeneration. Furthermore, this study demonstrates that Iba-1 is not a pan-microglial marker, and that a combination of several microglial markers is required to fully characterise the microglial phenotype.


Subject(s)
Aging/metabolism , Aging/pathology , Antigens, CD/metabolism , Antigens, Differentiation, Myelomonocytic/metabolism , DNA-Binding Proteins/metabolism , Microglia/metabolism , Microglia/pathology , White Matter/metabolism , White Matter/pathology , Aging/immunology , Biomarkers/metabolism , Blood-Brain Barrier/metabolism , Blood-Brain Barrier/pathology , Calcium-Binding Proteins , Cell Shape , Cognitive Dysfunction/metabolism , Cognitive Dysfunction/pathology , Histocompatibility Antigens Class II/metabolism , Humans , Immunohistochemistry , Microfilament Proteins , Microglia/immunology , Myelin Sheath/metabolism , White Matter/immunology
3.
Brain ; 135(Pt 3): 751-64, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22366792

ABSTRACT

Intronic expansion of the GGGGCC hexanucleotide repeat within the C9ORF72 gene causes frontotemporal dementia and amyotrophic lateral sclerosis/motor neuron disease in both familial and sporadic cases. Initial reports indicate that this variant within the frontotemporal dementia/amyotrophic lateral sclerosis spectrum is associated with transactive response DNA binding protein (TDP-43) proteinopathy. The amyotrophic lateral sclerosis/motor neuron disease phenotype is not yet well characterized. We report the clinical and pathological phenotypes associated with pathogenic C9ORF72 mutations in a cohort of 563 cases from Northern England, including 63 with a family history of amyotrophic lateral sclerosis. One hundred and fifty-eight cases from the cohort (21 familial, 137 sporadic) were post-mortem brain and spinal cord donors. We screened DNA for the C9ORF72 mutation, reviewed clinical case histories and undertook pathological evaluation of brain and spinal cord. Control DNA samples (n = 361) from the same population were also screened. The C9ORF72 intronic expansion was present in 62 cases [11% of the cohort; 27/63 (43%) familial, 35/500 (7%) cases with sporadic amyotrophic lateral sclerosis/motor neuron disease]. Disease duration was significantly shorter in cases with C9ORF72-related amyotrophic lateral sclerosis (30.5 months) compared with non-C9ORF72 amyotrophic lateral sclerosis/motor neuron disease (36.3 months, P < 0.05). C9ORF72 cases included both limb and bulbar onset disease and all cases showed combined upper and lower motor neuron degeneration (amyotrophic lateral sclerosis). Thus, clinically, C9ORF72 cases show the features of a relatively rapidly progressive, but otherwise typical, variant of amyotrophic lateral sclerosis associated with both familial and sporadic presentations. Dementia was present in the patient or a close family member in 22/62 cases with C9ORF72 mutation (35%) based on diagnoses established from retrospective clinical case note review that may underestimate significant cognitive changes in late disease. All the C9ORF72 mutation cases showed classical amyotrophic lateral sclerosis pathology with TDP-43 inclusions in spinal motor neurons. Neuronal cytoplasmic inclusions and glial inclusions positive for p62 immunostaining in non-motor regions were strongly over-represented in the C9ORF72 cases. Extra-motor pathology in the frontal cortex (P < 0.0005) and the hippocampal CA4 subfield neurons (P < 0.0005) discriminated C9ORF72 cases strongly from the rest of the cohort. Inclusions in CA4 neurons were not present in non-C9ORF72 cases, indicating that this pathology predicts mutation status.


Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/pathology , Proteins/genetics , Adult , Age of Onset , Aged , Amyotrophic Lateral Sclerosis/psychology , Biological Specimen Banks , Brain/pathology , C9orf72 Protein , Cognition Disorders/etiology , Cohort Studies , DNA/genetics , DNA Repeat Expansion , Dentate Gyrus/pathology , England , Female , Humans , Immunohistochemistry , Inclusion Bodies/pathology , Male , Middle Aged , Neurons/pathology , Phenotype , Real-Time Polymerase Chain Reaction , Spinal Cord/pathology
4.
Neurobiol Aging ; 32(10): 1795-807, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21705112

ABSTRACT

Astrocytes contribute to a variety of functions in the brain, including homeostasis, synapse formation, plasticity, and metabolism. Astrocyte dysfunction may disrupt their normal role, including neuronal support, thereby contributing to neurodegenerative pathologies, including Alzheimer's disease (AD). To understand the role of astrocytes in the pathogenesis of age-related disorders, we isolated astrocytes by laser capture microdissection, using glial fibrillary acidic protein (GFAP) as a marker, and characterized the astrocyte transcriptome at different Braak neurofibrillary tangle stages in postmortem temporal cortex samples derived from the Medical Research Council Cognitive Function and Ageing Study (MRC CFAS) cohort, using microarray analysis. The largest number of significant, differentially expressed genes were identified when the expression profile of astrocytes from isocortical stages of neurofibrillary tangle pathology (Braak stages V-VI) were compared with entorhinal stages (Braak stages I-II). Dysregulation of genes associated with the actin cytoskeleton, proliferation, apoptosis, and ubiquitin-mediated proteolysis occurred at low Braak stages, while altered regulation of intracellular signaling pathways, including insulin, phosphatidylinositol 3-kinase (PI3K)/Akt, and mitogen-activated protein kinase (MAPK) pathways were primarily associated with high levels of Alzheimer-type pathology, and occurred at lower Braak stages in individuals with the APOEε4 allele. Our findings implicate astrocyte dysfunction in the pathogenesis of neurodegenerative pathology in the aging brain, and provide a basis for future candidate studies based on specific pathways.


Subject(s)
Aging/pathology , Apolipoproteins E/genetics , Astrocytes/metabolism , Gene Expression Regulation/genetics , Temporal Lobe/pathology , Transcriptome/physiology , Actins/metabolism , Aged , Aged, 80 and over , Astrocytes/pathology , Female , Genotype , Glial Fibrillary Acidic Protein/metabolism , Humans , Male , Microarray Analysis/methods , Microdissection/methods , Postmortem Changes , Reproducibility of Results , Signal Transduction/genetics
5.
Neurosci Lett ; 486(3): 246-51, 2010 Dec 17.
Article in English | MEDLINE | ID: mdl-20887772

ABSTRACT

White matter lesions (WML) are associated with dementia and are common in brain ageing. In order to determine whether alteration of the blood-brain barrier (BBB) may contribute to the pathogenesis of WML we assessed albumin leakage and expression of the tight junction (TJ) proteins claudin-5 (Cln-5), zona occludin-1 (ZO-1) and occludin in cases derived from the Medical Research Council Cognitive Function and Ageing Study. Albumin extravasation was widespread in the ageing brain and enhanced in WML, suggesting dysfunction of the BBB may contribute to the pathogenesis of WML. This was not accompanied by significant changes in the endothelial expression of TJ proteins. However, ZO-1 and occludin were expressed by glial cells throughout the parenchyma of both control white matter and WML, suggesting these TJ proteins may have other functions in the brain.


Subject(s)
Aging/pathology , Blood-Brain Barrier/physiopathology , Cerebral Cortex/blood supply , Cerebral Cortex/physiopathology , Nerve Fibers, Myelinated/pathology , Aged , Aged, 80 and over , Aging/physiology , Capillaries/pathology , Capillaries/physiopathology , Cerebral Arteries/pathology , Cerebral Arteries/physiopathology , Cerebral Cortex/pathology , Female , Humans , Male , Tight Junctions/pathology
6.
J Neuropathol Exp Neurol ; 65(1): 26-36, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16410746

