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P Beris

Publications and source records attributed to P Beris.

At least 19 recordsLinked to original sources
PubMed2004

[Erythropoietin and intravenous iron to save blood in surgery].

Recombinant human erythropoietin (rHuEPO) and intravenous (i.v.) iron administration may be useful tools to save blood in surgery. In the perioperative period, rHuEPO should be used in slightly anemic patients for whom an autologous predonation program is not recommended (or feasible). In such cases, i.v. iron is only given if there is a functional or real iron deficiency state. In the post-operative period, i.v. iron is administered in association with rHuEPO in an attempt to rapidly correct severe post-operative anemia. The same regimen is used for patients undergoing surgery for inflammatory bowel disease and rheumatoid arthritis. Finally, other particular categories of patients, such as those with reduced body weight (< 50 kg), candidates for surgery with increased blood needs (> 5 units), or those with a too-short period of time before surgery, also benefit from the administration of these two drugs.

Administration, Oral↗
PubMed2002

Optimized lentiviral transduction of erythroid precursors from healthy adults and patients with myelodysplastic syndromes.

Lentivectors, derived from human immunodeficiency virus-1 (HIV-1), represent a novel investigational and therapeutic tool for targeting hematopoietic progenitor cells. We describe a new protocol whereby we achieved a highly efficient lentiviral transduction of erythroid precursor cells originating from the bone marrow of healthy adults and patients with myelodysplastic syndromes (MDS). CD34(+) stem cells from healthy subjects were cultured with erythropoietin, IL-3 and stem cell factor, and thereby expanded approximately 300-fold. When these cultures were transduced with a lentiviral vector expressing GFP as a reporter gene, 70% glycophorin(+) cells were GFP(+). Although proliferation and levels of transduction were reduced in cultures of CD34(+) stem cells from patients with myelodysplastic syndromes, 50% of glycophorin(+) cells became GFP(+), amongst which 30% were sideroblastic erythroid precursors. This study demonstrates that lentiviral vectors are capable of efficiently transducing MDS precursors and offers new perspectives to investigate the influence of specific genes on normal erythroid differentiation. This may eventually help to correct defects in patients suffering from myelodysplastic syndromes.

Adult↗
PubMed2001

Hypothesis for generation of the unstable Hb Bucuresti (beta 42 Phe-->Leu) mutation.

INTRODUCTION: Unstable hemoglobin disorders are characterized by a congenital, mostly familial chronic hemolytic anemia with episodes of severe hemolysis during febrile illnesses. Usually, isopropanol and heat stability tests lead to the diagnosis which is confirmed by protein and gene sequencing. Generation of the mutations is still a subject of controversy. PATIENT, MATERIALS AND METHODS: We describe a 6-year-old Swiss child with congenital hemolytic anemia and a negative family history. Hemoglobin was studied by IEF, HPLC reverse phase chromatography, heat stability and isopropranol tests. DNA was sequenced in both coding and non-coding strands. RESULTS: An unstable Hb was diagnosed on the basis of positive heat stability and isopropranol tests. The TTT-->TTG mutation at codon 42 corresponding to a Phe-->Leu substitution was found on DNA sequencing. Paternity was confirmed indicating that we are dealing with a new mutation. CONCLUSION: So far, three different mutations at codon 42 of the beta-chain, and two at the corresponding position of the alpha-chain have been described, all leading to a hemolytic anemia. These mutations can either represent random phenomena occurring at an important location in the heme pocket, or may be secondary to the two highly homologous zones present in this region. These homologous zones may indicate a hot spot for point mutations created by abnormal crossing over or formation of loops, and an imperfect DNA repair process.

Amino Acid Substitution↗
PubMed2000

Hereditary hyperferritinaemia cataract syndrome: does it exist in Switzerland?

