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S Valenti

Publications and source records attributed to S Valenti.

At least 19 recordsLinked to original sources
PubMed1999

Melatonin influences interleukin-12 and nitric oxide production by primary cultures of rheumatoid synovial macrophages and THP-1 cells.

Because some of the clinical symptoms related to rheumatoid arthritis (RA) synovitis, such as joint morning stiffness and gelling, might be related to the effects exerted by the diurnal rhythmicity of the neurohormone melatonin (MLT) on synovial immune cell activation, we decided to evaluate the influence of MLT on the production of IL-12 and nitric oxide (NO) on primary cultures of RA synovial macrophages. Synovial macrophages were also prestimulated with lipopolysaccaride (LPS). Results were compared with those obtained on cultured human myeloid monocytic cells (THP-1). A significant increase in IL-12 (p = 0.01) was found in media of MLT-stimulated synovial macrophages versus RMPI-treated synovial macrophage controls. Interestingly, a significant decrease of IL-12 (p < 0.0001) was observed in media of synovial macrophages previously activated with LPS and then treated with MLT, when compared to synovial macrophages treated with LPS alone. A significant increase in NO levels (p = 0.01) was found in MLT-stimulated synovial macrophages versus RMPI-treated synovial macrophage controls. Interestingly, a nonsignificant increase of NO levels was observed in media of synovial macrophages previously activated with LPS and then treated with MLT, when compared to cynovial macrophages treated with LPS alone. Finally, a significant increase in IL-12 (p = 0.03) and NO (p = 0.002) concentrations was observed in media of MLT-stimulated THP-1 cells versus RMPI-treated controls. Our results therefore show that MLT induces IL-12 secretion and NO production by unstimulated cultured RA synovial macrophages and human monocytic myeloid THP-1 cells. The unexpected and opposite effects on IL-12 and NO production in RA synovial macrophages treated with LPS may be related to dose-dependent mechanisms exerted by MLT or to altered cell priming in RA macrophages; these are matters of our further research. This study strongly supports the role of MLT in immune response modulation and in particular suggests a close relationship between diurnal rhythmicity of neuroendocrine pathways, cytokine and reactive oxygen intermediate production by monocyte/macrophages, and synovial arthritis symptomatology, at least in RA.

Adult↗
PubMed1999

Serum leptin levels in males with delayed puberty during short-term pulsatile GnRH administration.

Leptin may be a possible trigger for puberty. In normal males, it has been shown that leptin increases from the pre-pubertal to the early pubertal stage, and then declines in the late pubertal stage. We examined leptin levels in six male adolescents (mean age 16.3+/-0.6 yr; range 14.2-17.6 yr) with delayed puberty (constitutional delay of puberty no.=2; idiopathic hypogonadotropic hypogonadism no.=4) during 120 days of subcutaneous pulsatile GnRH administration. A group of subjects in pre-puberty (no.=11), early-puberty (n=10) and mid-puberty (no.=7) were evaluated as controls. Morning blood samples were taken for determination of leptin, testosterone, LH and FSH levels. In delayed puberty subjects blood samples were taken every 30 days after the start of GnRH administration. At each examination BMI and testicular volume were evaluated. A follow-up examination was performed in the 6 patients 1.3-7.5 yr after the end of the 120 days of GnRH therapy. At baseline evaluation in delayed puberty mean leptin levels were 11.3+/-2.0 microg/l (median 11.3 microg/l; range 4.7-17.3 microg/l) and were higher than those found in pre-puberty (p=0.04) and mid-puberty (p=0.001). During GnRH administration there was no change in BMI and leptin levels but there was an increase in gonadotrophin levels, testosterone and testicular volume. One hundred and twenty days after, mean serum leptin were 10.1+/-2.1 microg/l (median 9.1 microg/l; range 3.4-16.8 microg/l). At the end of the study, leptin levels were higher in delayed puberty than in mid-puberty (p=0.002). At the follow-up examination leptin levels were 4.3+/-1.3 microg/l (median 3.4 microg/l; range 1.4-9.1 microg/l) (p=0.03 vs end of 120 days GnRH therapy) while testosterone and BMI were not changed. In conclusion 120-day pulsatile GnRH administration induced in males with delayed puberty physiological-like pubertal changes but not the decline in leptin levels reported during the progression of puberty. Therefore, in males with delayed puberty an impairment in the phenomenon of leptin decline associated with progression of puberty could be suggested. However after retrospective diagnosis of pubertal delay and long-term therapy in subjects with idiopathic hypogonadotropic hypogonadism leptin levels declined. These data seem to indicate that time more than increase in testosterone levels and testicular volume is the determinant of leptin decline at puberty.

