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Biomedical subjects

A Hunter

Publications and source records attributed to A Hunter.

At least 19 recordsLinked to original sources

LegumeDB1 bioinformatics resource: comparative genomic analysis and novel cross-genera marker identification in lupin and pasture legume species.

The identification of markers in legume pasture crops, which can be associated with traits such as protein and lipid production, disease resistance, and reduced pod shattering, is generally accepted as an important strategy for improving the agronomic performance of these crops. It has been demonstrated that many quantitative trait loci (QTLs) identified in one species can be found in other plant species. Detailed legume comparative genomic analyses can characterize the genome organization between model legume species (e.g., Medicago truncatula, Lotus japonicus) and economically important crops such as soybean (Glycine max), pea (Pisum sativum), chickpea (Cicer arietinum), and lupin (Lupinus angustifolius), thereby identifying candidate gene markers that can be used to track QTLs in lupin and pasture legume breeding. LegumeDB is a Web-based bioinformatics resource for legume researchers. LegumeDB analysis of Medicago truncatula expressed sequence tags (ESTs) has identified novel simple sequence repeat (SSR) markers (16 tested), some of which have been putatively linked to symbiosome membrane proteins in root nodules and cell-wall proteins important in plant-pathogen defence mechanisms. These novel markers by preliminary PCR assays have been detected in Medicago truncatula and detected in at least one other legume species, Lotus japonicus, Glycine max, Cicer arietinum, and (or) Lupinus angustifolius (15/16 tested). Ongoing research has validated some of these markers to map them in a range of legume species that can then be used to compile composite genetic and physical maps. In this paper, we outline the features and capabilities of LegumeDB as an interactive application that provides legume genetic and physical comparative maps, and the efficient feature identification and annotation of the vast tracks of model legume sequences for convenient data integration and visualization. LegumeDB has been used to identify potential novel cross-genera polymorphic legume markers that map to agronomic traits, supporting the accelerated identification of molecular genetic factors underpinning important agronomic attributes in lupin.

Chromosome Mapping↗

Comparison of different reference values of fetal blood flow velocity in the middle cerebral artery for predicting fetal anemia.

OBJECTIVES: To compare different normal reference ranges of fetal blood flow velocity in the middle cerebral artery for predicting fetal anemia. METHODS: Eight reference ranges of either middle cerebral artery peak or time-averaged mean velocities were compared using the area under the receiver-operating characteristics (ROC) curve for 113 fetal blood samples from 60 women at risk of fetal red blood cell alloimmunization. RESULTS: The areas under the ROC curves of the different ranges were not significantly different but there were marked differences in sensitivity (range, 7.14-91.78%) and specificity (range, 31.25-96.88%) with the currently used cut-offs. Except for Mari's range, the best theoretical cut-offs, defined as those having the best sensitivity with the best specificity, differed from those in current use, especially when using time-averaged mean velocity. CONCLUSIONS: Any of the previously reported reference ranges perform well in the non-invasive prediction of fetal anemia. However, with the exception of Mari's curve, the currently employed cut-offs for predicting fetal anemia should be changed, some of them markedly, in order to provide reliable support for clinical decisions.

Blood Flow Velocity↗

Prenatal diagnosis of echogenic lung: evolution and outcome.

OBJECTIVES: Despite the feasibility of detecting lung lesions by antenatal ultrasound, there are problems in correlating the prenatal diagnosis with the final histology and in predicting the outcome. In order to better describe these factors, we reviewed the outcome of fetuses that had been diagnosed with echogenic lung in a referral fetal medicine unit. METHODS: We searched the database of a tertiary fetal medicine unit for all cases of fetal echogenic lung seen since 1994 and studied the maternal and neonatal records found. RESULTS: There were 48 cases of echogenic lung diagnosed at a median gestational age of 21 (range, 19-29) weeks, including 43 (90%) cases of congenital cystic adenomatoid malformation (CCAM) and 5 (10%) of pulmonary sequestration (PS). The evolution of the fetal abnormality after diagnosis was: in 22 (45.8%) cases the lesion disappeared; in 17 (35.5%) cases the lesion remained stable and six (12.5%) cases became severe. Three (6%) women underwent termination of pregnancy. The lesions were equally distributed between the two sides of the thorax. Mediastinal shift was associated with a threefold increase in the possibility of clinical deterioration (17% vs. 5%), and the disappearance of the lesion was twice as likely to occur when the lesion was classified as microcystic as when it was macrocystic (67% vs. 36%). Features of hydrops were found in 9 (21%) fetuses and in six (13%) cases progressed and resulted in intrauterine or neonatal death. Sixty-four percent of cases with lesions that disappeared during the pregnancy had an abnormal computed tomography (CT) scan, and the prenatal diagnosis correlated with histology in 36% of these cases. Of the cases in which the lesions remained stable, 70.5% had an abnormal CT scan and the prenatal diagnosis correlated with the histology in 67% of the cases. CONCLUSIONS: Prenatally diagnosed echogenic lung has a good prognosis in the absence of hydrops. The ability to correctly assess echogenic lung lesions and the need for surgery by prenatal ultrasound is limited.