Recent research in iron metabolism has revealed the existence of iron-responding elements in the 5'UTR of the mRNA of ferritin. Binding of these structures with iron-regulatory proteins regulates ferritin synthesis within the cell, according to the intracellular iron level. Several mutations of the iron-responding elements located at the 5'UTR of the L-ferritin subunit, which lead to the hereditary hyperferritinaemia cataract syndrome, an autosomal dominant hereditary disease, have been described. Patients with congenital bilateral nuclear cataract present high serum ferritin (360-2264 micrograms/l) in the absence of iron overload. The purpose of our study was to look for this syndrome in Switzerland and in particular in the Geneva population. About 3000 cases of cataract operated on during a 4-year period (1995-1998) in the University Clinic of Ophthalmology were screened. We found 135 patients operated on before the age of 51 years. However, only 19 had bilateral nuclear cataract. 15 patients agreed to undergo iron screening. In 2 of them, a slight elevation of ferritin (267 micrograms/l in a female, 416 micrograms/l in a male) was found in the absence of iron overload. In both cases there is a positive family history of cataract. DNA sequencing analysis in these patients showed a normal nucleotide sequence of the whole iron-responding elements region. One of them (male) was found to present the codon 63 mutation at HFE gene in the heterozygous state. Our local study indicates that hereditary hyperferritinaemia cataract syndrome is extremely rare in Switzerland. However, similar studies should be carried out in other regions of the country. Iron status evaluation and ferritin level monitoring should become routine examinations in all new cases presenting with bilateral nuclear cataract before the age of 50 years.

5' Untranslated Regions↗
PubMed2000

Thalidomide in patients with advanced multiple myeloma.

INTRODUCTION: Recently, a report has suggested the efficacy and safety of thalidomide in refractory multiple myeloma. In an attempt to assess the efficacy and tolerance of thalidomide in advanced multiple myeloma (on behalf of the Intergroupe Franchophone dy Myelome (IFM)), we report the preliminary experience of the IFM with this drug. MATERIALS AND METHODS: Patients with advanced multiple myeloma (n=27) were treated with an oral dose of thalidomide (median 400 mg/day). At the start of treatment, all patients had active disease and 20 patients had received at least one autologous transplantation. RESULTS: Median follow-up was 105 days from the first administration. The serum and/or urine levels of the M-component were reduced by at least 75% in four patients including one patient with a >90% reduction, by at least 50% in five patients and by at least 25% in three patients, giving a total response rate of 45% (12 out of 27 patients). Nine patients had stable disease and six patients had progressed disease. Short-term side-effects of thalidomide were generally moderate. CONCLUSION: This study confirms that thalidomide is an effective agent in patients with advanced myeloma.

Agranulocytosis↗
PubMed2000

Hemochromatosis gene mutations in chronic hepatitis C patients with and without liver siderosis.

Chronic hepatitis C is often associated with liver iron overload, which may affect the long-term prognosis and the response to antiviral treatment. The occurrence of hemochromatosis (HFE) mutations were studied to determine whether may contribute to the liver iron overload of chronic hepatitis C patients. The prevalence of two HFE mutations (C282Y and H63D) in 120 chronic hepatitis C patients was determined and the findings were correlated with clinical, histological and virological features. Hepatic iron was determined semiquantitatively by a histochemical hepatic iron index, defined as the ratio of a histochemical staining score to the patient's age, after correction for heterogeneous lobular iron distribution. Serum hepatitis C virus (HCV) RNA was measured by bDNA assay and typed by restriction fragment length polymorphism. Liver HCV RNA was measured by a semi-quantitative strand-specific reverse transcription-polymerase chain reaction (RT-PCR). Excess liver iron was stained in the liver of 36 patients (30%). Siderotic patients had the same geographic origin, serum and liver HCV RNA levels and H63D and C282Y mutations frequency as non-siderotic patients. However, siderotic patients were older (P = 0.015), more frequently males (P = 0.02), less frequently infected with HCV genotype 3 (P = 0.037) and had a higher liver fibrosis score (P = 0.008). The liver iron content did not correlate with the serum or liver HCV RNA titers. Ten of the 36 patients with liver siderosis had neither a history of excess alcohol intake, multiple transfusions, or HFE mutations. In conclusion, the pathogenesis of the liver iron overload in chronic hepatitis C patients cannot be fully explained by the occurrence of HFE mutations. The exact mechanism of iron accumulation in these patients therefore remains unexplained.

Adult↗
PubMed2000

Increased apoptosis in acquired sideroblastic anaemia.

