PubMed Health⌕ Search

Biomedical subjects

I Ellis

Publications and source records attributed to I Ellis.

At least 19 recordsLinked to original sources

Novel cationic trypsinogen (PRSS1) N29T and R122C mutations cause autosomal dominant hereditary pancreatitis.

Hereditary pancreatitis (HP) is usually caused by mutations in the cationic trypsinogen (PRSS1) gene, especially R122H or N29I. We sequenced the PRSS1 gene in the proband of families without these common mutations. Novel R122C and N29T mutations were detected in independent families that segregated with the disease in an autosomal dominant fashion. The R122C mutation eliminates the arginine autolysis site as with R122H mutations. The N29T mutation may also enhance intrapancreatic trypsin activity as has been demonstrated in vitro. Identification of these new mutations requires special attention as commonly used detection methods may fail.

Adult↗

The N34S mutation of SPINK1 (PSTI) is associated with a familial pattern of idiopathic chronic pancreatitis but does not cause the disease.

BACKGROUND: Mutations in the PRSS1 gene explain most occurrences of hereditary pancreatitis (HP) but many HP families have no PRSS1 mutation. Recently, an association between the mutation N34S in the pancreatic secretory trypsin inhibitor (SPINK1 or PSTI) gene and idiopathic chronic pancreatitis (ICP) was reported. It is unclear whether the N34S mutation is a cause of pancreatitis per se, whether it modifies the disease, or whether it is a marker of the disease. PATIENTS AND METHODS: A total of 327 individuals from 217 families affected by pancreatitis were tested: 152 from families with HP, 108 from families with ICP, and 67 with alcohol related CP (ACP). Seven patients with ICP had a family history of pancreatitis but no evidence of autosomal dominant disease (f-ICP) compared with 87 patients with true ICP (t-ICP). Two hundred controls were also tested for the N34S mutation. The findings were related to clinical outcome. RESULTS: The N34S mutation was carried by five controls (2.5%; allele frequency 1.25%), 11/87 (13%) t-ICP patients (p=0.0013 v controls), and 6/7 (86%) affected (p<0.0001 v controls) and 1/9 (11%) unaffected f-ICP cases. N34S was found in 4/108 affected HP patients (p=0.724 v controls), in 3/27 (11%) with wild-type and in 1/81 (1%) with mutant PRSS1, and 4/67 ACP patients (all p>0.05 v controls). The presence of the N34S mutation was not associated with early disease onset or disease severity. CONCLUSIONS: The prevalence of the N34S mutation was increased in patients with ICP and was greatest in f-ICP cases. Segregation of the N34S mutation in families with pancreatitis is unexplained and points to a complex association between N34S and another putative pancreatitis related gene.

Adult↗

Analysis of short stature homeobox-containing gene ( SHOX) and auxological phenotype in dyschondrosteosis and isolated Madelung deformity.

Dyschondrosteosis (DCO; also called Léri-Weill syndrome) is a skeletal dysplasia characterised by disproportionate short stature because of mesomelic shortening of the limbs. Madelung deformity is a feature of DCO that is distinctive, variable in expressivity and frequently observed. Mutations of the SHOX (short stature homeobox-containing) gene have been previously described as causative in DCO. Isolated Madelung deformity (IMD) without the clinical characteristics of DCO has also been described in sporadic and a few familial cases but the genetic defect underlying IMD is unknown. In this study, we have examined 28 probands with DCO and seven probands with IMD for mutations in the SHOX gene by using polymorphic CA-repeat analysis, fluorescence in situ hybridisation (FISH), Southern blotting, direct sequencing and fibre-FISH analyses. This was combined with auxological examination of the probands and their family members. Evaluation of the auxological data showed a wide intra- and interfamilial phenotype variability in DCO. Out of 28 DCO probands, 22 (79%) were shown to have mutations in the SHOX gene. Sixteen unrelated DCO families had SHOX gene deletions. Four novel DCO-associated mutations were found in different families. In two additional DCO families, the previously described nonsense mutation (Arg195Stop) was detected. We conclude that mutations in the SHOX gene are the major factor in the pathogenesis of DCO. In a female proband with severe IMD and her unaffected sister, we detected an intrachromosomal duplication of the SHOX gene.

