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Biomedical subjects

A Santucci

Publications and source records attributed to A Santucci.

At least 145 records · Page 8Linked to original sources
PubMed1991

Does mild autonomic neuropathy affect atrial natriuretic factor regulation in diabetic hypertensive patients?

The effect of postural changes on plasma atrial natriuretic factor (ANF) levels was investigated in 16 diabetic hypertensives (eight with and eight without mild autonomic neuropathy) and in 10 hypertensives. The presence of renal damage or secondary hypertension was excluded. All diabetic patients were in good metabolic control. In upright position, the mean levels of plasma ANF were of 23.1 +/- 7.6 pg/mL in neuropathic diabetic hypertensives, 24.2 +/- 8.3 pg/mL in diabetic hypertensives, and 21.6 +/- 6.7 in essential hypertensives. Percentage decrease observed after the assumption of supine position was 47 +/- 18, 50 +/- 10, and 46 +/- 13, respectively. No significant difference was found between hypertensives and diabetic hypertensives, even in the presence of mild autonomic neuropathy. Plasma ANF response to postural changes was similar in all groups.

Adult↗
PubMed1991

Plasma insulin levels do not change during atrial natriuretic factor infusion in human essential hypertensives.

In order to evaluate the effects of atrial natriuretic factor (ANF) infusion on plasma insulin (IRI) in hypertension, 32 essential hypertensives (aged 40 to 62 years) were studied. After 1 week of pharmacologic washout under normal sodium intake (120 mEq of Na+/day), patients were randomly assigned to receive either ANF (0.04 micrograms/kg/min) or its vehicle (50 mL of isotonic saline) over a 60-min period in supine position. Plasma IRI and glucose were measured at -60, 0, 20, 40, 60, 120, 180, and 240 min (infusion time: from 0 to 60 min). Plasma levels of IRI and glucose did not change significantly during ANF infusion. On the contrary, after ANF discontinuation plasma IRI rose from levels of 13.5 +/- 6.4 microU/mL at 60 min to values of 20.1 +/- 11.3 microU/mL at 240 min (P less than .0001 v time 0). Plasma glucose showed a similar behavior, increasing from values of 100.4 +/- 5.0 mg/dL at 60 min to values of 120.0 +/- 5.1 mg/dL at 240 min (P less than .02 v time 0). Our findings suggest that ANF did not influence insulin release in hypertensives. The increase of plasma glucose and IRI observed after ANF discontinuation could be due to the relapse of sympathetic activity, suppressed during ANF infusion.

Adult↗
PubMed1991

Three high-lysine mutations control the level of ATP-binding HSP70-like proteins in the maize endosperm.

The synthesis and deposition of seed storage proteins in maize are affected by several dominant and recessive mutants. The effect of three independent mutations, floury-2 (fl2), Defective endosperm-B30 (De-B30), and Mucronate (Mc), that reduce zein level in the endosperm were investigated. These mutations also control the level of b-70, a polypeptide bound to protein bodies, which is separable into the two isoforms b-70I and b-70II by two-dimensional gel electrophoresis. Both isoforms are overexpressed 10-fold in fl2; however, only b-70I is present in De-B30 and Mc, which contain an amount of total b-70 isoforms fivefold higher than in the wild type. Both b-70I and b-70II resemble heat shock protein (HSP70) in that they bind ATP, cross-react with anti-HSP antibodies, and have N-terminal sequence homology to HSP70. All maize protein body-located b-70 characteristics are typical of those of chaperone-like HSPs. A third protein, b-70III, similar in size to but slightly more acidic than b-70I and b-70II, also binds ATP and reacts with the same antibody, providing evidence for the presence in endosperm extracts of a cytosolic chaperone-like protein. The level of b-70III was not altered by the mutations studied. The results suggested that the repression effect of the three mutations on zein accumulation may be mediated by the alteration of a zein transport or zein assembly process involving b-70I and b-70II.

Adenosine Triphosphate↗
PubMed1991

["Slow" fractures of the metatarsi].

