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Biomedical subjects

M Molinari

Publications and source records attributed to M Molinari.

At least 127 records · Page 7Linked to original sources
PubMed1984

The thalamo-caudate versus thalamo-cortical projections as studied in the cat with fluorescent retrograde double labeling.

The distribution of thalamic cells projecting to the head of the caudate and their interrelations with thalamo-cortical cells were studied in the cat with different combinations of fluorescent tracers. Injections in the head of the caudate were combined with the injections in the pericruciate, proreal, suprasylvian, anterior cingulate, occipital and ectosylvian cortices. The following results were obtained: (i) Injections in the head of the caudate resulted in retrograde labeling of thalamic cells medially and laterally to the anteromedial (AM) nucleus, and in the medioventral part of the ventral anterior (VA) nucleus. Further, labeled cells were distributed throughout the anterior intralaminar central medial (CeM), paracentral (Pc) and central lateral (CL) nuclei, and the posterior intralaminar center median-parafascicular complex (CM-Pf). Labeled cells were mainly grouped in the mediodorsal parts of the anterior intralaminar nuclei; they were also found in the more dorsal part of the mediodorsal (MD) nucleus, ventral to the thalamic paraventricular (Pv) nucleus and to the habenular complex. (ii) Thalamo-cortical and thalamo-caudate cells overlapped in the medial part of the VA; in the anterior intralaminar nuclei they were either intermingled or were distributed in separate clusters or longitudinal bands. The two cell populations also overlapped in the posterior intralaminar complex. The greatest overlap occurred with the thalamic cell population projecting to the pericruciate cortex. (iii) Thalamic cells bifurcating to the head of the caudate and to the pericruciate cortex were found lateral to the AM, within the VA, and throughout the anterior intralaminar nuclei, especially in the CeM and in the posterior part of the CL; a few branched cells were also found in the CM. Thalamic cells bifurcating to caudate and anterior suprasylvian cortex were also found in the VA. Very few cells (scattered in the anterior thalamus lateral to the AM, as well as in the CeM, Pc and CL) were found to bifurcate to the head of the caudate and the other cortical fields here examined.

Animals↗
PubMed1984

Nitrogen analogues of phencyclidine: 1-alkyl-4-phenyl-4-(1-piperidinyl)piperidines.

In order to investigate the effect of the introduction of a nitrogen atom in the alicyclic moiety of phencyclidine (PCP) a series of 1-alkyl-4-phenyl-4-(1-piperidinyl)piperidines were synthesized. The in vivo assays in mice and EEG in rabbits indicated that the presence of a second basic center in the molecule resulted in a loss of PCP-like activity. The new compounds were devoid of analgesic activity.

Animals↗
PubMed1983

Claustroneocortical projections studied in the cat by means of multiple retrograde fluorescent tracing.

The topographical interrelations of claustroneocortical cells and their degree of divergent collateralization were investigated in cat by means of retrograde fluorescent double labeling. The tracers Fast Blue (FB) and Nuclear Yellow (NY) were injected in several combinations in two different cortical fields. FB-labeled and NY-labeled cells were found in all cases in the insular portion of the ipsilateral claustrum (CII). The distributions of labeled cells confirmed the organization reported in previous studies. In some cases the two labeled cell populations were segregated in different parts of the CII; in other cases there was more or less overlap in the two distributions. The degree of overlap was not simply related to the topographic proximity of the injected cortical territories. In all cases the vast majority of cells were single labeled. In one case both FB and NY were injected in the same cortical area in order to control that claustral axons can retrogradely transport two tracers back to the same parent cell bodies. In this control case CII cells were double labeled. All together these data indicate that widely divergent claustroneocortical projection take origin mainly from separate cells.

Animals↗
PubMed1983

Biological effects of modified colchicines. 2. Evaluation of catecholic colchicines, colchifolines, colchicide, and novel N-acyl- and N-aroyldeacetylcolchicines.

