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G Cecchetto

Publications and source records attributed to G Cecchetto.

At least 37 records · Page 2Linked to original sources
PubMed1999

Testicular cystic dysplasia: evaluation of 3 new cases treated without surgery.

PURPOSE: We describe 3 cases of testicular cystic dysplasia that were diagnosed only by sonography to avoid an invasive approach. MATERIALS AND METHODS: Three patients 5, 8 and 12 years old, respectively, had increased testicular volume and/or intermittent pain. Sonographic examination of the testis by high frequency (7.5 mHz.) probes showed the typical onset of testicular cystic dysplasia, characterized by several small focal or diffuse intraparenchymal cystic formations. RESULTS: Biopsy or orchiectomy was not considered. At 16, 18 and 24 months of followup, respectively, testicular pain was absent in our 3 cases and sonographic findings were unchanged. CONCLUSIONS: Clinical and sonographic followup is considered sufficient to evaluate possible changes in the clinical course of this pathological condition which, although benign, still remains to be defined.

Child↗
PubMed1999

The hxB gene, necessary for the post-translational activation of purine hydroxylases in Aspergillus nidulans, is independently controlled by the purine utilization and the nicotinate utilization transcriptional activating systems.

Molybdenum-containing enzymes of the hydroxylase class (such as xanthine dehydrogenase, aldehyde oxidase and nicotinate dehydrogenase) require a terminal sulphur atom attached to the molybdenum to hydroxylate their specific substrates. The transulphurylation reaction is carried out in Drosophila melanogaster by the product of the ma-I gene. In Aspergillus nidulans, the activity of the isofunctional and homologous HxB protein is needed in at least two different metabolic contexts, when the organism grows on purines and when it grows on nicotinate as nitrogen sources. We show here that the expression of the hxB gene is not constitutive. It is induced independently and additively by the inducers of the purine and of the nicotinate utilization pathways. Each of these induction pathways is affected independently by mutations in their cognate genes, uric acid induction by mutations in the UaY protein and nicotinate and 6-nicotinate induction by those in the hxnR/aplA complex. It is, in both metabolic contexts, exquisitely sensitive to nitrogen metabolite repression and highly dependent on the AreA GATA factor.

Aspergillus nidulans↗
PubMed1998

Inflammatory pseudotumors of the lung in children: conservative or aggressive approach?

BACKGROUND: Inflammatory pseudotumors (inflammatory myofibroblastic tumors) of the lung are myofibroblastic lesions of controversial nosology. The concept that these are benign lesions has been recently questioned given their capacity for local invasion and recurrence. PROCEDURE AND RESULTS: We observed five children with inflammatory pseudotumors of the lung in whom the tumor was resected using the most limited excision possible. Unusually, in all five cases the tumor was localized in the right upper lobe: Three were parenchymal, and the others involved the bronchus. The three parenchymal masses underwent wedge resection, whereas the two bronchial lesions required ex-cision followed by a bronchoplasty and an up-per lobectomy, respectively. In all, the pathology showed a complete resection, and the patients had uneventful recoveries. Follow-ups, including CT and bronchoscopies, ranged from 4 to 8 years (mean of 6.4 years) with no signs of recurrence. CONCLUSIONS: Our limited experience supports the idea that excisional surgery is the treatment of choice for inflammatory pseudotumors of the lung. Such excisions, both diagnostic and curative, carry minimal risks and avoid unnecessary mutilation. Closely monitored follow-up is mandatory, as the natural history of this lesion is not yet well understood.

Adolescent↗
PubMed1998

Renal angiomyolipoma in children: diagnositc difficulty in 3 patients.