Adolescent↗
PubMed1999

Biphasic effect of nitric oxide on testosterone and cyclic GMP production by purified rat Leydig cells cultured in vitro.

Nitric oxide (NO) biphasically modulates osteoclast function and sperm motility by exerting a positive effect at low concentrations and a negative effect at high concentrations. We therefore tested whether NO exerts a comparable effect on testosterone secretion by cultured rat Leydig cells. Three NO-donors, S-nitroso-N-acetylpenicillamine (SNAP), diethylamine/nitric oxide complex sodium salt (DEA/NO) and diethylenetriamine nitric oxide adduct (DETA/NO) were administered in a wide range of concentrations (10(-8)-10(-3) M for 3 h) to Percoll-purified Leydig cells from adult rats. These drugs raised testosterone and cGMP secretion when used at low concentrations (10(-8)-10(-5) M); however, they inhibited testosterone, but did not affect cGMP, secretion at concentrations higher than 10(-5) M. Administration of the NO scavenger haemoglobin (160 micrograms/mL) prevented both the stimulatory and the inhibitory effect of these drugs. Nitrite accumulation was measured as a marker of NO released by the drugs in our in vitro system; it fell within the range of control media in the presence of NO-donor concentrations lower than 10(-5) M, but was several-fold higher in the media of cells treated with concentrations of the NO-donors greater than 10(-5) M. These data show that (1) NO exerts a biphasic effect on testosterone secretion, which is stimulatory at low and inhibitory at high concentrations; (2) the stimulatory effect of NO is mediated by cGMP, the classic second messenger for NO action.

Adult↗
PubMed1999

[Gonadotropin response to GnRH and seminal parameters in low grade varicocele].

The pathogenetic role of varicocele in male infertility is still controversial. Although epidemiological data have clearly shown a higher incidence of varicocele in the population of subfertile and infertile patients, the real effectiveness of the surgical repair of varicocele, expressed as increase in the pregnancy rate, is still debated. The presurgical gonadotropin releasing hormone (GnRH) test is the most reliable predictive index of successful surgical outcome in terms of fertility. Only patients with an increased gonadotropin response (in particular FSH) to GnRH will benefit from the surgery. The aim of the present study was to evaluate the gonadotropin response to GnRH 50 micrograms i.v. in a group of patients with low-medium grade varicocele. At the beginning of the test, a fine needle was inserted into the forearm and kept patent by a saline solution. Blood samples were collected at the following experimental times: 0, +15, +30, +60, +90, +120 min. The stimulus was administered i.v. as bolus at time 0. The gonadotropin response to the stimulus and baseline levels of testosterone, PRL, 17 beta oestradiol and SHBG were compared with those of a control group. Moreover, all the patients underwent semen analysis after 3-7 days' abstinence and to ultrasound-doppler of the testis. Finally, we preliminarily looked for the presence of microdeletions on the Yq chromosome by polymerase chain reaction. No difference in baseline hormonal levels was found between the patients with varicocele and the controls; the LH response to GnRH was also similar in the two groups. The patients with varicocele showed a significantly (p = 0.03) higher FSH response (13.6 +/- 5.9 mUI/ml) to GnRH than controls (3.8 +/- 0.5 mUI/ml). A significant positive correlation (r = 0.6, p = 0.05) was found between LH peaks after GnRH testing and varicocele grade. Nine of 11 patients with varicocele showed significant seminal abnormalities (i.e., oligoasthenospermia): all patients showed a normal karyotype and no microdeletions were detected on the Yq chromosome. The authors underline the importance of presurgical GnRH testing in patients with low grade varicocele, given the close correlation between gonadotropin-stimulated peaks and varicocele grade found in the study. The presence of significant seminal abnormalities, even in patients with low grade varicocele, suggests the use of molecular genetic techniques to detect possible microdeletions on the Yq chromosome, which may be responsible for the infertility.

