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Biomedical subjects

A Villa

Publications and source records attributed to A Villa.

At least 307 records · Page 17Linked to original sources
PubMed1987

[Sliding massive hiatal hernia: diagnosis using computerized axial tomography].

The radiological features of one patient, entirely asymptomatic, with a paracardiac mass in the right lower lobe, are presented. Computed tomography (TC) evaluation of the chest has shown with remarkable accuracy a massive hiatal hernia, containing the whole stomach and fatty omental tissue. This case confirms TC validity as an accurate and non invasive method in differential diagnosis of chest radiological opacities and its utility to identify seat and composition of diaphragmatic hernias.

Aged↗
PubMed1987

[Electrocardiographic changes in acute carbon monoxide poisoning].

Various electrocardiographic alterations (variations in the repolarisation phase, disturbed conduction, arrhythmias) have been reported in acute carbon monoxide poisoning. In the 44 cases of this poisoning examined, electrocardiographic alterations are also considered in relation to the degree of poisoning (expressed as plasmatic levels of carboxyhaemoglobin-HbCO). In 68% of these cases alterations were presented by signs of subepicardiac or subendocardiac damage. Attacks of atrial fibrillation, premature beats and episodes of sinusal tachycardia were also observed. Almost all these electrocardiographic alterations were quickly reversible. It is concluded that there is no correlation between HbCO levels and electrocardiographic alterations (that were in fact more frequent in the slight poisoning cases).

Adolescent↗
PubMed1987

Glucocorticoids regulate insulin binding in a rat glial cell line.

We have examined insulin receptor regulation by glucocorticoids in the C6 rat glioma cell line. Dexamethasone decreased insulin binding to intact cell monolayers in a dose and time-dependent fashion. The effect is maximal between 48 and 72 h with 50 nM dexamethasone that decreased binding by 40-60%. The natural steroid corticosterone produced a similar effect although it was less potent, and the antiglucocorticoid 17 alpha-methyltestosterone was ineffective in lowering the receptor and partially antagonized the effect of dexamethasone. Total number of binding sites was decreased by glucocorticoids, and when analyzed with a two-site model a 3-fold increase in the dissociation constant (Kd) of the low affinity site was also observed. In the absence of protein synthesis the receptor accumulates at the cell surface, since cycloheximide produced a large increase of insulin binding. Cycloheximide totally blocked the effect of dexamethasone when both compounds were added together to the cells suggesting that protein synthesis is necessary for the effect of the glucocorticoid. By contrast, in cells pretreated with dexamethasone, cycloheximide was unable to produce an increase in cell surface receptor, showing that glucocorticoids probably deplete not only membrane receptor but also total cellular receptor.

Animals↗
PubMed1986

[Sudden death. Cardiac and noncardiac causes].

The present review systematically reports the literature on a phenomenon that is hard to understand not so much in terms of pathological anatomy as in its physiopathological aspects: sudden death. An analysis is presented of the various cardiac and non-cardiac causes that can create the electrical instability of the heart that will end in sudden death. The anatomopathological need for careful study of the structures responsible for the creation of the electrical impulse and its conduction inside the heart is also emphasised.

Asthma↗
PubMed1986

Induction of cytotoxicity by interleukin-2 in T gamma-lymphoproliferative disorders.

We have studied 7 patients with T gamma-lymphoproliferative disorders, in whom 78-88% of circulating nonadherent lymphocytes had the morphology of large granular lymphocytes (LGL) as assessed by light and transmission electron microscopy. The main common features of the membrane phenotype of these LGL expansions included expression of T3, HNK-1 and AB8.28. Other monoclonal antibody-defined surface markers of LGL (OKM1, B73.1, N901) were variably expressed or absent in these patients. Patients' LGL had little or no natural killer (NK) activity but mediated antibody-dependent cellular cytotoxicity (ADCC). Exposure to interferons (type B or gamma) for 20-72 hr resulted in no appreciable induction of cytolytic activity. In contrast, culture in the presence of interleukin-2 (IL-2) for 3 days resulted in the expression of strong cytolytic activity in all the patients tested against an NK-susceptible (K562) and an NK-resistant (Daudi) target. The expression of T3 antigen, the low levels or lack of native NK activity and the induction of consistent cytotoxicity by prolonged exposure to IL-2 led us to suggest that the cells expanding in these subjects are related to the effectors involved in lymphokine-activated killer (LAK) activity.

