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1.
J Viral Hepat ; 25(8): 911-919, 2018 08.
Article in English | MEDLINE | ID: mdl-29577518

ABSTRACT

The interplay between hepatitis B (HBV) and delta (HDV) viruses is complex and not always characterized during chronic HDV infection. We assessed the clinical usefulness of new quantitative assays for HBV and HDV serum markers in a retrospective cross-sectional study. Sera obtained from 122 HDV genotype 1 and HBV genotype D coinfected, anti-HIV-negative patients (71 males; median age 49.8 [21.7-66.9] years), recruited consecutively in two geographical areas (Italy 69 patients, Romania 53 patients) with different HBV and HDV epidemiology, were tested for HBsAg, HBV-DNA, HBcrAg, total anti-HBc, HDV-RNA, IgM and total anti-HDV using quantitative assays. Cirrhosis, which showed comparable prevalence in the two cohorts, was diagnosed in 97 of 122 (79.5%) patients. At multivariate analysis, cirrhosis was associated with lower total anti-HBc/IgM anti-HDV ratio (OR 0.990, 95% CI 0.981-0.999, P = .038), whereas disease activity was associated with higher total anti-HDV (OR 10.105, 95% CI 1.671-61.107, P = .012) and HDV-RNA levels (OR 2.366, 95% CI 1.456-3.844, P = .001). HDV-RNA serum levels showed a positive correlation with HBV-DNA (ρ = 0.276, P = .005), HBsAg (ρ = 0.404, P < .001) and HBcrAg (ρ = 0.332, P < .001). The combined quantitative profiling of HBV and HDV serum markers identifies specific patterns associated with activity and stage of chronic hepatitis D (CHD). HDV pathogenicity depends on the underlying active HBV infection in spite of the inhibition of its replication. HDV-RNA, IgM anti-HDV, total anti-HDV, total anti-HBc, HBsAg and HBcrAg serum levels qualify for prospective studies to predict progressive CHD and identify candidates to antiviral therapy.


Subject(s)
Biomarkers/blood , Coinfection/pathology , Hepatitis B, Chronic/complications , Hepatitis B, Chronic/pathology , Hepatitis D, Chronic/pathology , Adult , Aged , Cross-Sectional Studies , DNA, Viral/blood , Female , Genotype , Hepatitis Antibodies/blood , Hepatitis B Core Antigens/blood , Hepatitis B Surface Antigens/blood , Humans , Immunoglobulin M/blood , Italy , Male , Middle Aged , RNA, Viral/blood , Retrospective Studies , Romania , Young Adult
2.
G Ital Med Lav Ergon ; 34(3 Suppl): 361-4, 2012.
Article in Italian | MEDLINE | ID: mdl-23405662

ABSTRACT

Even though Obstructive Sleep Apnea Syndrome (OSAS) is one of the main causes of daytime sleepiness with high subsequent risk for causing vehicle accidents, its evaluation is not usually included among the criteria used for the certification of job fitness among professional drivers. In order to assess the feasibility of a screening method that allows the occupational physician to identify the subjects at risk for OSAS which should undergo second level tests (cardiorespiratory monitoring), we recorded and subsequently processed appropriate subjective and objective indicators among 455 professional drivers employed in private transportation companies. Only 17 subjects (47%) out of 36 tested positive underwent cardiorespiratory monitoring (due to technical and organizational difficulties and to the poor compliance of workers). OSAS was confirmed in 15 subjects out of 17 showing an excellent positive predictive value of the screening. Risk management for OSAS is currently unavoidable yet not formally provided by law. Our results show the possibility of completing the health surveillance program with feasible and valuable screening tests. Difficulties (hardly compliant with a timely certification of the job fitness) arise instead as far as second level confirmatory procedures are involved.