PURPOSE: Because angiomyolipoma is less common in children than in adults, its diagnosis can be difficult. We present 3 cases of pediatric angiomyolipoma in which diagnostic problems resulted due to the presenting characteristics. MATERIALS AND METHODS: We report on 3 children with unilateral renal angiomyolipoma. Computerized tomography (CT) and ultrasonography revealed 3 large renal masses, 20, 7 and 8 cm. in diameter, respectively. A correct diagnosis was not made preoperatively in any case by CT, ultrasound or fine needle biopsy. Wilms tumor was suspected in the first patient who received preoperative chemotherapy. Imaging was inconclusive in the other 2 cases. RESULTS: All patients underwent surgical exploration and subsequent nephrectomy due to the large size of the tumor. At followup 33, 23 and 13 months postoperatively all children were well without signs of recurrence. CONCLUSIONS: It has been reported that the demonstration of fat on renal ultrasound and CT can diagnose angiomyolipoma in 95% of the cases. Most radiologists rely solely on CT demonstration of lipid density in the renal mass to diagnose angiomyolipoma but the identification at imaging of lipid tissue may be difficult in small tumors. In our cases the fat content of the tumors was less than 10% despite the large size. This low fat content results in misdiagnosis, since fatty tissue is also present in other renal tumors, such as lipoma, liposarcoma, teratoma and Wilms tumors. We recommend conservative surgery when tumor size permits in pediatric patients with angiomyolipoma to avoid chemotherapy.

Adolescent↗
PubMed1997

Hypertensive cardiomegaly caused by an aldosterone-secreting adenoma in a newborn.

A case of primary hyperaldosteronism and cardiomegaly due to a unilateral adrenal adenoma in a newborn is presented. Some peculiarities, most likely in relation to the onset of the disease during fetal life were evident: plasma cortisol was slightly increased before surgery, plasma renin activity was elevated 9 months after surgery and mineralcorticoid receptors remained suppressed 4 months after surgery. Unilateral adrenalectomy reversed both hypertension and cardiomegaly. We speculate that cardiomegaly was related to both hyperaldosteronism and hypertension and that individual factors are involved in the pathogenesis of cardiomegaly in hyperaldosteronism.

Adenoma↗
PubMed1996

Nodular regenerative hyperplasia of the liver: description of two cases.

Nodular regenerative hyperplasia (NRH) of the liver is a condition of unknown origin, rarely occurring in children, usually accidentally discovered, described in association with a variety of clinical conditions and drugs. Confusion with other types of hepatic masses may pose a problem and for this reason NRH is considered a "tumor-like lesion." Histologically it consists of single or multiple regenerative foci. Hepatic failure and rupture of the liver have been rarely described as complications in adults, and not in children, and malignant transformation has not been demonstrated. Neither surgical removal nor other treatment is needed. These features are described as they were found in two patients we encountered.

Biopsy↗
PubMed1996

Resection of primary tumor at diagnosis in stage IV-S neuroblastoma: does it affect the clinical course?

PURPOSE: To determine whether resection of primary tumor has a favorable influence on outcome of infants (age 0 to 11 months) with stage IV-S neuroblastoma. PATIENTS AND METHODS: Between March 1976 and December 1993, 97 infants with previously untreated neuroblastoma diagnosed in 21 Italian institutions were classified as having stage IV-S disease. Seventy percent were younger than 4 months. Adrenal was the primary tumor site in 64 of 85 patients with a recognizable primary tumor. Liver was the organ most often infiltrated by the tumor (82 patients), followed by bone marrow and skin. RESULTS: The overall survival (OS) rate at 5 years in 80% and event-free survival (EFS) rate 68%. In 24 infants, the effect of resection of primary tumor could not be evaluated because of rapidly fatal disease progression (n = 8), absence of a primary tumor (n = 12), or partial resection (n = 4). Of 73 assessable patients, 26 underwent primary tumor resection at diagnosis: one died of surgical complications, one relapsed locally and died, and two others relapsed (one of these two locally) and survived, for a 5-year OS rate of 92% and EFS rate of 84%. Of the remaining 47 patients who did not undergo primary tumor resection at diagnosis 11 suffered unfavorable events, of whom five died, for an OS rate of 89% and EFS rate of 75% (no significant difference from previous group). Disease recurred at the primary tumor site in only one five who died, and in only one of six survivors of progression or relapse; in these patients, the primary tumor, located in the mediastinum, was successfully resected. CONCLUSION: Infants who underwent resection of the primary tumor at diagnosis had no better outcome than those in whom the decision was made not to operate.

