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A Calogero

Publications and source records attributed to A Calogero.

At least 37 records · Page 2Linked to original sources
PubMed1994

HHV-6 infection in Italy: characterization of an endemic isolate and seroepidemiologic analysis.

A biologic, immunologic and molecular characterization of an HHV-6 isolate (BA92) rescued by the peripheral blood mononuclear cells of a child affected by Exanthem subitum is reported. The comparison with the known HHV-6 prototype strains showed that BA92 is indistinguishable from the Z29 isolate, and can be included in the variant B group of HHV-6. A seroepidemiologic analysis of the antibody response to BA92 of normal individuals as well as patients affected by diseases potentially associated to HHV-6 infection has shown an overall seroprevalence of 81%, and that no variations in seroprevalence or in antibody geometric mean titer are observed assaying the sera also against G.S., U1102, or Z29 infected cells, respectively. These findings indicate: (1) HHV-6 infection is widely diffuse in Italy; (2) it is not possible to discriminate between the viral variants by the currently available IF assays, and (3) no conclusions can be drawn on the potential association of HHV-6 with any of the diseases examined.

Journal Article↗
PubMed1994

Nucleotide sequence, genomic organization and synthesis of infectious transcripts from a full-length clone of artichoke mottle crinkle virus.

The complete nucleotide sequence of the genome of artichoke mottle crinkle virus (AMCV), a member of the tombusvirus group, has been determined. The genome is 4790 nucleotides (nt) in length. A full-length cDNA of the AMCV genome has been cloned in pUC9 downstream of the T7 RNA polymerase promoter. Transcripts were infective when inoculated onto Nicotiana clevelandii and N. benthamiana plants. The AMCV genome contains five open reading frames (ORFs). The first ORF from the 5' terminus (ORF1) encodes a protein with a predicted M(r) of 33K. ORF2 extends through the amber termination codon of ORF1 to yield a polypeptide of predicted M(r) 92K and which is the putative RNA-dependent RNA polymerase. ORF3 codes for the coat protein (41K). Two nested ORFs in different reading frames (ORFs 4 and 5) code for a 22K and a 19K polypeptide respectively. Sequence homologies suggest that the 22K protein could be involved in cell-to-cell movement of virus. ORFs 3, 4 and 5 are translated from two 3' coterminal subgenomic (sg) RNAs, the 5' termini of which have been mapped. The two sg RNAs are 2155 (sg1) and 934 (sg2) nt in length. ORF3 is expressed from sg1 RNA whereas ORFs 4 and 5 are potentially expressed from sg2 RNA. Time course experiments with Cynara scolymus protoplasts indicate that during AMCV infection both positive and negative strands of genomic and sg RNAs are produced and that sg2 RNA is produced before and at a higher level than sg1 RNA.

Amino Acid Sequence↗
PubMed1991

Overexpression of uvomorulin in a compaction-negative F9 mutant cell line.

The mutant F9 cell line F9att-5.51 synthesizes reduced amounts of uvomorulin (UM) protein and we hypothesized earlier (Adamson, Baribault, and Kemler, Dev. Biol. (1990), 138, 338) that this may account for its inability to compact into tightly aggregated balls of cells. Subsequently, when 5.51 cells are treated with retinoic acid to stimulate their differentiation, they are unable to form embryoid bodies as do wild-type cells which form an outer epithelial layer of visceral endoderm cells. We have now examined the possibility that the UM protein made in the mutant line is defective, but find that it is normal in structure and stability. The gene coding for UM appears to be normal as does the mRNA which is synthesized at a normal rate but is severely reduced in steady-state measurements of mutant cells. A rescue experiment was performed by increasing levels of UM in mutant cells by means of transfection with a UM expression vector. The resulting cells expressed abundant UM mRNA and protein but were still unable to form compacted aggregates and did not differentiate into embryoid bodies. Interestingly, the stability of endogenous UM mRNA was improved in the presence of exogenous UM; therefore, a positive feedback mechanism contributes to low mRNA levels in mutant cells. The accumulated data suggest that UM in 5.51 cells is unable to mount a compaction activity because a distal connecting link in the multicomponent process initiated by UM is missing or or aberrant. The missing component is likely to connect UM to actin and the cytoskeleton of the cell.

Animals↗
PubMed1990

[Cyclosporin (CyA) and H2 antagonists].