Adult↗
PubMed1986

Regulation of glycerol phosphate dehydrogenase and lactate dehydrogenase activity by forskolin and dibutyryl cyclic AMP in the C6 glial cells.

We have compared the effects of norepinephrine, forskolin, and dibutyryl cyclic AMP (Bt2cAMP) on the regulation of the cytosolic enzyme glycerol phosphate dehydrogenase (GPDH) in the C6 rat glioma cell line. Forskolin and Bt2cAMP elicit a dose-dependent increase in the levels of the enzyme that was, however, unaffected by norepinephrine. The half-maximal effect of forskolin was obtained at 7-8 microM, and the effect was maximal at 30 microM. Dexamethasone at a 50 nM concentration produced a two- to sixfold induction of GPDH after 48 h. The combination of dexamethasone with forskolin or Bt2cAMP leads to an elevation in GPDH levels that is higher than that produced by one of the compounds alone. This potentiation is found when both agents are added together with or after the glucocorticoid. The increase in uninduced and dexamethasone-induced GPDH activity was blocked by cycloheximide and actinomycin D, indicating that de novo protein and RNA synthesis are required. The activity of cytosolic lactate dehydrogenase activity did not change after incubation with dexamethasone, but increased with forskolin or Bt2cAMP.

Animals↗
PubMed1986

Identification and characterization of L-triiodothyronine receptors in cells of glial and neuronal origin.

High affinity-low capacity binding sites for thyroid hormone have been identified in the nuclei of glial (C6) and neuronal (Neuro 2A) cultured cells. Equilibrium dissociation constants, determined by Scatchard analysis, were very similar in both types of cells (0.2-0.3 nM). The relative affinity of hormonal analogs was also similar: the affinity for T3 was lower than for triiodothyroacetic acid and higher than for T4 or tetraiodothyroacetic acid. The sedimentation coefficients obtained by gradient centrifugation of nuclear receptor extracted with 0.4 M KCl or excised by micrococcal nuclease digestion were 3.5 S and 6.5 S, respectively. These results suggest that the thyroid hormone receptor is not restricted to neuronal cells, but also appears in cells of glial origin.

Animals↗
PubMed1986

[Heart transplants. The value of computerized tomography].

In 9 of 12 patients who underwent cardiac transplantation computed tomography was performed. In 5 of them CT was obtained also before the surgical treatment. In all patients angio-CT technique was performed, while the ECG-gated technique was employed only before surgery. CT shows changes in morphology of both atria but over all of the right one, and rotation of the heart on the longitudinal axis. The conditions of the pericardium are particularly well demonstrated: in 5 cases pericardial effusion was observed, 3 times localized and 2 times diffuse. Only in 1 patient a small thrombus in the right atrium was demonstrated. CT allows the possibility to obtain simultaneously information on mediastinum, lungs and pleura. Pleural effusion, pulmonary infections and mediastinal complications are easily demonstrated.

Adult↗
PubMed1986

[Substances with antibacterial and antifungal activity. I. Synthesis and microbiologic activity of imidazolylmethylanilines].

The synthesis and antifungal activities of many derivatives of 1-(2-imidazolylmethyl)aniline and of 1-(4-imidazolylmethyl)aniline are reported. Antimicrobial data in comparison with miconazole show that many compounds containing chlorine atoms and nitro group exhibit an interesting antimycotic activity. The results obtained are discussed on the basis of structure-activity relationships.

Aniline Compounds↗
PubMed1986

[Application of the Ilizarov technic in the lengthening of the humerus].

Lengthening of the humerus has been considered to be particularly risky because of the danger of neurological damage. The Ilizarov technique makes it possible to avoid complications. The authors have performed eight such lengthenings, with gains in length of 8 to 16 cms. Only one case was complicated by an ulnar and radial paralysis which recovered secondarily.

Achondroplasia↗
PubMed1985

In vitro migration of human large granular lymphocytes.

