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Biomedical subjects

V Esposito

Publications and source records attributed to V Esposito.

At least 19 recordsLinked to original sources

Growth rate and growth hormone response to growth hormone-releasing hormone challenge in slowly growing children during chronic administration of clonidine.

In this study the effects of chronic administration of clonidine, an alpha-2-adrenergic agonist, on the growth rate and GH response to GHRH in 12 "slowly growing" children were reported. Clonidine was administered at the dose of 0.04 mg/m2 body surface twice daily along 12 months. The protocol of the study consisted in five periods of growth rate, insulin-like growth factor-1, basal and GHRH-stimulated GH level evaluation: 1) 6-month pretreatment (P1); 2) 6-month placebo administration (PO); 3) after 4 months of therapy (P1); 4) after 4 months of clonidine withdrawal (P2); 5) after 4 months of therapy reinstatement (P3). No difference was observed between P-1 and P0 when all the parameters were considered. During P1 a significant increase of linear growth (p < 0.05 vs P0 and P-1) was observed while standard deviation of height was not modified. At the end of P2, the growth rate and standard deviation of height were similar to those recorded in P0 and P-1. After reinstatement of clonidine therapy a new but less pronounced rise of the growth rate was found (p < 0.05 vs P1, p < 0.01 vs P0 and P-1). GH, insulin-like growth factor-1, GHRH-stimulated GH levels had significantly increased during P1 than P0 and P-1 (p < 0.05), while during P2 they were similar to P0 and P-1. During P3 a new increase of insulin-like growth factor-I baseline and GHRH-stimulated GH levels were observed. However, these were significantly lower than those observed during P1.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Determination by Skeleton

Effects of gonadal steroids on the growth of human pituitary adenomas in vitro.

The effects of testosterone (T), dihydrotestosterone (DHT) and methyltrienolone (R 1881) on cell proliferation of eight human pituitary tumors in culture wre assessed by [3H]thymidine incorporation and compared to those of progesterone (Pg) and 17 beta-estradiol. Receptors for androgens (AR), estrogens (ER) and progesterone (PgR) were characterized. AR had a significant inhibitory effect on all AR-positive tumors, whatever their hormonal content. Inhibitory effects of either T and DHT < R1881 < Pg were observed in tumors co-expressing AR and PgR. The inhibitory effect of R 1881 on a PgR-positive/AR-negative tumor suggested that R 1881 action was partially PgR-mediated. The effects of either T or the nonaromatizable DHT and R 1881 were unrelated to ER expression. We conclude that AR can modulate the growth of human pituitary tumors through direct receptor-mediated intracellular pathways which may be common to various pituitary cell types.

Adenoma

Acute and chronic effects of human recombinant GH (hrGH) on adrenal steroidogenesis in children affected with isolated GH deficiency (IGHD).

In a previous study we demonstrated that, in children affected with isolated GH deficiency, an acute high-dose human recombinant GH (hrGH) treatment increases the 11-deoxycortisol and induces an IGF-I responsiveness to ACTH. The aim of the present study was to reevaluate, in the same children, the adrenal and IGF-I responsiveness to ACTH after a chronic replacement-dose GH therapy. Ten children (seven males and three females, mean age 7 years) affected with isolated GH deficiency underwent a synthetic ACTH 1-17 test before and after sc administration of human recombinant GH at a dose of 0.6 UI/kg/week for 3 months. After therapy, the 11-deoxycortisol responsiveness to ACTH significantly decreased compared with that observed after acute treatment (P < 0.001), and so it returned to baseline. No differences were detected in the responsiveness to ACTH of cortisol, dehydroepiandrosterone-sulphate, D4-androstenedione, and 17-hydroxyprogesterone. On the other hand, the chronic treatment induced an IGF-I responsiveness to ACTH (P < 0.001). In conclusion, our study demonstrates that, in isolated GH deficiency, replacement doses of hrGH do not modify the adrenal steroid basal levels or its responsiveness to ACTH, whereas both replacement and high doses of hrGH induce an IGF-I responsiveness to ACTH.

17-Ketosteroids

Transmaxillosphenoidal approach to tumors invading the medial compartment of the cavernous sinus.

