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1.
Clin Ter ; 172(2): 151-157, 2021 Mar 15.
Article in English | MEDLINE | ID: mdl-33763678

ABSTRACT

BACKGROUND AND AIM: Appropriate end of life (EOL) management in Internal Medicine wards is challanging. The aim of this study was to analyze the burden of an educational program on EOL management in a Internal Medicine ward. Materials and methods: We retrospectively analysed characteristics and management of patients consecutively died in an italian Internal Medicine ward along one year. We compared demographic, co-morbidity, pharmacological treatment in the last 48-hours of life and procedures during hospital stay in patients died six months before and after an educational program on palliative cares and EOL management addressed to a team of physicians and nurses. RESULTS: Study population was composed by 354 patients (190 females), with mean age ± DS 83.5 ± 10.6 years, one half admitted after the educational program. Eighty-four percent of deaths was exepected in the last 48 hours before exitus. Demographic characteristics and causes of hospitalization were not different before and after educational program. After the educational program the sharing of palliative care program with patient, relatives and/or caregivers (97.7% vs 85.8%, p=0.0001) and written order to withdrawal vital parameters relevation (39.5% vs 22%, p=0.0005) significantly increased, while difference in pharmacological classes prescribed in the last 48 hours of life was not find. Blood (54.8% vs 67.2%, p=0.0219) and arterial gas analysis (28.8% vs 39.5%, p=0.0435) samples in the last 48 hours of life were significantly reduced. Radiological and/or endoscopic examinations, red cells or platelets transfusion were reduced and palliative therapy was increased, despite difference between the two periods was not statistically significant. CONCLUSION: Educational program in Internal Medicine wards aimed to improve skills could contribute to make EOL management more appropriate and patient-oriented and it should be strongly encour-aged.


Subject(s)
Education, Medical, Continuing/organization & administration , Education, Nursing, Continuing/organization & administration , Hospitals , Internal Medicine/education , Terminal Care/organization & administration , Aged , Aged, 80 and over , Caregivers , Comorbidity , Death , Female , Humans , Italy , Length of Stay , Male , Palliative Care/organization & administration , Retrospective Studies , Socioeconomic Factors
2.
Clin Ter ; 169(6): e287-e291, 2018.
Article in English | MEDLINE | ID: mdl-30554250

ABSTRACT

BACKGROUND: Guidelines recommend triple therapy (TT) with ACE inhibitors or ARBs, beta-blockers and mineralcorticoid receptor antagonists in symptomatic heart failure patients with ejection fraction <35 % (HFrEF). Nevertheless, many patients remain untreated. This study was aimed to evaluate the use of TT in HFrEF patients discharged from internal medicine wards of Tuscany, Italy. METHODS AND RESULTS: We analyzed the database of a multicenter observational study which included 770 patients consecutively hospitalized for HF in 32out of 36 Internal Medicine Units of Tuscany, Italy. The value of ejection fraction was available in 490 of the 725 patients discharged alive. Of the 117 patients with HFrEF, only 46 (39.3%) were on TT at discharge while 71 (60.7%) were not. In the latter group we observed a significantly greater percentage of patients with cognitive deficit (25.3% vs 10.8%, p=0.05). In the same group there was a slightly greater percentage of patients with hypertension (61.9% vs 58.6%), diabetes (43.6% vs 36.9%), GFR<60 ml/min (74.6% vs 67.3%), anemia (52.1% vs 45.6%) and atrial fibrillation (40.8% vs 34.7%), but the differences were not statistically significant. CONSLUSIONS: These results indicate that TT is underutilized in internal medicine wards of Tuscany. Untreated patients had a greater rate of cognitive deficit and were probably sicker, more complex and fragile.


Subject(s)
Drug Utilization/statistics & numerical data , Guideline Adherence/statistics & numerical data , Heart Failure/drug therapy , Stroke Volume/physiology , Adrenergic beta-Antagonists/therapeutic use , Aged , Angiotensin Receptor Antagonists/therapeutic use , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Cross-Sectional Studies , Female , Heart Failure/physiopathology , Humans , Italy , Male , Middle Aged , Patient Discharge , Practice Guidelines as Topic , Retrospective Studies
3.
Eur J Intern Med ; 33: 47-54, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27289494