ABSTRACT

Vascular endothelial growth factor (VEGF) prolongs survival in the mutant SOD1 transgenic mouse model of amyotrophic lateral sclerosis (ALS), whereas dysregulation of VEGF through deletion of its hypoxia-regulatory element causes motor neuron degeneration in mice. We investigated the expression of VEGF and its major agonist receptors in the normal central nervous system and in patients with ALS. Immunohistochemistry demonstrated similar expression patterns of VEGF and VEGF receptor 2 (VEGFR2) in the spinal cord with finely punctate staining of the neuropil and strong expression in anterior horn cells (AHCs). Granular staining on the surface of some AHCs, similar to that seen with synaptic markers, suggested synaptic labeling. VEGFR2 staining was reduced in the neuropil of ALS cases (p=0.018) associated with a reduction of synaptophysin but not SNAP25 expression. A greater proportion of AHCs in ALS cases showed low expression of VEGF (p=0.006) and VEGFR2 (p=0.009) compared with controls. Expression of VEGF and VEGFR2 was confirmed by Western blotting and quantitative reverse transcriptase-polymerase chain reaction (QPCR). The similar expression patterns of VEGF and VEGFR2 suggests autocrine/paracrine effects on spinal motor neurons, and the reduction in their expression seen in ALS cases would support the hypothesis that, as in mouse models of the disease, reduced VEGF signaling may play a role in the pathogenesis of ALS.


Subject(s)
Amyotrophic Lateral Sclerosis/metabolism , Central Nervous System/metabolism , Gene Expression/physiology , Vascular Endothelial Growth Factor A/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolism , Aged , Aged, 80 and over , Blotting, Western/methods , Female , Humans , Immunohistochemistry/methods , Male , Middle Aged , Postmortem Changes , Reverse Transcriptase Polymerase Chain Reaction/methods , Statistics, Nonparametric , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor Receptor-2/genetics
7.
J Physiol ; 571(Pt 1): 147-63, 2006 Feb 15.
Article in English | MEDLINE | ID: mdl-16357015

ABSTRACT

The mechanisms by which prostaglandin F(2alpha) (PGF(2alpha)) increases intracellular Ca2+ concentration [Ca2+]i in vascular smooth muscle remain unclear. We examined the role of store-, receptor- and voltage-operated Ca2+ influx pathways in rat intrapulmonary arteries (IPA) loaded with Fura PE-3. Low concentrations (0.01-1 microM) of PGF(2alpha) caused a transient followed by a plateau rise in [Ca2+]i. Both responses became maximal at 0.1 microM PGF(2alpha). At higher concentrations of PGF(2alpha), a further slower rise in [Ca2+]i was superimposed on the plateau. The [Ca2+]i response to 0.1 microM PGF(2alpha) was mimicked by the FP receptor agonist fluprostenol, whilst the effect of 10 microM PGF(2alpha) was mimicked by the TP receptor agonist U-46619. The plateau rise in [Ca2+]i in response to 0.1 microM PGF(2alpha) was insensitive to diltiazem, and was abolished in Ca2+-free physiological salt solution, and by pretreatment with La3+, 2-APB, thapsigargin or U-73122. The rises in [Ca2+]i in response to 10 microM PGF(2alpha) and 0.01 microM U-46619 were partially inhibited by diltiazem. The diltiazem-resistant components of both of these responses were inhibited by 2-APB and La3+ to an extent which was significantly less than that seen for the response to 0.1 microM PGF(2alpha), and were also much less sensitive to U-73122. The U-46619 response was also relatively insensitive to thapsigargin. When Ca2+ was replaced with Sr2+, the sustained increase in the Fura PE-3 signal to 0.1 microM PGF(2alpha) was abolished, whereas 10 microM PGF(2alpha) and 0.05 microM U-46619 still caused substantial increases. These results suggest that low concentrations of PGF(2alpha) act via FP receptors to cause IP3-dependent Ca2+ release and store operated Ca2+ entry (SOCE). U-46619 and 10-100 microM PGF(2alpha) cause a TP receptor-mediated Ca2+ influx involving both L-type Ca2+ channels and a receptor operated pathway, which differs from SOCE in its susceptibility to La3+, 2-APB and thapsigargin, does not require phospholipase C activation, and is Sr2+ permeable.


