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1.
BMJ Case Rep ; 13(10)2020 Oct 27.
Article in English | MEDLINE | ID: mdl-33109695

ABSTRACT

Pituitary metastases, especially from a primary hepatocellular carcinoma (HCC), are rare. Review of the literature revealed only few cases reporting pituitary metastases complicated by panhypopituitarism from HCC. Calvarial metastases from HCC are even more rare. Here, we present a unique case of primary HCC with metastases to both the calvarium and the pituitary causing panhypopituitarism and bilateral ophthalmoplegia, respectively. To our knowledge, this is the first reported case of two unique and rare complications from metastatic HCC.


Subject(s)
Carcinoma, Hepatocellular/secondary , Hypopituitarism/etiology , Liver Neoplasms/diagnosis , Ophthalmoplegia/etiology , Pituitary Neoplasms/secondary , Rare Diseases , Vascular Neoplasms/secondary , Aged , Carcinoma, Hepatocellular/complications , Carcinoma, Hepatocellular/diagnosis , Cavernous Sinus , Humans , Hypopituitarism/diagnosis , Liver Neoplasms/complications , Magnetic Resonance Imaging , Male , Ophthalmoplegia/diagnosis , Pituitary Gland , Pituitary Neoplasms/diagnosis , Tomography, X-Ray Computed , Vascular Neoplasms/complications , Vascular Neoplasms/diagnosis
3.
Hum Mutat ; 41(1): 277-290, 2020 01.
Article in English | MEDLINE | ID: mdl-31562665

ABSTRACT

The heterogeneous manifestations of MYH9-related disorder (MYH9-RD), characterized by macrothrombocytopenia, Döhle-like inclusion bodies in leukocytes, bleeding of variable severity with, in some cases, ear, eye, kidney, and liver involvement, make the diagnosis for these patients still challenging in clinical practice. We collected phenotypic data and analyzed the genetic variants in more than 3,000 patients with a bleeding or platelet disorder. Patients were enrolled in the BRIDGE-BPD and ThromboGenomics Projects and their samples processed by high throughput sequencing (HTS). We identified 50 patients with a rare variant in MYH9. All patients had macrothrombocytes and all except two had thrombocytopenia. Some degree of bleeding diathesis was reported in 41 of the 50 patients. Eleven patients presented hearing impairment, three renal failure and two elevated liver enzymes. Among the 28 rare variants identified in MYH9, 12 were novel. HTS was instrumental in diagnosing 23 patients (46%). Our results confirm the clinical heterogeneity of MYH9-RD and show that, in the presence of an unclassified platelet disorder with macrothrombocytes, MYH9-RD should always be considered. A HTS-based strategy is a reliable method to reach a conclusive diagnosis of MYH9-RD in clinical practice.


Subject(s)
Genetic Association Studies , Genetic Predisposition to Disease , Genetic Variation , High-Throughput Nucleotide Sequencing , Myosin Heavy Chains/genetics , Adolescent , Adult , Aged , Alleles , Child , Child, Preschool , Chromosome Mapping , Evolution, Molecular , Female , Fluorescent Antibody Technique , Gene Expression , Genetic Association Studies/methods , Genotype , High-Throughput Nucleotide Sequencing/methods , Humans , Infant , Male , Middle Aged , Mutation , Myosin Heavy Chains/metabolism , Phenotype , Young Adult
4.
J Thromb Haemost ; 17(4): 567-573, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30667575

ABSTRACT

Over the past several years, novel modified clotting factor concentrates (CFCs) have been introduced into practice and are now widely prescribed in the countries where they are licensed. These products allow for less frequent infusions of CFC, thereby providing improved convenience and/or higher trough levels. They have been extensively studied for prophylaxis, episodic treatment of bleeding and for surgical prophylaxis. One issue that has emerged regarding the clinical application of these products revolves around the measurement of infused CFC in the clinical coagulation laboratory. Recent studies have demonstrated significant problems with the measurement of correct FVIII/IX levels following infusion of novel CF VIII/IX concentrates. The source of this problem appears to be related to the tremendous variability of the APTT reagents that are used in the one-stage clotting assay, the most commonly used assay for determining factor levels. More specifically, the issue is related to the type of activator used in the reagents. Depending on the combination of the CFC and the APTT activator, the observed results may be either under- or overestimated to degrees that would be clinically relevant. Recommendations based on a review of published information regarding the potential for incorrect measurements of factor VIII/IX levels following infusion of recently developed, novel factor VIII/IX CFCs are presented for the clinician to use in clinical practice.


