Inadvertent anticoagulation of a haemophiliac child with routine line flushing

We report the case of a 3-year-old boy with severe haemophilia A presenting with recurrent haemarthroses despite daily infusions of factor VIII delivered through a central venous access device (CVAD). Regular rinsing of the CVAD with heparin, according to a standard protocol, resulted in systemic anticoagulation, as demonstrated by prolonged thrombin time and therapeutic anti-Xa levels. The bleeding symptoms resolved after replacing heparin with a normal saline solution. This case illustrates that heparin administered to maintain CVAD patency should be used with caution in young haemophiliacs. Prolonged thrombin time should alert the physician to this possible CVAD complication.

Malformations veineuses et coagulopathie

Activation of the coagulation process is frequently encountered in patients with venous vascular malformations and results in the local formation of clots and the consumption of components of the coagulation process (platelets, clotting factors). This activation accounts for multiple biological abnormalities such as the elevation of the D-dimers, reduction of fibrinogen and platelets count and less frequently a local intravascular coagulation (LIC). This process seems to be responsible for the local painful symptoms. In case of LIC, bleeding complications may be observed. Therapeutically, antithrombotic treatment with low-molecular weight heparin can improve the local coagulopathy with beneficial effects on blood tests disturbances, pain and bleeding tendency.

Antiviral efficacy and resistance in patients on antiretroviral therapy in Kigali, Rwanda: the real-life situation in 2002

Our study aimed to complete the published data on ARV therapy in Africa by describing the baseline situation in Rwanda before the launch of a large ARV programme (ESTHER). Prescription habits, frequency and reasons for treatment interruptions but also antiviral efficay, resistance to ARVs and genotypic variability of the viruses present in Rwanda were analysed. Among the 233 patients included in the study, it appeared that a vast majority (91%) were under triple therapy and that half of them had experienced at least one treatment interruption caused mainly by drug shortage or financial difficulties. Among 60 blood samples analysed, 26 were in virological failure with a viral load above 1000 RNA copies/ml and 11 presented major drug resistance mutations. Finally, virological failure could mainly be explained by the high frequency of treatment interruptions but also by the emergence of drug resistance mutations. Consequently the major objective for the ESTHER programme to improve the situation in Rwanda will be to reduce the drug shortage and facilitate the financial accessibility of the treatments.

“SLANG”—Sensitive Language and the New Genetics—an Exploratory Study

SLANG-Sensitive Language and the New Genetics--is a concept that arose out of informal discussions between a number of interested parties, both consumers and professionals, who were becoming increasingly uneasy with some of the language commonly used in medical genetics. Some language choices were felt by the authors to be inappropriate for a variety of reasons. Poor language choice may impede an individual's understanding of a genetic condition or important medical information and the chosen words themselves may simply be perceived as discriminatory and even offensive. SLANG is an important concept to explore partly because literature in this area confirms that language choices in medical settings can be of great significance to both patients and families. Studies have shown how language choices impact on professional practice by, as one example, changing the intended meaning of medical information and affecting individual perception of risk and choice which, in turn, may affect individual or familial well-being. In addition language choice has the power to affect how individuals perceive themselves and are viewed by others. This paper presents the results from our pilot study and discusses the implications for health professionals with particular reference to medical genetics settings.