Subject(s)
Automobile Driving , Medical History Taking , Occupational Diseases/diagnosis , Population Surveillance , Sleep Apnea, Obstructive/diagnosis , Transportation , Adult , Aged , Cohort Studies , Humans , Middle Aged , Private Sector , Time Factors , Young Adult
3.
Environ Sci Technol ; 46(2): 1010-8, 2012 Jan 17.
Article in English | MEDLINE | ID: mdl-22136062

ABSTRACT

The treatment of a pharmaceutical wastewater resulting from the production of an antibacterial drug (nalidixic acid) was investigated employing a membrane bioreactor (MBR) integrated with either ozonation or UV/H(2)O(2) process. This was achieved by placing chemical oxidation in the recirculation stream of the MBR. A conventional configuration with chemical oxidation as polishing for the MBR effluent was also tested as a reference. The synergistic effect of MBR when integrated with chemical oxidation was assessed by monitoring (i) the main wastewater characteristics, (ii) the concentration of nalidixic acid, (iii) the 48 organics identified in the raw wastewater and (iv) the 55 degradation products identified during wastewater treatment. Results showed that MBR integration with ozonation or UV/H(2)O(2) did not cause relevant drawbacks to both biological and filtration processes, with COD removal rates in the range 85-95%. Nalidixic acid passed undegraded through the MBR and was completely removed in the chemical oxidation step. Although the polishing configuration appeared to give better performances than the integrated system in removing 15 out of 48 secondary organics while similar removals were obtained for 19 other compounds. The benefit of the integrated system was however evident for the removal of the degradation products. Indeed, the integrated system allowed higher removals for 34 out of 55 degradation products while for only 4 compounds the polishing configuration gave better performance. Overall, results showed the effectiveness of the integrated treatment with both ozone and UV/H(2)O(2).


Subject(s)
Bioreactors , Hydrogen Peroxide , Industrial Waste/analysis , Organic Chemicals/chemistry , Ultraviolet Rays , Waste Disposal, Fluid/methods , Membranes, Artificial , Nalidixic Acid/chemistry , Water Pollutants, Chemical/chemistry , Water Purification
4.
Eur Respir J ; 28(1): 174-81, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16816347

ABSTRACT

After lung surgery, some patients complain of unexplained increased dyspnoea associated with hypoxaemia. This clinical presentation may be due to an interatrial right-to-left shunt despite normal right heart pressure. Some of these patients show postural dependency of hypoxaemia, whereas others do not. In this article, the pathogenesis and mechanisms involved in this post-surgical complication are discussed, and the techniques used for confirmation and localisation of shunt are reported. An invasive technique, such as right heart catheterisation with angiography, was often used in the past as the diagnostic procedure for the visualisation of interatrial shunt. As to noninvasive techniques, a perfusion lung scan may be used as the first approach as it may detect the effect of the right-to-left shunt by visualising an extrapulmonary distribution of the radioactive tracer. The 100% oxygen breathing test could also be used to quantify the amount of right-to-left shunt. Particular emphasis is given to newer imaging modalities, such as transoesophageal echocardiography, which is minimally invasive but highly sensitive in clearly visualising the atrial septum anatomy. Finally, the approach to closure of the foramen ovale or atrial septal defect is discussed. Open thoracotomy was the traditional approach in the past. Percutaneous closure has now become the most used and effective technique for the repair of the interatrial anatomical malformation.


Subject(s)
Dyspnea/diagnosis , Hypoxia/diagnosis , Lung/surgery , Pulmonary Surgical Procedures/adverse effects , Aged , Angiography , Dyspnea/etiology , Female , Follow-Up Studies , Heart Defects, Congenital/pathology , Heart Septal Defects, Atrial/pathology , Humans , Hypoxia/etiology , Male , Middle Aged , Postoperative Complications , Prevalence , Pulmonary Gas Exchange
5.
Acta Haematol ; 108(3): 132-8, 2002.
Article in English | MEDLINE | ID: mdl-12373084

ABSTRACT

Nine carriers of beta-abnormal haemoglobins with increased oxygen affinity (Hb X) were examined. Their oxygen dissociation curves from whole blood were more or less left-shifted, with six of nine also characterized by biphasism. This refers to an 'inflection point' usually positioned at about 50-60% of Hb O(2) saturation, commonly believed to be a limit between oxygenation of the normal and abnormal components. In effect, the inflection does not always correspond to the Hb X level, which sometimes is much lower than 50% of the total Hb. Moreover, the upper half segment of the dissociation curve could not only be an expression of Hb A oxygenation, since it is always left-shifted. However, a high Hb A level is commonly believed to be the main compensatory factor of these subjects, but many indications suggest that often they have at least three, and not only two, main haemoglobin species: Hb A, Hb X plus hybrids of the type alpha(2)beta(A)beta(X). These would oxygenate after Hb X, but before Hb A. Finally, the interaction of 2,3-diphosphoglycerate with Hb X and/or hybrid tetramers must be altered, and the releasing of oxygen from both is more or less reduced. Unfortunately, it is difficult to demonstrate the presence of hybrids directly, i.e. with amino acid analysis of the abnormal beta-globin.