Subject(s)
Blood Coagulation Factors/pharmacokinetics , Clinical Laboratory Techniques/standards , Coagulants/pharmacokinetics , Drug Monitoring/standards , Partial Thromboplastin Time/standards , Benchmarking , Blood Coagulation Factors/administration & dosage , Blood Coagulation Factors/adverse effects , Coagulants/administration & dosage , Coagulants/adverse effects , Factor IX/pharmacokinetics , Factor VIII/pharmacokinetics , Half-Life , Humans , Predictive Value of Tests , Recombinant Proteins/pharmacokinetics , Reproducibility of Results
5.
Blood ; 129(4): 520-524, 2017 01 26.
Article in English | MEDLINE | ID: mdl-28064200

ABSTRACT

The von Willebrand receptor complex, which is composed of the glycoproteins Ibα, Ibß, GPV, and GPIX, plays an essential role in the earliest steps in hemostasis. During the last 4 decades, it has become apparent that loss of function of any 1 of 3 of the genes encoding these glycoproteins (namely, GP1BA, GP1BB, and GP9) leads to autosomal recessive macrothrombocytopenia complicated by bleeding. A small number of variants in GP1BA have been reported to cause a milder and dominant form of macrothrombocytopenia, but only 2 tentative reports exist of such a variant in GP1BB By analyzing data from a collection of more than 1000 genome-sequenced patients with a rare bleeding and/or platelet disorder, we have identified a significant association between rare monoallelic variants in GP1BB and macrothrombocytopenia. To strengthen our findings, we sought further cases in 2 additional collections in the United Kingdom and Japan. Across 18 families exhibiting phenotypes consistent with autosomal dominant inheritance of macrothrombocytopenia, we report on 27 affected cases carrying 1 of 9 rare variants in GP1BB.


Subject(s)
Blood Platelets/metabolism , Hemorrhage/genetics , Mutation , Platelet Glycoprotein GPIb-IX Complex/genetics , Thrombocytopenia/genetics , Alleles , Blood Platelets/pathology , Case-Control Studies , Female , Gene Expression , Genes, Dominant , Genome, Human , Hemorrhage/diagnosis , Hemorrhage/metabolism , Hemorrhage/pathology , High-Throughput Nucleotide Sequencing , Humans , Male , Pedigree , Platelet Count , Thrombocytopenia/diagnosis , Thrombocytopenia/metabolism , Thrombocytopenia/pathology
6.
Thromb Haemost ; 117(3): 508-518, 2017 02 28.
Article in English | MEDLINE | ID: mdl-28004057

ABSTRACT

The safety, efficacy, and prolonged half-life of recombinant factor IX Fc fusion protein (rFIXFc) were demonstrated in the Phase 3 B-LONG (adults/adolescents ≥12 years) and Kids B-LONG (children <12 years) studies of subjects with haemophilia B (≤2 IU/dl). Here, we report interim, long-term safety and efficacy data from B-YOND, the rFIXFc extension study. Eligible subjects who completed B-LONG or Kids B-LONG could enrol in B-YOND. There were four treatment groups: weekly prophylaxis (20-100 IU/kg every 7 days), individualised prophylaxis (100 IU/kg every 8-16 days), modified prophylaxis (further dosing personalisation to optimise prophylaxis), and episodic (on-demand) treatment. Subjects could change treatment groups at any point. Primary endpoint was inhibitor development. One hundred sixteen subjects enrolled in B-YOND. From the start of the parent studies to the B-YOND interim data cut, median duration of rFIXFc treatment was 39.5 months and 21.9 months among adults/adolescents and children, respectively; 68/93 (73.1 %) adults/adolescents and 9/23 (39.1 %) children had ≥100 cumulative rFIXFc exposure days. No inhibitors were observed. Median annualised bleeding rates (ABRs) were low in all prophylaxis regimens: weekly (≥12 years: 2.3; <6 years: 0.0; 6 to <12 years: 2.7), individualised (≥12 years: 2.3; 6 to <12 years: 2.4), and modified (≥12 years: 2.4). One or two infusions were sufficient to control 97 % (adults/adolescents) and 95 % (children) of bleeding episodes. Interim data from B-YOND are consistent with data from B-LONG and Kids B-LONG, and confirm the long-term safety of rFIXFc, absence of inhibitors, and maintenance of low ABRs with prophylactic dosing every 1 to 2 weeks.