On the basis of clinical observation and reports in the literature, the authors discuss the etiology, pathogenesis, and clinical and radiographic aspects of "slow" fractures, with particular reference to those involving the metatarsal. The different etiologic and pathogenetic theories agree upon one point: the concentration of the stresses as a prelude to areas of osteoclastic resorption which lead to microfractures and thus to "slow" fractures. Many factors are responsible for this concentration, and they may very even according to the site of the lesion. In the foot there are many conditions which can potentially explain the pathogenesis of "slow" metatarsal fractures. Overload of the middle metatarsals is one of the most common causes. The overloaded and fractured metatarsal may then become insufficient and in turn, by the same mechanism, cause fracture of the adjacent metatarsals.

Adolescent↗
PubMed1990

HPLC immunoaffinity purification of rabies virus glycoprotein using immobilized antipeptide antibodies.

It has been reported that the acetylcholine receptor may be used by the rabies virus to concentrate at sites in proximal to peripheral nerves. It has also been reported that the binding site for the receptor is located within the 190-203 region of the virus glycoprotein on the basis of its structural homology with the toxic center of snake neurotoxins, which are well known cholinergic ligands. We prepared monoclonal antibodies against the synthetic tetradecapeptide having the same sequence as the putative binding site of the rabies virus. One of three antibodies (clone 2PV 36-74) was able to recognize both the whole virus and its peplomeric glycoprotein and could bind acetylcholine. It was also able to inhibit the binding both of alpha-bungarotoxin and rabies virus glycoprotein to the acetylcholine receptor. We have covalently bound 2PV 36-74 to an HPLC affinity column and utilized it for specific purification of rabies virus glycoprotein. The immunoaffinity chromatographic method we describe is very sensitive and highly specific. Moreover this procedure does not denature the sample and is vary rapid and efficient.

Animals↗
PubMed1990

[Effects of nicardipine in hypertensive patients with chronic kidney insufficiency].

There has been a increasing awareness that calcium antagonists may have beneficial effects on the kidney. Therefore we evaluated the renal and antihypertensive effects of nicardipine treatment in 12 hypertensive patients with chronic renal failure. The drug was given at a dose of 20 mg three times a day. Blood pressure was normalized in almost all cases while the indexes of renal function were improved. A transient deterioration of renal function, probably due to reduction of glomerular capillary pressure was observed in some cases. In conclusion, our data showed a beneficial effect on renal function during nicardipine therapy. This effect could be absent in the most advanced degree of renal damage.

Adult↗
PubMed1990

Neuroendocrine markers in aging brain: clinical and neurobiological significance of dexamethasone suppression test.

The dexamethasone suppression test (DST) is commonly accepted as an indicator of hypothalamus-pituitary-adrenal (HPA) axis functioning in clinical practice. In this study, DST was carried out in a geriatric population composed of patients with dementia of Alzheimer type (DAT), stroke and age-matched controls. The stress state of the subjects was also functionally assessed by the Symptoms Rating Test (SRT). The results disclosed no significant differences in basal cortisol levels in the three groups. A positive correlation between age and log-transformed basal cortisol levels was found in the entire population as well as in each group. After dexamethasone administration, 20% of controls, 49% of DAT patients, and 48% of stroke patients were non-suppressors. At 8.00 a.m. and 11.00 p.m. after dexamethasone, cortisol levels were significantly lower (p less than 0.02) in controls than in pathological groups. A significant positive correlation between age and symptoms of depression and anxiety was found. One-third of stroke patients showing lesions in the right hemisphere were non-suppressors, and presented mostly subcortical infarcts, while 1/4 of them had depressive disorders. This study demonstrated a progressive increase in basal cortisol levels and depressive symptoms with age, a poor diagnostic value of DST in age-related pathological conditions such as DAT and stroke, and the role of these cerebral pathologies in amplifying the neuroendocrine dysregulation due to the ageing process itself. DST is a useful biological marker for disclosing the vulnerability of the ageing brain, but it has no diagnostic value.

Aged↗
PubMed1990

Plasma atrial natriuretic peptide in young normotensive subjects with a family history of hypertension and in young hypertensive patients.

