PubMed Health⌕ Search

Biomedical subjects

G Bossi

Publications and source records attributed to G Bossi.

At least 55 records · Page 3Linked to original sources

Final height in Turner syndrome patients treated with growth hormone.

Growth hormone (GH), alone or in combination with anabolic steroids, seems to improve the growth rate in Turner syndrome, but to exert a less striking effect on the final height (FH). Reports on the FH usually lack a control group, and the GH effect is determined using the gain in centimeters over projected height. Out of a cohort of 32 Turner syndrome girls under recombinant human GH (rhGH) therapy (0.5 IU/kg/week during the 1st year and 1 IU/kg/week subsequently), 18 (treated for 3-6 years) attained FH. The mean chronological age at the first examination was 9.6 +/- (SD) 2.1 years and at the start of GH therapy 13.0 +/- 2.0 (range 8.8-17.2) years. Eighteen untreated subjects matched for chronological age and karyotype served as control group. The FH as SDS according to Lyon and to unpublished Italian Turner syndrome girl standards was not significantly different as compared with pretreatment. In comparison with Italian cross-sectional Turner syndrome standards (FH 142.5 +/- 7.0 cm), the FH of the control group was quite similar (142.2 +/- 4.9 cm), whereas the rhGH-treated group showed a FH of 147.6 +/- 7.3 cm with a mean increment of about 5 cm. The height gain during therapy (as delta height in SDS either according to Lyon or to Italian SDS standards) was compared for each girl with that of a matched girl of the control group during a comparable observation period. A significantly different delta height was observed in the treated versus control groups: 0.3 +/- 1.1 vs. -1.0 +/- 0.8 according to Lyon (p < 0.001) and 0.8 +/- 0.7 vs -0.3 +/- 0.5 according to Italian standards (p < 0.001). If we compared the FH with the projected height according to Lyon standards, the height gain (as delta height in cm) was significantly higher than in the untreated subjects (-1.1 +/- 4.8 vs. -6.2 +/- 3.9 cm; p < 0.05). It seems worthwhile to undertake GH treatment in Turner syndrome girls who represent a very short stature population, even though the response is less significant than in classic GH deficiency and shows a striking variability, probably due to a sort of peripheral resistance.

Body Height↗

Conserved regions in the cytoplasmic domains of the leukocyte integrin alpha L beta 2 are involved in endoplasmic reticulum retention, dimerization, and cytoskeletal association.

Selected functions of integrins, including regulated cytoskeletal association and transmembrane signaling, depend on a poorly defined bidirectional communication between the extracellular and cytoplasmic domains of the alpha and beta subunits. To investigate this problem in the leukocyte integrin alpha L beta 2 (LFA-1), we generated a series of cytoplasmic truncation or internal substitution mutants of the alpha L and beta 2 cytoplasmic domains, and assessed their biochemical and functional properties upon ectopic expression in constitutively adherent cells. Expression of the alpha L beta 2 heterodimer in stably adherent cells is sufficient to promote its constitutive cytoskeletal association. Structural determinants for such association are located in selected regions of the beta 2 cytoplasmic domain, which display functional interdependence. In addition, a conserved region (Arg733-Lys742) in the beta 2 cytoplasmic domain seems to be critical not only for its cytoskeletal association, but also for endoplasmic reticulum retention, assembly, and transport to the plasma membrane of the mature alpha L beta 2 heterodimer. Analysis of deletion mutants of the alpha L subunit demonstrates a role of the conserved, membrane-proximal GFFKR motif in conferring stability to the alpha beta complex, possibly because of its direct involvement in heterodimer formation. We propose that a previously uncharacterized association of defined subregions of the cytoplasmic domains of integrin alpha and beta subunits affects the dimerization and regulated function of the adhesion receptor.

Allosteric Regulation↗

Unusual secondary tumors after childhood lymphoid malignancy.