ABSTRACT

BACKGROUND: The optimal management of major bleeding associated with vitamin K antagonists remains unclear. OBJECTIVES: The aim of the study was to assess the determinants of outcome of vitamin K antagonists-associated major bleeding and the outcome of bleeding in relation with the therapeutic management. METHODS: Patients hospitalized for major bleeding while on vitamin K antagonists were included in a prospective, cohort study. Major bleeding was defined according to the criteria of the International Society of Thrombosis Haemostasis. The primary study outcome was death at 30days from major bleeding. RESULTS: 544 patients were included in this study, of which 282 with intracranial hemorrhage. Prothrombin complex concentrates were used in 51% and in 23% of patients with intracranial hemorrhage or non-intracranial major bleeding, respectively (p<0.001); fresh frozen plasma was used in 7% and in 17% of patients with intracranial hemorrhage or non-intracranial major bleeding (p<0.001). Death at 30days occurred in 100 patients (18%), 72 patients with intracranial hemorrhage and 28 patients with non-intracranial major bleeding. Age over 85years, low Glasgow Coma Scale score and shock were independent predictors of death at 30days. Invasive procedures were associated with decreased risk of death. CONCLUSIONS: Among the patients hospitalized for major bleeding while on vitamin K antagonists, the risk for death is substantial. The risk for death is associated with the clinical severity of major bleeding as assessed by the GCS score and by the presence of shock more than with the initial localization of major bleeding (ICH vs other sites).


Subject(s)
Blood Coagulation Factors/therapeutic use , Fibrinolytic Agents/adverse effects , Intracranial Hemorrhages/mortality , Intracranial Hemorrhages/therapy , Vitamin K/antagonists & inhibitors , Adult , Aged , Aged, 80 and over , Anticoagulants/adverse effects , Disease Management , Female , Glasgow Coma Scale , Humans , International Normalized Ratio , Intracranial Hemorrhages/chemically induced , Italy , Length of Stay , Male , Middle Aged , Plasma , Prognosis , Proportional Hazards Models , Prospective Studies , Warfarin/adverse effects
4.
Water Sci Technol ; 58(9): 1789-96, 2008.
Article in English | MEDLINE | ID: mdl-19029720

ABSTRACT

This paper deals with the case of one of the most important industrial application of membrane technology in the world: the upgrading of the main industrial wastewater treatment plant (WWTP) of the petrochemical site of Porto Marghera, Northern Italy, completed on December 2005 and tested on September 2006. It describes the principal interventions of the plant upgrading and it discusses the removal obtained during the test periods for conventional pollutants as well as for micropollutants. The plant upgrading consisted of a series of improvements of the existing industrial WWTP, in order to increase the removal efficiency of the total suspended solids and the associate removal of ten micropollutant compounds, the so called forbidden substances. The most important intervention was the conversion of the existing activated sludge section into a membrane biological reactor, in order to guarantee adherence to the severe limits imposed by the special law issued to protect the Venice Lagoon, with particular reference to the mentioned 10 forbidden compounds. The experimental results and the numerous test-runs conducted confirmed the respect of the legal limits for the pollutants in the final effluent as well of the required removal rates for the different parameters. Therefore, the upgraded treatment plant was declared agreeing with the approved design.


Subject(s)
Environmental Restoration and Remediation/methods , Industrial Waste , Water Pollutants/isolation & purification , Italy , Metals/isolation & purification , Solvents/isolation & purification
5.
IEEE Trans Med Imaging ; 27(10): 1515-24, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18815103

ABSTRACT

A real-time hardware software 2-D vector Doppler system has been realized by means of the FEMMINA platform. The system operates by performing two independent 1-D Doppler estimations on the scan plane of a linear array probe along different directions; the probe is connected to a commercial scanner. The reconstructed velocity is presented in real-time as superposition on the conventional B-mode images. Two different scanning techniques have been implemented, in order to carry out the 2-D Doppler investigation in the area of interest. These techniques allow to use the system both in vivo and in vivo. An extensive set of simulations has been performed in order to establish a gold standard regarding vector Doppler 2-D techniques, and to be able to assess the performance of the 2-D Doppler system by comparing simulated and experimental results. The whole real-time 2-D vector Doppler system is fully certified as hospital equipment, and thus it can be employed to carry out an experimental characterization of the 2-D Doppler technique in the clinical environment.


