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1.
Psychol Med ; 47(9): 1624-1636, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28183377

ABSTRACT

BACKGROUND: Functional neurological disorders (FNDs), also known as conversion disorder, are unexplained neurological symptoms unrelated to a neurological cause. The disorder is common, yet poorly understood. The symptoms are experienced as involuntary but have similarities to voluntary processes. Here we studied intention awareness in FND. METHOD: A total of 26 FND patients and 25 healthy volunteers participated in this functional magnetic resonance study using Libet's clock. RESULTS: FND is characterized by delayed awareness of the intention to move relative to the movement itself. The reporting of intention was more precise, suggesting that these findings are reliable and unrelated to non-specific attentional deficits. That these findings were more prominent with aberrant positive functional movement symptoms rather than negative symptoms may be relevant to impairments in timing for an inhibitory veto process. Attention towards intention relative to movement was associated with lower right inferior parietal cortex activity in FND, a region early in the processing of intention. During rest, aberrant functional connectivity was observed with the right inferior parietal cortex and other motor intention regions. CONCLUSIONS: The results converge with observations of low inferior parietal activity comparing involuntary with voluntary movement in FND, emphasizing core deficiencies in intention. Heightened precision of this impaired intention is consistent with Bayesian theories of impaired top-down priors that might influence the sense of involuntariness. A primary impairment in voluntary motor intention at an early processing stage might explain clinical observations of slowed effortful voluntary movement, heightened self-directed attention and underlie functional movements. These findings further suggest novel therapeutic targets.


Subject(s)
Attention/physiology , Awareness/physiology , Cerebral Cortex/physiopathology , Conversion Disorder/physiopathology , Functional Neuroimaging/methods , Intention , Motor Activity/physiology , Psychomotor Performance/physiology , Adult , Cerebral Cortex/diagnostic imaging , Conversion Disorder/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged
2.
Psychol Med ; 47(4): 585-596, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27804899

ABSTRACT

BACKGROUND: The efficient organization and communication of brain networks underlie cognitive processing and their disruption can lead to pathological behaviours. Few studies have focused on whole-brain networks in obesity and binge eating disorder (BED). Here we used multi-echo resting-state functional magnetic resonance imaging (rsfMRI) along with a data-driven graph theory approach to assess brain network characteristics in obesity and BED. METHOD: Multi-echo rsfMRI scans were collected from 40 obese subjects (including 20 BED patients) and 40 healthy controls and denoised using multi-echo independent component analysis (ME-ICA). We constructed a whole-brain functional connectivity matrix with normalized correlation coefficients between regional mean blood oxygenation level-dependent (BOLD) signals from 90 brain regions in the Automated Anatomical Labeling atlas. We computed global and regional network properties in the binarized connectivity matrices with an edge density of 5%-25%. We also verified our findings using a separate parcellation, the Harvard-Oxford atlas parcellated into 470 regions. RESULTS: Obese subjects exhibited significantly reduced global and local network efficiency as well as decreased modularity compared with healthy controls, showing disruption in small-world and modular network structures. In regional metrics, the putamen, pallidum and thalamus exhibited significantly decreased nodal degree and efficiency in obese subjects. Obese subjects also showed decreased connectivity of cortico-striatal/cortico-thalamic networks associated with putaminal and cortical motor regions. These findings were significant with ME-ICA with limited group differences observed with conventional denoising or single-echo analysis. CONCLUSIONS: Using this data-driven analysis of multi-echo rsfMRI data, we found disruption in global network properties and motor cortico-striatal networks in obesity consistent with habit formation theories. Our findings highlight the role of network properties in pathological food misuse as possible biomarkers and therapeutic targets.


Subject(s)
Binge-Eating Disorder/physiopathology , Cerebral Cortex/physiopathology , Connectome/methods , Obesity/physiopathology , Putamen/physiopathology , Adult , Binge-Eating Disorder/diagnostic imaging , Cerebral Cortex/diagnostic imaging , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Obesity/diagnostic imaging , Putamen/diagnostic imaging
3.
Curr Behav Neurosci Rep ; 3: 49-57, 2016.
Article in English | MEDLINE | ID: mdl-27034915

ABSTRACT

Cognitive constructs provide conceptual frameworks for transpathological characterization and improved phenotyping of apparently disparate psychiatric groups. This dimensional approach can be applied to the examination of individuals with behavioral addictions, for example, towards gambling, video-games, the internet, food, and sex, allowing operationalization of core deficits. We use this approach to review constructs such as impulsivity, compulsivity, and attention regulation, which may be most relevant, applicable, and successful for the understanding and subsequent treatment of the addictions.