Subject(s)
Hemoglobins/analysis , Hemoglobins/chemistry , Oxygen/chemistry , Chromatography, High Pressure Liquid , Humans , Oxidation-Reduction , Protein Binding
6.
Am J Med ; 110(7): 528-35, 2001 May.
Article in English | MEDLINE | ID: mdl-11343666

ABSTRACT

PURPOSE: Echocardiography is advocated by some as a useful diagnostic test for patients with suspected pulmonary embolism (PE), but its diagnostic accuracy is unknown. The present study was undertaken to determine prospectively the sensitivity and specificity of transthoracic echocardiography in the diagnosis of PE. SUBJECTS AND METHODS: We examined 110 consecutive patients with suspected PE. The study protocol included assessment of clinical probability, echocardiography, and perfusion lung scanning. Pulmonary angiography was performed in all patients with abnormal scans. As echocardiographic criteria to diagnose acute PE, we used the presence of any two of the following: right ventricular (RV) hypokinesis, RV end-diastolic diameter >27 mm (without RV wall hypertrophy), or tricuspid regurgitation velocity >2.7 m/sec. Clinical estimates of PE served as pretest probabilities in calculating, after echocardiography, the posttest probabilities of PE. RESULTS: Pulmonary angiography confirmed PE in 43 (39%) of 110 patients. Echocardiographic diagnostic criteria for PE yielded a sensitivity of 56% and a specificity of 90%. For pretest probabilities of 10%, 50%, and 90%, the posttest probabilities of PE conditioned by a positive echocardiogram were 38%, 85%, and 98%, respectively. The posttest probabilities of PE conditioned by a negative echocardiogram were 5%, 33%, and 81%, respectively. CONCLUSIONS: In unselected patients with suspected PE, transthoracic echocardiography fails to identify some 50% of patients with angiographically proven PE. Although echocardiographic findings of RV strain, paired with a high clinical likelihood, support a diagnosis of PE, the transthoracic echocardiography has to have a better sensitivity to be used as a screening test to rule out PE.


Subject(s)
Pulmonary Embolism/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Echocardiography, Doppler , Female , Humans , Male , Middle Aged , Probability , Prospective Studies , Reference Standards , Risk Factors , Sensitivity and Specificity
7.
Ann Chim ; 91(9-10): 587-94, 2001.
Article in English | MEDLINE | ID: mdl-11770158

ABSTRACT

This is the first of two papers each dealing with a specific technological option for replacing the Fenton's reagent with simpler processes for treating industrial wastewater. In particular, the paper reports the results of an investigation aimed to check, at lab scale, the effectiveness of a chemical process (i.e., alkalinisation with or without post-ozonation) for treating tannery wastewater whose residual COD, measured after conventional biological treatment, result still higher than the Italian COD Maximum Allowable Concentration (MAC) value (i.e., 160 mgO2/L). The results have demonstrated that when the value of residual COD lies in the range 200 divided by 250 mgO2/L, a simple alkalinisation with NaOH, up to pH 12.5, allows to reach the MAC value with an alkali consumption equivalent to the acid consumption required by the Fenton treatment and with a chemical sludge production significantly lower, i.e. approximately 0.7 kg(dry)/m3 instead of approximately 1.5 kg(dry)/m3. Conversely, when the value of the residual COD lies in a higher range (i.e. 300 divided by 350 mgO2/L), in order to reach the COD MAC value, alkalinisation (from pH 8 to pH 12.5) must be followed by an ozonation post-treatment. From the chemical stand point, the paper clearly demonstrates that analyzing only simple "gross parameters" (i.e., TSS, TOC, COD, BOD5 and EC20) it is possible to get useful information about the chemical properties of the organic pollutants occurring in tannery wastewater.


