Biomedical subjects

E Pinney

Publications and source records attributed to E Pinney.

At least 19 recordsLinked to original sources

PubMed2003

Breast density and breast cancer risk factors in a high-risk population.

This study investigates relationships between familial and hormonal risk factors and breast density in women at high risk of developing breast cancer. The subjects are a subset of 102 women from the international breast cancer intervention study (IBIS), for whom a series of repeated measurements of breast density were available. Details of familial and hormonal risk factors for breast cancer were collected at entry and multivariate ordered logistic regression used to identify risk factors for increased breast density. Lower body mass index and nulliparity were associated with high breast density, whereas smoking was associated with lower breast density. It is not yet known whether a reduction in breast density will lead to a corresponding reduction in breast cancer risk, so we propose that changes in breast density be investigated as a potential early indicator of efficacy in chemoprevention trials for breast cancer.

Body Mass Index↗

PubMed2000

Human three-dimensional fibroblast cultures express angiogenic activity.

Human neonatal fibroblasts were cultured on a lactate-glycollate copolymer scaffold for 12-16 days to form a three-dimensional dermal equivalent tissue. The cellular content of vascular endothelial growth factor (VEGF) mRNA in these three-dimensional cultures was 22-fold greater than that observed in the same fibroblasts grown as monolayers. No induction was shown by hepatocyte growth factor (HGF) or angiopoietin 1 indicating that the effect was specific to VEGF. The predominant VEGF splice variant, detected by RT-PCR corresponded to the 121 amino acid form, with less of the 165 amino acid form. The cell-associated forms (189 and 206 amino acids) comprised less than 1% of the total VEGF mRNA. VEGF and HGF proteins, determined by ELISA, were secreted in physiologically significant amounts, 0.5-4 ng per 24 h/10(6) cells. Conditioned medium from the three-dimensional cultures stimulated proliferation of endothelial cells in a dose-dependent manner and induced cellular expression of integrin alpha(v)beta(3). Conditioned medium from the same dermal fibroblasts cultured in monolayer showed little angiogenic activity in any of these assays. Using the chorioallantoic membrane (CAM) angiogenesis assay, the cultures stimulated blood vessel production 2.8-fold over scaffold alone. VEGF-neutralizing antibody reduced the vessel development in the CAM to the level in the scaffold control. Anti-HGF antibody had no significant effect. In conclusion, three-dimensional cultures of dermal equivalent tissue express angiogenic activity to a greater extent than monolayer cultures, some of which can be assigned to VEGF.

Allantois↗

PubMed2000

Teaching non-specialist health care professionals how to identify the atypical mole syndrome phenotype: a multinational study.

The atypical mole syndrome (AMS) phenotype is the strongest known risk factor for cutaneous melanoma but recognition of the phenotype has been claimed to be problematic and to require specialist assessment. This study determined the ability of previously unskilled doctors and nurses in five countries to recognize the phenotype after brief training. The system used was the AMS scoring system. This incorporates melanocytic naevus counts, clinical atypia of naevi and distribution of naevi. The agreement in scoring between the dermatologist and trained personnel was determined in 986 patients; overall agreement in diagnosis was 94.5% (kappa 0.70, P < 0.0001). The kappa scores in different countries ranged from 0.65 to 0.77 for individual naevus characteristics, indicative of good agreement. Accurate diagnosis of the atypical mole syndrome phenotype is possible by non-specialists. This has implications for collaborative studies of naevi, for screening and for both primary and secondary prevention of melanoma.

Adolescent↗

PubMed2000

Genotype/phenotype and penetrance studies in melanoma families with germline CDKN2A mutations.