Blotting, Southern↗

The mutational spectrum of human malignant autosomal recessive osteopetrosis.

Human malignant infantile osteopetrosis (arOP; MIM 259700) is a genetically heterogeneous autosomal recessive disorder of bone metabolism, which, if untreated, has a fatal outcome. Our group, as well as others, have recently identified mutations in the ATP6i (TCIRG1) gene, encoding the a3 subunit of the vacuolar proton pump, which mediates the acidification of the bone/osteoclast interface, are responsible for a subset of this condition. By sequencing the ATP6i gene in arOP patients from 44 unrelated families with a worldwide distribution we have now established that ATP6i mutations are responsible for approximately 50% of patients affected by this disease. The vast majority of these mutations (40 out of 42 alleles, including seven deletions, two insertions, 10 nonsense substitutions and 21 mutations in splice sites) are predicted to cause severe abnormalities in the protein product and are likely to represent null alleles. In addition, we have also analysed nine unrelated arOP patients from Costa Rica, where this disease is apparently much more frequent than elsewhere. All nine Costa Rican patients bore either or both of two missense mutations (G405R and R444L) in amino acid residues which are evolutionarily conserved from yeast to humans. The identification of ATP6i gene mutations in two families allowed us for the first time to perform prenatal diagnosis: both fetuses were predicted not to be affected and two healthy babies were born. This study contributes to the determination of genetic heterogeneity of arOP and allows further delineation of the other genetic defects causing this severe condition.

Amino Acid Sequence↗

Information and support needs of women with primary relatives with breast cancer: development of the Information and Support Needs Questionnaire.

AIMS OF THE STUDY: The aim was to develop and pilot test a newly developed measure, The Information and Support Needs Questionnaire (ISNQ), for use with women with primary relatives with breast cancer. BACKGROUND/RATIONALE: Breast cancer is a major risk to the health of women in the United Kingdom (UK). Increasingly, research is documenting women's needs for information and support, particularly at the time of diagnosis. However, to date there is little understanding of the information and support needs of women who have a family history of breast cancer. Contributing to the dearth of understanding of female relatives' needs is the lack of valid and reliable instruments for use in descriptive and intervention research with this population. DESIGN/METHODS: The ISNQ and survey items documenting family history, sources of information and support for breast cancer risk, breast self-care practices, and other variables were pilot tested for the acceptability of the measures, appropriateness of the data collection methods, initial psychometric properties of the ISNQ, and time and financial costs of administration. Data were collected from 39 women living in the North-west of England who had primary relatives with breast cancer using mailed questionnaires and follow-up telephone interviews. FINDINGS: The items on the ISNQ were reported to be clear, acceptable to women and to yield relevant data. The psychometric properties of the new measure were satisfactory with a high reliability coefficient alpha. Descriptive findings indicate that women had moderate to high needs for information and support, but reported that these needs were not well met. CONCLUSIONS: The results of this pilot are guiding the development of a larger study in which the information and support needs of women with a family history of breast cancer are explored.

Adult↗

Predictive genetic testing in maturity-onset diabetes of the young (MODY).

INTRODUCTION: Maturity-onset diabetes of the young (MODY) is characterized by autosomal dominant inheritance of young-onset non-insulin-dependent diabetes. It accounts for approximately 1% of Type 2 diabetes (approximately 20 000 people in the UK). Diagnostic and predictive genetic tests are now possible for 80% of MODY families. Diagnostic tests can be helpful as the diagnosis can be confirmed and the subtype defined which has implications for treatment and prognosis. However predictive genetic testing, particularly in children, raises many scientific, ethical and practical questions. METHODS: This is a case report of a family with diabetes resulting from an hepatic nuclear factor (HNF)1alpha mutation, who request a predictive test in their 5-year-old daughter. The scientific issues arising from molecular genetic testing in MODY are discussed, along with the process of genetic counselling. The views of the family and the clinical genetics team involved are presented. RESULTS: The implications of positive and negative predictive test results and the possibility of postponing the test were among many issues discussed during genetic counselling. The family remained convinced the test was appropriate for their daughter and the clinical genetics team fully supported this decision. The family, motivated by their family history of diabetes and personal experiences of the disease, wished to reduce uncertainty about their daughter's future irrespective of the result. CONCLUSIONS: This case emphasizes that decisions on predictive testing are very personal and require appropriate counselling.