Adolescent↗
PubMed1999

[An increased prevalence of thyroid echographic and autoimmune changes in hyperprolactinemic women on therapy with dopaminergic drugs].

Prolactin (PRL) possesses mitogenic and immunomodulatory properties. We evaluated the prevalence of ultrasonographic thyroid alterations and thyroid autoimmunity in hyperprolactinaemic (HPRL) women and correlated these with PRL levels. Furthermore, we studied the PRL binding in human benign nodular thyroid tissues. 133 HPRL patients (16-63 years) and 103 healthy female controls (16-63 years) with no known history of thyroid disease were studied. Blood samples were collected for PRL, FT3, FT4, TSH, thyroid peroxidase auto-antibodies (TPO Ab) and thyroglobulin auto-antibodies (Tg Ab) assays. All subjects underwent thyroid ultrasonography. PRL binding to thyroid membranes was determined by in-vitro radioreceptor assay in 5 human benign nodular thyroid fragments obtained from female patients. No difference in TSH levels was found, while FT3 (4.5 +/- 0.1 pmol/L) and FT4 (16.2 +/- 0.4 pmol/L) levels were significantly higher in controls than in HPRL (FT3: 3.8 +/- 0.1 pmol/L, p = 0.01, FT4: 15.4 +/- 0.2 pmol/L, p = 0.04). The prevalence of thyroid ultrasonographic alterations (simple goitre, uni-multinodular goitre, chronic thyroiditis) was significantly higher in HPRL (30.8%) than in controls (15.5%, p = 0.01) but did not correlate with mean initial and actual PRL levels or duration of the disease. The prevalence of autoantibodies was significantly higher in HPRL (29.6%) than in controls (14.3%, p = 0.04) but did not correlate with PRL levels. Very low specific PRL binding to thyroid membranes was detected. The high prevalence of thyroid ultrasonographic alterations and autoimmunity in HPRL suggests a possible role of PRL in the development of thyroid diseases. Clinical and instrumental thyroid screening may therefore be advisable in these patients.

Adolescent↗
PubMed1997

LH isoform profiles during short-term pulsatile LHRH administration in elderly men.

LH isoform profiles were analyzed in sera resolved with isoelectrofocusing from 5 elderly men (age 70.6 +/- 2.95) and 5 young adult men (age 28.2 +/- 1.24), by using polyclonal antibodies (RIA), monoclonal antibodies directed against the beta-subunits (IRMA) and in vitro LH bioassay. Despite the fact that the elderly had lower testosterone levels than the young (293 +/- 38 vs 512 +/- 77 ng/dl, p < 0.05), no differences were noted in the isoforms detected by any of the assays, although each assay yielded a characteristic profile. Indeed, RIA showed most LH in the acidic range, while IRMA revealed LH profiles with a major peak in the basic range, thus resembling the profiles determined by means of the bioassay. In the elderly, the profiles were also analyzed on day 7 and day 14 of short-term pulsatile sc LHRH administration (150 ng/bw/120 min). Only the LH bioassay detected an LHRH-induced shift to more basic and bioactive forms; these changes accompanied an increased in testosterone levels on day 7 (396 +/- 83 ng/dl, p < 0.05 vs day 0) and on day 14 (320 +/- 58 ng/dl NS vs day 0). Our data suggest that: 1) the profiles obtained in young and elderly subjects are similar, irrespective of the antisera used; 2) as a result of treatment with LHRH in the elderly an increase in T levels occurs, possibly due to the observed changes in LH bioactivity; 3) the in vitro LH bioassay appears to be the most sensitive assay in detecting such changes, which consisted of an enrichment in more basic and bioactive glycoforms.