Cystic Adenomatoid Malformation of Lung, Congenita↗

Complete coding sequences of the rabbitpox virus genome.

Rabbitpox virus (RPXV) is highly virulent for rabbits and it has long been suspected to be a close relative of vaccinia virus. To explore these questions, the complete coding region of the rabbitpox virus genome was sequenced to permit comparison with sequenced strains of vaccinia virus and other orthopoxviruses. The genome of RPXV strain Utrecht (RPXV-UTR) is 197 731 nucleotides long, excluding the terminal hairpin structures at each end of the genome. The RPXV-UTR genome has 66.5 % A + T content, 184 putative functional genes and 12 fragmented ORF regions that are intact in other orthopoxviruses. The sequence of the RPXV-UTR genome reveals that two RPXV-UTR genes have orthologues in variola virus (VARV; the causative agent of smallpox), but not in vaccinia virus (VACV) strains. These genes are a zinc RING finger protein gene (RPXV-UTR-008) and an ankyrin repeat family protein gene (RPXV-UTR-180). A third gene, encoding a chemokine-binding protein (RPXV-UTR-001/184), is complete in VARV but functional only in some VACV strains. Examination of the evolutionary relationship between RPXV and other orthopoxviruses was carried out using the central 143 kb DNA sequence conserved among all completely sequenced orthopoxviruses and also the protein sequences of 49 gene products present in all completely sequenced chordopoxviruses. The results of these analyses both confirm that RPXV-UTR is most closely related to VACV and suggest that RPXV has not evolved directly from any of the sequenced VACV strains, since RPXV contains a 719 bp region not previously identified in any VACV.

Base Sequence↗

Analysis of outcome following allogeneic haemopoietic stem cell transplantation for myeloma using myeloablative conditioning--evidence for a superior outcome using melphalan combined with total body irradiation.

We have undertaken a retrospective multicentre analysis of 139 patients (median age 44.4 years) undergoing allogeneic haematopoietic stem cell transplantation (HSCT) for multiple myeloma using myeloablative conditioning. The majority of patients received total body irradiation (TBI) combined with either melphalan (56.9%) or cyclophosphamide (28.5%). Overall, transplant-related mortality (TRM) was 37.9% at 1 year and was not significantly different for patients receiving melphalan/TBI compared with cyclophosphamide/TBI. The overall complete remission (CR) rate, including patients in CR at the time of transplant, was greater for patients receiving melphalan/TBI (64.7%) compared with cyclophosphamide/TBI (47.2%)(P = 0.085). A significantly higher proportion of patients with continuing disease at the time of transplant achieved CR post-transplant following melphalan/TBI conditioning compared with cyclophosphamide/TBI (52.9% and 33.4% respectively, P = 0.009). Relapse/progression rates at 5 years were significantly lower for melphalan/TBI (36.7%) compared with cyclophosphamide/TBI (80.8%, P < 0.0001) and remained significant in multivariate analysis. This resulted in an overall survival at 5 years of 44.1% and 28.1% for melphalan/TBI and cyclophosphamide/TBI, respectively (P = 0.059). These results demonstrate that the type of conditioning for sibling allogeneic HSCT for myeloma has a major effect on transplant outcome.

Adult↗

Psychological and genetic counseling implications for adolescent daughters of mothers with breast cancer.