Idiopathic acquired sideroblastic anaemias (IASAs) form a subgroup of the myelodysplastic syndromes and are characterized by mitochondrial iron accumulation, bone marrow erythroid hyperplasia and decreased peripheral red blood cell counts. Increased intramedullary apoptosis of erythroid precursors is presumed to constitute the pathophysiological mechanism explaining this ineffective erythropoiesis, but if and how mitochondrial dysfunction is implicated in this process is currently unknown. We therefore studied bone marrow precursor cells obtained from nine patients with IASA for (i) caspase 3 activity, (ii) numbers of Annexin V- and 7-amino-actinomycin-positive cells, (iii) numbers of cells with diminished mitochondrial membrane potential, Delta Psi(m), and (iv) numbers of cells producing reactive oxygen species (ROS), and we compared the results with those of five normal bone marrow samples. Compared with controls, we found increased caspase 3 activity in all IASA samples, which correlated with increased numbers of Annexin-V-positive cells (r = 0.7). Analysis of different subpopulations showed increased apoptosis in erythroid populations compared with myeloid and/or lymphoid populations in five out of nine cases, and increased apoptosis in the last two populations in four out of nine cases. As evidence of mitochondrial dysfunction, Delta Psi(m) was found to be diminished in the erythroid subpopulations of all cases of IASA (66.6 +/- 17% vs. 34.6 +/- 12% in normals). Delta Psi(m) decrease was correlated to Annexin V positivity (r = 0.7). Astonishingly, no difference was found between IASA and normal bone marrows with regard to the number of ROS-producing cells. In fact, both groups exhibited a similar low proportion of ROS production (10.3 +/- 7% in normals vs. 6.8 +/- 5% in IASA). Taken together, our results show that mitochondria are clearly implicated in the apoptotic process in IASA patients. Whether this is a result of an intramitochondrial defect (e.g. Fe accumulation, secondary to mitochondrial or nuclear DNA mutations) or is secondary to an extracellular stimulus [e.g. tumour necrosis factor (TNF), Fas ligand (FasL)] remains to be determined.

Adult↗
PubMed1999

Hb Iraq-Halabja beta10 (A7) Ala-->Val (GCC-->GTC): a new beta-chain silent variant in a family with multiple Hb disorders.

A patient originating from Iraq was referred to our laboratory upon suspicion of a hemoglobinopathy. Routine hematological tests revealed a microcytic and slightly anemic phenotype with an elevated HbA2 suggestive of beta-thalassemia. Samples were obtained for several members of the family which upon examination revealed highly heterogeneous phenotypes that prompted us to investigate the case further. Sequencing of the beta-globin gene and alpha cluster mapping in the propositus and his brother showed a previously undescribed beta-globin variant:Hb Iraq-Halabja, beta10(A7) Ala-->Val (GCC-->GTC), associated with beta0-thalassemia IVS-2 nt1 G-->A and either alpha-thal-2-3.7 kb deletion (brother), or alpha-globin gene triplication anti-3.7 kb type (propositus). Detailed functional studies of the variant gave a normal oxygenation curve, a normal heterotopic action of 2,3 DPG, and normal heat stability and isopropanol precipitation tests. The variant shows a clear difference in migration properties compared to normal beta-chain only when run on PAGE urea Triton. As expected, alpha/beta-globin mRNA ratios were influenced by the concomitant presence of an alpha-globin gene pathology and the beta0 thalassemia and not by the presence of the beta-globin variant which apparently is clinically silent.

Adult↗
PubMed1999

Iron overload in patients with sideroblastic anaemia is not related to the presence of the haemochromatosis Cys282Tyr and His63Asp mutations.

Forty Caucasian patients with primary acquired sideroblastic anaemia (SA), were investigated for the presence of the Cys282Tyr and/or His63Asp mutation as possible cofactor(s) for iron overload. One patient was heterozygous for the Cys282Tyr mutation and 13 heterozygotes and one homozygote for the His63Asp mutation were found (no difference compared with controls). SA patients with normal codon 63 had a mean ferritin level of 923+/-815 microg/l whereas those with codon 63 mutation had 769+/-577 microg/l (P=0.64). We conclude that ineffective erythropoiesis with no associated mutation in the HFE gene can lead to iron overload in SA patients.