4.
Transl Psychiatry ; 5: e670, 2015 Nov 03.
Article in English | MEDLINE | ID: mdl-26529423

ABSTRACT

Our decisions are based on parallel and competing systems of goal-directed and habitual learning, systems which can be impaired in pathological behaviours. Here we focus on the influence of motivation and compare reward and loss outcomes in subjects with obsessive-compulsive disorder (OCD) on model-based goal-directed and model-free habitual behaviours using the two-step task. We further investigate the relationship with acquisition learning using a one-step probabilistic learning task. Forty-eight OCD subjects and 96 healthy volunteers were tested on a reward and 30 OCD subjects and 53 healthy volunteers on the loss version of the two-step task. Thirty-six OCD subjects and 72 healthy volunteers were also tested on a one-step reversal task. OCD subjects compared with healthy volunteers were less goal oriented (model-based) and more habitual (model-free) to reward outcomes with a shift towards greater model-based and lower habitual choices to loss outcomes. OCD subjects also had enhanced acquisition learning to loss outcomes on the one-step task, which correlated with goal-directed learning in the two-step task. OCD subjects had greater stay behaviours or perseveration in the one-step task irrespective of outcome. Compulsion severity was correlated with habitual learning in the reward condition. Obsession severity was correlated with greater switching after loss outcomes. In healthy volunteers, we further show that greater reward magnitudes are associated with a shift towards greater goal-directed learning further emphasizing the role of outcome salience. Our results highlight an important influence of motivation on learning processes in OCD and suggest that distinct clinical strategies based on valence may be warranted.


Subject(s)
Goals , Habits , Motivation , Reward , Adult , Female , Humans , Male , Obsessive-Compulsive Disorder/psychology , Psychomotor Performance
5.
Br J Cancer ; 95(3): 314-21, 2006 Aug 07.
Article in English | MEDLINE | ID: mdl-16832409

ABSTRACT

We previously developed an immunohistochemical method for estimating cell cycle state and phase in tissue samples, including biopsies that are too small for flow cytometry. We have used our technique to examine whether primary abnormalities of the cell cycle exist in laryngeal neoplasia. Antibodies against the markers of cell cycle entry, minichromosome maintenance protein-2 (Mcm-2) and Ki67, and putative markers of cell cycle phase, cyclin D1 (G1-phase), cyclin A (S-phase), cyclin B1 (G2-phase) and phosphohistone H3 (Mitosis) were applied to paraffin-embedded sections of normal larynx (n = 8), laryngeal dysplasia (n = 10) and laryngeal squamous cell carcinoma (n = 10). Cells expressing each marker were determined as a percentage of total cells, termed the labelling index (LI), and as a percentage of Mcm-2-positive cells, termed the labelling fraction (LF). The frequency of coexpression of each putative phase marker was investigated by confocal microscopy. There was a correlation between Mcm-2 and Ki67 LIs (rho = 0.93) but Mcm-2 LIs were consistently higher. All cells expressing a phase marker coexpressed Mcm-2, whereas Ki67 was not expressed in a proportion of these cells. The putative phase markers showed little coexpression. Labelling index values increased on progression from normal larynx through laryngeal dysplasia to squamous cell carcinoma for Mcm-2 (P = 0.001), Ki67 (P = 0.0002), cyclin D1 (P = 0.015), cyclin A (P = 0.0001) and cyclin B1 (P = 0.0004). There was no evidence of an increase in the LF for any phase marker. Immunohistochemistry can be used to estimate cell cycle state and phase in laryngeal biopsies. Our data argues against primary cell cycle phase abnormalities in laryngeal neoplasia.


Subject(s)
Carcinoma, Squamous Cell/pathology , Laryngeal Neoplasms/pathology , Biomarkers, Tumor/biosynthesis , Cell Cycle , Cell Cycle Proteins/biosynthesis , G1 Phase , G2 Phase , Humans , Immunohistochemistry , Ki-67 Antigen/biosynthesis , Microscopy, Confocal/methods , Minichromosome Maintenance Complex Component 2 , Mitosis , Nuclear Proteins/biosynthesis , Paraffin Embedding , S Phase , Sensitivity and Specificity
6.
Br J Cancer ; 94(8): 1170-5, 2006 Apr 24.
Article in English | MEDLINE | ID: mdl-16622441

