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D M Barnes

Publications and source records attributed to D M Barnes.

At least 91 records · Page 5Linked to original sources
PubMed1995

Loss of heterozygosity of the oestrogen receptor gene in breast cancer.

DNA from 67 primary breast carcinoma biopsies has been examined for loss of heterozygosity (LOH) using the microsatellite (TA)n repeat marker positioned 1 kb upstream of the oestrogen receptor (ER) gene. Forty-seven (70.1%) of the cases were informative; nine of these (19.1%) were positive for LOH. In three of the nine cases, there was total loss, and in the other six cases there was a marked reduction in the intensity of signal from one allele. LOH correlated weakly with histological grade and age, but not with ER status. This result suggests that LOH of the ER gene does not have an important role in the lack of ER function in breast cancer tissues.

Base Sequence↗
PubMed1995

Transmission of multidrug-resistant serotype 23F Streptococcus pneumoniae in group day care: evidence suggesting capsular transformation of the resistant strain in vivo.

Surveillance for nasopharyngeal colonization with Streptococcus pneumoniae was maintained in a research day care center between 1985 and 1992. An outbreak of nasal carriage of a multi-drug-resistant (MDR) serotype 23F organism occurred between May 1990 and December 1991 involving 14 of 52 children. Electrophoresis of penicillin-binding proteins (PBP) and pulsed-field gel electrophoresis (PFGE) of chromosomal DNA indicated that the MDR serotype 23F organism was closely related to a serotype 23F MDR clone that has been prevalent in Spain since the early 1980s. In June 1991, an MDR serotype 14 organism was isolated from a child who had previously carried the MDR serotype 23F strain. PFGE and PBP typing revealed that the MDR serotype 14 organism was very similar to the circulating MDR serotype 23F strain, suggesting serotype transformation. Dissemination of MDR pneumococcal strains and possibly spread of the MDR phenotype to additional serotypes may be facilitated in group day care.

Anti-Bacterial Agents↗
PubMed1995

Methionine deficiency decreases protein accretion and synthesis but not tRNA acylation in muscles of chicks.

The effect of supplementing a methionine-deficient, isolated soy protein diet (0.5% total sulfur amino acids) with 0.2% D,L-methionine (DL-MET) or a molar equivalent of D,L-2-hydroxy-4-(methylthio) butanoic acid (DL-HMB) was assessed in chicks over an 8-d feeding study. Chicks consumed DL-HMB diet ad libitum (HIGH) or were restricted to the level consumed ad libitum by chicks fed the basal diet. The DL-MET diet was fed at the same two levels as the DL-HMB diet. Supplementing with either methionine source resulted in significantly greater growth rate, efficiency of feed conversion, and accretion and synthesis of protein in the gastrocnemius and pectoralis muscles. These increases were greater for chicks consuming feed ad libitum as compared with feed-restricted chicks and were not affected by methionine source. Rate of muscle protein degradation appeared to increase with supplementation of either methionine source, but only when feed intake was permitted to increase. The relative in vivo conversion of DL-HMB vs. D-MET to L-MET was similar in all groups as indicated by pool sizes of methionine, tRNA(met), and tRNA(cys), and rates of protein accretion and synthesis. These data demonstrate that dietary DL-HMB and DL-MET are used with similar efficacy to support skeletal muscle protein accretion and rates of protein synthesis when feed intake is equalized.

Acylation↗
PubMed1995

Heterogeneity in Li-Fraumeni families: p53 mutation analysis and immunohistochemical staining.

We have screened two families for constitutional TP53 mutations, one family with Li-Fraumeni syndrome and the other with features of this syndrome. We report a germline mutation in exon 7 of the TP53 gene in the family with "Li-Fraumeni-like" syndrome. The mutation occurred at codon 245 and causes a Gly-Ser amino acid change. It was inherited by both affected and unaffected subjects. Malignant tumours from all members of this family showed strong positive nuclear immunohistochemical staining with antibodies CM-1 and DO1, directed against TP53. In contrast, no constitutional TP53 mutations were found in a "classic" Li-Fraumeni family. In this family positive staining was seen in both malignant and normal tissues. These results support previous findings that variants of the Li-Fraumeni syndrome exist since not all LFS families carry TP53 germline mutations. Secondly, immunohistochemical positivity is not synonymous with an underlying mutation and is therefore inadequate as an exclusive diagnostic marker.

Adolescent↗
PubMed1995

A clinical evaluation of a resin-modified. Glass ionomer restorative material.

Compomers, resin-modified glass ionomers, were developed to improve the physical properties and clinical handling of glass ionomers. Compomers can be designed to be light-activated and used as restoratives or liners. This article reports data collected up to 12 months after placement of both compomer restorations and liners and is part of an ongoing study evaluating the performance of this material. Based on this data, the authors conclude that this new generation of light-activated glass-ionomer restoratives provides clinical results comparable to those recorded for composite resins at 12 months.

