PubMed Health⌕ Search

Biomedical subjects

M Ferro

Publications and source records attributed to M Ferro.

At least 73 records · Page 4Linked to original sources
PubMed1993

Effects of aging in retinal image quality.

The retinal image quality characterized by the modulation-transfer function of the eye was measured for two groups of subjects aged in the late twenties and mid sixties, respectively. In both groups, we obtained modulation transfer functions by using a double-pass method under the same experimental conditions: 4-mm artificial pupil, paralyzed accommodation, and objective control of the refractive state and centering. Results showed lower values of modulation in the retinal image for older subjects compared with the younger subjects. The modulation transfer function ratio is similar to that previously found for contrast-sensitivity measurements with subjects in the same age groups. These results suggest that a significant fraction of the loss in spatial vision with age has an optical origin. Apart from the well-known increase in intraocular scattering, there also appears to be an increment in ocular aberration that causes an additional reduction in the contrast of retinal images.

Adult↗
PubMed1993

[Treatment of hypertrophic cardiomyopathy with a combination of carnitine and beta blockaders. Review of the literature. Description of a clinical case and long-term follow up].

In the past decade, strategies for managing heart failure have changed. The use of beta blockers, although still in the experimental stage, has proved effective in some cases. The protective action of beta-blocking agents against chronic catecholamine stimulation may be enhanced by the combination with L-carnitine. This substance plays an important and synergistic role 1) as an important source of energy due to fatty acid oxidation, and 2) by avoiding the accumulation of lipids in the myocardium. The successful follow-up of a case of dilated cardiomyopathy is critically reviewed. Treatment with the L-carnitine-propranolol combination restored cardiac function in a 52-year-old man with dilated cardiomyopathy: a 50% reduction in mitral EPSS (E Point Septal Separation), from 20 to 10 mm was obtained with the above mentioned therapy; as well as a decrease from 60 to 57 mm in diastolic diameter. Our experience suggests promising benefits in adopting beta blockers combined with L-carnitine therapy in myocardial failure secondary to dilated cardiomyopathy.

Adrenergic beta-Antagonists↗
PubMed1993

Removal systems of immunoglobulin A and immunoglobulin A containing complexes in IgA nephropathy and cirrhosis patients. The role of asialoglycoprotein receptors.

BACKGROUND: Whereas the complex removal routes hypothesized for IgA containing immune complexes (IC) and macromolecules can be adequately analyzed by a recently proposed IgA1-IgG aggregate probe (Lab Invest, 66: 86-95), the relative significance of the asialoglycoprotein receptors in IgAIC clearance is still uncertain. EXPERIMENTAL DESIGN: The removal kinetics of 99mTc diethylenetriamine-pentaacetic acid-conjugated asialo alpha 1 acid glycoprotein (AAGP) and 123I-labeled IgA1-IgG aggregate were analyzed in 11 cirrhosis patients and 13 IgAN patients of comparable age. RESULTS: IgA1-IgG aggregate mean plasma clearance rate was delayed in IgA neuropathy (IgAN) patients (slope 0.038 minutes-1, range 0.027 to 0.053) compared with normals (0.047 minutes-1, range 0.038 to 0.053, p = 0.05). The liver was the main organ involved in the IgA1-IgG removal. When compared with normals, (34.3 minutes, range 29.8 to 42.2), the liver mean transit time (MTT) was significantly (p < 0.02) prolonged in IgAN patients (41.3 minutes, 33.6 to 52.3). Participation of spleen in clearance was observed in some patients and was almost invariably concurrent with normal clearance parameters. Conversely, 9 out of 11 cirrhosis patients had a remarkable splenic uptake, but the blood clearance rate was invariably delayed (0.022 minutes-1, 0.014 to 0.028, p < 0.003) and liver MTT extremely prolonged (122.4 minutes, 52.4 to 400, p < 0.003). In IgAN patients with delayed clearance of the IgA1-IgG aggregate, a distinct trend of progression towards renal failure was noted. AAGP clearance was also delayed in cirrhosis patients: slope = 0.166 minutes-1, 0.108 to 0.247, p = 0.05 as compared with both normals (0.230, 0.173 to 0.289) and IgAN patients (0.250, 0.184 to 0.254). Liver MTT in cirrhosis patients was extremely prolonged: 240.6 minutes, 132.5 to 400 minutes, p < 0.007 compared with both normals (90.0 minutes, 82.7 to 96.6) and IgA patients (92.2 minutes, 70.3 to 107.1). AAGP clearance parameters in normals and IgAN patients were not statistically different. MTT values of AAGP and IgA1-IgG aggregate were strictly related (p = 0.008), suggesting that asialoglycoprotein receptors are partially involved in the clearance of the IgA1-IgG aggregate probe. CONCLUSIONS: Some patients with IgAN have a prolonged circulation of an IgAIC miming probe, probably due to an impaired macrophage function. Other possibilities of prolonged circulation of IgAIC in these patients should imply an abnormal IgA glycosylation pattern that allows IC to escape from an effective asialoglycoprotein receptor system. In cirrhosis patients, all of the removal routes of IgA and IgA containing IC are greatly altered suggesting a causative role in the development of an associated, often clinically inapparent, glomerular disease.