Subject(s)
Echocardiography, Doppler/instrumentation , Image Enhancement/instrumentation , Image Interpretation, Computer-Assisted/instrumentation , Biomedical Research/instrumentation , Computer Systems , Echocardiography, Doppler/methods , Equipment Design , Equipment Failure Analysis , Image Interpretation, Computer-Assisted/methods , Reproducibility of Results , Sensitivity and Specificity
8.
Biochim Biophys Acta ; 1771(2): 139-46, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17234448

ABSTRACT

9-hydroxystearic acid (9-HSA) belongs to the class of endogenous lipid peroxidation by-products that greatly diminish in tumors, causing as a consequence the loss of one of the control mechanisms on cell division. We have previously shown that 9-HSA controls cell growth and differentiation by inhibiting histone deacetylase 1 (HDAC1) activity. In this paper our attention has not only been focused on HDAC1 inhibition but also on the hyperacetylation of other substrates such as p53, that is involved in inducing cell cycle arrest and/or apoptosis, and whose activity and stability are known to be regulated by posttranslational modifications, particularly by acetylation at the C-terminus region. 9-HSA administration to U2OS, an osteosarcoma cell line p53 wt, induces a growth arrest of the cells in G2/M and apoptosis via a mitochondrial pathway. In particular hyperacetylation of p53 induced by the HDAC1 inhibitory activity of 9-HSA has been demonstrated to increase Bax synthesis both at the transcriptional and the translational level. The subsequent translocation of Bax to the mitochondria is associated to a significant increase in caspase 9 activity. Our data demonstrate that the effects of 9-HSA on U2OS correlate with posttranslational modifications of p53.


Subject(s)
Osteosarcoma/metabolism , Signal Transduction , Stearic Acids/pharmacology , Tumor Suppressor Protein p53/metabolism , Acetylation , Apoptosis , Cell Line, Tumor , Cell Proliferation , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Humans , Promoter Regions, Genetic , Stearic Acids/toxicity , bcl-2-Associated X Protein/genetics
9.
Biochem Biophys Res Commun ; 354(2): 409-13, 2007 Mar 09.
Article in English | MEDLINE | ID: mdl-17227671

ABSTRACT

The use of agents targeting EGFR represents a new frontier in colon cancer therapy. Among these, mAbs and EGFR tyrosine kinase inhibitors seemed to be the most promising. However they have demonstrated scarce utility in therapy, the former being effective only at toxic doses, the latter resulting inefficient in colon cancer. This paper presents studies on a new EGFR inhibitor, FR18, a molecule containing the same naphthoquinone core as shikonin, an agent with great anti-tumor potential. In HT29, a human colon carcinoma cell line, flow cytometry, immunoprecipitation, and Western blot analysis, confocal spectral microscopy have demonstrated that FR18 is active at concentrations as low as 10 nM, inhibits EGF binding to EGFR while leaving unperturbed the receptor kinase activity. At concentration ranging from 30 nM to 5 microM, it activates apoptosis. FR18 seems therefore to have possible therapeutic applications in colon cancer.


Subject(s)
Apoptosis/drug effects , Colonic Neoplasms/drug therapy , Colonic Neoplasms/pathology , ErbB Receptors/antagonists & inhibitors , Naphthoquinones/chemistry , Protein Kinase Inhibitors/chemistry , Colonic Neoplasms/enzymology , Dose-Response Relationship, Drug , ErbB Receptors/metabolism , HT29 Cells , Humans , Microscopy, Confocal , Naphthoquinones/pharmacology , Protein Kinase Inhibitors/pharmacology
10.
J Chromatogr A ; 1129(1): 73-81, 2006 Sep 29.
Article in English | MEDLINE | ID: mdl-16887128