A transmaxillosphenoidal approach was used to remove sellar tumors invading the cavernous sinus. This procedure, a widening of the standard transsphenoidal approach to the sella turcica, uses the sublabial or transnasal route in which the medial wall of the maxillary sinus is laterally dislocated. This method provides good exposure of the prominences of bone above the carotid artery which lies on the posterolateral wall of the sphenoid sinus. This bone area is the key to opening the cavernous sinus inferomedially and removing lesions within its medial compartment. The inferomedial approach takes an entirely extracerebral route so that tumors invading the cavernous sinus through its medial wall are approached inferomedially following the direction of tumor growth. It also allows direct visualization of the intracavernous carotid artery during tumor removal, thus sparing the cranial nerves, which run on the opposite side. Adequate surgical exposure of a pituitary adenoma is achieved with a custom-made sphenoidal retractor with asymmetric blades, the shorter blade holding aside the thin medial wall of the maxillary sinus. Between October, 1989, and July, 1993, 11 patients with tumors invading the cavernous sinus underwent surgery via this approach; 10 had pituitary adenomas and one had a craniopharyngioma. Eight tumors were treated by primary operation: four tumors were totally and four subtotally (> 80%) removed; one tumor already operated on elsewhere was totally removed; and of two tumors already operated on and irradiated, one was subtotally removed and the other only partially (approximately 40%) removed owing to marked postirradiation scarring. None of the patients suffered permanent cranial nerve deficit and all but one showed marked clinical improvement.

Adenoma

[Assessment of dispersion++ of ventricular recovery in patients with chronic obstructive pulmonary disease].

Cardiac arrhythmias are common in patients with chronic obstructive pulmonary disease. Several factors may contribute to the development of arrhythmias in these patients including hypoxemia, hypercapnia, acid-base disturbances. The aim of the study was to assess QTc dispersion in patients with chronic obstructive pulmonary disease, who are at high risk of arrhythmias. Interlead QT variability as measured on the 12-lead electrocardiogram is not a technical artifact but probably reflects regional differences in ventricular repolarization. Increased dispersion of ventricular recovery time is believed to provide a substrate which supports serious ventricular arrhythmias. We showed that in patients with chronic obstructive pulmonary disease, free of underlying structural heart disease, the QTc dispersion is significant greater (p = 0.036) than in a control group, despite a similar value in mean QTc value. The data of the present study suggest that the determination of dispersion of repolarization times may be affected by metabolic changes occurring in patients with chronic obstructive pulmonary disease.

Adult

The supine position for transsphenoidal surgery.

The supine position has been routinely used for transphenoidal microsurgery in our department since 1973. We had 404 patients, 387 of whom had pituitary micro-or macroadenomas. It is always satisfactory, allowing a very good control of intraoperative arterial pressure and prevention of air embolism. It is also comfortable for both surgeons.

Adenoma

Extrahypothalamic distribution of vasoactive intestinal polypeptide (VIP)-like immunoreactivity in the chicken brain, Gallus domesticus.

The distribution of VIP-immunoreactive neurons and fibers was detected in the extrahypothalamic areas of chicken brain by immunohistochemistry and light microscopy VIP-ir perikarya were found in the hippocampus and in the area parahippocampalis; in the area ventralis of Tsai, in the n. interpeduncularis, in the substantia nigra, in the substantia grisea centralis, in the locus coeruleus, in the n. subcoeruleus ventralis and in the n. pontis lateralis. VIP-ir fibers were seen in the lobus parolfactorius and throughout the brainstem mainly arranged in lateral and midsagittal position. This finding was discussed in relation to other studies performed on chicken and/or other avian brain. The distributional pattern of VIP-ergic system in the chicken brain suggests a possible involvement of VIP or VIP-like peptide in several neuroregulatory mechanisms.

Animals

A simple method for stereotactic microsurgical excision of small, deep-seated cavernous angiomas.

Eight patients underwent microsurgical excision of small, deep-seated cavernous angiomas (maximum diameter, 0.9 to 2 cm; distance from cortical surface, 3.5 to 6.5 cm) by the stereotactic implantation of a guide catheter. In all cases, the lesion was quickly localized and completely removed. None of the patients had postoperative neurological deficits. Once the guide catheter has been implanted, the stereotactic headframe can be removed, allowing the unobstructed use of the operating microscope with frames not suitable for open surgery. Target localization is not affected by brain movement, which is inevitable during open surgery. The procedure described here is simple to perform and relatively inexpensive. It requires no specially designed equipment, only a standard stereotactic apparatus, an operating microscope, and the usual microsurgical instruments.

Adult

Predictors of perinatal outcome in intrauterine growth retardation: a long term study.

