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Biomedical subjects

A Angeli

Publications and source records attributed to A Angeli.

At least 217 records · Page 12Linked to original sources

Plasma steroid responses to circadian-stage-specified injection of different doses of the ACTH analogue alsactide (ACTH 1-17) in healthy adult human males.

Plasma cortisol, progesterone, testosterone and aldosterone levels were measured on serial blood samples drawn in 10 healthy adult human males up to 6h after single administration at about 07 of increasing amounts of the short-chain analogue ACTH-agonist alsactide (Synchrodyn 1-17). The following doses were employed: 2, 4, 8, 10 and 20 micrograms subcutaneously (s.c.), as well as 2, 4 and 8 micrograms intravenously (i.v.). Data were compared with those obtained by placebo (isotonic saline) injections. The s.c. injections of 2 and 4 micrograms resulted to be ineffective in changing the hormonal pattern. A significant rise of cortisol and progesterone, but not of aldosterone and testosterone, followed the s.c. injections of 8 and 10 micrograms. The differential pattern of the glucocorticoid vs. the mineralocorticoid response was also apparent after the s.c. injection of 20 micrograms alsactide; when compared with placebo, this dose was able to elicit a significant increase of all examined hormones except testosterone. All i.v. injections of 2, 4 and 8 micrograms alsactide were effective; the highest dose did cause a sustained rise of plasma cortisol, progesterone and aldosterone, but also the other doses were able to change significantly the mineralocorticoid levels. These results provide evidence that circadian-stage-specified s.c. or i.v. administration of the analogue can be employed in the clinical practice for enhancing selectively and transiently the morning glucocorticoid secretion.

Adrenocorticotropic Hormone↗

Circadian profile of plasma cortisol and aldosterone in post-traumatic comatose patients under high-dose dexamethasone treatment.

Six comatose patients hospitalized in an intensive care unit immediately following an acute trauma with severe brain injury (road or industrial accident) were examined through out three consecutive 24-h cycles in the first week after trauma, when receiving intramuscularly 12 mg daily of dexamethasone-21-phosphate. Intravenous or enteral nutrition was supplied continuously. Plasma cortisol and aldosterone were measured on blood samples drawn at 4-h intervals. Data were analyzed both by conventional chronograms and by rhythmometric analysis according to the Cosinor procedures. A normally-synchronized circadian pattern of plasma cortisol was recognizable in all cases in the face of the lack of consciousness and of the pharmacological administration of dexamethasone. Acrophase was located at 08:56, with a 95% confidence region vastly overlapping the corresponding region of the controls. By contrast, the circadian pattern of plasma aldosterone appeared to be disrupted; irregular fluctuations were recorded along the entire day. The Cosinor analysis did not detect a significant rhythm of plasma aldosterone during the examined 24-h cycles. Data obtained with the present investigation demonstrate that comatose patients within a few days after severe head injury and given high-dose corticoid treatment do maintain the normal circadian organization of the plasma cortisol, whereas loose that of the plasma aldosterone. Our findings are compatible with the concept that glucocorticoid rhythmicity is particularly resistant to acute injury; the mineralocorticoid rhythmicity appears more labile probably as a consequence of the plurifactorial modulation.

Adolescent↗

Involvement of Ca2+-dependent pathways in the inhibition of human natural killer (NK) cell activity by cortisol.