Adrenal Gland Neoplasms↗
PubMed1995

Genetic and molecular characterization of a gene encoding a wide specificity purine permease of Aspergillus nidulans reveals a novel family of transporters conserved in prokaryotes and eukaryotes.

In Aspergillus nidulans, loss-of-function mutations in the uapA and azgA genes, encoding the major uric acid-xanthine and hypoxanthine-adenine-guanine permeases, respectively, result in impaired utilization of these purines as sole nitrogen sources. The residual growth of the mutant strains is due to the activity of a broad specificity purine permease. We have identified uapC, the gene coding for this third permease through the isolation of both gain-of-function and loss-of-function mutations. Uptake studies with wild-type and mutant strains confirmed the genetic analysis and showed that the UapC protein contributes 30% and 8-10% to uric acid and hypoxanthine transport rates, respectively. The uapC gene was cloned, its expression studied, its sequence and transcript map established, and the sequence of its putative product analyzed. uapC message accumulation is: (i) weakly induced by 2-thiouric acid; (ii) repressed by ammonium; (iii) dependent on functional uaY and areA regulatory gene products (mediating uric acid induction and nitrogen metabolite repression, respectively); (iv) increased by uapC gain-of-function mutations which specifically, but partially, suppress a leucine to valine mutation in the zinc finger of the protein coded by the areA gene. The putative uapC gene product is a highly hydrophobic protein of 580 amino acids (M(r) = 61,251) including 12-14 putative transmembrane segments. The UapC protein is highly similar (58% identity) to the UapA permease and significantly similar (23-34% identity) to a number of bacterial transporters. Comparisons of the sequences and hydropathy profiles of members of this novel family of transporters yield insights into their structure, functionally important residues, and possible evolutionary relationships.

Amino Acid Sequence↗
PubMed1995

A simple exam to screen superficial masses: fine-needle aspiration cytology.

Fine-needle aspiration cytology (FNAC) is now considered a useful tool in the evaluation of adult patients with mass lesions. We reviewed the experience with FNAC in our Paediatric Surgical Department. One hundred and eleven FNACs were performed in children with a superficial mass and no definite diagnosis. All the exams were done by the same physician using a fine needle and no anesthesia. We routinely used May-Grüwald-Giemsa and Papanicolaou staining. Patients age ranged from 20 days to 17 years, with a mean age of 6.5 years. A clinically benign pathology was cytologically confirmed in 90 cases (81%). All children did well at follow-up. Malignancy was diagnosed in eight cases (7.2%) and in all was confirmed with a surgical biopsy. In nine children (8.1%) the specimen was considered insufficient for definite diagnosis. In four cases (3.6%) the pathologist diagnosed a possible malignancy that was excluded at surgical biopsy. The sensitivity was 100% and the specificity was 96%. Our experience confirms that FNAC is a fast, cheap, simple, and accurate diagnostic method and should be used for screening in all children with doubtful superficial masses.

Adolescent↗
PubMed1995

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↗
PubMed1994

Genetic and molecular characterisation of purine permease genes of Aspergillus nidulans reveals a novel family of transporters conserved in prokaryotes and eukaryotes.

The ascomycete fungus Aspergillus nidulans can utilize purines (adenine, guanine, hypoxanthine, xanthine, and uric acid) as sole nitrogen sources [1]. The expression of most structural genes involved in the pathway of purine uptake and catabolism is subject to uric acid induction, mediated by the product of the positive regulatory gene uaY, and to nitrogen metabolite repression, mediated by the product of the general, positive-acting, GATA-like transcription factor, encoded by the areA gene [1].

Aspergillus nidulans↗
PubMed1994

Paratesticular rhabdomyosarcoma (RMS) and paraaortic lymphadenectomy.