Large granular lymphocyte (LGL)-enriched peripheral blood mononuclear cells were prepared on discontinuous gradients of Percoll. Migration into nitrocellulose filters was studied in a 2-hr assay with the use of modified Boyden chambers. LGL migrated into filters in response to casein or C5a. Migration depended on the presence of a concentration gradient of chemoattractant between the lower and upper compartment of the chambers. Percoll-purified high density small lymphocytes had little or no migratory capacity under these conditions, requiring a longer incubation time (4 hr) for consistent migration. Migratory capacity in response to stimuli correlated with the frequency of LGL in the various fractions of Percoll gradients. Fractionation of LGL-enriched Percoll preparations with monoclonal antibodies and immunoadsorbent columns or a cell sorter revealed that cells with migratory capacity in response to stimuli were B73.1+ and OKT3-, thus confirming that migrating cells were LGL. LGL preincubated with interferon (IFN) showed enhanced spontaneous motility but no increased responsiveness to chemoattractants. IFN did not modify the migratory capacity of small lymphocytes. The prompt migration of LGL in response to stimuli is consistent with the hypothesis that these cells may serve as one of the first easily mobilizable lines of resistance against infectious agents and tumors. The migration assay described here may offer a better insight into the functions and regulation of LGL.

Caseins↗
PubMed1985

[Treatment of septic or non-septic diaphyseal pseudoarthroses by Ilizarov's monofocal compression method].

The treatment of non-union of long bones is one of the best indications for the use of Ilizarov external fixation. The method is somewhat expensive but without risk. In 20 patients, use of the technique achieved healing in cases in which traditional methods such as bone grafts, plates or other types of external fixator had failed. The main advantages are avoidance of further vascular disturbance, a stable and elastic fixation and the possibility of early weight-bearing with consequent compression.

Adolescent↗
PubMed1985

Pyrrolnitrin analogues. XI--Synthesis and microbiological activity of new 1,4- and 1,5-diarylpyrroles.

The synthesis and microbiological activities of new 1,4- and 1,5-diarylpyrroles is reported. Antimicrobial data in comparison with fungal antibiotic pyrrolnitrin confirm an interesting antimicotic activity of 1,4-diarylpyrroles. On the contrary 1,5-diarylpyrroles show antibacterial activity and an unexpected antimicotic activity. The position of the 4-nitrophenyl group at C4 or C5 of the pyrrole ring influences antibacterial activity.

Anti-Bacterial Agents↗
PubMed1984

Growth-hormone releasing factor and clonidine in children with constitutional growth delay. Evidence for defective pituitary growth hormone reserve.

Six male prepubertal children with constitutional growth delay (CGD), and a subnormal growth hormone (GH) response to insulin hypoglycemia, and four normal prepubertal children were given in different occasions 1 microgram/Kg iv synthetic hpGRF-40 or a single oral dose of 0.15 mg/m2 clonidine (Clon), an effective growth hormone (GH) secretagogue. In the normal children brisk and clear-cut GH rises were detected in plasma after hpGRF-40 (peak GH levels at 15-30 min) or clonidine (peak GH levels 60-90 min). In CGD children hpGRF-40 induced a biphasic response, e.g. a slight increase in plasma GH at 15 min followed by a delayed and erratic GH rise occurring 45-120 min post-injection. Also the GH response to Clon was sluggish and delayed and peak plasma GH levels were attained only 90-180 min post-drug administration. These data indicate that the CGD children of our study have a defect in the pituitary GH reserve.

Child↗
PubMed1984

Monoclonal antibody-defined surface markers of effector cells involved in human monocyte cytotoxicity.

Human adherent peripheral blood mononuclear cells were cytotoxic in vitro against the murine TU5 line in a 48-hr [3H]thymidine-release assay. Monocyte-enriched adherent cell preparations contain a small and variable (usually less than 5%) contamination with large granular lymphocytes as assessed by morphology and staining with monoclonal antibody markers B73.1 and HNK1. To assess whether killing was in fact mediated by monocytes, mononuclear cells or monocyte-enriched preparations were separated using monoclonal antibodies directed against mononuclear phagocytes (Mo2, UCHM1, B44.1) or natural killer (NK) cells (B73.1 and HNK1), and a fluorescence-activated cell sorter. Cells positive for monocyte markers were highly cytotoxic against TU5, whereas negative cells were not. B73.1+ or HNK1+ cells had little or no activity. Cytotoxicity of cells positive for monocyte markers (Mo2, UCHM1, B44.1) was augmented by in vitro exposure to lymphokines or less frequently to interferon (IFN). However, cells negative for these monocytes markers were also stimulated to kill TU5 by lymphokine or IFN to an extent similar or greater than that of positive ones. IFN or lymphokines induced killing of TU5 by monocyte-depleted, B73.1-positive, lymphoid cells. These observations demonstrate that human monocytes do kill tumor cells, either in the absence of deliberate stimulation or after exposure to agents such as lymphokines. However, the possible contribution to "monocyte" cytotoxicity of minor NK cell contaminants must be taken into account particularly when agents such as IFN and lymphokines are applied, even when a relatively NK-cell-resistant target such as TU5 is used.