Subject(s)
Calcium/analysis , Calcium/metabolism , Dinoprost/pharmacology , Pulmonary Artery/metabolism , 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid/pharmacology , Animals , Boron Compounds/pharmacology , Calcium Channels, L-Type/physiology , Cardiovascular Agents/pharmacology , Diltiazem/pharmacology , Inositol 1,4,5-Trisphosphate/physiology , Male , Muscle, Smooth, Vascular/drug effects , Muscle, Smooth, Vascular/physiology , Pulmonary Artery/chemistry , Rats , Rats, Wistar , Receptors, Prostaglandin/drug effects , Receptors, Prostaglandin/physiology , Receptors, Thromboxane/drug effects , Receptors, Thromboxane/physiology , Signal Transduction/physiology , Type C Phospholipases/pharmacology , Vasoconstriction/drug effects , Vasoconstrictor Agents/pharmacology
8.
Neurosci Lett ; 383(1-2): 33-8, 2005.
Article in English | MEDLINE | ID: mdl-15936508

ABSTRACT

Cell-cycle mechanisms may be aberrantly reactivated in the ageing brain and associated with the development of pathology, including Alzheimer's disease. Activation of cell-cycle mechanisms in glia has, however, been little studied. Our aim was to determine whether expression of a marker for chromosomal replication licensing, Mcm2, occurs in glia of the ageing hippocampus, and to compare its expression to that of Ki67 and PCNA. Blocks of hippocampus were obtained from 19 elderly brains derived from the MRC-CFAS neuropathology cohort, which included a spectrum of Alzheimer-type pathology, semi-quantified using the Braak scoring system for neurofibrillary tangles. Mcm2, PCNA and Ki67 were detected immunohistochemically. Expression of Mcm2, Ki67 and PCNA was observed in glial cells and neurons, with a trend to increased expression in association with higher burdens of Alzheimer-type pathology. Mcm2 expression in glial cells showed a significant linear trend across Braak stages (P = 0.043). This study demonstrates that grey and white matter glial cells show expression of cell-cycle markers in the ageing brain and that re-licensing for chromosomal replication is a component of the mechanisms activated. A quantitative relationship to the burden of Alzheimer-type pathology suggests that cell-cycle re-entry in glial cells may be important in the pathogenesis of age-related neurodegeneration.


Subject(s)
Aging/metabolism , Alzheimer Disease/pathology , Cell Cycle Proteins/metabolism , Ki-67 Antigen/metabolism , Neuroglia/metabolism , Nuclear Proteins/metabolism , Proliferating Cell Nuclear Antigen/metabolism , Aged , Aged, 80 and over , Cell Count/methods , Gene Expression , Hippocampus/metabolism , Hippocampus/pathology , Humans , Immunohistochemistry/methods , Minichromosome Maintenance Complex Component 2 , Neuroglia/pathology , Statistics, Nonparametric
9.
Fertil Steril ; 83(1): 78-85, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15652891

