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Biomedical subjects

E Rossi

Publications and source records attributed to E Rossi.

At least 199 records · Page 11Linked to original sources
PubMed1994

Replicon clusters may form structurally stable complexes of chromatin and chromosomes.

Nuclear DNA replication was monitored 'in situ' in pea nuclei with the bromodeoxyuridine antibody technique. The labelling appeared to be restricted to a number of finely distinct spots. The labelling was followed through three subsequent cell cycles in meristematic and differentiating pea root cells. The results show that the spots as seen just after the labelling persist distinctly over the mitotic chromosomes as well as in the nuclei of the following cell cycles up to 44 hours after the pulse. Moreover, they are also present in the nuclei of differentiating cells. The spots over the mitotic chromosomes in specific cases give rise to a dynamic banding. Nuclei of the second and third cycle show absence of labelling in specific zones, owing to the segregation of the labelled strands of chromosomal DNA. The maintenance of the spotted appearance of the replication clusters through all stages of the three subsequent cell cycles may be an indication in favour of the hypothesis that such clusters represent structurally stable replicon complexes held together by the nuclear matrix and the chromosome scaffold.

Bromodeoxyuridine↗
PubMed1994

Antiphospholipid antibodies and risk of intrauterine late fetal death.

STUDY OBJECTIVE: Goal of the study was to analyze the relationship between anticardiolipin antibodies, lupus anticoagulant and the risk of intrauterine late fetal death. DESIGN: A case-control study was conducted in a network of general and teaching hospitals in northern Italy. Cases studied were 99 women (median age 27 years), without clinical evidence of systemic lupus erythematosus or other immunological disorders who had an 'unexplained' intrauterine fetal death at or after the 20 weeks of gestation. The control subjects were 85 women (median age 28 years) who gave birth at term (> 37 weeks gestation) to healthy infants on randomly selected days at the same hospitals where cases had been identified. RESULTS: The presence of lupus anticoagulant was detected in four of the 99 cases (4%, 95% confidence interval 2%-15%) and none of the 85 controls. A total of 10 out of the 89 cases (11%, 95 confidence interval 6%-23%), but none of the 79 controls for whom anticardiolipin antibodies value was available had elevated anticardiolipin antibodies; this difference was statistically significant (chi 2(1) = 9.38, p < 0.01).

Adolescent↗
PubMed1994

Activation of the galectin-1 (L-14-I) gene from nonexpressing differentiated cells by fusion with undifferentiated and tumorigenic cells.

Expression of the galectin-1 (L-14-I) gene, elevated in most differentiated and transformed cell lines, has been studied in cell hybrid systems. Fusion of L-14-I nonproducing rat liver differentiated FAO cells with dedifferentiated rat liver BRL3A cells leads to extinction of liver-specific gene expression while L-14-I mRNA levels remain high. Interspecific hybrids produced by fusion of tumorigenic human osteosarcoma 143TK- with FAO cells show loss of both differentiated functions and tumorigenic phenotype and activation of the FAO L-14-I alleles. Increased expression of rat L-14-I alleles was also observed in human osteosarcoma x rat thyroid cells transient heterokaryons. The data presented here show that expression of the L-14-I gene is subject to dominant positive control and that it correlates with loss of differentiation-specific functions, but it is independent from tumorigenicity. L-14-I activation in FAO cells is achieved by treatment with 5-azacytidine. This result suggests that DNA demethylation is responsible or a prerequisite for L-14-I activation in hybrids.

Alleles↗
PubMed1993

[Hemolytic-uremic syndrome in children: a 19-year retrospective study].

Forty-two children (22 girls and 20 boys, ranging in age between 2 months and 13 years, median age 17 months) were admitted with acute hemolytic-uremic syndrome to the University Children's Hospital, Berne from 1973 to 1991. Seventeen patients developed hypertension and 30 renal failure. Three out of the 19 cases necessitating acute dialysis progressed to end stage renal failure. Four out of the 7 patients with signs of severe central nervous system involvement died. The initial clinical course was consistently more favourable in 35 patients with diarrheal prodrome. Increased protein excretion in association with high blood pressure was observed in 4 patients with initial favourable course who were examined one year after disease onset. This study indicates the generally favourable immediate prognosis of childhood hemolytic uremic syndrome and the possible persistence of high blood pressure and pathological proteinuria on follow-up.

Child↗
PubMed1993

D8S7 is consistently deleted in inverted duplications of the short arm of chromosome 8 (inv dup 8p).