Subject(s)
Industrial Waste , Oxidants, Photochemical/chemistry , Ozone/chemistry , Waste Disposal, Fluid/methods , Water Purification/methods , Hydrogen Peroxide , Hydrogen-Ion Concentration , Iron , Organic Chemicals , Oxidation-Reduction , Oxygen/chemistry
8.
Phys Rev Lett ; 85(22): 4682-6, 2000 Nov 27.
Article in English | MEDLINE | ID: mdl-11082626

ABSTRACT

The cross section for straight phi meson photoproduction on the proton has been measured for the first time up to a four-momentum transfer -t = 4 GeV2, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. At low four-momentum transfer, the differential cross section is well described by Pomeron exchange. At large four-momentum transfer, above -t = 1.8 GeV2, the data support a model where the Pomeron is resolved into its simplest component, two gluons, which may couple to any quark in the proton and in the straight phi.

10.
Am J Respir Crit Care Med ; 159(3): 864-71, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10051264

ABSTRACT

To provide clinical diagnostic criteria for pulmonary embolism (PE), we evaluated 750 consecutive patients with suspected PE who were enrolled in the Prospective Investigative Study of Acute Pulmonary Embolism Diagnosis (PISA-PED). Prior to perfusion lung scanning, patients were examined independently by six pulmonologists according to a standardized diagnostic protocol. Study design required pulmonary angiography in all patients with abnormal scans. Patients are reported as two distinct groups: a first group of 500, whose data were analyzed to derive a clinical diagnostic algorithm for PE, and a second group of 250 in whom the diagnostic algorithm was validated. PE was diagnosed by angiography in 202 (40%) of the 500 patients in the first group. A diagnostic algorithm was developed that includes the identification of three symptoms (sudden onset dyspnea, chest pain, and fainting) and their association with one or more of the following abnormalities: electrocardiographic signs of right ventricular overload, radiographic signs of oligemia, amputation of hilar artery, and pulmonary consolidations compatible with infarction. The above three symptoms (singly or in some combination) were associated with at least one of the above electrocardiographic and radiographic abnormalities in 164 (81%) of 202 patients with confirmed PE and in only 22 (7%) of 298 patients without PE. The rate of correct clinical classification was 88% (440/500). In the validation group of 250 patients the prevalence of PE was 42% (104/250). In this group, the sensitivity and specificity of the clinical diagnostic algorithm for PE were 84% (95% CI: 77 to 91%) and 95% (95% CI: 91 to 99%), respectively. The rate of correct clinical classification was 90% (225/250). Combining clinical estimates of PE, derived from the diagnostic algorithm, with independent interpretation of perfusion lung scans helps restrict the need for angiography to a minority of patients with suspected PE.


Subject(s)
Pulmonary Embolism/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Algorithms , Angiography , Electrocardiography , Female , Humans , Lung/blood supply , Lung/diagnostic imaging , Male , Middle Aged , Prospective Studies , Pulmonary Embolism/diagnostic imaging , Radionuclide Imaging , Risk Factors , Sensitivity and Specificity
11.
Crit Care ; 3(4): 111-116, 1999.
Article in English | MEDLINE | ID: mdl-11056733

ABSTRACT

OBJECTIVE: To assess the value of parameters derived from arterial blood gas tests in the diagnosis of pulmonary embolism. METHOD: We measured alveolar-arterial partial pressure of oxygen [P(A-a)O2] gradient, PaO2 and arterial partial pressure of carbon diaxide (PaCO2) in 773 consecutive patients with suspected pulmonary embolism who were enrolled in the Prospective Investigative Study of Acute Pulmonary Embolism. DIAGNOSIS: The study design required pulmonary angiography in all patients with abnormal perfusion scans. RESULTS: Of 773 scans, 270 were classified as normal/near-normal and 503 as abnormal. Pulmonary embolism was diagnosed by pulmonary angiography in 312 of 503 patients with abnormal scans. Of 312 patients with pulmonary embolism, 12, 14 and 35% had normal P(A-a)O2, PaO2 and PaCO2, respectively. Of 191 patients with abnormal scans and negative angiograms, 11, 13 and 55% had normal P(A-a)O2, PaO2 and PaCO2, respectively. The proportions of patients with normal/near-normal scans who had normal P(A-a)O2, PaO2 and PaCO2 were 20, 25 and 37%, respectively. No differences were observed in the mean values of arterial blood gas data between patients with pulmonary embolism and those who had abnormal scans and negative angiograms. Among the 773 patients with suspected pulmonary embolism, 364 (47%) had prior cardiopulmonary disease. Pulmonary embolism was diagnosed in 151 (41%) of 364 patients with prior cardiopulmonary disease, and in 161 (39%) of 409 patients without prior cardiopulmonary disease. Among patients with pulmonary embolism, there was no difference in arterial blood gas data between patients with and those without prior CPD. CONCLUSION: These data indicate that arterial blood gas tests are of limited value in the diagnostic work-up of pulmonary embolism if they are not interpreted in conjunction with clinical and other laboratory tests.

