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M Ventura

Publications and source records attributed to M Ventura.

At least 19 recordsLinked to original sources
PubMed1992

[Osteopenia in anorexia nervosa evaluated by dual photon-densitometry. Role of malnutrition and hypogonadism].

30 female patients with anorexia nervosa (AN) were studied and compared with 45 age-matched normal controls. All the patients had severe weight loss and nutritional involvement. Mean and SE body mass index, BMI (kg/m2) were 15.8 +/- 1.8 in anorectics compared to 21.7 +/- 4.7 in normals (p < 0.0001). All the patients presented amenorrhea lasting between 3 and 120 months (mean 24.8 +/- 25.3). A nutritional survey and a dual photon bone densitometry, including spine, hip, total body and total mineral content were performed. The mean values +/- SE in patients and controls were: spine densities (L2-L4) in g/cm2: AN 0.84 +/- 0.1, controls 1.03 +/- 0.1 (p < 0.002). Total mineral content (g): AN mean 1733 +/- 261, controls 2045 +/- 276 (p < 0.0001). In anorectic patients the correlations between bone density and BMI for spine were r: 0.52 (p = 0.002), for hip r: 0.37 (p = 0.04), and total mineral content vs BMI gave r: 0.64 (p = 0.0001). Mean calcium intake in 23 studied patients was lesser than the classic recommended dietary allowance in the whole group, it was less in the pure restricters as compared to vomiters. The relation between duration of amenorrhea and bone density showed than a decrease in the later was evident when the absence of menses was longer than 24 months. In conclusion, in patients with AN there is a real decrease in bone density which is strongly related to low weight and in lesser proportion to the duration of amenorrhea, particularly when it was longer than 24 month.

Absorptiometry, Photon↗
PubMed1992

[Magnetic resonance and arthroscopy of the knee. A double-blind study in 40 patients].

To evaluate the capabilities of ultra-low-field MR for the high-resolution imaging of the knee with a short acquisition time, a prospective double-blind study was carried out on 40 consecutive patients with acute or chronic articular conditions who were examined with both MR imaging and arthroscopy. Three-dimensional gradient-echo MR sequences were employed which allow many thin high-resolution slices to be obtained in a relatively short time. To evaluate the results arthroscopy, performed the day after MR imaging, was considered the gold standard. MR imaging and arthroscopy were in agreement in 84.6% of meniscal tears with 91.6% sensitivity and 80% specificity, in 82% of anterior cruciate ligament lesions with 100% sensitivity and 80% specificity and in 81% of cartilage lesions with 100% sensitivity and 61% specificity. On the whole, MR imaging and arthroscopy were in agreement in 82.5% of cases with 97.2% sensitivity and 75.3% specificity. MR imaging gave more information about collateral ligament, muscle and bone involvement. These results confirm the capabilities of ultra-low-field MR imaging in the study of the knee: the technique allows diagnostic studies to be performed in a short time, at a low cost, and with similar results to those obtained with higher field strengths.

Anterior Cruciate Ligament↗
PubMed1991

Evaluation of hematoma by MRI in follow-up of aorto-femoral bypass.

We selected a population of 20 patients with atherosclerotic disease, submitted to implantation of aorto-femoral bypass graft. These patients were studied by MRI with T1- and T2-weighted sequences (w.s.) using a 0.5 T superconductive magnet. Investigation was performed at 1 wk, 1, 3, and 6 mo after dacron implantation, to evaluate the normal evolution of hematoma and the potential development of complications. At the first week examination, hematoma presented medium signal intensity on T1 w.s. and high signal intensity on T2 w.s.; at 1 mo control the amount of hematoma was slightly reduced and we found persistence of high signal intensity on T2 w.s.; progressive reduction of size and signal intensity on T2 w.s. was noted at 3 mo control, in patients operated for peripheral vascular disease; on the other hand we found persistence of high signal intensity in T2 w.s. in patients treated for abdominal aortic aneurysms; only after 6 mo it was evident in all patients fibrotic evolution of the collection and low signal intensity in both T1 and T2 w.s. Thus, MRI study was useful in the evaluation of patency, morphology, and in detection of intraluminal thrombosis, but also in the characterization of periprosthetic hematoma.