ABSTRACT

Squamous dysplasia of the oral cavity indicates increased risk of progression to squamous cell carcinoma (SCC). An important advance would be the development of a minimally invasive assay for identification of oral SCC and dysplasia. We have investigated the suitability in this context of immunostaining oral smears for minichromosome maintainance proteins (MCMs), sensitive and specific biomarkers of cell cycle entry. Immunohistochemical examination of 66 oral tissue samples showed a greater frequency of Mcm-2 expression in surface layers of moderate/severe dysplasia and SCC compared to benign keratosis/mild dysplasia. Immunocytochemistry for Mcm-2/Mcm-5 was performed on 101 oral smears. Conventional smears included 23 from normal mucosa, benign proliferative disease and mild dysplasia, all of which were MCM negative. Of 52 conventional smears of SCC tissue samples, 18 were inadequate. However, MCM-positive cells were present in 33/34 adequate samples. Of 26 liquid-based cytology smears, 19 out of 20 smears from SCC were adequate and all were MCM positive. Six smears from benign lesions were adequate and MCM negative. We conclude that MCMs are promising markers for early detection of oral SCC and dysplasia, particularly in a liquid-based cytology platform. Detection of MCMs would be amenable to automation and potentially applicable in the developing world. Further studies are now warranted.


Subject(s)
Biomarkers, Tumor/analysis , Carcinoma, Squamous Cell/diagnosis , Cell Cycle Proteins/analysis , Mouth Neoplasms/diagnosis , Nuclear Proteins/analysis , Precancerous Conditions/diagnosis , Biomarkers, Tumor/biosynthesis , Carcinoma, Squamous Cell/pathology , Cell Cycle Proteins/biosynthesis , Humans , Immunohistochemistry , Minichromosome Maintenance Complex Component 2 , Mouth Mucosa/chemistry , Mouth Mucosa/pathology , Mouth Neoplasms/pathology , Nuclear Proteins/biosynthesis , Paraffin Embedding , Precancerous Conditions/pathology , Sensitivity and Specificity , Staining and Labeling , Tissue and Organ Harvesting/methods
7.
Br J Cancer ; 90(8): 1583-90, 2004 Apr 19.
Article in English | MEDLINE | ID: mdl-15083189

ABSTRACT

We have investigated whether immunohistochemical markers can identify differences in cell cycle phase distribution in ovarian serous neoplasms, including borderline tumours of different grades. Sections of normal ovary (n=18), serous cystadenoma (n=21), borderline serous tumours (n=21) and serous cystadenocarcinoma (n=15) were analysed by immunohistochemistry using markers of cell cycle entry (Mcm-2) and cell cycle phase, including cyclin D1 (mid-to-late G1), cyclin A (S phase), cyclin B1 (G2 phase) and phosphohistone H3 (mitosis). Double-labelling confocal microscopy confirmed marker phase specificity and phase estimations were corroborated by flow cytometry. On progression from normal ovary through serous cystadenoma and borderline tumours to cystadenocarcinomas, expression of Mcm-2 (P<0.0001), cyclin D1 (P=0.002), cyclin A (P<0.0001), cyclin B1 (P<0.0001) and phosphohistone H3 (P<0.0001) increased, paralleled by an increase in the S-phase fraction (cyclin A : Mcm-2 ratio; P=0.002). Borderline tumours of increasing grade also showed increased Mcm-2 and cyclin A expression, together with an increase in the S-phase fraction. Immunohistochemistry can be used to estimate cell cycle phase distribution in ovarian serous neoplasms, giving results similar to flow cytometric analysis and enabling direct assessment of tumour heterogeneity. Immunohistochemical estimates of the S-phase fraction may identify serous borderline tumours likely to exhibit malignant progression and/or select serous cystadenocarcinomas likely to respond to adjuvant therapy.


Subject(s)
Biomarkers, Tumor/analysis , Cell Cycle Proteins/analysis , Cell Cycle , Cystadenocarcinoma, Serous/pathology , Ovarian Neoplasms/pathology , Cell Cycle Proteins/biosynthesis , Cell Transformation, Neoplastic , Disease Progression , Female , Flow Cytometry , Humans , Immunohistochemistry/methods , Microscopy, Confocal , Precancerous Conditions , Specimen Handling
8.
Colorectal Dis ; 6(2): 103-10, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15008907