UNLABELLED: Fifty-three intrauterine retarded fetuses (IUGR) and seventy-five healthy pregnancies were monitored by neurobehavioural profile (quiet state or S1F and activity state or S2F percentages) and umbilical artery Doppler velocimetry (UA RI) on two occasions between the 27th-32nd and the 33rd-36th week of gestation. The aims of the present study were the following 1) to relate S1F, S2F and RI to mild and severe IUGR 2) to relate behavioural state analysis and UA Doppler velocimetry to the following perinatal outcomes: Cesarean section (CS); Preterm delivery (PD); small for gestational age (SGA); Apgar score at 1st and 5th min < 7; Respiratory Distress Syndrome (RDS); Neurological Injury (NI) (evaluated at the birth, the 4th, the 8th and the 12th month of life). 3) to establish the best predictors of perinatal outcome with these monitoring parameters by a stepwise computerized processing. Our results suggest: 1) mild IUGR, characterized by a progressive increase in peripheral vascular resistances, positive diastolic peak flow (RI: 0.72 +/- 0.01; mean +/- SD), is associated with gradual increase in S1F (12.51 +/- 2.84; mean +/- SD) and a decrease in S2F (27.51 +/- 2.81; mean +/- SD) percentages; 2) severe IUGR, characterized by zero or negative diastolic peak flow (UA RI-->1), is associated with a significant increase in S1F (21.32 +/- 12.11; mean +/- SD) and a decrease in S2F percentages (30.93 +/- 20.35; mean +/- SD). IN CONCLUSION: S1F is the best predictor of severe IUGR and significant for all the perinatal outcomes selected; S2F is the best predictor of mild IUGR and significant for SGA; UA RI is the best parameter for recognizing mild IUGR and evolution to severe IUGR.

Behavior

[Benign insulinoma. Efficacy of preoperative treatment for persistent hyperinsulinemia using a synthetic somatostatin analog].

We investigated the 24-hour mean blood glucose and serum insulin (IRI), C peptide (C pep) and glucagon concentrations before (pre) and after (post) continued treatment with octreotide (100 mcg three time daily by s.c. injection) in a woman, 68 years old, affected by a nine years long benign insulinoma. The blood pool to dose 24-hour mean glucose and all hormone concentrations was obtained by equal quantities of blood samples taken every 2-hour over 24-hour. The IRI, C pep, glucagon, glucose circadian pattern and IRI/glucose ratio were determined on remaining blood portions. After continued treatment with octreotide was significantly reduced the exaggerated and inappropriate insulin (pre = 77.08 +/- 23.6 microUI/ml; post = 15.19 +/- 2.3 microUI/ml; p < 0.001) and C pep secretion (pre = 4.17 +/- 0.4 ng/ml; post--1.64 +/- 0.04; p < 0.001), while the blood glucose levels were significantly elevated (pre = 40.46 +/- 3.1 mg/dl; post = 132.46 +/- 6.9 mg/dl; p < 0.001). Also glucagon levels were significantly inhibited (pre = 73.53 +/- 12.19 pg/ml; post = 46.80 +/- 9.1 pg/ml; p < 0.05). The long-acting somatostatin analogue has improved a lot IRI/glucose ratio (pre = 1.9 +/- 0.4; post = 0.12 +/- 0.04; p < 0.001). A significant positive correlation was found between IRI and C pep before (r = 0.93; p < 0.001) as well after octreotide treatment (r = 0.85; p < 0.001). A significant positive correlation (r = 0.69; p < 0.008) between IRI and glucose was observed only after octreotide treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged

Simultaneous and bilateral inferior petrosal sinus sampling for the diagnosis of Cushing's syndrome: comparison of multihormonal assay, baseline multiple sampling and ACTH-releasing hormone test.

In 29 consecutive patients with adrenocorticotropin (ACTH)-dependent Cushing's syndrome, we compared the usefulness of multiple baseline ACTH evaluations (10/29), multiple hormone evaluation (29/29) and ACTH-releasing hormone (CRH) stimulation (21/29) during simultaneous and bilateral inferior petrosal sinus sampling. The basal inferior petrosal sinus/periphery ratio for ACTH concentrations was greater than 2 in 18 of the 29 patients and CRH challenge caused the appearance of an inferior petrosal sinus/periphery ratio greater than 3 in 6 other patients. The presence of an ACTH-secreting adenoma was surgically proven in all the 24 patients who had an ACTH inferior petrosal sinus/periphery ratio greater than 2 basally or greater than 3 after the CRH test but also in 1 patient who had an inferior petrosal sinus/periphery ratio lower than 2 basally or 3 after the CRH test. In 4 patients, both the very high peripheral ACTH levels, the inferior petrosal sinus/periphery ratio and the complete lack of ACTH increase after CRH indicated the presence of an ectopic ACTH syndrome: a bronchial carcinoid was found in 2 patients, whereas the site of the tumor is still unknown in the remaining 2. An ACTH intersinus gradient greater than 1.4 was found in 23 patients. Among these 23 patients, the side of the adenoma was correctly predicted in 19 patients and wrongly in 4.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

Neuromuscular effects of temporomandibular joint dysfunction.