Patients with a family history of melanoma are at increased risk of this tumor. Those family members who also have the atypical mole syndrome are commonly targeted for screening in the belief that they are more likely to be mutant gene carriers. We have correlated the atypical mole syndrome phenotype and gene carrier status in five families with germline CDKN2A mutations and shown that family members with the atypical mole syndrome were three times more likely to be mutant gene carriers than their relatives who did not have the atypical mole syndrome (odds ratio 3.4; confidence interval 1.0-11. 1), supporting the view that CDKN2A is nevogenic. Individual characteristics which best predicted mutant gene carrier status were: nevi on the buttocks (odds ratio 4.4; confidence interval 1. 6-12.4), nevi on the feet (odds ratio 4.2; confidence interval 1. 4-12.5), total nevus number being at least 100 (nevi > or = 2 mm in diameter) (odds ratio 3.4; confidence interval 1.0-11.1) and two or more clinically atypical nevi (odds ratio 3.1; confidence interval 1. 1-9.0). Gene carriers were also significantly more likely to have noticeable freckling and possibly also Fitzpatrick skin types 1-3. The overlap between gene carriers and nongene carriers was, however, marked: the atypical mole syndrome did not clearly differentiate mutant gene carriers from those with a normal gene. This study is of significance to clinicians as the clinical practice of using the atypical mole syndrome to identify particular family members for surveillance is shown to be inappropriate. Until formal gene testing is available, all members of families with an excessive number of melanoma cases should be treated as potential mutation carriers at increased risk of melanoma.

Genes, p16↗

PubMed2000

Hand washing.

What could be more basic than the simple act of washing your hands? Children at junior school are taught to do it. Yet research tends to point to the lack of hand washing as being a major contributor to hospital acquired infection. I have summarised this piece by Elizabeth Pinney which takes us right back to the 18th century--and bang up to date! Reflect on your practices and that of your colleagues before you tell me this is old news.

Cross Infection↗

PubMed1998

Melanoma excision by general practitioners in north-east Thames region, England.

A retrospective study of pathology reports of melanomas excised by general practitioners (GPs) was undertaken in the course of a population-based study of melanoma, with a telephone survey of the current practice of those GPs who had excised melanomas. The objectives of this study were to identify all cases of cutaneous melanoma excised by GPs in the North-East Thames Region between 1989 and 1993, and to review the management of those patients. The main outcome measures of the study were: (i) the patterns of distribution of GP excisions within the region; (ii) the histological subtypes of melanomas excised, the accuracy of the pre-excision clinical diagnosis and the adequacy of treatment of the GP-treated tumours compared with the control group; and (iii) the reported current practice in the management of pigmented skin lesions by the GPs who had excised melanomas. Eight hundred and nineteen melanomas were excised in the region during the study period, of which 59 were excised by GPs. The Breslow thickness of tumours was similar in both GP-excised and non-GP-excised groups. Tumours were more likely to be amelanotic in the GP-excised group (P < 0.001). Incomplete excision was significantly more likely in the GP group (P < 0.001). The GPs made a confident clinical diagnosis of melanoma in only 17% of patients prior to surgery. The reported referral rate to specialists by this subset of GPs of patients with pigmented lesions was low, and at interview half of the GPs reported that they felt confident enough to manage patients with suspected skin cancers on their own. The majority of the GPs did not routinely obtain histological examination of skin lesions they believed to be benign. In conclusion, there are problems with the accuracy of clinical diagnosis and inadequacy of excision of melanomas removed in primary care. In the majority of cases, however, patients were subsequently appropriately treated by referral to specialist units. There was an under-usage of pathological examination of samples by the GPs interviewed.

Ambulatory Surgical Procedures↗

PubMed1998

Three-dimensional fibroblast culture implant for the treatment of diabetic foot ulcers: metabolic activity and therapeutic range.

