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J J O'Leary

Publications and source records attributed to J J O'Leary.

At least 19 recordsLinked to original sources
PubMed2003

Analysis of fetal DNA in the maternal venous blood for abnormalities of chromosomes 13, 16, 18 and 21 in first-trimester spontaneous miscarriage.

We investigated whether fetal DNA from the maternal blood can be used to diagnose abnormalities of chromosomes 13, 16, 18 and 21 in spontaneous miscarriage. Venous blood was obtained from 50 women with a diagnosis of spontaneous miscarriage. The evacuated products of the uterus were also sampled. DNA was extracted from both blood and tissue samples. Polymerase chain reaction (PCR) was performed using microsatellite markers for selected chromosomes. A novel technique using a capillary sequencer was employed. The electrophoretogram created was analysed using GeneScan software. The result obtained from the maternal blood samples was compared to the result obtained from uterine samples. Forty-two of the 50 (84%) cases were found to have a trisomy of one or more of the chromosomes tested on analysis of maternal blood. Compared to the overall result obtained on the uterine products of conception, the sensitivity was 97.6 and specificity 1.0. Trisomy 16 was the most common abnormality detected. These results suggest that the incidence of genetic abnormalities complicating miscarriage may be higher than suspected hitherto.

Abortion, Spontaneous↗
PubMed2003

p16INK4A as a marker for cervical dyskaryosis: CIN and cGIN in cervical biopsies and ThinPrep smears.

AIM: To examine the potential of p16(INK4A) as a biomarker for dysplastic squamous and glandular cells of the cervix in tissue sections and ThinPrep smears. METHODS: Immunocytochemical analysis of p16(INK4A) expression was performed on 22 normal cervical tissue samples, five cervical glandular intraepithelial neoplasia (cGIN), 38 cervical intraepithelial neoplasia 1 (CIN1), 33 CIN2, 46 CIN3, and 10 invasive cancer cases (eight squamous and two adenocarcinomas). All samples were formalin fixed and paraffin wax embedded, and immunohistochemical analysis was carried out using a mouse monoclonal anti-p16(INK4A) antibody after antigen unmasking. The staining intensity was assessed using a 0 to 3 scoring system. In addition, the expression status of p16(INK4A) was examined in 12 normal ThinPrep smears, one smear exhibiting cGIN, and a total of 20 smears exhibiting mild, moderate, and severe dyskaryosis. Human papillomavirus (HPV) detection was carried out using a modified SYBR green assay system. Fluorogenic polymerase chain reaction (PCR) and solution phase PCR were used for specific HPV typing. RESULTS: p16(INK4A) immunoreactivity was absent in all normal cervical tissues examined. Dysplastic squamous and glandular cells were positive for p16(INK4A) expression in all cases included in this study, except for one CIN3 case. p16(INK4A) expression was mainly nuclear in CIN1 cases, and both nuclear and cytoplasmic in CIN2, CIN3, cGIN, and invasive cases. All cases positive for HPV expressed the p16(INK4A) protein, although not all cases found positive for p16(INK4A) were HPV positive. In general, the p16(INK4A) staining intensity was lower in cases negative for HPV or those containing a low risk HPV type. CONCLUSION: This pattern of overexpression demonstrates the potential use of p16(INK4A) as a diagnostic marker for cervical squamous and also glandular neoplastic lesions. In addition, the technique can be used to identify individual dyskaryotic cells in ThinPrep smears. Thus, p16(INK4A) is a useful marker of cervical dyskaryosis.

Biomarkers↗
PubMed2002

Review article: the concept of entero-colonic encephalopathy, autism and opioid receptor ligands.