Antibodies, Monoclonal↗
PubMed1984

Rapid killing of actinomycin D-treated tumor cells by human mononuclear cells. I. Effectors belong to the monocyte-macrophage lineage.

Preincubation of tumor cells with actinomycin D (Act D) rendered various murine and human lines susceptible to killing by unstimulated human peripheral blood mononuclear cells (PBM) in a 6-hr 51Cr-release assay. The murine WEHI 164 sarcoma was selected for analysis of drug-dependent cellular cytotoxicity (DDCC) because high levels of killing were detected with this tumor, and it was considerably resistant to natural killer (NK) cell activity. Optimal conditions for induction of susceptibility to lysis included a 3-hr preincubation with 1 microgram/ml Act D. Effector cells of cytotoxicity against Act D-treated WEHI 164 cells were plastic adherent (greater than 85% monocytes). Cells nonadherent to plastic and nylon wool (less than or equal to 1% monocytes) had no appreciable DDCC activity. In contrast NK activity against K562 cells was mediated by nonadherent cells. When PBM were fractionated on a one step discontinuous gradient of Percoll designed to enrich for monocytes (greater than 90% pure), DDCC activity was found in the monocyte fraction, and the lymphoid cell-enriched fraction had no cytotoxicity against Act D-treated WEHI 164 cells. In contrast, NK activity against K562 was recovered with lymphoid cells, and monocytes had no NK cytotoxicity. Upon fractionation on a six step Percoll gradient designed to enrich for large granular lymphocytes (LGL), the denser lymphocytes (fraction 4-6) and the less dense LGL with NK activity (fraction 2-3) had no cytotoxicity against Act D-treated WEHI 164 sarcoma cells. DDCC activity sedimented in fraction 1 in association with monocytes. PBM were fractionated according to monoclonal antibody-defined surface markers by using a fluorescence-activated cell sorter. Effector cells of DDCC were positive for monocyte markers (Mo2, UCHM1) and were negative for NK cell (B73.1, HNK1), T cell (T11), and B cell (Leu-10) markers. Macrophages obtained by culturing blood monocytes in vitro for 5 to 10 days had DDCC activity. Similarly, peritoneal and bronchoalveolar macrophages had considerable cytotoxicity against Act D-treated target cells, whereas minimal or no NK activity was found at these anatomic sites. Cells of human or murine origin, preincubated with Act D for 3 hr, were heterogeneous in their susceptibility to monocyte killing in a 6-hr 51Cr-release assay. High levels of cytotoxicity were observed with the murine WEHI 164 sarcoma and 3T3 "fibroblast" line and with the human CEM leukemia. Monocytes were weakly (but significantly) cytotoxic against the ALAB breast carcinoma (human) and the 8387 sarcoma (human).(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1983

Infantile hepatic hemangioendothelioma treated by radiotherapy.

Infantile hepatic hemangioendothelioma is a rare tumor of infancy, sometimes associated with cutaneous hemangiomatosis. It is clinically evident within the first six months after birth and can be life threatening because of heart failure, intraperitoneal hemorrhage or thrombocytopenia. In less severe forms spontaneous regression has been described. Current treatment may be surgical ligation of the hepatic artery, or pharmacological therapy with corticosteroids or radiotherapy. A 4-month infant is described, admitted with acute heart failure and huge hepatomegaly. Since a surgical approach was not possible and corticosteroid therapy failed to achieve the expected effect, radiotherapy was given with excellent results.

Hemangioendothelioma↗