Dermagraft is three-dimensional, allogeneic, human neonatal dermal fibroblast culture grown on a degradable scaffold and cryopreserved. Clinical trials for treatment of diabetic foot ulcers showed optimal healing within a therapeutic range of metabolic activity, determined by 3[4,5-dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide (MTT) reduction. Actions of Dermagraft in wound repair include colonization by cells and provision of growth factors and cytokines, both activities dependent on living cells. Cells in the cryopreserved culture showed 60% viability by dye exclusion and, when isolated, were able to proliferate in monolayer culture. Protein synthesis by Dermagraft was inhibited 70-98% by cryopreservation, but, if within the therapeutic range, recovered to 45-85% of the prefreeze value over 48 h. Subtherapeutic Dermagraft showed variable, low recovery. Expression of mRNA for vascular endothelial growth factor (VEGF), platelet-derived growth factor A chain, and insulin-like growth factor-1 was reduced >83% in subtherapeutic compared with therapeutic Dermagraft. Granulocyte colony-stimulating factor and VEGF protein secretion, determined by enzyme-linked immunosorbent assay (ELISA), and angiogenic activity also depended on therapeutic range. VEGF secretion dropped sharply with MTT reductase in subtherapeutic tissue. The data demonstrate the critical dependence of the therapeutic properties of this living dermal implant on recovery of protein synthesis, growth factor expression, and angiogenesis, determined by metabolic activity.

Animals↗

PubMed1997

Germline mutations of the CDKN2 gene in UK melanoma families.

Germline mutations in CDKN2 on chromosome 9p21, which codes for the cyclin D kinase inhibitor p16, and more rarely, mutations in the gene coding for CDK4, the protein to which p16 binds, underlie susceptibility in some melanoma families. We have sequenced all exons of CDKN2 and analysed the CDK4 gene for mutations in 27 UK families showing evidence of predisposition to melanoma. Five different germline mutations in CDKN2 were found in six families. Three of the mutations (Met53Ile, Arg24Pro and 23ins24) have been reported previously. We have identified two novel CDKN2 mutations (88delG and Ala118Thr) which are likely to be associated with the development of melanoma, because of their co-segregation with the disease and their likely functional effect on the CDKN2 protein. In binding assays the protein expressed from the previously described mutation, Met53Ile, did not bind to CDK4/CDK6, confirming its role as a causal mutation in the development of melanoma. Ala118Thr appeared to be functional in this assay. Arg24Pro appeared to bind to CDK6, but not to CDK4. No mutations were detected in exon 2 of CDK4, suggesting that causal mutations in this gene are uncommon. The penetrance of these mutant CDKN2 genes is not yet established, nor is the risk of non-melanoma cancer to gene carriers.

Adult↗

PubMed1996

Risk of cutaneous melanoma in relation to the numbers, types and sites of naevi: a case-control study.

The atypical mole syndrome (AMS) phenotype, characterised by a large number of common naevi as well as atypical naevi, has been described in families with a genetic susceptibility to melanoma. However, the importance of this phenotype for melanoma in the general population has not been conclusively determined. This study was designed to examine the types and distribution of naevi as well as the prevalence of the AMS phenotype in melanoma patients in England compared with controls. A total of 426 cutaneous melanoma cases (61% of all incident cases) aged 16-75 years were recruited between 1989 and 1993 from the north-east Thames region of the UK and 416 controls from the same age group were recruited over the same period and from the same region. Each subject answered a questionnaire covering demographic details, sun exposure history and other risk factors and underwent a skin examination with total body naevus count performed by a dermatologist. The AMS phenotype was defined using a scoring system. Atypical naevi gave the highest relative risk for cutaneous melanoma, with an odds ratio (OR) of 28.7 (P < 0.0001) for four or more atypical naevi compared with none. Many common naevi were also an important risk factor: the OR for 100 or more naevi 2 mm or above in diameter compared with 0-4 naevi was 7.7 (P < 0.0001). Melanoma was also associated with naevi on sun-exposed sites but also with naevi on non-sun-exposed sites such as the dorsum of the feet, buttocks and anterior scalp. Sixteen per cent of the cases had the AMS phenotype compared with 2% of the controls (OR 10.4, P < 0.0001). The AMS phenotype was more common in males than females (P = 0.008). The odds ratio for the presence of the AMS phenotype was dependent on age, with an odds ratio of 16.1 (95% CI 4.6-57.5) for the presence of the AMS phenotype if aged less than 40 compared with an odds ratio of 6.9 (95% CI 2.9-16.6) if aged 40 or more. The AMS phenotype was strongly predictive of an increased risk of melanoma outside the familial context.