Adult↗
PubMed1997

Hexarelin is a stronger GH-releasing peptide than GHRH in normal cycling women but not in anorexia nervosa.

Anorexia nervosa (AN) is a chronic disease in which an enhanced GH response to GHRH, a paradoxic increase after TRH and LHRH, and low IGF1 levels may be present according to the patient's clinical state. It is well known that the GH hypersecretory state commonly found in the "acute phase" of AN is restored with weight gain. The new synthetic hexapeptide, Hexarelin (HEX), which is chemically similar to GH-releasing peptide 6, has recently been shown to possess a stronger GH-releasing activity than GHRH in humans and to share a synergistic effect with GHRH when administered intravenously. Indeed, HEX shows a slight cortisol and PRL-releasing activity. The aim of the study was to evaluate the effect of i.v. administration of old (GHRH) and new (HEX) GH-releasing peptides on GH, PRL and cortisol secretion in 9 AN patients in the "recovery phase" of the disease, after partial but significant weight gain. For controls we studied 7 normal cycling women. No significant difference in GH secretion after GHRH was found between AN and controls. GHRH was not able to release cortisol or PRL either in AN or controls. HEX produced a significantly (p < 0.05) higher GH peak in controls than in AN, while GH AUC was slightly but not significantly higher. Indeed, only in controls, HEX was a stronger GH-releasing peptide than GHRH. These findings could be explained by the fact that, in AN, GH secretion is already stimulated both by reduced IGF1 levels and by increased GHRH/somatostatin ratio. As reported in the literature, the action of HEX action is only slightly influenced by variations in somatostatin tone. It therefore appears likely that the absolute or relative GHRH increase present in AN could partially mimic the unknown hypothalamic factor necessary for HEX action on the hypophisis and that, following a structural modification of pituitary HEX receptors, GHRH would become able to bind to HEX receptors on somatotropic cells. Consequently, the pituitary cells would already be over-activated and so unable to respond maximally to HEX stimulation. Indeed, in AN, GHRH might play a role of negative modulation in the control of HEX action. Finally, in our study HEX was able to produce a persistent PRL release in controls but not in AN, thus suggesting that its action could be partially dependent on the estrogen milieu, while it stimulated cortisol secretion only transiently in the patients studied.

Adolescent↗
PubMed1997

Prolactin decrease and shift to a normal-like isoform profile during treatment with quinagolide in a patient affected by an invasive prolactinoma.

Prolactin (PRL) circulates as multiple molecular weight variants: glycosylated phosphorylated, deamidated and sulphated forms. The profiles of the forms, as determined by isoelectrofocusing (IEF), differ in physiological and pathological conditions. The case of a 72-year-old woman affected by an invasive prolactinoma is described. The patient had undergone surgical treatment followed by radiotherapy at the age of 71 years. Bromocriptine therapy followed (up to 10 mg/die), but the PRL levels were still extremely high (over 13,000 micrograms/l as determined by IRMA, after dilution). We therefore treated the patient with quinagolide, at increasing dosages, from 150 micrograms/die on day 0 to 600 micrograms/die on day 220. This treatment progressively lowered PRL to 23.2 micrograms/l. In addition to a decrease in PRL levels, a progressive change in the IEF profile was also noted. Indeed, on day 0, the PRL isoforms were very acidic and during treatment they progressively shifted toward a more basic range. For purpose of comparison PRL profiles were also determined in 8 women with pathological hyperprolactinaemia (group A, aged 16-50 years, PRL levels: 25.1-170.4 micrograms/l), in 6 normal women (group B, aged 25-29 years, PRL levels: 3.4-7.9 micrograms/l) and in 5 normal women during a TRH test (group C, aged 17-52 years, PRL levels: 2.7-10.3 micrograms/l). The profiles observed in group A had a single major peak at isoelectric point (pI) 6.5, while the group B and C profiles were more heterogeneous displaying multiple minor peaks, the majority of the molecules being in a more basic range (pI 6.9 for group B and pI 7.5 for group C). During treatment, the profiles of our subject at first resembled those of group A; subsequently, when the PRL levels had normalised, the profile resembled those noted in group B. Altered (immature?, more glycosilated?, less bioactive?) PRL molecules could be secreted by the tumour. These data show that quinagolide successfully reduced PRL levels, while inducing secretion of forms more similar to those found in women affected by pathological hyperprolactinaemia or in normal women.