Microsatellite profile in hormonal receptor genes associated with breast cancer

Given that breast cancer is depending on multiple hormonal influences, the nuclear receptors, estrogen receptor alpha, estrogen receptor beta and androgen receptor, are candidates for cancer susceptibility markers. We conducted an association study in a case-control population (139 cases and 145 controls) by genotyping three potentially functional microsatellites (TA)n, (CA)n and (CAG)n in the ERa, ERb and AR genes respectively. For (CAG)n polymorphism, a significant difference was observed using a cut-off 15 repeats CAG between genotypes short-short/short-long/long-long in cases and control subjects (p = 0.009) and also between the distribution of short/long allele in the two groups of individuals (p = 0.001). Genotypes comprising one or two short (CAG)n sequences had higher risk of breast cancer compared to genotypes with two long allele (odds ratio = 1,93; confidence interval = 1.05-3.55; p = 0.03). No significant difference was observed in allele frequency or in short/long allele percentage for (CA)n or (TA)n polymorphism (cut-off 22 CA and 19 TA repeats), neither in genotype frequencies (short-short, short-long or long-long). When the three microsatellite genotype were taken in analysis, the profile short CA-long TA-short CAG could clearly discriminate between cases and controls (p = 0.006). Also, this combined genotype profile has greater predictive values for breast cancer than (CAG)n genotype alone (predictive positive value 57,1% versus 53,7% and predictive negative value 53% versus 23% respectively). Our results sustain a polygenic model of breast cancer with gene-gene interactions; combined effects of three low-risk polymorphisms conferred significant genetic predisposition. Genotyping hormonal receptor genes ERa, ERb and AR could be a useful genetic marker for defining disease risk.

Role of the mitochondrial DNA 16184-16193 poly-C tract in type 2 diabetes

Recent evidence suggests that polymorphic genetic variation in the non-coding region of mitochondrial DNA (the 16184-16193 polycytosine [poly-C] tract) contributes to the cause of type 2 diabetes, but previous studies only just reached significance. We aimed to investigate this association. We compared patients with type 2 diabetes (n=992) with two independent control groups (n=536, n=1029) from the UK, and saw no difference in the frequency of the 16184-16193 poly-C tract. This finding was confirmed by a meta-analysis of European studies of 1455 patients and 3132 controls (odds ratio 1.16, 95% CI 0.94-1.44). Genetic variation of the 16184-16193 poly-C tract is unlikely to have a major role in the cause of type 2 diabetes.

S100A1 and KIT gene expressions in common subtypes of renal tumours

AIM

The aim of this study is to evaluate the S100A1 and KIT as gene markers for the differentiation of common subtypes of renal tumours.

METHODS

Fifty-five tissue samples (15 clear cell RCCs, 15 papillary RCCs, 7 chromophobe RCCs, 8 oncocytomas and 10 normal renal tissues) were studied The gene expressions of S100A1 and KIT were analysed by one-step RT-PCR by using the specific primers.

RESULTS

S100A1 was expressed in 2/15 clear cell RCCs, 11/15 papillary RCCs, 7/8 oncocytomas and in 0/7 chromophobe RCCs. KIT gene was expressed in 6/7 chromophobe RCCs and 7/8 oncocytomas while 0/15 clear cell RCCs and 1/15 papillary RCCs expressed kit gene. Normal tissue expressed neither S100A1 nor KIT gene.

CONCLUSION

S100A1 and KIT can be used as gene markers for the differentiation of common subtypes of renal tumours.

Increased expression of receptor activator of NF-kappaB ligand (RANKL), its receptor RANK and its decoy receptor osteoprotegerin in the colon of Crohn's disease patients

Crohn's disease (CD) is associated with low bone mass due to chronic inflammation and other factors. Receptor activator of NF-kappaB ligand (RANKL), its receptor RANK and its decoy receptor osteoprotegerin (OPG) are potentially involved in this process as they regulate osteoclastogenesis and are influenced by pro-inflammatory cytokines. The aim of this study was to determine the levels of soluble RANKL (sRANKL), RANK and OPG expression both in the serum and in the colon of CD patients. Levels of sRANKL and OPG were assessed in the serum and the supernatants of cultured colonic biopsies in patients with CD and controls by ELISA. RANK expression was explored by immunostaining and immunofluorescence of fixed colonic samples. OPG and sRANKL levels were higher in the serum of CD patients as compared to age- and sex-matched controls. Levels of sRANKL and OPG were significantly enhanced in cultured colonic biopsies from CD, and OPG levels correlated with histological inflammation, and pro- and anti-inflammatory cytokine levels. No significant correlation was found for sRANKL. RANK+ cells were increased in the colon of CD, particularly in inflamed areas. These cells were positive for CD68 or S100 protein. We conclude that serum and local levels of sRANKL and OPG are increased in CD. Moreover, RANK is expressed in the colonic mucosa by subpopulations of activated macrophages or dendritic cells at higher levels in CD compared to normal colon.