Second malignant neoplasms (SMN) in individuals who survived childhood cancer have been reported with increasing frequency during the last decades. The overall probability of developing second malignancy for children treated for cancer was estimated at about 2-5% at 25 years. In children, the tumors most often associated with the development of SMN are retinoblastoma and Hodgkin's disease. We report two cases of unusual second tumors in two patients cured of lymphoid malignancy: one boy cured of acute lymphoblastic leukemia developed mediastinal ganglioneuroma nine years later and one girl had gastric carcinoma seven years after Hodgkin's disease. Both developed a tumor in nonirradiated areas. Gastric carcinoma and ganglioneuroma are not reported as recurrent SMN in survivors after childhood cancer, with one single case of gastric carcinoma and one of ganglioneuroblastoma having been reported as second tumor in survivors after childhood cancer.

Adolescent↗

Retinoic acid and cAMP differentially regulate human chromogranin A promoter activity during differentiation of neuroblastoma cells.

We report the first evidence that differential transcriptional regulation of human chromogranin A (CHGA) gene expression occurs during in vitro treatment of tumorigenic neuroblastoma (NB) cells with retinoic acid (5 microM) and/or dibutyryl-cAMP (1 mM). The CHGA gene encodes a tissue specific protein restricted to cells of the diffuse neuroendocrine system, but also widely expressed among NB tumours. We previously reported that CHGA as well as other neuroendocrine markers are modulated during NB differentiation in vitro. To investigate, at the molecular level, the mechanisms leading to NB tumour cell differentiation during the treatment with biologically active compounds, we sequenced and functionally characterised 2169 bp of a genomic DNA clone encompassing the 5' flanking region of the human CHGA gene. Computer-assisted analysis of the sequence revealed the presence of a cAMP responsive element at positions -56 to -49, and Sp1 binding sites at positions -181 to -176 and -216 to -210. Two novel 9 bp motifs, located at position -462 to -454 and -91 to -83 of the CHGA promoter were identified in the regulatory regions of two other neuroendocrine genes encoding for tyrosine hydroxylase and neuropeptide Y. In addition, in the first 1000 bp of the untranslated 5' region, we found the presence of several putative DNA binding sites of bHLH molecules, a protein family regulating tissue specific differentiation. Transient transfection experiments of chloramphenicol acetyltransferase (CAT) deletion constructs, showed the presence of an active promoter within the first 455 bp upstream from the start site. This region conferred tissue specific expression to a CAT reporter gene. In addition, the transcriptional activity of this fragment was modulated during the induction of differentiation of NB cells treated by retinoic acid and/or dibutyryl-cAMP. These observations provide preliminary data regarding CHGA transcriptional regulation in NB cells, and indicate that retinoic acid and cAMP activate distinct, apparently competitive, transcriptional pathways during NB cell differentiation. The molecular characterisation of the mechanisms regulating CHGA expression in tumour and normal neuroendocrine tissue could lead to the identification of novel molecules potentially relevant for future gene therapy of NB tumours.

Base Sequence↗

Membrane fluidization by animycotic bifonazole.

Calorimetry, nuclear magnetic resonance and X-ray diffraction techniques have been used to obtain thermodynamic and structural information on dipalmitoyl phosphatidylcholine (DPPC) liposomes doped by the antimycotic drug bifonazole in the range 0 < R < 1, where R = moles of bifonazole/moles of DPPC. The technique of spin labeling electron spin resonance (ESR) has also been used to study permeability and fluidity properties. The decrease of the cooperativity at the gel to liquid crystalline phase transition, as shown by ESR an DSC measurements, indicates that bifonazole imparts higher fluidity to the lipid matrix. Increase in permeability of ascorbate ions, after incorporation of bifonazole in the membrane, has been detected by ESR experiments using spin label 5-SASL. 13C NMR spectra indicate that the drug molecule is highly immobilized. X-ray diffraction and freeze fracture TEM results show that the equilibrated phase at room temperature is lamellar and unidimensional together with the presence of small particles and pits of uniform size. A marked hysteresis is evident in the formation of this phase.