Adolescent↗

PubMed1994

Filipin-sensitive caveolae-mediated transport in endothelium: reduced transcytosis, scavenger endocytosis, and capillary permeability of select macromolecules.

Caveolae or noncoated plasmalemmal vesicles found in a variety of cells have been implicated in a number of important cellular functions including endocytosis, transcytosis, and potocytosis. Their function in transport across endothelium has been especially controversial, at least in part because there has not been any way to selectively inhibit this putative pathway. We now show that the ability of sterol binding agents such as filipin to disassemble endothelial noncoated but not coated plasmalemmal vesicles selectively inhibits caveolae-mediated intracellular and transcellular transport of select macromolecules in endothelium. Filipin significantly reduces the transcellular transport of insulin and albumin across cultured endothelial cell monolayers. Rat lung microvascular permeability to albumin in situ is significantly decreased after filipin perfusion. Conversely, paracellular transport of the small solute inulin is not inhibited in vitro or in situ. In addition, we show that caveolae mediate the scavenger endocytosis of conformationally modified albumins for delivery to endosomes and lysosomes for degradation. This intracellular transport is inhibited by filipin both in vitro and in situ. Other sterol binding agents including nystatin and digitonin also inhibit this degradative process. Conversely, the endocytosis and degradation of activated alpha 2-macroglobulin, a known ligand of the clathrin-dependent pathway, is not affected. Interestingly, filipin appears to inhibit insulin uptake by endothelium for transcytosis, a caveolae-mediated process, but not endocytosis for degradation, apparently mediated by the clathrin-coated pathway. Such selective inhibition of caveolae not only provides critical evidence for the role of caveolae in the intracellular and transcellular transport of select macromolecules in endothelium but also may be useful for distinguishing transport mediated by coated versus noncoated vesicles.

Animals↗

PubMed1994

Genetic heterogeneity in familial malignant melanoma.

Following reports of linkage to chromosome 9p in families with malignant melanoma, we have been studying a series of UK families. Six families were selected with three or more cases of malignant melanoma. We have used a total of twelve markers mapping in the interval 9p13-p23 and constructed a set of haplotypes to study the inheritance of the disease chromosome. Of the six families, three were consistent with linkage to the short arm of 9, although their limited size precluded confirmation of linkage. One family was clearly unlinked, one family was either unlinked, or contains a sporadic case, or delimits the location of the melanoma gene, and one family was essentially uninformative. This is strong evidence for genetic heterogeneity in families with the malignant melanoma phenotype. We have also sequenced exon 2 of the recently identified candidate tumour suppressor gene, p16, in six individuals and found no evidence for germline mutations in this region of the p16 gene in our families with inherited malignant melanoma.

Adolescent↗

PubMed1994

Family studies in melanoma: identification of the atypical mole syndrome (AMS) phenotype.

Thirteen families have been studied clinically as the basis for a linkage study of susceptibility to cutaneous melanoma. Previous studies have shown that a number of families with predisposition to melanoma have abnormal naevi, now known as the atypical mole syndrome (AMS) phenotype. Many groups performing linkage studies using families selected from geographical areas with higher rates of melanoma have concentrated on the diagnosis of melanoma to identify presumptive gene carriers. In the UK, in the absence of extended families with multiple cases of melanoma, we have attempted to identify gene carriers through the presence of the AMS phenotype. Previously the AMS phenotype has been poorly defined and so we have developed a scoring system to define the AMS in an attempt to allow for variation in expression among gene carriers. In this report, we document the clinical characteristics of all 13 families and the use of our scoring system. The pattern of inheritance within these selected families of the AMS phenotype with or without melanoma is consistent with a dominant gene.

Analysis of Variance↗

PubMed1993

Five cases of coexistent primary ocular and cutaneous melanoma.