Neurologically intact male and female TMJ dysfunction patients with or without cervical spine involvement were examined using standard clinical neurologic testing for balance and coordination. Seventy percent of the TMJ patients without cervical involvement exhibited positive signs for balance, coordination, and/or ataxia found in response to having the patient's mandible stressed by extending it as far as possible laterally, and also opened (as wide as possible) or closed (biting down). The performance of patients with cervical involvement was not significantly different than those without cervical involvement. Further examination of the relation between the TMJ and auditory, visual, cerebellar, and coordination mechanisms is therefore indicated.

Adult

Ultrastructural observations on cytotoxic effector cells infiltrating pancreatic islets of low-dose streptozocin treated mice.

The aim of this study was to observe the ultrastructural events, during the onset of diabetes mellitus in the low-dose streptozocin (LDS)-treated mouse model with emphasis on the infiltrating elements. Forty male C57 BL/6J mice were given 40 mg/streptozocin on 5 consecutive days and killed 5, 6, 7, 8, 9, 10, 15, and 18 days after the first injection. Results demonstrated that islet infiltration occurring in LDS-treated mice is characterized by a very early pre-infiltration state in which mononuclear phagocytes in islet capillary vessels were considerably increased in number. A new histopathological time sequence for the early insulitis is described, in which attraction of blood mononuclear phagocytes into the islet capillary lumen is the first step. During the successive stage, occurring on days 6-8 we observed that mononuclear phagocytes migrate through capillary and venule walls into the islet parenchyma, where they differentiate into tissue macrophages. It was only later (step 3) that these macrophages acquired novel properties, typical of their "activated state" and started to phagocytose islet beta-cell debris. These data suggest that during the pre-infiltration and early insulitis the mononuclear phagocyte system plays a key role in the onset of LDS diabetes.

Animals

Extrahepatic portal vein aneurysm: report of a case treated by thrombectomy and aneurysmorrhaphy.

Extrahepatic portal vein aneurysm is a rare condition with only 15 cases before ours being reported in the English literature. The etiology is thought to be congenital, secondary to portal hypertension or associated with abnormal weakness of the vein wall. It often presents in conjunction with major gastrointestinal bleeding, but may occur with minimal or no symptoms. Diagnosis is made with color duplex ultrasound, computed tomographic scan, venous phase mesenteric angiography, magnetic resonance imaging, or splenoportography. Thrombosis, rupture, and pressure effects are the major complications of portal vein aneurysm. Shunting procedures are recommended in cases with portal hypertension secondary to liver disease. We report the first case treated by thrombectomy and aneurysmorrhaphy with a successful 10 year follow-up. This procedure should be considered to preserve portal vein flow when portal hypertension is absent or is secondary to the aneurysm itself.

Adult

Further evaluation of IGF-I responsiveness to ACTH in children affected with IGHD.

In our previous studies we had demonstrated that, in children affected with isolated GH deficiency (IGHD), a short-term recombinant growth hormone (rGH) therapy increases the 11-deoxycortisol (S) secretion and induces an IGF-I responsiveness to the ACTH challenge. The aim of the present study was to further investigate the mechanisms by which IGF-I is secreted after ACTH challenge in children affected with IGHD by correlating IGF-I versus cortisol (F) time courses after ACTH administration. Ten children affected with IGHD were subjected to rGH therapy (4 IU/day subcutaneously) for 10 days. The responsiveness of IGF-I, F and S to the ACTH 1-17 test were evaluated before and at the end of the therapy. No IGF-I response to the ACTH test was recorded in the patients before the rGH treatment, whereas after rGH administration ACTH induced a significant IGF-I release (p < 0.001) which started at the 1st hour, reached a peak value between the 5th and 6th hours and disappeared at the 10th hour. In conclusion, our study confirms that a short-term rGH therapy induces an IGF-I responsiveness to ACTH and helps to better define the kinetics and the mechanism of this IGF-I response to ACTH.

Adrenocorticotropic Hormone