1,2-Dipalmitoylphosphatidylcholine↗

Choroid plexus carcinoma: report of one case with favourable response to treatment.

Choroid plexus carcinoma (CPC) is a rare tumor with usually severe prognosis, whose optimal treatment has not yet been established. The exact role of complete surgical resection, chemotherapy, and radiotherapy has been debated but not clarified. We report one girl with CPC diagnosed at age 3 months and apparently cured with minimal surgical resection, chemotherapy, and delayed irradiation. At the age of 8 years, she is well, with minor psychomotor retardation and growth hormone deficiency as the only sequelae.

Antineoplastic Combined Chemotherapy Protocols↗

Abnormalities of plasma lipoprotein composition and fluidity in psoriasis.

We have studied the lipoprotein chemical composition and fluidity, using the fluorescence polarization of the probe 1,6-diphenyl-1,3,5-hexatriene (DPH) in two age- and sex-matched groups of subjects (14 healthy normolipidemic children and 15 psoriatic children). The compositional study has shown a significant increase of the percentage content in triacylglycerol and a significant decrease of the apo-protein content in all lipoprotein fractions of psoriatic children compared to the controls. A significant increase of the percentage content in total cholesterol and of the cholesterol/protein ratio has also been observed in low-density lipoproteins (LDL) and in high-density lipoproteins (HDL) of psoriatic children. The compositional changes were associated with alterations of fluidity in LDL and HDL of psoriatic patients. The modifications of lipoprotein composition and fluidity observed in psoriatic patients could be of physiopathological and clinical relevance in relation to the pathogenesis of the disease.

Apolipoproteins↗

[Quinquad's folliculitis decalvans and tufted hair].

We observed a case of folliculitis decalvans involving the beard and the scalp with a tufted hair folliculitis aspect in the occipital region. The presence of two clinical presentations in the same patient has not been reported in the literature. This would suggest that the two entities could be morphological aspects of the same pathological process which might cause either atrophy with loss or the annexes or tufted hair folliculitis depending upon the depts and destructive capacity of the inflammatory process.

Aged↗

Lipoprotein peroxidation in adult psoriatic patients.

Psoriasis, a chronic inflammatory skin disease characterized by an aberration of lipid metabolism, has been associated with an increased risk for atherosclerosis. Since oxidatively modified lipoproteins are involved in the pathogenesis of atherosclerosis, we investigated the lipid composition and in vitro induced peroxidation of very low density lipoproteins (VLDL) and low density lipoproteins (LDL) from psoriatic patients. 11 male adult psoriatics and 16 male age-matched healthy subjects were studied. Lipid peroxidation of VLDL and LDL was performed by incubation with CuSO4 for 24 h at 37 degrees C. The compositional analysis showed a significant increase in triglycerides and phospholipids, both in VLDL (p < 0.05) and in LDL (p < 0.001) from psoriatic patients, compared with controls. Moreover a significant increase in total cholesterol (TC) (p < 0.01) and apoprotein (P) (p < 0.05) was found in LDL from psoriatics. The levels of thiobarbituric acid reactive substances (TBARS), as a measurement of lipid peroxidation, were significantly higher in Ox-VLDL and in Ox-LDL from psoriatics (p < 0.01) than the corresponding values in controls. Moreover, basal values of TBARS were significantly higher in VLDL and LDL from psoriatic patients than those from controls. In conclusion, the lipoprotein compositional changes associated with the modifications of TBARS before and after Cu2+ treatment of lipoproteins may suggest an increased risk for atherosclerosis in adult psoriatic patients.

Arteriosclerosis↗

Langerhans cell histiocytosis and acute leukemia: unusual association in two cases.