An experimental study on rats in order to discovery any possible interaction between Ciclosporin (CyA) and H2-receptor antagonists has been carried out. The results obtained demonstrated that the serum levels of CyA were higher in rats treated with CyA and Cimetidine or Ranitidine, but not Famotidine. It is probable that the increase of ciclosporinaemia is the consequence of an increased hepatotoxicity due to administration of Cya in association with Cimetidine or Ranitidine.

Animals↗
PubMed1989

Chronobiological evidence for an uncoupling of the Na,K-ATPase to aldosterone in normal renin hypertension.

The Na,K-ATPase activity of erythrocyte membranes is markedly increased in normal-renin essential hypertensives. A temporal shift of the chronobiology of the erythrocyte-membrane-bound Na,K-ATPase in these patients is described. The disorder causes a loss of synchronism between the circadian rhythms of aldosterone and Na,K-ATPase. Such uncoupling phenomenon may explain the inversion of the day/night sodium excretion ratio and other disturbances of sodium metabolism found in essential hypertensives.

Adolescent↗
PubMed1989

Evidence of drug interaction between cyclosporin A and H2-receptor antagonists (cimetidine, ranitidine and famotidine) in Sprague-Dawley rats.

H2-receptor antagonists, such as cimetidine (C), ranitidine (R) and famotidine (F) seem to be effective in the prevention and treatment of stress ulcer in transplant recipients receiving cyclosporin A (CyA). The aim of this study was to detect the possible synergistic nephro- and hepato-toxicity of these drugs, assaying the serum creatinine (SC), ALT, AST levels, and the histological features of 45 young male Sprague-Dawley rats, divided into nine groups of five rats each. After 10 days of treatment the results showed: (i) serum CyA levels were increased in the group receiving daily CyA (5 mg/kg) + R(5 mg/kg) (2430 +/- 403 ng/ml; p less than 0.05 vs. controls) and in the group receiving daily CyA (5 mg/kg) +/- C (10 mg/kg) (2440 +/- 265 ng/ml; p less than 0.01 vs. controls); (ii) ALT and AST levels were increased in this latter group (ALT 223 +/- 133 UL, AST 114.67 +/- 39 UL; p less than 0.01 vs. controls); (iii) SC levels were normal; and (iv) steatosis of the liver was observed in these two groups. These findings suggest that C and R, but not F, may inhibit the hepatic cytochromes P-450 which are involved in the oxidative metabolism of the drugs. Furthermore, the high serum CyA levels seem to play a major role in the appearance of biochemical and histological damage to the liver.

Alanine Transaminase↗
PubMed1987

B- and T-cell non-Hodgkin's lymphomas with large multilobated cells: morphological, phenotypic and clinical heterogeneity.

Ten cases of non-Hodgkin's lymphomas, mainly composed of large multilobated cells, have been studied. Our results are consistent with the view that they represent a somewhat heterogeneous group of lymphoid tumours displaying different morphological, clinical and immunophenotypic features. In B-cell type the large multilobated cells were histologically characterized by prominent nucleoli and distinctly basophilic cytoplasm whereas in the T-cell type they had indistinct or small nucleoli and ill-defined weakly eosinophilic cytoplasm. These differential features between B- and T-cell type were confirmed by electron microscopy. From a clinical standpoint B-cell type was characterized by a constant involvement of lymphoid tissues (lymph nodes and/or Waldeyer's ring); T-cell type showed, on the contrary, a more frequent involvement of extra-lymphoid sites (mainly bone and subcutaneous tissues). Our study provides some morphological features that may be helpful for a correct differential diagnosis in this heterogeneous group of non-Hodgkin's lymphomas.

Adolescent↗
PubMed1986

Effect of gonadotrophin-releasing hormone analogue (GnRH-A) administration on serum gonadotrophin and steroid levels in patients with polycystic ovarian disease.

A gonadotrophin-releasing hormone (GnRH) analogue, D-Ser[TBU]LRH-EA10, (GnRH-A), at a dose of 200 micrograms was given daily for 2 months to 6 women with polycystic ovarian disease (PCO). Prior to therapy the patients presented elevated LH, testosterone (T), oestrone (E1) and dihydrotestosterone (DHT) in the circulation. In response to GnRH-A, these subjects exhibited a marked decrease in circulating T, DHT and androstenedione (A) levels as measured 24 h after GnRH-A injection, by 4 weeks and onwards (P less than 0.05). After 2 weeks of daily administration, the serum LH profile, evaluated by sampling at 2, 4, 7 and 24 h after injection of GnRH-A, was not different from baseline, whereas after 4, 6 and 8 weeks the levels were significantly lower (*P less than 0.01). The profile of serum T levels was unmodified at the second week, but significantly decreased thereafter (*P less than 0.01). At the end of treatment, the E1 concentrations, elevated in pre-injection condition, were markedly decreased. These data demonstrate that in PCO subjects, GnRH-A significantly lowered the elevated levels of androgens commonly found in these patients. The close correlation observed between reduced serum LH and androgen concentrations suggests that pituitary desensitization could be responsible for the reduction in androgen levels, and may be evidence for a gonadotrophin dependence of the elevated concentrations of T in these patients.