Adolescent↗

A new polymorphism for the RI22H mutation in hereditary pancreatitis.

BACKGROUND AND AIMS: Hereditary pancreatitis (HP) is a rare form of recurrent acute and chronic pancreatitis. Mutations in the cationic trypsinogen (protease serine 1, PRSS1) gene have been identified as causing HP. The R122H (previously known as R117H) mutation is the commonest and can be detected by a single and rapid polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) based technique using the AflIII enzyme. This test however may give a false negative result in the presence of a neutral polymorphism within the enzyme recognition site. The frequency of this event was examined by sequencing studies in patients with HP and in healthy controls. METHODS: Of 60 families identified by the UK and Ireland consortium of EUROPAC (European Registry for Hereditary Pancreatitis and Familial Pancreatic Cancer), 51 were screened for R122H, N29I, and A16V mutations using standard techniques, and by sequencing of all five exons of cationic trypsinogen. RESULTS: Twelve families had the N29I mutation, one family had A16V and, on standard testing, 15 families had the R122H mutation. An additional family with the R122H mutation was found on direct sequencing. The false negative result was due to a neutral polymorphism C-->T at the third base of the codon, not affecting the amino acid coded for, destroying the AflIII restriction site. This polymorphism was not observed in 50 DNA specimens (100 chromosomes) from controls nor from 50 individuals from PRSS1 mutation negative HP families. A novel mutation specific PCR was developed to avoid this pitfall. CONCLUSIONS: One of the 16 families with HP and an R122H mutation contained a polymorphism affecting the AflIII restriction site. Adoption of an alternative R122H assay is important for genetic studies in individuals with apparent HP.

Acute Disease↗

Assessment of HER2 status in breast cancer: why, when and how?

Human epidermal growth factor receptor 2 (HER2) is overexpressed, usually as a result of HER2 proto-oncogene amplification, in 20-30% of breast cancers. A HER2-positive status is generally associated with more aggressive disease and a worse prognosis. Furthermore, a positive HER2 status may predict the likelihood of resistance to some conventional therapies, as well as probably being predictive of sensitivity to anthracycline dose intensification. In addition to this prognostic/predictive value, HER2 is a target for specific therapy, with anti-HER2 monoclonal antibody therapy available in the USA. This article reviews the different assays used to determine HER2 status, discussing their relative advantages/disadvantages and the need for their standardisation before integration alongside other pathological indices into the clinical management of breast cancer.

Biomarkers, Tumor↗

Elastin: mutational spectrum in supravalvular aortic stenosis.

Supravalvular aortic stenosis (SVAS) is a congenital narrowing of the ascending aorta which can occur sporadically, as an autosomal dominant condition, or as one component of Williams syndrome. SVAS is caused by translocations, gross deletions and point mutations that disrupt the elastin gene (ELN) on 7q11.23. Functional hemizygosity for elastin is known to be the cause of SVAS in patients with gross chromosomal abnormalities involving ELN. However, the pathogenic mechanisms of point mutations are less clear. One hundred patients with diagnosed SVAS and normal karyotypes were screened for mutations in the elastin gene to further elucidate the molecular pathology of the disorder. Mutations associated with the vascular disease were detected in 35 patients, and included nonsense, frameshift, translation initiation and splice site mutations. The four missense mutations identified are the first of this type to be associated with SVAS. Here we describe the spectrum of mutations occurring in familial and sporadic SVAS and attempt to define the mutational mechanisms involved in SVAS. SVAS shows variable penetrance within families but the progressive nature of the disorder in some cases, makes identification of the molecular lesions important for future preventative treatments.

Alternative Splicing↗

Induction of remission after donor leucocyte infusion for the treatment of relapsed chronic idiopathic myelofibrosis following allogeneic transplantation: evidence for a 'graft vs. myelofibrosis' effect.