Langerhans cell histiocytosis (LCH) is a non-malignant disorder, whether localized or disseminated, and usually has a favourable prognosis. A possible relationship between LCH and neoplastic diseases has not been assessed up to now even if a few cases have been recorded. We report two new cases of acute leukemia in children with LCH. The first child had acute lymphoblastic leukemia after untreated LCH; the second developed acute promyelocytic leukemia after LCH treated with vinblastine and etoposide. To our knowledge, this is the first case of secondary leukemia after exposure to an epipodophyllotoxin derivative in a child with benign disease. Cooperative studies of large numbers of LCH patients are needed to evaluate a possible association between LCH and acute leukemia, and to identify common risk factors or predisposing agents if such be present.

Antineoplastic Combined Chemotherapy Protocols↗

Changes of plasma lipids and erythrocyte membrane fluidity in psoriatic children.

Psoriasis has been associated with an abnormal plasma lipid metabolism, and changes of erythrocyte membrane lipid composition and fluidity have been shown in adult patients. To investigate whether the alterations of plasma lipids appear also in pediatric patients, we have studied plasma lipids and lipoproteins in 15 prepubertal children affected by mild-to-moderate psoriasis with respect to healthy controls. The patients showed higher levels of plasma total cholesterol (4.44 +/- 0.78 versus 4.03 +/- 0.58 mmol/L), a significant increase of cholesterol associated with HDL (1.39 +/- 0.26 versus 1.13 +/- 0.28 mmol/L, p = 0.02), and a significant decrease of the ratio LDL cholesterol to HDL cholesterol (1.73 +/- 0.6 versus 2.46 +/- 0.8, p = 0.02). By using fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene, we have shown a significant increase in fluidity in erythrocyte membrane of psoriatic children that was associated with a slight, but not significant, decrease in the cholesterol to protein ratio (422 +/- 127 versus 503 +/- 117 nmol/mg). No significant changes of phospholipid fatty acid composition have been shown, in disagreement with previous studies in adult patients. Our results support the relation between childhood psoriasis and plasma lipid changes, which are likely related to the slight compositional changes in erythrocytes. However, the observed abnormalities are expressed differently in children than in adults.

Apolipoproteins↗

Partial response after intensive chemotherapy for adrenal cortical carcinoma in a child.

Adrenocortical carcinoma (ACC) in childhood is a rare tumor with high fatality rate. Available reports provide event free survival rates ranging between 10 to 50%. Optimal treatment has not yet been established; surgery plays a major role, and the value of adjuvant chemotherapy needs to be evaluated further, especially in children who develop recurrent disease and those with metastases at diagnosis. Optimal therapy of ACC has not been established. Surgery has been curative after complete tumor resection. Children with inoperable, recurrent and metastatic ACC have been treated with O,P'DDD, with response rates ranging from 10 to 60% in different series [7,11-20]. Radiotherapy [21] and other anti-cancer drugs have been used [4-22] but their efficacy has not been established. Combination chemotherapy containing oncovin, cisPlatinum, epipodophyllotoxin and cyclophosphamide (OPEC) produced regression of metastatic ACC in a 5-year-old male [23]. We report one girl with relapsed disseminated ACC who showed good, even if temporary, control of the disease, with disappearance of lung, liver and spleen metastases, and marked reduction of the adrenal mass, following combined chemotherapy according to the "eight-drugs-in-one-day" protocol.

Adrenal Gland Neoplasms↗

Plasma lipid changes in psoriatic children.

Plasma lipid, lipoprotein and apoprotein concentrations were determined in psoriatic children and in healthy controls. The plasma total cholesterol (TC) was higher than in controls (p = 0.03). The higher cholesterol levels were explained by an almost significant increase in cholesterol associated with high-density lipoproteins and by the tendency towards higher values of cholesterol associated with low-density lipoproteins and very-low-density lipoproteins. No significant changes of plasma triglycerides were observed. Levels of apoproteins (apo) AI and apo B were not significantly different in psoriatic children; however, the levels of apo B were correlated differently with plasma TC in psoriatic children, and the ratio TC/apo B was significantly increased in patients with respect to the controls, suggesting some differences of plasma lipoprotein lipid/apoprotein relationship in psoriasis.

Adolescent↗