ABSTRACT

The application of reversed-phase high-pressure liquid chromatography under gradient conditions and electrospray ion trap mass spectrometry (LC-ESI-MS) to the analysis of global modification levels of core histones is described. The optimised LC-ESI-MS method was applied for the first time to the characterisation of histones extracted from HT29, a human colon cancer cell line. Eight histones (H1-1, H1-2, H2A-1, H2A-2, H2B, H3-1, H3-2, H4) were separated on a C4 stationary phase with complete resolution, never reached in previous HPLC-MS methods, by using a gradient elution with the combined presence of heptafluorobutyric acid and formic acid as acidic modifiers in the mobile phase. Heptafluorobutyric acid was found to improve selectivity, whereas the presence of formic acid decreased ion suppression. Histones eluted from the column were detected with an ion trap mass spectrometer with an electrospray source. The peak averaged mass spectra were reconstructed by Mag Tran 1.0 software and the mass of the various isoforms of histones were derived. Method validation was conducted by performing the same sample analysis by coupling LC-ESI to a quadrupole-time-of-flight mass spectrometer (Q-TOF). The number of histone forms and their mass were found to differ not significantly from those obtained by ion trap mass spectrometer. Also the relative modifications abundance within the same histone type was found following the same trend as the two mass analysers. This method was then applied to the characterisation of changes in histone modification in HT29, never analysed by LC-MS before, treated with histone deacetylase inhibitors such as valproate and sodium butyrate, also used in preclinical trials as anticancer drugs. In particular, both the inhibitors produced a significant increase in H4 histone acetylated forms: 89% increase of the diacetyl dimethyl H4 form was observed with 1mM valproate supplementation, whereas 5 mM butyrate led to a 68% increase of the same form. Triacetyl monomethyl H4 (11,377 Da) and triacetyl dimethyl H4 (11,390 Da) were found only in cells treated with butyrate. Selective changes of H3 histone were detected with butyrate, in agreement with recently reported western blotting studies. Modifications in the H2A histone degree of acetylation were revealed by treatment of the cells with butyrate (H2A-1, H2A-2) and valproate (H2A-2). The results of the proposed methodology confirmed that inhibition of histone deacetylases caused histone hyperacetylation, responsible for decondensation and reorganization of interphase dynamic chromatin. This method resulted in selective and sensitive method to monitor variations in the acetylation and methylation state of histones after treatment of HT29 with inhibitors, and is therefore suitable for further application in new drug discovery for tumour therapy.


Subject(s)
Chromatography, High Pressure Liquid/methods , Colonic Neoplasms/metabolism , Histones/analysis , Spectrometry, Mass, Electrospray Ionization/methods , Acetylation/drug effects , Butyrates/pharmacology , HT29 Cells , Histone Deacetylase Inhibitors , Histone Deacetylases/metabolism , Histones/chemistry , Histones/metabolism , Humans , Reproducibility of Results , Valproic Acid/pharmacology
11.
J Intern Med ; 258(2): 145-52, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16018791

ABSTRACT

BACKGROUND AND SCOPE: Recent literature has demonstrated that inflammation contributes to all phases of atherosclerosis and brain damage caused by stroke. In acute phase of cerebrovascular diseases biochemical markers of inflammation, such as C-reactive protein (CRP), could represent an indicator of severity of stroke, but few studies have verified this hypothesis, especially in very old patients. The aim of this study was to evaluate the role of CRP on short- and long-term prognosis in 75-year old and over elderly patients with acute ischaemic stroke. MATERIALS AND METHODS: We retrospectively evaluated CRP values (nephelometric method), performed within 12 h from hospital admission, in 196 elderly patients (124 females and 72 males with mean age+/-SD 83.32+/-10.46 years), discharged with diagnosis of acute ischaemic stroke, 68 of them with atherothrombotic large vessel stroke, 38 with lacunar stroke and 90 with cardioembolic stroke. We studied the relationship between CRP values and short-term prognosis [30-day mortality, length of hospitalization (LOS) and physical disability measured by modified Rankin scale and long-term prognosis (12-month mortality and re-hospitalization)]. RESULTS: Mean values of CRP were significantly higher in patients with cardioembolic stroke compared with atherothrombotic large vessel and lacunar stroke, in patients who died in the first 30 days from the acute event compared with survivors. LOS and physical disability score rose with increasing values of CRP for all subtypes of stroke. Higher CRP values were associated with the 12-month re-hospitalization for cerebrovascular events, whereas it did not influence the 12-month cumulative re-hospitalization and 12-month mortality. CONCLUSIONS: Elevation of CRP values at hospital admission could represent a negative prognostic index in elderly patients with ischaemic stroke, in particular, for short-term prognosis.