Adolescent daughters of women with breast cancer (BC) are themselves at risk for heritable BC. Although some preliminary evidence suggests this group is at an increased risk for emotional problems, evidence is limited to studies with small samples and no comparison groups. This study examined psychological and family functioning, health attitudes and beliefs about genetic risks in adolescent females. A case-comparison design was used to compare 55 mother-daughter pairs in which the mother had been treated for BC (BC group) to 55 families from the general population (GP). Participants completed an assessment battery measuring perceptions of personal risk for BC and attitudes about gene testing for BC susceptibility, family functioning, and adolescent psychological adjustment. Based on manova, no significant differences were found between the two groups on measures of the psychological functioning. However, BC group adolescents reported significant (p < 0.01) worries about their future health and genetic risk for BC. About 68% of BC adolescents compared with 12% of GP adolescents reported being moderately to greatly concerned about their susceptibility to genetic mutations. Further, 85% of BC group adolescents believed they were susceptible to BC compared with 10% of GP adolescents. The results indicated no evidence of emotional, behavioral, or familial distress in these families. However, BC adolescents have significant worries about their future health. The results of this study demonstrate the need to develop a comprehensive model of care where accurate information about genetics and health risks can be provided. The adolescents also need support to help them cope and communicate with their mothers their worries about BC.

Adolescent↗

Maternal anxiety and fetal behavior at 15 weeks' gestation.

OBJECTIVE: To analyze the relationship between maternal anxiety and fetal behavior at 15 weeks' gestation. METHODS: Twenty women in two groups were studied: 10 women underwent amniocentesis and 10 controls did not. Maternal anxiety was evaluated using the State Trait Anxiety Inventory questionnaire. Maternal plasma catecholamines (noradrenaline, adrenaline, dopamine) and maternal serum adrenocorticotropic hormone, cortisol, glucose, insulin, triiodothyronine, thyroxine and thyroid-stimulating hormone were measured. Catecholamines were also measured in the amniotic fluid of women undergoing amniocentesis. Compiled actograms of 40-min observations were done using ultrasonography. RESULTS: Maternal state-anxiety was significantly increased in the amniocentesis group. Except for fetal hiccups (r = 0.49, P = 0.03) there was no significant correlation between maternal anxiety and any of the other studied fetal movements. Maternal glucose was significantly correlated with hiccups (r = -0.59, P = 0.01), isolated leg movements (r = -0.52, P = 0.03), startles (r = -0.47, P = 0.04) and the total of the studied movements (r = -0.47, P = 0.04). Amniotic fluid catecholamines were significantly correlated with hand-face contact (r = 0.71, P = 0.02 for adrenaline), startles (r = 0.75, P = 0.01 for noradrenaline and r = 0.64, P = 0.04 for dopamine) and general movements (r = 0.89, P = 0.001 for noradrenaline). CONCLUSIONS: This study does not support a relationship between maternal anxiety and fetal behavior in early pregnancy. Maternal glucose and plasma catecholamines could be related to fetal movements at 15 weeks' gestation.

Adult↗

Predictive, pre-natal and diagnostic genetic testing for Huntington's disease: the experience in Canada from 1987 to 2000.

Predictive and pre-natal testing for Huntington's Disease (HD) has been available since 1987. Initially this was offered by linkage analysis, which was surpassed by the advent of the direct mutation test for HD in 1993. Direct mutation analysis provided an accurate test that not only enhanced predictive and pre-natal testing, but also permitted the diagnostic testing of symptomatic individuals. The objective of this study was to investigate the uptake, utilization, and outcome of predictive, pre-natal and diagnostic testing in Canada from 1987 to April 1, 2000. A retrospective design was used; all Canadian medical genetics centres and their affiliated laboratories offering genetic testing for HD were invited to participate. A total of 15 of 22 centres (68.2%), currently offering or ever having offered genetic testing for HD, responded, providing data on test results, demographics, and clinical history. A total of 1061 predictive tests, 15 pre-natal tests, and 626 diagnostic tests were performed. The uptake for predictive testing was approximately 18% of the estimated at-risk Canadian population, ranging from 12.5% in the Maritimes to 20.7% in British Columbia. There appears to have been a decline in the rate of testing in recent years. Of the predictive tests, 45.0% of individuals were found to have an increased risk, and a preponderance of females (60.2%) sought testing. A greater proportion of those at < or = 25% risk sought predictive testing once direct CAG mutation analysis had become available (10.9% after mutation analysis vs 4.7% before mutation analysis, p = 0.0077). Very few pre-natal tests were requested. Of the 15 pre-natal tests, 12 had an increased risk, resulting in termination of pregnancy in all but one. Diagnostic testing identified 68.5% of individuals to be positive by mutation analysis, while 31.5% of those with HD-like symptoms were not found to have the HD mutation. The positive diagnostic tests included 24.5% of individuals with no known prior family history of HD.