Adolescent↗
PubMed1997

Immunoreactive endothelin in nodular pathology of the thyroid.

OBJECTIVES: Endothelins (ETs) can act as autocrine and/or paracrine regulators of thyroid homeostasis and growth. The aim of this study was to evaluate immunoreactive ET (i-ET) levels in a group of patients with nodular pathology of the thyroid and to correlate them with the cytomorphological features after fine-needle aspiration (FNA) and with hormonal and immunological status and blood pressure levels. DESIGN: Plasma and cystic i-ET were assayed in a group of patients with varying thyroid function, who underwent FNA for solid and cystic nodular pathology. PATIENTS: 47 patients (32-81 years) with nodular pathology of the thyroid and 18 controls (28-70 years) with normal thyroid function and morphology were studied. MEASUREMENTS: Fasting venous blood samples were collected and the plasma for i-ET was frozen at -80 degrees C until assayed. Sera were frozen at -20 degrees C for FT3, FT4, TSH, TPO autoantibodies and thyroglobulin autoantibodies assay. Cystic fluid was obtained by FNA, centrifuged, and the supernatant was stored at -20 degrees C until i-ET assay. FNA cytology was examined by light microscopy. RESULTS: In patients with cystic nodules, plasma i-ET levels were significantly (P = 0.002) higher (5.7 +/- 1.1 ng/l, +/- SEM) than in both patients with solid nodules (2.6 +/- 0.4 ng/l) and (P = 0.02) controls (3.0 +/- 0.3 ng/l). In patients with cystic nodules, cystic i-ET levels (12.6 +/- 1.9 ng/l) were significantly (P = 0.003) higher than plasma levels (5.7 +/- 1.1 ng/l) and did not correlate with the percentage of FNA cellularity. i-ET levels in cystic fluid (12.6 +/- 1.9 ng/l) were significantly (P = 0.0001) higher than plasma i-ET levels in both patients with solid nodules and controls. No difference in either plasma or cystic i-ET levels was found in patients with cystic nodules in relation to differences in thyroid function. No difference in plasma i-ET levels was found between patients with solid nodules and controls. In controls, no significant difference in plasma i-ET levels was found between males and females. A negative correlation (r = -0.55, P = 0.02) was found between cystic i-ET levels and systolic and diastolic blood pressure. No correlation between cystic or plasma i-ET levels and FT3, FT4 or TSH was found in any of the subjects studied. CONCLUSIONS: It seems that endothelins do not possess a primary role in determining thyroid function and that the increased levels in cystic fluid found in our subjects could be secondary to cystic nodule development.

Adult↗
PubMed1997

Nitric oxide modulates in vivo and in vitro growth hormone release in acromegaly.

