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Biomedical subjects

A Orlandini

Publications and source records attributed to A Orlandini.

At least 37 records · Page 2Linked to original sources
PubMed1991

Two-dimensional echocardiography in myocardial amyloidosis.

Two-dimensional echocardiography is the best means of identifying early cardiac amyloid infiltration and gauging its subsequent progression. The early asymptomatic phase is characterized on echocardiography by a mild-to-moderate increase in left ventricular and/or right ventricular wall thicknesses. The distinctive combination of low electrocardiography voltage and increase in left ventricular mass on the echocardiogram, both compatible with substantial amyloid infiltration, is valuable in diagnosis and appears to indicate the severity of the disease. Other ancillary but common findings are left atrial dilatation, a small pericardial effusion, thickening of cardiac valves, papillary muscles, and interatrial septum. Finally, there is a peculiar texture of myocardial walls, with highly refractile areas that are typical, although not specific, of myocardial amyloidosis and can also be quantitatively described by digital image analysis techniques. The echocardiographic appearance of amyloidosis can closely mimic several other diseases. Asymmetric hypertrophy of the septum due to amyloid deposition may occur, simulating hypertrophic cardiomyopathy. The granular sparkling of myocardial walls is also found in myocarditis with severe fibrosis, and it is quite common in hypertrophic cardiomyopathy, as well as in other infiltrative diseases of the myocardium. It is not uncommon that the echocardiographic examination represents a turning point in the work-up of the patient, briskly orienting the clinician towards the correct diagnostic pathway. However, the likelihood of the cardiologist-echocardiographer to successfully and prospectively identify myocardial amyloidosis is substantially higher if all the clinical and electrocardiographic information is reviewed at the time of the echocardiographic examination.

Amyloidosis↗
PubMed1991

Inhibition of dipyridamole-induced ischemia by antianginal therapy in humans. Correlation with exercise electrocardiography.

BACKGROUND: Dipyridamole echocardiography test (DET: two-dimensional echocardiographic monitoring with dipyridamole infusion up to 0.84 mg/kg in 10 minutes) is a useful tool for the noninvasive diagnosis of coronary artery disease. Aims of the present study were to assess the effects of antianginal drugs on dipyridamole-induced ischemia and to evaluate whether drug-induced changes in DET response may predict variations in exercise tolerance. METHODS AND RESULTS: Fifty-seven patients with angiographically assessed significant coronary artery disease (greater than 70% lumen reduction in at least one major coronary vessel) performed a DET and an exercise electrocardiography test (EET) in random order both off treatment and on antianginal drugs (beta-blockers, calcium antagonists and nitrates, alone or in various combinations). The criterion for DET positivity was a transient dyssynergy of contraction absent or of a lesser degree in the baseline examination. In DET, two parameters were evaluated: the dipyridamole time (i.e., the time from onset of dipyridamole infusion to obvious dyssynergy) and the wall motion score index. DET sensitivity was 91% off therapy and fell to 65% under therapy (p less than 0.01). In the 37 patients who had a positive DET both off and on therapy, the dipyridamole time increased from 6 +/- 3 (off therapy) to 8 +/- 3 minutes (on therapy) (p less than 0.01). The wall motion score index at peak dipyridamole went from 1.38 +/- 0.14 to 1.31 +/- 0.14 (p less than 0.01). EET and DET yielded concordant (positive versus negative) results in 41 of 57 (71%) patients off and in 35 of 57 (61%) on therapy (p = NS). In the subgroup of 38 patients with both positive DET and EET without treatment, the therapy-induced variations in exercise time were significantly correlated with the variations in dipyridamole time (r = 0.5; p less than 0.01), not with variations in wall motion score index (r = 0.3; p = NS). CONCLUSIONS: 1) Antianginal therapy can protect from dipyridamole-induced ischemia and 2) the therapy-induced changes in DET response parallel variations in exercise tolerance and might be useful for the objective, exercise-independent assessment of the therapy efficacy.

Adrenergic beta-Antagonists↗
PubMed1991

How we teach the doctor-patient relationship.