Plasma atrial natriuretic peptide (ANP) behavior was evaluated in 26 untreated essential hypertensives, 21 normotensives, and 20 normotensives with hypertensive heredity under normal sodium intake (120 mEq of Na+/day). All subjects were men, mean age 22.1 +/- 1.9 years. Plasma ANP was evaluated by radioimmunoassay on samples collected in supine position upon waking and again after 1 h of orthostatism. Resulting data showed that ANP in hypertensives (supine = 44.5 +/- 19.4 pg/mL, orthostatism = 24.1 +/- 11.6 pg/mL) was at higher levels than in controls (supine = 38.3 +/- 19.4 pg/mL, orthostatism = 19.9 +/- 10.6 pg/mL) or in normotensives with hypertensive heredity (supine = 42.1 +/- 16.8 pg/mL, orthostatism = 23.2 +/- 10.8 pg/mL). Mean ANP level was higher in the latter group than in the control group (supine = +9%; orthostatism = +14.2%). In conclusion, plasma ANP is raised in young essential hypertensives, resulting in slightly elevated levels in normotensives with hypertensive heredity.

Adult↗
PubMed1990

[Nitrendipine: evaluation of the duration of the antihypertensive effect at different doses using the conventional method and ambulatory monitoring of arterial pressure].

To evaluate the effect-duration of nitrendipine in 20 moderate essential hypertensives (aged from 42 to 66, mean +/- SD: 55 +/- 7) when treated with 20 mg once or twice a day, we utilized the blood pressure standard method of measurement and the ambulatory monitoring. Blood pressure determinations were made during the follow-up at 2- week intervals for 3 months, each measurement being made with a mercury sphygmomanometer, 24 +/- 3 hours after the last dose; laboratory parameters, 2 24-hour blood pressure monitoring (ICR 5200, Spacelabs) and standard ECG were performed at baseline and after 3 months. Following a 2-week run-in period with placebo bid (at 10.00 am and 10.00 pm) a 20 mg morning dose of nitrendipine was started continuing the administration of the placebo tablet at 10.00 pm. The dosage was changed to a twice active daily regimen, with an increase in the daily dose (20 mg twice a day) in those patients whose diastolic blood pressure remained greater than 90 mmHg after a 4-week control. After the twelfth week, another 2-week placebo run-in followed the active treatment. Supine blood pressure recorded after 3-month therapy, showed a significant (p less than 0.0001) reduction in both systolic and diastolic mean values (22/15 mmHg) at the end of active treatment in the 16 patients who ended the trial. In particular, the responders to 20 mg (5 patients) showed a blood pressure reduction of 18 mmHg in comparison with the run-in period; in the other group of responders to increasing dosage of 40 mg (11 patients), we observed a 8 mmHg diastolic blood pressure reduction at 28 days and a successive 7 mmHg at the end of the treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[The modality of endoconnective ossification on cartilaginous substrate: observations on the long bones in the embryo].

The authors conducted a histologic study on the modalities of ossification of the "diaphyseal osseous ferrule" in embryos between the sixth and eighth week of intrauterine life: the ossification of this "diaphyseal osseous ferrule" presents some peculiarities compared to that of other areas: it occurs with the modalities of periosteal ossification, exploiting, however, a cartilagenous substrate. In addition, the authors compared the ossification of the diaphyseal ferrule to that of the "perichondrial ferrule of the layer of ossification", examining histologic sections of embryos in the 25th week of intrauterine life.

Cartilage↗
PubMed1990

[The foot in rheumatoid arthritis].

Because of its high incidence of rheumatoid arthritis, the foot is probably the best place to study this pathology. Timely diagnosis is very important considering the high risk of disability. On the basis of both other studies and first-hand observations, the particular clinical and radiographic characteristics of rheumatoid arthritis of the foot are analyzed, differentiating it from the same disease in other joints. The research and comparison of these particular aspects helped with the overall clinical evaluation of early-diagnosed rheumatoid arthritis, that is before the development of reabsorption phenomena, bone damage, deformities, and ankylosis of the joints of the foot.

Ankylosis↗
PubMed1990

[The effect of iron carrier proteins on the transplantation of H-2 locus-incompatible bone marrow in irradiated mice].