Subject(s)
Coagulants/administration & dosage , Factor IX/administration & dosage , Hemophilia B/drug therapy , Hemorrhage/prevention & control , Hemostasis/drug effects , Immunoglobulin Fc Fragments/administration & dosage , Recombinant Fusion Proteins/administration & dosage , Adolescent , Adult , Antibodies, Neutralizing/blood , Child , Coagulants/adverse effects , Drug Administration Schedule , Factor IX/adverse effects , Factor IX/immunology , Hemophilia B/blood , Hemophilia B/diagnosis , Hemorrhage/blood , Humans , Immunoglobulin Fc Fragments/adverse effects , Immunoglobulin Fc Fragments/immunology , Male , Middle Aged , Recombinant Fusion Proteins/adverse effects , Recombinant Fusion Proteins/immunology , Risk Factors , Time Factors , Treatment Outcome , Young Adult
7.
Sci Transl Med ; 8(328): 328ra30, 2016 Mar 02.
Article in English | MEDLINE | ID: mdl-26936507

ABSTRACT

The Src family kinase (SFK) member SRC is a major target in drug development because it is activated in many human cancers, yet deleterious SRC germline mutations have not been reported. We used genome sequencing and Human Phenotype Ontology patient coding to identify a gain-of-function mutation in SRC causing thrombocytopenia, myelofibrosis, bleeding, and bone pathologies in nine cases. Modeling of the E527K substitution predicts loss of SRC's self-inhibitory capacity, which we confirmed with in vitro studies showing increased SRC kinase activity and enhanced Tyr(419) phosphorylation in COS-7 cells overexpressing E527K SRC. The active form of SRC predominates in patients' platelets, resulting in enhanced overall tyrosine phosphorylation. Patients with myelofibrosis have hypercellular bone marrow with trilineage dysplasia, and their stem cells grown in vitro form more myeloid and megakaryocyte (MK) colonies than control cells. These MKs generate platelets that are dysmorphic, low in number, highly variable in size, and have a paucity of α-granules. Overactive SRC in patient-derived MKs causes a reduction in proplatelet formation, which can be rescued by SRC kinase inhibition. Stem cells transduced with lentiviral E527K SRC form MKs with a similar defect and enhanced tyrosine phosphorylation levels. Patient-derived and E527K-transduced MKs show Y419 SRC-positive stained podosomes that induce altered actin organization. Expression of mutated src in zebrafish recapitulates patients' blood and bone phenotypes. Similar studies of platelets and MKs may reveal the mechanism underlying the severe bleeding frequently observed in cancer patients treated with next-generation SFK inhibitors.


Subject(s)
Bone and Bones/pathology , Hemorrhage/genetics , Mutation/genetics , Primary Myelofibrosis/genetics , Thrombocytopenia/genetics , src-Family Kinases/genetics , Animals , Blood Platelets/pathology , COS Cells , Chlorocebus aethiops , Female , Hematopoiesis , Hemorrhage/complications , Humans , Male , Pedigree , Phenotype , Primary Myelofibrosis/complications , Thrombocytopenia/complications , Transfection , Zebrafish
8.
Blood ; 127(23): 2903-14, 2016 06 09.
Article in English | MEDLINE | ID: mdl-26912466

ABSTRACT

Macrothrombocytopenia (MTP) is a heterogeneous group of disorders characterized by enlarged and reduced numbers of circulating platelets, sometimes resulting in abnormal bleeding. In most MTP, this phenotype arises because of altered regulation of platelet formation from megakaryocytes (MKs). We report the identification of DIAPH1, which encodes the Rho-effector diaphanous-related formin 1 (DIAPH1), as a candidate gene for MTP using exome sequencing, ontological phenotyping, and similarity regression. We describe 2 unrelated pedigrees with MTP and sensorineural hearing loss that segregate with a DIAPH1 R1213* variant predicting partial truncation of the DIAPH1 diaphanous autoregulatory domain. The R1213* variant was linked to reduced proplatelet formation from cultured MKs, cell clustering, and abnormal cortical filamentous actin. Similarly, in platelets, there was increased filamentous actin and stable microtubules, indicating constitutive activation of DIAPH1. Overexpression of DIAPH1 R1213* in cells reproduced the cytoskeletal alterations found in platelets. Our description of a novel disorder of platelet formation and hearing loss extends the repertoire of DIAPH1-related disease and provides new insight into the autoregulation of DIAPH1 activity.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Hearing Loss/genetics , Mutation , Thrombocytopenia/genetics , A549 Cells , Adolescent , Adult , Aged , Case-Control Studies , Cells, Cultured , Child , Female , Formins , Genetic Association Studies , Genetic Predisposition to Disease , HEK293 Cells , Hearing Loss/complications , Humans , Male , Middle Aged , Pedigree , Polymorphism, Single Nucleotide , Syndrome , Thrombocytopenia/complications , Young Adult
9.
Genome Med ; 7(1): 36, 2015.
Article in English | MEDLINE | ID: mdl-25949529