Since the reform of the Italian medical degree in 1988, fourth-year students now study the dynamics of the doctor-patient relationship as part of the compulsory 'methodology of the clinical, therapeutic, prevention and rehabilitation approach' course. This work illustrates a pilot scheme carried out at the Milan University Medical School and begun shortly before the reform of the Italian medical degree. In dealing with the teaching of the doctor-patient relationship, the authors look into a relational-psychological perspective which is supported by notions and instruments intrinsic to medical pedagogy. The work is handled along three main lines: (a) presentation of a relational teaching model and definition of teaching objectives; (b) presentation of the methods and techniques used (role-playing, videotape recordings, video simulation and group work); and (c) discussion on the evaluation criteria.

Curriculum↗
PubMed1990

HLA class I soluble antigen serum levels in HIV-positive subjects--correlation with cellular and serological parameters.

HLA Class I soluble antigen serum levels have been evaluated in 178 subjects who were positive for human immunodeficiency virus (HIV) and in 66 HIV-negative controls. The serum levels of HIV p24 antigen, interleukin 2 receptor (IL 2r), CD8 soluble antigen (CD 8ag), B2-microglobulin (B2-m), and neopterin (Npt), as well as the number of CD4+ and CD8+ T cells were also evaluated. Results show that mean HLA class I serum levels of HIV-positive subjects: (1) are significantly higher than controls (p less than 0.001); (2) increase with disease progression (67.7 RU/ml, 103.4 RU/ml, and 169.6 RU/ml for subjects belonging to groups II, II, and IV of the Centers for Disease Control [CDC] classification, respectively); (3) correlate with HIV p24 antigen, IL2r, and CD 8 soluble antigen levels. Present data show that elevated levels of HLA class I soluble antigens, correlating with disease stage, are found in sera of HIV-positive subjects. Circulating HLA class I molecules, interfering with some immune functions, might contribute to the pathogenesis of the immune deficiency of HIV-positive subjects.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

Luminescent immunoassay using isoluminol derivatives.

Isoluminol derivatives (ID) were early employed in the preparation of tracers for immunoassay. Their wide use was mainly due to their high quantum efficiency, low molecular weight, well-known chemical structure, low cost and high stability. Moreover the light efficiency of some ID may be modified by specific binding to the antibody, thus allowing the development of homogenous immunoassays requiring no bound/free separation step. Some ID are commercially available under both the amino terminal and carboxyl terminal form for conjugation to respectively carboxy derivative of steroid and amino residues of protein. The linking reaction can be commonly carried on via active esters chemistry and can be easily accomplished within one day. Steroid conjugates can then be rapidly purified by silica gel thin layer chromatography, and protein conjugates by gel filtration on a short disposable column. In the field of steroid studies, isoluminol derivative conjugates were prepared for the immunoassay of almost all compounds of clinical interest. When dealing with protein, both antigens and antibody were labelled in this way, resulting in highly specific activity tracers for competitive and non-competitive immunoassays. Recently the labelling of streptavidin with amino-buty-ethyl-isoluminol allowed the development of very sensitive immunoassay methods which take advantage of the biotin-avidin system.

Avidin↗
PubMed1989

A chemiluminescent immunoassay for the direct measurement of urinary 5 alpha-androstane-3 alpha, 17 beta-diol-glucuronide in urine.

We described a chemiluminescent immunoassay (CIA) for 5 alpha-androstane-3 alpha, 17 beta-diol-glucuronide (3 alpha-diol-G) in human diluted urine. This method allowed the direct measurement in 1 microliter of urine avoiding the hydrolysis and extraction steps for sample pretreatment commonly used in routine methods. The hapten 3 alpha-diol-G was synthesized by a Koenigs-Knorr reaction. The immunogenic complex, 3 alpha-diol-G conjugated to bovine serum albumin (BSA), was employed to induce the formation of specific antibodies in New Zealand rabbits. In addition, the required chemiluminescent (CL) tracer was prepared. The characteristics of the antibody was determined as regard to specificity and sensitivity and the precision of the assay methods established. In 22 hirsute women affected by polycystic ovarian syndrome we found 3 alpha-diol-G values significantly (p less than 0.01) higher (146.28 +/- 73.77 micrograms/g of creatinine; mean +/- SD) than those observed in normal women (72.1 +/- 32.58 micrograms/g of creatinine; mean +/- SD).

Adult↗
PubMed1989

Configuration and optimization of a common two-site immunoassay for human prolactin using a chemiluminescent tracer and an enzymatic tracer.