Ten patients with inverted duplication of 8p (inv dup 8p) were studied with cytogenetic, biochemical and molecular techniques. The duplication for the region 8p12-p22 was always associated with a deletion of the locus D8S7 (mapped in 8p23.1) as demonstrated with the probe pSW50 by both in situ hybridization and Southern blot. Restriction fragment length polymorphisms detected by probes pSW50 (1 case) and by pG2LPL35 (locus LPL) (two cases) were informative as to a maternal origin of the anomaly. The activity of glutathione reductase, whose gene maps in the duplicated region at 8p21.1, was increased in all patients. The recognizable phenotype of inv dup 8p includes neonatal hypotonia, prominent forehead, large mouth with everted lower lip, abnormally shaped large ears, brain malformations and severe mental retardation. Our findings indicate that the chromosome rearrangement is homogeneous at least for the presence of the deletion and support the hypothesis of a common mechanism of origin.

Abnormalities, Multiple↗
PubMed1993

Types, stability, and phenotypic consequences of chromosome rearrangements leading to interstitial telomeric sequences.

Using in situ hybridisation, we identified interstitial telomeric sequences in seven chromosomal translocations present in normal and in syndromic subjects. Telomeric sequences were also found at the centromeric ends of a 4p and a 4q caused by centric fission of one chromosome 4. We found that rearrangements leading to interstitial telomeric sequences were of three types: (1) termino-terminal rearrangements with fusion of the telomeres of two chromosomes, of which we report one case; (2) rearrangements in which an acentric fragment of one chromosome fuses to the telomere of another chromosome. We describe four cases of Prader-Willi syndrome with the 15q1-qter transposed to the telomeric repeats of different recipient chromosomes; (3) telomere-centromere rearrangements in which telomeric sequences of one chromosome fuse with the centromere of another chromosome. We describe two examples of these rearrangements in which not only telomeric sequences but also remnants of alphoid sequences were found at the fusion point. Instability at the fusion point of the derivative chromosome was found in the Prader-Willi translocations but we were unable to correlate this instability with culture conditions. The two subjects with the termino-terminal rearrangement and the centric fission respectively have normal phenotypes. The two patients with telomere-centromere fusions were unbalanced for the short arm of an acrocentric chromosome and had failure to thrive; one of them also had dysmorphic facies. We postulate that these phenotypes could be the result of uniparental disomy.

Chromosome Aberrations↗
PubMed1993

Trisomy 10qter confirmed by in situ hybridisation.

We report a boy with multiple congenital anomalies compatible with trisomy for the distal region of the long arm of chromosome 10 and a male karyotype with one 18p+. In situ hybridisation with a cDNA for ornithine aminotransferase (OAT), whose locus maps to 10q26, confirmed the clinical suspicion of distal trisomy 10q. Subterminal localisation of the labelling signals on chromosome 10 and on the der(18) indicated the localisation of the OAT locus in the proximal part of 10q26. Two clusters of labelling signals were also found on the pericentromeric and proximal portion of the X chromosome short arm, thus confirming the presence in this region of two non-adjacent OAT pseudogenes. The phenotypic similarities of this patient to previously reported cases provide further support for the delineation of trisomy 10qter as a specific, clinically recognisable syndrome.

Abnormalities, Multiple↗
PubMed1993

Effects of a chronic treatment with octreotide in patients with functionless pituitary adenomas.

The effects of a chronic treatment with octreotide were evaluated in 19 patients affected with functionless pituitary adenomas. Octreotide caused a significant decrease of GH and IGF-I levels in all the patients and no significant change in thyroid, adrenal and gonadal function. In contrast, during the therapy, the glucose response to an oral glucose tolerance test considerably increased and was delayed, while the insulin response decreased and was delayed. Serum alpha-subunit (alpha-SU) was above normal in 10 of 16 patients in which this evaluation was performed: octreotide caused a significant decrease (p < 0.01) of alpha-SU levels in 6 of these 10 patients. Octreotide did not induce any significant change in visual fields except in 1 patient, who had a great improvement of visual perimetry and a decrease of alpha-SU levels but unmodified CT scan features. In our series of patients, octreotide was ineffective in reducing tumor mass. The efficacy of octreotide might rely on the presence of somatostatin receptors on adenoma-cell membranes. Therefore patients with functionless adenomas to be treated with octreotide might be identified with pituitary scintiscan using the recently available labeled 111In-octreotide.