Nitric oxide (NO) has recently been shown to modulate pituitary secretion both in vivo and in vitro. The aim of this study was to investigate the effects of this chemical transmitter on spontaneous and growth-hormone-releasing hormone (GHRH)-induced growth hormone (GH) secretion in acromegalic patients, as well as from GH-secreting tumors maintained in vitro. The study was carried out in 7 acromegalic patients (46.2 +/- 2 years) and in 5 normal subjects (40.1 +/- 1.5 years). GH and prolactin (PRL) secretion were assayed during the administration of isosorbide dinitrate (ID, 5 mg, orally), an NO donor, GHRH, and ID plus GHRH. During ID, a significant (p < 0.05) increase (37%) over basal GH levels was only observed in acromegalics. There was no change in GH levels in response to GHRH or ID plus GHRH in either group. No significant change in PRL levels was observed in either group during ID, while GHRH, with or without ID, induced a slight increase in PRL levels in acromegalics only. Tumor specimens were obtained by selective transsphenoidal adenomectomy, and the cells were plated and incubated for 1, 2 and 24 h in the presence of sodium nitroprusside, a releaser of NO (SNP, 0.3 or 0.6 mM), of GHRH (10-8 M) or of both. SNP significantly (p < 0.001) increased GH levels in a dose-dependent manner (R = 0.99, p = 0.02), but was unable to modify the GH response to GHRH. In acromegalics, a significant correlation (R = 0.822, p < 0.045) and a correlation near the limit of significance (R = 0.73, NS) were observed respectively between the in vivo GH response to ID and the in vitro response to SNP at 24 h. No significant effect was observed on PRL secretion during SNP incubations, while GHRH produced a significant increase in PRL after 2 and 24 h incubation in acromegalics. These observations indicate that NO plays a stimulatory role in vivo and in vitro on GH secretion in acromegalic patients.

Acromegaly↗
PubMed1997

Melatonin receptors are present in adult rat Leydig cells and are coupled through a pertussis toxin-sensitive G-protein.

Previous studies have suggested that melatonin (MLT) acts directly on rat Leydig cells by modulating androgen production. In the present study, the site of action of MLT was investigated. The binding of 2-[125I]iodomelatonin (125I-MLT; 7-240 pmol/l) to Leydig cell membrane fragments was tested in the presence or absence of guanosine 5'-O-(3-thiotriphosphate) (GTP-gamma-S; 50 mumol/l). Saturation studies and Scatchard analysis revealed the existence of a high-affinity binding site with a Bmax of 46.70 +/- 3.50 fmol/mg protein and a Kd of 88.70 +/- 6.20 pmol/l; treatment with GTP-gamma-S reduced the concentration of 125I-MLT binding sites (Bmax 34.03 +/- 4.50), while increasing the Kd to 106.5 +/- 2.61 pmol/l. Pretreatment of the cells with pertussis toxin (PTX; 10 ng/ml for 16 h) resulted in a decreased binding of 125I-MLT and a lack of effect of GTP-gamma-S. Moreover, the effect of MLT on testosterone secretion induced by LH (30 mIU/ml), forskolin (1 mumol/l) and LHRH (100 nmol/l) was studied after 3-h incubation of cells which had been precultured with or without PTX. The inhibition of testosterone secretion due to MLT administration was eliminated by PTX pretreatment during forskolin and LH, but not during LHRH administration. However, 17-hydroxyprogesterone levels were higher in all groups incubated in the presence of MLT, irrespective of PTX pretreatment. Our data suggest that: (a) MLT receptors are present on the membranes of adult rat Leydig cells; (b) they couple through PTX-sensitive G-protein-coupled binding sites; (c) the mechanism by which MLT blocks 17-20 desmolase enzymatic activity (thus leading to increased 17-hydroxyprogesterone levels), and testosterone secretion during LHRH stimulation is likely to depend on one or more different mechanism(s) of action.

Animals↗
PubMed1997

Effects of sumatriptan on growth hormone releasing hormone-stimulated growth hormone secretion in acromegaly.

Sumatriptan (SU), a specific 5-HT1D receptor agonist, was recently shown to be able to increase growth hormone (GH) levels in normals, but not in acromegalics, while no effect was seen on prolactine (PRL). SU is also able to produce an increase in GH response to growth hormone releasing hormone (GHRH) in prepubertal children. In this study we investigated whether SU administration influences GHRH-induced GH secretion in 8 acromegalics, and 6 age-matched normal volunteers, as a control group. We evaluated the effects of SU (6 mg s.c.) or placebo (PL) administration on GHRH (1 microgram/kg bw i.v.)-induced GH and PRL secretion. After SU priming the GH response to GHRH did not changed in acromegalics, but significantly decreased in controls, in comparison with that observed after PL plus GHRH. In acromegalics, no difference in GH peak was seen after SU plus GHRH and PL plus GHRH, nor was any difference seen in AUC between tests. In controls, no difference was seen in GH peaks, while SU priming significantly (P < 0.03) decreased the AUC 90-120 min of GH after GHRH administration. In acromegalics, SU did not change the slight GHRH-induced increase in PRL levels. Our study documents that 5-HT1 D receptors do not interfere with GHRH-stimulated GH secretion in acromegalic subjects. In normals, SU is able to decrease GH response to GHRH, thus confirming that 5-HT1D receptors are able to modulate GH secretion in normals.