A series of natural and synthetic colchicine derivatives was examined for their potency in the lymphocytic leukemia P388 screen in mice, for their toxicity in mice, and for their binding to microtubule protein. The natural alkaloids cornigerine and colchifoline and several N,O-substituted analogues of colchifoline were found to be as potent and as toxic as colchicine in the P388 screen with good affinity for tubulin. The 1,2-(methylenedioxy)-substituted isomer of cornigerine was considerably less potent in vivo than could have been anticipated from the in vitro tubulin binding data. Several N-acyl and N-aroyl derivatives prepared from deacetylcolchicine showed high potency in the in vitro and in vivo screens. Colchicide was found to be highly potent in vivo, and N-carbethoxydeacetylcolchicine, a synthetic analogue of colchicine with a N-carbethoxy instead of an N-acetyl function, showed interesting biological properties.

Animals↗
PubMed1981

Axonal branches of the same cerebellar neurons terminate bilaterally in the thalamus.

The efferent projections of the deep cerebellar nuclei which terminate bilaterally in the thalamus were investigated in the rat by means of the retrograde fluorescent double-labeling technique. After injection of True Blue or Fast Blue in the thalamus on one side and Nuclear Yellow on the other, the deep cerebellar nuclei on both sides contained many cells single-labeled from the contralateral thalamic injection and some cells double-labeled from both thalamic injections. Double-labeled cells were more numerous in the caudal part of the medial nucleus than in the other cerebellar nuclei. The present results indicate that some cerebellar cells give origin to bilateral thalamic projections by means of axon collaterals.

Animals↗
PubMed1981

The organization of the claustroneocortical projections in the cat studied by means of the HRP retrograde axonal transport.

The projections from the claustrum to the cerebral cortex were examined in the cat by means of horseradish peroxidase (HRP) injections in various different areas of the lateral and medial surfaces of the neocortex. In all cases retrogradely labeled cells were observed in the ipsilateral claustrum insulare (ClI). In most of the cases some labeled cells were also observed in the contralateral ClI. The number of labeled cells was higher following large HRP injections in some cortical areas, such as the motor and visual cortex, than following large HRP injections in other areas, such as the second somatic sensory cortex. The patterns of distribution of labeled cells in the ClI following the different HRP injections evidenced a prevalent anteroposterior and dorsoventral topographical arrangement. However, some degree of overlapping was evident in the distribution of cells retrogradely labeled from injections in different cortical fields. The results of the present study indicate that: a) in all likelihood the claustral projections are distributed upon the entire neocortex; b) they are not uniformly distributed upon the neocortex from the quantitative point of view; c) the arrangement of the claustrocortical projections is predominantly but not strictly topographical. The widespread distribution of the claustral inputs suggests that they must be integrated in different models of cortical activity.

Animals↗
PubMed1981

Effect of ethanol, acetaldehyde, and acetate on insulin and glucagon secretion in the perfused rat pancreas.

The effects of varying concentrations of ethanol (1, 10, and 30 mM) and its metabolites (1 mM acetate and 1 and 10 mM acetaldehyde) on insulin and glucagon secretion induced by glucose (11.1 mM) and arginine (20 mM) were studied in isolated perfused pancreas of Sprague-Dawley rats. Ethanol and its metabolites did not significantly modify basal secretion of the two hormones. Ethanol reduced glucose-induced insulin secretion by means of a dose-related effect. Arginine-induced insulin output did not seem to be influenced to any significant degree. Acetate and acetaldehyde significantly inhibited glucose and arginine-induced insulin secretion. While ethanol (10 and 30 mM ) did not modify glucagon output during arginine perfusion, acetate and acetaldehyde markedly enhanced it. The block of insulin secretion and the increased secretion of glucagon could explain the diabetogenic effect of ethanol demonstrated in vivo. The mechanism by which ethanol acts on the pancreatic beta- and alpha-cells is discussed.

Acetaldehyde↗
PubMed1979

[Surgical treatment of hiatal hernia in adults. Indications, technical and tactical considerations on 310 operated cases].