12.
Panminerva Med ; 40(3): 250-3, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9785927

ABSTRACT

An electrophoretically slow-moving hemoglobin, with abnormal beta chains, has been found in a young woman and in three members of her family. This variant amounted to 41% of the total Hb, and did not cause important clinical manifestations, although characterized by decreased oxygen affinity. Structural and aminoacid analyses revealed the mutation of Hb-Agenogi: 90 (F6) Glu-->Lys, a rare variant so far detected in unrelated racial and ethnic groups. This is the first affected family of ascertained Piedmontese ancestry.


Subject(s)
Hemoglobins, Abnormal/genetics , Adult , Female , Glutamic Acid/genetics , Hemoglobins, Abnormal/analysis , Humans , Lysine/genetics , Mutation
13.
Int J Cardiol ; 65 Suppl 1: S83-6, 1998 May 29.
Article in English | MEDLINE | ID: mdl-9706834

ABSTRACT

Pulmonary embolism (PE) remains a challenging diagnostic problem because it mimics other cardiopulmonary disorders. Pulmonary angiography is still the reference standard for diagnosing PE but it is costly, invasive and not readily available. Non-invasive diagnostic strategies have therefore been developed to forego pulmonary angiography in patients suspected of having PE. Ventilation/perfusion lung scanning is, at present, the most widely used non-invasive diagnostic test for PE. A high probability ventilation/perfusion scan (segmental or greater perfusion defects with normal ventilation) warrants the institution of anticoagulant therapy especially when paired with high clinical suspicion of PE. Yet, only a minority of patients with confirmed PE have high probability ventilation/perfusion scans. Ventilation/perfusion abnormalities other than those of the high probability scan should be regarded as non-diagnostic. Under these circumstances, documentation of deep vein thrombosis by non-invasive leg testing warrants anticoagulation without the need for angiography. However, a single negative venous study result does not permit to rule out PE in patients with non-diagnostic ventilation/perfusion scans. Results of a recent prospective study indicate that accurate diagnosis or exclusion of PE is possible with perfusion lung scanning alone (without ventilation imaging). Combining perfusion lung scanning with clinical assessment helps to restrict the need for angiography to a minority of patients with suspected PE.


Subject(s)
Pulmonary Embolism/diagnostic imaging , Clinical Trials as Topic , Humans , Perfusion , Predictive Value of Tests , Pulmonary Circulation , Pulmonary Ventilation , Radionuclide Imaging
14.
Minerva Med ; 89(4): 131-5, 1998 Apr.
Article in Italian | MEDLINE | ID: mdl-9676178

ABSTRACT

The oxygen carrying capacity of dilute solutions of hemoglobin from normal human adults was examined, by using the above indicated Oximeter. The results show that, if the pO2s are compared with those drawn from the Oximeter-539 WTW (a simpler instrument) carrying the same oxygen electrode, there is a good correspondence between the data drawn from both the instruments. The advantage of the former is that pO2s are measure in mBr, whereas the latter measures the oxygen of the aqueous solutions in mg/l; then mg must be converted into Torr pO2. Since both instruments are usually employed in the oxygen measurement of waste waters of earth, another conclusion is that their sensitivity also allows the use in the bio-medical (and zoological) field. In fact, the data obtained agree with those of recent literature on the subject, which are mainly drawn from automated and sophisticated apparatuses specifically built at this purpose.