ABSTRACT

OBJECTIVE: Minichromosome maintenance protein 2 (Mcm2) is an accurate indicator of cell cycle entry in tissue samples, but its expression in inflammatory bowel disease (IBD) has not previously been investigated. We have used immunohistochemistry to assess the expression of Mcm2, in comparison to the existing proliferation marker Ki-67, in active IBD and IBD without inflammatory activity. MATERIALS AND METHODS: For this experimental study, sections from colonic biopsy and resection specimens of 48 patients with IBD (5 inactive/quiescent Crohn's disease (CD), 13 active CD, 19 inactive/quiescent ulcerative colitis (UC) and 11 active UC) and 15 normal controls were immunostained with antibodies to Mcm2 and Ki-67. The percentage of immunopositive epithelial nuclei was determined by calculating a labelling index (LI) for entire glands and for gland thirds (superficial, middle and basal). RESULTS: The Mcm2 LI was significantly increased in the superficial third of glands in active vs. inactive/quiescent UC (P < 0.0001) and active vs. inactive/quiescent CD (P = 0.001). The Mcm2 LI was significantly greater than the Ki-67 LI in active IBD, both in entire glands (P < 0.0001) and in the superficial third of glands (UC, P = 0.001; CD, P = 0.0002). Mcm2 LIs for entire glands were significantly higher in UC (all cases) compared to CD (all cases) (P = 0.032). CONCLUSIONS: There is increased cell cycle entry, as indicated by expression of Mcm2 and to a lesser extent Ki-67, in the superficial third of colonic glands in active IBD compared to inactive/quiescent IBD. Detection of Mcm2 may contribute to improved histological assessment of small tissue biopsies and may enable the development of a direct stool-based test for detection of active IBD and potentially for assessment of disease activity.


Subject(s)
Cell Cycle Proteins/biosynthesis , Colon/metabolism , Inflammatory Bowel Diseases/metabolism , Intestinal Mucosa/metabolism , Colitis, Ulcerative/metabolism , Crohn Disease/metabolism , Humans , Ki-67 Antigen/biosynthesis
9.
Br J Cancer ; 89(6): 1048-54, 2003 Sep 15.
Article in English | MEDLINE | ID: mdl-12966424

ABSTRACT

Histological classification of laryngeal epithelial lesions is highly subjective, and methods of cytological detection are not well developed. Improved determination of aberrant cell cycle entry may allow increased objectivity in histological assessment and enable the development of less invasive diagnostic cytology tests. Sections of normal larynx (n=10), laryngeal dysplasia (n=20) and laryngeal squamous cell carcinoma (SCC) (n=10) were classified according to the Ljubljana classification and stained for markers of cell cycle entry, minichromosome maintenance protein-2 (Mcm-2) and Ki67. Expression patterns were compared using double labelling confocal microscopy. There was a correlation between Mcm-2 and Ki67 labelling indices (rho=0.93; 95% CI [0.84, 0.97]) and both markers showed increased expression from normal epithelium to SCC (Mcm-2, P=0.001; Ki67, P=0.0002). Importantly, there was minimal expression of Mcm-2 or Ki67 in the most superficial layers of normal larynx and abnormal or atypical hyperplasia, in contrast to carcinoma in situ and SCC. Clusters of Mcm-2/5-positive cells were present in cytological preparations from SCC, but not from those showing atypical hyperplasia or inflammation in non-neoplastic tissue. Minichromosome maintenance protein-2 staining may increase the objectivity and reliability of histological grading of laryngeal epithelial lesions. Laryngeal brushings, combined with immuno-enhanced liquid-based cytology, could be useful, as a less invasive approach, to the detection of laryngeal malignant and premalignant lesions.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Squamous Cell/metabolism , Ki-67 Antigen/metabolism , Laryngeal Neoplasms/metabolism , Nuclear Proteins/metabolism , Antigens, Neoplasm/metabolism , Biopsy , Carcinoma in Situ/metabolism , Carcinoma in Situ/pathology , Carcinoma, Squamous Cell/pathology , Cell Cycle , DNA Replication , Humans , Hyperplasia/metabolism , Hyperplasia/pathology , Immunoenzyme Techniques , Laryngeal Neoplasms/pathology , Minichromosome Maintenance Complex Component 2 , Precancerous Conditions/metabolism , Precancerous Conditions/pathology
10.
Virchows Arch ; 443(1): 51-6, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12759751

ABSTRACT

We have used immunohistochemistry to test the hypothesis that components of the desmosome are disrupted during neoplastic progression of squamous epithelial cells in the uterine cervix. Sections of normal cervix and squamous intraepithelial lesions (SILs) were immunostained for desmosomal proteins and glycoproteins, and results were assessed using a semi-quantitative grading system. No difference between normal cervix and low-grade SIL (LSIL) was found. A significant reduction in expression of desmogleins was seen between high-grade SIL (HSIL) and LSIL (P<0.01) and normal cervix (P<0.001). Desmocollin expression was not reduced significantly, although scores showed significantly greater variation in HSIL compared with LSIL (P<0.05) and normal cervix (P<0.05). There was no significant difference in desmoplakin expression among the three groups. The results suggest that there may be sequential disruption of desmosomal function during neoplastic progression of cervical squamous intraepithelial cells, with downregulation of desmogleins during the progression from LSIL to HSIL and loss of desmocollin expression occurring in some cases of established HSIL.