This study is based on the experience of the Italian Cooperative Studies "AIEOP-RMS 79 and RMS 88". Between October 1979 and December 1989 299 children under 15 years of age with a histologically proven rhabdomyosarcoma (RMS) were examined. We analyzed the problem of the paratesticular localization paying particular attention to the role of surgery in dealing with paraaortic nodes. In the first study (RMS 79) the surgical exploration of retroperitoneal nodes was required: this procedure performed in 11 out of 14 patients affected by paratesticular RMS confirmed the negative data observed with diagnostic investigations. In RMS 88 study the sampling of retroperitoneal nodes was not required in cases with negative radiological findings but suggested in those cases with uncertain signs; two out of 8 patients underwent a laparotomy. In these two cases the results were negative. These 22 children were treated with an adjuvant chemotherapy after surgery and at present they show no evidence of disease.

Adolescent↗
PubMed1993

Cytokeratins patterns in childhood primary liver tumors.

Expression of cytokeratins no. 7 and no. 19, typical of the mature biliary tract and of embryonic and fetal hepatocytes, has been evaluated in primary liver tumors from 12 children. Of 7 children with hepatoblastoma, 6 were strongly reactive for cytokeratin no. 19 and only 4 were weakly positive for cytokeratin no. 7. In contrast, the remaining tumors, including 2 hepatocarcinomas, 1 sarcoma, 1 hamartoma and 1 hemangioma were positive for cytokeratin no. 7, while cytokeratin 19 was present in 1 hepatocarcinoma and in the hamartoma. All these tumors, as well as 1 hepatoblastoma and the sarcoma, were also reactive for cytokeratin no. 8, typical of hepatic cells.

Adolescent↗
PubMed1992

Latent hepatitis B virus infection in childhood hepatocellular carcinoma. Analysis by polymerase chain reaction.

The presence of hepatitis B virus (HBV) has been evaluated in liver specimens from 11 children with primary liver tumors and negative results of serologic testing for HBV markers. HBV-DNA sequences were detected by the polymerase chain reaction procedure, using different sets of oligonucleotide primers from highly conserved regions of HBV genome. Two of three children with histologic diagnosis of hepatocellular carcinoma were positive for HBV-DNA in the liver, whereas the remaining children, including six patients with hepatoblastoma, one patient with hemangioma, and one patient with hamartoma, were negative. These findings support the hypothesis of a primary role of HBV in the development of hepatocellular carcinoma in children from nonendemic areas and without overt HBV infection.

Adolescent↗
PubMed1991

Does hepatitis B virus play a role in primary liver cancer in children of Western countries?

Hepatitis B virus (HBV) infection was evaluated in serum and liver specimens of eight Italian children with primary liver cancer. All children were negative for HBV markers in serum but four of them showed HBV-DNA sequences and/or HBs antigen expression in the liver. In one case, viral DNA was present in both neoplastic and non-neoplastic tissue, while in one case HBV-DNA was detectable only in nontumoral tissue and in one case only in the tumor area. In these cases, scattered HBsAg was expressed in the cytoplasm of cells in normal part of the liver and in another case neoplastic cells secreted HBsAg in culture. In two cases, the histologic diagnosis was HCC; one case had mixed HPB and one had macrotrabecular HPB. All children were more than 1 year of age. The remaining four children were histologically diagnosed as HPB and were less than 1 year of age. These findings suggest that HBV may be a cofactor for the development of liver cancer also in children of Western countries and that the risk of infection progressively increases with age.

Carcinoma, Hepatocellular↗
PubMed1990

Neonatal malignant solid tumors.

We reviewed the 8 malignant solid tumors in children less than 1 month of age observed at the Pediatric Surgical Department of Padua University from 1968 to 1985. These were 6 neuroblastomas, 1 Wilms' tumor and 1 angiosarcoma; 5/8 are alive without evidence of disease with a median follow-up of 8 years. The importance of combined therapeutic approach and conservative surgery are stressed. The sensitiveness of infants to both chemotherapy and radiotherapy are considered. Surgery remains the treatment of choice when a radical resection is possible.

Combined Modality Therapy↗