Subject(s)
Hemoglobins/analysis , Oximetry/instrumentation , Adult , Electrodes , Humans , Hydrogen-Ion Concentration , Oximetry/methods , Oxygen/blood , Oxyhemoglobins/metabolism , Solutions
15.
Panminerva Med ; 39(3): 169-73, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9360416

ABSTRACT

The whole blood oxygen affinity of a Negro carrier of SC disease was found to be characterized by some right-shifted p50 and clearly increased Bohr effect, whereas the isolated and purified Hb-S and Hb-C exhibited slight deficiencies mainly of the Bohr effect. The right-shifted p50 from whole blood can be easily explained by the mild anemia with a parallel increase of 2,3-diphosphoglycerate (DPG), whereas the functional discrepancies between whole blood function and that of the purified Hb-S and C could be due, at least in part, to the presence in vivo of consistent amounts of hybrid Hb tetramers of the type alpha alpha beta S beta C. Unfortunately, the mechanism promoting the formation (or dissolution) of hybrids are fundamentally unknown; so, either their presence and functional properties are very difficult to be explored.


Subject(s)
Hemoglobin C/metabolism , Hemoglobin, Sickle/metabolism , Oxygen/blood , Adult , Female , Hemoglobin SC Disease/blood , Humans
16.
Hemoglobin ; 21(4): 345-61, 1997 Jul.
Article in English | MEDLINE | ID: mdl-9255613

ABSTRACT

Hb Gàmbara is a new hemoglobin variant with abnormal beta chains that has been found in three out of four members of a family of Lombardy origin (Gàmbara, Brescia, Northern Italy). The affected subjects led a normal life, but they had modest erythrocytosis and mild (compensated) hemolysis with slight splenomegaly. Their abnormal hemoglobin was about 52% of the total hemoglobin, and was shown to be stable by the isopropanol test. Whole blood P50 of the proband was 19.3 Torr, Bohr effect was decreased (-0.25), as well as the molar ratio between the 2,3-diphosphoglycerate level and total hemoglobin of erythrocytes (0.68). The purified abnormal hemoglobin was characterized by an altered oxygen affinity, low n-factor, chloride, and 2,3-diphosphoglycerate effects. The Bohr effect was about 40% of the normal control. The abnormal hemoglobin moved faster than Hb A at alkaline electrophoresis, and split into two fractions, probably due to the formation of hybrid tetramers (alpha 2 beta A beta X). The reversed phase high performance liquid chromatogram from the tryptic digest of the aminoethylated abnormal beta chain subunits indicated the presence of an extra peptide, beta T-9, 10, replacing the individual peptides beta T-9 and beta T-10. Finally, the proband's DNA, drawn from a suitable segment of the beta structural gene (exon 2), revealed a nucleotide sequence carrying the heterozygous mutation AAG-->GAG at codon 82. This led to a Lys-->Glu substitution at position 82(EF6) of the beta chain.


Subject(s)
Hemoglobins, Abnormal/genetics , Point Mutation , Polycythemia/genetics , Electrophoresis , Erythrocytes/pathology , Glutamine , Hemoglobins, Abnormal/analysis , Humans , Lysine , Male , Middle Aged , Polycythemia/pathology
17.
Panminerva Med ; 39(2): 153-7, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9230628

ABSTRACT

Dissociation curves for oxygen of dilute samples of human adult Hb-A were evaluated on this occasion, by using the Oximeter-539 WTW with its sensor, and a suitable spectrophotometer. At this purpose, Hb samples were desaturated in oxygen upon given experimental conditions, by bubbling pure nitrogen in them, and their re-oxigenation in air was followed, step by step, by multiple oximetries. In addition, all the spectrophotometric measurements of the saturation of Hb-O2%, corresponding to each individual oximetry, were carried out parallely but separately. Dilution of Hb-A was maintained at 0.1 mM in heme. The p50 at pH 7.3 was 4.435 +/- 0.299 Torr, with the n-value of 2.7 +/- 0.2; Bohr effect was -0.55 +/- 0.08, within a pH range between 6.8, 7.3 and 7.8, whereas chloride and DPG effects at pH 7.3 (the most useful value) were 0.42 +/- 0.44 and 0.453 +/- 0.0187 respectively. In conclusion, these results are similar to those obtained with automated procedures, upon comparable experimental conditions, but do not require expensive and sophisticated instruments. Such a technique could be very useful in the hemoglobinopathies, which are common in Italy, and it could be easily adapted to perform comparative studies on animal hemoglobins not far from human species.