BACKGROUND: Patients with the atypical mole syndrome are prone to cutaneous melanoma, but their risk of ocular melanoma has not been established. We studied the skin of 207 consecutive patients with eye melanoma referred to Moorfields Hospital in London, England, in an attempt to determine what percentage of these patients had the atypical mole syndrome phenotype. OBSERVATIONS: Five patients were seen who had primary melanomas of both the eye and the skin. In three of these patients, the cutaneous melanomas were discovered only as a result of this study. The number of cutaneous melanomas expected in this cohort of patients with eye melanomas was no more than 0.4 on the basis of the United Kingdom incidence of both tumors. This difference was highly significant. CONCLUSIONS: The occurrence of primary cutaneous melanoma in five patients from a cohort of 207 patients with eye melanoma (or the premalignant melanocytic lesion of the conjunctiva called "primary acquired melanosis") provides strong evidence of an association between cutaneous and ocular melanoma. Three of the five patients also had the atypical mole syndrome phenotype, suggesting that the atypical mole syndrome predisposes to both types of melanoma.

Adult↗

PubMed1992

Quantitation of specific binding of orosomucoid to cultured microvascular endothelium: role in capillary permeability.

Orosomucoid (also known as alpha 1-acid glycoprotein) is a highly sialylated, polyanionic serum glycoprotein. Its presence in vascular perfusates alters microvascular permeability, presumably by binding to the endothelial glycocalyx, but the rest of its functions remains unknown. In this study, we assess the binding of bovine serum orosomucoid (BSO) to the surface of bovine pulmonary microvascular endothelial cells (BLMVEC) in culture at 4 degrees C. The binding of radioiodinated BSO (125I-BSO) reached equilibrium after 10 min of incubation, was not calcium dependent, and was reversible by greater than 80% in 30 min. The binding of 125I-BSO was competed with unlabeled BSO but not by transferrin, immunoglobulin, gelatin, ovalbumin, mannan, fucoidan, mucin, or asialomucin. In addition, binding was not affected by the presence of galactose, glucose, fucose, mannose, N-acetyl-D-galactosamine, or N-acetyl-D-glucosamine. This binding behavior is not consistent with carbohydrate recognition by lectin-like molecules such as the asialoglycoprotein receptor. Scatchard analysis of the BSO binding to BLMVEC produced a concave-upward shaped curve, which revealed a higher affinity binding component with an apparent equilibrium affinity constant (Kd) of 8.6 nM and a maximum receptor number of 40,000/cell and revealed a moderate affinity component with a Kd of 9.1 microM with a maximum binding of 10(7) binding sites per cell. Other blood vessel-associated cells clearly bound less BSO with a lower binding affinity than the BLMVEC monolayers. From the binding data, we estimated the total increase in the negative charge of the glycocalyx with orosomucoid binding to be approximately 17 meq/l.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

Surface glycoconjugates of cynomolgus monkey trabecular cells.

Non-ionic detergent-soluble and detergent-resistant cynomolgus monkey trabecular cell surface glycoconjugates have been identified using three radiolabeling procedures and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. The cell surface glycoconjugates were radiolabeled with tritiated sodium borohydride after treatment with: (1) neuraminidase/galactose oxidase; (2) galactose oxidase; or (3) sodium metaperiodate. The non-ionic detergent soluble components were removed by treatment of the monolayer cell culture with 1% Triton X-100 in hypotonic buffer. The radiolabeled trabecular cell surface glycoconjugates in the Triton X-100 soluble and insoluble fractions were resolved by sodium dodecyl sulfate polyacrylamide gel electrophoresis under reducing conditions and visualized by fluorography. Treatment of the monkey trabecular cells with neuraminidase/galactose oxidase/tritiated sodium borohydride resulted in the radiolabeling of five components ranging in apparent molecular weight from 128,000 to 39,000 in the Triton X-100 soluble fractions, while 12 radiolabeled glycoconjugates with apparent molecular weights ranging from 240,000 to 26,000 were resolved in the Triton X-100 resistant fraction.