We have developed a two-site immunoassay for human prolactin using two monoclonal antibodies: one of them immobilized on the solid phase and the other labelled with biotin. The serum is incubated simultaneously with the antibody-coated bead, the biotinylated antibody and the tracer (streptavidin-isoluminol or avidin-peroxidase complex). Our experimental work has been directed towards a common set of reagents to capture the prolactin and then, with different tracers, towards obtaining on the calibration curve the same results for unknown samples. On the basis of the positive results we obtained, we have developed a kit that can be used by the customer or as an enzyme-immunoassay or as a chemiluminescent immunoassay, depending on instrumentation available, spectrophotometer or luminometer.

Antibodies, Monoclonal↗
PubMed1989

Methodological problems of direct bioluminescent ATP assay in platelets and erythrocytes.

Direct bioluminescent ATP determination in platelets and erythrocytes involves the study of different parameters which are discussed here. Some parameters are linked to the bioluminescent reaction and to the analyte (ATP); others have regard to the biological matrix. The composition of bioluminescent reagents and the preparation and conservation of the ATP standard, also in the presence of excipients, are among the first given. Matrix problems involve cell characteristics related to age and form, lysis resistance and the possible formation of aggregates (platelets) that may inhibit the complete release of ATP. For these reasons we used the most efficient ATP release agent with the lowest inhibitory effect on luciferase. The data obtained correlate well with a bioluminescent method requiring extraction with ethanol/EDTA, and therefore more time, for ATP determination in platelets and erythrocytes.

Adenosine Diphosphate↗
PubMed1989

Lesion detection in MS patients with and without clinical brainstem disorders: magnetic resonance imaging and brainstem auditory evoked potentials compared.

The findings of the present study can be summed up in the following points: (1) brainstem auditory evoked potentials (BAEP), as compared with magnetic resonance imaging (MRI), has a greater capacity and a lower cost in disclosing brainstem plaques both in MS patients with symptoms or signs of actual brainstem involvement and in clinically silent ones. This makes BAEP a useful technique for the neurologist, who can confirm the clinical suspicion of a brainstem lesion and follow the evolution of the disease in the patient. (2) The sensitivity of BAEP is lower than that of MRI as far as the anterior lesions of the brainstem are concerned. (3) MRI is more specific than BAEP, inasmuch as several types of injuries can alter the BAEP, while the demyelinating plaque has a specific image and can only be confused with little lacunar infarcts. (4) Plaques that produced symptoms or signs in the past can eventually disappear and be no longer detected by a subsequent MRI.

Adolescent↗
PubMed1989

[Neuro-AIDS: a multicenter neuroradiological study].

The results are described of a retrospective multicentric CT/MR study of 141 neuro-AIDS patients (IV group CDC classification); 114 patients were drug addicted, 13 homosexual, 8 polytransfused, and 6 had other risk factors. The mean age was 29.6 years. The pathologic agent was identified in 47 cases by c.s. fluid examination, biopsy, autopsy or specific treatment response: it was HIV in 20 cases, toxoplasmosis in 11, cryptococcosis in 9, leishmaniasis, salmonella and papovavirus in single cases. In the follow up of 2 cases, a Kaposi's sarcoma and a primitive CNS lymphoma occurred. The main clinical features were AIDS-dementia complex (45% of cases) and focal neurologic manifestations (36%). The neuroradiological protocol consisted of 238 CT exams (97 controls), most of them with DDD (delayed double dose) technique, 7 MR exams (0.15 T) and 2 angiographies. CT findings were divided into 3 groups: negative (16%), atrophic (47%) and focal lesions (37%). In the first and second group, HIV and cryptococcal infections were the main pathologic agents. In the third group toxoplasma infections were discovered, and TB granulomas and other pathologic conditions, with ring-like or nodular enhancement, in cortical/cortico-medullary location. In follow-up patients a high tendency of evolution towards focal lesions was observed, even in negative cases. The DDD enhancement technique allowed in most cases both the demonstration of very small lesions and their grading. According to the literature CT, though a highly sensitive method, is inferior to MR imaging; however our experience in this field is currently insufficient. The specific diagnosis of pathologic agents of neuro-AIDS is difficult, due to the high number of opportunistic AIDS-related infections and neoplasms, with overlapping features: differential diagnostic criteria can be assessed only by comparing the clinical, microbiological, topographic, CT and MR findings. CT and MR exams are necessary to guide and monitor therapy and to plan stereotaxis biopsy.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Lower cranial nerve palsy produced by internal carotid artery dilatation. Report of two cases.