Diverse effects of Ace inhibitors and angiotensin II receptor antagonists on prevention of cardiac hypertrophy and collagen distribution in spontaneously hypertensive rats

This study has compared the effects of two structurally different angiotensin converting enzyme inhibitors (ACEis) such as zofenopril (Zof, with sulfhydrylic group) and lisinopril (Lis, with carboxylic group) and an angiotensin II AT(1) receptor antagonist (losartan, Los) on the prevention of cardiac hypertrophy and collagen distribution in spontaneously hypertensive rats (SHRs). The SHRs were untreated or received: Zof (10 mg/kg/day), Lis (10 mg/kg/day) or Los (20 mg/kg/day) in drinking water starting at 4 weeks of age. At 8, 16 and 24 weeks of age, 8 rats/group were sacrificed for determination of blood pressure, cardiac hypertrophy and collagen distribution. All treatments significantly decreased blood pressure and cardiac indices, expressed as the ventricles to body weight ratio, both variables being significantly correlated. Total ventricular collagen content was similarly decreased in all treated groups. Zof significantly increased the expression of collagen type III and normalized the collagen type I/III ratio. These results suggest that the effects of these drugs on different types of collagen are independent from angiotensin II formation. Similar findings obtained with captopril seem to indicate that the antioxidant sulfhydrylic group of these ACEis can play a role in the distribution of collagen during cardiac hypertrophy.

Cardiovascular effects of treatment of type 2 diabetes with pioglitazone, metformin and gliclazide

Cardiovascular mortality and morbidity are increased in patients with type 2 diabetes. However, there are few data from clinical trials comparing cardiovascular effects of alternative oral anti-diabetic agents. Major cardiovascular outcomes during four one-year, double-blind trials in over 3700 patients with type 2 diabetes randomised to either a thiazolidinedione, pioglitazone, metformin or a sulphonylurea, gliclazide treatment have been combined. Mean blood pressure was slightly reduced by all treatments, with pioglitazone treatment resulting in the largest falls (approximately 1.5 mmHg). Hospitalisations for cardiac or cerebrovascular events were similar with the different treatments. Overall mortality was seven of 1857 for pioglitazone and 10 of 1856 for non-pioglitazone treatments, of which three and six were cardiac deaths, respectively. The incidence of congestive cardiac failure was similar with pioglitazone (12/1857) and non-pioglitazone (10/1856) treatments. The results show similar cardiovascular outcome for the three different treatments over a one-year period, but demonstrate interesting differences, which will require longer-term formal outcome studies to determine their significance.

Fas-beyond death: a regenerative role for Fas in the nervous system

Fas (CD95, APO-1), a member of the TNF superfamily, is a prototypical "death receptor" which transduces apoptotic signals in a variety of cell types. However, cell death is not the only possible outcome of Fas signalling. Fas engagement by Fas Ligand can also trigger proliferation or differentiation, promote tumour progression and angiogenesis, and induce cytokine secretion and integrin expression. Recently, we have reported that Fas engagement induces a potent regenerative response in sensory neurons in vitro, and enhances peripheral nerve regeneration in vivo. In contrast, other types of neurons, notably motoneurons, are acutely sensitive to Fas-induced apoptosis. Here, we review the literature on non-apoptotic Fas signalling pathways, and discuss the potential roles, molecular mechanisms, and regulators of Fas signalling in the nervous system.