The role of Ca2+ as a second messenger of the glucocorticoid inhibition of human natural killer (NK) cell activity was evaluated using Ca2+ entry blockers (verapamil and its desmethoxy derivatives LU46973 and LU47093), calmodulin antagonists (pimozide and two naphthalensulfonamide derivatives, W-7 and W-13), the Ca2+ channel agonist BAY K 8644 and the calcium ionophore A23187. Peripheral blood mononuclear (PBM) cell preparations were incubated for 20 h with 1 x 10(-6) M cortisol and these agents in various combinations (concentration range: 1 x 10(-9) -1 x 10(-5) M) and then assayed in a direct 4-h cytolytic assay using 51Cr-labeled K 562 target cells. Exposure to cortisol led to a significant reduction of NK cell activity (about 50% vs. spontaneous activity). Ca2+ entry blockers and calmodulin antagonists were per se minimally effective, but significantly enhanced cortisol-dependent inhibition of NK cell activity. Raising extracellular Ca2+ by CaCl2 or intracellular Ca2+ by the calcium channel agonist BAY K 8644 or the ionophore A23187 resulted in an appreciable reduction of these effects. Similar results were obtained when these substances were added to monocyte-depleted or NK cell-enriched suspensions exposed to cortisol. Our data are consistent with the view that extra- and intracellular Ca2+ plays a role in the control of human NK cell activity. It is also conceivable that both calcium flux into the cell and the calcium calmodulin system are involved in the cortisol-induced inhibition of natural cytotoxicity.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗

Interleukin 2 up-regulates glucocorticoid receptor number in human peripheral blood mononuclear cells and the osteosarcoma cell line Saos-2 in vitro.

Glucocorticoids are well-recognized modulators of immunocytes and osteoblasts via specific receptor-mediated mechanisms. We have evaluated the in vitro effect of interleukin 2 (IL-2) on the expression of glucocorticoid receptors (GRs) in peripheral blood mononuclear cells (PBMCs) obtained from healthy donors and osteoblast-like Saos-2 cells. Aliquots of PBMC or Saos-2 cells were incubated for 20 h in the presence or absence of recombinant human IL-2 (100 IU/mL) at 37 degrees C. After incubation, a [3H]dexamethasone radioligand-binding assay and Scatchard analysis were used to determine GR-binding parameters in both cell populations. Saos-2 cells basally express higher numbers of GR than PBMCs. After IL-2, a significant increase in GR number was found for both PBMCs and Saos-2 cells. The relative increase was higher in Saos-2 cells; in PBMCs, the apparent affinity fell to almost half. These data represent an additional piece of evidence that cytokine and steroid hormones may act in a complementary way to regulate specific cell functions.

Adult↗

Serum levels of carboxyterminal propeptide of type I procollagen in cancer patients with osteoblastic and osteolytic bone metastases.

Serial monitoring of serum and urinary markers of bone regeneration may provide an indirect assessment of the activity of bone metastases. We measured serum levels of carboxyterminal propeptide of type I procollagen (PICP), a new marker of bone formation, in 236 control subjects, stratified according to age and sex, and in 122 cancer patients: 80 with breast cancer (BC) (42 with osteolytic bone metastases) and 42 with prostate cancer (PC) (31 with osteoblastic bone metastases). An inverse correlation between age and serum PICP levels was found in healthy men (r = -0.30), but not in women, PICP levels were significantly higher in patients with osteoblastic metastases compared to age-matched control subjects and patients with advanced disease not involving the skeleton. The sensitivity of PICP was 64% for detecting osteoblastic metastases, and 12% for detecting osteolytic metastases. Serum PICP determination may have a diagnostic role for osteoblastic activity.

Adult↗

Evaluation by dual energy X-ray absorptiometry of changed bone density in metastatic bone sites as a consequence of systemic treatment.

Fourteen cancer patients with bone metastases from various primary malignancies were submitted to repeated dual X-ray absorptiometry (DEXA) scan before and after systemic antineoplastic treatments. In the nine patients with lytic lesions the Bone Mineral Density (BMD) increased after chemotherapy + pamidronate in four (by +11.2%, +7.5%, +5.0% and +6.6%, respectively), decreased in four (by -19.9%, -8.1%, -7.5%, and -7.0%, respectively) and remained unchanged in one. BMD changes paralleled variations in painful symptomatology and biochemical markers. In patients with blastic metastases the BMD on target metastatic lesions did not change after hormone therapy or chemotherapy in one case but showed a significant increase in four. BMD increase was associated to bone pain improvement and PSA decrease in two cases, and with a worsening in skeletal pain and/or serum PSA in the remaining two. Our data suggest that BMD evaluation by DEXA instrument may be a reliable tool in assessing the response of bone metastases to treatment.

