PubMed Health⌕ Search

Biomedical subjects

E Marchetti

Publications and source records attributed to E Marchetti.

At least 55 records · Page 3Linked to original sources

Immunocytochemical demonstration of estrogen receptors by monoclonal antibodies in human breast cancer: correlation with estrogen receptor assay by dextran-coated charcoal method.

Immunocytochemical demonstration of estrogen receptors in 115 human breast cancer specimens was performed using mouse monoclonal antibodies against estrogen receptor and avidin-biotin as the displaying system. The antibody indicated a highly heterogeneous endowment of neoplastic cells with estrogen receptor at both nuclear and cytoplasmic levels. The percentage of labeled cells within each tumor specimen was recorded to compare this immunocytochemical assay with the biochemical assay of estrogen receptors by the dextran-coated charcoal method. A significant correlation was observed between these two assays. The present results show that estrogen receptors can be confidently demonstrated at the single cell level, thus providing additional information to quantitative biochemical assays. Their prognostic and therapeutic predictive powers may be usefully integrated, particularly in view of the heterogeneous distribution of receptors among cancer cells.

Antibodies, Monoclonal↗

Pathophysiology of estrogen receptors in mammary tissue by monoclonal antibodies.

Identification of preneoplastic lesions of the breast has mainly rested on morphological grounds, supported by epidemiological data. These studies assign a definite precancerous potential to a group of atypical hyperplastic lesions and in situ carcinoma. In spite of much effort no criteria are yet available to understand which, among these lesions, is committed to infiltrative growth, in other words, to understand the risk to a single patient. Estrogens are know to play a critical role in the etiology of breast cancer. The hypothesis is investigated that this role is dependent on a modified expression of their receptor. To approach this question estrogen receptor expression was traced by specific monoclonal anti-receptor antibodies and immunocytochemistry, on a spectrum of breast tissue changes, from normal tissue to infiltrating cancer. Estrogen receptor expression is heterogeneous in normal tissue and in infiltrating cancer, and on the contrary is homogeneous in proliferative atypical lesions and in in situ carcinomas. Present results show that receptor expression is enhanced and becomes homogeneous, maybe constitutive, in atypical hyperplasia and in in situ carcinoma and that this phenomenon could subserve important changes of proliferative capacity which are necessary and possibly sufficient for autonomous growth.

Breast↗

[Changes in the circadian rhythm of urinary cyclic adenosine monophosphate during the alcoholic withdrawal syndrome and related neurobiological correlations].

Urinary cyclic adenosine monophosphate (AMP-c) was measured morning and evening in 35 patients with alcohol withdrawal syndrome (AWS). 65% of the patients revealed a higher night time than day time concentration of AMP-c in the urine, reflecting increased sympathetic adrenergic activity. The circadian rhythm was lost in 88.55% of the 35 patients. The pathogenic factors and mechanisms involved in AWS are discussed and the contribution of sympathetic adrenergic hyperactivity to the onset of the withdrawal syndrome with its concomitant depression of the cholinergic and GABAergic systems is emphasised. Finally it is suggested that insomnia and the loss of REM sleep may also contribute to the onset of the condition.

Adult↗

A monoclonal antibody to human transitional-cell carcinoma of the bladder cross-reacting with a differentiation antigen of neutrophilic lineage.

A monoclonal antibody (MAb) to human transitional-cell carcinoma of the bladder (TCCB) was obtained by immunization of a BALB/c mouse with formalin-fixed TCCB cells and subsequent fusion of the spleen cells with SP2-OAg14 myeloma line. GF 26.7.3 MAb was selected by indirect immunofluorescence (IIF) as reacting agent with target cells and negative with autologous lymphocytes and Epstein-Barr virus (EBV)-transformed lymphoblastoid cell-line. GF 26.7.3 reacts with a high percentage of bladder and colon carcinomas when examined by IIF and immunoperoxidase techniques and cross-reacts with a determinant expressed on neutrophilic cell lineage. The IIF analysis performed on bone marrow and peripheral blood (PB) from healthy subjects and leukemic patients and on leukemic cell lines showed that the expression of the structure detected by GF 26.7.3 is restricted to the neutrophilic cell lineage and first expressed at the promyelocytic level. Immunoprecipitation and SDS-polyacrylamide gel electrophoresis (PAGE) of 125 I-labelled membrane proteins from target cells were performed, but no bands were detected by autoradiography. In addition, pronase insensitivity and periodate sensitivity suggest the possible involvement of a carbohydrate determinant.