Subject(s)
C-Reactive Protein/analysis , Stroke/blood , Aged , Aged, 80 and over , Arteriosclerosis/blood , Arteriosclerosis/complications , Arteriosclerosis/mortality , Biomarkers/blood , Disability Evaluation , Female , Humans , Length of Stay , Male , Patient Readmission , Prognosis , Retrospective Studies , Stroke/etiology , Stroke/mortality
12.
Biochem Biophys Res Commun ; 314(1): 138-42, 2004 Jan 30.
Article in English | MEDLINE | ID: mdl-14715257

ABSTRACT

Growing evidence supports the critical role of lipid peroxidation products in the control of cell proliferation. In previous studies we demonstrated the efficient restriction of the proliferation rate in several cell lines resulting from the in vitro treatment with endogenous lipid polar components of cell membranes. Among these, 9-hydroxystearic acid (9-HSA), a primary intermediate of lipid peroxidation, induced a significant arrest in G0/G1 in HT29 colon cancer cells. In response to 9-HSA treatment of HT29 we observed cell growth arrest and increase in p21(WAF1) expression both at the transcriptional and the translational levels. Growth of p21(WAF1)-deleted HCT116 human colon carcinoma cells was not inhibited by 9-HSA. We present evidence that p21(WAF1) is required for 9-HSA mediated growth arrest in human colon carcinoma cells.


Subject(s)
Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , Cyclins/metabolism , Stearic Acids/metabolism , Antineoplastic Agents/metabolism , Antineoplastic Agents/pharmacology , Cell Division/drug effects , Cell Line, Tumor/drug effects , Cell Line, Tumor/metabolism , Cell Line, Tumor/pathology , Cyclin-Dependent Kinase Inhibitor p21 , Humans , Reverse Transcriptase Polymerase Chain Reaction/methods , Stearic Acids/pharmacology , Up-Regulation/drug effects
13.
IEEE Trans Med Imaging ; 21(7): 834-6; author reply 836-7, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12374321

ABSTRACT

In this paper, errors and discrepancies in the subject paper [Cincotti et al., (2002)] are highlighted. A comment, concerning the axial resolution associated to the adopted processing procedure is also reported.


Subject(s)
Image Processing, Computer-Assisted/methods , Signal Processing, Computer-Assisted , Ultrasonography
14.
Biochem Biophys Res Commun ; 293(5): 1502-7, 2002 May 24.
Article in English | MEDLINE | ID: mdl-12054686

ABSTRACT

Several studies point to the existence of an inverse correlation between cellular lipid peroxidation and both cell proliferation and neoplastic transformation. Furthermore, numerous results demonstrate that lipid peroxidation products affect central biochemical pathways and intracellular signalling at physiological concentrations. 4-Hydroxynonenal (HNE) is one of the most active products of lipid peroxidation. This work has focused on the evaluation of HNE nuclear content, so far never directly measured, by electrospray-ionization-mass-spectrometry (ESI/MS) and on the correlation between its concentration and the induced effects after exogenous administration. In a human osteosarcoma cell line (SaOS2), HNE exhibited an early cytotoxic effect characterized by apoptosis, cytostatic and differentiating effects characterized by slow growth, increase in alkaline phosphatase (ALP), and alpha5 integrin subunit content with decrease in tumorigenicity.


Subject(s)
Aldehydes/pharmacology , Cysteine Proteinase Inhibitors/pharmacology , Osteosarcoma/drug therapy , Aldehydes/toxicity , Antigens, CD/metabolism , Apoptosis , Cell Differentiation , Cell Division , Cell Line , Cell Nucleus/metabolism , Chromatin/metabolism , Chromatography, High Pressure Liquid , Cysteine Proteinase Inhibitors/toxicity , Cytoskeleton/metabolism , Humans , Integrin alpha5 , Kinetics , Lipid Peroxidation , Microscopy, Confocal , Osteosarcoma/metabolism , Oxidative Stress , Spectrometry, Mass, Electrospray Ionization , Time Factors , Tumor Cells, Cultured
15.
Rapid Commun Mass Spectrom ; 16(9): 859-64, 2002.
Article in English | MEDLINE | ID: mdl-11948817

ABSTRACT

A sensitive, specific, accurate and reproducible gas chromatography/mass spectrometry method was developed for the assay of 9- and 10-hydroxystearic acids in samples obtained as cell extracts. The preparation of the samples required specific procedures to allow the analysis of both the free and the conjugated hydroxy acids as the corresponding methyl esters. The quantification used propyl-paraben as the internal standard and monitoring of a specific fragment of each isomeric hydroxy acid methyl ester, and allowed quantification of the conjugate and the free fractions of both 9- and 10-hydroxystearic acids. This method is suitable for identification and quantification (LOQ 1.8 and 4.4 ng, respectively) of these important metabolites of lipid peroxidation. In particular the development of an assay for the free 9-hydroxystearic acid methyl ester makes the method a reliable analytical tool for investigations of the role of this metabolite in the mechanisms of tumour cell proliferation.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Lipid Peroxidation , Stearic Acids/analysis , Calibration , Carcinoma/chemistry , Colonic Neoplasms/chemistry , Humans , Reproducibility of Results , Sensitivity and Specificity , Tumor Cells, Cultured
16.
Biochem Biophys Res Commun ; 290(3): 1010-4, 2002 Jan 25.
Article in English | MEDLINE | ID: mdl-11798175