There is growing awareness that primary gastrointestinal pathology may play an important role in the inception and clinical expression of some childhood developmental disorders, including autism. In addition to frequent gastrointestinal symptoms, children with autism often manifest complex biochemical and immunological abnormalities. The gut-brain axis is central to certain encephalopathies of extra-cranial origin, hepatic encephalopathy being the best characterized. Commonalities in the clinical characteristics of hepatic encephalopathy and a form of autism associated with developmental regression in an apparently previously normal child, accompanied by immune-mediated gastrointestinal pathology, have led to the proposal that there may be analogous mechanisms of toxic encephalopathy in patients with liver failure and some children with autism. Aberrations in opioid biochemistry are common to these two conditions, and there is evidence that opioid peptides may mediate certain aspects of the respective syndromes. The generation of plausible and testable hypotheses in this area may help to identify new treatment options in encephalopathies of extra-cranial origin. Therapeutic targets for this autistic phenotype may include: modification of diet and entero-colonic microbial milieu in order to reduce toxin substrates, improve nutritional status and modify mucosal immunity; anti-inflammatory/immunomodulatory therapy; and specific treatment of dysmotility, focusing, for example, on the pharmacology of local opioid activity in the gut.

Autistic Disorder↗
PubMed2002

Evaluation of liquid-based cytology in cervical screening of high-risk populations: a split study of colposcopy and genito-urinary medicine populations.

A split study evaluated the ThinPrep(R) PapTesttrade mark (TP; Cytyc Corp., Boxborough, MA) compared with current methodologies of cervical cytology in two high-risk cohorts. One thousand, three hundred cases from a colposcopy clinic and a genito-urinary medicine outpatient clinic were examined. The TP reported increased detection of all grades of dyskaryosis (mild, moderate and severe; + 4.5%) and a decrease in borderline and unsuitable cases (- 4.9%). Four cases of high-grade dyskaryosis (moderate or severe) were detected only using the TP, while an additional four cases classified as high-grade dyskaryosis with the TP were reported as borderline by our conventional methods. The split-study finding of increased sensitivity with the TP provides for improved clinical management of patients in our high-risk cohorts.

Cell Nucleus↗
PubMed2002

Potential viral pathogenic mechanism for new variant inflammatory bowel disease.

AIMS: A new form of inflammatory bowel disease (ileocolonic lymphonodular hyperplasia) has been described in a cohort of children with developmental disorder. This study investigates the presence of persistent measles virus in the intestinal tissue of these patients (new variant inflammatory bowel disease) and a series of controls by molecular analysis. METHODS: Formalin fixed, paraffin wax embedded and fresh frozen biopsies from the terminal ileum were examined from affected children and histological normal controls. The measles virus Fusion (F) and Haemagglutinin (H) genes were detected by TaqMan reverse transcription polymerase chain reaction (RT-PCR) and the Nucleocapsid (N) gene by RT in situ PCR. Localisation of the mRNA signal was performed using a specific follicular dendritic cell antibody. RESULTS: Seventy five of 91 patients with a histologically confirmed diagnosis of ileal lymphonodular hyperplasia and enterocolitis were positive for measles virus in their intestinal tissue compared with five of 70 control patients. Measles virus was identified within the follicular dendritic cells and some lymphocytes in foci of reactive follicular hyperplasia. The copy number of measles virus ranged from one to 300,00 copies/ng total RNA. CONCLUSIONS: The data confirm an association between the presence of measles virus and gut pathology in children with developmental disorder.

Adolescent↗
PubMed2001

Fetal DNA in maternal circulation of first-trimester spontaneous abortions.

OBJECTIVE: To establish whether fetal DNA can be identified in the maternal circulation in first-trimester spontaneous abortions. METHODS: Women with confirmed spontaneous abortions and no histories of previous pregnancy were recruited. Peripheral venous blood samples were obtained and DNA extracted. Real-time quantitative polymerase chain reaction was done using SRY and beta-actin systems for calculating fetal and total DNA, respectively. RESULTS: Of 25 women, SRY-specific signals were detected in 11 indicating that the abortions were male. The remaining 14 were negative for the SRY gene. Women with positive results were of similar gestational age to those who were negative (mean 68.4 and 69.0 days). Fetal:total DNA ratio was calculated for positive samples and ranged from 15.8 to 360.1 x 10(+3). Mean ratio was 99.4 x 10(+3) and median was 67.5 x 10(+3). CONCLUSION: Fetal DNA is present in the maternal circulation of first-trimester spontaneous abortions.

Abortion, Spontaneous↗
PubMed2001

Expression profile of human herpesvirus 8 (HHV-8) in pyothorax associated lymphoma and in effusion lymphoma.