Antibodies, Monoclonal↗

[Prolactin in chronic alcoholic liver diseases with and without gynecomastia].

The Authors, after having examined the factors responsible for the hyperprolactinemia in the cirrhotic, confirm the lack of a relationship between the increase in the prolactinic reserve and gynecomastia and between the amount of the prolactinic reserve and the degree of liver disorder. While hyperestrinism and the false transmitters lost most of their pathogenetic importance, other factors such as GABA, the Serotonin and the VIP, offered a new pathogenetic prospective. The prolactin reserve was studied in 63 patients affected by cirrhosis and in 25 affected by fibrosis and hepatic fibrosteatosis, pointing out an increase in the prolactin reserve in 61% of cirrhotic patients and an absence of pathological reports in patients affected by fibrotic hepatopathies. These data confirm the low pathogenetic responsability to be strictly ascribed to ethanol and the preminent role of liver cirrhosis and portal hypertension in the prolactin turnover.

Fatty Liver, Alcoholic↗

[Prolactin in the alcohol withdrawal syndrome. Role of the dopaminergic system].

The basal prolactinemia and the prolactinic reserve were investigated in 30 chronic alcoholics, during the alcohol withdrawal syndrome. In 80% of these patients, the prolactinic reserve was extremely low, while in 16,66% of them was normal or near the lowest limits, recognizing in the exaggerated dopaminergic central activity the responsible pathogenetic mechanism. The dopaminergic hyperactivity fits into a general context of the sympathetic-adrenergic hypertonia, which notoriously plays a primary pathogenetic role in the pathogenesis of the alcohol withdrawal syndrome. In 5 patients with an inhibited prolactin response, a normalization of the prolactin reserve was registered in a test (the same methoclopramide test) carried out after 2-3 months of abstinence from alcoholic beverages, as an evidence of the normalization of the central dopaminergic activity and of a dopaminergic hyperactivity during the alcohol withdrawal syndrome.

Adult↗

[Insulin, peptide C and glucide tolerance in chronic alcoholic hepatopathies].

Changes in blood glucose and insulin metabolism, both under basal conditions and after glucose and glucagon stimulus, were studied in 95 patients with chronic alcoholic hepatopathy. Peptide C was also determined in 19 patients. A high incidence of islet-cell insufficiency was noted. Stress is laid on the multiplicity of the pathogenetic mechanisms responsible for blood glucose and insulin changes during chronic alcoholic hepatopathy, particularly liver cell damage, hyperglucagonaemia, organic and/or functional islet-cell insufficiency, and peripheral insulin resistance. It is felt that the last two of these are of major importance, whereas liver cell damage is of secondary significance, at any rate as far as glucose and insulin turnover is concerned.

C-Peptide↗

[Cyclic adenosine monophosphate (3'5' cAMP) in the alcohol withdrawal syndrome. Clinico-pathogenetic perspectives].

The cyclic adenosine monophosphate (AMP-c) excreted in the urine over a 24 hour period was systematically measured in 40 patients suffering from alcohol withdrawal syndrome (AWS) in varying degrees from slight to delirium tremens. In almost all patients the level of excreted AMP-c was high bul returned to normal when the clinical picture together with arterial pressure and cardiac frequency, was normalised. This shows the primary importance of the central sympathetic-adrenergic system in the pathogenesis of AWS and the value of monitoring urinary AMP-c excretion during the syndrome.