Aged↗
PubMed1991

[Magnetic resonance: the usefulness of gradient-echo refocusing sequences in the diagnosis of aneurysms of the abdominal aorta].

Sixteen patients bearing aneurysms of the abdominal aorta were studied by means of a 0.5 T MR unit. Spin-echo T1-weighted sequences and gradient-echo refocusing sequences were performed. All patients were previously submitted to US; in 8 cases angio CT was performed, and in 6 patients angiography of the abdominal aorta. A comparative analysis with the US findings showed a high correlation coefficient for the maximum diameters (R = 0.93) while site and size evaluations were not accurate. A very high correlation coefficient for the maximum diameters (0.97) was found at the comparative analysis with CT findings, while in two cases an erroneous suprarenal location was described. Angiographic examination provided valuable information about renal and iliac involvement, but the maximum diameters could not be accurately assessed. Spin-echo MRI allowed good evaluation of the maximum size, of location and extent of the aneurysm, as well as of iliac involvement; this technique, however, was useless in the characterization of the thrombus. Gradient-echo refocusing sequences have proven very useful for the identification of endoluminal contours and for the correct evaluation of the thrombus. Spin-echo sequences, on the contrary, accurately assessed only 7 cases, whereas the diagnosis was uncertain in the remaining 4 patients.

Aged↗
PubMed1991

[Spermatic cord torsion].

Spermatic cord torsion happens rather frequently in young men. It must be discovered early on, to allow for the possibility of removal by surgery. It appears from recently written medical articles that the endocrine function of the testis is protected following several hours of torsion and the risk of immunological damage to the contralateral testis is subsequently reduced.

Adolescent↗
PubMed1990

Abdominal aortic aneurysm evaluation: comparison of US, CT, MRI, and angiography.

We studied 26 cases of abdominal aortic aneurysm with magnetic resonance imaging (MRI), computed tomography (CT), ultrasonography (US), and angiography. Data acquired were compared to those obtained at surgery. Diameter of the aneurysm was correctly defined in all cases by CT and MRI, while angiography underestimated the diameter of lesions without peripheral calcifications. Involvement of renal arteries was present in four cases and correctly diagnosed with MRI and angiography in all of them. CT did provide this information in three cases and US were not useful. Also, iliac arteries involvement was depicted by CT, MRI, and angiography in 10 out of 10 patients. Coronal sections of MRI provided comparable images to those of angiography. By comparing these different techniques we verified the good reliability of MRI as investigation tool for an accurate evaluation of aneurysms; its only limit lying in the poor capability of detecting calcifications.

Aged↗
PubMed1990

Role of magnetic resonance imaging in the evaluation of aortic graft healing, perigraft fluid collection, and graft infection.

The authors report their preliminary experience in the use of Magnetic Resonance Imaging (MRI) in ten patients who underwent aortic reconstruction. Examinations were performed 1, 4, 12 and 24 weeks after surgery, to examine the presence, size, magnetic characteristics and evolution of periprosthetic collections. The results have shown that periprosthetic collection can be considered normal after aortic reconstructive surgery, because such a perigraft collection (PFC) was present in 90% of the patients studied 1 week after operation, and had disappeared within 24 weeks in all cases. The magnetic characteristics were evaluated by T1 [repetition time (TR) = 480 msec and echo time (TE) = 20 msec] and T2 weighted spin-echo sequences (TR = 1800 msec and TE = 70/120 msec). Variations in the magnetic characteristics, found in sequential examinations, correlated with modifications of the collection and suggested that it was originally blood. The MRI examination performed 24 weeks after surgery gave a low signal intensity in T1 and T2 weighted sequences (w.s.) suggesting periprosthetic fibrosis. These preliminary observations may constitute a starting point for better evaluation of the normal appearance and evolution of the periprosthetic fluid collections following aortic graft implantation and, may be useful for the early detection of infection especially in asymptomatic patients.

Aorta, Abdominal↗
PubMed1989

Prevalence of antibodies to hepatitis C virus in Spanish patients with hepatocellular carcinoma and hepatic cirrhosis.