Aged↗
PubMed1999

Severe inclusion body beta-thalassaemia with haemolysis in a patient double heterozygous for beta(0)-thalassaemia and quadruplicated alpha-globin gene arrangement of the anti-4.2 type.

We describe a new case of an association of alpha-globin gene quadruplication of the anti-4.2 type with beta(0)-thalassaemia. The patient, a young woman of mixed Brazilian-Portuguese origin, suffered from chronic haemolytic anaemia with splenomegaly. Bone marrow supravital staining with brilliant cresyl blue and electron microscopy studies showed large inclusion bodies in about 3% of erythroblasts. Upon immunofluorescent staining these inclusions reacted with a monoclonal antibody to alpha- but not to beta-globin. Analysis of alpha-globin cluster by Southern blotting showed the presence of pathologic fragments specific for the anti-4.2 alpha-globin gene quadruplication. Alpha/beta mRNA ratio was higher than in cases combining alpha-globin triplication and beta(0)-thalassaemia or in cases of beta(0)-thalassaemia heterozygous state alone (18, 14.7 and 10.1 respectively). Our data confirmed the hypothesis that the clinically detectable haemolysis in this beta(0)-thalassaemic patient was due to an unusually high amount of precipitated alpha-globin in erythroid precursors. This considerable excess of alpha-globin chains was due partly to the beta-globin deficit caused by the presence of the beta(0)-thalassaemic gene, but also to the presence of 6 active alpha-globin genes resulting from alpha-globin gene quadruplication in one chromosome.

Anemia, Hemolytic↗
PubMed1999

Benefit of prestorage leukocyte depletion of single-donor platelet concentrates.

BACKGROUND AND OBJECTIVES: The presence of contaminating white blood cells (WBCs) in platelet concentrates is associated with transfusion reactions and may adversely alter the quality of platelets during storage. Leukocyte depletion by filtration of platelets has been increasingly used to avoid these complications. However, the best time for filtration and the benefits of filtering single-donor platelet concentrates (thrombapheresis, TH) have yet to be clearly defined. METHODS: In a randomized study of 202 TH collected with an Autopheresis C system, we determined whether prestorage filtration (preSF) of WBCs from TH as compared with poststorage (bedside) filtration (postSF) resulted in a better product. Levels of cytokines and C3a accumulating in the medium during storage, platelet activation state, in vivo platelet recovery, and transfusion reactions were compared in pre- and poststorage products. RESULTS: As compared to preSF, significantly more postSF TH had detectable levels of tumor necrosis factor-alpha (TNF-alpha; 47 vs. 15%; p<0.0001) and interleukin 6 (13 vs. 3%; p = 0.02), lower pH (p<0.0001) and decreased levels of C3a (910 vs. 2,000 pg/ml; p<0. 0001). Furthermore, platelet activation was increased in postSF TH (p = 0.022). PostSF TH tended to plug the bedside filter (27% of postSF TH delivered) from day 3 onward. There was also a significant difference in platelet recovery, postSF TH showing a lower corrected count increment (CCI; p = 0.0055) when taking into account the postSF TH that plugged filters (CCI = 0), but no difference when plugged TH were excluded. A correlation could be established between TNF-alpha levels and poor in vivo recovery (p<0.0001). Febrile nonhemolytic transfusion reactions were low in both groups (4 and 9%). CONCLUSION: These results indicate a benefit of preSF TH as compared with postSF TH based on the following parameters: decrease in cytokine levels, less platelet activation, maintenance of higher pH, and more efficient use of stored platelets (27% of postSF TH were lost because of plugging of filters). These results apply particularly to the Autopheresis C systems with its high initial WBC content.

Blood Component Removal↗
PubMed1998

[Effect of administration of recombinant human erythropoietin in acute normovolemic hemodilution on transfusion needs during total hip prosthesis implantation].