ABSTRACT

BACKGROUND: Heritable bleeding and platelet disorders (BPD) are heterogeneous and frequently have an unknown genetic basis. The BRIDGE-BPD study aims to discover new causal genes for BPD by high throughput sequencing using cluster analyses based on improved and standardised deep, multi-system phenotyping of cases. METHODS: We report a new approach in which the clinical and laboratory characteristics of BPD cases are annotated with adapted Human Phenotype Ontology (HPO) terms. Cluster analyses are then used to characterise groups of cases with similar HPO terms and variants in the same genes. RESULTS: We show that 60% of index cases with heritable BPD enrolled at 10 European or US centres were annotated with HPO terms indicating abnormalities in organ systems other than blood or blood-forming tissues, particularly the nervous system. Cases within pedigrees clustered closely together on the bases of their HPO-coded phenotypes, as did cases sharing several clinically suspected syndromic disorders. Cases subsequently found to harbour variants in ACTN1 also clustered closely, even though diagnosis of this recently described disorder was not possible using only the clinical and laboratory data available to the enrolling clinician. CONCLUSIONS: These findings validate our novel HPO-based phenotype clustering methodology for known BPD, thus providing a new discovery tool for BPD of unknown genetic basis. This approach will also be relevant for other rare diseases with significant genetic heterogeneity.

10.
Platelets ; 26(3): 216-9, 2015.
Article in English | MEDLINE | ID: mdl-24679363

ABSTRACT

Platelet activation is traditionally quantified using turbidimetric aggregometry, which reflects integrin αIIbß3 activity, an important determinant of platelet function during pathophysiological thrombus formation. However, aggregometry does not recreate the shear conditions prevailing during thrombosis in vivo. Here we describe novel whole-frame analysis of real-time video microscopy to quantify platelet adhesion receptor activity under shear in parallel-plate flow chambers. We demonstrate that the rate of change of surface coverage (designated Platelet Population Mobility, PM) quantifies platelet mobility. On collagen, PM falls exponentially to a low level, corresponding to firm platelet adhesion, while on other substrates, PM remains high. Different receptor-specific thrombogenic surfaces reveal that the PM time constant reflects real-time changes in integrins αIIbß3 and α2ß1 activity. This ensemble kinetic analysis has the potential to provide valuable diagnostic information about platelet thrombus formation with both academic and clinical applications.


Subject(s)
Arteries , Blood Platelets/physiology , Platelet Adhesiveness , Platelet Membrane Glycoproteins/metabolism , Shear Strength , Collagen Type I/metabolism , Hemodynamics , Humans , Kinetics , Microscopy, Video , Platelet Activation , Thrombosis/diagnosis , Thrombosis/etiology , Thrombosis/metabolism , von Willebrand Factor/metabolism
11.
Semin Thromb Hemost ; 40(2): 261-8, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24497120

ABSTRACT

Molecular genetic analysis of families with hemophilia and other heritable bleeding disorders is a frequently requested laboratory investigation. In the United Kingdom, laboratories undertaking genetic testing must participate in a recognized external quality assessment scheme for formal accreditation. The UK National External Quality Assessment Scheme (UK NEQAS) for heritable bleeding disorders was established in its current format in 2003, and currently has 27 registered participants in the United Kingdom, the European Union (EU), and the non-EU countries. Two exercises per annum are circulated to participants comprising either whole blood or DNA isolated from cell lines, and laboratories are allowed 6 weeks to analyze the samples and generate a report. Reports are assessed by a panel comprising clinicians and scientists with expertise in this area. Samples to date have involved analysis of the F8 gene (10 exercises), the F9 gene (4 exercises), and the VWF gene (3 exercises) and have comprised a wide spectrum of mutations representing the routine workload encountered in the molecular genetics laboratory. The majority of laboratories in each exercise passed, but a small number did not and reasons for failing included clerical errors, genotyping inaccuracies, and a failure to correctly interpret data. Overall we have seen an improvement in quality of reports submitted for assessment, with a more concise format that will be of value to referring clinicians and counsellors. Informal feedback from participants has been very positive.