Adult↗
PubMed1992

[Postoperative hyperamylasemia: the evaluation of the efficacy of ranitidine in prevention].

The paper examines the role of ranitidine in the prevention of postoperative hyperamylasemia, a complication following major biliary tract surgery, especially if associated with intraoperative cholangiography. Forty patients underwent cholecystectomy and intraoperative cholangiography: calculosis of the choledochus was observed in 11 patients and a revision of the VBP was therefore carried out involving the transcystic insertion of Kehr's tube. Patients were randomly subdivided into two groups: group A (treated with 50 mg ranitidine 4 times a day e.v.) and group B (no anti H2 treatment). No significant differences were noted between the two groups with regard to the onset of hyperamylasemia, although it is worth reporting that ranitidine virtually eliminated all hemorrhagic complications due to ulcer or postoperative gastritis.

Amylases↗
PubMed1992

[Anesthesia for laparoscopic cholecystectomy].

Alterations in the serological, pulmonary and cardiocirculatory parameters, potentially determined by CO2 pneumo-peritoneum during laparoscopic cholecystectomy, require careful intraoperative evaluation. With the aim of verifying the real entity of these alterations, an experience is reported relating to 76 of the 303 patients undergoing laparoscopic cholecystectomy during 14 months. During surgery, besides an obvious increase in pO2, a slight hypercarbia and a slight decrease in pH were observed, which required pharmacological intervention in only 5 cases. In no case did the respiratory and haemodynamic alterations observed necessitate the conversion into laparotomy. This initial experience gives us reason to conclude that careful monitoring of the respiratory parameters leads to an adequate anaesthesiological conduct, and thus facilitates the completion of laparoscopic procedures.

Adult↗
PubMed1992

Comparative assessment of the cytotoxic effects of different xenobiotics in three hepatoma cell lines.

MH1C1, HTC and HEPA 1c1c7 hepatoma cell lines were selected in this study as the bioindicators of the cytotoxicity induced by six chemicals: butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), cycloheximide (CHE), cyclophosphamide (CPA), potassium dichromate (Cr VI) and 2,4-dinitrophenol (DNP). The concentrations used were in the range from 10(-6) mol/l to 10(-2) mol/l, and the exposure time was 24 h. Two end-points were measured to evaluate cytotoxicity: the detachment of dead cells from the monolayer (CS), as evaluated by detection of the total macromolecules present in the cell monolayers solubilized in alkali and the loss of colony-forming efficiency (CF). The dose-response curves were different from one compound to another, but generally similar with the two assays, the colony formation being the most sensitive test. Some technical problems like the toxicity of the solvents at the highest concentrations, the different sizes of colonies, the unspecific cellular detachment due to overgrowth during the experimental time, can be overcome by accurate standardization of the protocols used for each cell line. The sensitivity of the three cell lines was very similar, with some differences in the case of compounds exerting intermediate toxic effects, like CHE and DNP. The most toxic compound was Cr (VI), the least toxic one was CPA. The low cytotoxic effects displayed by CPA could be due to a lack of bioactivation and/or an increase of the inactivating enzymes, which are typical of hepatoma cell lines.

Animals↗
PubMed1991

Comparative subcellular distribution of benzaldehyde and acetaldehyde dehydrogenase activities in two hepatoma cell lines and in normal hepatocytes.

The NAD- and NADP-dependent aldehyde dehydrogenase (ALDH) activities were evaluated in two rat hepatoma cell lines, namely the well-differentiated MH1C1 line and the less differentiated HTC line. Each activity was determined in parallel in isolated rat hepatocytes, for comparison. The aliphatic aldehyde acetaldehyde (ACA) and the aromatic aldehyde benzaldehyde (BA) were used as substrates. With the first substrate the ALDH activities found in the crude cytoplasmic extracts were lower in hepatoma cells than in normal hepatocytes, especially when measured with NADP as coenzyme (ACA/NADP). Otherwise, with benzaldehyde as substrate the NAD-dependent enzyme activity (BA/NAD) was increased about 9-fold in HTC cells over hepatocytes and decreased in MH1C1 cells, while the NADP-dependent (BA/NADP) activity was increased 38- and 2.5-fold in HTC and MH1C1 cell lines, respectively. Studies on the subcellular distribution of these enzyme activities showed that the activity measured with acetaldehyde and NAD (ACA/NAD) was almost equally distributed between the cytosol and the subcellular particles in the three cell populations, but the ACA/NADP activity was shifted towards the cytosolic compartment in hepatomas, especially in HTC cells. The BA/NAD and BA/NADP ALDH activities found in the organelles of hepatoma cells were markedly reduced in comparison with hepatocytes, in favour of the cytosol. The most striking difference between the normal and the transformed cells was the 94-fold increase over hepatocytes of the BA/NADP activity, found in the cytosolic fractions of HTC cells. MH1C1 cells showed a less pronounced (7.5-fold) enhancement of this tumour-associated specific activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetaldehyde↗
PubMed1991

Use of an established cell line in the evaluation of the cytotoxic effects of various chemicals.