Adolescent↗

The outcome of unrelated donor stem cell transplantation for patients with multiple myeloma.

We performed a retrospective analysis of outcome in 45 patients with multiple myeloma receiving unrelated donor stem cell transplants (UD-SCT) in the UK between 1993 and 2002; 17 received myeloablative conditioning regimens and 28 received reduced intensity conditioning (RIC) protocols. Forty patients received pretransplant CAMPATH serotherapy. Forty-two of 45 patients had detectable disease at transplant, but 33 of 45 were chemoresponsive. Sixty per cent of patients had received a previous autograft. Myeloid engraftment was seen in 95% of recipients and was significantly faster in recipients receiving peripheral blood stem cells (P = 0.07) and RIC (P = 0.001). The incidence of severe (grade 3/4) acute graft versus host disease (aGvHD) was 5% (2/40). The 100-d non-relapse mortality was 18% (5/38) following RIC and 53% (9/17) following myeloablative regimens. Twenty-nine per cent of patients achieved a complete remission, 61% a partial remission, giving a 90% overall response rate. At median follow-up (513 d), overall survival was 40%: 54% in the RIC group (median follow-up: 489 d) and 18% in the myeloablative group (median follow-up: 560 d). In recipients of UD-SCT, RIC protocols that incorporated CAMPATH were associated with faster myeloid engraftment, less severe aGvHD and lower 100-d non-relapse mortality than myeloablative regimens, without a corresponding rise in relapse rate during the period of observation.

Adult↗

Measuring women's preferences for breast cancer treatments and BRCA1/BRCA2 testing.

In establishing decision models in the treatment and prevention of breast cancer, it is important to evaluate patients' preferences for such interventions. The objectives of the present study were: (i) to characterize women's preferences for breast cancer treatments and BRCA1/BRCA2 testing, using the rating scale and standard gamble techniques; and (ii) to identify factors associated with these quality of life indices. Data were collected from women with breast cancer (n = 60), high-risk relatives of women with breast cancer (n = 58), and women in the general population (n = 51). Regardless of group membership, participants favoured treatment and prevention options that involved minimal physical invasiveness. Women with breast cancer rated lumpectomy and radiation treatment more highly than high-risk relatives and women in the general population. Preferences did not differ according to participants' intentions to undergo BRCA testing. Age was the only demographic variable associated with health state preferences. These findings hold implications for the application of patient preferences to clinical decision making.

Attitude↗

Proteasome inhibitor-induced apoptosis of B-chronic lymphocytic leukaemia cells involves cytochrome c release and caspase activation, accompanied by formation of an approximately 700 kDa Apaf-1 containing apoptosome complex.

Proteasome inhibitors, including lactacystin and MG132 (carbobenzoxyl-leucinyl-leucinyl-leucinal), potently induce apoptosis in leukaemic B cells from patients with B cell chronic lymphocytic leukaemia (B-CLL). This pro-apoptotic effect occurs in cells from patients at all stages of the disease, including those resistant to conventional chemotherapy, suggesting that proteasome inhibitors may be useful for treatment of B-CLL. Following initial inhibition of proteasomal activity, these agents induce mitochondrial cytochrome c release and caspase-dependent apoptosis, involving cleavage/activation of caspases -2, -3, -7, -8 and -9. Pre-treatment with the cell permeable caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp (OMe)fluoromethyl ketone (Z-VAD.fmk), did not prevent the release of cytochrome c or partial processing of caspase-9 but prevented activation of effector caspases and the induction of apoptosis. These results suggest that the release of cytochrome c is caspase independent and that caspase-9 is the initiator caspase in proteasome inhibitor-induced apoptosis of B-CLL cells. Activation of B-CLL lysates with dATP results in the formation of an approximately 700 kDa caspase-activating apoptosome complex containing Apaf-1. We describe for the first time the formation of a similar approximately 700 kDa caspase-activating apoptosome complex in B-CLL cells induced to undergo apoptosis by proteasome inhibitors.

Acetylcysteine↗