Subject(s)
Hemoglobin A/analysis , Oximetry/methods , Adult , Humans , Hydrogen-Ion Concentration , Solutions
18.
Am J Respir Crit Care Med ; 154(5): 1387-93, 1996 Nov.
Article in English | MEDLINE | ID: mdl-8912753

ABSTRACT

To assess the value of perfusion lung scan in the diagnosis of pulmonary embolism, we prospectively evaluated 890 consecutive patients with suspected pulmonary embolism. Prior to lung scanning, each patient was assigned a clinical probability of pulmonary embolism (very likely, possible, unlikely). Perfusion scans were independently classified as follows: (1) normal, (2) near-normal, (3) abnormal compatible with pulmonary embolism (PE+: single or multiple wedge-shaped perfusion defects), or (4) abnormal not compatible with pulmonary embolism (PE-: perfusion defects other than wedge-shaped). The study design required pulmonary angiography and clinical and scintigraphic follow-up in all patients with abnormal scans. Of 890 scans, 220 were classified as normal/or near-normal and 670 as abnormal. A definitive diagnosis was established in 563 (84%) patients with abnormal scans. The overall prevalence of pulmonary embolism was 39%. Most patients with angiographically proven pulmonary embolism had PE+ scans (sensitivity: 92%). Conversely, most patients without emboli on angiography had PE- scans (specificity: 87%). A PE+ scan associated with a very likely or possible clinical presentation of pulmonary embolism had positive predictive values of 99 and 92%, respectively. A PE- scan paired with an unlikely clinical presentation had a negative predictive value of 97%. Clinical assessment combined with perfusion-scan evaluation established or excluded pulmonary embolism in the majority of patients with abnormal scans. Our data indicate that accurate diagnosis of pulmonary embolism is possible by perfusion scanning alone, without ventilation imaging. Combining perfusion scanning with clinical assessment helps to restrict the need for angiography to a minority of patients with suspected pulmonary embolism.


Subject(s)
Pulmonary Embolism/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Bayes Theorem , Female , Humans , Male , Middle Aged , Perfusion , Prospective Studies , Pulmonary Embolism/classification , Radionuclide Angiography , Sensitivity and Specificity
19.
Boll Soc Ital Biol Sper ; 72(9-10): 231-8, 1996.
Article in English | MEDLINE | ID: mdl-9425719

ABSTRACT

A mixture of NADH, cytochrome-C-reductase and methylene blue was employed to antagonize ferri(met)-Hb formation during oximetries of dilute samples of human Hb-A. Its efficacy is clear at any pH between 6.8, 7.3 and 7.8, in the presence of 100 mM NaCl. In these cases, ferri(met)-Hb decreases of about 2/3, compared with the enzyme-free controls, and p50 increases. On the contrary, when samples are examined at pH 7.3 with 600 mM NaCl and/or 100 mM NaCl plus 1 mM DPG, ferri(met)-Hb of the samples containing the enzymes also decreases, but not more than 1/2 of its initial value, whereas also p50 decreases. Finally, Bohr effect is lower in the samples containing the enzymes. In conclusion, the enzymatic mixture is very useful, but not easy to be handled; so, some observations for its correct use are required.


Subject(s)
Electron Transport Complex IV/metabolism , Hemoglobin A/metabolism , Methemoglobin/metabolism , NAD/metabolism , Oximetry , Adult , Humans , Solutions
20.
Boll Soc Ital Biol Sper ; 72(7-8): 195-202, 1996.
Article in English | MEDLINE | ID: mdl-9009058

ABSTRACT

Functional parameters of diluted Hb-A have been determined before and after addition of catalase and disodium-EDTA to the samples. There are no important differences between the results drawn from catalase added samples and catalase free ones, except for the fact the met-Hb level at pH 7.8 is significantly lower in the samples containing catalase. On the contrary, catalase is almost ineffective against met-Hb at pH 6.8, whereas its activity at pH 7.3 is rather modest. Another limitation is that catalase remains active against met-Hb for not more than 15-20 minutes after addition to the sample, which is just the time necessary for one complete (manual) oximetry.


Subject(s)
Catalase , Hemoglobin A/analysis , Oximetry/methods , Humans , Hydrogen-Ion Concentration , Spectrophotometry
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