AIMS: Pyothorax associated lymphoma (PAL) occurs in a clinical setting of longstanding pyothorax or chronic inflammation of the pleura. Like primary effusion lymphoma, it has an association with Epstein-Barr virus (EBV), and is confined to the pleural cavity, but has differing morphological and phenotypic features. Human herpesvirus 8 (HHV-8) has been consistently reported in primary effusion lymphoma. This study examines the immunophenotype of two European cases of PAL, investigates the presence of HHV-8 and its expression profile, and assesses whether PAL is similar to other effusion lymphomas. METHODS: Material was obtained from two European cases of PAL. Immunocytochemical analysis was performed using antibodies against CD45, CD20, CD79a, CD45RAA, CD3, CD43, CD45RO (UCHL1), CD30, BCL-2, CD68, epithelial membrane antigen (EMA), BCL-6, p53, Ki-67, kappa light chain, lambda light chain, and the EBV antigens latent membrane protein 1 (LMP-1) and EBV encoded nuclear antigen 2 (EBNA-2). The cases were examined for HHV-8 by means of polymerase chain reaction in situ hybridisation (PCR-ISH), solution phase PCR, in situ hybridisation (ISH), and real time quantitative TaqMan PCR to HHV-8 open reading frame 26 (ORF-26) and viral (v) cyclin encoding regions. The expression profile of HHV-8 in PAL and in BC-1 and BC-3 cells was assessed by RNA TaqMan PCR to the HHV-8 genes encoding v-cyclin, v-IL-6, and G protein coupled receptor (GPCR). RESULTS: Both cases expressed CD24, CD20, CD79a, BCL-2, light chain restriction, and high Ki-67 staining. EBV was identified by EBER-ISH in one case. HHV-8 was not identified by solution phase PCR, but was detected by PCR-ISH (sensitivity of 1 viral genome copy/cell) in 35% of the cells and by TaqMan PCR, which showed 50-100 HHV-8 copies/2,000 cell genome equivalents (sensitivity of 1 viral genome in 10(6) contaminating sequences). HHV-8 v-IL-6, v-cyclin, and GPCR encoded transcripts were identified using RNA TaqMan PCR. v-IL-6 was high in PAL and in BC-1 and BC-3 cells. CONCLUSION: The presence of HHV-8 in one of two patients with PAL raises interesting questions in relation to the pathobiology of the condition. Clearly, the results indicate that HHV-8 is not an obligate pathogen, necessary for the effusion phenotype, but might contribute to it by its secretion of specific cytokines.

Aged↗
PubMed2001

Drug approval summaries: arsenic trioxide, tamoxifen citrate, anastrazole, paclitaxel, bexarotene.

This report summarizes information on drugs recently approved by the Food and Drug Administration, Office of Drug Evaluation I, Division of Oncology Drug Products. Five applications supporting new claims will be discussed: Trisenox (arsenic trioxide) for induction of remission and consolidation in patients with acute promyelocytic leukemia who are refractory to, or have relapsed from, retinoid and anthracycline chemotherapy, and whose disease is characterized by the presence of the t(15;17) translocation or PML/RAR-alpha gene expression; Nolvadex (tamoxifen citrate) in women with ductal carcinoma in situ, following breast surgery and radiation, to reduce the risk of invasive breast cancer; Arimidex (anastrazole) for first-line treatment of postmenopausal women with hormone receptor positive or hormone receptor unknown locally advanced or metastatic breast cancer; Taxol (paclitaxel), 175 mg/m(2) by 3 h infusion in combination with cisplatin for first-line treatment of advanced ovarian cancer; and Targretin gel (bexarotene) for the topical treatment of cutaneous lesions in patients with stage IA and IB cutaneous T-cell lymphoma who have not tolerated other therapies or who have refractory or persistent disease. Information provided includes rationale for drug development, study design, efficacy and safety results, and pertinent literature references.

Anastrozole↗
PubMed2000

Assessment of ret/PTC-1 rearrangements in neoplastic thyroid tissue using TaqMan RT-PCR.