Adult↗
PubMed1986

Failure of GnRH analogue to inhibit serum concentrations of testosterone and 17 alpha-hydroxyprogesterone in hCG-substituted hypogonadotropic hypogonadism.

Gonadotropin-releasing hormone analogues (GnRH-A) induce inhibition of testicular function and reduction of serum testosterone (T) in man, but the mechanism involved is still debatable. To elucidate it we studied six patients with hypogonadotropic hypogonadism (HH) in chronic substitution with hCG for correction of androgen deficiency symptoms, and evaluated the effect of addition of GnRH-A to the hCG therapy on plasma levels of T and 17 alpha-hydroxyprogesterone (17 OHP). All patients were treated with 1000 U of hCG in every 3rd day for 24 weeks. After 8 weeks of this regimen, GnRH-A, Buserelin (D-Ser-TBU-EA-LHRH), 200 micrograms per day sc, was added and given for 8 weeks. After cessation of analogue administration patients were followed for 8 further weeks. The levels of the two steroids did not differ markedly in the pre- and post-GnRH-A period. GnRH-A given for two months did not lower T or 17 OHP levels as in eugonadal men after similar treatment. The median T concentrations during GnRH-A tended to be increased, with plasma values higher (P less than 0.025) than the peak values observed during hCG alone. Since administration of Buserelin did not inhibit hCG-sustained steroid levels in these HH patients, it is conceivable that GnRH-A may have lacked a direct inhibitory gonadal effect in such experimental conditions.

17-alpha-Hydroxyprogesterone↗
PubMed1986

Enhancing detection of gonococcus in ejaculates of adult males using sperm dilution.

Specific cultures were used to detect growth of Neisseria Gonorrhoeae (NG) in 90 ejaculates of partners of childless marriages. Although no gonococcal growth was observed in undiluted semen, 9 out of 68 subjects with silent infection presented growth of NG in seminal plasma after dilution 1:2 with saline. It is concluded that semen dilution increases the chances of detection of NG in semen samples of asymptomatic gonococci carriers.

Adult↗
PubMed1986

[A case of spontaneous hematoma of the rectus abdominis muscle].

The authors describe a recently observed case of spontaneous hematoma of the abdominal rectus muscle. They go on from there to a thorough examination of this rare condition in the light of the latest contributions on the subject in the literature. After describing the anatomo-pathological, aetiopathogenetic and clinical aspects of the condition, the authors deal at some length with the diagnostic possibilities afforded by ultrasound in particular and with the indications for conservative therapeutic treatment, surgery being resorted to only in complicated cases or in cases where diagnostic doubts persist.

Abdominal Muscles↗
PubMed1983

Severe deficiency of natural killer activity in the peripheral blood of patients with hairy cell leukemia.

Natural killer (NK) activity against K-562 tumor cells was evaluated in peripheral blood leukocytes (PBL) obtained from untreated patients affected by hairy cell leukemia (HCL). NK activity present in PBL from 10 HCL patients was at least six-fold lower (p less than 0.01) than that present in PBL from 15 healthy donors. Decreased NK activity in HCL PBL was not due to dilution of the NK effector cells by the neoplastic cells; in fact, NK activity of PBL from 4 HCL patients with less than 5% circulating neoplastic cells was still five-fold lower (p less than 0.01) than that present in normal PBL. Partial characterization of the NK defect in HCL patients indicated that: (A) defective cytotoxicity was not dependent on the duration of the assay; (B) HCL PBL added to normal PBL during the assay did not exert suppressor activity; (C) the NK activity of HCL PBL could be potentiated in vitro by interferon; and (D) low levels of NK activity were associated with reduced numbers of circulating monocytes (p less than 0.01) and of large granular lymphocytes (LGL) (p less than 0.01). In conclusion, our results indicate that the low levels of NK activity present in the peripheral blood of HCL patients may be related to reduced numbers of circulating effector cells.

Adult↗