Subject(s)
Genetic Testing/standards , Hemorrhagic Disorders/diagnosis , Hemorrhagic Disorders/genetics , Total Quality Management/methods , Cell Line , Clinical Laboratory Techniques/methods , Clinical Laboratory Techniques/standards , DNA Mutational Analysis , Factor IX/genetics , Factor VIII/genetics , Genetic Testing/methods , Genotype , Hemorrhagic Disorders/blood , Humans , Quality Control , Reproducibility of Results , Sensitivity and Specificity , Total Quality Management/trends , United Kingdom , von Willebrand Factor/genetics
12.
Breast Cancer Res Treat ; 138(2): 571-9, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23456194

ABSTRACT

We investigated insulin-like growth factor (IGF)-1 and IGF binding protein (IGFBP)-3 concentrations in histologically normal breast tissues and assessed their association with plasma concentrations, and breast cancer risk factors. IGF-1 and IGFBP-3 were assessed in plasma and breast tissues of 90 women with no history of any cancer and undergoing reduction mammoplasty. Pearson correlations and ANOVAs were used to describe plasma-breast associations and biomarker differences by breast cancer risk factors, respectively. Multivariable regression models were used to determine associations between risk factors, and breast IGF-1 and IGFBP-3. The mean age of the study sample was 37.3 years, 58 % were white, and generally these women were obese (mean BMI = 30.8 kg/m(2)). We observed no plasma-breast correlation for IGF-1, IGFBP-3, or IGF-1/IGFBP-3 (r = -0.08, r = 0.14, and r = 0.03, respectively; p-values >0.05). Through age- and BMI-adjusted analysis, BMI and years of oral contraceptive (OC) use were inversely associated with breast IGF-1 (p-values = 0.02 and 0.003, respectively) and age was associated with breast IGFBP-3 (p = 0.01), while breast IGF-1/IGFBP-3 was higher in blacks than whites (1.08 vs. 0.68, p = 0.04) and associated with age and BMI (p-values = 0.03 and 0.002, respectively). In multivariable-adjusted models, some breast cancer risk factors studied herein explained 24, 10, and 15 % of the variation in breast IGF-1, IGFBP-3, and IGF-1/IGFBP-3, respectively. While reasons for the lack of plasma-breast hormone correlations in these cancer-free women are unknown, several factors were shown to be associated with breast concentrations. The lack of correlation between blood and tissue IGF-1 and IGFBP-3 suggests that studies of breast cancer risk assessing blood IGF-1 and IGFBP-3 may have important limitations in understanding their role in breast carcinogenesis.


Subject(s)
Insulin-Like Growth Factor Binding Protein 3/blood , Insulin-Like Growth Factor I/metabolism , Mammary Glands, Human/metabolism , Adult , Breast Neoplasms/blood , Cross-Sectional Studies , Female , Health , Humans , Linear Models , Mammaplasty , Mammary Glands, Human/surgery , Middle Aged , Multivariate Analysis , Reference Values , Risk Factors
13.
Cancer Epidemiol Biomarkers Prev ; 21(10): 1745-55, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22892282

ABSTRACT

BACKGROUND: Blood adipokines are associated with breast cancer risk; however, blood-breast adipokine correlations and factors that explain variation in adipokines are unknown. METHODS: Plasma (n = 155) and breast (n = 85) leptin and adiponectin were assessed by immunoassays in women with no history of cancer. Multivariable-adjusted regression models were used to determine breast adipokine associations. RESULTS: Through body mass index (BMI)-adjusted analyses, we initially observed positive plasma-breast correlations for leptin (r = 0.41, P = 0.0002) and adiponectin (r = 0.23, P = 0.05). The positive plasma-breast correlation for leptin was strongest among normal weight women (r = 0.62), whereas the correlation for adiponectin was strongest among obese women (r = 0.31). In multivariable models, adjusting for BMI, demographic, reproductive, and lifestyle factors, plasma leptin was not associated with breast leptin, and only the highest quartile of plasma adiponectin was associated with tissue levels. Of the risk factors investigated, those that contributed most to the variation in breast tissue adipokines were BMI and race for leptin, oral contraceptive use and smoking status for adiponectin. CONCLUSIONS: Although we report positive plasma-breast adipokine correlations overall, plasma adipokine concentrations may not be good surrogates for breast concentrations among all women. Predictors of breast adipokines vary, depending on subject characteristics, possibly explaining inconsistent epidemiologic results and they implicate differing pathways toward carcinogenesis. IMPACT: A clearer understanding of the relationships between plasma adipokines and their levels within the target organ is necessary to better understand the impact of these hormones on breast cancer risk. Future studies are needed to identify additional factors associated with breast adipokines in target tissues.