Acrylic Resins↗
PubMed1994

Problems with p53 immunohistochemical staining: the effect of fixation and variation in the methods of evaluation.

The availability of antibodies which recognise p53 protein in paraffin-embedded tissue has created the opportunity to use immunohistochemistry to study the expression of p53 in a wide variety of clinical material. In this paper we have investigated the relationship between the type of fixative and the pattern of p53 staining in mammary carcinoma. Optimal results were obtained from breast tissue fixed in phenol formol saline, methacarn or cold formol saline with positive staining for stabilised p53 protein occurring in 69/95 (73%) cases studied. Care must be taken in the interpretation of these results since positive staining for p53 protein is not always indicative of mutation of the p53 gene. Furthermore, a range of staining patterns is seen in mammary carcinomas, making interpretation difficult. Assessment of staining needs to be standardised in order that different studies can be compared. However, in breast carcinoma, p53 immunohistochemistry appears to give information relating to tumour grade and, independently, to prognosis.

Breast Neoplasms↗
PubMed1994

Confocal microscopic analysis of fluorescein compartmentation within crab urinary bladder cells.

Fluorescein (FL), a fluorescent organic anion, is compartmentalized in cells of organic anion-secreting epithelia, e.g., OK cells, teleost proximal tubule, and crab (Cancer borealis) urinary bladder, a proximal tubule analogue. To further examine the processes involved, FL uptake and distribution were studied in C. borealis urinary bladder cells using epifluorescence and laser confocal microscopy combined with video-image analysis. Intracellular FL was about evenly split between diffuse and punctate compartments after in vitro or in vivo loading. Treatments that affected FL transport into cells (incubation with p-aminohippuric acid or glutarate) altered the FL content of both compartments. However, nocodazole, a microtubule inhibitor, did not affect diffuse FL but significantly reduced punctate FL. Finally, confocal analysis indicated that individual sites of punctate FL accumulation moved in the secretory direction at 0.83 micron/min. Nocodazole nearly abolished this movement and significantly reduced transepithelial organic anion secretion. Thus, in crab urinary bladder, a substantial fraction of total cellular FL is sequestered in vesicles, and these vesicles move in the secretory direction, by a microtubule-dependent process.

Animals↗
PubMed1994

Evaluation of infiltrating ductal carcinomas with a DCIS component: correlation of the histologic type of the in situ component with grade of the infiltrating component.

Recently there has been an increase in the detection of DCIS, and there is much interest in establishing a new pathologic classification that has less subjective criteria than traditional methods and that more closely reflects the clinical behavior of the tumor. It is hoped that this will lead to a more rational approach to treatment of DCIS. In this study one such recently proposed classification has been applied to the DCIS component of 215 infiltrating ductal carcinomas, and this has been compared with the histologic grade of the tumors. There was a highly significant correlation between DCIS type and grade (chi 2 = 110.0, P < 0.0001); well- and intermediately differentiated DCIS were usually found in grade I and grade II tumors, respectively. Poorly differentiated DCIS was equally associated with grade II and grade III infiltrating carcinomas. Furthermore, in univariate analysis, the DCIS type correlated with disease-free (chi 2 = 17.1, P < 0.001) and overall survival (chi 2 = 13.97, P < 0.001). In a Cox multivariate analysis, which included histologic grade, the association between DCIS type and prognosis was lost because of the very close relationship between type and grade. These results support the validity of the new classification and reinforce the view that treatment of pure DCIS should be related to tumor type.

Adult↗
PubMed1993

c-erbB-2 amplification in mammary carcinoma.

The c-erbB-2 oncogene has been extensively studied in mammary carcinomas since Slamon and colleagues demonstrated the association between amplification and poor prognosis in 1987. Further work found that amplification was accompanied by overexpression of the protein; however, this relationship is not perfect. Recently, Hollywood and Hurst have shown increased transcription in some cell lines containing a single copy of the gene, causing mRNA accumulation in overexpressing cells. Protein expression appears to be a good indicator of various abnormalities in the c-erbB-2 gene. Fortunately, c-erbB-2 protein, unlike epidermal growth factor (EGF) receptor, survives most fixation procedures used in routine histopathology laboratories. This has enabled immunohistochemical studies to be carried out on archival material. A higher incidence of c-erbB-2 positivity occurs in ductal carcinoma in situ (DCIS) than in infiltrating carcinomas. In DCIS there is a very close association between protein expression and high grade (comedo type). This explains the very high incidence of c-erbB-2 positivity in Paget's disease of the nipple which is nearly always associated with high grade DCIS. A lower proportion of high grade infiltrating carcinomas express the protein, highlighting the difference in incidence of positivity in the two types of ductal lesion. As well as having a potential role in the biological classification of mammary carcinomas, c-erbB-2 expression has been used to predict response to treatment. There have been reports that tumors expressing c-erbB-2 fail to respond to either chemotherapy or endocrine therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Biomarkers, Tumor↗
PubMed1993

TGF alpha and TGF beta expression in mammary carcinoma.