Acromegaly↗
PubMed1996

Lack of effect of desmopressin on ACTH and cortisol responses to ovine corticotropin-releasing hormone in anorexia nervosa.

Both arginine vasopressin (AVP) and corticotropin-releasing hormone (CRH) are involved in the release of ACTH in man. Desmopressin (DDAVP), a synthetic analogue of AVP, has been shown to have a CRH-like action (able to promote ACTH and cortisol release) in animals but not in normal man. Nevertheless, DDAVP is able to release ACTH and cortisol in ACTH-dependent Cushing's disease. We studied eight anorexia nervosa (AN) patients [as AN is a condition in which chronic activation of the hypothalamic-pituitary-adrenal (HPA) axis is commonly reported] in a refeeding phase of the disease, to evaluate whether, after weight gain, ACTH and cortisol response to ovine corticotropin-releasing hormone (oCRH) [1 microgram i.v. DDAVP alone and as pretreatment to oCRH (1 microgram kg-1 BW i.v.)-induced secretion of ACTH and cortisol. We studied six normal women as control subjects. No significant differences in ACTH and cortisol responses to oCRH were found between AN patients and control subjects. DDAVP was not able to stimulate ACTH or cortisol release in AN patients or in control subjects, but in the latter it was able to significantly enhance (P < 0.05) ACTH [area under curve (AUC): 590.0 +/- 104.4 pmol L-1 120 min-1] and cortisol (AUC: 28899.0 +/- 6935.2 nmol L-1 120 min-1) responses to oCRH (ACTH AUC: 325.7 +/- 101.7 pmol L-1 120 min-1, cortisol AUC: 14197.4 +/- 2930.0 nmol L-1 120 min-1). The present data show that DDAVP does not stimulate ACTH and cortisol in AN patients or, as previously reported, in normal subjects. However, DDAVP is able to enhance ACTH and cortisol release after oCRH administration in normal subjects but not in AN patients. This finding could be due to a down-regulation of hypophyseal DDAVP V3 receptors in AN as a direct consequence of the hypercortisolaemic status usually present.

Adolescent↗
PubMed1996

Mixed infection by Staphylococcus and Candida, and Wegener's granulomatosis.

We describe the case of a patient who initially presented with pneumonia from Staphylococcus aureus and Candida parapsilosis, which was resolved with antibiotic treatment, but reappeared 6 months later as full-blown Wegener's granulomatosis. The possible pathogenetic correlations between infective agents, in particular Staphylococcus aureus and Candida, and Wegener's granulomatosis are discussed.

Adult↗
PubMed1996

[Sudden and unusual onset of penile plastic induration in 2 patients neurosurgically treated for pituitary macroadenoma].