Rabbit bone marrow supernatants were fractionated and purified by Ultrogel and Superose chromatography. A unique fraction promoted engraftment of allogenic bone marrow and enduring hemopoietic chimerism across the histocompatibility (H-2) barrier in lethally irradiated mice. This fraction analysed by reducing SDS-PAGE electrophoresis and transblotted on PVDF membrane or purified by reverse-phase HPLC and SDS-PAGE electrophoresis yielded a main pre-albumin band that was examined for primary structure by Edman degradation. It appeared to be rabbit transferrin. Iron saturated human transferrin, lactotransferrin and egg transferrin (conalbumin) were then tested in irradiated C57B1/6 mice transplanted with bone marrow from histoincompatible BALB/CJ donors. Most mice treated with iron-loaded transferrins survived and developed enduring allogeneic chimerism with no discernible signs of graft-versus-host disease at 10 months posttransplant. Observation of these animals is still carried on. Iron carrier proteins seem to provide a novel unexpected means for achieving a successful engraftment of allogeneic bone marrow in immunologically hostile murine H-2 combinations and may open a new approach in the clinical area.

Animals↗
PubMed1990

Osteoid osteoma of the talus.

The talus is a rare site of predilection for osteoid osteoma. This tumor, in its juxta-articular position, presents particular clinical and pathological features. Three cases of subperiosteal osteoid osteoma are discussed in patients aged 15, 17 and 25 years. In diagnosis, a basic role is played by awareness of the disease, which must lead to the use of bone scan, indicating the site of the pathological lesion, which may be difficult to determine because of subtle radiographic modifications, and particularly because of long-term changes in the symptoms. Radiographic examination (standard x-rays, enlarged x-rays), often characterises and reinforces what is diagnostically suspected. CAT clearly shows the features and type of osteoid osteoma in relation to the adjacent structures. Sequential angioscintigraphy, based on the captation curve of the radionuclide, may suggest the nature of the lesion, subsequently confirmed by the macroscopic picture and histological examination.

Adolescent↗
PubMed1989

The life cycle of a low-molecular-weight protein of surfactant (SP-C) in 3-day-old rabbits.

To clarify the metabolic cycle of a low-molecular-weight protein of surfactant (SP-C), we obtained alveolar surfactant from 3 day old rabbits killed 24 h after the tracheal administration of 32P or L-[35S]methionine (donors). Aliquots of this naturally labelled surfactant were administered into trachea to 3-day-old rabbits (recipients) which were killed after 1 min or 3, 8 or 24 h. We then analyzed the radioactivity associated with SP-C and with saturated phosphatidylcholine in fractions of lung lavage fluid and in lung homogenate. We found that alveolar SP-C is turned over faster than saturated phosphatidylcholine, that alveolar macrophages do participate in the removal of SP-C and that SP-C does not enter the fraction of alveolar surfactant that remains unsedimented after ultracentrifugation. Considering the whole lung, SP-C and saturated phosphatidylcholine are turned over at a comparable speed.

Animals↗
PubMed1989

[Atrial natriuretic factor: an epidemiological study. Preliminary results].

We performed an epidemiological study on the atrial natriuretic factor pattern in a young population. Subjects were recruited in the Ospedale Militare Principale of Rome among young men liable to conscription, whose hospitalization was due either to essential hypertension or to other pathologies (not influencing our study, such as headache etc.). The recruitment lead to the formation of three different groups: normotensives, normotensives with family history of hypertension (mother and/or father) and hypertensives. On the morning of the study (after 7 days of pharmacological wash-out, under a diet containing 120 mEq of Na+/die), blood samples were taken. Plasma atrial natriuretic factor, renin activity and aldosterone were assayed by RIA. Digoxin-like immunoreactive substance was assayed by a solid-phase radioimmunoassay, following the extraction of plasma. Serum creatinine, sodium, potassium and urinary sodium and potassium (24 h before the study) were assayed by standard methods. Urinary kallikrein was assayed by chromogenic substrate S-2266. So far, we have studied 60 subjects (26 hypertensives, 21 normotensives and 13 normotensives with family history) and we wish to discuss in this article the preliminary results concerning the atrial natriuretic factor and its relationship with renin activity, aldosterone and blood pressure. Our results show that the mean plasma levels of atrial natriuretic factor in the hypertensive group were higher, although not significantly, than those of the other two groups and that the normotensives with family history had slightly higher levels as compared to normotensives (Delta % = + 7.4).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