Animals↗

PubMed1988

Trauma peptide induction of lymphocyte changes predictive of sepsis.

Post-trauma immunosuppression is characterized by T-cell subpopulation changes and the presence of a low molecular weight suppressive active peptide (SAP), which suppresses T-cell blastogenesis and neutrophil chemotaxis. This study evaluated post-trauma T-cell antigens and suppressive active peptide/T-cell interactions to determine if the suppressive active peptide concentrations predictive of sepsis can cause changes in antigen expression predictive of sepsis. Human lymphocyte markers and differentiation antigens were analyzed post-trauma using flow cytometry for markers predictive of sepsis. Changes induced by purified suppressive active peptide incubated with normal human lymphocytes were similarly analyzed by flow cytometry. SAP concentrations for incubation were chosen which correlated with concentrations in patients developing clinical sepsis. Significant T-cell changes in patients who developed sepsis include: decreased total T-cells, decreased helper cells, decreased natural killer cells, increased Ia expressing mononuclear cells, increased activated T-cells, (L22) and increased IL-2 expressing cells (TAC). Suppressive active peptide can activate T-cells and cause significant increased expression of IL-2 receptors and natural killer cells. Other T-cell changes following trauma predictive of sepsis seem to occur independent of in vitro incubation with suppressive active peptides. IL-2 expressing cells are known to be more readily suppressed by the suppressive peptide. Suppressive peptide activation and subsequent inhibition of T-cells suggests a potential way to explain suppressive peptide-induced immunosuppression following trauma.

Adult↗

PubMed1988

Elastase and suppressor active peptide activity following burn injury.

Proteolytic enzyme activity following trauma and inflammation plays a key role in the pathophysiology of injury. The precise mechanisms involved in the induction of protease release has not been determined. We show here that sera from burn patients with greater than 40% TBSA have significantly elevated levels of active elastase which correspond with significantly increased levels of suppressor active peptide (SAP) and suppression of neutrophil chemotaxis. The elastase inhibitory capacity of serum from burned or blunt trauma patients was within normal range, suggesting that the primary elastase inhibitor, alpha-1-proteinase inhibitor, is functionally active. Additionally, granulocytes exposed to suppressor active peptide in vitro resulted in a markedly elevated release of elastase into the culture supernatants. These data suggest that the suppressor peptide is capable of not only suppressing immune function but is also a potent mediator for the induction of proteolytic enzyme release from leukocytes.

Burns↗

PubMed1988

Isolation of an immunosuppressive trauma peptide and its relationship to fibronectin.

The purpose of this study was to characterize a suppressive active glycopeptide (SAP) using affinity chromatography (AFFI) and explore its similarity to fibronectin (FN) degradation products. It is postulated that SAP is a degradation fragment of a large serum-borne protein, possibly FN. Human trauma serum (HTS) and elastase-degraded human FN were run over an AFFI prepared with monoclonal antibody to SAP. Bound protein was eluted with 2M NaCl and dialyzed to remove salt. Immunosuppressive activity of HTS and FN eluates was monitored using inhibition of neutrophil chemotaxis (CTX). Active fractions were compared to the starting material and controls with 15% PAGE. AFFI eluates of HTS revealed a high molecular weight protein band (450 kd) with no inhibitory CTX activity and singular low molecular weight protein (LMW) band (less than 20,000) with 93% +/- 5% CTX suppression. Elastase-digested purified human FN eluates run under identical conditions over the same AFFI revealed two bands with an identical elution profile as HTS eluates. CTX suppression 95 +/- 5% was seen only with the LMW band. Incubation of enriched LWF fragments of digested FN and HTS with whole FN reversed CTX suppression. This suggests affinity purification of a single LMW suppressive glycopeptide which may bind to or be a degradation product of plasma or cellular fibronectin.

Chemotaxis, Leukocyte↗