Subject(s)
Cytoskeletal Proteins/metabolism , Desmosomes/metabolism , Uterine Cervical Dysplasia/metabolism , Uterine Cervical Neoplasms/metabolism , Biomarkers, Tumor/metabolism , Cytoskeletal Proteins/classification , Desmocollins , Desmogleins , Desmoplakins , Female , Humans , Immunoenzyme Techniques , Uterine Cervical Neoplasms/pathology , Uterine Cervical Dysplasia/pathology
11.
Histopathology ; 42(5): 498-502, 2003 May.
Article in English | MEDLINE | ID: mdl-12713628

ABSTRACT

AIMS: The differentiation of benign pleural conditions from malignant mesothelioma may be difficult, especially with a small biopsy. We have tested the hypothesis that assessment of the cell cycle status is of value in the histopathological diagnosis of such biopsies, by comparing 33 malignant mesotheliomas with 36 cases of reactive mesothelial hyperplasia and reactive pleural fibrosis. METHODS AND RESULTS: Biopsies were investigated for proliferative status by immunostaining for a novel antibody, MCM2, all of which showed nuclear expression of MCM2 at higher frequency than Ki67 (P < 0.0001). Counts in areas of maximum tumour staining showed significantly higher labelling indices (LIMax) in epithelioid and sarcomatoid mesotheliomas compared with reactive mesothelial hyperplasia and reactive pleural fibrosis (P < 0.0001 for both). Average counts (LIAve) revealed a significant increase in epithelioid mesothelioma compared with reactive mesothelial hyperplasia (P < 0.0001). CONCLUSION: We consider MCM2 to be a useful adjunct in the differential diagnosis of malignant mesothelioma.


Subject(s)
Cell Cycle , Epithelium/pathology , Mesothelioma/pathology , Pleura/pathology , Pleural Neoplasms/pathology , Biomarkers, Tumor/metabolism , Biopsy , Cell Count , Diagnosis, Differential , Fibrosis/pathology , Humans , Hyperplasia/pathology , Immunoenzyme Techniques , Ki-67 Antigen/metabolism , Mesothelioma/metabolism , Minichromosome Maintenance Complex Component 2 , Nuclear Proteins/metabolism
12.
Br J Cancer ; 88(2): 257-62, 2003 Jan 27.
Article in English | MEDLINE | ID: mdl-12610511

ABSTRACT

Vulval intraepithelial neoplasia (VIN) is defined histopathologically by distinctive abnormalities of cellular maturation and differentiation. To investigate the functional properties of VIN, the expression of several proteins involved in the regulation of the cell cycle as well as in situ DNA replication competence was analysed by immunohistochemistry. Snap-frozen vulval biopsies were graded as normal squamous epithelium (n=6), undifferentiated HPV positive VIN 1 (n=3), VIN 2 (n=8) and VIN 3 (n=20). Immunohistochemistry was performed using the following markers: cyclin D1 (expressed in middle/late G1), cyclin B1 (expressed in G2/early M), phosphorylated histone H3 (expressed during mitosis) and minichromosome maintenance (Mcm) proteins 2 and 5 (expressed during the cell cycle, but not in differentiated or quiescent cells). In situ DNA replication competence was used to identify S-phase cells. The percentage of positively stained nuclei in three representative microscopic fields was calculated per biopsy. In normal vulva, the expression of all markers was restricted to the proliferative compartment of the basal layer of the epithelium. In contrast in high-grade VIN, the majority of epithelial cells expressed the Mcm proteins from basal to superficial layer. The detection of cyclins B1 and D1, phospho-histone H3 and in situ DNA replication was also found through the full thickness of these lesions but by a lower proportion of the cells. This is consistent with these markers providing a series of 'snapshots' of the cell cycle status of individual cells. The low-grade VIN showed reduced expression of the cell cycle markers in relation to the level of dysplasia. The combination of these analyses establishes that the majority of VIN cells remain in a functional replicative or prereplicative state of the cell cycle. Clinical application of these analyses may provide a basis for improved diagnosis of VIN.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma in Situ/genetics , Carcinoma in Situ/metabolism , DNA Replication , DNA, Neoplasm/metabolism , Vulvar Neoplasms/genetics , Vulvar Neoplasms/metabolism , Biopsy , Carcinoma in Situ/pathology , Cell Cycle , Cell Cycle Proteins/metabolism , Cyclin B/metabolism , Cyclin B1 , Cyclin D1/genetics , Cyclin D1/metabolism , DNA-Binding Proteins , Female , Histones/genetics , Humans , Immunoenzyme Techniques , Minichromosome Maintenance Complex Component 2 , Nuclear Proteins/metabolism , Schizosaccharomyces pombe Proteins , Vulvar Neoplasms/pathology
13.
J Pathol ; 198(4): 511-6, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12434421

