PubMed Health⌕ Search

Biomedical subjects

U Lippi

Publications and source records attributed to U Lippi.

At least 19 recordsLinked to original sources
PubMed1996

Deficiency of vitamins E and A in cystic fibrosis is independent of pancreatic function and current enzyme and vitamin supplementation.

UNLABELLED: The aim of this study was to evaluate to what extent serum vitamins A and E cystic fibrosis are affected by the underlying disease, pancreatic sufficiency or insufficiency, meconium ileus, nutritional status, age and treatment (enzyme and vitamin supplementation). Serum vitamin A and E levels were determined by high performance liquid chromatography in 210 cystic fibrosis patients, subdivided according to clinical condition into four subgroups (unsupplemented pancreatic insufficiency, supplemented meconium ileus, pancreatic sufficiency, supplemented pancreatic insufficiency) and compared with 42 control subjects. Vitamin A and E levels were generally lower in cystic fibrosis patients than in controls (P < 0.002 and P < 0.001 respectively). Subjects with pancreatic insufficiency regularly receiving enzyme and vitamin supplementation had significantly lower vitamin A (P < 0.05) and vitamin E (P < 0.01) levels than controls. In subjects with pancreatic sufficiency only vitamin A was significantly lower than in controls (P < 0.01). Vitamin levels were not age-dependent in cystic fibrosis, and no significant correlation with standardized body weight (Z-score) was observed. CONCLUSION: Cystic fibrosis patients show a clear tendency to vitamin A and E deficiency, irrespective of pancreatic function, body weight and standardized supplementation with pancreatic extract and liposoluble vitamins. Since the clinical significance of this deficiency is still not clear, longitudinal studies of cystic fibrosis patients with and without adequate vitamin supplementation are required.

Adolescent↗
PubMed1994

A simple assessment of human neutrophil adhesiveness.

The adhesiveness of human polymorphonuclear leukocytes was assessed in serum-coated polystyrene spectrophotometric cuvettes. Capped cuvettes, containing no more than 2 x 10(6) resting or concanavalin A-treated (100 micrograms/ml) polymorphonuclear leukocytes, were laid horizontally and subjected to three 90 degrees rotations on their major axis at fixed times. After incubation at room temperature, non-adherent cells remaining in suspension were counted on the Coulter counter STKS hematological analyzer. After a 16-min incubation (4 min each side of the cuvette) the adhesion of concanavalin A-activated neutrophils ranged from 98% to 100% and the adhesion of resting neutrophils from 30% to 35% (mean 32.4 +/- 2.2%, n = 10). An 8-min incubation (2 min each side) led to approximately 50% adhesion of concanavalin A-activated neutrophils (mean 49.9 +/- 2.2%, range 46%-54%, n = 16), whereas the adhesion of resting cells was about 21% (mean 21.4 +/- 1.6%, range 19%-24%, n = 16). The variation in percentage adhesion in repeated assays did not exceed 4% using concanavalin A-activated cells and 7.5% with resting neutrophils. The procedure is very rapid, easy to perform and precise, and no special apparatus or glassware is necessary. The method also allows microscopic evaluation of shape changes of adherent neutrophils through the clear sides of the cuvettes.

Animals↗
PubMed1994

Assessment of neutrophil aggregation by Coulter STKR and STKS haematological analysers.

We have studied an alternative method to aggregometry for the assessment of human polymorphonuclear (PMN) leucocyte aggregation. This simple, rapid and reliable procedure counts unaggregated cells on both Coulter STKS and STKR haematological analysers by the impedance principle. Aggregation of PMN was induced by 15 min incubation with fresh autologous serum (FAS) after a 10 min phorbol myristate acetate (PMA) activation of neutrophils in small aliquots (0.25 ml) of suspension containing about 4.0 x 10(9) PMN/1. Differences (x 100) between count of resting and PMA+FAS treated neutrophils/count of resting PMN reflect percent aggregation. By this procedure, PMN aggregation did not occur in autologous plasma from EDTA anticoagulated whole blood; it was partially inhibited by hydrocortisone, whereas inactivated or Zymosan activated sera gave values similar to those from FAS induced aggregation. PMA aggregation was dependent on Ca2+ + Mg2+ concentration. Intra-assay analytical variability did not exceed 4% on either instrument. Reference values (n = 20) of percent PMN aggregation were 50.7 +/- 4.7 on STKS and 47.1 +/- 4.8 on STKR. Most probably, the interindividual variance was due to the physiological variability of Mg2+ and/or Ca2+ concentrations in FAS. Thus, this procedure reflects the true PMN aggregability status in a given subject, and in a given electrolyte environment.