The prevalence of antibodies against hepatitis C virus (HCV) was investigated in 96 patients with hepatocellular carcinoma, 106 patients with liver cirrhosis without evidence of cancer, and 177 controls without liver disease. 75% of patients with hepatocellular carcinoma had HCV antibodies (anti-HCV), a significantly higher proportion than that observed in patients with cirrhosis (55.6%), or controls (7.3%). The prevalence of anti-HCV was significantly higher in patients with alcoholic cirrhosis and hepatocellular carcinoma (76%) than in patients with alcoholic cirrhosis alone (38.7%) whereas in patients with cryptogenic cirrhosis there was no significant difference between those with and without primary liver cell cancer (81.4% and 77.5%, respectively). These results indicate that HCV infection may have a role in the pathogenesis of hepatocellular carcinoma, even in patients with chronic liver disease apparently related to other agents such as alcohol, and that this recently identified hepatitis virus may be found in a large proportion of patients with cryptogenic cirrhosis.

Aged↗
PubMed1989

The relationship between knowledge about acquired immunodeficiency syndrome and the implementation of universal precautions by registered nurses.

The relationship between the level of knowledge of registered nurses (RNs) concerning acquired immunodeficiency syndrome (AIDS)-related issues and the practical observance of universal precautions was studied. It was hypothesized that the more knowledge a nurse has concerning AIDS the more likely he or she is to implement universal precautions. All registered nurses who have direct patient contact (N = 400) and are employed at a Northeastern teaching medical center, were provided a packet of three questionnaires and encouraged to participate. Two hundred thirteen (53%) RNs returned completed questionnaires. Subgroups were examined for trends relating such parameters as age and the amount of AIDS knowledge, using analysis of variance. The major hypothesis was tested by correlating the overall scores for AIDS knowledge and the implementation score. Results indicated no relationship between knowledge and the implementation of universal precautions (r = -0.12). When evaluating scores according to work areas, those subjects with higher knowledge scores had lower practice scores. Other demographic variables showed no influence on either knowledge or implementation scores as measured by this study. Further study is needed to understand what factors will motivate RNs to implement universal precautions.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Cell-mediated immune response in psoriasis and psoriatic arthritis.

It has been previously described an impairment of cell-mediated immune response in psoriasis. In the present paper we have evaluated lymphocyte surface markers, non specific immunity, lymphokine secretion and antibody synthesis in a group of patients with psoriasis (PS) and with anti-inflammatory drug treated or gold-treated psoriatic arthritis (PsA). No significant differences are found in terms of T lymphocyte subpopulation frequency, even if a lower CD8+/CD4+ ratio was observed in all patients. In spite of an increased percentage of B lymphocytes, B cell polyclonal response is significantly decreased in the presence of either T cell-independent or T cell-dependent polyclonal activator. Further studies provide additional supports to these findings, since all psoriatic patients exhibit a deficit of T helper function in an antibody-specific induction system. Gold therapy in PsA led to a partial recovery of T helper function, without affecting the immunoglobulin reduced synthesis. With particular reference to non-specific activities mediated by monocytes and polymorphs (PMN), PMN chemotaxis, phagocytosis and killing and monocyte-mediated phagocytosis are reduced, except for monocyte phagocytosis in anti-inflammatory treated PsA or PMN chemotaxis in gold-treated PsA. Finally, lymphokine release is significantly decreased in all patients. In conclusion, our data provide further evidence for the impairment of immune response in psoriasis and PsA, which may in turn play a key role in the pathogenesis of psoriasis.

Adult↗
PubMed1989

[Magnetic resonance in the characterization of atherosclerotic lesions].

Fifty-one patients with occlusive and dilating vascular diseases were evaluated with MR imaging, using T1 and T2-weighted sequences and an 0.5 T superconducting magnet. Atheromatous plaques were detected in the carotids and on the aortic walls. Fatty lesions had high signal intensity on T1-weighted sequences and could be well distinguished from older thrombotic depositions which presented with medium signal intensity on T1-weighted scans and low signal on T2-weighted images. Thrombotic depositions in aneurysmal dilatation of the aorta and carotid arteries could be distinguished from patent internal lumen; inside them, areas of different signal intensity were demonstrated, which were related to the paramagnetic effect of hemoglobin degradation products (hemosiderin and methemoglobin).