ABSTRACT

The association of autoimmune phenomena with atherosclerosis suggests that plaques may contain specialized antigen-presenting cells, dendritic cells (DCs). DC-SIGN is a C-type lectin expressed by DCs. This study assessed whether human atherosclerotic plaques expressed DC-SIGN and several other macrophage/DC markers. Plaques from human coronary and carotid arteries and aorta contained DC-SIGN-immunoreactive cells. Double-labelling showed co-expression of DC-SIGN and macrophage/DC lineage markers CD14, CD68, HLA-DR, and S100. There was no immunoreactivity for the DC activation markers CD83 or CMRF-44. Since DC-SIGN mediates adhesion to T-lymphocytes and endocytosis, its expression in atherosclerotic plaques may have functional implications. Activated DCs migrate quickly from areas of inflammation to regional lymph nodes, possibly explaining the paucity of activated DCs in atherosclerotic plaques. In conclusion, this study has shown that DC-SIGN is expressed in atherosclerosis.


Subject(s)
Arteriosclerosis/metabolism , Cell Adhesion Molecules/metabolism , Dendritic Cells/metabolism , Lectins, C-Type/metabolism , Macrophages/metabolism , Receptors, Cell Surface/metabolism , Aorta, Abdominal/metabolism , Aortic Diseases/metabolism , Aortic Diseases/pathology , Arteriosclerosis/pathology , Biomarkers/analysis , Carotid Artery Diseases/metabolism , Coronary Artery Disease/metabolism , Coronary Artery Disease/pathology , Humans , Immunoenzyme Techniques
14.
Br J Neurosurg ; 16(1): 10-5, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11928726

ABSTRACT

We have investigated the potential utility of monoclonal antibodies against mini-chromosome maintenance-2 protein (Mcm2) in predicting meningioma recurrence. MCM proteins are members of the DNA-binding prereplicative complex and are essential for eukaryotic DNA replication. They are present throughout the cell cycle, but are down-regulated in quiescence and cell differentiation, making them specific markers of proliferating cells. We analysed 10 benign meningiomas that subsequently recurred within a 5-year period, together with 20 matched non-recurrent benign meningiomas. There was no significant correlation between histological subtype, mitotic count or Ki-67 labelling index and tumour recurrence. We observed that whilst the average Mcm2 labelling index (LI) of the tumour section as a whole (LI(Ave)) is not significantly different between recurrent and nonrecurrent meningiomas, the Mcm2 labelling index in the area of highest proliferative activity within the tumour section (LI(Max)) is significantly higher in recurrent meningiomas (p < 0.0001). Seven out of the 10 recurrent meningiomas displayed a Mcm2 LI((Max) greater than 30%, compared to 0 out of 20 for non-recurrent tumours. In conclusion, these results suggest that analysis of Mcm2 expression may facilitate identification of patients with a high risk of meningioma recurrence, for whom adjuvant radiotherapy may be of benefit.


Subject(s)
Biomarkers, Tumor/analysis , Meningioma/chemistry , Neoplasm Proteins/analysis , Neoplasm Recurrence, Local/chemistry , Nuclear Proteins/analysis , Adult , Aged , Antibodies, Monoclonal/immunology , DNA Replication , Female , Follow-Up Studies , Humans , Immunoenzyme Techniques , Male , Meningioma/pathology , Middle Aged , Minichromosome Maintenance Complex Component 2 , Mitotic Index , Neoplasm Recurrence, Local/pathology , Nuclear Proteins/immunology , Prognosis
15.
J Pathol ; 195(5): 586-92, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11745695

ABSTRACT

Mechanisms of transplacental transmission of human immunodeficiency virus (HIV) are poorly understood. DC-SIGN is a C-type lectin able to bind HIV gp120 with high affinity, mediating HIV adsorption to the surface of dendritic cells for up to several days. Via this mechanism, DC-SIGN significantly enhances the infection of CD4(+) co-receptor (CCR5 or CXCR4)(+) T lymphocytes in trans. In this study, DC-SIGN-specific serum was developed to investigate the cell type responsible for the high level of DC-SIGN RNA expression previously observed in the placenta. DC-SIGN expression was shown on CD68(+) HLA-II(+) CD14(low) S100(+/-) CD83(-) CD86(-) cmrf-44(-) villous cells consistent with Hofbauer cells and also on CD68(+) HLA-II(+) CD14(high) S100(-) CD83(-) CD86(-) cmrf-44(-) decidual macrophages. The DC-SIGN(+) Hofbauer cells co-express CD4 and the chemokine receptors, CCR5 and CXCR4, observations which may account for the ability of these cells to become infected with HIV. These fetal DC-SIGN(+) cells are separated by only a layer of trophoblast from both DC-SIGN(+) maternal cells and maternal blood, potential sources of HIV in infected mothers. Previous studies have suggested that this trophoblast layer is frequently breached during pregnancy. It is therefore proposed that DC-SIGN may facilitate the transplacental transmission of HIV.