High incidence of complications after 2-chloro-2'-deoxyadenosine combined with cyclophosphamide in patients with advanced lymphoproliferative malignancies

The combination of purine analogs with alkylating agents is able to produce a synergistic antitumoral effect. However, the addition of immunosuppressive and DNA-targeting agents might increase purine analog-related complications. The risk for serious complications was evaluated in 38 patients treated with 2-chloro-2'-deoxyadenosine (CDA) and cyclophosphamide (CP). The diagnoses were chronic lymphocytic leukemia (CLL) in 15, Waldenström's macroglobulinemia in 4, mantle cell lymphoma in 6, follicular non-Hodgkin's lymphoma (NHL) in 10, and other low-grade NHL in 3 patients. All patients were pretreated (median: 2 lines, range: 1-5) and 23 (61%) were refractory. The patients received a median of two courses (range: 1-5) of 5.6 mg/m(2) CDA, followed by a median of 200 mg/m(2) CP, for 3 days. The response rate was 51% [complete remission (CR): 14%, partial remission (PR): 38%]. Grade 3/4 infections occurred in 16 (42%) patients. Dose-limiting cytopenias were seen in 22 (58%) patients. In 12 (32%) patients, autoimmune manifestations developed requiring treatment in most of them. Second cancers arose in five (13%) patients (myelodysplastic syndrome/acute myelocytic leukemia in three, lung cancer in two). Multivariate analysis showed that cytopenias, gender (F), prior radiotherapy, and age (>65 years) predicted for the complications seen after CDA-CP. To conclude, because of the high incidence of complications, caution is warranted in selecting patients with advanced lymphoid malignancies for the CDA-CP protocol.

Simple DNA extraction method for dried blood spots and comparison of two PCR assays for diagnosis of vertical human immunodeficiency virus type 1 transmission in Rwanda

Dried blood spots (DBS) on filter paper facilitate the collection, transport, and storage of blood samples for laboratory use. A rapid and simple DNA extraction procedure from DBS was developed and evaluated for the diagnosis of human immunodeficiency virus type 1 (HIV-1) infection in children by an in-house nested-PCR assay on three genome regions and by the Amplicor HIV-1 DNA prototype assay version 1.5 (Roche Molecular Systems). A total of 150 samples from children born to HIV-1-infected mothers were collected in Kigali, Rwanda, in parallel as DBS and as peripheral blood mononuclear cell (PBMC) pellets. The results obtained on DBS by the two PCR assays were compared to the results of nested PCR on PBMCs. Of 150 PBMC samples, 10 were positive, 117 were negative, and 23 were indeterminate for HIV-1 infection. In DNA extracted from filter papers and amplified by using the in-house nested PCR, 9 of these 10 positive samples (90%) were found to be positive, and 1 was found to be indeterminate (only the pol region could be amplified). All of the negative samples and all of the 23 indeterminate samples tested negative for HIV-1 infection. When we used the Amplicor DNA test on DBS, all of the 10 PBMC-positive samples were found to be positive and all of the 23 indeterminate samples were found to be negative. Of the PBMC-negative samples, 115 were found to be negative and 2 were found to be indeterminate. We conclude that this simple rapid DNA extraction method on DBS in combination with both detection methods gave a reliable molecular diagnosis of HIV-1 infection in children born to HIV-infected mothers.

Results of a collaborative study of the EDNAP group regarding mitochondrial DNA heteroplasmy and segregation in hair shafts

A collaborative exercise was carried out by the European DNA Profiling Group (EDNAP) in order to evaluate the distribution of mitochondrial DNA (mtDNA) heteroplasmy amongst the hairs of an individual who displays point heteroplasmy in blood and buccal cells. A second aim of the exercise was to study reproducibility of mtDNA sequencing of hairs between laboratories using differing chemistries, further to the first mtDNA reproducibility study carried out by the EDNAP group. Laboratories were asked to type 2 sections from each of 10 hairs, such that each hair was typed by at least two laboratories. Ten laboratories participated in the study, and a total of 55 hairs were typed. The results showed that the C/T point heteroplasmy observed in blood and buccal cells at position 16234 segregated differentially between hairs, such that some hairs showed only C, others only T and the remainder, C/T heteroplasmy at varying ratios. Additionally, differential segregation of heteroplasmic variants was confirmed in independent extracts at positions 16093 and the poly(C) tract at 302-309, whilst a complete A-G transition was confirmed at position 16129 in one hair. Heteroplasmy was observed at position 16195 on both strands of a single extract from one hair segment, but was not observed in the extracts from any other segment of the same hair. Similarly, heteroplasmy at position 16304 was observed on both strands of a single extract from one hair. Additional variants at positions 73, 249 and the HVII poly(C) region were reported by one laboratory; as these were not confirmed in independent extracts, the possibility of contamination cannot be excluded. Additionally, the electrophoresis and detection equipment used by this laboratory was different to those of the other laboratories, and the discrepancies at position 249 and the HVII poly(C) region appear to be due to reading errors that may be associated with this technology. The results, and their implications for forensic mtDNA typing, are discussed in the light of the biology of hair formation.