Subject(s)
Adipokines/analysis , Breast Neoplasms/etiology , Breast/chemistry , Adipokines/blood , Adolescent , Adult , Aged , Body Mass Index , Breast Neoplasms/chemistry , Female , Humans , Middle Aged , Regression Analysis , Risk Factors
14.
Eur J Cancer ; 47(18): 2706-14, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22078932

ABSTRACT

PURPOSE: This study assessed the efficacy and safety of linifanib in patients with advanced renal cell carcinoma (RCC) who were previously treated with sunitinib. MATERIALS AND METHODS: This open-label, multicentre, phase 2 trial of oral linifanib 0.25 mg/kg/day enrolled patients who had prior nephrectomy and adequate organ function. The primary end-point was objective response rate (ORR) per response evaluation criteria in solid tumors (RECIST) by central imaging. Secondary end-points were progression-free survival (PFS), overall survival (OS) and time to progression (TTP). Safety was also assessed. RESULTS: Fifty-three patients, median age 61 years (range 40-80) were enrolled (August 2007 to October 2008) across 12 North-American centres. Median number of prior therapies was 2 (range 1-4); 43 patients (81%) had clear-cell histology. ORR was 13.2%, median PFS was 5.4 months (95% Confidence Interval (CI): 3.6, 6.0) and TTP was the same; median OS was 14.5 months (95% CI: 10.8, 24.1). The most common treatment-related adverse events (AEs) were diarrhoea (74%), fatigue (74%) and hypertension (66%), and the most common treatment-related Grade 3/4 AE was hypertension (40%). CONCLUSIONS: Linifanib demonstrated clinically meaningful activity in patients with advanced RCC after sunitinib failure. At 0.25 mg/kg/day, significant dose modifications were required. An alternative, fixed-dosing strategy is being evaluated in other trials.


Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Renal Cell/drug therapy , Indazoles/therapeutic use , Indoles/therapeutic use , Kidney Neoplasms/drug therapy , Phenylurea Compounds/therapeutic use , Pyrroles/therapeutic use , Adult , Aged , Aged, 80 and over , Carcinoma, Renal Cell/mortality , Female , Humans , Indazoles/adverse effects , Indoles/adverse effects , Kidney Neoplasms/mortality , Male , Middle Aged , Phenylurea Compounds/adverse effects , Pyrroles/adverse effects , Sunitinib , Treatment Failure
15.
Biomacromolecules ; 11(11): 3000-6, 2010 Nov 08.
Article in English | MEDLINE | ID: mdl-20954740

ABSTRACT

Orb-weaving spider silk fibers are assembled from very large, highly repetitive proteins. The repeated segments contain, in turn, short, simple, and repetitive amino acid motifs that account for the physical and mechanical properties of the assembled fiber. Of the six orb-weaver silk fibroins, the piriform silk that makes the attachment discs, which lashes the joints of the web and attaches dragline silk to surfaces, has not been previously characterized. Piriform silk protein cDNAs were isolated from phage libraries of three species: A. trifasciata , N. clavipes , and N. cruentata . The deduced amino acid sequences from these genes revealed two new repetitive motifs: an alternating proline motif, where every other amino acid is proline, and a glutamine-rich motif of 6-8 amino acids. Similar to other spider silk proteins, the repeated segments are large (>200 amino acids) and highly homogenized within a species. There is also substantial sequence similarity across the genes from the three species, with particular conservation of the repetitive motifs. Northern blot analysis revealed that the mRNA is larger than 11 kb and is expressed exclusively in the piriform glands of the spider. Phylogenetic analysis of the C-terminal regions of the new proteins with published spidroins robustly shows that the piriform sequences form an ortholog group.