Subject(s)
Cell Adhesion Molecules , HIV Infections/transmission , Infectious Disease Transmission, Vertical , Lectins, C-Type , Lectins/metabolism , Placenta/metabolism , Pregnancy Complications, Infectious/metabolism , Receptors, Cell Surface/metabolism , Antibody Specificity , Female , HIV Infections/metabolism , Humans , Immune Sera/immunology , Lectins/immunology , Macrophages/metabolism , Pregnancy , Receptors, CCR5/metabolism , Receptors, CXCR4/metabolism , Receptors, Cell Surface/immunology , Receptors, HIV/metabolism
16.
Int J Gynecol Cancer ; 11(3): 187-93, 2001.
Article in English | MEDLINE | ID: mdl-11437923

ABSTRACT

Ionizing radiation has been used to treat cancers for a century. However, radioresistance remains a major problem in the clinic. Recent advances in the understanding of the molecular events that occur following ionizing radiation leading to DNA damage and repair, apoptosis, and cell cycle arrests suggest new ways in which the radiation response might be manipulated. Seventy-eight cases of carcinoma of the cervix of the same stage (II A and B) were analyzed retrospectively. All patients were treated with radiotherapy (RT) with a dose varying from 35 Gy to 50 Gy with 200 cGy per fraction. Subsequent to the completion of radiotherapy, all patients underwent surgery 4-6 weeks later. On histological examination of the surgical specimens, 51% of the cases (40) showed a complete response to therapy with no viable tumor cells. 49% of cases (38) had residual tumors ranging from a small focus to lesions extending through more than half the thickness of the cervical wall. p53 (mutant), bcl-2, p21 and bax proteins were studied on the paraffin sections of the biopsies (pretreatment) of those patients who failed to respond to RT and compared to similar studies on biopsies of patients who had a complete response to RT. In addition, the minichromosome maintenance (MCM) 2 proliferative marker was also done on all cases. Expression of all proteins was done using immunohistochemsitry. In the radioresistant cases, 15% (six cases) showed positivity for bcl-2 and p21, respectively, and 34% (13 cases) showed mutant p53. None of the radiosensitive tumors were positive for the above proteins. 75% of the radiosensitive tumors (30 cases) were positive for the bax antibody, whereas 81% of the radioresistant tumors (31 cases) were negative for bax. The MCM2 proliferative marker was positive in > 80% of cells in 81.5% of radioresistant tumors (31 cases) as compared to < 40% of cells that were positive in 70% of radiosensitive tumors (28 cases). The P-value for the biological markers was calculated using the chi-squared test, and was highly significant (P < 0.01) for all the parameters tested. However, there was no statistical significance by univariate analysis when the dose of radiation was analyzed with respect to the markers and the histological response. There was also no correlation between the radiation response and timing of surgery. The above data strongly suggest that bax, along with proliferative markers, could play a role in determining which tumors are likely to respond to radiation therapy. The presence of bcl-2, p21 and p53 could also be related to radioresistance of the tumors.


Subject(s)
Biomarkers, Tumor/metabolism , Biomarkers, Tumor/radiation effects , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/radiotherapy , Proto-Oncogene Proteins c-bcl-2 , Uterine Cervical Neoplasms/metabolism , Uterine Cervical Neoplasms/radiotherapy , Apoptosis Regulatory Proteins , Carrier Proteins/metabolism , Carrier Proteins/radiation effects , Female , Humans , Immunohistochemistry , Medical Records , Minichromosome Maintenance Complex Component 2 , Nuclear Proteins/metabolism , Nuclear Proteins/radiation effects , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins/radiation effects , Retrospective Studies , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Protein p53/radiation effects , bcl-2-Associated X Protein , rho GTP-Binding Proteins/metabolism , rho GTP-Binding Proteins/radiation effects
17.
Proc Natl Acad Sci U S A ; 98(5): 2670-5, 2001 Feb 27.
Article in English | MEDLINE | ID: mdl-11226297

ABSTRACT

DC-SIGN, a C-type lectin expressed on the surface of dendritic cells (DCs), efficiently binds and transmits HIVs and simian immunodeficiency viruses to susceptible cells in trans. A DC-SIGN homologue, termed DC-SIGNR, has recently been described. Herein we show that DC-SIGNR, like DC-SIGN, can bind to multiple strains of HIV-1, HIV-2, and simian immunodeficiency virus and transmit these viruses to both T cell lines and human peripheral blood mononuclear cells. Binding of virus to DC-SIGNR was dependent on carbohydrate recognition. Immunostaining with a DC-SIGNR-specific antiserum showed that DC-SIGNR was expressed on sinusoidal endothelial cells in the liver and on endothelial cells in lymph node sinuses and placental villi. The presence of this efficient virus attachment factor on multiple endothelial cell types indicates that DC-SIGNR could play a role in the vertical transmission of primate lentiviruses, in the enabling of HIV to traverse the capillary endothelium in some organs, and in the presentation of virus to CD4-positive cells in multiple locations including lymph nodes.