Among oncogenes studied in thyroid cancers, a specific activated form of c-ret has been found in a minority of papillary thyroid carcinomas (PTCs). In these tumours, c-ret is activated when by somatic rearrangements, the intracellular domain of RET is juxtaposed with the amino-terminal portion of a different donor gene such as H4, thereby generating a chimeric transcript (ret/PTC-1). The functional effects of c-ret activation and its prognostic implications are currently unclear. This study was undertaken to assess the frequency of RET/PTC-1 expression, any distinctive features of positive tumours to which it might be related, and its prognostic importance. Archival material from 88 thyroid neoplasms [50 PTCs, eight anaplastic carcinomas (ATCs), 25 follicular thyroid carcinomas (FTCs) and five follicular adenomas (FAs)] were analysed for ret/PTC-1 and H4 expression using 5' nuclease assay (TaqMan RT-PCR). RNA from the TPC-1 cell line was included as a positive control for c-ret activation. No FTC or FA displayed activation of ret/PTC-1, though all expressed H4. c-ret activation was found in 24% of PTCs (12 of 50), in 87.5% of ATCs (7 of 8), and in 33% of the combined PTC/ATC group. The frequency of c-ret activation in the aggressive ATC variants noted here suggests that ret/PTC-1-positive PTCs might also have a similar poor prognosis and a follow-up study on this cohort is in progress. Ninety per cent of ret/PTC-1-positive tumours failed to express H4, a phenomenon that has not been described previously and which may have considerable bearing on tumour morphology. A statistically significant proportion (58%) of ret/PTC-1-positive, H4-negative PTCs was associated with chronic inflammatory cell infiltration of the tumour and/or the surrounding thyroid. This association has not been reported previously.

Biomarkers, Tumor↗
PubMed2000

Enterocolitis in children with developmental disorders.

OBJECTIVE: Intestinal pathology, i.e., ileocolonic lymphoid nodular hyperplasia (LNH) and mucosal inflammation, has been described in children with developmental disorders. This study describes some of the endoscopic and pathological characteristics in a group of children with developmental disorders (affected children) that are associated with behavioral regression and bowel symptoms, and compares them with pediatric controls. METHODS: Ileocolonoscopy and biopsy were performed on 60 affected children (median age 6 yr, range 3-16; 53 male). Developmental diagnoses were autism (50 patients), Asperger's syndrome (five), disintegrative disorder (two), attention deficit hyperactivity disorder (ADHD) (one), schizophrenia (one), and dyslexia (one). Severity of ileal LNH was graded (0-3) in both affected children and 37 developmentally normal controls (median age 11 yr, range 2-13 yr) who were investigated for possible inflammatory bowel disease (IBD). Tissue sections were reviewed by three pathologists and scored on a standard proforma. Data were compared with ileocolonic biopsies from 22 histologically normal children (controls) and 20 children with ulcerative colitis (UC), scored in an identical manner. Gut pathogens were sought routinely. RESULTS: Ileal LNH was present in 54 of 58 (93%) affected children and in five of 35 (14.3%) controls (p < 0.001). Colonic LNH was present in 18 of 60 (30%) affected children and in two of 37 (5.4%) controls (p < 0.01). Histologically, reactive follicular hyperplasia was present in 46 of 52 (88.5%) ileal biopsies from affected children and in four of 14 (29%) with UC, but not in non-IBD controls (p < 0.01). Active ileitis was present in four of 51 (8%) affected children but not in controls. Chronic colitis was identified in 53 of 60 (88%) affected children compared with one of 22 (4.5%) controls and in 20 of 20 (100%) with UC. Scores of frequency and severity of inflammation were significantly greater in both affected children and those with UC, compared with controls (p < 0.001). CONCLUSIONS: A new variant of inflammatory bowel disease is present in this group of children with developmental disorders.

Adolescent↗
PubMed2000

Localisation of HHV-8 in AIDS related lymphadenopathy.