Aorta, Abdominal↗
PubMed1988

Use of a simple method for the Epstein-Barr virus transformation of lymphocytes from members of large families of Réunion Island.

A simple method for the preparation of lymphoblastoid cell lines from small amounts (100 microliter) of frozen whole blood is described. A success score greater than 90% was obtained for EBV transformations using blood samples which had been collected several months before the infection. Due to the simplicity of the technique, up to 80 samples could be processed per day. This technique was used to prepared 242 permanent cell lines from 13 large families from Réunion Island showing blood group H deficiency. These cell lines are now available for genetic studies.

ABO Blood-Group System↗
PubMed1988

Effects of a new multielement buffer on production, ruminal environment, and blood minerals of lactating dairy cows.

Twelve multiparous Holstein cows were used to evaluate the capacity of a multielement compound consisting mainly of northupite and sylvite to alleviate low milk fat percent. Possible mechanisms of action were assessed. Cows were arranged in a 4 X 4 Latin square design replicated three times. Basal diet was 55% concentrate:45% forage fed ad libitum. Dietary treatments were control, NaHCO3 at 1% of diet DM, and multielement buffer at 1 and 3% of diet DM. Feed intake and milk production were similar for all treatments. Milk fat percentages for the four treatments were 2.97, 3.21, 3.43, and 3.67%, respectively. A shift toward a higher molar percent of ruminal acetate and a lower molar percent of valerate appeared to coincide with changes in milk fat percentage. Milk protein percentage also was increased by supplemental multielement buffer. Ruminal fluid acidity was reduced by NaHCO3 and multielement buffer. Extent of in situ digestion of forage DM and cellulose was improved when cows consumed a buffering agent. Rate of corn silage digestion tended toward improvement. As mineral buffer was consumed, concentrations of Mg and K increased in ruminal fluid and blood. As dietary Na intake increased, ruminal and plasma Cl concentrations were depressed and plasma S and Ca were elevated.

Animals↗
PubMed1988

Failure of expression of alpha-3-L-fucosyltransferase in human serum is coincident with the absence of the X (or Le(x)) antigen in the kidney but not on leucocytes.

The X antigen, beta Gal(1----4)[alpha Fuc(1----3)]beta GlcNAc-R, is mostly found in epithelial cells of the digestive tract, proximal convoluted tubules of the kidney, and granulocytes. The alpha-3-L-fucosyltransferase responsible for synthesis of this antigen is normally present in the serum, but we found 2 individuals, a mother and her daughter, who lack more than 90% of the serum fucosyltransferase. They are of African origin and are both Le(a-b-). The young girl suffers from a congenital kidney anomaly: oligomeganephronic hypoplasia. Her kidney tubules are devoid of X antigen. However, her mother and herself normally possess the X antigen on granulocytes and its sialylated form on monocytes. Anephric patients showed reduced serum alpha-3-L-fucosyltransferase activity, suggesting that the kidney contributes to an important fraction of serum enzymic activity. It, therefore, appears that there are distinct genetic controls governing expression of the X antigen in different body compartments. Possibly, different alpha-3-L-fucosyltransferases could be at work in kidney and leucocytes.

ABO Blood-Group System↗
PubMed1988

[Abdominal aortic aneurysms. Comparison of magnetic resonance, ultrasound, CT x-ray and angiography].

Twenty-four cases of abdominal aortic aneurysm were studied by means of MR Imaging, Computed Tomography (CT), Ultrasound (US) and Angiography. MR Imaging gave detailed information on the site and extension of the aneurysm. The extent of branches involvement, the presence of thrombosis, and the adjacent structures were also demonstrated. Major limitations of angiography were its morbility, and the difficult/impossible demonstration of eventual thrombi, and of the adjacent structures. CT, although extremely valuable in emergency cases and in the detection of calcifications, provided insufficient information on the involvement of the vessels originating from the aorta. US proved useful in the screening of abdominal aortic aneurysms, but lacked both the accuracy and the reliability necessary to a complete preoperative evaluation. MR Imaging proves thus to be a good investigation technique for a complete assessment of aneurysmatic lesions. Its major limitation is its inability to detect calcifications, while its major advantages are the accurate demonstration of both blood flow and eventual thrombi, and the multiplanarity and non-invasiveness of the methodology.

Aged↗