Subject(s)
Cell Adhesion Molecules , Endothelium/metabolism , HIV-1/metabolism , HIV-2/metabolism , Lectins, C-Type , Lectins/metabolism , Receptors, Cell Surface/metabolism , Simian Immunodeficiency Virus/metabolism , Amino Acid Sequence , Binding Sites , Cell Line , Endothelium/cytology , Humans , Lectins/genetics , Liver/cytology , Liver/metabolism , Liver/virology , Lymph Nodes/cytology , Lymph Nodes/metabolism , Lymph Nodes/virology , Molecular Sequence Data , Monocytes/virology , Placenta/cytology , Placenta/metabolism , Placenta/virology , Protein Binding , Receptors, Cell Surface/genetics , T-Lymphocytes/virology
19.
Acta Paediatr ; 88(8): 841-3, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10503682

ABSTRACT

The aim of this study was to assess whether nebulized budesonide may substitute for oral prednisolone in the management of children whose asthma is severe enough to warrant hospital admission, but who have no life threatening features. In a prospective, double-blind, randomized study nebulized budesonide (2 mg 8 hourly) was compared with oral prednisolone (2 mg/kg at entry and again at 24 h) in 46 children admitted to hospital with severe asthma exacerbations. Efficacy variables (including lung function measurements such as the primary outcome variable, Forced Expiratory Volume in 1 second (FEV1) and symptoms) were measured 24 h after treatment initiation. FEV1 improved significantly compared to baseline in patients who received nebulized budesonide compared to the prednislone group. The data show nebulized budesonide to be at least as effective as oral steroid in improving lung function and symptom severity in severe exacerbations of childhood asthma.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Asthma/drug therapy , Bronchodilator Agents/therapeutic use , Budesonide/therapeutic use , Prednisolone/therapeutic use , Administration, Inhalation , Administration, Oral , Anti-Inflammatory Agents/administration & dosage , Bronchodilator Agents/administration & dosage , Budesonide/administration & dosage , Child , Double-Blind Method , Female , Forced Expiratory Volume/drug effects , Humans , Male , Nebulizers and Vaporizers , Prednisolone/administration & dosage
20.
Clin Cancer Res ; 5(8): 2121-32, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10473096

ABSTRACT

Dysplasia, an intermediate stage in the progression from normal tissue to neoplasia, is defined morphologically by a loss of normal orientation between epithelial cells, with changes in cellular and nuclear shape and size. However, little is known about the functional properties of dysplastic cells, including their replicative state, largely due to a lack of available biological markers. We have used novel antibodies against minichromosome maintenance (MCM) proteins to examine the proliferative status of a range of histological lesions and to characterize dysplastic cells in functional terms. Immunoperoxidase staining was used to localize the MCM proteins, components of the prereplicative complex that is essential for initiating eukaryotic DNA replication. These proteins are down-regulated in cells undergoing differentiation or quiescence and, thus, serve as specific markers for proliferating cells. In normal and some reactive tissues, MCM expression was present only in restricted proliferative compartments, consistent with our published findings in the uterine cervix. In dysplastic and malignant tissues, in contrast, MCM proteins were expressed in the majority of cells, extending to surface layers of dysplastic stratified epithelia. In carcinomas, the frequency of expression of MCM proteins showed an inverse correlation with the degree of tumor differentiation. Thus, we suggest that dysplastic cells may be characterized in functional terms as remaining in cell cycle, due to deregulation of normal controls over cell proliferation. Antibodies against MCM proteins have potential clinical applications, for example, in the assessment of tumor prognosis in histological sections and the identification of proliferating cells in clinical samples using biochemical or cytological assays.


Subject(s)
Biomarkers, Tumor/metabolism , Cell Cycle Proteins/metabolism , DNA-Binding Proteins/metabolism , Fungal Proteins/metabolism , Neoplasms/metabolism , Nuclear Proteins/metabolism , Precancerous Conditions/metabolism , Cell Division , Chromosomes/metabolism , Female , Fluorescent Antibody Technique , Humans , Immunoblotting , Immunohistochemistry , Male , Minichromosome Maintenance Complex Component 2 , Minichromosome Maintenance Complex Component 7 , Organ Specificity , Schizosaccharomyces pombe Proteins
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