Absorptiometry, Photon↗

[Incidence and socioeconomic burden of hip fractures in Italy].

OBJECTIVES: The aim of this study was to evaluate the trend of the incidence and costs of hip fractures in Italy. METHODS: The incidence of hip fractures after 45 years of age in both females and males during the years 1999-2002 was obtained by analyzing the Italian Ministry of Health national hospitalization database, according to the diagnosis codes of International Classification of Diseases, Clinical Modification, 9th edition (IDC-9-CM) that indicate femoral fracture. We have computed all direct costs sustained by the National Health Service for hospitalization and treatment of hip fractures on the basis of the value of the Diagnosis Related Groups (DRG) referring to hip fractures. The expenses of rehabilitation and indirect expenses were based on estimates. RESULTS: In 2002, more than 86,000 hip fractures were registered in Italy in male and female patients over 45 years old, with 9% progression compared to 1999; 77% were female and 80% were over 75 years of age. In 2002 the direct costs of hospitalization, in the patients over 65 years alone, were almost 400 million euros, with an increase of 15% as compared to 1999. Considering also estimated rehabilitation costs, social aid and indirect costs, we estimate that hip fractures due to age-related osteoporosis created over a billion euros in expenses in 2002. CONCLUSIONS: Preventive intervention regarding the risk of hip fracture in elderly patients is urgent.

Aged↗

Metabolic effects of single-dose pamidronate administration in prostate cancer patients with bone metastases.

BACKGROUND: Increased osteolysis usually accompanies sclerotic bone metastases from prostate cancer. This provides a rationale for the use of bisphosphonates to treat bone pain and prevent skeletal complications. METHODS: The fasting urinary levels of calcium, hydroxyproline (OHPRO), pyridinolines (PYD), deoxypyridinolines (DPYD), collagen cross-linked N-telopeptide (NTX) and the serum values of calcium, total alkaline phosphatase and relevant bone isoenzyme, bone gla protein (BGP), carboxy-telopeptide of type I collagen (ICTP) and parathyroid hormone (PTH) were determined at baseline and on the 15th, 30th, 60th and 90th days after single-dose (90 mg) pamidronate administration in 35 consecutive prostate cancer patients with bone metastases. These biochemical indices and serum interleukin 6 (IL-6) were also measured after four days in the last consecutive 17 cases. RESULTS: PYD, DPYD and NTX showed a significant decrease lasting four weeks (p<0.01, <0.01 and <0.001, respectively). OHPRO and ICTP did not change significantly. The NTX decline was greater than that of PYD and DPYD (maximum percent decrease: -71.3, -23.1 and -28.2, respectively). Bone formation markers and serum calcium did not change significantly. Serum PTH showed a rapid initial increase followed by a slow decrease (p<0.001). DPYD and NTX patterns did not correlate with changes in bone pain. As observed in the last 17 cases, the maximum osteolysis inhibition after pamidronate occurred on the fourth day after drug infusion. Serum IL-6 levels showed a short-lived decrease preceded by a transient rise on the fourth day. CONCLUSIONS: Pamidronate is able to induce a decrease in bone resorption without significantly influencing bone formation. The maximum decrease in bone resorption occurs very early. NTX is the most sensitive bone resorption marker in bisphosphonate therapy monitoring. Changes in IL-6 but not bone resorption markers may be useful in the prediction of symptomatic response.

Adult↗

[Glucocorticoid-induced osteoporosis: recent findings].