Subject(s)
Short Interspersed Nucleotide Elements/genetics , Silk/genetics , Amino Acid Sequence , Animals , DNA, Complementary/chemistry , DNA, Complementary/genetics , DNA, Complementary/isolation & purification , Molecular Sequence Data , Phylogeny , RNA, Messenger/chemistry , RNA, Messenger/genetics , RNA, Messenger/isolation & purification , Sequence Alignment , Silk/chemistry , Silk/isolation & purification , Species Specificity , Spiders
16.
Br J Haematol ; 150(5): 501-14, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20618331

ABSTRACT

Point-of-care testing (POCT) in haematology has seen a significant increase in both the spectrum of tests available and the number of tests performed annually. POCT is frequently undertaken with the belief that this will reduce the turnaround time for results and so improve patient care. The most obvious example of POCT in haemostasis is the out-of-hospital monitoring of the International Normalized Ratio in patients receiving a vitamin K antagonist, such as warfarin. Other areas include the use of the Activated Clotting Time to monitor anticoagulation for patients on cardio-pulmonary bypass, platelet function testing to identify patients with apparent aspirin or clopidogrel resistance and thrombelastography to guide blood product replacement during cardiac and hepatic surgery. In contrast to laboratory testing, POCT is frequently undertaken by untrained or semi-trained individuals and in many cases is not subject to the same strict quality control programmes that exist in the central laboratory. Although external quality assessment programmes do exist for some POCT assays these are still relatively few. The use of POCT in haematology, particularly in the field of haemostasis, is likely to expand and it is important that systems are in place to ensure that the generated results are accurate and precise.


Subject(s)
Blood Coagulation Tests/methods , Hemostasis , Point-of-Care Systems , Blood Coagulation Tests/standards , Humans , International Normalized Ratio/methods , Platelet Function Tests/methods , Point-of-Care Systems/standards , Quality Assurance, Health Care , Thrombelastography/methods , Whole Blood Coagulation Time/methods
17.
Int J Radiat Oncol Biol Phys ; 76(4): 1140-6, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-19560882

ABSTRACT

PURPOSE: To report the use of high-dose-rate intraoperative radiation therapy (HDR-IORT) for recurrent head-and-neck cancer (HNC) at a single institution. METHODS AND MATERIALS: Between July 1998 and February 2007, 34 patients with recurrent HNC received 38 HDR-IORT treatments using a Harrison-Anderson-Mick applicator with Iridium-192. A single fraction (median, 15 Gy; range, 10-20 Gy) was delivered intraoperatively after surgical resection to the region considered at risk for close or positive margins. In all patients, the target region was previously treated with external beam radiation therapy (median dose, 63 Gy; range, 24-74 Gy). The 1- and 2-year estimates for in-field local progression-free survival (LPFS), locoregional progression-free survival (LRPFS), distant metastases-free survival (DMFS), and overall survival (OS) were calculated. RESULTS: With a median follow-up for surviving patients of 23 months (range, 6-54 months), 8 patients (24%) are alive and without evidence of disease. The 1- and 2-year LPFS rates are 66% and 56%, respectively, with 13 (34%) in-field recurrences. The 1- and 2-year DMFS rates are 81% and 62%, respectively, with 10 patients (29%) developing distant failure. The 1- and 2-year OS rates are 73% and 55%, respectively, with a median time to OS of 24 months. Severe complications included cellulitis (5 patients), fistula or wound complications (3 patients), osteoradionecrosis (1 patient), and radiation-induced trigeminal neuralgia (1 patient). CONCLUSIONS: HDR-IORT has shown encouraging local control outcomes in patients with recurrent HNC with acceptable rates of treatment-related morbidity. Longer follow-up with a larger cohort of patients is needed to fully assess the benefit of this procedure.


Subject(s)
Carcinoma, Squamous Cell/radiotherapy , Head and Neck Neoplasms/radiotherapy , Neoplasm Recurrence, Local/radiotherapy , Adolescent , Adult , Aged , Aged, 80 and over , Carcinoma, Squamous Cell/mortality , Carcinoma, Squamous Cell/secondary , Carcinoma, Squamous Cell/surgery , Child , Disease-Free Survival , Female , Head and Neck Neoplasms/mortality , Head and Neck Neoplasms/surgery , Humans , Intraoperative Period , Iridium Radioisotopes/therapeutic use , Male , Middle Aged , Neoplasm Recurrence, Local/mortality , Neoplasm Recurrence, Local/surgery , Radiotherapy/methods , Radiotherapy Dosage , Young Adult
18.
Ned Tijdschr Geneeskd ; 153: B42, 2009.
Article in Dutch | MEDLINE | ID: mdl-19785809

ABSTRACT

A 69-year-old man of Jewish descent with a second local relapse of rectal carcinoma was found to have a markedly prolonged activated partial thromboplastin time (aPTT). Further evaluation revealed a homozygous factor XI deficiency. Despite various operations in the past he had never displayed any bleeding problems. Severe factor XI deficiency did not prevent venous thrombosis in this patient. The management of patients with prolonged aPTT is described and insight into the pathophysiology of factor XI deficiency is provided. The differential diagnosis in patients with a prolonged aPTT depends on their bleeding tendency. There is a large variability in bleeding tendency in patients with factor XI deficiency. Patients with factor XI deficiency and an increased bleeding tendency can be treated with antifibrinolytic agents prior to small interventions, such as tooth extraction, or with plasma prior to surgery.