A 54-year-old man showed evidence of disease progression and a reduction in donor chimaerism by molecular microsatellite analysis 6 months after an allogeneic peripheral blood stem cell transplant for chronic idiopathic myelofibrosis. He was treated with a single infusion of donor leucocyte infusions (DLI), which led to the development of mild acute graft versus host disease (GVHD) and the rapid restoration of full donor haemopoiesis. This subsequently led to a progressive reduction in marrow fibrosis from grade IV to grade I over the following 6 months. We believe that this is the first report to provide clear evidence for the efficacy of DLI in this setting, which also provides evidence for the existence of a T-cell-mediated 'graft vs. myelofibrosis' effect similar to that seen against other haematological malignancies.

Chronic Disease↗

Immunohistochemical detection of steroid receptors in breast cancer: a working protocol. UK Receptor Group, UK NEQAS, The Scottish Breast Cancer Pathology Group, and The Receptor and Biomarker Study Group of the EORTC.

The biochemical assay for the oestrogen receptor has shown the clinical value of knowing the concentration of the receptor within tissue. The immunohistochemical assay is rapidly taking over from the biochemical assay. Therefore, it is vital to have an equivalent scoring system that will have the same predictive value. This paper reports both a practical protocol and a scoring system that should achieve this aim. This approach should be applicable to many more biomarkers detected by immunohistochemistry.

Biomarkers, Tumor↗

AIDS: the development of a gender appropriate research intervention.

This study is part of an AIDS research-service project, implemented by a faculty member and graduate students from the University of Maryland, School of Social Work. It focuses on the last of the completed studies between 1993 and 1998. To access women-centered health care services in Washington, D.C., a four member team engaged in a gender-specific research intervention. Nine women with AIDS were hand picked and interviewed. The research team wanted the women with HIV/AIDS to have a forum in which to tell their stories, in their own words regarding their medical and social service needs. Anecdotal accounts from the researchers' journals provide descriptions for findings. Qualitative evaluation theories guided the development of the interview questions. This study explores demographic factors, method of contraction, symptoms, initial reactions, support systems, level of satisfaction and frustration with services, physical health-care needs, social service needs, including legal, housing, financial and mental health needs of women living with HIV/AIDS. The literature search reaffirmed the gender related disparities of services offered found by the team in the field. Recommendations for service providers are given.

Acquired Immunodeficiency Syndrome↗

Allelic imbalance at the LKB1 (STK11) locus in tumours from patients with Peutz-Jeghers' syndrome provides evidence for a hamartoma-(adenoma)-carcinoma sequence.

Patients with Peutz-Jeghers' syndrome (PJS) develop hamartomatous gastrointestinal polyps and characteristic pigmentation, as a result of germline mutations in the LKB1 gene. The hamartomas in PJS were long considered to be without malignant potential. There is, however, accumulating epidemiological evidence to suggest that PJS predisposes to cancers at several different sites (colon, pancreas, breast, ovary, testis, and cervix), although large enough patient samples are rarely available to prove this. Allelic imbalance [allele loss, loss of heterozygosity (LOH)] has previously been reported in a small number of PJS polyps, suggesting that LKB1 acts as a tumour suppressor in these tumours. This study confirms allelic loss at LKB1 in PJS polyps and shows that LOH also occurs in cancers of the colon, breast, and cervix in PJS patients. Allele loss was additionally found in a colonic adenoma from a PJS patient, strongly suggesting the existence of a hamartoma-(adenoma)-carcinoma sequence in tumourigenesis. These results provide molecular evidence that PJS patients are predisposed to cancers at several sites, as a direct result of selection for loss of the 'wild-type' LKB1 allele in tumours. Given the rare involvement of LKB1 in sporadic cancers, these data also suggest that the indirect effect on cancer risk (or 'bystander effect') proposed for hamartomas in juvenile polyposis does not apply to carcinomas in PJS.

AMP-Activated Protein Kinase Kinases↗

Indoor environment, atopy and the risk of the asthma in children in New Zealand.