TGF alpha and beta expression was examined using rabbit polyclonal antibodies and immunohistochemistry on a series of 195 breast carcinomas. TGF alpha immunoreactivity was observed in all but nine of the tumours, with over 50 per cent staining strongly. The polyclonal TGF alpha antibody (CIM1), when compared with a commercially available mouse monoclonal TGF alpha antibody used on the same sections, gave a good correlation (r = 0.52, P < 0.001). Both TGF alpha antibodies produced a granular cytoplasmic staining pattern, that with CIM1 being coarser, suggestive of binding to an aggregated protein or organelle. Eighty-one per cent of tumours stained with the TGF beta antibody, 35 per cent strongly. There was significant co-expression of TGF alpha and TGF beta (P < 0.001). However, they were not found to be useful prognostic indicators, lacking any significant correlation with histological classification, tumour size, nodal status, oestrogen receptor status, S-phase fraction, or overall survival over a 9-12 year period. The expression of these growth factors in most breast carcinomas suggests that they have important biological roles, but the exact nature of these roles remains unclear at the moment.

Adult↗
PubMed1993

Influence of Newcastle disease virus on the severity of Pasteurella anatipestifer infection in turkeys.

This study was designed to examine whether vaccine or virulent strains of Newcastle disease virus (NDV) would potentiate the disease caused by Pasteurella anatipestifer infection in turkeys. The studies were conducted in turkeys of two age groups. There were three experiments. In two experiments four-week-old turkeys were exposed either to vaccine or virulent strains of NDV after experimental P anatipestifer infection. In the third experiment 14-week-old turkeys were first exposed to virulent NDV and superimposed with P anatipestifer infection. In experiment 1, one bird died where P anatipestifer was given in combination with the vaccine strain of NDV. However, there was no difference in the clinical signs, gross lesions and histopathology compared with turkeys given P anatipestifer alone. In experiment 3 where turkeys received a virulent strain of NDV in combination with P anatipestifer, birds became dyspnoeic and showed signs of illness. There was a difference in the course of the disease, gross lesions and histopathology when compared with turkeys that received P anatipestifer only.

Animals↗
PubMed1993

Immunohistochemical detection of p53 protein in mammary carcinoma: an important new independent indicator of prognosis?

In an immunohistochemical pilot study of 195 primary breast cancer patients with a 10-year median follow-up we found that patients with carcinomas who express p53 protein in the majority of their tumor cells (19% of the cases) have a considerably worse prognosis than those who do not. The effect of the presence of the protein is seen on disease-free interval (chi-square, 11.69; P < .001), overall survival (chi-square, 19.68; P < .001), and survival after relapse (chi-square, 4.93; P < .02), and is seen in node-negative (chi-square, 6.99; P < .009) and node-positive (chi-square, 13.05; P < .001) patients. Furthermore, the effect is most apparent in patients with infiltrating lobular and grade II infiltrating ductal carcinomas (chi-square, 27.97; P < .001) that have a rather heterogeneous clinical behaviour and are difficult to subdivide on the basis of currently available markers. Cox multivariate analysis shows that p53 majority staining is second only to node status in significance of effect on overall survival.

Adult↗
PubMed1993

Immunochemical analysis of the p53 oncoprotein in matched primary and metastatic human tumours.

There is much interest in the range of genetic aberrations which occur in human malignancies. An immunohistochemical study has been carried out to investigate the consistency of expression of abnormally accumulated p53 protein in paired samples of archival primary and metastatic carcinomas. The staining of methacarn-fixed tissue from 136 matched pairs of mammary carcinoma and 20 cancers from other sites was completed using antibody CM-1 and DO1 in a sensitive peroxidase-conjugated streptavidin-biotin technique. The majority of tumour cells were positive in 25% and the tumours were negative in 17% of the primary carcinomas; staining was heterogeneous in the remaining cases. Staining was identical in 180/186 (96%) metastatic lesions. An ELISA assay carried out on 12 matched pairs of the tumour specimens demonstrated that altered conformation of the aberrant p53 protein present in a primary lesion was maintained in its metastasis. These data indicate that alterations in the p53 gene result in a relatively stable phenotype and that progression of disease is not usually accompanied by either further mutation or loss of the mutant allele.