ABSTRACT

OBJECTIVE: To determine the expression of inhibin betaA and betaB subunits and follistatin and the ability of human epididymal epithelium to synthesize these molecules. DESIGN: The main aim of this study was to investigate the expression of inhibin alpha, betaA, and betaB-subunits and follistatin in human epididymis with immunohistochemistry, in situ hybridization, and Western blotting in adult life. SETTING: Academic university hospital. PATIENT(S): Epididymes were obtained from 10 men undergoing routine vasectomy or surgery for benign disease at the Royal Hallamshire Hospital, Sheffield, United Kingdom. MAIN OUTCOME MEASURE(S): Immunoexpression of activin betaA and betaB subunits and follistatin proteins and mRNA in human caput and cauda epididymis. RESULT(S): Positive immunoexpression for activin betaA and betaB subunits and follistatin were detected in different parts of the epididymis epithelium. Western blotting under a reducing condition detected a 28-kd band (possibly corresponding to the activin dimer). In situ hybridization indicated positive mRNA localization signal in both caput and cauda epididymal epithelium. CONCLUSION(S): Activins betaA and betaB subunits, but not inhibin alpha subunit, were detected in epididymal epithelium. These finding suggest that activins might have a role in the processes of sperm maturation and sperm fertilizing capability during transit and storage.


Subject(s)
Epididymis/chemistry , Follistatin/analysis , Inhibin-beta Subunits/analysis , Inhibins/analysis , Adult , Blotting, Western , Follistatin/genetics , Humans , Immunohistochemistry , In Situ Hybridization , Inhibin-beta Subunits/genetics , Inhibins/genetics , Male , Middle Aged , RNA, Messenger/analysis
10.
Br J Pharmacol ; 140(8): 1442-50, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14623766

ABSTRACT

The effect of the Cl- channel blockers niflumic acid (NFA), 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), and anthracene-9-carboxylic acid (A-9-C), on Ca2+ signalling in rat pulmonary artery smooth muscle cells was examined. Intracellular Ca2+ concentration ([Ca2+]i) was monitored with either fura-2 or fluo-4, and caffeine was used to activate the ryanodine receptor, thereby releasing Ca2+ from the sarcoplasmic reticulum (SR). NFA and NPPB significantly increased basal [Ca2+]i and attenuated the caffeine-induced increase in [Ca2+]i. These Cl- channel blockers also increased the half-time (t1/2) to peak for the caffeine-induced [Ca2+]i transient, and slowed the removal of Ca2+ from the cytosol following application of caffeine. Since DIDS and A-9-C were found to adversely affect fura-2 fluorescence, fluo-4 was used to monitor intracellular Ca2+ in studies involving these Cl- channel blockers. Both DIDS and A-9-C increased basal fluo-4 fluorescence, indicating an increase in intracellular Ca2+, and while DIDS had no significant effect on the t1/2 to peak for the caffeine-induced Ca2+ transient, it was significantly increased by A-9-C. In the absence of extracellular Ca2+, NFA significantly increased basal [Ca2+]i, suggesting that the release of Ca2+ from an intracellular store was responsible for the observed effect. Depleting the SR with the combination of caffeine and cyclopiazonic acid prevented the increase in basal [Ca2+]i induced by NFA. Additionally, incubating the cells with ryanodine also prevented the increase in basal [Ca2+]i induced by NFA. These data show that Cl- channel blockers have marked effects on Ca2+ signalling in pulmonary artery smooth muscle cells. Furthermore, examination of the NFA-induced increase in [Ca2+]i indicates that it is likely due to Ca2+ release from an intracellular store, most probably the SR.


Subject(s)
Calcium/metabolism , Chloride Channels/antagonists & inhibitors , Muscle, Smooth, Vascular/metabolism , Niflumic Acid/pharmacology , Pulmonary Artery/metabolism , 4,4'-Diisothiocyanostilbene-2,2'-Disulfonic Acid/pharmacology , Animals , Anthracenes/pharmacology , Caffeine/pharmacology , Calcium Signaling/drug effects , Cells, Cultured , Chloride Channels/physiology , Male , Muscle, Smooth, Vascular/cytology , Nitrobenzoates/pharmacology , Pulmonary Artery/cytology , Rats , Rats, Sprague-Dawley , Ryanodine/pharmacology , Sarcoplasmic Reticulum/drug effects , Sarcoplasmic Reticulum/metabolism
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