The objective of this study was to examine the relationship between the indoor environment, atopy and asthma in 7-9-year-old children. Cases and controls were randomly selected from children who participated in the International Study of Asthma and Allergies in Childhood (ISAAC) in Wellington, New Zealand. Cases were children with a previous diagnosis of asthma and current medication use (n = 233) and controls were children with no history of wheezing and no diagnosis of asthma (n = 241). Information was recorded about the indoor environment during the first year of life and currently. Dust was sampled from floors and beds and Der p 1 and Fel d 1 measured using enzyme-linked immunosorbent assays. Skin-prick tests were performed with eight common allergens. Sensitization to Dermatophagoides farinae (OR = 3.19; 95% CI 1.74-5.84), Dermatophagoides pteronyssinus (OR = 2.06; 95% CI 1.16-3.65) and cat (OR = 3.89; 95% CI 1.06-14.30) were independently associated with current asthma. The use of a sheepskin in the first year of life (OR = 1.91; 95% CI 1.11-3.33) was also independently associated with current asthma but current Der p 1 levels showed no association with current asthma. Exposures in early life may be more important than current exposures in determining asthma at age 7-9 years. Prospective studies are needed in New Zealand to determine the relative importance of early life exposures to Der p 1 and other risk factors for asthma.

Air Pollution, Indoor↗

Motogenic activity of IGD-containing synthetic peptides.

Although the IGD amino acid motif (iso-gly-asp) is a highly conserved feature of the fibronectin type I module, no biological activity has as yet been ascribed to it. We have previously reported that the gelatin-binding domain of fibronectin stimulates the migration of human skin fibroblasts into native, but not denatured, type I collagen substrata. Two IGD-containing type I modules are present within the gelatin-binding domain. The object of this study was to ascertain whether soluble synthetic peptides containing the IGD motif stimulate fibroblast migration. We found that IGD peptides stimulated fibroblast migration in the following order of activity: IGDS (as present in the ninth type I module) > IGDQ (as present in the seventh type I module) > IGD. The scrambled SDGI peptide and the well-characterised RGDS peptide were devoid of motogenic activity. The migratory response of fibroblasts to IGD-containing peptides consisted of two distinct phases: an initial period of peptide-mediated cell activation and a subsequent period of enhanced migration manifest in the absence of further IGD peptide. Cell activation was substratum-independent (occurring equally well on both native and denatured type I collagen substrata), whilst the manifestation of enhanced migration was persistent and substratum-dependent (being evident only by cells adherent to a native collagen substratum). Our data further indicated that cell activation (1) is elicited by a signal transduction cascade occurring within minutes of cell exposure to IGD-containing peptides, (2) is dependent upon integrin alphavbeta3 functionality, (3) involves the tyrosine phosphorylation of focal adhesion kinase (ppFAK125) and (4) is inhibited by signalling mediated through integrin alpha5beta1. The expression of migration stimulating activity by soluble IGD-containing peptides clearly distinguishes them from their RGD counterparts. This is the first identified biological activity of the highly conserved IGD motif and provides a rational platform for the development of a novel family of therapeutic compounds designed to stimulate cell migration in relevant clinical situations, such as impaired wound healing.

Amino Acid Motifs↗

Germline mutations of the LKB1 (STK11) gene in Peutz-Jeghers patients.

Germline mutations of the LKB1 (STK11) serine/threonine kinase gene (chromosome 19p13.3) cause Peutz-Jeghers syndrome, which is characterised by hamartomas of the gastrointestinal tract and typical pigmentation. Peutz-Jeghers syndrome carries an overall risk of cancer that may be up to 20 times that of the general population. Here, we report the results of a screen for germline LKB1 mutations by DNA sequencing in 12 Peutz-Jeghers patients (three sporadic and nine familial cases). Mutations were found in seven (58%) cases, in exons 1, 2, 4, 6, and 9. Five of these mutations, two of which are identical, are predicted to lead to a truncated protein (three frameshifts, two nonsense changes). A further mutation is an in frame deletion of 6 bp, resulting in a deletion of lysine and asparagine; the second of these amino acids is conserved between species. The seventh mutation is a missense change in exon 2, converting lysine to arginine, affecting non-conserved amino acids and of uncertain functional significance. Despite the fact that Peutz-Jeghers syndrome is usually an early onset disease with characteristic clinical features, predictive and diagnostic testing for LKB1 mutations will be useful for selected patients in both familial and non-familial contexts.

AMP-Activated Protein Kinase Kinases↗