Adult↗

Origin of eye movements induced by high frequency rotation of the head.

Perception of stability of the visual world and control of ocular fixation and tracking are altered in subjects submitted to high frequency vibration. Studies of the eye movements induced in man by passively rotating the head sinusoidally around a vertical axis show that beyond 8 Hz, the amplitude of the eye movements increases and reaches 2.5 times the amplitude of head movement at 30 hz. The high amplitude eye oscillation may, at least in part, explain the perception of visual world instability and the decrease of visuo-oculomotor system performance in man submitted to high frequency vibration. Two interpretations of this phenomenon have been proposed (9). High amplitude eye movements induced at high frequency may be due to either a non-linearity of the vestibulo-ocular reflex (VOR) or mechanical resonance oscillations of the orbital apparatus. To test these hypotheses, baboons were trained to fixate visual targets. Each animal's head was rigidly attached to a rotating frame through a block of dental cement bolted to the skull. Head rotation was produced by a servo-controlled vibrator. Rotations in the frequency range 1 to 20 Hz were successively applied with the animal in darkness or fixating a stationary target. The results showed that gain curves obtained with baboons are similar to those obtained with man. Paralysis of the muscles of one eye by injection of lidocaine disclosed a behavioral asymmetry of the two eyes at low frequency. The paralysed eye showed no movement below 8 Hz, while the normal eye behaved as in the normal situation. Beyond 8 Hz, the gain of the treated eye increased gradually so that beyond 12 Hz, the two eyes responded.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

High-frequency vestibulo-ocular reflex activation through forced head rotation in man.

The dynamic characteristics of the human vestibulo-ocular system were studied in the 0.5-30 Hz frequency range by rotating the head around a vertical axis. The rotation produced by a powerful servo-controlled vibrator was transmitted to the head by a hard-cushioned helmet and a rigid bite bar. The vestibulo-ocular reflex (VOR) gain and phase were measured during fixation of a mobile or stationary visual target and in total darkness. In a second set of experiments, the subjects evaluated the amplitude of the perceived visual instability of the target in the two fixation conditions. The results confirm earlier observations describing the VOR gain and phase in the 0.5-8 Hz range: the gain starts to decrease beyond 2 Hz and the phase rises towards 90 degrees. Beyond 8 Hz, the gain curve reverses direction and increases continuously toward 3-4 at 25-30 Hz in the three tested situations. Meanwhile, the phase curves do not vary much. In the same frequency range, the perceived visual instability is significantly altered. Therefore, the gain variation at high frequency may, in part, explain the perceived visual target instability and may be suspected of altering visually controlled tracking executed in vibrating environments.

Adult↗

[Development and training of monocular motor control].

Misalignment of the visual axes of the eyes observed in strabismus may result from sensory, motor, and/or central nervous system disorders. The functional properties of a technique designed to increase, through training, the monocular motor control of normal human subjects was evaluated, the ultimate goal being obviously to apply the technique to cases of minor strabismus. The subject is seated in front of a television screen. A diaphragm extending from the subject's head to the screen divides the picture into two visually separated half fields. A micro-computer was programmed to project two patterns on the screen, made up of vertical green and grey bars (spatial frequency, 3 deg.). Displacement of the two visually superposable half fields could be independently achieved. The subject's task was to fixate, with one eye, the corresponding half field maintained stationary and track, with the other eye, the motion of the second half field. Perfect fusion of the two half fields has to be preserved during movements of the mobile half field over 2 to 6 degrees at a frequency of 0.4 Hz. The results show that after a few training sessions, subjects developed a high gain monocular motor control. This observation suggests that the method may be used as therapy to correct minor strabismus with or without anomalous retinal correspondence, and offers the possibility to study static and dynamic characteristics of Panum's areas and particularly their modifications as a function of training of monocular motor control.

Adolescent↗