BACKGROUND: Many lymph node abnormalities have been described in AIDS. These include opportunistic infections that sometimes result in spindle cell pseudotumours, Kaposi's sarcoma (KS), malignant lymphoma (Hodgkin's and non-Hodgkin's), and florid reactive hyperplasia. Among these, reactive hyperplasia is the most common manifestation of AIDS related lymphadenopathy. AIM: To examine whether human herpesvirus 8 (HHV-8), the aetiological agent of KS, can be localised in AIDS related lymphadenopathy and whether its appearance in such nodes is predictive of Kaposi's sarcoma development. METHODS: A series of human immunodeficiency virus (HIV) positive men (n = 21) with AIDS related lymphadenopathy who at the time of presentation had KS or subsequently developed KS (n = 5) were examined. The prevalence of HHV-8 was assessed in these patients using solution phase polymerase chain reaction (PCR), real time TaqMan quantitative PCR, and in cell amplification techniques (PCR in situ hybridisation (PCR-ISH) and labelled primer driven in cell amplification). RESULTS: Using standard solution phase PCR in a nested format, only two of the 21 patients with AIDS related lymphadenopathy were positive for HHV-8. The lymph node of one of these patients contained KS lesions. Three HHV-8 positive patients were identified using TaqMan PCR (the original two positive patients and one additional patient). All of the positive patients either subsequently developed KS (n = 2) or had KS at the time of diagnosis (n = 1). Two additional patients subsequently developed KS, but were negative for HHV-8 by solution phase PCR and TaqMan PCR. Using PCR-ISH, HHV-8 amplicons were identified in some lymphoid cells (in one patient) and in spindle cells of the KS lesion in another. The positive lymphoid cells were predominantly concentrated in B cell areas of the affected lymph nodes, confirming the B cell tropism exhibited by HHV-8. CONCLUSIONS: The presence of HHV-8 in AIDS related lymphadenopathy is predictive of KS development and probably represents seeding of HHV-8 infected B cells from the peripheral blood. These findings support a role for HHV-8 in the pathobiology of KS.

AIDS-Related Complex↗
PubMed2000

Improved in situ detection method for telomeric tandem repeats in metaphase spreads and interphase nuclei.

Peptide nucleic acid technology (PNA) has become an extremely useful tool and promises to impact on molecular biology and diagnostics. These synthetic DNA analogues pair with DNA and RNA molecules according to Watson and Crick base pairing rules. This paper describes a sensitive and quick fluorescent in situ hybridisation (ISH) technique to determine DNA telomere repeat sequences (TTA GGG)n using epifluorescence microscopy. Telomeres are special, repeated structures at the end of each eukaryotic chromosome and serve as protective caps to prevent DNA rearrangements and fusion of chromosomes. A model system has been developed, using stimulated peripheral blood lymphocytes, which facilitates simultaneous detection of telomeres in metaphase as well as in interphase nuclei. A fluorescein isothiocyanate labelled PNA probe (18 mer) directed against complementary telomeric sequences at the end of each chromosome is used. In addition, a simple, easy to perform PNA-ISH protocol is described that overcomes common hybridisation problems encountered using DNA and RNA oligoprobes. Furthermore, the usefulness of a chromogenic immunocytochemical detection system is shown for PNA-ISH.

Humans↗
PubMed1999

Double immunolabeling with cytokeratin and smooth-muscle actin in confirming early invasive carcinoma of breast.