ABSTRACT

This study shows the presence of all three nitric oxide synthases (NOSs) and NOS activity in H9c2 cells cultured under non-stimulated conditions. By using the 4,5 diaminofluoresceindiacetate (DAF-2DA) fluorimetric nitric oxide (NO(*)) detection system we observed NO(*) production in H9c2 cells. As revealed by confocal microscopy, NO(*) fluorescence colocalizes in mitochondria labeled with Mito-Tracker Red CM-H(2)Xros. Upon stimulation with acetylcholine (Ach), which increased NOS activity by 75%, the colocalization coefficient C(green) value, calculated as Pearson's correlation, increased from 0.07 to 0.10, demonstrating an augmented presence of NO(*) in mitochondria. Conversely, the presence of NO(*) in mitochondria decreased following cells pretreatment with l-MonoMethylArginine (L-NMMA), a competitive inhibitor of NOS activity, as indicated by the reduction of the C(green) value to 0.02. This work confirms that the presence of NO(*) in mitochondria can be modulated in response to different fluxes of NO(*).


Subject(s)
Mitochondria/chemistry , Nitric Oxide/analysis , Acetylcholine/pharmacology , Animals , Cell Line , Cell Line, Transformed , Fluorescein/chemistry , Fluorometry , Indicators and Reagents/chemistry , Microscopy, Confocal , Mitochondria/enzymology , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/metabolism , Protein Isoforms/metabolism , Rats , Rats, Wistar , omega-N-Methylarginine/pharmacology
17.
Biochemistry ; 40(27): 8030-42, 2001 Jul 10.
Article in English | MEDLINE | ID: mdl-11434772

ABSTRACT

Site-directed mutagenesis, gel filtration, and fluorescence spectroscopy approaches were used to study the molecular hinge mechanism involved in the beta-strand-exchanged dimer formation of the cyclin-dependent protein kinase regulatory subunit p13(suc1) from Schizosaccharomyces pombe. Single and double mutants of residues Pro-90 and Pro-92 (P90V, P92V, and P90V/P92V) were prepared and assayed. Substitution of Pro-90 prevented dimer formation by arm exchange. However, single point mutations did not affect the two-state unfolding transition of wild-type p13(suc1) at equilibrium (i.e., wild type, DeltaG degrees (0,un) = 7.38 +/- 0.35 kcal mol(-1), vs P90V, DeltaG degrees (0,un) = 6.71 +/- 0.18 kcal mol(-1)). On the contrary, the double mutant unfolded with a complex transition, and the reaction was best described by a three-state model (N <==> I <==> U). Resolution of the state-dependent (native vs denatured) intrinsic fluorescence decay amplitudes of p13(suc1) showed that with P90V/P92V these parameters were affected at [GuHCl] significantly less than with wild-type and single mutant proteins. Moreover, with the latter products, fluorescence quenching measurements at 1 M GuHCl revealed linear Stern-Volmer plots with quenching constants typical of tryptophan residues located in a native environment (1.6 M(-1) < K(SV) < 2.3 M(-1)). Dissimilarly, with P90V/P92V a significant deviation from linearity of the Stern-Volmer plot was obtained. Nonlinear least-squares analysis of these data resolved the significant contribution of highly solvent-accessible emitting species (K(SV) = 26 M(-1)) consistent with large exposure of the tryptophan residues. These results are compatible with the existence of an intermediate unfolding state of the double mutation product. Thus, while single residue substitution studies give support to the primary role of Pro-90 in the p13(suc1) dimer formation by domain swapping, double residue substitution studies indicate the important role of the conserved repeat, Pro-x-Pro, for the proper beta-strand spatial organization and stability.