Breast Neoplasms↗
PubMed1993

Ki-S1, a novel proliferative marker: flow cytometric assessment of staining in human breast carcinoma cells.

There is considerable interest in immunohistochemical markers of proliferation which are suitable for use on routinely fixed clinical material. The novel proliferation-associated antibody Ki-S1 shows promise in this respect. In this study we have: (i) defined the pattern of Ki-S1 labelling relative to the cell cycle phase; (ii) investigated the labelling pattern with Ki-S1 on a human breast cell line (ZR75) under varying proliferative conditions induced by serum deprivation and refeeding; (iii) examined in a flow cytometric study Ki-S1 staining in archival, clinical breast carcinoma samples. In exponentially growing cells Ki-S1 showed a marked cell cycle phase-specific variation in staining intensity which increased linearly through the S-phase, was high in G2 and reached its peak in mitosis. Ki-S1 staining intensity mirrored the changes in proliferative activity of ZR75 cells during serum deprivation and refeeding. In a small series of human breast carcinoma, Ki-S1 staining intensity correlated with S-phase fraction (SPF) derived from DNA profiles. The antigen labelled by Ki-S1 is extremely robust, resisting degradation by fixation and by an aggressive enzymic tissue disaggregation method. Ki-S1 warrants further investigation as a proliferation-related marker, particularly for routine clinical application.

Animals↗
PubMed1993

Comparison between p53 staining in tissue sections and p53 proteins levels measured by an ELISA technique.

We studied 51 paired samples of tissue sections and cytosol extracts from patients with breast cancer. A very high affinity monoclonal antibody to human p53 protein, DO-1, and polyclonal serum CM-1 to p53 protein were used for two site ELISA assays and CM-1 was used for immunohistochemistry to detect p53 protein accumulation in breast cancer samples. Eighteen carcinomas were positive for p53 by tissue staining and ELISA assay. Nineteen tumours were negative by ELISA and immunohistochemistry, and 14 cases with low levels of positive staining by immunohistochemistry were negative by the ELISA assay. A statistically significant correlation has been found between the degree of staining and the amount of p53 protein measured by ELISA (Pearson's correlation coefficient r = 0.59, P < 0.00001). Our ELISA assay offers an alternative approach to evaluating the p53 status of breast biopsy material, using cytosol extracts routinely prepared for steroid hormone receptor assays. This assay should also be of general application to other situations where the level of p53 protein needs to be determined.

Breast Neoplasms↗
PubMed1993

p53 immunoreactivity in human malignant melanoma and dysplastic naevi.

Expression of the tumour suppressor protein, p53, was determined in 77 cutaneous melanocytic lesions, and in five lymph node metastases from malignant melanoma, in an immunohistochemical study employing CM-1, an antiserum raised against recombinant human p53 protein. Because wild-type p53 protein is rapidly degraded in normal cells, p53 immunoreactivity suggests the presence of an abnormally stable p53 protein. This may occur through either post-translational mechanisms or gene mutation. A highly significant correlation was found between p53 immunoreactivity and malignancy in melanocytic lesions (P < 0.0001). Overall, p53 immunoreactivity was observed in 63% of tumour specimens examined, but not in benign melanocytic naevi, although occasional foci of weak nuclear p53 immunoreactivity were observed in a minority of dysplastic naevi and a solitary Spitz naevus. A significant correlation was also found between strong p53 immunoreactivity and malignant melanomas associated with a poor prognosis (P = 0.008). These data suggest an important role for p53 tumour suppressor protein in the biology of human cutaneous malignant melanoma.

Dysplastic Nevus Syndrome↗
PubMed1993

Comparison of three cell cycle associated antigens as markers of proliferative activity and prognosis in breast carcinoma.

The staining patterns obtained with two antibodies against proliferating cell nuclear antigen (PC10 and 19A2) and another cell cycle associated antibody (KiS1) were compared with each other and with a number of established prognostic markers of breast carcinoma. Although PC10 and 19A2 staining patterns were similar, only the latter was significantly associated with KiS1 antibody staining. These findings suggest that the two PCNA antibodies detect different epitopes. KiS1 was the only antibody to show an association with S phase fraction measured by flow cytometry (p < 0.001). It was also associated with histological grade (p = 0.003), oestrogen receptors (p = 0.045), and DNA index (p = 0.007). PC10 showed no association with any of the markers of prognosis, while 19A2 was associated with histological grade (p = 0.017) and oestrogen receptors (p = 0.043). The two PCNA antibodies do not seem to be of value in measuring proliferative activity nor do they seem to be associated with established markers of prognosis in breast cancer.

Antibodies, Neoplasm↗