Adenoma↗
PubMed1993

Tumor necrosis factor in plasma and peritoneal fluid of women with and without endometriosis.

To determine whether in vivo levels of tumor necrosis factor a in plasma and peritoneal fluid differ in infertile subjects with and without endometriosis, peripheral blood and peritoneal fluid samples were collected in 94 women undergoing laparoscopy for infertility. Quantitative determinations of tumor necrosis factor a were performed by an enzyme immunoassay test. Tumor necrosis factor a levels were below the detection limit (10 pg/ml) in plasma and peritoneal fluid of 42 (91%) and 30 (90%) patients with endometriosis and 40 (83%) and 31 (91%) subjects without the disease, respectively. In our series, plasma and tumor necrosis factor a levels were not different in infertile women with and without endometriosis.

Adult↗
PubMed1993

Fish oil derivatives as a prophylaxis of recurrent miscarriage associated with antiphospholipid antibodies (APL): a pilot study.

Since 1989, 22 patients with persistent antiphospholipid syndrome (PAPS) associated with recurrent miscarriage (defined as three or more miscarriages) were treated with fish oil, equivalent to 5.1 g eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) at a ratio of 1.5 EPA to DHA. Twenty-two patients had 23 pregnancies (one patient had two pregnancies) over a period of 3 years. There was only one intrauterine fetal death at the 27th week associated with pre-eclampsia. Twenty-one pregnancies, 19 of which ended after the 37th week, produced a baby. Two pregnancies ended with cesarean section for pre-eclampsia at 30th and 35th week of gestation and one is ongoing at 32nd week. All babies are well. The weight at birth of babies delivered at term was always > 2500 g. These encouraging results favour a therapeutic role, without any adverse reaction, of fish oil to prevent recurrent miscarriage in PAPS.

Abortion, Habitual↗
PubMed1993

Overexpression of c-kit in a leukemic cell population carrying a trisomy 4 and its relationship with the proliferative capacity.

The expression of c-kit and its ligand, the stem cell factor (SCF), was studied in five cases of acute myeloid leukemia. One of these had a trisomy of chromosome 4, where the c-kit oncogene is located. In this case, the c-kit oncogene was overexpressed, but matched by a low expression of its ligand, SCF. The molecular evaluation of the growth rate by c-myc and the histone H3 expression indicated that the growth fraction of this cell population was very low. In one of the other leukemic cell populations studied, characterized by a low expression of c-kit and an elevated expression of the SCF, the growth fraction was also very low. Our results suggest that at least for some receptor oncogenes, the simple overexpression cannot be taken as an indication that the oncogene is involved in the deregulation of cell proliferation.

Base Sequence↗
PubMed1993

[Neurological events in infective endocarditis].

PURPOSE: The study of frequency, modalities and course of neurological complications of infective endocarditis (IE), as well as the current indication and value of supplementary examinations. METHODS: Sixty-three patients with IE, 39 with native valve and 24 with valvar prosthesis, were prospectively studied; the mean age was 42 years and 45 (71.4%) were males. Two groups were formed: A) 41 patients without neurological events and B) 22 patients who presented 28 neurological events before or during hospitalization: ischemic cerebrovascular accident 20, hemorrhagic cerebrovascular accident 2, meningeal hemorrhage 2, meningitis 2, brain abscess 1 and seizure 1. All patients were submitted to neurological clinical examination; 57 computerized tomographies of the cranium, 28 arteriographies and 32 cerebrospinal fluid analysis were performed. RESULTS: The incidence of neurological events corresponded to 34.92% of IE patients, with a clear predominance (85.71%) of vascular as compared to infectious manifestations. Mortality was 2.32 times higher in group B patients (22.73% x 9.76%), albeit p = 0.256, and was not related to staphylococcal etiology. The neurological events were not related to sex, age and presence of valvar prosthesis. The presence of neurological complications was greater (p = 0.047) in patients with simultaneous infections in two valves (mitral and aortic) and also (p = 0.00884) in those with IE in prosthesis implanted for less than three months. All supplementary neurological examinations in group A were normal. CONCLUSION: 1) Occurrence of neurological events is a factor which influences the prognosis of IE; 2) supplementary neurological examinations did not reveal subclinical neurological complications; 3) neurological complications were significantly more frequent in patients with simultaneous mitral and aortic valve IE; 4) IE in prosthesis implanted for less than 3 months has a greater probability to develop a neurological picture as compared to IE in prosthesis implanted for more than 3 months.

Adolescent↗