Subject(s)
Cell Cycle Proteins , Cyclin-Dependent Kinases/chemistry , Fungal Proteins/chemistry , Mutagenesis, Site-Directed , Proline/chemistry , Schizosaccharomyces pombe Proteins , Schizosaccharomyces/enzymology , Cyclin-Dependent Kinases/genetics , Cyclin-Dependent Kinases/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Guanidine , Peptide Fragments/chemistry , Peptide Fragments/genetics , Peptide Fragments/metabolism , Proline/genetics , Protein Denaturation/genetics , Protein Folding , Protein Structure, Secondary/genetics , Protein Structure, Tertiary/genetics , Schizosaccharomyces/genetics , Spectrometry, Fluorescence , Thermodynamics
18.
J Exp Clin Cancer Res ; 20(1): 135-43, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11370820

ABSTRACT

The aim of this work is the in vitro study of the late effects of single proton irradiation on HTB63 human melanoma cell growth, cell cycle and cell death. The experimental conditions were focused on analyzing the effects of irradiation on the periphery of tumour that can be, in clinical practice, close to critical organs. Confluent cell monolayers were irradiated with single doses ranging from 1 - 20 Gy, using proton beams having an energy of 22.6 MeV at the target. Antiproliferative effect of protons, cell cycle analysis and initiation of cell death, were followed 48 hours after irradiation. The inhibition of melanoma cell growth was observed, especially after single application of 12 and 16 Gy. Cell cycle analysis and cell viability have shown the G2/M and G1/G0 arrest of irradiated cells correlating with the increase of the applied dose. The flow cytometric analysis has shown presence of apoptotic nuclei. These data demonstrate that irradiation with protons, under the chosen experimental conditions, have significant effects on melanoma cell growth inhibition being dose dependent, G2/M cell cycle arrest and appearance of apoptotic nuclei, even 48 hours after irradiation. The results obtained may help the understanding of the relationship between cell proliferation, death and cell cycle regulation of melanomas after proton irradiation.


Subject(s)
Apoptosis/radiation effects , Cell Cycle/radiation effects , Cell Division/radiation effects , Protons , Cell Survival/radiation effects , Dose-Response Relationship, Radiation , G1 Phase/radiation effects , G2 Phase/radiation effects , Genes, p53/radiation effects , Humans , Melanoma , Mitosis/radiation effects , Resting Phase, Cell Cycle/radiation effects , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured , Tumor Suppressor Protein p53/radiation effects
20.
J Gerontol A Biol Sci Med Sci ; 55(12): M761-4, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11129400

ABSTRACT

BACKGROUND: Arterial blood gas analysis (BGA) remains a first-step diagnostic approach in patients with suspected pulmonary embolism (PE). The aim of this study was to evaluate BGA parameters in elderly patients with suspected pulmonary embolism for diagnosis and 14-day prognosis. METHODS: We performed a retrospective cohort observational study of 6 years (1994-1999) in a 60-bed acute geriatric ward of University Hospital in Siena, Italy. Room air arterial oxygen partial pressure (pO2), arterial carbon dioxide partial pressure (pCO2), pH, arterial oxyhemoglobin saturation (SO2), and alveolar-arterial oxygen gradient [D(A-a)O2] were performed on hospital admission of 75 patients with confirmed PE (CPE) and were compared with data from 43 patients with unconfirmed PE (UCPE). The same parameters of 54 CPE surviving patients were compared with 21 CPE nonsurviving patients. RESULTS: Significantly lower PO2 and SO2, and higher DA-aO2 were found in CPE patients. Respiratory alkalosis was found in one third of the patients in both groups (no significant difference). In the CPE group, there was a significantly lower SO2 in nonsurviving patients, without significant differences for the other parameters. Metabolic acidosis was significantly more frequent in nonsurviving patients. CONCLUSION: More severe hypoxemia, oxyhemoglobin hyposaturation, and higher D(A-a)O2 are associated with the diagnosis of PE in elderly patients. Respiratory alkalosis is less frequent than in younger patients, and metabolic disorders are negative prognostic indicators.


Subject(s)
Carbon Dioxide/blood , Oxygen/metabolism , Pulmonary Alveoli/metabolism , Pulmonary Embolism/diagnosis , Pulmonary Embolism/metabolism , Aged , Aged, 80 and over , Arteries , Cohort Studies , Female , Humans , Male , Oxygen/blood , Oxyhemoglobins/analysis , Partial Pressure , Prognosis , Pulmonary Embolism/blood , Pulmonary Embolism/mortality , Retrospective Studies
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