Adult↗
PubMed1994

High light scatter by neutrophils in the Bayer-Technicon H*2 analyzer: a screening test of morphologically defective responsiveness to in vitro chemotactic stimulation.

The Bayer-Technicon H*2 haematological analyser provides differential white blood cell count, including the assay of polymorphonuclear leukocytes by light scattering and the absorbance increase following the cytochemical reaction for myeloperoxidase. The mean value of polymorphonuclear leukocytes scatter, which reflects polymorphonuclear leukocytes volume, is printed in a separate report "for laboratory use only" as a ybar value in arbitrary units. In certain patients neutrophils displayed an unreported correlation between polymorphonuclear leukocytes high ybar basal values (> or = 37.00 arbitrary units) (determined on the H*2) and a defective response in vitro to the chemoattractant, formyl-methionyl-leucyl-phenylalanine (determined by microscopic evaluation of polymorphonuclear leukocytes shape change (polarization)). The patients showing no polymorphonuclear leukocyte response or a defective one to formyl-methionyl-leucyl-phenylalanine were all affected by "Systemic Inflammatory Response Syndrome (SIRS)". Therefore the predictive value of the positive test for SIRS is 100%. On the other hand 8.8% of SIRS patients had polymorphonuclear leukocytes < 37.00 arbitrary units of ybar basal value and a "normal" response to formyl-methionyl-leucyl-phenylalanine; the predictive value of the negative test being 90%. Since we demonstrated in vitro a dose-dependent deactivation of endotoxin or lipopolysaccharide-pretreated polymorphonuclear leukocytes, the "normal" response to formyl-methionyl-leucyl-phenylalanine of the "false negative" cases may occur because the endotoxaemia in these patients is too low to prevent it.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Size↗
PubMed1993

Multicenter evaluation of Reflotron direct dry-chemistry assay of high-density lipoprotein cholesterol in venous and fingerstick specimens.

The Reflotron HDL Cholesterol test (Boehringer Mannheim GmbH) directly separates and analyzes high-density lipoprotein (HDL) cholesterol in plasma collected with EDTA in an integrated dry-reagent system suitable for alternative site testing of lipoproteins. We describe a multicenter evaluation of this test by two US and six European laboratories experienced in lipid analysis. Each laboratory compared the Reflotron with the same conventional wet-chemistry method, Boehringer phosphotungstate-Mg2+ precipitation with enzymatic cholesterol assay. Imprecision was within accepted guidelines, with CVs of < or = 8% for fresh and frozen plasmas (median CV 1.7-3.9%) and for lyophilized sera (median CV 3.8-4.7%), similar to those of the conventional method. Results of linear-regression analysis were as follows: Reflotron HDL Cholesterol = 1.03 conventional - 3.9 mg/L, r = 0.987. The Reflotron results were somewhat low in the two US laboratories, demonstrating the need for general standardization of methods for measuring HDL cholesterol. Results from capillary fingerstick plasma agreed well with those from venous-derived plasma; capillary = 1.04 venous + 4.5 mg/L, r = 0.967. The system is relatively insensitive to interference from hemoglobin (< or = 0.75 g/L), ascorbic acid (< or = 0.3 g/L), bilirubin (< or = 50 mg/L), cholesterol (< or = 3.5 g/L), and triglycerides (< or = 4 g/L). The relative ease of operation and the rapid availability of results (within 90 s for plasma collected in EDTA) make the method appropriate for use by well-trained, but not necessarily technical, operators in the physician's office or other alternative sites.

Aminopyrine↗
PubMed1992

Volume, conductivity, and scatter changes of activated polymorphonuclear leukocytes: an estimation by Coulter Counter STKS analyzer.

Suspensions of phorbol myristate acetate-activated polymorphonuclear leukocytes were analyzed with a Coulter Counter STKS hematological analyzer. Phorbol myristate acetate activation induced an increase in polymorphonuclear leukocyte volume and conductivity, while scatter was unchanged. Phorbol myristate acetate-activated neutrophils in a suspension containing nitroblue tetrazolium showed increased scatter. The rise in scatter was phorbol myristate acetate dose dependent, completely inhibited by diphenylene iodonium and partially by dimethyl sulfoxide, two inhibitors of NADPH oxidase. Zymosan-activated polymorphonuclear leukocytes were notably larger with a characteristic position on discriminant function 1 display (volume versus scatter) of the analyzer. Volume and conductivity changes were seemingly inexplicable features of phorbol myristate acetate activation. The rise in scatter was produced by cytoplasmic precipitation of reduced nitroblue tetrazolium and thus by O2-generation in phorbol myristate acetate-activated neutrophils. Zymosan phagocytosis was responsible for the notable rise in polymorphonuclear leukocyte volume. The analysis of activated polymorphonuclear leukocytes by Coulter Counter STKS may provide useful information on their activation and a pragmatic approach for studying function.