The HTC hepatoma cell line was used as an "in vitro" model to detect the cytotoxicity of eighteen chemicals, chosen on the basis of different biological activities and physicochemical characteristics. Two different cytotoxicity assays measuring cell lethality (CS) or inhibition of cell growth (CF) were applicated to confluent cell monolayers or to colony-forming cells, respectively. Cells were exposed to the chemicals at doses ranging from 10(-6) M to 10(-2) M for 24 h. The results indicated a wide range of IC 50 (the concentration resulting in 50% inhibition of toxicity parameters) from as low as 1 microM (Potassium dichromate) to as high as 407.5 mM (Ethanol), the sensitivity of the CF test being greater than that of the CS test. A battery of cytotoxicity tests could be established in order to offer simple, rapid and economic methods which can be complementary and, in part, alternative to the use of laboratory animals.

Animal Testing Alternatives↗
PubMed1991

[Keratitis caused by Pseudomonas aeruginosa and secondary endophthalmitis].

We report three patients with Pseudomonas aeruginosa keratitis. Two patients in the Intense Care Unit had exogenous bacterial endophthalmitis assessed by histopathology; the infection had probably a nosocomial origin and the outcome was fatal. The third case was associated with the use of soft contact lenses and even though clinically endophthalmitis was suspected there was a favourable response to treatment. We review diagnostic aspects and discuss the management of bacterial keratitis and endophthalmitis.

Adult↗
PubMed1990

Cutis marmorata telangiectatica congenita and glaucoma.

A case of cutis marmorata telangiectatica congenita (CMTC) is described in association with congenital glaucoma. Approximately 68 cases of CMTC and only four cases associated with glaucoma have been reported. The type of glaucoma seems to be related to an abnormality of the filtration in the anterior angle, due to increased pressure in the episcleral vessels. The surgical treatment is trabeculectomy, and opening an alternative drainage pathway.

Glaucoma↗
PubMed1990

[Cardiological aspects of pregnancy in women with tetralogy of Fallot. Description of a case of multiple pregnancies and review of the literature].

A case report concerning a patient who received a late surgical correction of a tetralogy of Fallot, at the age of 26, and then had the chance of two pregnancies with no or little risk. The patient was severely cyanotic (erythrocytes 6,440,000/ml-Ht 58.3%-Hb 19.5 g/100 ml) with balanced pressures between the two ventricular cavities and 72 mmHg gradient between right ventricle and pulmonary artery. Before the operation two pregnancies resulted in abortions: the former was before the correction of the cardiac malformation and the latter just after. Then two pregnancies were successful and both the newborn males were healthy and completely free from congenital diseases, and in particular cardiac. Brief examination of literature.

Adult↗
PubMed1989

[Solitary splenic abscess. Clinical picture, diagnosis and treatment].

Splenic abscess, especially the solitary type, is a rarely seen condition, although it has been seen more frequently in recent years. On the basis of a case of splenic abscess with unusual features, the literature on the subject, 171 cases published in Italy, Britain, France and Spain in the past 10 years, is reviewed. It is pointed out that the diagnosis is generally difficult only because abscess is not considered. The diagnostic methods with the best results are ultrasonography and CT scanning, although a checkup after the event showed that straightforward X-ray of the chest, if correctly interpreted, may be enough. Scintigraphy is not indicated and arteriography should only be used in the event of special problems. The clinical picture is scanty and insignificant. The various aetiological agents and changes in these over recent years are illustrated, with special attention with regard to immunodepressed patients. The usual treatment is surgical removal. Other methods with more limited indications, such as drainage and medical treatment, are described.

Abscess↗
PubMed1988

Metabolism of 4-hydroxynonenal by the rat hepatoma cell line MH1C1.

The metabolism of the toxic lipid peroxidation product 4-hydroxynonenal was investigated in the well-differentiated rat heptoma cell line MH1C1. When exposed to 0.1 mM 4-hydroxynonenal (HNE), MH1C1 cells consumed it in a time-dependent manner. There was a linear relationship between the amount of aldehyde consumed and cell number in the range 0.5 - 4 X 10(6) cells ml-1. This process was unaffected by pyrazole, suggesting that alcohol dehydrogenase is not involved. The whole homogenate of MH1C1 cells consumed added HNE at a rate similar to that in intact cells. Fractionation of the homogenate showed that the highest HNE-metabolizing activity is in the cytosol. The dialysed cytosol had almost no capacity to metabolize HNE, but this was restored by supplementation with NAD, NADH, NADP and NADPH. The metabolism of HNE in MH1C1 cells is thus different from that in hepatocytes, which were shown to utilize cytosolic alcohol dehydrogenase for this process. Both reductive and oxidative pathways could be implicated in the metabolic activity of MH1C1 cells towards HNE as well as binding by glutathione.

Aldehydes↗