We report two cases of lower cranial nerve palsies (XII in case 1, IX-X-XII in case 2) associated with abnormalities of the internal carotid artery at the base of the skull. In case 1 a limited dissection of the carotid wall produced both paresis of the hypoglossal nerve and Horners syndrome by compression of the nerve trunk against the base of the skull and stretching of the periarterial sympathetic fibres respectively. In case 2 we speculate that a narrow angled kinking of the internal carotid artery may have damaged cranial nerves IX, X and XII by interfering with the blood supply to the nerve trunks. In both cases the outcome was favorable with almost complete regression of the initial symptoms. We conclude that the association between lower cranial nerve disturbances and internal carotid artery abnormalities is probably more common than was thought. We suggest that the pathogenesis of the damage to the cranial nerves may differ from one case to the next.

Adult↗
PubMed1987

Occurrence of lymphocyte proliferative response to thyroglobulin and antithyroglobulin antibodies in normal individuals: lack of correlation with HLA.

Peripheral mononuclear cells (MNC) of patients with autoimmune thyroid disease have been shown to proliferate when cultured with human thyroglobulin (hTg). In addition, such a phenomenon is apparent in a certain number of healthy individuals. In this study we have attempted to correlate hTg-induced MNC proliferation, occurrence of anti-hTg autoantibodies and HLA phenotype (including Class II DR and DQ loci) in a population of HLA-typed normal blood donors. Fourteen out of 56 subjects showed a significant MNC proliferation to hTg. Three of them had anti-hTg autoantibodies in the serum, while none of the hTg-unresponsive subjects showed such antibodies. No correlation with HLA phenotype (including Class II DR5 specificity, referred as associated with Hashimoto's thyroiditis, and DQ alleles) was observed.

Adult↗
PubMed1987

Results of combined surgical and medical therapy in patients with prolactin-secreting pituitary macroadenomas.

To assess the long term effectiveness of combined sequential surgical and medical therapy in the management of prolactin-secreting pituitary macroadenomas, we followed 21 patients for 46 +/- 6 months (mean +/- SE) after diagnosis (range, 12 to 96 months). All patients underwent operation. Six were also treated with bromocriptine, 7.5 mg/day immediately after operation. A group of 15 patients with tumor sizes similar to those of the first group was followed without medical therapy until signs of regrowth of the neoplasia were evident. No patient of the combined therapy group experienced a recurrence of the disease. On the other hand, only 2 patients of the second group were recurrence-free at the end of follow-up. In the other 13 cases, adjunctive therapy had to be established for clinical and radiological evidence of tumor recurrence 26 +/- 7 months after operation. We conclude that combined sequential surgical and medical therapy may be useful in the management of macroprolactinomas. Our hypothesis must be confirmed by studies that compare patients treated with operation plus bromocriptine with patients treated with bromocriptine alone.

Adenoma↗
PubMed1987

Diagnosis, staging, and treatment of juvenile nasopharyngeal angiofibroma (JNA).

Nineteen patients with juvenile nasopharyngeal angiofibroma (JNA) were surgically treated with different techniques from January 1968 through December 1985. Two patients had undergone a previous operation at another hospital; all patients were males (mean age 15.4), and the most common symptom was nasal obstruction (84.2%). Lateral extension into the pterygomaxillary fossa occurred in 14 patients (73.6%), and 2 also had intracranial invasion (10.5%). In five cases, the tumor's cytosol was analyzed for hormonal receptors. Negative values for estrogen and progesterone receptors were obtained, although the content of dehydrotestosterone receptors was highly positive. These results tend to support the hypothesis of JNA's androgen-dependence. The authors emphasize the need of a preoperative staging classification based on clinicoradiological data in selecting the most adequate surgical approach. Tumors with lateral extension into the pterygomaxillary fossa can be easily removed through a midface degloving; large involvement of the infratemporal fossa requires, also, a transzygomatic dissection. In JNAs with intracranial extension a combined intracranial-extracranial approach is advisable.

Adolescent↗