Biphenyl Compounds↗
PubMed1992

Serum low density lipoprotein separation: a simple procedure.

Reference methods for serum low density lipoprotein (LDL) separation are time-consuming and the salts used in density-gradient ultracentrifugation may cause chemical and/or immunological changes in the lipoprotein structure. A method has been developed to provide native LDL suitable for chemical and immunochemical studies. The three step procedure involves firstly the separation of very low density lipoproteins by non-density adjusted ultracentrifugation, secondly the separation of low from high density lipoproteins by LDL precipitation with PEG-6000, and finally the re-dissolution of the pellet in NaCl 150 mmol/l. The effectiveness of LDL separation, as well as the preservation of the electrophoretic mobility of the LDL molecules, was verified by electrophoresis in agarose gel, and the maintenance of the immunochemical reactivity of apolipoprotein B was verified by an immunochemical assay.

Fractional Precipitation↗
PubMed1990

Advantages of a new anticoagulant in routine hematology on the Coulter Counter S-Plus STKR analyzer.

The authors report the advantages of a new anticoagulant-antiaggregant mixture that avoids the deleterious effects of ethylenediaminotetraacetic acid (EDTA) on mean platelet volume and also prevents EDTA-induced platelet clumping. It is suitable for routine cell counting and sizing with the Coulter Counter S-Plus STKR. The values of the common hematologic parameters agree well with those from EDTA-treated samples and are stable for at least eight hours after sampling.

Anticoagulants↗
PubMed1988

Determination of high density lipoprotein cholesterol in venous and capillary whole blood.

A procedure is presented and evaluated for separation of plasma high density lipoprotein from either capillary or venous whole blood. The lipoprotein is separated by adding 50 microliter of sample to 250 microliter of 0.15 M NaCl solution containing 99.9 g/l polyethyleneglycol 6000, 0.0374 g/l dextran sulfate (Mr 15,000) and 2.6 mM Mg2+. After gentle mixing for a few minutes and standing 10 min at room temperature, mixtures are centrifuged (1,500 g) for 10 min and cholesterol is measured on 200 microliter of supernatant by an enzymatic-colorimetric method. Comparison studies demonstrate a good correlation between high density lipoprotein cholesterol in plasma and capillary or venous whole blood. The procedure is simple, has the advantage of using either K3-EDTA-anticoagulated whole blood, without the need of centrifugation, or capillary whole blood which can also be collected away from the laboratory.

Capillaries↗
PubMed1987

Unpredictable effects of K3 EDTA on mean platelet volume.

The changes of mean platelet volumes (MPVs) begin immediately upon exposure of the blood to K3EDTA, and differences from sample to sample are unpredictable, predominantly in the first two hours from the venipuncture. MPVs variations can range from -25 to 23.1% in respect to MPVs in untreated whole blood immediately processed. These results were obtained by a new electrooptical device (Technicon H X 1) that provides complete blood cell counting and sizing. If whole blood is collected and diluted with a reagent used by the instrument to sphere and fix red blood cells and platelets, MPVs values do not change significantly within 180 minutes from venipuncture. This approach allows one to study the true values of MPVs on Technicon H X 1.

Blood Cell Count↗
PubMed1987

Fully automated cytochemistry on whole blood smears using the Technicon Hemalog D or Technicon H6000/Autoslide: myeloperoxidase staining methods.

Two methods for performing fully automated cytochemical myeloperoxidase stains on whole blood smears using the Technicon Autoslide are described. The Autoslide is a device designed to operate synchronously with the Technicon Hemalog D or H6000 systems to produce whole blood smears suitable for microscopic examination at the rate of 90 processed slides per hour. Both methods (with benzidine base and 4-chloro-1-naphthol as chromogens) demonstrated myeloperoxidase activity in polymorphonuclear leukocytes with high specificity and sensitivity. The methods provided cleared permanent cytochemical stains and avoided skin exposure to potentially infectious specimens during the smearing and staining procedures. The standardization of cytochemical procedures and the analytical speed of the device make these automated cytochemical methods suitable for use in many large hematological laboratories.

Benzidines↗
PubMed1986

Multiple myeloma with serum IgM kappa and Bence Jones lambda biclonal gammopathy.

We report a rare finding: IgM kappa and Bence Jones lambda double gammopathy in serum of a 80-year-old man with untreated symptomatic multiple myeloma. The unusual findings are confined to the laboratory studies demonstrating also a Bence Jones lambda proteinuria, high erythrocyte sedimentation rate (113 mm/h), and anemia. The synthesis of the different light chains seems to occur in separate cellular clones.

Aged↗