Attenuated signature-tagged mutagenesis mutants of Brucella melitensis identified during the acute phase of infection in mice

For this study, we screened 1,152 signature-tagged mutagenesis mutants of Brucella melitensis 16M in a mouse model of infection and found 36 of them to be attenuated in vivo. Molecular characterization of transposon insertion sites showed that for four mutants, the affected genes were only present in Rhizobiaceae. Another mutant contained a disruption in a gene homologous to mosA, which is involved in rhizopine biosynthesis in some strains of Rhizobium, suggesting that this sugar may be involved in Brucella pathogenicity. A mutant was disrupted in a gene homologous to fliF, a gene potentially coding for the MS ring, a basal component of the flagellar system. Surprisingly, a mutant was affected in the rpoA gene, coding for the essential alpha-subunit of the RNA polymerase. This disruption leaves a partially functional protein, impaired for the activation of virB transcription, as demonstrated by the absence of induction of the virB promoter in the Tn5::rpoA background. The results presented here highlight the fact that the ability of Brucella to induce pathogenesis shares similarities with the molecular mechanisms used by both Rhizobium and Agrobacterium to colonize their hosts.

The impact of galactosaemia on quality of life--a pilot study

Galactosaemia (galactose-1-phosphate uridyltransferase deficiency) is a pan-ethnic autosomal recessive disorder of galactose metabolism, with an estimated prevalence of 1 in 40-50000. In this pilot study, we aimed to examine the impact of galactosaemia on patients' everyday emotions, schooling, work, friendships, communication, physical activities, self-esteem and body image. We interviewed all patients with galactosaemia who attended our clinic over 2002-2003, aged 6 years and above (n = 13, age range 6-23 years) and, when possible, their parents (n = 12). The questionnaire used was based on an adaptation of the Minneapolis-Manchester QOL survey and the Australian Child Health Questionnaire. Interpersonal problems, bullying and having a hard time getting along with others, excessive anger on a regular basis, sleeping problems and problems with academic achievement, particularly with mathematics, were common. Significant differences were found between patients' and parents' perceptions, with 7/13 patients nominating the dietary restrictions and 4/7 parents nominating long-term issues as the most distressing aspect of having galactosaemia. In addition, most patients felt they were treated differently from their siblings by their parents, yet all parents felt they treated their child with galactosaemia as their other children. We conclude that galactosaemia has a significant impact on the psychosocial aspects of patients' lives. Clinicians should be aware that parents and patients can have different perspectives of the impact of galactosaemia on quality of life.

Salinity effects on immune parameters of Ruditapes philippinarum challenged with Vibrio tapetis

The occurrence of brown ring disease (BRD) in farmed Manila clams Ruditapes philippinarum is seasonal. Development of the disease is believed to require the presence of the infective agent Vibrio tapetis and particular environmental conditions. This paper studies the effect of salinity (20 to 40 per thousand) on measurable immune parameters of Manila clams, and the progression of BRD in experimentally infected individuals. At 20 per thousand salinity, the total haemocyte count was reduced and disease prevalence was highest. At 40 per thousand salinity significantly fewer clams presented signs of BRD, and this was correlated with increases in the total haemocyte count, hyalinocyte count, phenoloxidase levels and phagocytic activity of haemocytes. Inoculation of clams with V. tapetis did not have a significant effect on the immune parameters measured. Thus, this laboratory-based study relates environmental stress to disease development.