Histopathological identification of invasive breast carcinoma in its earliest phases is fraught with pitfalls. Preinvasive malignant lesions complicated by radial scar, sclerosing adenosis, and lobular cancerization, among other lesions, may simulate invasive carcinoma. Fibrosis, inflammatory reaction, and other stromal changes around in situ carcinoma may mask microinvasive foci on routine stains. Conventional immunohistochemistry to demonstrate basement membrane or myoepithelial cell layer may not, by itself, be unequivocally diagnostic of invasion. We performed a novel double immunoenzyme labeling technique using an avidin-biotin complex peroxidase-diaminobenzidine system for smooth-muscle actin followed by an alkaline phosphatase anti-alkaline phosphatase-new fuchsin system for cytokeratin antigen on formalin-fixed, paraffin-embedded histology sections to evaluate 32 such problematic cases. The initial histologic impression with hematoxylin and eosin staining alone was as follows-first group: microinvasive carcinoma-10; second group: carcinoma in situ--"stromal invasion cannot be ruled out"--15; third group: frankly infiltrating carcinoma of various grades and morphologic types-6. The last group served as positive control for invasion. One fibroadenoma with fine-needle-aspiration-induced artifact simulating stromal invasion was also included. The double immunoenzyme labeling technique imparted a dark brown color to the myoepithelial cells and a vivid red color to the epithelial cells, making individual or loosely cohesive groups of malignant epithelial cells infiltrating the stroma easily detectable, whereas their in situ counterparts were contained within dark brown myoepithelial boundaries. The TNM 1997 definition of pT1mic, i.e., extension of malignant cells in the stroma with no focus measuring >0.1 cm, was followed to classify microinvasion. In the first group, microinvasion was confirmed in six cases but was not demonstrable in four. In the second group, definite invasion was identified in five cases, ruled out in nine, and in one case the suspicion of early invasion could not be entirely ruled out even after double immunoenzyme labeling. Thus, it was possible to render a definite opinion regarding presence or absence of invasion in 24 of 25 (96%) cases diagnosed as or suspected to be microinvasive. The precise and simultaneous elucidation of topography between malignant cells and myoepithelial cells on a single permanent section makes this technique a useful diagnostic tool in the evaluation of those cases of breast carcinoma that exhibit equivocal invasion.

Actins↗
PubMed1999

Cyclin D1 expression and HHV8 in Kaposi sarcoma.

BACKGROUND: Human herpesvirus 8 (HHV8) appears to be the agent responsible for Kaposi sarcoma. The mechanism remains undetermined but may involve cell cycle regulating genes including D type cyclins which are pivotal in cell cycle progression. Recent HHV8 genetic analysis has revealed the presence of a v-cyclin which is homologous to D type cyclins. AIMS: First, to assess whether there is an independent relation between endogenous cyclin D1 expression in Kaposi sarcoma and HHV8 status; second to determine whether v-cyclin mRNA expression varies with Kaposi sarcoma stage. METHODS: Cyclin D1 immunohistochemistry was performed on 17 paraffin embedded Kaposi sarcoma samples from 16 patients. HHV8 status was assessed in 15 of these using nested polymerase chain reaction (PCR) to ORF 26 and the newly described technique of TaqMan PCR. An additional 10 fresh Kaposi sarcoma samples (early and nodular) were examined for HHV8 v-cyclin RNA. RESULTS: One case, which did not contain amplifiable HHV8, showed strong cyclin D1 staining. The remaining cases were negative or weakly staining; v-cyclin transcript load was higher in early Kaposi sarcoma. CONCLUSIONS: While endogenous cyclin D1 expression is independent of HHV8 status, v-cyclin transcription is higher in early lesions, supporting the "viral hit" hypothesis.

Cyclin D1↗
PubMed1999

CD40 upregulation is independent of HHV-8 in the pathogenesis of Kaposi's sarcoma.

AIMS: Human herpesvirus 8 (HHV-8) is now acknowledged as the infective cofactor in the pathogenesis of Kaposi's sarcoma. The mode by which HHV-8 causes Kaposi's sarcoma is unresolved and it is probable that it acts in conjunction with other factors including cytokines, anti-apoptosis proteins, and cell surface receptors. CD40, a cell membrane receptor belonging to the tumour necrosis factor receptor super family, promotes B cell survival and is expressed constitutively on endothelial cells. It is upregulated on cytokine treatment and has been documented recently in Kaposi's sarcoma. Because the HHV-8 genome contains cytokine homologues, this study investigated whether CD40 expression in Kaposi's sarcoma correlated with HHV-8 status, using a unique set of HHV-8 positive and negative specimens. METHODS: Twenty one paraffin wax embedded samples of Kaposi's sarcoma were selected, of which 18 were screened for the presence of HHV-8 using both conventional solution phase and TaqMan polymerase chain reaction (PCR). CD40 immunohistochemistry was assessed using a biotinylated amplification system. Staining was scored semiquantitatively. RESULTS: The results indicated that the expression of CD40 is independent of viral status, being present in both HHV-8 positive and negative specimens. CONCLUSIONS: This suggests that HHV-8 promotes Kaposi's sarcoma cell survival following infection by mechanisms other than those involving CD40.

Antigens, Neoplasm↗