Induratio penis plastica (IPP) or Peyronie disease is characterized by the developing of fibrotic plaques in the tunica albuginea of penis, that in the latter stages can lead to impotence. The etiology of this disease is still unknown even if various factors such as inflammation, autoimmunity or traumas are involved. Usually it occurs after 40 years of age, even if cases in young patients have been described. The onset of IPP can be acute in about 50% of the patients, while in the others it is characterized by a chronic but progressive progress. In this work, we describe the cases of two patients 52 and 66 years old, who arrived to our department for a decrease of libido and sexual potency in the last months. The patients were not smokers and took no drugs and they had never complain symptoms and signs of IPP. In both subjects an endocrine pattern compatible with partial hypopituitarism was present and in the first patient it was associated with an ACTH-dependent hypercortisolism. Pituitary imaging with MRI showed in both patients the presence of a mass compatible with macroadenoma, that in the first patient showed characteristic of invasiveness. Both subjects underwent transphenoidal neurosurgery with the exeresis of the neoplasia, with resolution of the secondary hypogonadism and reappearance of the sexual potency. With the resume of sexual activity the patients complained the appearance of painful penis bending during erection. Dynamic echographic evaluation of the penis with 7.5 Mhz linear probe, after the intracavernous injection of prostaglandin E1 10 micrograms, showed in both patients the presence of a hyperechogenic plaque in the tunica albuginea compatible with IPP. Both patients underwent successfully surgery for the excision of the plaque and the apposition of a patch of dura mater. The authors want to underlie as the onset of IPP can be sudden, promoted by the resolution of the hypogonadism secondary to pituitary neoplasia, and contemporary to the normalization of testosterone levels.

Adenoma↗
PubMed1995

P0.1 is a useful parameter in setting the level of pressure support ventilation.

OBJECTIVE: The purpose of this study was to investigate whether changes in breathing pattern, neuromuscular drive (P0.1), and the work involved in breathing might help to set the individual appropriate level of pressure support ventilation (PSV) in patients with acute respiratory failure (ARF) requiring ventilatory assistance. DESIGN: A prospective, interventional study. SETTING: An 8-bed multidisciplinary intensive care unit (ICU). PATIENTS: Ten patients with ARF due to adult respiratory distress syndrome (ARDS), sepsis or airway infection were included in the study. Chronic obstructive pulmonary disease (COPD) patients with acute exacerbation were excluded. None of these patients was in the weaning process. INTERVENTIONS: We found a level of pressure support able to generate a condition of near-relaxation in each patient, as evidenced by work of breathing (WOB) values close to 0 J/1. This level was called PS 100 and baseline physiological measurements, namely, breathing pattern, P0.1 and WOB were obtained. Pressure support was then reduced to 85%, 70%, and 50% of the initial value and the same set of measurements was obtained. MEASUREMENTS AND RESULTS: Flow (V) was measured by a flow sensor (Varflex) positioned between the Y-piece of the breathing circuit and the endotracheal tube. Tidal volume was obtained by numerical integration of the flow signal. Airway pressure (P(aw)) was sampled through a catheter attached to the flow sensor. Esophageal pressure (Pes) was measured with a nasogastric tube incorporating an esophageal balloon. The esophageal balloon and flow and pressure sensors were connected to a portable monitor (CP 100 Bicore) that provided real-time display of flow, volume, P(aw) and Pes tracings and loops of Pes/V, P(aw)/V and V/V relationships. The breathing pattern was analyzed from the flow signal. Patient work of breathing (WOB) was calculated by integration of the area of the Pes/V loop. Respiratory drive (P0.1) was measured at the esophageal pressure change during the first 100 ms of a breath, by the quasi-occlusion technique. When pressure support was reduced, we found that the respiration rate significantly increased from PS 100 to PS 85, but varied negligibly with lower pressure support levels. Tidal volume behaved in a similar way, decreasing significantly from PS 100 to PS 85, but hardly changing at PS 70 and PS 50. In contrast, WOB and P0.1 increased progressively with decreasing pressure support levels. The changes in WOB were significant at each stage in the trial, whereas P0.1 increased significantly from PS 100 at other stages. Linear regression analysis revealed a highly positive, significant correlation between WOB and P0.1 at decreasing PSV levels (r = 0.87), whereas the correlation between WOB and ventilatory frequency was less significant (r = 0.53). No other correlation was found. CONCLUSIONS: During pressure support ventilation, P0.1 may be a more sensitive parameter than the assessment of breathing pattern in setting the optimal level of pressure support in individual patients. Although P0.1 was measured with an esophageal balloon in the present study, non-invasive techniques can also be used.

Adolescent↗