Acute normovolaemic haemodilution (ANH) is used to avoid perioperative blood loss and consists of the withdrawal of whole blood just before or just after anaesthesia induction and its simultaneous replacement by synthetic colloids and crystalloid solutions. In an attempt to improve the efficiency of this technique while at the same time avoiding cardiovascular complications, we set up a pilot study to test the association of rHuEpo/ANH during elective surgery for total hip replacement. Five patients (3 males, 2 females) were included in this study. The amount of whole blood drawn was 3 x 450 ml from the men and 2 x 450 ml from the women. Before blood was taken, the mean increase in haemoglobin was 1.2 +/- 0.9 g/dl and mean increase in reticulocytes 106 +/- 34 G/l. No patient received homologous transfusion during the perioperative period; 3 patients received the totality of predonated blood and one patient 2 of the 3 units taken. The mean fall in haemoglobin at day 1 post-surgery was 3.6 g/dl. In conclusion, the stimulation of erythropoiesis by rHuEpo in the pre-surgery phase led on average to a 1 g/dl gain in haemoglobin, permitting an isovolaemic withdrawal of 900 to 1350 ml of blood depending on body weight without the development of severe anaemia. It was thus possible to perform total hip replacement in all the patients without homologous blood support and with a post-surgery haemoglobin value of > 10 g/dl. This protocol should be further tested in a prospective randomised study (rHuEpo versus placebo) in order to assess the real benefit of rHuEpo.

Adult↗
PubMed1998

Blood transfusion requirements in otolaryngology--head and neck surgery.

BACKGROUND: Blood requirements for Head and Neck surgical procedures have not been studied carefully. In order to set up an autotransfusion program, the blood loss and transfusion requirements should be known precisely. METHODS: The blood bank database was used to determine which Head and Neck procedures required blood transfusion during the previous 5 years. A list of 10 transfusion-associated operations was established, the records of all patients who underwent these procedures during a 5-year period were reviewed, and average the blood loss and number of units transfused determined. RESULTS: All procedures were for cancer resection. The operations were classified in 3 groups according to their transfusion probability: high (> 80%), low (< 5%) and moderate. For the moderate transfusion group, age, preoperative hemoglobin, and past medical history of cardiac and pulmonary disease were associated with higher incidence of transfusion. An average delay of 3 weeks was found between the diagnosis and the actual surgery. CONCLUSION: The transfusion requirements of Head and Neck surgical procedures could be safely met by an autotransfusion protocol, given the average delay of 3 weeks between diagnosis and surgery.

Aged↗
PubMed1997

[Long-term survival of 2 cases of hemochromatosis respectively homozygous for His63Asp and Cys282Tyr mutations].

A 45-year-old Greek patient was found to have a moderate iron overload (ferritin 1213 micrograms/l, serum iron 21.5 mumol/l, transferrin saturation 40%). He underwent 12 phlebotomies of 450 cc over an 8-year period and ferritin was normalized (267 micrograms/l) after the seventh. Study of the HLA-H gene in leukocyte DNA showed that the patient is homozygous for the His63Asp mutation while no modification was found at position 282. This case is compared with that of a 50-year-old Swiss male presenting a severe iron overload (ferritin 7660 micrograms/l, serum iron 36.5 mumol/l, transferrin saturation 97%). Although this patient has undergone 77 phlebotomies (450 cc each time) over a 2-year period, he continues to have a high ferritin level (2200 micrograms/l). HLA-H gene analysis showed the absence of codon 63 mutation and the presence of Cys282Tyr mutation in the homozygous state. The study of these two cases indicates that penetrance of the His63Asp mutation in the homozygous state is very low as compared to Cys282Tyr and results in moderate iron accumulation, probably without organ damage. This genotype must be looked for whenever moderate iron overload is present.

DNA Mutational Analysis↗
PubMed1997

[Differential anemia diagnosis].

Anemia is among the most frequently encountered pathologies in medical practice. In most cases the underlying cause is easily defined, as for example iron deficiency or vitamin B12 deficiency. However, cases with a more complex picture of anemia should also be recognised by the practitioner and referred within due time to the specialist. The aim of the present review is to provide the tools for a work-up of anemias which is at the same time rational as well as precise. A precise diagnosis is the prerequisite for an effective treatment of any given anemia. We strongly feel that no anemic patient should be treated by trial and error.

Anemia↗