Subject(s)
Factor XI Deficiency/diagnosis , Factor XI Deficiency/genetics , Jews/genetics , Partial Thromboplastin Time , Aged , Diagnosis, Differential , Homozygote , Humans , Male
19.
Thromb Haemost ; 102(2): 287-301, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19652879

ABSTRACT

Factor XI (FXI) functions in blood coagulation. FXI is composed of four apple (Ap) domains and a serine protease (SP) domain. Deficiency of FXI leads to an injury-related bleeding disorder, which is remarkable for the lack of correlation between bleeding symptoms and FXI coagulant activity (FXI:C). The number of mutations previously reported in our interactive web database (http://www.FactorXI.org) is now significantly increased to 183 through our new patient studies and from literature surveys. Eight novel missense mutations give a total of 120 throughout the FXI gene (F11). The most abundant defects in FXI are revealed to be those from low-protein plasma levels (Type I: CRM-) that originate from protein misfolding, rather than from functional defects (Type II: CRM+). A total of 70 Ap missense mutations were analysed using a consensus Ap domain structure generated from the FXI dimer crystal structure. This showed that all parts of the Ap domain were affected. The 47 SP missense mutations were also distributed throughout the SP domain structure. The periphery of the Ap beta-sheet structure is sensitive to structural perturbation caused by residue changes throughout the Ap domain, yet this beta-sheet is crucial for FXI dimer formation. Residues located at the Ap4:Ap4 interface in the dimer are much less directly involved. We conclude that the abundance of Type I defects in FXI results from the sensitivity of the Ap domain folding to residue changes within this, and discuss how structural knowledge of the mutations improves our understanding of FXI deficiencies.


Subject(s)
Factor XI Deficiency/genetics , Factor XI/chemistry , Factor XI/genetics , Mutation, Missense , Amino Acid Sequence , Amino Acid Substitution , Base Sequence , Crystallography, X-Ray , DNA/genetics , Databases, Genetic , Dimerization , Factor XI Deficiency/blood , Genes, Dominant , Humans , Models, Molecular , Molecular Sequence Data , Phenotype , Polymorphism, Single Nucleotide , Protein Folding , Protein Structure, Quaternary , Protein Structure, Tertiary , Sequence Homology, Amino Acid
20.
Clin Colorectal Cancer ; 8(3): 163-5, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19632931

ABSTRACT

Reversible posterior leukoencephalopathy (RPLS), also known as posterior reversible encephalopathy syndrome, is characterized by magnetic resonance imaging (MRI) findings of reversible vasogenic subcortical edema without infarction. The clinical presentation is usually nonspecific and typically involves global encephalopathy, seizures, headache, or visual symptoms. MRI of the brain is essential to the diagnosis of RPLS. Typical findings of RPLS include high-intensity signal on T2-weighted images predominantly in the posterior lobes of the brain that is caused by subcortical white matter vasogenic edema. Fluid-attenuated inversion recovery (FLAIR) sequences on MRI improve sensitivity and detect subtle peripheral lesions. This clinical radiographic syndrome has been described in a number of medical conditions, with hypertensive encephalopathy, eclampsia, and the use of immunosuppressant drugs (most notably calcineurin inhibitors) being the most common. It has occasionally been reported with cisplatin and rarely with carboplatin. Its occurrence with oxaliplatin is very unusual. An extensive literature search including PUBMED and direct contact with the drug manufacturer yielded only 2 known case reports. Herein, we describe a case that had classic clinical and radiologic features of RPLS. We also briefly describe 2 other patients who have been described to have RPLS with oxaliplatin in the literature.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/adverse effects , Colonic Neoplasms/drug therapy , Posterior Leukoencephalopathy Syndrome/chemically induced , Fluorouracil/administration & dosage , Humans , Leucovorin/administration & dosage , Magnetic Resonance Imaging , Male , Middle Aged , Organoplatinum Compounds/administration & dosage , Oxaliplatin , Posterior Leukoencephalopathy Syndrome/physiopathology , Prognosis , Treatment Outcome
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