The clinical features, pathogenesis and management of bone involvement in Cushing's syndrome are briefly reviewed. Personal data on bone mineral density and markers of bone turnover in Cushing's syndrome and adrenal incidentalomas are also reported. As long ago as 1932, Harvey Cushing recognized osteoporosis as a serious consequence of endogenous hypercortisolism. The introduction of cortisone in the therapy of autoimmune, rheumatic, allergic or dermatologic disorders was followed by several reports of detrimental effects on bone of patients who had undergone prolonged glucocorticoid treatment. Due to the rarity of Cushing's syndrome, most of the studies in the literature on glucocorticoid-induced osteoporosis refer to exogenous over-exposure to cortisone and its synthetic derivatives. Only a small number of works concern endogenous hypercortisolism, even if the characteristics of bone damage seem qualitatively the same. Finally, very few data are reported on the hypothetical detrimental effect on bone in the condition of the silent hypercortisolism of adrenal incidentalomas. Glucocorticoid-induced osteoporosis in Cushing's syndrome often results in vertebral fractures, and bone loss is more evident in trabecular than in cortical bone. Notwithstanding some distinctive features in osteoporosis induced by endogenous and exogenous glucocorticoid excess, the common eventual picture is notable bone damage that involves mainly the trabecular bone. Prompt and effective therapy is mandatory to reduce the risk of fractures. The present options include calcium and vitamin D supplementation, estrogen replacement therapy, bisphosphonates, either oral or parenteral. A novel approach to the clinical problem of glucocorticoid-induced osteoporosis might, in the future, be based on studies on selective glucocorticoid receptor modulators, a new class of synthetic glucocorticoids that exhibit significant anti-inflammatory and immunosuppressive activities, with reduced side effects on bone.

Adrenal Cortex Neoplasms↗

[Family structure and income: a first analysis on cross-section data].

"In the paper the hypothesis of differences in household incomes depending on the sex of the householder is investigated. The data come from the 1991 Bank of Italy Survey on Household Income....A multiple regression model has been formulated in order to appreciate the contribution of the householder's sex to the family and per-capita income differentials." (SUMMARY IN ENG)

Demography↗

Effects of physiological concentrations of steroid hormones and interleukin-11 on basal and stimulated production of interleukin-8 by human osteoblast-like cells with different functional profiles.

OBJECTIVE: IL-8 is a CXC chemokine involved in the pathogenesis of articular damage in rheumatoid arthritis. Local hyperproduction of IL-8 has been suggested to play a role in subchondral bone loss, since it suppresses osteoblast activity and promotes osteoclasts recruitment. Osteoblasts are a source of IL-8; its secretion is regulated by a number of hormones and cytokines. The aim of the present study was to evaluate the single and combined effects of physiological concentrations of cortisol, 17 beta-estradiol and IL-11 upon basal and IL-1 beta-inducible production of IL-8 in two human osteoblast-like cell lines, Saos-2 and MG-63. METHODS: Cells were incubated with cortisol (0.01 to 1 microM), 17 beta-estradiol (10 to 1000 pg/ml), IL-11 (1 to 100 ng/ml), in presence or absence of IL-1 beta (10 ng/ml), for 20 h. Combinations of 17 beta-estradiol and cortisol, and of IL-11 and cortisol, were also tested. After incubation, IL-8 levels in supernatants were measured by ELISA. RESULTS: Cortisol dose-dependently inhibited spontaneous IL-8 secretion in both cell lines, although statistical significance was attained in the MG-63 cells only (P < 0.01); no effect of 17 beta-estradiol was apparent. With regard to IL-1 beta-inducible production, cortisol dose-dependently inhibited IL-8 release in both cell lines (P < 0.01); 17 beta-estradiol resulted in only a non-significant decrease in Saos-2, but not in MG-63 cells. 17 beta-estradiol did not alter the effects of cortisol in experiments involving co-incubation. IL-11 did not have any effect on spontaneous IL-8 release, but exerted a significant inhibitory effect on IL-1 beta-inducible release in MG-63 cells (P < 0.05); no additional effect was observed upon the degree of cortisol-dependent inhibition. CONCLUSION: Cortisol is a potent physiological inhibitor of IL-8 production by osteoblast-like cells. The results of the present study support the use of exogenous supplemental glucocorticoids to prevent the deleterious effects of excess IL-8. The estrogenic milieu and local concentrations of IL-11 have little if any effect on the IL-8-dependent mechanisms of disease.

Cell Line, Tumor↗