On the basis of 310 cases of hiatal hernia surgically treated, the anatomical, pathophysiological and clinical aspects are reviewed together with their surgical consequences. In rolling type hernia, gastroesophageal reflux and its sequelae do not occur: the treatment is based only on reduction and suture of the fundus to the undersurface of the diaphragm with repair of right crus. In sliding hiatal hernia the purpose of operation is functional one, that is satisfactory and lasting control of gastro-esophageal reflux. With one exception, the fundamental step of all successful procedures of repair is the creation of restoration of an infradiaphragmatic segment of esophagus: it puts the lower esophageal sphincter into the abdominal cavity with restoration of gastroesophageal competence.

Adult↗
PubMed1979

[Association of idiopathic megaesophagus and carcinoma].

In the light of three cases of esophageal carcinoma developing on a pre-existing idiopathic megaesophagus the authors examine etiopatological, clinical and terapeutic problems related to this association. They believe that carcinoma of the esophagus tends to be a complication of cardiospasm in patients inadequately treated for the primary condition. Early diagnosis and an adequate Heller operation for cardiospasm will lessen the chance of cancer developing in megaesophagus with stasis. When finally diagnosed, this variety of esophageal carcinoma has an extremely poor prognosis. An even more important claim upon the clinician is to be alert to the hazards of continued stasis in megaesophagus and to devise earlier techniques of recognition, including more frequent recourse to biopsy during esophagoscopy.

Aged↗
PubMed1979

[Traumatic hernias of the right hemidiaphragm].

Four cases of right traumatic diaphragmatic hernia are reported. The original aspect of this type of lesion is that herniation of abdominal viscera into the chest is usually delayed due to the liver temporary plugging of the diaphragmatic defect. Diagnostic importance of diaphragm elevation combined with mediastinal push-back is stressed, as well as the value of x-ray examination following pneumoperitoneum. Reduction of the hernia and repair of the diaphragmatic defect can easily be accomplished by abdominal route alone, instead by a transthoracic approach usually preferred by surgeons in delayed presentation, particularly in those patients with marked limitation of pulmonary reserve.

Adult↗
PubMed1975

Human growth hormone and cortisol response to insulin stimulation in aging.

The influence of age on plasma growth hormone (HGH) and cortisol response to i.v. insulin (0.1 U/kg of body weight) was evaluated in 32 healthy subjects whose ages ranged between 20 and 84 years. A significant reduction in HGH response to insulin was observed with aging. In the young (20-34 years), middel-aged (35-49 years), and elderly (53-84 years) groups, average HGH peaks were 46.51 +/- 7.37, 29.95 +/- 5.35, and 14.31 +/- 2.39 ng/ml while average HGH areas were 2.911 +/- 0.484, 1.654 +/- 0.316, and 0.699 +/- 0.149 mug-min, respectively. Since insulin's hypoglycemic effect became less rapid with aging, this could, in part, explain the progressive decline in the HGH response to insulin. This phenomen may also be attributed to histological changes occurring in the pituitary with aging. Moreover, cortisol response was similar to all three age groups. These findings suggest that, while HGH response to insulin is correlated with age, adrenal response does not show any important modifications with aging.

Adult↗
PubMedDate not supplied

Glucagon and insulin secretion in potential diabetes.

Insulin and glucagon have been studied in 20 subjects (both of the subjects' parents were diabetic or in case of only one diabetic parent, the other showed a first degree familiarity of diabetes): 10 showed normal glucose tolerance ('true prediabetics') and 10 impaired glucose tolerance ('genetic chemical diabetes'). Mean insulin response to oral (100 g) and i.v. glucose load (200 mg/kg followed by 20 mg/kg/min for 60 min) and to arginine infusion (25 g in 30 min) was normal in the prediabetics and delayed and higher in the subjects with chemical diabetes as compared to the control group. Glucagon response to arginine was higher, but not significantly, in prediabetics and in subjects with chemical diabetes. In both of these groups glucagon suppression by glucose was not observed. The insulin/glucagon molar ratio was significantly reduced after glucose infusion in these two groups. No correlation was found between insulin and glucagon secretion after arginine or glucose. A possible alteration in the mechanism controlling glucagon secretion even in the earliest phases of diabetes is suggested.

Adult↗